MicroRNA Expression Profile Changes in the Leukocytes of Parkinson's Disease Patients.

Parkinson's disease (PD) is one of the most common movement disorders. It is primarily diagnosed clinically. A correct diagnosis of PD in its early stages is important for the development of a pathogenic treatment, which necessitates a search for potential biomarkers of the disease. We evaluated the diagnostic value of several microRNAs and their relationship with the clinical characteristics of PD. The study included 70 PD patients and 40 healthy volunteers. We analyzed the expression of 15 microRNAs in blood leukocytes, which were selected based on literature data and modern concepts of molecular PD pathogenesis. All patients were evaluated using the Hoehn and Yahr scale, UPDRS, NMSQ, and PDQ-39. The data analysis revealed a statistically significant increase in the expression of miR-7-5p, miR-29c-3p, and miR-185-5p and a statistically significant decrease in the expression of miR-29a-3p and miR-30c-1-5p in leukocytes in PD. However, the altered microRNA profile was shown to have a moderate diagnostic value for PD diagnosis. MicroRNA expression changes were associated with the motor and non-motor phenotypic features of PD and administration of anti-Parkinson's drugs. Also, a relationship between some of the microRNAs studied and the duration and severity of PD was found, which may potentially be used to monitor disease progression.

[Spinocerebellar ataxia type 8 in Russian patients]. / Spinotserebellyarnaya ataksiya 8-go tipa u rossiiskikh bol'nykh.

OBJECTIVE: To assess the incidence of spinocerebellar ataxia type 8 (SCA8) in patients with progressive cerebellar ataxia and describe the clinical features of the SCA8 phenotype in Russian patients. MATERIAL AND METHODS: Genotyping of CTA/CTG repeats in ATXN8OS gene was carried out in 411 patients with degenerative ataxias using fragment analysis. SCA types 1, 2, 3 and 6 as well as Friedreich's ataxia were preliminarily excluded. All patients underwent brain MRI study. Scale for the Assessment and Rating of Ataxia (SARA), and the Montreal Cognitive Assessment Scale (MoCA) to screen for cognitive impairment were used. RESULTS: Six patients with SCA8 (1.5%) were identified as carriers of the expansion in the ATXN8OS gene (91-152 CTA/CTG repeats). All cases were sporadic. Age of onset ranged from 14 to 42 years. All patients had slowly progressive cerebellar ataxia, oculomotor disturbances, dysarthria, pyramidal signs, and two patients had cognitive impairment. In one patient the clinical presentation corresponded to multiple system atrophy cerebellar type (ataxia, orthostatic hypotension, cerebellum and brainstem atrophy). Brain MRI study in all patients revealed cerebellar atrophy. CONCLUSION: SCA8 is a rare form of autosomal dominant ataxia with a predominance of the classical phenotype. All identified cases of SCA8 were sporadic, which should be taken into account when planning genetic testing in patients with spinocerebellar ataxia.

[Spinocerebellar ataxia 17: full phenotype in a 42 CAG/CAA-repeats carrier]. / Spinotserebellyarnaya ataksiya 17-go tipa: polnyi fenotip u nositelya 42 CAG/CAA-povtorov.

Spinocerebellar ataxia 17 (SCA17) is one of the most heterogeneous forms of autosomal dominant cerebellar ataxia with a wide clinical spectrum, which can imitate other motor disorders. The article presents an observation of a 51-year-old woman with slowly progressive coordination disorders and changes in handwriting manifested at the age of 39 years. Neurologic examination reveals severe cerebellar ataxia, choreiform hyperkinesis, polyneuropathy, cognitive and mental disorders; magnetic resonance imaging (MRI) of the brain shows moderate diffuse atrophy of the cerebral cortex, severe atrophy of the cerebellum hemispheres. Molecular analysis of the TBP demonstrates an allele with 42 CAG/CAG-repeats suggesting that an allele of this size could be an allele associated with the full clinical spectrum of SCA17.

C9orf72 Gene Expression in Frontotemporal Dementia and Amyotrophic Lateral Sclerosis.

