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Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a recently described familial form of ischemic stroke caused by mutations in the Notch3 gene on chromosome 19q12. Clinically, CADASIL develops as a cerebrovascular small vessel disease: against a background of repeated lacunar strokes, progressing are subcortical, pseudobulbar and cerebellar syndromes and cognitive decline. Neuroimaging methods (CT, MRI) reveal combination of small lacunar infarcts of variable location withdiffuse white matter changes (leucoaraosis). In this paper we present the first description of a Russian family with the verified mutation in the Notch3 gene, nucleotide change 832GA in exon 5 leading to substitution of valine to methionine (Val252Met) at protein codon 252. This missense mutation is novel and has not been reported before in other families with CADASIL syndrome. The observation presented confirms that CADASIL syndrome should be suspected in all cases of white matter disease of unknown origin.

Abstract The forced swim test (FST) is widely used to screen for potential antidepressant drugs and treatments. Despite this, the nature of stillness during FST and whether it resembles “depressive-like behavior” are widely debated issues. Furthermore, despite being widely used as a behavioral assay, the effects of the FST on the brain transcriptome are rarely investigated. Therefore, in this study we have investigated changes in the transcriptome of the rat hippocampus 20 min and 24 h after FST exposure. RNA-Seq is performed on the hippocampus tissues of rats 20 min and 24 h after an FST. Differentially expressed genes (DEGs) were identified using limma and used to construct gene interaction networks. Fourteen differentially expressed genes (DEGs) were identified only in the 20-m group. No DEGs were identified 24 h after the FST. These genes were used for Gene Ontology term enrichment and gene-network construction. Based on the constructed gene-interaction networks, we identified a group of DEGs (Dusp1, Fos, Klf2, Ccn1, and Zfp36) that appeared significant based on multiple methods of downstream analysis. Dusp1 appears especially important, as its role in the pathogenesis of depression has been demonstrated both in various animal models of depression and in patients with depressive disorders.

Parkinson’s disease (PD) is one of the most common human neurodegenerative diseases. Belated diagnoses of PD and late treatment are caused by its elongated prodromal phase. Thus, searching for new candidate genes participating in the development of the pathological process in the early stages of the disease in patients who have not yet received therapy is relevant. Changes in mRNA and protein levels have been described both in the peripheral blood and in the brain of patients with PD. Thus, analysis of changes in the mRNA expression in peripheral blood is of great importance in studying the early stages of PD. This work aimed to analyze the changes in MEF2C, SLC22A4, P2RY12, and LRRN3 gene expression in the peripheral blood of patients in the early stages of PD. We found a statistically relevant and PD-specific change in the expression of the LRRN3 gene, indicating a disruption in the processes of neuronal regeneration and the functioning of synapses. The data obtained during the study indicate that this gene can be considered a potential biomarker of the early stages of PD.

Summary: Genetics have nominated many schizophrenia risk genes and identified convergent signals between schizophrenia and neurodevelopmental disorders. However, functional interpretation of the nominated genes in the relevant brain cell types is often lacking. We executed interaction proteomics for six schizophrenia risk genes that have also been implicated in neurodevelopment in human induced cortical neurons. The resulting protein network is enriched for common variant risk of schizophrenia in Europeans and East Asians, is down-regulated in layer 5/6 cortical neurons of individuals affected by schizophrenia, and can complement fine-mapping and eQTL data to prioritize additional genes in GWAS loci. A sub-network centered on HCN1 is enriched for common variant risk and contains proteins (HCN4 and AKAP11) enriched for rare protein-truncating mutations in individuals with schizophrenia and bipolar disorder. Our findings showcase brain cell-type-specific interactomes as an organizing framework to facilitate interpretation of genetic and transcriptomic data in schizophrenia and its related disorders.

