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Showing papers on "Amyotrophic lateral sclerosis published in 2005"


Journal ArticleDOI
TL;DR: These data confirm the presence of cognitive impairment in 50% of patients with ALS and particularly implicate executive dysfunction and mild memory decline in the disease process and have features consistent with FTD.
Abstract: Objective: To investigate the prevalence and nature of cognitive changes associated with sporadic amyotrophic lateral sclerosis (ALS) using a large scale study. Methods: Consecutive patients with sporadic ALS (n = 279) underwent comprehensive neurologic evaluation and neuropsychological testing. Testing data from normal controls (n = 129) were used for classification and comparison purposes. Results: On non-motor, non-speed-dependent tasks, 51% of patients with ALS had evidence of cognitive impairment compared to 5% of controls. Cluster analysis suggested four patient subgroups: 49% intact, 32% with mild impairment, 13% with moderate impairment, and 6% with severe impairment. Forty-one patients (15%) met criteria for frontotemporal dementia (FTD). ALS patient subgroups, excluding the intact group, performed significantly lower on tests of executive function and memory than normal controls. Patients with more severe disease also had deficits in confrontation naming. Although memory function declined with increasing severity of overall cognitive impairment, only two patients had the severe memory loss typical of Alzheimer disease. Cognitive impairment was correlated with clinical measures of word-finding, phrase length, and motor programming. Cognitive impairment was not correlated with depression scores or severity or duration of motor or bulbar symptoms. Patients with bulbar vs limb-onset ALS were not different in either level of impairment or pattern of performance. Conclusions: These data confirm the presence of cognitive impairment in 50% of patients with ALS and particularly implicate executive dysfunction and mild memory decline in the disease process. More severe impairment occurs in a subset of patients with ALS and has features consistent with FTD.

788 citations


Journal ArticleDOI
TL;DR: This review draws together and summarize information from many laboratories about the characteristics of the individual mutant SOD1 proteins in vivo and in vitro in the hope that it will aid investigators in their search for the cause(s) of S OD1-associated fALS.
Abstract: Copper-zinc superoxide dismutase (CuZnSOD, SOD1 protein) is an abundant copper- and zinc-containing protein that is present in the cytosol, nucleus, peroxisomes, and mitochondrial intermembrane space of human cells. Its primary function is to act as an antioxidant enzyme, lowering the steady-state concentration of superoxide, but when mutated, it can also cause disease. Over 100 different mutations have been identified in the sod1 genes of patients diagnosed with the familial form of amyotrophic lateral sclerosis (fALS). These mutations result in a highly diverse group of mutant proteins, some of them very similar to and others enormously different from wild-type SOD1. Despite their differences in properties, each member of this diverse set of mutant proteins causes the same clinical disease, presenting a challenge in formulating hypotheses as to what causes SOD1-associated fALS. In this review, we draw together and summarize information from many laboratories about the characteristics of the individual mutant SOD1 proteins in vivo and in vitro in the hope that it will aid investigators in their search for the cause(s) of SOD1-associated fALS.

681 citations


Journal ArticleDOI
TL;DR: These data are the first to show a substantial extension of survival in an animal model of a fatal, dominantly inherited neurodegenerative condition using RNAi and provide the highest therapeutic efficacy observed in this field to date.
Abstract: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease resulting in the selective death of motor neurons in the brain and spinal cord. Some familial cases of ALS are caused by dominant mutations in the gene encoding superoxide dismutase (SOD1). The emergence of interfering RNA (RNAi) for specific gene silencing could be therapeutically beneficial for the treatment of such dominantly inherited diseases. We generated a lentiviral vector to mediate expression of RNAi molecules specifically targeting the human SOD1 gene (SOD1). Injection of this vector into various muscle groups of mice engineered to overexpress a mutated form of human SOD1 (SOD1(G93A)) resulted in an efficient and specific reduction of SOD1 expression and improved survival of vulnerable motor neurons in the brainstem and spinal cord. Furthermore, SOD1 silencing mediated an improved motor performance in these animals, resulting in a considerable delay in the onset of ALS symptoms by more than 100% and an extension in survival by nearly 80% of their normal life span. These data are the first to show a substantial extension of survival in an animal model of a fatal, dominantly inherited neurodegenerative condition using RNAi and provide the highest therapeutic efficacy observed in this field to date.

