Exogenous adiponectin attenuates lipid accumulation and is associated with enhanced TG and VLDL secretion in primary...

Adiponectin (ADPN) is an adipocyte-derived peptide that exerts a pivotal regulatory role in lipid metabolism in mammals. However, its functional role in avian lipid metabolism needs to be further explored, particularly in the liver, the central organ governing metabolic homeostasis in poultry. In this study, the effects of exogenous recombinant adiponectin on lipid metabolism processes were examined in primary chicken hepatocytes. Regardless of palmitic acid pretreatment, adiponectin significantly attenuated intracellular lipid accumulation. Mechanistically, adiponectin was accompanied by increased adiponectin receptor 2 (ADPNR2) mRNA expression and stimulated the efflux of triglycerides (TG) and very low-density lipoproteins (VLDL) from hepatocytes. These effects were accompanied by short-term activation of the AMP-activated protein kinase (AMPK) signaling pathway. Meanwhile, adiponectin enhanced the cellular uptake of glucose and fatty acids and upregulated the expression of genes related to fatty acid synthesis. It also suppressed the expression of genes involved in fatty acid oxidation, suggesting a cell-intrinsic negative feedback mechanism. In conclusion, the results indicate that enhanced lipid efflux may be an important mechanism contributing to the adiponectin-mediated reduction of hepatic lipid accumulation. These findings provide further evidence for the involvement of adiponectin in the regulation of avian hepatic lipid metabolism and suggest that adiponectin and its receptor pathways may represent potential targets for future studies aimed at improving liver health and productivity in poultry.