The effect of saraglitazar on TGF-ß-induced smad3 phosphorylation and expression of genes related to liver fibrosis in LX2 cell line.

BACKGROUND AND PURPOSE: Liver fibrosis is a reversible liver injury that occurs as a result of many chronic inflammatory diseases and can lead to cirrhosis, which is irreversible and fatal. So, we studied the anti-fibrotic effects of saroglitazar on LX-2 cell lines, as a dual PPARα/γ agonist. METHODS: Cells, after 80% confluence, were treated with TGF-ß (2 ng/mL) for 24 h. Then cells were treated with saroglitazar at different doses (2.5, 5, 10 µM) for 24 h. After same incubation, the cells of control group, TGF-ß group, and TGF-ß + saroglitazar group were harvested for RNA and protein extraction to determine the effects of saroglitazar. RT-PCR and western blot methods were used to express genes related to fibrosis. RESULTS: Our results show that the relative expression of α-SMA, collagen1α, N-cadherin, NOX (1, 2, and 4), and phosphorylated Smad3 protein was significantly higher in TGF-ß-treated cells compared with the normal group, and E-cadherin expression was decreased in TGF-ß-treated cells. After TGF-ß-treated cells were exposed to saroglitazar, the expression of these genes was significantly reversed (P < 0.05). CONCLUSIONS: Our results clearly show the short-term inhibitory role of saroglitazar in the expression of fibrotic factors using the TGF-ß/Smad signaling pathway. These results suggest that saroglitazar can be considered as a suitable therapeutic strategy for fibrotic patients. Although more studies are needed.

Cardioprotective effect of tamoxifen and raloxifene: Preventing proteoglycan synthesis by modulating non-canonical TGF-ß signalling through NADPH oxidase and ERK phosphorylation.

Atherosclerosis, a leading cause of cardiovascular disease, remains a significant global health concern. Tamoxifen and raloxifene, selective estrogen receptor modulators (SERMs), have demonstrated potential cardioprotective effects. However, the underlying molecular mechanisms by which these SERMs modulate Transforming Growth Factor-ß (TGF-ß) signaling in human vascular smooth muscle cells (VSMCs) remain largely unexplored. This study sought to investigate the impact of tamoxifen and raloxifene on TGF-ß-induced CHSY1 expression and Smad2 linker region phosphorylation in VSMCs and to elucidate the role of reactive oxygen species (ROS), NADPH oxidase (NOX), and kinase pathways in mediating these effects. Employing a comprehensive experimental strategy, VSMCs were treated with TGF-ß in the presence or absence of tamoxifen, raloxifene, and various pharmacological inhibitors. Subsequently, CHSY1 mRNA expression, Smad2C and Smad2L phosphorylation, ROS production, p47phox and ERK 1/2 phosphorylation were assessed. Our results revealed that tamoxifen and raloxifene significantly attenuated TGF-ß-mediated CHSY1 mRNA expression and Smad2 linker region phosphorylation, without affecting the canonical TGF-ß-Smad2C pathway. Furthermore, these compounds effectively inhibited ROS production, p47phox and ERK 1/2 phosphorylation, implicating the involvement of the TGF-ß-NOX-ERK-Smad2L signaling cascade in their cardioprotective properties. This study provides a comprehensive understanding of the molecular mechanisms underlying the cardioprotective effects of tamoxifen and raloxifene in VSMCs, offering valuable insights for the development of targeted therapeutic strategies aimed at atherosclerosis prevention and the promotion of cardiovascular health.

Type 2 Diabetes Mellitus Coincident with Clinical and Subclinical Thyroid Dysfunctions Results in Dysregulation of Circulating Chemerin, Resistin and Visfatin.

