目的 研究软脂酸对C2C12细胞过氧化物酶体增殖物激活受体γ辅激活子(PGC-1α)表达的影响,揭示丝裂原活化蛋白激酶(MAPKs)信号通路与PGC-1α表达的关系,寻找软脂酸诱导C2C12细胞PGC-1α表达变化的上游调节通路. 方法 检测软脂酸培养的C2C12细胞PGC-1α、细胞外信号调节激酶(ERK)、jnk氨基末端激酶(JNK)、p38丝裂原活化蛋白激酶(p38MAPK)及其磷酸化蛋白phosp-38MAPK(P-p38MAPK)的表达变化.寻找发生变化的MAPKs信号通路,用筛选到的p38MAPK抑制剂进行干预,分为对照(Con)组、软脂酸(Palmitate)组、p38MAPK抑制剂组和Palmitate+ p38MAPK抑制剂组,测定PGC-1α、p38MAPK总蛋白及其P-p38MAPK的表达. 结果 软脂酸培养的C2C12细胞PGC-1α蛋白表达下降,呈时间依赖性;ERK、phospho-ERK、JNK、phospho-JNK及p38MAPK表达无变化,P-p38MAPK表达升高.用p38MAPK抑制剂干预C2C12细胞,PGC-1α表达在Palmitate组最低,p38MAPK抑制剂组和Palmitate+ p38MAPK抑制剂组较Palmitate组升高,p38MAPK抑制剂组最高.结论 软脂酸诱导的PG C-1α表达下降可能由p38MAPK信号通路调控.%Objective To assay the expression of peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) in palmitic acid-incubated C2C12 cells,to reveal the relationship between mitogen-activated protein kinase (MAPKs) signaling pathway and PGC-1α expression,and to investigate the up-stream regulatory pathway of the PGC-1α in C2C12 cells.Metlods The expressions of PGC-1α,ERK,JNK,p38MAPK and phosphorylased proteins were detected in C2C12 cells incubated with palmitic acid to determine the expression changes of MAPKs signaling pathways.After being interfered with p38MAPK inhibitor,the expressions of PGC-1α,p38MAPK and P-p38MAPK were assayed.The cells were divided into four groups including control group,palmitic acid group,p38MAPK inhibitor group and palmitic acid plus p38MAPK inhibitor group.Results The protein expression of PGC-1α was significantly decreased in palmitic acid-incubated C2C12 cells in a time-dependent manner.There were no significant changes in the expressions of ERK,P-ERK,JNK,P-JNK and p38MAPK.However,the expression of P-p38MAPK increased.After being interfered with p38MAPK inhibitor,the expressions of PGC-1α were increased in p38MAPK inhibitor group and palmitic acid plus inhibitor p38MAPK group than those in palmitic acid group,with the highest in p38MAPK inhibitor group.Conclusion The down-expression of PGC-1α induced by palmitic acid may be regulated by p38MAPK.
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