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)

During the past quarter century biomedical scientists have begun to recognize the unique opportunities for studying disease etiology and mechanisms of pathogenesis in non-Western anthropological populations with focal, endemic diseases. Such natural experiments as they are called, are important paradigms for solving etiological and epidemiological problems of widespread medical significance, with an ultimate goal towards treatment and prevention. The systematic search for etiological factors and mechanisms of pathogenesis of neurodegenerative disorders is perhaps nowhere better exemplified than in the western Pacific. During the past three decades, the opportunistic and multidisciplinary study of hyperendemic foci of amyotrophic lateral sclerosis and parkinsonism-dementia which occur in different cultures, in different ecological zones and among genetically divergent populations have served as natural models that have had a major impact on our thinking and enhanced our understanding of these and other neurodegenerative disorders such as Alzheimer disease and the process of early neuronal aging. Our cross-disciplinary approach to these intriguing neurobiological problems and the accumulated epidemiological, genetic, cellular and molecular evidence strongly implicates environmental factors in their causation, specifically the role of aluminum and its interaction with calcium in neuronal degeneration. As a direct consequence of our studies in these Pacific populations, we have undertaken the long-term development of experimental models of neuronal degeneration, in an attempt to understand the cellular and molecular mechanisms by which these toxicants affect the central nervous system. Our experimental studies have resulted in the establishment of an aluminum-induced chronic myelopathy in rabbits and the development of neurofilamentous lesions after low-dose aluminum administration in cell culture. These studies clearly demonstrate the philosophy that chronic rather than acute experimental models of toxicity are necessary in order to enhance our understanding of human neurodegenerative disorders with long-latency and slow progression. Finally, the ultimate significance of these Pacific paradigms may well depend on our ability to comprehensively evaluate and synthesize the growing body of relevant scientific data from other human disorders and from widely divergent academic fields, as well as our ability to recognize emerging new models in nature.
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PMID:Pacific paradigms of environmentally-induced neurological disorders: clinical, epidemiological and molecular perspectives. 174 28

The epidemiology of amyotrophic lateral sclerosis (ALS) in the Western Pacific indicates that low concentrations of calcium (Ca) and magnesium (Mg) and high levels of aluminum (Al) in soil and water in these foci are etiologically important. To determine the biochemical derangements and metal deposition induced by chronic dietary deficiencies of Ca, we maintained experimental animals on several regimens. Male Wistar rats, weighing 100g, were fed either a standard diet, low Ca diet, low Ca-Mg diet, or low Ca-Mg diet with high Al for 90 days. Ca, Mg and Al content was determined in central nervous system (CNS) tissues and bone using inductively coupled plasma emission spectrometry (ICP). In separate studies, five male Japanese macaques (Macaca fuscata), weighing 3.5 to 5 kg, were fed alternately with diets, normal in Ca, low in Ca, low in Mg, low in Ca-Mg, or low in Ca-Mg with added Al for four-week periods. Serum Ca, Mg, Al, parathyroid hormone (PTH), bone Gla-protein (BGP) and alkaline phosphatase (ALP) were measured after feeding each dietary regimen. Ca and Mg levels in lumbar vertebrae and femur were significantly reduced and bone Al levels were significantly increased in rats fed diets deficient in Ca alone or diets low in Ca-Mg with or without added Al. Al content in bones was also higher in rats fed the Ca deficient diets. In monkeys fed the low Ca-Mg diet with added Al, reduced levels of serum Ca and Mg, serum PTH, BGP, and ALP were apparent. Our data support the conjecture that deranged bone mineralization induced by chronic dietary deficiency of Ca accelerates mobilization of Ca and Mg from bone and deposition in brain.
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PMID:Evaluation of magnesium, calcium and aluminum metabolism in rats and monkeys maintained on calcium-deficient diets. 174 43

Chronic dietary deficiency of calcium (Ca) and magnesium (Mg) with excessive intake of aluminum (Al) and manganese (Mn) has been implicated in the pathogenesis of high incidence amyotrophic lateral sclerosis (ALS) in the Western Pacific. We report two cases of ALS from the Kii Peninsula of Japan with markedly elevated concentrations of Al in central nervous system (CNS) tissues. Six pathologically verified cases of ALS and five neurologically normal controls were studied. Levels of Al, Ca and phosphorus (P) were determined simultaneously by neutron activation analysis (NAA), and Mg concentration was measured by inductively coupled plasma emission spectrometry (ICP) in 26 CNS regions. Al concentrations in the precentral gyrus, internal capsule, crus cerebri and spinal cord were significantly increased in two ALS patients, compared with those of controls. Mean Al concentrations of the 26 CNS regions in these two patients were also higher than those of controls and of the four other ALS cases (p less than 0.01). By contrast, Mg concentrations in the 26 CNS regions were markedly reduced in the ALS cases, compared with controls (p less than 0.01), and the Ca/Mg ratios were significantly increased in the ALS cases (p less than 0.01). Our data indicate that high-incidence ALS in the Western Pacific may result from Ca-Mg dysmetabolism with resultant deposition of Al.
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PMID:Aluminum deposition in the central nervous system of patients with amyotrophic lateral sclerosis from the Kii Peninsula of Japan. 174 44

