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An unusual patient with Andersen disease (glycogenosis type IV) is presented, with only relatively mild clinical symptoms at the age of 8 years. The patient has a profound deficiency of glycogen-branching enzyme.
One normal and two carrier calves, and two calves affected by generalized glycogenosis type II were given multiple transplants of normal bovine amnion inserted below the external oblique abdominal muscle in the flank. The interval between transplants was approximately 5 months. The amniotic tissue was not acutely rejected but a host versus graft reaction did occur. The level of acid alpha-glucosidase activity in the amniotic tissue fell rapidly but was still present 2 months after transplantation. Enzyme levels in blood or other tissues did not rise. Excess glycogen deposition and muscle damage occurred in the affected calves and appeared to progress at a rate similar to that in untreated affected animals. One of the affected animals died aged 16 months, which was the same age as the longest surviving non-treated animal in our herd. The other treated animal died aged 24 months.
Prenatal diagnosis of type 2 glycogenosis (Pompe's disease) has been done on cultured amniotic fluid cells, using a semi-automated fluorimetric kinetic assay for alpha-D-glucosidase with 4-methylumbelliferyl-alpha-D-glucoside as substrate. The activity of the enzyme was related to that of beta-D-galactosidase, and found to be absent in cells from an affected fetus. The diagnosis was confirmed in fetal liver, where the same assay was used to show absence of alpha-D-glucosidase activity with normal beta-D-galactosidase activity, and where increased glycogen deposition was demonstrated histologically. This type of assay is generally applicable to lysosomal enzymes, and to other fluorigenic enzyme reactions.
This paper reports the first prenatal diagnosis in a pregnancy at risk for type III glycogenosis using a reliable test for amylo-1,6-glucosidase in cultured amniotic fluid cells. This test, based upon the different rates of glycogen and phosphorylase limit dextrin hydrolysis, was found to be more reliable in detecting a deficiency of amylo-1,6-glucosidase activity than either phosphorylase limit dextrin hydrolysis alone or [14C]glucose incorporation using leukocytes and cultured cells.
We report a longitudinal study of 41 patients with liver glycogenosis due to phosphorylase kinase deficiency. In their youth, patients displayed hepatomegaly (92%), growth retardation (68%), delayed motor development (52%), hypercholesterolaemia (76%), hypertriglyceridaemia (70%), elevation of glutamate pyruvate transaminase (56%) and fasting hyperketosis (44%). With age, these clinical and biochemical abnormalities gradually disappeared and most adult patients were asymptomatic.
Glycogenosis type V (McArdle) was the first myopathy to be enzymatically defined myopathy and has been found in approximately 120 patients. It is characterized by a myophosphorylase defect. In 2 patients with completely missing phosphorylase activity, muscle fiber necrosis and creatinine kinase elevation, we found reproducibly low gammaglobulins and low immunoglobulin-G. Compared with 124 nonmyopathic control patients with hypogammaglobulinemia, we did not find any established cause for low gammaglobulins in either case of McArdle disease. Myopathies with selected laboratory features or histopathology in common did not show changes in gammaglobulins or immunoglobulins. Unaffected family members had normal gamma-globulins and immunoglobulins. Therefore, gammaglobulins indicate an immunologic involvement in phosphorylase deficiency, and a potential for genomic co-localization.
We report here cDNA and genomic sequence of the bovine acidic alpha-glucosidase gene, from the initiation codon to the most 3' polyadenylation signal. The 2814-bp coding sequence predicts a 937-amino acid protein, which is highly conserved compared with the human alpha-glucosidase gene (86% and 83% identity respectively). The intron/exon boundaries are also conserved between the two species. Two mutations have been identified in Brahmans, and one in Shorthorns, that lead to generalized glycogenosis. All three mutations result in premature termination of translation. Evidence is also presented for a missense mutation segregating with the Brahman population, which is responsible for a 70-80% reduction in alpha-glucosidase activity.