The alterations of circulating adipocytokines have been reported in thyroid diseases or type 2 diabetes mellitus (T2DM), but such data in T2DM coincident with clinical and subclinical thyroid-dysfunctions are limited, and remain to be investigated. We studied the changes in serum chemerin, resisitin and visfatin in T2DM patients with thyroid dysfunctions, and their association with inflammatory and insulin resistance-markers. A total of 272 female and male Iranian participants were selected and divided into six groups: the euthyroid group, T2DM, T2DM coincident with clinical and sub clinical hypothyroidism (SC-HO, and C-HO), and T2DM coincident with clinical and sub clinical hyperthyroidism (SC-HR, C-HR).Demographic characteristics, serum levels of adipocytokines, thyroid hormones, inflammatory factors (IL1-ß, IL-6 and CRP) and insulin resistance-markers were determined in all participants. T2DM patients with clinical thyroid dysfunctions showed higher levels of circulating resistin, visfatin, chemerin and inflammatory factors, compared with the T2DM group and T2DM coexisted with subclinical thyroid diseases. No significant differences were observed in circulating adipocytokines and inflammatory markers between T2DM coexisting with subclinical thyroid diseases and those without thyroid dysfunctions. Our results revealed that clinical thyroid dysfunction in T2DM patients was associated with elevated levels of circulating resistin, chemerin, visfatin and inflammatory factors, while no such alteration was detected in T2DM coincident with subclinical thyroid dysfunction.

Examining dyslipidaemia, metabolic syndrome and liver enzyme levels in patients with prediabetes and type 2 diabetes in population from Hoveyzeh cohort study: A case-control study in Iran.

INTRODUCTION: Type 2 diabetes mellitus (T2DM) is among the world's top 10 leading causes of death. Additionally, prediabetes is a major risk factor for diabetes. Identifying diabetes co-occurring disorders can aid in reducing adverse effects and facilitating early detection. In this study, we evaluated dyslipidaemia, metabolic syndrome (MetS), and liver enzyme levels in pre-diabetic and T2DM patients in the Persian cohort compared to a control group. MATERIALS AND METHODS: In this cross-sectional study, 2259 pre-diabetes, 1664 T2DM and 5840 controls (35-70 years) who were selected from the Hoveyzeh cohort centre were examined. Body mass index, blood pressure, fasting blood glucose (FBG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), triglyceride (TG) and liver enzymes: γ-glutamyltransferase (GGT), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined using the standard protocols. MetS subjects were also identified based on the National Cholesterol Education Program guidelines. RESULTS: Prediabetes and T2MD were closely correlated with the lipid profile, MetS, and liver enzymes (ALT, GGT, ALT/AST). MetS increases the risk of T2DM by 12.45 [95% CI: 10.88-14.24] fold, while an increase in ALT/AST ratio increases the risk of T2DM by 3.68 [95% CI: 3.159-4.154] fold. ROC curve analysis also revealed the diagnostic roles of GGT, ALT, AST and the ALT/AST ratio among pre-diabetics, diabetics and the control group. The GGT level corresponds to the highest AUCs (0.685) with the highest sensitivity (70.25%). CONCLUSIONS: Our results indicated a significant increase in liver enzymes, lipid profile and MetS status in both pre-diabetic and T2MD subjects, with the differences being more pronounced in diabetic individuals. Consequently, on the one hand, these variables may be considered predictive risk factors for diabetes, and on the other hand, they may be used as diagnostic factors. In order to confirm the clinical applications of these variables, additional research is required.

Effectiveness of the pomegranate extract in improving hepatokines and serum biomarkers of non-alcoholic fatty liver disease: A randomized double blind clinical trial.

BACKGROUND AND AIM: Pomegranate as a functional food has various properties and effects on health. The aim of the study was to evaluate the effect of pomegranate extract on serum levels of liver enzymes, hepatokines, interleukin-6 (IL-6), and total antioxidant capacity in non-alcoholic fatty liver disease (NAFLD). METHODS: In this double-blind randomized clinical trial, 44 patients with NAFLD were divided into two groups: pomegranate extract tablets and placebo. The intervention period was 12 weeks. At the beginning and end of the study, serum levels of alanine transaminase (ALT), aspartate transaminase (AST), gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), fetuin-A, fibroblast growth factor 21 (FGF-21), interleukin-6 (IL-6), and total antioxidant capacity were assessed in both groups. RESULTS: Pomegranate extract reduced the level of ALT (P < 0.001), AST (P < 0.001), GGT (P < 0.001), fetuin-A (P < 0.001), FGF-21(P < 0.001) and IL-6 (P = 0.04) compared to the placebo. Pomegranate extract also led to an increase in total antioxidant capacity (P˂0.001) but had no effect on ALP. CONCLUSION: It seems that the pomegranate extract improves several markers of NAFLD, and can be useful as a treatment supplement. The clinical trial approved by Nutrition and Metabolic Diseases Research Center, Ahvaz Jundishapur University of Medical Sciences (grant No. NRC-9811). TRIAL REGISTRATION: Iranian Registry of Clinical Trials (IRCT), IRCT20140107016123N14, https://www.irct.ir/trial/42739.

