Cognitive training increases platelet PLA2 activity in healthy elderly subjects

Phospholipases A2 (PLA2) are ubiquitous enzymes involved in membrane fatty acid metabolism and intracellular signalling. Recent studies have shown that PLA2 subtypes are implicated in the modulation of pathways related to memory acquisition and retrieval. We investigated the effects of cognitive training on platelet PLA2 activity in healthy elderly individuals. Twenty-three cognitively unimpaired older adults were randomly assigned to receive memory training or standard outpatient care only. Both groups were cognitively assessed by the same protocol, and the experimental group (EG) underwent a four-session memory training intervention. Pre- and post-test measures included prose and list recall, WAIS-III digit symbol, strategy use measures and platelet PLA2 group activity. After cognitive training, patients in the EG group had significant increase in cytosolic, calcium-dependent PLA2 (cPLA2), extracellular (or secreted), calcium-dependent PLA2 (sPLA2), total platelet PLA2 activity, and significant decrease in platelet calcium-independent PLA2 (iPLA2) activity. Our results suggest that memory training may have a modulating effect in PLA2-mediated biological systems associated with cognitive functions and neurodegenerative diseases.