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)

Phosphorus magnetic resonance spectroscopy (31P-MRS) was used to study in vivo the energy metabolism of brain and skeletal muscle in two members of an Italian pedigree with NARP syndrome due to a point mutation at bp 8993 of mtDNA. In the youngest patient, a 13 year old girl with retinitis pigmentosa, ataxia, and psychomotor retardation, there was an alteration of brain energy metabolism shown by a decreased phosphocreatine content, increased [ADP] and decreased phosphorylation potential. The energy metabolism of her skeletal muscle was also abnormal, as shown by resting higher inorganic phosphate and lower phosphocreatine concentrations than in normal subjects. Her mother, a 41 year old woman with minimal clinical involvement, showed a milder derangement of brain energy metabolism and normal skeletal muscle. Findings with MRS showed that this point mutation of mtDNA is responsible for a derangement of energy metabolism in skeletal muscle and even more so in the brain.
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PMID:Brain and muscle energy metabolism studied in vivo by 31P-magnetic resonance spectroscopy in NARP syndrome. 779 79

Using proton magnetic resonance spectroscopy (1H-MRS) and single photon emission CT (SPECT), the cerebellum of patients with olivopontocerebellar atrophy (OPCA) and of age-matched control subjects was studied. A spectrum was collected from a 27 cm3 (3 x 3 x 3 cm) voxel in the cerebellum containing white and gray matters in order to measure the distribution and relative signal intensities of N-acetylaspartate (NAA), creatine (Cre) and choline (Cho). In the cerebellum of the patients with OPCA, mean NAA/Cre ratios for OPCA patients were significantly decreased compared with normal control subjects (OPCA, 1.01 +/- 0.247; controls, 1.526 +/- 0.144: p < 0.001). Mean NAA/Cho ratios for OPCA patients were slightly decreased (OPCA, 1.285 +/- 0.228; controls 1.702 +/- 0.469: p < 0.06). Cho/Cre ratios valued in the cerebellum of OPCA patients were not significantly different from those in normal controls (OPCA, 0.793 +/- 0.186; controls, 0.946 +/- 0.219). The ratio of RI count in the cerebellum to that in the occipital lobe was significantly decreased in OPCA patients (OPCA, 0.947 +/ 0.096; controls, 1.06 +/- 0.063: p < 0.01). Cerebellar signs were assessed including gait ataxia, limb ataxia, dysarthria, saccadic pursuit, and nystagmus separately or in combination. In patients with more severe ataxic gait and dysarthria. MRS revealed slightly lowered NAA/Cre ratio. There was no significant correlation between NAA/Cre ratio and severity of other clinical signs. The MRS and SPECT findings give a confirmative evidence of hypofunction in cerebellum of patients with OPCA.
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PMID:[Proton magnetic resonance spectroscopy and single photon emission CT in patients with olivopontocerebellar atrophy]. 974 73

A 55-year-old woman, who had two episodes of difficulty in putting a key into a keyhole probably due to optic ataxia at age 52 and 54 years old, developed speaking errors and was admitted to our hospital. She was 152.5 cm in height and 52.5 kg in weight. Neurological examination revealed right homonymous hemianopsia and sensory aphasia. A CSF examination revealed lymphocytic pleocytosis of 88/microliter. Serum lactate and pyruvate were remarkably increased after an aerobic exercise test. A few ragged-red fibers were present in the biopsied brachial biceps muscle. Brain MRI by FLAIR method showed scattered high signal lesions in the left temporal lobe, bilateral parieto-occipital lobes, left insular cortex and left thalamus. The left superficial temporal lesion was enhanced by gadolinium-DTPA. The proton MRS demonstrated the lactic acid peak as well as the decrease of NAA/choline ratio (0.38) in the left parieto-occipital region. Thus, she was diagnosed as a case of MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes) and successfully treated with ubidecarenone (150 mg/day). Six months later, she again developed seizure, right hemiparesis and deterioration of aphasia and presented again CSF lymphocytic pleocytoses of 15/microliter. Brain MRI demonstrated new lesions in the left temporoparietal lobes, left insular cortex and left corona radiata. Therefore, CSF pleocytosis appeared to be associated with stroke-like episodes in this case. Although the mechanism of CSF pleocytosis remains to be elucidated, it may involve the breakdown of blood-brain barrier caused by mitochondrial dysfunction. Otherwise, an inflammatory process similar to that in cases of Leber disease, who developed multiple sclerosis-like additional lesions in the central nervous system, may also take place in MELAS.
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PMID:[A case of MELAS showing CSF pleocytosis associated with stroke-like episodes]. 986 8

