Phosphatidylserine
Encyclopedia
Phosphatidylserine is a phospholipid
component, usually kept on the inner-leaflet (the cytosolic side) of cell membranes by an enzyme called flippase
. When a cell undergoes apoptosis
, phosphatidylserine is no longer restricted to the cytosolic part of the membrane, but becomes exposed on the surface of the cell.
, however, modern studies and commercially available products are made from soybean
s. The fatty acids attached to the serine in the soy product are not identical to those in the bovine product, which is also impure. Preliminary studies in rats indicate that the soy product is at least as effective as that of bovine origin.
However, later clinical trials in humans found that "a daily supplement of S-PS (soybean derived PS) does not affect memory or other cognitive functions in older individuals with memory complaints."
On May 13, 2003, the U.S. Food and Drug Administration
stated "based on its evaluation of the totality of the publicly available scientific evidence, the agency concludes that there is not significant scientific agreement among qualified experts that a relationship exists between phosphatidylserine and reduced risk of dementia or cognitive dysfunction." FDA also stated "of the 10 intervention studies that formed the basis of FDA's evaluation, all were seriously flawed or limited in their reliability in one or more ways." It concludes that "most of the evidence does not support a relationship between phosphatidylserine and reduced risk of dementia or cognitive dysfunction, and that the evidence that does support such a relationship is very limited and preliminary." FDA did, however give "qualified health claim" status to phosphatidylserine, stating that, "Consumption of phosphatidylserine may reduce the risk of dementia in the elderly" and "Consumption of phosphatidylserine may reduce the risk of cognitive dysfunction in the elderly."
levels. PS supplementation promotes a desirable hormonal balance for athletes and might attenuate the physiological deterioration that accompanies overtraining and/or overstretching. In recent studies, PS has been shown to enhance mood in a cohort of young people during mental stress and to improve accuracy during tee-off by increasing the stress resistance of golf
ers.
.
) and is a safe nutritional supplement for older persons if taken up to a dosage of 200 mg three times daily. Phosphatidylserine has been shown to reduce specific immune response
in mice
.
Table 1. PS content in different foods.
The average daily PS intake from the diet in Western countries is estimated to be 130 mg.
or in vivo
. Another PS binding protein is Mfge8
.
-labeled annexin-A5 enables distinction between malignant and benign tumours whose pathology includes a high rate of cell division and apoptosis in malignant compared with a low rate of apoptosis in benign tumors.
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...
component, usually kept on the inner-leaflet (the cytosolic side) of cell membranes by an enzyme called flippase
Flippase
Flippases are a family of transmembrane lipid transporter enzymes located in the membrane responsible for aiding the movement of phospholipid molecules between the two leaflets that compose a cell's membrane...
. When a cell undergoes apoptosis
Apoptosis
Apoptosis is the process of programmed cell death that may occur in multicellular organisms. Biochemical events lead to characteristic cell changes and death. These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, and chromosomal DNA fragmentation...
, phosphatidylserine is no longer restricted to the cytosolic part of the membrane, but becomes exposed on the surface of the cell.
Memory and cognition
Early studies of phosphatidylserine distilled the chemical from bovine brain. Because of concerns about Bovine Spongiform EncephalopathyBovine spongiform encephalopathy
Bovine spongiform encephalopathy , commonly known as mad-cow disease, is a fatal neurodegenerative disease in cattle that causes a spongy degeneration in the brain and spinal cord. BSE has a long incubation period, about 30 months to 8 years, usually affecting adult cattle at a peak age onset of...
, however, modern studies and commercially available products are made from soybean
Soybean
The soybean or soya bean is a species of legume native to East Asia, widely grown for its edible bean which has numerous uses...
s. The fatty acids attached to the serine in the soy product are not identical to those in the bovine product, which is also impure. Preliminary studies in rats indicate that the soy product is at least as effective as that of bovine origin.
However, later clinical trials in humans found that "a daily supplement of S-PS (soybean derived PS) does not affect memory or other cognitive functions in older individuals with memory complaints."
