Pharmacokinetic studies of green tea catechins in maternal plasma and fetuses in rats.
We carried out a pharmacokinetic study to determine the levels and profiles of catechins in pregnant rats and their fetuses after ingestion of green tea extract (GTE). We measured total catechin levels after enzyme digestions. Dams, at 15.5 days of gestation, were fed with GTE and catechins were measured in the maternal plasma, placenta, and fetus 0, 0.5, 1, 2, 3, 5, 8, 10, 12, 16, and 20 h after maternal GTE intake. The pharmacokinetic changes were analyzed by non compartmental models. We found that maternal plasma concentrations of catechins were about 10 times higher than in placenta and 50-100 times higher than in the fetus. AUC and Cmax levels of (-)-epicatechin (EC) were the highest in plasma while the levels of (-)-epigallocatechin gallate (EGCG) were the highest in the placenta and the fetus. The exposure level of catechin derivatives was higher than the gallate derivatives in maternal plasma after normalization but reversed in the placenta and fetus. The absorption of epi-isomers in plasma was found to be more favorable than their non epi-isomer counterparts. EGCG had the highest level of exposure (AUC) and the highest Cmax in the fetus, implying it may have potential for in utero antioxidant protection.
Chu
Kai On
KO
Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, 3/F, Hong Kong Eye Hospital, 147K, Argyle Street, Kowloon, Hong Kong.
Wang
Chi Chiu
CC
Chu
Ching Yan
CY
Chan
Kwok Ping
KP
Rogers
Michael Scott
MS
Choy
Kwong Wai
KW
Pang
Chi Pui
CP
D000818:Animals; D002392:Catechin / Q000097:blood / Q000493:pharmacokinetics*; D005260:Female; D005333:Fetus / Q000378:metabolism*; D008431:Maternal-Fetal Exchange; D010920:Placenta / Q000378:metabolism; D011247:Pregnancy; D051381:Rats; D017207:Rats, Sprague-Dawley; D013662:Tea / Q000737:chemistry*; D014018:Tissue Distribution
D013662:Tea; D002392:Catechin