title: Duodenojejunal Bypass Leads to Altered Gut Microbiota and Strengthened Epithelial Barriers in Rats.
abstract: Gastrointestinal bypass changes the gut microbiota and decreases systemic endotoxemia in obese subjects. Epithelial barrier integrity is crucial for confining enteric bacteria in the lumen and preventing gut-derived endotoxemia. The effect of bypass surgery on intestinal barrier functions remains poorly understood. This study aimed to evaluate the changes in intestinal permeability and gut barrier between rats receiving Roux-en-Y duodenojejunal bypass (DJB) or sham operation (SO).
  
  
  
  Eighteen Sprague-Dawley rats were assigned to DJB or SO groups. Tissues of the alimentary, biliopancreatic, and common limbs in the small intestine, and the colon, were collected 2 weeks after operation. Mucosa-associated bacteria were quantified by colony forming units. Intestinal permeability was determined by mucosal-to-serosal dextran flux measured in Ussing chambers. Expression of occludin and proliferating cell nuclear antigen (PCNA) in the intestinal mucosa was examined by western blots.
  
  
  
  Enteric bacterial numbers were increased in the alimentary and common limbs after DJB. Reduced dextran permeability was found in the alimentary limb, common limb, and colon after DJB. Moreover, increased villus height and crypt depth were found to be associated with higher mucosal levels of occludin and PCNA levels in the alimentary and common limbs after DJB.
  
  
  
  DJB in rats altered gut microbiota and reduced intestinal permeability due to increased epithelial proliferation and tight junctional protein expression. Our results show that bypass surgery led to fortification of the intestinal barrier functions, which may provide an explanation for the decreased risk of systemic endotoxemia in postoperative patients.
authors.affiliation: Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan.|Department of Surgery, National Taiwan University Hospital Jin-Shan Branch, New Taipei City, Taiwan.|Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan.|Center for Obesity, Life Style and Metabolic Surgery, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Po-Jen
authors.initials: PJ
authors.lastname: Yang
authors.affiliation: Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan.|Center for Obesity, Life Style and Metabolic Surgery, National Taiwan University Hospital, Taipei, Taiwan.|Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Wei-Shiung
authors.initials: WS
authors.lastname: Yang
authors.affiliation: Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan.|Department of Family Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Hsiao-Ching
authors.initials: HC
authors.lastname: Nien
authors.affiliation: Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan.|Center for Obesity, Life Style and Metabolic Surgery, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Chiung-Nien
authors.initials: CN
authors.lastname: Chen
authors.affiliation: Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Po-Huang
authors.initials: PH
authors.lastname: Lee
authors.affiliation: Graduate Institute of Physiology, College of Medicine, National Taiwan University, Taipei, Taiwan. lchyu@ntu.edu.tw.
authors.forename: Linda Chia-Hui
authors.initials: LC
authors.lastname: Yu
authors.affiliation: Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan. linmt@ntu.edu.tw.
authors.forename: Ming-Tsan
authors.initials: MT
authors.lastname: Lin
mesh_terms: D000714:Anastomosis, Surgical; D000818:Animals; D050110:Bariatric Surgery; D004195:Disease Models, Animal; D004386:Duodenum / Q000601:surgery*; D004755:Enterobacteriaceae; D000069196:Gastrointestinal Microbiome / Q000502:physiology*; D007413:Intestinal Mucosa / Q000378:metabolism / Q000503:physiopathology*; D007583:Jejunum / Q000601:surgery*; D008297:Male; D009765:Obesity / Q000503:physiopathology* / Q000601:surgery*; D051381:Rats; D017207:Rats, Sprague-Dawley
keywords: Duodenojejunal bypass; Gut microbiota; Intestinal barrier; Intestinal permeability; Systemic endotoxemia