Effects of Human Alpha-Synuclein A53T-A30P Mutations on SVZ and Local Olfactory Bulb Cell Proliferation in a Transgenic Rat Model of Parkinson Disease

A transgenic Sprague Dawley rat bearing the A30P and A53T α-synuclein (α-syn) human mutations under the control of the tyrosine hydroxylase promoter was generated in order to get a better understanding of the role of the human α-syn mutations on the neuropathological events involved in the progression of the Parkinson's disease (PD). This rat displayed olfactory deficits in the absence of motor impairments as observed in most early PD cases. In order to investigate the role of the mutated α-syn on cell proliferation, we focused on the subventricular zone (SVZ) and the olfactory bulbs (OB) as a change of the proliferation could affect OB function. The effect on OB dopaminergic innervation was investigated. The human α-syn co-localized in TH-positive OB neurons. No human α-syn was visualized in the SVZ. A significant increase in resident cell proliferation in the glomerular but not in the granular layers of the OB and in the SVZ was observed. TH innervation was significantly increased within the glomerular layer without an increase in the size of the glomeruli. Our rat could be a good model to investigate the role of human mutated α-syn on the development of olfactory deficits

Pathological lesions in colonic biopsies during Parkinson's disease.

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Subjective sleep dysfunction and insomnia symptoms in Parkinson's disease: Insights from a cross-sectional evaluation of the French CoPark cohort

Introduction: Twenty-seven to 80% of patients with Parkinson's Disease (PD) complain of subjective sleep dysfunction and insomnia symptoms. Our aim is to describe the prevalence and features of subjective sleep dysfunction and insomnia symptoms in patients with PD compared to other patients. Methods: Cross-sectional analysis of 636 adult PD patients compared to 143 age and sex-matched non-PD control patients consulting their general practitioners. Insomnia symptoms and other sleep features were assessed by the Pittsburgh Sleep Quality Index (PSQI), a global score > 5 defining impaired sleep. The Chi-square test or the Student's t-test were used to assess the potential clinical and demographic differences between groups and between PD patients with vs. without sleep dysfunction. Logistic regression analysis was employed to test multivariate effects. Results: Sleep dysfunction and insomnia symptoms were more frequent in PD patients compared to control patients (63 vs. 45%, p = 0.001). Female gender, PD duration, presence of depression and anxiety were associated with the presence of insomnia in PD. Subjective sleep efficiency, habitual sleep quality, sleep disturbance and daytime dysfunction, but not sleep latency, were reduced in PD patients compared to controls. Conclusions: The prevalence of sleep dysfunction is higher in PD than in other general medical conditions. Insomnia in PD seems to affect sleep maintenance and consolidation, but not sleep onset.Fil: Ratti, Pietro Luca. Université Paul Sabatier; Francia. Inserm; Francia. Sleep and Epilepsy Center; Suiza. Toulouse University Hospital; FranciaFil: Negre Pages, Laurence. Toulouse University Hospital; Francia. Université Paul Sabatier; FranciaFil: Pérez Lloret, Santiago. Toulouse University Hospital; Francia. Université Paul Sabatier; Francia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Cardiológicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Cardiológicas; ArgentinaFil: Manni, Raffaele. Istituto di Ricovero e Cura a Carattere Scientifico. Istituto Neurologico Nazionale a Carattere Scientifico; ItaliaFil: Damier, Philippe. Universite de Nantes; FranciaFil: Tison, Francois. Universite de Bordeaux; FranciaFil: Destée, Alain. Centre Hospitalier Universitaire de Lille. Pôle de Neurologie. Service de Neurologie et pathologie du mouvement; FranciaFil: Rascol, Olivier. Toulouse University Hospital; Francia. Inserm; Francia. Toulouse University Hospital; Francia. Université Paul Sabatier; Franci