On May 13, 2003, the U.S. Food and Drug Administration
Food and Drug Administration
The Food and Drug Administration is an agency of the United States Department of Health and Human Services, one of the United States federal executive departments...
stated "based on its evaluation of the totality of the publicly available scientific evidence, the agency concludes that there is not significant scientific agreement among qualified experts that a relationship exists between phosphatidylserine and reduced risk of dementia or cognitive dysfunction." FDA also stated "of the 10 intervention studies that formed the basis of FDA's evaluation, all were seriously flawed or limited in their reliability in one or more ways." It concludes that "most of the evidence does not support a relationship between phosphatidylserine and reduced risk of dementia or cognitive dysfunction, and that the evidence that does support such a relationship is very limited and preliminary." FDA did, however give "qualified health claim" status to phosphatidylserine, stating that, "Consumption of phosphatidylserine may reduce the risk of dementia in the elderly" and "Consumption of phosphatidylserine may reduce the risk of cognitive dysfunction in the elderly."
Sports nutrition
Phosphatidylserine has been demonstrated to speed up recovery, prevent muscle soreness, improve well-being, and might possess ergogenic properties in athletes involved in cycling, weight training and endurance running. Soy-PS, in a dose dependent manner (400 mg), has been reported to be an effective supplement for combating exercise-induced stress by blunting the exercise-induced increase in cortisolCortisol
Cortisol is a steroid hormone, more specifically a glucocorticoid, produced by the adrenal gland. It is released in response to stress and a low level of blood glucocorticoids. Its primary functions are to increase blood sugar through gluconeogenesis; suppress the immune system; and aid in fat,...
levels. PS supplementation promotes a desirable hormonal balance for athletes and might attenuate the physiological deterioration that accompanies overtraining and/or overstretching. In recent studies, PS has been shown to enhance mood in a cohort of young people during mental stress and to improve accuracy during tee-off by increasing the stress resistance of golf
Golf
Golf is a precision club and ball sport, in which competing players use many types of clubs to hit balls into a series of holes on a golf course using the fewest number of strokes....
ers.
Attention-deficit hyperactivity disorder
First pilot studies indicate that PS supplementation might be beneficial for children with attention-deficit hyperactivity disorderAttention-deficit hyperactivity disorder
Attention deficit hyperactivity disorder is a developmental disorder. It is primarily characterized by "the co-existence of attentional problems and hyperactivity, with each behavior occurring infrequently alone" and symptoms starting before seven years of age.ADHD is the most commonly studied and...
.
Safety
Traditionally, PS supplements were derived from bovine cortex (BC-PS); however, due to the potential transfer of infectious diseases, soy-derived PS (S-PS) has been established as a potential safe alternative. Soy-derived PS is Generally Recognized As Safe (GRASGras
Gras is a commune in the Ardèche department in southern France.-Population:-References:*...
) and is a safe nutritional supplement for older persons if taken up to a dosage of 200 mg three times daily. Phosphatidylserine has been shown to reduce specific immune response
Adaptive immune system
The adaptive immune system is composed of highly specialized, systemic cells and processes that eliminate or prevent pathogenic growth. Thought to have arisen in the first jawed vertebrates, the adaptive or "specific" immune system is activated by the “non-specific” and evolutionarily older innate...
in mice
MICE
-Fiction:*Mice , alien species in The Hitchhiker's Guide to the Galaxy*The Mice -Acronyms:* "Meetings, Incentives, Conferencing, Exhibitions", facilities terminology for events...
.
Dietary sources
PS can be found in meat, but is most abundant in the brain and in innards such as liver and kidney. Only small amounts of PS can be found in dairy products or in vegetables, with the exception of white beans.Table 1. PS content in different foods.
