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[Effects and mechanism of interleukin-17-modified mouse bone marrow mesenchymal stem cells on rejection reaction of allogeneic skin transplantation in mice]. Ma T X,Xu Y W,Jiang D Y Zhonghua shao shang za zhi = Zhonghua shaoshang zazhi = Chinese journal of burns To explore the effects and mechanism of interleukin-17 (IL-17)-modified mouse bone marrow mesenchymal stem cells (BMSCs) on the allogeneic skin transplantation in mice. (1) The femur, tibia, and humerus were isolated from five BALB/c mice (all female, aged 4 to 8 weeks, the same gender and age below) after sacrifice. BMSCs were isolated, purified, and cultured by whole bone marrow density gradient centrifugation combined with adherent separation method. The third passage of cells was used for morphological observation and identification of adipogenic and osteogenic differentiation. The fourth passage of cells was used for identification of the expression of stem cell surface markers. The third to sixth passages of BMSCs were pretreated with mouse recombinant IL-17 at a final mass concentration of 50 ng/mL for 5 days, and then were harvested for morphological observation. After being labeled with carbocyanine fluorescent dye (CM-Dil), IL-17-pretreated BMSCs and IL-17-unpretreated BMSCs were obtained for morphological observation and the labeling rates were calculated. (2) Forty-five C57BL/6J mice were divided into phosphate buffer solution (PBS) control group (=13), BMSCs alone group (=16), and BMSCs+ IL-17 group (=16) according to the random number table. One day before the skin transplantation of mice, 0.1 mL BMSCs (5×10(6) cells/mL) without CM-Dil labeling were injected to the 13 mice in BMSCs alone group through the tail vein, and 0.1 mL BMSCs (5×10(6) cells/mL) labeled with CM-Dil were injected to the other 3 mice in BMSCs alone group through the tail vein. IL-17-pretreated BMSCs (5×10(6) cells/mL) without CM-Dil labeling in the volume of 0.1 mL were injected to the 13 mice in BMSCs+ IL-17 group through the tail vein, and 0.1 mL IL-17-pretreated BMSCs (5×10(6) cells/mL) labeled with CM-Dil were injected to the other 3 mice in BMSCs+ IL-17 group through the tail vein. PBS in the volume of 0.1 mL was injected to the 13 mice in PBS control group through the tail vein. Forty-five BALB/c mice were used as donors, and forty-five treated C57BL/6J mice in the 3 groups were used as recipients to establish a back-to-back full-thickness skin transplantation model. On the 2nd day after transplantation, the same number of corresponding cells and the equal amount of PBS were injected to the recipient mice of each group again. On the 7th day after transplantation, three mice injected with CM-Dil-labeled BMSCs in BMSCs alone group and three mice injected with CM-Dil-labeled IL-17-pretreated BMSCs in BMSCs+ IL-17 group were sacrificed by cervical dislocation to track the CM-Dil-labeled BMSCs by fluorescence microscope, which was counted. After the dressing removal on the 6th day post transplantation, 7 mice were selected respectively from 13 mice in BMSCs alone group injected with BMSCs without CM-Dil-labeling, 13 mice in BMSCs+ IL-17 group injected with IL-17-pretreated BMSCs without CM-Dil-labeling, and 13 mice in PBS control group, respectively, to record the skin graft survival time. On the 8th day post transplantation, three of the remaining six mice in the three groups were taken for general observation of the grafted skin, serum levels of interferon-γ, IL-10, and transforming growth factor β (TGF-β) by enzyme-linked immunosorbent assay method, the percentage of CD4(+) CD25(+) forkhead/winged helix transcription factor p3 (Foxp3)(+) regulatory T cells (Tregs) in spleen by flow cytometer, and the histopathological observation of the grafted skin by hematoxylin eosin staining. The rest three mice in each group were also taken for histopathological observation as above on the 14th day post transplantation. Data were statistically analysed with independent sample test, one-way analysis of variance, and least significant difference test. (1) There were no significant differences in the morphology and size between IL-17-pretreated BMSCs and IL-17-unpretreated BMSCs on culture day 5. (2) After CM-Dil labeling, BMSCs and IL-17-pretreated BMSCs grew well, and the labeling rate was almost 100%. (3) On the 7th day post transplantation, there were 6.2±2.6 CM-Dil-labeled BMSCs per 100 fold visual field in the skin and adjacent subcutaneous tissue of mice in BMSCs alone group, which were significantly fewer than the 15.0±5.3 CM-Dil-labeled IL-17-pretreated BMSCs per 100 fold visual field in BMSCs+ IL-17 group (=-2.962, <0.05). (4) The skin graft survival time of mice in BMSCs alone group and BMSCs+ IL-17 group was (13.3±1.2) and (17.0±1.5) days respectively, significantly longer than (8.7±0.8) days in PBS control group (<0.01), and the skin graft survival time of mice in BMSCs+ IL-17 group was significantly longer than that in BMSCs alone group (<0.01). (5) On the 8th day post transplantation, most of the skin grafts of mice in PBS control group was black, scabby, and necrotic. Most of the skin grafts of mice in BMSCs alone group survived well, while all the skin grafts of mice in BMSCs+ IL-17 group survived well. (6) On the 8th day post transplantation, compared with those of PBS control group, the serum levels of IL-10 and TGF-β of mice in BMSCs alone group and BMSCs+ IL-17 group were significantly higher (<0.01), and the serum level of interferon-γ was significantly lower (<0.01). Compared with those of BMSCs alone group, the serum levels of IL-10 and TGF-β of mice in BMSCs+ IL-17 group were significantly higher (<0.01), and the serum level of interferon-γ was significantly lower (<0.01). (7) On the 8th day post transplantation, the percentages of CD4(+) CD25(+) Foxp3(+) Treg in spleen of mice in BMSCs alone group and BMSCs+ IL-17 group were significantly higher than the percentage of PBS control group (<0.01), and the percentage of CD4(+) CD25(+) Foxp3(+) Treg in spleen of mice in BMSCs+ IL-17 group was significantly higher than that of BMSCs alone group (<0.01). (8) On the 8th day post transplantation, infiltration of a large number of inflammatory cells and necrosis of epidermis and dermis were found in the skin grafts of mice in PBS control group; focal infiltration of inflammatory cells and slight epidermal degeneration were found in the skin grafts of mice in BMSCs alone group; the skin appendages of the skin grafts of mice in BMSCs+ IL-17 group survived well with angiogenesis. On the 14th day post transplantation, the skin grafts of mice in BMSCs alone group showed extensive infiltration of inflammatory cells, severe epidermal degeneration and focal necrosis; the skin grafts of mice in BMSCs+ IL-17 group showed focal infiltration of inflammatory cells and slight epidermal degeneration; the skin grafts of mice in PBS control group were completely necrotic. IL-17 can reduce the immune rejection in allogeneic skin grafting and prolong the survival time of mouse skin grafts by improving mice BMSCs' capabilities to induce immune tolerance and enhancing the homing ability of BMSCs. 10.3760/cma.j.cn501120-20190510-00232
Molecular mechanisms of vitamin D action. Haussler Mark R,Whitfield G Kerr,Kaneko Ichiro,Haussler Carol A,Hsieh David,Hsieh Jui-Cheng,Jurutka Peter W Calcified tissue international The hormonal metabolite of vitamin D, 1α,25-dihydroxyvitamin D(3) (1,25D), initiates biological responses via binding to the vitamin D receptor (VDR). When occupied by 1,25D, VDR interacts with the retinoid X receptor (RXR) to form a heterodimer that binds to vitamin D responsive elements in the region of genes directly controlled by 1,25D. By recruiting complexes of either coactivators or corepressors, ligand-activated VDR-RXR modulates the transcription of genes encoding proteins that promulgate the traditional functions of vitamin D, including signaling intestinal calcium and phosphate absorption to effect skeletal and calcium homeostasis. Thus, vitamin D action in a particular cell depends upon the metabolic production or delivery of sufficient concentrations of the 1,25D ligand, expression of adequate VDR and RXR coreceptor proteins, and cell-specific programming of transcriptional responses to regulate select genes that encode proteins that function in mediating the effects of vitamin D. For example, 1,25D induces RANKL, SPP1 (osteopontin), and BGP (osteocalcin) to govern bone mineral remodeling; TRPV6, CaBP(9k), and claudin 2 to promote intestinal calcium absorption; and TRPV5, klotho, and Npt2c to regulate renal calcium and phosphate reabsorption. VDR appears to function unliganded by 1,25D in keratinocytes to drive mammalian hair cycling via regulation of genes such as CASP14, S100A8, SOSTDC1, and others affecting Wnt signaling. Finally, alternative, low-affinity, non-vitamin D VDR ligands, e.g., lithocholic acid, docosahexaenoic acid, and curcumin, have been reported. Combined alternative VDR ligand(s) and 1,25D/VDR control of gene expression may delay chronic disorders of aging such as osteoporosis, type 2 diabetes, cardiovascular disease, and cancer. 10.1007/s00223-012-9619-0
UVB therapy increases 25(OH) vitamin D syntheses in postmenopausal women with psoriasis. Osmancevic Amra,Landin-Wilhelmsen Kerstin,Larkö Olle,Mellström Dan,Wennberg Ann-Marie,Hulthén Lena,Krogstad Anne-Lene Photodermatology, photoimmunology & photomedicine BACKGROUND:Vitamin D3 is produced in the epidermis by ultraviolet (UV) radiation (290-315 nm) of 7-dehydrocholesterol. A similar range of 290-320 nm (broadband UVB) has been successfully used for years to treat psoriasis. The aim of this study was to investigate whether UVB therapy was able to influence vitamin D synthesis in psoriasis patients. METHODS:Twenty-four postmenopausal, white Caucasian women, aged 69 +/- 5.9 (mean +/- SD), with active plaque psoriasis, were treated with broadband UVB two to three times per week for 8-12 weeks. The serum concentrations of calcidiol (25(OH)D3), calcitriol (1,25(OH)2D3), intact parathyroid hormone (PTH), thyroid hormones, osteocalcin, calcium and creatinine were measured before the first and after the last dose of radiation. Bone density was measured using Dual-Energy X-ray Absorptiometry (Hologic Delphi A) at the hip and lumbar spine. RESULTS:Serum levels of 25(OH)D3 increased from 36.8 +/- 17 ng/ml (mean +/- SD) to 59.6 +/- 18.7 ng/ml (P<0.001) after the UVB treatment period. Serum PTH decreased from 62.8 +/- 25.7 ng/l to 48.2 +/- 17.4 ng/l (P<0.001). Secondary hyperparathyroidism (PTH>65 ng/l) was revealed in seven patients (29%) in whom PTH values were suppressed by the UVB therapy. The serum levels of calcitriol, calcium, osteocalcin, thyroid hormones and creatinine were unaltered. CONCLUSION:UVB therapy in elderly psoriatic women improved psoriasis, increased serum 25(OH)D3 synthesis and reduced serum PTH concentrations. 10.1111/j.1600-0781.2007.00301.x
[A quantitative study of the presence of interleukin-1 and interleukin-6 in cholesteatoma of the middle ear]. Aumente P O,Bujía J,Kim C,Jiménez Giménez J,López Villarejo P Acta otorrinolaringologica espanola Cholesteatoma of the middle ear is an inflammatory disease characterized by the presence of a keratinized squamous layer that leads to bone destruction. The process may be mediated by various factors (interleukins) produced by an activated macrophages and keratinocytes. Interleukin-1 (IL-1) and interleukin-6 (IL-6) concentrations were measured in extracts of cholesteatoma and normal tissue using the enzyme immunoassay technique (ELISA) after protein concentrations were determined. IL-1 alpha and IL-6 had higher concentrations in cholesteatoma than in normal skin and played a prominent role in bone resorption.
Can keratinocytes cause failure of osseointegration? Khwaja S,Curry A,Chaudhry I H,Green K M J The Journal of laryngology and otology AIM:Bone-anchored hearing aids are well established, implanted devices. We present two patients who suffered mixed hearing loss and who underwent titanium implant placement in the temporal bone to enable attachment of bone-anchored hearing aids. Osseointegration is necessary for such implants to function. We report these two cases to highlight how such osseointegration may be disrupted. METHOD:Attached tissue from the explanted or removed titanium implants was examined by transmission electron microscopy and histopathological analysis. RESULTS:Attached tissue from both implants showed the presence of keratinocytes at the titanium implant and living bone interface. This was confirmed by histopathological analysis. In one case, there was frank keratinocyte proliferation, which had led to osseointegration failure; in the other case, such proliferation was present but not so advanced. CONCLUSION:These findings suggest that, in the cases reported, keratinocytes implanted between the titanium and the living bone, leading to disruption of osseointegration. 10.1017/S002221510800409X
Role of interleukin 6 in epithelial hyperproliferation and bone resorption in middle ear cholesteatomas. Bujía J,Kim C,Ostos P,Kastenbauer E,Hültner L European archives of oto-rhino-laryngology : official journal of the European Federation of Oto-Rhino-Laryngological Societies (EUFOS) : affiliated with the German Society for Oto-Rhino-Laryngology - Head and Neck Surgery Locally produced pro-inflammatory cytokines are considered to play an important role in the initiation and/or maintenance of inflammatory diseases. In cholesteatomatous lesions there are increased levels of some cytokines and inflammatory mediators like interleukin 1, tumor necrosis factor and colony-stimulating factor, etc. Interleukin 6 (IL-6) can be produced by different cells present in cholesteatoma (e.g. keratinocytes, lymphocytes, fibroblasts and macrophages). Until now, no data have been available on the role of IL-6 in cholesteatoma. In this study we used immunohistochemistry to investigate the presence and distribution of IL-6 in tissue samples from cholesteatoma patients. Levels of the cytokine were quantified in tissue extracts using an enzyme-linked immunosorbent assay. Finally, the presence of biologically active IL-6 was analyzed in the murine cell line 7TD1. Human skin samples obtained from the external ear canal were used as controls. Using the anti-IL-6 antibody in an alkaline phosphatase anti alkaline phosphatase technique, a moderate diffuse staining of the whole epidermis was observed in sections of normal skin. In cryostat sections of cholesteatoma samples, a stronger staining of the whole epithelium was observed. Many of the cells infiltrating the cholesteatoma stroma also showed positive immunostainings. The concentration of IL-6 in relation to the total protein concentration in cholesteatoma (119.33 +/- 30) were higher than in human skin (9.16 +/- 13). While IL-6 activity was not detected in skin samples, two of the ten cholesteatoma samples studied showed a stimulatory effect when incubated with the cell line 7TD1. The overexpression of IL-6 in middle ear cholesteatoma suggests a participation of this cytokine in some of the clinical features seen: epithelial hyperproliferation and bone resorption. The absence of biological activity in the majority of the cholesteatoma samples points to the presence of natural inhibitors for IL-6.
Opening of chloride channels by 1α,25-dihydroxyvitamin D3 contributes to photoprotection against UVR-induced thymine dimers in keratinocytes. Sequeira Vanessa B,Rybchyn Mark S,Gordon-Thomson Clare,Tongkao-On Wannit,Mizwicki Mathew T,Norman Anthony W,Reeve Vivienne E,Halliday Gary M,Mason Rebecca S The Journal of investigative dermatology UVR produces vitamin D in skin, which is hydroxylated locally to 1α,25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3)). 1,25(OH)(2)D(3) protects skin cells against UVR-induced DNA damage, including thymine dimers, but the mechanism is unknown. As DNA repair is inhibited by nitric oxide (NO) products but facilitated by p53, we examined whether 1,25(OH)(2)D(3) altered the expression of nitrotyrosine, a product of NO, or p53 after UVR in human keratinocytes. 1,25(OH)(2)D(3) and the nongenomic agonist 1α,25-dihydroxylumisterol(3) reduced nitrotyrosine 16 hours after UVR, detected by a sensitive whole-cell ELISA. p53 was enhanced after UVR, and this was further augmented in the presence of 1,25(OH)(2)D(3). DIDS (4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid), a chloride channel blocker previously shown to prevent 1,25(OH)(2)D(3)-induced chloride currents in osteoblasts, had no effect on thymine dimers on its own but prevented the 1,25(OH)(2)D(3)-induced protection against thymine dimers. Independent treatment with DIDS, at concentrations that had no effect on thymine dimers, blocked UVR-induced upregulation of p53. In contrast, reduction of nitrotyrosine remained in keratinocytes treated with 1,25(OH)(2)D(3) and DIDS at concentrations shown to block decreases in post-UVR thymine dimers. These results suggest that 1,25(OH)(2)D(3)-induced chloride currents help protect from UVR-induced thymine dimers, but further increases in p53 or reductions of nitrotyrosine by 1,25(OH)(2)D(3) are unlikely to contribute substantially to this protection. 10.1038/jid.2012.343
[New immunobiologic trends concerning etiopathogenicity of cholesteatoma]. Bujía J Anales otorrinolaringologicos ibero-americanos After an epoch in which was pretended to explain the etiopathogenetic phenomena observed in Cholesteatoma through enzymatic studies, nowadays other investigations focus the topic in the possible presence of immunobiologic alterations at cellular level, so the research work is directed to the occurrence, distribution and activity of several growth factors and leukins. In this paper the AA. made a perusal of the new acquisitions and devote themselves to two important aspects of the cholesteatoma: the biologic behaviour of the squamous cell epithelia with an uncontrolled growth and to the immunobiologic mechanisms responsible for the bone resorption.
