Phosphatidylserine; Membrane Nutrient for Memory. A Clinical and Mechanistic Assessment

Working in the cell membrane milieu, phosphatidylserine (PS) is a nutrient that supports membrane proteins crucial for homeostasis, maintenance, and specialized cell functions. PS is found most concentrated in the brain, where its relative abundance reflects its involvement in specialized nerve cell functions such as chemical transmitter production and release, receptor action, and synaptic activity. The fundamental contributions of PS to the structure and function of individual nerve cells are expressed in the performance of the brain as a whole. More than 35 human studies that span almost 3 decades, together with numerous animal studies, indicate PS supports EEG integration, the HPAA (hypothalamic-pituitary-adrenal axis), and circadian rhythms of hormone release. Some sixteen clinical trials indicate that PS benefits measurable cognitive functions which tend to decline with age; these include memory, learning, vocabulary skills and concentration, as well as mood, alertness, and sociability. PS is a phospholipid, ubiquitous in membranes and obligatory for all the cells of the body. Present in common foods in small amounts, PS may be a semi-essential nutrient. Although it can be synthesized in vivo from precursors, its multistep biosynthesis is energetically costly. Until recently, supplemental PS was available only from bovine brain. Now PS is available as a soy lecithin-based concentrate. With its proven benefits against agerelated mental decline, phosphatidylserine might represent a truly safe and effective means for improving the quality of life of the elderly. (Alt Med Rev 1996;1(2):70-84) The progressive loss of mental agility with age has become a major focus of basic and clinical research efforts. Beginning around midlife, the brain’s higher functions of memory, learning, semantic manipulation, and concentration (collectively referred to as cognition) measurably begin to fade. The ancient writer Virgil put it best in 70 B.C.: “Age takes away all things, even the mind.” An impressive body of human studies with PS, published over a span of almost 3 decades, now makes possible an optimistic approach to conserving those brain functions that decline with age.