| Food | PS Content in mg/100 g |
|---|---|
| Bovine brain | 713 |
| Atlantic mackerel Atlantic mackerel The Atlantic mackerel , is a pelagic schooling species of mackerel found on both sides of the North Atlantic Ocean. The species is also called Boston mackerel, or just mackerel.... |
480 |
| Chicken Chicken The chicken is a domesticated fowl, a subspecies of the Red Junglefowl. As one of the most common and widespread domestic animals, and with a population of more than 24 billion in 2003, there are more chickens in the world than any other species of bird... heart |
414 |
| Atlantic herring Atlantic herring Atlantic herring is a fish in the family Clupeidae. It is one of the most abundant fish species on earth. Herring can be found on both sides of the Atlantic Ocean, congregating in large schools. They can grow up to in length and weigh more than... |
360 |
| Eel Eel Eels are an order of fish, which consists of four suborders, 20 families, 111 genera and approximately 800 species. Most eels are predators... |
335 |
| Offal Offal Offal , also called, especially in the United States, variety meats or organ meats, refers to the internal organs and entrails of a butchered animal. The word does not refer to a particular list of edible organs, which varies by culture and region, but includes most internal organs other than... (average value) |
305 |
| Pig Pig A pig is any of the animals in the genus Sus, within the Suidae family of even-toed ungulates. Pigs include the domestic pig, its ancestor the wild boar, and several other wild relatives... 's spleen Spleen The spleen is an organ found in virtually all vertebrate animals with important roles in regard to red blood cells and the immune system. In humans, it is located in the left upper quadrant of the abdomen. It removes old red blood cells and holds a reserve of blood in case of hemorrhagic shock... |
239 |
| Pig's kidney Kidney The kidneys, organs with several functions, serve essential regulatory roles in most animals, including vertebrates and some invertebrates. They are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and... |
218 |
| Tuna Tuna Tuna is a salt water fish from the family Scombridae, mostly in the genus Thunnus. Tuna are fast swimmers, and some species are capable of speeds of . Unlike most fish, which have white flesh, the muscle tissue of tuna ranges from pink to dark red. The red coloration derives from myoglobin, an... |
194 |
| Chicken leg, with skin, without bone | 134 |
| Chicken liver | 123 |
| White beans | 107 |
| Soft-shell clam Soft-shell clam Soft-shell clams, scientific name Mya arenaria, popularly called "steamers", "softshells", "longnecks", "piss clams", "Ipswich clams", or "Essex clams" are a species of edible saltwater clam, a marine bivalve mollusk in the family Myidae.... |
87 |
| Chicken breast, with skin | 85 |
| Mullet Mullet (fish) The mullets or grey mullets are a family and order of ray-finned fish found worldwide in coastal temperate and tropical waters, and in some species in fresh water. Mullets have served as an important source of food in Mediterranean Europe since Roman times... |
76 |
| Veal Veal Veal is the meat of young cattle , as opposed to meat from older cattle. Though veal can be produced from a calf of either sex and any breed, most veal comes from male calves of dairy cattle breeds... |
72 |
| Beef Beef Beef is the culinary name for meat from bovines, especially domestic cattle. Beef can be harvested from cows, bulls, heifers or steers. It is one of the principal meats used in the cuisine of the Middle East , Australia, Argentina, Brazil, Europe and the United States, and is also important in... |
69 |
| Pork Pork Pork is the culinary name for meat from the domestic pig , which is eaten in many countries. It is one of the most commonly consumed meats worldwide, with evidence of pig husbandry dating back to 5000 BC.... |
57 |
| Pig's liver Liver The liver is a vital organ present in vertebrates and some other animals. It has a wide range of functions, including detoxification, protein synthesis, and production of biochemicals necessary for digestion... |
50 |
| Turkey Turkey Turkey , known officially as the Republic of Turkey , is a Eurasian country located in Western Asia and in East Thrace in Southeastern Europe... leg, without skin or bone |
50 |
| Turkey breast without skin | 45 |
| Crayfish Crayfish Crayfish, crawfish, or crawdads – members of the superfamilies Astacoidea and Parastacoidea – are freshwater crustaceans resembling small lobsters, to which they are related... |
40 |
| Cuttlefish Cuttlefish Cuttlefish are marine animals of the order Sepiida. They belong to the class Cephalopoda . Despite their name, cuttlefish are not fish but molluscs.... |
