A1 Refereed original research article in a scientific journal

In vitro glucuronidation of 7-hydroxycoumarin derivatives in intestine and liver microsomes of Beagle dogs




AuthorsRisto O. Juvonen, Aki T. Heikkinen, Olli Kärkkäinen, Rabia Jehangir, Juhani Huuskonen, Johanna Troberg, Hannu Raunio, Olli T. Pentikäinen, Moshe Finel

PublisherELSEVIER

Publication year2020

JournalEuropean Journal of Pharmaceutical Sciences

Journal name in sourceEUROPEAN JOURNAL OF PHARMACEUTICAL SCIENCES

Journal acronymEUR J PHARM SCI

Article numberARTN 105118

Volume141

Number of pages9

ISSN0928-0987

eISSN1879-0720

DOIhttps://doi.org/10.1016/j.ejps.2019.105118

Self-archived copy’s web addresshttps://jyx.jyu.fi/handle/123456789/66174


Abstract
Beagle dog is a standard animal model for evaluating nonclinical pharmacokinetics of new drug candidates. Glucuronidation in intestine and liver is an important first-pass drug metabolic pathway, especially for phenolic compounds. This study evaluated the glucuronidation characteristics of several 7-hydroxycoumarin derivatives in beagle dog's intestine and liver in vitro. To this end, glucuronidation rates of 7-hydroxycoumarin (compound 1), 7-hydroxy-4-trifluoromethylcoumarin (2), 6-methoxy-7-hydroxycoumarin (3), 7-hydroxy-3-(4-tolyl)coumarin (4), 3-(4-fluorophenyl)coumarin (5), 7-hydroxy-3-(4-hydroxyphenyl)coumarin (6), 7-hydroxy-3-(4-methoxyphenyl)coumarin (7), and 7-hydroxy-3-(1H-1,2,4-tirazole)coumarin (8) were determined in dog's intestine and liver microsomes, as well as recombinant dog UGT1A enzymes. The glucuronidation rates of 1, 2 and 3 were 3-10 times higher in liver than in small intestine microsomes, whereas glucuronidation rates of 5, 6, 7 and 8 were similar in microsomes from both tissues. In the colon, glucuronidation of 1 and 2 was 3-5 times faster than in small intestine. dUGT1A11 glucuronidated efficiently all the substrates and was more efficient catalyst for 8 than any other dUGT1A. Other active enzymes were dUGT1A2 that glucuronidated efficiently 2, 3, 4, 5, 6 and 7, while dUGT1A10 glucuronidated efficiently 1, 2, 3, 4, 5 and 7. Kinetic analyses revealed that the compounds' Km values varied between 1.1 (dUGT1A10 and 2) and 250 mu M (dUGT1A7 and 4). The results further strengthen the concept that dog intestine has high capacity for glucuronidation, and that different dUGT1As mediate glucuronidation with distinct substrates selectivity in dog and human.



Last updated on 2024-26-11 at 16:17