布拉氏酵母菌对NEC新生鼠肠组织IL-10、TNF-α和iNOS表达的影响

Effect of Saccharomyces boulardii on expression of IL-10, TNF-α and iNOS in neonatal mice with necrotizing enterocolitis

目的探讨布拉氏酵母菌(SB)对坏死性小肠结肠炎(NEC)新生鼠肠组织炎症因子IL-10、TNF-α、诱导型一氧化氮合酶(iNOS)表达的影响。方法 64只新生鼠随机分为4组,每组16只,正常对照组(母鼠喂养并不给予任何干预)、人工喂养组(仅给予人工喂养)、NEC组(人工喂养+缺氧复氧冷刺激+脂多糖灌胃)、NEC+SB组(在NEC模型组基础上加SB干预,剂量为800mg·kg^(-1)·d^(-1),灌胃1次/d,连用3d)。HE染色、病理评分评估回盲部肠组织损伤程度;Western blot、RT-PCR法检测结肠组织IL-10、TNF-α、iNOS蛋白和mRNA表达水平。结果与正常对照组比较,人工喂养组新生鼠回盲部肠组织病理评分略有升高,NEC组病理评分明显升高,而NEC+SB组病理评分较NEC组降低;人工喂养组和NEC组新生鼠结肠组织IL-10、TNF-α、iNOS蛋白和mRNA表达水平均升高,NEC+SB组IL-10、TNF-α、iNOS蛋白和mRNA表达水平较人工喂养组和NEC模型组均降低(均P<0.05)。结论 SB或通过降低NEC新生鼠肠组织炎症因子IL-10、TNF-α和iNOS的表达水平,减轻肠组织损伤。

Objective To explore the effect of Saccharomyces boulardii（SB） on the expression of interleukin-10（IL-10）, tumor necrosis factor-α（TNF-α） and induced nitric oxide synthase（iNOS） in neonatal mice with necrotizing enterocolitis（NEC）. Methods Sixty four newborn mice were divided to 4 groups with 16 mice in each group： the control group（with breast feeding）, the formula feeding group（formula feeding alone）, the NEC group（cold exposure＋hypoxic-reoxygen treatment＋LPS intragastric administration）, NEC＋SB group（cold exposure＋hypoxic-reoxygen treatment＋LPS intragastric administration and SB 800 mg·kg^-1·d^-1 for 3 d）. The mice were sacrificed, the proximal intestines of ileocecal junction were harvested. The tissue samples were examined by HE staining for pathological scoring, and the expression of IL-10, TNF-α and iNOS protein and mRNA was detected by Western blot and RT-PCR assay, respectively. Results Compared with the control group, the pathological scores were higher in the formula feeding group, and those in NEC group were the highest among 4 groups（P〈0.05）; however,the pathological scores in the NEC＋SB group were lower than NEC group. The expression of IL-10, TNF-α and iNOS protein and mRNA in NEC＋SB group was lower than that in NEC group（P〈0.05）. Conclusion SB can decrease the expression level of IL-10, TNF-α and iNOS in neonatal mice with NEC, and reduce the intestinal tissue damage.