Role of the Microbiome in Regulating Bone Metabolism and Susceptibility to Osteoporosis.
Calcified tissue international
The human microbiota functions at the interface between diet, medication-use, lifestyle, host immune development and health. It is therefore closely aligned with many of the recognised modifiable factors that influence bone mass accrual in the young, and bone maintenance and skeletal decline in older populations. While understanding of the relationship between micro-organisms and bone health is still in its infancy, two decades of broader microbiome research and discovery supports a role of the human gut microbiome in the regulation of bone metabolism and pathogenesis of osteoporosis as well as its prevention and treatment. Pre-clinical research has demonstrated biological interactions between the microbiome and bone metabolism. Furthermore, observational studies and randomized clinical trials have indicated that therapeutic manipulation of the microbiota by oral administration of probiotics may influence bone turnover and prevent bone loss in humans. In this paper, we summarize the content, discussion and conclusions of a workshop held by the Osteoporosis and Bone Research Academy of the Royal Osteoporosis Society in October, 2020. We provide a detailed review of the literature examining the relationship between the microbiota and bone health in animal models and in humans, as well as formulating the agenda for key research priorities required to advance this field. We also underscore the potential pitfalls in this research field that should be avoided and provide methodological recommendations to facilitate bridging the gap from promising concept to a potential cause and intervention target for osteoporosis.
10.1007/s00223-021-00924-2
The modulatory effect and implication of gut microbiota on osteoporosis: from the perspective of "brain-gut-bone" axis.
Zhang Yuan-Wei,Li Ying-Juan,Lu Pan-Pan,Dai Guang-Chun,Chen Xiang-Xu,Rui Yun-Feng
Food & function
Osteoporosis (OP) is a kind of systemic metabolic disease characterized by decreased bone mass and destruction of the bone microstructure. In recent years, it has become an expected research trend to explore the cross-linking relationship in the pathogenesis process of OP so as to develop reasonable and effective intervention strategies. With the further development of intestinal microbiology and the profound exploration of the gut microbiota (GM), it has been further revealed that the "brain-gut" axis may be a potential target for the bone, thereby affecting the occurrence and progression of OP. Hence, based on the concept of "brain-gut-bone" axis, we look forward to deeply discussing and summarizing the cross-linking relationship of OP in the next three parts, including the "brain-bone" connection, "gut-bone" connection, and "brain-gut" connection, so as to provide an emerging thought for the prevention strategies and mechanism researches of OP.
10.1039/d0fo03468a
The intestinal microbiota: from health to disease, and back.
Nathan Nayanan N,Philpott Dana J,Girardin Stephen E
Microbes and infection
Our understanding of the composition and the function of the intestinal microbiota has significantly increased over the past few years. In a series of reviews focusing on the role of the intestinal microbiota in health and disease, we explore recent conceptual and technological advances in this rapidly evolving research arena.
10.1016/j.micinf.2021.104849
Gut Microbiota and Diarrhea: An Updated Review.
Li Yunxia,Xia Siting,Jiang Xiaohan,Feng Can,Gong Saiming,Ma Jie,Fang Zhengfeng,Yin Jie,Yin Yulong
Frontiers in cellular and infection microbiology
Diarrhea is a common problem to the whole world and the occurrence of diarrhea is highly associated with gut microbiota, such as bacteria, fungi, and viruses. Generally, diarrheal patients or animals are characterized by gut microbiota dysbiosis and pathogen infections may lead to diarrheal phenotypes. Of relevance, reprograming gut microbiota communities by dietary probiotics or fecal bacteria transplantation are widely introduced to treat or prevent diarrhea. In this review, we discussed the influence of the gut microbiota in the infection of diarrhea pathogens, and updated the research of reshaping the gut microbiota to prevent or treat diarrhea for the past few years. Together, gut microbiota manipulation is of great significance to the prevention and treatment of diarrhea, and further insight into the function of the gut microbiota will help to discover more anti-diarrhea probiotics.
10.3389/fcimb.2021.625210
Obesity-Related Gut Microbiota Aggravates Alveolar Bone Destruction in Experimental Periodontitis through Elevation of Uric Acid.
