饲料中添加复合胆汁酸对皮质酮诱导的肉鸡脂肪肝综合征的缓解作用研究OACSTPCD

[Objectives]This study aimed to investigate the effect of dietary bile acids(BA)supplementation on alleviating fatty liver syndrome(FLS)induced by corticosterone(CORT)in broilers,and the mechanism involving in this process.[Methods]One hundred and twenty 1-day-old AA male broilers were randomly divided into two groups and fed a basal diet or a BA containing diet respectively.BA were periodically added to the diet using the dose-escalation strategy including early,middle and late stages.At 28 days of age,twenty broilers were randomly selected from the basal diet group and divided into control group(CON)and corticosterone treatment group(CORT).Ten broilers fed BA were randomly picked up and set as corticosterone plus bile acids group(CORT+BA).The broilers were slaughtered at 40 days of age.The weight of organs and tissues was recorded.The serum and liver tissues were sampled for biochemical analysis and hepatic genes or proteins expression analysis.[Results]BA treatment significantly alleviated the deposition of abdominal fat and the decrease of leg muscle weight induced by CORT injection,and also increased leg muscle percentage(P<0.05).The results of biochemical analysis showed that CORT treatment significantly decreased serum high-density lipoprotein(HDLC)concentration,but increased serum non-esterified fatty acid(NEFA)level,while BA significantly increased the level of serum HDLC(P<0.05).The level of hepatic triglyceride(TG)was significantly increased by CORT(P<0.01)and the lipid droplets in liver were significantly enriched and vacuolated.However,these changes were markedly alleviated by BA treatment(P<0.05).Compared to the CON group,CORT significantly up-regulated the mRNA expression of stearoyl-CoA desaturase 1(scd1)and acetyl CoA carboxylase(acc)genes,and also significantly up-regulated the protein expression of ACC and fatty acid synthase(FASN)but down-regulated peroxisome proliferator activated receptor alpha(PPARα)protein expression in the liver(P<0.05).BA supplementation ameliorated the disorders of hepatic lipid metabolism caused by CORT and increased the mRNA expression of carnitine palmitoyl-transferase 1A(cpt1a)and decreased protein expression of fatty acid translocase(CD36)(P<0.05).[Conclusions]Dietary BA supplementation can significantly alleviate hepatic TG deposition induced by CORT through decreasing hepatic TG synthesis,promoting fatty acid decomposition,as well as inhibiting hepatic fatty acids uptake in broilers.