Résumé
Objective: To study the effect of a-linolenic acid on insulin resistance and its mechanism concerning the insulin signal transduction,providing a theoratic basis for applying plant oil rich in a-linolenic acid in preventing and treating diabetes. Methods :The effect of a-linolenic acid on protein kinase B(PKB) signal transduction and expression of glucose transport protein 4(GLUT4) in rat skeletal muscles was detected by primary cell culture and Western blot techniques. Results:At the concentration of 0. 125-1. 0?mol/L, a-linolenic acid promoted the PKB phosphorylation, but didnot influence the expression of PKB. The expression of GLUT4 protein was dose-dependent and time-dependent. Adding PI3K inhibitor LY294002(15 ?mol/L) in a-linolenic acid cultured skeletal muscle cells made no significant difference in the level of PKB phosphorylation and GLUT4 protein. Conclusion:a-linolenic acid can improve the level of GLUT4 protein by promoting skeletal muscle PI3K/ PKB signal transduction,and increase the sensitivity of skeletal muscle on insulin, which can alleviate or avoid insulin resistance and glycometabolic disturbance.