高剂量铜摄入对小鼠肝肾组织形态及抗氧化功能的影响

EFFECTS OF HIGH COPPER DOSE ON MORPHOLOGY AND ANTIOXIDANT FUNCTION OF LIVER AND KIDNEY IN MICE

目的研究摄入高剂量铜对小鼠肝肾组织结构和抗氧化功能的影响。方法将50只30日龄健康昆明小鼠随机分为5组(n=10),即对照组、实验Ⅰ组、实验Ⅱ组、实验Ⅲ组和实验Ⅳ组,分别按硫酸铜0、20、50、100、100 mg/kg bw灌胃,其中实验Ⅳ组饮用500 mg/L维生素C(VC)溶液,其余各组自由饮用蒸馏水。实验持续28d。肝肾取材后制作石蜡切片,观察组织结构,并进行肝肾组织抗氧化功能测定。结果与对照组相比,铜摄入过多时,肝实质疏松,细胞间隙增大;肾间质增宽,肾小球完整性受损,排列紊乱。低剂量铜(20mg/kg)摄入时,肝肾组织中总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)、谷胱甘肽氧化化物酶(GSH-Px)活性升高、MDA含量降低;高剂量铜(≥50mg/kg)摄入时,T-AOC、SOD、GSH-Px活性降低、丙二醛(MDA)含量增多。补充VC组与同浓度铜摄入组(实验Ⅲ组)比,肝组织T-AOC、SOD、GSH-Px活性升高,MDA含量降低;肾组织T-AOC、SOD、和GSH-Px活性无显著变化,MDA含量降低。结论铜摄入过多会影响小鼠肝脏、肾脏正常形态与功能,扰乱其氧化还原平衡,VC能够提高组织的抗氧化能力。

Objective To study the effects of high dose of copper on morphology and antioxidant function of liver and kidney in mice. Methods Fifty healthy 30 d kunming mice were randomly divided into five groups（n=10）： control group. the experimental group Ⅰ, Ⅱ,Ⅲ and Ⅳ. Each group was gavaged with copper sulfate at doses of 0, 20, 50, 100, 100 mg/kg bw, respectively. All mice drank distilled water except group Ⅳ 500 mg/L VC solution was provided. The experiment lasted for 28d and then the mice were killed. Liver and kidney tissue paraffin sections were observed and antioxidant function was determined. Results Compared to the control group, diminished hepatic parenchymal cells and increased cellular gap were observed in copper treatment groups, widening kidney interstitial, damaged glomerular integrity were also observed. The T-AOC, SOD, and GSH-Px activities of liver and kidney tissues increased and MDA content decreased in low dose（20mg/kg） of copper intake group. However the T-AOC activities of SOD and GSH-Px decreased and MDA content increased in higher dose of copper（≥50mg/kg） intake groups. Compared to the VC supplemented group to the same dose of copper intake（group Ⅲ）, T-AOC, SOD, GSH-Px activities in liver increased and MDA content decreased. However, the activities of renal antioxdative enzymes did not change significantly and MDA content decreased. Conclusion The redox balance of liver and kidney was disrupted and resulted in significant morphologic changes in liver and kidney after intake of excessive copper. VC supplementation increases antioxidant capacity of liver and kidney and protects them against copper-induced oxidative stress.