Production of parathyroid-hormone-related protein by cholesteatoma cells in culture. Cheshire I M,Blight A,Ratcliffe W A,Proops D W,Heath D A Lancet (London, England) Specimens of cholesteatoma were removed at surgery from five patients who had evidence of bone resorption. Parathyroid-hormone-related protein (PTHrP) was detected, by radioimmunoassay, in conditioned media from keratinocyte cultures derived from all five samples. Concentrations of PTHrP in conditioned media from secondary cultures were higher for the cholesteatoma cells than for normal keratinocytes from controls matched for age and sex. Thus, production of PTHrP by cholesteatoma may be a contributory factor in the bone destruction commonly associated with this disorder. 10.1016/0140-6736(91)91902-7
The effect of conditioned medium from connective tissue fibroblasts and epithelium on calcium release from mouse calvarial organ culture. Cochran D L,Rouse C A Archives of oral biology Fibroblasts from periodontal ligament and gingival explants were cultured in vitro. The conditioned media from four different periodontal ligament and four gingival explant cultures were examined to determine their effect on calcium release in mouse calvarial organ culture. All the cultures stimulated calcium release, with a range of 20.6-43% over control. Conditioned media from two periodontal ligament cultures and a gingival culture significantly stimulated calcium release from the bone organ culture. The stimulatory activity in the oral fibroblasts cell cultures was compared to that in conditioned medium from two non-oral, established, fibroblasts cell lines and an epidermal keratinocyte cell line. Similar to the oral fibroblast cultures, conditioned medium from all three cell lines resulted in stimulation of calcium release in the bone culture assay. In order to characterize the bone-stimulating activity, a 0.4 micron membrane was used to separate the cell cultures from the bone organ culture. Both gingival and periodontal ligament fibroblast cultures gave values for calcium release significantly less than control when the separating membrane was used. Both non-oral cell lines and the epidermal keratinocyte cell line gave values for calcium release similar to those when no membrane was used. These results suggest that oral fibroblasts, but not non-oral fibroblasts and epidermal keratinocytes, release a unique bone-resorption stimulating activity. 10.1016/0003-9969(93)90156-g
Squamous cell carcinomas often produce more than a single bone resorption-stimulating factor: role of interleukin-1 alpha*. Nowak R A,Morrison N E,Goad D L,Gaffney E V,Tashjian A H Endocrinology Several cultured human squamous cell carcinoma cell lines (SCC-4, SCC-12B2, SCC-12F2, EC-GI-10, and BEN) and one normal keratinocyte line (Epy-1) were investigated for the production of bone resorption-stimulating activity (BRSA). Conditioned medium (CM) from each of the six cell lines stimulated bone resorption in neonatal mouse calvariae in culture. The BRSA of SCC-12F2 and EC-GI-10 was inhibited completely by antibody to interleukin-1 alpha (IL-1 alpha), whereas the BRSA in CM from the BEN, SCC-4, SCC-12B2, and Epy-1 cell lines was only partially inhibited by anti-IL-1 alpha. Addition of indomethacin to the calvarial cultures also partially inhibited the BRSA from EC-GI-10, SCC-4, SCC-12B2, and Epy-1 cells; the BRSA from BEN and SCC-12F2 cells was inhibited completely by indomethacin. cAMP production by calvariae was determined after a 60-min incubation with CM. CM from EC-GI-10, BEN, SCC-4, and Epy-1 stimulated cAMP production by bone. Preincubation of CM from BEN, EC-GI-10, SCC-4, and Epy-1 cells with two antisera against PTH-related protein [PTHrP; one specific for two PTHrP-(1-141), the other recognizing both PTHrP-(1-40) and PTHrP-(1-141)] completely inhibited the cAMP-stimulating activity. Using specific enzyme-linked immunosorbent assays for IL-1 alpha and IL-1 beta, IL-1 alpha was measured in CM of the SCC-4, SCC-12B2, SCC-12F2, and Epy-1 cell lines. IL-1 beta was undetectable (less than 0.1 ng/ml) in CM from all cell lines. Our findings indicate that the BRSA secreted by SCC-12F2 cells can be accounted for largely or entirely by IL-1 alpha, while the activity produced by SCC-12B2 includes IL-1 alpha and another unknown factor(s). The BRSA produced by EC-GI-10, BEN, SCC-4, and Epy-1 cells includes both IL-1 alpha and PTHrP. We conclude that IL-1 alpha may be a more prevalent and biologically significant component of the BRSA produced by SCCs than previously recognized. 10.1210/endo-127-6-3061
Murine matrix metalloproteinase 9 gene. 5'-upstream region contains cis-acting elements for expression in osteoclasts and migrating keratinocytes in transgenic mice. Munaut C,Salonurmi T,Kontusaari S,Reponen P,Morita T,Foidart J M,Tryggvason K The Journal of biological chemistry Knowledge about the regulation of cell lineage-specific expression of extracellular matrix metalloproteinases is limited. In the present work, the murine matrix metalloproteinase 9 (MMP-9) gene was shown to contain 13 exons, and the 2.8-kilobase pair upstream region was found to contain several common promoter elements including a TATA box-like motif, three GC boxes, four AP-1-like binding sites, an AP-2 site, and three PEA3 consensus sequences that may be important for basic activity of the gene. In order to identify cell-specific regulatory elements, constructs containing varying lengths of the upstream region in front of a LacZ reporter gene were made and studied for expression in transgenic mice generated by microinjection into fertilized oocytes. Analyses of the mice revealed that the presence of sequences between -2722 and -7745 allowed for expression in osteoclasts and migrating keratinocytes, i. e. cells that have been shown to normally express the enzyme in vivo. The results represent the first in vivo demonstration of the location of cell-specific control elements in a matrix metalloproteinase gene and show that element(s) regulating most cell-specific activities of 92-kDa type collagenase are located in the -2722 to -7745 base pair region. 10.1074/jbc.274.9.5588
BM-40 (osteonectin, SPARC) is expressed both in the epidermal and in the dermal compartment of adult human skin. Hunzelmann N,Hafner M,Anders S,Krieg T,Nischt R The Journal of investigative dermatology BM-40 (Osteonectin, SPARC) is the most abundant glycoprotein secreted by human osteoblasts. In situ hybridization studies on the expression of BM-40 mRNA in murine tissues have demonstrated the highest levels of transcripts in bone, but expression was also observed in several other mesenchymal tissues. In contrast, little is known about the expression of BM-40 in human tissues, especially in skin. Total RNA obtained from normal human skin was analyzed by northern blotting and revealed a marked expression of BM-40. To analyze its expression in vivo, in situ hybridization was performed, demonstrating that BM-40 is expressed in fibroblasts, smooth muscle, and endothelial cells in the dermis. Interestingly, BM-40 mRNA was also detected throughout the basal, spinous, and granular layers in the epidermis of adult human skin. Further analysis by immunohistochemistry revealed a marked deposition in the dermis that was most intense directly below the basement membrane in the papillary dermis and around vascular as well as glandular structures. In the epidermis, BM-40 protein could be detected intercellularly in suprabasal layers. This finding is further supported by the intercellular deposition of BM40 detected by immunofluorescence in cultured keratinocytes. This study demonstrates that BM-40 that has previously been thought to be exclusively expressed in extracellular matrix producing cells may in fact play a role in differentiation and maintenance of the epidermis. 10.1046/j.1523-1747.1998.00094.x
Bisphosphonate inhibits the expression of cyclin A2 at the transcriptional level in normal human oral keratinocytes. Lee Rachel S,Sohn Suhjin,Shin Ki-Hyuk,Kang Mo K,Park No-Hee,Kim Reuben H International journal of molecular medicine Nitrogen-containing bisphosphonates (N-BPs) are the most widely used anti-resorptive agents in the treatment of bone-related diseases. N-BPs inhibit bone resorption by specifically targeting osteoclasts, bone-resorbing cells. However, soft tissue toxicity, such as oral or gastrointestinal (GI) ulcerations has frequently been reported in N-BP users, suggesting that N-BPs may also directly target cells other than osteoclasts. Previously, we reported that BPs inhibit proliferation without inducing the apoptosis of normal human oral keratinocytes (NHOKs). However, the molecular mechanisms through which N-BPs inhibit the proliferation of NHOKs are not yet fully understood. In this study, we performed gene expression profiling in N-BP-treated NHOKs and identified cyclin A2 as one of the most commonly downregulated genes. When the NHOKs were treated with N-BPs, we found that the level of cyclin A2 was suppressed in a dose- and time-dependent manner. In addition, the protein level of cyclin A2 was also significantly lower in oral epithelial cells in N-BP-treated oral mucosal tissue constructs. Cyclin A2 promoter reporter assay revealed that N-BPs inhibited the luciferase activity, indicating that the inhibition of cyclin A2 expression occurs at the transcriptional level. Furthermore, N-BPs did not alter the expression of cyclin A2 in normal human oral fibroblasts (NHOFs), suggesting that the effect of N-BPs on cyclin A2 expression may be cell-type specific. Thus, the findings of our study demonstrate that the inhibition of NHOK proliferation by N-BPs is mediated, at least in part, by the suppression of cyclin A2 expression at the transcriptional level, which may explain the underlying mechanisms of soft tissue toxicity by N-BPs. 10.3892/ijmm.2017.3066
Evidence for multiple bone resorption-stimulating factors produced by normal human keratinocytes in culture. Fried R M,Voelkel E F,Rice R H,Levine L,Tashjian A H Endocrinology Conditioned medium from cultured normal human foreskin keratinocytes enhanced the release of calcium from neonatal mouse calvaria in organ culture. Unfractionated keratinocyte-conditioned medium (KCM) stimulated bone resorption in a dose-dependent manner, but it did not increase the concentration of prostaglandin E2 (PGE2) in the bone culture medium until a maximal dose of KCM for resorption was used. Furthermore, inhibitors of PGE2 synthesis, indomethacin, ibuprofen, and piroxicam, did not inhibit KCM-induced calcium release. High concentrations of KCM increased cAMP production by calvaria in the presence of isobutylmethylxanthine, but the increase was small compared with that produced by a dose of bovine PTH that caused a similar level of bone resorption. The bone resorption-stimulating activity of KCM was not lost after incubation at 56 C for 60 min, but it was lost after heating at 100 C for 10 min. Fractionation of KCM by gel filtration chromatography revealed two distinct peaks of bone resorption-stimulating activity. One peak, KCMI, caused a significant increase in bone resorption at 2 micrograms protein/ml. KCMI did not increase medium PGE2, and inhibition of PGE2 synthesis in bone had no effect on KCMI-induced bone resorption. KCMI failed to increase cAMP production by human osteosarcoma SaOS-2 cells. Another peak, KCMII, caused a dose-dependent increase in bone resorption, and a significant increase in medium calcium was noted at a 20-fold lower concentration (0.1 microgram protein/ml) than with KCMI. In contrast to KCMI, the increase in bone resorption stimulated by KCMII was accompanied by a parallel increase in the production of PGE2, and inhibition of PGE2 synthesis completely inhibited the bone resorption-stimulating activity of KCMII. KCMII also caused an increase in cAMP production by SaOS-2 cells. We conclude that KCM contains at least two distinct bone resorption-stimulating factors, one of which acts via a PG-mediated mechanism and the other by a PG-independent pathway. 10.1210/endo-122-6-2467
Effects of isoflavones from red clover (Trifolium pratense) on skin changes induced by ovariectomy in rats. Circosta Clara,De Pasquale Rita,Palumbo Dora R,Samperi Stefania,Occhiuto Francesco Phytotherapy research : PTR Estrogens have a profound influence on skin. The relative hypoestrogenism that accompanies menopause exacerbates the deleterious effects of both intrinsic and environmental aging. Estrogens improve skin in many ways. Among these, they increase collagen content, skin thickness and improve skin moisture. There is evidence that diets with high levels of phytoestrogenic isoflavones are associated with a low incidence of menopausal symptoms and osteoporosis. Plant extracts such as red clover, which contain high levels of isoflavones, have been used to reduce menopausal symptoms and have been shown to reduce bone loss in healthy women. In this study to investigate the effects of red clover isoflavones on skin aging, the histology of the skin, skin thickness and the amount of total collagen determined by a colorimetric method, were studied in ovariectomized rats after treatment for 14 weeks with a red clover extract standardized to contain 11% isoflavones determined by HPLC. In ovariectomized rats the thickness and keratinization of the epidermis were reduced; glands were less in number and vascularity was poor; the distribution and morphology of the collagen bundles and elastic fibers were altered. Whereas the skin of the ovariectomized rats treated with red clover isoflavones (20 and 40 mg of total isoflavones daily for 14 weeks) appeared well organized with a normal epidermis with uniform thickness and regular keratinization; vascularity, collagen and elastic fibers were well developed. The amount of collagen significantly increased in the treated group in comparison with the control group. These findings suggest that red clover isoflavones are effective in reducing skin aging induced by estrogen deprivation. 10.1002/ptr.2017
Bone formation by BMP-7-transduced human gingival keratinocytes. Rutherford R B,Racenis P,Fatherazi S,Izutsu K Journal of dental research BMPs are a family of pleiotropic signaling molecules involved at various stages in the formation of bones and teeth. In addition, recombinant BMP can induce bone and dentin regeneration when applied directly to adult tissues. We have shown that fibroblasts transduced ex vivo by BMP cDNA delivered by recombinant adenoviruses induce bone formation and convert to osteoblasts upon implantation in vivo. To determine if this osteogenic capacity was limited to fibroblasts, we found that BMP-7-transduced human oral keratinocyte cells (HOKC) also formed ectopic bone. The ossicles formed by the BMP-7-transduced HOKC were smaller and more dense than those formed by BMP-7-transduced human gingival fibroblasts (HGF). Implanted HOKC were localized adjacent to the developing bone by immunocytochemical detection of keratin expression. However, no bone-like tissue formed when HOKC were implanted into diffusion chambers in vivo. We conclude that BMP-transduced HOKC secrete BMP and form bone in vivo but, unlike BMP-transduced HGF, do not transdifferentiate to osteoblasts. 10.1177/154405910308200410
Differentiation of epidermal Langerhans cells in macrophage colony-stimulating-factor-deficient mice homozygous for the osteopetrosis (op) mutation. Takahashi K,Naito M,Shultz L D The Journal of investigative dermatology The osteopetrosis (op) mutation is within the gene for macrophage colony-stimulating factor (M-CSF). Homozygotes (op/op) lack M-CSF activity and show abnormalities in the differentiation of osteoclasts and other cells within the macrophage lineage. The effect of the op mutation on the development of Langerhans cells (LC) was determined in order to assess differentiation of such cells in vivo in the absence of M-CSF. (C57BL/6J X C3HeB/FeJ)F2-op/op and +/? Littermate control mice were raised from +/? breeders obtained from the Jackson Laboratory. The mice were killed with ether anesthesia at 4 weeks after birth and skin specimens were excised and examined by immunohistochemistry using anti-mouse pan macrophage monoclonal antibodies (MoAb), F4/80 and BM8; anti-mouse LC MoAb, NLDC-145, M1-8, and MIDC8; and anti-mouse Ia MoAb, M5/114. In epidermal sheets, numbers of LC were counted. Histochemical staining of adenosine diphosphatase (ADPase) localization was also performed as a marker of LC. Epidermal LC from op/op mice showed reactivity with all these MoAb. Numbers of LC were slightly reduced, but the reduction was not significant statistically. The presence of Birbeck granules in LC of op/op mice was confirmed by electron microscopy but the cytoplasmic projection of LC was not prominent. From these results, it appears obvious that the development and differentiation of LC do not require M-CSF. 10.1111/1523-1747.ep12668982
Grey-lethal mutation induces severe malignant autosomal recessive osteopetrosis in mouse and human. Chalhoub Nader,Benachenhou Nadia,Rajapurohitam Venkatesh,Pata Monica,Ferron Mathieu,Frattini Annalisa,Villa Anna,Vacher Jean Nature medicine The spontaneous mouse grey-lethal (gl) mutation is responsible for a coat color defect and for the development of the most severe autosomal recessive form of osteopetrosis. Using a positional cloning approach, we have mapped and isolated the gl locus from a approximately 1.5 cM genetic interval. The gl locus was identified in a bacterial artificial chromosome (BAC) contig by functional genetic complementation in transgenic mice. Genomic sequence analysis revealed that the gl mutation is a deletion resulting in complete loss of function. The unique approximately 3 kb wild-type transcript is expressed primarily in osteoclasts and melanocytes as well as in brain, kidney, thymus and spleen. The gl gene is predicted to encode a 338-amino acid type I transmembrane protein that localizes to the intracellular compartment. Mutation in the human GL gene leads to severe recessive osteopetrosis. Our studies show that mouse Gl protein function is absolutely required for osteoclast and melanocyte maturation and function. 10.1038/nm842
Expression of bone morphogenetic protein-2 messenger ribonucleic acid in cholesteatoma fibroblasts. Schmidt Marianne,Schler Gabriele,Gruensfelder Petra,Hoppe Florian Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology HYPOTHESIS:The aim of the study was to evaluate the role of bone morphogenetic protein-2 (BMP-2) in the pathology of middle ear cholesteatoma. BACKGROUND:Middle ear cholesteatoma is a chronic inflammatory disease associated with destruction of the temporal bone and marked by increased expression levels of diverse cytokines. Bone remodeling associated with this disease is mainly caused by the action of osteoclasts. It has been shown that BMP-2 expression is inducible by interleukin 1 in synovial fibroblasts and that BMP-2 in combination with interleukin 1alpha is able to stimulate the formation of osteoclast-like multinucleated cells in co-cultures of osteoblast-like cells and hematopoietic cells. METHODS:By using Northern hybridizations, we examined the messenger ribonucleic acid expression of BMP-2 in keratinocytes and fibroblasts derived from normal external ear canal skin (EACS) and from cholesteatoma, respectively. RESULTS:We show that normal EACS fibroblasts do not express BMP-2, whereas keratinocytes of both EACS and cholesteatoma origin are positive for the BMP-2 transcript. In contrast to EACS fibroblasts, BMP-2 is clearly expressed in cholesteatoma perimatrix fibroblasts. Incubation of normal fibroblasts with cholesteatoma extracts caused the transcription of BMP-2. Interleukin 1alpha, bacterial endotoxin, or bovine keratin, however, were not able to initiate BMP-2 expression in normal fibroblasts. CONCLUSION:In view of the above data, it is tempting to speculate that BMP-2 expression might play a role in cholesteatoma pathology. 10.1097/00129492-200205000-00007
Bcl2 regulation by the melanocyte master regulator Mitf modulates lineage survival and melanoma cell viability. McGill Gaël G,Horstmann Martin,Widlund Hans R,Du Jinyan,Motyckova Gabriela,Nishimura Emi K,Lin Yi-Ling,Ramaswamy Sridhar,Avery William,Ding Han-Fei,Jordan Siobhán A,Jackson Ian J,Korsmeyer Stanley J,Golub Todd R,Fisher David E Cell Kit/SCF signaling and Mitf-dependent transcription are both essential for melanocyte development and pigmentation. To identify Mitf-dependent Kit transcriptional targets in primary melanocytes, microarray studies were undertaken. Among identified targets was BCL2, whose germline deletion produces melanocyte loss and which exhibited phenotypic synergy with Mitf in mice. BCL2's regulation by Mitf was verified in melanocytes and melanoma cells and by chromatin immunoprecipitation of the BCL2 promoter. Mitf also regulates BCL2 in osteoclasts, and both Mitf(mi/mi) and Bcl2(-/-) mice exhibit severe osteopetrosis. Disruption of Mitf in melanocytes or melanoma triggered profound apoptosis susceptible to rescue by BCL2 overexpression. Clinically, primary human melanoma expression microarrays revealed tight nearest neighbor linkage for MITF and BCL2. This linkage helps explain the vital roles of both Mitf and Bcl2 in the melanocyte lineage and the well-known treatment resistance of melanoma. 10.1016/s0092-8674(02)00762-6
