Research Institute, Hospital for Sick Children, University of Toronto, Canada.
J Infect Dis. 2012 Jul 1;206(1):99-109. doi: 10.1093/infdis/jis177. Epub 2012 Mar 19.
Probiotics prevent disease induced by Citrobacter rodentium, a murine-specific enteric pathogen. Whether probiotics can be used to interrupt the infectious process following initiation of infection was determined.
C57BL/6 adult and neonatal mice were challenged with C. rodentium, and a probiotic mixture containing Lactobacillus helveticus and Lactobacillus rhamnosus was provided 1 week before bacterial challenge, concurrently with infection, or 3 days and 6 days after infection. Mice were sacrificed 10 days after infection, and disease severity was assessed by histological analysis and in vivo intestinal permeability assay. Inflammatory pathways and the composition of the fecal microbiome were assessed in adult mice.
Preadministration and coadministration of probiotics ameliorated C. rodentium-induced barrier dysfunction, epithelial hyperplasia, and binding of the pathogen to host colonocytes in adults, with similar findings in neonatal mice. Upregulated tumor necrosis factor α and interferon γ transcripts were suppressed in the pretreated probiotic group, whereas interleukin 17 transcription was suppressed with probiotics given up to 3 days after infection. Probiotics promoted transcription of interleukin 10 and FOXP3, and increased follicular T-regulatory cells in pretreatment mice. C. rodentium infection resulted in an altered fecal microbiome, which was normalized with probiotic intervention.
This study provides evidence that probiotics can prevent illness and treat disease in an animal model of infectious colitis.
益生菌可预防肠道致病菌柠檬酸杆菌引起的疾病。本研究旨在确定益生菌是否可用于阻断感染起始后的感染过程。
C57BL/6 成年和新生鼠感染柠檬酸杆菌，在细菌攻毒前 1 周、攻毒时、攻毒后 3 天和 6 天给予含瑞士乳杆菌和鼠李糖乳杆菌的益生菌混合物。感染 10 天后处死小鼠，通过组织学分析和体内肠道通透性测定评估疾病严重程度。评估成年鼠的炎症通路和粪便微生物组组成。
益生菌的预处理和共同给药可改善柠檬酸杆菌诱导的成年鼠和新生鼠的屏障功能障碍、上皮增生和病原体与宿主结肠细胞的结合，在新生鼠中也有类似的发现。预处理益生菌组中上调的肿瘤坏死因子 α 和干扰素 γ 转录本被抑制，而在感染后 3 天内给予益生菌可抑制白细胞介素 17 的转录。益生菌可促进预处理小鼠白细胞介素 10 和 FOXP3 的转录，并增加滤泡性 T 调节细胞。柠檬酸杆菌感染导致粪便微生物组发生改变，益生菌干预可使其正常化。
本研究为益生菌可预防感染性结肠炎动物模型中的疾病提供了证据，并可进行治疗。
