Myoglobinopathy is an adult-onset autosomal dominant myopathy with characteristic sarcoplasmic inclusions

Nat Commun. 2019 Mar 27;10(1):1396. doi: 10.1038/s41467-019-09111-2.

Abstract

Myoglobin, encoded by MB, is a small cytoplasmic globular hemoprotein highly expressed in cardiac myocytes and oxidative skeletal myofibers. Myoglobin binds O2, facilitates its intracellular transport and serves as a controller of nitric oxide and reactive oxygen species. Here, we identify a recurrent c.292C>T (p.His98Tyr) substitution in MB in fourteen members of six European families suffering from an autosomal dominant progressive myopathy with highly characteristic sarcoplasmic inclusions in skeletal and cardiac muscle. Myoglobinopathy manifests in adulthood with proximal and axial weakness that progresses to involve distal muscles and causes respiratory and cardiac failure. Biochemical characterization reveals that the mutant myoglobin has altered O2 binding, exhibits a faster heme dissociation rate and has a lower reduction potential compared to wild-type myoglobin. Preliminary studies show that mutant myoglobin may result in elevated superoxide levels at the cellular level. These data define a recognizable muscle disease associated with MB mutation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • European Continental Ancestry Group / genetics
  • Female
  • Heart Failure / etiology
  • Heme / metabolism
  • Humans
  • Inclusion Bodies / pathology*
  • Male
  • Middle Aged
  • Muscle Fibers, Skeletal / pathology*
  • Muscle Weakness / genetics*
  • Muscle Weakness / physiopathology
  • Muscle, Skeletal / diagnostic imaging
  • Muscle, Skeletal / physiopathology
  • Muscular Diseases / diagnostic imaging
  • Muscular Diseases / genetics*
  • Muscular Diseases / pathology
  • Muscular Diseases / physiopathology
  • Mutation
  • Myocytes, Cardiac / pathology*
  • Myoglobin / genetics*
  • Oxygen / metabolism
  • Pedigree
  • Respiratory Insufficiency / etiology
  • Superoxides / metabolism
  • Tomography, X-Ray Computed

Substances

  • Myoglobin
  • Superoxides
  • Heme
  • Oxygen