Abstract
Conjugated linoleic acid (CLA) isomers have been reported to reduce body weight and promote glycolipid metabolism in animals. In a preliminary study, we revealed that trans-10, cis-12-CLA (10,12-CLA) plays an important role in modulating lipid metabolism in chickens. However, the underlying mechanism remains unclear. In this study, we constructed an isolated in vitro model with primary chicken hepatocytes to investigate the effect of 10,12-CLA on lipid metabolism. 10,12-CLA inhibited lipid accumulation by decreasing the mRNA expression of sterol regulatory element-binding protein-1c (SREBP-1c), SREBP2, 3‑hydroxy-3-methylglutaryl-CoA reductase (HMGCR), fatty acid synthase (FAS), adipose triacylglyceride lipase (ACC), and lipoprotein lipase (LPL) and increasing the mRNA expression of peroxisome proliferator-activated receptor α (PPARα), carnitine palmitoyltransferase 1 (CPT1) and adipose triacylglyceride lipase (ATGL). Furthermore, 10,12-CLA treatment activated the protein expression of extracellular signal-regulated kinase 1/2 (ERK1/2) and AMP-activated protein kinase (AMPK), whereas treatment with the ERK1/2 inhibitor U0126 reversed the inhibitory effects of 10,12-CLA on lipid accumulation by blocking the ERK1/2-AMPK pathway, leading to increased lipid accumulation and triglyceride content in primary chicken hepatocytes. These findings suggest that in chicken hepatocytes, 10,12-CLA alleviates hepatocyte lipid deposition by activating the ERK1/2-AMPK pathway, promoting fatty acid oxidation and reducing lipid synthesis, revealing the potential mechanism through which 10,12-CLA regulates hepatic lipid metabolism in chickens.