Phosphatidylcholine
Encyclopedia
Phosphatidylcholines are a class of phospholipid
s that incorporate choline
as a headgroup.
They are a major component of biological membrane
s and can be easily obtained from a variety of readily available sources such as egg yolk
or soy beans from which they are mechanically extracted or chemically extracted using hexane
. They are also a member of the lecithin
group of yellow-brownish fatty substances occurring in animal and plant tissues.
The name "lecithin" was originally defined from the Greek
lekithos (λεκιθος, egg yolk) by Theodore Nicolas Gobley, a French chemist and pharmacist of the mid-19th century, who applied it to the egg yolk phosphatidylcholine that he identified in 1847 and finally completely described from a chemical structural point of view in 1874. Phosphatidylcholines are such a major component of lecithin that in some contexts the terms are sometimes used as synonyms. However, lecithin extract consists of a mixture of phosphatidylcholine and other compounds. It is also used along with sodium taurocholate
for simulating fed- and fasted-state biorelevant media in dissolution studies of highly-lipophilic drugs.
. It is thought to be transported between membranes within the cell by phosphatidylcholine transfer protein
(PCTP).
Phosphatidylcholine also plays a role in membrane-mediated cell signalling and PCTP activation of other enzymes.
Phospholipase D
catalyzes the hydrolysis of phosphatidylcholine to form phosphatidic acid
(PA), releasing the soluble choline
headgroup into the cytosol
.
. However, a systematic review
of clinical trials in humans found that lecithin or phosphatidylcholine supplementation does not benefit patients with dementia.
, hepatitis B, and hepatitis C
. Phosphatidylcholine administration for chronic
, active hepatitis resulted in significant reduction of disease activity.
, claiming the procedure can break down fat cells, and thus serve as an alternative to liposuction
. It is important to note that while the procedure cites early experiments that showed lipolysis in cases of fat emboli, no peer-reviewed studies have shown any amount of lipolysis even remotely comparable to liposuction.
phosphatidylcholine is an anti-inflammatory, and secondly, is a surface hydrophobicity increasing compound with promising therapeutic potential in the treatment of inflammatory bowel disease.
burden of a diet rich in fats
like phosphatidylcholine, a recent report has linked the microbial catabolites
of phosphatidylcholine with increased atherosclerosis
through the production of choline
, trimethylamine oxide, and betaine.
Phospholipid
Phospholipids are a class of lipids that are a major component of all cell membranes as they can form lipid bilayers. Most phospholipids contain a diglyceride, a phosphate group, and a simple organic molecule such as choline; one exception to this rule is sphingomyelin, which is derived from...
s that incorporate choline
Choline
Choline is a water-soluble essential nutrient. It is usually grouped within the B-complex vitamins. Choline generally refers to the various quaternary ammonium salts containing the N,N,N-trimethylethanolammonium cation....
as a headgroup.
They are a major component of biological membrane
Biological membrane
A biological membrane or biomembrane is an enclosing or separatingmembrane that acts as a selective barrier, within or around a cell. It consists of a lipid bilayer with embedded proteins that may constitute close to 50% of membrane content...
s and can be easily obtained from a variety of readily available sources such as egg yolk
Egg yolk
An egg yolk is a part of an egg which feeds the developing embryo. The egg yolk is suspended in the egg white by one or two spiral bands of tissue called the chalazae...
or soy beans from which they are mechanically extracted or chemically extracted using hexane
Hexane
Hexane is a hydrocarbon with the chemical formula C6H14; that is, an alkane with six carbon atoms.The term may refer to any of four other structural isomers with that formula, or to a mixture of them. In the IUPAC nomenclature, however, hexane is the unbranched isomer ; the other four structures...
. They are also a member of the lecithin
Lecithin
Lecithin is a generic term to designate any group of yellow-brownish fatty substances occurring in animal and plant tissues, and in egg yolk, composed of phosphoric acid, choline, fatty acids, glycerol, glycolipids, triglycerides, and phospholipids .The word lecithin was originally coined in 1847 by...
group of yellow-brownish fatty substances occurring in animal and plant tissues.
