A Amiotrofia Espinhal Progressiva (AEP) é uma doença autossômica recessiva que afeta os motoneurônios do corno anterior da medula espinhal, acarretando hipotonia e fraqueza muscular. A partir do conhecimento do mecanismo molecular da AEP, abriu-se um campo para testes clínicos com agentes farmacológicos que possam aumentar o nível da proteína SMN2. Diversas drogas com esta ação estão sendo testadas na tentativa de encontrar um possível tratamento para esta trágica doença. O ácido valpróico (AV), droga muito utilizada para o tratamento da epilepsia mostrou ter a propriedade de ativar o promotor do gene da proteína SMN2, aumentando a sua produção. Tendo em vista que não há uniformização do sistema de avaliação clínica dos resultados do tratamento em diferentes países, foi elaborado um protocolo selecionando métodos de avaliação fáceis, rápidos e já validados a fim de verificar se o AV é eficaz para manter ou melhorar a força muscular dos pacientes com AEP. Os métodos selecionados foram: escala Medical Research Council (MRC) para força muscular; Hammersmith motor ability score para habilidade motora; goniometria das principais articulações; cronometragem de tempo despendido para deambular, quando possível; índice de Barthel para atividades da vida diária e, por fim, um questionário para verificar as modalidades de fisioterapia e hidroterapia em uso. Vinte e dois pacientes com AEP tipo II e III, com idades variando de 2 a 18 anos, medicados com AV, foram avaliados a cada três meses durante um ano, totalizando cinco visitas, das quais a primeira ocorreu nos dias anteriores ao início do tratamento. Os resultados dos testes demonstraram que, durante o seguimento de um ano, os pacientes obtiveram melhora na habilidade motora, porém não na força muscular, o que é um resultado extremamente positivo. Crianças com idade menor ou igual a 6 anos mostraram melhores ganhos quanto à habilidade motora. / Spinal Muscular Atrophy (SMA) is an autosomal recessive disorder that affects the spinal motoneurons, resulting in hypotonia and muscle weakness. The knowledge of the molecular mechanism of SMA has originated new researches including clinical trials with pharmacological agents that increase SMN2 protein level. Many drugs with this action are being tested with the aim of finding a possible treatment for this severe disease. The valproic acid (VA), a well-known drug used to treat epilepsy has the property of activating the SMN2 gene promoter and then to increase SMN2 protein level. Since there isnt an uniform system for the clinical evaluation of the treatment results, we selected a set of easy, fast and already validated methods to evaluate if the VA is effective to stabilize or improve the motor function in patients with SMA. The selected methods were: Medical Research Council scale (MRC) to muscular strength; Hammersmith motor ability score to motor ability; goniometry of the main joints; time to walk when possible; Barthel índex for daily activities, and a questionnaire to verify the types of physiotherapy and hydrotherapy in use. Twenty two patients with SMA II and III, aged between 2 and 19 years, and treated with VA were evaluated every three months during the period of one year; the first evaluation occurred immediately before the onset of the treatment. The results of the tests demonstrated that along the period of 12 months the patients didnt gain muscle strength but improved their motor ability, that can be considered a positive result. Children aged six years or younger had a higher gain in motor ability along the period of the study.

Barn med Spinal muskelatrofi lever ett liv med begränsad rörlighet. Deras vardag innehåller att mycket träning med syfte att kunna leva ett bättre liv. I vår digitala värld finns det idag många digitala spel som syftar till träning, exempelvis Nintendo Wii-spel och det populära spelet Just Dance. Utan att vi tänker på det, tränar vi kroppen medan vi utför spelets olika moment. Men hur kan barn bibehålla motivation och hur kan immersion uppstå för att barn ska glömma rum och tid när dem tränar? Vi har i vår studie samarbetat med företaget Nordic Forest Games, som på uppdrag av ett läkemedelsföretag, utvecklar ett mobilspel för barn med Spinal muskelatrofi. Vi har undersökt vilka egenskaper ett digitalt spel bör ha för att inte upplevs som enbart träning. I studien deltar två fysioteraputer och fyra föräldrar med syfte att beskriva sina upplevelser kring deras barns vardag och hur träning och motivation upplevs. Vid analys av data har teorin Hedonic Motivation System Adoption Model (HMSAM) tillämpats för att kunna ringa in vilka olika områden som är central hos barnen för att uppleva immersion och motivation. Resultatet i studien är inte generaliserbart på grund av dels det låga antalet deltagare i studien och dels med tanke på att Spinal muskelatrofi är en ovanlig sjukdom av stor variation och mycket individuell. Utan att kunna dra någon generell slutsats har vi kunnat urskilja delar som är intressanta att studera vidare när det gäller tävlingsmoment och inkludering. Av företaget fick vi även tillgång till en prototyp av spelet. För att utvärdera prototypen gjordes en heuristisk utvärdering i enlighet med att finna användbarhetsproblem genom att se på prototypen genom Nielsens tio heuristiska riktlinjer. Med dessa två kvalitativa metoder har studien antagit en kvalitativ ansats där resultaten sedan kopplats samman med teorin HMSAM. / Children with spinal muscular atrophy live a life of limited mobility. Their everyday life includes a lot of exercise with the goal of being able to live a better life. In our digital world today, there are many digital games aimed at training, such as Nintendo Wii games and the popular game Just Dance. Without thinking about it, we train the body while performing the various steps of the game. But how can children maintain motivation and how can immersion occur for children to forget space and time when they exercise? In our study, we collaborated with the company Nordic Forest Games, which on behalf of a pharmaceutical company, develops a mobile game for children with spinal muscular atrophy. We have investigated what qualities a digital game should have in order not to be perceived as just training. Two physiotherapists and four parents participate in the study with the aim of describing their experiences of their children's everyday life and how exercise and motivation are experienced. When analyzing data, the Hedonic Motivation System Adoption Model (HMSAM) theory has been applied in order to be able to delineate which different areas are central to children in order to experience immersion and motivation. The result of the study is not generalizable due partly to the low number of participants in the study and partly given that Spinal muscular atrophy is an unusual disease of great variety and very individual. Without being able to draw any general conclusions, we have been able to distinguish parts that are interesting to study further in terms of competition elements and inclusion. The company also gave us access to a prototype of the game. To evaluate the prototype, an heuristic evaluation was made in accordance with finding usability problems by looking at the prototype through Nielsen's ten heuristic guidelines. With these two qualitative methods, the study has adopted a qualitative approach where the results are then linked to the theory HMSAM.

