ethanolamide

Ethanolamides are a class of organic compounds formed from ethanolamine and fatty acids, also known as N-acyl ethanolamines. They share a general structure in which a fatty acyl group is linked by an amide bond to ethanolamine, giving the motif R-CO-NH-CH2-CH2-OH. They are lipid signaling molecules found in various tissues and can be produced on demand in cells.

Well-known members of the family include anandamide (arachidonoylethanolamide, AEA), palmitoylethanolamide (PEA), and oleoylethanolamide (OEA). Anandamide is a ligand for the endocannabinoid receptors CB1 and CB2 and can activate the TRPV1 channel, while PEA and OEA do not serve as primary ligands for cannabinoid receptors but influence signaling through other targets such as peroxisome proliferator-activated receptor alpha (PPAR-α). Other N-acyl ethanolamines with different fatty acyl chains also occur in organisms.

Biosynthesis and degradation occur via distinct enzymatic pathways. N-acyl ethanolamines are formed by transfer of a fatty acyl group to ethanolamine, often through intermediates such as N-acylphosphatidylethanolamines. Degradation is predominantly carried out by fatty acid amide hydrolase (FAAH), which hydrolyzes AEA and related compounds, and by N-acylethanolamine acid amidase (NAAA), which preferentially degrades some PEA species.

Biological significance includes modulation of pain, inflammation, appetite, and energy metabolism. Because of their roles in endocannabinoid and related signaling pathways, ethanolamides are investigated for potential therapeutic applications and as tools to study lipid signaling mechanisms, with ongoing research into their pharmacology and physiological functions.