The name "lecithin" was originally defined from the Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
lekithos (λεκιθος, egg yolk) by Theodore Nicolas Gobley, a French chemist and pharmacist of the mid-19th century, who applied it to the egg yolk phosphatidylcholine that he identified in 1847 and finally completely described from a chemical structural point of view in 1874. Phosphatidylcholines are such a major component of lecithin that in some contexts the terms are sometimes used as synonyms. However, lecithin extract consists of a mixture of phosphatidylcholine and other compounds. It is also used along with sodium taurocholate
Taurocholic acid
Taurocholic acid, known also as cholaic acid, cholyltaurine, or acidum cholatauricum, is a deliquescent yellowish crystalline bile acid involved in the emulsification of fats. It occurs as a sodium salt in the bile of mammals. It is a conjugate of cholic acid with taurine...
for simulating fed- and fasted-state biorelevant media in dissolution studies of highly-lipophilic drugs.
Function
Phosphatidylcholine is a major constituent of cell membranes. Phosphatidylcholine is more commonly found in the exoplasmic or outer leaflet of a cell membraneCell membrane
The cell membrane or plasma membrane is a biological membrane that separates the interior of all cells from the outside environment. The cell membrane is selectively permeable to ions and organic molecules and controls the movement of substances in and out of cells. It basically protects the cell...
. It is thought to be transported between membranes within the cell by phosphatidylcholine transfer protein
Phosphatidylcholine transfer protein
Phosphatidylcholine transfer protein also known as StAR-related lipid transfer domain protein 2 is a specific intracellular phospholipid binding protein that can transfer phosphatidylcholine between different membranes in the cytosol....
(PCTP).
Phosphatidylcholine also plays a role in membrane-mediated cell signalling and PCTP activation of other enzymes.
Structure
The phospholipid is composed of a choline head group and glycerophosphoric acid with a variety of fatty acids, one being a saturated fatty acid (in the example, here palmitic or hexadecanoic acid, H3C-(CH2)14-COOH; margaric acid identified by Gobley in egg yolk, or heptadecanoic acid H3C-(CH2)15-COOH, also belong to that class); and one being an unsaturated fatty acid (here oleic acid, or 9Z-octadecenoic acid, as in Gobley's original egg yolk lecithin).Phospholipase D
Phospholipase D
Phospholipase D is an enzyme which is located in the plasma membrane and catalyzes the hydrolysis of phosphatidylcholine to form phosphatidic acid , releasing the soluble choline headgroup into the cytosol...
catalyzes the hydrolysis of phosphatidylcholine to form phosphatidic acid
Phosphatidate
Phosphatidic acids are the acid forms of phosphatidates, a part of common phospholipids, major constituents of cell membranes. Phosphatidic acids are the simplest diacyl-glycerophospholipids.-Structure:...
(PA), releasing the soluble choline
Choline
Choline is a water-soluble essential nutrient. It is usually grouped within the B-complex vitamins. Choline generally refers to the various quaternary ammonium salts containing the N,N,N-trimethylethanolammonium cation....
headgroup into the cytosol
Cytosol
The cytosol or intracellular fluid is the liquid found inside cells, that is separated into compartments by membranes. For example, the mitochondrial matrix separates the mitochondrion into compartments....
.
Senescence
Phosphatidylcholine is a vital substance that is in every cell in the human body. Thus some researchers have used mutant mouse models with severe oxidative damage as a model of "accelerated aging" to investigate the possible role of phosphatidylcholine supplementation as a way of slowing down aging-related processes. and improving brain functioning and memory capacity in dementiaDementia
Dementia is a serious loss of cognitive ability in a previously unimpaired person, beyond what might be expected from normal aging...
. However, a systematic review
Systematic review
A systematic review is a literature review focused on a research question that tries to identify, appraise, select and synthesize all high quality research evidence relevant to that question. Systematic reviews of high-quality randomized controlled trials are crucial to evidence-based medicine...
of clinical trials in humans found that lecithin or phosphatidylcholine supplementation does not benefit patients with dementia.
