Platelet glutamate dehydrogenase activity and efficacy of antipsychotic therapy in patients with schizophrenia

Abstract

Summary Background Evaluation of possible relationship between platelet glutamate dehydrogenase (GDH) activity and mental state of schizophrenia patients after antipsychotic pharmacotherapy. Methods Patients (n = 50) with chronic paranoid schizophrenia (F20.0) initially in acute psychotic state were examined before and after a treatment course with antipsychotics. When assessing the patients’ states using PANSS, the »responder« category was attributed to those patients who had not less than 30% reduction in the score for the corresponding PANSS »subscale«. The control group (n = 48) was age- and gender-matched with the patient group. Platelet glutamate dehydrogenase (GDH) activity was measured in patients twice, before and after the treatment course, and once in controls. Results Significantly reduced GDH activity was found in patients compared with controls. The patient group was divided into two subgroups according to median GDH activity at baseline: above and below the median GDH, subgroup 1 and subgroup 2, respectively. GDH activity significantly increased from its level at baseline after antipsychotic treatment in subgroup 2. Distribution of non-responders / responders to antipsychotic treatment (by PANSS scores) was significantly uneven among subgroups 1 and 2. In subgroup 1, GDH activity levels significantly correlated with PANSS scores after the treatment course. Conclusions Baseline platelet GDH activity might serve as a predictor of antipsychotic therapy efficacy in schizophrenia patients.

Synergistic, long-term effects of glutamate dehydrogenase 1 deficiency and mild stress on cognitive function and mPFC gene and miRNA expression

“…This further supports the importance of glutamate homeostasis, maintained by a multitude of metabolic and synaptic components, in cognitive function. This is the rst demonstration of a gene x environment interaction in mice with abnormal expression of Glud1, which is downregulated in schizophrenia 20 and predicts antipsychotic treatment e cacy 70 . Similarly to other psychiatric disorders, schizophrenia symptoms are believed to be "triggered" by an external event in individuals with underlying genetic susceptibility 71 .…”

Advanced Biomarkers of Hepatotoxicity in Psychiatry: A Narrative Review and Recommendations for New Psychoactive Substances

“…The largest number of studies on the importance of GDH in psychiatry relate to schizophrenia. Savushkina et al found that baseline GDH levels could serve as a predictor of the efficacy of antipsychotic therapy in patients with schizophrenia, as in that study, GDH activity significantly increased during post-antipsychotic treatment [201]. According to Burbaev et al, treatment with olanzapine affects the amounts of glutamate-metabolising enzymes in the platelets of patients with chronic schizophrenia.…”

“…It was also found that the longer the disease lasted before starting the treatment cycle, the higher the GDH levels measured after treatment [202,203]. Baseline platelet GDH activity may serve as a predictor of the efficacy of antipsychotic therapy in patients with schizophrenia [201]. A review by Plaitakis on the topic of GDH deregulation in neurological diseases showed that GDH deregulation in schizophrenia remains an important issue to be addressed [204].…”

Биохимические Аспекты Применения Дополнительной Фармакотерапии При Лечении Психозов Позднего Возраста

“…Активность ГДГ определяли (только в тромбоцитах) по скорости снижения поглощения НАД•Н при 340 нм по методу Фишера [20] согласно ранее предложенным модификациям [21]. Активность ГР определяли по скорости окисления НАДФ•Н в реакции восстановления окисленного глутатиона [22].…”