Antidiabetic drug administration prevents bone mineral density loss: Evidence from a two-sample Mendelian randomization study.

The aim of this study was to investigate the effect of common antidiabetic drugs on BMD by two-sample Mendelian randomization (MR). The single nucleotide polymorphisms that were strongly associated with insulin, metformin, rosiglitazone and gliclazide were extracted as instrumental variables (IVs) for MR analysis. The inverse variance weighted (IVW) method was used as the primary MR method to assess the causal effect of antidiabetic drugs on BMD, and other MR methods, including Weighted median, MR Egger and Weighted mode, were used for complementary analysis. Reliability and stability were assessed by the leave-one-out test. In the present work, IVW estimation of the causal effect of insulin on heel BMD demonstrated that there was a null effect of insulin on heel BMD (ß = 0.765; se = 0.971; P = 0.430), while metformin treatment had a positive effect on heel BMD (ß = 1.414; se = 0.460; P = 2.118*10-3). The causal relationship between rosiglitazone and heel BMD analysed by IVW suggested that there was a null effect of rosiglitazone on heel BMD (ß = -0.526; se = 1.744; P = 0.763), but the causal effect of gliclazide on heel BMD evaluated by IVW demonstrated that there was a positive effect of gliclazide on heel BMD (ß = 2.671; se = 1.340; P = 0.046). In summary, the present work showed that metformin and gliclazide have a role in reducing BMD loss in patients with diabetes and are recommended for BMD loss prevention in diabetes.

Abrus precatorius Leaf Extract Stimulates Insulin-mediated Muscle Glucose Uptake: In vitro Studies and Phytochemical Analysis.

Diabetes mellitus, linked with insulin resistance and hyperglycaemia, is a leading cause of mortality. Glucose uptake through glucose transporter type 4, especially in skeletal muscle, is crucial for maintaining euglycaemia and is a key pathway targeted by antidiabetic medication. Abrus precatorius is a medicinal plant with demonstrated antihyperglycaemic activity in animal models, but its mechanisms are unclear.This study evaluated the effect of a 50% ethanolic (v/v) A. precatorius leaf extract on (1) insulin-stimulated glucose uptake and (2) related gene expression in differentiated C2C12 myotubes using rosiglitazone as a positive control, and (3) generated a comprehensive phytochemical profile of A. precatorius leaf extract using liquid chromatography-high resolution mass spectrometry to elucidate its antidiabetic compounds. A. precatorius leaf extract significantly increased insulin-stimulated glucose uptake, and insulin receptor substrate 1 and Akt substrate of 160 kDa gene expression; however, it had no effect on glucose transporter type 4 gene expression. At 250 µg/mL A. precatorius leaf extract, the increase in glucose uptake was significantly higher than 1 µM rosiglitazone. Fifty-five phytochemicals (primarily polyphenols, triterpenoids, saponins, and alkaloids) were putatively identified, including 24 that have not previously been reported from A. precatorius leaves. Abrusin, precatorin I, glycyrrhizin, hemiphloin, isohemiphloin, hispidulin 4'-O-ß-D-glucopyranoside, homoplantaginin, and cirsimaritin were putatively identified as known major compounds previously reported from A. precatorius leaf extract. A. precatorius leaves contain antidiabetic phytochemicals and enhance insulin-stimulated glucose uptake in myotubes via the protein kinase B/phosphoinositide 3-kinase pathway by regulating insulin receptor substrate 1 and Akt substrate of 160 kDa gene expression. Therefore, A. precatorius leaves may improve skeletal muscle insulin sensitivity and hyperglycaemia. Additionally, it is a valuable source of bioactive phytochemicals with potential therapeutic use for diabetes.

The effects of pioglitazone and rosiglitazone on liver function in hypothyroid rats.

