Apelin促进小鼠成骨细胞MC3T3-E1的增殖

Proliferation of Mouse Osteoblastic Cell Line MC3T3-E1 Stimulated by Apelin

目的观察Apelin对小鼠成骨细胞MC3T3-E1增殖和分化的作用,探讨其可能的作用机制。方法 RT-PCR检测MC3T3-E1细胞APJ(Apelin受体)的表达、Western blot、ELISA、放射免疫法和[3H]TdR-掺入法检测MAPKs和Akt的激活,以及MC3T3-E1细胞的增殖和分化指标;用PI3-K抑制剂LY294002,AKT抑制剂HIMO和JNK抑制剂SP600125预处理以观察Apelin影响MC3T3-E1细胞增殖的信号转导机制。结果 MC3T3-E1细胞表达APJ;Apelin对MC3T3-E1细胞碱性磷酸酶(alkali phosphatase,ALP)活性、骨钙素(osteocalcin,OC)和Ⅰ型胶原(type Ⅰ collagen)的分泌及Runx2蛋白的表达无影响;Apelin促进MC3T3-E1细胞增殖;Apelin诱导JNK和PI3-K/AKT的磷酸化;PI3-K抑制剂LY294002,AKT抑制剂HIMO和JNK抑制剂SP600125均可以抑制Apelin对MC3T3-E1细胞的促增殖作用。结论 MC3T3-E1细胞表达APJ;Apelin通过JNK和PI3-K信号转导通路促进MC3T3-E1细胞增殖,但对其分化无影响。

Objective To observe the effect of apelin on the proliferation and differentiation of mouse osteoblastic cell line MC3T3-E1,and to explore its possible mechanisms. Methods RT-PCR was used to detect APJ（apelin receptor） expression in MC3T3-E1 cells.Western blot,ELISA,radioimmunoassay,and TdR incorporation were used to detect the indices of the proliferation and differentiation of MC3T3-E1 cells.Furthermore,PI3-K inhibitor LY294002,AKT inhibitor HIMO and JNK inhibitor SP600125 were used to explore the mechanism of signal transduction of apelin on the proliferation of MC3T3-E1 cells. Results MC3T3-E1 cells expressed APJ.Apelin had no effect on ALP activity,type I collagen and osteocalcin secretion,and Runx2 expression in MC3T3-E1 cells.Apelin stimulated proliferation of MC3T3-E1 cells.Apelin activated JNK and PI3K/AKT signaling pathways in MC3T3-E1 cells.LY294002,HIMO and SP600125 inhibited the effect of apelin on proliferation of MC3T3-E1 cells. Conclusions MC3T3-E1 cells express APJ.Apelin stimulates proliferation of MC3T3-E1 cells through JNK and PI3-K/Akt signaling pathways,but has no effect on differentiation of MC3T3-E1 cells.