Anandamide and 2-arachidonoylglycerol inhibit fatty acid amide hydrolase by activating the lipoxygenase pathway of the arachidonate cascade.
Treatment of intact human neuroblastoma CHP100 cells with anandamide (arachidonoylethanolamide, AEA) or 2-arachidonoylglycerol (2-AG) inhibits intracellular fatty acid amide hydrolase (FAAH). This effect was not associated with covalent modifications of FAAH, since specific inhibitors of farnesyltransferase, kinases, phosphatases, glycosyltransferase or nitric oxide synthase were ineffective. Electrophoretic analysis of (33)P-labelled proteins, Western blot with anti-phosphotyrosine antibodies, and glycan analysis of cellular proteins confirmed the absence of covalent modifications of FAAH. The inhibition by AEA was paralleled by an increased arachidonate release, which was not observed upon treatment of cells with linoleoylethanolamide, palmitoylethanolamide, or oleoylethanolamide. Moreover, cell treatment with AEA or 2-AG increased the activity of cyclooxygenase and 5-lipoxygenase, and the hydro(pero)xides generated from arachidonate by lipoxygenase were shown to inhibit FAAH, with inhibition constants in the low micromolar range. Consistently, inhibitors of 5-lipoxygenase, but not those of cyclooxygenase, significantly counteracted the inhibition of FAAH by AEA or 2-AG.
Maccarrone
M
M
Department of Experimental Medicine and Biochemical Sciences, University of Rome "Tor Vergata,", Via di Tor Vergata 135, Rome, I-00133, Italy.
Salvati
S
S
Bari
M
M
Finazzi-Agró
D000581:Amidohydrolases / Q000037:antagonists & inhibitors*; D001094:Arachidonate 5-Lipoxygenase / Q000378:metabolism; D001095:Arachidonic Acids / Q000378:metabolism* / Q000494:pharmacology*; D063388:Endocannabinoids; D004789:Enzyme Activation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004983:Ethanolamines / Q000494:pharmacology; D005989:Glycerides / Q000494:pharmacology*; D006801:Humans; D007700:Kinetics; D008054:Lipid Peroxides / Q000378:metabolism; D008084:Lipoxygenase / Q000378:metabolism*; D016859:Lipoxygenase Inhibitors / Q000494:pharmacology; D009447:Neuroblastoma; D053284:Polyunsaturated Alkamides; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism; D013329:Structure-Activity Relationship; D014407:Tumor Cells, Cultured; D000099252:Fatty Acid Amide Hydrolases
D000581:Amidohydrolases; D001094:Arachidonate 5-Lipoxygenase; D001095:Arachidonic Acids; D063388:Endocannabinoids; D004791:Enzyme Inhibitors; D004983:Ethanolamines; D005989:Glycerides; D008054:Lipid Peroxides; D008084:Lipoxygenase; D016859:Lipoxygenase Inhibitors; D053284:Polyunsaturated Alkamides; D011451:Prostaglandin-Endoperoxide Synthases; D000099252:Fatty Acid Amide Hydrolases; C094503:glyceryl 2-arachidonate; C078814:anandamide