Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030567 (Parkinson's disease)
 63,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Decreased mitochondrial Complex I activities and a 4,977-bp deletion in mitochondrial DNA (mtDNA) have been reported in patients with Parkinson's disease. Based on the assumption of possible links between this 4,977-bp deletion and the etiology of Parkinson's disease, we analyzed mtDNA of blood cells from 15 patients with young-onset Parkinson's disease after the DNA was amplified by polymerase chain reaction. We could not detect the 4,977-bp mtDNA deletion in any of these patients. This result suggests that Parkinson's disease is not a mitochondrial disease due to the 4,977-bp mtDNA deletion. The 4,977-bp deletion in mtDNA appears to be an age-related phenomenon.
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PMID:Absence of 4,977-bp deletion of blood cell mitochondrial DNA in patients with young-onset Parkinson's disease. 778 27

Virtually all cells in humans depend on mitochondrial oxidative phosphorylation to generate energy, accounting for the remarkable diversity of clinical disorders associated with mitochondrial DNA mutations. However, certain tissues are particularly susceptible to mitochondrial dysfunction, resulting in recognizable clinical syndromes. Mitochondrial DNA mutations have been linked to seizures, strokes, optic atrophy, neuropathy, myopathy, cardiomyopathy, sensorineural hearing loss, diabetes mellitus, and other clinical features. Mitochondrial DNA mutations also may play an important role in aging, as well as in common age-related neurodegenerative disorders such as Parkinson's disease. Therefore, it is becoming increasingly important for clinicians to recognize the clinical syndromes suggestive of a mitochondrial disorder, and to understand the unique features of mitochondrial genetics that complicate diagnosis and genetic counseling.
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PMID:Mitochondrial disorders: clinical and genetic features. 1007 67

Parkinson's disease is a nosological entity of unknown origin for which, in some cases, a possible pathogenetic role for mitochondrial dysfunction has been postulated. Two young onset parkinsonian patients with mitochondrial DNA (mtDNA) deletions in skeletal muscle are reported on. Patient 1 also presented with increased blood creatine kinase and lactate concentrations and a family history which included a wide range of phenotypes affecting multiple systems. Patient 2 presented with multiple symmetric lipomatosis. Histopathological investigation showed ragged red fibres and COX negative fibres in muscle biopsies from both patients. The data support the hypothesis that mitochondrial DNA mutations may occur in some cases of parkinsonism, suggesting that a diagnosis of a mitochondrial disorder should be considered in the presence of consistent family history and clinical symptoms.
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PMID:Mitochondrial DNA rearrangements in young onset parkinsonism: two case reports. 1160 86

The availability of monoclonal antibodies (mAbs) against the proteins of the oxidative phosphorylation chain (OXPHOS) and other mitochondrial components facilitates the analysis and ultimately the diagnosis of mitochondrially related diseases. mAbs against each of the five complexes and pyruvate dehydrogenase (PDH) are the basis of a rapid and simple immunocytochemical approach [Hanson, B.J., Capaldi, R.A., Marusich, M.F. and Sherwood, S.W., J. Histochem. Cytochem. 50 (2002) 1281-1288]. This approach can be used to detect if complexes have altered assembly in mitochondrial disease due to mutations in nuclear encoded genes, such as in Leigh's disease, or in mitochondrially encoded genes, e.g., MELAS. Other mAbs have recently been obtained that can immunocapture each of the five OXPHOS complexes, PDH and the adenine nucleotide translocase (ANT) from very small amounts of tissue such as that obtained from cell culture or needle biopsies from patients. When adapted to a 96-well plate format, these mAbs allow measurement of the specific activity of each of the mitochondrial components individually and analysis of their subunit composition and state of posttranslational modification. The immunocapture protocol should be useful not only in the analysis of genetic mitochondrial diseases but also in evaluating and ultimately diagnosing late-onset mitochondrial disorders including Parkinson's disease, Alzheimer's disease, and late-onset diabetes, which are thought to result from accumulated oxidative damage to mitochondrial proteins such as the OXPHOS chain.
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PMID:Focused proteomics: towards a high throughput monoclonal antibody-based resolution of proteins for diagnosis of mitochondrial diseases. 1557 53

