Procyanidins could act as antioxidant protectors of the gut epithelium

ERLEJMAN A.G.; FRAGA C.G.; OTEIZA P.I.

Santa Barbara, California, EEUU.

Congreso; Oxidants and antioxidants in biology. Annual meeting of the OXYGEN CLUB OF CALIFORNIA; 2006

OXYGEN CLUB OF CALIFORNIA

Large procyanidins are potent natural antioxidants acquired with the diet. However due to their high molecular weight they are not absorbed, and are poorly degraded by the intestinal microflora. The aim of this work was to investigate the capacity of hexameric procyanidins to interact with intestinal cells. Caco-2 cells forming an epithelial monolayer were incubated in the presence of a fraction of hexamers isolated from cocoa. Hexamers interacted with the cell plasma membrane as evidenced by the increase in the transepithelial electrical resistance of the cell monolayers. At physiologically relevant concentrations, hexamers protected cells from: a) the oxidation and loss of barrier integrity mediated by the lipophilic free radical generator (2,2’-azobis (2,4-dimethylvaleronitrile, AMVN); b) the cytotoxicity and loss of barrier integrity promoted by bile salts; and c) the TNFa- and IL-1-induced activation of NF- kB. Under the current experimental conditions, hexamers did not affect the integrity and functionality of Caco-2 monolayers. Results show that hexamers can interact with Caco-2 cell membranes and act as antioxidant, protecting cells from different extra cellular cytotoxic and pro-inflammatory stimuli. At the oral cavity and gastrointestinal tract, large procyanidins could exert beneficial health effects in pathologies such us inflammatory diseases, alterations in the intestinal barrier permeability and cancer.