Increased PLA2 activity in the hippocampus of patients with temporal lobe epilepsy and psychosis

Objective: The aim of this work was to investigate whether increased activity of the enzyme phospholipase A(2) (PLA(2)) in the brain, as frequently reported in schizophrenia, is also related to psychosis in epilepsy. Our working hypothesis was based on the increased prevalence of schizophrenia-like psychosis in patients with temporal lobe epilepsy (TLE) secondary to mesial temporal sclerosis (MTS), as compared to patients with other forms of epilepsy.

Methods: We determined PLA(2) activity in hippocampal tissue from 7 patients with TLE-MTS and psychosis, as compared to 9 TLE-MTS patients without psychosis. Hippocampal tissue was obtained from patients who underwent an anterior temporal lobectomy due to therapy-resistant epilepsy.

Results: We found that patients with TLE-MTS and psychosis had a significantly increased calcium-independent PLA(2) activity as compared to patients without psychosis (p = 0.016).

Conclusion: Our finding suggest that an increment in brain PLA(2) activity is not specific for schizophrenia, but rather may be associated to the manifestation of schizophrenia-like psychotic symptoms in general.