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)

We measured brain acetylcholinesterase activity in 16 patients with Parkinson's disease (PD), 12 patients with progressive supranuclear palsy (PSP), and 13 age-matched controls, using N-methyl-4-[11C]piperidyl acetate and positron emission tomography. Kinetic analysis was performed to calculate k3, an index of acetylcholinesterase activity. In PD patients, there was a significant reduction (-17%) of cerebral cortical k3 compared with normal controls, whereas there was only a nonsignificant reduction (-10%) of cortical k3 in PSP patients. However, there was a prominent reduction (-38%) of thalamic k3 in PSP patients compared with normal controls, whereas there was only a nonsignificant reduction (-13%) of thalamic k3 in PD patients. The results suggest that there is a loss of cholinergic innervation to the cerebral cortex in association with cholinergic innervation to the thalamus in PD, whereas there is a preferential loss of cholinergic innervation to the thalamus in PSP. When the thalamic to cerebral cortical k3 ratio was taken for each subject, PD and PSP were separated, suggesting that positron emission tomography measurement of acetylcholinesterase activity may be useful for differentiating the two similar disorders.
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PMID:Positron emission tomographic measurement of acetylcholinesterase activity reveals differential loss of ascending cholinergic systems in Parkinson's disease and progressive supranuclear palsy. 1040 81

Cholinergic hyperexcitation can be induced by both acute psychological stress and exposure to acetylcholinesterase inhibitors. Both factors are known risk factors for delayed neurodeterioration processes such as Alzheimer's disease and Parkinson's disease. Recent publications on the involvement of cholinergic pathways in these and other neurodeterioration syndromes are reviewed.
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PMID:Tracking cholinergic pathways from psychological and chemical stressors to variable neurodeterioration paradigms. 1067 58

Dementia with Lewy bodies (DLB) is the second most frequent cause of primary degenerative dementias, following Alzheimer's disease (AD). The nosologic situation of this disease has fragile limits. There is controversy as to whether Parkinson's disease (PD) and DLB are two different entities or whether they make up part of the same spectrum. The terms diffuse Lewy bodies disease and the variant of Lewy bodies in senile dementia or AD have been used to describe pathologic changes with clinical manifestations of dementia and parkinsonism. At present, DLB should be understood as an entity with the essential feature being the presence of Lewy bodies in the brain stem and cerebral cortex. From the point of view of clinical examination, DLB is characterized by the presence of subcortical or progressive cortical dementia, at times without severe memory disorders, with great fluctuations and well detailed recurrent visual hallucinations. These cognitive alterations are associated with parkinsonism. Other frequent disorders are falls, syncopes, transitory alterations in consciousness, great sensitivity to neuroleptic drugs and visual illusions with pseudoperception. The correct diagnosis of this entity is important to administer adequate treatment, to avoid classical neuroleptic drugs and to establish precise prognosis. From a therapeutic point of view, cholinesterase inhibitors show some efficacy in the treatment of cognitive alterations.
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PMID:[Dementia with Lewy bodies]. 1073 62

Human brain ageing is associated with reductions in a variety of nicotinic receptors subtypes, whereas changes in age-related disorders including Alzheimer's disease or Parkinson's disease are more selective. In Alzheimer's disease, in the cortex there is a selective loss of the alpha4 (but not alpha3 or 7) subunit immunoreactivity and of nicotine or epibatidine binding but not alpha-bungarotoxin binding. Epibatidine binding is inversely correlated with clinical dementia ratings and with the level of Abeta1-42, but not related to plaque or tangle densities. In contrast, alpha-bungarotoxin binding is positively correlated with plaque densities in the entorhinal cortex. In human temporal cortex loss of acetylcholinesterase catalytic activity is positively correlated with decreased epibatidine binding and in a transgenic mouse model over expressing acetylcholinesterase, epibatidine binding is elevated. In Parkinson's disease, loss of striatal nicotine binding appears to occur early but is not associated with a loss of alpha4 subunit immunoreactivity. Tobacco use in normal elderly individuals is associated with increased alpha4 immunoreactivity in the cortex and lower densities of amyloid-beta plaques, and with greater numbers of dopaminergic neurons in the substantia nigra pars compacta. These findings indicate an early involvement of the alpha4 subunit in beta-amyloidosis but not in nigro-striatal dopaminergic degeneration.
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PMID:Nicotinic receptor subtypes in human brain ageing, Alzheimer and Lewy body diseases. 1077 Oct 16

