Fatty acid amide hydrolase
|Fatty acid amide hydrolase|
Fatty acid amide hydrolase (FAAH) dimer shown with covalent inhibitor (MAFP, yellow) bound in the active site.
|Locus||Chr. 1 p35-p34|
Fatty acid amide hydrolase or FAAH (EC 18.104.22.168, oleamide hydrolase, anandamide amidohydrolase) is a member of the serine hydrolase family of enzymes. It was first shown to break down anandamide in 1993. In humans, it is encoded by the gene FAAH.
FAAH is an integral membrane hydrolase with a single N-terminal transmembrane domain. In vitro, FAAH has esterase and amidase activity. In vivo, FAAH is the principal catabolic enzyme for a class of bioactive lipids called the fatty acid amides (FAAs). Members of the FAAs include:
- The N-acyltaurines, which are agonists of the transient receptor potential (TRP) family of calcium channels.
FAAH knockout mice display highly elevated (>15-fold) levels of N-acylethanolamines and N-acyltaurines in various tissues. Because of their significantly elevated anandamide levels, FAAH KOs have an analgesic phenotype, showing reduced pain sensation in the hot plate test, the formalin test, and the tail flick test. Finally, because of their impaired ability to degrade anandamide, FAAH KOs also display supersensitivity to exogenous anandamide, a cannabinoid receptor (CB) agonist.
A mutation in FAAH has been linked to drug abuse and dependence. Individuals with the mutation have higher levels of anandamide, the so-called "bliss" molecule, because of lower levels of FAAH, which may reduce anxiety and post-traumatic stress disorder.
Inhibitors and assays
Both non-selective and selective inhibitors of the enzyme have been described. Examples of non-selective inhibitors include PMSF (phenylmethylsulfonylfluoride), MAFP, and ATMK (arachidonoyltrifluoromethylketone). URB597 is a relatively selective, irreversible, carbamate-based inhibitor, though it also inhibits other serine hydrolases, such as carboxylesterases, in peripheral tissues. Urea-based inhibitors such as PF-622 and PF-750 are more potent and more selective inhibitors of FAAH than URB597.
The first crystal structure of FAAH was published in 2002 (PDB ID: 1mt5). Structures of FAAH with drug-like ligands were first reported in 2008, and include covalent (e.g. 2vya, 2wap, 2wj1, 3qkv) and non-covalent (e.g. 3qj9, 4do3) inhibitors.
- Deutsch DG, Chin SA (Sep 1993). "Enzymatic synthesis and degradation of anandamide, a cannabinoid receptor agonist". Biochemical Pharmacology 46 (5): 791–6. doi:10.1016/0006-2952(93)90486-G. PMID 8373432.
- Cravatt BF, Giang DK, Mayfield SP, Boger DL, Lerner RA, Gilula NB (Nov 1996). "Molecular characterization of an enzyme that degrades neuromodulatory fatty-acid amides". Nature 384 (6604): 83–7. doi:10.1038/384083a0. PMID 8900284.
- Giang DK, Cravatt BF (Mar 1997). "Molecular characterization of human and mouse fatty acid amide hydrolases". Proceedings of the National Academy of Sciences of the United States of America 94 (6): 2238–42. doi:10.1073/pnas.94.6.2238. PMC 20071. PMID 9122178.
- Bracey MH, Hanson MA, Masuda KR, Stevens RC, Cravatt BF (Nov 2002). "Structural adaptations in a membrane enzyme that terminates endocannabinoid signaling". Science 298 (5599): 1793–6. doi:10.1126/science.1076535. PMID 12459591.
- Patricelli MP, Cravatt BF (Oct 1999). "Fatty acid amide hydrolase competitively degrades bioactive amides and esters through a nonconventional catalytic mechanism". Biochemistry 38 (43): 14125–30. doi:10.1021/bi991876p. PMID 10571985.
- Cravatt BF, Demarest K, Patricelli MP, Bracey MH, Giang DK, Martin BR, Lichtman AH (Jul 2001). "Supersensitivity to anandamide and enhanced endogenous cannabinoid signaling in mice lacking fatty acid amide hydrolase". Proceedings of the National Academy of Sciences of the United States of America 98 (16): 9371–6. doi:10.1073/pnas.161191698. PMC 55427. PMID 11470906.
- Saghatelian A, Trauger SA, Want EJ, Hawkins EG, Siuzdak G, Cravatt BF (Nov 2004). "Assignment of endogenous substrates to enzymes by global metabolite profiling". Biochemistry 43 (45): 14332–9. doi:10.1021/bi0480335. PMID 15533037.
- Cravatt BF, Prospero-Garcia O, Siuzdak G, Gilula NB, Henriksen SJ, Boger DL, Lerner RA (Jun 1995). "Chemical characterization of a family of brain lipids that induce sleep". Science 268 (5216): 1506–9. doi:10.1126/science.7770779. PMID 7770779.
- Saghatelian A, McKinney MK, Bandell M, Patapoutian A, Cravatt BF (Aug 2006). "A FAAH-regulated class of N-acyl taurines that activates TRP ion channels". Biochemistry 45 (30): 9007–15. doi:10.1021/bi0608008. PMID 16866345.
- Cravatt BF, Lichtman AH (Oct 2004). "The endogenous cannabinoid system and its role in nociceptive behavior". Journal of Neurobiology 61 (1): 149–60. doi:10.1002/neu.20080. PMID 15362158.
- Sipe JC, Chiang K, Gerber AL, Beutler E, Cravatt BF (Jun 2002). "A missense mutation in human fatty acid amide hydrolase associated with problem drug use". Proceedings of the National Academy of Sciences of the United States of America 99 (12): 8394–9. doi:10.1073/pnas.082235799. PMID 12060782.
- "The Feel-Good Gene". New York Times. 6 March 2015. Retrieved 9 March 2015.
- Deutsch DG, Omeir R, Arreaza G, Salehani D, Prestwich GD, Huang Z, Howlett A (Feb 1997). "Methyl arachidonyl fluorophosphonate: a potent irreversible inhibitor of anandamide amidase". Biochemical Pharmacology 53 (3): 255–60. doi:10.1016/S0006-2952(96)00830-1. PMID 9065728.
- De Petrocellis L, Melck D, Ueda N, Maurelli S, Kurahashi Y, Yamamoto S, Marino G, Di Marzo V (Feb 1997). "Novel inhibitors of brain, neuronal, and basophilic anandamide amidohydrolase". Biochemical and Biophysical Research Communications 231 (1): 82–8. doi:10.1006/bbrc.1997.6000. PMID 9070224.
- Koutek B, Prestwich GD, Howlett AC, Chin SA, Salehani D, Akhavan N, Deutsch DG (Sep 1994). "Inhibitors of arachidonoyl ethanolamide hydrolysis". The Journal of Biological Chemistry 269 (37): 22937–40. PMID 8083191.
- Ahn K, Johnson DS, Fitzgerald LR, Liimatta M, Arendse A, Stevenson T, Lund ET, Nugent RA, Nomanbhoy TK, Alexander JP, Cravatt BF (Nov 2007). "Novel mechanistic class of fatty acid amide hydrolase inhibitors with remarkable selectivity". Biochemistry 46 (45): 13019–30. doi:10.1021/bi701378g. PMID 17949010.
- fatty-acid amide hydrolase at the US National Library of Medicine Medical Subject Headings (MeSH)
- Proteopedia FAAH entry - interactive structure (JMOL) of inhibitor-bound FAAH