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)

Metals such as lead, zinc, copper, aluminum and manganese have been implicated in neuropsychiatric disorders. However, until fairly recently the role of iron in brain function was rather obscure, because little attention was paid to its metabolism in the brain. It is now apparent that maintenance of brain iron homoeostasis is important for the normal functioning of his organ. Most of the studies have been directed towards the cognitive and attentional deficit resulting from nutritional iron deficiency. Evidence so far suggests subsensitivity of striatal dopamine neurotransmission. By contrast the selective increase in free iron in the substantia nigra pars compacta of parkinsonian brains is thought to initiate oxidative stress, from iron-induced liberation of cytotoxic oxygen free radicals. Such radicals are known to promote membrane fluidity, alteration in cellular calcium homoeostasis, lipid peroxidation and finally cell death in systemic organs. Evidence supporting similar processes being responsible for nigrostriatal dopamine neuron degeneration in Parkinson's disease is now becoming available. Such possibilities afford the development of neuroprotective drugs as a means to retard the progression of this disorder. These include other selective monoamine oxidase B inhibitors, iron chelators with the ability to cross the blood-brain barrier, selective calcium channel antagonists and mitochondrial electron transport system protectors.
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PMID:Iron in brain function and dysfunction with emphasis on Parkinson's disease. 164 57

Iron deficiency in children is associated with retardation in growth and cognitive development, and the effects on cognition may be irreversible, even with treatment. Excessive iron has also been associated with neurological disease, especially in reference to the increased iron content in the brains of Alzheimer's disease and Parkinson's disease patients. This study evaluated the effects of dietary iron deficiency and excess iron on physical activity in rats. The animal model used is developmentally sensitive and permits control of the timing as well as the duration of the nutritional insult. Hence, to study the effects of early, late and long-term iron deficiency or excess iron (supplementation), rats were either made iron deficient or supplemented on postnatal day (PND) 10-21, PND 21-35 and PND 10-35. Some iron-deficient rats were iron repleted between PND 21-35. Different measures of motor activity were taken at PND 14, 17, 20, 27 and 34. Iron-deficient and iron-supplemented rats showed decreased activity and stereotypic behavior; this was apparent for any onset and duration of the nutritional insult. Recovery from iron deficiency did not normalize these functional variables, showing that the deleterious effects of early iron deficiency persist despite subsequent adequate treatment. This study demonstrates that iron deficiency in early life leads to irreversible behavioral changes. The biological bases for these behavioral alterations are not readily apparent, because iron therapy rapidly reverses the iron losses in all brain regions.
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PMID:Variations in dietary iron alter behavior in developing rats. 1116 May 52

Restless legs syndrome (RLS) is a sensory-motor disorder characterized by discomfort of and urge to move the legs, primarily during rest or inactivity, partial or total relief with movement, with presence or worsening exclusively in the evening. It is a relatively common but frequently unrecognized disorder, with a prevalence ranging from 2.5 to 15% of the general population, increasing with age and with a female preponderance. The diagnosis is clinical but polysomnography is useful to determine its profound impact on sleep (difficulties in sleep onset, maintaining sleep during the night, and sleep fragmentation) and for the evidence of periodic legs movements during sleep and wake. RLS is generally idiopathic, with familial association in 40-60% of the cases, but may also be symptomatic of such associated conditions (secondary forms) as peripheral neuropathies, uremia, iron deficiency (with or without anemia), diabetes, Parkinson's disease and pregnancy. Response to dopaminergic drugs indicates that dopamine receptors are implicated, and although much progress has been made in diagnosis and treatment in the last decade, more is needed for complete elucidation of the etiology and pathophysiology of RLS.
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PMID:Epidemiology and clinical findings of restless legs syndrome. 1516 38

