Department of Internal Medicine, National Defense Medical College, Saitama, Japan.
Graduate School, International University of Health and Welfare, Tokyo, Japan.
J Gastroenterol Hepatol. 2020 Jan;35(1):110-117. doi: 10.1111/jgh.14808. Epub 2019 Oct 16.
Dietary emulsifiers are widely used in processed foods and officially approved as safe for intake. However, recent studies have demonstrated that some emulsifiers alter the colonic microbiota, leading to colonic low-grade inflammation, in mice. The effect of dietary emulsifiers on small-intestinal microbiota, which is important for gut immunity, has not been studied. We aimed to investigate the effect of a representative dietary emulsifier, polysorbate-80 (P80), on the small-intestinal microbiota in normal mice.
Some mice were pretreated with P80 for 8 weeks with or without indomethacin administration on the last 2 days, and intestinal damage was evaluated histologically. The ileal and colonic microbiota composition was assessed using 16S rRNA polymerase chain reaction.
Polysorbate-80 increased the Gammaproteobacteria abundance and decreased the α-diversity in the small intestine. No decrease in α-diversity was observed in the colon. P80 pretreatment exacerbated the indomethacin-induced small-intestinal lesions and significantly increased the interleukin-1β expression. Culture of ileal content on deoxycholate hydrogen sulfide lactose agar showed that P80 significantly increased the colonies of the sulfide-producing bacteria Proteus spp. (genetically identified as Proteus mirabilis). Antibiotic pretreatment abolished the P80-induced aggravation of indomethacin-induced ileitis. Motility assay in semisolid agar showed that adding 0.02% P80 to the agar significantly increased the diameter of P. mirabilis colonies but not that of Escherichia coli colonies.
Polysorbate-80 enhances the vulnerability of the small intestine to indomethacin-induced injury by inducing ileal dysbiosis. Direct enhancement of the motility of specific flagellated microbiota by P80 might be related to dysbiosis and intestinal injury.
食品中广泛使用的膳食乳化剂被官方批准为安全可食用。然而，最近的研究表明，一些乳化剂会改变结肠微生物群，导致小鼠结肠低度炎症。膳食乳化剂对肠道免疫至关重要的小肠微生物群的影响尚未研究。我们旨在研究代表性膳食乳化剂聚山梨酯 80（P80）对正常小鼠小肠微生物群的影响。
一些小鼠用 P80 预处理 8 周，最后 2 天给予或不给予吲哚美辛，评估肠道损伤的组织学表现。采用 16S rRNA 聚合酶链反应评估回肠和结肠微生物群组成。
聚山梨酯 80 增加了肠道 γ-变形菌的丰度，降低了小肠的 α-多样性。在结肠中未观察到 α-多样性降低。P80 预处理加剧了吲哚美辛引起的小肠损伤，显著增加了白细胞介素 1β 的表达。脱氧胆酸-硫化氢-乳糖琼脂上的回肠内容物培养表明，P80 显著增加了产硫菌变形杆菌属（鉴定为奇异变形杆菌）的菌落。抗生素预处理消除了 P80 诱导的吲哚美辛诱导的回肠炎加重。半固体琼脂中的运动性测定表明，在琼脂中添加 0.02% P80 显著增加了奇异变形杆菌菌落的直径，但不增加大肠杆菌菌落的直径。
聚山梨酯 80 通过诱导回肠菌群失调，增加了小肠对吲哚美辛诱导损伤的易感性。P80 对特定鞭毛菌群运动性的直接增强可能与菌群失调和肠道损伤有关。
