植物乳杆菌NCU137发酵薏苡仁调节免疫抑制小鼠免疫和肠道黏膜屏障功能

Adlay Seeds Fermented by Lactobacillus plantarum NCU137 Regulates Immunity and Intestinal Mucosal Barrier Function in Immunosuppressed Mice

目的:比较植物乳杆菌NCU137发酵前后薏苡仁对环磷酰胺诱导免疫抑制小鼠的免疫和肠道黏膜屏障功能的调节作用。方法:BALB/c小鼠随机分为正常组、模型组、发酵薏苡仁组和未发酵薏苡仁组,造模前7 d分别每天灌胃0.2 mL生理盐水、发酵薏苡仁和未发酵薏苡仁,连续干预10 d;最后3 d每日腹腔注射100 mg/kg环磷酰胺,建立免疫抑制小鼠模型,正常组腹腔注射等体积生理盐水。检测小鼠脾脏指数、脾脏淋巴细胞亚群数量、细胞因子和免疫球蛋白含量,观察小肠病理组织,分析其黏膜屏障功能。结果:与模型组相比,发酵薏苡仁可显著增加免疫低下小鼠脾脏和胸腺指数,上调脾脏t淋巴细胞亚群白细胞分化抗原(cluster of differentiation, CD)4^(+)/CD8^(+)比值,下调脾脏促炎细胞因子肿瘤坏死因子α水平,升高血清免疫球蛋白M和免疫球蛋白G水平,修复小肠黏膜结构和上调闭合蛋白(Occludin)和钙黏蛋白E(E-cadherin)基因的表达,其效果优于未发酵薏苡仁。结论:植物乳杆菌NCU137发酵薏苡仁具有调节免疫和肠道黏膜屏障功能的潜力,有望开发成一种新型的具有免疫调节功能的健康食品。

Objective:to compare the regulatory effects of adlay(Coix lachryma-jobi L.)seeds fermented and not fermented by Lactobacillus plantarum NCU137 on immune and intestinal mucosal barrier function in mice induced by cyclophosphamide(CtX).Methods:BALB/c mice were randomly divided into four groups,including normal,CtX-induced model,non-fermented adlay seed(NFC)and fermented adlay seed(FC)treatment.the mice in the normal and CtX groups were orally administrated with 0.2 mL of physiological saline for 10 days,while those in the NFC and FC groups 0.2 mL of non-fermented and fermented adlay seeds for 10 days,respectively.the immunosuppressed mouse model was established by daily intraperitoneal injection of 100 mg/kg of CtX for the last three days of the administration period,while the normal group was intraperitoneally injected with the same volume of normal saline.Spleen index,the number of spleen t lymphocyte subsets,and the levels of cytokines and immunoglobulin were measured,histopathological examination of the small intestine was performed and intestinal mucosal barrier function was detected.Results:Compared with the CtX group,fermented adlay seeds significantly increased the spleen and thymus indexes of immunosuppressed mice,up-regulated the cluster of differentiation(CD)4^(+)/CD8^(+)ratio of spleen t lymphocytes,down-regulated the levels of spleen pro-inflammatory cytokines such as tumor necrosis factor-α(tNF-α),and increased serum immunoglobulin(Ig)M and IgG levels.Moreover,fermented adlay seeds repaired small intestinal mucosal structure and up-regulated the gene expression of Occludin and E-cadherin,and the effect was more pronounced than that of non-fermented adlay seeds.Conclusion:Coix lachryma-jobi L.seeds fermented by L.plantarum NCU137 have the potential to regulate immune and intestinal mucosal barrier function,which are expected to be developed into a novel health food with immunomodulatory function.