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The dopamine, serotonin and glutamate systems are jointly involved in the pathogenesis and pharmacotherapy of schizophrenia. We formulated a hypothesis that polymorphic variants of the GRIN2A, GRM3, and GRM7 genes may be associated with the development of hyperprolactinemia in patients with schizophrenia taking conventional and atypical antipsychotics as basic treatment. 432 Caucasian patients diagnosed with schizophrenia were examined. DNA was isolated from peripheral blood leukocytes using the standard phenol-chloroform method. For pilot genotyping, 12 SNPs in the GRIN2A gene, 4 SNPs in the GRM3 gene, and 6 SNPs in the GRM7 gene were selected. Allelic variants of the studied polymorphisms were determined by real-time PCR. The level of prolactin was determined by enzyme immunoassay. Among persons taking conventional antipsychotics, there were statistically significant differences in the distribution of genotype and allele frequencies in groups of patients with normal and elevated prolactin levels for the GRIN2A rs9989388 and GRIN2A rs7192557 polymorphic variants, as well as differences in serum prolactin levels depending on the genotype of the GRM7 rs3749380 polymorphic variant. Among persons taking atypical antipsychotics, statistically significant differences were found in the frequencies of genotypes and alleles of the GRM3 rs6465084 polymorphic variant. An association of polymorphic variants of the GRIN2A, GRM3, and GRM7 genes with the development of hyperprolactinemia in patients with schizophrenia taking conventional and atypical antipsychotics has been established for the first time. The identified associations of polymorphic variants of the GRIN2A, GRM3 and GRM7 genes with the development of hyperprolactinemia in patients with schizophrenia taking conventional and atypical antipsychotics have been established for the first time. These associations not only confirm the close connection of the dopaminergic, serotonergic, and glutamatergic systems in the development of schizophrenia, but also demonstrate the potential of taking into account the genetic component during therapy.

Background: Metabolic syndrome is widespread in patients with schizophrenia receiving long-term antipsychotic therapy. Dopamine D2 receptors play an important role in mediating both the therapeutic actions of antipsychotics and their side effects. The present study examined the association of two polymorphisms of the DRD2 gene with metabolic syndrome in patients with schizophrenia., Methods: We examined 517 patients from several regions of Siberia (Russia) with a clinical diagnosis of schizophrenia. Genotyping of two single nucleotide polymorphisms rs1799732 and rs4436578 of the dopamine D2 receptor gene (DRD2) was performed in a population of 471 patients. The results were analyzed using chi-square tests., Results: Functional polymorphism rs1799732 of the DRD2 gene is associated with drug-induced metabolic syndrome in women with schizophrenia., Conclusions: Our results show that the DRD2 gene may be involved in the pathogenesis of metabolic disorders in patients with schizophrenia. Further analysis of possible genetic markers will allow for personalized treatment with minimal side effects and optimal efficacy. This which seems relevant in light of the recent focus on improving the quality of life and ensuring a high level of social adaptation of patients with schizophrenia.

Background: Metabolic syndrome (MetS) is a common complication of long-term treatment of persons with schizophrenia taking (atypical) antipsychotics. In this study, we investigated the existence of an association with polymorphisms of genes for four hormones that regulate energy metabolism., Methods: We recruited 517 clinically admitted white patients (269M/248F) with a verified diagnosis of schizophrenia (ICD-10) and with a stable physical condition. Participants were classified for having or not having MetS and genotyped for 20 single-nucleotide polymorphisms (SNPs) in the genes encoding insulin-induced gene 2 ( INSIG2 ), ghrelin ( GHRL ), leptin ( LEP ), and leptin receptor ( LEPR )., Results: The 139 patients (26.9%) with MetS were significantly more likely to be women, older, and ill longer, and had a larger body mass index (BMI). Four polymorphisms (rs10490624, rs17587100, rs9308762, and rs10490816) did not meet the Hardy-Weinberg equilibrium (HWE) criterion and were excluded. Only genotypes and alleles of the rs3828942 of LEP gene (chi2 = 7.665, p = 0.022; chi2 = 5.136, p = 0.023) and the genotypes of the rs17047718 of INSIG2 gene (chi2 = 7.7, p = 0.021) had a significant association with MetS., Conclusions: The results of our study suggest that the LEP and INSIG2 genes play a certain causal role in the development of MetS in patients with schizophrenia.

