title: Anandamide biosynthesis catalyzed by the phosphodiesterase GDE1 and detection of glycerophospho-N-acyl ethanolamine precursors in mouse brain.
abstract: Anandamide (AEA) is an endogenous ligand of cannabinoid receptors and a well characterized mediator of many physiological processes including inflammation, pain, and appetite. The biosynthetic pathway(s) for anandamide and its N-acyl ethanolamine (NAE) congeners remain enigmatic. Previously, we proposed an enzymatic route for producing NAEs that involves the double-O-deacylation of N-acyl phosphatidylethanolamines (NAPEs) by alpha/beta-hydrolase 4 (ABDH4 or Abh4) to form glycerophospho (GP)-NAEs, followed by conversion of these intermediates to NAEs by an unidentified phosphodiesterase. Here, we report the detection and measurement of GP-NAEs, including the anandamide precursor glycerophospho-N-arachidonoylethanolamine (GP-NArE), as endogenous constituents of mouse brain tissue. Inhibition of the phosphodiesterase-mediated degradation of GP-NAEs ex vivo resulted in a striking accumulation of these lipids in brain extracts, suggesting a rapid endogenous flux through this pathway. Furthermore, we identify the glycerophosphodiesterase GDE1, also known as MIR16, as a broadly expressed membrane enzyme with robust GP-NAE phosphodiesterase activity. Together, these data provide evidence for a multistep pathway for the production of anandamide in the nervous system by the sequential actions of Abh4 and GDE1.
authors.affiliation: Skaggs Institute for Chemical Biology and the Department of Chemical Physiology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, USA.
authors.forename: Gabriel M
authors.initials: GM
authors.lastname: Simon
authors.forename: Benjamin F
authors.initials: BF
authors.lastname: Cravatt
mesh_terms: D000071501:AlkB Homolog 4, Lysine Demethylase; D000818:Animals; D001095:Arachidonic Acids / Q000096:biosynthesis*; D001921:Brain / Q000201:enzymology*; D001923:Brain Chemistry / Q000502:physiology*; D049308:Dioxygenases; D063388:Endocannabinoids; D008297:Male; D051379:Mice; D010714:Phosphatidylethanolamines / Q000378:metabolism*; D010740:Phospholipases / Q000378:metabolism*; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism*; D053284:Polyunsaturated Alkamides
chemical_list: D001095:Arachidonic Acids; D063388:Endocannabinoids; D010714:Phosphatidylethanolamines; D053284:Polyunsaturated Alkamides; C002449:glycerophosphoethanolamine; D049308:Dioxygenases; C585273:ALKBH4 protein, mouse; D000071501:AlkB Homolog 4, Lysine Demethylase; D010740:Phospholipases; D010727:Phosphoric Diester Hydrolases; C038133:glycerophosphodiester phosphodiesterase; C078814:anandamide