No description available.

Amyotrophic Lateral Sclerosis (ALS), also known as Lou Gehrig’s disease, is an adult-onset, progressive and fatal neurodegenerative disease. Pathologically, it is characterized by a loss of motor neurons in the spinal cord, brain stem and motor cortex leading to progressive muscle weakness, atrophy, and death. ALS presents as both a sporadic (SALS) and familial (FALS) illness. Interestingly, over 100 mutations of the CuZn-Superoxide Dismutase (SOD1) gene have been reported to be dominantly inherited in ALS families. SOD1 is a 17KD protein that contains one copper and one zinc atom. The known function of this enzyme is to convert superoxide to oxygen and hydrogen peroxide. It was first thought that the toxicity of different SOD1 mutants linked to ALS resulted from decreased free-radical scavenging activity. However, studies show that mutant SOD1 enzymes cause motor neuron degeneration via a gain of harmful properties. The nature of the gain-of-toxic function in mutant SOD1 is not clear. Recent studies suggest that SOD1 itself is a target of oxidative stress. Human SOD1 has four cysteine residues, Cys6, Cys57, Cys111, and Cys146. An internal disulfide bond exists between Cys57 and Cys146. This disulfide bond is highly conserved in SOD1, making the protein considerably strong, while the remaining two cysteine residues are free and prone to post-translational modifications. Here we show that free cysteine residues in SOD1 are available to be modified by mal PEG (Maleimide polyethylene glycol) and AMS, and that this modification decreases with disease progression. Our data suggests that cysteine residues in SOD1 are post-translationally modified and may play a significant role in the development of the disease.

Amyotrophic Lateral Sclerosis (ALS), also known as Lou Gehrig’s disease, is an adult-onset, progressive and fatal neurodegenerative disease. Pathologically, it is characterized by a loss of motor neurons in the spinal cord, brain stem and motor cortex leading to progressive muscle weakness, atrophy, and death. ALS presents as both a sporadic (SALS) and familial (FALS) illness. Interestingly, over 100 mutations of the CuZn-Superoxide Dismutase (SOD1) gene have been reported to be dominantly inherited in ALS families. SOD1 is a 17KD protein that contains one copper and one zinc atom. The known function of this enzyme is to convert superoxide to oxygen and hydrogen peroxide. It was first thought that the toxicity of different SOD1 mutants linked to ALS resulted from decreased free-radical scavenging activity. However, studies show that mutant SOD1 enzymes cause motor neuron degeneration via a gain of harmful properties. The nature of the gain-of-toxic function in mutant SOD1 is not clear. Recent studies suggest that SOD1 itself is a target of oxidative stress. Human SOD1 has four cysteine residues, Cys6, Cys57, Cys111, and Cys146. An internal disulfide bond exists between Cys57 and Cys146. This disulfide bond is highly conserved in SOD1, making the protein considerably strong, while the remaining two cysteine residues are free and prone to post-translational modifications. Here we show that free cysteine residues in SOD1 are available to be modified by mal PEG (Maleimide polyethylene glycol) and AMS, and that this modification decreases with disease progression. Our data suggests that cysteine residues in SOD1 are post-translationally modified and may play a significant role in the development of the disease.

Bakgrund: ALS är en progressiv obotlig sjukdom som påverkar nervsystemet och överlevnaden är mellan 3-5 år. Omvårdnadsåtgärder bör sättas in i ett tidigt skede och fokus bör ligga på den unika patienten men även familjen påverkas. Katie Erikssons (1994) omvårdnadsteori om lidande valdes som referensram eftersom vården bör sträva efter att lindra patienters lidande. Därför behövs en större förståelse för hur patienter upplever sin sjukdom. Syfte: Att beskriva patienters upplevelser av att leva med ALS. Metod: En systematisk litteraturstudie där nio artiklar med både kvalitativ och kvantitativ ansats ingick. Resultat: De kategorier som framkom var Upplevelser av förändrade relationer, Upplevelser av begränsningar och Upplevelser av välbefinnande. Lidande kunde upplevas som sjukdomslidande, vårdlidande och livslidande i olika sammanhang. Förändrade relationer med stöd från familjen, men även oro för familjen och deras framtid, påverkade patienternas upplevelse av sin sjukdom. Begränsningar kunde vara fysiska symtom men även upplevelser av att vara en börda och inte bli sedd som en person. Upplevelser av välbefinnande innebar känslor av meningsfullhet, hopp och acceptans. Slutsats: Patienter med ALS upplevde både fysiska begränsningar, oro och rädsla för framtiden men även välbefinnande. Individanpassad vård som utgår från den unika patienten kan lindra lidande och gemensamma insatser med samverkan i team kan utveckla vården och ge patienten en ännu bättre omvårdnad.

