Effect Of Stress On Bile Acid Metabolize Pathway Of Broiler Chickens

In order to explore the specific effects of stress on bile acid pathway in poultry, in accordance to the lipid metabolism and the AMPK pathway, this paper investigates the following research.This study aimed at underlying the impact of glucocorticoid treatment on the bile acid metabolic pathway and genes related to the lipid metabolism on isolated liver cells. The cultured primary hepatocytes were respectively treated with 200nmol/L, 500nmol/L and1000nmol/L glucocorticoid sodium phosphate along with Williams ’E medium. The results showed that the LXR, NTCP, FATP-1, SREBP-1C and APOB100 mRNA expression levels in the hepatocytes treated with glucocorticoids were significantly decreased(P<0.05) while the gene expression of BSEP was significantly increased(P<0.05). Moreover, glucocorticoid treatment impaired the lipid metabolism and raised bile acid secretion in the hepatic cells.In this experiment, we studied the effects of distinct stressors on the bile acid and lipid metabolisms through heat stress, glucocorticoid and energy level treatments. For the heat stress trial, a total of 48 28-day-old broilers with similar body weights were selected and randomly allocated to four groups: heat stress for 72 hours(31±1℃), control treatment for 72hours(25±1℃), heat stress for 24 hours(31±1℃) control treatment for 24 hours(25±1℃).The glucocorticoid experiment consisted in selecting a total of 48 28-day-old broilers with similar body weights that were randomly assigned them to four groups: glucocorticoid treatment for 72 hours(DEX 2.0mg/kg), control treatment for 72 hours(saline, 2.0mg/kg),glucocorticoid treatment for 24 hours(DEX 2.0mg/kg) and control group for 24 hours(saline,2mg/kg). The experiment with different energy levels was conducted as follows: 2181-day-old male AA broilers with similar body weights and randomly divided into three groups:the low energy group, the high energy group and the control group. Every group had six replicates of 12 chickens each. The dietary energy level of low energy group, the high energy level group and the control group were 2900kcal/kg, 3500kcal/kg and 3200kcal/kg respectively. The results showed that heat stress significantly increased FATP-1, SREBP-1Cand APOB100 mRNA expression levels(P<0.05) while glucocorticoids significantly reduced the FXR, LXR, CYP7A1, FATP-1, SREBP-1C and APOB100 gene expression levels(P<0.05). High energy diets significantly increased the mRNA expression of SREBP-1C(P<0.05). In this way, heat stress and high energy diets may be recognized to promote the lipid metabolism whereas glucocorticoids may reduce the lipid metabolism and the bile acid synthesis.This study has explored the effects of dietary bile acid supplementation in vitro on the bile acid metabolism and the lipid metabolism. This trial was conducted on 200 1-day-old male AA broilers with similar body weights. The birds were randomly allocated to five groups:four groups of bile acids-supplemented diet at distinct dosages(100g/t, 200g/t, 300g/t, 400g/t)and a control group. Every group had 4 replicates of 10 chickens each. The results showed that adding bile acids at a dose of 400g/t significantly reduced poultry performance and blood LDL levels(P<0.05). SREBP-1C and FXR mRNA expression levels were significantly reduced(P<0.05) whereas NTCP and BSEP gene level were increased significantly(P<0.05)in the liver. In this way, the dietary supplementation may reduce bile acid synthesis in vivo,improving the enterohepatic circulation of bile acids.This study explored the impact of different dietary energy levels on the bile acid metabolism pathway of stressed broilers. This trial was conducted on 432 1-day-old male AA broilers with similar body weights. The birds randomly divided into six groups: the control group with low energy stress, the control group with high energy stress, the control group with standard energy stress, the stress group of low energy, the stress group of high energy and the stress group of standard energy. Every group had 6 replicates of 12 chickens each. The results of the study showed that the change in dietary energy levels may strengthen the effect of stress on the lipid metabolism in broilers.The study showed that heat stress and diet with high energy increased lipid metabolism in poultry liver samples. Glucocorticoids reduced the bile acid synthesis in the liver and impeded the lipid metabolism. Bide acid dietary supplementation may improve poultry performance, reduce the bile acid synthesis and promote the bile acid secretion. Under stress exposure, glucocorticoids may reduce the lipid metabolism. Changing the energy level of the diet increased the impact of stress on poultry.