LRH-1 Mitigates Intestinal Inflammatory Disease by Maintaining Epithelial Homeostasis and Cell Survival

Abstract

Epithelial dysfunction and loss of intestinal crypts are defining features of inflammatory bowel disease (IBD). However, current therapies primarily target the immune system and not the epithelium. The nuclear receptor LRH-1 encoded by Nr5a2 is expressed in intestinal epithelium and is thought to contribute to epithelial renewal. Here we investigate how loss and gain of LRH-1 impacts the intestinal epithelium in healthy and inflammatory conditions. Knocking out LRH-1 in murine intestinal organoids reduces Notch signaling, increases crypt cell death and weakens the epithelial barrier. Loss of LRH-1 also distorts the cellular composition of the epithelium, resulting in an expansion of Paneth and goblet cells, and a decrease in enteroendocrine cells. Human LRH-1 (hLRH-1) not only rescues epithelial integrity, but when overexpressed, mitigates inflammatory damage in mouse and human intestinal organoids, including those from IBD patients. Finally, hLRH-1 greatly reduces disease severity in a mouse model of T cell-mediated colitis. Together with the failure of a ligand-incompetent hLRH-1 mutant to protect against TNF-damage, these findings provide compelling evidence that hLRH-1 mediates epithelial homeostasis and is an attractive target for intestinal disease.