Transcriptomic analysis conducted by us previously revealed upregulation of genes involved in low-density lipoprotein particle receptor (LDLR) activity pathway in lethal COVID-19 caused by SARS-CoV-2 virus (severe acute respiratory syndrome coronavirus 2). Last data suggested the possible role of extracellular vesicles in COVID-19 pathogenesis. The aim of the present study was to retrospectively evaluate parameters of cholesterol metabolism and newly identified EVs, exomeres, as possible predictors of fatal outcome of COVID-19 patients infected by the Alpha and the Delta variants of SARS-CoV-2 virus. Blood from 67 patients with severe COVID-19 were collected at the time of admission to the intensive care unit (ICU) and 7 days after admission to the ICU. After 30 days patients were divided into two subgroups according to outcome-34 non-survivors and 33 survivors. This study demonstrated that plasma low- and high-density lipoprotein cholesterol levels (LDL-C and HDL-C) were decreased in non-survivors compared to controls at the time of admission to the ICU. The conjoint fraction of exomeres and LDL particles measured by dynamic light scattering (DLS) was decreased in non-survivors infected by the Alpha and the Delta variants compared to survivors at the time of admission to the ICU. We first showed that reduction of exomeres fraction may be critical in fatal outcome of COVID-19.

Anna Kiseleva,1,* Marina Klimushina,1,* Evgeniia Sotnikova,1,* Olga Skirko,1 Mikhail Divashuk,1,2 Olga Kurilova,1 Alexandra Ershova,1 Eleonora Khlebus,1 Anastasia Zharikova,1,3,4 Irina Efimova,1 Maria Pokrovskaya,1 Petr A Slominsky,5 Svetlana Shalnova,1 Alexey Meshkov,1,* Oxana Drapkina1,* 1Federal State Institution «National Medical Research Center for Therapy and Preventive Medicine» of the Ministry of Healthcare of the Russian Federation, Moscow, 101000, Russia; 2Kurchatov Genomics Center-ARRIAB, All-Russia Research Institute of Agricultural Biotechnology, Moscow 127550, Russia; 3Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow 119991, Russia; 4Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow 127051, Russia; 5Institute of Molecular Genetics, Russian Academy of Sciences, Moscow 123182, Russia*These authors contributed equally to this workCorrespondence: Anna Kiseleva Email sanyutabe@gmail.comPurpose: Cystic fibrosis (CF) is one of the most common monogenic diseases with an autosomal recessive inheritance. Carrier screening leads to a reduction in the number of children born with CF disease. The aim of this study was to develop the custom panel for the diagnosis of heterozygous carriage of polymorphic variants in the CFTR gene and to establish their allelic frequencies (AF) in one of the Russian regions where ethnic Russians predominate.Patients and Methods: The diagnostic panel was designed on the basis of data from the register of CF patients in Russia for 2017 and validated on 22 blood samples of patients with previously genetically established CF. The study participants (n=642) for CF variants estimation were randomly selected from the population-based cohort study ESSE-Vologda. Genotypes were determined by real-time PCR on the QuantStudio 12K Flex Real-Time PCR System. Data processing was performed using the TaqMan Genotyper Software.Results: The proposed diagnostic panel allowed simultaneous analysis of 60 variants of the CFTR gene. A total of 23 carriers of the following variants were identified among 642 participants: F508del (rs113993960) with a frequency of 2.02%, L138ins (rs397508686) and 394delTT (rs121908769) – 0.47%, CFTRdele2.3 (c.54– 5940_273+10250del21080; p.S18Rfs*16) – 0.31%, R117H (rs78655421), and G542X (rs113993959) – 0.16%. The frequency of heterozygotes in the Russian population was 3.58% or 1:28 (CI95%: 2.28– 5.33% by Clopper–Pearson exact method).Conclusion: High frequency of heterozygous CFTR variants carriers and availability of highly productive diagnostic panel for detection of CFTR variants suggest the prospect of carrier screening for some common CF variants among Russian population.Keywords: cystic fibrosis, CFTR, genetic analysis, carrier screening, carrier testing