Background: Schizophrenia is a severe highly heritable mental disorder. The clinical heterogeneity of schizophrenia is expressed in the difference in the leading symptoms and course of the disease. Identifying the genetic variants that affect clinical heterogeneity may ultimately reveal the genetic basis of the features of schizophrenia and suggest novel treatment targets. PIP5K2A (Phosphatidylinositol-4-Phosphate 5-Kinase Type II Alpha) has been investigated as a potential susceptibility gene for schizophrenia., Methods: In this work, we studied the possible association between eleven polymorphic variants of PIP5K2A and the clinical features of schizophrenia in a population of 384 white Siberian patients with schizophrenia. Genotyping was carried out on QuantStudio 5 Real-Time PCR System with a TaqMan Validate SNP Genotyping Assay (Applied Biosystems, USA)., Results: PIP5K2A rs8341 (χ 2  = 6.559, p = 0.038) and rs946961 (χ 2  = 5.976, p = 0.049) showed significant association with course of schizophrenia (continuous or episodic). The rs8341*CT (OR = 1.63, 95% CI: 1.04-2.54) and rs946961*CC (OR = 5.17, 95% CI: 1.20-22.21) genotypes were associated with a continuous type of course, while the rs8341*TT genotype (OR = 0.53, 95% CI: 0.29-0.97) was associated with an episodic type of course of schizophrenia. Therefore rs8341*TT genotype presumably has protective effect against the more severe continuous course of schizophrenia compared to the episodic one., Conclusions: Our experimental data confirm that PIP5K2A is a genetic factor influencing the type of course of schizophrenia in Siberian population. Disturbances in the phosphatidylinositol pathways may be a possible reason for the transition to a more severe continuous course of schizophrenia.

Objective: Schizophrenia is a severe highly heritable mental disorder. Genetic polymorphisms of dopaminergic pathways are related to pathogenesis of drug response. Hyperprolactinemia (HPRL), a common adverse effect of antipsychotics, is attributed to blockade of dopamine D2 receptors. Ankyrin Repeat and Kinase Domain containing 1 (ANKK1) gene is closely related to Dopamine Receptor D2 type (DRD2) gene functioning. We examined whether the functional polymorphism rs2734849 in the ANKK1 gene is associated with antipsychotic-induced HPRL., Methods: We recruited 446 patients with schizophrenia from among the Russian population of the Siberian region. The polymorphism rs2734849 in the ANKK1 gene was genotyped with The MassARRAY® Analyzer 4 by Agena Bioscience™, using the kit SEQUENOM Consumables iPLEXGold 384. Genotype and allele frequencies were compared between groups of schizophrenia patients with and without HPRL using the χ 2 test., Results: A comparison between schizophrenia patients with and without HPRL revealed significantly higher frequency of the C allele of the polymorphic variant rs2734849 in the ANKK1 gene in patients with HPRL as compared to the patients without it (χ 2 = 3.70; p = .05; odds ratio [OR] = 1.30 [0.99-1.69])., Conclusion: The functional polymorphism rs2734849 in the ANKK1 gene was associated with HPRL in patients with schizophrenia., (© 2020 The Authors. Human Psychopharmacology: Clinical and Experimental published by John Wiley & Sons Ltd.)

The article presents current literature data on genetic studies of neurocognitive deficit in schizophrenia, including the genes of neurotransmitter systems (dopaminergic, glutamatergic, and serotonergic); genes analyzed in genome-wide association studies (GWAS), as well as other genetic factors related to the pathophysiological mechanisms underlying schizophrenia and neurocognitive disorders.

Objectives: Acetylcholine M (muscarinic) receptors are possibly involved in tardive dyskinesia (TD). The authors tried to verify this hypothesis by testing for possible associations between two muscarinic receptor genes ( CHRM1 and CHRM2 ) polymorphisms and TD in patients with schizophrenia. Methods: A total of 472 patients with schizophrenia were recruited. TD was assessed cross-sectionally using the Abnormal Involuntary Movement Scale. Fourteen allelic variants of CHRM1 and CHRM2 were genotyped using Applied Biosystems amplifiers (USA) and the MassARRAY System by Agena Bioscience. Results: The prevalence of the rs1824024*GG genotype of the CHRM2 gene was lower in TD patients compared to the group without it (χ2 = 6.035, p  = 0.049). This suggested that this genotype has a protective effect for the development of TD (OR = 0.4, 95% CI: 0.19-0.88). When age, gender, duration of schizophrenia and dosage of antipsychotic treatment were added as covariates in regression analysis, the results did not reach statistical significance. Conclusions: This study did identify associations between CHRM2 variations and TD; the results of logistic regression analysis with covariates suggest that the association is, however, likely to be secondary to other concomitant factors.