Sato Keisuke,Yamazaki Kyoko,Kato Tamotsu,Nakanishi Yumiko,Tsuzuno Takahiro,Yokoji-Takeuchi Mai,Yamada-Hara Miki,Miura Nobuaki,Okuda Shujiro,Ohno Hiroshi,Yamazaki Kazuhisa
mBio
Obesity is a risk factor for periodontal disease (PD). Initiation and progression of PD are modulated by complex interactions between oral dysbiosis and host responses. Although obesity is associated with increased susceptibility to bacterial infection, the detailed mechanisms that connect obesity and susceptibility to PD remain elusive. Using fecal microbiota transplantation and a ligature-induced PD model, we demonstrated that gut dysbiosis-associated metabolites from high-fat diet (HFD)-fed mice worsen alveolar bone destruction. Fecal metabolomics revealed elevated purine degradation pathway activity in HFD-fed mice, and recipient mice had elevated levels of serum uric acid upon PD induction. Furthermore, PD induction caused more severe bone destruction in hyperuricemic than normouricemic mice, and the worsened bone destruction was completely abrogated by allopurinol, a xanthine oxidase inhibitor. Thus, obesity increases the risk of PD by increasing production of uric acid mediated by gut dysbiosis. Obesity is an epidemic health issue with a rapid increase worldwide. It increases the risk of various diseases, including periodontal disease, an oral chronic infectious disease. Although obesity increases susceptibility to bacterial infection, the precise biological mechanisms that link obesity and susceptibility to periodontal disease remain elusive. Using fecal microbial transplantation, experimental periodontitis, and metabolomics, our study demonstrates uric acid as a causative substance for greater aggravation of alveolar bone destruction in obesity-related periodontal disease. Gut microbiota from obese mice upregulated the purine degradation pathway, and the resulting elevation of serum uric acid promoted alveolar bone destruction. The effect of uric acid was confirmed by administration of allopurinol, an inhibitor of xanthine oxidase. Overall, our study provides new insights into the pathogenic mechanisms of obesity-associated periodontal disease and the development of new therapeutic options for the disease.
10.1128/mBio.00771-21
Gut microbiota and bone metabolism.
Lu Lingyun,Chen Xiaoxuan,Liu Yi,Yu Xijie
FASEB journal : official publication of the Federation of American Societies for Experimental Biology
Osteoporosis is the most common metabolic skeletal disease. It is characterized by the deterioration of the skeletal microarchitecture and bone loss, leading to ostealgia, and even bone fractures. Accumulating evidence has indicated that there is an inextricable relationship between the gut microbiota (GM) and bone homeostasis involving host-microbiota crosstalk. Any perturbation of the GM can play an initiating and reinforcing role in disrupting the bone remodeling balance during the development of osteoporosis. Although the GM is known to influence bone metabolism, the mechanisms associated with these effects remain unclear. Herein, we review the current knowledge of how the GM affects bone metabolism in health and disease, summarize the correlation between pathogen-associated molecular patterns of GM structural components and bone metabolism, and discuss the potential mechanisms underlying how GM metabolites regulate bone turnover. Deciphering the complicated relationship between the GM and bone health will provide new insights into the prevention and treatment of osteoporosis.
10.1096/fj.202100451R
The Association Between Gestational Diabetes and Microbiota in Placenta and Cord Blood.
Tang Ning,Luo Zhong-Cheng,Zhang Lin,Zheng Tao,Fan Pianpian,Tao Yexuan,Ouyang Fengxiu
Frontiers in endocrinology
Early life is a critical period for gut microbial development. It is still controversial whether there is placental microbiota during a healthy pregnancy. Gestational diabetes mellitus (GDM) is associated with increased risk of metabolic syndrome in the offspring, and the mechanisms are unclear. We sought to explore whether microbiota in placenta and cord blood may be altered in GDM. Placenta and cord blood samples were collected from eight GDM and seven euglycemic (control) term pregnancies in cesarean deliveries without evidence of clinical infections. The Illumina MiSeq Sequencing System was used to detect the microbiota based on the V3-V4 hypervariable regions of the 16S ribosomal RNA gene. The microbiota were detectable in all placental samples. Comparing GDM vs. controls, there were more operational taxonomic units (OTUs) (mean ± SE = 373.63 ± 14.61 vs. 332.43 ± 9.92, = 0.024) and higher ACE index (395.15 ± 10.56 vs. 356.27 ± 8.47, = 0.029) and Chao index (397.67 ± 10.24 vs. 361.32 ± 8.87, = 0.04). The placental microbiota was mainly composed of four phyla: , and at the phylum level and 10 dominant genera at the genus level in both GDM and controls. Despite the dominant similarity in microbiota composition, at the OTU level, the abundance of , and were higher, whereas was lower in the placentas of GDM vs. controls. The microbiota was detected in one of the 15 cord blood samples, and its components were similar as to the corresponding placental microbiota at both phylum and genus levels suggesting placental microbiota as the potential source. The most abundant phyla and genus of placental microbiota were similar in GDM and euglycemic pregnancies, but GDM was associated with higher diversity of placental microbiota. Further study is needed to confirm the existence of microbiota in cord blood in pregnancies without clinical infection.
10.3389/fendo.2020.550319
Role of dietary polyphenols on gut microbiota, their metabolites and health benefits.
Mithul Aravind S,Wichienchot Santad,Tsao Rong,Ramakrishnan S,Chakkaravarthi S
Food research international (Ottawa, Ont.)
