title: Inhibition of folic acid uptake by catechins and tea extracts in Caco-2 cells.
abstract: In this present study it was aimed to determine whether the catechins contained in green tea and the whole extracts of Camellia sinensis (Theaceae) inhibit the uptake of folic acid by Caco-2 cell monolayers. Our results indicate that (-)-epigallocatechin 3-gallate (EGCG) and (-)-epicatechin 3-gallate (ECG) inhibit cellular folic acid uptake with IC50 values of 34.8 micromol/L and 30.8 micromol/L, respectively. Furthermore, green and black tea extracts were also found to inhibit folic acid uptake with IC50 values of approximately 7.5 and 3.6 mg/mL, respectively. According to these results, simultaneous intake of tea and folic acid may inhibit intestinal folic acid absorption. The consequences with respect to the folate status of the body will need to be examined in vivo.
authors.affiliation: Institute of Pharmacy, Johannes Gutenberg-University, Mainz, Germany.
authors.forename: N Ceren
authors.initials: NC
authors.lastname: Alemdaroglu
authors.forename: Siegfried
authors.initials: S
authors.lastname: Wolffram
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Boissel
authors.forename: Ellen
authors.initials: E
authors.lastname: Closs
authors.forename: Hildegard
authors.initials: H
authors.lastname: Spahn-Langguth
authors.forename: Peter
authors.initials: P
authors.lastname: Langguth
mesh_terms: D000975:Antioxidants / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D018938:Caco-2 Cells / Q000187:drug effects / Q000378:metabolism; D028241:Camellia sinensis; D002392:Catechin / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D005492:Folic Acid / Q000378:metabolism*; D006801:Humans; D020128:Inhibitory Concentration 50; D007408:Intestinal Absorption / Q000187:drug effects*; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use
chemical_list: D000975:Antioxidants; D010936:Plant Extracts; D002392:Catechin; D005492:Folic Acid