537 citations


Journal ArticleDOI
TL;DR: It is reported that in SOD1G93A transgenic mice, a model for familial ALS, intraspinal injection of a lentiviral vector that produces RNAi-mediated silencing of S OD1 substantially retards both the onset and the progression rate of the disease.
Abstract: Mutations in Cu/Zn superoxide dismutase (encoded by SOD1), one of the causes of familial amyotrophic lateral sclerosis (ALS), lead to progressive death of motoneurons through a gain-of-function mechanism. RNA interference (RNAi) mediated by viral vectors allows for long-term reduction in gene expression and represents an attractive therapeutic approach for genetic diseases characterized by acquired toxic properties. We report that in SOD1(G93A) transgenic mice, a model for familial ALS, intraspinal injection of a lentiviral vector that produces RNAi-mediated silencing of SOD1 substantially retards both the onset and the progression rate of the disease.

488 citations


Journal ArticleDOI
TL;DR: In this article, muscle-restricted expression of localized insulin-like growth factor (Igf) -1 isoform maintained muscle integrity and enhanced satellite cell activity in SOD1G93A transgenic mice, inducing calcineurin-mediated regenerative pathways.
Abstract: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by a selective degeneration of motor neurons, atrophy, and paralysis of skeletal muscle. Although a significant proportion of familial ALS results from a toxic gain of function associated with dominant SOD1 mutations, the etiology of the disease and its specific cellular origins have remained difficult to define. Here, we show that muscle-restricted expression of a localized insulin-like growth factor (Igf) -1 isoform maintained muscle integrity and enhanced satellite cell activity in SOD1G93A transgenic mice, inducing calcineurin-mediated regenerative pathways. Muscle-specific expression of local Igf-1 (mIgf-1) isoform also stabilized neuromuscular junctions, reduced inflammation in the spinal cord, and enhanced motor neuronal survival in SOD1G93A mice, delaying the onset and progression of the disease. These studies establish skeletal muscle as a primary target for the dominant action of inherited SOD1 mutation and suggest that muscle fibers provide appropriate factors, such as mIgf-1, for neuron survival.

337 citations


Journal ArticleDOI
TL;DR: There is new evidence that non-neuronal cells in the vicinity of motor neurones may contribute to neuronal injury and the final demise ofMotor neurones is likely to involve a programmed cell death pathway resembling apoptosis.
Abstract: The process of neuronal degeneration in motor neurone disease is complex. Several genetic alterations may be involved in motor neurone injury in familial amyotrophic lateral sclerosis, less is known about the genetic and environmental factors involved in the commoner sporadic form of the disease. Most is known about the mechanisms of motor neurone degeneration in the subtype of disease caused by SOD1 mutations, but even here there appears to be a complex interplay between multiple pathogenic processes including oxidative stress, protein aggregation, mitochondrial dysfunction excitotoxicity, and impaired axonal transport. There is new evidence that non-neuronal cells in the vicinity of motor neurones may contribute to neuronal injury. The final demise of motor neurones is likely to involve a programmed cell death pathway resembling apoptosis.

318 citations


Journal ArticleDOI
TL;DR: It is proposed that impaired axonal transport is a prime cause of neuronal death in neurodegenerative disorders such as ALS and crossing S OD1G93A mice with Loa/+ mice delays disease progression and significantly increases life span in Loa/SOD1G 93A mice.
Abstract: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative condition characterized by motoneuron degeneration and muscle paralysis. Although the precise pathogenesis of ALS remains unclear, mutations in Cu/Zn superoxide dismutase (SOD1) account for ~20–25% of familial ALS cases, and transgenic mice overexpressing human mutant SOD1 develop an ALS-like phenotype. Evidence suggests that defects in axonal transport play an important role in neurodegeneration. In Legs at odd angles (Loa) mice, mutations in the motor protein dynein are associated with axonal transport defects and motoneuron degeneration. Here, we show that retrograde axonal transport defects are already present in motoneurons of SOD1G93A mice during embryonic development. Surprisingly, crossing SOD1G93A mice with Loa/+ mice delays disease progression and significantly increases life span in Loa/SOD1G93A mice. Moreover, there is a complete recovery in axonal transport deficits in motoneurons of these mice, which may be responsible for the amelioration of disease. We propose that impaired axonal transport is a prime cause of neuronal death in neurodegenerative disorders such as ALS.

