11 beta-hydroxysteroid dehydrogenase type 1 involved in tumor necrosis factor-a-induced insulin resistance / 中华老年医学杂志

ABSTRACT

Objective To evaluate the molecular mechanism of 11 beta-hydroxysteroid dehydrogenase type 1 (11 β-HSD1)in tumor necrosis factor-α (TNF-α) induced insulin resistance.Methods The optimal concentration and incubation time of TNF-α for treating HepG2 cells were selected.Real-time polymerase chain reaction(PCR)and Western blot analysis were used to explore the effect of TNFα on the mRNA and protein expression levels of 11β-HSD1,glucocorticoid receptor (GR),phosphoenolpyruvate carboxylase(PEPCK)and glucose 6-phosphatase(G6Pase).Glucose(GO) Assay Kit was used to determine the level of gluconeogenesis.Liver/Muscle glycogen assay kit,PAS/Glycogen Stain kit were used to detect glycogen synthesis.The expression of AKT/GSK pathway was analyzed by Western blot analysis.In addition,HepG2 cells were pre-treated with BVT2733,a specific inhibitor of 11β-HSD1,before exposure to TNFα The expression of AKT/GSK pathway,the level of gluconeogenesis and glycogen synthesis were analyzed.Results The expression of 11β-HSD1 was increased along with the increasing concentration of TNF-α,showing a dose-dependent effect.When HepG2 cells treated with the optimal dose of TNF-α 10 μg/L for 24 hours,the levels of GR,gluconeogenesis and gluconeogenesis-related genes PEPCK and G6Pase were increased,while conversely,the levels of phosphorylation of AKT and GSK,and glycogen synthesis were decreased.However,all the above effects induced by TNF-α in HepG2 cells were greatly reversed by BVT2733 pre treatment.Conclusions 11 β-HSD1 participates in TNF-α-induced insulin resistance in HepG2 cells,and BVT2733 could significantly improve insulin sensitivity.