Understanding the detailed ontogeny of xenobiotic metabolizing enzymes is important if
we are to be able to predict the risk of toxicity to the developing fetus or the fate of drugs in neonates
and children. This review summarizes current knowledge of the development of the major families of
conjugating enzymes in humans: the UDP-glucuronosyltransferases, sulfotransferases, glutathione
S-transferases, arylamine N-acetyltransferases and methyltransferases; little is known of the last three.
Based on the available information, sulfation appears to be the most highly developed pathway during
fetal development where glucuronidation in particular is lacking. Following birth, glucuronidation
capacity develops rapidly and for many of the enzymes adult capacity occurs in mid-late childhood. The importance of
developing pharmacokinetic and physiology-based pharmacokinetic models to support the more informed use of drugs in
children is highlighted.
Keywords: Conjugation, development, glucuronidation, sulfation, xenobiotic metabolism.
Rights & PermissionsPrintExport