Phosphatidylserine

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Phosphatidylserine
Phosphatidyl-Serine.png
Identifiers
CAS number 8002-43-5 YesY
PubChem 6323481
ChemSpider 13628254 YesY
DrugBank DB00144
ChEBI CHEBI:18303 YesY
Jmol-3D images Image 1
Properties
Molecular formula C13H24NO10P
Molar mass 385.304
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 YesY (verify) (what is: YesY/N?)
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 apoptosis, phosphatidylserine is no longer restricted to the cytosolic part of the membrane, but becomes exposed on the surface of the cell.[1]

Possible health benefits[edit]

Memory and cognition[edit]

Early studies of phosphatidylserine distilled the chemical from bovine brain. Commercially available products are made from cabbage or soybeans, because of concerns about mad cow disease.[2] The fatty acids attached to the serine in the plant-based products have a similar, but not identical, chemical structure,[3] but without the risk of infection.

Although a preliminary study in rats indicated that the soy product was as effective as that of bovine origin in one of three behavioral tests,[4][5] 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."[6]

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 gave "qualified health claim" status to phosphatidylserine, allowing labels 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," with the disclaimer that, "Very limited and preliminary scientific research suggests that phosphatidylserine may reduce the risk of cognitive dysfunction in the elderly. FDA concludes that there is little scientific evidence supporting this claim."[3]

Sports nutrition[edit]

In athletes, PS has been shown to improve performance,[7][8][9] endocrine response to exercise stress,[10][11] and decreased muscle damage[12] in athletes involved in cycling, weight training, golf and endurance running. PS has been reported to be an effective supplement for combating exercise-induced stress by blunting the exercise-induced increase in cortisol levels in a dose dependent manner.[10][11] PS supplementation promotes a desirable hormonal balance for athletes and might attenuate the physiological deterioration that accompanies overtraining and/or overstretching.[10] In recent studies, PS has been shown to enhance mood in a cohort of young people during mental stress[13] and to improve accuracy during tee-off by increasing the stress resistance of golfers.[9]

Attention-deficit hyperactivity disorder[edit]

First pilot studies indicate that PS supplementation might be beneficial for children with attention-deficit hyperactivity disorder.[14][15]

A follow-up study backed up previous findings. The study found children supplementing with 200 mg PS per day for two months saw a significant improvement in ADHD symptoms.[16]

Safety[edit]

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 (GRAS) and is a safe nutritional supplement for older persons if taken up to a dosage of 200 mg three times daily.[17]

Dietary sources[edit]

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.

Biosynthesis of Phosphatidylserine

Table 1. PS content in different foods.[18]

Food PS Content in mg/100 g
Soy lecithin 5900 [19]
Bovine brain 713
Atlantic mackerel 480
Chicken heart 414
Atlantic herring 360
Eel 335
Offal (average value) 305
Pig's spleen 239
Pig's kidney 218
Tuna 194
Chicken leg, with skin, without bone 134
Chicken liver 123
White beans 107
Soft-shell clam 87
Chicken breast, with skin 85
Mullet 76
Veal 72
Beef 69
Pork 57
Pig's liver 50
Turkey leg, without skin or bone 50
Turkey breast without skin 45
Crayfish 40
Cuttlefish 31
Atlantic cod 28
Anchovy 25
Whole grain barley 20
European hake 17
European pilchard (sardine) 16
Trout 14
Rice (unpolished) 3
Carrot 2
Ewe's Milk 2
Cow's Milk (whole, 3.5% fat) 1
Potato 1

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

Metabolism[edit]

Phosphatidylserine is biosynthesized in bacteria by condensing the amino acid serine with CDP (cytidine diphosphate)-activated phosphatidic acid.[20] In mammals, phosphatidylserine is produced by base-exchange reactions with phosphatidylcholine and phosphatidylethanolamine. Conversely, phosphatidylserine can also give rise to phosphatidylethanolamine and phosphatidylcholine, although in animals the pathway to generate phosphatidylcholine from phosphatidylserine only operates in the liver.[21]

Applications[edit]

Research[edit]

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[edit]

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[edit]