Background: Hyperprolactinemia (HPRL) is a classical side effect of antipsychotic drugs primarily attributed to blockade of dopamine D2 receptors (DRD2s) on the membranes of lactotroph cells within the pituitary gland. Certain antipsychotic drugs, e.g. risperidone, are more likely to induce HPRL because of relative accumulation within the adenohypophysis. Nevertheless, due to competition for pituitary DRD2s by high dopamine levels may limit antipsychotic-induced HPRL. Moreover, the activity of prolactin-producing lactotrophs also depends on other hormones which are regulated by the extra-pituitary activity of dopamine receptors, dopamine transporters, enzymes of neurotransmitter metabolism and other factors. Polymorphic variants in the genes coding for these receptors and proteins can have functional significance and influence on the development of hyperprolactinemia., Methods: A set of 41 SNPs of genes for dopamine receptors DRD1, DRD2, DRD3, DRD4, the dopamine transporter SLC6A3 and dopamine catabolizing enzymes MAOA and MAOB was investigated in a population of 446 Caucasians (221 males/225 females) with a clinical diagnosis of schizophrenia (according to ICD-10: F20) with and without HPRL who were treated with classical and/or atypical antipsychotic drugs. Additive genetic model was tested and the analysis was carried out in the total group and in subgroup stratified by the use of risperidone/paliperidone., Results: One statistically significant association between polymorphic variant rs1799836 of MAOB gene and HPRL in men was found in the total group. Furthermore, the rs40184 and rs3863145 variants in SLC6A3 gene appeared to be associated with HPRL in the subgroup of patients using the risperidone/paliperidone, but not with HPRL induced by other antipsychotic drugs., Conclusions: Our results indicate that genetic variants of MAOB and SLC6A3 may have consequences on the modulation of prolactin secretion. A further search for genetic markers associated with the development of antipsychotic-related hyperprolactinemia in schizophrenic patients is needed.

Aim: To test the main hypothesis that the deficit phenomena in schizophrenia act not in the 'pure' form, but in the form of aggravating personality characteristics, forming so-called 'common' syndromes with personality disorders (PD)., Material and Methods: The results of the psychopathological study (with the use of psychometric methods) of deficit disorders in a sample of 170 patients with schizophrenia and schizophrenia spectrum disorders (63 men, 107 women) are presented in relation to the abnormal structure of premorbid personality (PD of clusters A, B, C). An analysis of negative symptoms according to the comparability of defect to the profile of premorbid personality made it possible to distinguish three groups of deficit states associated with PD - 'common syndromes': defensive schizoidy by the type of deficit schizoid and expansive schizoidy by the type of 'verschroben' (cluster A); pathological hysterical infantilism, malignant hysteria and defective erotomania (cluster B); pseudo-psychasthenia and pathological rationalism (cluster C)., Results: It has been found that the symptomatology of 'common syndromes' is subject to patterns reflecting the dichotomy of the basic defect. This pattern is valid not only for one single cluster of PD, but extends to all psychopathy-like disorders, regardless of their affiliation with a particular cluster. The pathocharacterological component of the 'common syndromes' coexisting with the deficit symptom complexes is subject to the basic deficit component of the defect and is separated into polar dimensions (defensive-expansive) within specific clusters of PD, and then unified in accordance with the dichotomy of schizophrenic defect in categories with the predominance of emotional or apathoabulic disorders., Conclusion: Psychopathy-like symptom complexes in the space of 'common syndromes' can be qualified as a psychopathological construct secondary to basic deficit disorders, and their isolation as an independent entity of negative disorders appears to be unjustified.

Aim: To study the phenomena of visual-hemispatial neglect in healthy people and patients with brain diseases of different genesis., Material and Methods: Eighty-eight patients with schizophrenia spectrum disorders, 68 patients with exogenous organic brain diseases and 240 healthy adults of different age were included in the study. The digit cancellation test modified by the authors was used., Results and Conclusion: The validity of the modified digit cancellation test was approved and its age standards were obtained. In healthy right-handed people, there was the bias of attention focus to the left, the decrease of asymmetry intensity of visual-spatial inattention during physiological aging and the presence of some clinical peculiarities of neglect in schizophrenia spectrum disorders and lateralized organic damages of the brain. This variant of the test can be recommended for practical use as the sensitive psychometric tool.

