Predictive Modeling of MAFLD Based on Hsp90α and the Therapeutic Application of Teprenone in a Diet-Induced Mouse Model

Background and AimsThe heat shock protein (Hsp) 90α is induced by stress and regulates inflammation through multiple pathways. Elevated serum Hsp90α had been found in nonalcoholic steatohepatitis (NASH). Geranylgeranylacetone (GGA, also called teprenone) is a terpenoid derivative. It was reported to induce Hsp and alleviate insulin resistance. We aimed to evaluate the Hsp90α as a biomarker in predicting metabolic-associated fatty liver disease (MAFLD) and define the therapeutic effects of geranylgeranylacetone for the disease.MethodsA clinical study was conducted to analyze the elements associated with Hsp90α, and a predictive model of MAFLD was developed based on Hsp90α. The histopathological correlation between Hsp90α and MAFLD was investigated through a diet-induced mouse model. Furthermore, GGA was applied to the mouse model.ResultsSerum Hsp90α was increased in patients with MAFLD. A positive linear relationship was found between age, glycosylated hemoglobin (HbA1c), MAFLD, and serum Hsp90α. Meanwhile, a negative linear relationship with body mass index (BMI) was found. A model using Hsp90α, BMI, HbA1c, and ALT was established for predicting MAFLD. The area under the receiver operating characteristic (ROC) curves was 0.94 (95% CI 0.909–0.971, p = 0.000). The sensitivity was 84.1%, and the specificity was 93.1%. In vitro experiments, GGA induced Hsp90α in steatosis cells. In the mice model, Hsp90α decreased in the GGA treatment group. Hepatic steatosis, inflammation, insulin resistance, and glucose intolerance were improved in the GGA-treated group. Serum Hsp90α was positively correlated with steatohepatitis activity according to hepatic histopathology.ConclusionsSerum Hsp90α was elevated in MAFLD, and a positive correlation between serum Hsp90α and the grade of activity of steatohepatitis was observed. The model using BMI, HbA1c, and alanine aminotransferase (ALT) had a good value to predict MAFLD. The findings also revealed the effectiveness of GGA in the treatment of MAFLD.

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A novel phosphoramide compound, DCZ0805, shows potent anti-myeloma activity via the NF-κB pathway

Cancer Cell International ◽

10.1186/s12935-021-01973-1 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Xuejie Gao ◽

Bo Li ◽

Anqi Ye ◽

Houcai Wang ◽

Yongsheng Xie ◽

...

Keyword(s):

Mouse Model ◽

Tumor Burden ◽

High Rate ◽

Cell Counting ◽

Tumor Xenograft ◽

Luciferase Reporter ◽

Therapeutic Effects ◽

Xenograft Mouse Model

Abstract Background Multiple myeloma (MM) is a highly aggressive and incurable clonal plasma cell disease with a high rate of recurrence. Thus, the development of new therapies is urgently needed. DCZ0805, a novel compound synthesized from osalmide and pterostilbene, has few observed side effects. In the current study, we intend to investigate the therapeutic effects of DCZ0805 in MM cells and elucidate the molecular mechanism underlying its anti-myeloma activity. Methods We used the Cell Counting Kit-8 assay, immunofluorescence staining, cell cycle assessment, apoptosis assay, western blot analysis, dual-luciferase reporter assay and a tumor xenograft mouse model to investigate the effect of DCZ0805 treatment both in vivo and in vitro. Results The results showed that DCZ0805 treatment arrested the cell at the G0/G1 phase and suppressed MM cells survival by inducing apoptosis via extrinsic and intrinsic pathways. DCZ0805 suppressed the NF-κB signaling pathway activation, which may have contributed to the inhibition of cell proliferation. DCZ0805 treatment remarkably reduced the tumor burden in the immunocompromised xenograft mouse model, with no obvious toxicity observed. Conclusion The findings of this study indicate that DCZ0805 can serve as a novel therapeutic agent for the treatment of MM.

