A polysaccharide from Artocarpus heterophyllus Lam. (jackfruit) pulp (JFP-Ps) is known for its excellent bioactivities. However, its impact on small intestinal barrier function is still largely unexplored. The study aimed to examine the protection effect of JFP-Ps against dextran sodium sulfate-induced enteritis and its underlying mechanism. This research revealed that JFP-Ps mitigated small intestinal tissue damage by reducing the expression of pro-inflammatory cytokines and promoting the expression of the anti-inflammatory cytokine interleukin-10 in the small intestine. JFP-Ps diminished oxidative stress by bolstering the activity of antioxidant enzymes and reducing the concentration of malondialdehyde in the small intestine. In addition, JFP-Ps may restore the mechanical barrier and inhibit intestinal structure damage by augmenting the expression of short-chain fatty acids (SCFAs) receptors (GPR41/43) and up-regulating the expression of tight junction proteins (occludin). In conclusion, JFP-Ps may positively influence intestinal health by relieving oxidative stress in the small intestine, improving mechanical barrier function, activating the SCFA-GPR41/GPR43 axis, and inhibiting TLR4/MAPK pathway activation. The results augment our comprehension of the bioactivities of JFP-Ps, corroborating its great potential as a functional food.

Background: Polysaccharides modulate host health by interacting with gut microbiota and reshaping the host–microbial metabolome, potentially facilitating immune regulation. Methods: This study evaluated the modulatory effect of Artocarpus heterophyllus Lam. (jackfruit) polysaccharide (JFP-Ps) against cyclophosphamide (Cy)-induced immunosuppression in mice, focusing on gut microbiota modulation and metabolite changes. Results: JFP-Ps effectively increased the beneficial bacteria ratio, such as Lactobacillus and Lachnospiraceae, while inhibiting some species like Akkermansia. Metabolomic analysis showed that JFP-Ps notably regulated gut microbe-associated metabolites, including short-chain fatty acids (SCFAs), amino acids, bile acids, indoles, and derivatives. These metabolites were involved in various metabolic pathways, including primary bile acid synthesis and biosynthesis of phenylalanine, tyrosine, and tryptophan, along with tryptophan catabolism, purine metabolic processes, and unsaturated fatty acid production. Additionally, significant correlations between microbial groups and functional metabolites were identified. Overall, JFP-Ps exerted an immuno-modulatory effect by reshaping gut microbiota and enhancing co-metabolism with the host. Conclusions: These results provided valuable insights into host–microbiota interactions and gut microbiota-targeted intervention strategies of tropical natural bioactive polysaccharides.

This study investigated the immunoprotective effects of the extract of Vanilla planifolia Andrew (EVPA) on cyclophosphamide (Cy)-induced immunosuppression in mice. The results show that EVPA administration significantly alleviated the immune damage induced by Cy, as evidenced by an improved body weight, organ index, and colonic injury. A further analysis of microbial diversity revealed that the EVPA primarily increased the abundance of the beneficial bacteria Verrucomicrobiota, Lactobacillaceae, and Lactobacillus while decreasing Akkermansiaceae, Akkermansia, Romboutsia, and Lactococcus, thereby ameliorating the microbial dysbiosis caused by Cy. A metabolomic analysis revealed significant alterations in the microbial metabolite levels after EVPA treatment, including urobilinogen, formamidopyrimidine nucleoside triphosphate, Cer (d18:1/18:0), pantetheine, and LysoPC (15:0/0:0). These altered metabolites are associated with pathways related to sphingolipid metabolism, carbapenem biosynthesis, pantothenate and CoA biosynthesis, glycerophospholipid metabolism, and porphyrin metabolism. Furthermore, significant correlations were observed between certain microbial groups and the differential metabolites. These findings provide new insights into the immunomodulatory effects of EVPA on the intestinal microbiota and metabolism, laying the foundation for more extensive utilization.