New aspects of galectin functionality in nuclei of cultured bone marrow stromal and epidermal cells: biotinylated galectins as tool to detect specific binding sites. Purkrábková Tereza,Smetana Karel,Dvoránková Barbora,Holíková Zuzana,Böck Corina,Lensch Martin,André Sabine,Pytlík Robert,Liu Fu-Tong,Klíma Jirí,Smetana Karel,Motlík Jan,Gabius Hans-Joachim Biology of the cell Nuclear presence of galectins suggests a role of these endogenous lectins in the regulation of transcription, pre-mRNA splicing and transport processes. Therefore, detection and localization of nuclear binding sites for galectins by a new methodological step, has potential to further functional analysis. In the first step of our model study we monitored the nuclear expression of galectins-1 and -3 in cultured stromal cells of human bone marrow and human/porcine keratinocytes. To enable detection and localization of galectin-specific binding sites, we used purified galectins biotinylated without loss of activity as cytochemical tool. The degree of labeling of the probes was determined by adapting two-dimensional gel electrophoresis and calculating pI changes in response to stepwise chemical modification of basic and acidic side chains by the biotinylation reagents. Binding studies revealed positivity for galectin-1, whereas galectins-3, -5, and -7 were not reactive with nuclear sites under identical conditions in bone marrow stromal cells and keratinocytes prepared from hair follicle enriched for stem cells. Inhibition by lactose indicated an involvement of the carbohydrate recognition domain in nuclear binding of galectin-1. Colocalization of the galectin-1-dependent signal with the SC35 splicing factor and sensitivity toward RNase treatment argued in favor of galectin binding in nuclear speckles, albeit only for a small fraction of the cells. Epidermal cells positive for galectin-1-binding sites expressed DeltaNp63 known as a potential marker of stem cells. Based on cytokeratin expression cells with nuclear binding of labeled galectin-1 were basal and not suprabasal cells. Regarding proliferation, no relationship to the expression of a proliferation marker, Ki-67, was observed. The nucleolar signal colocalized with fibrillarin and nucleophosmin/B23 as representatives of nucleolar proteins in both types of studied cells. In conclusion, the application of labeled galectins to localize accessible binding sites adds a new aspect to the functional analysis of these lectins in the nucleus. 10.1016/j.biolcel.2003.08.002
An unusual case of desmoplastic melanoma containing an osteoclast-like giant cell-rich nodule. Houang Michelle,Castillo Christine,La Marca Sophie,Combemale Patrick,Wang Qing,Paindavoine Sandrine,Pissaloux Daniel,de la Fouchardiere Arnaud The American Journal of dermatopathology The authors describe a case of a 5 cm mixed desmoplastic melanoma occurring on the cheek of an 88-year-old white woman. The epidermis showed the features of lentigo maligna. Within the dermis, there was a mixed desmoplastic melanoma with 2 components. The first component consisted of infiltrative malignant spindled cells with prominent stromal fibrosis and had the typical appearance of desmoplastic melanoma. The second component was within the deep half of the tumor and consisted of a densely cellular nodule composed of spindled melanocytes admixed with many osteoclast-like giant cells. There was a peripheral neurotropism and tumor invaded bone. The Breslow thickness was 14 mm. On followup, a sacral metastasis was discovered, which had a similar morphology to the deep cellular nodule. Immunohistochemistry of spindled cells both inside and outside the nodule showed S100 positivity with the absence of other melanocytic markers (HMB-45, Melan-A). Smooth muscle actin and p63 were focally positive. The osteoclast-like giant cells expressed CD68 and MiTF. Array comparative genomic hybridization of the typical desmoplastic melanoma region had a flat profile, whereas the cellular osteoclast-like giant cell–rich region displayed important cytogenetic anomalies, some of which have been previously described in melanomas. The main array comparative genomic hybridization findings were confirmed by fluorescence in situ hybridization using specific probes. The differences in morphology and molecular cytogenetics between the 2 areas suggest that these might represent the progression or emergence of a more aggressive clone within the tumor. Subsequent metastatic spread to the bone may be a result of accumulated cytogenetic abnormalities. 10.1097/DAD.0000000000000080
Keratinocyte-specific ablation of protease-activated receptor 2 prevents gingival inflammation and bone loss in a mouse model of periodontal disease. Francis Nidhish,Ayodele Babatunde A,O'Brien-Simpson Neil M,Birchmeier Walter,Pike Robert N,Pagel Charles N,Mackie Eleanor J Cellular microbiology Chronic periodontitis is characterised by gingival inflammation and alveolar bone loss. A major aetiological agent is Porphyromonas gingivalis, which secretes proteases that activate protease-activated receptor 2 (PAR ). PAR expressed on oral keratinocytes is activated by proteases released by P. gingivalis, inducing secretion of interleukin 6 (IL-6), and global knockout of PAR prevents bone loss and inflammation in a periodontal disease model in mice. To test the hypothesis that PAR expressed on gingival keratinocytes is required for periodontal disease pathology, keratinocyte-specific PAR -null mice were generated using K14-Cre targeted deletion of the PAR gene (F2rl1). These mice were subjected to a model of periodontitis involving placement of a ligature around a tooth, combined with P. gingivalis infection ("Lig + Inf"). The intervention caused a significant 44% decrease in alveolar bone volume (assessed by microcomputed tomography) in wildtype (K14-Cre:F2rl1 ), but not littermate keratinocyte-specific PAR -null (K14-Cre:F2rl1 ) mice. Keratinocyte-specific ablation of PAR prevented the significant Lig + Inf-induced increase (2.8-fold) in the number of osteoclasts in alveolar bone and the significant up-regulation (2.4-4-fold) of the inflammatory markers IL-6, IL-1β, interferon-γ, myeloperoxidase, and CD11b in gingival tissue. These data suggest that PAR expressed on oral epithelial cells is a critical regulator of periodontitis-induced bone loss and will help in designing novel therapies with which to treat the disease. 10.1111/cmi.12891
[Update on recent progress in vitamin D research. Vitamin D and bone, mineral metabolism.] Masuyama Ritsuko Clinical calcium Vitamin D endocrine system is required for bone and mineral homeostasis through the active form of vitamin D[1α,25(OH)D]transported to the target organs, where the vitamin D receptor(VDR)is present. The biological significance of 1α,25(OH)D-VDR signalling is regarded not only in classical target of vitamin D involved in calcium and phosphate homeostasis, such as intestine, bone, kidney and parathyroid glands, but also in many other non-classical target cells of vitamin D including skin keratinocytes, pancreatic β cells, cardiomyocytes, T-lymphocytes, bone marrow macrophages, among others. Although 1α,25(OH)D-VDR signalling in classical target organs of vitamin D has been extensively studied, its precise function in these target organs still needs further investigation. CliCa171115251532
A Case of Short Stature and Severe Osteoporosis in a Young Man with Oculocutaneous Albinism: Syndrome or Coincidence? Cureus Oculocutaneous albinism (OCA) is a rare autosomal recessive congenital condition characterized by reduced or absent production of the pigment melanin by melanocytes. The affected individuals have increased susceptibility to sunburn and skin cancers. Osteoporosis is a disease entity characterized by the progressive loss of bone mineral density and the deterioration of bone micro-architecture, leading to an increased risk of developing low-trauma fractures. There are many causes of osteoporosis, ranging from primary to secondary causes. Short stature is defined as height less than two standard deviations below the age-specific and gender-specific mean (less than the 2.5th percentile). There have been rare case reports of individuals with OCA having associated osteoporosis or low bone mineral density and short stature. These cases have also been associated with severe skeletal, neurological, and psychomotor disabilities. This paper presents a case of a young man with OCA and short stature who sustained a low-trauma intertrochanteric fracture to his femur bone and was subsequently diagnosed to have clinically significant osteoporosis. This case report while attempting to review the literature also emphasizes the importance of further research into the prevalence of these clinical features accompanying certain types of OCA and whether they are part of a single syndrome or just coincidental findings. 10.7759/cureus.7817
Effects of human growth hormone in men over 60 years old. Rudman D,Feller A G,Nagraj H S,Gergans G A,Lalitha P Y,Goldberg A F,Schlenker R A,Cohn L,Rudman I W,Mattson D E The New England journal of medicine BACKGROUND:The declining activity of the growth hormone--insulin-like growth factor I (IGF-I) axis with advancing age may contribute to the decrease in lean body mass and the increase in mass of adipose tissue that occur with aging. METHODS:To test this hypothesis, we studied 21 healthy men from 61 to 81 years old who had plasma IGF-I concentrations of less than 350 U per liter during a six-month base-line period and a six-month treatment period that followed. During the treatment period, 12 men (group 1) received approximately 0.03 mg of biosynthetic human growth hormone per kilogram of body weight subcutaneously three times a week, and 9 men (group 2) received no treatment. Plasma IGF-I levels were measured monthly. At the end of each period we measured lean body mass, the mass of adipose tissue, skin thickness (epidermis plus dermis), and bone density at nine skeletal sites. RESULTS:In group 1, the mean plasma IGF-I level rose into the youthful range of 500 to 1500 U per liter during treatment, whereas in group 2 it remained below 350 U per liter. The administration of human growth hormone for six months in group 1 was accompanied by an 8.8 percent increase in lean body mass, a 14.4 percent decrease in adipose-tissue mass, and a 1.6 percent increase in average lumbar vertebral bone density (P less than 0.05 in each instance). Skin thickness increased 7.1 percent (P = 0.07). There was no significant change in the bone density of the radius or proximal femur. In group 2 there was no significant change in lean body mass, the mass of adipose tissue, skin thickness, or bone density during treatment. CONCLUSIONS:Diminished secretion of growth hormone is responsible in part for the decrease of lean body mass, the expansion of adipose-tissue mass, and the thinning of the skin that occur in old age. 10.1056/NEJM199007053230101
Identification and characterization of noncalcemic, tissue-selective, nonsecosteroidal vitamin D receptor modulators. Ma Yanfei,Khalifa Berket,Yee Ying K,Lu Jianfen,Memezawa Ai,Savkur Rajesh S,Yamamoto Yoko,Chintalacharuvu Subba R,Yamaoka Kazuyoshi,Stayrook Keith R,Bramlett Kelli S,Zeng Qing Q,Chandrasekhar Srinivasan,Yu Xiao-Peng,Linebarger Jared H,Iturria Stephen J,Burris Thomas P,Kato Shigeaki,Chin William W,Nagpal Sunil The Journal of clinical investigation Vitamin D receptor (VDR) ligands are therapeutic agents for the treatment of psoriasis, osteoporosis, and secondary hyperparathyroidism. VDR ligands also show immense potential as therapeutic agents for autoimmune diseases and cancers of skin, prostate, colon, and breast as well as leukemia. However, the major side effect of VDR ligands that limits their expanded use and clinical development is hypercalcemia that develops as a result of the action of these compounds mainly on intestine. In order to discover VDR ligands with less hypercalcemia liability, we sought to identify tissue-selective VDR modulators (VDRMs) that act as agonists in some cell types and lack activity in others. Here, we describe LY2108491 and LY2109866 as nonsecosteroidal VDRMs that function as potent agonists in keratinocytes, osteoblasts, and peripheral blood mononuclear cells but show poor activity in intestinal cells. Finally, these nonsecosteroidal VDRMs were less calcemic in vivo, and LY2108491 exhibited more than 270-fold improved therapeutic index over the naturally occurring VDR ligand 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] in an in vivo preclinical surrogate model of psoriasis. 10.1172/JCI25901
Exposing human epithelial cells to zoledronic acid can mediate osteonecrosis of jaw: an in vitro model. Saracino S,Canuto R A,Maggiora M,Oraldi M,Scoletta M,Ciuffreda L,Vandone A M,Carossa S,Mozzati M,Muzio G Journal of oral pathology & medicine : official publication of the International Association of Oral Pathologists and the American Academy of Oral Pathology BACKGROUND:Osteonecrosis of the jaw (ONJ) is a chronic complication of bisphosphonate therapy, mainly when intravenous, in cancer patients with bone metastases and myeloma. Its pathophysiology is not yet fully elucidated; in particular, the molecular/cellular events triggering ONJ remain unclear. This complication could result from the effect of bisphosphonates released from bone into the soft-tissues, or from osteolysis induced by soft-tissues directly exposed to bisphosphonates. This research investigated the possibility that ONJ may be evocated by changes induced in osteoblast activity by factors released by soft-tissue cells exposed to zoledronic acid. METHODS:An 'in vitro' model was used, in which human osteoblast-like MG-63 cells were grown in medium conditioned by human keratinocytes NCTC 2544, exposed or not to zoledronic acid (5 or 50 μM); 5 μM zoledronic acid was also directly administered to MG-63 cells. RESULTS:In NCTC 2544 cells, zoledronic acid decreased proliferation via decreased hydroxy-3-methyl-glutaryl-CoA reductase, suggesting that a decrease in healing capability can occur in case of injury. An increased pro-inflammatory potential was also observed. Osteoblasts grown in medium conditioned in the presence of zoledronic acid showed decreased proliferation and osteogenic properties, and increased ability to induce osteoclast differentiation and inflammatory process. Zoledronic acid directly administered to MG-63 modulated only some parameters and in a lesser extent. CONCLUSIONS:The research evidenced, for the first time, the direct involvement of epithelial cells in zoledronic acid-triggered molecular mechanisms leading to osteonecrosis of the jaw, by modulating both osteoblast and osteoclast properties. 10.1111/j.1600-0714.2012.01173.x
Icariin and icaritin recover UVB-induced photoaging by stimulating Nrf2/ARE and reducing AP-1 and NF-κB signaling pathways: a comparative study on UVB-irradiated human keratinocytes. Hwang Eunson,Lin Pei,Ngo Hien T T,Gao Wei,Wang Yu-Shuai,Yu Hong-Shan,Yi Tae-Hoo Photochemical & photobiological sciences : Official journal of the European Photochemistry Association and the European Society for Photobiology Icariin (ICA) and icaritin (ICT) exhibit many pharmacological functions including anti-osteoporosis, anti-cardiovascular, and anti-cancer activities; however, there are few comprehensive studies that track the detailed effects on UVB-induced photoaging. The recovery effects of ICA and ICT were investigated in UVB-irradiated human keratinocytes (HaCaTs). The results indicated that ICT and ICA showed strong radical scavenging activity, and the reactive oxygen species (ROS) scavenging activity of ICT was superior. UVB-induced matrix metalloproteinase-1 (MMP-1) expression was blocked by ICA via the inhibition of mitogen-activated protein kinase/activator protein 1 (MAPK/AP-1), which directly reduced extracellular matrix (ECM) degradation. ICT activated nuclear factor erythroid 2 related factor 2 (Nrf2) to improve the anti-oxidative stress capacity and suppress nuclear factor-κB (NF-κB) activation, decreasing vascular endothelial growth factor (VEGF) protein, and inflammatory cytokines induced ECM degrading enzyme secretion. Moreover, ICT was more advantageous to improve transforming growth factor beta 1 (TGF-β1) and procollagen type I expression than ICA, promoting the synthesis of collagen. Therefore, ICA and ICT have potential to treat UVB-induced oxidative stress, inflammation and photoaging, and will be posited as a novel strategy to alleviate photodamage. 10.1039/c8pp00174j
Advances in understanding cell interactions in tissue resorption. Relevance to the pathogenesis of periodontal diseases and a new hypothesis. Meikle M C,Heath J K,Reynolds J J Journal of oral pathology Much of the connective tissue degradation that takes place in periodontal diseases is mediated by proteolytic enzymes. Previous studies have focused on the action of proteinases released by invading polymorphonuclear neutrophils and macrophages, and bacterial enzymes. In view of recent work establishing that resident connective tissue cells can be induced by cytokines to bring about the destruction of their own matrix, we propose a new hypothesis. In this we envisage that a critical step is the interaction of bacterial antigens with inflammatory cells, resulting in the production of a cytokine, interleukin-1. Our interpretation of in vitro evidence is that the loss of connective tissue attachment and bone matrix resorption in periodontal diseases is mediated by metalloproteinases such as collagenase and stromelysin released by cells of the periodontium. Such proteolytic destruction can be induced by interleukin-1, whose production may not be dependent on a specific microbial flora but may be triggered by a number of organisms. It is now clear that interleukin-1 has multiple actions on both immune and non-immune cells; these include the induction of lymphocyte differentiation and proliferation and the stimulation of bone and cartilage resorption, and prostaglandin and metalloproteinase synthesis by connective tissues. It seems likely that further knowledge about the production and function of this cytokine will have an increasing impact in many diseases that involve resorption, particularly since interleukin-1-like molecules can be produced by cell types other than monocytes/macrophages, including keratinocytes and fibroblasts. 10.1111/j.1600-0714.1986.tb00616.x
Interleukin 7 is produced by murine and human keratinocytes. Heufler C,Topar G,Grasseger A,Stanzl U,Koch F,Romani N,Namen A E,Schuler G The Journal of experimental medicine Interleukin 7 (IL-7) was originally identified as a growth factor for B cell progenitors, and subsequently has been shown to exert proliferative effects on T cell progenitors and mature peripheral T cells as well. Constitutive IL-7 mRNA expression so far had been demonstrated in bone marrow stromal cell lines, thymus, spleen, and among nonlymphoid tissues in liver and kidney. Here we show that both murine and human keratinocytes express IL-7 mRNA and release IL-7 protein in biologically relevant amounts. The physiological or pathological relevance of keratinocyte-derived IL-7 is presently unknown. Our finding that keratinocytes can produce IL-7 in concert with reports that IL-7 is a growth factor for in vivo primed antigen-specific T cells, as well as for T lymphoma cells suggests, however, that keratinocyte-derived IL-7 is important in the pathogenesis of inflammatory skin diseases and cutaneous T cell lymphoma. 10.1084/jem.178.3.1109
Localization of interleukin-1 in human cholesteatoma. Ahn J M,Huang C C,Abramson M American journal of otolaryngology Recent studies by other investigators have shown that interleukin-1 (IL-1) promotes bone resorption by stimulating various cells. Interleukin-1 not only stimulates collagenase production by fibroblasts and macrophages, but also acts as an osteoclast-activating factor. In this study, IL-1 was localized in human cholesteatoma tissues using both immunoperoxidase and immunofluorescent-staining methods with specific monoclonal antibodies. Highly concentrated IL-1 was found in the epithelial layer and granulation tissue. More specifically, intense staining was seen in basal and spinous cells of the epithelial layer, and in fibroblasts and macrophages of the granulation layer. We also located IL-1 in the normal external ear canal skin; however, the intensity of the staining in the cholesteatoma epithelium was found to be stronger. The presence of IL-1 in the epithelial layer and granulation tissue of the cholesteatoma suggests that IL-1 from the stimulated keratinocytes of the cholesteatoma could be one factor responsible for the markedly increased bone resorption observed in cholesteatoma patients.
