Se/GSH-enriched Candida utilis ameliorates DSS-induced colitis in mice by preventing oxidative stress and improving immune responses

Selenium (Se) and glutathione (GSH) possess anti-inflammatory and antioxidant properties. Candida utilis has a high capacity for Se and GSH enrichment and it is beneficial to intestinal health; however, the impact of Se/GSH-enriched C. utilis on colitis is still not well understood. The present study aimed to assess the preventive and ameliorative effects of Se/GSH-enriched C. utilis SE-172 on colitis in mice. Selenized yeast effectively alleviated weight loss, inhibited colon shortening, reduced disease activity index, and decreased histological damage in mice with colitis. Supplementation with medium and high doses of selenized yeast significantly increased the activities of catalase, superoxide dismutase, and glutathione peroxidase, as well as interleukin-10 levels. Concurrently, it significantly decreased the levels of malondialdehyde and myeloperoxidase. Moreover, treatment with selenized yeast reduced apoptosis in colonic epithelial cells, downregulated the expression of interleukin-6, interleukin-1β, and interferon-gamma genes, and improved the immune response by modulating the proportions of innate immune cells. Selenized yeast also inhibited activation of the nuclear transcription factor-κB signaling pathway, attenuated intestinal barrier damage, and promoted the synthesis of short-chain fatty acids in the colon. Selenized C. utilis may thus have preventive and ameliorative effects on colitis by reducing the colonic inflammatory response and alleviating oxidative damage. These findings provide strong evidence for the development and application of Se/GSH-enriched C. utilis as a dietary treatment for colitis.