Comprehensive analysis of the mouse cytochrome P450 family responsible for omega-3 epoxidation of eicosapentaenoic acid

Abstract

Metabolites generated via oxygenation of the omega-3 double bond (omega-3 oxygenation) in eicosapentaenoic acid (EPA) have recently been identified as novel anti-inflammatory lipid mediators. Therefore, oxygenase(s) responsible for this metabolic pathway are of particular interest. We performed genome-wide screening of mouse cytochrome P450 (CYP) isoforms to explore enzymes involved in omega-3 oxygenation of EPA. As a result, 5 CYP isoforms (mouse Cyp1a2, 2c50, 4a12a, 4a12b, and 4f18) were selected and identified to confer omega-3 epoxidation of EPA to yield 17,18-epoxyeicosatetraenoic acid (17,18-EpETE). Stereoselective production of 17,18-EpETE by each CYP isoform was confirmed, and molecular modeling indicated that chiral differences stem from different EPA binding conformations in the catalytic domains of respective CYP enzymes.

Dietary Omega-3 Fatty Acid Dampens Allergic Rhinitis via Eosinophilic Production of the Anti-Allergic Lipid Mediator 15-Hydroxyeicosapentaenoic Acid in Mice

“…Lipid extraction was performed as previously reported [29]. Cells were suspended in PBS and transferred to a polypropylene tube.…”

“…Lipid metabolites were analyzed by using a UPLC system (ACQUITY) (Waters, Milford, MA, USA) coupled with mass spectrometry (Orbitrap ELITE) (Thermo Fisher Scientific), with modifications of the previously reported protocol [29]. UPLC application was performed with a 1.7 mm, 1.0 × 150 mm ACQUITY UPLC BEH C18 column (Waters).…”

17( S ),18( R )‐epoxyeicosatetraenoic acid generated by cytochrome P450 BM‐3 from Bacillus megaterium inhibits the development of contact hypersensitivity via G‐protein‐coupled receptor 40‐mediated neutrophil suppression

“…In this issue, we first chemically synthesized a large amount of (±)17,18‐EpETE from EPA and found that, like commercially available Cayman (±)17,18‐EpETE, synthesized (±)17,18‐EpETE showed 2 peaks using HPLC system with chiral column. The bacterial enzyme BM‐3 has been reported to stereoselectively convert EPA into 17( S ),18( R )‐EpETE . We found that BM‐3‐derived 17( S ),18( R )‐EpETE was identical with the second peak of (±)17,18‐EpETE (Figure ).…”

“…Furthermore, CYPs also are present in the liver, lung, kidney, brain, and skin, suggesting that dietary ω3 PUFAs lead to the production of 17,18‐EpETE in various sites in the body . However, despite the many types of CYPs that exist, it is reported that only five types of CYPs can convert EPA into 17,18‐EpETE in mice, and only nine types have this function in humans . Depending on the CYP type, 17,18‐EpETE is produced in a stereoselective or non‐stereoselective manner.…”

“…Depending on the CYP type, 17,18‐EpETE is produced in a stereoselective or non‐stereoselective manner. For example, Cyp1a2 in mice and CYP2E1 in humans selectively generate 17( R ),18( S )‐EpETE, whereas Cyp4f18 in mice and CYP2D6 in humans—like BM‐3—selectively generate 17( S ),18( R )‐EpETE . In contrast, other CYPs, such as Cyp4a12a, Cyp4a12b, and Cyp2c50 in mice and CYP1A1, CYP2C19, CYP2C9, CYP2J2, CYP3A4, CYP2C18, and CYP2C8 in humans, produce both 17( R ),18( S )‐EpETE and 17( S ),18( R )‐EpETE …”