SDF-1α促进原代培养大鼠星形胶质细胞增殖的作用

摘要

Aim To investigate the effects of stromal cell-derived factor-1α ( SDF-1α) on cell proliferation in primary cultured rat astrocytes and the possible mechanisms. Methods The primary cultured rat astr-cytes were treated with recombinant human SDF-1α at different concentrations, the cell proliferation was as-sessed by cell counting and 5-bromo-2’-deoxyuridine incorporation assay;intracellular calcium concentration was detected with calcium sensitive fluorescent probe;phorphorylation of extracellular regulated protein ki-nase1/2 ( ERK1/2 ) was determined by Western blot analysis;cell cycle transition was analyzed by flow cy-tometry analysis; mRNA expressions of cyclin A2 and cyclin B1 were determined by quantitative RT-PCR. Results Treatment of astrocytes with SDF-1α (5 -40 nmol·L-1 ) for 48 h induced significant cell prolifera-tion. SDF-1α at 20 nmol·L-1 increased the intracel-lular calcium concentration and the phosphorylation of ERK1/2. In addition, SDF-1α at 20 nmol·L-1 pro-moted the cell cycle transition from G0 to S and M pha-ses, and up-regulated the mRNA expressions of Cyclin A2 and Cyclin B1 . Conclusion SDF-1α significantly induces cell proliferation in primary cultured rat astro-cytes via enhancing calcium influx, ERK1/2 phospho-rylation, Cyclin expression and promoting cell cycle transition.%目的：研究间质细胞来源因子-1α( stromal cell-derived factor-1α,SDF-1α)对原代培养大鼠星形胶质细胞增殖的作用及其可能机制。方法以不同浓度的重组人SDF-1α作用于星形胶质细胞后,用细胞计数法和溴化去氧尿苷参入法检测细胞增殖；钙离子荧光探针检测细胞内钙离子浓度；West-ern blot法检测细胞外调节蛋白激酶( extracellular regulated protein kinase,ERK)1/2磷酸化水平；流式细胞仪检测细胞周期；定量RT-PCR法检测Cyclin A2和Cyclin B1的mRNA表达。结果不同浓度的SDF-1α(10-40 nmol·L-1)作用48 h可明显地促进星形胶质细胞的增殖。 SDF-1α(20 nmol ·L-1)处理可增加细胞内钙离子浓度,提高ERK1/2磷酸化水平；而且可促使细胞由G0期进入DNA合成期( S期)和有丝分裂期( M期),上调Cyclin A2和 Cyclin B1的 mRNA表达。结论 SDF-1α可明显诱导离体培养大鼠星形胶质细胞增殖,其机制可能是促进钙离子内流,磷酸化ERK1/2,上调Cyclin表达而促进细胞进入DNA合成期和分裂期。