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)

Animal studies have suggested an increased striatal glutamate activity in Parkinson's disease models, although this has not been substantiated in magnetic resonance spectroscopy studies in patients. Our initial aim was to assess glutamate and glutamine levels in the striatum of patients with idiopathic Parkinson's disease, using multivoxel proton magnetic resonance spectroscopy techniques. Since data were collected from other areas of the brain without a priori selection, information on the cortex was also obtained. Twelve healthy volunteers, seven dyskinetic and five non-dyskinetic patients were studied. Peak area ratios of choline-containing compounds (Cho), glutamine and glutamate (Glx) and N-acetyl moieties including N-acetylaspartate (NAx), relative to creatine (Cr) were calculated. Spectra were analysed from the corpus striatum, the occipital cortex and the temporo-parietal cortex. The median Glx/Cr ratio was unaltered in the striatal spectra of Parkinson's disease patients compared to healthy controls. However, the more severely affected patients had significantly reduced NAx/Cr ratios in spectra localised to the temporo-parietal cortex, compared to healthy controls. Furthermore, the entire patient population had significantly reduced Cho/Cr ratios in spectra from the temporo-parietal cortex, compared to the reference population. We found no evidence of increased striatal glutamate in either dyskinetic or non-dyskinetic Parkinson's disease. However, the low NAx/Cr and Cho/Cr ratios in the temporo-parietal cortex may indicate the presence of subclinical cortical dysfunction.
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PMID:A proton magnetic resonance spectroscopy study of the striatum and cerebral cortex in Parkinson's disease. 1034 13

To better define the survival and cellular composition of human fetal neurotransplants in vivo, we performed quantitative 1H MRS to determine the concentration of the neuronal amino acid [N-acetylaspartate] within MRI-visible grafts. In all, 71 grafts in 38 patients [24 Parkinson's disease (PD), 14 Huntington's disease (HD)] were examined, as well as 24 untreated PD and HD patients and 13 age-matched normal controls. MRI appearances of edema were present in three out of 71 grafts, the remainder being consistent with histologically identified viable neural transplant tissue. N-acetylaspartate (NAA), creatine, choline, myoinositol and glutamine plus glutamate (Glx) were identified in all post-transplant putamens, with abnormal metabolites, lactate and/or lipid detectable in only three patients. Of 71 grafts, 19 occupied more than 60% of the MRS-examined volume (VOI) (mean 84.2 +/- 3%; range 61-100%). In those, [NAA] was 8.50 +/- 0.99 mM in eight PD spectra and 6.59 +/- 0.81 mM in 11 HD spectra, and was not significantly different from controls. In contrast, transplanted fetal neurones contain less than 0.4 mM of the neuronal amino acid NAA. This suggests that established fetal neurotransplants in the human putamen of both PD and HD patients are populated by adult neurones, axons and dendrites.
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PMID:In vivo magnetic resonance spectroscopy of human fetal neural transplants. 1042 14

Proton magnetic resonance spectroscopy ((1)H-MRS) was performed in patients with a clinical diagnosis of idiopathic Parkinson's disease (IPD), multiple system atrophy (MSA) or progressive supranuclear palsy (PSP) in order to assess metabolic differences between the three groups of patients. Single-volume (1)H-MRS, localized to the lentiform nucleus, was carried out in 19 IPD patients, 14 MSA patients, 11 PSP patients and 12 age-matched healthy subjects. The signals of N-acetylaspartate (NAA), choline-containing compounds (Cho) and creatine-phosphocreatine (Cr) were evaluated as peak area ratios. The NAA/Cho peak ratio was significantly reduced in MSA and in PSP patients compared to IPD patients and to controls. The NAA/Cr peak ratio was significantly reduced in MSA, in PSP and in IPD patients compared to controls, but only in MSA compared to IPD patients. The NAA reduction in the basal ganglia of MSA and PSP patients may reflect a neuronal loss or damage. Single-volume (1)H-MRS may be a useful tool in differentiating MSA and PSP from IPD patients.
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PMID:Usefulness of proton magnetic resonance spectroscopy in differentiating parkinsonian syndromes. 1055 8

Six patients with idiopathic Parkinson's disease (IPD), six with clinically probable multiple system atrophy and six control subjects underwent quantitative proton magnetic resonance spectroscopy (MRS). The concentrations of the three major metabolites, N-acetylaspartate (NAA), creatine and choline, were quantified in the lentiform nucleus using tissue water content as an internal concentration reference. Glutamate was assessed as the (glutamate + glutamine)/creatine peak area ratio (Glx/Cre). In the control subjects the mean (+/- SD) concentrations of the three metabolites were 15.2 +/- 2.9 micromol/g wet weight for NAA, 12.0 +/- 1.4 for creatine and 2.4 +/- 0.3 for choline. The Glx/Cre ratio was 1.28 +/- 0.32. The only significant difference in any metabolite concentration was in the lentiform nucleus of patients with IPD compared with controls, with an increase in choline which lead to a significant reduction in the NAA/choline ratio. The relevance of this finding is uncertain. The results of the present pilot study, combined with the conflicting findings from previous work, suggest that further, much larger, studies are required to evaluate the diagnostic capability of proton MRS.
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PMID:Basal ganglia metabolite concentrations in idiopathic Parkinson's disease and multiple system atrophy measured by proton magnetic resonance spectroscopy. 1113 52

