Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0013421 (dystonia)
 8,418 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The cause and pathophysiology of dystonia remain unknown. The recent identification of mitochondrial complex I deficiency in platelets from patients with sporadic focal dystonia suggests that a defect of energy metabolism may be relevant in a proportion of patients. We have addressed the possible contribution of mitochondrial DNA (mtDNA) to the complex I deficiency in dystonia by the use of genome transfer technology. Platelets from patients deficient for complex I were fused with A549 p0 (mtDNA-less) cells to form cybrids comprising the A549 nucleus and dystonia mtDNA. Mixed cybrid cell lines were analyzed for 9 controls and 9 dystonia patients, and clonal cybrid lines were generated for 2 control and 2 dystonia patients. Subsequent biochemical analysis showed that the dystonia complex I defect was complemented in both the mixed and the clonal cybrid lines. These results contrast with similar studies in mitochondrial myopathy and Parkinson's disease patients, in which the mitochondrial defect was maintained in at least a proportion of A549 cybrids, and suggest that the complex I defect in dystonia is not caused by an mtDNA mutation.
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PMID:Mitochondrial DNA in focal dystonia: a cybrid analysis. 970 50

Mitochondria play a critical role in cellular energy metabolism. The identification of a respiratory chain defect in Parkinson's disease (PD) provides not only a direct link with toxin models of parkinsonism but also insight into the mechanisms involved in etiology and pathogenesis. The presence of the complex I deficiency in PD substantia nigra and platelets suggests the involvement of a systemic cause. Genomic transplantation studies have been undertaken that involve the transfer to a novel nuclear background of mitochondrial DNA (mtDNA) from PD patients with a complex I defect, followed by both mixed and clonal expansion of the resulting cybrids. The mixed cybrids with the PD mtDNA expressed the complex I defect present in the original PD donor platelets. Clonal expansion of one such mixed cybrid culture produced a spectrum of clones with complex I and complex IV activities, ranging from severe deficiency to normal range, a pattern typical of a heteroplasmic mtDNA mutation. Histochemical, immunohistochemical, and functional assessments of delta psi(m) all showed a pattern in the PD clones typical of that produced by a mtDNA mutation. Patients with focal dystonia and a platelet complex I defect were used as disease controls for the cybrid studies. The mitochondrial abnormality was eradicated by transfer of dystonia mtDNA to a control nuclear background in both mixed and clonal cybrids, with no evidence of clonal heterogeneity. These results help to validate our findings in the PD patients and suggest that the complex I deficiency in dystonia is not due to an abnormality of mtDNA. We hypothesize that the mtDNA defect alone may be the cause of PD in a proportion of patients and may contribute to pathogenesis in others. Identification of the mtDNA genotype responsible for PD may allow the testing of neuroprotective strategies in appropriate patients.
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PMID:Mitochondria in the etiology and pathogenesis of Parkinson's disease. 974 79

Leigh syndrome is a form of neurodegenerative disease which is associated with intracranial infarcts. The diagnosis is made by finding hyperlactacidaemia together with cerebral infarcts on neuroimaging. We report a 4-year-old Chinese girl with Leigh syndrome who had several atypical features. She presented with generalized dystonia and developmental regression. In addition, she suffered from an unusual feature of bladder dystonia. This patient appeared to be suffering from respiratory chain complex I deficiency from studies on cultured skin fibroblasts. Assays for respiratory chain enzymes as well as mitochondrial DNA point mutations and major deletions in muscle were normal. Dystonia persisted despite treatments with muscle relaxants and a ketogenic diet. Intramuscular botulinum toxin resulted in significant relief of dystonia.
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PMID:A Chinese girl with Leigh syndrome: effect of botulinum toxin on dystonia. 976 17

Idiopathic Parkinson's disease involves the loss of midbrain dopaminergic neurons, resulting in the presynaptic breakdown of dopaminergic transmission in the striatum. Huntington's disease and some neurodegenerative diseases with Parkinsonian features have postsynaptic defects caused by striatal cell death. Mice were generated in which an attenuated form of the diphtheria toxin gene (tox-176) was expressed exclusively in D1 dopamine receptor (D1R)-positive cells with the aim of determining the effect of this mutation on development of the basal ganglia and on the locomotor phenotype. Transgenic mice expressing Cre, a site-specific DNA recombinase, were crossed with a second line in which a transcriptionally silenced tox-176 gene was inserted into the D1R gene locus by homologous recombination. Young doubly transgenic mutant mice expressing the tox-176 gene displayed bradykinesia, dystonia, and had falls caused by myoclonic jerks. The mutant brain had evidence of apoptosis and reactive gliosis and, consistent with the D1R expression pattern, the striatum was reduced in volume, and the Islands of Calleja were absent. In contrast, the cortex was of normal thickness. D1Rs were not detectable in mutants by in situ hybridization or ligand autoradiography, whereas D2 dopamine receptor (D2R) mRNA and protein was present in the striatum. In addition, substance P and dynorphin, neuropeptides known to be expressed in D1R-positive striatonigral projection neurons were not detectable. Enkephalin, a marker found in D2-positive striatopallidal projection neurons was expressed in the mutant brain. The mutant represents a novel neurodegenerative disease model with a dramatic extrapyramidal phenotype.
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PMID:Targeted expression of a toxin gene to D1 dopamine receptor neurons by cre-mediated site-specific recombination. 982 43