Current changing epidemiological pattern in the Western Pacific area suggests a contribution of the environmental factors to the pathogenetic process of amyotrophic lateral sclerosis (ALS). The condition of unbalanced mineral levels found in the soil and drinking water samples from the ALS foci showing low content of calcium (Ca) and magnesium (Mg) plus high content of aluminum (Al) was experimentally mimicked in this study using rats. In the groups fed low Ca, low Ca-Mg, and low Ca-Mg plus high Al diets, serum Ca levels were lower than that in the group fed the standard diet. Ca content of CNS tissues showed higher values in the unbalanced diet groups, especially in the spinal cord of low Ca-Mg plus high Al diet group, than those in the standard diet group, determined by inductively-coupled plasma emission spectrometry (ICP). Ca content in heart, liver, kidney, and abdominal aorta in groups fed low Ca-Mg, and low Ca-Mg plus high Al diets was higher than that in low Ca, and standard group. Ca content in muscle in the three unbalanced diet groups was significantly higher than in the standard diet group. Ca and Mg contents in lumbar spine and cortical bone showed lower values in the unbalanced diet groups than those values in the standard diet group. These findings suggest that under the condition of derangement of bone mineralization induced by unbalanced mineral diets fed to the experimental rats, Ca and Mg may be mobilized from bone, keeping their content in soft tissues, including CNS tissue, for utilization of vital activities, thereby resulting in a deposition of Ca while maintaining an almost normal value of magnesium in the CNS tissues.
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PMID:Distribution of calcium in central nervous system tissues and bones of rats maintained on calcium-deficient diets. 175 97

Recent decline in incidence rates of ALS in Guam and the Kii Peninsula of Japan strongly implicates environmental factors rather than inheritance in its causation. Environmental studies in Western Pacific foci showed identical mineral compositions in the soils and drinking water, i.e., extremely low calcium (Ca) and magnesium (Mg) and high aluminum (Al) and manganese (Mn). Series of trace-elemental analyses of the CNS tissue of ALS patients have revealed a high contents of Al and Ca with significant positive correlations between Al and Ca and/or between Ca and Mn, suggesting the prolonged exposure to these trace environment to cause abnormal mineral metabolism detrimental to neurons. Using electron energy loss spectrometry (EELS), Al was found to accumulate within DNA-containing chromatins and rRNA-containing cellular components, i.e., nucleolus, heterochromatin, rough endoplasmic reticulum, in lumbar motor neurons of ALS. Thus, Al may preferentially bind to nucleic acids and cause a progressive inhibition of the protein synthesis of rRNA and the transcription or gene modulation of DNA, leading to neuronal degeneration.
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PMID:[Environmental factors in western Pacific foci of ALS and a possible pathogenetic role of aluminum (Al) in motor neuron degeneration]. 181 96

Elevated levels of aluminum in brain tissue have been found in demented patients with Alzheimer's disease, with ALS-PD complex of Guam and with dialysis encephalopathy. A possible etiological relationship between enhanced aluminum exposure and impaired mental function was suggested both for ALS-PD of Guam (a region where high contents of aluminum in water are found) and for dialysis encephalopathy which appears in dialyzed patients exposed to high doses of aluminum in medications and in dialysate fluid. The role of aluminum in Alzheimer's disease is not known as is the question of life-long aluminum accumulation in healthy human beings. In this review we have limited ourselves to the issue of oral aluminum ingestion and the possible neurotoxic consequences of such exposure. The following topics are summarized: 1. Physiological mechanisms involved in ingestion and intestinal absorption of aluminum and the influences of pH and available organic complexing agents on these processes. 2. Effects of an aluminum-enriched diet on behavior and on brain metabolism. 3. Dietary sources of aluminum and elevated loads of this substance due to prolonged intake of aluminum-containing medications. The main conclusion of this summary is that aluminum is absorbed and may accumulate in different organs in both adults and infants. Two groups seem to be at particular risk for aluminum related toxicity: people with chronic renal failure treated with aluminum-containing medications and pre-term infants fed on aluminum containing formulate. It seems probable that at least upon short term exposure the healthy human body can defend itself adequately from aluminum's toxic effects. However, not enough information is available on possible effects of life-long exposure to aluminum in the environment, diet and medications, which over decades may lead to accumulation of this substance with expressions of toxicity. Therefore, the question of aluminum's relevance to dementive diseases cannot yet be adequately answered.
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PMID:Aluminum ingestion--is it related to dementia? 184 54

