AI-Powered Discovery of Rosmarinic Acid as a Novel Ferroptosis Inhibitor for Ulcerative Colitis via Targeting the ALOX15-VDAC1 Axis.

Ulcerative colitis (UC) is a chronic inflammatory bowel disease with limited mechanism-based therapies, and ferroptosis-an iron-dependent lipid peroxidation-driven cell death-has emerged as a critical pathogenic event. Using a machine learning model that combines molecular fingerprints and transfer learning representations to screen for ALOX15 inhibitors, we identified rosmarinic acid (RA) from natural product libraries. RA exhibited high-affinity binding to ALOX15 and maintained stable complex conformation in molecular dynamics simulations. In dextran sulfate sodium-induced colitis mice and lipopolysaccharide-treated intestinal epithelial cells (IEC-6 and mouse colonic epithelial cell), RA alleviated disease activity index, colon shortening, histological damage, and barrier protein loss (ZO-1, Occludin, and Claudin-1). Mechanistically, RA suppressed ferroptosis by restoring GPX4, SLC7A11, and FTH1; reducing ACSL4, COX-2, and lipid reactive oxygen species (ROS); and lowering intracellular Fe2+ and malondialdehyde. Crucially, RA disrupted the ALOX15-VDAC1 protein complex, preserved mitochondrial membrane potential, and reduced mitochondrial ROS, effects that were abrogated by ALOX15 knockdown or VDAC1 knockdown. Serum metabolomics further revealed that RA remodels lipid metabolism pathways (arachidonic acid and linoleic acid metabolism) linked to ferroptosis. Collectively, this artificial intelligence-driven discovery positions RA as a novel ferroptosis inhibitor that targets the ALOX15-VDAC1 axis, offering a promising therapeutic candidate for UC.