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)

Seeds of the Guam cycad Cycas micronesica K.D. Hill (Cycadaceae), which contain ss-methylamino-L-alanine (BMAA), have been implicated in the etiology of the devastating neurodisease ALS-PDC that is found among the native Chamorros on Guam. The disease also occurs in the native populations on Irian Jaya and the Kii Peninsula of Japan, and in all three areas the cycad seeds are used either dietarily or medically. ALS-PDC is a complex of amyotrophic lateral sclerosis and parkinsonism dementia complex with additional symptoms of Alzheimer's. It is well known that Ca(2+) elevations in brain cells can lead to cell death and neurodiseases. Therefore, we evaluated the ability of the cycad toxin BMAA to elevate the intracellular calcium concentration ([Ca(2+)](i)) in dissociated newborn rat brain cells loaded with fura-2 dye. BMAA produced an increase in intracellular calcium levels in a concentration-dependent manner. The increases were dependent not only on extracellular calcium concentrations, but also significantly on the presence of bicarbonate ion. Increasing concentrations of sodium bicarbonate resulted in a potentiation of the BMAA-induced [Ca(2+)](i) elevation. The bicarbonate dependence did not result from the increased sodium concentration or alkalinization of the buffer. Our results support the hypothesis that the neurotoxicity of BMAA is due to an excitotoxic mechanism, involving elevated intracellular calcium levels and bicarbonate. Furthermore, since BMAA alone produced no increase in Ca(2+) levels, these results suggest the involvement of a product of BMAA and CO(2), namely a beta-carbamate, which has a structure similar to other excitatory amino acids (EAA) such as glutamate; thus, the causative agent for ALS-PDC on Guam and elsewhere may be the beta-carbamate of BMAA. These findings support the theory that some forms of other neurodiseases may also involve environmental toxins.
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PMID:The cycad neurotoxic amino acid, beta-N-methylamino-L-alanine (BMAA), elevates intracellular calcium levels in dissociated rat brain cells. 1224 91

In the 1950s, the incidence of amyotrophic lateral sclerosis (ALS, or Lytico) and parkinsonism-dementia complex (PDC, or Bodig) on the island of Guam was much higher than anywhere else in the world. From the late 1960s to the early 1980s, the incidence of both disorders has decreased. The objective of the present study was to ascertain whether the decreasing incidence continued until the end of the century (1999). The average annual incidence of ALS and PDC was calculated for each 5-year period from 1940 to 1999, utilizing registration records of all ALS and PDC cases on Guam during that period. The results of this study confirmed that the incidence of ALS declined steadily during the past 40 years. The incidence of PDC also declined until the late 1980s but, unlike ALS, showed a slight increase from 1980 to 1999. The rapid decrease in incidence is not likely to be due to genetic factors. Instead, it is most likely to be the results of radical socioeconomic, ethnographic, and ecologic changes brought about by the rapid westernization of Guam.
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PMID:Amyotrophic lateral sclerosis and parkinsonism-dementia complex of Guam: changing incidence rates during the past 60 years. 1252 22

