Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002736 (amyotrophic lateral sclerosis)
 19,048 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Neurofilaments, assembled from NF-L (68 kd), NF-M (95 kd), and NF-H (115 kd), are the most abundant structural components in large myelinated axons, particularly those of motor neurons. Aberrant neurofilament accumulation in cell bodies and axons of motor neurons is a prominent pathological feature of several motor neuron diseases, including sporadic and familial amyotrophic lateral sclerosis (ALS). Transgenic methods have proved in mice that mutation in or increased expression of neurofilament subunits can be primary causes of motor neuron disease that mimics the neurofilamentous pathology often reported in human disease. To examine whether mutation in neurofilament subunits causes or predisposes to ALS, we used single-strand conformation polymorphism coupled with DNA sequencing to search for mutations in the entirety of the human NF-L, NF-M, and NF-H genes from 100 familial ALS patients known not to carry mutations in superoxide dismutase 1 (SOD1), as well as from 75 sporadic ALS patients. Six polypeptide sequence variants were identified in rod and tail domains of NF-L, NF-M, or NF-H. However, all were found at comparable frequency in DNAs from normal individuals and no variant cosegregated with familial disease. Two deletions found previously in NF-H genes of sporadic ALS patients were not seen in this group of familial or sporadic ALS patients.
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PMID:Sequence variants in human neurofilament proteins: absence of linkage to familial amyotrophic lateral sclerosis. 887 80

Fibroblasts were cultured from 5 unrelated familial amyotrophic lateral sclerosis (FALS) patients and from healthy control subjects. In parallel, fibroblasts were examined for signs of abnormal oxidative stress by study of reactive oxygen species metabolism and, concurrently, leukocyte DNA from the same patients was examined for superoxide dismutase 1 (SOD1) mutations. The endogenous production of reactive oxygen species was assessed by following the menadione-induced reduction of oxidized cytochrome o, added to the medium. FALS and control fibroblasts exhibited the same rate of metabolism. Also levels of thiobarbturic-acid-reactive species (TBARS), a marker of lipid peroxidation, were similar in fibroblasts from either group. The search for SOD1 mutations by linkage study and cycle sequencing proved negative. We did not find evidence for SOD1 mutations by either method of study. Our results provide no evidence for increased oxidative stress in fibroblasts from non-SOD1 mutant FALS.
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PMID:Evidence against increased oxidative stress in fibroblasts from patients with non-superoxide-dismutase-1 mutant familial amyotrophic lateral sclerosis. 889 65

Transgenic mice carrying amyotrophic lateral sclerosis (ALS)-linked superoxide dismutase 1 (SOD1) mutations develop a motoneuron disease resembling human ALS. c-Jun is a transcription factor frequently induced in injured neurons. In this study we have examined the distribution of c-Jun-immunoreactivity in the brainstem and spinal cord of transgenic SOD1 mice with a glycine 93 alanine (G93A) mutation. In non-transgenic littermates c-Jun immunostaining was predominantly situated in motoneurons. The number of c-Jun immunoreactive motoneuron was reduced in SOD1(G93A) mice due to pronounced loss of motoneurons. In SOD1(G93A) mice, however, c-Jun-immunoreactivity was strongly induced in neurons in the intermediate zone (Rexed's laminae V-VIII and X) of the spinal cord and throughout the brainstem reticular formation. These findings are of interest since increased levels of c-jun also have been found in the intermediate zone of the spinal cord of ALS patients. This c-Jun may be involved in the neurodegenerative processes both in ALS and in motoneuron disease in SOD1(G93A) mice.
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PMID:Induction of c-Jun immunoreactivity in spinal cord and brainstem neurons in a transgenic mouse model for amyotrophic lateral sclerosis. 897 9

Mutations in superoxide dismutase 1 (SOD1; EC 1.15.1.1) are responsible for a proportion of familial amyotrophic lateral sclerosis (ALS) through acquisition of an as-yet-unidentified toxic property or properties. Two proposed possibilities are that toxicity may arise from imperfectly folded mutant SOD1 catalyzing the nitration of tyrosines [Beckman, J. S., Carson, M., Smith, C. D. & Koppenol, W. H. (1993) Nature (London) 364, 584] through use of peroxynitrite or from peroxidation arising from elevated production of hydroxyl radicals through use of hydrogen peroxide as a substrate [Wiedau-Pazos, M., Goto, J. J., Rabizadeh, S., Gralla, E. D., Roe, J. A., Valentine, J. S. & Bredesen, D. E. (1996) Science 271, 515-518]. To test these possibilities, levels of nitrotyrosine and markers for hydroxyl radical formation were measured in two lines of transgenic mice that develop progressive motor neuron disease from expressing human familial ALS-linked SOD1 mutation G37R. Relative to normal mice or mice expressing high levels of wild-type human SOD1, 3-nitrotyrosine levels were elevated by 2- to 3-fold in spinal cords coincident with the earliest pathological abnormalities and remained elevated in spinal cord throughout progression of disease. However, no increases in protein-bound nitrotyrosine were found during any stage of SOD1-mutant-mediated disease in mice or at end stage of sporadic or SOD1-mediated familial human ALS. When salicylate trapping of hydroxyl radicals and measurement of levels of malondialdehyde were used, there was no evidence throughout disease progression in mice for enhanced production of hydroxyl radicals or lipid peroxidation, respectively. The presence of elevated nitrotyrosine levels beginning at the earliest stages of cellular pathology and continuing throughout progression of disease demonstrates that tyrosine nitration is one in vivo aberrant property of this ALS-linked SOD1 mutant.
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PMID:Elevated free nitrotyrosine levels, but not protein-bound nitrotyrosine or hydroxyl radicals, throughout amyotrophic lateral sclerosis (ALS)-like disease implicate tyrosine nitration as an aberrant in vivo property of one familial ALS-linked superoxide dismutase 1 mutant. 920 39

