title: [Changes of tight junction claudin-1,-3,-4 protein expression in the intestinal mucosa in patients with irritable bowel syndrome].
abstract: OBJECTIVE
  To investigate the changes of intestinal mucosal tight junction proteins claudin-1, -3, -4 in patients with irritable bowel syndrome (IBS), and elucidate its possible role in the bowel evacuation habit changes and formation in these patients.
  
  
  METHODS
  Western blotting was employed to determine tight junction protein claudin-1,-3,-4 levels in the intestinal mucosa of patients in the control group, diarrhea-predominant IBS (D-IBS) group and constipation-predominant IBS (C-IBS) group.
  
  
  RESULTS
  Compared with the control group, D-IBS patients showed significantly decreased claudin-1 protein levels in both the small intestinal and colonic mucosae (P<0.05), whereas C-IBS patients had significantly elevated claudin-1 protein levels (P<0.05). No significant difference was found in claudin-3 protein expression in the both small intestinal and colonic mucosae between the D-IBS group and the control group (P>0.05), but claudin-3 protein level was shown to increase significantly in C-IBS patients (P<0.05). Claudin-4 protein followed the same pattern of alteration as claudin-1.
  
  
  CONCLUSIONS
  Down-regulated claudin-1 and -4 expressions can be associated with bowel evacuation habit changes and formation in patients with D-IBS, but up-regulated claudin-1, -3 and -4 expressions may relate to such bowel changes in patients with C-IBS.
authors: Department of Gastroenterology, Second Hospital of Xi'an Jiaotong University, Xi'an 710004, China. kwmys@126.com
authors: Wu-ming
authors: WM
authors: Kong
authors: Jun
authors: J
authors: Gong
authors: Lei
authors: L
authors: Dong
authors: Jun-rong
authors: JR
authors: Xu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D015153:Blotting, Western; D016022:Case-Control Studies; D062445:Claudin-1; D062465:Claudin-3; D062506:Claudin-4; D003106:Colon / Q000378:metabolism / Q000473:pathology; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism* / Q000473:pathology*; D043183:Irritable Bowel Syndrome / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D008875:Middle Aged; D019108:Tight Junctions / Q000378:metabolism*; D055815:Young Adult
chemical_list: C568108:CLDN1 protein, human; C568122:CLDN3 protein, human; C568157:CLDN4 protein, human; D062445:Claudin-1; D062465:Claudin-3; D062506:Claudin-4; D008565:Membrane Proteins