The role of sirtuin 1 in osteoblastic differentiation in human periodontal ligament cells. Lee Y-M,Shin S-I,Shin K-S,Lee Y-R,Park B-H,Kim E-C Journal of periodontal research BACKGROUND AND OBJECTIVE:Activation of sirtuin 1 (SIRT1) promotes the differentiation of keratinocytes and mesenchymal stem cells, but inhibits the differentiation of muscle and fat cells. However, the involvement of SIRT1 in the differentiation of human periodontal ligament cells into osteoblast-like cells remains unclear. To identify the role of SIRT1 in human periodontal ligament cells, we measured SIRT1 mRNA and SIRT1 protein levels during the osteoblastic differentiation of human periodontal ligament cells. Additionally, we investigated the effects of overexpressing and underexpressing SIRT1 on the differentiation of human periodontal ligament cells, and the signaling mechanisms involved. MATERIAL AND METHODS:Expression of SIRT1 and osteoblastic differentiation markers was assessed by RT-PCR, real-time PCR, Alizarin red staining and western blotting. RESULTS:Marked upregulation of SIRT1 mRNA and SIRT1 protein was observed in cells grown for 3 d in osteogenic induction medium (OM). Activation of SIRT1 using resveratrol and isonicotinamide stimulated osteoblastic differentiation in a dose-dependent manner, as assessed by the expression of mRNAs encoding alkaline phosphatase, osteopontin, osteocalcin, osterix and Runx2, and induced calcium deposition. In contrast, inhibition of SIRT1 using sirtinol, nicotinamide and gene silencing by RNA interference suppressed mineralization and the expression of osteoblast marker mRNAs. Further mechanistic studies revealed that resveratrol treatment increased the phosphorylation of Akt, adenosine monophosphate kinase (AMPK), Smad 1/5/8 and c-Jun N-terminal kinase, but reduced OM-induced activation of nuclear factor-κB. Conversely, application of sirtinol suppressed the phosphorylation of Akt, AMPK, Smad 1/5/8, p38, ERK and c-Jun N-terminal kinase, and enhanced nuclear factor-κB activity, in OM-stimulated cells. CONCLUSION:These data suggest that SIRT1 is a potent regulator of differentiation of human periodontal ligament cells and may have clinical implications for periodontal bone regeneration. 10.1111/j.1600-0765.2011.01394.x
Leucosceptoside A from Devil's Claw Modulates Psoriasis-like Inflammation via Suppression of the PI3K/AKT Signaling Pathway in Keratinocytes. Koycheva Ivanka K,Mihaylova Liliya V,Todorova Monika N,Balcheva-Sivenova Zhivka P,Alipieva Kalina,Ferrante Claudio,Orlando Giustino,Georgiev Milen I Molecules (Basel, Switzerland) Psoriasis is a chronic inflammatory skin condition characterized by abnormal keratinocyte proliferation and differentiation that is accompanied with dysregulated immune response and abnormal vascularization. Devil's claw ( (Burch.) DC. ex Meisn.) tubers extract has been used both systemically and topically for treatment of chronic inflammatory diseases such as arthritis, osteoporosis, inflammatory bowel disease, among others. However, its potential mechanisms of action against psoriasis remains poorly investigated. The human keratinocyte HaCaT cell line is a well-accepted in vitro model system for inflammatory skin disorders such as psoriasis. The present study involved an exploration of the effect of biotechnologically produced (HP) cell suspension extract and pure phenylethanoid glycosides verbascoside (VER) and leucosceptoside A (LEU) in interferon (IFN)-γ/interleukin (IL)-17A/IL-22-stimulated HaCaT cells as a model of psoriasis-like inflammation. Changes in key inflammatory signaling pathways related to psoriasis development were detected by reverse transcription polymerase chain reaction and western blotting. Treatment with LEU, but not VER and HP extract improved psoriasis-related inflammation via suppression of the PI3K/AKT signaling in IFN-γ/IL-17A/IL-22-stimulated HaCaT cells. Our results suggest that LEU may exhibit therapeutic potential against psoriasis by regulating keratinocyte differentiation through inhibition of the PI3K/AKT pathway. 10.3390/molecules26227014
Concepts in a multiprong approach to photoaging. Draelos Z D Skin therapy letter Photoaging is a multisystem degenerative process that involves the skin and the skin support systems, including the bone, cartilage, and subcutaneous compartments. These structures provide the architectural support for the dermis, epidermis, and stratum corneum. A multiprong approach to photoaging involves reversing the undesirable changes in each of these structures. Dermatologists should become adept at treating all of the visible manifestations of photoaging.
Distribution of EGF and its receptor in growing red deer antler. Barling Peter M,Lai Angela K W,Nicholson Louise F B Cell biology international Autografts of the osteogenic part of early antler buds placed elsewhere on the skull have been shown by others to give rise to an antler at the site of grafting. This antler becomes covered in velvet skin, is shed at the end of the growing season and will regrow the following year. Thus, it can be concluded that the nature of antler velvet skin is primarily determined by the underlying osteogenic antler tissue to which it is attached. We hypothesise that a paracrine mechanism operates here and is central to communication between the antler osseous compartment and the integument. A signalling system comprising epidermal growth factor (EGF) and its receptor (EGFR) is known to be expressed in osteogenic cells and to play an important role in skin development and growth. This system may therefore play a significant role in determining the nature and speed of growth of velvet skin via paracrine signalling from osteogenic tissue. We have used bright-field microscope immunohistochemistry to determine the distribution of EGF and its receptor in developing red deer antler osseous compartment and integument. EGF was localized throughout the epidermis and epidermal appendages, in cells of the mesenchyme, in chondrocytes, and in cells of the osteoblastic lineage, including osteoprogenitor cells, osteoblasts and osteocytes. There was strong evidence supporting nuclear and nucleolar staining in sebaceous glands and in keratinocytes. The EGFR was similarly expressed in mesenchyme, chondrocytes and osteoblasts. In skin, the distribution of the EGFR was more localized, being expressed strongly in the deeper cells of the epidermis but not in superficial layers, and was absent from nuclei of cells of the epidermis and its appendages. We conclude that this signalling system is widely distributed in growing antler in a manner which suggests it is predominantly autocrine. No clear-cut evidence for paracrine signalling pathways for this system in either integument or osseous compartments was found. The pattern of distribution of the EGFR in the integument was similar to that seen by others in adult human skin. By contrast, in developing antler osseocartilage, the patterns of distribution were similar to those seen in rodent fetal bone. We conclude that antler consists of rapidly growing fetal osseocartilage overlayed by mature velvet. 10.1016/j.cellbi.2004.12.004
Lipopolysaccharide concentration and bone resorption in cholesteatoma. Peek F A W,Huisman M A,Berckmans R J,Sturk A,Van Loon J,Grote J J Otology & neurotology : official publication of the American Otological Society, American Neurotology Society [and] European Academy of Otology and Neurotology HYPOTHESIS:There is a relationship between the local lipopolysaccharide (LPS) concentration in cholesteatoma and local bone resorption in chronic otitis media (COM) with cholesteatoma. BACKGROUND:During the past decade, it has become known that the recruitment of osteoclasts is the main causative factor that induces bone destruction in COM with cholesteatoma. Cellular inflammation factors like cytokines may trigger the osteoclast. Sequel to this, LPS is able to up-regulate cytokines. This makes it of interest to study whether the local LPS concentration is related to bone resorption in cholesteatoma. MATERIALS AND METHODS:Twenty-four cholesteatoma samples and control tissue from COM patients without cholesteatoma were collected. During surgery, the degree of bone resorption was established and classified. Retrospectively, the authors checked whether patients had chronic purulent otorrhea. LPS concentration of the tissue samples was measured by the limulus amebocyte lysate test. The one-way analysis of variance test was used to determine the relation between LPS concentration, otorrhea, and local bone resorption. RESULTS:A significantly higher concentration of LPS was measured in samples from patients with cholesteatoma with bone resorption and otorrhea compared with cholesteatoma without bone resorption and control tissue. There were no significant differences between the LPS levels of the different groups of patients with bone resorption. CONCLUSION:It is suggested that LPS is one of the first factors in the cascade of bone resorption in COM with cholesteatoma. 10.1097/00129492-200309000-00002
The effects of 1alpha,25-dihydroxyvitamin D3 on the expression of DNA replication genes. Eelen Guy,Verlinden Lieve,van Camp Mark,van Hummelen Paul,Marchal Kathleen,de Moor Bart,Mathieu Chantal,Carmeliet Geert,Bouillon Roger,Verstuyf Annemieke Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research UNLABELLED:To identify key genes in the antiproliferative action of 1,25(OH)2D3, MC3T3-E1 mouse osteoblasts were subjected to cDNA microarray analyses. Eleven E2F-driven DNA replication genes were downregulated by 1,25(OH)2D3. These results were confirmed by quantitative RT-PCR in different cell types, showing the general nature of this action of 1,25(OH)2D3. INTRODUCTION:1Alpha,25-dihydroxyvitamin D3 [1,25(OH)2D3] has a potent antiproliferative action characterized by a blocked transition from the G1- to the S-phase of the cell cycle. This study aims to identify genes whose expression is markedly altered after 1,25(OH)2D3 treatment in parallel with or preceding the observed G1-arrest. MATERIALS AND METHODS:The cDNA microarray technique was used, and the expression of approximately 4600 genes in MC3T3-E1 mouse osteoblasts was studied 6 and 12 h after treatment with 10(-8) M 1,25(OH)2D3. Quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) analyses were performed on MC3T3-E1 cells and on wildtype and vitamin D receptor (VDR) knockout primary murine epidermal keratinocytes (VDRwt MEKs, VDR-/- MEKs) and murine mammary tumor cells (GR) to confirm the microarray data. RESULTS AND CONCLUSIONS:After 12 h of treatment, in parallel with the 1,25(OH)2D3-induced G1 arrest, a particular set of DNA replication genes including a cell division cycle 6 homolog, a DNA polymerase alpha subunit, proliferating cell nuclear antigen, two DNA polymerase delta subunits, and flap-structure specific endonuclease 1, was downregulated at least 2-fold. These genes are known targets of the E2F family of transcription factors, which are probably the central mediators of this action of 1,25(OH)2D3. Indeed, as shown by transfection assays with an E2F reporter construct, 12- and 24-h treatment of MC3T3-E1 cells with 1,25(OH)2D3 reduced E2F activity by 49% and 73%, respectively. Quantitative RT-PCR analyses confirmed the downregulation of these DNA replication genes by 1,25(OH)2D3 in MC3T3-E1, GR, and VDRwt MEKs cells, but not in VDR-/- MEKs cells, showing that this 1,25(OH)2D3-driven antiproliferative action is of a general nature and depends on a functional VDR. 10.1359/JBMR.0301204
Chronic skin inflammation leads to bone loss by IL-17-mediated inhibition of Wnt signaling in osteoblasts. Uluçkan Özge,Jimenez Maria,Karbach Susanne,Jeschke Anke,Graña Osvaldo,Keller Johannes,Busse Björn,Croxford Andrew L,Finzel Stephanie,Koenders Marije,van den Berg Wim,Schinke Thorsten,Amling Michael,Waisman Ari,Schett Georg,Wagner Erwin F Science translational medicine Inflammation has important roles in tissue regeneration, autoimmunity, and cancer. Different inflammatory stimuli can lead to bone loss by mechanisms that are not well understood. We show that skin inflammation induces bone loss in mice and humans. In psoriasis, one of the prototypic IL-17A-mediated inflammatory human skin diseases, low bone formation and bone loss correlated with increased serum IL-17A levels. Similarly, in two mouse models with chronic IL-17A-mediated skin inflammation,K14-IL17A(ind)andJunB(Δep), strong inhibition of bone formation was observed, different from classical inflammatory bone loss where osteoclast activation leads to bone degradation. We show that under inflammatory conditions, skin-resident cells such as keratinocytes, γδ T cells, and innate lymphoid cells were able to express IL-17A, which acted systemically to inhibit osteoblast and osteocyte function by a mechanism involving Wnt signaling. IL-17A led to decreased Wnt signaling in vitro, and importantly, pharmacological blockade of IL-17A rescued Wnt target gene expression and bone formation in vivo. These data provide a mechanism where IL-17A affects bone formation by regulating Wnt signaling in osteoblasts and osteocytes. This study suggests that using IL-17A blocking agents in psoriasis could be beneficial against bone loss in these patients. 10.1126/scitranslmed.aad8996
IL-17A gene transfer induces bone loss and epidermal hyperplasia associated with psoriatic arthritis. Adamopoulos Iannis E,Suzuki Erika,Chao Cheng-Chi,Gorman Dan,Adda Sarvesh,Maverakis Emanual,Zarbalis Konstantinos,Geissler Richard,Asio Agelio,Blumenschein Wendy M,Mcclanahan Terrill,De Waal Malefyt Rene,Gershwin M Eric,Bowman Edward P Annals of the rheumatic diseases BACKGROUND:Psoriatic arthritis (PsA) is a chronic inflammatory disease characterised by clinical features that include bone loss and epidermal hyperplasia. Aberrant cytokine expression has been linked to joint and skin pathology; however, it is unclear which cytokines are critical for disease initiation. Interleukin 17A (IL-17A) participates in many pathological immune responses; however, its role in PsA has not been fully elucidated. OBJECTIVE:To determine the role of IL-17A in epidermal hyperplasia and bone destruction associated with psoriatic arthritis. DESIGN:An in vivo gene transfer approach was used to investigate the role of IL-17A in animal models of inflammatory (collagen-induced arthritis) and non-inflammatory (receptor activator of NF-κB ligand (RANKL)-gene transfer) bone loss. RESULTS:IL-17A gene transfer induced the expansion of IL-17RA(+)CD11b(+)Gr1(low) osteoclast precursors and a concomitant elevation of biomarkers indicative of bone resorption. This occurred at a time preceding noticeable joint inflammation, suggesting that IL-17A is critical for the induction of pathological bone resorption through direct activation of osteoclast precursors. Moreover, IL-17A induced a second myeloid population CD11b(+)Gr1(high) neutrophil-like cells, which was associated with cutaneous pathology including epidermal hyperplasia, parakeratosis and Munro's microabscesses formation. CONCLUSIONS:Collectively, these data support that IL-17A can play a key role in the pathogenesis of inflammation-associated arthritis and/or skin disease, as observed in PsA. 10.1136/annrheumdis-2013-204782
Bone morphogenetic protein signaling promotes morphogenesis of blood vessels, wound epidermis, and actinotrichia during fin regeneration in zebrafish. Thorimbert Valentine,König Désirée,Marro Jan,Ruggiero Florence,Jaźwińska Anna FASEB journal : official publication of the Federation of American Societies for Experimental Biology Zebrafish fin regeneration involves initial formation of the wound epidermis and the blastema, followed by tissue morphogenesis. The mechanisms coordinating differentiation of distinct tissues of the regenerate are poorly understood. Here, we applied pharmacologic and transgenic approaches to address the role of bone morphogenetic protein (BMP) signaling during fin restoration. To map the BMP transcriptional activity, we analyzed the expression of the evolutionarily conserved direct phospho-Smad1 target gene, id1, and its homologs id2a and id3. This analysis revealed the BMP activity in the distal blastema, wound epidermis, osteoblasts, and blood vessels of the regenerate. Blocking the BMP function with a selective chemical inhibitor of BMP type I receptors, DMH1, suppressed id1 and id3 expression and arrested regeneration after blastema formation. We identified several previously uncharacterized functions of BMP during fin regeneration. Specifically, BMP signaling is required for remodeling of plexus into structured blood vessels in the rapidly growing regenerate. It organizes the wound epithelium by triggering wnt5b expression and promoting Collagen XIV-A deposition into the basement membrane. BMP represents the first known signaling that induces actinotrichia formation in the regenerate. Our data reveal a multifaceted role of BMP for coordinated morphogenesis of distinct tissues during regeneration of a complex vertebrate appendage. 10.1096/fj.15-272955
HB-EGF expression as a potential biomarker of acquired middle ear cholesteatoma. Xie Shumin,Wang Xiaoli,Ren Hongmiao,Liu Xiaoyu,Ren Jihao,Liu Wei Acta oto-laryngologica CONCLUSIONS:The heparin-binding epidermal growth factor-like growth factor (HB-EGF) plays an essential role in the development and invasiveness of cholesteatoma. This study may help to realize the molecular mechanisms underlying the pathogenesis of cholesteatoma and make HB-EGF a promising target for drug intervention of cholesteatoma. OBJECTIVE:To detect HB-EGF expression in human surgical specimens of acquired middle ear cholesteatoma and analyze its functional role as a regulator of epithelial keratinocytes hyperproliferation. METHODS:A total of 34 patients who underwent surgical treatment for middle ear cholesteatoma were recruited in the study. The mRNA and protein expression of HB-EGF in middle ear cholesteatoma tissues and normal postauricular skin tissues was investigated by real-time quantitative reverse-transcription-polymerase chain reaction (RT-qPCR), immunohistochemical staining, and western blot. The correlation between bone resorption degree and HB-EGF expression was also analyzed. RESULTS:On average, compared with normal postauricular skin, expression of HB-EGF mRNA in the cholesteatoma epithelium was significantly elevated 2.41-fold by RT-qPCR, and HB-EGF protein significantly upregulated 2.32-fold by western blot. Positive HB-EGF immunostaining observed in the basal and suprabasal layers of cholesteatoma epithelium was significantly stronger than in normal postauricular skin. Meanwhile, an obviously positive correlation between HB-EGF protein expression and bone resorption degree was discovered. 10.1080/00016489.2017.1284343
Shh promotes direct interactions between epidermal cells and osteoblast progenitors to shape regenerated zebrafish bone. Armstrong Benjamin E,Henner Astra,Stewart Scott,Stankunas Kryn Development (Cambridge, England) Zebrafish innately regenerate amputated fins by mechanisms that expand and precisely position injury-induced progenitor cells to re-form tissue of the original size and pattern. For example, cell signaling networks direct osteoblast progenitors (pObs) to rebuild thin cylindrical bony rays with a stereotypical branched morphology. Hedgehog/Smoothened (Hh/Smo) signaling has been variably proposed to stimulate overall fin regenerative outgrowth or promote ray branching. Using a photoconvertible reporter, we resolve active Hh/Smo output to a narrow distal regenerate zone comprising pObs and adjacent motile basal epidermal cells. This Hh/Smo activity is driven by epidermal Sonic hedgehog a (Shha) rather than Ob-derived Indian hedgehog a (Ihha), which nevertheless functions atypically to support bone maturation. Using BMS-833923, a uniquely effective Smo inhibitor, and high-resolution imaging, we show that Shha/Smo is functionally dedicated to ray branching during fin regeneration. Hh/Smo activation enables transiently divided clusters of Shha-expressing epidermis to escort pObs into similarly split groups. This co-movement likely depends on epidermal cellular protrusions that directly contact pObs only where an otherwise occluding basement membrane remains incompletely assembled. Progressively separated pObs pools then continue regenerating independently to collectively re-form a now branched skeletal structure. 10.1242/dev.143792
Osteoporosis and the metabolites of vitamin D. DeLuca H F Metabolism: clinical and experimental Vitamin D is metabolized by sequential steps in the liver and kidney to its active form, a process that is strongly feedback-regulated. In old age, the activity of the enzyme, 25-hydroxyvitamin D 1 hydroxylase, which produces the vitamin D hormone, is diminished. The activities of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) extend beyond increasing intestinal absorption of calcium. The vitamin D hormone (or its analogs) is useful in the treatment of osteoporosis because it not only stimulates intestinal calcium absorption, but also is required for the stimulation of osteoblasts and many other cells in the body. Recent work demonstrates that it is possible to chemically synthesize analogs selective for specific actions of the vitamin D hormone, especially in inducing differentiation of promyelocytes and keratinocytes.