Capparis spinosa improves non-alcoholic steatohepatitis through down-regulating SREBP-1c and a PPARα-independent pathway in high-fat diet-fed rats.

OBJECTIVE: Non-alcoholic steatohepatitis (NASH) has become a global medical problem. Currently, there is no approved pharmacologic treatment for this condition. Previous studies have suggested that in the pathogenesis of this disease, regulatory pathways associated with de novo lipogenesis and ß-oxidation pathways genes are misregulated. Capparis spinosa (CS) belongs to the family of Capparidaceae and is a traditional plant used to treat various diseases, particularly dyslipidemia. The compounds and extracts of this plant in In vivo and in vitro studies resulted in a reduction in lipid profiles and glucose. However, the mechanism of these effects remains unknown. This study aimed to evaluate the effects of (CS) fruit extract on NASH compared to fenofibrate and explored the related molecular mechanism. RESULTS: In the rats (n = 40) model of NASH, biochemical and histopathological examinations showed that liver steatosis, inflammation, and hepatic fibrosis were markedly attenuated in response to CS and fenofibrate interventions. At the molecular level, CS treatment down-regulated sterol regulatory element-binding protein-1c (SREBP-1c) (p < 0.001), acetyl-CoA carboxylase (ACC) (p < 0.001), and up-regulated Carnitine palmitoyltransferase I (CPT1) expression (p < 0.001). In conclusion, CS has favorable therapeutic effects for NASH, which was associated with ameliorating steatosis and fibrosis via regulation of the DNL and ß-oxidation pathway genes.

Effect of Quercetin on the fructose-activated human hepatic stellate cells, LX-2, an in-vitro study.

BACKGROUND: Hepatic fibrosis is one of the main reasons for mortality in the world. Hepatic stellate cells (HSCs) activate during chronic liver injury, express more Transforming growth factor beta (TGF-ß), Collagen1α (COLA1) and actin-alpha smooth muscle (αSMA) that lead to hepatic fibrosis. Quercetin is a flavonoid in vegetables and fruits that has shown hepatoprotective potential, but little is known about its effects on HSCs activation. In this study, we investigated the antifibrotic activity of Quercetin on fructose-activated human HSCs and its underlying mechanism in vitro. METHODS: First, the human HSCs were treated with fructose (25 mM) for 48 h and then with Quercetin for 24 h. Total RNAs were extracted, reversely transcribed into cDNA, Quantitative Real-time PCR and western blot were performed. RESULTS: The results showed that the levels of mRNA expression of TGF-ß, αSMA, Collagen1 genes, and phosphorylated smad3 protein were significantly reduced in fructose-activated HSCs after treatment with Quercetin compared to fructose-activated HSCs. CONCLUSION: Quercetin is effective in reducing the expression of fibrogenic genes in fructose-activated human HSCs through downregulation of the TGF-ß/smad3 signaling pathway. Therefore, Quercetin possesses significant antifibrotic properties in hepatic fibrosis.

Saroglitazar improved hepatic steatosis and fibrosis by modulating inflammatory cytokines and adiponectin in an animal model of non-alcoholic steatohepatitis.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) have become significant global health concerns. In the present study, we aimed to investigate the effects of saroglitazar, a dual PPARα/γ agonist, fenofibrate, a PPAR-α agonist, and pioglitazone, a PPAR-γ agonist on an animal model of NASH. METHODS: Male Wistar rats were fed a high-fat (HF) emulsion via gavage for 7 weeks to induce NASH. The HF-treated rats were grouped into four groups to receive saroglitazar, pioglitazone, fenofibrate, or vehicle. We measured body and liver weight, liver enzymes, serum levels of adiponectin and leptin. We also performed histopathological examinations and gene expression analysis of interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF- α), transforming growth factor-beta (TGF-ß), and monocyte chemoattractant protein 1 (MCP-1). RESULTS: Body weight was markedly normalized by both saroglitazar and fenofibrate, while the liver index only decreased significantly with saroglitazar. Saroglitazar corrected ALT, AST, leptin, and adiponectin levels better than pioglitazone and fenofibrate. All PPAR agonists significantly attenuated the upregulation of the proinflammatory and TGF-ß genes, which correlated with the improved steatosis, inflammation of liver tissue, and fibrotic lesions. CONCLUSIONS: As documented by our results, the dual activation of PPARα/γ by saroglitazar could effectively improve steatosis, fibrosis, and aspects of necro-inflammation in the HF-induced NASH model more than fenofibrate and pioglitazone, and it can be more beneficial in the management of NASH.

