目的 探讨益气活血通络方对脊髓型颈椎病模型大鼠微小RNA-126a-5p(miR-126a-5p)及血管内皮生长因子(VEGF)信号通路的影响.方法 30只健康雄性SD大鼠按照随机数字表法均分为假手术组、模型组和中药组.模型组、中药组均制备脊髓型颈椎病模型.中药组给予益气活血通络方灌胃,假手术组、模型组给予生理盐水灌胃,均为12周.各组干预结束后进行大鼠行为学测试,测定机械性刺激阈值和热刺激回缩时间.处死大鼠,HE染色观察各组椎间盘软骨终板结构的差异.TUNEL染色观察大鼠椎间盘纤维环细胞变化.实时荧光定量聚合酶链式反应检测大鼠椎间盘纤维环组织miR-126a-5p和VEGF mRNA.采用Western blot法检测大鼠椎间盘纤维环组织VEGF蛋白表达.结果 与假手术组比较,模型组大鼠椎间盘血管芽数目减少,大鼠椎间盘纤维环细胞破坏明显、大量凋亡且细胞密度降低;模型组和中药组机械性刺激阈值降低,热刺激回缩时间缩短,miR-126a-5p水平降低,VEGF mRNA和蛋白表达水平升高(P<0.05).与模型组比较,中药组大鼠椎间盘血管芽数目增加,大鼠椎间盘纤维环细胞破坏减轻,大鼠椎间盘纤维环细胞凋亡减少且细胞密度增加,机械性刺激阈值升高,热刺激回缩时间延长,miR-126a-5p水平增加,VEGF mRNA和蛋白表达水平降低(P<0.05).结论 益气活血通络方治疗脊髓型颈椎病的机制可能与上调miR-126a-5p、下调VEGF表达有关.
Objective To investigate the effect of Yiqi Huoxue Tongluo Decoction on microRNA-126a-5p(miR-126a-5p)and vascular endothelial growth factor(VEGF)signaling pathway in cervical spondylotic myelopathy model rats.Methods Thirty healthy male SD rats were divided into the sham operation group,the model group and the traditional Chinese medicine(TCM)group by random number table method.Cervical spondylotic myelopathy models were prepared in the model group and the TCM group.The TCM group was given intragastric administration of Yiqi Huoxue Tongluo Decoction,while the sham operation group and the model group were given intragastric administration of normal saline for 12 weeks.After intervention,the threshold of mechanical stimulation and retraction time of thermal stimulation in each group were measured by behavior tests.Rats were sacrificed to collect intervertebral disc tissue for hematoxylin-eosin(HE)staining and observe the number of vascular buds in intervertebral disc.Rat intervertebral disc annulus fibrosus cells were subjected to terminal dexynucleotidyl transferase-mediated dUTP nick end labeling(TUNEL)staining.The miR-126a-5p and VEGF mRNA of rat intervertebral disc tissue were detected by real-time fluorescence quantitative polymerase chain reaction(RT-PCR).The expression of VEGF protein of rat intervertebral disc tissue was detected by Western blot assay.Results Compared with the sham operation group,the number of vascular buds in intervertebral disc was decreased in the model group and the TCM group.The cell destruction of intervertebral disc annulus was obvious in rats,and apoptosis was high and cell density decreased.Mechanical stimulation threshold decreased,and mechanical stimulation threshold decreased.The level of miR-126a-5p was decreased,and the expression levels of VEGF mRNA and protein were increased.Compared with the model group,the number of vascular buds in intervertebral disc was increased in the TCM group.The destruction of intervertebral disc annulus cells was alleviated in rats.The apoptosis of annulus fibrosus cells in intervertebral disc decreased and cell density increased.The threshold of mechanical stimulation increased,and the retraction time of thermal stimulation was prolonged.The level of miR-126a-5p increased,and the expression levels of VEGF mRNA and protein decreased(P<0.05).Conclusion The mechanism of Yiqi Huoxue Tongluo Decoction in the treatment of cervical spondylotic myelopathy may be related to the up-regulation of miR-126a-5p expression and the down-regulation of VEGF expression.