Iron is the most important element in the body, essential for almost all types of cells, including brain cells. The role of iron in the brain has been known for years. Iron deficiency and iron excess have been associated with pathophysiology of different brain disorders. Iron deficiency has been reported to have a role in brain development and the pathophysiology of restless legs syndrome. Iron accumulation has been related to some neurologic disorders such as Alzheimer disease, Parkinson disease, type I neurodegeneration with brain iron accumulation, and other disorders. Despite years of investigation, the reason for iron imbalance in the brain is not known. It also is not known whether the accumulation of iron in the brain is primary or secondary to development of neurodegenerative disorders. This review summarizes the present knowledge on the role of iron in human brain disorders.
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PMID:Iron and brain disorders. 1529 51

In patients with Parkinson's disease, hyperechogenicity of the substantia nigra using transcranial ultrasound has been related to increased tissue concentrations of iron. Recently, deficient iron transport mechanisms in substantia nigra neurons have been described in postmortem tissue of patients with restless legs syndrome (RLS). This study was performed to study substantia nigra echogenicity in RLS patients compared with normal control subjects and Parkinson's disease patients. RLS patients had significantly reduced midbrain areas of hyperechogenicity compared with control subjects, and even more markedly reduced hyperechogenicity compared with Parkinson's disease patients. These findings lend further support to nigral iron deficiency as a pathogenetic factor in RLS.
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PMID:Transcranial ultrasound shows nigral hypoechogenicity in restless legs syndrome. 1603 73

Manganese (Mn), an element found in many foods, is an important and essential nutrient for proper health and maintenance. It is toxic in high doses, however, and exposure to excessive levels can result in the onset of a neurological disorder similar to, but distinct from, Parkinson's disease. Historically, Mn neurotoxicity was most commonly associated with various occupations, such as Mn mining, welding and steel production. More recently, increases in both blood and brain Mn levels have been observed in persons with liver disease or those receiving prolonged parenteral nutrition. Additionally, rodent data suggest that iron deficiency and anemia may be risk factors for Mn neurotoxicity. Clinically, brain Mn accumulation can be monitored in vivo using non-invasive magnetic resonance imaging (MRI) due to the paramagnetic nature of this element. Indeed, MRI has been used in a variety of settings to evaluate the brain Mn deposition in various populations. This review focuses on the use of MRI technology in studies related specifically to Mn neurotoxicity. Thus, we will examine reports using MRI to confirm brain Mn accumulation in human populations, and conclude with data from non-human primate and rodent models of Mn neurotoxicity.
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PMID:The use of magnetic resonance imaging (MRI) in the study of manganese neurotoxicity. 1662 Sep 89

Restless legs syndrome (RLS) is one of the common nocturnal disturbance seen in Parkinson's disease (PD) patients. The prevalence of RLS with PD is greater than that of general populations; however, etiology of RLS in patients with PD is still controversial. We report a 63-year-old man with PD, who was admitted to our hospital with uncontrollable unpleasant feeling in both legs leading to sleep disturbance. At age 59, he experienced numbness and nocturnal myoclonus in his right foot. One year later, he developed resting tremor and bradykinesia in his right hand, and was diagnosed as PD. Levodopa was initiated with favorable response for his resting tremor and bradykinesia, however, his dysesthesia of the legs spread to both side and associated with an urge to move which occurs at rest and was ameliorated by walking. On admission, his parkinsonism was well controlled by 400 mg/ day of levodopa/benserazide. Polysomnography (PSG) revealed periodic limb movements in sleep (PLMS). Secondary RLS such as drug-induced, iron deficiency and uraemia, was excluded in this patient. Because levodopa did not improve his RLS, additional symptomatic RLS treatment was initiated. Oral dosage with 150 microg pergolide did not have any effect on his RLS symptoms. An increase up to 750 microg pergolide led to a marked reduction of symptoms. Repeated PSG showed significant reduction of PLMS and improved sleep efficacy. Usually, low dose of dopamine agonist is enough to treat RLS occurred in general populations. However, moderate to high dose of dopamine agonists were needed for our patient with RLS, indicating that pharmacological responses might be different between RLS in general and that associated with PD. It is important to consider that PD-related RLS can be treated with high dose dopamine agonist to obtain favorable management of nocturnal disturbances.
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PMID:[Effect of high dose pergolide mesilate on restless legs syndrome associated with Parkinson disease]. 1751 Dec 86

