Vibration exercise decreases insulin resistance and modulates the insulin signaling pathway in a type 2 diabetic rat model.

Vibration exercise (VE) is a new type of physical training, but little is known about its effects on insulin resistance at the molecular level. A Sprague-Dawley rat model of type 2 diabetes with insulin resistance was induced with a high-fat diet and low-dose streptozotocin. Animals were then subjected to 8 wk of VE consisting of placing the rats on a vibration stand bracket (8 cm × 8 cm × 20 cm) with a maximum vertical vibration displacement of 52 mm for 15 min twice a day, 6 d each week. Various metabolic markers and the phosphorylation and expression of proteins within the PI3K/AKT insulin signaling pathway were assessed. The high-fat diet and low-dose streptozotocin increased food intake, body weight, and levels of blood glucose, triglycerides, total cholesterol, and free fatty acids, while Kitt rate, 2-deoxyglucose uptake, and glycogen levels were decreased. These effects were ameliorated in animals receiving VE. VE treatment activated the PI3K/AKT insulin-signaling pathway, and also increased the expression of GLUT4. In conclusion, VE improved the metabolic issues associated with the diabetic state by suppressing the reduction of IRS1, AKT2, and GLUT4 in the diabetic condition, indicating that VE could be used as a therapeutic intervention for insulin resistance and type 2 diabetes.