An inulin-type fructan from Codonopsis pilosula ameliorates cyclophosphamide-induced immunosuppression and intestinal barrier injury in mice

In the present study, an inulin-type fructan (ITF) with the degree polymerization (DP) of 21 was isolated from Codonopsis pilosula roots and its structure was characterized by FT-IR, MALDI-TOF-MS and NMR. The immunomodulatory and intestinal protective effects of ITF were investigated on immunosuppressive mice. Male BALB/c mice were pretreated with cyclophosphamide (Cy) for 3 days to establish an immunosuppressive model followed by ITF treatment. The results demonstrated that compared with the model group, ITF administration significantly increased immune organ index (P<0.05), alleviated intestinal villus damage, stimulated serum cytokine secretion including Ig G, IL-4, IL-6, IL-2, TNF-α, and INF-γ (P<0.05), upregulated the expression of Occludin and Claudin-1 (P<0.05), and increased CD4⁺ and CD8⁺ T cells of ileum in Cy-induced mice (P<0.05). Furthermore, ITF restored the intestinal microbiota dysbiosis caused by Cy by increasing the abundance of Muribaculaceae, Blautia, Odoribacter, Lactobacillus and decreasing the abundance of Lachnospiraceae_NK4A136_group (P<0.05). Meanwhile, ITF increased the production of short-chain fatty acids (SCFAs) including acetic acid, propionic acid and butyric acid (P<0.05). These results indicated that ITF can ameliorate cyclophosphamide-induced immunosuppression and intestinal barrier injury, and restore gut microbiota dysbiosis. This study provided important evidences for the immunomodulatory and intestinal protective effects of the ITF from C. pilosula.

Codonopsis pilosula; Immunomodulatory effects; Intestinal microbiota; Inulin-type fructan; Short-chain fatty acids.