The beneficial health roles of dietary polyphenols in preventing oxidative stress related chronic diseases have been subjected to intense investigation over the last two decades. As our understanding of the role of gut microbiota advances our knowledge of the antioxidant and anti-inflammatory functions of polyphenols accumulates, there emerges a need to examine the prebiotic role of dietary polyphenols. This review focused onthe role of different types and sources of dietary polyphenols on the modulation of the gut microbiota, their metabolites and how they impact on host health benefits. Inter-dependence between the gut microbiota and polyphenol metabolites and the vital balance between the two in maintaining the host gut homeostasis were discussed with reference to different types and sources of dietary polyphenols. Similarly, the mechanisms behind the health benefits by various polyphenolic metabolites bio-transformed by gut microbiota were also explained. However, further research should focus on the importance of human trials and profound links of polyphenols-gut microbiota-nerve-brain as they provide the key to unlock the mechanisms behind the observed benefits of dietary polyphenols found in vitro and in vivo studies.
10.1016/j.foodres.2021.110189
Exploring the Potential of Breast Microbiota as Biomarker for Breast Cancer and Therapeutic Response.
Dieleman Sabine,Aarnoutse Romy,Ziemons Janine,Kooreman Loes,Boleij Annemarie,Smidt Marjolein
The American journal of pathology
Breast cancer tissue contains its own unique microbiota. Emerging preclinical data indicates that breast microbiota dysbiosis contributes to breast cancer initiation and progression. Furthermore, the breast microbiota may be a promising biomarker for treatment selection and prognosis. Differences in breast microbiota composition have been found between breast cancer subtypes and disease severities that may contribute to immunosuppression, enabling tumor cells to evade immune destruction. Interactions between breast microbiota, gut microbiota, and immune system are proposed, all forming potential targets to increase therapeutic efficacy. In addition, because the gut microbiota affects the host immune system and systemic availability of estrogen and bile acids known to influence tumor biology, gut microbiota modulation could be used to manipulate breast microbiota composition. Identifying breast and gut microbial compositions that respond positively to certain anticancer therapeutics could significantly reduce cancer burden. Additional research is needed to unravel the complexity of breast microbiota functioning and its interactions with the gut and the immune system. In this review, developments in the understanding of breast microbiota and its interaction with the immune system and the gut microbiota are discussed. Furthermore, the biomarker potential of breast microbiota is evaluated in conjunction with possible strategies to target microbiota in order to improve breast cancer treatment.
10.1016/j.ajpath.2021.02.020
Microbiota and Tuberculosis: A Potential Role of Probiotics, and Postbiotics.
Liu Yue,Wang Jiaqi,Wu Changxin
Frontiers in nutrition
Tuberculosis (TB), caused by attacking the lungs and other organs, is one of the most common infectious disease worldwide. According to the WHO's 2020 report, a quarter of the world's population were infected with , and ~1.4 million people died of TB. Therefore, TB is a significant public health concern, which requires cost-effective strategies for prevention and treatment. The microbiota has been considered as a "forgotten organ" and a complex dynamic ecosystem, which plays a significant role in many physiological processes, and its dysbiosis is closely associated with infectious disease. Recently, a few studies have indicated associations between TB and microbiota. This review summarizes studies concerning the alterations of the gut and respiratory microbiota in TB, and their relationship with host susceptibility to infection, indicating that microbiota signatures in different stages in TB progression could be considered as biomarkers for TB diagnosis and control. In addition, the potential role of probiotics and postbiotics in TB treatment was discussed.
10.3389/fnut.2021.626254
Dysbiosis of gut microbiota in inflammatory bowel disease: Current therapies and potential for microbiota-modulating therapeutic approaches.
Alshehri Dikhnah,Saadah Omar,Mosli Mahmoud,Edris Sherif,Alhindi Rashad,Bahieldin Ahmed
Bosnian journal of basic medical sciences
There is a growing body of evidence reinforcing the unique connections between the host microbiome, health, and diseases. Due to the extreme importance of the symbiotic relationship between the intestinal microbiome and the host, it is not surprising that any alteration in the gut microbiota would result in various diseases, including inflammatory bowel disease (IBD), Crohn's disease, (CD) and ulcerative colitis (UC). IBD is a chronic, relapsing-remitting condition that is associated with significant morbidity, mortality, compromised quality of life, and costly medical care. Dysbiosis is believed to exacerbate the progression of IBD. One of the currently used treatments for IBD are anti-tumor necrosis factor (TNF) drugs, representing a biologic therapy that is reported to have an impact on the gut microbiota composition. The efficacy of anti-TNF agents is hindered by the possibility of non-response, which occurs in 10-20% of treated patients, and secondary loss of response, which occurs in up to 30% of treated patients. This underscores the need for novel therapies and studies that evaluate the role of the gut microbiota in these conditions. The success of any therapeutic strategy for IBD depends on our understanding of the interactions that occur between the gut microbiota and the host. In this review, the health and disease IBD-associated microbiota patterns will be discussed, in addition to the effect of currently used therapies for IBD on the gut microbiota composition, as well as new therapeutic approaches that can be used to overcome the current treatment constraints.
10.17305/bjbms.2020.5016
The Interplay between Androgen and Gut Microbiota: Is There a Microbiota-Gut-Testis Axis.