Friedreich's ataxia (FA) is the most common form of autosomal recessive spinocerebellar ataxia and is often associated with a cardiomyopathy. The disease is caused by an expanded intronic GAA repeat, which results in deficiency of a mitochondrial protein called frataxin. In the yeast YFH1 knockout model of the disease there is evidence that frataxin deficiency leads to a severe defect of mitochondrial respiration, intramitochondrial iron accumulation, and associated production of oxygen free radicals. Recently, the analysis of FA cardiac and skeletal muscle samples and in vivo phosphorus magnetic resonance spectroscopy (31P-MRS) has confirmed the deficits of respiratory chain complexes in these tissues. The role of oxidative stress in FA is further supported by the accumulation of iron and decreased aconitase activities in cardiac muscle. We used 31P-MRS to evaluate the effect of 6 months of antioxidant treatment (Coenzyme Q10 400 mg/day, vitamin E 2,100 IU/day) on cardiac and calf muscle energy metabolism in 10 FA patients. After only 3 months of treatment, the cardiac phosphocreatine to ATP ratio showed a mean relative increase to 178% (p = 0.03) and the maximum rate of skeletal muscle mitochondrial ATP production increased to 139% (p = 0.01) of their respective baseline values in the FA patients. These improvements, greater in prehypertrophic hearts and in the muscle of patients with longer GAA repeats, were sustained after 6 months of therapy. The neurological and echocardiographic evaluations did not show any consistent benefits of the therapy after 6 months. This study demonstrates partial reversal of a surrogate biochemical marker in FA with antioxidant therapy and supports the evaluation of such therapy as a disease-modifying strategy in this neurodegenerative disorder.
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PMID:Antioxidant treatment improves in vivo cardiac and skeletal muscle bioenergetics in patients with Friedreich's ataxia. 1135 49

We report a 49-year-old previously healthy woman with acute onset of decrease in attention, dysarthria and ataxia, accompanied by drowsiness. On admission, there were cloudness of consciousness, hallucination and left hemiparesis. Cerebrospinal fluid study revealed a cell count of 1/mm3, and the cytology was class I with a slight increase in protein. MRI of the brain performed on admission showed multiple gadolinium-enhanced lesions with a T2 weighted high intensity area in the cerebral white matter. At first the patient was diagnosed as acute disseminated encephalomyelitis (ADEM), and treated with methylprednisolon pulse therapy. Soon after, she showed transient clinical improvement, but her condition soon worsened. MR spectroscopy revealed elevated choline peak, decreased NAA peak and lactate peak, which indicated a neoplastic lesion. The brain biopsy disclosed diffuse intravascular lymphoma (IVL). MRS was useful in the differential diagnosis of IVL from ADEM.
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PMID:[MR spectroscopy findings of a case of intravascular malignant lymphoma: usefulness for differential diagnosis]. 1288 28

We report a 23-year-old man with mitochondrial encephalomyopathy. At 21 years of age, he noted speech distubance. Since his dysarthria did not improve thereafter, he was admitted to our hospital. On admission, he showed mild gynecomastia. Neurological examination revealed mild decrease in performance IQ in WAIS-R, mild scanning speech, mild left hearing disturbance, mild to moderate muscle weakness in proximal four extremities, mild bilateral limb ataxia, and mild to moderate truncal ataxia. While, no brisk deep tendon reflex, pathological reflex, aberrant muscle tonus, sensory disturbance, retinopathy, myoclonus or autonomic disorder was found. Serum levels of lactate (23.2 mg/dl, normal<18.7) and pyruvate (1.23 mg/dl, normal<0.94) were elevated, and serum lactate levels were markedly elevated (118.1 mg/dl) after 15-minute exercise (15 Watts/minute). CSF levels of lactate (31.2 mg/dl, normal<12.5) and pyruvate (1.48 mg/dl, normal<0.75) were also elevated. Head MRI showed mild cerebral and cerebellar atrophy, but 1H-MRS showed no lactate peak. Moreover, muscle biopsy from left biceps muscle showed lots of ragged-red fibers, and he was thus diagnosed as having mitochondrial encephalomyopathy. However, nt3243 mutation of mitochondria DNA was not present. Next, we confirmed gynecomastia by mammography, and checked serum levels of estrogens. Mildly decreased estradiol (19.9 pg/ml, normal, 20-59), normal estrone (24.0 pg/ml, normal<30.0) and mildly increased estriol (6.03 pg/ml, normal<5.0) were found. While, the serum levels of cortisol, dehydroepiandrosterone-sulfate (DHEA-S), androstenedione, testosterone, luteinizing hormone (LH) and follicle stimulating hormone (FSH) were all within normal limits. Since the steroid hormone synthesis system and hypothalamus-pituitary system seem to be normal, 16alpha-hydroxylase that converts estradiol to estriol may be upregulated. While, aromatase (P-450arom) is well known to convert androgens to estrogens. In addition, 16alpha-hydroxylase and P-450arom convert DHEA-S to estriol. Since it is recently reported that P-450arom is considerably expressed in muscle tissues as well as fat tissues and that muscle tissue may be a major organ to produce estrogens in men and postmenopausal women, estriol production may be increased in the present patient's muscle. Although hypogonadism due to hypothalamus-pituitary disorders was sometimes reported, there have been no reports that suggest an increased estrogen production in skeletal muscles in mitochondrial encephalomyopathies. Recently, estrogen has been known to protect muscle fibers from oxidative damages due to exercise. Thus, it is of potential that estrogens increased locally in muscle tissues of the patients with mitochondrial encephalomyopathies protect muscle fibers from oxidative damage due to mitochondrial dysfunction.
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PMID:[A patient with mitochondrial encephalomyopathy presenting gynecomastia with elevation of serum estriol level]. 1528 12

