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Savinainen JR, Kansanen E, Pantsar T, Navia-Paldanius D, Parkkari T, Lehtonen M, Laitinen T, Nevalainen T, Poso A, Levonen AL, Laitinen JT. Robust hydrolysis of prostaglandin glycerol esters by human monoacylglycerol lipase (MAGL). Mol Pharmacol 2014; 86:522-35. [PMID: 25140003 DOI: 10.1124/mol.114.094284] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
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.
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Affiliation(s)
- Juha R Savinainen
- 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
| | - Emilia Kansanen
- 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
| | - Tatu Pantsar
- 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
| | - Dina Navia-Paldanius
- 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
| | - Teija Parkkari
- 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
| | - Marko Lehtonen
- 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
| | - Tuomo Laitinen
- 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
| | - Tapio Nevalainen
- 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
| | - Antti Poso
- 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
| | - Anna-Liisa Levonen
- 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 T Laitinen
- 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
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Dócs K, Hegyi Z, Holló K, Kis G, Hegedűs K, Antal M. Selective axonal and glial distribution of monoacylglycerol lipase immunoreactivity in the superficial spinal dorsal horn of rodents. Brain Struct Funct 2014; 220:2625-37. [PMID: 24942136 DOI: 10.1007/s00429-014-0813-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2014] [Accepted: 05/27/2014] [Indexed: 11/29/2022]
Abstract
The importance of 2-AG-mediated endogenous cannabinoid signaling in spinal pain control has recently been well substantiated. Although the degradation of 2-AG seems to be essential in cannabinoid-mediated spinal nociceptive information processing, no experimental data are available about the cellular distribution of monoacylglycerol lipase (MGL), the main degrading enzyme of 2-AG in the spinal dorsal horn. Thus, here we investigated the cellular distribution of MGL in laminae I-II of the spinal gray matter with immunocytochemical methods and revealed an abundant immunoreactivity for MGL in the rodent superficial spinal dorsal horn. We addressed the co-localization of MGL with markers of peptidergic and non-peptidergic primary afferents, axon terminals of putative glutamatergic and GABAergic spinal neurons, as well as astrocytic and microglial profiles, and we found that nearly 17 % of the peptidergic (immunoreactive for CGRP), a bit more than 10 % of the axon terminals of putative glutamatergic spinal neurons (immunoreactive for VGLUT2), and approximately 20 % of the astrocytic (immunoreactive for GFAP) profiles were immunolabeled for MGL. On the other hand, however, axon terminals of non-peptidergic (binding isolectin-B4) nociceptive primary afferents and putative inhibitory spinal neurons (immunoreactive for VGAT) as well as microglial (immunoreactive for CD11b) profiles showed negligible immunostaining for MGL. The results suggest that only nociceptive inputs arriving through a population of CGRP immunoreactive fibers are modulated by the spinal DGLα-MGL pathway. We also postulate that the DGLα-MGL signaling pathway may modulate spinal excitatory but not inhibitory neural circuits.
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Affiliation(s)
- Klaudia Dócs
- Department of Anatomy, Histology and Embryology, Faculty of Medicine, Medical and Health Science Center, University of Debrecen, Nagyerdei krt 98, Debrecen, 4032, Hungary
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