Situation of families in which a child with spinal muscular atrophy was born, is the topic of this thesis. This rare genetic disease affects neuromuscular system of children and shortens their lives. In most severe cases the failure of respiratory functions comes in the first year of child's life. This thesis is focused on support that Czech system of social and medical services provides to families with this disease. Next, it looks into needs of these families and examine the extent to which the system is able to saturate them. Very important point in this research is also families' perception of quality of care. The research was implemented with use of qualitative methods, mostly by semi-structured interviews which followed families' journey through the system of social and medical services. Then there is a comparison of experience of families with theories, policy and other normative framework and suggestion of steps that should be taken to improve families' satisfaction with services they receive concerning the child's disease. Key words: spinal muscular atrophy, rare diseases, patient's autonomy, patient- centered care, patient journey, quality of care.

No description available.

Spinal Muscular Atrophy with Progressive Myoclonic Epilepsy (SMA-PME), Farber Lipogranulomatosis (FL), and a rare variant form of Neonatal Progeroid Syndrome (NPS) are three monogenetic rare disorders caused by pathogenic variation in genes encoding lipid modifying proteins. FL and SMA-PME are caused by loss of function mutations in ASAH1, encoding the acid ceramidase (aCDase) enzyme. It is not, however, known how aCDase deficiency can produce either the isolated neurological symptoms of SMA-PME or the predominantly systemic symptoms of FL. Further, a recently identified variant form of NPS has been attributed to variants in ANO6, encoding a dual function calcium-activated chloride channel and glycerophosphoserine (GPS) scramblase. Here, it is not known how ANO6 mutation causes the premature aging phenotype that defines NPS. To address these questions, I sought to elucidate pathogenic changes in lipid metabolism that associate clinical phenotype. I show here that the different patient mutations in ANO6 cause a non-physiological gain of channel function and either a loss or gain of scramblase function depending on the variant expressed. Both variants, however, alter GPS metabolic homeostasis suggesting a common mechanism of action. To provide in vivo insight, I characterized a novel mouse model based on our NPS patient genetics, showing extremely low penetrance of disease symptoms in terms of live births yet confirming that affected animals show impaired GPS metabolism in affected organs. Next, I characterized the clinical presentation of six new patients with SMA-PME and identified distinct sphingolipid metabolic fingerprints in FL and SMA-PME cells. I show that FL is defined by a hypometabolic sphingolipid phenotype with cellular and molecular features of a classic lysosomal storage disorder. By contrast, SMA-PME has a hypermetabolic sphingolipid phenotype with features of non-classic lysosomal trafficking disorders. To provide clinical insight, I assessed the potential of enzyme replacement therapy, demonstrating a rescue of sphingolipid metabolism in SMA-PME patient cells. Together, this thesis identified changes in the cellular and tissue lipid profiles of patients with ANO6-NPS, SMA-PME, or FL, elucidating some of the lipid-centric pathomechanisms of these diseases.

No description available.

