State-dependent alterations in mitochondrial complex I activity in platelets: a potential peripheral marker for...

Area of Science:

• Neuroscience
• Biochemistry
• Psychiatry

Background:

• Schizophrenia is a severe psychiatric disorder with heterogeneous symptoms, possibly linked to altered energy metabolism and mitochondrial dysfunction.
• Mitochondrial dysfunction, particularly in complex I, is implicated in schizophrenia's pathophysiology.

Purpose of the Study:

• To investigate mitochondrial complex I in platelets of schizophrenia patients across different disease states.
• To assess complex I's potential as a peripheral biomarker for schizophrenia.

Main Methods:

• Enzymatic activity, mRNA, and protein levels of mitochondrial complex I were analyzed in platelets from 113 schizophrenia patients and 37 controls.
• Methods included enzyme kinetics, RT-PCR, and Western blot analyses.

Main Results:

• Platelet complex I activity varied with schizophrenia disease state: increased in acute episodes, decreased in residual states.
• Activity positively correlated with positive symptom severity.
• Similar alterations observed in complex I subunit mRNA and protein levels.

Conclusions:

• Platelet mitochondrial complex I exhibits altered activity and expression in schizophrenia, correlating with clinical status.
• Mitochondrial complex I shows potential as a novel, reliable peripheral biomarker for schizophrenia diagnosis and monitoring.