Obesity impairs gut repair via AFABP-mediated iron overload in intestinal stem cells.

Obesity impairs the function of multiple organs, but its effect on gut regeneration remains poorly defined. Here, we show that adipocyte fatty acid-binding protein (AFABP), an adipokine involved in fatty acid transport, impedes intestinal repair by disrupting iron homeostasis in intestinal stem cells (ISCs). Mechanistically, elevated AFABP secretion in obesity binds to plasma transferrin, leading to iron accumulation in ISCs. This accumulation disrupts peroxisome-mediated ISC differentiation, which is essential for intestinal repair following injury. Notably, AFABP overexpression in adipocytes of lean mice impedes ISC differentiation and gut repair. Conversely, AFABP depletion or the administration of AFABP inhibitors, iron chelators or peroxisome activators effectively mitigates colitis in obese animals. Overall, our findings reveal a mechanistic link between obesity and intestinal repair, and identify the adipose-gut axis as a therapeutic target for obesity-associated intestinal disorders.