Glucose uptake through translocation and activation of GLUT4 in PI3K/Akt signaling pathway by asiatic acid in diabetic rats

Abstract

In this study, we examined the in vivo effect and the mechanism of asiatic acid (AA) on glucose uptake in an insulin target skeletal muscle. Diabetic rats showed significantly increased levels of plasma glucose, thiobarbituric acid reactive substances, and lipid hydroperoxides, decreased levels of insulin and antioxidants, and impairment in insulin-signaling proteins such as insulin receptor (IR), insulin receptor substrate (IRS)-1/2, phosphoinositide 3-kinase (PI3K), Akt, and glucose transporter 4 (GLUT4) proteins. Oral treatment with AA (20 mg/kg body weight) showed near-normalized levels of plasma glucose, lipid peroxidation products, and antioxidants and improved insulin, IR, IRS-1/2, PI3K, Akt, and GLUT4 proteins. These findings suggest that AA improves glucose response by increasing GLUT4 in skeletal muscle through Akt and antioxidant defense in plasma and it also improves glucose homeostasis.