The plasma levels of interleukin-12 in schizophrenia, major depression, and bipolar mania: Effects of psychotropic drugs

Yong Ku Kim, I. B. Suh, H. Kim, Changsu Han, C. S. Lim, S. H. Choi, J. Licinio

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170 Citations (Scopus)


Interleukin-12 (IL-12) plays a key role in promoting T helper 1 (Th1) responses and subsequent cell-mediated immunity. Given the role of cytokines in the pathogenesis of psychiatric disorders, the dysregulation of IL-12 in these illnesses would be expected. We measured the plasma levels of IL-12 in 102 psychiatric patients (43 schizophrenia, 34 major depression and 25 bipolar disorder) and 85 normal controls. In addition, IL-12 levels of the patients were measured after an 8-week treatment to assess whether the levels were affected by medication. The IL-12 levels of the patient group with major depression were significantly higher than that of the control group, whereas no differences were found among the other groups. IL-12 values of the three patient groups decreased significantly after 8 weeks of treatment. These findings support the hypothesis that activation of the inflammatory response system and in particular of Th-1-like cells, is involved in the pathophysiology of major depression and that repeated administration of antidepressive and antipsychotic drugs may suppress IL-12 plasma concentrations in psychiatric patients.

Original languageEnglish
Pages (from-to)1107-1114
Number of pages8
JournalMolecular Psychiatry
Issue number10
Publication statusPublished - 2002 Dec 1



  • Cytokine
  • Inflammatory response system
  • Interleukin-12
  • Major depression
  • Mania
  • Schizophrenia

ASJC Scopus subject areas

  • Molecular Biology
  • Cellular and Molecular Neuroscience
  • Psychiatry and Mental health

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