BDNF, DRD4, and HTR2A Gene Allele Frequency Distribution and Association with Mental Illnesses in the European Part of Russia.

The prevalence of mental disorders and how they are diagnosed represent some of the major problems in psychiatry. Modern genetic tools offer the potential to reduce the complications concerning diagnosis. However, the vast genetic diversity in the world population requires a closer investigation of any selected populations. In the current research, four polymorphisms, namely rs6265 in BDNF, rs10835210 in BDNF, rs6313 in HTR2A, and rs1800955 in DRD4, were analyzed in a case-control study of 2393 individuals (1639 patients with mental disorders (F20-F29, F30-F48) and 754 controls) from the European part of Russia using the TaqMan SNP genotyping method. Significant associations between rs6265 BDNF and rs1800955 DRD4 and mental impairments were detected when comparing the general group of patients with mental disorders (without separation into diagnoses) to the control group. Associations of rs6265 in BDNF, rs1800955 in DRD4, and rs6313 in HTR2A with schizophrenia in patients from the schizophrenia group separately compared to the control group were also found. The obtained results can extend the concept of a genetic basis for mental disorders in the Russian population and provide a basis for the future improvement in psychiatric diagnostics.

Ceramides: Shared Lipid Biomarkers of Cardiovascular Disease and Schizophrenia.

INTRODUCTION: Schizophrenia, although a debilitating mental illness, greatly affects individuals' physical health as well. One of the leading somatic comorbidities associated with schizophrenia is cardiovascular disease, which has been estimated to be one of the leading causes of excess mortality in patients diagnosed with schizophrenia. Although the shared susceptibility to schizophrenia and cardiovascular disease is well established, the mechanisms linking these two disorders are not well understood. Genetic studies have hinted toward shared lipid metabolism abnormalities co-occurring in the two disorders, while lipid compounds have emerged as prognostic markers for cardiovascular disease. In particular, three ceramide species in the blood plasma, Cer(d18:1/16:0), Cer(d18:1/18:0), and Cer(d18:1/24:1), have been robustly linked to the latter disorder. AIM: We aimed to assess the differences in abundances of Cer(d18:1/16:0), Cer(d18:1/18:0), and Cer(d18:1/24:1) in the blood plasma of schizophrenia patients compared to healthy controls. METHODS: We measured the abundances of Cer(d18:1/16:0), Cer(d18:1/18:0), and Cer(d18:1/24:1) in a cohort of 82 patients with schizophrenia and 138 controls without a psychiatric diagnosis and validated the results using an independent cohort of 26 patients with schizophrenia, 55 control individuals, and 19 patients experiencing a first psychotic episode. RESULTS: We found significant alterations for all three ceramide species Cer(d18:1/16:0), Cer(d18:1/18:0), and Cer(d18:1/24:1) and a particularly strong difference in concentrations between psychiatric patients and controls for the ceramide species Cer(d18:1/18:0). CONCLUSIONS: The alteration of Cer(d18:1/16:0), Cer(d18:1/18:0), and Cer(d18:1/24:1) levels in the blood plasma might be a manifestation of metabolic abnormalities common to both schizophrenia and cardiovascular disease.

Plasma Neurotrophic Factor Levels are not Associated with the Severity of Depression: Prospective Pilot Study.

INTRODUCTION: Depression is one of the most common mental illnesses. Impaired neurogenesis is observed in depression. Biomarkers of impaired neurogenesis in depression can act as a useful objective and diagnostic and prognostic tool to determine the severity of depression. AIM: To study the concentration of biochemical indicators in the blood that may be involved in the pathogenesis of depression and their intercorrelations, and to determine any associations between the concentrations of biochemical indicators and severity of depressive symptoms. METHODS: We determined the plasma concentrations of serotonin, dopamine, and neurotrophic factors involved in neurogenesis (BDNF, CDNF and neuropeptide Y) using enzyme immunoassay and mass spectrometry in depressed patients (n=22) and healthy controls (n=16) matched by socio-demographic parameters. All participants were assessed using the Hamilton Depression Scale (HAMD), the Generalized Anxiety Disorder Questionnaire (GAD-7), and the Center for Epidemiologic Studies Depression Scale (CES-D) to enter the study. The standard cut-offs for the CES-D and GAD-7 scales were used to confirm the presence or absence of depression and anxiety. RESULTS: The concentrations of serotonin, dopamine, BDNF, CDNF, and neuropeptide Y in plasma did not differ between the groups and was not found to be associated with the scores on the scales. Positive correlations were found between the concentration of neuropeptide Y and serotonin, BDNF, and CDNF in blood plasma. CONCLUSIONS: Plasma concentrations of biomarkers related to the pathophysiology of depression did not correlate with the severity of its symptoms.