“夹脊”电针对兔退变腰椎间盘组织中基质金属蛋白酶13和基质金属蛋白酶组织抑制因子1表达的影响

Effects of Electroacupuncture Stimulation of “Jiaji”(EX-B 2) on Expression of Matrix Metalloproteinase-13 and Tissue Inhibitor of Metalloproteinase-1 in Intervertebral Disc Tissue in Rabbits with Lumbar Intervertebral Disc Degeneration

目的:研究"夹脊"电针对兔退变的腰椎间盘中基质金属蛋白酶13(matrix metalloproteinase-13,MMP-13)和基质金属蛋白酶组织抑制因子1(tissue inhibitor of metalloproteinase-1,TIMP-1)表达的影响,探讨夹脊电针治疗腰椎间盘退行性病变的作用机制。方法:36只清洁级成年新西兰大白兔随机分为正常组、假手术组、模型组和电针组,每组9只。采用克氏针横穿椎体后椎体间加压法复制椎间盘退变模型。电针组针刺L 4、L 5"夹脊"穴28d。各组于第1、28、56天应用Western blot方法检测椎间盘组织中MMP-13蛋白的表达,免疫荧光技术检测椎间盘组织中TIMP-1蛋白的表达。结果:建立模型后,MMP-13蛋白表达增强(P<0.01);电针进行干预后可降低MMP-13的表达(P<0.01)。TIMP-1在荧光激发下,胞质清晰,可见红色荧光,其中各组第1天和正常组、假手术组的第28、56天均呈现强阳性,模型组第56天阳性细胞最少、红色荧光最弱(P<0.01),而电针组在第56天阳性细胞升高(P<0.01)。结论:电针"夹脊"穴可以通过降低椎间盘组织中MMP-13和增强TIMP-1的表达,纠正基质合成与分解代谢失衡,达到防治椎间盘退变的效果。

Objective To observe the effect of electroacupuncture（EA） stimulation of ＂Jiaji＂ （EX-B 2） on the expression of matrix metalloproteinase-13 （MMP-13） and tissue inhibitor of metalloproteinase-1 （TIMP-1） proteins in the lumbar disc in rabbits with lumbar intervertebral disc degeneration so as to explore its mechanism in relieving intervertebral disc degeneration. Methods A total of 36 New Zealand rabbits were randomly divided into normal, sham operation （sham）, model, and EA groups, with 9 rabbits in each group. The lumbar intervertebral disc degeneration model was established by using a custom-made external loading device to axially compress the lumbar discs （L 4, L 5） for 28 days in reference to Kroeber and colleagues＇ methods. After modeling, EA stimulation （2 Hz/15 Hz, 1 -2 mA） was applied to bilateral ＂Jiaji＂ （EX-B 2） areas for 20 min, once daily for 28 days. The expression levels of MMP-13 and TIMP-1 proteins of the lumbar intervertebral disc （L 4-L 5） tissues were assayed by Western blot and immunoflorescence methods, separately. Results Compared to the normal and sham groups, MMP-13 expression levels at the time-points of day 28 in the model group, on day 28 （pre-EA） in the EA group were significantly up-regulated （P〈0.01）; and T[MP-1 expression levels on day 28 in both model and EA groups were significantly decreased （P〈0.01）. Following EA treatment, the expression level of MMP-13 was notably lower in the EA group than in the model group, and that of TIMP-1 was remarkably higher in the EA group than in the model group （ P〈0. 01 ）. No significant differences were found in the expression levels of MMP-13 and TIMP-1 from day 1 to day 56 in the same one group of both normal and sham groups, and between these two groups （P〉0.05）. Conclusion Electroacupuncture at ＂Jiaji＂ （EX-B 2） can effectively suppress inter- vertebral disc degeneration induced up-regulation of MMP-13 protein and down-regulation of TIMP-1 protein in the disc tissue in rabbits, which may contribute to its effect in bettering lumbago in clinic.