Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.1.6.1 (
sulfatase
)
3,205
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Efavirenz
(
EFV
) is principally metabolized by CYP2B6 to 8-hydroxy-efavirenz (8OH-
EFV
) and to a lesser extent by CYP2A6 to 7-hydroxy-efavirenz (7OH-
EFV
). So far, most metabolite profile analyses have been restricted to 8OH-
EFV
, 7OH-
EFV
, and
EFV
-N-glucuronide, even though these metabolites represent a minor percentage of
EFV
metabolites present in vivo. We have performed a quantitative phase I and II metabolite profile analysis by tandem mass spectrometry of plasma, cerebrospinal fluid (CSF), and urine samples in 71 human immunodeficiency virus patients taking efavirenz, prior to and after enzymatic (glucuronidase and
sulfatase
) hydrolysis. We have shown that phase II metabolites constitute the major part of the known circulating efavirenz species in humans. The 8OH-
EFV
-glucuronide (gln) and 8OH-
EFV
-sulfate (identified for the first time) in humans were found to be 64- and 7-fold higher than the parent 8OH-
EFV
, respectively. In individuals (n = 67) genotyped for CYP2B6, 2A6, and CYP3A metabolic pathways, 8OH-
EFV
/
EFV
ratios in plasma were an index of CYP2B6 phenotypic activity (P < 0.0001), which was also reflected by phase II metabolites 8OH-
EFV
-glucuronide/
EFV
and 8OH-
EFV
-sulfate/
EFV
ratios. Neither
EFV
nor 8OH-
EFV
, nor any other considered metabolites in plasma were associated with an increased risk of central nervous system (CNS) toxicity. In CSF, 8OH-
EFV
levels were not influenced by CYP2B6 genotypes and did not predict CNS toxicity. The phase II metabolites 8OH-
EFV
-gln, 8OH-
EFV
-sulfate, and 7OH-
EFV
-gln were present in CSF at 2- to 9-fold higher concentrations than 8OH-
EFV
. The potential contribution of known and previously unreported
EFV
metabolites in CSF to the neuropsychological effects of efavirenz needs to be further examined in larger cohort studies.
...
PMID:In Vivo Profiling and Distribution of Known and Novel Phase I and Phase II Metabolites of Efavirenz in Plasma, Urine, and Cerebrospinal Fluid. 2655 12