255 citations


Journal ArticleDOI
TL;DR: High‐resolution in vivo imaging in the G93A SOD1 mouse model showed that degenerative axon branches are easily distinguished from those undergoing compensatory reinnervation, showing fragmentation of terminal branches but sparing of the more proximal axon.
Abstract: Amyotrophic lateral sclerosis is a fatal paralytic disease that targets motor neurons, leading to motor neuron death and widespread denervation atrophy of muscle. Previous electrophysiological data have shown that some motor axon branches attempt to compensate for loss of innervation, resulting in enlarged axonal arbors. Recent histological assays have shown that during the course of the disease some axonal branches die back. We thus asked whether the two types of behavior, die-back and compensatory growth, occur in different branches of single neurons or, alternatively, whether entire motor units are of one type or the other. We used high-resolution in vivo imaging in the G93A SOD1 mouse model, bred to express transgenic yellow fluorescent protein in all or subsets of motor neurons. Time-lapse imaging showed that degenerative axon branches are easily distinguished from those undergoing compensatory reinnervation, showing fragmentation of terminal branches but sparing of the more proximal axon. Reconstruction of entire motor units showed that some were abnormally large. Surprisingly, these large motor units contained few if any degenerating synapses. Some small motor units, however, no longer possessed any neuromuscular contacts at all, giving the appearance of "winter trees." Thus, degenerative versus regenerative changes are largely confined to distinct populations of neurons within the same motor pool. Identification of factors that protect "compensatory" motor neurons from degenerative changes may provide new targets for therapeutic intervention.

255 citations


Journal ArticleDOI
TL;DR: A common pattern of gray matter atrophy was seen in both ALS and ALS/FTLD patients when compared to controls, which supports the idea of a clinical and anatomic continuum between ALS and frontotemporal lobar degeneration.
Abstract: Objective: To investigate the patterns of MRI brain atrophy in patients with ALS with and without clinically evident frontotemporal lobar dementia (FTLD) using voxel-based morphometry (VBM). Methods: Voxel-based morphometry was used to compare T1-weighted MRI images obtained from ten ALS patients with FTLD, ten ALS patients who were cognitively and behaviorally normal, and 22 control subjects. Images from patients and controls were spatially pre-processed using a study-specific, customized template and a priori images. A statistical threshold of p Results: A common pattern of gray matter atrophy was seen in both ALS and ALS/FTLD patients when compared to controls that involved the bilateral motor/premotor cortices, the left middle and inferior frontal gyri, the anterior portion of the superior frontal gyri, the superior temporal gyri, the temporal poles and left posterior thalamus. Most of the frontal regions were significantly more atrophied in the ALS/FTLD group than in the ALS group. No significant differences were found in white matter volumes. Conclusions: Patients with ALS and ALS associated with frontotemporal lobar degeneration exhibit widespread gray matter atrophy in frontotemporal regions. This finding supports the idea of a clinical and anatomic continuum between ALS and frontotemporal lobar degeneration.

251 citations


Journal ArticleDOI
TL;DR: The motor neuron–specific gene expression profile in sporadic ALS can provide direct information on the genes leading to neurodegeneration and neuronal death and are helpful for developing new therapeutic strategies.
Abstract: The causative pathomechanism of sporadic amyotrophic lateral sclerosis (ALS) is not clearly understood. Using microarray technology combined with laser-captured microdissection, gene expression profiles of degenerating spinal motor neurons isolated from autopsied patients with sporadic ALS were examined. Gene expression was quantitatively assessed by real-time reverse transcription polymerase chain reaction and in situ hybridization. Spinal motor neurons showed a distinct gene expression profile from the whole spinal ventral horn. Three percent of genes examined were downregulated, and 1% were upregulated in motor neurons. Downregulated genes included those associated with cytoskeleton/axonal transport, transcription, and cell surface antigens/receptors, such as dynactin, microtubule-associated proteins, and early growth response 3 (EGR3). In contrast, cell death-associated genes were mostly upregulated. Promoters for cell death pathway, death receptor 5, cyclins A1 and C, and caspases-1, -3, and -9, were upregulated, whereas cell death inhibitors, acetyl-CoA transporter, and NF-kappaB were also upregulated. Moreover, neuroprotective neurotrophic factors such as ciliary neurotrophic factor (CNTF), Hepatocyte growth factor (HGF), and glial cell line-derived neurotrophic factor were upregulated. Inflammation-related genes, such as those belonging to the cytokine family, were not, however, significantly upregulated in either motor neurons or ventral horns. The motor neuron-specific gene expression profile in sporadic ALS can provide direct information on the genes leading to neurodegeneration and neuronal death and are helpful for developing new therapeutic strategies.