We studied the expression of C9orf72 gene in pathologies associated with hexanucleotide repeats expansion in this gene: frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). The study included 7 patients with hexanucleotide repeats expansion in the C9orf72 gene and 9 patients of the control group. The expression of C9orf72 mRNA was evaluated in blood leukocytes by real-time PCR. Methylation of CpG-sites in C9orf72 promotor region was evaluated by DNA sequencing after bisulfite conversion. A 2-fold decrease in the C9orf72 gene expression was found in patients with hexanucleotide repeats expansion in comparison with controls, though the difference did not reach statistical significance due to small sample size. The highest expression was shown for ALS in comparison with FTD and FTD-ALS phenotype. A trend to inverse correlation between C9orf72 mRNA level and promoter methylation of this gene as well as between mRNA level and age of disease onset was demonstrated.

The SNCA-Rep1 Polymorphic Locus: Association with the Risk of Parkinson's Disease and SNCA Gene Methylation.

Neurodegeneration in Parkinson's disease is characterized by the accumulation of alpha-synuclein, a protein encoded by the SNCA gene, in neurons. In addition to mutations, many polymorphisms have been identified in this gene, and one of these is a dinucleotide microsatellite: SNCA-Rep1. The mechanisms by which specific configurations of SNCA-Rep1 may contribute to the development of this disease have yet to be clarified. In our study, a relationship between long SNCA-Rep1 alleles and Parkinson's was confirmed in the Russian population. Long allelic variants of SNCA-Rep1 were shown to be associated with the hypomethylation of the CpG-sites in intron 1 of the SNCA gene. Long variants of SNCA-Rep1 are supposed to exert their effect through the hypomethylation of a transcriptionally significant region of this gene. Hypomethylation is usually associated with increased expression, which, in turn, contributes to alpha-synuclein accumulation in neuronal cytoplasm, with the latter being the main molecular marker of Parkinson's disease. Further studies are needed to establish a relationship between our finding and SNCA gene expression.

Generation of induced pluripotent stem cell line ICGi018-A from peripheral blood mononuclear cells of a patient with Huntington's disease.

Huntington's disease (HD) is an autosomal dominant neurodegenerative disease caused by CAG repeat expansion in the HTT gene. HD patient-specific induced pluripotent stem cells (iPSCs) represent an excellent model for the disease study. We generated iPSC line from blood mononuclear cells of HD patient with 38 CAG repeats in the HTT exon 1 using integration free episomal plasmids expressing Yamanaka factors. The iPSC line retained the disease causing mutation and expressed pluripotency markers. It also displayed a normal karyotype and the ability to differentiate into derivatives of three germ layers.

[Epigenetic regulation of clinical manifestations of Friedreich's disease]. / Épigeneticheskaia reguliatsiia klinicheskikh proiavlenii bolezni Fridreikha.

AIM: To study a methylation profile of FXN gene and its influence on the clinical phenotype of Friedreich's desease (FD). MATERIAL AND METHODS: The methylation pattern was analyzed in 17 patients with FD. Forty-five CpG-sites in the promoter region and the region of intron 1 of FXN: before the GAA-expansion (UP-GAA) and after the GAA-expansion (DOWN-GAA), were studied. RESULTS: Correlations between the methylation level of CpG-sites in UP-GAA and DOWN-GAA and the number of GAA repeats in both expanded FXN alleles in patients with FD were found. An analysis revealed an earlier onset and a more severe course of FD in cases with hypermethylation of several CpG-sites in the UP-GAA region. The correlation between the methylation pattern and the presence of extraneural manifestations of FD was also revealed. In FD patients with cardiomyopathy, a hypomethylated CpG-site in the promoter region was found. In FD patients with carbohydrate metabolism disorders, two hypomethylated CpG-sites in the DOWN-GAA region were observed. CONCLUSION: The results indicate a significant contribution of epigenetic modifications of FXN to the clinical presentation of FA.

