Elevated levels of circulating IL-18BP and perturbed regulation of IL-18 in schizophrenia

Journal of Neuroinflammation

Paola Bossù¹  Gianfranco Spalletta²  Sabrina Fagioli²  Carlo Caltagirone³  Ivo Alex Rubino³  Antonio Ciaramella²  Francesca Salani²  Ilaria Palladino² 

[1] Department of Clinical and Behavioral Neurology, Experimental Neuro-psychobiology Lab, IRCCS Santa Lucia Foundation, Via Ardeatina, 306, I-00179, Rome, Italy;Clinical and Behavioral Neurology, IRCCS Fondazione Santa Lucia, Via Ardeatina 306, 00179, Rome, Italy;Department of Neuroscience, University Tor Vergata, Via Montpellier 1, 00133, Rome, Italy

关键词: Schizophrenia;    Inflammation;    Interleukin-18 Binding Protein;    Interleukin-18;   

Others  :  1160277
DOI  :  10.1186/1742-2094-9-206

 received in 2012-07-06, accepted in 2012-08-13,  发布年份 2012

【 摘 要 】

Background

The pleiotropic pro-inflammatory cytokine Interleukin (IL)-18 has been proposed to play a role in schizophrenia, since elevated circulating levels of its protein and altered frequencies of genetic variants in its molecular system are reported in schizophrenic patients.

Methods

We analyzed 77 patients with schizophrenia diagnosis (SCZ) and 77 healthy control subjects (HC) for serum concentration of both IL-18 and its natural inhibitor, the IL-18 binding protein (IL-18BP).

Results

We confirmed that serum levels of total IL-18 are significantly increased in SCZ, as compared to HC. However, due to a highly significant increase in levels of circulating IL-18BP in SCZ, as compared to HC, the levels of free, bioactive IL-18 are not significantly different between the two groups. In addition, the relationships between the levels of IL-18 and its inhibitor, as well as between the two molecules and age appear dissimilar for SCZ and HC. In particular, the elevated levels of IL-18BP, likely a consequence of the body’s attempt to counteract the early prominent inflammation which characterizes schizophrenia, are maintained in earlier and later stages of the disease. However, the IL-18BP elevation appears ineffective to balance the IL-18 system in younger SCZ patients, while in older patients the levels of circulating bioactive IL-18 are comparable to those of HC, if not lower.

Conclusions

In conclusion, these findings indicate that the IL-18 system is perturbed in schizophrenia, supporting the idea that this pro-inflammatory cytokine might be part of a pathway of genetic and environmental components for vulnerability to the disease.

【 授权许可】

   
2012 Palladino et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1 .

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