Falls in ambulatory non-demented patients with Parkinson's disease

This study aimed at determining the prevalence of falling in PD patients, to assess generic and disease-specific clinical and pharmacological factors, relationship with health-related quality of life (HR-QoL) and changes in falls from OFF to ON in patients with motor fluctuations. Six-hundred and eighty-three PD patients of the COPARK survey were evaluated (11 had missing data and were excluded from the analysis). Patients with falls were identified as those with a UPDRS Item 13 ¡Ý 1 in the ON condition. All patients were assessed in a standardized manner [demographics, treatments, Unified PD Rating Scale (UPDRS), Hospital Anxiety and Depression Scale, Pittsburg questionnaire and HR-QoL scales (SF36, PDQ39)]. Falling was reported by 108/672 (16 %) PD patients during the ON state and prevalence increased according to PD severity, from 5 % in Hoehn and Yahr stage 1-60 % in stage 4. Falling was significantly related to lower HR-QoL. Falling correlated with (1) generic factors such as female gender, age at the end of academic studies and diuretics consumption, (2) motor PD-specific factors including disease severity, frozen gait, difficulties when arising from a chair, dyskinesia and higher levodopa daily equivalent dose and (3) non-motor PD-specific factors such as orthostatic hypotension and hallucinations. Falling was more frequent in OFF than in ON in 48/74 (64 %) patients with motor fluctuations and remained unchanged in 27 patients (36 %). In summary, falling affected a significant proportion of PD patients, especially in advanced stages. It was associated with a variety of generic and PD-specific factors and was related to reduced HR-QoL.Fil: Rascol, Olivier. NS-Park Network; Francia. Université Paul Sabatier; Francia. Inserm; FranciaFil: Pérez Lloret, Santiago. Université Paul Sabatier; Francia. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Instituto de Investigaciones Biomédicas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; ArgentinaFil: Damier, Philippe. Hôpital Laënnec; Francia. NS-Park Network; Francia. Inserm; FranciaFil: Delval, Arnaud. Seul Centre Hospitalier Universitaire; FranciaFil: Derkinderen, Pascal. Hôpital Laënnec; FranciaFil: Destée, Alain. NS-Park Network; Francia. Inserm; Francia. Seul Centre Hospitalier Universitaire; FranciaFil: Meissner, Wassilios G.. Universite de Bordeaux; Francia. Institut des Maladies Neurodégénératives; Francia. Centre Hospitalier Universitaire de Bordeaux; FranciaFil: Tison, Francois. Universite de Bordeaux; Francia. Centre Hospitalier Universitaire de Bordeaux; Francia. Institut des Maladies Neurodégénératives; Francia. NS-Park Network; FranciaFil: Negre Pages, Laurence. Inserm; Francia. NS-Park Network; Franci

EIF4G1 in familial Parkinson's disease: pathogenic mutations or rare benign variants?

International audienceMutations in the eukaryotic translation initiation factor 4-gamma (EIF4G1) gene, encoding a component of the eIF4F translation initiation complex, were recently reported as a possible cause for the autosomal dominant form of Parkinson's disease (PD). Here, we describe the screening of all 31 EIF4G1 coding exons in a series of 251 index cases with autosomal dominant PD, mostly of French origin and in 236 European control subjects. We identified 12 rare coding variants (either nonsynonymous amino acid substitutions or in frame deletions/insertions), including 6 variants present only in cases and 3 in controls. Segregation was possible only for 1 variant (p.E462delInsGK) that was found in 2 affected siblings. In addition, we found 2 previously reported pathogenic variants in 2 isolated patients (p.G686C) and in a control subject (p.R1197W). These data do not support the pathogenicity of several EIF4G1 variants in PD, at least in the French population

Association of Rare Genetic Variants in Opioid Receptors with Tourette Syndrome

Background: Genes involved in Tourette syndrome (TS) remain largely unknown. We aimed to identify genetic factors contributing to TS in a French cohort of 120 individuals using a combination of hypothesis-driven and exome-sequencing approaches. Methods: We first sequenced exons of SLITRK1-6 and HDC in the TS cohort and subsequently sequenced the exome of 12 individuals harboring rare variants in these genes to find additional rare variants contributing to the disorder under the hypothesis of oligogenic inheritance. We further screened three candidate genes (OPRK1, PCDH10, and NTSR2) preferentially expressed in the basal ganglia, and three additional genes involved in neurotensin and opioid signaling (OPRM1, NTS, and NTSR1), and compared variant frequencies in TS patients and 788 matched control individuals. We also investigated the impact of altering the expression of Oprk1 in zebrafish. Results: Thirteen ultrarare missense variants of SLITRK1-6 and HDC were identified in 12 patients. Exome sequencing in these patients revealed rare possibly deleterious variants in 3,041 genes, 54 of which were preferentially expressed in the basal ganglia. Comparison of variant frequencies altering selected candidate genes in TS and control individuals revealed an excess of potentially disrupting variants in OPRK1, encoding the opioid kappa receptor, in TS patients. Accordingly, we show that downregulation of the Oprk1 orthologue in zebrafish induces a hyperkinetic phenotype in early development. Discussion: These results support a heterogeneous and complex genetic etiology of TS, possibly involving rare variants altering the opioid pathway in some individuals, which could represent a novel therapeutic target in this disorder

Correction: Association of Rare Genetic Variants in Opioid Receptors with Tourette Syndrome.

[This corrects the article DOI: 10.5334/tohm.464.]

Exhaustive analysis of BH4 and dopamine biosynthesis genes in patients with Dopa-responsive dystonia