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Tolerogenic Splenic IDO+Dendritic Cells from the Mice Treated with Induced-Treg Cells Suppress Collagen-Induced Arthritis

Journal of Immunology Research ◽

10.1155/2014/831054 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12 ◽

Cited By ~ 9

Author(s):

Jie Yang ◽

Yiming Yang ◽

Huahua Fan ◽

Hejian Zou

Keyword(s):

Dendritic Cells ◽

Immune Responses ◽

Foxp3 Expression ◽

Treated Group ◽

Treg Cells ◽

Therapeutic Effects ◽

Dependent Manner ◽

Collagen Induced Arthritis

TGF-β-induced regulatory T cells (iTregs) retain Foxp3 expression and immune-suppressive activity in collagen-induced arthritis (CIA). However, the mechanisms whereby transferred iTregs suppress immune responses, particularly the interplay between iTregs and dendritic cells (DCs)in vivo, remain incompletely understood. In this study, we found that after treatment with iTregs, splenic CD11c+DCs, termed “DCiTreg,” expressed tolerogenic phenotypes, secreted high levels of IL-10, TGF-β, and IDO, and showed potent immunosuppressive activityin vitro. After reinfusion with DCiTreg, marked antiarthritic activity improved clinical scores and histological end-points were observed. The serological levels of inflammatory cytokines and anti-CII antibodies were low and TGF-βproduction was high in the DCiTreg-treated group. DCiTregalso induced new iTregsin vivo. Moreover, the inhibitory activity of DCiTregon CIA was lost following pretreatment with the inhibitor of indoleamine 2,3-dioxygenase (IDO). Collectively, these findings suggest that transferred iTregs could induce tolerogenic characteristics in splenic DCs and these cells could effectively dampen CIA in an IDO-dependent manner. Thus, the potential therapeutic effects of iTregs in CIA are likely maintained through the generation of tolerogenic DCsin vivo.

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Serum Testosterone to Androstenedione Ratio Predicts Metabolic Health in Normal-Weight Polycystic Ovary Syndrome Women

Journal of the Endocrine Society ◽

10.1210/jendso/bvab158 ◽

2021 ◽

Author(s):

Daniel A Dumesic ◽

Ayli Tulberg ◽

Megan McNamara ◽

Tristan R Grogan ◽

David H Abbott ◽

...

Keyword(s):

Insulin Resistance ◽

Polycystic Ovary Syndrome ◽

Polycystic Ovary ◽

Elevated Serum ◽

Normal Weight ◽

Model Assessment ◽

Metabolic Function ◽

Ovary Syndrome ◽

Intravenous Glucose

Abstract Context Increased aldo-keto reductase 1C3 (AKR1C3)-mediated conversion of androstenedione (A4) to testosterone (T) promotes lipid storage in subcutaneous (SC) abdominal adipose in overweight/obese polycystic ovary syndrome (PCOS) women. Objective To examine whether an elevated serum T/A4 ratio, as a marker of enhanced AKR1C3 activity in SC abdominal adipose, predicts metabolic function in normal-weight PCOS women. Design Prospective cohort study. Setting Academic center. Patients Nineteen normal-weight PCOS women; 21 age- and body mass index-matched controls. Intervention(s) Circulating hormone/metabolic determinations, intravenous glucose tolerance testing, total body dual-energy x-ray absorptiometry, SC abdominal fat biopsy. Main Outcome Measure(s) Serum T/A4 ratios, hormone/metabolic measures and AKR1C3 expression of adipocytes matured in vitro were compared between female types; serum T/A4 ratios were correlated with serum lipids, adipose insulin resistance (adipose-IR), homeostatic model assessment of insulin resistance (HOMA-IR) and insulin sensitivity (Si). Results Increased serum T/A4 ratios (P=0.040) and log adipose-IR values (P=0.002) in PCOS women versus controls were accompanied by AKR1C3 mRNA overexpression of PCOS adipocytes matured in vitro (P=0.016). Serum T/A4 ratios in PCOS women, but not controls, negatively correlated with log triglycerides (TG: R=-0.65, P=0.002) and the TG index (R=-0.57, P=0.011). Adjusting for serum free T, serum T/A4 ratios in PCOS women remained negatively correlated with log TG (R=-0.57, P=0.013) and TG index (R=-0.50, P=0.036), respectively, without significant relationships with other metabolic measures. Conclusion An elevated serum T/A4 ratio, as a marker of enhanced AKR1C3 activity in SC abdominal adipose, predicts healthy metabolic function in normal-weight PCOS women.

