Influence of dietary antioxidants on polyphenol intestinal absorption and metabolism in rats

The ingestion of complex foodstuff implicates the simultaneous presence along the digestive tract of several antioxidants micronutrients. This work aimed to determine if the interactions that may occur at the digestive level between polyphenols and other antioxidant micronutrients may modulate the fate of polyphenols in the splanchnic area. This study was conducted in a rat in situ intestinal perfusion model. Polyphenols (gallic and caffeic acids, catechin, and naringenin) were perfused with or without an antioxidant cocktail. For gallic acid, a significant reduction (-20%) of its net transfer through the brush border associated with a drastic decrease of its intestinal secretion of conjugates (-90%) was observed. By contrast, the transfer of catechin through the brush border increased (18%) and the secretion of its conjugates was twice in the presence of the antioxidants. Perfused polyphenols largely differed in their respective biliary secretion, but these fluxes were not modified by the presence of the antioxidant cocktail. Finally, the simultaneous presence in the small intestine of polyphenols and other dietary antioxidants never affects polyphenol splanchnic metabolism but may modify their intestinal transport without noticeable consequence on their final availability for peripheral tissues.