L-Glutamate, L-arginine and L-citrulline levels in cerebrospinal fluid of Parkinson's disease, multiple system atrophy, and Alzheimer's disease patients

Summary. Alterations in neuronal nitric oxide (NO) production may play a role in the pathophysiology of Parkinson's disease (PD) Alzheimer's disease (AD), and multiple system atrophy (MSA). The biosynthesis of NO is dependent on the availability of L-arginine, the substrate for NO-synthase (NOS), and on L-glutamate, which stimulates NO synthesis via the NMDA receptor. In this process L-citrulline is formed. We measured the levels of these amino acids in cerebrospinal fluid (CSF) of 108 PD patients, 12 AD patients, 15 MSA patients and 21 healthy subjects. A slight but statistically significant elevation of CSF L-citrulline was found in MSA patients, while CSF L-glutamate was found to be significantly decreased in AD patients. We found no significant changes in L-arginine levels. Although the relation between the CSF levels of these amino acids and neuronal NO production is still unclear, our findings suggest that AD is associated with a decrease in NO synthesis. Received November 2, 1998; accepted October 26, 1999     

Cerebrospinal fluid ferritin levels of patients with Parkinson's disease, Alzheimer's disease, and multiple system atrophy

Summary Iron is believed to play a role in the pathogenesis of both Parkinson's disease (PD) and Alzheimer's disease (AD). We measured ferritin, which is considered to be the iron storage protein, in CSF of patients with PD, AD, and multiple system atrophy (MSA) as well as control subjects. We found a significant increase in CSF ferritin in AD compared with both PD and age-matched controls. No significant differences were found between PD patients with dementia (PDD) and non-demented PD patients. For non-demented PD patients a positive correlation between CSF ferritin and age was found. Our results may indicate that iron has a role in the pathophysiology of AD.     

Cerebrospinal fluid analysis differentiates multiple system atrophy from Parkinson's disease.

We investigated whether cerebrospinal fluid (CSF) analysis discriminates between idiopathic Parkinson's disease (PD; n = 35) and multiple system atrophy (MSA; n = 30). The median CSF concentration of the neurotransmitter metabolites 5-hydroxyindolacetic acid (5-HIAA) and 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG) was reduced significantly (49-70%) in MSA compared to PD. In contrast, several brain-specific proteins (tau, neuron-specific enolase, myelin basic protein) were elevated (130-230%) in MSA compared with those in PD. A combination of CSF tau and MHPG discriminated PD from MSA (adjusted odds ratios: tau, 27.2; MHPG, 0.14). Our data suggest that the more progressive and widespread neurodegenerative nature of MSA, as compared with PD, is reflected in the composition of CSF. We propose that CSF analysis may become part of the diagnostic work-up of patients with parkinsonian syndromes.     

Cerebrospinal fluid proteomic patterns discriminate Parkinson's disease and multiple system atrophy

The differential diagnosis of Parkinson's disease and multiple system atrophy can be challenging, especially in the early stages of the diseases. We developed a proteomic profiling strategy for parkinsonian diseases using mass spectrometry analysis for magnetic-bead-based enrichment of cerebrospinal fluid peptides/proteins and subsequent multivariate statistical analysis. Cerebrospinal fluid was obtained from 37 patients diagnosed with Parkinson's disease, 32 patients diagnosed with multiple system atrophy, and 26 patients diagnosed with other neurological diseases as controls. The samples were from the first cohort and the second cohort. Cerebrospinal fluid peptides/proteins were purified with C8 magnetic beads, and spectra were obtained by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Principal component analysis and support vector machine methods are used to reduce dimension of the data and select features to classify diseases. Cerebrospinal fluid proteomic profiles of Parkinson's disease, multiple system atrophy, and control were differentiated from each other by principal component analysis. By building a support vector machine classifier, 3 groups were classified effectively with good cross-validation accuracy. The model accuracy was well preserved for both cases, training by the first cohort and validated by the second cohort and vice versa. Receiver operating characteristics proved that the peak of m/z 6250 was the most important to differentiate multiple system atrophy from Parkinson's disease, especially in the early stages of the disease. A proteomic pattern classification method can increase the accuracy of clinical diagnosis of Parkinson's disease and multiple system atrophy, especially in the early stages.     

Anorectal function in multiple system atrophy and Parkinson's disease.

