Leptin promotes proliferation and inhibits differentiation in porcine skeletal myoblasts.

Leptin, a major regulator of body weight, was recently suggested to play a role in myoblasts. We conducted an experiment to determine whether leptin can influence the proliferation and differentiation of porcine skeletal myoblasts. Myoblasts occurred in non-leptin and leptin forms in various concentrations for various periods of cell states. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and flow cytometry assays demonstrated that leptin significantly promoted myoblast proliferation and increased cell accumulation in the S + G2/M phase, in a dose-dependent manner. Furthermore, in morphologic experiments, the formation of myotubes and the myogenic index was markedly reduced by leptin. In addition, biochemical analysis showed that leptin decreased creatine kinase (CK) activity and the amount of myogenin and myosin heavy chain (MyHC) protein. Taking all this together, our study indicated that exogenous leptin promoted proliferation but inhibited differentiation in porcine skeletal myoblasts, suggesting that leptin might be an important mediator in the regulation of the growth and development of muscle cells.