Explain the metabolic pathways of Cytochromes P450 to lipid lowering agents and grapefruit and acetaminophen and grapefruit

Question

Explain metabolic pathways of Cytochrome 450 to a. lipid lowering agents and grapefruit and b. Acetaminophen and grapefruit

Identify the several effects to the human body when these enzymes are altered by food/ nutrients in relation to metabolic pathways of cytochrome 450 to lipid lowering agents and grapefruit and Acetaminophen and grapefruit.

Answer 1

The question concerns the role of the cytochrome P450 isozyme CYP34A in the metabolism and deactivation of drugs like statins. CYP34A is expressed in the tissues of the intestines and the liver. As an enzyme it has very broad substrate specificity and catalyzes the oxidation of a wide variety of natural compounds as well as synthetic drugs by converting a C-H group to C-OH.

CYP34A is irreversibly inhibited by furanocoumarins found in grapefruit juice. Inhibition of CYP34A prevents the metabolism of drugs such as statins thereby increasing their effective concentration in the body.

Acetaminophen is not metabolized by CYP34A and so it's levels are unaffected by consuming grapefruit.