title: A marketed fermented dairy product containing Bifidobacterium lactis CNCM I-2494 suppresses gut hypersensitivity and colonic barrier disruption induced by acute stress in rats.
abstract: BACKGROUND
  Fermented milk (FM) containing Bifidobacterium lactis CNCM I-2494 and yogurt strains improves irritable bowel syndrome (IBS) symptoms in constipated IBS patients. In rats, stressful events exacerbate IBS symptoms and result in the alteration of gut sensitivity and permeability via epithelial cell cytoskeleton contraction. In a stress model, we aimed at evaluating the effect of B. lactis CNCM I-2494 as a pure strain or contained in an FM product on visceral sensitivity and the impact of this FM on intestinal barrier integrity.
  
  
  METHODS
  Visceral sensitivity was analyzed in rats subjected to partial restraint stress (PRS). Rats received during 15 days the B. lactis as a pure strain (10(6) to 10(10) CFU mL(-1)), B. lactis in an FM product (10(8) CFU g(-1), diluted or not), or a control product. Gut paracellular permeability, colonic occluding and Jam-A proteins, and blood endotoxin levels were determined in rats receiving B. lactis in an FM product submitted or not to a PRS.
  
  
  RESULTS
  The FM product showed a dose-dependent inhibitory effect on stress-induced visceral hypersensitivity. A similar antihyperalgesic effect was observed at 10(10) CFU mL(-1) of pure B. lactis administration. The FM product prevented the increase in intestinal permeability induced by PRS and restored occludin and JAM-A expressions to control levels. The FM product abolished the increase concentration of blood endotoxin induced by PRS.
  
  
  CONCLUSIONS
  This study illustrates that a probiotic food containing B. lactis CNCM I-2494 strain reduces visceral hypersensitivity associated with acute stress by normalizing intestinal epithelial barrier via a synergistic interplay with the different probiotic strains and/or metabolites contained in this product.
authors.affiliation: Neuro-Gastroenterology & Nutrition Unit, Toxalim, UMR 1331, Toulouse, France.
authors.forename: S
authors.initials: S
authors.lastname: Agostini
authors.forename: M
authors.initials: M
authors.lastname: Goubern
authors.forename: V
authors.initials: V
authors.lastname: Tondereau
authors.forename: C
authors.initials: C
authors.lastname: Salvador-Cartier
authors.forename: V
authors.initials: V
authors.lastname: Bezirard
authors.forename: M
authors.initials: M
authors.lastname: Lévèque
authors.forename: H
authors.initials: H
authors.lastname: Keränen
authors.forename: V
authors.initials: V
authors.lastname: Theodorou
authors.forename: S
authors.initials: S
authors.lastname: Bourdu-Naturel
authors.forename: N
authors.initials: N
authors.lastname: Goupil-Feuillerat
authors.forename: S
authors.initials: S
authors.lastname: Legrain-Raspaud
authors.forename: H
authors.initials: H
authors.lastname: Eutamene
mesh_terms: D000818:Animals; D001644:Bifidobacterium; D003106:Colon / Q000382:microbiology* / Q000503:physiopathology; D043302:Cultured Milk Products; D004195:Disease Models, Animal; D005260:Female; D006941:Hyperesthesia / Q000209:etiology / Q000382:microbiology* / Q000503:physiopathology; D007103:Immobilization; D007413:Intestinal Mucosa / Q000382:microbiology / Q000503:physiopathology; D043183:Irritable Bowel Syndrome / Q000382:microbiology / Q000503:physiopathology / Q000628:therapy*; D017288:Pain Threshold / Q000502:physiology; D019936:Probiotics / Q000627:therapeutic use*; D051381:Rats; D017208:Rats, Wistar; D013315:Stress, Psychological / Q000150:complications