Nerve growth factor serum levels in treatment-resistant schizophrenic patients following electroconvulsive therapy

Background Electroconvulsive Therapy (ECT) has been widely applied to treat schizophrenia (SCZ) in the presence of resistance to pharmacotherapy. The mechanism of action of ECT in schizophrenia has not been fully clarified, though its intrinsic mechanism presents analogies with some neurobiological processes mediated by nerve growth factor (NGF). Objectives. The aim of this study was to investigate in patients with treatment-resistant schizophrenia (TRS) the effect of ECT on acute and long-term NGF serum levels and the association with the clinical outcomes. Methods. Twelve male inpatients with TRS underwent eight sessions of ECT. Blood samples were collected during the first and the eighth ECT at the following time points: 5 minutes before the induction of seizure and then at 0, 5, 15 and 30 minutes after seizure. Results. Following ECT treatment, a substantial clinical improvement in symptom severity was indicated by a significant reduction in the Positive and Negative Syndrome Scale (PANSS) total and subscales scores. Even though the baseline NGF levels showed an increase over time, there were no statistical differences in NGF at time 0 at the first and the eighth ECT session. Furthermore, no correlation was observed between the severity of schizophrenic symptoms and NGF levels. Conclusions. This is the first study addressing peripheral NGF during ECT treatment in TRS, as well as the first study in which NGF has been evaluated in different ECT sessions at various time points. These findings may potentiate the knowledge about the neurotrophic effects of ECT and the role of NGF in synaptic plasticity related to possible mechanisms of schizophrenia treatment. C