Recent discoveries on linkage of the gene mutation of an enzyme, copper/zinc superoxide dismutase 1 (SOD-1), to familial amyotrophic lateral sclerosis (ALS) (which constitutes about 1% of all ALS cases) and several transgenic mouse models of ALS have shed light on potential pathogenetic processes involved in this disease. Any speculation as to the pathogenesis of ALS must reflect the unique neurobiology of motor neurons. The most distinctive aspects of motor neurons are their asymmetry, large size, and enormously elongated and thick axons. These characteristics also contribute to their vulnerability to ALS. The determinants of these unique properties are the intermediate cytoskeletal filaments, and the neurofilaments of motor neurons. This characteristic is not exclusive to motor neurons and is shared with other neurons with long axons, including some sensory neurons that are also involved in ALS. The histopathology of the early stages of ALS overwhelmingly suggests that accumulation and aggregation of neurofilaments within motor neurons is intimately related to the morphogenesis of the unique cytoplasmic inclusions, and plays a central role in the pathogenesis of the disease. Understanding of the causal relationship and the morphogenesis of inclusion bodies is critical in any attempt to reverse this complex disease process, which potentially involves the neurotoxic effects of free radicals (nitric oxide, superoxide, hydrogen peroxide, and peroxynitrite, etc) on neurofilaments. By emphasizing the unique make-up of motor neurons, this review intends to reevaluate and reinterpret the basic neuropathology of ALS in the light of recent molecular genetic-data.
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PMID:Neuropathology of amyotrophic lateral sclerosis: new perspectives on an old disease. 926 52

To clarify the pathological characteristics of astrocytic hyaline inclusions (Ast-HIs) in patients with familial amyotrophic lateral sclerosis (FALS) with neuronal Lewy-body-like hyaline inclusions (LBHIs), eight autopsies on members of four different families, including two long-term surviving patients with clinical courses of over 10 years, were analyzed. Ast-HIs were found only in the two long-term surviving patients who belonged to different families and to different races. Ast-HIs were ultrastructurally composed of 15- to 25-nm granule-coated fibrils that had immunoreactivities to superoxide dismutase 1 (SOD1) and ubiquitin. Approximately 50% of the Ast-HIs expressed alpha B-crystallin, metallothionein, glutamine synthetase, and tubulin (alpha and beta) at various intensities. Some Ast-HIs reacted with antibodies to tau protein, S-100 protein, and heat shock protein 27. The Ast-HIs were not stained for glial fibrillary acidic protein. Our results suggest a cooperative role of superoxide dismutase 1, ubiquitin, and cytoskeletal proteins in the formation of granule-coated fibrils (namely, Ast-HIs) and provide evidence that Ast-HIs are formed in certain long-surviving familial amyotrophic lateral sclerosis patients with neuronal Lewy-body-like hyaline inclusions.
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PMID:Pathological characterization of astrocytic hyaline inclusions in familial amyotrophic lateral sclerosis. 927 21

This report concerns a comparative immunocytochemical and ultrastructural investigation on pericapillary rosettes (PR) in the lumbar spinal cords of 21 patients with amyotrophic lateral sclerosis (ALS) and 18 age-matched neurologically normal individuals. The purpose of the study was to determine the alteration of PR in relation to the neuronal loss in ALS. The PR were almost always positively immunostained for phosphorylated neurofilament, and some PR immunoreacted with antibodies to synaptophysin and beta-amyloid precursor protein. This finding suggests that axonal transport, whether fast or slow, is impaired in the terminal portion of the axon that reaches the capillaries. Some PR were also positively immunostained by the antibody against ubiquitin, anti-calbindin-D 28 K antibody, anti-parvalbumin antibody and the antibody to superoxide dismutase 1. Morphometrically, the number of PR in the anterior horns and lateral column was markedly diminished in ALS compared with controls. At the ultrastructural level, the PR consisted mostly of unmyelinated degenerated axons, and were frequently found outside the basal laminae of the endothelial cell and of the astrocytic foot processes on the opposite side of the capillary, and less often in the space between the two basal laminae. The data indicate that the fate of PR is intimately associated with the neuronal loss of the anterior horn cells and with degenerative change of nerve fibers extending from their mother neurons to the capillaries.
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PMID:Immunocytochemical and ultrastructural study of pericapillary rosettes in amyotrophic lateral sclerosis. 934 34