Reproductive sciences (Thousand Oaks, Calif.)
The gut microbiota, a large ecosystem interacting with the host, has been shown to affect the health and fitness of the host-microbial superorganism. Increasing evidence suggests that the gut microbiota communicates with distal organs of the host including the brain, liver, and muscle, as well as testis, through various complex mechanisms. So far, we know that the androgen can markedly remodel the gut microbiota and has initiated an interdisciplinary field termed "microgenderome." More recently, the gut microbiota has been found as a major regulator of androgen production and metabolism in turn and even could trespass the blood-testis barrier (BTB) to regulate spermatogenesis, which largely updates the current knowledge on male reproduction. In this review, we provided a brief overview of the context of the gender bias of diseases related to gut microbiota, the sex dimorphism of gut microbiota, and their relationships with androgen. We also summarized the known interaction between the testis and gut microbiota based on published animal studies and tentatively discussed the hypothesis of microbiota-gut-testis axis. Finally, we highlighted the opportunities and challenges underlying the ongoing research. This knowledge may extend our understanding of the role of gut microbiota in male health and microbiota-related diseases.
10.1007/s43032-021-00624-0
Gut Microbiota and NAFLD: Pathogenetic Mechanisms, Microbiota Signatures, and Therapeutic Interventions.
Hrncir Tomas,Hrncirova Lucia,Kverka Miloslav,Hromadka Robert,Machova Vladimira,Trckova Eva,Kostovcikova Klara,Kralickova Pavlina,Krejsek Jan,Tlaskalova-Hogenova Helena
Microorganisms
Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. Its worldwide prevalence is rapidly increasing and is currently estimated at 24%. NAFLD is highly associated with many features of the metabolic syndrome, including obesity, insulin resistance, hyperlipidaemia, and hypertension. The pathogenesis of NAFLD is complex and not fully understood, but there is increasing evidence that the gut microbiota is strongly implicated in the development of NAFLD. In this review, we discuss the major factors that induce dysbiosis of the gut microbiota and disrupt intestinal permeability, as well as possible mechanisms leading to the development of NAFLD. We also discuss the most consistent NAFLD-associated gut microbiota signatures and immunological mechanisms involved in maintaining the gut barrier and liver tolerance to gut-derived factors. Gut-derived factors, including microbial, dietary, and host-derived factors involved in NAFLD pathogenesis, are discussed in detail. Finally, we review currently available diagnostic and prognostic methods, summarise latest knowledge on promising microbiota-based biomarkers, and discuss therapeutic strategies to manipulate the microbiota, including faecal microbiota transplantation, probiotics and prebiotics, deletions of individual strains with bacteriophages, and blocking the production of harmful metabolites.
10.3390/microorganisms9050957
Gut microbiome, parathyroid hormone, and bone.
Current opinion in nephrology and hypertension
PURPOSE OF REVIEW:Microorganisms in the gut (the 'microbiome') and the metabolites they produce (the 'metabolome') regulate bone mass through interactions between parathyroid hormone (PTH), the immune system, and bone. This review summarizes these data and details how this physiology may relate to CKD-mediated bone disease. RECENT FINDINGS:The actions of PTH on bone require microbial metabolite activation of immune cells. Butyrate is necessary for CD4+ T-cell differentiation, T-reg cell expansion and CD8+ T-cell secretion of the bone-forming factor Wnt10b ligand. By contrast, mice colonized with segmented filamentous bacteria exhibit an expansion of gut Th17 cells and continuous PTH infusion increases the migration of Th17 cells to the bone marrow, contributing to bone resorption. In the context of CKD, a modified diet, frequent antibiotic therapy, altered intestinal mobility, and exposure to multiple medications together contribute to dysbiosis; the implications for an altered microbiome and metabolome on the pathogenesis of renal osteodystrophy and its treatment have not been explored. SUMMARY:As dysregulated interactions between PTH and bone ('skeletal resistance') characterize CKD, the time is ripe for detailed, mechanistic studies into the role that gut metabolites may play in the pathogenesis of CKD-mediated bone disease.
10.1097/MNH.0000000000000714
Lycium barbarum mitigates radiation injury via regulation of the immune function, gut microbiota, and related metabolites.
