The Relationship between Treatment Response in Patients with Acute Psychotic Episodes of Schizophrenia and the Activity of Their Platelet Enzymes

Abstract

Background: imbalance in the energy processes, such as oxidative phosphorylation intensity, and antioxidant systems, and impaired glutamate metabolism in the brain are important biochemical pathogenetic links in the development of schizophrenia. Changes in the activity of a number of platelet enzymes involved in these biochemical pathways were found in patients with schizophrenia.Aim: to assess the relationship between the treatment effciency of acute psychotic episode in patients with paranoid schizophrenia and the activity levels of platelet enzymes involved in energy metabolism (cytochrome c-oxidase, COX), in the antioxidant glutathione system (glutathione reductase, GR), and glutamate metabolism (glutamate dehydrogenase, GDH).Patients and methods: we examined hospitalized adult patients with a diagnosis of paranoid schizophrenia, episodic course, exacerbation of the disease (F20.01), receiving antipsychotic therapy, and healthy volunteers as a control group for assessment of control ranges for enzymatic activities. Psychometric assessment was carried out using the Positive and Negative Syndrome Scale (PANSS). Treatment response was assessed as good with a reduction in PANSS scores of 20% or more. The evaluation was performed on the first days after hospitalization and immediately before discharge.Results: 113 subjects were recruited. 50 healthy volunteers formed the control group and 63 patients, including 60 men and 3 women made up the study group. All indicators were obtained in all control group members and in 42 patients. In the group with a good treatment response, the baseline COX, GDH and GR activities proved to be significantly more often met within the control range, and the GR activity in half of the patients increased after the treatment course. In the group with insuffcient response, half of the patients had an increase in GDH activity after treatment. Of all the biochemical indices, the parameter most associated with therapeutic response was GDH activity.Conclusion: GDH activity can be considered as a possible candidate for predicting the therapeutic response to antipsychotic therapy.