α-硫辛酸对糖尿病大鼠坐骨神经氧化应激和细胞凋亡的影响

Effects of alpha lipoic acid on oxidative stress and apoptosis of sciatic nerve in diabetic rat

目的:探讨糖尿病大鼠坐骨神经氧化应激和细胞凋亡及α-硫辛酸的干预作用。方法:腹腔注射链脲佐菌素(STZ)诱导成糖尿病大鼠模型,随机分为糖尿病组、α-硫辛酸干预组,后者给予α-硫辛酸20 mg/(kg.d),并以正常组作对照。8周后分离所有大鼠坐骨神经,检测神经组织中过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)的活性及丙二醛(MDA)的含量;用原位末端标记法(TUNEL法)检测坐骨神经细胞凋亡。结果:与正常对照组相比,糖尿病组坐骨神经组织中CAT、SOD、GSH-Px水平明显下降(P<0.01),MDA水平显著升高(P<0.01);与糖尿病组相比,干预组CAT、SOD、GSH-Px水平升高(P<0.05),MDA水平下降(P<0.05)。糖尿病组坐骨神经节细胞凋亡指数(AI)较对照组升高(P<0.05),干预组AI较糖尿病组下降(P<0.05)。结论:高血糖可引起大鼠坐骨神经氧化应激和细胞凋亡,α-硫辛酸能抑制神经组织中的氧化应激、减少神经细胞凋亡,为临床治疗糖尿病神经病变提供新的方向。

Objective： Objective： To explore the oxidative stress damage on the sciatic nerve of diabetic rats,and the beneficial effect of antioxidant alpha lipoic acid.Methods： Diabetic rat model was induced by intraperitoneal injection of streptozotocin（STZ）,and the diabetic rats were randomly divided into two groups： diabetic control group（DM）,treated group（LA）,administrated by alpha-lipoic acid 20mg/（kg.d）.And the normal rats were served as a normal control group（NC group）.The sciatic nerves of all the rats were separated after eight weeks later,the removed nerves were used for detecting the activities of catalase（CAT）、superoxide dismutase（SOD）、glutathione peroxidase（GSH-Px） and the levels of malondialdehyde（MDA）;apoptosis cells in sciatic nerves were identified by terminal-deoxynucleotidyl transferase mediated d-UTP nick end labeling（TUNEL）.Results： Compared with the NC group,the activities of CAT,SOD and GSH-Px were significantly reduced and the levels of MDA were significantly increased in the DM group（all P0.01）;compared with the DM group,the activities of CAT,SOD and GSH-Px were increased and the levels of MDA were reduced in the treated groups（all P0.05）.Compared with the NC group,the apoptotic index（AI） of sciatic nerve cells were increased in the DM group（P0.05）;compared with the DM group,the apoptotic index（AI） of sciatic nerve cells were reduced in treated group（P0.05）.Conclusion： Hyperglycemia can cause oxidative stress and induce apoptosis in sciatic nerve of diabetic rats.Alpha-lipoic acid can reduce the apoptosis of nerve cell induced by attenuate oxidative damage,which afford a new path for treating the diabetic neuropathy.