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Ascidian Tunicate Extracts Attenuate Rheumatoid Arthritis in a Collagen-induced Murine Model

Natural Product Communications ◽

10.1177/1934578x1400900632 ◽

2014 ◽

Vol 9 (6) ◽

pp. 1934578X1400900

Author(s):

Seong-Ho Hong ◽

Jung-Taek Kwon ◽

Jae-Ho Lee ◽

Somin Lee ◽

Ah Young Lee ◽

...

Keyword(s):

Rheumatoid Arthritis ◽

Interleukin 10 ◽

Treated Group ◽

Pcr Analysis ◽

Prostaglandin E ◽

Therapeutic Effects ◽

Paw Edema ◽

Mice Model ◽

The Matrix ◽

Inflammatory Proteins

Murine rheumatoid arthritis models are often used to investigate the potential therapeutic effects of candidate drugs. The present study has been conducted in order to investigate the therapeutic efficacy of ascidian tunicate extracts in a collagen-induced arthritis DBA1/J mice model. Four types of formulas, ascidian tunicate extracts (ATE), crude ascidian tunicate glycans (ATEC), ascidian tunicate extracts with licorice extracts (ATEL), and crude ascidian tunicate glycans with licorice extracts (ATECL) were orally administered into DBA/1J mice for 3 weeks and paw edema and thickness were evaluated. Changes in inflammatory proteins and cytokines levels were monitored in hind leg tissues by Western blot and quantitative PCR analysis. The oral administration of ascidian tunicate extracts alleviated paw edema and improved the histological hind leg cartilage status. The extracts also reduced the matrix metalloproteinase-9 (MMP-9) protein and prostaglandin E synthase (PGES) levels. In addition, the extracts-treated groups showed increased interleukin-10 (IL-10) levels compared with the non-treated group. These findings suggest that orally administered ascidian tunicate extracts might have potential therapeutic effects for the treatment of rheumatoid arthritis.

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Immunomodulatory Effects of Adipose Tissue-Derived Stem Cells on Concanavalin A-Induced Acute Liver Injury in Mice

Cell Medicine ◽

10.3727/215517916x693159 ◽

2017 ◽

Vol 9 (1-2) ◽

pp. 21-33 ◽

Cited By ~ 10

Author(s):

Yasuma Yoshizumi ◽

Hiroshi Yukawa ◽

Ryoji Iwaki ◽

Sanae Fujinaka ◽

Ayano Kanou ◽

...

Keyword(s):