Dopa-responsive dystonia is a childhood-onset dystonic disorder, characterized by a dramatic response to low dose of l-Dopa. Dopa-responsive dystonia is mostly caused by autosomal dominant mutations in the GCH1 gene (GTP cyclohydrolase1) and more rarely by autosomal recessive mutations in the TH (tyrosine hydroxylase) or SPR (sepiapterin reductase) genes. In addition, mutations in the PARK2 gene (parkin) which causes autosomal recessive juvenile parkinsonism may present as Dopa-responsive dystonia. In order to evaluate the relative frequency of the mutations in these genes, but also in the genes involved in the biosynthesis and recycling of BH4, and to evaluate the associated clinical spectrum, we have studied a large series of index patients (n = 64) with Dopa-responsive dystonia, in whom dystonia improved by at least 50% after l-Dopa treatment. Fifty seven of these patients were classified as pure Dopa-responsive dystonia and seven as Dopa-responsive dystonia-plus syndromes. All patients were screened for point mutations and large rearrangements in the GCH1 gene, followed by sequencing of the TH and SPR genes, then PTS (pyruvoyl tetrahydropterin synthase), PCBD (pterin-4a-carbinolamine dehydratase), QDPR (dihydropteridin reductase) and PARK2 (parkin) genes. We identified 34 different heterozygous point mutations in 40 patients, and six different large deletions in seven patients in the GCH1 gene. Except for one patient with mental retardation and a large deletion of 2.3 Mb encompassing 10 genes, all patients had stereotyped clinical features, characterized by pure Dopa-responsive dystonia with onset in the lower limbs and an excellent response to low doses of l-Dopa. Dystonia started in the first decade of life in 40 patients (85%) and before the age of 1 year in one patient (2.2%). Three of the 17 negative GCH1 patients had mutations in the TH gene, two in the SPR gene and one in the PARK2 gene. No mutations in the three genes involved in the biosynthesis and recycling of BH4 were identified. The clinical presentations of patients with mutations in TH and SPR genes were strikingly more complex, characterized by mental retardation, oculogyric crises and parkinsonism and they were all classified as Dopa-responsive dystonia-plus syndromes. Patient with mutation in the PARK2 gene had Dopa-responsive dystonia with a good improvement with l-Dopa, similar to Dopa-responsive dystonia secondary to GCH1 mutations. Although the yield of mutations exceeds 80% in pure Dopa-responsive dystonia and Dopa-responsive dystonia-plus syndromes groups, the genes involved are clearly different: GCH1 in the former and TH and SPR in the late

Repetitive Behaviours in Patients with Gilles de la Tourette Syndrome: Tics, Compulsions, or Both?

Background Repetitive behaviours (RB) in patients with Gilles de la Tourette syndrome (GTS) are frequent. However, a controversy persists whether they are manifestations of obssessive-compulsive disorder (OCD) or correspond to complex tics. Methods 166 consecutive patients with GTS aged 15–68 years were recruited and submitted to extensive neurological, psychiatric and psychological evaluations. RB were evaluated by the YBOCS symptom checklist and Mini International Neuropsychiatric Interview (M.I.N.I), and classified on the basis of a semi-directive psychiatric interview as compulsions or tics. Results RB were present in 64.4% of patients with GTS (107/166) and categorised into 3 major groups: a ‘tic-like’ group (24.3%–40/166) characterised by RB such as touching, counting, ‘just right’ and symmetry searching; an ‘OCD-like’ group (20.5%–34/166) with washing and checking rituals; and a ‘mixed’ group (13.2%–22/166) with both ‘tics-like’ and ‘OCD-like’ types of RB present in the same patient. In 6.3% of patients, RB could not be classified into any of these groups and were thus considered ‘undetermined’. Conclusions The results confirm the phenomenological heterogeneity of RB in GTS patients and allows to distinguish two types: tic-like behaviours which are very likely an integral part of GTS; and OCD-like behaviours, which can be considered as a comorbid condition of GTS and were correlated with higher score of complex tics, neuroleptic and SSRIs treatment frequency and less successful socio-professional adaptation. We suggest that a meticulous semiological analysis of RB in GTS patients will help to tailor treatment and allow to better classify patients for future pathophysiologic studies. Trial Registration ClinicalTrials.gov NCT0016935

Colonic Biopsies to Assess the Neuropathology of Parkinson's Disease and Its Relationship with Symptoms

The presence of Lewy bodies and Lewy neurites (LN) has been demonstrated in the enteric nervous system (ENS) of Parkinson's disease (PD) patients. The aims of the present research were to use routine colonoscopy biopsies (1) to analyze, in depth, enteric pathology throughout the colonic submucosal plexus (SMP), and (2) to correlate the pathological burden with neurological and gastrointestinal (GI) symptoms.A total of 10 control and 29 PD patients divided into 3 groups according to disease duration were included. PD and GI symptoms were assessed using the Unified Parkinson's Disease Rating Scale part III and the Rome III questionnaire, respectively. Four biopsies were taken from the ascending and descending colon during the course of a total colonoscopy. Immunohistochemical analysis was performed using antibodies against phosphorylated alpha-synuclein, neurofilaments NF 220 kDa (NF) and tyrosine hydroxylase (TH). The density of LN, labeled by anti-phosphorylated alpha-synuclein antibodies, was evaluated using a quantitative rating score. Lewy pathology was apparent in the colonic biopsies from 21 patients and in none of the controls. A decreased number of NF-immunoreactive neurons per ganglion was observed in the SMP of PD patients compared to controls. The amount of LN in the ENS was inversely correlated with neuronal count and positively correlated with levodopa-unresponsive features and constipation.Analysis of the ENS by routine colonoscopy biopsies is a useful tool for pre-mortem neuropathological diagnosis of PD, and also provides insight into the progression of motor and non-motor symptoms