The ontogeny of human drug-metabolizing enzymes: Phase II: Conjugation enzymes and regulatory mechanisms

Mccarver, DG; Hines, RN

HERO ID

99370

Reference Type

Journal Article

Subtype

Review

Year

2002

Language

English

PMID

11805192

HERO ID 99370
Material Type Review
In Press No
Year 2002
Title The ontogeny of human drug-metabolizing enzymes: Phase II: Conjugation enzymes and regulatory mechanisms
Authors Mccarver, DG; Hines, RN
Journal Journal of Pharmacology and Experimental Therapeutics
Volume 300
Issue 2
Page Numbers 361-366
Abstract Changes in phase II drug-metabolizing enzyme expression during development, as well as the balance between phase I and phase II enzymes, can significantly alter the pharmacokinetics for a given drug or toxicant. Although our knowledge is incomplete, many of the phase II enzymes are expressed early in development. There is evidence for glutathione S-transferase A1/A2 (GSTA1/A2), GSTM, and GSTP1 in fetal liver, lung and kidney, although tissue-specific patterns and changes with time are observed. N-Acetyltransferase 1 (NAT1) activity also has been reported throughout gestation in fetal liver, adrenal glands, lung, kidney, and intestine. Only postnatal changes in NAT1 expression were apparent. Nothing is known about human NAT2 developmental expression. Some UDP-glucuronosyltransferase and sulfotransferase isoforms also are detectable in fetal liver and other tissues by the first or second trimester, and substantial changes in isoform expression patterns, as well as overall expression levels, are observed with increasing maturity. Finally, expression of both epoxide hydrolases 1 and 2 (EPHX1 and EPHX2) is observed in fetal liver, and for the former, increased expression with time has been documented. Less is known about ontogenic molecular control mechanisms. Limited data suggest that the hepatocyte nuclear factor and CCAAT/enhancer binding protein families are critical for fetal liver drug-metabolizing enzyme expression whereas D element binding protein and related factors may regulate postnatal hepatic expression. There is a paucity of data regarding mechanisms for the onset of extrahepatic fetal expression or specific mechanisms determining temporal switches, such as those observed within the CYP3A and flavin-containing monooxygenase families.
Doi 10.1124/jpet.300.2.361
Pmid 11805192
Wosid WOS:000173518900002
Url http://jpet.aspetjournals.org/lookup/doi/10.1124/jpet.300.2.361
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English
Keyword Acetyltransferases/metabolism; Aging/*metabolism; Epoxide Hydrolases/metabolism; Gene Expression Regulation, Enzymologic/*physiology; Glucuronosyltransferase/metabolism; Glutathione Transferase/metabolism; Humans; Pharmaceutical Preparations/*metabolism; Sulfotransferases/metabolism; gamma-Glutamyl Hydrolase/biosynthesis/genetics/*metabolism
Is Qa No