Research progress in the treatment of ulcerative colitis with natural products

Figure 1 The potential mechanisms of natural products in ameliorating ulcerative colitis through multiple pathways. This schematic diagram illustrates the pathological characteristics of ulcerative colitis (UC) (including intestinal inflammation, barrier impairment, immunological imbalance, reduction-oxidation imbalance, gut dysbiosis, and metabolic disorders) and the therapeutic effects of natural products (NPs) via six core pathways: (1) Direct anti-inflammatory effect; (2) Enhancing intestinal barrier integrity to reverse mucosal impairment; (3) Regulating immune homeostasis to restore immunological balance; (4) Improving antioxidant capacity to reduce reactive oxygen species-mediated damage; (5) Remodeling gut microbiota structure by inhibiting pathogenic bacteria (e.g., Escherichia coli, Klebsiella spp.) and enriching beneficial bacteria (e.g., Firmicutes, Bacteroidetes); and (6) Restoring metabolic homeostasis by modulating gut microbial metabolites (e.g., lipopolysaccharides, short-chain fatty acids). Collectively, NPs exert synergistic effects on multiple pathological links of UC, ultimately alleviating intestinal inflammation and restoring normal gut function. NPs: Natural products; UC: Ulcerative colitis; TNF: Tumor necrosis factor; IL: Interleukin; ROS: Reactive oxygen species; LPS: Lipopolysaccharides; SCFAs: Short-chain fatty acids.