Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, ABT6G 2P5, Canada.
Group on the Molecular and Cell Biology of Lipids, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, ABT6G 2E1, Canada.
Br J Nutr. 2021 Jan 14;125(1):50-61. doi: 10.1017/S0007114520002639. Epub 2020 Aug 14.
Dietary choline, which is converted to phosphatidylcholine (PC) in intestinal enterocytes, may benefit inflammatory bowel disease patients who typically have reduced intestinal choline and PC. The present study investigated the effect of dietary choline supplementation on colitis severity and intestinal mucosal homoeostasis using a Citrobacter rodentium-induced colitis model. C57BL/6J mice were fed three isoenergetic diets differing in choline level: choline-deficient (CD), choline-sufficient (CS) and choline-excess (CE) for 3 weeks prior to infection with C. rodentium. The effect of dietary choline levels on the gut microbiota was also characterised in the absence of infection using 16S rRNA gene amplicon sequencing. At 7 d following infection, the levels of C. rodentium in CD mice were significantly greater than that in CS or CE groups (P < 0·05). CD mice exhibited greater damage to the surface epithelium and goblet cell loss than the CS or CE mice, which was consistent with elevated pro-inflammatory cytokine and chemokine levels in the colon. In addition, CD group exhibited decreased concentrations of PC in the colon after C. rodentium infection, although the decrease was not observed in the absence of challenge. Select genera, including Allobaculum and Turicibacter, were enriched in response to dietary choline deficiency; however, there was minimal impact on the total bacterial abundance or the overall structure of the gut microbiota. Our results suggest that insufficient dietary choline intake aggravates the severity of colitis and demonstrates an essential role of choline in maintaining intestinal homoeostasis.
饮食中的胆碱在肠道肠上皮细胞中转化为磷脂酰胆碱(PC),可能有益于炎症性肠病患者,这些患者通常肠道胆碱和 PC 减少。本研究使用柠檬酸杆菌诱导的结肠炎模型,研究了饮食补充胆碱对结肠炎严重程度和肠道黏膜稳态的影响。C57BL/6J 小鼠在感染柠檬酸杆菌之前,用三种等能量的胆碱水平不同的饮食喂养 3 周:胆碱缺乏(CD)、胆碱充足(CS)和胆碱过量(CE)。在没有感染的情况下,还使用 16S rRNA 基因扩增子测序来描述饮食胆碱水平对肠道微生物群的影响。感染后 7d,CD 组小鼠中的柠檬酸杆菌水平明显高于 CS 或 CE 组(P<0·05)。与 CS 或 CE 组相比,CD 组小鼠的表面上皮损伤更大,杯状细胞丢失更多,这与结肠中促炎细胞因子和趋化因子水平升高一致。此外,在感染柠檬酸杆菌后,CD 组小鼠结肠中的 PC 浓度降低,但在没有挑战的情况下未观察到这种降低。包括 Allobaculum 和 Turicibacter 在内的一些特定菌属的丰度因饮食胆碱缺乏而增加;然而,这对总细菌丰度或肠道微生物群的整体结构几乎没有影响。我们的结果表明,饮食中胆碱摄入不足会加重结肠炎的严重程度,并证明胆碱在维持肠道稳态方面的重要作用。