Ruxolitinib Alleviates Inflammation, Apoptosis, and Intestinal Barrier Leakage in Ulcerative Colitis via STAT3.

Area of Science:

• Gastroenterology
• Immunology
• Pharmacology

Background:

• Ulcerative colitis (UC) is a chronic inflammatory disorder of the colon with increasing prevalence and limited treatment options.
• Ruxolitinib, a Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) inhibitor, has emerged as a potential therapeutic agent for colitis.

Purpose of the Study:

• To investigate the therapeutic potential of Ruxolitinib in preclinical models of ulcerative colitis.
• To elucidate the underlying mechanisms by which Ruxolitinib exerts its protective effects against colitis.

Main Methods:

• Established in vivo (mouse model) and in vitro (colonic epithelial cell) colitis models.
• Administered Ruxolitinib and assessed therapeutic efficacy through various biological assays, including histology, immunohistochemistry, Western blotting, and cytokine analysis.
• Manipulated STAT3 expression using siRNA and overexpression plasmids to determine its role in Ruxolitinib's mechanism of action.

Main Results:

• Ruxolitinib treatment significantly alleviated colitis symptoms and severity in both in vivo and in vitro models.
• Mechanistically, Ruxolitinib attenuated nuclear factor kappa B (NF-κB)-induced inflammation, reduced apoptosis, and improved epithelial barrier function.
• STAT3 signaling pathway was confirmed to be involved, as STAT3 knockdown partially reversed Ruxolitinib's protective effects, while overexpression enhanced its anti-inflammatory actions.

Conclusions:

• Ruxolitinib demonstrates significant therapeutic efficacy in preclinical models of ulcerative colitis.
• The drug alleviates colitis by inhibiting NF-κB-mediated inflammation and apoptosis while restoring epithelial barrier integrity, partly through STAT3 modulation.
• Ruxolitinib represents a novel therapeutic strategy for managing ulcerative colitis.