Objectives: Hyperprolactinaemia (HPRL) is a classical side effect of antipsychotic drugs primarily attributed to blockade of dopamine D2 subtype receptors in the pituitary gland. Although dopamine is considered the primary factor inhibiting prolactin release, the activity of prolactin-producing lactotrophs is also regulated by the secretagogues thyrotrophin releasing hormone, vasoactive intestinal polypeptide and serotonin (5-hydroxytryptamine; 5-HT)., Methods: We describe the association between HPRL and a set of 29 SNPs from 5-HT receptor genes HTR1A, HTR1B, HTR2A, HTR2C, HTR3A, HTR3B and HTR6 in a population of 446 Caucasians (221 males/225 females) with a clinical diagnosis of schizophrenia (according to ICD-10: F20) who were treated with classical and/or atypical antipsychotic drugs., Results: None of the studied autosomal markers were found to be associated with HPRL. However, a significant association was established between various HTR2C polymorphisms and HPRL., Conclusions: This study revealed an association between HPRL and X-chromosome haplotypes comprised of the rs569959 and rs17326429 polymorphisms.

Background: Antipsychotic drugs can cause hyperprolactinemia. However, hyperprolactinemia was also observed in treatment-naive patients with a first schizophrenic episode. This phenomenon might be related to the role of prolactin as a cytokine in autoimmune diseases. Extrapituitary prolactin production is regulated by an alternative promoter, which contains the functional single nucleotide polymorphism -1149 G/T (rs1341239). We examined whether this polymorphism was associated with hyperprolactinemia in patients with schizophrenia., Method: We recruited 443 patients with schizophrenia and 126 healthy controls. The functional polymorphism -1149 G/T (rs1341239) in the prolactin gene was genotyped with multiplexed primer extension, combined with MALDI-TOF mass spectrometry. Genotype and allele frequencies were compared between groups with the χ 2 test and logistic regression models adjusting for covariates., Results: The frequency of genotypes and alleles in patients with schizophrenia did not differ from those in control subjects. A comparison between patients with schizophrenia with and without hyperprolactinemia revealed significantly higher frequency of the G allele in patients with hyperprolactinemia than in patients without it (χ 2 =7.25; p=0.007; OR=1.44 [1.10-1.89]). Accordingly, patients with hyperprolactinemia carried the GG genotype more frequently than patients without hyperprolactinemia (χ 2 =9.49; p=0.009). This association remained significant after adjusting the estimates for such covariates as sex, age, duration of the diseases and the dose of chlorpromazine equivalents., Conclusion: This study revealed a significant association between the polymorphic variant rs1341239 and the development of hyperprolactinemia in patients with schizophrenia. The serum prolactin concentration in patients with schizophrenia treated with antipsychotics may provide an indication of the activity of the gene that regulates extrapituitary prolactin production which is believed to play a role in the immune system., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The relevance of this study is the high prevalence and clinical heterogeneity of deficit states in chronic schizophrenia and schizophrenia spectrum disorders. The study aimed at analyzing negative symptoms in schizophrenia and schizophrenia spectrum disorders from historical and modern perspectives. An analysis of available literature, along with own observations, has been performed. It was found that negative symptoms comprise 3 clinical types: 1) 'pseudopsychopathic' type (overlapping personality dimensions and premorbid/initial negative symptoms), 2) pseudoorganic/asthenic/pseudobradiphrenic type (pseudoorganic states), developing at different stages of schizophrenia), 3) 'new'-life pseudopsychopathic type (not associated with premorbid personality traits), developing at late stages in schizophrenia. The trajectory heterogeneity of negative symptoms in their relation to positive symptoms has been defined: simultaneous-continuous course (synchronous course of positive and negative symptoms), polar course (alternative development of predominantly positive or negative symptoms), simultaneous-phasic course (pseudopsychopathic negative symptoms, attracting depressive symptoms, or depression that exacerbates latent deficit). The authors discuss some aspects of psychopharmacological treatment of negative symptoms. Negative symptoms in schizophrenia and schizophrenia spectrum disorders differ clinically, have heterogeneous trajectory course, and require differentiated approach with regard to psychopathological qualification, prognosis and treatment.

