Oral administration of soybean lecithin transphosphatidylated phosphatidylserine improves memory impairment in aged rats

Soybean lecithin transphosphatidylated phosphatidylserine (SB-tPS) was prepared from soybean lecithin and L-serine by a transphosphatidylation reaction, and its effect on age-related memory impairment was evaluated in rats by the Morris water maze test. Continuous oral administration of SB-tPS (60 mg(.)kg(-1.)d(-1) for 60 d) to male aged rats (24-25 mo) significantly improved performance in the water maze escape test (P < 0.01 vs. control aged rats) similar to bovine brain cortex-derived phosphatidylserine, which restores cognitive function in patients with senile dementia. SB-tPS also increased acetylcholine release and the Na+, K+-ATPase activity of the synaptosomes prepared from these aged rats to the level in young rats. The nootropic actions of SB-tPS in the present study can be partly explained by the changes in these biochemical activities.