Yam protein ameliorates cyclophosphamide-induced intestinal immunosuppression by regulating gut microbiota and its metabolites

Yam is a dual-purpose crop used in both medicine and food that is commonly used as a dietary supplement in food processing. Since yam proteins are often lost during the production of yam starch, elucidating the functionally active value of yam proteins is an important guideline for fully utilizing yam in industrial production processes. This study aimed to explore the potential protective effect of yam protein (YP) on cyclophosphamide (CTX)-induced immunosuppression in mice. The results showed that YP can reduce immune damage caused by CTX by reversing immunoglobulins (IgA, IgG and IgM), cytokines (TNF-α, IL-6, etc.) in the intestines of mice. Moreover, YPs were found to prevent CTX-induced microbiota dysbiosis by enhancing the levels of beneficial bacteria within the microbiome, such as Lactobacillus, and lowering those of Desulfovibrio_R and Helicobacter_A. Metabolomics analyses showed that YP significantly altered differential metabolites (tryptophan, etc.) and metabolic pathways (ABC transporter protein, etc.) associated with immune responses in the gut. Furthermore, important connections were noted between particular microbiomes and metabolites, shedding light on the immunoprotective effects of YPs by regulating gut flora and metabolism. These findings deepen our understanding of the functional properties of YPs and lay a solid foundation for the utilization of yam.