Over expression of MMP9 gene in peripheral blood of schizophrenic patients

Schizophrenia (SCZ) is a complex psychiatric disorder with one percent prevalence in world population and severs positive, negative and cognitive symptoms. Matrix metallopeptidase 9 (MMP-9) or gelatinase B (GELB) located in 20q11 belong to the zinc-metalloproteinases family which are involved in the degradation of the extracellular matrix. Previous studies were reported involvement of MMP9 over expression with etiology of multiple sclerosis and metastatic tumors.mRNA level of MMP9 gene have been studied in peripheral blood of 50 Iranian schizophrenic patients and 50 non-psychiatric subjects by using quantitative Real time PCR. Also positive and negative symptom scale (PANSS) from patients and Wechsler Adult Intelligence Scale (WAISE) from all subjects were obtained.Significant over expression of MMP9 was detected in SCZ vs. non-psychiatrics. Correlations were found between over expression of MMP9 and higher scores of positive symptoms in PANSS. No significant correlation was found between gene expression and WAISE results.Findings were suggested MMP9 involvement in etiology of schizophrenia. It seems that metalloproteinase deregulation may lead to neuronal dysfunction which in turn increases the positive symptoms in schizophrenic patients.