Liver repair
Recent studies point to the many potential benefits of phosphatidylcholine for liver repair. One study shows phosphatidylcholine's healing effect with hepatitis AHepatitis A
Hepatitis A is an acute infectious disease of the liver caused by the hepatitis A virus , an RNA virus, usually spread the fecal-oral route; transmitted person-to-person by ingestion of contaminated food or water or through direct contact with an infectious person...
, hepatitis B, and hepatitis C
Hepatitis C
Hepatitis C is an infectious disease primarily affecting the liver, caused by the hepatitis C virus . The infection is often asymptomatic, but chronic infection can lead to scarring of the liver and ultimately to cirrhosis, which is generally apparent after many years...
. Phosphatidylcholine administration for chronic
Chronic
Chronic may refer to:* Chronic , a disease that is long-lasting and reoccurring.* Chronic toxicity, a substance with toxic effects after continuous or repeated exposure* The Chronic, a 1992 album by Dr. Dre...
, active hepatitis resulted in significant reduction of disease activity.
Lipolysis
Some organizations promote the use of injected phosphatidylcholine, otherwise known as injection lipolysisInjection lipolysis
Injection lipolysis is a controversial cosmetic procedure in which drug mixtures are injected into patients with the goal of breaking down fat. This practice, using drugs generally based on phosphatidylcholine and deoxycholate , evolved from the initial intravenous use of those drug formulations to...
, claiming the procedure can break down fat cells, and thus serve as an alternative to liposuction
Liposuction
Liposuction, also known as lipoplasty , liposculpture suction lipectomy or simply lipo is a cosmetic surgery operation that removes fat from many different sites on the human body...
. It is important to note that while the procedure cites early experiments that showed lipolysis in cases of fat emboli, no peer-reviewed studies have shown any amount of lipolysis even remotely comparable to liposuction.
Ulcerative colitis
Phase IIa/b clinical trials performed at the Heidelberg University Hospital have shown that delayed releaseDelayed release
A delayed release or late release refers to the relatively late release of a product to the public.-In film:In the film industry a release can be postponed due to the sometimes difficult transition of the production and/or post-production to the sales and distribution phase of the film production...
phosphatidylcholine is an anti-inflammatory, and secondly, is a surface hydrophobicity increasing compound with promising therapeutic potential in the treatment of inflammatory bowel disease.
Possible health risks
In addition to the increased caloricCalorie
The calorie is a pre-SI metric unit of energy. It was first defined by Nicolas Clément in 1824 as a unit of heat, entering French and English dictionaries between 1841 and 1867. In most fields its use is archaic, having been replaced by the SI unit of energy, the joule...
burden of a diet rich in fats
Fats
Fats may refer to:*Fat, a generic term for a class of lipids in biochemistry*Fats Domino, rock and roll pianist*Fats Waller, jazz pianist*Fats Navarro, jazz trumpeter*Singing Fats, master of ceremonies*Obesity...
like phosphatidylcholine, a recent report has linked the microbial catabolites
Catabolism
Catabolism is the set of metabolic pathways that break down molecules into smaller units and release energy. In catabolism, large molecules such as polysaccharides, lipids, nucleic acids and proteins are broken down into smaller units such as monosaccharides, fatty acids, nucleotides, and amino...
of phosphatidylcholine with increased atherosclerosis
Atherosclerosis
Atherosclerosis is a condition in which an artery wall thickens as a result of the accumulation of fatty materials such as cholesterol...
through the production of choline
Choline
Choline is a water-soluble essential nutrient. It is usually grouped within the B-complex vitamins. Choline generally refers to the various quaternary ammonium salts containing the N,N,N-trimethylethanolammonium cation....
, trimethylamine oxide, and betaine.
See also
- CDP choline
- LysophosphatidylcholineLysophosphatidylcholineLysophosphatidylcholines , also called lysolecithins, are a class of chemical compounds which are derived from phosphatidylcholines. They result from partial hydrolysis of phosphatidylcholines, which removes one of the fatty acid groups. The hydrolysis is generally the result of the enzymatic...
- Theodore Nicolas Gobley, discoverer of egg yolk lecithin, the first in history phosphatidylcholine
- Saturated fatty acid
- Unsaturated fatty acid
External links
- http://www.kvue.com/news/top/stories/110507kvuelipodissolve-mm.1e0189bdb.html