Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0015672 (fatigue)
 51,768 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Glycogen storage disease type II (GSD II) is an inherited progressive muscle disease in which lack of functional acid alpha-glucosidase (AGLU) results in lysosomal accumulation of glycogen. We report on the impact of a null mutation of the acid alpha-glucosidase gene (AGLU(-/-)) in mice on the force production capabilities, contractile mass, oxidative capacity, energy status, morphology, and desmin content of skeletal muscle. Muscle function was assessed in halothane-anesthetized animals, using a recently designed murine isometric dynamometer. Maximal torque production during single tetanic contraction was 50% lower in the knockout mice than in wild type. Loss of developed torque was found to be disproportionate to the 20% loss in muscle mass. During a series of supramaximal contraction, fatigue, expressed as percentile decline of developed torque, did not differ between AGLU(-/-) mice and age-matched controls. Muscle oxidative capacity, energy status, and protein content (normalized to either dry or wet weight) were not changed in knockout mice compared to control. Alterations in muscle cell morphology were clearly visible. Desmin content was increased, whereas alpha-actinin was not. As the decline in muscle mass is insufficient to explain the degree in decline of mechanical performance, we hypothesize that the large clusters of noncontractile material present in the cytoplasm hamper longitudinal force transmission, and hence muscle contractile function. The increase in muscular desmin content is most likely reflecting adaptations to altered intracellular force transmission.
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PMID:Impaired performance of skeletal muscle in alpha-glucosidase knockout mice. 1211 77

Pompe's disease is an autosomal recessive myopathy. The characteristic lysosomal storage of glycogen is caused by acid alpha-glucosidase deficiency. Patients with late-onset Pompe's disease present with progressive muscle weakness also affecting pulmonary function. In search of a treatment, we investigated the feasibility of enzyme replacement therapy with recombinant human alpha-glucosidase from rabbit milk. Three patients (aged 11, 16, and 32 years) were enrolled in the study. They were all wheelchair-bound and two of them were ventilator dependent with a history of deteriorating pulmonary function. After 3 years of treatment with weekly infusions of alpha-glucosidase, the patients had stabilized pulmonary function and reported less fatigue. The youngest and least affected patient showed an impressive improvement of skeletal muscle strength and function. After 72 weeks of treatment, he could walk without support and finally abandoned his wheelchair. Our findings demonstrate that recombinant human alpha-glucosidase from rabbit milk has a therapeutic effect in late-onset Pompe's disease. There is good reason to continue the development of enzyme replacement therapy for Pompe's disease and to explore further the production of human therapeutic proteins in the milk of mammals.
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PMID:Enzyme replacement therapy in late-onset Pompe's disease: a three-year follow-up. 1504 88

Late-onset Pompe's disease (acid maltase deficiency, glycogen storage disease type II) is a slowly progressive myopathy caused by deficiency of acid alpha-glucosidase. Current developments in enzyme replacement therapy require detailed knowledge of the kind and severity of symptoms and the natural course of the disease in the patient population. A detailed questionnaire covering the patients' medical history and current situation was developed and information was gathered from 54 Dutch patients. The mean age of the participants was 48.6 +/- 15.6 years. The first complaints started at a mean age of 28.1 +/- 14.3 years and were mostly related to mobility problems and limb-girdle weakness. Fifty-eight percent of the adult patients indicated the presence of mild muscular symptoms during childhood. Twenty-eight percent of the patients waited >5 years for the final diagnosis after the first visit to a physician for disease-related complaints. At the time of questionnaire completion, 48% of the study population used a wheelchair and 37% used artificial ventilation. Movements such as rising from an armchair, taking stairs or getting upright after bending over were difficult or impossible for more than two-thirds of the respondents. The age at onset, the rate of disease progression and the sequence of respiratory and skeletal muscle involvement varied substantially between patients. Seventy-six percent of the participants indicated being troubled by fatigue and 46% by pain. This survey has mapped the age at onset, presenting symptoms, heterogeneity in progression and range of disease severity in a large group of Dutch patients. We conclude that early manifestations in childhood require proper attention to prevent unnecessary delay of the diagnosis. The follow-up of patients with late-onset Pompe's disease should focus on respiratory and limb-girdle muscle function, the capacity to perform daily activities, and the presentation of fatigue and pain.
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PMID:Clinical manifestation and natural course of late-onset Pompe's disease in 54 Dutch patients. 1565 25

We report a 25-year-old man with glycogenosis III who presented with a progressive 2 year history of fatigue, hand stiffness and cramping. The glycogenoses are a group of rare metabolic disorders which develop as a result of deficiencies in various enzymes involved in the metabolism of glycogen. Some, but not all, glycogenoses, may result in skeletal muscle pathology. Among those that result in vacuolar myopathic changes, glycogen storage disease III or debrancher enzyme deficiency, an autosomal recessive condition, is less commonly encountered than acid maltase (Type II) and myophosphorylase (Type V) deficiencies. Many patients with debrancher enzyme deficiency also have liver involvement. The neurological examination of our patient showed mild proximal limb weakness and decreased reflexes. He had elevated creatine kinase and aldolase levels. He also demonstrated some elevations in his liver function tests, suggesting possible liver involvement. A skeletal muscle biopsy demonstrated vacuolar myopathic changes (acid phosphatase negative) accompanied by focal endomysial fibrosis and chronic inflammation. An ultrastructural examination showed that his vacuoles were filled with glycogen material. An enzyme assay of skeletal muscle tissue showed a significant decrease in debrancher enzyme activity (11% of normal). We review the typical clinical presentation of patients with glycogenosis III and discuss the differential diagnoses of glycogenosis III versus the other glycogenoses resulting in vacuolar myopathy.
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PMID:Pathological characteristics of glycogen storage disease III in skeletal muscle. 2606 41