Nondigestible oligosaccharides enhance bacterial colonization resistance against Clostridium difficile in vitro
Nondigestible oligosaccharides enhance bacterial colonization resistance against Clostridium difficile in vitro
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DOI：
10.1128/aem.69.4.1920-1927.2003
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发表时间：
2003-04-01
影响因子：
4.4
通讯作者：
Macfarlane, GT
中科院分区：
文献类型：
--
作者：
Hopkins, MJ;Macfarlane, GT
艰难梭菌是伪膜性结肠炎的主要病原体，也是院内抗生素相关性腹泻的主要原因。使用益生菌在控制艰难梭菌感染方面取得了有限的成功；然而，益生元也可用于改变大肠道中的细菌群落结构和代谢，尽管这些碳水化合物对抑制梭菌病原体的作用尚未得到很好的表征。本研究的目的是利用培养和分子技术，研究三种不易消化的寡糖 (NDO) 制剂在体外正常和抗生素处理的粪便微生物群中的双歧原性，以及它们增强对艰难梭菌定植的屏障抵抗力的能力。来自三名健康志愿者的粪便培养物受到艰难梭菌产毒菌株的攻击，并使用分子探针监测病原体的生长，以及一段时间内双歧杆菌和拟杆菌种群的生长。通过测定活细菌计数、短链脂肪酸形成和细胞毒性活性来评估定植抗性的证据。然后进行恒化器研究以确定双歧杆菌和艰难梭菌抑制之间是否存在直接相关性。 NDO 被证明可以刺激双歧杆菌生长，同时艰难梭菌数量也会减少。然而，在克林霉素存在的情况下，NDO 存在时抗双歧杆菌的活性增强，导致定植抗性进一步丧失。在没有克林霉素的情况下，NDO 增强了对艰难梭菌的定植抗性，尽管这不能归因于双歧杆菌诱导的抑制现象。
Clostridium difficile is the principal etiologic agent of pseudomembranous colitis and is a major cause of nosocomial antibiotic-associated diarrhea. A limited degree of success in controlling C difficile infection has been achieved by using probiotics; however, prebiotics can also be used to change bacterial community structure and metabolism in the large gut, although the effects of these carbohydrates on suppression of clostridial pathogens have not been well characterized. The aims of this study were to investigate the bifido-genicity of three nondigestible oligosaccharide (NDO) preparations in normal and antibiotic-treated fecal microbiotas in vitro and their abilities to increase barrier resistance against colonization by C difficile by using cultural and molecular techniques. Fecal cultures from three healthy volunteers were challenged with a toxigenic strain of C difficile, and molecular probes were used to monitor growth of the pathogen, together with growth of bifidobacterial and bacteroides populations, over a time course. Evidence of colonization resistance was assessed by determining viable bacterial counts, short-chain fatty acid formation, and cytotoxic activity. Chemostat studies were then performed to determine whether there was a direct correlation between bifidobacteria and C. difficile suppression. NDO were shown to stimulate bifidobacterial growth, and there were concomitant reductions in C. difficile populations. However, in the presence of clindamycin, activity against bifidobacteria was augmented in the presence of NDO, resulting in a further loss of colonization resistance. In the absence of clindamycin, NDO enhanced colonization resistance against C. difficile, although this could not be attributed to bifidobacterium-induced inhibitory phenomena.