ABSTRACT
Objective To study the effects of Apelin on glucose toxicity and islet cells PDX-1 protein expression.Methods The islet β cell line NIT-1 cells were incubated in the medium containing different glucose concentrations(normal glucose concentration group 5.6 mmol/L,high glucose concentration group 16.7 mmol/L,extremely high glucose concentration group 33.3 mmol/L) and +/-Apelin-36 respectively for 3 d.Then the basic insulin secretion amount of islet cells and their secretion amount after glucose stimulation were detected.The intracellular insulin content and the PDX-1 protein and mRNA expression were detected.Results Compared with the normal glucose group,the basic insulin secretion,secretion after stimulation and intracellular insulin in the high glucose group and extremely high glucose group were significantly decreased and PDX-1 protein expression was declined(P＜ 0.05);compared with non-adding Apelin group,the basic insulin secretion,secretion after stimulation and intracellular insulin in the adding Apelin high glucose group and extremely high glucose group were significantly decreased and PDX-1 protein expression was decreased(P＜0.05);the insulin level in islet cells of 6 groups was positively correlated with PDX-1 protein expression and had no correlation with PDX-1 mRNA expression.Conclusion Apelin may participate in the glucose toxic effect by decreasing PDX-1 protein expression,causes the decrease of insulin secretion,thus plays a role in the pathogenesis of diabetes.
ABSTRACT
The level of serum fibroblast growth factor-21 (FGF-21) in patients with type 2 diabetes mellitus complicated with non-alcoholic fatty liver disease (NAFLD) was determined by ELISA.The results showed that serum FGF-21 level in these patients was higher than that in type 2 diabetic patients [(266.55 ± 21.24 vs 220.32 ± 22.68) ng/L,P＜ 0.01].Serum FGF-21 levels in both groups were significantly higher than that in normal control group [(173.52 ± 16.18) ng/L,P＜0.01].Serum FGF-21 level was positively correlated with waist circumference,blood glucose,and triglyceride.FGF-21 may contribute to the development of NAFLD in the patients with type 2 diabetes mellitus.
ABSTRACT
The changes of serum apelin in patients with metabolic syndrome were investigated. The level of fasting serum apelin was determined by ELISA assay.The level of serum apelin was raised obviously in patients with metabolic syndrome(MS).Moreover,the level of serum apelin in patients with type 2 diabetes mellitus was higher than those in cases of MS with impaired glucose regulation and the group of subjects with overweight/obesity [ (475.8±37.3 vs 451.5±54.3 and 430.3±52.1 ) ng/L,P＜0.01 ].In a multiple step-wise regression analysis,In homeostasis model assessment of insulin resistance ( HOMA-IR),body mass index,and total cholesterol were independent factors of apelin.The increased serum apelin was closely related to metabolic abnormalities in metabolic syndrome.The increased insulin resistance might cause the raised level of serum apelin in patients with MS.