The objective of this study was to assess the tolerability and efficacy of rivastigmine in a group of patients with probable dementia with Lewy bodies (DLB), using an open label study. Open label treatment was with rivastigmine up to maximum tolerated dose (mean 9.6 mg daily, range 3-12 mg). Eleven patients with DLB, mean age 78.5 years, were treated with this cholinesterase inhibitor. After 12 weeks of treatment, mean Neuropsychiatric Inventory scores fell by 73% for delusions, 63% for apathy, 45% for agitation and 27% for hallucinations. Five of the patients (45%) experienced very significant clinical improvements that had not been achieved with other treatments, including low dose neuroleptics. Medication was well tolerated and parkinsonian symptoms tended to improve. Cholinesterase inhibition may be a safe and effective alternative to neuroleptic treatment in DLB. Such effects may also prove to be applicable to the management of neuropsychiatric symptoms in Parkinson's disease and Alzheimer's disease.
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PMID:Rivastigmine in the treatment of dementia with Lewy bodies: preliminary findings from an open trial. 1082 36

Memantine, a non-competitive NMDA antagonist, has been approved for use in the treatment of dementia in Germany for over ten years. The rationale for use is excitotoxicity as a pathomechanism of neurodegenerative disorders. Memantine acts as a neuroprotective agent against this pathomechanism, which is also implicated in vascular dementia. HIV-1 proteins Tat and gp120 have been implicated in the pathogenesis of dementia associated with HIV infection and the neurotoxicity caused by HIV-1 proteins can be blocked completely by memantine. Memantine has been investigated extensively in animal studies and following this, its efficacy and safety has been established and confirmed by clinical experience in humans. It exhibits none of the undesirable effects associated with competitive NMDA antagonists such as dizocilpine. The efficacy of memantine in a variety of dementias has been shown in clinical trials. Memantine is considered to be a promising neuroprotective drug for the treatment of dementias, particularly Alzheimer's disease for which there is no neuroprotective therapy available currently. It can be combined with acetylcholinesterase inhibitors which are the mainstay of current symptomatic treatment of Alzheimer's disease. Memantine has a therapeutic potential in numerous CNS disorders besides dementias which include stroke, CNS trauma, Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), epilepsy, drug dependence and chronic pain. If memantine is approved by the FDA for some of these indications by the year 2005, it can become a blockbuster drug by crossing the US$1 billion mark in annual sales.
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PMID:Evaluation of memantine for neuroprotection in dementia. 1106 Jul 51

Dementia with Lewy bodies (DLB), the second most frequent cause of primary degenerative dementias following Alzheimer's disease, has been increasingly recognized since the proposal of the consensus name and clinical diagnostic criteria. Although DLB overlaps in clinical, pathological, and genetic features with Alzheimer's disease and Parkinson's disease, DLB should be understood as an entity with the essential feature of the presence of Lewy bodies in the brain stem and cerebral cortex. From the clinical point of view, DLB is characterized by the presence of progressive dementia without severe memory disorders at the early stage, with significant cognitive fluctuations, well-formed recurrent visual hallucinations, and spontaneous Parkinsonism. This article reviews recent clinical and research findings, including our own, to facilitate clinical recognition of DLB. In addition to the supportive features described in the consortium clinical diagnostic criteria for DLB such as falls and great sensitivity to neuroleptic drugs, our studies found other frequent disorders including disproportionately severe visuoconstructive and visuoperceptual disturbances, transitory alterations in consciousness with reduplication phenomena, misidentification delusions, and non-aphasic misnamings. Neuroimaging features include relatively preserved hippocampal volume on MRI and occipital involvement on metabolic and blood flow imagings. The correct diagnosis of DLB is important to administer adequate treatment, to avoid adverse effects with neuroleptic drugs, and to establish precise prognosis. The present summary of the clinical features is hopefully helpful for clinical diagnosis of DLB. From a therapeutic point of view, cholinesterase inhibitors seemingly show some efficacy in the treatment of cognitive alterations. Further research would result in advances in diagnostic methods and therapeutic approaches in the near future.
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PMID:[Dementia with Lewy bodies]. 1121 12

