夹脊电针对急性脊髓损伤大鼠炎症因子表达的影响

Effect of Jiaji Electro-Acupuncture on Expressions of Inflammatory Cytokines in Rats with Acute SCI

目的:探讨夹脊电针对脊髓损伤(SCI)大鼠炎症因子表达的影响。方法:随机将72只SD大鼠按照实验设计分为:假手术组(Sham组)、模型组(Model组)和夹脊电针组(EA组),再分别按照1 d、3 d、7 d和21 d治疗时间点分为4个亚组,每个亚组各6只。采用Allen’s法造模型,EA组选取T_(9)和T_(11)两对夹脊穴行电针治疗,Sham组和Model组的大鼠仅捆绑不予任何处置,各时间点治疗后取材,采用HE染色法观察大鼠脊髓组织病理形态学变化,采用免疫组化法(IHC法)测量大鼠脊髓组织IL-1β、IL-18和NLRP3表达量的变化,采用蛋白印迹法(Western blot法)测量NLRP3蛋白的表达情况。结果:HE染色结果:Sham组脊髓组织切片各结构形态完整,神经元无胞体肿胀,未观察到明显出血区域;与Sham组比较,Model组在不同时间点可见损伤脊髓组织区域不同程度神经元异常,灰白质间隙模糊不可见,病态造血面积、胞浆空泡变性及炎性细胞浸润多于EA组;与Model组大鼠相比,EA组大鼠在不同时间点脊髓炎症损伤程度较轻,有好转趋势。IHC法检测IL-1β、IL-18和NLRP3阳性细胞的表达结果:与Sham比较,Model组在各时间点的IL-1β、IL-18和NLRP3表达明显升高,差异有统计学意义(P<0.05);而与Model组比较,EA组脊髓组织在3 d、7 d、21 d的IL-1β、IL-18和NLRP3表达均下降,差异有统计学意义(P<0.05)。Western blot法检测NLRP3蛋白表达结果:Sham组中NLRP3的含量极低,与Sham组比较,Model组和EA组大鼠脊髓组织NLRP3蛋白表达在1 d、3 d、7 d及21 d各个时间点显著升高,差异有统计学意义(P<0.05);与Model组大鼠相比,EA组大鼠在进行夹脊电针治疗后,其脊髓组织NLRP3表达水平在3 d、7 d以及21 d后均显著下降,差异具有统计学意义(P<0.05)。结论:夹脊电针可有效减轻SCI后炎症反应,作用机制可能与下调SCI后大鼠脊髓组织NLRP3、IL-18和IL-1β的表达有关。

Objective:To investigate the effect of Jiaji electro-acupuncture on the expressions of inflammatory cytokines in the rats with acute spinal cord injury(SCI).Methods:72 SD rats were randomly divided into the sham operation group,the model group and the Jiaji EA group,and each group was sub-divided into four subgroups according to 1 d,3 d,7 d and 21 d different time points,with 6 rats in each subgroup.The Allen’s method was used to prepare SCI model.Two pairs of Jiaji points,T_(9) and T_(11) were selected in the EA group.The sham operation group and the model group were fixed by the same method without any other intervention.The injured spinal cord tissue was collected at 1d,3d,7d and 21d after the treatment respectively.The pathological morphological changes of spinal cord were observed by HE staining method.The expressions of IL-1β,IL-18 and NLRP3 in spinal cord were detected by IHC method in each group.The protein expression of NLRP3 was measured by Western blot method.Results:In terms of HE staining results,the spinal cord tissue sections of the sham operation group showed complete structure and normal morphology,no cell body swelling of neurons and no obvious bleeding area.Compared to those in the sham operation group,abnormal neurons with different degrees were observed in the spinal cord tissues at different time points,and gray matter gap was blurred even invisible in the model group;more morbid hematopoietic area,vacuolar degeneration of cytoplasm and inflammatory cell infiltration were seen in the model group than those in the EA group.Compared to those in the model group,the spinal inflammatory damages were less in the EA group at each time point,which had an improving trend.In terms of the expressions of IL-1β,IL-18 and NLRP3 in spinal cord tissues detected by IHC,they were significantly increased in the model group compared to those in the sham operation group(P<0.05);compared to those in the model group,they were significantly decreased in the EA group compared to those in the model group at 3 d,7 d and 21 d(P<0.05).In terms of the protein expression of NLRP3 detected by Western blot,it was lower in the sham operation group;it was significantly increased in the model group and the EA group at 1 d,3 d,7 d and 21 d(P<0.05);it was significantly decreased in the EA group compared to that in the model group at 3 d,7 d and 21 d(P<0.05).Conclusion:Jiaji EA can reduce inflammation reactions after SCI,which mechanism maybe related to down-regulating the expressions of NLRP3,IL-18 and IL-1βin SCI rats.