Liver Med23 ablation improves glucose and lipid metabolism and prevent diet-induced obesity. Mus musculus

Mediator complex function as an integrative hub for transcriptional regulation. Here we show that Mediator subunit MED23 regulate glucose and lipid metabolism via FOXO1 in liver. Here, we have generated a liver-specific Med23-knockout (LMKO) mouse and found that Med23-deletion in liver improved glucose and lipid metabolism, as well as insulin responsiveness, and prevented diet-induced obesity. Mechanistically, MED23 participated in gluconeogenesis and cholesterol synthesis by interacting with FOXO1. Disruption of this interaction by hepatic Med23-deletion impaired the Mediator and RNAP II recruitment and partially reduced the expression of the FOXO1 target genes. Remarkably, acute hepatic Med23 knockdown in db/db mice significantly improved insulin sensitivity. Overall, our data revealed Mediator MED23 as a critical regulator of glucose and lipid metabolism, suggesting novel therapeutic strategies against metabolic diseases. Overall design: Comparison of mRNA expression profile of control and LMKO mice fasted 24 h (fasted) or fasted 24 h then re-fed 24 h (re-fed) (n = 2 per group)