243 citations


Journal ArticleDOI
TL;DR: The hypothesis of a continuum of extra–motor cerebral and cognitive change in ALS patients with no evidence of cognitive change is supported, and structural white matter abnormalities in frontal and temporal regions revealed here may underlie the cognitive and functional imaging abnormalities previously reported in non–demented ALS patients.
Abstract: Cognitive dysfunction can occur in some patients with amyotrophic lateral sclerosis (ALS) who are not suffering from dementia. The most striking and consistent cognitive deficit has been found using tests of verbal fluency. ALS patients with verbal fluency deficits have shown functional imaging abnormalities predominantly in frontotemporal regions using positron emission tomography (PET). This study used automated volumetric voxel-based analysis of grey and white matter densities of structural magnetic resonance imaging (MRI) scans to explore the underlying pattern of structural cerebral change in nondemented ALS patients with verbal fluency deficits. Two groups of ALS patients, defined by the presence or absence of cognitive impairment on the basis of the Written Verbal Fluency Test (ALSi, cognitively impaired, n = 11; ALSu, cognitively unimpaired n = 12) were compared with healthy age matched controls (n = 12). A comparison of the ALSi group with controls revealed significantly (p < 0.002) reduced white matter volume in extensive motor and non–motor regions, including regions corresponding to frontotemporal association fibres. These patients demonstrated a corresponding cognitive profile of executive and memory dysfunction. Less extensive white matter reductions were revealed in the comparison of the ALSu and control groups in regions corresponding to frontal association fibres. White matter volumes were also found to correlate with performance on memory tests. There were no significant reductions in grey matter volume in the comparison of either patient group with controls. The structural white matter abnormalities in frontal and temporal regions revealed here may underlie the cognitive and functional imaging abnormalities previously reported in non–demented ALS patients. The results also suggest that extra–motor structural abnormalities may be present in ALS patients with no evidence of cognitive change. The findings support the hypothesis of a continuum of extra–motor cerebral and cognitive change in this disorder.

Journal ArticleDOI
TL;DR: Pio-treated transgenic mice revealed improved muscle strength and body weight, exhibited a delayed disease onset, and survived significantly longer than nontreated SOD1-G93A mice, indicating not only morphological but also functional protection of motor neurons by Pio.
Abstract: Amyotrophic lateral sclerosis (ALS) represents a fatal neurodegenerative disorder characterized by progressive death of the upper and lower motor neurons. Because accompanying inflammation may interact with and promote neurodegeneration, anti-inflammatory treatment strategies are being evaluated. Because peroxisome proliferator-activated receptor gamma (PPARgamma) agonists act as potent anti-inflammatory drugs, we tested whether superoxide dismutase (SOD1)-G93A transgenic mice, a mouse model of ALS, benefit from oral treatment with the PPARgamma agonist pioglitazone (Pio). Pio-treated transgenic mice revealed improved muscle strength and body weight, exhibited a delayed disease onset, and survived significantly longer than nontreated SOD1-G93A mice. Quantification of motor neurons of the spinal cord at day 90 revealed complete neuroprotection by Pio, whereas nontreated SOD1-G93A mice had lost 30% of motor neurons. This was paralleled by preservation of the median fiber diameter of the quadriceps muscle, indicating not only morphological but also functional protection of motor neurons by Pio. Activated microglia were significantly reduced at sites of neurodegeneration in Pio-treated SOD1-G93A mice, as were the protein levels of cyclooxygenase 2 and inducible nitric oxide synthase. Interestingly, mRNA levels of the suppressor of cytokine signaling 1 and 3 genes were increased by Pio, whereas both the mRNA and protein levels of endogenous mouse SOD1 and of transgenic human SOD1 remained unaffected.

Journal ArticleDOI
01 Sep 2005-Glia
TL;DR: This review integrates the current knowledge of the role of microglia in an adult‐onset neurodegenerative disease, amyotrophic lateral sclerosis (ALS), and pays particular attention to the possible mechanisms of initiation and propagation of neuronal damage during disease onset and progression.
Abstract: The central nervous system (CNS) is equipped with a variety of cell types, all of which are assigned particular roles during the development, maintenance, function and repair of neural tissue. One glial cell type, microglia, deserves particular attention, as its role in the healthy or injured CNS is incompletely understood. Evidence exists for both regenerative and degenerative functions of these glial cells during neuronal injury. This review integrates the current knowledge of the role of microglia in an adult-onset neurodegenerative disease, amyotrophic lateral sclerosis (ALS), and pays particular attention to the possible mechanisms of initiation and propagation of neuronal damage during disease onset and progression. Microglial cell properties, behavior and detected inflammatory reactions during the course of the disease are described. The neuroinflammatory changes that occur in a mouse model of ALS are summarized. The understanding of microglial function in the healthy and injured CNS could offer better diagnostic as well as therapeutic approaches for prevention, retardation, or repair of neural tissue degeneration.

