Erk和p38信号转导通路对大鼠肌源性干细胞内结缔组织生长因子表达的调控作用

Regulative effects of Erk and p38 signal pathway on expression of CTGF in rat muscle-derived stem cells

目的探讨肌源性干细胞（muscle derived stem cells，MDSC）受转化生长因子田（transforming growth factor-β1，TGF-β1）刺激产生结缔组织生长因子（connective tissue growth factor，CTGF）的过程中，Erk信号转导通路和p38信号转导通路是否发挥作用。方法采用细胞差速贴壁法，从新生大鼠骨骼肌中分离提取肌源性干细胞，进行细胞表型鉴定后传代培养。实验设空白组、对照组和实验组共8组：空白组，添加液为基础培养基；对照组，基础培养基中加TGF-β1；PD98059实验组，分别用20、40、80μM的PD98059预处理；SB203580实验组，分别用0．2,0．5、1．0μM的SB203580预处理。用RealTime-PCR和Western Blot分别检测细胞中CTGFmRNA和蛋白质的水平。结果空白组、对照组和PID8059实验组间CrGFmRNA和蛋白质的相对表达量差异均有统计学意义（p〈0．05），对照组和SB203580实验组间差异均无统计学意义（P〉0．05）。结论TGF—β1诱导MDSC产生CTGF的过程中，存在着Erk信号转导途径，不存在p38信号转导途径。

Objective To investigate the role of Erk and p38 pathway in the process of CTGF expression in TGF-β1-induced muscle-derived stem ceils （MDSCs）. Methods MDSCs were isolated from the skeletal muscle of neonatal rats. After phenotyping, these MDSCs were cultured under 8 conditions according to group assignment： normal control group （MDSCs ＋ basic culture）, negative control group （MDSCs ＋ basic culture ＋ TGF-131）, experimental group 1-3 （MDSCs pretreated with 20, 40 and 80μM of PD98059 respectively ＋ basic culture ＋ TGF-β1）, experimental group 4-6 （ MI）SCs pretreated with 0.2, 0.5 and 1.0 μM of SB203580 ＋ basic culture ＋ TGF-β1 ）. After 48 hours, the MDSCs CTGF mRNA expression and protein level were quantified with Real Time-PCR and Western Blot. Results There were statistically significant differences of CTGF expression levels among normal control group, negative control group and experimental group 1-3 （ P 〈 0.05）. There was no significant difference in CTGF expression between the negative control group and experimental group 4-6 （ P 〉 0. 05）. Conclusion Erk plays a role in TGF-β1-CrGF signal transduction of rat MDSCs, whereas p38 does not.