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Drug Metabolizing Enzymes

  • Siamak Cyrus Khojasteh
  • Harvey Wong
  • Cornelis E. C. A. Hop
Chapter

Abstract

Metabolism is the major elimination pathway of a drug from the body. Drug metabolizing enzymes (DMEs) are mainly present in the liver, intestine, and blood and are responsible for converting lipophilic drugs to more hydrophilic compounds to facilitate their excretion from the body. DMEs are classified as either Phase I or Phase II enzymes. Phase I DMEs are responsible for oxidation, reduction, and hydrolysis, and Phase II DME are responsible for conjugation (not necessarily sequential). Here we discuss the DMEs involved in Phase I and Phase II reactions, their subcellular locations, cofactors, organ distributions, mechanisms of reactions, and typical substrates and inhibitors.

Keywords

Subcellular Location Flavin Adenine Dinucleotide Flavin Adenine Dinucleotide Ethacrynic Acid Styrene Oxide 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Abbreviations

ABT

Aminobenzotriazole

ADH

Alcohol dehydrogenase

AKR

Aldo-keto reductase

ALDH

Aldehyde dehydrogenase

AO

Aldehyde oxidase

AZT

3′-Azido-3′-deoxythimidine

BSO

l-Buthionine-sulfoximine

CDNB

1-Chloro-2,4-dinitrobenzene

CL

Clearance

DCNP

2,6-Dichloro-4-nitrophenol

DME

Drug metabolizing enzyme

EC

Enzyme classification number based on enzyme function

EH

Epoxide hydrolase

ER

Endoplasmic reticulum (i.e., microsomes)

FAD

Flavin adenine dinucleotide

FMO

Flavin-containing monooxygenase

GI

Gastrointestinal

GST

Glutathione S-transferase

LM

Liver microsomes

MAO

Monoamine oxidase

mCPBA

m-Chloroperoxybenzoic acid

NAC

N-Acetylcysteine

NAD

Nicotinamide adenine dinucleotide

NADPH

Nicotinamide adenine dinucleotide phosphate

NAT

N-Acetyltransferase

P450

Cytochrome P450

PAPS

3′-Phosphoadenosine-5′-phosphosulfate

PM

Poor metabolizer

NQO

NADPH:quinone reductase

SAM

S-Adenosyl methionine

SULT

Sulfotransferase

UDPGA

Uridine diphosphoglucuronic acid

UGT

Uridine diphosphate glucuronosyltransferase

XDH

Xanthine dehydrogenase

XO

Xanthine oxidase

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Additional Reading

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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Siamak Cyrus Khojasteh
    • 1
  • Harvey Wong
    • 1
  • Cornelis E. C. A. Hop
    • 1
  1. 1.Genentech, Inc.San FranciscoUSA

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