葛根素对糖尿病大鼠坐骨神经损伤的影响

Effect of puerarin on sciatic nerve injury caused by diabetes mellitus

目的:探讨葛根素对糖尿病大鼠坐骨神经的保护作用及其机制。方法:雄性SD大鼠随机分成6组:正常对照组,糖尿病模型组,葛根素高(160mg·kg-1)、中(120mg·kg-1)、低(80mg·kg-1)剂量治疗组,氨基胍(100mg·kg-1)治疗组;各组大鼠每天腹腔注射相应药物1次,正常对照组及糖尿病模型组腹腔注射等体积丙二醇。治疗12周后,测定6组大鼠血清、坐骨神经一氧化氮(NO)含量、一氧化氮合酶(NOS)活性和血浆内皮素-1(ET-1)、降钙素基因相关肽(CGRP)含量及坐骨神经丙二醛(MDA)含量、超氧化物歧化酶(SOD)、Ca2+-ATPase、Na+-K+-ATPase活性和神经元型NOS(nNOS)、醛糖还原酶(AR) mRNA的表达水平。结果:糖尿病组大鼠血液NO、CGRP含量及坐骨神经NOS、SOD、Ca2+-ATPase、Na+-K+-ATPase活性、NO含量和nNOS mRNA的表达均明显低于正常对照组(P<0.01或P<0.05),而血液NOS活性、ET-1含量和坐骨神经MDA含量、AR mRNA的表达均明显高于正常对照组(P<0.01或P<0.05);经葛根素治疗后,上述改变逆转,与糖尿病模型组比较差异有显著性(P<0.01或P<0.05)。结论:葛根素对糖尿病大鼠坐骨神经具有一定的保护作用,其机制可能与改善神经内膜血供及减轻氧化应激损伤有关。

Objective：To probe the effects and mechanisms of puerarin on sciatic nerve injury resulted from diabetes mellitus in experimental diabetic rats.Methods：The male Sprague-Dawley rats were randomly divided into normal control group,diabetic group,high dose puerarin（160 mg·kg^-1,middle dose puerarin（120 mg·kg^-1,low dose puerarin（80 mg·kg^-1treatment group and aminoguanidine（100 mg·kg^-1 treatment group.Corresponding drugs were intraperitoneally injected once a day,Equal propylene glycol were given the normal control group and diabetic group.The rats were sacrificed and their blood and sciatic nerve were collected 12 weeks later.The nitric oxide（NO） content and nitric oxide synthase（NOS）activity in serum,and the content of NO,malondialdehyde（MDA） and the activities of NOS,superoxide dismutase（SOD）,Ca^2＋-ATPase,Na^＋-K^＋-ATPase in sciatic nerve were mea-sured with colorimetric analysis.The levels of endothelin-1（ET-1） and calcitonin generelated peptide（CGRP） in plasma were determined with radioimmunoassay.In addition,the mRNA expression level of neuronal NOS（nNOS） and aldose reductase（AR） of sciatic nerve were determined with reverse transcription polymerase chain reaction（RT-PCR）.Results：The NO content in serum and sciatic nerve and plasma CGRP content,and the activities of NOS,SOD,Ca^2＋-ATPase,Na^＋-K^＋-ATPase as well as mRNA expression level of nNOS in sciatic nerve of diabetic group were significantly lower than those of normal control group（P〈 0.01 or P〈 0.05 respectively）,but plasma ET-1 level and serum NOS activity,and MDA content as well as AR mRNA expression level in sciatic nerve of diabetic group were significantly higher than those of normal control group（P〈 0.01 or P〈 0.05 respectively）.However,in puerarin treatment groups,the above changes were reversed,a significant differences of those were found as compared to those in diabetic group（P〈 0.05 or P〈 0.01 respectively）.Conclusion：Puerarin exerts preventive and remedial effects on the diabetic sciatic nerve,which may be related to improving the blood supply and relieving oxidative stress damage.