Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.20 (alpha-glucosidase)
4,237 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A diagnosis of infantile Pompe's disease (glycogenosis type II) was made by muscle biopsy on a 6-month-old infant boy seen with hypotonia, weakness, and developmental regression. Histochemistry and electron microscopy revealed a vacuolar myopathy with massive glycoge accumulation associated with increased neutral lipid as demonstrated on Oil Red O reactions. Pleomorphic, hypertrophic mitochondria with distortion of cristae and electron-dense deposits within the matrix were identified. Acid alpha-1,4-glucosidase activity was absent but associated with increased neutral maltase activity and a variable compensatory rise in activity of other lysosomal enzymes. Biochemical studies demonstrated low free carnitine, normal acylcarnitine, increased activity of carnitine palmityl and acyl transferases, and other enzymes of beta-oxidation with the notable exception of low normal beta-hydroxyacyl-CoA dehydrogenase activity. The explanation for the lipid accumulation is uncertain but is likely related to the combination of low carnitine concentration in muscle, low beta-hydroxyacyl CoA dehydrogenase, representing a rate limiting enzyme of beta-oxidation, and nonspecific defective mitochondrial function.
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PMID:Infantile Pompe's disease, lipid storage, and partial carnitine deficiency. 187 Jun 35

Acid maltase deficiency in adults is associated with progressive muscle weakness and may effect respiratory muscles resulting in respiratory failure. The biochemical and clinical manifestations of acid maltase deficiency arise from a marked deficiency of the lysosomal enzyme alpha-glucosidase (acid maltase), which normally degrades glycogen to free glucose. In the past few years, high-protein diets have provided an alternative energy source for these patients and resulted in improved muscle strength. Recently, we treated a ventilator-dependent acid maltase-deficient patient with a general diet supplemented with branched-chain amino acids. Branched-chain amino acids are the principal amino acids involved in muscle protein synthesis and utilization. While on this diet, the patient had improvement of respiratory function and muscle strength and was able to be weaned from the ventilator during the day. In addition to his nutritional status, levels of serum branched-chain amino acids, showed improvement within 2 months after the diet started. This diet shows potential advantages over a high-protein diet without supplemented branched-chain amino acids for the treatment of acid maltase deficiency. These include theoretical sparing of amino acids required for muscle protein synthesis by providing higher concentrations of postprandial branched-chain amino acids in the circulation. Also, the liquid formula would be better tolerated by a ventilator-dependent or debilitated patient rather than a high-protein general diet. Further experience with branched-chain amino acid formulas will be needed to substantiate their efficacy in the treatment of acid maltase deficiency.
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PMID:Treatment of acid maltase deficiency with a diet high in branched-chain amino acids. 211 30

A case of 25-year-old woman with glycogen storage myopathy is reported here. She was hospitalized for acute heart failure after alcohol drinking. The electrocardiogram on admission showed marked ST elevation. Laboratory data showed elevated levels of serum myogenic enzymes but no rise in cardiomyogenic enzyme: CK 3862 IU/l CK-MB 35 IU/l, LDH 427 IU/l, GOT 203 IU/l. After several days, she recovered from acute heart failure and could walk without supporting. ST elevation in ECG and elevated myogenic enzymes were also normalized. The occurrence of acute myocardial infarction was ruled out because a coronary angiogram and 99 Tcm scintigram were normal. Physical examination revealed proximal muscular weakness and mental retardation (WAIS, total 72). Venous lactate response was normal after semi-ischemic forearm exercise. PAS staining of muscle specimen showed an excess deposit of glycogen. Ragged-red fibers were not seen on Gomori-trichrome stain. By electron microscopy, a large amount of glycogen particles were demonstrated in the subsarcolemma, but there were no abnormal mitochondrial changes. Biochemical analysis showed accumulation of glycogen in muscles: 28.7 mg/g muscle (normal 11.4 +/- 4.2 mg/g muscle). The activities of enzyme in the pathway of glycogen and glycogenosis (alpha-glucosidase, amylo-1,6-glucosidase, phosphorylase a, phosphorylase kinase, phosphofructokinase, etc.) were within normal limits. The spectrum of glycogen iodine complex was normal. Our case was different from any type of muscle glycogen storage disease previously reported. The etiology of an excess of glycogen deposit in muscles is unknown.
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PMID:[A case of glycogen storage myopathy with acute heart failure]. 220 34

We report a study of an adult with a maltase acid deficiency myopathy. A restrictive respiratory syndrome due to respiratory muscle weakness is associated with paralysis of other muscular groups. In 1982 the patient presented with an alveolar hypoventilation, and mechanical ventilation was required after acute respiratory failure. The patient has received nocturnal mechanical ventilation by tracheostomy at home for 5 years. His clinical status gradually improved in parallel to amelioration of his respiratory condition. Functional respiratory tests improved: initial hypoxia-hypercapnia disappeared, vital capacity increased. The possible mechanisms underlying the improvement are discussed. Increase in pulmonary compliance is an argument to explain the functional improvement observed. Ventilatory response to carbon dioxide was abnormal whereas the ventilatory response to exercise and maxima minute ventilation test were normal. Results are consistent with a respiratory control impairment. The role of mechanical ventilation is difficult to assess in the improvement we observed.
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PMID:Adult maltase acid deficiency myopathy: treatment with long-term home mechanical ventilation. 305 36