  1. ^ Verhoven, B; Schlegel, RA, Williamson, P (1995-11-01). "Mechanisms of phosphatidylserine exposure, a phagocyte recognition signal, on apoptotic T lymphocytes". The Journal of experimental medicine 182 (5): 1597–601. doi:10.1084/jem.182.5.1597. PMC 2192221. PMID 7595231. 
  2. ^ "Can phosphatidylserine improve memory and cognitive function in people with Alzheimer's disease?". mayoclinic.com. Retrieved 2013-03-17. 
  3. ^ a b Christine L. Taylor, Ph.D. (May 13, 2003). "Phosphatidylserine and Cognitive Dysfunction and Dementia (Qualified Health Claim: Final Decision Letter)". Office of Nutritional Products, Labeling and Dietary Supplements Center for Food Safety and Applied Nutrition, U.S. Food and Drug Administration. Retrieved 2014-01-20. 
  4. ^ Blokland A, Honig W, Brouns F, Jolles J (October 1999). "Cognition-enhancing properties of subchronic phosphatidylserine (PS) treatment in middle-aged rats: comparison of bovine cortex PS with egg PS and soybean PS". Nutrition 15 (10): 778–83. doi:10.1016/S0899-9007(99)00157-4. PMID 10501292. 
  5. ^ Crook, T. H.; R. M. Klatz (ed) (1998). Treatment of Age-Related Cognitive Decline: Effects of Phosphatidylserine in Anti-Aging Medical Therapeutics 2. Chicago: Health Quest Publications. pp. 20–29. 
  6. ^ Jorissen BL, Brouns F, Van Boxtel MP, Ponds RW, Verhey FR, Jolles J, Riedel WJ. (2001). "The influence of soy-derived phosphatidylserine on cognition in age-associated memory impairment". Nutritional Neuroscience 4 (2): 121–34. PMID 11842880. 
  7. ^ Kingsley M, Wadsworth D, Kilduff LP, McEneny J, Benton D (August 2005). "Effects of phosphatidylserine on oxidative stress following intermittent running". Med Sci Sports Exerc 37 (8): 1300–1306. PMID 16118575. 
  8. ^ Kingsley MI, Miller M, Kilduff LP, McEneny J, Benton D (January 2006). "Effects of phosphatidylserine on exercise capacity during cycling in active males". Med Sci Sports Exerc 38 (1): 64–71. PMID 16394955. 
  9. ^ a b Jäger R, Purpura M, Geiss K-R, Weiß M, Baumeister J, Amatulli F, Schröder L, Herwegen H (December 2007). "The effect of phosphatidylserine on golf performance". International Society of Sports Nutrition 4 (1). 
  10. ^ a b c Starks MA, Starks SL, Kingsley M, Purpura M, Jäger R (July 2008). "The effects of phosphatidylserine on endocrine response to moderate intensity exercise". J Int Soc Sports Nutr 5. PMC 2503954. 
  11. ^ a b Monteleone P, Maj M, Beinat L, Natale M, Kemali D (1992). "Blunting by chronic phosphatidylserine administration of the stress-induced activation of the hypothalamo-pituitary-adrenal axis in healthy men". Eur J Clin Pharmacol 42 (4): 385–388. PMID 1325348. 
  12. ^ Fernholz KM, Seifert JG, Bacharach DW, Burke ER, Gazal O (2000). "The Effects of Phosphatidyl Serine on Markers of Muscular Stress in Endurance Runners [abstract]". Med Sci Sports Exerc 32 (4): S321. 
  13. ^ Benton D, Donohoe RT, Sillance B, Nabb S (2001). "The Influence of phosphatidylserine supplementation on mood and heart rate when faced with an acute stressor". Nutr Neurosci 4 (3): 169–178. PMID 11842886. 
  14. ^ Hirayama S, Masuda Y, Rabeler R (September–October 2006). "Effect of phosphatidylserine administration on symptoms of attention-deficit/hyperactivity disorder in children". Agro Food 17 (5): 32–36. 
  15. ^ Vaisman N, Kaysar N, Zaruk-Adasha Y, Pelled D, Brichon G, Zwingelstein G, Bodennec J (2008). "Correlation between changes in blood fatty acid composition and visual sustained attention performance in children with inattention: effect of dietary n-3 fatty acids containing phospholipids". The American Journal of Clinical Nutrition 87 (5): 1170–1180. PMID 18469236. 
  16. ^ Hirayama S., Terasawa K., Rabeler R., Hirayama T., Inoue T., Tatsumi Y., Purpura M. & Jäger R. (2013). "The effect of phosphatidylserine administration on memory and symptoms of attention-deficit hyperactivity disorder: a randomised, double-blind, placebo-controlled clinical trial". Human Nutrition and Dietetics. doi:10.1111/jhn.12090. PMID 23495677. 
  17. ^ Jorissen BL, Brouns F, Van Boxtel MP, Riedel WJ (October 2002). "Safety of soy-derived phosphatidylserine in elderly people". Nutr Neurosci 5 (5): 337–343. doi:10.1080/1028415021000033802. PMID 12385596. 
  18. ^ Souci SW, Fachmann E, Kraut H (2008). Food Composition and Nutrition Tables. Medpharm Scientific Publishers Stuttgart. 
  19. ^ C.R. Scholfield (October 1981). "Composition of Soybean Lecithin". Journal of the American Oil Chemists' Society 58 (10): 890. 
  20. ^ Phosphatidylserine and related lipids
  21. ^ "Phosphatidylcholine, structure, occurrence, biochemistry and analysis". Lipidlibrary.aocs.org. 2012-04-30. Retrieved 2012-08-06. 

External links[edit]