Key words: Glycogenosis II, GSDII, Pompe disease Glycogenosis II (GSD II; Pompe’s disease; OMIM entry # 232300) is a storage disorder resulting from a deficiency of acid alpha-glucosidase, which is the only enzyme able to ZD1839 ic50 process glycogen into lysosomes. Enzyme deficiency leads to accumulation of glycogen in muscles, lysosomal disruption and excess of autophagic vesicle buildup inside

the myofibers, causing progressive cardiac, motor and respiratory failure (1). GSD II can be clinically divided into two main subtypes. The infantile form usually appears in the first month of life, presents with severe cardiac involvement Inhibitors,research,lifescience,medical and total deficiency of alpha-glucosidase activity (< 1% of normal controls), Inhibitors,research,lifescience,medical and progresses rapidly; the late-onset form is characterized by phenotypical variability even though the main findings are progressive muscle weakness and severe respiratory insufficiency (2, 3). Limb-girdle weakness is frequently the early sign of the late-onset disease. Patients usually report difficulty in walking and running, playing sports, climbing stairs or rising from a chair. Severe

weakness may also be observed in paraspinal muscles and additional neuromuscular features may include scapular winging and distal contractures. Inhibitors,research,lifescience,medical Respiratory muscles are always involved with weakness of the diaphragm, intercostal and Inhibitors,research,lifescience,medical accessory muscles whereas the cardiac damage is usually less severe (2). Muscle weakness and limited movement, especially of the antigravity muscles, may lead to alterations of posture, severe scoliosis and lumbar hyperlordosis, which entail biomechanical disadvantages, muscle contractures and deformity in a vicious circle of progressive disability. Increasing evidence shows that systemic abnormalities are present in GSDII Inhibitors,research,lifescience,medical patients and several tissues other than muscles may be involved in the course of the disease; therefore GSD II should be regarded as a multisystem disorder in which glycogen accumulation is present

in skeletal and smooth muscle, heart, liver, kidney, spleen, salivary glands, glial cells, brainstem nuclei, anterior horn cells of spinal cord and blood vessels (2). In this review we briefly summarize the non-skeletal muscle targets of the pathological selleck chemical process in late-onset GSD II. Nervous system involvement In Pompe mice, mass spectrometric quantification showed that glycogen progressively accumulates in brain (4). In pathological studies, glycogen storage was detected in cell bodies throughout the gray matter of the spinal cord, in cerebrum and cerebellum neurons, in glial and Schwann cells (5). Interestingly, animal models clearly showed glycogen accumulation in spinal and medullary respiratory neurons (6, 7). Glycogen storage was especially noted in phrenic motoneurons which also had larger soma area compared with wild-type controls (6).