Objective: Activated astroglia is involved in the pathophysiology of neurodegenerative diseases and has also been described in animal models of spinal muscular atrophy (SMA). Given the urgent need of biomarkers for treatment monitoring of new RNA-modifying and gene replacement therapies in SMA, we examined glial fibrillary acidic protein concentrations in cerebrospinal fluid (cGFAP) as a marker of astrogliosis in SMA. - Methods: 58 adult patients and 21 children with genetically confirmed 5q-associated SMA from four German motor neuron disease specialist care centers and 30 age- and sex-matched controls were prospectively included in this study. cGFAP was measured and correlated to motor performance and disease severity. Additionally, we compared fL). - Results: cGFAP concentrations did not differ from controls but showed higher levels in more severely affected patients after adjustment for patients’ age. Normalized cNfL values were associated with disease severity. Within 14 months of nusinersen treatment, cGFAP concentrations did not change, while cNfL decreased significantly. - Interpretation: cGFAP is not an outstanding biomarker in SMA, but might support the hypothesis that glial activation is involved in SMA pathology. Unlike previously suggested, cNfL may be a promising biomarker also in adult patients with SMA, which should be subject to further investigations.

Spinal muscular atrophy (SMA) and Charcot-Marie-Tooth disease type 2D (CMT2D)/distal SMA type V (dSMAV) are two incurable neuromuscular disorders that predominantly manifest during childhood and adolescence. Both conditions are caused by mutations in widely and constitutively expressed genes that encode proteins with essential housekeeping functions, yet display specific lower motor neuron pathology. SMA results from recessive inactivating mutations in the survival motor neuron 1 (SMN1) gene, while CMT2D/dSMAV manifests due to dominant point mutations in the glycyl-tRNA synthetase (GlyRS) gene, GARS. Using a number of different model systems, ranging from Caenorhabditis elegans to the mouse, this thesis aimed to identify potential novel therapeutic compounds for SMA, and to increase our understanding of the mechanisms underlying both diseases. I characterised a novel C. elegans allele, which possesses a point mutation in the worm SMN1 orthologue, smn-1, and showed its potential for large-scale screening by highlighting 4-aminopyridine in a screen for compounds able to improve the mutant motility defect. Previously, the gene encoding three isoforms of chondrolectin (Chodl) was shown to be alternatively spliced in the spinal cord of SMA mice before disease onset. I performed functional analyses of the three isoforms in neuronal cells with experimentally reduced Smn levels, and determined that the dysregulation of Chodl likely reflects a combination of compensatory mechanism and contributor to pathology, rather than mis-splicing. Finally, working with two Gars mutant mice and a new Drosophila model, I have implicated semaphorin-plexin pathways and axonal guidance in the GlyRS toxic gain-of-function disease mechanism of CMT2D/dSMAV.

No description available.

Les techniques de criblage actuelles (in vitro et in silico) sont dépendantes des efforts menés en biologie médicinale pour identifier des cibles biologiques pertinentes ; cibles difficiles à définir pour les maladies génétiques dites "perte de fonction". De plus, les composés issus de ces cribles s'avèrent souvent inefficaces et/ou toxiques une fois confrontés à la complexité physiologique d'un organisme entier. Pour contourner ce problème, nous proposons d'utiliser le nématode C. elegans, notamment pour des maladies répondant aux critères suivants : i) physiopathologie complexe et/ou mal comprise excluant le développement à court terme de médicaments sur une base rationnelle, ii) peu d’espoir de thérapie génique/cellulaire à court terme, iii) conservation chez C. elegans du gène relié à la maladie humaine et induisant un phénotype exploitable une fois inactivé. Nous démontrons ici que ce petit nématode permet de tester, à moindre coût, un grand nombre de composés chimiques tout en conservant la complexité physiologique d'un animal entier. De plus, la souplesse génétique de cet animal permet d'apporter rapidement des informations sur le mode d'action des composés identifiés. Ainsi, en plus du but initial visant à identifier des molécules bioactives à intérêt thérapeutique, cette approche peut permettre de dégager de nouvelles cibles moléculaires utiles pour l'industrie chimique, et cruciales pour la recherche de traitements contre les maladies perte de fonction. Finalement, nous présentons comment mettre en place une telle stratégie, notamment pour la myopathie de Duchenne, l'amyotrophie spinale et le syndrome de Schwartz-Jampel. Enfin, nous présentons les résultats obtenus lors des différentes campagnes de criblage, les validations des molécules les plus prometteuses et les travaux effectués pour tenter de comprendre leur mode d'action chez le nématode. / Current high-throughput screening methods for drug discovery rely on the existence of targets. Moreover, most of the hits generated during screenings turn out to be invalid after further testing in animal models. To by-pass these limitations, efforts are now being made to screen chemical libraries on whole animals. One of the most commonly used animal model in biology is the murine model Mus musculus. However, its cost limits its use in large-scale therapeutic screening. In contrast, the nematode Caenorhabditis elegans is gaining momentum as screening chemical tool. This tiny worm combines genetic amenability, low cost, and culture conditions that are compatible with large-scale screens. Its main advantage is to allow high-throughput screening in a whole-animal context. Moreover, its use is not dependent on the prior identification of a target and permits the selection of compounds with an improved safety profile. Here, we introduce this approach with the Duchenne Muscular Dystrophy, the Spinal Muscular Dystrophy and the Schwartz-Jampel syndrome. We present the methodology used with each model to screen up to 7,000 compounds and the results of these screening campaigns. We further present the validation of our best hits and try to understand their mechanism of action.