女贞子提取物对糖尿病肾病大鼠糖脂代谢及氧化应激的影响

目的:观察女贞子提取物对糖尿病肾病(diabetic nephropathy,DN)大鼠血糖、血脂及肾皮质氧化应激的影响,探讨女贞子提取物对糖尿病肾病大鼠肾脏的保护作用机制。方法:将65只大鼠随机分为正常对照组,DN模型组,女贞子提取物低剂量组、中剂量组、高剂量组,缬沙坦阳性对照组。模型组、女贞子提取物各组和缬沙坦组采用一次性腹腔注射法注射55 mg·kg~(-1)链脲佐菌素构建糖尿病肾病大鼠模型,造模成功后分别灌胃生理盐水1 m L·(kg·d)~(-1)、女贞子提取物0.2g·(kg·d)~(-1)、0.4 g·(kg·d)~(-1)、0.8 g·(kg·d)~(-1)、缬沙坦10 mg·(kg·d)~(-1);正常组灌胃生理盐水1 m L·(kg·d)~(-1),各组均每日给药1次。实验第8周末处死大鼠,检测大鼠体质量、空腹血糖(fasting blood-glucose,FBG)、血脂及肾皮质中丙二醛(malonaldehyde,MDA)水平和超氧化物歧化酶(superoxide dismutase,SOD)活性。结果:与正常组比较,模型组大鼠FBG、血脂、肾皮质MDA水平和SOD活性均有显著性差异(P0.01),显示造模成功。与模型组比较,女贞子提取物中剂量组、高剂量组大鼠血糖水平显著降低(P0.01);女贞子提取物中剂量组、高剂量组大鼠三酰甘油(triacylglycerol,TG)、总胆固醇(total cholesterol,TC)、低密度脂蛋白(ow density lipoprotein,LDL)、高密度脂蛋白(high-density lipoprotein,HDL)水平与模型组比较,差异均有统计学意义(P0.01或P0.05);与模型组比较,女贞子提取物中剂量、高剂量能显著降低DN大鼠肾皮质MDA水平(P0.01),提高SOD活性(P0.01);与缬沙坦组比较,女贞子提取物中剂量组、高剂量组大鼠FBG、TC、TG、LDL、HDL水平有显著性差异(P0.05),但肾皮质MDA水平和SOD活性无显著性差异(P0.05)。结论:女贞子提取物能够有效纠正DN大鼠糖、脂代谢紊乱,对DN有良好的防治作用,其机制可能与降低血糖、降低血脂及减轻肾皮质氧化应激水平有关。

Study on the Effect of Glossy Privet Fruit Extract on Blood Glucose and Lipid Metabolism and Oxidative Stress in Diabetic Nephropathy Rats

Objective:To observe the effects of glossy privet fruit extract on the blood glucose,blood lipid and renal cortical oxidative stress of rats with diabetic nephropathy (DN),and to discuss the protective mechanisms of glossy privet fruit extract for the kidneys of rats with diabetes.Methods:65 rats were randomly divided into the normal control group,DN model group,low-dose glossy privet fruit extract group,middle-dose glossy privet fruit extract group,high-dose glossy privet fruit extract group and positive valsartan control group.Rats of the model group,extract groups and valsartan group were respectively injected with streptozotocin (STZ) of 55 mg · kg-1 by one-time abdominal injection to construct the DN rat models.After modeling,the rats were respectively dosed with normal saline of 1 mL · (kg · d)-1,glossy privet fruit extract of 0.2 g · (kg · d)-1,0.4 g · (kg · d)-1,0.8 g · (kg · d)-1 and valsartan of 10 mg · (kg · d)-1 by gavage;rats of the normal group were given normal saline of 1 mL · (kg · d)-1 by gavage,and each group was dosed once daily.At the end of the eighth week of the test,the rats were executed,and their body masses,fasting blood-glucose (FBG),blood lipid,renal cortex malonaldehyde (MDA) content and superoxide dismutase (SOD) activity were examined.Results:Compared with rats of the normal group,those of the model group were distinctively different in aspects of FBG,blood lipid,renal cortex MDA content and SOD activity (P ＜ 0.01),indicating that the modeling was successful.Compared with rats of the model group,those of the middle-dose and high-dose groups showed a remarkable decrease in blood glucose (P ＜ 0.01);the differences between the rats of the middle-dose and high-dose groups and the model group in triacylglycerol (TG),total cholesterol (TC),low density lipoprotein (LDL) and high-density lipoprotein (HDL) were of statistical significance (P ＜0.01 or P ＜0.05);compared with rats of the model group,the DN rats in the middle-dose and high-dose groups showed remarkably reduced MDA contents (P ＜ 0.01) and increased SOD activities (P ＜ 0.01);compared with the rats of the valsartan group,those of the middle-dose and high-dose groups were distinctively different in FBG,TC,TG,LDL and HDL (P ＜ 0.05),while their renal cortex MDA content and SOD activity showed no obvious difference (P ＞ 0.05).Conclusion:The glossy privet fruit extract can effectively recover the metabolic disorders of the blood glucose and blood lipid of the DN rats,and has excellent prevention and curing effects for DN.The mechanism might be related with the reduction of blood glucose,blood lipid and renal cortical oxidative stress.