In spite of several evidences for a mitochondrial impairment in Parkinson's disease (PD), so far it has not been possible to show in vivo mitochondrial dysfunction in the human brain of PD patients. The authors used the high temporal and spatial resolution 31 phosphorus magnetic resonance spectroscopy (31P MRS) technique, which they have previously developed in normal subjects and in patients with mitochondrial diseases to study mitochondrial function by observing high-energy phosphates (HEPs) and intracellular pH (pH) in the visual cortex of 20 patients with PD and 20 normal subjects at rest, during, and after visual activation. In normal subjects, HEPs remained unchanged during activation, but rose significantly (by 16%) during recovery, and pH increased during visual activation with a slow return to rest values. In PD patients, HEPs were within the normal range at rest and did not change during activation, but fell significantly (by 36%) in the recovery period; pH did not reveal a homogeneous pattern with a wide spread of values. Energy unbalance under increased oxidative metabolism requirements, that is, the postactivation phase, discloses a mitochondrial dysfunction that is present in the brain of patients with PD even in the absence of overt clinical manifestations, as in the visual cortex. This is in agreement with our previous findings in patients with mitochondrial disease without clinical central nervous system (CNS) involvement. The heterogeneity of the physicochemical environment (i.e., pH) suggests various degrees of subclinical brain involvement in PD. The combined use of MRS and brain activation is fundamental for the study of brain energetics in patients with PD and may prove an important tool for diagnostic purposes and, possibly, to monitor therapeutic interventions.
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PMID:Parkinson's disease and brain mitochondrial dysfunction: a functional phosphorus magnetic resonance spectroscopy study. 1609 20

The evidence supporting a treatment benefit for coenzyme Q10 (CoQ10) in primary mitochondrial disease (mitochondrial disease) whilst positive is limited. Mitochondrial disease in this context is defined as genetic disease causing an impairment in mitochondrial oxidative phosphorylation (OXPHOS). There are no treatment trials achieving the highest Level I evidence designation. Reasons for this include the relative rarity of mitochondrial disease, the heterogeneity of mitochondrial disease, the natural cofactor status and easy 'over the counter availability' of CoQ10 all of which make funding for the necessary large blinded clinical trials unlikely. At this time the best evidence for efficacy comes from controlled trials in common cardiovascular and neurodegenerative diseases with mitochondrial and OXPHOS dysfunction the etiology of which is most likely multifactorial with environmental factors playing on a background of genetic predisposition. There remain questions about dosing, bioavailability, tissue penetration and intracellular distribution of orally administered CoQ10, a compound which is endogenously produced within the mitochondria of all cells. In some mitochondrial diseases and other commoner disorders such as cardiac disease and Parkinson's disease low mitochondrial or tissue levels of CoQ10 have been demonstrated providing an obvious rationale for supplementation. This paper discusses the current state of the evidence supporting the use of CoQ10 in mitochondrial disease.
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PMID:The evidence basis for coenzyme Q therapy in oxidative phosphorylation disease. 1748 45

Nuclear genes encode most mitochondrial proteins, and their mutations cause diverse and debilitating clinical disorders. To date, 1,200 of these mitochondrial genes have been recorded, while no standardized catalog exists of the associated clinical phenotypes. Such a catalog would be useful to develop methods to analyze human phenotypic data, to determine genotype-phenotype relations among many genes and diseases, and to support the clinical diagnosis of mitochondrial disorders. Here we establish a clinical phenotype catalog of 174 mitochondrial disease genes and study associations of diseases and genes. Phenotypic features such as clinical signs and symptoms were manually annotated from full-text medical articles and classified based on the hierarchical MeSH ontology. This classification of phenotypic features of each gene allowed for the comparison of diseases between different genes. In turn, we were then able to measure the phenotypic associations of disease genes for which we calculated a quantitative value that is based on their shared phenotypic features. The results showed that genes sharing more similar phenotypes have a stronger tendency for functional interactions, proving the usefulness of phenotype similarity values in disease gene network analysis. We then constructed a functional network of mitochondrial genes and discovered a higher connectivity for non-disease than for disease genes, and a tendency of disease genes to interact with each other. Utilizing these differences, we propose 168 candidate genes that resemble the characteristic interaction patterns of mitochondrial disease genes. Through their network associations, the candidates are further prioritized for the study of specific disorders such as optic neuropathies and Parkinson disease. Most mitochondrial disease phenotypes involve several clinical categories including neurologic, metabolic, and gastrointestinal disorders, which might indicate the effects of gene defects within the mitochondrial system. The accompanying knowledgebase (http://www.mitophenome.org/) supports the study of clinical diseases and associated genes.
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PMID:Mapping gene associations in human mitochondria using clinical disease phenotypes. 1939 Jun 13