OBJECTIVES: This study aimed to investigate the antioxidant effect of rosiglitazone (ROG) and pioglitazone (POG) on oxidative damage and dysfunction of hepatic tissue in hypothyroid rats. METHODS: The male rats were classified into six groups: (1) Control; (2) Hypothyroid, (3) Hypothyroid-POG 10, (4) Hypothyroid-POG 20, (5) Hypothyroid-ROG 2, and (6) Hypothyroid-ROG 4. To induction hypothyroidism in rats, propylthiouracil (PTU) (0.05 %w/v) was added to drinking water. In groups 2-6, besides PTU, the rats were also intraperitoneal administrated with 10 or 20 mg/kg POG or 2 or 4 mg/kg ROG for six weeks. Finally, after deep anesthesia, the blood was collected to measure the serum biochemical markers and hepatic tissue was separated for biochemical oxidative stress markers. RESULTS: Administration of PTU significantly reduced serum thyroxin concentration, total thiol levels, activity of superoxide dismutase (SOD) and catalase (CAT) enzymes, and increased serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (Alk-P) and malondialdehyde (MDA) in the liver. Additionally, our results showed that prescription of POG or ROG for six weeks to hypothyroid rats resulted in an improvement in liver dysfunction (decrease in serum levels of AST, ALT, and ALK-P) through reducing oxidative damage in hepatic tissue (increase in CAT, SOD, or total thiols and decrease in MDA levels). CONCLUSIONS: The findings of the present study presented that the IP administration of POG and ROG for six weeks improves liver dysfunction induced by hypothyroidism in juvenile rats by reducing oxidative damage.

Thiazolidinedione enhances the efficacy of anti-PD-1 monoclonal antibody in murine melanoma.

Several clinical studies observed a surprising beneficial effect of obesity on enhancing immunotherapy responsiveness in patients with melanoma, highlighting an as-yet insufficiently understood relationship between metabolism and immunogenicity. Here, we demonstrate that the thiazolidinedione (TZD) rosiglitazone, a drug commonly used to treat diabetes by sequestering fatty acids in metabolically inert subcutaneous adipose tissue, improved sensitivity to anti-programmed cell death protein 1 (PD-1) treatment in YUMMER1.7 tumor-bearing mice, an initially immunotherapy-sensitive murine melanoma model. We observed a transition from high to intermediate PD-1 expression in tumor-infiltrating CD8+ T cells. Moreover, TZD inhibited PD-1 expression in mouse and human T cells treated in vitro. In addition to its direct impact on immune cells, TZD also decreased circulating insulin concentrations, while insulin induced T cell exhaustion in culture. In TZD-treated mice, we observed higher fatty acid concentrations in the tumor microenvironment, with fatty acids protecting against exhaustion in culture. Together, these data are consistent with an indirect mechanism of TZD inhibiting T cell exhaustion. Finally, we analyzed imaging data from patients with melanoma before and after anti-PD-1 treatment, confirming the beneficial effect of increased subcutaneous fat on anti-PD-1 responsiveness in patients. We also found that the expression of peroxisome proliferator-activated receptor gamma (PPARγ), the canonical activator of lipid uptake and adipogenesis activated by TZD, correlated with overall survival time. Taken together, these data identify a new adjuvant to enhance immunotherapy efficacy in YUMMER1.7 melanoma mice, and discover a new metabolism-based prognostic marker in human melanoma.NEW & NOTEWORTHY Zhang et al. demonstrate that the diabetes drug rosiglitazone improves the efficacy of immunotherapy in mouse melanoma. This effect is both direct and indirect: TZD directly reduces PD-1 expression in CD8+ T cells (i.e., reduces exhaustion), and indirectly reduces exhaustion by lowering insulin levels and increasing local fat. Finally, they demonstrate that hallmarks of TZD action (such as PPARγ expression and subcutaneous fat content) correlate with improved immunotherapy efficacy in humans with melanoma.

Essential oil from Fructus Alpiniae zerumbet ameliorates vascular endothelial cell senescence in diabetes by regulating PPAR-γ signalling: A 4D label-free quantitative proteomics and network pharmacology study.

