Contribution of muscle biopsy and genetics to the diagnosis of chronic progressive external opthalmoplegia of mitochondrial origin

Mitochondrial dysfunction in inherited renal disease and acute kidney injury

“…Morphological analyses coupled with histochemical staining enables the detection of COX-deficient fibres and mitochondrial proliferation 104 . A uniform pattern points to a nDNA defect, whereas a mosaic distribution (owing to heteroplasmy) is suggestive of a mtDNA abnormality, which can occur as a result of a mutation in mtDNA or as a secondary effect of a mutation in a nuclear mtDNA maintenance gene.…”

Clinical, biochemical, molecular, and histological features of 65 Portuguese patients with mitochondrial disorders

“…Mitochondrial disorders are a highly heterogeneous group of disorders, and chronic progressive external ophthalmoplegia (CPEO) is the most frequent and typical presentation . Mitochondrial dysfunction in these disorders is the result of changes in the mitochondrial genome or in nuclear DNA (nDNA) genes that code for mitochondrial proteins or interact with mitochondrial DNA (mtDNA).…”

“…neous group of disorders, and chronic progressive external ophthalmoplegia (CPEO) is the most frequent and typical presentation. [1][2][3] Mitochondrial dysfunction in these disorders is the result of changes in the mitochondrial genome or in nuclear DNA (nDNA) genes that code for mitochondrial proteins or interact with mitochondrial DNA (mtDNA). Over 85% of all mitochondrial proteins are encoded by nDNA, although only a small number of disease-causing nDNA genes have been identified.…”

Automated Methods for the Analysis of Skeletal Muscle Fiber Size and Metabolic Type

“…With time, the conditions for histochemical staining of enzymatic activity were optimized and many investigators contributed to this development. The sequential evaluation of SDH/COX activities in the same muscle section is currently a predominant method for histological evaluation of mitochondrial dysfunction (discussed in Section 7.1) (Barron et al, 2005;Greaves et al, 2010;Sundaram et al, 2011;Taivassalo et al, 2012;Vladutiu and Heffner, 2000). Blanco et al (1988) described histochemical technique for quantitative determination of SDH activity in muscle sections; this was reevaluated by Powers et al (1993) who concluded that the method was both valid and reliable in the determination of SDH activity in skeletal muscle fibers.…”