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Classical pathway complement activity in schizophrenia

Svetlana Hakobyan1, Anna Boyajyan, Robert B Sim

  • 1Institute of Molecular Biology NAS RA, 7 Hasratyan St, 375014 Yerevan, Armenia.

Neuroscience Letters
|January 6, 2005
PubMed

Insights

Schizophrenia pathogenesis may involve complement system alterations. Specifically, complement components C1, C3, and C4 showed higher activity, while C2 activity was lower in patients compared to healthy individuals.

Area of Science:

  • Neuroimmunology
  • Complement System Biology

Background:

  • The role of the complement system in schizophrenia pathogenesis is suggested but conflicting.
  • Classical pathway complement activity data in schizophrenia patients are inconsistent.

Purpose of the Study:

  • To investigate the hemolytic activities of complement and its classical pathway components (C1, C2, C3, C4) in schizophrenia patients.
  • To compare complement activity between schizophrenia patients with a positive family history and healthy controls.

Main Methods:

  • Serum samples from schizophrenia patients and healthy subjects were analyzed.
  • Total hemolytic complement activity and individual component activities (C1, C2, C3, C4) were measured.

Main Results:

  • Significantly higher hemolytic activity for complement components C1, C3, and C4 in schizophrenia patients compared to controls.
  • Significantly lower hemolytic activity for complement component C2 in schizophrenia patients.
  • No significant difference in total hemolytic complement activity between patient and control groups.
  • C3 hemolytic activity was 2.17 times higher in medicated patients than in drug-free patients.

Conclusions:

  • Schizophrenia pathogenesis is associated with altered activities of classical pathway complement components.
  • Specific complement component dysregulation, not total activity, may be relevant in schizophrenia.

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