The effect of pomegranate extract on anthropometric indices, serum lipids, glycemic indicators, and blood pressure in patients with nonalcoholic fatty liver disease: A randomized double-blind clinical trial.

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. The beneficial effects of pomegranate have been shown on insulin resistance and obesity, which are linked to NAFLD pathogenesis. The aim of this study was to investigate the efficacy of pomegranate extract in patients with NAFLD. Forty-four NAFLD patients were randomly assigned to receive two pomegranate extract tablets or placebo for 12 weeks. Anthropometric measurements, serum lipids, glycemic indicators, and blood pressure were assessed at baseline and the end of the study. Pomegranate was associated with a reduction in the total cholesterol (p Ë‚ .001), triglyceride (p Ë‚ .001), low-density lipoprotein cholesterol (LDL-C)-to-high-density lipoprotein cholesterol (HDL-C) ratio (p Ë‚ .003), fasting blood sugar (p Ë‚ .001), homeostatic model assessment of insulin resistance (p = .02), diastolic blood pressure (p = .04), weight (p Ë‚ .001), body mass index (p Ë‚ .001), and waist circumference (p = .002), as compared to placebo. A significant increase was observed in serum HDL-C (p Ë‚ .001) after intervention with the pomegranate extract. However, no significant difference was shown between the two groups in serum insulin and LDL-C. The pomegranate extract supplement could be used as a complementary therapy along with existing therapies to improve glycemic indicators, serum lipids, anthropometric indices, and blood pressure in patients with nonalcoholic fatty liver.

Association between the rs615563 variant of PCSK9 gene and circulating lipids and Type 2 diabetes.

OBJECTIVE: Many different genetic variants of proprotein convertase subtilisin kexin 9 (PCSK9) are related to the serum levels of cholesterol and LDL cholesterol (LDL-C). The rs615563 variant of PCSK9 (a gain-of-function mutation) is associated with increased triglycerides and cholesterol levels, but its association with the incidence of diabetes is not well defined. This study aimed to investigate the relationship between the PCSK9 rs615563 variant with the incidence of type 2 diabetes. The data reported in this study are based on subsamples from a 5-year (2009-2014) cohort study of the adult population (590 subjects) aged 20 years and older. The rs615563 polymorphism was genotyped using polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP) analysis. RESULTS: The distribution of PCSK9 rs615563 genotypes was not significantly different between the diabetic and non-diabetic individuals. The incidence of diabetes after five-years of follow-up was not different between the genotypes. Our findings also showed no significant relationship between this polymorphism and serum lipid parameters. The data extracted from our cohort study do not support the findings that the gain-of-function mutations of PCSK9 predispose to the incidence of type 2 diabetes.

The efficacy of calcitriol treatment in non-alcoholic fatty liver patients with different genotypes of vitamin D receptor FokI polymorphism.

BACKGROUND: Vitamin D deficiency is prevalent in patients with non-alcoholic fatty liver disease (NAFLD), but there are debates on the usefulness of vitamin D treatment. The interindividual variations in response may be due to different genetic backgrounds. The present study evaluated the efficacy of calcitriol treatment in NAFLD patients with regard to the vitamin D receptor (VDR) genotypes of FokI polymorphism. METHODS: The study was conducted on 128 NAFLD patients randomly divided into two groups and were subjected to intervention with 0.25 mcg calcitriol/day or placebo for 4 months, while anthropometric parameters, glycemic status, lipid profiles, inflammatory markers, liver enzymes, and fatty liver indices were measured. The ARMS-PCR method was used to genotype the VDR FokI polymorphism. RESULTS: Calcitriol treatments along with weight loss and diet recommendations decreased the liver enzymes (AST, ALT, and ALP, p < 0.001 for all) and fatty liver indices (HSI, p < 0.01 and APRI, p < 0.001), compared to the baseline. But when the calcitriol effects were compared to the placebo group, only ALP decrease remained significant (17.5 IU. P = 0.02). The prevalent FokI variants in our population were FF (53.1%) and Ff genotype (45.3%). No significant interaction of FokI variants to the calcitriol effects was found except for ALP. The decrease in the ALP activity was higher in calcitriol-received patients with the Ff genotype (p = 0.05). CONCLUSIONS: The FF and Ff variants of VDR FokI polymorphism did not interact with the effects of calcitriol on fatty liver, but the ALP was more responsive in subjects with the Ff variant. IRCT REGISTRATION NUMBER: IRCT2017053034222N1 Registration date: 2017-06-28 - Retrospectively registered, https://en.irct.ir/trial/26203.