Journal ArticleDOI
TL;DR: The evidence that suggests that somatotopically specific patterns of altered kinase and phosphatase activity are associated with alterations in the phosphorylation state of these proteins, altering either solubility or assembly characteristics is reviewed.
Abstract: Amyotrophic lateral sclerosis (ALS) is increasingly considered to be a disorder of multiple etiologies that have in common progressive degeneration of both upper and lower motor neurons, ultimately giving rise to a relentless loss of muscle function. This progressive degeneration is associated with heightened levels of oxidative injury, excitotoxicity, and mitochondrial dysfunction-all occurring concurrently. In this article, we review the evidence that suggests, in common with other age-dependent neurodegenerative disorders, that ALS can be considered a disorder of protein aggregation. Morphologically, this is evident as Bunina bodies, ubiquitin-immunoreactive fibrils or aggregates, neurofilamentous aggregates, mutant copper/zinc superoxide dismutase (SOD1) aggregates in familial ALS variants harboring mutations in SOD 1, peripherin-immunoreactive aggregates within spinal motor neurons and as neuroaxonal spheroids, and in an increasingly greater population of patients with ALS with cognitive impairment, both intra- and extraneuronal tau aggregates. We review the evidence that somatotopically specific patterns of altered kinase and phosphatase activity are associated with alterations in the phosphorylation state of these proteins, altering either solubility or assembly characteristics. The role of nonneuronal cells in mediating motor neuronal injury is discussed in the context of alterations in tyrosine kinase activity and enhanced protein phosphorylation.

Journal ArticleDOI
TL;DR: Detailed studies in transgenic mouse models of familial ALS expressing mutant Cu, Zn superoxide dismutase (SOD1) indicate that mitochondrial abnormalities begin prior to the clinical and pathological onset of the disease, suggesting that mitochondrial dysfunction may be causally involved in the pathogenesis of ALS.

Journal ArticleDOI
TL;DR: Celastrol has been widely used in treating inflammatory diseases in man, and is well tolerated; therefore, it may be a promising therapeutic candidate for the treatment of human ALS.
Abstract: There is substantial evidence that both inflammation and oxidative damage contribute to the pathogenesis of motor neuron degeneration in the G93A SOD1 transgenic mouse model of amyotrophic lateral sclerosis (ALS). Celastrol is a natural product from Southern China, which exerts potent anti-inflammatory and antioxidative effects. It also acts potently to increase expression of heat shock proteins including HSP70. We administered it in the diet to G93A SOD1 mice starting at 30 days of age. Celastrol treatment significantly improved weight loss, motor performance and delayed the onset of ALS. Survival of celastrol-treated G93A mice increased by 9.4% and 13% for 2 mg/kg/day and 8 mg/kg/day doses, respectively. Cell counts of lumbar spinal cord neurons confirmed a protective effect, i.e. 30% increase in neuronal number in the lumbar spinal cords of celastrol-treated animals. Celastrol treatment reduced TNF-alpha, iNOS, CD40, and GFAP immunoreactivity in the lumbar spinal cord sections of celastrol-treated G93A mice compared to untreated G93A mice. TNF-alpha immunoreactivity co-localized with SMI-32 (neuronal marker) and GFAP (astrocyte marker). HSP70 immunoreactivity was increased in lumbar spinal cord neurons of celastrol-treated G93A mice. Celastrol has been widely used in treating inflammatory diseases in man, and is well tolerated; therefore, it may be a promising therapeutic candidate for the treatment of human ALS.

Journal ArticleDOI
TL;DR: The R1101K sequence alteration of the DCTN1 gene may predispose subjects to ALS and FTD and the involved genes for copper/zinc superoxide dismutase (SOD1) and tau were excluded.
Abstract: A heterozygous R1101K mutation of the p150 subunit of dynactin (DCTN1) is reported in a family with amyotrophic lateral sclerosis (ALS) and co-occurrence of frontotemporal dementia (FTD). Two members of our kindred were affected with motor neuron disease and two with dementia in an autosomal dominant pattern of inheritance. We excluded the involvement of the ALS and FTD-linked genes for copper/zinc superoxide dismutase (SOD1) and tau. The R1101K sequence alteration of the DCTN1 gene may predispose subjects to ALS and FTD.

