title: Transport of cranberry A-type procyanidin dimers, trimers, and tetramers across monolayers of human intestinal epithelial Caco-2 cells.
abstract: A-type procyanidin oligomers in cranberries are known to inhibit the adhesion of uropathogenic bacteria. B-type procyanidin dimers and trimers are absorbed by humans. The absorption of A-type procyanidins from cranberries in humans has not been demonstrated. This study examined the transport of A-type cranberry procyanidin dimers, trimers, and tetramers on differentiated human intestinal epithelial Caco-2 cell monolayers. Procyanidins were extracted from cranberries and purified using chromatographic methods. Fraction I contained predominantly A-type procyanidin dimer A2 [epicatechin-(2-O-7, 4-8)-epicatechin]. Fraction II contained primarily A-type trimers and tetramers, with B-type trimers, A-type pentamers, and A-type hexamers being minor components. Fraction I or II in solution was added onto the apical side of the Caco-2 cell membranes. The media at the basolateral side of the membranes were analyzed using HPLC-MS(n) after 2 h. Data indicated that procyanidin dimer A2 in fraction I and A-type trimers and tetramers in fraction II traversed across Caco-2 cell monolayers with transport ratio of 0.6%, 0.4%, and 0.2%, respectively. This study demonstrated that A-type dimers, trimers, and tetramers were transported across Caco-2 cells at low rates, suggesting that they could be absorbed by humans after cranberry consumption.
authors.affiliation: Food Science and Human Nutrition Department, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, Florida 32611, USA.
authors.forename: Keqin
authors.initials: K
authors.lastname: Ou
authors.forename: Susan S
authors.initials: SS
authors.lastname: Percival
authors.forename: Tao
authors.initials: T
authors.lastname: Zou
authors.forename: Christina
authors.initials: C
authors.lastname: Khoo
authors.forename: Liwei
authors.initials: L
authors.lastname: Gu
mesh_terms: D001682:Biological Availability; D001692:Biological Transport; D018938:Caco-2 Cells; D005638:Fruit / Q000737:chemistry*; D006801:Humans; D007408:Intestinal Absorption; D007413:Intestinal Mucosa / Q000378:metabolism*; D044945:Proanthocyanidins / Q000378:metabolism / Q000493:pharmacokinetics*; D029799:Vaccinium macrocarpon / Q000737:chemistry*
chemical_list: D044945:Proanthocyanidins