Liver X receptor α participates in LPS-induced reduction of triglyceride synthesis in bovine mammary epithelial cells

Abstract

Lipopolysaccharides (LPS) could induce milk fat depression via regulating the body and blood fat metabolism. However, it is not completely clear how LPS might regulate triglyceride synthesis in dairy cow mammary epithelial cells (DCMECs). DCMECs were isolated and purified from dairy cow mammary tissue and treated with LPS. The level of triglyceride synthesis, the expression and activity of the liver X receptor α (LXRα), enzymes related to de novo fatty acid synthesis, and the expression of the fatty acid transporters were investigated. We found that LPS decreased the level of triglyceride synthesis via a down-regulation of the transcription, translation, and nuclear translocation level of the LXRα. The results also indicated that the transcription level of the LXRα target genes, sterol regulatory element binding protein 1 (SREBP1), fatty acid synthetase (FAS), acetyl-CoA carboxylase-1 (ACC1), were significantly down-regulated in DCMECs after LPS treatment. Our data may provide new insight into the mechanisms of milk fat depression caused by LPS.

N-Acetylcysteine alleviates high fat diet-induced hepatic steatosis and liver injury via regulating the intestinal microecology in mice

“…2A †). Some studies found that LPS intervention inhibited TG synthesis and secretion in bovine mammary epithelial cells (DCMECs), 46,47 while other studies found that 4-week LPS (300 μg kg −1 d −1 ) infusion increased liver TG contents in C57BL/6J mice, 48 and intraperitoneal injection of LPS in mice accelerated hepatic fat accumulation. 49 This scientific question needs to be further explored.…”