No description available.

No description available.

Amyotrophic lateral sclerosis (ALS) is characterized by adult-onset degeneration of upper and lower motor neurons. Symptoms begin focally in one muscle and then spread contiguously, resulting in progressive paralysis and death from respiratory failure. Hexanucleotide repeat expansion in C9ORF72 is the most common genetic cause, however, mutations in SOD1 were the first identified and are found in 1-9% of patients. Misfolded SOD1 aggregates in the CNS are hallmarks of ALS associated with SOD1 mutations. However, accumulation of misfolded or aggregated SOD1 protein has also been reported in sporadic and familial ALS without SOD1 mutations, suggesting that wild-type SOD1 could play a role in ALS pathology in general. The aims of this thesis are: 1) To describe the resulting disease phenotype and specific characteristics of the SOD1 protein carrying the stable disease- associated mutation L117V. 2) To set up cell-based in vitro models to study the mechanisms of SOD1 misfolding and aggregation under physiologically relevant expression levels. 3) To compare SOD1 activity in patient-derived samples and screen for underlying causes of deviant SOD1 activities in individuals lacking SOD1 mutations. 1) We identified a novel L117V SOD1 mutant in two families of Syrian origin that co-segregated with the disease. This mutation was associated with slow disease progression, reduced penetrance and a uniform phenotype. The L117V mutant protein was indistinguishable from wild-type SOD1 in terms of stability, dismutation activity and misfolding in patient-derived cell lines. 2) We established patient-derived fibroblast and iPSC-MN lines expressing mutant SOD1 at physiological levels as in vitro models to study misfolding and aggregation of SOD1. We investigated the effects of several cellular pathway disturbances on SOD1 misfolding. Misfolded SOD1 was increased by inhibition of the ubiquitin-proteasome pathway in fibroblasts derived from both patients and controls. An age-related decline in proteasome activity could contribute to the late onset of ALS. Next, we studied the effects of low oxygen tension on misfolding and aggregation of SOD1 in patient-derived cells. Low O2 tensions were found to markedly increase C57-C146 disulphide reduction, misfolding and aggregation of SOD1. Importantly, the largest effects were detected in iPSC-MNs. This suggests that motor neurons are specifically vulnerable to misfolding and aggregation of SOD1 under low O2 tension. 3) We compared the enzymatic activity of SOD1 in blood samples from a large number of ALS patients and controls. We screened for potential underlying causes of deviant SOD1 activities in individuals lacking SOD1 mutations. No aberrations in copy number, other large structural changes in introns and exons or intronic mutations in the 30-50 bp flanking the exons were found in the 142 outliers, with either very low or very high SOD1 dismutation activities. However, hemoglobinopathies, including thalassemias and iron deficiency anemia, were associated with high SOD1/mg Hb ratios. Erythrocytes from patients with destabilizing SOD1 mutations showed half the normal activity. There were no significant differences in SOD1 activity between control individuals and ALS patients without a coding SOD1 mutation, or carriers of TBK1 mutations or the hexanucleotide repeat expansion in C9ORF72. Our result suggests that SOD1 enzymatic activity is not associated with the disease in non-SOD1 mutation ALS.

Amyotrophic Lateral Sclerosis (ALS) is a progressive neurodegenerative disease affecting upper and lower motor neurons. Although many cellular processes such as cytoskeletal maintenance and synaptic function are disrupted in ALS, the molecular mechanisms by which these defects arise remain poorly understood. TDP-43, an RNA binding protein linked to the majority of ALS cases, is involved in multiple aspects of RNA metabolism. It is hypothesized that TDP-43 may sequester its mRNA targets into cytoplasmic stress granules during disease progression in turn, inhibiting their localization and/or translation. This work uses a Drosophila model of ALS based on TDP-43, to provide evidence for TDP-43’s role in translation regulation of specific mRNA targets. Using a combination of genetic, molecular, and imaging approaches this work has identified TDP-43 induced post-transcriptional alterations in futsch and hsc70-4 mRNAs. First, futsch/MAP1B is a TDP-43 mRNA target altered at the level of mRNA localization and translation. This results in microtubule instability at the NMJ as evidenced by an increased number of satellite boutons and decreased number of Futsch positive loops that are thought to indicate stable synaptic contacts. Furthermore, overexpression of Futsch mitigates defects in microtubule stability and TDP-43 dependent locomotor dysfunction and also increases lifespan. Second, this work shows that synaptic expression of Hsc70-4, a molecular chaperone critical for synaptic vesicle cycling is involved in multiple steps of the synaptic vesicle cycle, is reduced at the NMJ when TDP-43 is overexpressed in motor neurons. Using a combination of electrophysiology and FM1-43 dye uptake assays, this work shows that motor neuron expression of TDP-43 induces defects in synaptic vesicle endocytosis. Third, this work identifies Fragile X Protein (FMRP) as a neuroprotective protein partner of TDP-43. FMRP overexpression remodels RNP granules, extracts TDP-43 from insoluble complexes, and restores the translation of specific TDP-43 targets. Together, these data provides evidence for translation dysregulation underlying microtubule instability and synaptic dysfunction in ALS pathogenesis and identifies restoration of translation via remodeling RNP granules as a neuroprotective strategy to mitigate toxicity.