This report concerns a Japanese family with neuropathological findings consistent with amyotrophic lateral sclerosis/parkinsonism-dementia complex (ALS/PDC) in the Island of Guam. The proband was a 68-year-old woman with an 8-year history of parkinsonism which was followed by psychiatric symptoms and neurogenic amyotrophy 5 years after the onset. She had a family history of parkinsonism associated with dementia in all of her three siblings. They grew up in the Hobara village, a focus of amyotrophic lateral sclerosis in the Kii Peninsula of Japan in their childhood. Their parents were not consanguineous nor natives of the Kii Peninsula. The brain weight was 1040 g and there were mild frontal lobe atrophy, moderate atrophy of pes hippocampi, decoloration of the substantia nigra and locus coeruleus, and atrophy of the anterior root of the spinal cord. The microscopic examinations revealed degeneration of CA1 portion of the hippocampus to the parahippocampus gyrus, substantia nigra, locus coeruleus and spinal anterior horn with Bunina bodies. The spinal pyramidal tracts also mildly degenerated. Neurofibrillary tangles (NFT) were observed in the cerebral cortex, especially in the cortices from hippocampus to lateral occipitotemporal gyri, basal nucleus of Mynert, basal ganglia, thalamus, substantia nigra and widespread regions of the central nervous system through the brainstem to spinal cord including the nucleus of Onufrowitcz. In spite of a small amount of the senile plaques in the cerebral cortex and Lewy bodies in the substantia nigra and locus coeruleus, abundant NFT were distributed mainly in the third layer of the cerebral cortex, which is the characteristic feature of ALS/PDC. Thus, this was likely to be an ALS/PDC case outside the Guam Island. A tau mutation was not found on DNA analysis.
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PMID:A clinical and pathological study of a Japanese case of Amyotrophic Lateral Sclerosis/Parkinsonism-Dementia Complex with family history. 1257 46

Since first described, amyotrophic lateral sclerosis/parkinsonism-dementia complex (ALS/PDC) of Guam has represented an important model of age-related neurodegenerative disease. ALS/PDC is characterized neuropathologically by severe widespread involvement by neurofibrillary tangles (NFTs). Over the past 30 years there has been a dramatic decrease in the incidence of ALS and a 10-year increase in the age of onset of ALS and PDC. In 1979, Anderson et al reported evidence of significant NFT involvement in Guam natives who had been free of evidence of neurologic dysfunction. Using the slides from this study, we re-examined the extent of hippocampus and entorhinal NFT involvement and compared it to brains recently obtained from neurologically intact Guam natives and age-matched controls from New York. The tendency towards hippocampal and entorhinal NFT formation continues to be encountered among the inhabitants of Guam, particularly among those over age 50. although severe involvement was less commonly noted in relatively young individuals (< 50 years). As noted by Anderson et al, the pattern of neuropathologic lesions seen in those with extensive NFT involvement suggests that such cases represent preclinical examples of ALS/PDC in individuals who have yet to accumulate a sufficient burden of pathology to attract clinical attention and diagnostic evaluation.
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PMID:Hippocampal and entorhinal cortex neurofibrillary tangle formation in Guamanian Chamorros free of overt neurologic dysfunction. 1272 30

Glutamate transporter proteins appear crucial to controlling levels of glutamate in the central nervous system (CNS). Abnormal and/or decreased levels of various transporters have been observed in amyotrophic lateral sclerosis (ALS) and Alzheimer's disease (AD) and in other neurological disorders. We have assessed glutamate transporter (GLT-1/EAAT2) levels in mice fed washed cycad flour containing a suspected neurotoxin that induces features resembling the Guamanian disorder, ALS-PDC. Down-regulation of glutamate transporter subtypes was detected by immunohistology using antibodies specific for two glial glutamate transporter splice variants (GLT-1alpha and GLT-1B). Immunohistology showed a "patchy" loss of antibody label with the patches centered on blood vessels. Computer densitometry showed significantly decreased GLT-1alpha levels in the spinal cord and primary somatosensory cortex of cycad-fed mice. GLT-1B levels were significantly decreased in the spinal cord, in the motor, somatosensory, and piriform cortices, and in the striatum. Western blots showed a 40% decrease in frontal motor cortex and lumbar spinal cord of cycad-fed mice that appeared to be phosphorylation-dependent. Receptor-binding assays showed decreased NMDA and AMPA receptor levels and increased GABAA receptor levels in cycad-fed mice cortex. These receptor data are consistent with an increased level of extracellular glutamate. The generalized decrease in GLT-1, decreased excitatory amino acid receptor levels, and increased GABAA receptor levels may reflect an early glutamate-mediated excitotoxicity following cycad exposure. Deciphering the series of events leading to neurodegeneration in cycad-fed animals may provide clues leading to therapeutic approaches to halt the early stages of disease progression.
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PMID:Decrease in glial glutamate transporter variants and excitatory amino acid receptor down-regulation in a murine model of ALS-PDC. 1272 93

