骨髓基质干细胞对MPP^+制备的PC12细胞凋亡的影响

EFFECT OF BONE MARROW STROMAL CELLS ON PC12 APOPTOSIS INDUCED BY 1-METHYL-4-PHENYLPYRIDINE

目的探讨BMSCs分泌物对MPP+诱导的PC12细胞凋亡的保护作用。方法在体外培养、纯化BMSCs并收集其培养上清,流式细胞术分析PC12细胞的凋亡率;通过免疫细胞化学法和RT-PCR法检测PC12细胞bcl-2和TH在蛋白和mRNA水平的表达。结果BMSCs可在体外分离扩增,其表面抗原CD44阳性而CD45阴性,流式细胞术检测显示BMSCs上清液组加MPP+处理组(联合组)细胞凋亡率低于MPP+损害组;免疫细胞化学法和RT-PCR法显示联合组的bcl-2和TH蛋白和mRNA水平与MPP+损害组相比明显增加。结论BMSCs能分泌多种对退变多巴胺能神经元有保护作用的神经营养因子,因此BMSCs对MPP+诱导的PC12细胞凋亡有保护作用,其保护作用的强弱与BMSCs上清液浓度有关,其作用机制可能是通过上调bcl-2来实现的。

Objective To investige the effect of the secretory factors of mesenchymal stem cells （BMSCs） on the apoptosis in pheochromocytoma （PC12） cells induced by 1-methyl-4-phenyl pyrid iumion （MPP^＋） . Methods The BMSCs were cultured and purified, and the culture supematant was collected in vitro. Apoptosis ratio was analyzed by flow cytometry （FCM） ; The expressions of the protein and mRNA of bcl-2 and tyrosine hydroxylase （TH） were measured by using immunocytochemistry and RT-PCR techniques respectively. The difference between the groups was compared. Results BMSCs proliferated in vitro, and were positive for CD44 and negative for CD45 ; The results of FCM showed that the ratio of apoptosis in the group treated with secretory factors of BMSCs and MPP^＋ （combe group） decreased when compaed with the group treated with MPP^＋. The results of immunocytochemistry and RT-PCR showed that the content of protein and mRNA of TH and bcl-2 in the combo group was greater than in the injured group. Conclusion BMSCs can secrete neurotrophic factors beneficial to recessive dopamine （DA） neurons, so BMSCs may exert a protective effect against MPP^＋ induced apoptosis in PC12 cells. The effectiveness is dependent on the concentration. Its apoptosis inhibiting mechanism may be achieved by upregulating bcl-2.