<p>Amyotrophic lateral sclerosis is a progressive neurological disease which causes a slow degeneration of the body. Living with this disease means being exposed to severe strain and every day could bring new losses. Amyotrophic lateral sclerosis does not cause any harm to the intellect, the mind remains unaffected. The aim of this study was to achieve an understanding, and to shed light on the nature of positive life experiences of people living with amyotrophic lateral sclerosis. This literature study is based on detailed examination of three person's narrations taken from their autobiography and biographies. Although each person's story was different, some themes were recurring. The most powerful themes to emerge from this study was the vital importance of a sense of coherence, being able to cope, feeling hopeful, finding quality of life and engaging in good intrapersonal relationships.</p>

The selective degeneration of motoneurons in the spinal cord, the brainstem and the brain cortex is the core pathology of amyotrophic lateral sclerosis (ALS), but evidences suggest that the neighbouring non-neuronal cells are also involved in the disease progression. Beside Riluzole, only drug approved to treat this fatal neurodegenerative disease, new pharmaceutical agents or novel strategies including stem cell therapy are currently under development and evaluated preclinically in front line on mutant SOD1 rodents mimicking all hallmarks of the human disease. Current intravenously delivered drugs tested in ALS therapy assume an intact blood-brain barrier and suppose the passage across the endothelium to hit their targets in the CNS parenchyma. If BBB impairment occurs in ALS, it may lead to revision of planned pharmaceutical treatment. In the first part of the work, we have validated the mutant SOD1 rat model of ALS and we characterized properties and integrity of its BBB. We observed a significant BBB disruption at symptomatic phase of ALS, evidenced by blood protein leakage, IgG accumulation and microhemorrhage. To look for the mechanism of BBB opening, we demonstrated that the expression of key genes involved in the BBB integrity was decreased. At the ultrastructure, the morphology of endothelial cells and vascular astrocyte end-feet was altered. Our results suggest that BBB disruption is a late event in ALS disease course and appears like a consequence of the local degenerative process or neuroinflammation rather than a cause. Since a lot of extracellular oedema and swollen astrocyte end-feet were found in mutant SOD1 rats, we also looked at the expression and localization of aquaporin-4, a key protein involved in CNS water movement. We found that its expression was highly increased in the symptomatic phase of ALS course and we hypothesize that this overexpression might be related to the resolution of oedema after BBB opening. In the second part of the work, we considered an original, easy, non-invasive and safe therapeutical approach of stem cell delivery in ALS rats. Since ALS affects the motoneurons throughout the CNS, we decided to use the bloodstream to deliver neural stem cells. We studied cell homing, survival, proliferation, integration and differentiation. Interestingly, the highest efficiency of cell delivery to the CNS was found in symptomatic ALS and the lowest in healthy animals. Neural stem cells injected into ALS animals preferentially colonized the motor cortex, hippocampus and spinal cord. We detected their successful differentiation into neural lineages by the appearance of MAP2-, GFAP-positive cells and the decrease of nestin expression. One of the realistic near-term clinical goals for ALS is the transplantation of stem cells that counteract the loss of motoneurons by secreting neuroprotective factors. Accordingly, we evaluated in vitro the expression of neurotrophic factors released by stem cells after stimulation with tissue extracts from ALS rats. The aim of this paradigm was to determine whether the ALS environment triggers neuroprotective factors release from stem cells. Mesenchymal stem cells and neural stem cells were able to express a wider range of growth factors than fibroblasts. According to the stem cell population stimulated, we obtained differential expression pattern, raising the choice of cell population for appropriate clinical applications in ALS.