We present the clinical and genetic characteristics of a Japanese patient with neuropathologically confirmed familial amyotrophic lateral sclerosis/parkinsonism dementia complex (ALS/PDC). The 68-year-old proband with an 8-year history of parkinsonism and neurogenic amyotrophy and her three siblings suffering from parkinsonism associated with dementia originated from the Kii Peninsula of Japan. The proband's brain exhibited mild frontal lobe atrophy, moderate atrophy of the pes hippocampi, decoloration of the substantia nigra and locus coerules, and atrophy of the anterior root of the spinal cord. Microscopic examinations revealed degeneration of the CA1 portion of the hippocampus to the parahippocampus gyrus, substantia nigra, locus coerules and the spinal anterior horn with Bunina bodies. Neurofibrillary tangles (NFTs) were observed in widespread regions of the central nervous system through the cerebral cortex to the spinal cord. The predominant distribution of NFTs in the the third layer of the cerebral cortex was compatible with the characteristic feature of ALS/PDC in Guam. No tau mutation was found in the proband. The lack of mutations in the tau gene not only in this patient but also in earlier reported cases of ALS in the Western Pacific seems to suggest that other genetic factors may be contributing to ALS/PDC.
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PMID:Familial amyotrophic lateral sclerosis and parkinsonism-dementia complex--tauopathy without mutations in the tau gene? 1289 97

Amyotrophic lateral sclerosis/parkinsonism-dementia complex of the Kii peninsula (Kii ALS/PDC) is a neurodegenerative disorder endemic to natives in the southern coast area of the Kii peninsula of Japan. The disorder closely resembles Guamanian ALS/PDC clinically and neuropathologically. The characteristic neuropathological finding is abundant neurofibrillary tangles (NFTs) without amyloid deposition. To elucidate the biochemical properties of hyperphosphorylated tau protein, the major component of the NFTs, we examined Kii ALS/PDC brains by immunoblotting and immunohistochemical analysis using well-characterized anti-tau antibodies specific to phosphorylation-dependent or -independent epitopes. Hyperphosphorylated tau in Kii ALS/PDC had phosphorylated epitopes common to tau of paired helical filaments (PHFs) in Alzheimer disease (AD): immunoblot showed triplet bands composed of 6 tau isoforms. Ultrastructurally, NFTs revealed a twisted filamentous shape similar to PHF of AD. The biochemical properties of its phosphorylated tau protein and the ultrastructural characteristics of the NFTs of Kii ALS/PDC are very similar, if not identical, to PHF tau in AD, although they are different taupopathies.
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PMID:Biochemical and ultrastructural study of neurofibrillary tangles in amyotrophic lateral sclerosis/parkinsonism-dementia complex in the Kii peninsula of Japan. 1290 4

We here report biomagnification (the increasing accumulation of bioactive, often deleterious molecules through higher trophic levels of a food chain) of the neurotoxic nonprotein amino acid beta-methylamino-l-alanine (BMAA) in the Guam ecosystem. Free-living cyanobacteria produce 0.3 microg/g BMAA, but produce 2-37 microg/g as symbionts in the coralloid roots of cycad trees. BMAA is concentrated in the developing reproductive tissues of the cycad Cycas micronesica, averaging 9 microg/g in the fleshy seed sarcotesta and a mean of 1,161 microg/g BMAA in the outermost seed layer. Flying foxes (Pteropus mariannus), which forage on the seeds, accumulate a mean of 3,556 microg/g BMAA. Flying foxes are a prized food item of the indigenous Chamorro people who boil them in coconut cream and eat them whole. Chamorros who die of amyotrophic lateral sclerosis/parkinsonism-dementia complex (AL-SPDC), a neurodegenerative disease with symptoms similar to amyotrophic lateral sclerosis, Parkinson's disease, and Alzheimer's disease, have an average of 6.6 microg/g BMAA in their brain tissues. The biomagnification of BMAA through the Guam ecosystem fits a classic triangle of increasing concentrations of toxic compounds up the food chain. This may explain why the incidence of ALS-PDC among the Chamorro was 50-100 times the incidence of amyotrophic lateral sclerosis elsewhere. Biomagnification of cyanobacterial BMAA may not be unique to Guam; our discovery of BMAA in the brain tissue from Alzheimer's patients from Canada suggests alternative ecological pathways for the bioaccumulation of BMAA in aquatic or terrestrial ecosystems.
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PMID:Biomagnification of cyanobacterial neurotoxins and neurodegenerative disease among the Chamorro people of Guam. 1461 59