This study was designed to investigate anorectal function in Parkinson's disease and multiple system atrophy (MSA). After a standardized interview, 17 patients with Parkinson's disease (PD) and 16 patients with multiple system atrophy (MSA) underwent anorectal manometry with a continuously perfused multi-lumen catheter, located to record pressures from the anal canal, and a balloon for rectal distension. Data were analyzed by observers blind to the neurologic diagnosis. Disease duration was shorter in the MSA than in the PD group (6+/-4 versus 10+/-5 yrs, p<0.05). Most patients reported a bowel frequency of less than three evacuations per week and some patients had fecal incontinence. Most manometric recordings disclosed an abnormal pattern during straining (a paradoxic contraction or lack of inhibition) in 13 patients with MSA and 11 patients with PD. Mean anal pressures and rectal sensitivity threshold were not significantly higher in the MSA group, whereas the inhibitory anal reflex and rectal compliance thresholds were within the normal range in both groups. Manometric patterns did not differentiate patients with MSA from patients with PD. Most patients in both groups showed an abnormal straining pattern, decreased anal tone, or both dysfunctions. In conclusion, our findings suggest that although bowel and anorectal dysfunctions do not differentiate MSA from PD, both abnormalities occur earlier and develop faster in MSA than in PD.     

Brain-derived neurotrophic factor gene polymorphisms in Japanese patients with sporadic Alzheimer's disease, Parkinson's disease, and multiple system atrophy.

We studied two genetic polymorphisms (240C/T and 480G/A) of the brain-derived neurotrophic factor (BDNF) gene in Japanese patients with Alzheimer's disease (AD, n = 172), Parkinson's disease (PD, n = 327), and multiple system atrophy (MSA, n = 122), as well as controls (n = 275). The distribution of the 240 C/T polymorphism was significantly different between AD patients and controls, whereas there was no difference in the genotype of the two polymorphisms between MSA and controls or between PD and controls. Our data suggest that BDNF might play a role in AD.     

beta-Endorphin-like immunoreactivity in cerebrospinal fluid of patients with Alzheimer's disease and Parkinson's disease

beta-Endorphin-like immunoreactivity (beta-EP-LI) in cerebrospinal fluid (CSF) was measured in 42 patients with Alzheimer's disease (AD), 36 patients with Parkinson's disease (PD), and 35 controls. Values for patients with Alzheimer's disease (10.9 +/- 2.8 pmol/l) seemed to be lower than those for controls (12.9 +/- 2.5 pmol/l) (P less than 0.05). In addition, the severely demented patients had lower values than the moderately demented (P less than 0.01). In patients with Parkinson's disease no significant difference in beta-EP-LI values was observed compared to the controls. The data suggest, that processing of pro-opiomelanocortin, precursor of beta-endorphin, and the mechanism of cognitive impairment may differ in Alzheimer's disease and Parkinson's disease.     

Cardiovascular dysautonomia in Parkinson's disease and multiple system atrophy

OBJECTIVES: To determine whether Parkinson's disease (PD) can be distinguished from multiple system atrophy (MSA) on the basis of the assessment of iodine-123 meta-iodobenzylguanidine (123I-MIBG) radioactivity in heart and cardiovascular autonomic function. PATIENTS AND METHODS: Seventeen patients with MSA, 39 with PD, and 25 healthy volunteers underwent 123I-MIBG scintigraphy and hemodynamic autonomic function tests using Valsalva maneuver (VM). Baroreceptor reflex sensitivity (BRS) was measured using the slope of the relation between RR interval and blood pressure during the fourth phase. RESULTS: 123I-MIBG radioactivity in heart of patients with PD was lower than that of control subjects and patients with MSA, but there was some overlap between PD and MSA. BRS in patients with PD who had a 123I-MIBG radioactivity similar to that in MSA was larger than that in patients with MSA, with no overlap in any patient. CONCLUSION: Assessment of BRS may be useful for differentiating between MSA and PD that had a 123I-MIBG radioactivity similar to MSA.     

Urodynamic and neurophysiological evaluation in Parkinson's disease and multiple system atrophy.