Eight patients with adult-onset type II glycogenosis (GSD II), all carrying the IVS1-13T<G mutation, were treated with high-protein isocaloric diet for 3 years. We evaluated the usefulness of this approach through the assessment of the skeletal muscles (by manual muscle testing, quantitative isokinetic exercise, and muscle MRI) and the respiratory function (by spirometry). Three patients with mild or moderate disease severity refused the diet and were still monitored for comparison: they showed clinical (2 patients) or clinicoradiological (1 patient) progression of muscle weakness, while respiratory function remained unchanged. Among the patients accepting the dietary treatment, muscle strength remained unchanged, as did the degree of fatty infiltration and atrophy as assessed by muscle MRI; respiratory function worsened in 2/5 patients with severe baseline respiratory dysfunction. High-protein diet may stabilize disease progression at the skeletal muscles, but does not produce significant clinical improvements; moreover, the usefulness of this approach in patients with severe respiratory disease seems questionable.
Ten out of 47 calves that were born in a small Brahman herd from southern Brazil developed progressive muscular weakness and tremors, lethargy and poor body condition. Necropsy was performed on three affected animals. The only gross lesion detected was paleness of the muscles of the trunk and limbs. Multiple cytoplasm vacuoles located in different tissues were the principal microscopic lesions. Vacuoles were particularly evident in skeletal muscles and myocardium. PAS-positive granules were numerous in skeletal muscle fibres and Purkinje fibres of the myocardium, but were also observed in the neurons of the brain and spinal cord, and in the vascular smooth muscle fibres from all the examined tissues. Pretreatment with diastase completely abolished the PAS reactivity. The vacuoles reacted strongly to Griffonia simplicifolia II and Concanavalia ensiformes lectins, whose biding pattern has been reported as useful for demonstration of glycogen. Examination of the electron micrographs revealed that glycogen was free within the cytoplasm or accumulated in membrane-bound granules of several tissues, especially in striated muscle, liver and neurons of the CNS. These findings were consistent with generalized glycogenosis.
The physico-chemical and immunological properties of acid alpha-glucosidase from various human tissues have been studied. Heat stability of acid alpha-glucosidase from heart, liver and skeletal muscle is identical, but for kidney some different results are obtained. Identical isoelectrofocussing patterns are found for heart, liver and skeletal muscle. Furthermore, the effect of antiserum against human liver acid alpha-glucosidase on the activity of acid alpha-glucosidase from various tissues is studied. The results are discussed in relation to glycogenosis type II (Pompe's disease).
The physico-chemical and electrophoretical properties of alpha-glucosidases from various human tissues and urine have been studied. There were some differences among Peak I enzymes (neutral alpha-glucosidases) obtained from liver, heart, muscle, kidney and urine. These differences are based on different effects of tris(hydroxymethyl)aminomethane and various thermostabilities of the Peak I enzymes. Electrophoretically, the Peak I enzyme activity at pH 6.5 from control tissues displayed a two-banded pattern except in kidney and urine. In the patient with the adult form of Pompe's disease the faster band of the Peak I enzyme from heart and muscle was not found and the slower band of the Peak I enzyme from liver was more cathodic. The results are discussed in relation to glycogenosis type II (Pompe's disease).
The authors describe four cases of atypical forms of glycogenosis with alpha-1,4-glucosidase (acid maltase) deficiency. The results of clinical, microscopic, histochemical, enzymological and immunological studies are described. Acid maltase activity has been studied in muscle, leukocytes and fibroblasts. The authors show no difference in the properties of acid maltase; the authors study the purified enzyme from various tissues.
Two patients with apparent clinical manifestations of glycogen storage disease were described. The curves obtained upon glucose and adrenalin tolerance tests were indicative of glycogen storage disease Type I. Liver biopsies showed the increased glycogen concentration; however, the activities of the enzymes involved in glycogen metabolism, including glucose-6-phosphatase activity, were within normal limits or even slightly enhanced. On the basis of the biochemical data, Type Ib glycogenosis was diagnosed. The analytical ultracentrifugation studies of serum lipoproteins of those patients showed that concentration of very low density lipoproteins was considerably increased.
