Effect of Electrical Stimulation at Different Time on Mitochondrial Function of C2C12 Myotubes

Abstract

Objective: To study the effect of different time of electrical stimulation on mitochondrial function of C2C12 myotubes, and further explore its molecular mechanism.Methods: An electrical stimulation was given 7 days after C2C12 myotubess differentiation, of which intensity was 30 ms, 3Hz, and the stimulation time was 60 mins, 120 mins, and 180 mins, respectively. A total of four experimental 4 groups, including control group (Con), 60 mins group (E60), 120 mins (E120) and 180 mins (E180). Microscope was used to observe the muscular myotubes form; Kits were to detect MDA, SOD and ROS; Western blot was used to detect the expression of autophagy proteins and mechanism proteins, including PGC1, p-ULK, SIRT1 and SIRT3; Flow cytometry technology was used to detect muscle mitochondrial membrane potential.Results: There was no significant difference of C2C12 myotubes form after different electrical stimulation. Compared with the control group, E60 had no significant difference of mitochondrial membrane potential (p>0.05); but MDA, ROS, SIRT3 increased significantly (p<0.05), p-ULK and PGC1 increased significantly (p<0.01), SIRT1 decreased significantly (p<0.05). In E120, MDA, ROS, SIRT3 and PGC1 increased significantly (p<0.01), SOD and mitochondrial membrane potential decreased significantly (p<0.05). In E180, MDA and ROS increased significantly (p<0.01), SOD and mitochondrial membrane potential decreased significantly (p<0.01).Conclusion: Moderate electrical stimulation (60 and 120 mins) can significantly activate oxidative stress, and further promote SIRT3, PGC1 and p-ULK expression, and further promote the mitochondrial membrane potential, while excessive stimulation (180 mins) has the opposite effects.