Chronic progressive external ophthalmoplegia (CPEO): clinical, morphologic, and biochemical studies.
We studied skeletal muscles from eight chronic progressive external ophthalmoplegia patients with ragged-red fibers (group A), five CPEO patients without ragged-red fibers (group B), and five controls. The EM morphometric fraction of structurally abnormal mitochondria was increased in group A, and there was a similarly increased fraction of normal-appearing mitochondria in group B. State 3 respiration and uncoupled respiration were severely decreased in both groups. The morphometric mitochondrial fraction and respiratory functions were inversely related in all three groups. The cytochrome content in group A was normal; cytochromes b and cc1 were decreased in group B. These studies point to a central role of mitochondrial dysfunction in all types of CPEO, but the basic abnormalities remain to be elucidated.
D000328:Adult; D002648:Child; D003573:Cytochrome b Group / Q000032:analysis / Q000378:metabolism; D003574:Cytochrome c Group / Q000032:analysis / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008931:Mitochondria, Muscle / Q000378:metabolism / Q000648:ultrastructure; D009124:Muscle Proteins / Q000032:analysis; D009132:Muscles / Q000378:metabolism / Q000473:pathology* / Q000648:ultrastructure; D009886:Ophthalmoplegia / Q000378:metabolism / Q000473:pathology*
D003573:Cytochrome b Group; D003574:Cytochrome c Group; D009124:Muscle Proteins