牙髓干细胞共培养改善1-甲基-4-苯基吡啶离子诱导的神经元凋亡

Co-culture with dental stem cells ameliorates neuronal apoptosis induced by 1-methyl-4-phenyl pyridinium

背景:如何利用牙髓干细胞改善神经损伤对于神经退行性疾病的临床治疗具有重要的意义。目的:探讨牙髓干细胞共培养对1-甲基-4-苯基吡啶离子(1-methyl-4-phenyl pyridinium,MPP^+)诱导的神经元凋亡的影响。方法:分离培养人牙髓干细胞,进行形态观察和成脂成骨诱导分化能力鉴定;分离中脑神经元细胞,利用Transwell小室进行牙髓干细胞和神经元共培养,然后加入MPP^+干预48 h,通过Tunel染色和western blot法检测牙髓干细胞对MPP^+诱导的神经元凋亡的影响。结果与结论:(1)牙髓干细胞形态呈梭形,且能够成功向成脂成骨方向诱导分化;(2)牙髓干细胞和神经元细胞共培养后,减轻了MPP^+诱导的神经元凋亡;(3)MPP^+处理后降低了Bcl-2的表达,促进了Bax和cleaved caspase3的表达,而在牙髓干细胞共培养条件下,抗凋亡蛋白Bcl-2表达明显上升,促凋亡蛋白Bax和cleaved caspase3表达明显下降;(4)结果表明,人牙髓干细胞可以保护或修复体外MPP^+诱导的神经元损伤,该保护作用可能是通过人牙髓干细胞的旁分泌作用来实现的。

BACKGROUND： How to ameliorate neural injury by dental pulp stem cells is of clinical benefit for neurodegenerative diseases. OBJECTIVE： To investigate the effect of co-culture with dental pulp stem cells（DPSCs） on 1-methyl-4-phenyl pyridinium（MPP^＋）-induced apoptosis of neurons. METHODS： Human DPSCs were isolated and identified by morphological observation, adipogenic and osteogenic differentiation. Rat midbrain neurons were isolated and co-cultured with DPSCs by Transwell. After treatment with MPP^＋ for 48 hours, the neurons were observed in morphology, and the effect of DPSCs on neuronal apoptosis induced by MPP^＋ was detected by western blot and TUNEL staining. RESULTS AND CONCLUSION： DPSCs were spindle-like cells capable of differentiating into adipogenesis and osteogenesis. The apoptosis of neurons induced by MPP^＋ were alleviated via co-culture with DPSCs. Further detection by western blot showed that the neurons treated with MPP^＋ reduced the expression of Bcl-2 and promoted the expression of Bax and cleaved caspase 3; however, the changes in the expression of these proteins were reduced under the co-culture system of DPSCs. All the above results reveal that DPSCs may repair or prevent neuronal injury induced by MPP^＋ through paracrine actions.