Capparis spinosa improves the high fat diet-induced non-alcoholic steatohepatitis in rats: the possible role of FGF21.

OBJECTIVES: This study focused on the beneficial effects of Capparis spinosa (CS) treatment on the steatohepatitis induced by the administration of a high-fat emulsion in rats. Changes of hepatic expression and secretion of fibroblast growth factor 21 (FGF21) were also evaluated as a probable mechanism of the CS effects on fatty liver. Male Wistar rats were allocated in different groups to receive a normal diet (NC group), a high-fat diet (HF group), or the high-fat emulsion plus CS extract at a dose of 20 mg/kg (HF+CS group). Body and liver weight, liver index, serum biochemical factors, histopathological examination, and serum level and hepatic gene expression of FGF21 were determined. RESULTS: CS administration markedly reduced liver weight and index, serum levels of glucose, lipids, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) and improved histological features of nonalcoholic steatohepatitis (NASH) which were induced by HF feeding in this model. CS supplementation also restored the decreased hepatic and serum FGF21 levels in the fatty liver rats. We propose that the FGF21 up-regulation may partly account for the favorable effects of CS in this steatohepatitis model.

Assessing agreement between the three common clinical measurement methods of HbA1c.

Reliable measurement of hemoglobin A1c (HbA1c) has great importance in the diagnosis and monitoring of diabetes mellitus. The aim of the present study was to compare the performance parameters of the three common methods of HbA1c assay, including the Roche, Sebia and TOSOH G8 systems. We studied 120 patients referred to a clinical laboratory for HbA1c assay. The blood samples were analyzed with the Roche, Sebia and TOSOH G8 systems based on immunoassay, capillary electrophoresis, and ion-exchange chromatography techniques, respectively. The Spearman and the Passing-Bablok regression,as well as the Bland-Altman plots, were used to compare these methods. For each assay, the patients' classification was evaluated at the three cut-points of 6.5, 7, and 8% and the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the methods were estimated. Our results showed that there were good correlations and agreement between the methods. We found a mean difference of 0.07% for the TOSOH G8 vs. Roche, 0.06% for the TOSOH G8 vs. Sebia and - 0.01% for the Roche vs. Sebia. The methods represented very low bias, indicating the good accuracy of the results. The sensitivity and specificity of the methods were comparable as well. The three methods also performed similarly in the classification of patients at the proposed cut-off points. Based on our results, the Roche, Sebia and TOSOH G8 systems showed a very high level of agreement with comparable performance parameters and yielded similar and accurate classification of diabetic patients. Therefore, these methods can be used interchangeably.

Protective effect of inulin on methotrexate- induced liver toxicity in mice.

Methotrexate (MTX) is an effectively used drug in the treatment of cancer and inflammatory diseases but, its use is related with hepatotoxicity. Inulin with antioxidant properties has hepatoprotective effects. In this research, we assessed inulin effects on MTX-induced liver toxicity. 48 male mice were randomly assigned into 6 equal groups. Mice were Pre-treatment with inulin (100, 200 and 400 mg/kg) for 9 consecutive days, orally) and MTX (10 mg/kg, intraperitoneally) was received on the 7th, to 9th day. Blood and liver were collected to assess liver functional test in serum samples and Stress oxidative biomarkers, pathological changes, the expressions levels of apoptotic factors, such as, Bcl-2, caspase -3 and miR-122 in the mice liver. The results indicated that MTX administration induced marked liver damage and serums factors of all of the mice. Furthermore, there was a decrease in the Bcl2 and an increase in the caspase-3 activity and miR-122 expression compared to the control group. Instead, inulin Pre-treatment clearly improved these variations induced by MTX. Finally, our results revealed the new evidence that the hepatoprotective effects of inulin might be mediated via the modulations of apoptotic and oxidative stress factors.

Effects of palmitate and astaxanthin on cell viability and proinflammatory characteristics of mesenchymal stem cells.

