外源性瘦素通过丝裂素活化蛋白激酶抑制猪骨骼肌成肌细胞分化

Exogenous Leptin Inhibits Differentiation via MAPK in Swine Skeletal Myoblasts

摘要:

研究瘦素(leptin)对猪骨骼肌成肌细胞分化的影响, 并探讨其可能的作用机制。原代培养猪骨骼肌成肌细胞, 通过倒置显微镜定性观察细胞分化的形态学变化; 肌酸激酶(CK)活性测定法定量分析成肌细胞分化程度; 细胞免疫化学方法分析myogenin的表达情况; 免疫印迹技术(Western Blot)检测丝裂素活化蛋白激酶(mitogen activated protein kinase, MAPK)的表达变化。结果显示, 在猪骨骼肌成肌细胞分化过程中, 外源性leptin减少细胞核融合和肌管形成, 呈浓度和时间依赖性地显著降低CK活性( P < 0.05), 并显著抑制myogenin和MAPK的蛋白表达( P < 0.05)。以上结果说明, leptin抑制猪骨骼肌成肌细胞分化, 并且这种作用可能是通过激活MAPK 信号转导通路实现的。研究结果显示, leptin在骨骼肌成肌细胞分化过程中可能具有重要作用。

Abstract:

We determined whether body-weight regulator, leptin, could influence differentiation of swine skeletal myoblasts. Myoblast occured in non-leptin and leptin formed in different concentrations (10~1000 ng/mL) for various duration (12~60 h). The morphologic assay demonstrated that leptin significantly decreased the formation of myotubes and myogenic index. In addition, biochemical analysis showed that leptin inhibited Creatine Kinase (CK) activity, expressions of myogenin and mitogen activated protein kinase (MAPK). As conclusion, exogenous leptin could inhibit differentiation via MAPK in swine skeletal myoblasts and this suggests that leptin be an important mediator in the regulation of muscle-cell differentiation.