ETHNOPHARMACOLOGICAL RELEVANCE: Vascular endothelial cell senescence is associated with cardiovascular complications in diabetes. Essential oil from Fructus Alpiniae zerumbet (Pers.) B.L.Burtt & R.M.Sm. (EOFAZ) has potentially beneficial and promising diabetes-related vascular endothelial cell senescence-mitigating effects; however, the underlying molecular mechanisms remain unclear. AIM OF THE STUDY: To investigate the molecular effects of EOFAZ on vascular endothelial cell senescence in diabetes. MATERIALS AND METHODS: A diabetes mouse model was developed using a high-fat and high-glucose diet (HFD) combined with intraperitoneal injection of low-dose streptozotocin (STZ, 30 mg/kg) and oral treatment with EOFAZ. 4D label-free quantitative proteomics, network pharmacology, and molecular docking techniques were employed to explore the molecular mechanisms via which EOFAZ alleviates diabetes-related vascular endothelial cell senescence. A human aortic endothelial cells (HAECs) senescence model was developed using high palmitic acid and high glucose (PA/HG) concentrations in vitro. Western blotting, immunofluorescence, SA-ß-galactosidase staining, cell cycle, reactive oxygen species (ROS), cell migration, and enzyme linked immunosorbent assays were performed to determine the protective role of EOFAZ against vascular endothelial cell senescence in diabetes. Moreover, the PPAR-γ agonist rosiglitazone, inhibitor GW9662, and siRNA were used to verify the underlying mechanism by which EOFAZ combats vascular endothelial cell senescence in diabetes. RESULTS: EOFAZ treatment ameliorated abnormal lipid metabolism, vascular histopathological damage, and vascular endothelial aging in diabetic mice. Proteomics and network pharmacology analysis revealed that the differentially expressed proteins (DEPs) and drug-disease targets were associated with the peroxisome proliferator-activated receptor gamma (PPAR-γ) signalling pathway, a key player in vascular endothelial cell senescence. Molecular docking indicated that the small-molecule compounds in EOFAZ had a high affinity for the PPAR-γ protein. Western blotting and immunofluorescence analyses confirmed the significance of DEPs and the involvement of the PPAR-γ signalling pathway. In vitro, EOFAZ and rosiglitazone treatment reversed the effects of PA/HG on the number of senescent endothelial cells, expression of senescence-related proteins, the proportion of cells in the G0/G1 phase, ROS levels, cell migration rate, and expression of pro-inflammatory factors. The protective effects of EOFAZ against vascular endothelial cell senescence in diabetes were aborted following treatment with GW9662 or PPAR-γ siRNA. CONCLUSIONS: EOFAZ ameliorates vascular endothelial cell senescence in diabetes by activating PPAR-γ signalling. The results of the present study highlight the potential beneficial and promising therapeutic effects of EOFAZ and provide a basis for its clinical application in diabetes-related vascular endothelial cell senescence.

Effects of Moringa Oleifera Leaf Extract Plus Rosiglitazone on Serum Leptin and Glucose and Lipid Metabolism in Type 2 Diabetic Rats.

Objective: To investigate the effects of Moringa Oleifera Leaf Extract (MOLE) plus rosiglitazone (RSG) on glucose and lipid metabolism, serum leptin, and the Akt/GSK3ß/ß-Catenin signaling pathway in type 2 diabetic (T2D) rats. Methods: Sixty male Sprague-Dawley (SD) rats were randomly divided into six groups: the normal group, the model group, the RSG group, the low- and high-dose MOLE group, and the MOLE+RSG group. The normal group was fed a standard rat diet, while the other groups were given a single intraperitoneal injection of low-dose streptozomycin (STZ) (35 mg/kg) and fed a high-sugar and high-fat diet. After 8 weeks, the treatment outcomes were evaluated by measuring key parameters of blood glucose and lipid metabolism and the protein kinase B (AKT) / Glycogen synthase kinase 3beta (GSK3ß) /ß-Catenin signaling pathway in the T2D rats. Results: Compared with the normal group, the model group showed significantly increased levels of blood glucose, blood lipids, serum leptin, free fatty acid (FFA), and tumor necrosis factor-α (TNF-α). Compared with the model group, the RSG, low-dose MOLE, and high-dose MOLE groups displayed effective control of blood glucose, blood lipids, serum leptin, FFA, and TNF-α. The MOLE+RSG group surpassed the RSG group in regulating glucose, lipid metabolism, and serum leptin levels in T2D rats. In addition, the MOLE+RSG group also had superiority over the RSG group in activating the AKT/GSK3ß/ß-Catenin pathway. Conclusion: MOLE plus RSG can effectively reduce blood glucose and blood lipids in T2DM rats.

Juniper Berries Regulate Diabetes and Obesity Markers Through Modulating PPARα, PPARγ, and LXR: In Vitro and In Vivo Effects.