The important function of iron as a necessary nutrition element in mammals is more and more recognized by people. The normal physiological level of iron is ensured by the rigid regulation mechanism of iron metabolism in animals. Various clinical diseases are induced by iron disorder, like iron deficiency and iron overloading in the body. The current study showed that Hepcidin may be a key factor to control intestinal iron absorbing and regulates iron homeostasis, and may be an important regulating hormone of iron metabolism. It was summarized in this paper that the physiological functions, iron deficiency diseases, for instance iron deficiency anemia and neural diseases of children, and iron overload diseases, such as liver damage, cardiovascular diseases, Parkinson's disease, and cancers etc. And it was expected how to develop the therapy of iron disorder diseases in gene level use modern techniques.
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PMID:[Progress of the study on iron disorder diseases]. 1823 99

Restless legs syndrome (RLS) has been described in association with a number of conditions including iron deficiency, neuropathy and Parkinson's disease. Here we report a patient who developed RLS concurrent with the development of classic post-polio syndrome (PPS), 40 years after recovery from an episode of paralytic poliomyelitis. PPS is still frequently encountered in neurological practice, and clinicians should be aware of the possibility of associated RLS.
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PMID:Restless legs may be associated with the post-polio syndrome. 1837 19

Restless-legs syndrome (RLS) is a sensorimotor disorder, characterized by an irresistible urge to move the legs usually accompanied or caused by uncomfortable and unpleasant sensations. It begins or worsens during periods of rest or inactivity, is partially or totally relieved by movements and is exacerbated or occurs at night and in the evening. RLS sufferers represent 2 to 3% of the general population in Western countries. Supportive criteria include a family history, the presence of periodic-leg movements (PLM) when awake or asleep and a positive response to dopaminergic treatment. The RLS phenotypes include an early onset form, usually idiopathic with a familial history and a late onset form, usually secondary to peripheral neuropathy. Recently, an atypical RLS phenotype without PLM and l-DOPA resistant has been characterized. RLS can occur in childhood and should be distinguished from attention deficit/hyperactivity disorder, growing pains and sleep complaints in childhood. RLS should be included in the diagnosis of all patients consulting for sleep complaints or discomfort in the lower limbs. It should be differentiated from akathisia, that is, an urge to move the whole body without uncomfortable sensations. Polysomnographic studies and the suggested immobilization test can detect PLM. Furthermore, an l-DOPA challenge has recently been validated to support the diagnosis of RLS. RLS may cause severe-sleep disturbances, poor quality of life, depressive and anxious symptoms and may be a risk factor for cardiovascular disease. In most cases, RLS is idiopathic. It may also be secondary to iron deficiency, end-stage renal disease, pregnancy, peripheral neuropathy and drugs, such as antipsychotics and antidepressants. The small-fiber neuropathy can mimic RLS or even trigger it. RLS is associated with many neurological and sleep disorders including Parkinson's disease, but does not predispose to these diseases. The pathophysiology of RLS includes an altered brain-iron metabolism, a dopaminergic dysfunction, a probable role of pain control systems and a genetic susceptibility with nine loci and three polymorphisms in genes serving developmental functions. RLS treatment begins with the elimination of triggering factors and iron supplementation when deficient. Mild or intermittent RLS is usually treated with low doses of l-DOPA or codeine; the first-line treatment for moderate to severe RLS is dopaminergic agonists (pramipexole, ropinirole, rotigotine). In severe, refractory or neuropathy-associated RLS, antiepileptic (gabapentin, pregabalin) or opioid (oxycodone, tramadol) drugs can be used.
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PMID:[Restless-legs syndrome]. 1865 14


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