Riol Claudia Da, Dietrich Richard, Märtlbauer Erwin, Jessberger Nadja
Department of Veterinary Sciences, Faculty of Veterinary Medicine, Ludwig-Maximilians-Universität München, Munich, Germany.
Front Microbiol. 2018 Aug 17;9:1946. doi: 10.3389/fmicb.2018.01946. eCollection 2018.
Enteropathogenic cause diarrhea due to the production of enterotoxins in the intestine. To start this process, spores have to be ingested together with contaminated food and survive the stomach passage. In this study, the influence of consumed foodstuffs on spore survival as well as on cytotoxicity toward colon epithelial cells was investigated. Spore survival of 20 enteropathogenic and apathogenic strains during simulated stomach passage was highly strain-specific and did not correlate with the toxic potential. Survival of three tested strains was strain-specifically altered by milk products. Whereas milk, a follow-on formula and rice pudding had only little influence, spores seemed to be protected by milk products with high fat content such as whipped cream and mascarpone. Furthermore, tested milk products decreased the toxic activity of three strains toward CaCo-2 cells. Investigating the individual components, lactoferrin, a skim milk powder and vitamins C, B5 and A showed the most inhibiting effects. On the other hand, biotin, vitamin B3 and another skim milk powder even enhanced cytotoxicity. Further studies suggested that these inhibiting effects result only partially from inhibiting cell binding, but rather from blocking the interaction between the single enterotoxin components.
肠道致病菌通过在肠道内产生肠毒素而导致腹泻。要启动这一过程,孢子必须与受污染的食物一起被摄入,并在通过胃部时存活下来。在本研究中,研究了食用食物对孢子存活以及对结肠上皮细胞细胞毒性的影响。20株肠道致病菌和非致病性菌株在模拟胃部通过过程中的孢子存活情况具有高度菌株特异性,且与毒性潜力无关。三种受试菌株的存活情况因乳制品而发生菌株特异性改变。牛奶、后续配方奶粉和米布丁的影响较小,而高脂肪含量的乳制品如鲜奶油和马斯卡彭奶酪似乎能保护孢子。此外,受试乳制品降低了三种菌株对CaCo-2细胞的毒性活性。研究单个成分时,乳铁蛋白、脱脂奶粉以及维生素C、B5和A显示出最大的抑制作用。另一方面,生物素、维生素B3和另一种脱脂奶粉甚至增强了细胞毒性。进一步的研究表明,这些抑制作用仅部分源于抑制细胞结合,而更多地源于阻断单一肠毒素成分之间的相互作用。