Correlation between platelet and brain PLA2 activity

The phospholipase A2 (PLA2) enzymes have been implicated in several neuropsychiatry disorders and activity alterations have been described in brain and platelet. Since brain tissue is not readily available for the measurement of PLA2 activity, it would be of interest to test directly whether PLA2 activities in both tissues are correlated. We performed this task assessing PLA2 activity in platelets and hippocampus collected simultaneously from 19 patients undergoing temporal lobectomy for treatment of refractory epilepsy. Our findings suggest that total PLA2 activity in platelets may reflect the total activity of the enzyme in the brain (rs=0.59, p=0.008). However in our sample no correlations were found between the subgroups of the enzyme in brain and in platelets. This lack of correlations may be due to different effects of drug treatment on the PLA2 subtypes. In face of the difficulty to obtain brain tissues from living patients, further studies with larger drug-free samples are warranted to clarify whether the use of platelets is a reliable strategy to reflect the subtypes of PLA2 activity in the brain.