Mitochondrial abnormalities in the myofibrillar myopathies
S Jackson1, J Schaefer1, M Meinhardt2
1Department of Neurology, Technische Universität Dresden, Dresden, Germany.
European Journal of Neurology
|July 25, 2015
Summary
Myofibrillar myopathies involve genetic skeletal muscle disorders. While abnormal mitochondrial distribution is common, specific markers like COX-negative fibers are rare across subtypes.
Area of Science:
- Neurology
- Genetics
- Cell Biology
Background:
- Myofibrillar myopathies (MFMs) are a heterogeneous group of skeletal muscle disorders.
- Genetic mutations in Z-disc proteins (e.g., MYOT, TTN) cause MFMs.
- Mitochondrial abnormalities are reported in MFM patients.
Purpose of the Study:
- To review the literature on mitochondrial dysfunction in MFM subtypes.
- To assess the prevalence and characteristics of mitochondrial abnormalities in MFMs.
Main Methods:
- Literature review of studies on myofibrillar myopathies.
- Analysis of reported mitochondrial findings in MFM patient muscle biopsies.
Main Results:
- Abnormal mitochondrial distribution is a frequent observation in all MFM subtypes.
- COX-negative fibers and ragged red fibers, typical of mitochondrial myopathies, are rarely found in MFMs.
- Limited in vitro studies exist on mitochondrial function in MFM patients.
Conclusions:
- Mitochondrial distribution is frequently altered in MFMs, but classical mitochondrial myopathy histopathology is uncommon.
- Further research is needed to understand the functional impact of mitochondrial changes in MFMs.
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