The human arcuate nucleus (ArcN) has been considered akin to the pontine precerebellar nuclei. However, there is anatomical, functional, and clinical evidence that the ArcN may be the homologue of chemosensitive areas of the ventral medullary surface involved in ventilatory responses to hypercarbia and cerebrospinal fluid acidosis. Acetylcholine has been involved in mechanisms of central chemosensitivity. Loss of ArcN neurons has been reported in patients with multiple system atrophy (MSA), a disorder characterized by disturbed automatic ventilation, but the neurochemical identity of these neurons is undetermined. We sought to determine whether the ArcN contains cholinergic neurons and whether these neurons are depleted in patients with MSA. Medullae were obtained from six patients with MSA, five patients with Parkinson's disease (PD) and six sex- and age-matched controls. Fifty-micron transverse sections obtained through the mid-olivary levels were processed for acetylcholinesterase (AchE), choline acetyltransferase (CAT), and alpha-synuclein immunoreactivity. We found that the ArcN contained CAT-positive neurons. There was a significant decrease in density of cholinergic ArcN neurons in MSA but not in PD patients. alpha-Synuclein-containing inclusions were present in the ArcN of MSA patients. Depletion of cholinergic neurons may provide a substrate for disturbances in automatic respiration in MSA patients.
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PMID:Depletion of cholinergic neurons of the medullary arcuate nucleus in multiple system atrophy. 1147 92

Advanced Parkinson's disease (PD) is frequently associated with dementia. The pathogenesis of this dementia is complex, related to deficiency of several biogenic amines and cortical Lewy body deposition, as well as co-existent age-related brain changes, both of the Alzheimer's type and vascular. However, degeneration of the cholinergic neurons in the nucleus basalis of Meynert may have an important contribution to the cognitive decline. The dementia of PD has a grave effect on the quality of life of the patients and their caregivers, as well as negative effect on their survival. The treatment of dementia associated with PD therefore must encompass several agents. We have treated several patients with the cholinesterase inhibitor rivastigmine which produced gratifying results. Future studies should define the exact role of this agent in the treatment of the dementia of PD.
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PMID:Dementia in Parkinson's disease. 1169 82

Patients suffering from Parkinson's disease (PD), often develop dementia (PDD). Their brain histology reveals Alzheimer's disease (AD) like changes and decreased cholin-acetyl transferase (ChAT) activity, in addition to typical PD changes. This cholinergic deficiency has been related to the degree of mental decline. As centrally acting cholinesterase inhibitors (ChEIs) provide cognitive and non-cognitive improvement for AD patients, the same therapeutic effect was hypothesized for PDD patients as well. The goal of this study was to assess the effect of ChEIs on both the cognitive and motor state of PDD patients. An open study was conducted. Eleven consecutive PDD patients (M/F 6/5 mean age 75 y) were found eligible for inclusion. They were treated for 26 weeks with tacrine (7 patients) and donepezil (4 patients) as add-on to their regular anti PD drugs. Cognitive assessment was performed at baseline and endpoint by Mini-Mental-State-Examination (MMSE) and Alzheimer's-Disease-Assessment-Scale (ADAS-cog). Global Deterioration Scale (GDS) was performed to evaluate active daily living (ADL). Motor evaluation was performed using Short Parkinson Evaluation Scale (SPES) at baseline and end-point. Statistical analysis used Student's paired t-test, ANOVA with repeated measures and Pearson correlation coefficient. ChEIs treated PDD patients showed improvement in their cognitive state. Mean ADAS-cog improved significantly by 3.2 points (p < 0.012). Mean MMSE and GDS improved non-significantly by 1.2 and 0.2 points respectively. There was no change in motor function as evident by mean SPES scores, 16.5 at baseline and endpoint. Five individuals actually demonstrated motor improvement under ChEIs. We conclude that ChEIs have a beneficial effect on the cognitive state of PDD patients without aggravating motor function.
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PMID:The beneficial effect of cholinesterase inhibitors on patients suffering from Parkinson's disease and dementia. 1176 30


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