Amyotrophic lateral sclerosis/parkinsonism-dementia complex (ALS/PDC) is a progressive neurodegenerative disease affecting the indigenous Chamorro population of Guam. Neuropathologically, PDC is characterized by neuronal loss in the substantia nigra pars compacta with severe widespread neurofibrillary tangles (NFTs) similar to those observed in Alzheimer's disease (AD), and is thus considered a tauopathy. Following reports of alpha-synuclein pathology in PDC patients of Guam, PDC has also been neuropathologically classified as a synucleinopathy. Recently, the presence of alpha-synuclein-positive bodies has been reported in the cerebellum of some patients with Parkinson's disease (PD), diffuse Lewy body disease (DLBD), or multiple system atrophy (MSA). Using immunohistochemical techniques, we investigated the deposition of alpha-synuclein in the cerebellum of Guamanian PDC patients. Numerous alpha-synuclein-immunoreactive spherical structures were found in the molecular layer of the cerebellum of 63.6% of PDC patients. These structures were only seen in patients showing alpha-synuclein pathology in the amygdala. The average density of alpha-synuclein-immunoreactive structures in the cerebellum of Guamanian PDC patients was almost an order of magnitude higher than in non-Guamanian PD patients, and this alpha-synuclein pathology was much more pronounced in the hemisphere than in the vermis. In addition, double immunohistochemistry revealed that cerebellar alpha-synuclein is co-localized with the neuronal marker calbindin and with glial-fibrillary acidic protein, suggesting the involvement of Purkinje cells and Bergmann glia. These findings demonstrate that the alpha-synuclein pathology in PDC of Guam affects not only the amygdala, but also the cerebellum, where it appears to involve both Purkinje cells and specialized astrocytes.
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PMID:Occurrence of alpha-synuclein pathology in the cerebellum of Guamanian patients with parkinsonism-dementia complex. 1502 81

Exposure to cycad (Cycas micronesica K.D. Hill) toxins via diet has been shown to induce neurodegeneration in vivo that mimics the progressive neurological disease, amyotrophic lateral sclerosis--parkinsonism dementia complex (ALS--PDC). In previous studies, specific cortical and subcortical cell loss was measured with conventional stained sections. In the present study, magnetic resonance (MR) microscopy was used to examine neurodegeneration in three dimensions (3D) in isolated intact brains and spinal cords. Mice were fed washed cycad for 2 months and showed progressive motor deficits resembling human ALS--PDC. CNS tissue was imaged at 17.6 T. T2* scans were acquired on both spinal cord and brain samples with an isotropic resolution of 41 microm. Through MR volumetrics, cycad-fed mice showed significantly decreased volumes in lumbar spinal cord gray matter, substantia nigra, striatum, basal nucleus/internal capsule, and olfactory bulb. Cortical measurements of conventionally stained sections revealed that cycad-fed mice also showed decreased cortical thickness. These results show that MR microscopy (MRM) is sensitive enough to measure degeneration in this early stage model of a progressive neurological disease with strong correlations to behavioral deficits and histological results and may be applicable in vivo to the same model. Similar analysis may be used in the future as a diagnostic aid in tracking the early progression of neurological disorders in preclinical human subjects.
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PMID:Quantitative measurement of neurodegeneration in an ALS-PDC model using MR microscopy. 1532 81


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