硒和蛋白质对大鼠心肌蛋白质及DNA修复酶的影响

The effects of selenium and protein on myocardial protein and DNA repair enzymes of rats

目的研究低硒低蛋白引起的氧化应激对大鼠心肌蛋白质及DNA修复酶的影响。方法 60只健康雄性Wistar大鼠,按体重随机分为4组,每组15只:低硒低蛋白组(A)、常硒低蛋白组(B)、低硒常蛋白组(C)和常硒常蛋白组(D),饲养1年。处死后,采用2,4-二硝基苯肼(DNPH)比色法检测大鼠心肌蛋白质羰基的含量;提取心肌组织总RNA,采用实时荧光定量PCR方法检测DNA修复酶(OGG1和MUTYH)mRNA表达水平;Western blot方法检测DNA修复酶(OGG1和MUTYH)的蛋白表达水平。结果各组之间蛋白质羰基含量的差别没有统计学意义;OGG1和MUTYH的mRNA表达水平,其中均为常硒组的总体均数高于低硒组,常蛋白组的总体均数高于低蛋白组,差异具有统计学意义(P<0.05);MUTYH的蛋白表达,常硒组的总体均数高于低硒组,常蛋白组的总体均数高于低蛋白组,差异具有统计学意义(P<0.05)。结论长期低硒低蛋白饮食可能会影响机体DNA修复酶(OGG1和MUTYH的活力,但是蛋白质羰基的含量没有变化。

Objective To investigate the oxidative damage effect of selenium and protein on myocardial protein and DNA repair enzymes in rat myocardium. Methods 6o healthy male Wistar rats were randomly divided into four groups according to their body weight, each group with 15 rats. Group A was low-protein and low- selenium group, group B normal-Se and low-protein group, group C low-selenium and normal-protein group, group D normal-Se and normal-protein group. After being fed for 12 months,all rats were killed and the protein carbonyl in cardiocytes was measured. Total RNA was extracted from heart, and the OGG1 and MUTYH mRNA expressions were detected by real-time PCR. Proteins were extracted from heart and their expressions were detected with Western blot. Results The mRNA expression of OGG1 and MUTYH was higher in the adequate selenium groups than in the selenium deficient groups. The protein expression MUTYH was higher in the adequate selenium groups than in the deficient groups. Conclusion The DNA repair enzymes （OGG1 and MUTYH） may be closely related to selenium.