Lipidomic profiling reveals the dynamic changes of hepatic lipidome during the fasting-refeeding transition in mice

Liver plays a pivotal role in maintaining energy homeostasis during fasting-refeeding transition. We previously reported that fasting-refeeding induces the dynamic changes of liver size. However, the alterations in hepatic lipid profiles during these dynamic changes remain unclear. Therefore, the present study aimed to clarify the effect of fasting and refeeding on hepatic lipid homeostasis in mice using lipidomics analysis and to identify the specific lipids that vary during the fasting-refeeding transition. In this study, C57BL/6 mice were fasted for 24 h and subsequently refed for 1, 3, 6, 12, and 24 h, respectively. Liver and serum samples were collected at each time point for further analysis. The results demonstrated that fasting obviously decreased the liver size accompanying with hepatic lipid accumulation, which were all returned to normal level after refeeding. Lipidomics analysis revealed that a total of 309 lipids were significantly disturbed, over half of them belonged to triacylglycerol (TG). Consistently, fasting significantly altered the expression of genes associated with fatty acid uptake, TG synthesis and metabolism, which were returned to baseline level after refeeding. In conclusion, these findings demonstrated that fasting induced liver shrinkage and the change of lipid profiling, especially TG accumulation in liver, while these effects can be reversed after refeeding.