Changes in gene expression and methylation in the blood of patients with first-episode psychosis

DNA methylation of membrane‐bound catechol‐O‐methyltransferase in Malaysian schizophrenia patients

“…Theoretically, the overexpression of MB‐COMT should lead to increased dopamine degradation, which is consistent with the functional evidence that it plays a major role in dopamine neurotransmission and the dopamine hypothesis of schizophrenia . However, another study found that COMT mRNA expression was decreased in first‐episode schizophrenia patients; therefore, the downregulation of COMT may be an effect of dopamine hyperfunction that results in negative feedback on the synthesis of catecholamines . This trend implies that the methylation‐gene expression is a complex association, and the measurements depend on the methods used, the demographic differences, and the CpG islands studied .…”

“…15 However, another study found that COMT mRNA expression was decreased in first-episode schizophrenia patients; therefore, the downregulation of COMT may be an effect of dopamine hyperfunction that results in negative feedback on the synthesis of catecholamines. 50 This trend implies that the methylation-gene expression is a complex association, and the measurements depend on the methods used, the demographic differences, and the CpG islands studied. 17 The interactions between genotype, DNA methylation, and gene expression in schizophrenia have been documented in previous studies.…”

Oxidative stress in drug naïve first episode psychosis and antioxidant effects of risperidone

“…Patients were followed throughout the treatment, with analyses of the effects of antipsychotic on these biomarkers (Noto et al, 2015a;Ota et al, 2014a;Ota, Noto, 2014b). The study was carried out in accordance with the Declaration of Helsinki and was approved by The Research Ethics Committee of UNIFESP (Sao Paulo, Brazil).…”

“…Investigating biomarkers in the early stage of schizophrenia ascertains that the results are not affected by confounding factors including effects of antipsychotics and the chronic course of the illness. Therefore, recent researches propose to examine neurocognitive functioning, neurotransmission, brain functions, genetics and the immune system in drug naïve, first episode psychotic patients (FEP) (Kahn and Sommer, 2015;Noto et al, 2015b;Ota et al, 2014b).…”

Genetic Variation in One-Carbon Metabolism and Changes in Metabolic Parameters in First-Episode Schizophrenia Patients

“…In turn, epigenetic phenomena have been widely implicated in the etiology of obesity (van Dijk et al, 2015). In addition, a number of studies have reported that antipsychotics may influence DNA methylation (Melka et al, 2014; Ota et al, 2014; Burghardt et al, 2015; Houtepen et al, 2016; Reynolds et al, 2016). Therefore, it might be assumed that genetic variation in the MTHFR gene may influence antipsychotic-induced weight gain via interactions with epigenetic processes induced by antipsychotics.…”