Height and bone mineral density are associated with naevus count supporting the importance of growth in melanoma susceptibility. Ribero Simone,Glass Daniel,Aviv Abraham,Spector Timothy David,Bataille Veronique PloS one Naevus count is the strongest risk factor for melanoma. Body Mass Index (BMI) has been linked to melanoma risk. In this study, we investigate the link between naevus count and height, weight and bone mineral density (BMD) in the TwinsUK cohort (N = 2119). In addition we adjusted for leucocyte telomere length (LTL) as LTL is linked to both BMD and naevus count. Naevus count was positively associated with height (p = 0.001) but not with weight (p = 0.187) despite adjusting for age and twin relatedness. This suggests that the previously reported melanoma association with BMI may be explained by height alone. Further adjustment for LTL did not affect the significance of the association between height and naevus count so LTL does not fully explain these results. BMD was associated with naevus count at the spine (coeff 18.9, p = 0.01), hip (coeff = 18.9, p = 0.03) and forearm (coeff = 32.7, p = 0.06) despite adjusting for age, twin relatedness, weight, height and LTL. This large study in healthy individuals shows that growth via height, probably in early life, and bone mass are risk factors for melanoma via increased naevus count. The link between these two phenotypes may possibly be explained by telomere biology, differentiation genes from the neural crests but also other yet unknown factors which may influence both bones and melanocytes biology. 10.1371/journal.pone.0116863
Fabricating Composite Cell Sheets for Wound Healing: Cell Sheets Based on the Communication Between BMSCs and HFSCs Facilitate Full-Thickness Cutaneous Wound Healing. Tissue engineering and regenerative medicine BACKGROUND:Insufficient angiogenesis and the lack of skin appendages are critical challenges in cutaneous wound healing. Stem cell-fabricated cell sheets have become a promising strategy, but cell sheets constructed by a single cell type are inadequate to provide a comprehensive proregenerative microenvironment for wound tissue. METHODS:Based on the communication between cells, in this study, bone marrow mesenchymal stem cells (BMSCs) and hair follicle stem cells (HFSCs) were cocultured to fabricate a composite cell sheet (H/M-CS) for the treatment of full-thickness skin wounds in mice. RESULTS:Experiments confirmed that there is cell-cell communication between BMSCs and HFSCs, which enhances the cell proliferation and migration abilities of both cell types. Cell-cell talk also upregulates the gene expression of pro-angiogenic-related cytokines in BMSCs and pro-hair follicle-related cytokines in HFSCs, as well as causing changes in the properties of secreted extracellular matrix components. CONCLUSIONS:Therefore, the composite cell sheet is more conducive for cutaneous wound healing and promoting the regeneration of blood vessels and hair follicles. 10.1007/s13770-023-00614-0
Establishment and validation of an in vitro co-culture model for oral cell lines using human PBMC-derived osteoclasts, osteoblasts, fibroblasts and keratinocytes. Steller Daniel,Scheibert Alexandra,Sturmheit Tabea,Hakim Samer G Scientific reports Indirect co-culture models with osteoclasts including oral cell lines may be influenced by M-CSF and RANKL in the common cell medium. Therefore, we investigated the viability and proliferation of osteoblasts (OB), fibroblasts (FB) and oral keratinocytes (OK) under stratified medium modification and assessed the differentiation of osteoclasts in each co-culture. The impact of M-CSF and RANKL in the common OC co-culture was assessed for OB, FB and OK via MTT assay via DAPI control. The multinuclearity and function of OC were evaluated by light microscopy, DAPI staining, resorption assay and FACS analysis. The PBMC showed the highest differentiation into OC after an incubation period of 7 days. Furthermore, co-culture with OB enhanced the number of differentiated multinucleated OC in comparison with monoculture, whereas co-culture with OK decreased PBMC multinuclearity and OC differentiation. FB did not influence the number of differentiated OC in a co-culture. RANKL and M-CSF reduction had no impact on OC differentiation in co-culture with FB or OB, whereas this medium modification for OK attenuated PBMC multinuclearity and OC differentiation in all approaches. Supplementation of RANKL and M-CSF can be modified for a co-culture of PBMC with FB or OB without disturbing OC differentiation. Thus, pathogenic processes of bone remodelling involving OB, OC, FB and OK in the oral cavity can be investigated thoroughly. 10.1038/s41598-020-73941-0
Interactions between microenvironment and cancer cells in two animal models of bone metastasis. Blouin S,Baslé M F,Chappard D British journal of cancer The preferential proliferation of cancer cells in the bone microenvironment is poorly characterised. Expression pattern of bone marrow and other organ microenvironment in contact with osteolytic (Walker W256) and osteoblastic (MatLyLu MLL) metastases were investigated. Fisher and Copenhagen rats received, respectively, W256 and MLL cells injection. Bone and soft tissues were analysed by immunochemistry for DKK1, cathepsin K, RANKL, MCSF or IL6 expression. Tartrate-resistant acid phosphatase (TRAcP)-positive cells were detected by a histoenzymatic technique. In bone, expressions of MCSF and DKK1 were shown in stromal cells of the bone marrow, in contact with metastatic foci of both tumours. Many stromal cells were found RANKL positive in the vicinity of the tumours. Cells expressing cathepsin K and multinucleated TRAcP+ cells were found in direct contact with trabeculae but also in bone marrow spaces near metastatic cells. In extraosseous tumours, cells in contact with malignant cells did not expressed DKK1, MCSF, cathepsin K and IL6. Some RANKL+ cells were found in the periphery of subcutaneous tumours but may represent Langerhans cells. Abnormal presence of TRAcP+ cells was never observed in the vicinity of malignant cells. Interaction between stromal and cancer cells induces the expression on the formers of characteristics leading to osteoclastogenesis only in the bone microenvironment. 10.1038/sj.bjc.6604238
A regulatory pathway involving retinoic acid and calcineurin demarcates and maintains joint cells and osteoblasts in regenerating fin. McMillan Stephanie C,Zhang Jing,Phan Hue-Eileen,Jeradi Shirine,Probst Leona,Hammerschmidt Matthias,Akimenko Marie-Andrée Development (Cambridge, England) During zebrafish fin regeneration, blastema cells lining the epidermis differentiate into osteoblasts and joint cells to reconstruct the segmented bony rays. We show that osteoblasts and joint cells originate from a common cell lineage, but are committed to different cell fates. Pre-osteoblasts expressing commit to the osteoblast lineage upon expressing , whereas the strong upregulation of correlates with a commitment to a joint cell type. In the distal regenerate, , and are sequentially upregulated at regular intervals to define the newly identified presumptive joint cells. Presumptive joint cells mature into joint-forming cells, a distinct cell cluster that maintains the expression of these factors. Analysis of null mutants reveals that is acting upstream of and downstream of or in parallel with Calcineurin activity, potentially through the inhibition of retinoic acid signaling, regulates , and expression during joint formation. Furthermore, retinoic acid treatment induces osteoblast differentiation in mature joint cells, leading to ectopic bone deposition in joint regions. Overall, our data reveal a novel regulatory pathway essential for joint formation in the regenerating fin. 10.1242/dev.161158
Keratinocytes-derived exosomal miRNA regulates osteoclast differentiation in middle ear cholesteatoma. Gong NingYue,Zhu Weili,Xu Runtong,Teng Zhenxiao,Deng Chang,Zhou He,Xia Ming,Zhao Miaoqing Biochemical and biophysical research communications The occurrence and development of osteoclasts can directly affect the severity of bone destruction in middle ear cholesteatoma. At the same time, cell communication between keratinocytes and fibroblasts can stimulate osteoclast differentiation. However, the molecular mechanism of osteoclast differentiation in cholesteatoma is still poorly understood. In this study, we try to isolate the exosomes of keratinocytes from patients with middle ear cholesteatoma, and explore the effects of keratinocyte-derived exosomes (Ker-Exo) on osteoclast differentiation by co-culturing Ker-Exo with fibroblasts and osteoclast precursor cells. As a result, we confirmed that Ker-Exo primed fibroblasts can up-regulate the expression of RANKL and promote osteoclast differentiation. We revealed that the effect of Ker-Exo depened on its miRNA-17 conponent. Analysis confirmed that miRNA-17 was down-regulated in Ker-Exo, and they can increase RANKL level in fibroblasts, thus promoting the differentiation of osteoclasts. In conclusions, we provide evidence that exosomes miRNA-17 secreted by keratinocytes in patients with middle ear cholesteatoma can up-regulate the expression of RANKL in fibroblasts and induce osteoclast differentiation. 10.1016/j.bbrc.2020.02.058
Cocultivation of human oral keratinocytes and human osteoblast-like cells. Glaum Ricarda,Wiedmann-Al-Ahmad Margit Methods in molecular biology (Clifton, N.J.) Head and neck reconstruction transplants often require a bony structure but also tissue for the intraoral lining. This is why oral keratinocytes and osteoblast-like cells are essential cell types for combined tissue engineered transplants for defects in the field of craniomaxillofacial surgery. Therefore, we isolated oral keratinocytes and osteoblast-like cells from human tissue samples and cocultivated both cell types on the same carrier. Cell proliferation and morphological analysis showed that the contemporaneous cultivation of human oral keratinocytes and human osteoblast-like cells is possible.The successful in vitro cocultivation of hard and soft tissue derived cells on the same carrier will be an important advancement for developing hard and soft tissue reconstruction therapies especially in the oral cavity. 10.1007/978-1-62703-128-8_27
Solanum nigrum Linne improves DNCB‑induced atopic dermatitis‑like skin disease in BALB/c mice. Hong Sooyeon,Lee Bina,Kim Jae-Hyun,Kim Eun-Young,Kim Minsun,Kwon Boguen,Cho Hye-Rin,Sohn Youngjoo,Jung Hyuk-Sang Molecular medicine reports The present study aimed to investigate the effects of Solanum nigrum Linne (SNL) in a model of 1‑chloro‑2,4‑dinitrobenzene (DNCB)‑induced atopic dermatitis (AD) and in TNF‑α/IFN‑γ‑stimulated HaCaT cells. AD is a chronic inflammatory skin disease and is characterized by erythema, edema, increased pruritus and eczema. Steroids are most commonly used for anti‑inflammatory therapy; however, their long‑term use is limited due to side‑effects, such as osteoporosis, brittle skin, muscle weaknesses and diabetes. Therefore, patients with AD require alternative treatment strategies. In previous studies, SNL has been reported to be effective against oxidants and cancer. However, to the best of our knowledge, the effects of SNL on AD have not yet been investigated. The present study examined the effects of SNL ethanol extract on a model of DNCB induced AD and on TNF‑α/IFN‑γ‑stimulated HaCaT cells. The skin tissue was sectioned to measure the thicknesses of the epidermis and dermis, as well as the numbers of eosinophils, mast cells and CD8 infiltration by H&E, toluidine blue, Masson's trichrome and IHC staining. ELISA was performed using serum to measure IgE levels. The present study also examined the expression of various inflammatory cytokines, MAPK and NF‑κB in TNF‑α/IFN‑γ‑stimulated HaCaT cells. SNL significantly reduced the levels of cytokines released from HaCaT cells stimulated with TNF‑α/IFN‑γ. SNL also significantly reduced the levels of p‑p38 at 30 min and significantly reduced the activation of NF‑κB in a time course experiment. In addition, SNL significantly reduced the level of serum IgE and dermal thickness and the infiltration of mast cells and CD8 in the BALB/c mouse model of DNCB‑induced AD. The results of the current study suggest that SNL exerts a suppressive effect on pro‑inflammatory cytokines in vitro and in vivo through the regulation of the immune system. 10.3892/mmr.2020.11381
Modulation of growth factor/cytokine synthesis and signaling by 1alpha,25-dihydroxyvitamin D(3): implications in cell growth and differentiation. Gurlek Alper,Pittelkow Mark R,Kumar Rajiv Endocrine reviews Distinct from its classic functions in the regulation of calcium and phosphorus metabolism as a systemic hormone, 1alpha,25-dihydroxyvitamin D(3) [1alpha,25(OH)(2)D(3)] is involved in the local control and regulation of cellular growth and differentiation in various tissues, including epidermis (keratinocytes) and bone (osteoblasts and osteoclasts). In this review, the impact of 1alpha,25(OH)(2)D(3) on growth factor/cytokine synthesis and signaling is discussed, particularly as it pertains to bone cells and keratinocytes. 1alpha,25(OH)(2)D(3) not only regulates growth factor/cytokine synthesis but may also alter growth factor signaling. Recently discovered examples for such interactions are the interactions between the vitamin D receptor and the mothers against decapentaplegic-related proteins that function downstream of TGFbeta receptors. Inhibitory effects of 1alpha,25(OH)(2)D(3) on keratinocytes through TGFbeta activation and IL-1alpha, IL-6, and IL-8 suppression may provide a rationale for its beneficial effects in the treatment of hyperproliferative skin disorders, whereas stimulatory effects through the epidermal growth factor-related family members and platelet-derived growth factor may be operative in its beneficial effects in skin atrophy and wound healing. Modulation of cytokines and growth factors by 1alpha,25(OH)(2)D(3) during bone remodeling plays an important role in the coupling of osteoblastic bone formation with osteoclastic resorption to maintain bone mass. 10.1210/er.2001-0044