31 |
| Atlantic cod Atlantic cod The Atlantic cod, Gadus morhua, is a well-known demersal food fish belonging to the family Gadidae. It is also commercially known as cod, codling or haberdine.... |
28 |
| Anchovy Anchovy Anchovies are a family of small, common salt-water forage fish. There are 144 species in 17 genera, found in the Atlantic, Indian, and Pacific Oceans. Anchovies are usually classified as an oily fish.-Description:... |
25 |
| Whole grain Whole grain Whole grains are cereal grains that contain cereal germ, endosperm, and bran, in contrast to refined grains, which retain only the endosperm. Whole grains can generally be sprouted while refined grains generally will not sprout. Whole-meal products are made by grinding whole grains in order to make... barley Barley Barley is a major cereal grain, a member of the grass family. It serves as a major animal fodder, as a base malt for beer and certain distilled beverages, and as a component of various health foods... |
20 |
| European hake Hake The term hake refers to fish in either of:* family Phycidae of the northern oceans* family Merlucciidae of the southern oceans-Hake fish:... |
17 |
| European pilchard (sardine) Sardine Sardines, or pilchards, are several types of small, oily fish related to herrings, family Clupeidae. Sardines are named after the Mediterranean island of Sardinia, around which they were once abundant.... |
16 |
| Trout Trout Trout is the name for a number of species of freshwater and saltwater fish belonging to the Salmoninae subfamily of the family Salmonidae. Salmon belong to the same family as trout. Most salmon species spend almost all their lives in salt water... |
14 |
| Soy lecithin | 10-20 |
| Rice Rice Rice is the seed of the monocot plants Oryza sativa or Oryza glaberrima . As a cereal grain, it is the most important staple food for a large part of the world's human population, especially in East Asia, Southeast Asia, South Asia, the Middle East, and the West Indies... (unpolished) |
3 |
| Carrot Carrot The carrot is a root vegetable, usually orange in colour, though purple, red, white, and yellow varieties exist. It has a crisp texture when fresh... |
2 |
| Ewe Domestic sheep Sheep are quadrupedal, ruminant mammals typically kept as livestock. Like all ruminants, sheep are members of the order Artiodactyla, the even-toed ungulates. Although the name "sheep" applies to many species in the genus Ovis, in everyday usage it almost always refers to Ovis aries... 's Milk Milk Milk is a white liquid produced by the mammary glands of mammals. It is the primary source of nutrition for young mammals before they are able to digest other types of food. Early-lactation milk contains colostrum, which carries the mother's antibodies to the baby and can reduce the risk of many... |
2 |
| Cow's Milk (whole, 3.5% fat) | 1 |
| Potato Potato The potato is a starchy, tuberous crop from the perennial Solanum tuberosum of the Solanaceae family . The word potato may refer to the plant itself as well as the edible tuber. In the region of the Andes, there are some other closely related cultivated potato species... |
1 |
The average daily PS intake from the diet in Western countries is estimated to be 130 mg.
Research
Annexin-A5 is a naturally-occurring protein with avid binding affinity for PS. Labeled-annexin-A5 enables visualization of cells in the early- to mid-apoptotic state in vitroIn vitro
In vitro refers to studies in experimental biology that are conducted using components of an organism that have been isolated from their usual biological context in order to permit a more detailed or more convenient analysis than can be done with whole organisms. Colloquially, these experiments...
or in vivo
In vivo
In vivo is experimentation using a whole, living organism as opposed to a partial or dead organism, or an in vitro controlled environment. Animal testing and clinical trials are two forms of in vivo research...
. Another PS binding protein is Mfge8
MFGE8
Milk fat globule-EGF factor 8 protein Mfge8), also known as lactadherin, is a protein which in humans is encoded by the MFGE8 gene.- Species distribution :Mfge8 is secreted protein found in vertebrates, including mammals as well as birds....
.
Tumors
TechnetiumTechnetium
Technetium is the chemical element with atomic number 43 and symbol Tc. It is the lowest atomic number element without any stable isotopes; every form of it is radioactive. Nearly all technetium is produced synthetically and only minute amounts are found in nature...
-labeled annexin-A5 enables distinction between malignant and benign tumours whose pathology includes a high rate of cell division and apoptosis in malignant compared with a low rate of apoptosis in benign tumors.