Zheng Ying,Pang Xu,Zhu Xiaoxia,Meng Zhiyun,Chen Xiaojuan,Zhang Jie,Ding Qianzhi,Li Qi,Dou Guifang,Ma Baiping
Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie
Previous studies have suggested that Lycium barbarum (L. barbarum) has a radioprotective function, although more in-depth investigation is still required. We investigated the radioprotective efficacy of extract of the fruits of L. barbarum (LBE) and its radioprotective mechanisms. Mice were exposed to 8.5 Gy, 5.5 Gy, or 6.0 Gy total body irradiation (TBI), and the survival rate, lymphocyte percentage, amount of cytokines, and viability of the irradiated cells, as well as the gut microbiome and fecal metabolomics were studied. LBE enhanced the survival of the mice exposed to 8.5 Gy γ-ray TBI or 5.5 Gy X-ray TBI. After 6.0 Gy γ-ray TBI, LBE exhibited good immunomodulatory properties, mainly characterized by the accelerated recovery of lymphocyte percentages, and the enhanced expression of immune-related cytokines. LBE reconstituted the gut microbiota of irradiated mice, increased the relative abundance of potentially beneficial genera (e.g., Turicibacter, Akkermansia), and decreased the relative abundance of potentially harmful bacterial genera (e.g., Rikenellaceae_RC9_gut_group). Beneficial regulatory effects of LBE on the host metabolites were also noted, and the major upregulated metabolites induced by LBE, such as Tetrahydrofolic acid and N-ornithyl-L-taurine, were positively correlated with the immune factor interleukin (IL)-6. In vitro, LBE also increased the vitality of rat small intestinal epithelial cells (IEC-6) after 4.0 Gy γ-ray irradiation and promoted the growth of Akkermansia muciniphila. These results confirmed a radioprotective function of LBE and indicated that the radioprotective mechanism may be due to immunomodulation and the synergistically modulating effect on the gut microbiota and related metabolites.
10.1016/j.biopha.2021.111654
Interplay between gut microbiota, bone health and vascular calcification in chronic kidney disease.
Rodrigues Fernanda G,Ormanji Milene S,Heilberg Ita P,Bakker Stephan J L,de Borst Martin H
European journal of clinical investigation
Deregulations in gut microbiota may play a role in vascular and bone disease in chronic kidney disease (CKD). As glomerular filtration rate declines, the colon becomes more important as a site of excretion of urea and uric acid, and an increased bacterial proteolytic fermentation alters the gut microbial balance. A diet with limited amounts of fibre, as well as certain medications (eg phosphate binders, iron supplementation, antibiotics) further contribute to changes in gut microbiota composition among CKD patients. At the same time, both vascular calcification and bone disease are common in patients with advanced kidney disease. This narrative review describes emerging evidence on gut dysbiosis, vascular calcification, bone demineralization and their interrelationship termed the 'gut-bone-vascular axis' in progressive CKD. The role of diet, gut microbial metabolites (ie indoxyl sulphate, p-cresyl sulphate, trimethylamine N-oxide (TMAO) and short-chain fatty acids (SCFA)), vitamin K deficiency, inflammatory cytokines and their impact on both bone health and vascular calcification are discussed. This framework may open up novel preventive and therapeutic approaches targeting the microbiome in an attempt to improve cardiovascular and bone health in CKD.
10.1111/eci.13588
A Systematic Review of Dietary Influences on Fecal Microbiota Composition and Function among Healthy Humans 1-20 Years of Age.
Advances in nutrition (Bethesda, Md.)
Diet is a key modulator of fecal microbiota composition and function. However, the influence of diet on the microbiota from toddlerhood to adolescence and young adulthood is less well studied than for infancy and adulthood. We aimed to complete a qualitative systematic review of the impacts of diet on the fecal microbiota of healthy humans 1-20 y of age. English-language articles, published after 2008, indexed in the PubMed/MEDLINE, Cochrane, Web of Science, and Scopus databases were searched using keywords and Medical Subject Headings terms. Quality assessment of included studies was conducted using the Quality Criteria Checklist derived from the Nutrition Evidence Library of the Academy of Nutrition and Dietetics. A total of 973 articles were identified through database searching and 3 additional articles were included via cross-reference. Subsequent to de-duplication, 723 articles were screened by title and abstract, of which 709 were excluded based on inclusion criteria established a priori. The remaining 14 studies were independently screened by 2 reviewers for final inclusion. Included studies were published between 2010 and 2019 and included 8 comparative cross-sectional studies, 4 cross-sectional studies, 1 randomized crossover study, and 1 substudy of a randomized 2-period crossover trial. Associations of a diet rich in indigestible plant polysaccharides with Prevotella, or with an enterotype dominated by this genus, often comprised of the species Prevotella copri, were observed. In addition, associations of a high-fat and -sugar diet with Bacteroides, or with an enterotype dominated by this genus, were observed predominantly in comparative cross-sectional and cross-sectional studies spanning the ages of 1-15 y. This review identified a gap in the literature for ages 16-20 y. In addition, randomized controlled trials for dietary intervention are needed to move from association-based observations to causal relations between diet and microbiota composition and function. This systematic review was registered at www.crd.york.ac.uk/prospero as CRD42020129824.
10.1093/advances/nmab047
Daily full spectrum light exposure prevents food allergy-like allergic diarrhea by modulating vitamin D and microbiota composition.