Intercellular Communication between Keratinocytes and Fibroblasts Induces Local Osteoclast Differentiation: a Mechanism Underlying Cholesteatoma-Induced Bone Destruction. Iwamoto Yoriko,Nishikawa Keizo,Imai Ryusuke,Furuya Masayuki,Uenaka Maki,Ohta Yumi,Morihana Tetsuo,Itoi-Ochi Saori,Penninger Josef M,Katayama Ichiro,Inohara Hidenori,Ishii Masaru Molecular and cellular biology Bone homeostasis is maintained by a balance in activity between bone-resorbing osteoclasts and bone-forming osteoblasts. Shifting the balance toward bone resorption causes osteolytic bone diseases such as rheumatoid arthritis and periodontitis. Osteoclast differentiation is regulated by receptor activator of nuclear factor κB ligand (RANKL), which, under some pathological conditions, is produced by T and B lymphocytes and synoviocytes. However, the mechanism underlying bone destruction in other diseases is little understood. Bone destruction caused by cholesteatoma, an epidermal cyst in the middle ear resulting from hyperproliferation of keratinizing squamous epithelium, can lead to lethal complications. In this study, we succeeded in generating a model for cholesteatoma, epidermal cyst-like tissue, which has the potential for inducing osteoclastogenesis in mice. Furthermore, an in vitro coculture system composed of keratinocytes, fibroblasts, and osteoclast precursors was used to demonstrate that keratinocytes stimulate osteoclast differentiation through the induction of RANKL in fibroblasts. Thus, this study demonstrates that intercellular communication between keratinocytes and fibroblasts is involved in the differentiation and function of osteoclasts, which may provide the molecular basis of a new therapeutic strategy for cholesteatoma-induced bone destruction. 10.1128/MCB.01028-15
Cathepsin K expression is increased in oral lichen planus. Siponen Maria,Bitu Carolina Cavalcante,Al-Samadi Ahmed,Nieminen Pentti,Salo Tuula Journal of oral pathology & medicine : official publication of the International Association of Oral Pathologists and the American Academy of Oral Pathology BACKGROUND:Oral lichen planus (OLP) is an idiopathic T-cell-mediated mucosal inflammatory disease. Cathepsin K (Cat K) is one of the lysosomal cysteine proteases. It is involved in many pathological conditions, including osteoporosis and cancer. The expression and role of Cat K in OLP are unknown. METHODS:Twenty-five oral mucosal specimens diagnosed histopathologically as OLP and fourteen healthy controls (HC) were used to study the immunohistochemical (IHC) expression of Cat K. Colocalization of Cat K with CD1a, Melan-A, CD68, CD45, mast cell tryptase (MCT), and Toll-like receptors (TLRs) 4 and 9 were studied using double IHC and/or immunofluorescence (IF) staining. Expression of Cat K was also evaluated in OLP tissue samples before and after topical tacrolimus treatment. RESULTS:Cat K was expressed in a higher percentage of cells in the epithelial zone, and the staining intensity was stronger in the stroma in OLP compared to controls (P < 0.001). In OLP, Cat K was present mostly in melanocytes and macrophages and sporadically in basal keratinocytes, endothelial cells, and extracellularly. Cat K was found also in some fibroblasts in HC and OLP samples. Coexpression of Cat K and TLRs 4 and 9 was seen in some dendritic cells (presumably melanocytes) and macrophages. In OLP, tacrolimus treatment reduced the expression of Cat K in the epithelium but increased it in the stroma. CONCLUSIONS:These results suggest that Cat K is involved in the pathogenesis of OLP. Cat K possibly takes part in the modulation of matrix molecules and cellular receptors. 10.1111/jop.12446
Possible involvement of CXCR3-CXCR6 + CD4 + T cells in Langerhans cell histiocytosis. Journal of bone and mineral metabolism INTRODUCTION:Langerhans cell histiocytosis (LCH) is a condition characterized by proliferation of Langerhans cells and wide-range pathologies, ranging from single granulomatous lesions to multi-organ involvement, associated with tissue destruction. LCH pathogenesis remains obscure although association with interleukin (IL)-17A has been reported. We report here a case that illustrates the potential pathogenic role of helper T17 (Th17) cells in LCH-related bone destruction. MATERIALS AND METHODS:The patient was a 66-year-old woman. The clinical course included craniectomy and bone mass excision in X-9, diagnosis of LCH confirmed by histopathology, followed by 26-month chemotherapy. In August X, the patient was diagnosed with complete central diabetes insipidus. Symptoms improved after treatment with desmopressin. Pituitary magnetic resonance imaging showed swelling extending from the suprasellar region to the pituitary stalk, suggestive of LCH recurrence. This was followed by chemotherapy combined with mercaptopurine hydrate.  RESULTS: Subsequent peripheral blood lymphocyte analysis showed marked increase in activated Th17 cells (CXCR3CXCR6 CD4 T cells). Double staining for CD4 and IL-17 by immunofluorescence of pathological tissue samples obtained during temporal bone mass excision, which confirmed the diagnosis of LCH in X-9, showed areas of combined presence of CD4-positive cells and IL-17-positive cells. Chemotherapy resulted in size reduction of the pituitary lesion and decrease in peripheral blood-activated Th17 cells. CONCLUSIONS:We found abundant peripheral blood-activated Th17 cells and high percentages of IL-17-producing cells in osteolytic bone lesions in LCH. This finding, together with the decrease in peripheral blood-activated Th17 cells following chemotherapy, suggests the potential involvement of activated Th17 cells in LCH-related osteolysis. 10.1007/s00774-022-01397-5
Malignant Melanoma With Osteoclast-Like Differentiation. Wasserman Jason K,Sekhon Harmanjatinder S,Ayroud Yasmine International journal of surgical pathology Osteoclast-like giant cells are frequently encountered in nonskeletal malignancies; however, the evidence to date suggests that they represent a tissue response to the lesion rather than neoplastic differentiation. We describe a case of metastatic melanoma demonstrating osteoclast-like differentiation in the lung. The lung nodule was diagnosed as a metastatic melanoma by histological features and confirmed by immunohistochemistry. Resection specimen showed numerous multinucleated giant cells exhibiting osteoclast-like morphology dispersed throughout the lesion. Both the neoplastic melanocytes and giant cells were reactive for HMB-45, Melan-A, and S100. In addition, the multinucleated neoplastic giant cells were also reactive for the monocyte/macrophage lineage markers CD68 and CD163, and alkaline phosphatase, an enzyme present in normal osteoclasts. The neoplastic melanocytes and the multinucleated neoplastic giant cells were also reactive for microphthalmia-associated transcription factor, a protein required for the development of both melanocytes and osteoclasts. Collectively, a co-expression of monocyte/macrophage markers along with melanocytic markers and alkaline phosphatase in the multinucleated neoplastic giant cells in metastatic melanoma suggest that malignant melanocytes are capable of differentiating into osteoclast-like cells and consequently aid invasion into various structures and eliciting the aggressive behavior. 10.1177/1066896915592016
Benzophenone-3 and benzophenone-8 exhibit obesogenic activity via peroxisome proliferator-activated receptor γ pathway. Shin Jeayoung C,Lee Eunyoung,An Seungchan,Jin Sun Hee,Ha Jaehyoun,Choi Won Jun,Noh Minsoo Toxicology in vitro : an international journal published in association with BIBRA Benzophenone-3 (BP-3) and benzopenone-8 (BP-8) are commonly used ultraviolet (UV) filter ingredients in diverse sunscreen products. Recently, the obesogenic activity of avobenzone, a long wave UV A filter, was elucidated in the adipogenesis model of human bone marrow mesenchymal stem cells (hBM-MSCs). In this study, the obesogenic potentials of BP-3 and BP-8 were investigated because of their chemical similarity to avobenzone. During the adipogenesis in hBM-MSCs, BP-3 and BP-8 (EC, 25.05 and 43.20 μM, respectively) potently promoted adiponectin secretion than avobenzone (EC, 72.69 μM). In target identification, both BP-3 and BP-8 directly bound to peroxisome proliferator-activated receptor γ (PPARγ), which was associated with the recruitment of steroid receptor coactivator-2 (SRC-2). BP-3 functioned as a PPARγ full agonist whereas BP-8 was a PPARγ partial agonist. In addition, BP-3 and BP-8 significantly increased the gene transcription of PPARα, PPARγ, and major lipid metabolism-associated enzymes in human epidermal keratinocytes, a major target site of UV filters in human skin. This study suggests that BP-3 and BP-8 are obesogenic environmental chemicals similar to phthalates, bisphenols, and organotins. 10.1016/j.tiv.2020.104886
Inflammatory Skin-Derived Cytokines Accelerate Osteoporosis in Mice with Persistent Skin Inflammation. Mizutani Kento,Isono Kana,Matsushima Yoshiaki,Okada Karin,Umaoka Ai,Iida Shohei,Habe Koji,Hagimori Kohei,Yamazaki Hidetoshi,Yamanaka Keiichi International journal of molecular sciences Secondary osteoporosis can also be caused by chronic inflammatory skin disease as well as rheumatoid arthritis or inflammatory bowel disease. However, the exact role of osteoporosis in inflammatory skin conditions has not been elucidated. Using a mouse model of dermatitis, we investigated the pathophysiology of osteoporosis in inflammatory skin conditions and the therapeutic impact of osteoporosis medication on inflammatory skin disease. We employed model mice of spontaneous skin inflammation, specifically overexpressing human caspase-1 in the epidermis. Bone density and the expression of various mRNAs in the femur were examined by micro CT and RT-PCR. The effects of minodronate and anti-RANKL antibody on bone structure, histology, and femur blood flow were studied. The mouse model of skin inflammation showed a marked decrease in bone density compared to wild-type littermates with abnormalities in both bone resorption and formation. Minodronate improved bone density by decreasing osteoclasts, but anti-RANKL antibody did not improve. In the dermatitis model, the blood flow in the bone marrow was decreased, and minodronate restored this parameter. A model of persistent dermatitis exhibited marked osteoporosis, but the impact of chronic dermatitis on osteoporosis has not been thoroughly investigated. We should explore the pathogenesis of osteoporosis in skin inflammatory diseases. 10.3390/ijms21103620
NMDA Receptor Hypofunction in the Aging-Associated Malfunction of Peripheral Tissue. Rivera-Villaseñor Angélica,Higinio-Rodríguez Frida,Nava-Gómez Laura,Vázquez-Prieto Bárbara,Calero-Vargas Isnarhazni,Olivares-Moreno Rafael,López-Hidalgo Mónica Frontiers in physiology Glutamatergic transmission through NMDA receptors (NMDARs) is important for the function of peripheral tissues. In the bone, NMDARs and its co-agonist, D-serine participate in all the phases of the remodeling. In the vasculature, NMDARs exerts a tonic vasodilation decreasing blood perfusion in the and the filtration rate in the renal glomerulus. NMDARs are relevant for the skin turnover regulating the proliferation and differentiation of keratinocytes and the formation of the cornified envelope (CE). The interference with NMDAR function in the skin leads to a slow turnover and repair. As occurs with the brain and cognitive functions, the manifestations of a hypofunction of NMDARs resembles those observed during aging. This raises the question if the deterioration of the glomerular vasculature, the bone remodeling and the skin turnover associated with age could be related with a hypofunction of NMDARs. Furthermore, the interference of D-serine and the effects of its supplementation on these tissues, suggest that a decrease of D-serine could account for this hypofunction pointing out D-serine as a potential therapeutic target to reduce or even prevent the detriment of the peripheral tissue associated with aging. 10.3389/fphys.2021.687121
[The research progress of keratin's roles in the pathology of middle ear cholesteatoma]. Feng Y S,Si Y,Zhang Z G Zhonghua er bi yan hou tou jing wai ke za zhi = Chinese journal of otorhinolaryngology head and neck surgery Keratin (K) is the main component of the epithelial cell mesenchymal cytoskeleton, which protects the integrity of epithelial cells and maintains the function of normal epithelial cells. The expression of keratin affects epidermal proliferation and differentiation, and so as to be used as a marker for proliferation, differentiation and migration of keratinocytes. Middle ear cholesteatoma is one of the common ear diseases. In the middle ear cholesteatoma, keratinocytes over-proliferate and keratin debris accumulates. In this paper, we reviewed the recent studies on middle ear cholesteatoma and explained the possible mechanisms of keratin in the pathogenesis of middle ear cholesteatoma from the aspects of "proliferation" and " bone resorption ". At the same time, the existing problems as well as the prospect of the future research were discussed. 10.3760/cma.j.issn.1673-0860.2019.11.014
Proteasome inhibitors stimulate both bone formation and hair growth by similar mechanisms. Mundy Gregory,Gutierrez Gloria,Garrett Ross,Gallwitz Wolfgang,Rossini Gianni,Christiansen Claus,Langenberg Andria Annals of the New York Academy of Sciences We propose that the remodeling process that occurs in localized areas on endosteal bone surfaces and in Haversian canals shares many features in common with the mammalian hair cycle. In both, there are phases of resorption or regeneration, a transition phase, and then a phase of growth, termed anagen in the hair follicle, and formation in the bone remodeling cycle. Furthermore, we suggest that these processes both use the same molecular mechanisms, and specifically the Hedgehog-BMP-Wnt signal transduction cascades. We have found that proteasome inhibitors, which enhance bone formation by effects on these cascades, also stimulate anagen induction and hair growth in the murine and human hair follicle, and propose they do so by effects on similar or identical molecular targets. 10.1196/annals.1402.077
[Vitamin D]. Miyaura C,Suda T Nihon rinsho. Japanese journal of clinical medicine 1 alpha,25-Dihydroxyvitamin D3 [1 alpha,25(OH)2D3], the active form of vitamin D3, stimulates intestinal calcium absorption and osteoclastic bone resorption, resulting in the elevation of plasma calcium. Recent studies have revealed that 1 alpha,25(OH)2D3 also promotes differentiation of various cells such as myeloid leukemia cells, lymphocytes, macrophages and skin keratinocytes. The target cells of 1 alpha,25(OH)2D3 possess 1 alpha,25(OH)2D3 receptors (VDR) which belong to the steroid thyroid retinoic acid receptor gene family. The complex of VDR and 1 alpha,25(OH)2D3 binds to vitamin D3-responsive elements (VDRE) present in the promoter region of target genes of 1 alpha,25(OH)2D3. In bone, osteoblasts possess VDR and synthesize several proteins, such as BGP, osteopontin and the third component of complement (C3), in response to 1 alpha, 25(OH)2D3. 1 alpha, 25(OH)2D3 is involved in the differentiation of osteoclast progenitors into mature osteoclasts directly and also by an indirect mechanism involving some proteins produced by osteoblasts. In this review article, we show the mode of action and the biological function of 1 alpha, 25(OH)2D3.
