Fucoidan Oligosaccharides from Kjellmaniella crassifolia Ameliorate Ulcerative Colitis by Regulating the TLR4 and NF-κB Signaling Pathway and Modulating Gut Microbiota

作者：Xu Z, Jia Z, Li L, Zeng F, Sun J, Ma Y, Shi W, Liu S, He Y, Wang Q, Ren D · 发表于：Marine drugs · 年份：2026 · DOI：10.3390/md24050186 · 被引用次数：79 · 研究领域：Colitis, Ulcerative、Polysaccharides、Oligosaccharides、Gastrointestinal Microbiome、Animals、Toll-Like Receptor 4、Signal Transduction、NF-kappa B、Mice、Disease Models, Animal、Male、Dextran Sulfate

Ulcerative colitis (UC) is a form of inflammatory bowel disease (IBD), which is marked by severe abdominal pain, weight loss, perianal bleeding, and diarrhea. This study successfully isolated and purified four low-molecular-weight fucoidan oligosaccharides through acid hydrolysis and Bio Gel P10 gel filtration. The molecular weights were 2.9 × 104-1.36 × 105 Da, 182-1012 Da, 161-939 Da and 161-939 Da, respectively. A mouse model of colitis was induced using Dextran Sulfate Sodium (DSS). The results indicated that fucoidan and fucoidan oligosaccharides could ameliorate murine ulcerative colitis, with the oligosaccharides (200 mg/kg/d) demonstrating superior therapeutic effects. This superiority was likely attributed to the lower molecular weight and higher content of total sugars and fucose. The primary mechanisms involved the modulation of gene and protein expression levels associated with the Toll-like receptor 4, Myeloid differentiation primary response 88, nuclear factor kappa-light-chain-enhancer of activated B cells, p65, and Inhibitor of kappa light polypeptide gene enhancer in B cells, alpha (TLR4, MYD88, NF-κB p65, and IκB-α) signaling pathways, which reduce the production of inflammatory cytokines such as tumor necrosis factor-alpha, Interleukin-1 beta and Interleukin-6 (TNF-α, IL-1β, and IL-6). Additionally, these oligosaccharides alleviated oxidative stress, enhanced the levels of intestinal barrier proteins (Claudin family member 4 and Zonula occludens protein 1),...