Some patients with an 18p- syndrome show dystonia, and a focal dystonia gene has been mapped to chromosome 18p. The authors evaluated the extent of the deletion in three patients with an 18p- syndrome and dystonia using 14 DNA markers on 18p. A common deleted area, covering the DYT7 locus, places the putative dystonia gene between the telomere of 18p and D18S1104 (49.6 cM). Dystonia in these patients may be caused by haploinsufficiency of the DYT7 gene, a new dystonia gene on 18p, or may result from developmental brain anomalies.
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PMID:Genetic analysis of three patients with an 18p- syndrome and dystonia. 1002 8

A variety of neurologic phenotypes have been described in patients with mitochondrial disorders. We report a 32-year-old man in whom dystonia was the salient and presenting feature of a mitochondrial DNA mutation. He presented at age 23 with writer's cramp and progressed over 5 years to exhibit dystonia in facial muscles and lower limbs. He also has exercise intolerance, mild, bilateral ptosis, proximal muscle weakness, and sensorineural hearing loss. Molecular genetic analysis of blood, urine, and muscle biopsy demonstrated the presence of a heteroplasmic point mutation at nucleotide position 3243. The 3243 mtDNA mutation has pleomorphic manifestations, and dystonia should be added to the list of associated clinical features.
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PMID:Dystonia as a presenting feature of the 3243 mitochondrial DNA mutation. 1034 75

A white Italian family affected by primary torsion dystonia (PTD) is described. The family phenotype most commonly presented with adult onset, cranial cervical involvement, and focal or segmental distribution without progression to generalization. Thirty-nine family members and nine spouses were studied. Five subjects received a diagnosis of definite PTD, three of probable PTD. Age at onset was in adulthood for all. In four definitely affected subjects, dystonia started in the cranial or cervical districts; in one it presented as writer's cramp. Familial writer's cramp also occurred in the family of the unrelated parent of the latter patient. The mean age at time of examination was 61.8 years in the individuals with a definite diagnosis; 60 in those with a probable diagnosis. At the time of examination, in most of the affected subjects, dystonia was focal; in three cases (two definitely and one probably affected), it was segmental. DNA linkage analysis, although limited by the size of the family, suggested exclusion of linkage between the disease and known PTD loci (DYT6 and DYT7). The GAG deletion in the DYT1 gene was excluded in the proband and in the family member affected by writer's cramp.
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PMID:Italian family with cranial cervical dystonia: clinical and genetic study. 1049 44

We reported a 10-year-old boy with congenital plasminogen abnormality resulting in recurrent cerebrovascular ischemic attacks. He suddenly developed dystonia of the left upper limb at 9 years of age. MRI demonstrated small infarcts in the right thalamus and caudate nucleus. He then had a transient ischemic attack at 10 years. He complained of headache, vertigo, diplopia, and unsteady gait. DNA analysis revealed that he was heterozygotic for abnormal plasminogen. Thus, congenital plasminogen abnormality was suspected to be a cause of recurrent cerebrovascular ischemic attacks in this case.
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PMID:[A case of congenital plasminogen abnormality with recurrent cerebrovascular ischemic attacks]. 1056 90

We present a boy of eight years of age with symptoms of Kearns-Sayre syndrome (KSS) characterised by ophthalmoparesis, palpebral ptosis, mitochondrial myopathy, pigmentous retinitis, associated to short stature, cerebellar signs, cardiac blockade, diabetes mellitus, elevated cerebrospinal fluid protein concentration, and focal hand and foot dystonia. The skeletal muscle biopsy demonstrated ragged red fibers, cytochrome C oxidase-negative and succinate dehydrogenase-positive fibers. The magnetic resonance imaging showed symmetrical signal alteration in tegmentum of brain stem, pallidum and thalamus. Mitochondrial DNA analysis from skeletal muscle showed a deletion in heteroplasmic condition. The association of dystonia to KSS, confirmed by molecular analysis, is first described in this case, and the importance of oxidative phosphorylation defects in the physiopathogenesis of this type of movement disorder is stressed.
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PMID:Kearns-Sayre syndrome "plus". Classical clinical findings and dystonia. 1068 96

Glutaric acidemia type I (GAI) is an autosomal recessive organic acidemia caused by a mutation in the gene encoding glutaryl-CoA dehydrogenase (GCD). Clinically, GAI is characterized by progressive dystonia, resulting from degeneration of neurons in the caudate and putamen nuclei of the striatum. In an attempt to understand the basis for the specific neuropathology in GAI, we have analyzed the expression of the murine GCD gene using both in vitro and in vivo approaches. Transfection studies mapped the mouse GCD promoter to a 500-bp region of DNA 5' of the translation start site. The promoter lacks a TATA consensus sequence, but includes possible binding sites for several transcription factors with roles in the regulation of nuclear genes encoding mitochondrial proteins. Western blot and RT/PCR analyses of mouse tissues demonstrated that GCD is ubiquitously expressed, with the highest levels of expression in liver and kidney, consistent with its role in amino acid oxidation. Expression in multiple regions of the brain was also detected by Western blotting. Based on these results we conclude that the specific neuropathology associated with GCD deficiency in GAI cannot be accounted for by its expression pattern.
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PMID:Analysis of the expression of murine glutaryl-CoA dehydrogenase: in vitro and in vivo studies. 1072 Apr 38


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