title: Oxidation of endogenous N-arachidonoylserotonin by human cytochrome P450 2U1.
abstract: Cytochrome P450 (P450) 2U1 has been shown to be expressed, at the mRNA level, in human thymus, brain, and several other tissues. Recombinant P450 2U1 was purified and used as a reagent in a metabolomic search for substrates in bovine brain. In addition to fatty acid oxidation reactions, an oxidation of endogenous N-arachidonoylserotonin was characterized. Subsequent NMR and mass spectrometry and chemical synthesis showed that the main product was the result of C-2 oxidation of the indole ring, in contrast to other human P450s that generated different products. N-Arachidonoylserotonin, first synthesized chemically and described as an inhibitor of fatty acid amide hydrolase, had previously been found in porcine and mouse intestine; we demonstrated its presence in bovine and human brain samples. The product (2-oxo) was 4-fold less active than N-arachidonoylserotonin in inhibiting fatty acid amide hydrolase. The rate of oxidation of N-arachidonoylserotonin was similar to that of arachidonic acid, one of the previously identified fatty acid substrates of P450 2U1. The demonstration of the oxidation of N-arachidonoylserotonin by P450 2U1 suggests a possible role in human brain and possibly other sites.
authors.affiliation: Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146; Pharmacology and Toxicology Division, Institute of Molecular and Translational Medicine, Palacky University Olomouc, 775 15 Olomouc, Czech Republic.
authors.forename: Michal
authors.initials: M
authors.lastname: Siller
authors.affiliation: Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146.
authors.forename: Sandeep
authors.initials: S
authors.lastname: Goyal
authors.affiliation: Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146.
authors.forename: Francis K
authors.initials: FK
authors.lastname: Yoshimoto
authors.affiliation: Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146.
authors.forename: Yi
authors.initials: Y
authors.lastname: Xiao
authors.affiliation: Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146.
authors.forename: Shouzou
authors.initials: S
authors.lastname: Wei
authors.affiliation: Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146. Electronic address: f.guengerich@vanderbilt.edu.
authors.forename: F Peter
authors.initials: FP
authors.lastname: Guengerich
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001095:Arachidonic Acids / Q000378:metabolism*; D001921:Brain / Q000378:metabolism; D002384:Catalysis; D002417:Cattle; D002853:Chromatography, Liquid; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D000072467:Cytochrome P450 Family 2; D004912:Erythrocytes / Q000201:enzymology; D004926:Escherichia coli / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D007211:Indoles / Q000378:metabolism; D008099:Liver / Q000201:enzymology; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D010100:Oxygen / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D011485:Protein Binding; D040901:Proteomics; D017386:Sequence Homology, Amino Acid; D012701:Serotonin / Q000031:analogs & derivatives* / Q000378:metabolism
chemical_list: D001095:Arachidonic Acids; D007211:Indoles; C114007:arachidonoylserotonin; D012701:Serotonin; D003577:Cytochrome P-450 Enzyme System; C484320:CYP2U1 protein, human; D000072467:Cytochrome P450 Family 2; D010100:Oxygen
keywords: Arachidonic Acid; Cytochrome P450; Eicosanoid; Lipid Oxidation; Mass Spectrometry (MS)