Stem Cells ◽

Adipose Tissue ◽

Mouse Model ◽

Cell Therapy ◽

Concanavalin A ◽

Therapeutic Effects ◽

Dependent Manner ◽

Immunomodulatory Effects

Cell therapy with adipose tissue-derived stem cells (ASCs) is expected to be a candidate for the treatment of fulminant hepatic failure (FHF), which is caused by excessive immune responses. In order to evaluate the therapeutic effects of ASCs on FHF, the in vitro and in vivo immunomodulatory effects of ASCs were examined in detail in the mouse model. The in vitro effects of ASCs were examined by assessing their influence on the proliferation of lymphomononuclear cells (LMCs) stimulated with three kinds of mitogens: phorbol 12-myristate 13-acetate (PMA) plus ionomycin, concanavalin A (ConA), and lipopolysaccharide (LPS). The proliferation of LMCs was efficiently suppressed in a dose-dependent manner by ASCs in the cases of PMA plus ionomycin stimulation and ConA stimulation, but not in the case of LPS stimulation. The in vivo effects of transplanted ASCs were examined in the murine FHF model induced by ConA administration. The ALT levels and histological inflammatory changes in the ConA-administered mice were apparently relieved by the transplantation of ASCs. The analysis of mRNA expression patterns in the livers indicated that the expressions of the cytokines such as Il-6, Il-10, Ifn-γ, and Tnf-α, and the cell surface markers such as Cd3γ, Cd4, Cd8α, Cd11b, and Cd11c were downregulated in the ASC-transplanted mice. The immunomodulatory and therapeutic effects of ASCs were confirmed in the mouse model both in vitro and in vivo. These suggest that the cell therapy with ASCs is beneficial for the treatment of FHF.

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Agriophyllum Oligosaccharides Ameliorate Diabetic Insulin Resistance Through INS-R/IRS/Glut4-Mediated Insulin Pathway in db/db Mice and MIN6 Cells

Frontiers in Pharmacology ◽

10.3389/fphar.2021.656220 ◽

2021 ◽

Vol 12 ◽

Author(s):

Shuyin Bao ◽

Xiuzhi Wang ◽

Sung Bo Cho ◽

Yan-Ling Wu ◽

Chengxi Wei ◽

...

Keyword(s):

Insulin Resistance ◽

Insulin Receptor ◽

Treated Group ◽

Control Group ◽

Spectrometric Analysis ◽

Precolumn Derivatization ◽

Mrna Levels ◽

Insulin Pathway ◽

Min6 Cells

We have previously reported that Agriophyllum oligosaccharides (AOS) significantly enhance glycemic control by increasing the activation of insulin receptor (INS-R), insulin receptor substrate-2 (IRS-2), phosphatidylinositol 3 kinase (PI3K), protein kinase B (AKT), peroxisome proliferator-activated receptor (PPAR)-γ, and glucose transporter 4 (Glut4) proteins in hepatic tissues. However, the effect of glucose control by AOS on the regulation of pancreatic tissues in db/db mice and MIN6 cells remains to be determined. An oral dose of AOS (380 or 750 mg/kg) was administered to type-2 diabetic db/db mice for 8 weeks to determine whether AOS regulates glucose by the INS-R/IRS/Glut4-mediated insulin pathway. Meanwhile, the effects of AOS on glucose uptake and its related signaling pathway in MIN6 cells were also investigated. The results showed that the random blood glucose (RBG) level in the AOS-treated group was lower than that in the control group. AOS reduced the levels of glycated hemoglobin (HbA1c) and free fatty acid (FFA) and significantly improved the pathological changes in the pancreatic tissues in db/db mice. Moreover, immunohistochemical analysis revealed that the expression of INS-R, IRS-1, IRS-2, and Glut4 was increased in the AOS-treated group than in the model group. Further, in vitro experiments using MIN6 cells showed that AOS regulated INS-R, IRS-1, IRS-2, and Glut4 protein and mRNA levels and attenuated insulin resistance and cell apoptosis. The results of both in vitro and in vivo experiments were comparable. Ultra-performance liquid chromatography coupled with time-of-flight mass spectrometric analysis of AOS with precolumn derivatization with 3-amino-9-ethylcarbazole (AEC) tentatively identified five types of sugars: glucose, lactose, rutinose, glucuronic acid, and maltotriose. Our present study clearly showed that AOS is efficacious in preventing hyperglycemia, possibly by increasing insulin sensitivity and improving IR by regulating the INS-R/IRS/Glut4 insulin signal pathway. Therefore, AOS may be considered as a potential drug for diabetes treatment.

