title: Robust hydrolysis of prostaglandin glycerol esters by human monoacylglycerol lipase (MAGL).
abstract: The primary route of inactivation of the endocannabinoid 2-arachidonoylglycerol in the central nervous system is through enzymatic hydrolysis, mainly carried out by monoacylglycerol lipase (MAGL), along with a small contribution by the α/β-hydrolase domain (ABHD) proteins ABHD6 and ABHD12. Recent methodological progress allowing kinetic monitoring of glycerol liberation has facilitated substrate profiling of the human endocannabinoid hydrolases, and these studies have revealed that the three enzymes have distinct monoacylglycerol substrate and isomer preferences. Here, we have extended this substrate profiling to cover four prostaglandin glycerol esters, namely, 15-deoxy-Δ(12,14)-prostaglandin J2-2-glycerol (15d-PGJ2-G), PGD2-G, PGE2-G, and PGF2 α-G. We found that the three enzymes hydrolyzed the tested substrates, albeit with distinct rates and preferences. Although human ABHD12 (hABHD12) showed only marginal activity toward PGE2-G, hABHD6 preferentially hydrolyzed PGD2-G, and human MAGL (hMAGL) robustly hydrolyzed all four. This was particularly intriguing for MAGL activity toward 15d-PGJ2-G whose hydrolysis rate rivaled that of the best monoacylglycerol substrates. Molecular modeling studies combined with kinetic analysis supported favorable interaction with the hMAGL active site. Long and short MAGL isoforms shared a similar substrate profile, and hMAGL hydrolyzed 15d-PGJ2-G also in living cells. The ability of 15d-PGJ2-G to activate the canonical nuclear factor erythroid 2-related factor (Nrf2) signaling pathway used by 15d-PGJ2 was assessed, and these studies revealed for the first time that 15d-PGJ2 and 15d-PGJ2-G similarly activated Nrf2 signaling as well as transcription of target genes of this pathway. Our study challenges previous claims regarding the ability of MAGL to catalyze PG-G hydrolysis and extend the MAGL substrate profile beyond the classic monoacylglycerols.
authors.affiliation: School of Medicine, Institute of Biomedicine (J.R.S., D.N-P., Te.P., J.T.L.), A.I. Virtanen Institute for Molecular Sciences (E.K., A-L.L.), School of Pharmacy (Ta.P., Te.P., M.L., T.L., T.N., A.P.), Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.
authors.forename: Juha R
authors.initials: JR
authors.lastname: Savinainen
authors.affiliation: School of Medicine, Institute of Biomedicine (J.R.S., D.N-P., Te.P., J.T.L.), A.I. Virtanen Institute for Molecular Sciences (E.K., A-L.L.), School of Pharmacy (Ta.P., Te.P., M.L., T.L., T.N., A.P.), Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.
authors.forename: Emilia
authors.initials: E
authors.lastname: Kansanen
authors.affiliation: School of Medicine, Institute of Biomedicine (J.R.S., D.N-P., Te.P., J.T.L.), A.I. Virtanen Institute for Molecular Sciences (E.K., A-L.L.), School of Pharmacy (Ta.P., Te.P., M.L., T.L., T.N., A.P.), Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.
authors.forename: Tatu
authors.initials: T
authors.lastname: Pantsar
authors.affiliation: School of Medicine, Institute of Biomedicine (J.R.S., D.N-P., Te.P., J.T.L.), A.I. Virtanen Institute for Molecular Sciences (E.K., A-L.L.), School of Pharmacy (Ta.P., Te.P., M.L., T.L., T.N., A.P.), Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.
authors.forename: Dina
authors.initials: D
authors.lastname: Navia-Paldanius
authors.affiliation: School of Medicine, Institute of Biomedicine (J.R.S., D.N-P., Te.P., J.T.L.), A.I. Virtanen Institute for Molecular Sciences (E.K., A-L.L.), School of Pharmacy (Ta.P., Te.P., M.L., T.L., T.N., A.P.), Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.
