Effect of RXRα agonist bexarotene on gene expression in hepatocytes of hepatic RXRα knockout mice

Retinoid X receptor alpha (RXRα) is a ligand-activated nuclear receptor involved in the regulation of retinoid metabolism. RXRα activation by agonist bexarotene can significantly induce hepatomegaly and promote liver regeneration after 70% partial hepatectomy (PHx) in wild type mice, while these effects were abolished in liver-specific RXRα-knockout mice. However, the underlying mechanisms remain unclear. Our findings reveal that RXRα activation promotes liver proliferation through transactivation of Cyclin D1. These data raise some key questions for understanding the manipulation of liver size and liver regeneration by RXRα agonists.