Effect Of Adiponectin On Skeletal Muscle Lipid Metabolism In Broilers

The experiments were conducted to study the role of adiponectin on skeletal muscle intramuscular lipid ectopic accumulation in broilers. In this study, we from the direction of “fatty acid oxidation influce the fatty deposition” to study the role of adiponectin. we investigate the effect of adipinectin on lipid accumulation through using the experimental models of both in vivo and in vitro. The methods of cell culture, Real-time PCR and Western blotting are used in the present study. According to our experimental protocol, the models of lipid ectopic accumulation are induced in vivo by different growth period, or by high/lean chickens, or by DEX treatment, and are induced in vitro by DEX. We examine the protein expression of adiponectin and fatty acid oxidation to explore whether adiponectin is involved in fatty acid oxidation or accumulation. This study will be processed across the transcription, translation and cellular levels. The findings will further extend our understanding of adiponectin role on body energy redistribution, and will provide a theoretical basis for guilding poultry farming and improving meat quality.The expression of adiponectin in time and space of broilers. We choose 120 1-day-old Arbor Acres(AA). Feed and water were provided ad libitum for 7 weeks. We collect the sample every week. From the results we found that the plasma adiponectin level is increased by the days, but the mRNA expression of adiponectin and adiponectin receptor(adipoR1, adipo R2) in muscle and abdominal fat is decreased by days. This shows that with the increase of weeks, the ability of fat deposition is strengthen, and the secretion of adiponectin in adipose tissue and the function of adiponectin decreased. Those suggest that adiponectin has may participate in the regulation of skeletal muscle fatty deposits.The relationship between adiponectin and fat deposition ability of broilers. We choose 60 42-day-old AA divide into two groups: fat and normal groups. In fat、control groups, we found that the mRNA expression of adiponectin and adiponectin receptor in muscle and abdominal fat in fat group is lower than normal. The abdominal fat rate in fat group is higher than control group. But the concentration of adiponectin in plasma in fat group is lower than control group. This suggest that the fat oxidation ability in skeletal muscle of adiponectin is in decreased,which leads to the increase of the content of body fat.The relationship between adiponectin and fat deposition ability of different poultry. We choose 10 42-day-old AA and 10 42-day-old hens. From the results we found that the abdominal fat rate in broiler is highers than in hens, but the mRNA expression of adiponectin and adiponectin receptor in abdominal fat is lower. As the trial 2, the concentration of adiponectin in plasma in broilers is lower than hens. This suggest that the fat oxidation ability in skeletal muscle of adiponectin is in decreased, which leads to the increase of the content of body fat.The relationship between DEX and fat metabolism under different energy states of broilers. We choosed 60 35-day-old AA broilers randomly divided into two groups for two weeks of high energy/low energy feeds(HE/LE) treatments, and in thirty-five day, HE/LE groups divided into two groups: one is injected saline for one week and another group is injected dexamethasone(DEX) for one week. From the results we found that DEX can significantly decrease the mRNA expression of adiponectin in abdominal fat. DEX can significantly decrease the concentration of adiponectin in plasma. DEX significantly decrease the p-ampk level in breast and leg. These results indicate that adiponectin may be though the AMPK-CPT1 to adjust the intramuscular lipid ectopic accumulation in broilers.The role of adiponectin on the fat metabolism in chicken myoblast. Myoblast was prepared from SPF chicken embryos(15-d old), then subjected to following treatments:1uM DEX and control for 24 hours. From the results we can know that DEX can increase the fat deposition in myoblast, and can decrease the activation of CPT1 and change the mRNA expression of AMPK. In another trial, the cell was subjected with the treatment of 200ug/ml adiponectin and control. From the result, adiponectin can decrease the fat deposition in myoblast and increase the activation of p-AMPK and the actination of CPT1. From all the results we can know that the effect of adiponectin on fat mechanism in stress via AMPK-CPT1 pathway.