Journal ArticleDOI
TL;DR: This article performed a longitudinal study of frontal and temporal lobe functions in patients with amyotrophic lateral sclerosis (ALS) and compared the evolution of cognitive performance with that of motor deficits in patients having spinal and bulbar onset of the disease.
Abstract: We performed a longitudinal study of frontal and temporal lobe functions in patients with amyotrophic lateral sclerosis (ALS) and compared the evolution of cognitive performance with that of motor deficits in patients with spinal and bulbar-onset of the disease. Fifty two patients suffering from sporadic ALS according to the El Escorial criteria were examined; 37 patients had a spinal, 15 a bulbar onset of the disease. The data profile included examinations at entry (E1), every four months at follow-up (E2, E3, E4) and after 18 months (E5), if possible. Neuropsychological testing covered the domains of executive functions, memory and attentional control. ALS patients showed executive dysfunctions that were most prominently represented by deficits of non-verbal and verbal fluency and concept formation. Memory-related deficits were also present but less expressed. The same held true for phasic and tonic alertness and divided attention. In contrast to motor functions declining concomitantly with disease progression, cognitive deficits appeared in early disease, were essentially present at initial testing and did not substantially decline on follow-up. A subgroup analysis revealed that bulbar-onset ALS patients performed consistently poorer in many cognitive tests than spinal-onset ones with special reference to verbal and non-verbal fluency and interference control. This subgroup difference persisted or even increased throughout follow-up. We conclude that there is a fronto-temporal pattern of cognitive dysfunction in ALS expressing itself early in the course of the disease and mainly with bulbar forms. The cognitive deficits do not progress in synchrony with motor decline, but distinctly more slowly. We suggest that cognitive dysfunctions reflect functional and possibly morphological deficits outside the primary motor system that is specific for the nature and evolution of the disease and might also give clues to etiopathogenesis.

Journal ArticleDOI
TL;DR: The intrinsic properties of motor neurons that render these cells particularly vulnerable to excitotoxicity and could explain the selective vulnerability ofMotor neurons in ALS are summarized to help to develop new and better therapeutic strategies that could protect motor neurons from excitOToxicity.
Abstract: Since its description by Charcot more than 130 years ago, the pathogenesis of selective motor neuron degeneration in amyotrophic lateral sclerosis (ALS) remains unsolved. Over the years, many pathogenic mechanisms have been proposed. Amongst others these include: oxidative stress, excitotoxicity, aggregate formation, inflammation, growth factor deficiency and neurofilament disorganization. This multitude of contributing factors indicates that ALS is a complex disease and also suggests that ALS is a multifactorial disorder. Excitotoxicity is not the newest and most spectacular hypothesis in the ALS field, but it is undoubtedly one of the most robust pathogenic mechanisms supported by an impressive amount of evidence. Moreover, the therapeutic efficacy of riluzole, the only drug proven to slow disease progression in ALS, is most likely related to its anti-excitotoxic properties. In this review, we will give an overview of the arguments in favor of the involvement of excitotoxicity in ALS and of the possible mechanisms leading to motor neuron death. We will also summarize the intrinsic properties of motor neurons that render these cells particularly vulnerable to excitotoxicity and could explain the selective vulnerability of motor neurons in ALS. All this information could help to develop new and better therapeutic strategies that could protect motor neurons from excitotoxicity.

Journal ArticleDOI
TL;DR: A family from southern Italy with three brothers affected by early‐onset parkinsonism, dementia, and amyotrophic lateral sclerosis is reported, expanding the spectrum of clinical presentations associated with mutations in DJ‐1 gene.
Abstract: DJ-1 gene mutations have been found to cause early-onset Parkinson's disease. We report a family from southern Italy with three brothers affected by early-onset parkinsonism, dementia, and amyotrophic lateral sclerosis. Molecular analysis of the DJ-1 gene in two living patients showed a novel homozygous mutation in exon 7 (E163K) and a new homozygous mutation (g.168_185dup) in the promoter region of the gene. Both mutations cosegregated with the disease and were detected in a heterozygous state in the patients' mother and their healthy siblings. Our findings expand the spectrum of clinical presentations associated with mutations in DJ-1 gene.

