In vivo immunostimulatory activity of Centella asiatica extract on the intestinal immune system in native C3H/HeN mice

BACKGROUND In our previous study, we demonstrated the colitis‐alleviating effects of Centella asiatica hot‐water extract (CA‐HE) in an inflammatory bowel disease mouse model. In this study, we aimed to demonstrate its potential to activate intestinal immunity via Peyer's patch (PP)‐mediated mechanisms and serve as a functional agent for maintaining intestinal immune homeostasis. RESULTS Four‐week oral administration of CA‐HE induced no toxicological effects and significantly upregulated hematopoietic (interleukin‐4, ‐6, and granulocyte–macrophage colony‐stimulating factor) and immunoglobulin A (IgA)‐inducing (IL‐10 and tumor growth factor‐β) factors derived from PPs. These immunological changes were also observed in the ileum and serum, contributing to bone marrow cell proliferation. In addition, CA‐HE promoted IgA production in the PPs, ileum, serum, and feces. Histological analysis further revealed an increased number and size of germinal centers. Finally, CA‐HE beneficially modulated the intestinal environment by increasing cecal short‐chain fatty acid levels. CONCLUSION Our results demonstrate that CA‐HE activates the intestinal immune system via PP‐mediated immunomodulation. Taken together, the findings indicate that CA‐HE may serve as a multifunctional agent for use in functional foods or pharmaceuticals that aim to maintain intestinal immune homeostasis.