Monocarboxylate transporters and mitochondrial creatine kinase protein content in McArdle disease

McArdle disease (MD) is a metabolic myopathy due to myophosphorylase deficiency. We examined monocarboxylate transporters (MCT) and creatine kinase (CK) protein content in skeletal muscle from MD patients and age-matched controls to evaluate potential cellular adaptations that compensate for the loss of glycogenolysis. Our findings of higher MCT1 and mitochondrial CK suggest that proteins related to extra-muscular fuel uptake and intra-muscular energy transduction are up-regulated without change in mitochondrial mass in MD patients. ► McArdle disease (MD) is a metabolic myopathy due to myophosphorylase deficiency. ► MD patients have higher MCT1 and mitochondrial CK (mtCK) in skeletal muscle. ► Up-regulation of MCT1 and mtCK may compensate for impaired glycogenolysis.