AIMS: To determine whether Parkinson's disease and multiple system atrophy each has a distinct pattern of micturition abnormalities and whether a urodynamic evaluation could be useful in the differential diagnosis between the two diseases. METHODS: Sixty two patients (30 with Parkinson's disease and 32 with multiple system atrophy) underwent a complete urodynamic evaluation and neurophysiological testing. RESULTS: Of the parkinsonian patients 36.6% had normal micturition findings with normal bladder sensitivity; 26.7% had delayed or incomplete pelvic floor relaxation; 26.7% had hyperreflexia with vesicosphincteric synergy; and 10% had hyperreflexia with vesicosphincteric synergy associated with incomplete pelvic floor relaxation. Parkinsonian patients with a normal urodynamic pattern had significantly less severe disease and a shorter duration of disease in years than those who had abnormal patterns. Patients with hyperreflexia had significantly higher severity of disease. All the patients with multiple system atrophy had hyperreflexia with synergy. Two urodynamic patterns were identified: hyperreflexia with vesicosphincteric synergy (90.6% of patients), and hyperreflexia with vesicosphincteric synergy and incomplete pelvic floor relaxation (in 9.4%). Hyperreflexia with synergy correlated neither with the severity nor with the duration of disease. Sphincter EMG analysis showed that all the parkinsonian patients had normal sphincter EMG whereas 24 of the 32 patients with multiple system atrophy had neurogenic signs. CONCLUSIONS: Urodynamic evaluation and sphincter EMG are both useful tests in the differential diagnosis between Parkinson's disease and multiple system atrophy. Urodynamic findings may be abnormal before patients with multiple system atrophy reach an advanced stage of the disease. Recordings of EMGs from perineal muscles become abnormal as the disease progresses in multiple system atrophy but not in Parkinson's disease.     

Normal cerebrospinal fluid levels of insulin in patients with Parkinson's disease

Summary. We compared CSF levels insulin, measured by a Radioimmunoanalysis method, in 24 patients with Parkinson's disease (PD) and 21 matched controls. The CSF insulin levels did not differ significantly between PD patients and controls. CSF insulin levels were not correlated with age, age at onset, duration of the disease, scores of the Unified Parkinson Disease Rating Scale of the Hoehn and Yahr staging in the PD group. Antiparkinsonian therapy did not influence significantly and CSF levels of insulin. These results suggest that CSF insulin concentrations are not a biological marker of PD and its severity. Received July 14, 1999; accepted September 16, 1999     

Phosphorus magnetic resonance spectroscopy in multiple system atrophy and Parkinson's disease.

We performed in vivo phosphorus magnetic resonance spectroscopy on the occipital lobes of 15 patients with multiple system atrophy (MSA; eight with olivopontocerebellar atrophy [OPCA] and seven with the striatonigral degeneration variant [SND]), 13 patients with idiopathic Parkinson's disease (PD), and 16 age-matched healthy subjects. The MSA group showed significantly reduced phosphocreatine (PCr), increased inorganic phosphate (Pi), and unchanged cytosolic free [Mg2+], and pH. We did not find any significant difference between the OPCA and SND variants. However, patients with PD showed significantly increased content of Pi, decreased cytosolic free [Mg2+], and unchanged [PCr] and pH. Comparing the MSA and PD groups, [PCr] was significantly lower in MSA than in PD, whereas cytosolic free [Mg2+] was significantly lower in PD. Despite a certain degree of overlap of [PCr] and [Mg2+] values between the two groups, by considering both variables at the same time it was possible to classify correctly 93% of cases by discriminant analysis. We conclude that phosphorus magnetic resonance spectroscopy discloses abnormal phosphate metabolite and ion contents in both MSA and PD, respectively, and may provide noninvasive diagnostic help to differentiate MSA from PD.     

Executive function differences in multiple system atrophy and Parkinson's disease

The aim of the present study was to assess executive function in patients with multiple system atrophy (MSA) and Parkinson's disease (PD) looking for specific differences and considering motor disability and disease duration. Performance of 11 MSA patients was compared to that of 12 healthy controls and two groups of 12 PD patients, one matched with respect to the severity of motor symptoms and the other with respect to disease duration. Compared to healthy controls, MSA and PD patients both presented executive dysfunction but, in MSA, the impairment was more severe and diffuse. This study suggests that despite the evidence of some differences in executive function in MSA and PD, the contribution of standard neuropsychological examination to the differential diagnosis of both syndromes remains still limited.