Association of TRPV1 and the SIRT3/SOD2 Signaling Pathway in Mononuclear Cells and Astrocyte-Derived Extracellular Vesicles in Patients with Schizophrenia.

OBJECTIVES: The transient receptor potential vanilloid type 1 (TRPV1) is a factor that mediates glial cell response with effects on mitochondrial function. It may affect the occurrence and development of schizophrenia. The aim of this study is to further explore schizophrenia biomarkers by analyzing TRPV1 and oxidative stress in astrocyte-derived extracellular vesicles (ADEs) and peripheral blood mononuclear cells (PBMCs). METHODS: A case-control study was conducted. The Positive and Negative Syndrome Scale and the Brief Assessment of Cognition in Schizophrenia (BACS) clinical data were obtained from 50 symptomatic patients with schizophrenia and 50 controls, and fasting peripheral blood samples were collected for the isolation of PBMCs and ADEs. Western blotting was used to assess TRPV1, Sirtuin3 (Sirt3), SOD2, and acetyl-SOD2. RESULTS: The patient group exhibited significantly reduced TRPV1 and Sirt3 expression levels in PBMCs and ADEs compared with the control group. In addition, there was a marked increase in SOD2 and acetyl-SOD2 levels. TRPV1 was negatively correlated with the negative symptom score in the patient PBMCs and ADEs. SOD2 showed positive correlations with the general psychopathology symptom score, and acetyl-SOD2 was positively correlated with the negative symptom score. The BACS total score was positively correlated with TRPV1 levels and negatively correlated with acetyl-SOD2 levels in the patient group. CONCLUSION: TRPV1 expressions in PBMCs and ADEs were reduced and closely correlated, and TRPV1 levels were associated with psychiatric symptoms and cognitive function in patients with schizophrenia. It was indicated that TRPV1 could be a biomarker for schizophrenia and reflect the disease severity.