Extracts of okra mucilage protect intestinal homeostasis through gut microbiota and immune responses.

Okra pods (Abelmoschus esculentus (L.) Moench) are known as a vegetable, the mucilage of which possesses many bioactivities. Okra mucilage (OM) is a carbohydrate-rich natural extract containing polysaccharides and other bioactive components. However, its efficacy under different types of intestinal stress and its comparison with standard therapeutic agents remain unclear. Chemical characterization demonstrated that OM contains abundant carbohydrates and diverse chemical constituents. In this study, we evaluated the protective effects of OM in dextran sulfate sodium (DSS)-induced colitis and fasting-induced intestinal injury models in mice. Mesalazine and GA were used as a positive control in DSS and fasting-induced injury models, respectively. Generally, OM treatment significantly alleviated intestinal pathological damage, restored intestinal barrier integrity, promoted epithelial regeneration, and modulated gut microbial composition in these two models. In DSS-induced colitis, OM increased the abundance of short-chain fatty acid (SCFA)-producing bacterial families Muribaculaceae and Lachnospiraceae, while reducing pro-inflammation-associated Bacteroidaceae, and suppressed key inflammatory genes and factors, including Cxcl1, Cxcl2, Cxcl5, TNF, NF-κB. Notably, the regulatory effects of OM were comparable to mesalazine. In fasting-induced intestinal injury, OM restored microbial balance by regulating taxa such as Enterobacteriaceae and Erysipelotrichaceae, and downregulated gluconeogenesis-related genes including Klf15, Pck1, and Hmgcs2. OM upregulated genes involved in epithelial barrier function and immune homeostasis such as Btnl7, Btnl8, regulating pathways HIF-1, PI3K-Akt, MAPK and glycolysis/gluconeogenesis pathways. These findings demonstrate that OM alleviates intestinal injury by modulating gut microbiota, suppressing inflammation, and restoring intestinal immune and metabolic homeostasis, highlighting its potential as a natural mucilage-derived ingredient for maintaining intestinal homeostasis.