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Linking energy sensing to suppression of JAK-STAT signalling: A potential route for repurposing AMPK activators? Speirs Claire,Williams Jamie J L,Riches Kirsten,Salt Ian P,Palmer Timothy M Pharmacological research Exaggerated Janus kinase-signal transducer and activator of transcription (JAK-STAT) signalling is key to the pathogenesis of pro-inflammatory disorders, such as rheumatoid arthritis and cardiovascular diseases. Mutational activation of JAKs is also responsible for several haematological malignancies, including myeloproliferative neoplasms and acute lymphoblastic leukaemia. Accumulating evidence links adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK), an energy sensor and regulator of organismal and cellular metabolism, with the suppression of immune and inflammatory processes. Recent studies have shown that activation of AMPK can limit JAK-STAT-dependent signalling pathways via several mechanisms. These novel findings support AMPK activation as a strategy for management of an array of disorders characterised by hyper-activation of the JAK-STAT pathway. This review discusses the pivotal role of JAK-STAT signalling in a range of disorders and how both established clinically used and novel AMPK activators might be used to treat these conditions. 10.1016/j.phrs.2017.10.001
Metformin and its therapeutic applications in autoimmune inflammatory rheumatic disease. Kim Ji-Won,Choe Jung-Yoon,Park Sung-Hwan The Korean journal of internal medicine Metformin is a first-line therapeutic agent for type 2 diabetes. Apart from its glucose-lowering effect, metformin is attracting interest regarding possible therapeutic benefits in various other conditions. As metformin regulates cell metabolism, proliferation, growth, and autophagy, it may also modulate immune cell functions. Given that metformin acts on multiple intracellular signaling pathways, including adenosine monophosphate (AMP)-activated protein kinase (AMPK) activation, and that AMPK and its downstream intracellular signaling control the activation and differentiation of T and B cells and inflammatory responses, metformin may exert immunomodulatory and anti- inflammatory effects. The efficacy of metformin has been investigated in preclinical and clinical studies on rheumatoid arthritis, osteoarthritis, systemic lupus erythematosus, Sjögren's syndrome, scleroderma, ankylosing spondylitis, and gout. In this review, we discuss the potential mechanisms through which metformin exerts its therapeutic effects in these diseases, focusing particularly on rheumatoid arthritis and osteoarthritis. 10.3904/kjim.2021.363
Metformin and omega-3 fish oil elicit anti-inflammatory effects via modulation of some dysregulated micro RNAs expression and signaling pathways in experimental induced arthritis. El-Sayyad Shorouk M,Ali Mennatallah A,Kandil Lamia S,Ragab Ghada M,Abdelhamid Ibrahim Sherihan S International immunopharmacology OBJECTIVE:Rheumatoid arthritis is a progressive inflammatory disease with multiple dysfunctional intracellular signaling pathways that necessitate new approaches for its management. Hence, the study aimed to inspect the ability of the combination therapy of metformin and omega-3 to modulate different signaling pathways and micro RNAs such as (miR-155, miR-146a and miR-34) as new targets in order to mitigate adjuvant-induced arthritis and compare their effect to that of methotrexate. METHODS:Fourteen days post adjuvant injection, Sprague-Dawley rats were treated orally with metformin (200 mg/kg/day) and/or omega-3 (300 mg/kg/day) or intraperitoneally with methotrexate (2 mg/kg/week) for 4 weeks. RESULTS AND CONCLUSION:All drug treatments amended the arthrogram score and hind paw swelling as well as decreased serum tumor necrosis factor (TNF)-α and interleukin (IL)-1β levels. On the molecular level, all therapies activated phospho-5'adenosine monophosphate-activated protein kinase (p-AMPK) and protein phosphatase 2A (PP2A), while they inhibited phospho-mammalian target of rapamycin (p-mTOR), phospho-signal transducers and activators of transcription (p-STAT3), nuclear factor (NF)-κB p65 subunit, phosho38 mitogen-activated protein kinase (p38 MAPK) and phospho- c-Jun N-terminal kinase (p-JNK). In addition, they decreased the elevated expression level of miRNA-155, 146a and increased the expression level of miRNA-34 and they decreased the expression level of retinoic acid receptor related orphan receptor γT (RORγT) and increased that of fork head box P3 (FOXP3), correcting Th17/Treg cells balance. On most of the aforementioned parameters, the effect of the combination therapy was comparable to that of methotrexate, emphasizing that this combination possesses better additive anti-inflammatory effect than either drug when used alone. In addition, the combination was capable of normalizing the serum transaminases levels as compared to untreated group offering hepatoprotective effect and suggesting the possibility of its use as a replacement therapeutic strategy for MTX in rheumatoid arthritis. 10.1016/j.intimp.2020.107362
