Phosphatidylserine

Phosphatidylserine
Identifiers
CAS number	8002-43-5
PubChem	445141
Properties
Molecular formula	C13H24NO10P
Molar mass	385.304
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Phosphatidylserine (abbreviated Ptd-L-Ser or PS) 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 apoptotic cell death phosphatidylserine is no longer restricted to the cytosolic part of the membrane, but becomes exposed on the surface of the cell.

Health benefits

Memory and cognition

Early studies of phosphatidylserine distilled the chemical from bovine brain. Because of concerns about Bovine Spongiform Encephalopathy, however, modern studies and commercially available products are made from soybeans. The fatty acids attached to the serine in the soy product are not identical to those in the bovine product, which is also impure. However, preliminary studies indicate that the soy product is at least as effective as that of bovine origin. ^[1][2]

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 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 cortisol levels.^[3] PS supplementation promotes a desirable hormonal balance for athletes and might attenuate the physiological deterioration that accompanies overtraining and/or overstretching.^[4] 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 golfers.^[5]

Attention-deficit hyperactivity disorder

First pilot studies indicate that PS supplementation might be beneficial for children with attention-deficit hyperactivity disorder.^[6][7]

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 safe alternative. Soy-derived PS is Generally Recognized As Safe (GRAS) and is a safe nutritional supplement for older persons if taken up to a dosage of 200 mg three times daily. ^[8] Phosphatidylserine has been shown to reduce specific immune response in mice. ^[9][10]

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.^[11]

The average daily PS intake from the diet in Western countries is estimated to be 130 mg.

Applications

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 vitro or in vivo. Another PS binding protein is Mfge8.

Tumors

Technetium-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.

References

External links

• DrugBank info page
• FDA Qualified Health Claim Phosphatidylserine and Cognitive Dysfunction and Dementia
• MeSH Phosphatidylserines