In the kidneys of two infants who died from glycogenosis type II (deficiency of lysosomal acid alpha-glucosidase) the activity of alpha-glucosidase at acid pH was absent only from the medulla but not the cortex. This prompted an investigation of acid and neutral alpha-glucosidases of the two zones of normal human kidney and of liver. In the kidney medulla, a single, fast migrating electrophoretic band was active at neutral but not at acid pH. In the cortex, three additional bands were detected at neutral pH and two in the liver. One slowly migrating band was unique to the cortex and active over a broad pH range. It had comparatively high sensitivity to the inhibitor turanose and high heat stability. Its properties suggested a close relationship or identity to glucoamylase of the intestinal brush border membrane and to alpha-glucosidase in leukocytes and amniotic fluid and cells.
This ultrastructural investigation on renal collecting duct cells and hepatocytes of rats deals with the question of whether or not lipid-storage lysosomes as induced by cationic amphiphilic compounds retain their ability to fuse with autophagosomes/autolysosomes. These were recognized by their glycogen content which was made to persist by means of acarbose, an inhibitor of lysosomal alpha-glucosidase. To induce lipidosis, rats were pretreated for several weeks with chloroquine or chlorphentermine; they then received combined treatment with the lipidosis-inducing drug plus acarbose. In renal collecting duct cells, mixed storage lysosomes displaying the features of both lipidosis and glycogenosis were found to predominate, indicating that fusion between lipid-laden lysosomes and glycogen-containing autophagosomes/autolysosomes was efficient. Hepatocytes also displayed some mixed storage lysosomes; these were, however, regularly accompanied, within a given hepatocyte, by greater numbers of pure lipidosis-related inclusions and pure glycogen vacuoles. This observation indicates that in hepatocytes lipid-storage lysosomes were rather reluctant to fuse, thus displaying a feature of telolysosomes which are no longer capable of participating in cellular digestion.
The activity of acid alpha-glucosidase in cultured fibroblasts from adult patients with the lysosomal storage disease glycogenosis type II is only 10% of normal. A normal activity per molecule is found for the mature as well as for the precursor form of acid alpha-glucosidase in adult mutant fibroblasts. Excessive lysosomal breakdown of mature enzyme purified from mutant fibroblasts and taken up by acceptor cells does not occur. However, the NH4Cl-stimulated secretion of a precursor form of acid alpha-glucosidase by adult mutant fibroblasts is markedly reduced. The results are indicative of a defect during the production of acid alpha-glucosidase.
acid alpha-glucosidase (EC 3.2.1.20) was purified from fetal bovine muscle by affinity chromatography on concanavalin A and Sephadex G-100 and added to the culture medium of mature muscle cultures from animals affected by glycogenosis type II. The enzyme activity in homogenates of treated cultures was significantly increased within 4 h of the addition of enzyme, was maximal by 18 h and the internalised activity was stable for at least 48 h after the removal of the enzyme from the culture medium. The acid alpha-glucosidase activity was internalised with an uptake constant of 300 nM and a Vmax of uptake of 133 nmol/h per mg protein. The glycogen concentration in affected cultures treated with exogenous acid alpha-glucosidase for 24 h had decreased by 20% and after a further 24 h of culture was comparable to the concentration observed in cultures from non-affected animals.
Pathological and biochemical data are reported on a 4(4)/12-year-old male patient with a severe myopathic disorder, hepatomegaly, recurrent pulmonary infections ending fatally. Combined morphological and enzymatic studies on muscle biopsy led to the diagnosis of acid maltase deficiency (Type II glycogenosis). On post mortem examination, lysosomal glycogen storage is found in skeletal muscles and liver, while heart and central nervous sytem are spared. Both hydrolytic and transferase activities of acid maltase are absent in cultured fibroblasts, heart, liver and postmortem skeletal muscles. That in the biopsied skeletal muscle only, the transferase activity alone is deficient while the hydrolytic function is maintained at low normal levels correlates well with the abnormal structure of the glycogen stored in that muscle. However, these findings on biopsied muscle cannot be reconciled with the absence of both functions and the presence of normal glycogen in other biopsied tissues or in postmortem specimens from the same patient.