Glycogen deposition in vascular smooth muscle has been demonstrated previously in alpha-glucosidase deficiency but has not been clinically significant. Three sons of healthy, nonconsanguineous parents developed progressive proximal muscular weakness secondary to alpha-glucosidase deficiency. Each patient developed a fusiform basilar artery aneurysm, which was complicated by fatal rupture in two patients and a cerebellar infarction in the third. Postmortem examination demonstrated severe vacuolation of skeletal muscle, liver, and vascular smooth muscle with accumulation of periodic acid-Schiff-positive, diastase-sensitive material. In the surviving brother, similar glycogen deposition was demonstrated in the smooth muscle of the superficial temporal artery. Basilar artery aneurysm formation in this sibship may be a consequence of alpha-glucosidase deficiency.
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PMID:Alpha-glucosidase deficiency and basilar artery aneurysm: report of a sibship. 332 84

We report on a 2-yr-old boy with progressive muscular weakness and respiratory failure. There was no clinical evidence of heart muscle involvement. Autopsy showed marked intralysosomal glycogen deposition in skeletal muscle and liver with no histological evidence of glycogen deposition in cardiac muscle. The activity of the lysosomal enzyme alpha-1,4-glucosidase was deficient in skin fibroblasts, skeletal muscle, cardiac muscle, and liver; however, the enzymatic activity in peripheral blood leukocytes was in the low normal range. The child's mother had normal enzymatic activity in leukocytes but heterozygote levels in skin fibroblasts.
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PMID:The "muscular variant" of Pompe disease: clinical, biochemical and histologic characteristics. 389 31

A newly recognized inherited metabolic disease in the Lapland dog is described. The metabolic defect is a deficiency of acid-alpha-glucosidase, a lysosomal hydrolase. The clinical picture is dominated by vomiting related to megaoesophagus, and progressive muscle weakness leading to exhaustion and death before two years of age. Cardiac abnormalities are observed. The main histopathologic lesion consists of glycogen accumulation, notably in membrane-bound vacuoles (glycogenosomes), involving all kinds of muscular tissue in particular. Recessive inheritance of the disease was demonstrated by complementation analysis. The enzyme protein is present in affected tissues, although in an inactive form. Based on the gene dosage phenomenon, an attempt was made to identify carrier dogs by means of a biochemical assay. Glycogen storage disease type II in the Lapland dog appears to be a homologous model for the infantile manifestation of glycogen storage disease type II (Pompe's disease) in man.
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PMID:Glycogen storage disease type II in the Lapland dog. 390 97

Three children, including two siblings and a patient with sporadic glycogenosis type II (childhood form of acid maltase deficiency [AMD] ), were studied clinically, biochemically, and morphologically. In addition to a delay in developmental milestones and mild generalized muscle weakness, nasal vocalization and an electromyographic finding of abnormal insertion voltage, followed by pseudomyotonic discharge, were assumed to be characteristic diagnostic findings for the childhood form of AMD. Since the neutral maltase activity was highest in the muscle biopsy specimen from the patient with the least severe weakness, the enzyme may play a role in reducing muscle involvement. Selective type 2A fiber atrophy and type 2B fiber deficiency in the affected muscles were the common histochemical findings in this particular form of AMD.
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PMID:Childhood acid maltase deficiency. A clinical, biochemical, and morphologic study of three patients. 636 Jan 3

An infant died at 8 months of age with a history of developmental regression, hypotonia, severe weakness, cardiomegaly, congestive heart failure, and hepatomegaly. A diagnosis of Pompe's disease (glycogenosis type II) was established by muscle biopsy at 5 months of age. Vacuolar myopathy involved muscle fibers of histochemical type I more than type II. Many vacuoles were filled with glycogen. In addition, increased amounts of neutral lipid were demonstrated by oil red O stain, electron microscopy, and quantitative analysis. Acid alpha-1,4-glucosidase activity was demonstrated to be deficient. Biochemical studies failed to determine the cause of the lipid accumulation, but demonstrated a low total concentration of carnitine in the muscle (6.37 nmole/mg of protein), associated with elevated activities of carnitine palmityl-transferase and palmityl-coenzyme A dehydrogenase. Palmityl-coenzyme A synthetase activity was in the normal range.
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PMID:Lipid storage myopathy in infantile Pompe's disease. 646 16

We performed a clinical, biochemical, and genetic study in 16 patients from 11 families with adult-onset acid maltase deficiency. All patients were compound heterozygotes and carried the IVS1(-13T --> G) transversion on one allele; the second allele harbored either a deletion of a T at position 525 in exon 2 (7 probands, 64%) or a deletion of exon 18 (1 proband, 9%). Deterioration of handicap was related to age, and decrease in vital capacity to duration of the symptomatic stage. Respiratory insufficiency was never the first manifestation. The levels of activity of serum creatine kinase and of alpha-glucosidase in peripheral blood cells or muscle were helpful for the diagnosis, but did not have prognostic value. The adult form of acid maltase deficiency appears to be both clinically and genetically rather homogeneous; decrease of alpha-glucosidase activity is the final common pathway leading to destruction of muscle fibers and progression of muscle weakness over a period of years.
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PMID:Genotype-phenotype correlation in adult-onset acid maltase deficiency. 766 32


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