The berries of Juniperus communis have been traditionally used for therapeutic purposes. They have been reported to possess various pharmacological effects such as anti-inflammatory, hypoglycemic and hypolipidemic activities. In this study, a methanolic extract of J. communis berries (JB) was evaluated for its effects on peroxisome proliferator-activated receptors alpha and gamma (PPARα and PPARγ), liver X receptor (LXR), glucose uptake and lipid accumulation using various cellular systems. At a concentration of 25 µg/mL, JB caused 3.77-fold activation of PPARα, 10.90-fold activation of PPARγ, and 4.43-fold activation of LXR in hepatic cells. JB inhibited (11%) the adipogenic effect induced by rosiglitazone in adipocytes and increased glucose uptake (90%) in muscle cells. In high-fat diet (HFD) fed mice, JB at a dose of 25 mg/kg body weight exhibited a 21% decrease in body weight. Fasting glucose levels in mice treated with 12.5 mg/kg of JB were significantly decreased (39%) indicating its efficacy in regulating hyperglycemia and obesity induced by HFD thus ameliorating the symptoms of type 2 diabetes. A series of energy metabolic genes, including Sirt1 (2.00-fold) and RAF1 (2.04-fold), were upregulated by JB, while rosiglitazone regulated the hepatic PPARγ only. Phytochemical analysis of JB indicated presence of a number of flavonoids and biflavonoids which seem to be responsible for the observed activity. It was concluded that JB acted as a multiple agonist of PPARα, PPARγ and LXR without the undesired effect of adipogenesis and exhibited the property of enhancing glucose uptake. The regulation of PPARα, PPARγ and LXR seems to be through Sirt1 and RAF1. In vivo results confirmed the antidiabetic and antiobesity potential of JB and indicated its utility in metabolic disorder and type 2 diabetes.

Danshao Shugan Granule therapy for non-alcoholic fatty liver disease.

BACKGROUND: Danshao Shugan Granules (DSSG), a traditional Chinese medicine (TCM), is given to protect the liver. The objective is to evaluate the mechanisms of the effects of DSSG on non-alcoholic fatty liver disease (NAFLD). METHODS: 260 patients with NAFLD were randomly allocated to positive control drugs rosiglitazone (n = 30) and Silibinin (n = 50) as well as DSSG (n = 130) and combined DSSG/Silibinin (n = 50) groups, from which 90 patients in the DSSG group were further subdivided into 3 groups (n = 30, each) depending on the severity of symptoms. In total 33 Sprague-Dawley rats were assigned to normal (n = 10) or 45% high-fat diet (n = 23) groups, from which 9 rats served as negative controls, 10 as model controls and 10 were treated with DSSG. RESULTS: DSSG medications had significantly highest effects on B-ultrasonography finding improvements, and reductions of total cholesterol, triglyceride, aspartate transaminase and γ-glutamyl transpeptidase in NAFLD patients. Silibinin application only led to significantly highest alanine transaminase reductions and rosiglitazone medication to significantly highest fasting plasma glucose reductions. In a murine in vivo NAFLD model glucose (GLU), total cholesterol (TC) triacylglycerol (TG) as well as glutamic pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT) and gamma-glutamyl transferase (GGT) serum concentrations were all significantly reduced (P < 0.001) and the expression of nuclear factor-κB (NF­κB) was significantly decreased in DSSG treated compared to untreated NAFLD animals (P < 0.001). In addition, the DSSG treated rats exhibited increased superoxide dismutase activity and reduced malondialdehyde values. CONCLUSIONS: DSSG was effective for treating NAFLD patients, which could be attributed to increased activity of superoxide dismutase, a decrease of malondialdehyde as well as reduced NF­κB activity in a NAFLD rat model.

Focal Microscopy Observe the Mechanism of Gegen Qinlian Decoction Treating Type 2 Diabetic Nephropathy in Nude Mice.

The incidence of diabetes is increasing year by year; among them, the rising trend of T2D is particularly obvious, and because it has many complications and poor prognosis, it has become one of the diseases that seriously endanger human health. Gegen Qinlian Decoction (GQD) has achieved good results in the treatment of type 2 diabetes (T2D). It can not only improve the anti-insulin effect of nude mice with type 2 diabetic, but also has the characteristics of small side effects and remarkable curative effect; it can improve the function of tissues and organs by multiple target spots and multiple ways. The method was to raise 30 nude mice with high fat and high sugar and inject small doses of streptozotocin (STZ). The treated nude mice were randomly divided into rosiglitazone group, Gegen Qinlian group, and model group, normally rearing 10 nude mice as a control group. The model group and the blank group were treated with 0.9% sodium chloride solution at 10 mL/kg, and the rosiglitazone group was intragastric administration with 3 mg/kg rosiglitazone solution. The GQD group was treated with 18.2 g/kg GQD, once a day, and lasting for 4 weeks. Use blood glucose meter to detect the FBG content in nude mice, use the radioimmunoassay to detect the amount of FINS, and calculate HOMA-IR. Use immunoenzyme linked assay method to detect the level of serum inflammatory factors. The experimental results showed that compared with the model group, the FBG of the rosiglitazone group mice was significantly decreased; the levels of the rosiglitazone group and the Gegen Qinlian group were significantly lower. Therefore, it is concluded that GQD can treat T2D in nude mice.

Effects of ginkgo leaf tablet on the pharmacokinetics of rosiglitazone in rats and its potential mechanism.

