Vitamin E protects the insulin sensitivity and redox balance in rat L6 muscle cells exposed to oxidative stress

Background: The effect of reactive oxygen species (ROS) on insulin action is unclear. This study was carried out to explore the effect of prolonged low grade oxidative stress and vitamin E treatment oil cultured rat L6 muscle cells. Methods: L6 myotubes were incubated with vitamin E for 18 It and treated with H2O2 generating system for 12 h. Insulin stimulated glucose uptake, total antioxidant capacity and reduced glutathione concentration were measured. Results: There was a marked decrease in insulin stimulated glucose transport in L6 cells exposed to H2O2 generating system. Pretreatment with vitamin E allenuates the effect of H2O2 on insulin action. Treatment with H2O2 caused a significant reduction in the levels of reduced glutathione and total antioxidant capacity, these alterations were reversed by vitamin E pretreatment. Vitamin E per se had no effect on insulin stimulated glucose transport in cells not exposed to oxidative stress. Conclusion: In conclusion, our observations indicate that vitamin E improves the free radical defense system potential and prevents oxidative stress induced insulin resistance in rat L6 muscle cells. (c) 2005 Elsevier B.V. All rights reserved.