Reduced plasma Golga3 levels in patients with schizophrenia: a case-control study

Abstract Background and objectives Golga-3 is a protein that can increase D-serine levels by inhibiting the proteasomal breakdown of serine racemase (SR) through ubiquitination. This study aimed to compare plasma Golga-3 protein levels in patients with schizophrenia and healthy controls to determine whether changes in this protein pathway are present in patients with schizophrenia. Methods The study included 24 non-treatment-resistant schizophrenia (non-TRS) patients receiving antipsychotic monotherapy, 24 treatment-resistant schizophrenia (TRS) patients on clozapine, and 26 healthy controls matched for age, sex, education, and smoking status. Venous blood samples were collected in the morning after an overnight fast; plasma Golga3 levels were measured using an ELISA kit. Clinical assessments included the Positive and Negative Syndrome Scale (PANSS) and the Global Assessment Scale (GAS). Results Plasma Golga3 levels varied significantly across the three groups ( p < 0.001). Post-hoc analyses revealed that both non-TRS ( p = 0.001) and TRS ( p = 0.002) patients had significantly lower Golga3 levels compared to healthy controls, while no difference was observed between the two patient groups ( p = 0.722). No significant correlations were found between Golga3 levels and clinical variables. Conclusion These preliminary findings suggest that the Golga3-serine racemase pathway may be disrupted in schizophrenia; however, further studies examining D-serine levels and related metabolic markers are needed to elucidate the functional significance of reduced Golga3.