决明子提取物对链脲佐菌素诱发糖尿病小鼠 晶状体氧化应激状态的影响

目的:研究决明子提取物Cassia obtusifolia extract(COE)对链脲佐菌素(STZ)诱发糖尿病小鼠晶状体氧化应激状态的改善作用。方法:雄性昆明种小鼠尾静脉注射STZ 130 mg·kg-1造成糖尿病模型后,分成STZ模型组、二甲双胍组(300 mg·kg-1,ig)、决明子提取物低、中、高给药组(50,150,450 mg·kg-1,ig),每组10只,每天ig 1次,连续给药10 d后。检测小鼠血糖浓度和晶状体氧化应激状态相关指标抗氧化能力指数(ORAC)、丙二醛(MDA)、一氧化氮(NO)、谷胱甘肽(GSH)、超氧化物歧化酶(T-SOD)和谷胱甘肽过氧化物酶(GSH-Px)的改善作用。结果:小鼠尾静脉注射STZ 7 d后,诱发小鼠血糖值明显增高(P<0.01),同时造成晶状体的氧化损伤。同时与模型组相比,决明子提取物没有显示有效的降血糖作用(P>0.01),但决明子给药均能显著降低小鼠晶状体的氧化应激产物NO和MDA含量(P<0.01),同时提高晶状体的抗氧化能力指数ORAC和GSH水平(P<0.01),并提高小鼠晶状体组织内抗氧化的自由基清除系统相关酶(T-SOD和GSH-Px)的活性(P<0.01)。结论:决明子提取物可以改善STZ诱导糖尿病小鼠晶状体内的过氧化状态,其作用机制可能通过清除自由基和抑制脂质过氧化过程实现的。

Effects of Cassia obtusifolia Extract on Oxidative Stress Status in STZ-induced Diabetic Mice

Objective : To study the protective effects of Cassia obtusifolia extract (COE) on oxidative stress of lens in streptozotocin (STZ)-induced diabetic mice. Method: STZ (130 mg·kg^-1) was intravenously injected from the tail vein to induce diabetes in mice, which were randomly divided into STZ model, metformin positive control (300 mg·kg^-1), and different dosages of COE (50, 150,450 mg·kg^-1), with 10 mice in each group. Metformin and COE were given to mice once daily for 10 consecutive days by oral administration, while normal control and STZ model groups were given water only. Blood glucose level and parameters of oxidative stress oxygen radical absorbance capacity(ORAC), malonaldehyde(MDA), nitric oxide(NO), L-glutathione(GSH), total superoxide dismutase(T-SOD) and glutathione eroxidase (GSH-Px) were detected in mice lens. Result: STZ injection increased plasma glucose significantly and also induced oxidative stress in mice lens. Although COE was not effective on the elevated blood glucose level, it could significantly lower the contents of NO and MDA in lens (P<0. 01). At the same time, ORAC and GSH levels of lens were significantly increased (P<0. 01). The activity of T-SOD and GSH-Px was also increased (P<0. 01). Conclusion: COE could improve oxidative stress conditions in lens of STZ-induced diabetic mice. The mechanism should be related to the elimination of free radicals and inhibition of lipid peroxidation.