Disease relevance of Mitochondrial Encephalomyopathies

• We observed a deficiency of both the mitochondrial and cytosolic forms of fumarase in a male infant with mitochondrial encephalomyopathy who presented at one month of age with failure to thrive, developmental delay, hypotonia, cerebral atrophy, lactic and pyruvic acidemia, and fumaric aciduria [1].
• The mitochondrial tRNA(Leu(UUR)) mutation in mitochondrial encephalomyopathy, lactic acidosis, and strokelike episodes (MELAS): genetic, biochemical, and morphological correlations in skeletal muscle [2].
• Skeletal muscle mtDNA of three patients with mitochondrial encephalomyopathy, characterized clinically by myoclonic epilepsy and ragged-red fiber (MERRF) syndrome, has been sequenced to determine the underlying molecular defect(s) [3].
• Acute renal failure and the MELAS syndrome, a mitochondrial encephalomyopathy [4].
• We describe a family with three cases of "clinically incomplete mitochondrial encephalomyopathy, lactic acidosis, and strokelike episodes (MELAS) syndrome" in which heteroplasmic tRNA(Leu(UUR)) mutation at nucleotide 3243 of the mitochondrial DNA was present in three generations [5].

Psychiatry related information on Mitochondrial Encephalomyopathies

• HMPAO-SPECT imaging resembling Alzheimer-type dementia in mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) [6].
• We describe a 16-year-old Japanese girl with a mitochondrial encephalomyopathy who presented with progressive dementia, limb weakness and atrophy, episodic vomiting, generalized convulsions, myoclonic seizures, and hypertrophic cardiomyopathy [7].

High impact information on Mitochondrial Encephalomyopathies

• Fumarase deficiency: a new cause of mitochondrial encephalomyopathy [1].
• Impairment of mitochondrial transcription termination by a point mutation associated with the MELAS subgroup of mitochondrial encephalomyopathies [8].
• Mitochondrial leucine tRNA mutation in a mitochondrial encephalomyopathy [9].
• Mitochondrial encephalomyopathy and complex III deficiency associated with a stop-codon mutation in the cytochrome b gene [10].
• An mtDNA mutation in the initiation codon of the cytochrome C oxidase subunit II gene results in lower levels of the protein and a mitochondrial encephalomyopathy [11].

Chemical compound and disease context of Mitochondrial Encephalomyopathies

• Muscle coenzyme Q deficiency in familial mitochondrial encephalomyopathy [12].
• A deficiency of succinate dehydrogenase is a rare cause of mitochondrial encephalomyopathy [13].
• Mitochondrial encephalomyopathy with coenzyme Q10 deficiency [14].
• Supplementation with creatine monohydrate in children with mitochondrial encephalomyopathies [15].
• Abnormal excretion of urinary phospholipids and sulfatide in patients with mitochondrial encephalomyopathies [16].

Biological context of Mitochondrial Encephalomyopathies

• We report on 4 male patients with clinical, radiological, and muscle biopsy findings typical of the mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) phenotype [17].
• Apoptosis and ROS detoxification enzymes correlate with cytochrome c oxidase deficiency in mitochondrial encephalomyopathies [18].
• Evoked potentials were studied in a patient with a mitochondrial encephalomyopathy revealing a defect of nicotinamideadenine dinucleotide dehydrogenase and cytochrome C oxidase in the mitochondria of a muscle biopsy specimen [19].
• The clinical findings of mitochondrial encephalomyopathy should be reinvestigated in terms of the mitochondrial gene mutation; the polymerase chain reaction method will be useful for screening for this mutation of mitochondrial DNA in blood samples [20].
• A mitochondrial encephalomyopathy with cardiomyopathy. A case revealing a defect of complex I in the respiratory chain [7].

Anatomical context of Mitochondrial Encephalomyopathies

• Coenzyme Q10 (CoQ) content was measured in isolated muscle mitochondria from 25 patients with mitochondrial encephalomyopathies (MEM), most of whom had mitochondrial DNA mutations [21].
• The populations of cytochrome c oxidase (CCO)-positive and -negative mitochondria were analyzed in the elongated cells containing occasional multiple nuclei (myotubes) in primary muscle cultures derived from patients with various forms of mitochondrial encephalomyopathies with CCO deficiency [22].
• Cerebrospinal fluid neurone-specific enolase in mitochondrial encephalomyopathies [23].
• Corneal endothelium in a case of mitochondrial encephalomyopathy (Kearns-Sayre syndrome) [24].
• Focal cytochrome c oxidase deficiency in the brain and dorsal root ganglia in a case with mitochondrial encephalomyopathy (tRNA(Ile) 4269 mutation): histochemical, immunohistochemical, and ultrastructural study [25].

Gene context of Mitochondrial Encephalomyopathies

• A mutation in the tRNA(Leu)(UUR) gene associated with the MELAS subgroup of mitochondrial encephalomyopathies [26].
• OBJECTIVES: Mitochondrial cytopathies such as Leber's hereditary optic neuropathy (LHON), mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS), and myoclonus epilepsy with red ragged fibers (MERRF) are associated with distinct mtDNA point mutations (for review see 1) [27].
• Dysfunction of mitochondrial ATPase (F1F(o)-ATP synthase) due to missense mutations in ATP6 [mtDNA (mitochondrial DNA)-encoded subunit a] is a frequent cause of severe mitochondrial encephalomyopathies [28].
• BACKGROUND: Cerebral infarction is a known complication in patients with mitochondrial encephalomyopathies (MELAS, MERRF, Kearns-Sayre syndrome), but the etiology in the different types remains uncertain [29].
• BACKGROUND: The mitochondrial DNA gene encoding subunit 5 of complex I (ND5) has turned out to be a hot spot for mutations associated with mitochondrial encephalomyopathy with lactic acidosis and strokelike episodes (MELAS) and various overlap syndromes [30].

Analytical, diagnostic and therapeutic context of Mitochondrial Encephalomyopathies

• Single-photon emission computed tomography (SPECT) of the brain using hexamethyl propylene amine oxime (HMPAO) was performed in a 37-year-old patient suffering from mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) [6].
• The localization and amounts of myoglobin (Mb) and Mb mRNA in ragged-red fibers (RRF) in skeletal muscle of 6 patients with mitochondrial encephalomyopathy were examined immunohistochemically and by in situ hybridization [31].
• Coenzyme Q10 treatment in mitochondrial encephalomyopathies. Short-term double-blind, crossover study [32].
• Regional brain glucose metabolism has been studied in a case of mitochondrial encephalomyopathy with ragged red fibers, using positron emission tomography with fluorodeoxyglucose as the tracer [33].
• The therapeutic efficacy of a regimen consisting of intravenous injection of Cardiocrome, containing cytochrome c, flavin mononucleotide and thiamine diphosphate for mitochondrial encephalomyopathy (MEM) was examined [34].

References