CONTEXT: Ginkgo leaf tablet (GLT), a traditional Chinese herbal formula, is often combined with rosiglitazone (ROS) for type 2 diabetes mellitus treatment. However, the drug-drug interaction between GLT and ROS remains unknown. OBJECTIVE: To investigate the effects of GLT on the pharmacokinetics of ROS and its potential mechanism. MATERIALS AND METHODS: The pharmacokinetics of 10 mg/kg ROS with 100/200 mg/kg GLT as single-dose and 10-day multiple-dose administration were investigated in Sprague-Dawley rats. In vitro, the effects of GLT on the activity of CYP2C8 and CYP2C9 were determined in recombinant human yeast microsomes and rat liver microsomes with probe substrates. RESULTS: The t1/2 of ROS increased from 2.14 ± 0.38 (control) to 2.79 ± 0.37 (100 mg/kg) and 3.26 ± 1.08 h (200 mg/kg) in the single-dose GLT administration. The AUC0-t (139.69 ± 45.46 vs. 84.58 ± 39.87 vs. 66.60 ± 15.90 h·µg/mL) and t1/2 (2.75 ± 0.70 vs. 1.99 ± 0.44 vs. 1.68 ± 0.35 h) decreased significantly after multiple-dose GLT treatment. The IC50 values of quercetin, kaempferol, and isorhamnetin, GLT main constituents, were 9.32, 7.67, and 11.90 µmol/L for CYP2C8, and 27.31, 7.57, and 4.59 µmol/L for CYP2C9. The multiple-dose GLT increased rat CYP2C8 activity by 44% and 88%, respectively. DISCUSSION AND CONCLUSIONS: The metabolism of ROS is attenuated in the single dose of GLT by inhibiting CYP2C8 and CYP2C9 activity, and accelerated after the multiple-dose GLT treatment via inducing CYP2C8 activity in rats, indicating that the clinical dose of ROS should be adjusted when co-administrated with GLT.

Effects of the total flavonoid extracts and the monomers of Daphne genkwa on CYP2C8 activity.

This study aimed to assess the effects of total flavonoid extracts (TFDG) and the monomers of Daphne genkwa on the CYP2C8 activity in vitro and in vivo.The 50% inhibitory concentration (IC50) values were used to determine the inhibitory effect of TFDG and its four monomers for the CYP2C8 activity by recombinant human CYP2C8 (RHCYP2C8) yeast microsome system in vitro, and the volume per dose index (VDI) was predicted the potential inhibition in vivo. The effects of multiple-dose administration of TFDG on the pharmacokinetic parameters of rosiglitazone in rats were evaluated.The IC50 values of apigenin, luteolin, hydroxy-genkwanin, genkwanin, and TFDG were 7.27 µmol/L, 11.9 µmol/L, 28.1 µmol/L, 127 µmol/L, and 13.4 µg/mL, respectively. The VDI values of apigenin and TFDG were 2.15 L and 6.60 L. In vivo study, compared with the control group, the elimination phase half-life and mean residence time in the TFDG treatment group were significantly increased by 96.9% and 106.8% (p <.05), respectively.Apigenin showed a moderate inhibitory effect on the CYP2C8 activity in vitro, while the other three monomers were weak inhibitors. TFDG had a strong inhibitory effect on CYP2C8 in vitro and in vivo, and also inhibited the metabolism of rosiglitazone in rats.

Excessive selenium affects neural development and locomotor behavior of zebrafish embryos.

Selenium is an essential micronutrient derived from daily diet to maintain the normal growth and development of vertebrates. Excessive selenium intake will induce cardiovascular toxicity, reproductive toxicity and neurotoxicity. However, there have been few studies of the toxic effects of selenium on neural development and locomotor behavior. In this study, newly fertilized zebrafish embryos were treated with selenium. As a result, selenium treatment at the concentration of 0.5 µM decreased the moving speed and distance and blunted the touch response of zebrafish embryos. TUNEL assay and immunofluorescence analysis revealed that selenium induced nervous system impairment including promoted cell apoptosis, proliferation and neuroinflammation, and decreased neurons in zebrafish embryos. RNA-seq and RT-PCR results indicated that selenium treatment significantly decreased the expression of the dopaminergic neuron, motor neuron, GABAergic neuron and neurotransmitter transport marker genes in zebrafish embryos. The expression of PPAR signaling pathway marker genes was significantly down-regulated in selenium-treated embryos. Two PPAR agonists (rosiglitazone and bezafibrate) and an anti-cancer drug (cisplatin) were tested for their effects to alleviate selenium-induced locomotor defects. Rosiglitazone and bezafibrate could restore the expression of some neural marker genes but could not fully rescue the selenium-induced locomotor behavior defects. The supplementation of cisplatin could restore the dysfunctional locomotor behavior and the abnormal expression of the PPAR and neural marker genes to almost the normal levels. In conclusion, the results of this study reveal that selenium-induced neural development and locomotor behavior defects are caused by multiple complex factors including PPAR signaling, and all the factors might be recovered by cisplatin through unknown mechanisms.