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Therapeutic effects of iNOS inhibition against vitiligo in an animal model

European Journal of Translational Myology ◽

10.4081/ejtm.2019.8383 ◽

2019 ◽

Vol 29 (3) ◽

Author(s):

Hamid Mansourpour ◽

Katayoun Ziari ◽

Sahar Kalantar Motamedi ◽

Amin Hassan Poor

Keyword(s):

Nitric Oxide ◽

Nitric Oxide Synthase ◽

Mouse Model ◽

Therapeutic Effects ◽

Mice Model ◽

Inos Inhibitor ◽

Constitutive Nitric Oxide Synthase ◽

Oxide Synthase ◽

Inos Inhibition ◽

Inducible Nitric Oxide

Nitric oxide (NO) is involved in several biological processes, but its role in human melanogenesis and vitiligo need further studies. Previous studies revealed that exposure to UVA and UVB were capable of the inducing nitric oxide production in keratinocytes and melanocytes through the activation of constitutive nitric oxide synthase, whereas inducible nitric oxide synthase overexpression has been reported to play an important role in hyperpigmentary disorders. The aim of this study was to evaluate iNOS inhibitor aminoguanidine (AG) as a therapeutic agent in our mouse model of vitiligo. In this study, male C57BL/6J Ler-vit/vit mice were purchased to evaluate the effect of iNOS inhibitor (aminoguanidine) (50 and 100 mg/kg) and L-arginine (100 mg/kg) in a mouse model of vitiligo induced by monobenzone 40%. Moreover, we used phototherapy device to treat the mice with NBUVB as a gold standard.The findings revealed that monobenzone was capable of inducing depigmentation after 6 weeks. However, aminoguanidine in combination with monobenzone was decrease the effect of monobenzone, while L-arginine play a key role in promoting the effect of monobenzone (P<0.001). Based on the phototherapy, the efficacy of phototherapy significantly increased by adding L-arginine (P<0.05). Taken together, we suggest that iNOS inhibitor can be a novel treatment for the prevention and treatment of vitiligo by combination of NBUVB therapy, furthermore; NO agents like L-arginine could also increase the effectiveness of phototherapy. Taken together, this pilot study showed significant repigmentation of vitiligous lesions treated with iNOS inhibitor plus NBUVB therapy, where other aspect including expression of an inducible iNOS, NO and TNF levels remained to be evaluated in mice model.

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Adenosine A2A Receptor Agonist Mediated Prevention of Graft-Versus Host Disease In the Mouse Is Associated with An Increase of T-Regulatory Cells In Target Organs.

Blood ◽

10.1182/blood.v116.21.3744.3744 ◽

2010 ◽

Vol 116 (21) ◽

pp. 3744-3744

Author(s):

Kyu Lee Han ◽

Sherry Walker ◽

Harry L. Malech ◽

Elizabeth M. Kang

Keyword(s):