Zinc is an important trace element in biology. An important pool of zinc in the brain is the one present in synaptic vesicles in a subgroup of glutamatergic neurons. In this form it can be released by electrical stimulation and may serve to modulate responses at receptors for a number of different neurotransmitters. These include both excitatory and inhibitory receptors, particularly the NMDA and GABA(A) receptors. This pool of zinc is the only form of zinc readily stained histochemically (the chelatable zinc pool), but constitutes only about 8% of the total zinc content in the brain. The remainder of the zinc is more or less tightly bound to proteins where it acts either as a component of the catalytic site of enzymes or in a structural capacity. The metabolism of zinc in the brain is regulated by a number of transport proteins, some of which have been recently characterized by gene cloning techniques. The intracellular concentration may be mediated both by efflux from the cell by the zinc transporter ZrT1 and by complexing with apothionein to form metallothlonein. Metallothionein may serve as the source of zinc for incorporation into proteins, including a number of DNA transcription factors. However, zinc is readily released from metallothionein by disulfides, increasing concentrations of which are formed under oxidative stress. Metallothionein is a very good scavenger of free radicals, and zinc itself can also reduce oxidative stress by binding to thiol groups, decreasing their oxidation. Zinc is also a very potent inhibitor of nitric oxide synthase. Increased levels of chelatable zinc have been shown to be present in cell cultures of immune cells undergoing apoptosis. This is very reminiscent of the zinc staining of neuronal perikarya dying after an episode of ischemia or seizure activity. Thus a possible role of zinc in causing neuronal death in the brain needs to be fully investigated. intraventricular injections of calcium EDTA have already been shown to reduce neuronal death after a period of ischemia. Pharmacological doses of zinc cause neuronal death, and some estimates indicate that extracellular concentrations of zinc could reach neurotoxic levels under pathological conditions. Zinc is released in high concentrations from the hippocampus during seizures. Unfortunately, there are contrasting observations as to whether this zinc serves to potentiate or decrease seizure activity. Zinc may have an additional role in causing death in at least some neurons damaged by seizure activity and be involved in the sprouting phenomenon which may give rise to recurrent seizure propagation in the hippocampus. In Alzheimer's disease, zinc has been shown to aggregate beta-amyloid, a form which is potentially neurotoxic. The zinc-dependent transcription factors NF-kappa B and Sp1 bind to the promoter region of the amyloid precursor protein (APP) gene. Zinc also inhibits enzymes which degrade APP to nonamyloidogenic peptides and which degrade the soluble form of beta-amyloid. The changes in zinc metabolism which occur during oxidative stress may be important in neurological diseases where oxidative stress is implicated, such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis (ALS). Zinc is a structural component of superoxide dismutase 1, mutations in which give rise to one form of familiar ALS. After HIV infection, zinc deficiency is found which may be secondary to immune-induced cytokine synthesis. Zinc is involved in the replication of the HIV virus at a number of sites. These observations should stimulate further research into the role of zinc in neuropathology.
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PMID:Zinc metabolism in the brain: relevance to human neurodegenerative disorders. 936 Dec 93

Amyotrophic lateral sclerosis (ALS) is a progressive paralytic disorder resulting from the degeneration of motor neurons in the brain and spinal cord and leading to death within 5 years of symptom onset. The great majority of ALS cases are sporadic, with the familial form (FALS) representing fewer than 10% of all cases. Mutations in the copper/zinc superoxide dismutase 1 (SOD-1) gene have previously been identified as the underlying cause of approximately 20% of FALS cases. As the familial and sporadic forms of the disease are clinically similar, we have sought to determine whether such mutations in SOD-1 underlie any sporadic ALS cases. We have screened 155 sporadic cases by single-strand conformation polymorphism and have identified 4 sporadic cases that possess point mutations in exon 4 of the SOD-1 gene. Two of these mutations are identical to those previously reported in FALS cases. One mutation is novel, resulting in a frameshift at Val118 due to the replacement of G (first base in the last codon of exon 4) by AAAAC. This mutation results in a truncated SOD-1 protein due to the introduction of a stop codon three residues into exon 5.
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PMID:Copper/zinc superoxide dismutase 1 and sporadic amyotrophic lateral sclerosis: analysis of 155 cases and identification of a novel insertion mutation. 939 81

Neurofilaments are a major component of the axonal cytoskeleton and their abnormal accumulation is a prominent feature of the cytopathology encountered in several neurodegenerative diseases. Thus, an attractive and widely held model of pathogenesis involves the participation of disrupted neurofilaments as a common toxic intermediate. Here, in direct contrast to this hypothesis, we show that two neurodegenerative disease models in the mouse, dystonia musculorum (dt) and a superoxide dismutase 1 (SOD1)-mediated form of human motor neuron disease (amyotrophic lateral sclerosis, ALS), progress with little or no abatement on a transgenic background in which neurofilaments are withheld from the axonal compartment. By specifically excluding a necessary role for axonal neurofilaments, our observations redefine the components of the pathogenic pathway leading to axon disruption in these two degenerative diseases.
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PMID:Pathogenesis of two axonopathies does not require axonal neurofilaments. 946 35


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