Mitochondrial dysfunction has been implicated in the pathogenesis of sporadic, idiopathic Parkinson disease. In some cases, mitochondrial DNA primary genetic abnormalities, or more commonly, secondary rearrangements due to polymerase gamma (POLG1) gene mutation, can directly cause parkinsonism. The case of a Parkinson disease patient with some signs or symptoms suggestive of mitochondrial disease (i.e., ptosis, myopathy, neuropathy) is a relatively common event in the neurological practice. Mitochondrial parkinsonisms do not have distinctive features allowing an immediate diagnosis, and a negative family history does not rule out a possible diagnosis of mitochondrial disorder. In this article, we do not revise the mitochondrial hypothesis of sporadic, idiopathic Parkinson disease, extensively discussed elsewhere, but we review POLG1-related parkinsonism and other well-defined forms of "mitochondrial parkinsonisms", with mtDNA mutations or rearrangements. Lastly, we try to introduce a possible diagnostic approach for patients with parkinsonism and suspected mitochondrial disorder.
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PMID:POLG1-related and other "mitochondrial Parkinsonisms": an overview. 2122 44

In the majority of cases, mitochondrial disorders are multisystem conditions that most frequently affect the skeletal muscle, followed by the central nervous system. One of the clinical manifestations of central nervous system involvement is Parkinson's syndrome (PS). Evidence for an association of mitochondrial defects with PS comes from mitochondrial disorder patients who have developed Parkinson's syndrome and from Parkinson's syndrome patients who have developed a mitochondrial disorder. In addition, there are a number of patients with Parkinson's syndrome or Parkinson's disease (PD) who later develop subclinical immunohistological or biochemical indications of mitochondrial defects or accumulates mitochondrial DNA mutations within various cerebral regions. There are also Parkinson's syndrome patients who present with elevated cerebrospinal-fluid lactate by magnetic resonance spectroscopy. Furthermore, it has been shown that mutations in genes causing PD, such as PINK1, parkin, DJ1, alpha-synuclein, and LRRK2, also cause mitochondrial dysfunction, which is one of the reasons why they are called mitochondrial nigropathies. Parkinson's syndrome in patients with a mitochondrial disorder may also result from oxidative stress or exogenous toxins. Treatment of mitochondrial Parkinson's syndrome is not at variance with the treatment of Parkinson's syndrome due to other causes, but because of the multisystem nature of mitochondrial disorders, mitochondrial Parkinson's syndrome requires additional therapeutic support.
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PMID:Parkinson's syndrome and Parkinson's disease in mitochondrial disorders. 2138 29

Parkinson's disease (PD), the most common movement disorder, is characterized by age-dependent degeneration of dopaminergic neurons in the substantia nigra of the mid-brain. Non-motor symptoms of PD, however, precede the motor features caused by dysfunction of the dopaminergic system, suggesting that PD is a systemic disorder. Mitochondrial dysfunction has long been observed in PD patients and animal models, but the mechanistic link between mitochondrial dysfunction and PD pathogenesis is not well understood. Recent studies have revealed that genes associated with autosomal recessive forms of PD such as PINK1 and Parkin are directly involved in regulating mitochondrial morphology and maintenance, abnormality of which is also observed in the more common, sporadic forms of PD, although the autosomal recessive PDs lack Lewy-body pathology that is characteristic of sporadic PD. These latest findings suggest that at least some forms of PD can be characterized as a mitochondrial disorder. Whether mitochondrial dysfunction represents a unifying pathogenic mechanism of all PD cases remains a major unresolved question.
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PMID:Mitochondrial dynamics and mitophagy in Parkinson's disease: disordered cellular power plant becomes a big deal in a major movement disorder. 2204 1


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