T Cells ◽

Mouse Model ◽

Acute Gvhd ◽

T Regulatory Cells ◽

Treated Group ◽

Regulatory Cells ◽

High Power Field ◽

Target Organs ◽

A2ar Agonist

Abstract Abstract 3744 Graft versus host disease (GVHD) is a serious complication of allogenic hematopoietic stem cell transplantation (HSCT) affecting primarily the liver, intestine, skin and lymphoid organs. T-regulatory cells (Tregs) are a subset of T cells that are characterized by CD4+CD25high and express the Foxp3 transcription factor. There is increasing recognition that Tregs likely are important in preventing development, reducing the severity and/or mediating resolution of GVHD. It has been reported that giving donor Tregs will suppress development of GVHD in a mouse model; however it is not clear whether the immunologic suppression by Tregs occurs in the target organs. Agonists of the Gs-coupled Adenosine A2A receptor (A2AR) agonists have been demonstrated to terminate inflammation and improve survival in solid organ transplant ischemia models. We previously have reported that the A2AR specific agonist, ATL146e, also can decrease the incidence and severity of GVHD as well as improve survival of mice in a GVHD transplant mouse model. In this same GVHD mouse model, ATL146e treatment increases the number of donor derived CD4+CD25highFoxp3+ Tregs. In order to further understand the role of the agonist in GVHD abrogation we performed studies looking at A2AR agonist mediated appearance of Tregs in the target organs affected by GVHD in this model. Using a parental into irradiated F1 offspring transplant model (C57BL/6J [B6, H-2b] -> B6D2F1/J [BDF1, H-2b/d]) we can induce GVHD as manifested by weight loss and mortality in 100% of mice by infusing an additional 10 million donor T cells into mice previously engrafted with 10 million bone marrow donor cells using 850cGy conditioning. We administered the A2AR specific agonists, ATL1223 or ATL370, or a PBS control by osmotic mini pumps resulting in continuous subcutaneous infusion for 14 days starting one day before the donor T cell infusion. Mice that received only the donor bone marrow transplant and not the additional donor T cells did not develop GVHD and served as an additional control. We collected ear and colon biopsies from the transplanted mice to assess these target organs (skin and gut) usually affected by GVHD in this model. Tissue was obtained, placed in 10% formalin and paraffin embedded and stained by immunohistochemistry (IHC) for intracellular FoxP3 by incubating overnight with 1:200 mouse anti-mouse/human/rat—FoxP3 IgG. The slides were washed and then incubated with anti-mouse IgG conjugated to Tetramethylrhodamine (TRITC). We then counted the number of Foxp3+ cells per high power field. We also examined whether specific agonist activation of A2AR can increase the number of Tregs in vitro by culturing CD4+ CD25− cells in the presence of either TGF-beta and/or the A2AR specific agonists. As in our previous studies with the specific A2AR agonist ATL146e, the agonists ATL1223 and ATL370 also were effective at preventing the acute GVHD syndrome of weight loss and mortality seen in the PBS treated controls. Treatment with these agonists resulted in an increase in CD4+CD25+FoxP3+ Tregs in the spleen compared to the PBS treated group at days 14 to 20 after HSCT. In addition we were able to document significant increases in the number of Foxp3 positive T lymphocytes infiltrating skin and colon compared to the PBS treated group. The number of Foxp3+ T cells per high power field was 14 ± 6 in the control and 64 ± 14 in the A2AR agonist treated mice (p = 0.0281). Finally from our in vitro data we also observed a 4.2 to 5.4 fold increase in the number of Foxp3+ Tregs in vitro after A2AR activation compared to TGF beta treatment only. Thus we have confirmed that the specific activation of A2AR inhibits acute GVHD through the increase of donor-derived CD4+ CD25+ FoxP3+ immunosuppressive T regulatory cells in vivo and in vitro. Furthermore, our histological observation suggests the possibility that increased Tregs by treatment with A2AR specific agonist is responsible for suppressing the immune response in GVHD target tissues. Therefore, our observation provides additional mechanistic basis for the anti-inflammatory capacity of A2AR agonist in acute GVHD. Additional studies are ongoing to further elucidate the mechanism by which A2AR specific agonist increases Tregs. Disclosures: No relevant conflicts of interest to declare.

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Lactobacillus rhamnosus attenuates bone loss and maintains bone health by skewing Treg-Th17 cell balance in Ovx mice

Scientific Reports ◽

10.1038/s41598-020-80536-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Leena Sapra ◽

Hamid Y. Dar ◽

Asha Bhardwaj ◽

Amit Pandey ◽

Surbhi Kumari ◽

...

