Plasma levels of IL-1Ra is associated with schizophrenia.

AIM: Although peripheral low-grade inflammation and brain-derived neurotrophic factor (BDNF) levels have been implicated in schizophrenia, the interactions between them remains to be fully revealed. We aimed to compare BDNF and cytokines in patients with schizophrenia and healthy controls. Additionally, we aim to investigate the association between peripheral levels of cytokines and BDNF in patients with schizophrenia.

METHODS: Plasma levels of BDNF, interferon-γ (IFN-γ), interleukin-10 (IL-10), IL-12, IL-1, IL-6, IL-8, tumor necrosis factor-α (TNF-α), macrophage migration inhibitory (MIF), IL-1 receptor antagonist (IL-1Ra) and CD40 Ligand (CD40 L) were compared in 45 schizophrenia patients and 38 healthy controls by Luminex technology.

RESULTS: Compared to the controls, the patients had significantly higher IL-1Ra levels (p = 0.031). We found a strong positive association between BDNF and CD40 L in patient group (rho = 0.858, p <0.001) as well as in control group (rho = 0.822, p <0.001) respectively. Furthermore, there was a negative association between BDNF and TNF-α in patients (rho = -0.429, p = 0.030) as well as in controls (rho = -0.649, p < 0.001).

CONCLUSION: These results suggested that the cytokine IL-1Ra may play a role in schizophrenia pathophysiology. Additionally, the interaction between cytokines and BDNF levels further indicated the diverse actions of these cytokines. This article is protected by copyright. All rights reserved.