电针干预对大鼠脊髓损伤后miR-124-3p及Bcl-2、Bax表达的影响

Effects of electroacupuncture intervention on the expression of miR-124-3p,Bcl-2 and Bax after spinal cord injury in rats

目的:通过观察miR-124-3p及Bcl-2、Bax蛋白的表达,探讨电针治疗对脊髓损伤(SCI)大鼠神经功能恢复的机制。方法:将SD大鼠随机分为假手术组、模型组、电针组。假手术组行椎板切除术,其余各组通过改良版Allen’s打击法建立SCI大鼠模型。造模成功后6 h起,电针组予T9~T11夹脊穴、大椎穴以及双侧足三里穴电针治疗,假手术组和模型组不予任何处理。在术后第1、第3、第7天采用Basso-Beattie-Bresnahan(BBB)评分观察各组大鼠后肢运动功能,并于术后第7天进行取材,苏木精—伊红(HE)染色法观察脊髓组织神经元细胞的病理形态学改变,RT-qPCR法检测脊髓组织中miR-124-3p的表达情况,Western blotting检测脊髓组织中凋亡蛋白B淋巴细胞瘤-2(Bcl-2)、B淋巴细胞瘤-2相关X蛋白(Bax)的表达量。结果:与假手术组相比,术后第7天模型组大鼠BBB评分降低,神经元数量减少,脊髓组织中Bax的表达水平升高,miR-124-3p、Bcl-2的表达水平下降(P<0.05);与模型组相比,术后第7天电针组大鼠BBB评分提高,神经元数量增多,组织中Bax的表达水平降低,miR-124-3p、Bcl-2的表达水平升高(P<0.05)。结论:电针治疗可以促进SCI后大鼠神经功能的恢复,其机制可能与调控miR-124-3p及Bcl-2、Bax的表达有关。

Objective:To investigate the mechanism of neurological recovery in the electroacupuncture treatment of rats with spinal cord injury(SCI)by observing the expression of miR-124-3p,Bcl-2 and Bax.Methods:Sprague-Dawley(SD)rats were randomly divided into sham-operated group,model group and electroacupuncture group.The sham-operated group underwent laminectomy,and the remaining groups were established by a modified version of Allen's percussion method for SCI rat model.From 6 h after successful modeling,the electroacupuncture group was treated with electro-acupuncture at the chest jiaji points 9 to 11,the dazhui point and both foot sanli points.The motor function of the hind limbs of each group was observed by Basso-Beattie-Bresnahan(BBB)score on the 1st,3rd and 7th postoperative days.A sampling was performed on the 7th postoperative day,and the pathomorphological changes of neuronal cells in spinal cord tissues were observed by hematoxylin-eosin(HE)staining.The expression of miR-124-3p in spinal cord tissues was detected by RT-qPCR,and the expression of apoptotic protein B-cell lymphoma-2(Bcl-2)and B lymphocytoma-2-associated X protein(Bax)in spinal cord tissues was detected by western-blotting.Results:Compared with the sham-operated group,rats in the model group had lower BBB scores,decreased number of neurons,increased expression levels of Bax in spinal cord tissues and decreased expression levels of miR-124-3p and Bcl-2 on postoperative day 7(P<0.05).Compared with the model group,rats in the electroacupuncture group had higher BBB scores,increased number of neurons,decreased expression levels of Bax and increased expression levels of miR-124-3p and Bcl-2 in tissue on postoperative day 7(P<0.05).Conclusion:Electroacupuncture treatment can promote the recovery of neurological function in rats after SCI,and the mechanism may be related to the regulation of the expression of miR-124-3p,Bcl-2 and Bax.