title: Trefoil factor 3 (TFF3) from human breast milk activates PAR-2 receptors, of the intestinal epithelial cells HT-29, regulating cytokines and defensins.
abstract: Trefoil factors are effector molecules in gastrointestinal tract physiology. Each one improves healing of the gastrointestinal tract. Trefoil factors may be grouped into three classes: the gastric peptides (TFF1), spasmolytic peptide (TFF2) and intestinal trefoil factor (TFF3). Significant amounts of TFF3 are present in human breast milk. Previously, we have reported that trefoil factor 3 isolated from human breast milk produces down regulation of cytokines and promotes human beta defensins expression in intestinal epithelial cells. This study aimed to determine the molecular mechanism involved. Here we showed that the presence of TFF3 strongly correlated with protease activated receptors 2 (PAR-2) activation in human intestinal cells. Intracellular calcium ((Ca2+)i)mobilization was induced by the treatment with: 1) TFF3, 2) synthetic PAR-2 agonist peptide. The co-treatment with a synthetic PAR-2 antagonist peptide and TFF3 eliminates the latter's effect. Additionally, we demonstrated the existence of interactions among TFF3 and PAR-2 receptors through far Western blot and co-precipitation. Finally, down regulation of PAR-2 by siRNA resulted in a decrease of TFF3 induced intracellular (Ca2+)i mobilization, cytokine regulation and defensins expression. These findings suggest that TFF3 activates intestinal cells through PAR-2 (Fig. 4, Ref. 19).
authors.forename: G J
authors.initials: GJ
authors.lastname: Barrera
authors.forename: G Sanchez
authors.initials: GS
authors.lastname: Tortolero
mesh_terms: D015153:Blotting, Western; D002118:Calcium / Q000378:metabolism; D016207:Cytokines / Q000187:drug effects* / Q000378:metabolism; D023082:Defensins / Q000187:drug effects* / Q000378:metabolism; D015536:Down-Regulation / Q000187:drug effects; D004591:Electrophoresis, Polyacrylamide Gel; D004847:Epithelial Cells / Q000187:drug effects* / Q000378:metabolism; D005260:Female; D019073:HT29 Cells; D006801:Humans; D007413:Intestinal Mucosa / Q000166:cytology; D008895:Milk, Human / Q000737:chemistry*; D009842:Oligopeptides / Q000494:pharmacology; D044464:Receptor, PAR-2 / Q000187:drug effects* / Q000378:metabolism; D015398:Signal Transduction; D000071165:Trefoil Factor-3 / Q000494:pharmacology*
chemical_list: D016207:Cytokines; D023082:Defensins; D009842:Oligopeptides; D044464:Receptor, PAR-2; C082495:TFF3 protein, human; D000071165:Trefoil Factor-3; C112356:seryl-leucyl-isoleucyl-glycyl--arginyl-leucinamide; D002118:Calcium
keywords: breast milk; cytokines.; defensins; protease-activated receptor 2 PAR-2; trefoil factor family TFF