Division of Gastroenterology and Liver Disease, Department of Medicine, School of Medicine, Cleveland, Ohio.
Center for Medical Mycology, Department of Dermatology, School of Medicine, Cleveland, Ohio.
Inflamm Bowel Dis. 2018 Apr 23;24(5):1005-1020. doi: 10.1093/ibd/izy060.
Epidemiological studies indicate that the use of artificial sweeteners doubles the risk for Crohn's disease (CD). Herein, we experimentally quantified the impact of 6-week supplementation with a commercial sweetener (Splenda; ingredients sucralose maltodextrin, 1:99, w/w) on both the severity of CD-like ileitis and the intestinal microbiome alterations using SAMP1/YitFc (SAMP) mice.
Metagenomic shotgun DNA sequencing was first used to characterize the microbiome of ileitis-prone SAMP mice. Then, 16S rRNA microbiome sequencing, quantitative polymerase chain reaction, fluorescent in situ hybridization (FISH), bacterial culture, stereomicroscopy, histology, and myeloperoxidase (MPO) activity analyses were then implemented to compare the microbiome and ileitis phenotype in SAMP with that of control ileitis-free AKR/J mice after Splenda supplementation.
Metagenomics indicated that SAMP mice have a gut microbial phenotype rich in Bacteroidetes, and experiments showed that Helicobacteraceae did not have an exacerbating effect on ileitis. Splenda did not increase the severity of (stereomicroscopic/histological) ileitis; however, biochemically, ileal MPO activity was increased in SAMP treated with Splenda compared with nonsupplemented mice (P < 0.022) and healthy AKR mice. Splenda promoted dysbiosis with expansion of Proteobacteria in all mice, and E. coli overgrowth with increased bacterial infiltration into the ileal lamina propria of SAMP mice. FISH showed increase malX gene-carrying bacterial clusters in the ilea of supplemented SAMP (but not AKR) mice.
Splenda promoted gut Proteobacteria, dysbiosis, and biochemical MPO reactivity in a spontaneous model of (Bacteroidetes-rich) ileal CD. Our results indicate that although Splenda may promote parallel microbiome alterations in CD-prone and healthy hosts, this did not result in elevated MPO levels in healthy mice, only CD-prone mice. The consumption of sucralose/maltodextrin-containing foods might exacerbate MPO intestinal reactivity only in individuals with a pro-inflammatory predisposition, such as CD.
流行病学研究表明,使用人工甜味剂会使克罗恩病(CD)的风险增加一倍。在此,我们使用 SAMP1/YitFc(SAMP)小鼠实验定量评估了商业甜味剂(Splenda;成分蔗糖素麦芽糖糊精,1:99,w/w)补充 6 周对 CD 样回肠炎的严重程度和肠道微生物组改变的影响。
首先使用宏基因组学 shotgun DNA 测序来描述易患回肠炎的 SAMP 小鼠的微生物组。然后,进行 16S rRNA 微生物组测序、定量聚合酶链反应、荧光原位杂交(FISH)、细菌培养、体视显微镜、组织学和髓过氧化物酶(MPO)活性分析,以比较 SAMP 与对照无回肠炎 AKR/J 小鼠的微生物组和回肠炎表型,然后进行 Splenda 补充。
宏基因组学表明,SAMP 小鼠的肠道微生物组表型富含拟杆菌门,实验表明,螺旋杆菌科对回肠炎没有加重作用。Splenda 并未增加(体视显微镜/组织学)回肠炎的严重程度;然而,生物化学分析显示,与未补充的小鼠相比,接受 Splenda 治疗的 SAMP 回肠 MPO 活性增加(P<0.022)和健康的 AKR 小鼠。Splenda 促进了所有小鼠的肠道变形,导致变形菌的扩张,并且 E. coli 过度生长导致 SAMP 小鼠的回肠固有层细菌浸润增加。FISH 显示补充 SAMP 小鼠(但非 AKR 小鼠)回肠中 malX 基因携带细菌簇增加。
Splenda 促进了(富含拟杆菌门)自发性回肠 CD 模型中肠道变形菌、微生物组紊乱和生物化学 MPO 反应性。我们的结果表明,尽管 Splenda 可能会在 CD 倾向和健康宿主中导致平行的微生物组改变,但这并没有导致健康小鼠的 MPO 水平升高,只有 CD 倾向的小鼠。含有蔗糖素/麦芽糖糊精的食物的消耗可能仅在具有促炎倾向的个体(如 CD)中使 MPO 肠道反应性加重。