Chen Po-Jung,Nakano Toshiaki,Lai Chia-Yun,Chang Kuei-Chen,Chen Chao-Long,Goto Shigeru
NPJ biofilms and microbiomes
The importance of sun exposure on human health is well recognized, and a recent trend in the avoidance of sun exposure has led to the risk of missing the beneficial effects such as vitamin D biogenesis. Vitamin D insufficiency is one of the risk factors for the development of food allergies (FAs), and vitamin D status controls gut homeostasis by modulating the microbiota. This study aimed to explore the impact of daily full spectrum light exposure (phototherapy) on the pathogenesis of FAs. Phototherapy ameliorated allergic diarrhea and improved FA-associated vitamin D insufficiency and dysbiosis. Fecal microbiota transplantation (FMT) of FA donor feces induced allergic diarrhea with OVA-specific IgE elevation in naïve mice. In contrast, FMT of naïve donor feces ameliorated allergic diarrhea in established FA mice, suggesting the involvement of the microbiota composition in FA. Phototherapy is an alternative approach for the prevention of FA-like allergic diarrhea through the modulation of vitamin D status and microbiota composition.
10.1038/s41522-021-00213-8
Bionic Tiger-Bone Powder Improves Bone Microstructure and Bone Biomechanical Strength of Ovariectomized Rats.
Ren Shanwu,Jiao Guangjun,Zhang Lu,You Yunhao,Chen Yunzhen
Orthopaedic surgery
OBJECTIVE:To study the curative effect of bionic tiger-bone powder on osteoporosis in ovariectomized rats and investigate its mechanism. METHODS:Overall, a 120 female Wistar rats were randomly divided into Sham (sham-operated group), ovariectomy (OVX, ovariectomized group), TB (bionic tiger-bone powder treatment group after ovariectomy) and TB + VD groups (bionic tiger-bone powder + vitamin D treatment group after ovariectomy). The osteoporotic rat model was established 3 months after ovariectomy, and rats were intragastrically administrated with the corresponding drugs. Serum and bone tissue samples were collected from 10 rats in each group at weeks 4, 12 and 24 after intragastric administration. The bone microstructure of L vertebrae was analyzed by MicroCT, the biomechanical strength of left femurs was measured by the three-point bending test, and serum bone metabolism markers (P1NP and CTX) were detected by ELISA. Changes in bone collagen were analyzed by Masson's trichrome staining and hydroxyproline detection, and members of the BMP2/SMAD/RUNX2 and OPG/RANKL/RANK signal pathways were detected by immunoblotting. RESULTS:Compared with the OVX group, the serum level of P1NP in the TB and TB + VD groups was higher (P < 0.05), while the CTX level was lower (P < 0.05). Bone collagen fiber structures in the TB and TB + VD groups were repaired, and the collagen content was significantly higher than that in the OVX group (P < 0.05). In the TB group, BMP-2, P-SMAD1/5, RUNX2 and OPG levels were increased in bone tissue (P < 0.01), RANKL levels were decreased (P < 0.01), and the bone microstructure and biomechanical strength were improved. CONCLUSION:Bionic tiger-bone powder promotes osteogenesis by activating the BMP2/SMAD/RUNX2 signaling pathway, suppresses osteoclasts by downregulating the OPG/RANK/RANKL signaling pathway, increases bone collagen content, and improves bone microstructure and bone biomechanical strength.
10.1111/os.12954
Fecal Microbiota in Untreated Children With Juvenile Idiopathic Arthritis: A Comparison With Healthy Children and Healthy Siblings.
Öman Anders,Dicksved Johan,Engstrand Lars,Berntson Lillemor
The Journal of rheumatology
OBJECTIVE:Changes in the composition of gut microbiota have been suggested to be associated with juvenile idiopathic arthritis (JIA). The objective in this study was to investigate if the diversity and composition of the fecal microbiota differed between children with JIA and healthy controls (HCs), and if the microbiota differed between children with JIA and their healthy siblings. METHODS:In this multicenter, case-control study, fecal samples were collected from 75 children with JIA and 32 HCs. Eight of the HCs were siblings to 8 children with JIA, and they were compared only pairwise with their siblings. The microbiota was determined using sequencing amplicons from the V3 and V4 regions of the 16S rRNA gene. Alpha diversity, community composition of microbiota, and relative abundances of taxa were compared between children with JIA and healthy unrelated controls as well as between children with JIA and healthy siblings. RESULTS:Our data revealed no significant differences in α-diversity or community composition of microbiota between children with JIA, healthy unrelated controls, or healthy siblings. Analyses of relative abundances of phyla, families, and genera identified trends of differing abundances of some taxa in children with JIA, in comparison with both HCs and healthy siblings, but none of these findings were significant after adjustment for multiple comparisons. CONCLUSION:There were no significant differences in the composition of fecal microbiota in children with JIA compared with HCs. The composition of microbiota in children with JIA did not differ significantly from that in their healthy siblings.
10.3899/jrheum.200551
Shift in skin microbiota and immune functions of zebrafish after combined exposure to perfluorobutanesulfonate and probiotic Lactobacillus rhamnosus.