Current changing epidemiological pattern in the Western Pacific strongly suggests a contribution of the environmental factors to the pathogenetic process of amyotrophic lateral sclerosis (ALS). As a reflection of excess metals and a deficiency of minerals in soil and water samples in these foci, this study was designed experimentally to evaluate the concentration of calcium (Ca), magnesium (Mg) and aluminum (Al) in the bones of rats fed unbalanced mineral diets. Twenty-eight male Wistar rats, weighing 200 g, were fed either a standard diet, a low Ca diet, a low Ca-Mg diet, or a low Ca-Mg diet with high Al for 90 days. The composition of the diet/100 g consists of Ca 1250 mg, Mg 300 mg, Al 10 mg, Zn 4 mg in the standard diet; Ca 3 mg and Mg 2 mg in the low Ca-Mg diet; and Al 194 mg in the high Al diet, Al supplied as Al lactate. Ca, Mg and Al concentrations were determined by using inductively coupled plasma emission spectrometry (ICP) for bone and atomic absorption spectrometry for serum. Serum Ca levels in the groups fed unbalanced mineral diets were lower than those in the group fed standard diet. Serum Mg levels were markedly decreased in the groups fed low Ca-Mg diet and low Ca-Mg plus high Al diet, compared with those in the groups fed standard diet and low Ca diet.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Evaluation of magnesium, calcium and aluminum deposition in bone in situ]. 191 Sep 40

The monthly intracisternal inoculation of young adult New Zealand white rabbits with low-dose (100 micrograms) aluminum chloride induces aggregates of phosphorylated neurofilament that mimics the intraneuronal inclusions of amyotrophic lateral sclerosis. The chronic progressive myelopathy and topographically-specific motor neuron degeneration that occurs in the absence of suppressions of neurofilament messenger RNA levels in this model contrasts with the acute fulminant encephalomyelopathy and nonspecific gene suppressions that occur subsequent to high-dose (1000 micrograms) aluminum chloride inoculations. Further analysis of this unique model of chronic motor system degeneration can be expected to provide additional insights into the pathogenesis of amyotrophic lateral sclerosis.
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PMID:Chronic aluminum-induced motor neuron degeneration: clinical, neuropathological and molecular biological aspects. 193 93

We report two cases of amyotrophic lateral sclerosis (ALS), in which metal analysis revealed markedly higher aluminum concentration in the central nervous system (CNS) as well as higher calcium and lower magnesium concentration and higher Ca/Mg ratios compared with controls. Case 1 was a 55-year-old housewife and total duration of illness was 2 years and 2 mon from onset of clinical symptom. Case 2 was a 80-year-old woman and total duration of illness was 10 mon. Results showed that neither were exposed to toxic environments nor any neurologic disease in the past history. Postmortem examination disclosed motor neuron death and degeneration of pyramidal tracts. The significance of metal metabolism in pathogenesis of amyotrophic lateral sclerosis is discussed.
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PMID:High aluminum deposition in the central nervous system of patients with amyotrophic lateral sclerosis from the Kii Peninsula, Japan: two case reports. 195 86

Recent epidemiological changes in patterns of foci of amyotrophic lateral sclerosis (ALS) in the Western Pacific suggest that environmental factors play a contributory role in the pathogenic process of this disorder. In this experimental study on rats, a similar situation of dietary mineral imbalance was created as is found in the soil and drinking water of these ALS foci with a low content of calcium (Ca) and magnesium (Mg) and a high content of aluminum (Al). In groups of rats fed a low Ca diet, low Ca-Mg diet, and low Ca-Mg plus high Al diet, serum Ca levels were found to be lower than those in a group fed a standard diet. Also, serum Mg levels were lower in the groups fed a low Ca-Mg diet and a low Ca-Mg plus high Al diet than in the groups fed a standard diet and only a low Ca diet. There was no significant difference in Mg content of central nervous system (CNS) tissues of groups fed unbalanced and standard diets, except for a significant decrease in Mg content of the spinal cord of rats fed a low Ca-Mg plus high Al diet. Mg content of the lumbar spine and cortical bone decreased in the unbalanced diet groups compared with that of a group fed a standard diet. These findings suggest that under the disturbed bone mineralization induced by unbalanced mineral diets, Mg may be mobilized from bone to maintain the level necessary for vital activity in soft tissues including CNS tissue.
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PMID:Distribution of magnesium in central nervous system tissue, trabecular and cortical bone in rats fed with unbalanced diets of minerals. 208 24


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