Effect of Mutations in SOD1 and C9orf72 Genes on Autophagy in Lymphomonocytes in Myotrophic Lateral Sclerosis.

Insoluble protein inclusions accumulate in somatic cells in amyotrophic lateral sclerosis. The most common gene mutations associated with this pathology are SOD1 and C9orf72. Protein aggregates can be removed from cells by autophagy. We studied the relationship between the presence of genetic abnormalities in the SOD1 and C9orf72 genes and changes in autophagy in lymphomonocytes in amyotrophic lateral sclerosis. The study included 85 patients with amyotrophic lateral sclerosis and 15 healthy volunteers. Genetic analysis for the presence of mutations in the SOD1 and C9orf72 genes and detection of autophagy marker LC3 in lymphomonocytes were performed. In amyotrophic lateral sclerosis, autophagy activation in lymphomonocytes was found. We also obtained evidence that protein product of the mutant C9orf72 gene can disturb the late stages of autophagy.

[Diagnostic algorithm for autosomal recessive ataxia]. / Algoritm diagnostiki autosomno-retsessivnykh ataksii.

AIM: To develop a complex algorithm for autosomal recessive ataxia (ARA) diagnosis applicable for Russian patients with degenerative ataxias. MATERIAL AND METHODS: 48 patients with of presumably degenerative ataxias were examined. Clinical evaluation was performed with the use of the SARA and ICARS scales (for ataxia) and MoCA (cognitive functions), and a set of laboratory tests was carried out, including electromyography, brain MRI, and DNA analysis of mutations responsible for Friedreich's disease and spinocerebellar ataxias (SCAs) types 1, 2, 3, 6 and 17. 28 patients underwent mutation screening using a multigenic MPS panel. RESULTS: 8 patients (16.7%) with non-hereditary causes of ataxia were identified: cerebellar alcoholic degeneration (n = 6) and multiple system atrophy of cerebellar type (n = 2); 3 patients (6.3%) with genetic ataxias were identified using routine DNA tests, such as with SCA type 1, 2 and 17, and 9 (18.8%) patients with Friedreich's disease. The MPS panel enabled molecular diagnosis of ARA in 8 patients (28.6%): ataxia-telangiectasia (n = 2), SANDO syndrome (n = 2), ataxia with oculomotor apraxia type 2 (n = 1), SCAR10 (n = 1), SCAR16 (n = 1), and atypical form of neuroaxonal dystrophy (n = 1). The diagnosis was not established in 20 patients. CONCLUSION: We have proposed an appropriate algorithm for degenerative ataxia diagnosis which is recommended to be used when examining patients with sporadic and autosomal recessive cases of the disorders with dyscoordination of movements.

Generation of induced pluripotent stem cell line, ICGi007-A, by reprogramming peripheral blood mononuclear cells from a patient with Huntington's disease.

Huntington's disease (HD) is an autosomal dominant neurodegenerative disease caused by mutation in the HTT gene encoding HTT protein. The mutant protein leads to the neuronal death through dysregulation of multiple cellular processes. HD human induced pluripotent stem cells (iPSCs) represent a useful and valid model for the disease study. iPSC line from HD patient with 47 CAG repeats in HTT was generated from blood mononuclear cells by non-integrating episomal vectors. The iPSC line retained the mutation, expressed pluripotency markers, had a normal karyotype and displayed in vitro differentiation to the three germ layers. Resource table.

[Differential diagnosis of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy]. / Differentsial'naia diagnostika tserebral'noi autosomno-dominantnoi arteriopatii s podkorkovymi infarktami i leikoéntsefalopatiei.