Ecotoxicology and environmental safety
Dysbiosis of fish skin microbiome and immunity by environmental pollutants are rarely studied in toxicological research in spite of their importance for fish health. In the present study, adult zebrafish were exposed to 0 and 10 μg/L of perfluorobutanesulfonate (PFBS) for 40 days, with or without the supplementation of probiotic Lactobacillus rhamnosus, with objectives to explore the interaction between PFBS pollutant and probiotic bacteria on skin mucosal microbiota and immune response. Amplicon sequencing analysis found that PFBS alone significantly disturbed the microbial community composition and abundance on the skin, favoring the growth of stress-tolerant bacteria (e.g., Deinococcus and Enhydrobacter genera). However, the administration of probiotic inhibited the dysbiosis of PFBS and shaped the skin microbiome in the combined exposure group. PFBS single exposure also promoted the production of mucus on the skin of male zebrafish, which may be related to the growth of Limnobacter bacteria. In contrast, probiotic supplements remarkably improved the immune functions in male skin mucus from the combined group, as evidenced by the consistent increases in lysozyme activity, immunoglobulin concentrations and peroxidase activity. Overall, the present study provides the first clue about the singular and combined effects of PFBS and probiotic on skin microbiota and immunity, highlighting the beneficial action of probiotic L. rhamnosus against PFBS stress.
10.1016/j.ecoenv.2021.112310
Gut microbiota and cardiovascular diseases axis.
Moldovan Dora C,Ismaiel Abdulrahman,Fagoonee Sharmila,Pellicano Rinaldo,Abenavoli Ludovico,Dumitrascu Dan L
Minerva medica
Gut microbiota, a term that includes microorganisms present in the gastrointestinal tract, has become very attractive lately due to its propensity to act as a virtual organ with endocrine functions, generating various bio-active metabolites, while playing an important role in human health and diseases, including cardiovascular diseases (CVDs). Focusing on the latter field, gastrointestinal dysbiosis that is the imbalance in the gut microbiota composition has been linked to various pathologies such as hypertension, atherosclerosis, myocardial infarction and heart failure. Several pathways were demonstrated to play a role in the complex and intertwined association between the gut microbiota and host, including metabolic endotoxemia, alteration of pattern recognition receptors and short-chain fatty acids, uremic toxins, bile acids and trimethylamine-N-oxide levels, leading to CVDs. Understanding these pathways can allow the identification of metabolites that could be useful predictors for detecting incipient CVDs stages and potential therapeutic targets. In this review, we summarize the pathways associating the gut microbiota with CVDs.
10.23736/S0026-4806.21.07527-3
The relationship between gut microbiota, short-chain fatty acids and type 2 diabetes mellitus: the possible role of dietary fibre.
Salamone Dominic,Rivellese Angela Albarosa,Vetrani Claudia
Acta diabetologica
Gut microbiota and its metabolites have been shown to influence multiple physiological mechanisms related to human health. Among microbial metabolites, short-chain fatty acids (SCFA) are modulators of different metabolic pathways. On the other hand, several studies suggested that diet might influence gut microbiota composition and activity thus modulating the risk of metabolic disease, i.e. obesity, insulin resistance and type 2 diabetes. Among dietary component, dietary fibre may play a pivotal role by virtue of its prebiotic effect on fibre-fermenting bacteria, that may increase SCFA production. The aim of this review was to summarize and discuss current knowledge on the impact of dietary fibre as modulator of the relationship between glucose metabolism and microbiota composition in humans. More specifically, we analysed evidence from observational studies and randomized nutritional intervention investigating the relationship between gut microbiota, short-chain fatty acids and glucose metabolism. The possible mechanisms behind this association were also discussed.
10.1007/s00592-021-01727-5
Genetic and epigenetic perspective of microbiota.
Celiker Cigdem,Kalkan Rasime
Applied microbiology and biotechnology
The gut microbiota has an extremely important role within the body and it is necessary for the regulation of the metabolism of the host and also for the development of metabolic diseases such as obesity. Here, we show several different factors leading to obesity such as epigenetic changes and how they result in differences to occur in the gut microbiota, along with gut dysbiosis which is caused by disturbances in the microbiota homeostasis. Several studies have been explained in this paper, providing evidence in how these findings can actually decrease the susceptibility of obesity, whether it be by changing an individual's diet pattern or observing the epigenetic changes which are taking place. KEY POINTS: • The microbiota depends on an individual's diet, lifestyle, environment, genetics and epigenetic profile. • Changes of the gut microbiota can increase obesity susceptibility. • Non-coding RNA has an important role in the metabolic homeostasis in check so if a disturbance occurs it can lead to resistance to obesity.
10.1007/s00253-020-10849-9
Fungi of the human gut microbiota: Roles and significance.
