Peroxisome proliferator-activated receptors in inflammatory bowel disease: linking immunometabolism, lipid signaling, and therapeutic potential

Inflammatory bowel disease (IBD), encompassing Crohn's disease (CD) and ulcerative colitis, is a chronic condition marked by immune dysregulation, genetic predisposition, and metabolic disturbances. Emerging evidence highlights the role of lipid metabolism and peroxisome proliferator-activated receptor (PPAR) signaling in modulating immune responses in IBD. PPAR-γ and PPAR-α regulate macrophage polarization, T-cell differentiation, and epithelial barrier integrity, influencing disease severity and progression. Alterations in PPAR activity contribute to metabolic stress and inflammation, linking IBD pathophysiology to immunometabolism. Studies suggest that targeting PPARs may mitigate inflammation through modulation of cytokine production, immune cell function, and gut microbiota interactions. In this review, we focus specifically on CD and explore how PPAR signaling intersects with mesenteric adipose tissue dysfunction and microbial dysbiosis, 2 hallmark features of CD. PPAR agonists, already used in metabolic-inflammatory diseases such as metabolic-associated liver disease, have demonstrated antiinflammatory effects in experimental colitis models. Translating these findings into clinical applications could offer novel treatment strategies for CD. Future research should focus on clinical trials, genetic studies, and microbiota-targeted approaches to elucidate PPAR-driven mechanisms in CD pathogenesis. Understanding the interplay between PPARs, lipid metabolism, and immune responses may lead to innovative therapeutic strategies, improving disease management and patient outcomes.