白藜芦醇对热应激肉鸡肝脏抗氧化功能和Nrf2通路相关基因表达的影响

Effects of resveratrol on antioxidant function and the expression of Nrf2 signaling pathway-related genes in liver of heat-stressed broilers

[目的]本试验旨在研究白藜芦醇对热应激肉鸡肝脏抗氧化功能和核因子E2相关因子2(Nrf2)通路相关基因表达的影响。[方法]300羽1日龄爱拔益加(AA)公鸡饲养至21日龄时选取其中54羽体重相近的肉鸡,随机分为3组,每组3个重复,每个重复6羽。对照组[(22±1)℃,24 h)]和热应激组[(33±1)℃,10 h;(22±1)℃,14 h)]饲喂基础饲粮,热应激+白藜芦醇组饲喂在基础饲粮中添加400 mg·kg^(-1)白藜芦醇的试验饲粮。试验期21 d。[结果]与对照组相比,热应激组肉鸡终末体重、平均日增重(ADG)、平均日采食量(ADFI)、肝脏指数、脾脏指数、胸腺指数、血清中葡萄糖(GLU)含量和总蛋白(TP)含量,肝脏中核因子E2相关因子(Nrf2)、亚铁血红素加氧酶(HO-1)、超氧化物歧化酶1(SOD1)mRNA表达量及过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GPX)、谷胱甘肽疏基转移酶(GSH-ST)、SOD活性均显著降低(P<0.05);而料重比(F/G)、血清中谷丙转氨酶(ALT)活性、甘油三酯(TG)和总胆固醇(TC)含量、肝脏中Kelch样环氧氯丙烷相关蛋白1(Keap1)mRNA表达量及丙二醛(MDA)和蛋白质羰基(PC)含量均显著升高(P<0.05)。与热应激组相比,热应激+白藜芦醇组肉鸡F/G、血清中ALT活性、肝脏中Keap1 mRNA表达量及MDA含量显著降低(P<0.05);而终末体重,ADG,脾脏指数,胸腺指数,血清中GLU、TP含量,肝脏中Nrf2、HO-1、SOD1 mRNA表达量和GPX、SOD活性显著升高(P<0.05)。[结论]白藜芦醇对热应激肉鸡生长性能、免疫器官发育、血清生化指标及抗氧化功能具有促进作用,其改善抗氧化功能的机制可能与其激活Nrf2信号通路有关。

[Objectives]The study was to investigate the effect of resveratrol on antioxidant function and the expression of nuclear factor erythroid 2-related factor 2(Nrf2)signaling pathway-related genes in liver of heat-stressed broilers.[Methods]Three hundred 1-day-old male AA broilers were reared up to 21 days of age,and then fifty-four broilers with similar body weight were selected and randomly assigned to 3 groups with 3 replicates of 6 birds each.Birds in the control group[(22±1)℃,24 h)]and the heat-stress group[(33±1)℃,10 h;(22±1)℃,14 h)]were fed the basal diet,and birds in the heat-stress+resveratrol group were fed the basal diet supplemented with 400 mg·kg^(-1) resveratrol.The treatment lasted for 21 days.[Results]Compared with the birds in the control group,the birds in the heat-stress group exhibited lower(P<0.05)final body weight,average daily gain(ADG),average daily feed intake(ADFI),liver index,spleen index,thymus index,serum glucose(GLU)and total protein(TP)contents,hepatic Nrf2,heme oxygenase(HO-1),superoxide dismutase 1(SOD1)mRNA expression levels and catalase(CAT),glutathione peroxidase(GPX),glutathione S-transferase(GSH-ST),and SOD activities;but they exhibited higher(P<0.05)ratio of feed to gain(F/G),serum alanine aminotransferase(ALT)activity,triglyceride(TG)and total cholesterol(TC)contents,hepatic Kelch-like epichlorohydrin-related protein 1(Keap1)mRNA expression and malondialdehyde(MDA)and protein carbonyl(PC)contents.Compared with the birds in the heat stress group,the birds in the heat-stress+resveratrol group exhibited lower(P<0.05)F/G,serum ALT activity,hepatic Keap1 mRNA expression level and MDA content;but they exhibited higher(P<0.05)final body weight,ADG,spleen index,thymus index,serum GLU and TP contents,hepatic Nrf2,HO-1,SOD1 mRNA expression levels and GPX and SOD activities.[Conclusions]Resveratrol can promote growth performance,immune organ development,serum biochemical parameters and antioxidant capacity of heat-stressed broilers,and the underlying mechanism for improving antioxidant capacity may be attributed to the activation of the Nrf2 signaling pathway.