(±)11(12)-EET is a fully racemic version of the R/S enantiomeric forms biosynthesized from arachidonic acid by cytochrome P450 enzymes.[1][2][3[] A higher proportion of 11(R),12(S)-EET is produced by the CYP450 isoforms CYP2C23 and CYP2C24 while CYP2B2 produces a higher proportion of 11(S),12(R)-EET.[3] 11(12)-EET has been shown, along with 8(9)-EET to play a role in the recovery of depleted calcium pools in cultured smooth muscle cells[4] It also inhibits basolateral 18-pS potassium channels in the renal cortical collecting duct when used at a concentration of 100 nM.[5] 11(12)-EET (50 µg/kg per day) increases adhesion of isolated peripheral blood leukocytes in a chamber coated with P-selectin and ICAM-1 but does not affect choroidal neovascularization size following laser photocoagulation[6] It also has anti-inflammatory, angiogenic, and cardioprotective properties[7]
Reference:
[1]. Chacos, N., Falck, J.R., Wixtrom, C., et al. Novel epoxides formed during the liver cytochrome P-450 oxidation of arachidonic acid. Biochem. Biophys. Res. Commun. 104(3), 916-922 (1982).
[2]. Oliw, E.H., Guengerich, F.P., and Oates, J.A. Oxygenation of arachidonic acid by hepatic monooxygenases. Isolation and metabolism of four epoxide intermediates. J. Biol. Chem. 257(7), 3771-3781 (1982).
[3]. Capdevila, J.H., Falck, J.R., and Harris, R.C. Cytochrome P450 and arachidonic acid bioactivation: Molecular and functional properties of the arachidonate monooxygenase. J. Lipid Res. 41(2), 163-181 (2000).
[4]. Graber, M.N., Alfonso, A., and Gill, D.L. Recovery of Ca2+ pools and growth in Ca2+ pool-depleted cells is mediated by specific epoxyeicosatrienoic acids derived from arachidonic acid. J. Biol. Chem. 272(47), 29546-29553 (1997).
[5]. Wang, Z., Wei, Y., Falck, J.R., et al. Arachidonic acid inhibits basolateral K channels in the cortical collecting duct via cytochrome P-450 epoxygenase-dependent metabolic pathways. Am. J. Physiol. Renal Physiol. 294(6), F1441-F1447 (2008).
[6]. Hasegawa, E., Inafuku, S., Mulki, L., et al. Cytochrome P450 monooxygenase lipid metabolites are significant second messengers in the resolution of choroidal neovascularization. Proc. Natl. Acad. Sci. U.S.A. 114(36), E7545-E7553 (2017).
[7]. Spector, A.A. Arachidonic acid cytochrome P450 epoxygenase pathway. J. Lipid Res. 50(Suppl), S52-S56 (2009).