Effects of the Electrical Stimulation on the Free Radicals and Nrf2/ARE Signaling Pathway in C2C12 Cells of Skeletal Muscles / 中国运动医学杂志

ABSTRACT

Objective To discuss the effect of the electric stimulation on the free radicals and Nrf2 signaling pathway in skeletal muscle myoblasts(C2C12) of mice.Methods After 6 days of differentiation,skeletal muscle myoblasts(C2C12) cells of mice were randomly divided into a control group and an electrical stimulation group.The control group was not stimulated,while the electrical group was stimulated 30,45,60,75,90,120 and 150 minutes respectively with the electrical parameter as 20 ms,45 V and 5 Hz.The reactive oxygen species(ROS),glutathione peroxidase(GSH-Px) and nuclear factor E2 related factor 2(Nrf2) protein expression in C2C12 muscle tubes were determined.Results Compared with the control group,the amount of ROS produced in the C2C12 muscle tube increased significantly in the stimulation group(P＜0.05),except those stimulated for 30 and 150 minutes,with greatest increase for those stimulated for 60 and 120 minutes(P＜0.01).Compared with the control group,the activity of GSH-Px and the expression of Nrf2 nuclear protein increased significantly in all the stimula tion group(P＜0.05),except those stimulated for 30 minutes and with the greatest increase for those stimulated for 75 and 150 minutes(P＜0.01).Conclusion The electrical stimulation of 45 V,20 ms and 5 Hz can cause oxidative stress in the C2C12 muscle tube.Based on the variation of ROS production with the time of electric stimulation,it is found that only when ROS increases to a certain amount,can it activate the Nrf2 signaling system and related genes to make the GSH-Px play an antioxidant role.However,with the increase of stimulation time,the anti-oxidative ability decreases slightly,and then it continues to maintain its high level.