The reduced expression of the HCN1 ion channel in the somatosensory cortex (SSC) and mesolimbic dopamine deficiency are thought to be associated with the genesis of spike-wave discharges (SWDs) and comorbid depression in the WAG/Rij rat model of absence epilepsy. This study aimed to investigate whether the maternal methyl-enriched diet (MED), which affects DNA methylation, can alter DNMT1, HCN1, and TH gene expression and modify absence seizures and comorbid depression in WAG/Rij offspring. WAG/Rij mothers were fed MED (choline, betaine, folic acid, vitamin B12, L-methionine, zinc) or a control diet for a week before mating, during pregnancy, and for a week after parturition. MED caused sustained suppression of SWDs and symptoms of comorbid depression in the offspring. Disease-modifying effects of MED were associated with increased expression of the DNMT1 and HCN1 genes in the SSC and hippocampus, as well as DNMT1, HCN1, and TH genes in the nucleus accumbens. No changes in gene expression were detected in the hypothalamus. The results indicate that maternal MED can suppress the genetic absence epilepsy and comorbid depression in offspring. Increased expression of the DNMT1, HCN1, and TH genes is suggested to be a molecular mechanism of this beneficial phenotypic effect.

Abstract Background Hypertrophic cardiomyopathy (HCM), described as the presence of hypertrophy of left ventricular, is the most prevalent heritable cardiovascular disease with predominantly an autosomal dominant type of inheritance. However, pathogenic alleles are not identified in at least 25% of patients with HCM, and the spectrum of pathogenic variants that contribute to the development of HCM in Russia has not been fully described. Therefore, the goal of our study was to identify genetic variants associated with the etiopathogenesis of HCM in Russian patients. Methods The study cohort included 98 unrelated adult patients with HCM. We performed targeted exome sequencing, an analysis using various algorithms for prediction of the impact of variants on protein structure and the prediction of pathogenicity using ACMG Guidelines. Results The frequency of pathogenic and likely pathogenic variants in all HCM‐related genes was 8% in our patients. We also identified 20 variants of uncertain significance in all HCM‐related genes. Conclusions The prevalence of individual pathogenic variants in HCM‐related genes in Russian population appears to be lower than in general European population, which could be explained by ethnic features of Russian population, age characteristics of our sample, or unidentified pathogenic variants in genes previously not linked with HCM.

Parkinson’s disease (PD) is a common chronic progressive multifactorial neurodegenerative disease. In most cases, PD develops as a sporadic idiopathic disease. However, in 10%–15% of all patients, Mendelian inheritance of the disease is observed in an autosomal dominant or autosomal recessive manner. To date, mutations in seven genes have been convincingly confirmed as causative in typical familial forms of PD, i.e., SNCA, LRRK2, VPS35, PRKN, PINK1, GBA, and DJ-1. Family and genome-wide association studies have also identified a number of candidate disease genes and a common genetic variability at 90 loci has been linked to risk for PD. The analysis of the biological function of both proven and candidate genes made it possible to conclude that mitochondrial dysfunction, lysosomal dysfunction, impaired exosomal transport, and immunological processes can play important roles in the development of the pathological process of PD. The mechanisms of initiation of the pathological process and its earliest stages remain unclear. The study of the early stages of the disease (before the first motor symptoms appear) is extremely complicated by the long preclinical period. In addition, at present, the possibility of performing complex biochemical and molecular biological studies familial forms of PD is limited. However, in this case, the analysis of the state of the central nervous system can only be assessed by indirect signs, such as the level of metabolites in the cerebrospinal fluid, peripheral blood, and other biological fluids. One of the potential solutions to this problem is the analysis of disease models, in which it is possible to conduct a detailed in-depth study of all aspects of the pathological process, starting from its earliest stages. Many modeling options are available currently. An analysis of studies published in the 2000s suggests that toxic models in rodents are used in the vast majority of cases. However, interesting and important data for understanding the pathogenesis of PD can be obtained from other in vivo models. Within the framework of this review, we will consider various models of PD that were created using various living organisms, from unicellular yeast (Saccharomyces cerevisiae) and invertebrate (Nematode and Drosophila) forms to various mammalian species.

Parkinson’s disease (PD) is one of the most common neurodegenerative diseases. Investigating individuals with the most identical genetic background is optimal for minimizing the genetic contribution to gene expression. These individuals include monozygotic twins discordant for PD. Monozygotic twins have the same genetic background, age, sex, and often similar environmental conditions. The aim of this study was to carry out a transcriptome analysis of the peripheral blood of three pairs of monozygotic twins discordant for PD. We identified the metabolic process “circadian behavior” as a priority process for further study. Different expression of genes included in the term “circadian behavior” confirms that this process is involved in PD pathogenesis. We found increased expression of three genes associated with circadian behavior, i.e., PTGDS, ADORA2A, and MTA1, in twins with PD. These genes can be considered as potential candidate genes for this disease.