A replicative analysis of associations of 15 SNPs located in the regions of 11 genes (TCF4, VRK2, NOTCH4, ZNF804A, AGBL1, RELN, ZFP64P1, KCNB2, CSMD1, CPVL, NRIP1) and three intergenic regions (SLCO6A1/LINCOO491, LOC105376248/LOC105376249, SPA17/NRGN) with schizophrenia was conducted in the Russian population of the Siberian region. These SNPs were previously identified in genome-wide association studies (GWAS) of schizophrenia and cognitive abnormalities. The present study confirmed associations of KCNB2 rs2247572, CSMD1 rs2616984, and intergenic rs12807809 located in SPA17/NRGN with schizophrenia. It was established that the frequency of the CSMD1 rs2616984 G/G genotype was higher in patients compared to the control group (OR = 1.73; CI: 1.14–2.62; р = 0.0337). The frequencies of the KCNB2 rs2247572 TT genotype (OR = 0.41; CI: 0.20–0.87; р = 0.0485) and intergenic rs12807809 CT genotype located in SPA17/NRGN (OR = 0.70; CI: 0.53–0.94; р = 0.0464) were significantly decreased in patients compared to the control group.

Polymorphic variants of CYP1A2 and CYP2D6 genes of the cytochrome P450 system were studied in patients with schizophrenia with drug-induced motor disorders and hyperprolactinemia against the background of long-term neuroleptic therapy. We revealed an association of polymorphic variant C-163A CYP1A2*1F of CYP1A2 gene with tardive dyskinesia and association of polymorphic variant 1846G>A CY2D6*4 and genotype A/A of CYP2D6 gene (responsible for debrisoquin-4-hydroxylase synthesis) with limbotruncal tardive dyskinesia in patients with schizophrenia receiving neuroleptics for a long time.

Objectives: The aim of this study was to investigate a possible association between tardive dyskinesia (TD) and CYP1A2 (*1F, -163C>А, rs762551) polymorphism in Russian psychiatric inpatients., Methods: TD was assessed cross-sectionally using the Abnormal Involuntary Movement Scale (AIMS). Orofacial and limb-truncal dyskinesia were assessed with AIMS 1-4 and 5-7, respectively. Standard protocols were applied for genotyping. Analysis of covariance (ANCOVA) was used to compare the mean AIMS scores for each of the genotypic classes., Results: A total of 319 Caucasian patients from West Siberia with schizophrenia and 117 healthy volunteers were investigated. No significant differences between the patients and the controls in genotype frequencies were found. Analysis of covariance (ANCOVA) with age, sex, duration of disease, chlorpromazine equivalent (CPZEQ) incorporated as covariates showed that limb-truncal, but not orofacial TD, is associated with CYP1A2 (-163C>, rs762551) polymorphism (F = 3.27, P = 0.039). Patients with the C/C genotype had a higher mean AIMS 5-7 score than those with the A/C or the A/A genotype., Conclusions: Our results support the hypothesis that not only with clozapine, but also with other classical and atypical antipsychotics, smoking may decrease plasma levels; this is most extensively expressed in carriers of the CYP1A2*1F (-163C> A) polymorphism.

EEG study of 5-7 years boys with autism revealed lower values of coherence in background delta, theta and alpha bands and higher values of coherence in background beta 1, beta 2 and gamma bands. Healthy boys showed higher values of beta and gamma coherence during cognitive task. Autistic persons demonstrated higher values of theta coherence during cognitive task.

Background: Tardive dyskinesia is a disorder characterized by involuntary muscle movements that occur as a complication of long-term treatment with antipsychotic drugs. It has been suggested to be related to a malfunctioning of the indirect pathway of the motor part of the cortical-striatal-thalamic-cortical circuit, which may be caused by oxidative stress-induced neurotoxicity., Methods: The purpose of our study was to investigate the possible association between phosphatidylinositol-4-phosphate-5-kinase type IIa (PIP5K2A) function and tardive dyskinesia in 491 Caucasian patients with schizophrenia from 3 different psychiatric institutes in West Siberia. The Abnormal Involuntary Movement Scale was used to assess tardive dyskinesia. Individuals were genotyped for 3 single nucleotide polymorphisms in PIP5K2A gene: rs10828317, rs746203, and rs8341., Results: A significant association was established between the functional mutation N251S-polymorphism of the PIP5K2A gene (rs10828317) and tardive dyskinesia, while the other 2 examined nonfunctional single nucleotide polymorphisms were not related., Conclusions: We conclude from this association that PIP5K2A is possibly involved in a mechanism protecting against tardive dyskinesia-inducing neurotoxicity. This corresponds to our hypothesis that tardive dyskinesia is related to neurotoxicity at striatal indirect pathway medium-sized spiny neurons., (© The Author 2015. Published by Oxford University Press on behalf of CINP.)