''N''-Acylphosphatidylethanolamines (NAPEs) are
hormone
A hormone (from the Ancient Greek, Greek participle , "setting in motion") is a class of cell signaling, signaling molecules in multicellular organisms that are sent to distant organs or tissues by complex biological processes to regulate physio ...
s released by the
small intestine
The small intestine or small bowel is an organ (anatomy), organ in the human gastrointestinal tract, gastrointestinal tract where most of the #Absorption, absorption of nutrients from food takes place. It lies between the stomach and large intes ...
into the
bloodstream
In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. It includes the cardiovascular system, or vascular system, that consists of the heart an ...
when it processes
fat
In nutrition science, nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such chemical compound, compounds, most commonly those that occur in living beings or in food.
The term often refers specif ...
. NAPEs travel to the
hypothalamus
The hypothalamus (: hypothalami; ) is a small part of the vertebrate brain that contains a number of nucleus (neuroanatomy), nuclei with a variety of functions. One of the most important functions is to link the nervous system to the endocrin ...
in the brain and suppress
appetite
Appetite is the desire to eat food items, usually due to hunger. Appealing foods can stimulate appetite even when hunger is absent, although appetite can be greatly reduced by satiety. Appetite exists in all higher life-forms, and serves to reg ...
. This mechanism could be relevant for treating
obesity
Obesity is a medical condition, considered by multiple organizations to be a disease, in which excess Adipose tissue, body fat has accumulated to such an extent that it can potentially have negative effects on health. People are classifi ...
.
[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 primarily in the ''Cannabis'' plant or as synthetic compounds. The most notable cannabinoid is the phytocannabinoid tetrahydrocannabinol (THC) (delta-9-THC), the primary psychoact ...
.
NAPEs are formed from
phosphatidylethanolamines
Phosphatidylethanolamine (PE) is a class of phospholipids found in biological membranes. They are synthesized by the addition of cytidine diphosphate-ethanolamine to diglycerides, releasing cytidine monophosphate. ''S''-Adenosyl methionine can ...
, 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 typi ...
characteristic of nervous tissue. After being cleaved by
phospholipases, NAPEs can be transformed into
''N''-acylethanolamines, including the endocannabinoid
anandamide
Anandamide (ANA), also referred to as ''N''-arachidonoylethanolamine (AEA) is a fatty acid neurotransmitter belonging to the fatty acid derivative group known as N-acylethanolamine (NAE). Anandamide takes its name from the Sanskrit word ''ananda ...
.
While
NAPE-PLD NAPE-PLD may refer to:
*
* N-acyl phosphatidylethanolamine-specific phospholipase D, an enzyme
* N-acetylphosphatidylethanolamine-hydrolysing phospholipase D, an enzyme
{{enzyme index ...
is the enzyme responsible for catalyzing said release of N-acylethanolamine (NAE) from N-acyl-phosphatidylethanolamine (NAPE), this specific subtype of
phospholipase D
Phospholipase D (PLD) (EC 3.1.4.4; also known as lipophosphodiesterase II, lecithinase D, choline phosphatase; systematic name: phosphatidylcholine phosphatidohydrolase) is an anesthetic-sensitive and mechanosensitive enzyme of the phospholipa ...
is not responsible for the formation of the anandamide.
The crystal structure of human
N-acyl phosphatidylethanolamine-specific phospholipase D
N-acyl phosphatidylethanolamine phospholipase D (NAPE-PLD) is an enzyme that catalyzes the release of N-acylethanolamine (NAE) from N-acyl-phosphatidylethanolamine (NAPE). This is a major part of the process that converts ordinary lipids into c ...
(NAPE-PLD) reveals how this membrane enzyme generates
anandamide
Anandamide (ANA), also referred to as ''N''-arachidonoylethanolamine (AEA) is a fatty acid neurotransmitter belonging to the fatty acid derivative group known as N-acylethanolamine (NAE). Anandamide takes its name from the Sanskrit word ''ananda ...
and other bioactive lipid amides from membrane NAPEs.
A hydrophobic cavity in
NAPE-PLD NAPE-PLD may refer to:
*
* N-acyl phosphatidylethanolamine-specific phospholipase D, an enzyme
* N-acetylphosphatidylethanolamine-hydrolysing phospholipase D, an enzyme
{{enzyme index ...
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 in peroxisomes. Bile acids are conjugated with taurine or glycine residues to give anions called bile ...
bind the membrane enzyme, enhancing dimer assembly and enabling catalysis. These findings suggest NAPE-PLD might orchestrate a direct crosstalk between
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 in peroxisomes. Bile acids are conjugated with taurine or glycine residues to give anions called bile ...
and lipid amide signals.
See also
*
Ghrelin
Ghrelin (; or lenomorelin, INN) is a hormone primarily produced by enteroendocrine cells of the gastrointestinal tract, especially the stomach, and is often called a "hunger hormone" because it increases the drive to eat. Blood levels of ghrel ...
*
Leptin
Leptin (from Ancient Greek, Greek λεπτός ''leptos'', "thin" or "light" or "small"), also known as obese protein, is a protein hormone predominantly made by adipocytes (cells of adipose tissue). Its primary role is likely to regulate long ...
References
{{DEFAULTSORT:Acylphosphatidylethanolamine, N-
Intestinal hormones
Fatty acid amides