A structure–activity relationship study on N-arachidonoyl-amino acids as possible endogenous inhibitors of fatty acid amide hydrolase

doi:10.1016/j.bbrc.2003.12.075

Biochemical and Biophysical Research Communications

Volume 314, Issue 1, 30 January 2004, Pages 192-196

https://doi.org/10.1016/j.bbrc.2003.12.075 Get rights and content

Abstract

N-arachidonoyl-glycine (NAGly) has been recently identified in rodent tissues and found to exhibit analgesic activity in vivo. NAGly is a potent inhibitor of the fatty acid amide hydrolase (FAAH), the enzyme primarily responsible for the degradation of the endocannabinoid N-arachidonoyl-ethanolamine (anandamide), and was shown recently to elevate the blood levels of the this analgesic compound. We have synthesized several N-arachidonoyl-amino acids of potential natural occurrence, as well as the d- and l-isomers of N-arachidonoyl-alanine, and have tested their activity on FAAH preparations from mouse, rat, and human cell lines, and from mouse or rat brain. The results indicate that the relative potency and enantioselectivity of N-arachidonoyl-amino acids as FAAH inhibitors depend on the animal species. Thus, whilst NAGly is the most potent compound on the rat and mouse enzymes, N-arachidonoyl-isoleucine is active only on human FAAH and N-arachidonoyl-alanine enantiomers show a varying degree of potency. Taken together, these data support the view that an enhancement of endogenous anandamide levels underlies in part the analgesic effects of NAGly in rodents.

Section snippets

Materials and methods

Synthesis of N-arachidonoyl-amino acids. Briefly, the compounds with general structure shown in Fig. 1, were obtained from commercially available amino acid tert-butyl esters by acylation with arachidonic acid with the DEPC (diethyl cyanophosphonate)/TEA (triethylamine) protocol, followed by de-protection with TFA (trifluoroacetic acid) in CH₂Cl₂.The compounds were purified by gravity column chromatography, and their structure and purity was assessed by proton nuclear magnetic resonance.

The

Results and discussion

The fatty acid amide, NAGly, is an endogenous compound with a widespread but nonetheless heterogeneous distribution in bovine and rat tissues, and with a potent analgesic and anti-inflammatory activity [21]. This compound seems to accompany the endocannabinoid anandamide in many tissues, and preliminary observations carried out in rat uterus indicate that its levels as well as those, normally lower, of anandamide might be regulated by estrogens [26]. Whilst no receptor has been identified for

Acknowledgements

This work was partly supported by MURST (Grant 3933 to VDM) and Grant (DA 09017) from The National Institute on Drug Abuse to SHB.

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¹: These authors contributed equally to this study.

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A structure–activity relationship study on N-arachidonoyl-amino acids as possible endogenous inhibitors of fatty acid amide hydrolase

Abstract

Section snippets

Materials and methods

Results and discussion

Acknowledgements

Prog. Lipid Res.

Biochim. Biophys. Acta

Prostaglandins Leukot. Essent. Fatty Acids

Biochem. Pharmacol.

Biochem. Biophys. Res. Commun.

J. Biol. Chem.

Arch. Biochem. Biophys.

J. Biol. Chem.

J. Biol. Chem.

Gene

J. Biol. Chem.

Prostaglandins Other Lipid Mediat.

Biochem. Pharmacol.