Journal ArticleDOI
TL;DR: Male mice with inactivated liver X receptor (LXR) beta suffer from adult-onset motor neuron degeneration and it is speculated that absence of LXRbeta leads to pathological accumulation of sterols and lipids that may themselves be neurotoxic or may modulate intracellular pathways and thereby predispose motor neurons to degeneration.
Abstract: Male mice with inactivated liver X receptor (LXR) β suffer from adult-onset motor neuron degeneration. By 7 months of age, motor coordination is impaired, and this condition is associated with lipid accumulation and loss of motor neurons in the spinal cord, together with axonal atrophy and astrogliosis. Several of these features are reminiscent of the neuropathological signs of chronic motor neuron disease such as amyotrophic lateral sclerosis. Because the LXRs are important for cholesterol and lipid metabolism, we speculate that absence of LXRβ leads to pathological accumulation of sterols and lipids that may themselves be neurotoxic or may modulate intracellular pathways and thereby predispose motor neurons to degeneration.

Journal ArticleDOI
TL;DR: Results suggest that metabolomic studies can be used to ascertain metabolic signatures of disease in a non-invasive fashion and should provide insight into aberrant biochemical pathways and may provide diagnostic markers and targets for drug design.
Abstract: Motor neuron diseases (MND) are a heterogeneous group of disorders that includes amyotrophic lateral sclerosis (ALS) and result in death of motor neurons. These diseases may produce characteristic perturbations of the metabolome, the collection of smallmolecules (metabolites) present in a cell, tissue, or organism. To test this hypothesis, we used high performance liquid chromatography followed by electrochemical detection to profile blood plasma from 28 patients with MND and 30 healthy controls. Of 317 metabolites, 50 were elevated in MND patients and more than 70 were decreased (p<0.05). Among the compounds elevated, 12 were associated with the drug Riluzole. In a subsequent study of 19 subjects with MND who were not taking Riluzole and 33 healthy control subjects, six compounds were significantly elevated in MND, while the number of compounds with decreased concentration was similar to study 1. Our data also revealed a distinctive signature of highly correlated metabolites in a set of four patients, three of whom had lower motor neuron (LMN) disease. In both datasets we were able to separate MND patients from controls using multivariate regression techniques. These results suggest that metabolomic studies can be used to ascertain metabolic signatures of disease in a non-invasive fashion. Elucidation of the structures of signature molecules in ALS and other forms of MND should provide insight into aberrant biochemical pathways and may provide diagnostic markers and targets for drug design.

Journal ArticleDOI
TL;DR: The variety of morphologies and the anatomic distribution of ub-ir pathology to be greater than previously documented and the degree of overlap suggests that MND, MND-d, and FTD-MND type represent a spectrum of clinical disease with a common pathologic substrate.
Abstract: One of the characteristic pathologic changes in classic motor neuron disease (MND) is the presence of ubiquitin-immunoreactive (ub-ir) inclusions in the cytoplasm of lower motor neurons. In addition, cases of MND with dementia (MND-d) also have ub-ir neuronal cytoplasmic inclusions and dystrophic neurites in extramotor neocortex and hippocampus. Although this extramotor pathology is a highly sensitive marker for dementia in MND, similar changes are found in a subset of patients with frontotemporal dementia (FTD) with no motor symptoms (FTD-MND type). The purpose of this study is to more fully describe and compare the pattern of ub-ir pathology in these 3 conditions. We performed ubiquitin immunohistochemistry on postmortem tissue, representing a wide range of neuroanatomic structures, in cases of classic MND (n = 20), MND-d (n = 15), and FTD-MND type (n = 15). We found the variety of morphologies and the anatomic distribution of ub-ir pathology to be greater than previously documented. Moreover, the degree of overlap suggests that MND, MND-d, and FTD-MND type represent a spectrum of clinical disease with a common pathologic substrate. The only finding restricted to a specific subgroup of patients was the presence of ub-ir neuronal intranuclear inclusions in some cases of familial FTD.


Journal ArticleDOI
TL;DR: In this article, the degree of activation was directly related to the rate of sALS disease progression and other parameters of T-cell activation and immune globulin levels showed similar disease associated changes.

Journal ArticleDOI
TL;DR: The role of oxidative stress as a major mechanism in the pathogenesis of ALS is supported and structural alteration and activity decline of functional proteins may consistently contribute to the neurodegeneration process in ALS.