Keyword(s):

Bone Loss ◽

Bone Health ◽

Th17 Cells ◽

Lactobacillus Rhamnosus ◽

Treated Group ◽

Mice Model ◽

First Time ◽

Immunomodulatory Potential

AbstractOsteoporosis is a systemic-skeletal disorder characterized by enhanced fragility of bones leading to increased rates of fractures and morbidity in large number of populations. Probiotics are known to be involved in management of various-inflammatory diseases including osteoporosis. But no study till date had delineated the immunomodulatory potential of Lactobacillus rhamnosus (LR) in bone-health. In the present study, we examined the effect of probiotic-LR on bone-health in ovariectomy (Ovx) induced postmenopausal mice model. In the present study, we for the first time report that LR inhibits osteoclastogenesis and modulates differentiation of Treg-Th17 cells under in vitro conditions. We further observed that LR attenuates bone loss under in vivo conditions in Ovx mice. Both the cortical and trabecular bone-content of Ovx+LR treated group was significantly higher than Ovx-group. Remarkably, the percentage of osteoclastogenic CD4+Rorγt+Th17 cells at distinct immunological sites such as BM, spleen, LN and PP were significantly reduced, whereas the percentage of anti-osteoclastogenic CD4+Foxp3+Tregs and CD8+Foxp3+Tregs were significantly enhanced in LR-treated group thereby resulting in inhibition of bone loss. The osteoprotective role of LR was further supported by serum cytokine data with a significant reduction in osteoclastogenic cytokines (IL-6, IL-17 and TNF-α) along with enhancement in anti-osteoclastogenic cytokines (IL-4, IL-10, IFN-γ) in LR treated-group. Altogether, the present study for the first time establishes the osteoprotective role of LR on bone health, thus highlighting the immunomodulatory potential of LR in the treatment and management of various bone related diseases including osteoporosis.

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Metformin protects against insulin resistance induced by high uric acid in cardiomyocytes via AMPK signaling pathways in vitro and in vivo

10.21203/rs.3.rs-300030/v1 ◽

2021 ◽

Author(s):

Zhenyu Jiao ◽

Yingqun Chen ◽

Yang Xie ◽

Yanbing Li ◽

Zhi Li

Keyword(s):

Insulin Resistance ◽

Uric Acid ◽

Glucose Metabolism ◽

Glucose Tolerance ◽

Mouse Model ◽

Glucose Uptake ◽

Glucose Transporter ◽

Abnormal Glucose Metabolism ◽

Insulin Tolerance

Abstract BackgroundHigh uric acid (HUA) is associated with insulin resistance and abnormal glucose metabolism in cardiomyocytes. Metformin is a recognized agonist of AMP-activated protein kinase (AMPK) and an antidiabetic drug widely used for type 2 diabetes. It can play a cardioprotective role in many pathways. We investigated whether metformin protects against HUA-induced insulin resistance and abnormal glucose metabolism in cardiomyocytes.MethodsWe exposed primary cardiomyocytes to HUA, and cellular glucose uptake was quantified by measuring the uptake of 2-NBDG, a fluorescent glucose analog, after insulin excitation.ResultsTreatment with metformin (10 µmol/L) protected against HUA-inhibited glucose uptake induced by insulin in primary cardiomyocytes, as shown by fluorescence microscopy and flow cytometry analysis. HUA directly inhibited the phosphorylation of Akt and the translocation of glucose transporter type 4 (GLUT4) induced by insulin, which was blocked by metformin. Metformin promoted phosphorylation of AMPK, renewed HUA-inhibited glucose uptake induced by insulin and protected against insulin resistance in cardiomyocytes. As a result of these effects, in a mouse model of acute hyperuricemia, metformin improved insulin tolerance and glucose tolerance, accompanied by increased AMPK phosphorylation, Akt phosphorylation and translocation of GLUT4 in myocardial tissues. As expected, AICAR, another AMPK activator, had equivalent effects to metformin, demonstrating the important role of AMPK activation in protecting against insulin resistance induced by HUA in cardiomyocytes. Metformin protects against insulin resistance induced by HUA in cardiomyocytes and improves insulin tolerance and glucose tolerance in an acute hyperuricemic mouse model, along with the activation of AMPK.ConclusionsConsequently, metformin may be an important potential new treatment strategy for hyperuricemia-related cardiovascular disease.

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