18:0 Lyso PC, a natural product with potential PPAR-γ agonistic activity, plays hypoglycemic effect with lower liver toxicity and cardiotoxicity in db/db mice.

Rosiglitazone, a specific agonist of peroxisome proliferator-activated receptor-γ (PPAR-γ), displays a robust hypoglycemic action in patients with type 2 diabetes mellitus (T2DM) and elicits serious adverse reactions, especially hepatotoxicity and cardiotoxicity. Here, we aims to find a new natural PPAR-γ agonist with less adverse reactions than rosiglitazone in db/db mice. The method of virtual screening was used to identify a PPAR-γ agonist 18:0 Lyso PC from an in-house natural product library. We verified its pharmacological effects and adverse reactions comparing with rosiglitazone in vivo and in vitro. 18:0 Lyso PC exhibited pharmacological effects similar to those of rosiglitazone in db/db mice. Moreover, 18:0 Lyso PC showed a lower extent of liver injury and cardiotoxicity in db/db mice. The mechanism, by which this natural compound alleviates metabolic syndrome, involves a reduction in fatty acid synthesis mediated by activation of the phosphorylation of adenosine 5'-monophosphate (AMP)-activated protein kinase-alpha (AMPKα) and acetyl-CoA carboxylase (ACC) and an increase expression of uncoupled protein 1 (UCP1) and PPAR-γ coactivator-1 alpha (PGC1-α). 18:0 Lyso PC, a natural compound, can show a similar hypoglycemic effect to rosiglitazone by activating PPAR-γ, while eliciting markedly fewer adverse reactions than rosiglitazone.

Omega-3 fatty acid-rich fish oil supplementation prevents rosiglitazone-induced osteopenia in aging C57BL/6 mice and in vitro studies.

Rosiglitazone is an effective insulin-sensitizer, however associated with bone loss mainly due to increased bone resorption and bone marrow adiposity. We investigated the effect of the co-administration of fish oil rich in omega-3 fatty acids (FAs) on rosiglitazone-induced bone loss in C57BL/6 mice and the mechanisms underlying potential preventive effect. Mice fed the iso-caloric diet supplemented with fish oil exhibited significantly higher levels of bone density in different regions compared to the other groups. In the same cohort of mice, reduced activity of COX-2, enhanced activity of alkaline phosphatase, lower levels of cathepsin k, PPAR-γ, and pro-inflammatory cytokines, and a higher level of anti-inflammatory cytokines were observed. Moreover, fish oil restored rosiglitazone-induced down-regulation of osteoblast differentiation and up-regulation of adipocyte differentiation in C3H10T1/2 cells and inhibited the up-regulation of osteoclast differentiation of RANKL-treated RAW264.7 cells. We finally tested our hypothesis on human Mesenchymal Stromal Cells differentiated to osteocytes and adipocytes confirming the beneficial effect of docosahexaenoic acid (DHA) omega-3 FA during treatment with rosiglitazone, through the down-regulation of adipogenic genes, such as adipsin and FABP4 along the PPARγ/FABP4 axis, and reducing the capability of osteocytes to switch toward adipogenesis. Fish oil may prevent rosiglitazone-induced bone loss by inhibiting inflammation, osteoclastogenesis, and adipogenesis and by enhancing osteogenesis in the bone microenvironment.

Non-alcoholic fatty liver disease and steatohepatitis: State of the art on effective therapeutics based on the gold standard method for diagnosis.