Receptors for 1alpha,25(OH)2D3: past, present, and future. Norman A W Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research 10.1359/jbmr.1998.13.9.1360
Epidermal regulation of bone morphogenesis through the development and regeneration of osteoblasts in the zebrafish scale. Iwasaki Miki,Kuroda Junpei,Kawakami Koichi,Wada Hironori Developmental biology Bone is a connective tissue composed of many cell types, including osteoblasts. How bones acquire their unique size and shape during development remains poorly understood. Herein we investigated the molecular and cellular mechanisms of bone morphogenesis in the zebrafish scale by using transgenic lines to enable visualization of specific types of osteoblasts. We demonstrate that the zebrafish scale contains three distinct types of osteoblasts: (i) a monolayer of central osteoblasts along the inner surface of scales; (ii) marginal osteoblasts elongated along the scale edge; and (iii) submarginal osteoblasts located between the central and marginal osteoblast populations. The size of the central osteoblasts increases progressively during development, suggesting that scale growth is mediated primarily by cell growth rather than the recruitment of new osteoblasts. In addition, the total number of central osteoblasts increases in regenerated scales and is correlated with scale size, possibly allowing for the rapid growth of regenerating scales. Moreover, osteoblast proliferation is not detected during regeneration, suggesting that the osteoblasts originate from post-mitotic precursor cells. Sonic hedgehog a (shha) is expressed in the epidermal cells that make contact with the marginal osteoblasts. Pharmacological inhibition of Hedgehog (Hh) signaling during regeneration reduces the number of marginal osteoblasts and interferes with scale growth, indicating that epidermis-derived Shh regulates scale regeneration. Finally, genetic inhibition of Wnt/planar cell polarity (PCP) signaling in the epidermis results in misorientation of scales with regard to the body axis. These results reveal a novel role for the epidermis in the regulation of bone patterning, namely the regeneration of osteoblasts and directional bone growth. 10.1016/j.ydbio.2018.03.005
Inflammatory stimulation of osteoblasts and keratinocytes from a SAPHO patient for implant risk evaluation. Swiss dental journal The present report exemplifies a translational method, which could assist the clinical preevaluation of patients at risk before surgical interventions. In this study, a presurgical implant decision in a case of SAPHO (synovitis, acne, palmoplantar pustulosis, hyperostosis, osteitis) is described. Since the etiology of this syndrome is likely to involve genetic, infectious and immunological components, lipopolysaccharides (LPS) may conceptually trigger cytokine production leading to a specific chronic inflammation and immunological host response. This may hamper proper healing or accentuate the destruction of periodontal host tissues. In our approach, we examined the ex vivo cell viability and immune responses of primary osteoblasts and keratinocytes under sterile inflammation induced by P. gingivalis LPS. Keratinocytes and osteoblasts were obtained from biopsies of the keratinized gingiva and alveolar bone tissues of a SAPHO human subject. Enzymatically dissociated cells were thus cultured and incubated to LPS at different concentrations (50ng/ml, 200ng/ml, 500ng/ml and 1μg/ml) for 24 h in order to test inflammatory cytokine response (quantitative real time PCR) and toxicity (cell viability). Healthy primary keratinocytes and osteoblasts were used as control cells. The highest concentration of LPS (1μg/ml) significantly reduced cell viability (p < 0.05). Meanwhile, all tested LPS concentrations similarly enhanced the mRNA expressions of selected inflammatory cytokines (TNFα, IL-6, IL-8, IL-1β and IL-1𝛼) up to ≈3.5-fold, when compared to the healthy cell controls (p < 0.05). This study demonstrated a valuable inflammatory risk evaluation before implant placement, which was successfully performed based on the presented laboratory diagnostic/prognostic approach.Sapho. 10.61872/sdj-2023-05-01
Higher degree of keratinization correlated with severe bone destruction in acquired Cholesteatoma. Acta oto-laryngologica BACKGROUND:Acquired cholesteatoma is characterized by hyper-keratinized squamous epithelium and bone destruction. However, direct evidence for hyper-keratinized epidermis promoting bone destruction is lacking. AIMS/OBJECTIVES:To determine whether higher degree of keratinization correlated with severe bone destruction and further offer direct evidence for keratinocyte-inducing osteoclastogenesis. MATERIALS AND METHODS:Histological changes and clinical relevance were analyzed in human-acquired cholesteatoma. Animal models were established by implanting autologous epidermis with different degrees of keratinization. The severity of bone resorption and the number of osteoclasts were compared in different keratinized groups. An coculture system was developed to mimic the progress of keratinocyte-inducing osteoclastogenesis. RESULTS:The matrix of cholesteatoma was composed of a thicker stratum corneum than normal skin. The stratum corneum thickness and the expression of Keratin 10 positively correlated to the severity of bone destruction. Animal models revealed that the bone destruction induced by a higher keratinized epidermis was more severe. Osteoclasts were detected in bone erosion areas, and the number of osteoclasts increased with the keratinization degrees of the graft. studies showed that keratinocytes directly promoted monocytes differentiating into osteoclasts. CONCLUSIONS AND SIGNIFICANCE:In acquired cholesteatoma, the degree of keratinization correlated with disease severity, and keratinocytes directly promote osteoclastogenesis. 10.1080/00016489.2023.2177341
Reversal of alopecia areata, osteoporosis follow treatment with activation of Tgr5 in mice. Bioscience reports BACKGROUND:Alopecia areata is an autoimmune hair loss disease with infiltration of pro-inflammatory cells into hair follicles. The role of Tgr5 in dermatitis has attracted considerable attention. The present study aimed to investigate the effect of Tgr5 in the development of Alopecia areata. METHODS:The study utilized a comparison control group design with four groups of wild-type group, wild-type+INT777 group, Tgr5-/- group, and Tgr5-/-+INT777 group. The mice were treated with INT777 (30 mg/kg/day) or the carrier solution (DMSO) intraperitoneally for 7 weeks, and the back skin was collected and analyzed by histology and immunohistochemistry staining. The lumbar vertebrae 4 has also been analyzed by DXA and Micro-CT. RESULTS:Tgr5-/- mice displayed the decreasingly significant in hair area and length, skin thickness, and the ratio of anagen and telogen, collagen, and mast cell number and loss the bone mass than WT group. After treating with INT777, the appearance of alopecia areata and bone microstructure has improved. Immunohistochemistry and qPCR analysis showed that activation of Tgr5 can down-regulate the express of JAK1, STAT3, IL-6, TNF-α, and VEGF. CONCLUSION:These findings indicate that activation of Tgr5 mediated amelioration of alopecia areata and osteoporosis by down-regulated JAK1-STAT3 signaling pathway. 10.1042/BSR20210609
GHRH expression plasmid improves osteoporosis and skin damage in aged mice. Ye Rui,Wang Hai-Long,Zeng De-Wei,Chen Ting,Sun Jia-Jie,Xi Qian-Yun,Zhang Yong-Liang Growth hormone & IGF research : official journal of the Growth Hormone Research Society and the International IGF Research Society The hormone secretion of GHRH-GH-IGF-1 axis in animals was decreased as aging. These hormones play an important role in maintaining bone mass and bone structure, and also affect the normal structure and function of the skin. We used plasmid-based technology to deliver growth hormone releasing hormone (GHRH) to elderly mice. In the current study, 80 and 120 μg/kg pVAX-GHRH plasmid expression plasmid were injected into old mice, the serum GHRH and insulin-like growth factor-1(IGF-1) content were increased within three weeks (P < 0.05). In the groups of 80 and 120 μg/kg plasmid, the content of procollagen type I N-terminal pro-peptide (PINP) in the serum was increased(P < 0.05), and the content of C-terminal telopeptides of type I collagen (CTX-1) in the serum was reduced significantly (P < 0.05). Furthermore, the expression of osteoprotegerin (OPG) and osteocalcin (OCN) in the femur also was increased(P < 0.05). The bone mineral density(BMD)、trabecular bone volume (BV/TV) and trabecular number(Tb.N) of mouse femur were increased significantly (P < 0.05) and trabecular separation(Tb.Sp) was decreased(P < 0.05). There were more trabecular bones in the bone marrow cavity and the trabecular bones are thicker in the groups of 80 and 120 μg/kg plasmid relative to control. The superoxide dismutase (SOD) content in the skin was increased(P < 0.05), and the malondialdehyde (MDA) content was reduced significantly (P < 0.05). Meanwhile, the skin moisture content also increased significantly(P < 0.05). Moreover, the expression of matrix metalloproteinase 3(MMP3) and matrix metalloproteinase 9(MMP9) was decreased in the skin(P < 0.05). The thickness of the dermis and epidermis of the skin had increased significantly(P < 0.05). Skin structure is more dense and complete in the two groups. These results indicate that 80 and 120 μg/kg plasmid-mediated GHRH supplementation can improve osteoporosis and skin aging in aged mice. 10.1016/j.ghir.2021.101429
Histatin-1 is a novel osteogenic factor that promotes bone cell adhesion, migration, and differentiation. Torres Pedro,Hernández Nadia,Mateluna Carlos,Silva Patricio,Reyes Montserrat,Solano Luis,Venegas Sebastián,Criollo Alfredo,Nazmi Kamran,Bikker Floris J,Bolscher Jan G M,Garrido Mauricio,Cáceres Mónica,Torres Vicente A Journal of tissue engineering and regenerative medicine Histatin-1 is a salivary antimicrobial peptide involved in the maintenance of enamel and oral mucosal homeostasis. Moreover, Histatin-1 has been shown to promote re-epithelialization in soft tissues, by stimulating cell adhesion and migration in oral and dermal keratinocytes, gingival and skin fibroblasts, endothelial cells and corneal epithelial cells. The broad-spectrum activity of Histatin-1 suggests that it behaves as a universal wound healing promoter, although this is far from being clear yet. Here, we report that Histatin-1 is a novel osteogenic factor that promotes bone cell adhesion, migration, and differentiation. Specifically, Histatin-1 promoted cell adhesion, spreading, and migration of SAOS-2 cells and MC3T3-E1 preosteoblasts in vitro, when placed on a fibronectin matrix. Besides, Histatin-1 induced the expression of osteogenic genes, including osteocalcin, osteopontin, and Runx2, and increased both activity and protein levels of alkaline phosphatase. Furthermore, Histatin-1 promoted mineralization in vitro, as it augmented the formation of calcium deposits in both SAOS-2 and MC3T3-E1 cells. Mechanistically, although Histatin-1 failed to activate ERK1/2, FAK, and Akt, which are signaling proteins associated with osteogenic differentiation or cell migration, it triggered nuclear relocalization of β-catenin. Strikingly, the effects of Histatin-1 were recapitulated in cells that are nonosteogenically committed, since it promoted surface adhesion, migration, and the acquisition of osteogenic markers in primary mesenchymal cells derived from the apical papilla and dental pulp. Collectively, these observations indicate that Histatin-1 is a novel osteogenic factor that promotes bone cell differentiation, surface adhesion and migration, as crucial events required for bone tissue regeneration. 10.1002/term.3177
In vitro-induced differentiation of bone marrow mesenchymal stem cells into melanocytes. Mei Xingyu,Sun Yue,Wu Zhouwei,Pan Weihua,Zhu Jianyu,Shi Weimin Cell biology international Large numbers of autogenous melanocytes (Mcs) are required when conducting studies on tissue engineering of skin and performing surgical treatment of depigmentation diseases. This study was conducted to explore the possibility of inducing differentiation of bone marrow mesenchymal stem cells (MSCs) into Mcs as a means of providing autogenous Mcs for purposes of tissue engineering and clinical treatment. MSCs were harvested from the bone marrows of black mice; and after six passages, hydrocortisone, insulin, transferrin and fibroblast growth factor were applied to induce their differentiation into Mcs. The morphological and ultrastructural characteristics of the newly differentiated cells were observed. The transcription and expression of multiple markers were examined using qRT-PCR, Western blot, and immunofluorescence analysis. Cell cycle phases and yields of Mcs were analyzed by flow cytometry. Following 120-180 days induction, differentiated cells were morphologically similar to Mcs, and mature melanosomes were observed. Multiple markers of Mcs, but not melanoma cells, were expressed by the differentiated cells. Most induced Mcs were in phase G1 or S, and yield of target cells was ∼80%. Mcs induced from bone marrow MSCs for periods of 120-180 days represent a potential source of autogenous Mcs. 10.1002/cbin.10455
Cysteine proteases as disease markers. Berdowska Izabela Clinica chimica acta; international journal of clinical chemistry This review comprises issues concerning cysteine cathepsins (CCs): human peptidases belonging to papain family (C1) of clan CA of cysteine proteases: cathepsins B, L, H, S, K, F, V, X, W, O and C. The involvement of these enzymes in physiological and pathological processes is described, especially with respect to their application as diagnostic and prognostic markers. They participate in precursor protein activation (including proenzymes and prohormones), MHC-II-mediated antigen presentation, bone remodeling, keratinocytes differentiation, hair follicle cycle, reproduction and apoptosis. Cysteine cathepsins upregulation has been demonstrated in many human tumors, including breast, lung, brain, gastrointestinal, head and neck cancer, and melanoma. Besides cancer diseases, they have been implied to participate in inflammatory diseases, such as inflammatory myopathies, rheumatoid arthritis, and periodontitis. Also, certain hereditary disorders are connected with mutations in CCs genes, what is observed in pycnodysostosis resulted from catK gene mutation and Papillon-Lefevre and Haim-Munk syndrome caused by catC gene defect. The potential application of cysteine cathepsins in diagnosis and/or prognosis is discussed in cancer diseases (breast, lung, head and neck, ovarian, gastrointestinal cancers, melanoma), as well as other disorders (periodontitis, rheumatoid arthritis, osteoarthritis). 10.1016/j.cccn.2003.12.016
A view on the skin-bone axis: unraveling similarities and potential of crosstalk. Frontiers in medicine The phrase "skin as a mirror of internal medicine," which means that the skin reflects many of the diseases of the internal organs, is a well-known notion. Despite the phenotypic differences between the soft skin and hard bone, the skin and bone are highly associated. Skin and bone consist of fibroblasts and osteoblasts, respectively, which secrete collagen and are involved in synthesis, while Langerhans cells and osteoclasts control turnover. Moreover, the quality and quantity of collagen in the skin and bone may be modified by aging, inflammation, estrogen, diabetes, and glucocorticoids. Skin and bone collagen are pathologically modified by aging, drugs, and metabolic diseases, such as diabetes. The structural similarities between the skin and bone and the crosstalk controlling their mutual pathological effects have led to the advocacy of the skin-bone axis. Thus, the skin may mirror the health of the bones and conversely, the condition of the skin may be reflected in the bones. From the perspective of the skin-bone axis, the similarities between skin and bone anatomy, function, and pathology, as well as the crosstalk between the two, are discussed in this review. A thorough elucidation of the pathways governing the skin-bone axis crosstalk would enhance our understanding of disease pathophysiology, facilitating the development of new diagnostics and therapies for skin collagen-induced bone disease and of new osteoporosis diagnostics and therapies that enhance skin collagen to increase bone quality and density. 10.3389/fmed.2024.1360483
Cytokines that promote periodontal tissue destruction. Graves Dana Journal of periodontology Although periodontal diseases are initiated by bacteria that colonize the tooth surface and gingival sulcus, the host response is believed to play an essential role in the breakdown of connective tissue and bone, key features of the disease process. An intermediate mechanism that lies between bacterial stimulation and tissue destruction is the production of cytokines, which stimulates inflammatory events that activate effector mechanisms. These cytokines can be organized as chemokines, innate immune cytokines, and acquired immune cytokines. Although they were historically identified as leukocyte products, many are also produced by a number of cell types, including keratinocytes, resident mesenchymal cells (such as fibroblasts and osteoblasts) or their precursors, dendritic cells, and endothelial cells. Chemokines are chemotactic cytokines that play an important role in leukocyte recruitment and may directly or indirectly modulate osteoclast formation. This article focuses on aspects of osteoimmunology that affect periodontal diseases by examining the role of cytokines, chemokines, and immune cell mediators. It summarizes some of the key findings that attempt to delineate the mechanisms by which immune factors can lead to the loss of connective tissue attachment and alveolar bone. In addition, a discussion is presented on the importance of clarifying the process of uncoupling, a process whereby insufficient bone formation occurs following resorption, which is likely to contribute to net bone loss in periodontal disease. 10.1902/jop.2008.080183
Regulation and function of the E-cadherin/catenin complex in cells of the monocyte-macrophage lineage and DCs. Van den Bossche Jan,Malissen Bernard,Mantovani Alberto,De Baetselier Patrick,Van Ginderachter Jo A Blood E-cadherin is best characterized as adherens junction protein, which through homotypic interactions contributes to the maintenance of the epithelial barrier function. In epithelial cells, the cytoplasmic tail of E-cadherin forms a dynamic complex with catenins and regulates several intracellular signal transduction pathways, including Wnt/β-catenin, PI3K/Akt, Rho GTPase, and NF-κB signaling. Recent progress uncovered a novel and critical role for this adhesion molecule in mononuclear phagocyte functions. E-cadherin regulates the maturation and migration of Langerhans cells, and its ligation prevents the induction of a tolerogenic state in bone marrow-derived dendritic cells (DCs). In this respect, the functionality of β-catenin could be instrumental in determining the balance between immunogenicity and tolerogenicity of DCs in vitro and in vivo. Fusion of alternatively activated macrophages and osteoclasts is also E-cadherin-dependent. In addition, the E-cadherin ligands CD103 and KLRG1 are expressed on DC-, T-, and NK-cell subsets and contribute to their interaction with E-cadherin-expressing DCs and macrophages. Here we discuss the regulation, function, and implications of E-cadherin expression in these central orchestrators of the immune system. 10.1182/blood-2011-10-384289
Fleas and lesions in armadillo osteoderms. Journal of anatomy Armadillos are bitten by several species of flea. Females of the genus Tunga penetrate the epidermis and when in place are fertilised by males, after which the abdomen swells enormously to form a 'neosome'. Within the penetrans group, T. perforans, makes lesions that perforate the osteoderms within the integument to form ~3 mm diameter cavities occupied by a discoid neosome. We examined these lesions in carapace material from animals which had died in the wild to see whether we could recruit evidence as to how they may be generated, either by the insect or by the host. We studied one species without such lesions, the nine-banded armadillo Dasypus novemcinctus, and two species with, the greater hairy armadillo Chaetophractus villosus and the southern three-banded armadillo Tolypeutes matacus, both showing the characteristic 'flea bite' holes in the external surfaces of the osteoderms. Samples were studied by three-dimensional backscattered electron mode scanning electron microscopy and X-ray microtomography. Both methods showed resorption pit complexes in the external surfaces of the osteoderms characteristic of those made by osteoclasts in active bone resorption. Lesions involved both the syndesmoses (sutures) between adjacent bones and the central regions of the osteoderms. Many lesions showed extensive repair by infilling with new bone. We conclude that the T. perforans neosome creates a local host response which causes bone resorption, creating the space in which it can grow. 10.1111/joa.13842
Ectopic expression of the osteogenic master gene in melanoma. Valenti Maria Teresa,Dalle Carbonare Luca,Mottes Monica World journal of stem cells The transcription factor is the osteogenic master gene expressed in mesenchymal stem cells during osteogenic commitment as well as in pre-osteoblasts and early osteoblasts. However, is also ectopically expressed in melanoma and other cancers. Malignant melanoma (MM) is a highly metastatic skin cancer. The incidence of MM has increased considerably in the past half-century. The expression levels and mutation rates of genes such as , , , , , and are higher in melanoma than in other solid malignancies. Additionally, transcription factors can affect cellular processes and induce cellular transformation since they control gene expression. Recently, several studies have identified alterations in expression. In particular, the regulation of by and the increased expression of in melanoma specimens have been shown. Melanocytes, whose transformation results in melanoma, arise from the neural crest and therefore show "stemness" features. plays an important role in the re-activation of the MAPK and PI3K/AKT pathways, thus endowing melanoma cells with a high metastatic potential. In melanoma, the most frequent metastatic sites are the lung, liver, brain and lymph nodes. In addition, bone metastatic melanoma has been described. Notably, studies focusing on may contribute to the identification of an appropriate oncotarget in melanoma. 10.4252/wjsc.v10.i7.78
