Antipsychotics can modulate the cytokine profile in schizophrenia: Attenuation of the type-2 inflammatory response

Abstract

Objective: We recently reported that the type-2 cytokine response is increased in schizophrenia. The aim of this study was to analyse the effects of antipsychotic drugs on the serum levels of type-1 (TNF-α, IFN-γ), type-2 (IL-4, IL-10), type-17 (IL-17) and regulatory cytokines (TGF-β, IL-27 and IL-6). Methods: Cytokine measurements in the patients were performed on day 0 and day 30 of the treatment using standard ELISA assays. Three groups of subjects were studied: patients that were unmedicated with First Episode Psychosis (FEP; n = 88), patients that were treated with antipsychotics with Schizophrenia in relapse (SC in relapse; n = 45) and healthy controls (n = 36). Results: TGF-β levels were increased in both patient groups and were further enhanced after treatment in the FEP group (p= 0.014) but not in the SC relapse group. Antipsychotic treatment was correlated with lower levels of IL-4, IL-6 and IL-27 (p< 0.005) in the FEP group. Finally, the serum levels of IL-17 were not significantly altered between the two measurements but were significantly lower in the FEP group (p< 0.001) when compared with healthy controls. After therapy, patients with SC who were in relapse had decreased serum levels of IL-4 (p= 0.006) and IL-6 (p= 0.007). We also observed a weak negative correlation between the IFN-γ/TGF-β ratio and the total PANSS score and between the IL-17/TGF-β ratio and the negative and general psychopathology subscales. Conclusion: The increased type-2 cytokine serum levels in schizophrenia appear to be downregulated by antipsychotic treatment. © 2013 Elsevier B.V.