Phosphatidyl serine is a phospholipid that is classified as a polar ionic compound Phosphatidyl serine is synthesized in the body primarily via exchange of ethanolamine, from phosphatidyl ethanolamine, for serine. Biosynthesis also requires adequate levels of folic acid, vitamin B12, and essential fatty acids.
Phosphatidyl serine is a vital component of cell membranes and is the major acidic phospholipid in the brain. Its fluid nature, which is necessary for cell to cell communication and cellular metabolism, underscores the importance of this compound in cell membrane function and integrity.
This phospholipid has broad effects in the central nervous system. Administering preparations of phosphatidyl serine to aged rats has increased dopamine release in the striatum, stimulated acetylcholine secretion, and has prevented age-related atrophy of cholinergic cells in the basal forebrain. Phosphatidyl serine supplementation has demonstrated changes in EEG activity in humans. Taking Phosphatidyl serine supplementation over a period of 30 days has restored the circadian rhythmicity of thyroid-stimulating hormone (TSH) secretion in hospitalized patients.
Soybean oil is the primary dietary source of phosphatidyl serine. Synthesis of this compound within the body requires an adequate supply of serine, which can be found in meats, soy, dairy products, wheat gluten, and peanuts. In order to obtain therapeutic levels of phosphatidyl serine, supplements are required. Preparations are derived either from bovine brain cortex or soybeans.
The main applications of phosphatidyl serine include the treatment of cognitive impairments, stress and depression.
Phosphatidyl serine supplementation has demonstrated positive effects on cognitive decline in elderly patients. A review published in 2003 summarized that most of the studies demonstrate a modest benefit of phosphatidyl serine on, specifically, word recall in elderly patients with cognitive decline; but only one study showed improvement in a variety of memory tests.
Alzheimer’s disease has also received interest in the phosphatidylserine research community, as memory is also impacted in this condition. An initial study of patients with probable Alzheimer’s disease examined the effect of bovine cortex phosphatidy serine versus placebo. Results showed improvement on several measures of cognitive ability, and was most pronounced in patients with less severe impairment. The authors concluded that this treatment would be most beneficial for patients with early stage Alzheimer’s disease.
An interesting application of phosphatidyl serine is in addressing stress. In a double- blind study of healthy men, phosphatidyl serine was administered to half of the participants10 minutes before starting exercise (physically induced stress). The treatment standard was set at administering 50 or 75 milligrams of bovine-cortex phosphatidyl serine (BC-PS) intravenously, or oral placebo. The results showed that pretreatment with both 50 and 75mg BC-PS significantly blunted the ACTH and cortisol responses to physical stress.
Another study examined the effect of an oral supplementation of BC-PS on physically induced stress. Healthy subjects took 800mg per day for 10 days. Again, BC-PS significantly blunted the ACTH and cortisol responses to physical exercise without affecting the rise in plasma growth hormone and prolactin. Plant derived phosphatidyl serine has also demonstrated positive effects on stress in humans
In patients with depressive disorders, supplementation with 300 milligrams daily of bovine-cortex phophatidyl serine for 30 days resulted in consistent improvement of depressive symptoms, memory and behavior.
Low levels of phosphatidyl serine are more common in the elderly. In order to synthesize this compound, an adequate supply of folic acid, vitamin B12, and essential fatty acids are necessary. If any of these levels are low, the brain may not be able to manufacture sufficient levels of phospahtidyl serine. Impaired mental function and depression are also associated with low phosphatidyl serine levels.
Phosphatidyl serine is generally considered a safe therapeutic agent. Bovine brain-cortex phosphatidylserine supplements have been consistently tolerated in humans at levels exceeding 300 milligrams daily.
Phosphatidyl serine derived from soybeans has demonstrated tolerability in elderly subjects at dosages of both 300 milligrams and 600 milligrams daily as well.
Moreover, standard biochemical and hematological safety parameters, blood pressure, heart rate, and adverse events were not affected as compared with placebo after 6 and 12 weeks of treatment.
Nausea may occur as an adverse effect in some patients. No teratogenicity or mutation has been observed in animal studies.