title: A FAAH-regulated class of N-acyl taurines that activates TRP ion channels.
abstract: Fatty acid amide hydrolase (FAAH) is an integral membrane enzyme that catabolizes several bioactive lipids in vivo. Most of the physiological substrates of FAAH characterized to date belong to the N-acyl ethanolamine (NAE) class of fatty acid amides, including the endocannabinoid anandamide, the anti-inflammatory lipid N-palmitoyl ethanolamine, and the satiating factor N-oleoyl ethanolamine. We recently identified a second structural class of fatty acid amides regulated by FAAH in vivo: the N-acyl taurines (NATs). Global metabolite profiling revealed high concentrations of long chain (> or = C20) saturated NATs in the central nervous system (CNS) of FAAH(-/-) mice. Here, we use metabolite profiling to characterize the FAAH-NAT system in peripheral mouse tissues. Livers and kidneys of FAAH(-/-) mice possessed dramatic elevations in NATs, which, in contrast to those detected in the CNS, were enriched in polyunsaturated acyl chains (e.g., C20:4, C22:6). Peripheral NATs rose more than 10-fold within 1 h following pharmacological inactivation of FAAH and reached levels up to approximately 5000 pmol/g tissue (C22:6 in kidney), implicating a constitutive and highly active pathway for NAT metabolism in which FAAH plays an integral part. Interestingly, NATs were found to activate multiple members of the transient receptor potential (TRP) family of calcium channels, including TRPV1 and TRPV4, which are both expressed in kidney. The dramatic elevation in endogenous levels of NATs following acute or chronic inactivation of FAAH, in conjunction with the pharmacological effects of these lipids on TRP channels, suggests the existence of a second major lipid signaling system regulated by FAAH in vivo.
authors.affiliation: Department of Cell Biology, The Skaggs Institute for Chemical Biology, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
authors.forename: Alan
authors.initials: A
authors.lastname: Saghatelian
authors.forename: Michele K
authors.initials: MK
authors.lastname: McKinney
authors.forename: Michael
authors.initials: M
authors.lastname: Bandell
authors.forename: Ardem
authors.initials: A
authors.lastname: Patapoutian
authors.forename: Benjamin F
authors.initials: BF
authors.lastname: Cravatt
mesh_terms: D000581:Amidohydrolases / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000172:deficiency / Q000235:genetics; D000818:Animals; D001549:Benzamides / Q000008:administration & dosage; D016466:CHO Cells; D002219:Carbamates / Q000008:administration & dosage; D006224:Cricetinae; D004791:Enzyme Inhibitors / Q000008:administration & dosage; D051379:Mice; D018345:Mice, Knockout; D050916:TRPV Cation Channels / Q000737:chemistry / Q000378:metabolism*; D013654:Taurine / Q000031:analogs & derivatives* / Q000737:chemistry* / Q000502:physiology; D014018:Tissue Distribution / Q000187:drug effects / Q000502:physiology; D000099252:Fatty Acid Amide Hydrolases
chemical_list: D000581:Amidohydrolases; D001549:Benzamides; D002219:Carbamates; D004791:Enzyme Inhibitors; D050916:TRPV Cation Channels; D013654:Taurine; D000099252:Fatty Acid Amide Hydrolases; C500528:cyclohexyl carbamic acid 3'-carbamoylbiphenyl-3-yl ester