Pérez J Christian
International journal of medical microbiology : IJMM
It is becoming increasingly clear that fungi are important components of the gut microbiota. Fungi residing in the human intestine, for example, elicit the induction of T helper 17 cells, which are central orchestrators of protective immune responses. Likewise, fungal members of the intestinal microbiota have been shown to influence the immunological responses of the mammalian host by dampening or promoting local inflammatory responses. Here I review some of the latest developments regarding symbiotic fungi of the gastrointestinal tract and the consequences that fungal dysbiosis may have on human health. A major focus of the review is on the relationship between Candida albicans, the most prominent fungus inhabiting the human gut, and the mammalian host. Advances in the field underscore the need to further investigate the fungi that inhabit the human body to understand how the mixed array of microbes that constitute our microbiota contribute to health and disease.
10.1016/j.ijmm.2021.151490
Microbiome-metabolomic analyses of the impacts of dietary stachyose on fecal microbiota and metabolites in infants intestinal microbiota-associated mice.
Xi Menglu,Tang Haixia,Zhang Yan,Ge Wupeng,Chen Ying,Cui Xiuxiu
Journal of the science of food and agriculture
BACKGROUND:The intestinal microbiota and metabolites play an important role in human health and immunity. However, few studies have investigated the long-term effects of stachyose on the human intestinal microbiota and metabolism. Therefore, in this study, the feces of infants were transplanted into germ-free mice, and the effect of long-term stachyose intake on intestinal metabolism was examined by comparing the results of microbiome and metabolome analyses. Ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was used to study the effects of stachyose intake on the metabolites and metabolic pathways of the transplanted human intestinal microbiota. RESULTS:We observed that stachyose significantly altered the composition of the intestinal microbiota and metabolites, up-regulated production of the metabolite taurocholic acid, down-regulated amino acid metabolism, and significantly regulated the metabolism of taurine and hydroxytaurine, pantothenate and coenzyme A (CoA) biosynthesis, and other signaling pathways. CONCLUSION:These findings may provide a basis for elucidating the mechanism by which stachyose promotes host health. © 2020 Society of Chemical Industry.
10.1002/jsfa.10963
Crosstalk between circadian rhythms and the microbiota.
Pearson James Alexander,Wong Florence Susan,Wen Li
Immunology
Circadian rhythms influence daily molecular oscillations in gene/protein expression and aspects of biology and physiology, including behaviour, body temperature and sleep-wake cycles. These circadian rhythms have been associated with a number of metabolic, immune and microbial changes that correlate with health and susceptibility to disease, including infection. While light is the main inducer of circadian rhythms, other factors, including the microbiota, can have important effects on peripheral rhythms. The microbiota have been of significant interest to many investigators over the past decade, with the development of molecular techniques to identify large numbers of species and their function. These studies have shown microbial associations with disease susceptibility, and some of these have demonstrated that alterations in microbiota cause disease. Microbial circadian oscillations impact host metabolism and immunity directly and indirectly. Interestingly, microbial oscillations also regulate host circadian rhythms, and the host circadian rhythms in turn modulate microbial composition. Thus, it is of considerable interest and importance to understand the crosstalk between circadian rhythms and microbiota and especially the microbial influences on the host. In this review, we aim to discuss the role of circadian microbial oscillations and how they influence host immunity. In addition, we discuss how host circadian rhythms can also modulate microbial rhythms. We also discuss potential connections between microbes and circadian rhythms and how these may be used therapeutically to maximize clinical success.
10.1111/imm.13278
The gut microbiota alteration and the key bacteria in Astragalus polysaccharides (APS)-improved osteoporosis.
Liu Junsheng,Liu Jun,Liu Liu,Zhang Guangwen,Zhou Aimei,Peng Xichun
Food research international (Ottawa, Ont.)
Osteoporosis is a worldwide epidemic, and certain functional foods can alleviate osteoporosis with great efficiency. Here, in a dexamethasone-induced osteoporosis rat model, it was proved that APS could restore the bone mineral density (BMD) and repair the impairment of bone microarchitecture, two major features of osteoporosis. In APS-treated rats, acid phosphatase 5 (ACP5) and pro-inflammatory cytokines (TNF-α and IL-2) were significantly decreased. This suggested that APS might improve osteoporosis by inhibiting osteoclastogenesis and preventing inflammation. Further analysis on the bacterial community revealed that the structure of gut microbiota was dramatically changed by APS, and 13 bacteria (such as c_Bacteroidia, p_Bacteroidetes, and g_Allpprevotella) could serve as biomarkers for APS-improved osteoporosis. Furthermore, five genera (uncultured_bacterium_f_Ruminococcaceae, Alloprevotella, Ruminococcaceae_UCG-014, Blautia and Lactobacillus) were inferred as the key bacteria in APS-improved osteoporosis. In conclusion, APS-modified gut microbiota and the potential key bacteria to alleviate osteoporosis, as well as its relationship with improved osteoporosis, were investigated in our present study. Our results will help to understand how APS improves osteoporosis by regulating gut microbiota and contribute to the development and application of functional foods to alleviate refractory osteoporosis by regulating targeted intestinal bacteria.
10.1016/j.foodres.2020.109811