Proton MR spectroscopy (1H-MRS) has been previously performed in Parkinson's disease (PD) and parkinsonian syndromes to evaluate in vivo concentrations of basal ganglia and cerebral cortex metabolites such as N-acetylaspartate (NAA), choline (Cho), and creatine (Cr). However, this technique has never been used to evaluate motor cortex in untreated PD patients. In this study, single-voxel 1H-MRS of basal ganglia and motor cortex was carried out in 10 de novo patients with PD and 10 age-matched healthy controls. A significant reduction in the NAA/Cr ratio was observed in the motor cortex of PD patients compared with controls (p)<(0.01). Basal ganglia spectra did not allow any evaluation due to the presence of artefacts related to inorganic paramagnetic substances. The motor cortex reduction of the NAA/Cr ratio in de novo PD patients may reflect an altered neuronal functioning due to a loss of thalamocortical excitatory inputs and may represent an in vivo marker for the diagnosis of PD.
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PMID:Proton magnetic resonance spectroscopy (1H-MRS) of motor cortex and basal ganglia in de novo Parkinson's disease patients. 1148 6

It has been suggested that proton magnetic resonance spectroscopy (MRS) of the striatum can differentiate between parkinsonian syndromes. The present study aims to examine this claim by performing a systematic review of the existing literature. A MEDLINE search was performed between 1966 and October 1999, along with searches of conference abstracts and reference lists of papers identified. Eleven groups have used MRS to examine metabolite ratios in the striatum in Parkinsonian syndromes. A number of these have shown reduced N-acetylaspartate/choline (NAA/Cho) and/or N-acetylaspartate/creatine (NAA/Cr) ratios in either idiopathic Parkinson's disease (IPD), multiple system atrophy (MSA), progressive supranuclear palsy (PSP) or corticobasal degeneration. However, the heterogeneity in the results precludes the use of any of these findings in differential diagnosis at the present time. The only group to use absolute metabolite concentrations rather than ratios showed that the decreased NAA/Cho ratio in IPD was because of an increase in choline which is of uncertain biological significance. Further large multicentre trials are required using absolute quantitation of tissue metabolite concentrations and a standardized technique. The patients entering such studies must be rigorously assessed to establish the diagnosis of the type of parkinsonism as accurately as possible. Any discriminatory abnormality must be tested in a large prospective study of newly presenting parkinsonian patients with long-term clinical follow up and ultimate pathological confirmation of the diagnosis as far as possible.
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PMID:Systematic review of proton magnetic resonance spectroscopy of the striatum in parkinsonian syndromes. 1178 41

Proton magnetic resonance spectroscopy ((1)H-MRS) provides a non-invasive, in vivo insight into the brain metabolism, and has been successfully used in several neurological conditions. Our objective was to characterise the cerebral metabolic changes in dementia with Lewy bodies (DLB) patients using (1)H-MRS. Single Voxel (1)H-MRS was performed in 12 DLB patients with mild to moderate symptoms and 11 age-matched healthy controls. Volumes of interest (VOI) were selected, including white matter (WM) in the centrum semiovale and grey matter (GM) in the parasagittal parietal cortex. Main metabolic peaks corresponding to N-acetylaspartate (NAA), glutamate/glutamine (Glx), choline-containing compounds (Cho), myo-inositol (Ins), and creatine plus phosphocreatine (Cr) were identified. These areas were measured and referred to that of the water. Metabolic ratios among the different peak areas were also calculated. In comparison with the control group, DLB patients showed significantly lower mean NAA/Cr, Glx1/Cr and Cho/Cr ratios in the WM, while their Ins/Cr and Ins/NAA ratios did not differ from those of the control group. In the GM, no significant differences were found between both groups. Correlations between age at onset, disease duration, Mini-Mental State Examination, the motor section of the Unified Parkinson's Disease Rating Scale, Hoehn and Yahr staging and metabolic ratios, both for WM and GM, were not significant in DLB patients. Our spectroscopy data show WM involvement, along with GM preservation, in DLB patients with early or intermediate stages. Hence, (1)H-MRS may provide adjunctive information in the ante-mortem diagnosis of DLB.
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PMID:Proton magnetic resonance spectroscopy in dementia with Lewy bodies. 1237 33

