Abstract Polysaccharide is one of the main bioactive substances in Cordyceps sinensis ( C. sinensis ). The aim of this study was to investigate the effect of polysaccharide from natural C. sinensis (CSP) on intestinal mucosal immunity and antioxidant activity in cyclophosphamide (Cy)-induced intestinal immunosuppressed mice, further to explore the potential mechanism. Results showed that in mice with Cy-induced intestinal injury, the supplement of CSP (25, 50, 100 mg/kg·bw) significantly increased the levels of goblet cells and mucus in intestine in a dose-dependent manner. The formation of immunoglobulin A (IgA)-secreting cells and the secretory IgA (sIgA) contents were promoted obviously in CSP groups. Furthermore, CSP significantly promoted the secretion or mRNA expression of T helper (Th) 1 style cytokines, including interleukin-2 (IL-2), IL-12 p40, interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α), in addition to Th1 style transcription factor T-bet. Besides, the levels of Th2 style cytokines, including IL-4, IL-10 and transcription factor GATA-3, were also improved. The value of T-bet/GATA-3, as well as IFN-γ/IL-4 was increased obviously. These results indicated that CSP effectively enhanced intestinal mucosal immunity and regulated polarization of Th1/Th2 cells. The total antioxidant capacity (T-AOC), and the activities of superoxidase dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) in liver were increased significantly, and the content of malondialdehyde (MDA) was decreased dose-dependently. In conclusion, CSP effectively ameliorated Cy-induced intestinal injury in mice, which provided a good suggestion of the potential utilization of CSP as a natural immunopotentiator and antioxidant.

中文翻译：

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天然冬虫夏草多糖改善免疫抑制小鼠肠道损伤并增强抗氧化活性

摘要 多糖是冬虫夏草（C. sinensis）中主要的生物活性物质之一。本研究的目的是研究天然中华绒螯蟹多糖（CSP）对环磷酰胺（Cy）诱导的肠道免疫抑制小鼠肠道粘膜免疫和抗氧化活性的影响，进一步探索其潜在机制。结果表明，在 Cy 诱导的肠道损伤小鼠中，CSP 的补充（25、50、100 mg/kg·bw）以剂量依赖性方式显着增加肠道杯状细胞和粘液的水平。CSP组明显促进免疫球蛋白A（IgA）分泌细胞的形成和分泌性IgA（sIgA）含量。此外，CSP 显着促进 T 辅助 (Th) 1 型细胞因子的分泌或 mRNA 表达，包括白细胞介素 2 (IL-2)、IL-12 p40、干扰素-γ (IFN-γ) 和肿瘤坏死因子-α (TNF-α)，以及 Th1 型转录因子 T-bet。此外，包括 IL-4、IL-10 和转录因子 GATA-3 在内的 Th2 型细胞因子的水平也得到了提高。T-bet/GATA-3、IFN-γ/IL-4值明显升高。这些结果表明CSP有效地增强了肠粘膜免疫并调节了Th1/Th2细胞的极化。肝脏总抗氧化能力（T-AOC）、超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-Px）和过氧化氢酶（CAT）活性显着升高，丙二醛（MDA）含量随剂量降低-依赖。总之，CSP 有效改善了 Cy 诱导的小鼠肠道损伤，