Mesenchymal stem cells (MSCs) have broad immunomodulatory activities. These cells are a stable source of cytokine production such as interleukin-6 (IL6), monocyte chemoattractant protein-1 (MCP-1/CCL2) and vascular endothelial growth factor (VEGF). Fatty acid elevation in chronic metabolic diseases alters the microenvironment of MSCs and thereby, might affect their survival and cytokine production. In the present study, we investigated the effects of palmitate, the most abundant saturated free fatty acid (FFA) in plasma, and astaxanthin, a potent antioxidant, on cell viability and apoptosis in human bone marrow-driven mesenchymal stem cells. We also elucidated how palmitate and astaxanthin influence the inflammation in MSCs. Human mesenchymal stem cells were collected from an aspirate of the femurs and tibias marrow compartment. The effect of palmitate on cell viability, caspase activity and pro-inflammatory cytokines expression and secretion were evaluated. In addition, activation of the MAP kinases and NF-kB signaling pathways were investigated. The results showed that astaxanthin protected MSCs from palmitate-induced cell death. We found that palmitate significantly enhanced IL-6, VEGF and MCP-1 expression, and secretion in MSC cells. Increased cytokine expression was parallel to the enhanced phosphorylation of P38, ERK and IKKα-IKKß. In addition, pretreatment with JNK, ERK, P38, and NF-kB inhibitors could correspondingly attenuate palmitate-induced expression of VEGF, IL-6, and MCP-1. Our results demonstrated that fatty acid exposure causes inflammatory responses in MSCs that can be alleviated favorably by astaxanthin treatment.

Association between Vascular Endothelial Growth Factor Plasma Levels and rs699947 Polymorphism and Coronary Collateral Vessel Formation.

Background: The vascular endothelial growth factor (VEGF), as an angiogenic cytokine, binds endothelial cell receptors and stimulates angiogenesis and collateral formation. We evaluated the association between VEGF plasma levels and the gene polymorphism rs699947 and the formation of coronary collaterals in patients with coronary artery disease. Methods: A total of 195 patients with ≥70% narrowing in at least 1 coronary vessel (according to coronary angiography) were included in the study. The presence of the rs699947 polymorphism within the promoter of the VEGF gene was investigated using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The plasma VEGF concentration was quantified via the ELISA method. The Rentrop method was used to grade the extent of collateral development. Results: There was no significant difference in VEGF levels between the groups with good and poor collaterals. The frequency of the A allele of rs699947 was found to be higher in the patients with good collaterals than in those with poor collaterals (P=0.014). The odds ratio of good collaterals for AA was 2.67 (P=0.025) when compared with the CC genotype. Further, our additive model revealed an association between the rs699947 polymorphism and collateral formation (OR: 1.96, 95% CI: 1.05-3.65, P=0.033). Conclusion: The rs699947 polymorphism might be a novel genetic factor affecting collateral development in Iranian patients with coronary artery disease.

Investigating the effects of Capparis Spinosa on hepatic gluconeogenesis and lipid content in streptozotocin-induced diabetic rats.

The present study aimed to investigate the effects of administration of Capparis spinosa (CS) fruit aqueous extract on liver metabolism in streptozotocin (STZ)-induced diabetic rats. The aqueous extract of CS was orally administered at a dose of 20mg/kg for 28 consecutive days and then its effects on blood glucose, lipid and insulin levels in normal and STZ diabetic rats were comparatively investigated. Furthermore, the effects of CS on the activity and expression of the key enzymes of gluconeogenesis and hepatic lipid content were investigated. The results showed that administration of CS extract in the STZ diabetic rats significantly decreased blood glucose level, while no significant influence on the insulin level. In addition, CS significantly decreased blood and liver triglyceride and cholesterol content in STZ diabetic rats. Furthermore, CS administration significantly reduced the mRNA expression and enzyme activities of glucose-6- phosphatase and phosphoenolpyruvate carboxykinase in liver tissues. Our findings demonstrated the beneficial effects of CS on blood glucose and lipid levels in an insulin- independent manner. This study also showed that CS improved the circulating levels of triglyceride and cholesterol. In addition, direct inhibition of gluconeogenesis in liver may be a probable mechanism of action of this plant. Since CS also decreased liver lipid content, we suggest that CS administration might be a beneficial therapeutic approach for metabolic syndrome and fatty liver.

Palmitate-induced PTP1B expression is mediated by ceramide-JNK and nuclear factor κB (NF-κB) activation.