Cerebral autosomal dominant arteriopathy with subcortical infarctions and leucoencephalopathy (CADASIL) is an inherited CNS disease, which is caused by mutations in the NOTCH3 gene. Selective disorders of small vessels underlie the disease pathogenesis. Clinically CADASIL is characterized by headaches, multiple stroke-like disorders (in most cases transient ischemic attacks and lacunar strokes), and different focal neurological symptoms and dementia. There are specific MRI signs of the disease: multiple lacunar infarctions located in the basal ganglia, brain steam and cerebellum, focal lesions of temporal poles, capsula externa, periventricular and subcortical areas; diffuse white matter changes and leukoaraiosis can be observed as well. The differential diagnosis of CADASIL is made with many diseases, which are manifested by multiple brain matter lesions, including demyelinating disorders. It should be taken into account that CADASIL is characterized by headaches as one of the initial symptoms, multiple lacunar and diffuse brain matter lesions based on MRI data with an absence of atherosclerosis and arterial hypertension. Family history and autosomal dominant mode of inheritance is also typical of CADASIL. Detection of the NOTCH3 gene mutation is necessary for the definite diagnosis of CADASIL.

[Identification of people at the latent stage of Parkinson's disease (the PARKINLAR study): first results and an optimization of the algorithm].

AIM: To work out an optimal algorithm to identify people at the latent stage of neurodegenerative process of «parkinsonian¼ type in the Russian population. MATERIAL AND METHODS: Authors launched a two-step study aimed at identifying people at the latent stage of Parkinson's disease (PD) in the Russian population - the PARKINLAR (PARKINsonism, LAtent stage, Russia). As the first step, we formed a group of «primary risk¼ by the identification in neurologically healthy people of at least one of the following confirmed PD risk factors: a) the substantia nigra hyperechogenicity (ultrasound screening was performed in 193 people); b) mutations in «parkinsonian¼ genes (genetic screening was performed in 29 relatives of PD patients from families with LRRK2, PARK2 and GBA mutations). Thereby, 37 people comprised the «primary risk¼ group, of whom 23 agreed to continue further examination (44±10.2 years). A matched group of people without the aforementioned primary biomarkers of PD served as control. As the second step, we undertook in the prescreened groups a complex of investigations assessing the presence of secondary («minor¼) biomarkers of PD: Sniffin' Sticks olfactory testing; color visual evoked potentials; analysis of goal-directed eye-head-hand movements with the use of a special neuro-cybernetic system; assessment of motor and non-motor symptoms with the use of UPDRS and NMSS scales. RESULTS: When comparing the «primary risk¼ group with controls, maximal differences in the occurrence of symptoms were seen for goal-directed eye movements (43.5% vs. 20.0%) and color vision (39.1% vs. 26.7%). Among these individuals, we found two people with 4 secondary biomarkers and one with 3, and no such observations in controls. People with the combination of a primary biomarker with several secondary biomarkers of PD comprised a group of «high risk¼ in our study. CONCLUSION: Optimization of this algorithm of population screening of people predisposed to the development of PD may be done by expanding the spectrum of biomarkers and assessing their validity in a long-term prospective observational study.

Hospital-based surveillance of rotavirus and other viral agents of diarrhea in children and adults in Russia, 2005-2007.

During a 2-year period in 2005-2007, we conducted surveillance of group A rotaviruses and other enteric agents among patients hospitalized with acute gastroenteritis in 8 different cities of the Russian Federation. Fecal specimens were gathered from 3208 children (including 2848 children aged <5 years) and 1354 adults who were admitted to hospitals in Moscow, St. Petersburg, Chelyabinsk, Nizhnii Novgorod, Tyumen, Khabarovsk, Makhachkala, and Yakutsk. Polymerase chain reaction was performed to detect rotaviruses of groups A and C, noroviruses of genogroups I and II, astrovirus, sapovirus, and enteric adenoviruses (group F). Group A rotavirus was the most common viral pathogen detected among children aged <5 years (43.6%), followed by norovirus (12.5%), whereas norovirus was the pathogen most commonly detected in adults (11.9%). P and G genotypes were determined for 515 rotavirus specimens, and the most prevalent genotypes were G1P[8] (44.9%), G4P[8] (40.0%), G2P[4] (8.5%), and G3P[8] (6.6%). This study is the first multicenter study of rotaviruses in the Russian Federation and documents the important burden of disease caused by this pathogen, which soon may be preventable by vaccination.