Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004134 (ataxia)
 15,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Propylene glycol (1,2-propanediol) is a solvent in numerous pharmaceuticals and a major preservative and source of carbohydrates in processed foods. In mammals, propylene glycol is metabolized similar to ethanol, proceeding via hepatic alcohol and aldehyde dehydrogenases to lactate, which can then enter gluconeogenesis. We observed that cats ingesting 1.6 gm of propylene glycol/kg body weight/day developed increased anion gap. To investigate this further, we measured D- and L-lactate concentrations in these cats; we also measured D-lactate in cats ingesting high doses of propylene glycol (8.0 gm/kg). While L-lactate actually decreased throughout the 35-day course of propylene glycol feeding, D-lactate levels were significantly increased on a dose-dependent basis and correlated positively with anion gap. In cats ingesting the high dose of propylene glycol, D-lactate concentrations were as high as 7 mmol/liter, levels associated with encephalopathy in humans. Indeed, this group of cats developed depression and ataxia, consistent with intoxication by D-lactate. These findings are significant not only for animals ingesting diets which contain propylene glycol, but for humans who receive propylene glycol-containing medications.
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PMID:Propylene glycol ingestion causes D-lactic acidosis. 229 57

Acetaldehyde has been reported, but has not been proven, to be the toxic entity resulting from metaldehyde ingestion. To investigate this, male dogs were given a single dose of 600 mg metaldehyde or acetaldehyde/kg of body wt via stomach tube. Clinical signs were monitored, and plasma and urine were assayed for metaldehyde and acetaldehyde. Vomiting occurred less often and in a significantly lower number of metaldehyde-dosed dogs than in acetaldehyde-dosed dogs. Ataxia and tremors occurred significantly more often in metaldehyde-dosed dogs than in acetaldehyde-dosed dogs. Acetaldehyde was not detected in the plasma or urine of metaldehyde-dosed dogs, however, it was found in a sample of vomitus from one of the metaldehyde-dosed dogs. Metaldehyde was found in plasma and urine of metaldehyde-dosed dogs. Urinary excretion of metaldehyde from the metaldehyde-dosed dogs was less than 1%. Urinary excretion of acetaldehyde from acetaldehyde-dosed dogs was essentially nonexistent. Metaldehyde has a larger role in the mechanism of metaldehyde toxicity than previously thought. While acetaldehyde appeared to be of significantly lesser importance, we could not eliminate it as a factor in metaldehyde toxicity in dogs.
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PMID:An investigation of metaldehyde and acetaldehyde toxicities in dogs. 308 27

Eleven alcoholics with cerebellar degeneration (eight with computerized tomography confirmation of cerebellar atrophy) were matched with nonataxic alcoholics and nonalcoholics. There were no laboratory or physiological markers for ataxia, including hemoglobin A1a + b, red blood cell transketolase, liver function enzymes, and measures of reaction time and hand-eye coordination. Acetaldehyde-modified hemoglobin levels (as hemoglobin A1a + b) did not, as previously reported, distinguish between alcoholics and nonalcoholics. There was 24% less annual alcohol consumption in ataxic alcoholics compared with nonataxic alcoholics, 9% less lifetime consumption in ataxic alcoholics, and 33% less maximal daily intake. The finding that ataxic alcoholics do not have higher alcohol consumption than nonataxic alcoholics suggests that alcoholic cerebellar degeneration is not a dose-dependent phenomenon, and that alcoholics with cerebellar degeneration may have an idiosyncratic sensitivity to the neuronal effects of alcohol.
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PMID:Alcoholic cerebellar degeneration is not a dose-dependent phenomenon. 330 8

Although ethanol is typically classed as a sedative-hypnotic, low doses of ethanol have been shown to stimulate locomotor activity in mice. However, in rats the typical response to peripheral administration of ethanol is a dose-dependent suppression of motor activity and operant responding. The present study was undertaken to determine the effects of intraventricular (ICV) infusions of ethanol, acetaldehyde, and acetate on operant performance in rats. ICV injections of ethanol, acetaldehyde, or acetate were given to rats previously trained on either a differential-reinforcement-of-low-rates-of-responding (DRL) 30-s schedule, which generates low rates of responding, or a fixed ratio 5 (FR5) schedule, which generates relatively high rates. Ethanol, acetaldehyde, and acetate all produced a rate-increasing effect in rats on the DRL 30-s schedule at moderate doses (2.8 and 1.4 micromol, respectively). Acetate also produced a rate-decreasing effect on the DRL 30-s schedule at a larger dose (8.8 micromol). Performance on the FR5 schedule was unaltered by ethanol and acetaldehyde, even at doses as high as 17.6 micromol. However, acetate produced a rate-decreasing effect on the FR5 schedule at doses of 4.4, 5.6, and 8.8 micromol. Central administration of low doses of ethanol and its metabolites can increase operant responding on some schedules in rats. Acetate is the substance that is most potent for producing rate-suppressing effects. These results indicate that the major metabolites of ethanol are pharmacologically active when injected into the brain, and suggest that acetate may mediate some of the rate-suppressing effects of ethanol, such as sedation, ataxia or motor slowing.
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PMID:Behavioral effects of intraventricular injections of low doses of ethanol, acetaldehyde, and acetate in rats: studies with low and high rate operant schedules. 1465 86

