miR-126促进脊髓损伤模型神经干细胞的生长增殖和分化

摘要

Objective:To observe the effect of miR-126 on the proliferation and differentiation of neural stem cells after spinal cord injury.Methods:T10 spinal cord contusion model was made by Allen's method.BMS score was used to evaluate motor function at different stages of spinal cord injury.H-E and Nissl staining were used to observe the changes of histopathology and Nissl body at injury site.RT-PCR was used to detect miR-126,nestin,and HOXA9 expression,while Western blotting was used to detect the expression of corresponding proteins.Results:The expression of miR-126 and nestin decreased at the early stage and increased at later stage.HOXA9 expression showed the opposite trend.Histological examination of early injury sites showed a large number of inflammatory cell infiltration and loss of Nissl body,and reduction of injury and gradual increase of Nissl body in the post-injury.BMS score increased with the increase of neurons to a certain extent.Conclusion:After spinal cord injury,miR-126 can promote the growth and proliferation of neural stem cells.At the same time,it can increase the differentiation of neural stem cells into neurons through the negative regulation of HOXA9 expression so as to promote the restoration of the movement function in mice.%目的:观察脊髓损伤后miR-126对在体神经干细胞生长增殖和分化的促进作用.方法:应用Allen法制作小鼠第10胸椎脊髓挫伤模型,在损伤后不同时期应用BMS评分对运动功能评估后,H-E染色、尼氏染色观察损伤部位组织病理学及尼氏体的变化.RT-PCR检测miR-126、nestin、HOXA9表达量,同时免疫印迹检测相应蛋白的表达.结果:miR-126、nestin早期表达量下降,后期有所升高.HOXA9表达量则出现与其相反趋势.组织学检测早期损伤部位大量炎症细胞浸润及尼氏体丢失,后期损伤程度减轻,尼氏体逐渐增多.BMS评分随神经元的增多而有一定程度的增高.结论:脊髓损伤后miR-126在促进神经干细胞生长增殖的同时,通过负向调节HOXA9表达提高神经干细胞向神经元的分化,从而促进小鼠运动功能修复.