Metformin: A Potential Therapeutic Tool for Rheumatologists. Salvatore Teresa,Pafundi Pia Clara,Galiero Raffaele,Gjeloshi Klodian,Masini Francesco,Acierno Carlo,Di Martino Anna,Albanese Gaetana,Alfano Maria,Rinaldi Luca,Sasso Ferdinando Carlo Pharmaceuticals (Basel, Switzerland) Metformin is an oral antihyperglycemic drug widely used to treat type 2 diabetes, acting via indirect activation of 5' Adenosine Monophosphate-activated Protein Kinase (AMPK). Actually, evidence has accumulated of an intriguing anti-inflammatory activity, mainly mediated by AMPK through a variety of mechanisms such as the inhibition of cytokine-stimulated Nuclear Factor-κB (NF-κB) and the downregulation of the Janus Kinase/Signal Transducer and Activator of Transcription (JAK/STAT) signaling pathways. Moreover, AMPK plays an important role in the modulation of T lymphocytes and other pivotal cells of the innate immune system. The current understanding of these AMPK effects provides a strong rationale for metformin repurposing in the management of autoimmune and inflammatory conditions. Several studies demonstrated metformin's beneficial effects on both animal and human rheumatologic diseases, especially on rheumatoid arthritis. Unfortunately, even though data are large and remarkable, they almost exclusively come from experimental investigations with only a few from clinical trials. The lack of support from prospective placebo-controlled trials does not allow metformin to enter the therapeutic repertoire of rheumatologists. However, a large proportion of rheumatologic patients can currently benefit from metformin, such as those with concomitant obesity and type 2 diabetes, two conditions strongly associated with rheumatoid arthritis, osteoarthritis, and gout, as well as those with diabetes secondary to steroid therapy. 10.3390/ph13090234
Suppression of experimental arthritis through AMP-activated protein kinase activation and autophagy modulation. Yan Huimin,Zhou Hui-Fang,Hu Ying,Pham Christine T N Journal of rheumatic diseases and treatment Autophagy plays a central role in various disease processes. However, its contribution to inflammatory arthritides such as rheumatoid arthritis (RA) is unclear. We observed that autophagy is engaged in the K/BxN serum transfer model of RA but autophagic flux is severely impaired. Metformin is an anti-diabetic drug that has been shown to stimulate autophagy. Induction of autophagic flux, through metformin-mediated AMP-activated protein kinase (AMPK) activation and interruption of mammalian target of rapamycin (mTOR) signaling mitigated the inflammation in experimental arthritis. Further investigation into the effects of metformin suggest that the drug directly activates AMPK and dose-dependently suppressed the release of TNF-α, IL-6, and MCP-1 by macrophages while enhancing the release of IL-10 , metformin treatment significantly suppressed clinical arthritis and inflammatory cytokine production. Mechanistic studies suggest that metformin exerts its anti-inflammatory effects by correcting the impaired autophagic flux observed in the K/BxN arthritis model and suppressing NF-κB-mediated signaling through selective degradation of IκB kinase (IKK). These findings establish a central role for autophagy in inflammatory arthritis and argue that autophagy modulators such as metformin may represent potential therapeutic agents for the treatment of RA. 10.23937/2469-5726/1510005
Metformin downregulates Th17 cells differentiation and attenuates murine autoimmune arthritis. Kang Kwi Young,Kim Young-Kyun,Yi Hyoju,Kim Juryun,Jung Hae-Rin,Kim In Je,Cho Jae-Hyoung,Park Sung-Hwan,Kim Ho-Youn,Ju Ji Hyeon International immunopharmacology INTRODUCTION:This study was undertaken to determine whether metformin has anti-inflammatory effects in the collagen antibody-induced arthritis (CAIA) murine model. The effect of metformin on Th17 cell differentiation was also investigated. METHODS:CAIA mice were treated with 100 and 150 mg/kg i.p. metformin (low- and high-dose groups, respectively). Arthritis activity and histological joint destruction were studied. Flow cytometry was used to (i) determine RORγt-expressing CD4+ percentages in draining axillary lymph nodes (ALNs) from metformin-treated and untreated mice with CAIA, (ii) determine Th17 percentages in splenic CD4+ T cells cultured ex vivo for 3 days in Th17-differentiation-inducing conditions, and (iii) determine the percentages of RORγt+CD4+ T cells when normal splenic T cells from DBA/1 mice were cultured in Th17-differentiation-inducing conditions together with various metformin doses. Western blot analysis