Whole king oyster mushroom (Pleurotus eryngii) alleviates high-fat diet-induced low-grade colonic inflammation in association with the gut microbiota-barrier-immune axis.

Whole food-based dietary strategies have attracted increasing attention for their role in preventing metabolic disorders. This study investigated the effects of whole Pleurotus eryngii (WPE) on high-fat diet (HFD)-induced low-grade colonic inflammation in mice, with a focus on the gut microbiota-barrier-immune axis. WPE supplementation attenuated HFD-induced body weight gain, improved colonic histopathology, and enhanced mucus production with increased goblet cell abundance and mucin expression, alongside restoration of epithelial barrier-related proteins and genes. WPE attenuated mucosal immune activation by reducing immune cell infiltration and rebalancing cytokines. Gut microbiota analysis revealed that WPE reversed HFD-induced dysbiosis and was associated with changes in microbial metabolic potential, especially by potentially enhancing short-chain fatty acid-related pathways, suppressing pro-inflammatory microbial activities, and enriching mucin-associated taxa. Our findings demonstrate that WPE alleviates HFD-induced low-grade colonic inflammation by coordinating improvements in gut microbial composition, intestinal barrier, and mucosal immunity, highlighting the potential of whole-mushroom-based strategies for maintaining intestinal homeostasis under obesogenic conditions.