OBJECTIVE: The prevalence of non-alcoholic fatty liver disease and non-alcoholic steatohepatitis (NAFLD/NASH) is increasing. NAFLD/NASH may progress to cirrhosis and hepatocellular carcinoma. However, most patients with NAFLD/NASH will die from a vascular cause. There are no approved pharmacological treatments for NASH/NAFLD. Many clinical trials have been, or are being, undertaken; however, the challenge is the assessment of the clinical endpoint. The main objective of this narrative review was to evaluate the efficacy of drugs used in clinical trials for the treatment of NAFLD/NASH that included a liver biopsy as the gold standard. METHODS: A literature search was conducted using 3 databases (PubMed, Scopus, and Google Scholar) to identify the clinical trials that included liver biopsy assessment before and after treatment. RESULTS: Interventional clinical trials (n = 33) involving 18 different agents, alone and in combination, were identified. Pioglitazone is the only agent that has shown consistent benefit and efficacy in clinical trials. Pentoxifylline, rosiglitazone, and ursodeoxycholic acid had both positive and negative results from clinical trials. There is also evidence for vitamin E and metformin. Other drugs, including bicyclol, cysteamine bitartrate, l-carnitine, liraglutide, obeticholic acid, oligofructose, selonsertib, silymarin, and statins, each had a single clinical study. CONCLUSIONS: In summary, the available molecules demonstrated a significant improvement in NASH and/or liver fibrosis in a minority of patients; thus, other drugs should be identified, possibly those acting on alternative pathophysiological pathways, and tested for their safety and efficacy.

The Rosmarinus Bioactive Compound Carnosic Acid Is a Novel PPAR Antagonist That Inhibits the Browning of White Adipocytes.

Thermogenic brown and brite adipocytes convert chemical energy from nutrients into heat. Therapeutics that regulate brown adipocyte recruitment and activity represent interesting strategies to control fat mass such as in obesity or cachexia. The peroxisome proliferator-activated receptor (PPAR) family plays key roles in the maintenance of adipose tissue and in the regulation of thermogenic activity. Activation of these receptors induce browning of white adipocyte. The purpose of this work was to characterize the role of carnosic acid (CA), a compound used in traditional medicine, in the control of brown/brite adipocyte formation and function. We used human multipotent adipose-derived stem (hMADS) cells differentiated into white or brite adipocytes. The expression of key marker genes was determined using RT-qPCR and western blotting. We show here that CA inhibits the browning of white adipocytes and favors decreased gene expression of thermogenic markers. CA treatment does not affect ß-adrenergic response. Importantly, the effects of CA are fully reversible. We used transactivation assays to show that CA has a PPARα/γ antagonistic action. Our data pinpoint CA as a drug able to control PPAR activity through an antagonistic effect. These observations shed some light on the development of natural PPAR antagonists and their potential effects on thermogenic response.

Hypothesis validation of rosiglitazone a potential inhibitor against glycogen synthase kinase-3ß, for the management of multifaceted pathophysiology of the diabetic wound: An insilico study.

Diabetic wound (DW) is a major complication of diabetes mellitus that often ends up with amputation of the concerned organ. The current therapies for DW include glucose regulation, wound debridement, pressure off-loading, surgeries, hyperbaric oxygen therapy, maggot therapy, and so on. However, the majority are not meeting all the prerequisites of DW because of extensive pathology and cost associated with the strategies. So, to overcome the problems related to the existing conventional therapies, we hypothesized to repurpose the current drugs, which can target a receptor having a considerable role in the progression of DW might be beneficial. One major challenge of DW is multifaceted pathophysiology includes prolonged inflammation, increased infections, decreased cell proliferation, and migration. Many shreds of evidence disclosed that inhibition of GSK-3ß could result in reduced inflammation and infection, followed by increased cell proliferation and migration. Thus, we selected the GSK-3ß receptor as a ubiquitous target for the treatment of multifactorial pathophysiology of DW. In the current hypothetical study, we investigated the use of rosiglitazone as a therapeutic modulator against the GSK-3ß receptor. To validate our hypothesis, computational studies such as molecular docking and MMGBSA were performed. From the in silico methods, it is evident that rosiglitazone established a higher binding affinity against the selected receptor. Further, the Molecular Dynamic simulation study has revealed stable interaction of rosiglitazone against GSK-3ß complex. Thus, rosiglitazone might be a drug of choice in the therapeutic management of DW.

Antifibrotic Effects of the Thiazolidinediones in Eosinophilic Esophagitis Pathologic Remodeling: A Preclinical Evaluation.

