Overexpression of irisin reduces embryonic and diet-induced hepatic lipid accumulation in chickens

Excessive lipid accumulation in the liver can lead to fatty liver disease, which causes substantial economic losses in the poultry industry. To investigate whether irisin could alleviate hepatic lipid accumulation in 19-day-old chicken embryos or in high-fat diet (HFD)-induced models, we constructed transgenic chimeric chickens overexpressing irisin by embryonic injection of lentiviral or adenoviral vectors. The results showed that these chickens exhibited stable and sustained high-level expression of irisin in vivo, which significantly improved lipid content and liver injury markers in both serum and liver, as determined by biochemical assays and histological analysis. Gene expression analysis of liver tissue samples revealed that irisin overexpression inhibited lipogenesis and promoted lipolysis. Moreover, overexpression of irisin reduced levels of oxidative stress markers and suppressed the expression of pro-inflammatory factors. These findings provide a foundation for the use of irisin as an interventional treatment for fatty liver disease in chickens.