''N''-Acylphosphatidylethanolamines (NAPEs) are

hormone A hormone (from the Greek participle , "setting in motion") is a class of signaling molecules in multicellular organisms that are sent to distant organs by complex biological processes to regulate physiology and behavior. Hormones are require ...

s released by the small intestine into the

bloodstream The blood circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the entire body of a human or other vertebrate. It includes the cardiovascular system, or vascular system, tha ...

when it processes

fat In nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such compounds, most commonly those that occur in living beings or in food. The term often refers specifically to triglycerides (triple est ...

. NAPEs travel to the

hypothalamus The hypothalamus () is a part of the brain that contains a number of small nuclei with a variety of functions. One of the most important functions is to link the nervous system to the endocrine system via the pituitary gland. The hypothalamu ...

in the brain and suppress appetite. This mechanism could be relevant for treating

obesity Obesity is a medical condition, sometimes considered a disease, in which excess body fat has accumulated to such an extent that it may negatively affect health. People are classified as obese when their body mass index (BMI)—a person's ...

.Dunham, Will (Nov 26, 2008).
Gut chemical may inspire new way to fight obesity
. ''Reuters'' Accessed 27 Nov. 2008

Endocannabinoid precursor

''N''-Acylphosphatidylethanolamines are also an important intermediaries in the biosynthesis of

endocannabinoids Cannabinoids () are several structural classes of compounds found in the cannabis plant primarily and most animal organisms (although insects lack such receptors) or as synthetic compounds. The most notable cannabinoid is the phytocannabinoid tet ...

. NAPEs are formed from phosphatidylethanolamines, a group of cell membrane

phospholipids Phospholipids, are a class of lipids whose molecule has a hydrophilic "head" containing a phosphate group and two hydrophobic "tails" derived from fatty acids, joined by an alcohol residue (usually a glycerol molecule). Marine phospholipids t ...

characteristic of nervous tissue. After being cleaved by

phospholipases A phospholipase is an enzyme that hydrolyzes phospholipids into fatty acids and other lipophilic substances. Acids trigger the release of bound calcium from cellular stores and the consequent increase in free cytosolic Ca2+, an essential step in ...

, NAPEs can be transformed into ''N''-acylethanolamines, including the endocannabinoid

anandamide Anandamide (ANA), also known as ''N''-arachidonoylethanolamine (AEA), is a fatty acid neurotransmitter. Anandamide was the first endocannabinoid to be discovered: it participates in the body's endocannabinoid system by binding to cannabinoid r ...

. While NAPE-PLD is the enzyme responsible for catalyzing said release of N-acylethanolamine (NAE) from N-acyl-phosphatidylethanolamine (NAPE), this specific subtype of phospholipase D is not responsible for the formation of the anandamide. The crystal structure of human N-acyl phosphatidylethanolamine-specific phospholipase D (NAPE-PLD) reveals how this membrane enzyme generates

and other bioactive lipid amides from membrane NAPEs. A hydrophobic cavity in NAPE-PLD provides an entryway for the substrate NAPE into the active site, where a binuclear zinc center orchestrates its hydrolysis. Unexpectedly, the structure unveils

bile acids Bile acids are steroid acids found predominantly in the bile of mammals and other vertebrates. Diverse bile acids are synthesized in the liver. Bile acids are conjugated with taurine or glycine residues to give anions called bile salts. Prima ...

bind the membrane enzyme, enhancing dimer assembly and enabling catalysis. These findings suggest NAPE-PLD might orchestrate a direct crosstalk between

and lipid amide signals.

References

{{DEFAULTSORT:Acylphosphatidylethanolamine, N- Intestinal hormones Fatty acid amides

Endocannabinoid precursor

See also

References