We administered 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) to adult, male cats to model Parkinson's disease (PD), and utilized proton magnetic resonance imaging (MRI) and spectroscopy (MRS) at a field strength of 1.5 T to identify metabolic degenerative changes in the striatum in vivo. Neurologic status and somatosensory-evoked potentials in vivo, as well as postmortem striatal histopathological and immunohistochemical parameters, were examined. Nine cats were equally divided into three groups and treated daily for 10 days as follows: saline, MPTP, and pargyline (a monoamine oxidase inhibitor) plus MPTP. The MPTP-treated cats displayed bradykinesia, head tremor, and reduced oculovestibular reflex activity. MRI showed a diffuse increase of the T2-weighted signal in the striatum of two MPTP-treated cats. Analysis of the MRS spectra indicated significantly lower N-acetylaspartate/creatine (CR) and glutamine-glutamate complex/CR ratios than the control baseline. Two MPTP-treated cats had low choline-containing compounds/CR ratio, whereas a lactate peak was present in all MPTP-treated cats. In the striatum of the MPTP-treated cats, there was a significant decline of tyrosine hydroxylase immunoreactivity and histological evidence for a diffuse cytotoxic reaction. Pretreatment with pargyline attenuated the MPTP-induced clinical signs, MRI and MRS changes, and the histopathological and immunoreactivity alterations. We conclude that proton MRI/MRS is a sensitive, noninvasive measure of neural toxicity and biochemical alteration of the striatum in a feline model of PD.
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PMID:Proton magnetic resonance imaging and spectroscopy identify metabolic changes in the striatum in the MPTP feline model of parkinsonism. 1261 22

To investigate whether there are significant changes in regional brain metabolism in patients with Parkinson's disease before and after thalamotomy using proton magnetic resonance spectroscopy (1H MRS). Fifteen patients underwent 15 stereotactic thalamotomies for control of medically refractory parkinsonian tremor. Single-voxel 1H MRS was carried out on a 1.5 T unit using stimulated-echo acquisition mode (STEAM) sequence (TR/TM/TE, 2000/14/20 ms). Spectra were obtained from substantia nigra, thalamus and putamen areas with volumes of interests (7-8 ml) in patients before and after the surgery. Metabolite ratios of NAA/Cho, NAA/Cr and Cho/Cr were calculated from relative peak area measurements. We evaluated alterations of metabolite ratios in brain metabolism in Parkinson's disease patients with clinical outcome following thalamotomy. NAA/Cho ratios showed generally low levels in substantia nigra and thalamus in Parkinson's disease patients with clinical improvement following thalamotomy. In 80% (12/15) patients, decreased NAA/Cho ratios were observed from the selected voxels in substantia nigra after thalamic surgery (P<0.05). The ratios were also significantly decreased in thalamus in 67% (10/15) patients with clinical improvement (P<0.05). Our results suggest that NAA/Cho ratio may be a valuable criterion for evaluation of Parkinson's disease patients with the clinical improvement following surgery. 1H MRS may be a useful utility for the aid in better understanding the pathophysiologic process in Parkinson's disease patients on the basis of the variation of NAA/Cho ratio.
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PMID:Proton MR spectroscopic changes in Parkinson's diseases after thalamotomy. 1292 60

The anterior cingulate (AC) gyrus and the presupplementary motor area (pre-SMA) show pathological changes in Parkinson's disease (PD). We examined if PD patients show magnetic resonance spectroscopy (MRS) changes in NAA/Cr in the AC, pre-SMA, or posterior cingulate (PC). Forty-four (27 male, 17 female) healthy nondemented PD patients and 38 controls (18 male, 20 female) 65 years of age and older were examined using the Unified Parkinson's Disease Rating Scale (UPDRS), Mini-Mental State Examination, Frontal Assessment Battery, and Geriatric Depression Scale. MRS was performed at 1.5 T. Voxels (8 cc; PRESS; TE = 80; TR = 1,600 ms) were placed mid-sagittally. Gray matter and white matter volumes were measured within voxels using SPM2. Spectra were analyzed using LC model to yield NAA/Cr and Cho/Cr. Demographic and cognitive measures did not differ between groups. Motor UPDRS was 17.7 +/- 8.8 for PD. Pre-SMA NAA/Cr was lower in PD (PD: 1.39 +/- 0.17; control: 1.47 +/- 0.16; P = 0.045) and correlated negatively with age (r = 0.39; P = 0.01), but not with UPDRS, disease duration, or dopamine equivalents. AC and PC NAA/Cr and Cho/Cr in any region did not differ (P > 0.05). In conclusion, pre-SMA NAA/Cr was selectively decreased in PD, consistent with neuronal dysfunction. This should be further examined as a biomarker of disease in PD.
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PMID:Magnetic resonance spectroscopic evidence for presupplementary motor area neuronal dysfunction in Parkinson's disease. 1721 52


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