骨髓间充质干细胞对冈田酸致神经细胞损伤的修复作用

Role of bone marrow mesenchymal stem cells in repair of neural cell injury induced by okadaic acid

目的观察人骨髓间充质干细胞对冈田酸(OA)损伤的神经细胞是否具有修复作用。方法应用冈田酸损伤神经母细胞瘤细胞系SH-SY5Y细胞,建立阿尔茨海默病体外模型。将细胞分成正常组、损伤组和治疗组,损伤组用20nmol/L冈田酸损伤24h,治疗组在损伤24h后加入骨髓间充质干细胞的条件培养基治疗24h。采用CCK-8法检测各组细胞活力,免疫荧光染色微管微丝测定细胞树突长度和荧光面积,Western blotting检测磷酸化Tau蛋白和总Tau蛋白含量。结果冈田酸能损伤SH-SY5Y细胞,使其胞体皱缩、塌陷,出现空泡,树突缩短、断裂,微管微丝排列紊乱,而骨髓间充质干细胞条件培养基可使SH-SY5Y细胞胞体变得圆润,树突重新恢复变长,微管、微丝致密规则,荧光变强;并且能有效降低冈田酸诱导的Tau蛋白过度磷酸化水平。结论骨髓间充质干细胞对冈田酸损伤的神经细胞具有明显的修复作用。

Objective To study whether the human bone marrow mesenchymal stem cells （HBMSCs） can repair damaged neural cells induced by okadaic acid （OA）. Methods Neuroblastoma cell line SH-SYSY cells were used to incubate with 20nmol/L okadaic acid for 24h, establishing Mzheimer＇s Disease cell model; Three groups were set up： normal group, okadaic acid -damaged （OA-damaged） group, hBMSCs -treatment group. The cells were injured for 24h with 20nmol/L OA in OA-damaged group, and treated with conditioned medium obtaining hBMSCs for 24h after 24h OA injury in the treatment group. Then CCK-8 was used for detecting cell vitality, immune fluorescence dyed microtubules and microfilaments for determining the dendritic cell length and fluorescence intensity, in addition, Western blotting for analyzing the protein level of phosphorylated tau and total tau proteins. Results Okadaic acid damaged SH-SYSY cells, contributed to shrinkage, collapse, cavitation of the SH-SYSY cell body, dendritic shortening and fracture, and irregular arrangement of microtubule microfilaments; while BMSCs conditioned medium made SHSYSY cell body become round and longer, dendrites restored, and microtubules and microfilaments arranged regularly, fluorescence intensity enhanced. Meanwhile, it also down-regulated the level of OA-induced tau phosphorylation. Conclusion hBMSCs have repair effects on the neural cell damage induced by okadaic acid.