Palmitate induces PTP1B expression in skeletal muscle cells. The purpose of this study was to investigate the mechanisms responsible for palmitate-induced PTP1B expression in mouse skeletal muscle cells. Three truncated fragments of PTP1B promoter were cloned into PGL3-basic vector and the promoter activity of PTP1B was assessed in C2C12 cells exposed to palmitate either in the presence or in the absence of several inhibitors to study the biochemical pathways involved. EMSA was performed to examine binding of NF-κB to NF-κB consensus sequence and PTP1B oligonucelotides in the cells treated with palmitate. Lentiviral PTP1B-shRNA was used to knockdown PTP1B in myotubes. The phosphorylation and protein levels of IRS-1 and Akt were detected by western blot. 0.5mM palmitate induced PTP1B promoter activity in fragment -1715/+59 by 50% (p<0.01). Palmitate increased NF-κB binding to both NF-κB consensus sequence and one NF-κB sequence (-920 to -935) in PTP1B promoter. Incubation of C2C12 cells with different concentrations of C2-ceramide enhanced PTP1B promoter activity dose-dependently. Inhibitors of de novo ceramide synthesis prevented palmitate-induced PTP1B promoter activity in myotubes. In addition, inhibitor of JNK pathway prevented ceramide-induced PTP1B promoter activity in myotubes. Knockdown of PTP1B also prevented ceramide-reduced IRS-1 and Akt phosphorylations in the myotubes. Exposure of the cells to PMA and calphostin C, an inhibitor of PKC, did not affect the activity of PTP1B promoter. Our data provide the evidence that the mechanism by which palmitate increased the expression of PTP1B seems to be through a mechanism involving the activation of ceramide-JNK and NF-κB pathways.

Estrogen receptor alpha gene polymorphisms are associated with type 2 diabetes and fasting glucose in male subjects.

The PvuII and XbaI polymorphisms of the estrogen receptor α (ER1) gene have been variably associated with type 2 diabetes (T2D) in several populations. However, this association has not been studied in Iranian subjects and we hypothesized that the ER1 variants might be associated with T2D and related metabolic traits in this population. The PvuII and XbaI genotypes were determined by PCR-RFLP in 377 normoglycemic controls and 155 T2D patients. Bonferroni correction was applied for the correction of multiple testing. No significant association was found between the allele and genotype frequencies of PvuII and XbaI variants with T2D in females. In a dominant model (PP vs. Pp+pp), the frequency of the Pp+pp genotype was higher in normoglycemic subjects compared to T2D patients [85.5% vs. 66.7%, OR 0.22 (0.08-0.55), P=0.001]. Four possible haplotypes were observed in the population, whereas haplotype TA had a higher frequency in male T2D subjects than the controls. Furthermore, non-diabetic male subjects carrying the genotype of PP had a higher fasting glucose levels than the individuals with the genotype of Pp+pp (P=0.013). Multivariate logistic regression analysis showed that PvuII polymorphism was the independent determinants of T2D in males [OR 4.37 (1.61-11.86), P=0.004]. No association was found between the XbaI polymorphism and diabetes in male group. Our results suggest that the ER1 polymorphisms might associate with T2D and fasting glucose among Iranian male subjects.

Study on the role of environmental parameters and HIF-1A gene polymorphism in coronary collateral formation among patients with ischemic heart disease.

OBJECTIVES: To evaluate the association between collateral formation and some environmental factors along with a polymorphism in HIF-1A gene in selected Iranian patients with CAD. DESIGN AND METHODS: Patients with ≥ 70% narrowing in at least one coronary vessel according to coronary angiography were enrolled. The patients' demographic, clinical and biochemical data were collected. The presence of C1772T polymorphisms within HIF-1A was analyzed using the polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP). RESULTS: There is no significant difference between the patients with and without collaterals according to the frequency of T allele or HIF-1A variants. The higher severity of coronary vessel obstruction was positive predictor of collateral formation (OR=1.026, 95%, CI: 1.02-0.04, p<0.001), whereas aging and cigarette smoking were negative predictors (OR=0.95, 95% CI: 0.91-0.99, p<0.05; OR=0.30, 95% CI: 0.11-0.79, p <0.05; respectively). CONCLUSIONS: The findings indicate not any significant association between collateral formation and polymorphic variants of HIF-1A and P582S substitution does not appear to influence the collateral formation in patients with myocardial ischemia.