Berberrubine, a Metabolite of Berberine, Attenuates Intestinal Barrier Dysfunction in Inflammatory Bowel Disease by Inhibiting STAT3

Inflammatory bowel disease (IBD) is characterized by intestinal barrier dysfunction and excessive inflammation, in which STAT3 signaling plays a critical role. Berberine is clinically effective against colitis; its application is limited by low bioavailability and toxicity. Berberrubine, a major metabolite of berberine, exhibits improved pharmacological properties; however, its therapeutic potential in IBD remains unclear. The efficacy and mechanisms of berberine and berberrubine were evaluated in DSS-induced colitis mice, LPS-stimulated cells and intestinal organoids. STAT3 knockout cell lines were generated using CRISPR-Cas9 to assess the role of STAT3 in mediating the pharmacological activities of both compounds. We found that berberrubine significantly alleviated colitis, reduced pro-inflammatory cytokines (IL-6 and TNF-α), and restored intestinal barrier integrity by upregulating ZO-1 and claudin-1 in vivo and in organoids, demonstrating superior efficacy and safety to berberine. Mechanistically, both compounds inhibited STAT3 activation and nuclear translocation. STAT3 deficiency attenuated their anti-inflammatory, anti-tumor, and barrier-protective effects. Notably, berberrubine exhibited selective cytotoxicity to cancer cells over normal epithelial cells, suggesting a favorable therapeutic window. Collectively, berberrubine ameliorates intestinal barrier dysfunction and inflammation through inhibition of the STAT3 signaling pathway. Its superior efficacy and favorable safety profile compared to berberine support its potential as a novel therapeutic agent for IBD.