Cytochrome P
4502C8 (CYP2C8) is a member of the
cytochrome P450
Cytochromes P450 (P450s or CYPs) are a Protein superfamily, superfamily of enzymes containing heme as a cofactor (biochemistry), cofactor that mostly, but not exclusively, function as monooxygenases. However, they are not omnipresent; for examp ...
mixed-function oxidase system involved in the metabolism of
xenobiotics in the body. Cytochrome P
4502C8 also possesses
epoxygenase
Epoxygenases are a set of membrane-bound, heme-containing cytochrome P450 (CYP450 or just CYP) enzymes that metabolize polyunsaturated fatty acids (PUFAs) to epoxide products that have a range of biological activities.
The most thoroughly-studi ...
activity, i.e. it metabolizes long-chain
polyunsaturated fatty acids
In biochemistry and nutrition, a polyunsaturated fat is a fat that contains a polyunsaturated fatty acid (abbreviated PUFA), which is a subclass of fatty acid characterized by a backbone with two or more carbon–carbon double bonds.
Some polyunsa ...
, e.g.
arachidonic acid
Arachidonic acid (AA, sometimes ARA) is a polyunsaturated omega−6 fatty acid 20:4(ω−6), or 20:4(5,8,11,14). It is a precursor in the formation of leukotrienes, prostaglandins, and thromboxanes.
Together with omega−3 fatty acids an ...
,
eicosapentaenoic acid,
docosahexaenoic acid
Docosahexaenoic acid (DHA) is an omega−3 fatty acid that is an important component of the human brain, cerebral cortex, skin, and retina. It is given the fatty acid notation 22:6(''n''−3). It can be synthesized from alpha-linolenic acid or ...
, and
linoleic acid
Linoleic acid (LA) is an organic compound with the formula . Both alkene groups () are ''cis''. It is a fatty acid sometimes denoted 18:2 (n−6) or 18:2 ''cis''-9,12. A linoleate is a salt or ester of this acid.
Linoleic acid is a polyunsat ...
to their biologically active
epoxide
In organic chemistry, an epoxide is a cyclic ether, where the ether forms a three-atom ring: two atoms of carbon and one atom of oxygen. This triangular structure has substantial ring strain, making epoxides highly reactive, more so than other ...
s.
Ligands
Following is a table of selected
substrates,
inducers and
inhibitors of 2C8.
Inhibitors of CYP2C8 can be classified by their
potency, such as:
* Strong inhibitor being one that causes at least a five-fold increase in the plasma
AUC values, or more than 80% decrease in
clearance.
[
* Moderate inhibitor being one that causes at least a two-fold increase in the plasma AUC values, or 50-80% decrease in clearance.][
* Weak inhibitor being one that causes at least a 1.25-fold but less than two-fold increase in the plasma AUC values, or 20-50% decrease in clearance.][ Retrieved on July 2011]
Where classes of agents are listed, there may be exceptions within the class.
Epoxygenase activity
CYP2C8 also possesses epoxygenase
Epoxygenases are a set of membrane-bound, heme-containing cytochrome P450 (CYP450 or just CYP) enzymes that metabolize polyunsaturated fatty acids (PUFAs) to epoxide products that have a range of biological activities.
The most thoroughly-studi ...
activity: it is one of the principal enzymes responsible for attacking various long-chain polyunsaturated fatty acids at their double (i.e. alkene
In organic chemistry, an alkene, or olefin, is a hydrocarbon containing a carbon–carbon double bond. The double bond may be internal or at the terminal position. Terminal alkenes are also known as Alpha-olefin, α-olefins.
The Internationa ...
) bonds to form epoxide
In organic chemistry, an epoxide is a cyclic ether, where the ether forms a three-atom ring: two atoms of carbon and one atom of oxygen. This triangular structure has substantial ring strain, making epoxides highly reactive, more so than other ...
products that act as signaling agents. It metabolizes: 1) arachidonic acid
Arachidonic acid (AA, sometimes ARA) is a polyunsaturated omega−6 fatty acid 20:4(ω−6), or 20:4(5,8,11,14). It is a precursor in the formation of leukotrienes, prostaglandins, and thromboxanes.
Together with omega−3 fatty acids an ...
to various epoxyeicosatrienoic acids (also termed EETs); 2) linoleic acid
Linoleic acid (LA) is an organic compound with the formula . Both alkene groups () are ''cis''. It is a fatty acid sometimes denoted 18:2 (n−6) or 18:2 ''cis''-9,12. A linoleate is a salt or ester of this acid.
Linoleic acid is a polyunsat ...
to 9,10-epoxy octadecenoic acids (also termed vernolic acid
Vernolic acid (leukotoxin B or isoleukotoxin) is a long chain fatty acid that is monounsaturated and contains an epoxide. It is a ''cis'' epoxide derived from the C12–C13 alkene of linoleic acid. Vernolic acid was first definitively character ...
, linoleic acid 9:10-oxide, or leukotoxin) and 12,13-epoxy-octadecenoic (also termed coronaric acid, linoleic acid 12,13-oxide, or isoleukotoxin); 3) docosahexaenoic acid
Docosahexaenoic acid (DHA) is an omega−3 fatty acid that is an important component of the human brain, cerebral cortex, skin, and retina. It is given the fatty acid notation 22:6(''n''−3). It can be synthesized from alpha-linolenic acid or ...
to various epoxydocosapentaenoic acids (also termed EDPs); and 4) eicosapentaenoic acid to various epoxyeicosatetraenoic acids (also termed EEQs).
Along with CYP2C8, CYP2C9
Cytochrome P450 family 2 subfamily C member 9 (abbreviated CYP2C9) is an enzyme protein. The enzyme is involved in the metabolism, by oxidation, of both xenobiotics, including drugs, and endogenous compounds, including fatty acids. In humans, t ...
, CYP2C19, CYP2J2, and possibly CYP2S1 are the main producers of EETs and, very likely, EEQs, EDPs, and the epoxides of linoleic acid.
See also
* Cytochrome P450 oxidase
Cytochromes P450 (P450s or CYPs) are a superfamily of enzymes containing heme as a cofactor that mostly, but not exclusively, function as monooxygenases. However, they are not omnipresent; for example, they have not been found in ''Escherich ...
* Epoxygenase
Epoxygenases are a set of membrane-bound, heme-containing cytochrome P450 (CYP450 or just CYP) enzymes that metabolize polyunsaturated fatty acids (PUFAs) to epoxide products that have a range of biological activities.
The most thoroughly-studi ...
References
External links
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