目的观察不同浓度雷帕霉素对大鼠肾小球系膜细胞增殖及凋亡的影响,探讨其可能的作用机制。方法使用不同浓度雷帕霉素(1μg/L、2μg/L、4μg/L、8μg/L、16μg/L)处理大鼠肾小球系膜细胞,并设正常对照组。MTT法测不同浓度雷帕霉素干预24h、48h、72h后对细胞增殖的影响,并描记生长曲线。干预72h后,采用RT-PCR和Western印迹法分别检测各浓度雷帕霉素组细胞周期负调蛋白p27和p53的mRNA和蛋白表达变化;用流式细胞计量术检测各浓度雷帕霉素组细胞周期及凋亡率。结果小剂量雷帕霉素(1μg/L)对系膜细胞增殖即具有明显的抑制作用,停滞于G1期的细胞数明显增加,但对系膜细胞凋亡无明显影响。较大剂量雷帕霉素(8~16μg/L)能够明显增加肾小球系膜细胞凋亡。雷帕霉素能够增加肾小球系膜细胞p27、p53mRNA和蛋白表达,且呈剂量依赖性。结论雷帕霉素可能通过增加p27、p53表达抑制肾小球系膜细胞增殖和促进系膜细胞凋亡。
Objective To investigate the effect of different concentrations of rapamyein on the proliferation and apoptosis of glomerular mesangial cells (GMCs) and to investigate the mechanism. Methods GMCs were treated with different concentrations of rapamycin (1 νg/L, 2 μg/L, 4 μg/L, 8 μg/L, 16 μg/L). After treatment for 24 h, 48 h and 72 h, cell proliferation was assessed by MTT eolorimetric assay and the growth curve was traced. After treatment for 72 h, the cell cycle distribution and the apoptotic rate of GMCs in different concentrations of rapamycin were analyzed by flow cytometry. The effects of different concentrations of rapamycin on the mRNA and protein expression of p27 and p53 were detected by RT-PCR and Western blot respectively. Result The low dose of rapamycin (1 μg/L) could significantly inhibit the proliferation of GMCs and showed no effect on apoptosis. The high dose of rapamycin (8-16 μg/L) could significantly increase the apoptotic rate of GMCs. Rapamycin could increase the mRNA and protein expression of p27 and p53. Conclusion Rapamycin can inhibit GMCs proliferation and promote GMCs apoptosis by increasing the expression of p27 and p53.