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

J Med Biochem. 2020 Jan 10;39(1):54-59. doi: 10.2478/jomb-2019-0018.

Abstract

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 ageand 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.

Uvod: Proučavan je mogući odnos između aktivnosti trombocitne glutamat dehodrogenaze (GDH) i mentalnog stanja pacijenata sa shizofrenijom nakon antipsihotične terapije.

Metode: Ispitivani su pacijenti (n = 50) sa hroničnom paranoidnom shizofrenijom (F20.0) inicijalno u akutnom psihotičnom stanju pre i nakon tretmana sa antipsihoticima. Kada je procenjivano stanje pacijenata primenom PANSS, "resoponder" kategorija je odgovarala onima koji su imali manje od 30% smanjenja u odnosu na odgovarajuću PANSS "subskalu". Kontrolnu grupu činilo je (n = 48) osoba sličnog pola i starosti. Aktivnost trombocitne glutamat dehidrogenaze (GDH) merena je kod pacijenata dva puta, pre i posle tretmana i jedanput kod kontrola.

Rezultati: Značajno umanjena aktivnost GDH nađena kod pacijenata upoređena je sa vrednošću kod kontrole grupe. Grupa pacijenata podeljena je u dve podgrupe prema srednjoj vrednosti GDH, kod niske aktivnosti kao i iznad i ispod srednje MDH vrednosti kod podgrupe 1 i podrupe 2. Aktivnost GDH je bila značajno ispod nivoa osnovne vrednosti nakon primene antipsihotične terapije kod podgrupe 2. Distribucija nonrispondera/rispondera nakon antiopsihotične terapije (prema PANSS skorivima) značajno se razlikovala između podgrupa 1 i 2. U podgrupi 1 aktivnost GDH značajno je bila u korelaciji sa PANSS skorovima nakon primene terapije.

Zaključak: Osnovna aktivnost trombocitne GDH može da posluži kao prediktor efikasnosti antipsihotične terapije kod pacijenata sa shizofrenijom.

Keywords: glutamate dehydrogenase; platelets; schizophrenia.