The pathological role of Wnt5a in psoriasis and psoriatic arthritis. Tian Faming,Mauro Theodora M,Li Zhengxiao Journal of cellular and molecular medicine Psoriasis (PsO) is a chronic inflammatory skin disease with both local and systemic components. PsO-associated arthritis, known as psoriatic arthritis (PsA), develops in approximately 13%-25% of PsO patients. Various factors associated with both PsO and PsA indicate that these conditions are part of a single disease. Identification of novel targets for the development of drugs to treat both PsO and PsA is desirable to provide more patient-friendly treatment regimens. Such targets will likely represent 'common checkpoints' of inflammation, for example key components or transduction cascades of the signalling pathways involved. Emerging evidence supports involvement of the non-canonical Wnt signalling pathways in the development of both PsO and PsA, especially the Wnt5a-activated signalling cascades. These, together with interlinked factors, are crucial in the interactions among keratinocytes, immune cells and inflammatory factors in PsO, as well as among chondrocytes, osteoblasts and osteoclasts that trigger both subchondral bone remodelling and cartilage catabolism in PsA. This review focuses on the pathological role of Wnt5a signalling and its interaction with other interlinked pathways in both PsO and PsA, and also on the main challenges for future research, particularly with respect to molecules targeting Wnt signalling pathways for the treatment of PsO and PsA. 10.1111/jcmm.14531
Hair follicle stem cells differentiation into bone cells on collagen scaffold. Cell and tissue banking The hair follicle is a dynamic structure which contains different niches for stem cells, therefore; it has been considered as valuable and rich sources of stem cells, due to easy access, multipotency and non-oncogenic properties. In the present study, the differentiation capacities of hair follicle stem cells into bone cells on the natural collagen scaffolds were investigated. The stem cells were extracted from the hair follicle bulge area of male Wistar rats' whisker and cultured until 3rd passage, then osteogenic differentiations were induced by culturing the cells in the specific osteogenic medium. After 3 weeks, the differentiation parameters, including morphological changes, levels of calcification and expression of the bone specific genes were detected. The hydrogel preparation and scaffold fabrication was carried out using the extracted collagen and was studied by scanning electron microscope. Comparison of the stem cells' growth and changes on the scaffold and non-scaffold conditions showed that, in the both situation, the cells revealed differentiation signs of osteocytes, including large and cubic morphology with a star-shaped nucleus. Staining by Alizarin-red and Von-Kossa methods showed the presence of red and black calcium mass on the scaffold. Expression of the osteopontin and alkaline phosphatase genes confirmed the differentiation. Considerable porosity in the surface of the scaffold was recorded by scanning electron microscopy, which made it convenient for cells' attachment and growth. The data showed that the bulge stem cells possess significant capacity for osteoblastic differentiation and collagen scaffolds were found to be an appropriate matrix for growth and differentiation of the cell. 10.1007/s10561-020-09812-9
Exosomal miR-4645-5p from hypoxic bone marrow mesenchymal stem cells facilitates diabetic wound healing by restoring keratinocyte autophagy. Burns & trauma Background:Refractory diabetic wounds are a common occurrence in patients with diabetes and epidermis-specific macroautophagy/autophagy impairment has been implicated in their pathogenesis. Therefore, identifying and developing treatment strategies capable of normalizing epidermis-specific macroautophagy/autophagy could facilitate diabetic wound healing. The study aims to investigate the potential of bone marrow mesenchymal stem cell-derived exosomes (BMSC-exos) from hypoxic conditions as a treatment to normalize epidermis-specific autophagy for diabetic wound healing. Methods:We compared the effects of bone marrow mesenchymal stem cell (BMSC)-sourced exosomes (BMSC-Exos) from hypoxic conditions to those of BMSC in normoxic conditions (noBMSC-Exos). Our studies involved morphometric assessment of the exosomes, identification of the microRNA (miRNA) responsible for the effects, evaluation of keratinocyte functions and examination of effects of the exosomes on several molecules involved in the autophagy pathway such as microtubule-associated protein 1 light chain 3 beta, beclin 1, sequestosome 1, autophagy-related 5 and autophagy-related 5. The experiments used human BMSCs from the American Type Culture Collection, an mouse model of diabetes (db/db) to assess wound healing, as well as the human keratinocyte HaCaT cell line. In the methodology, the authors utilized an array of approaches that included electron microscopy, small interfering RNA (siRNA) studies, RNA hybridization, quantitative real-time reverse transcription PCR (qRT-PCR), the isolation, sequencing and differential expression of miRNAs, as well as the use of miR-4645-5p-specific knockdown with an inhibitor. Results:Hypoxia affected the release of exosomes from hypoxic BMSCs (hy-BMSCs) and influenced the size and morphology of the exosomes. Moreover, hyBMSC-Exo treatment markedly improved keratinocyte function, including keratinocyte autophagy, proliferation and migration. miRNA microarray and bioinformatics analysis showed that the target genes of the differentially expressed miRNAs were mainly enriched in 'autophagy' and 'process utilizing autophagic mechanism' in the 'biological process' category and miR-4645-5p as a major contributor to the pro-autophagy effect of hyBMSC-Exos. Moreover, mitogen-activated protein kinase-activated protein kinase 2 (MAPKAPK2) was identified as a potential target of exosomal miR-4645-5p; this was confirmed using a dual luciferase assay. Exosomal miR-4645-5p mediates the inactivation of the MAPKAPK2-induced AKT kinase group (comprising AKT1, AKT2, and AKT3), which in turn suppresses AKT-mTORC1 signaling, thereby facilitating miR-4645-5p-mediated autophagy. Conclusions:Overall, the results of this study showed that hyBMSC-Exo-mediated transfer of miR-4645-5p inactivated MAPKAPK2-induced AKT-mTORC1 signaling in keratinocytes, which activated keratinocyte autophagy, proliferation and migration, resulting in diabetic wound healing in mice. Collectively, the findings could aid in the development of a novel therapeutic strategy for diabetic wounds. 10.1093/burnst/tkad058
The function of dendritic cells in modulating the host response. Song L,Dong G,Guo L,Graves D T Molecular oral microbiology Dendritic cells (DCs) are antigen-presenting cells that capture, process, and present antigens to lymphocytes to initiate and regulate the adaptive immune response. DCs detect bacteria in skin and mucosa and migrate into regional lymph nodes, where they stimulate antigen-specific T and B lymphocyte activation and proliferation. DCs direct CD4 T cells to differentiate to T-cell subsets such as T helper cells types 1, 2, and 17, and regulatory T cells. The periodontium is chronically exposed to oral bacteria that stimulate an inflammatory response to induce gingivitis or periodontitis. DCs play both protective and destructive roles through activation of the acquired immune response and are also reported to be a source of osteoclast precursors that promote bone resorption. FOXO1, a member of the forkhead box O family of transcription factors, plays a significant role in the activation of DCs. The function of DCs in periodontal inflammation has been investigated in a mouse model by lineage-specific deletion of FOXO1 in these cells. Deletion of FOXO1 reduces DC protective function and enhances susceptibility to periodontitis. The kinase Akt, phosphorylates FOXO1 to inhibit FOXO activity. Hence the Akt-FOXO1 axis may play a key role in regulating DCs to have a significant impact on periodontal disease. 10.1111/omi.12195
Mesenchymal stem cells: The roles and functions in cutaneous wound healing and tumor growth. Motegi Sei-Ichiro,Ishikawa Osamu Journal of dermatological science Mesenchymal stem cells (MSCs) are bone marrow-derived non-hematopoietic progenitor cells. MSCs are able to differentiate into various types of cells, including chondrocytes, adipocytes, osteocytes, myocytes, endothelial cells, and keratinocytes. There is increasing evidence that MSCs might be located external to the vasculature, and that perivascular cells in the skin, generally called as "pericytes", might include MSCs. It has been suggested that MSCs localized around blood vessels might migrate into wounds and contribute to the restoration of injured tissues. Many studies have demonstrated that intravenous or intradermal administration of MSCs enhanced cutaneous wound healing, such as acute incisional and excisional wounds, diabetic ulcers, radiation ulcers, and burns in animals and humans. Several mechanisms of the acceleration of wound healing by MSCs have been identified, including the enhancement of angiogenesis by secretion of pro-angiogenic factors and the differentiation into endothelial cells and/or pericytes, M2 macrophages polarization, the recruitment of endogenous stem/progenitor cells, extracellular matrix production and remodeling, and immunosuppressive effects. Since the microenvironments of wounds and/or injured tissues are similar to those of tumors, MSCs also play similar roles in malignant tumors, such as the enhancement of angiogenesis, M2 macrophages polarization, and immunosuppressive effects. In addition, the mechanisms of homing of MSCs might have a commonality in the pathogenesis of wound healing and tumors. Thus, the regulating factors of MSCs, including MFG-E8, could be a therapeutic target and lead to the establishment of new therapeutic approaches for both intractable wound healing and tumors. 10.1016/j.jdermsci.2016.11.005
The IL-23/IL-17 axis in psoriatic arthritis. Suzuki Erika,Mellins Elizabeth D,Gershwin M Eric,Nestle Frank O,Adamopoulos Iannis E Autoimmunity reviews Psoriatic arthritis (PsA) is an immune-mediated chronic inflammatory disease, affecting both the skin and joints. Disease progression is associated with aberrant cytokine expression, and TNF blockade is the most successful therapy to date. However, not all patients are responsive to anti-TNF treatment, highlighting the need to better understand the cellular and molecular mechanisms that govern the disease. PsA associations with single nucleotide polymorphisms in IL23R as well as TRAF3IP2 (Act1), a molecule downstream of the IL-17 receptor (IL-17R), have linked the IL-23/IL-17 axis to disease pathology. Although both cytokines are implicated in PsA, a full picture of their cellular targets and pathogenic mechanisms has not yet emerged. In this review, we focus on the IL-23/IL-17 axis-elicited responses mediated by osteoclasts, keratinocytes and neutrophils. Expanding our understanding of the cellular and molecular mechanisms that dictate pathogenicity in PsA will contribute to developing novel treatment strategies to combat disease. 10.1016/j.autrev.2014.01.050
Recent advances in the regulation mechanism of . Journal of otology Neural crest (NC) is the primitive neural structure in embryonic stage, which develops from ectodermal neural plate cells and epithelial cells. When the neural fold forms into neural tube, neural crest also forms a cord like structure above the neural tube and below the ectoderm. Neural crest cells (NCC) have strong migration and proliferation abilities. A number of tissue cells differentiate from neural crest cells, such as melanocytes, central and peripheral neurons, glial cells, craniofacial cells, osteoblasts, chondrocytes and smooth muscle cells. The migration and differentiation of neural crest cells are regulated by a gene network where a variety of genes, transcriptional factors, signal pathways and growth factors are involved. 10.1016/j.joto.2022.08.003
Of skin and bone: did Langerhans cells and osteoclasts evolve from a common ancestor? Mueller Christopher G,Voisin Benjamin Journal of anatomy Skin Langerhans cells are antigen-presenting cells of the interfollicular epidermis and the upper part of the hair follicle, whereas osteoclasts are specialized bone-resorbing macrophages. Although at first view these two cell types appear to have little in common, a closer analysis reveals shared features, and when taking into account their surrounding environment, a hypothesis can be developed that Langerhans cells and osteoclasts have evolved from a common ancestral cell type. In this mini-review, we have compared the ontogenetic features of Langerhans cells and osteoclasts from a genetic and a functional point of view, an issue that so far has been overlooked. The gene programs that control cell differentiation, and the body parts where they reside, present surprising similarities. Whereas the function of osteoclasts in bone degradation has been established since the first vertebrates, Langerhans cells may have undergone a stepwise adaptation from aquatic to terrestrial life. Their cell function co-evolved with the imperatives of the skin to protect against physical impact, heat, water loss and pathogens, which implied the capacity of Langerhans cells to associate with skin appendages and to develop immunostimulatory functions. For the highly versatile and efficient immune system of modern vertebrates, Langerhans cells may be a memory of the past. 10.1111/joa.12543
The M-CSF receptor in osteoclasts and beyond. Experimental & molecular medicine Colony-stimulating factor 1 receptor (CSF1R, also known as c-FMS) is a receptor tyrosine kinase. Macrophage colony-stimulating factor (M-CSF) and IL-34 are ligands of CSF1R. CSF1R-mediated signaling is crucial for the survival, function, proliferation, and differentiation of myeloid lineage cells, including osteoclasts, monocytes/macrophages, microglia, Langerhans cells in the skin, and Paneth cells in the intestine. CSF1R also plays an important role in oocytes and trophoblastic cells in the female reproductive tract and in the maintenance and maturation of neural progenitor cells. Given that CSF1R is expressed in a wide range of myeloid cells, altered CSF1R signaling is implicated in inflammatory, neoplastic, and neurodegenerative diseases. Inhibiting CSF1R signaling through an inhibitory anti-CSF1R antibody or small molecule inhibitors that target the kinase activity of CSF1R has thus been a promising therapeutic strategy for those diseases. In this review, we cover the recent progress in our understanding of the various roles of CSF1R in osteoclasts and other myeloid cells, highlighting the therapeutic applications of CSF1R inhibitors in disease conditions. 10.1038/s12276-020-0484-z
[Recent advances in nephronectin]. Qian Guo-Qing,Yang Nai-Bin,Shi Jie-Jun Sheng li xue bao : [Acta physiologica Sinica] Nephronectin (NPNT) is a novel extracellular matrix protein and a new ligand of integrin α8β1. Recent studies showed that NPNT is highly expressed in kidney, lung, thyroid, etc, and it may play an important role in many pathological conditions. NPNT is involved in the process of kidney development and acute kidney injury, regulates proliferation and differentiation of osteoblast, and induces the vasculogenesis in vitro. NPNT may play a key role in pathological osteoporosis and therefore be a new therapeutic target of bone diseases. NPNT gene variants are not only associated with lung function, but also potentially implicated in chronic airway diseases development. Moreover, NPNT is also an important factor that mediates pathology of cardiac, epidermis, breast, liver and teeth diseases. In this paper, we reviewed some research progresses on the structure, distribution, physiological and pathophysiological functions of NPNT.
Hippo-Yap Pathway Orchestrates Neural Crest Ontogenesis. Frontiers in cell and developmental biology Neural crest (NC) cells are a migratory stem cell population in vertebrate embryogenesis that can give rise to multiple cell types, including osteoblasts, chondrocytes, smooth muscle cells, neurons, glia, and melanocytes, greatly contributing to the development of different tissues and organs. Defects in NC development are implicated in many human diseases, such as numerous syndromes, craniofacial aberration and congenital heart defects. Research on NC development has gained intense interest and made significant progress. Recent studies showed that the Hippo-Yap pathway, a conserved fundamental pathway with key roles in regulation of cell proliferation, survival, and differentiation, is indispensable for normal NC development. However, the roles and mechanisms of the Hippo-Yap pathway in NC development remain largely unknown. In this review, we summarize the key functions of the Hippo-Yap pathway indicated in NC induction, migration, proliferation, survival, and differentiation, as well as the diseases caused by its dysfunction in NC cells. We also discuss emerging current and future studies in the investigation of the Hippo-Yap pathway in NC development. 10.3389/fcell.2021.706623
[Drug-induced hypercalcemia]. Sato Kanji Clinical calcium Drug-induced hypercalcemia is caused by increased bone resorption (vitamin D and vitamin A intoxication), increased calcium absorption in the gastrointestinal tract (vitamin D intoxication, excessive intake of calcium) or increased calcium reabsorption in the renal tubules (thiazide diuretics). When vitamin D (D(2) or D(3)) intoxication develops, the hypercalcemia persists for more than several months. Therefore, short-acting active vitamin D (1alpha-OHD(3), 1,25- (OH) (2)D(3)) are clinically used. Recently, various analogs of 1,25- (OH) (2)D(3) with potent differentiation stimulating activity on keratinocytes but insufficient calcium-movilizing activity have been developed (tacalcitol, calcipotriol, 22-oxacalcitriol). However, severe hypercalcemia may develop when these ointments were abundantly applied to patients with psoriasis since the agents can be easily absorbed through the skin lesions. CliCa06016772
Molecular biology of cholesteatoma. Maniu Alma,Harabagiu Oana,Perde Schrepler Maria,Cătană Andreea,Fănuţă Bogdan,Mogoantă Carmen Aurelia Romanian journal of morphology and embryology = Revue roumaine de morphologie et embryologie Cholesteatoma is a non-neoplastic, keratinizing lesion, characterized by the proliferation of epithelium with aberrant micro-architecture into the middle ear and mastoid cavity. The exact pathogenic molecular mechanisms behind the formation and propagation of cholesteatoma remain unclear. Immunohistochemical examinations of the matrix and perimatrix have considerably improved the knowledge of cholesteatoma pathogenesis. In this review, the current concepts of cholesteatoma pathogenesis are discussed. Currently, the most widely acknowledged pathogenesis of acquired cholesteatoma is the theory that negative pressure, dysfunction of the Eustachian tube, causes a deepening retraction pocket that, when obstructed, desquamated keratin cannot be cleared from the recess, and a cholesteatoma results. Local infection leads to a disturbance of self-cleaning mechanisms, with cell debris and keratinocytes accumulate inside the retraction pocket, and this is followed by an immigration of immune cells, i.e., Langerhans' cells, T-cells, macrophages. There is an imbalance and a vicious circle of epithelial proliferation, keratinocyte differentiation and maturation, prolonged apoptosis, and disturbance of self-cleaning mechanisms. The inflammatory stimulus will induce an epithelial proliferation along with expression of lytic enzymes and cytokines. Bacteria inside the retraction pocket produce some antigens, which will activate different cytokines and lytic enzymes. These cytokines lead to activation and maturing of osteoclasts with the consequence of degradation of extracellular bone matrix and hyperproliferation, bone erosion and finally progression of the disease. Further research is necessary for a better understanding of the pathogenetic mechanisms and to expand the spectrum of therapeutic options.
The Immunologic Role of IL-17 in Psoriasis and Psoriatic Arthritis Pathogenesis. Clinical reviews in allergy & immunology Psoriasis is a chronic, immune-mediated, inflammatory disease that is pathogenically driven by proinflammatory cytokines. This article reviews the immunologic role of interleukin (IL)-17, the major effector cytokine in the pathogenesis of psoriatic disease, along with the rationale for targeting the IL-17 cytokine family (IL-17A, IL-17F, and IL-17 receptor A) in the treatment of psoriasis and psoriatic arthritis. Emerging evidence indicates that major sources of IL-17A in patients with psoriatic disease are mast cells, γδ T cells, αβ T cells, and innate lymphoid cells in lesional skin and synovial fluid. Within the skin and joints, IL-17A acts on cellular targets, including keratinocytes, neutrophils, endothelial cells, fibroblasts, osteoclasts, chondrocytes, and osteoblasts, to stimulate production of various antimicrobial peptides, chemokines, and proinflammatory and proliferative cytokines, which, in turn, promote tissue inflammation and bone remodeling. The critical importance of the IL-23/IL-17A axis to the pathogenesis of psoriatic disease has resulted in many new biologic treatments targeting these cytokines. These biologics dramatically improve skin and joint symptoms in patients with moderate-to-severe psoriasis and psoriatic arthritis. 10.1007/s12016-018-8702-3
CSF-1 receptor signaling in myeloid cells. Stanley E Richard,Chitu Violeta Cold Spring Harbor perspectives in biology The CSF-1 receptor (CSF-1R) is activated by the homodimeric growth factors colony-stimulating factor-1 (CSF-1) and interleukin-34 (IL-34). It plays important roles in development and in innate immunity by regulating the development of most tissue macrophages and osteoclasts, of Langerhans cells of the skin, of Paneth cells of the small intestine, and of brain microglia. It also regulates the differentiation of neural progenitor cells and controls functions of oocytes and trophoblastic cells in the female reproductive tract. Owing to this broad tissue expression pattern, it plays a central role in neoplastic, inflammatory, and neurological diseases. In this review we summarize the evolution, structure, and regulation of expression of the CSF-1R gene. We discuss the structures of CSF-1, IL-34, and the CSF-1R and the mechanism of ligand binding to and activation of the receptor. We further describe the pathways regulating macrophage survival, proliferation, differentiation, and chemotaxis downstream from the CSF-1R. 10.1101/cshperspect.a021857