authors.forename: Teija
authors.initials: T
authors.lastname: Parkkari
authors.affiliation: School of Medicine, Institute of Biomedicine (J.R.S., D.N-P., Te.P., J.T.L.), A.I. Virtanen Institute for Molecular Sciences (E.K., A-L.L.), School of Pharmacy (Ta.P., Te.P., M.L., T.L., T.N., A.P.), Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.
authors.forename: Marko
authors.initials: M
authors.lastname: Lehtonen
authors.affiliation: School of Medicine, Institute of Biomedicine (J.R.S., D.N-P., Te.P., J.T.L.), A.I. Virtanen Institute for Molecular Sciences (E.K., A-L.L.), School of Pharmacy (Ta.P., Te.P., M.L., T.L., T.N., A.P.), Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.
authors.forename: Tuomo
authors.initials: T
authors.lastname: Laitinen
authors.affiliation: School of Medicine, Institute of Biomedicine (J.R.S., D.N-P., Te.P., J.T.L.), A.I. Virtanen Institute for Molecular Sciences (E.K., A-L.L.), School of Pharmacy (Ta.P., Te.P., M.L., T.L., T.N., A.P.), Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.
authors.forename: Tapio
authors.initials: T
authors.lastname: Nevalainen
authors.affiliation: School of Medicine, Institute of Biomedicine (J.R.S., D.N-P., Te.P., J.T.L.), A.I. Virtanen Institute for Molecular Sciences (E.K., A-L.L.), School of Pharmacy (Ta.P., Te.P., M.L., T.L., T.N., A.P.), Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.
authors.forename: Antti
authors.initials: A
authors.lastname: Poso
authors.affiliation: School of Medicine, Institute of Biomedicine (J.R.S., D.N-P., Te.P., J.T.L.), A.I. Virtanen Institute for Molecular Sciences (E.K., A-L.L.), School of Pharmacy (Ta.P., Te.P., M.L., T.L., T.N., A.P.), Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland.
authors.forename: Anna-Liisa
authors.initials: AL
authors.lastname: Levonen
authors.affiliation: School of Medicine, Institute of Biomedicine (J.R.S., D.N-P., Te.P., J.T.L.), A.I. Virtanen Institute for Molecular Sciences (E.K., A-L.L.), School of Pharmacy (Ta.P., Te.P., M.L., T.L., T.N., A.P.), Faculty of Health Sciences, University of Eastern Finland, Kuopio, Finland jarmo.laitinen@uef.fi.
authors.forename: Jarmo T
authors.initials: JT
authors.lastname: Laitinen
mesh_terms: D020134:Catalytic Domain / Q000502:physiology; D002478:Cells, Cultured; D063388:Endocannabinoids / Q000378:metabolism; D004952:Esters / Q000378:metabolism*; D005990:Glycerol / Q000378:metabolism*; D057809:HEK293 Cells; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D006867:Hydrolases / Q000378:metabolism; D006868:Hydrolysis; D007700:Kinetics; D008994:Monoacylglycerol Lipases / Q000378:metabolism*; D050178:Monoglycerides / Q000378:metabolism; D051267:NF-E2-Related Factor 2 / Q000378:metabolism; D015230:Prostaglandin D2 / Q000031:analogs & derivatives / Q000378:metabolism; D011453:Prostaglandins / Q000378:metabolism*; D020033:Protein Isoforms / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology
chemical_list: C477819:15-deoxyprostaglandin J2; D063388:Endocannabinoids; D004952:Esters; D050178:Monoglycerides; D051267:NF-E2-Related Factor 2; C495635:NFE2L2 protein, human; D011453:Prostaglandins; D020033:Protein Isoforms; D006867:Hydrolases; D008994:Monoacylglycerol Lipases; D005990:Glycerol; D015230:Prostaglandin D2