was used to assess the intracellular signaling of the metformin-treated splenocytes. RESULTS:Metformin attenuated both arthritis scores and bone destruction in CAIA mice, decreased the serum levels of the pro-inflammatory cytokines, TNF-α and IL-1, and reduced the number of RORγt+CD4+ T cells in the ALNs. Splenocytes from metformin-treated CAIA mice differentiated less readily into Th17 cells upon ex vivo stimulation. Metformin treatment of normal cells cultured in Th17-differentiation-inducing conditions decreased the number of RORγt-expressing CD4+ cells in a dose-dependent manner and downregulated STAT3 phosphorylation via the AMPK pathway. CONCLUSIONS:Metformin had an anti-inflammatory effect on murine autoimmune arthritis due to the inhibition of Th17 cell differentiation. Metformin may have a possible therapeutic value for treatment of rheumatoid arthritis. 10.1016/j.intimp.2013.03.020
Metformin one in a Million Efficient Medicines for Rheumatoid Arthritis Complications: Inflammation, Osteoblastogenesis, Cardiovascular Disease, Malignancies. Rajaei Elham,Haybar Habib,Mowla Karim,Zayeri Zeinab D Current rheumatology reviews BACKGROUND:Rheumatoid arthritis is a widespread autoimmune disease and inflammation and bone destruction are two main issues in rheumatoid arthritis. OBJECTIVE:To discussing metformin effects on rheumatoid arthritis complications. METHODS:We conducted a narrative literature search including clinical trials, experimental studies on laboratory animals and cell lines. Our search covered Medline, PubMed and Google Scholar databases from 1999 until 2018. We used the terms" Metformin; Rheumatoid arthritis; Cardiovascular disease; Cancer; Osteoblastogenesis. DISCUSSION:Inflammatory pro-cytokines such as Interlukin-6 play important roles in T. helper 17 cell lineage differentiation. Interlukin-6 and Tumor Necrosis Factor-α activate Janus kinase receptors signal through signaling transducer and activator of transcription signaling pathway which plays important role in inflammation, bone destruction and cancer in rheumatoid arthritis patients. Interlukin-6 and Tumor Necrosis Factor-α synergistically activate signaling transducer and activator of transcription and Nuclear Factor-kβ pathways and both cytokines increase the chance of cancer development in rheumatoid arthritis patients. Metformin is AMPK activators that can suppress mTOR, STAT3 and HIF-1 so AMPK activation plays important role in suppressing inflammation and osteoclastogenesis and decreasing cancer. CONCLUSION:Metformin effect on AMPK and mTOR pathways gives the capability to change Treg/Th17 balance and decrease Th17 differentiation and inflammation, osteoclastogenesis and cancers in RA patients. Metformin can be useful in protecting bones especially in first stages of RA and it can decrease inflammation, CVD and cancer in RA patients so Metformin beside DAMARs can be useful in increasing RA patients' life quality with less harm and cost. 10.2174/1573397114666180717145745
Metformin, an AMPK Activator, Inhibits Activation of FLSs but Promotes HAPLN1 Secretion. Chen Yong,Qiu Fujuan,Yu Beijia,Chen Yanjuan,Zuo Fangfang,Zhu XiaoYu,Nandakumar Kutty Selva,Xiao Changhong Molecular therapy. Methods & clinical development AMP-activated protein kinase (AMPK) is essential for maintaining energy balance and has a crucial role in various inflammatory pathways. In this study, AMPK levels positively correlated with many inflammatory indexes in rheumatoid arthritis (RA) patients, especially in the affected synovium. In RA sera, a positive correlation between phosphorylated (p-)AMPK-α1 levels and DAS28 (disease activity score 28) activity (r = 0.270, p < 0.0001) was found. Similarly, a positive correlation was observed between AMPK-α1 and tumor necrosis factor α (TNF-α) levels (r = 0.460, p = 0.0002). Differentially expressed genes between osteoarthritis (OA) and RA synovium from NCBI GEO profiles and our RNA sequencing data suggested activation of metabolic pathways specific to RA-fibroblast-like synoviocytes (FLSs). AMPK-α1 was highly expressed in the synovium of RA but not OA patients. An AMPK activator, metformin, inhibited FLS proliferation at higher but not lower concentrations, whereas the inhibitor dorsomorphin promoted the proliferation of RA-FLSs. Interestingly, both metformin and dorsomorphin inhibited the migration of RA-FLSs. After metformin treatment, expression of interleukin 6 (IL-6), TNF-α, and IL-1β were significantly downregulated in RA-FLSs; however, increased expression of p-AMPK-α1, protein kinase A (PKA)-α1, and HAPLN1 (hyaluronan and proteoglycan link protein 1) was observed. Increased levels of HAPLN1 in RA-FLSs by an AMPK activator could potentially be beneficial in protecting the joints. Hence, our results demonstrate the potential of an AMPK activator as a therapeutic for RA. 10.1016/j.omtm.2020.05.008