Cytochrome P450 1A2 (CYP1A2)

Cytochrome P-450 1A2 (CYP1A2) is a microsomal monooxygenase enzyme predominantly expressed in the human liver, accounting for approximately 13% of total hepatic cytochrome P450 content. It plays a key role in the metabolism of a wide variety of substances, including clinically important drugs (over 110 have been described), procarcinogens (e.g., aromatic amines, benzo[a]pyrene), and several endogenous compounds such as steroids. CYP1A2 acts by catalyzing the oxidation of substrates, which usually increases their water solubility for biliary or renal excretion. Its activity is highly variable among individuals owing to genetic polymorphisms, regulation by environmental factors (especially smoking), and reversible or irreversible inhibition by other drugs and dietary substances. Structural characterization reveals a compact, closed active site cavity adapted for large planar substrates. CYP1A2 levels and activity are induced via the aromatic hydrocarbon receptor pathway, and altered enzyme expression or activity can greatly impact drug efficacy, toxicity, and susceptibility to diseases, particularly cancer, by activating procarcinogens.

Other names

CYP1A2P450 1A2Cytochrome P-450 1A2Cytochrome P450 family 1 subfamily A member 2CYPA1A2

Substrate oxidation via monooxygenase activity (increases solubility of drugs for clearance); Inhibition (decreases metabolic clearance of other drugs, increases risk of toxicity); Induction (increases metabolic clearance, may reduce efficacy of drugs metabolized by CYP1A2)