title: 1 -O-alkyl-2-(omega-oxo)acyl-sn-glycerols from shark oil and human milk fat are potential precursors of PAF mimics and GHB.
abstract: This study examines the feasibility that peroxidation and lipolysis of 1-O-alkyl-2,3-diacyl-sn-glycerols (DAGE) found in shark liver oil and human milk fat constitutes a potential source of dietary precursors of platelet activating factor (PAF) mimics and of gamma-hydroxybutyrate (GHB). Purified DAGE were converted into 1-O-alkyl-2-acyl-sn-glycerols by pancreatic lipase, without isomerization, and transformed into 1-O-alkyl-2-oxoacyl-sn-glycerols by mild autooxidation. The various core aldehydes without derivatization, as well as the corresponding dinitrophenylhydrazones, were characterized by chromatographic retention time and diagnostic ions by online electrospray mass spectrometry. Core aldehydes of oxidized shark liver oil yielded 23 molecular species of 1-O-alkyl-sn-glycerols with short-chain sn-2 oxoacyl groups, ranging from 4 to 13 carbons, some unsaturated. Autooxidation of human milk fat yielded 1-O-octadecyl-2-(9-oxo)nonanoyl-sn-glycerol, as the major core aldehyde. Because diradylglycerols with short fatty chains are absorbed in the intestine and react with cytidine diphosphate-choline in the enterocytes, it is concluded that formation of such PAF mimics as 1-O-alkyl-2-(omega-oxo)acyl-sn-glycerophosphocholine from unsaturated dietary DAGE is a realistic possibility. Likewise, a C4 core alcohol produced by aldol-keto reduction of a C4 core aldehyde constitutes a dietary precursor of the neuromodulator and recreational drug GHB, which has not been previously pointed out.
authors.affiliation: Biocentrum-DTU, Biochemistry and Nutrition, Centre for Advanced Food Studies, Technical University of Denmark, DK-2800 Lyngby, Denmark.
authors.forename: Karsten
authors.initials: K
authors.lastname: Hartvigsen
authors.forename: Amir
authors.initials: A
authors.lastname: Ravandi
authors.forename: Richard
authors.initials: R
authors.lastname: Harkewicz
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kamido
authors.forename: Klaus
authors.initials: K
authors.lastname: Bukhave
authors.forename: Gunhild
authors.initials: G
authors.lastname: Hølmera
authors.forename: Arnis
authors.initials: A
authors.lastname: Kuksis
mesh_terms: D000447:Aldehydes / Q000737:chemistry; D000818:Animals; D001711:Biotransformation; D005395:Fish Oils / Q000737:chemistry*; D005989:Glycerides / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008049:Lipase / Q000737:chemistry / Q000378:metabolism; D008895:Milk, Human / Q000737:chemistry*; D015394:Molecular Structure; D010972:Platelet Activating Factor / Q000031:analogs & derivatives / Q000096:biosynthesis* / Q000737:chemistry; D012754:Sharks; D012978:Sodium Oxybate / Q000737:chemistry / Q000378:metabolism*; D021241:Spectrometry, Mass, Electrospray Ionization; D013237:Stereoisomerism
chemical_list: D000447:Aldehydes; D005395:Fish Oils; D005989:Glycerides; D010972:Platelet Activating Factor; D012978:Sodium Oxybate; D008049:Lipase