Journal ArticleDOI
TL;DR: Investigation of neurotracer transport from muscle to motor neuron in a transgenic mouse model of amyotrophic lateral sclerosis suggested inhibition of dynein/dynactin function may have a role in motor neuron degeneration in amyotroph lateral sclerosis.
Abstract: Cytoplasmic dynein and dynactin drive retrograde axonal transport in neurons, and mutations in dynein/dynactin cause motor neuron degeneration. To test whether defects in dynein/dynactin function are involved in the neurodegenerative disease amyotrophic lateral sclerosis, we examined neurotracer transport from muscle to motor neuron in a transgenic mouse model of amyotrophic lateral sclerosis. Significant inhibition was observed, which was temporally correlated with declines in muscle strength. No decrease in dynein/dynactin expression was observed, but immunohistochemistry suggests that dynein associates with aggregates of mutant Cu/Zn superoxide dismutase 1. Expression of mutant Cu/Zn superoxide dismutase 1 in primary motor neurons altered the cellular localization of dynein, suggesting an inhibition of dynein/dynactin function. Thus, inhibition of dynein/dynactin function may have a role in motor neuron degeneration in amyotrophic lateral sclerosis.

Journal ArticleDOI
01 Jun 2005-Brain
TL;DR: This study provides evidence for differences in the distribution of reduced cortical [11C]flumazenil binding in homD90A compared with sALS patients and hypothesize that this might reflect differences in cortical neuronal vulnerability.
Abstract: Five to ten percent of amyotrophic lateral sclerosis (ALS) cases are associated with mutations of the superoxide dismutase-1 (SOD1) gene, and the 'D90A' mutation is associated with a unique phenotype and markedly slower disease progression (mean survival time 14 years). Relative sparing of inhibitory cortical neuronal circuits might be one mechanism contributing to the slower progression in patients homozygous for the D90A mutation (homD90A). The GABA(A) receptor PET ligand [11C]flumazenil has demonstrated motor and extra-motor cortical changes in sporadic ALS. In this study, we used [11C]flumazenil PET to explore differences in the pattern of cortical involvement between sporadic and genetically homogeneous ALS groups. Twenty-four sporadic ALS (sALS) and 10 homD90A patients underwent [11C]flumazenil PET of the brain. In addition, two subjects homozygous for the D90A mutation, but without symptoms or signs ('pre-symptomatic', psD90A), also underwent imaging. Results for each group were compared with those for 24 healthy controls of similar age. Decreases in the binding of [11C]flumazenil in the sALS group were found within premotor regions, motor cortex and posterior motor association areas. In the homD90A group of ALS patients, however, decreases were concentrated in the left fronto-temporal junction and anterior cingulate gyrus. In the two psD90A subjects, a small focus of reduced [11C]flumazenil binding at the left fronto-temporal junction was seen, similar to the pattern seen in the clinically affected patients. Within the sALS group, there was no statistically significant association between decreases in cortical [11C]flumazenil binding and revised ALS functional rating scale (ALSFRS-R score), whereas the upper motor neuron (UMN) score correlated with widespread and marked cortical decreases over the dominant hemisphere. In the homD90A group, there was a stronger statistical association between reduced cortical [11C]flumazenil binding and the ALSFRS-R, rather than the UMN, score, and also with disease duration. This study provides evidence for differences in the distribution of reduced cortical [11C]flumazenil binding in homD90A compared with sALS patients. We hypothesize that this might reflect differences in cortical neuronal vulnerability.

Journal ArticleDOI
01 Jun 2005-Chest
TL;DR: In this paper, the impact of early respiratory evaluation of home mechanical ventilation (HMV) indications for patients with amyotrophic lateral sclerosis (ALS) on the survival of patients receiving noninvasive ventilation (NIV) was analyzed.

Journal ArticleDOI
TL;DR: Results show that the catalytic antioxidant AEOL 10150 provides a pronounced therapeutic benefit with onset administration and is, therefore, a promising agent for the treatment of ALS.
Abstract: Mice that overexpress the human Cu,Zn superoxide dismutase-1 mutant G93A develop a delayed and progressive motor neuron disease similar to human amyotrophic lateral sclerosis (ALS). Most current studies of therapeutics in these mice to date have involved administration of agents long before onset of symptoms, which cannot currently be accomplished in human ALS patients. We examined the effects of the manganese porphyrin AEOL 10150 (manganese [III] tetrakis[N-N'-diethylimidazolium-2-yl]porphyrin) given at symptom onset and found, in three separate studies, that it extended the survival after onset up to 3.0-fold. Immunohistochemical analysis of spinal cord for SMI-32, an abundant protein in motor neurons, indicated better preservation of motor neuron architecture, less astrogliosis (glial fibrillary acidic protein), and markedly less nitrotyrosine and malondialdehyde in porphyrin-treated spinal cords relative to vehicle-treated mice. These results show that the catalytic antioxidant AEOL 10150 provides a pronounced therapeutic benefit with onset administration and is, therefore, a promising agent for the treatment of ALS.