INTRODUCTION: Eosinophilic esophagitis (EoE) is a T-helper 2 (Th2), eosinophilic disease associated with pathologic tissue remodeling that leads to end-organ dysfunction. During early-stage disease, inflammation and subepithelial fibrosis are coupled and reversible, but in late-stage or therapy-resistant disease, there can be uncoupling of these features with progressive esophageal rigidity and strictures contributing to clinical dysphagia and food impactions. No current pharmacotherapeutic interventions directly target esophageal fibrosis. Based on the ability of the thiazolidinediones (TZD) to regulate intestinal and hepatic fibrosis, we tested the antifibrotic effects of the TZDs, rosiglitazone and pioglitazone, in preclinical studies using primary human esophageal fibroblasts. METHODS: Primary fibroblasts isolated from normal or EoE esophagi were treated with transforming growth factor (TGF)-ß1 in the absence or presence of TZDs and, in some experiments, without or with budesonide and analyzed by quantitative real-time PCR and immunoblotting. Immunohistochemical analysis of human esophageal biopsies was performed. RESULTS: EoE esophageal biopsies and esophageal fibroblasts expressed higher levels of the TZD receptor, peroxisome proliferator-activated receptor-γ (PPAR-γ), than normal controls. PPAR-γ was inducible by the Th2 cytokine, interleukin 4 (IL-4). TZD significantly reduced TGF-ß1-induced myofibroblast and fibrotic gene and protein expression preferentially in EoE, but not normal esophageal fibroblasts. In esophageal fibroblasts, TGF-ß1 increased phosphorylated Smad2/3 and p38, but TZDs preferentially inhibited p38 phosphorylation, suggesting signaling pathway-specific effects. The TZDs were more potent than budesonide at decreasing collagen-1α1 expression. DISCUSSION: The TZDs preferentially exert antifibrotic effects in TGF-ß1-activated EoE fibroblasts and provide a preclinical foundation for further investigation of the potential of the TZDs in EoE pathologic remodeling.

Indirubin promotes adipocyte differentiation and reduces lipid accumulation in 3T3­L1 cells via peroxisome proliferator­activated receptor γ activation.

The peroxisome proliferator­activated receptor Î³ (PPARγ) plays an important role in insulin sensitivity and adipocyte differentiation. It is known as ligand­receptor that improves insulin sensitivity in type 2 diabetes mellitus. Several kinds of indigo plant have been already used to treat diabetes in oriental traditional medicine, but its mechanism has not been clarified yet. To investigate the effect of indirubin, which is a component of Polygonum tinctorium on the cell differentiation and adipprocess in 3T3­L1 cells, 3T3­L1 cells were cultured to determine the effect of cell differentiation and glucose uptake with indirubin. As a result, Indirubin compound enhanced adipocyte differentiation in 3T3­L1 cells similar to rosiglitazone. This effect was terminated by cotreatment with GW9662, a PPARγ antagonist. In mature 3T3­L1 adipocytes, the lipid droplet size and accumulation were reduced by this compound. The basal and insulin­stimulated glucose uptakes were also significantly increased. In addition, indirubin treatment significantly enhanced estrogen level by 1.64­fold with mature adipocytes which can be attributed to its aromatase activity. Conclutionaly, this finding suggested that indirubin is a potential anti­diabetic compound for type 2 diabetes mellitus by promoting adipocyte differentiation and glucose uptake via PPARγ.

(-)-O-Methylcubebin from Vitex trifolia Enhanced Adipogenesis in 3T3-L1 Cells via the Inhibition of ERK1/2 and p38MAPK Phosphorylation.

In this study, for the purpose of elucidation for antidiabetic components, we isolated and identified compounds that could become lead compounds for the development of antidiabetic agents from the herbal medicine Vitex trifolia, which is used for liver protection in Myanmar. Three kinds of lignan, (-)-O-methylcubebin (MC), (-)-hinokinin, and (-)-cubebin, were isolated from the ethyl acetate extract of the leaves of V. trifolia, using various chromatography. Among the three isolated compounds, MC showed the strongest effects to increase intracellular lipid accumulation in 3T3-L1 cells. From the results of the elucidation of the MC's effects on the adipogenesis of 3T3-L1 cells, the downsizing of adipocytes and the promotion of the expression of adipogenesis-related proteins, as well as adiponectin, were observed. On the other hand, since the activity of MC was inhibited by antagonists of PPARγ and improved by inhibitors of the classical mitogen-activated protein kinase (MAPK) pathway and p38MAPK pathway, MC was considered to be an agonist of PPARγ, and furthermore promoted adipogenesis via the inhibition of extracellular signal-regulated kinase 1/2 (ERK1/2) and p38MAPK phosphorylation. Although MC showed similar effects to those of rosiglitazone (RO) used as a positive control, RO promoted the migration of GLUT4 from the cytoplasm to the cell membrane, whereas MC did not show such an effect. From the abovementioned results, it was considered that MC could be a lead compound for the development of antidiabetic drugs that does not show weight gain, which is a side effect of RO.