PI3K-GLUT4 Signal Pathway Associated with Effects of EX-B3 Electroacupuncture on Hyperglycemia and Insulin Resistance of T2DM Rats

Abstract

Objectives.To explore electroacupuncture’s (EA’s) effects on fasting blood glucose (FBG) and insulin resistance of type 2 diabetic mellitus (T2DM) model rats and give a possible explanation for the effects.Method.It takes high fat diet and intraperitoneal injection of streptozotocin (STZ, 30 mg/kg) for model preparation. Model rats were randomly divided into T2DM Model group, EA weiwanxiashu (EX-B3) group, and sham EA group (n=12/group). EA (2 Hz continuous wave, 2 mA, 20 min/day, 6 days/week, 4 weeks) was applied as intervention. FBG, area under curve (AUC) of oral glucose tolerance test (OGTT), insulin resistance index (HOMA-IR), pancreatic B cell function index (HOMA-B), skeletal muscle phosphorylated phosphatidylinositol-3-kinase (PI3K), glucose transporter 4 (GLUT4), and membrane GLUT4 protein expression were measured.Results.EA weiwanxiashu (EX-B3) can greatly upregulate model rat’s significantly reduced skeletal muscle PI3K (Y607) and membrane GLUT4 protein expression (P<0.01), effectively reducing model rats’ FBG and AUC of OGTT (P<0.01). The effects are far superior to sham EA group.Conclusion.EA weiwanxiashu (EX-B3) can upregulate skeletal muscle phosphorylated PI3K protein expression, to stimulate membrane translocation of GLUT4 and thereby increase skeletal muscle glucose intake to treat T2DM.