Processes of intracellular and extracellular transport play one of the most important roles in the functioning of cells. Changes to transport mechanisms in a neuron can lead to the disruption of many cellular processes and even to cell death. It was shown that disruption of the processes of vesicular, axonal, and synaptic transport can lead to a number of diseases of the central nervous system, including Parkinson’s disease (PD). Here, we studied changes in the expression of genes whose protein products are involved in the transport processes (Snca, Drd2, Rab5a, Anxa2, and Nsf) in the brain tissues and peripheral blood of mice with MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine)-induced models of PD. We detected changes in the expressions of Drd2, Anxa2, and Nsf at the earliest modeling stages. Additionally, we have identified conspicuous changes in the expression level of Anxa2 in the striatum and substantia nigra of mice with MPTP-induced models of PD in its early stages. These data clearly suggest the involvement of protein products in these genes in the earliest stages of the pathogenesis of PD.

A critical aspect of real-time PCR is the presence of housekeeping genes (HKGs) as an internal control for the normalization of expression data for genes of interest. It is necessary to select correct HKGs in the investigation of various pathologies. Thereby, we analyzed the stability of expression of the HKGs in Parkinson’s disease (PD). The work was carried out in the peripheral blood of patients with PD and in the brain tissues and peripheral blood of mice with MPTP-induced PD. As a result, Aars was the most stably expressed HKG in the mouse brain as a whole. However, different genes were more stably expressed in different parts of the brain. Polr2f was the most stably expressed in the cortex, Psmd6 was the most stably expressed in the cerebellum, and Psmd7 was the most stably expressed in the striatum and substantia nigra. HKGs were different in similar tissues of the studied organisms. Polr2f was the most stably expressed HKG in the peripheral blood of mice, whereas PSMD6 was the most stably expressed gene in humans. Thus, there is no universal HKG both for different brain tissues of one organism and for similar tissues of different organisms. Furthermore, the identified most stably expressed HKGs can be considered as such only under conditions in PD.

Major depressive disorder (MDD) is a heterogeneous disease affecting one out of five individuals and is the leading cause of disability worldwide. Presently, MDD is considered a multifactorial disease with various causes such as genetic susceptibility, stress, and other pathological processes. Multiple studies allowed the formulation of several theories attempting to describe the development of MDD. However, none of these hypotheses are comprehensive because none of them can explain all cases, mechanisms, and symptoms of MDD. Nevertheless, all of these theories share some common pathways, which lead us to believe that these hypotheses depict several pieces of the same big puzzle. Therefore, in this review, we provide a brief description of these theories and their strengths and weaknesses in an attempt to highlight the common mechanisms and relationships of all major theories of depression and combine them together to present the current overall picture. The analysis of all hypotheses suggests that there is interdependence between all the brain structures and various substances involved in the pathogenesis of MDD, which could be not entirely universal, but can affect all of the brain regions, to one degree or another, depending on the triggering factor, which, in turn, could explain the different subtypes of MDD.

It was shown that the anxiolytic effect of Selank is comparable to that of classical benzodiazepine drugs and that the basis of their mechanism of action may be similar. These data suggest that the presence of Selank may change the action of classical benzodiazepine drugs. To test this hypothesis, we evaluated the anxiolytic activity of Selank and diazepam in rats both under conditions of unpredictable chronic mild stress and in its absence, after the individual and combined administration of these compounds using the elevated plus maze test. We found that, even in the absence of chronic stress, the administration of a course of test substances changed anxiety indicators toward their deterioration, but the changes after the administration of a course of Selank were less pronounced. In conditions of chronic stress, anxiety indicator values after the simultaneous use of diazepam and Selank did not differ from the respective values observed before chronic stress exposure. The data obtained indicate that the individual administration of Selank was the most effective in reducing elevated levels of anxiety, induced by the administration of a course of test substances, whereas the combination of diazepam with Selank was the most effective in reducing anxiety in unpredictable chronic mild stress conditions.