Aprataxin is the causative gene product for early-onset ataxia with ocular motor apraxia and hypoalbuminemia/ataxia with oculomotor apraxia type 1 (EAOH/AOA1), the clinical symptoms of which are predominantly neurological. Although aprataxin has been suggested to be related to DNA single-strand break repair (SSBR), the physiological function of aprataxin remains to be elucidated. DNA single-strand breaks (SSBs) continually produced by endogenous reactive oxygen species or exogenous genotoxic agents, typically possess damaged 3'-ends including 3'-phosphate, 3'-phosphoglycolate, or 3'-alpha, beta-unsaturated aldehyde ends. These damaged 3'-ends should be restored to 3'-hydroxyl ends for subsequent repair processes. Here we demonstrate by in vitro assay that recombinant human aprataxin specifically removes 3'-phosphoglycolate and 3'-phosphate ends at DNA 3'-ends, but not 3'-alpha, beta-unsaturated aldehyde ends, and can act with DNA polymerase beta and DNA ligase III to repair SSBs with these damaged 3'-ends. Furthermore, disease-associated mutant forms of aprataxin lack this removal activity. The findings indicate that aprataxin has an important role in SSBR, that is, it removes blocking molecules from 3'-ends, and that the accumulation of unrepaired SSBs with damaged 3'-ends underlies the pathogenesis of EAOH/AOA1. The findings will provide new insight into the mechanism underlying degeneration and DNA repair in neurons.
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PMID:Aprataxin, causative gene product for EAOH/AOA1, repairs DNA single-strand breaks with damaged 3'-phosphate and 3'-phosphoglycolate ends. 1751 53

Recent advance of molecular biology reveals that quality control of intracellular environment takes an important role for maintaining the neuronal function. One is a quality control of protein and another is a quality control of nucleotide. Polyglutamine disease is a disease which caused by a failure of quality control of protein. Expanded polyglutamine repeats result in neurodegenerative disorders, but their cytotoxic structures remain to be elucidated. We have applied fluorescence resonance energy transfer analysis to clarify the cytotoxicity of soluble polyglutamine oligomers. By using this method we revealed that polyglutamine monomers assemble into oligomer in a parallel beta-sheet or a head-to-tail cylindrical beta-sheet manner. We distinguished oligomers from monomers and inclusion bodies in a single living cell. Survival assay of neuronally differentiated cells revealed that cells with soluble oligomers died faster than those with inclusion bodies or monomers. These results indicate that a formation of oligomers is an essential mechanism underlying neurodegeneration in polyglutamine-mediated disorders. About the quality control of nucleotide in neuron, DNA single-strand breaks were continually produced by endogenous reactive oxygen species or exogenous genotoxic agents. These damaged ends posses damaged 3'-ends including 3'-phosphate, 3'-phosphoglycolate, or 3'-alpha, beta-unsaturated aldehyde ends, and should be restored to 3'-hydroxyl ends for subsequent repair processes. We have demonstrated by in vitro assay that aprataxin, the causative gene product for early-onset ataxia with ocular motor apraxia and hypoalbuminemia/ataxia with oculomotor apraxia type 1 (EAOH/AOA1), specifically removes 3'-phosphoglycolate and 3'-phosphate ends at DNA 3'-ends, but not 3'-alpha, beta-unsaturated aldehyde ends. The findings indicate that aprataxin removes blocking molecules from 3'-ends, and that the accumulation of unrepaired DNA single-strand breaks with damaged 3'-ends underlies the pathogenesis of EAOH/AOA1. The findings will provide new insight into the mechanism underlying degeneration and DNA repair in neurons. Taken together, these results indicate that the quality control of protein and nucleotide is crucial to understand the neurodegenerative disorder.
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PMID:[Molecular mechanism for spinocerebellar ataxias]. 1922 89

Recent advance of molecular biology reveals that quality control of intracellular environment takes an important role for maintaining the neuronal function. One is a quality control of protein and another is a quality control of nucleotide. Polyglutamine disease is a disease which caused by a failure of quality control of protein. Expanded polyglutamine repeats result in neurodegenerative disorders, but their cytotoxic structures remain to be elucidated. About the quality control of nucleotide in neuron, DNA single-strand breaks (SSBs) were continually produced by endogenous reactive oxygen species or exogenous genotoxic agents. These damaged ends posses damaged 3'-ends including 3'-phosphate, 3'-phosphoglycolate, or 3'-alpha, beta-unsaturated aldehyde ends, and should be restored to 3'-hydroxyl ends for subsequent repair processes. We have demonstrated by in vitro assay that aprataxin, the causative gene product for early-onset ataxia with ocular motor apraxia and hypoalbuminemia/ ataxia with oculomotor apraxia type 1 (EAOH/AOA1), specifically removes 3'-phosphoglycolate and 3'-phosphate ends at DNA 3'-ends, but not 3'-alpha, beta-unsaturated aldehyde ends. The findings indicate that aprataxin removes blocking molecules from 3'-ends, and that the accumulation of unrepaired SSBs with damaged 3'-ends underlies the pathogenesis of EAOH/AOA1. The findings will provide new insight into the mechanism underlying degeneration and DNA repair in neurons.
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PMID:[Molecular mechanism for spinocerebellar ataxias]. 2003 Feb 1