The authors describe four unrelated girls with a distinctive neurologic disorder with early-onset progressive ataxia and hypodontia with a characteristic pattern of delayed dentition. Cerebral MRI shows hypomyelinated white matter and cerebellar atrophy; 1H-MRS of white matter reveals a marked elevation of myo-inositol.
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PMID:Leukoencephalopathy with ataxia, hypodontia, and hypomyelination. 1585 47

We reported a Japanese case of spinocerebellar ataxia type 6 (SCA6) with episodic ataxia type 2 (EA2) phenotype. A 28-year-old woman was admitted to our hospital because of episodic unsteadiness of gait and dysarthria for 4 years. Neurological examination revealed truncal ataxia and dysarthria during attacks, but no abnormal findings in interictal phases. A brain MRI showed no obvious cerebellar atrophy, whereas proton MR spectroscopy (1H-MRS) disclosed decrease of the N-acetylaspartate/ceatine (NAA/Cr) ratio in the cerebellar hemisphere. We identified the expanded 22 CAG repeats without a missense mutation in the CACNA1A gene. After one year from the discharge, her gait ataxia became gradually obvious even in the interictal phase. To our knowledge, although a few foreign papers had reported the SCA6 cases with EA2 phenotype, there is no particular report on such cases in Japan. 1H-MRS, in addition to CAG repeats analysis, might enable us to differentiate SCA6 from EA2, because the latter showed no decrease of NAA/Cr ratio in cerebellar hemisphere according to the previous reports.
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PMID:[A case of spinocerebellar ataxia type 6 with its initial symptom of episodic ataxia-like phenotype]. 1648 24

Friedreich's ataxia (FA) is the most frequent autosomal recessive ataxia and essentially considered a disease of the dorsal root ganglia and spinal cord. It is caused by homozygous GAA expansions in the Frataxin gene in most cases. Although only a few studies have addressed cerebral involvement in FA, cognitive symptoms have lately been emphasized. To evaluate brain damage in vivo, we employed whole-brain VBM and analysis of pre-defined regions of interest (ROIs) over the cerebellum to compare 24 patients with 24 age-and-sex-matched normal controls. (1)H-MRS of deep cerebral white matter (WM) was subsequently performed. Mean age of patients was 28 years (range 14-45), mean duration of disease was 14 years (range 5-28) and 11 were men. Mean length of shorter (GAA1) and longer (GAA2) alleles were 735 and 863, respectively. VBM analysis identified WM atrophy in the posterior cyngulate gyrus, paracentral lobule and middle frontal gyrus. ROIs over the infero-medial cerebellar hemispheres and dorsal brainstem presented gray matter atrophy, which correlated with duration of disease (r = -0.4). NAA/Cr ratios were smaller among patients (P = 0.006), but not Cho/Cr (P = 0.08). Our results provide evidence of axonal damage in the cerebellum, brainstem and subcortical WM in FA. This suggests that neuronal dysfunction is more widespread than previously thought in FA.
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PMID:A combined voxel-based morphometry and 1H-MRS study in patients with Friedreich's ataxia. 1928 Jan 6

Robust biomarkers of neurodegeneration are critical for testing of neuroprotective therapies. The clinical applicability of such biomarkers requires sufficient sensitivity to detect disease in individuals. Here we tested the sensitivity of high field (4 tesla) proton magnetic resonance spectroscopy ((1)H MRS) to neurochemical alterations in the cerebellum and brainstem in spinocerebellar ataxia type 1 (SCA1). We measured neurochemical profiles that consisted of 10 to 15 metabolite concentrations in the vermis, cerebellar hemispheres and pons of patients with SCA1 (N = 9) and healthy controls (N = 15). Total NAA (N-acetylaspartate + N-acetylaspartylglutamate, tNAA) and glutamate were lower and glutamine, myo-inositol and total creatine (creatine + phosphocreatine, tCr) were higher in patients relative to controls, consistent with neuronal dysfunction/loss, gliotic activity, and alterations in glutamate-glutamine cycling and energy metabolism. Changes in tNAA, tCr, myo-inositol, and glutamate levels were discernible in individual spectra and the tNAA/myo-inositol ratio in the cerebellar hemispheres and pons differentiated the patients from controls with 100% specificity and sensitivity. In addition, tNAA, myo-inositol, and glutamate levels in the cerebellar hemispheres and the tNAA and myo-inositol levels in the pons correlated with ataxia scores (Scale for the Assessment and Rating of Ataxia, SARA). Two other biomarkers measured in the cerebrospinal fluid (CSF) of a subset of the volunteers (F(2)-isoprostanes asa marker of oxidative stress and glial fibrillary acidic protein (GFAP) as a marker of gliosis) were not different between patients and controls. These data demonstrate that (1)H MRS biomarkers can be utilized to noninvasively assess neuronal and glial status in individual ataxia patients.
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PMID:Neurochemical alterations in spinocerebellar ataxia type 1 and their correlations with clinical status. 2031 29


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