【摘要】 研究肿瘤坏死因子α(TNFα-)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;生肌指数和肌酸激酶(CK)活性定量分析成肌细胞分化程度;细胞免疫化学法分析肌球蛋白重链(MyHC)的蛋白表达情况;采用特异性抑制剂探讨TNFα-可能的作用信号途径。结果显示:在猪骨骼肌成肌细胞分化过程中,外源性TNFα-减少细胞核融合和肌管形成;浓度依赖性地显著降低生肌指数和CK活性(P<0.05);并显著抑制MyHC蛋白表达(P<0.05);TNFα-+SB205380或TNFα-+PD98059处理组与TNFα-处理组相比,其CK活性和myogenin蛋白表达显著回升(P<0.05)。结果表明:TNFα-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细胞外信号调节激酶(ERK)和促分裂原活化蛋白激酶(MAPK)信号转导通路实现的。研究结果暗示TNFα-在猪骨骼肌成肌细胞分化过程中可能具有重要作用。更多还原

【Abstract】 To investigate the effects of Tumor Necrosis Factor alpha(TNF-α) on the differentiation of porcine skeletal myoblasts,and elucidate its potential mechanism,a study was designed to determine whether leptin influences the effects of TNF-α.Beginning with the primary control of porcine skeletal myoblasts,the morphologic change of celluar differentiation was observed using the inverted microscope.Myogenic index and creatine kinase(CK) were used to analyze differentiation of skeletal myoblasts in quantitative assay.Cell immunochemistry was used to measure the protein expression of myogenin and myosin heavy chain(MyHC), the possible actuating signal channel of TNF-α was investigated by adopting specific inhibitors.Exogenous TNF-α decreased the fusion of cell nucleus and myotube formation during differentiation of porcine skeletal my oblasts,concentration dependent decreased Myogenic index and CK(P<0.05),and significantly inhibited the expression of MyHC protein(P<0.05),In comparison with TNF-α+ SB205380 or TNF-α+PD98059,CK activity and myogenin mRNA remarkably increased by TNF-α treatment(P<0.05).These indicate that TNF-α inhibits differentiation in porcine skeletal myoblasts via extracellular regulated kinase(ERK) and mitogen-activated protein kinase(MAPK),TNF-α might play a potentially important role in differentiation in porcine skeletal myoblasts .更多还原