Showing papers by "Wilfried Kuhn published in 2009"

Interleukin-6 levels in cerebrospinal fluid inversely correlate to severity of Parkinson's disease.

Abstract: Introduction - Several lines of evidence suggest that neuroimmune mechanisms may also be involved in neurodegeneration in Parkinson's disease (PD). The potential role of cytokines such as interleukin 6 (IL-6), in the interaction between neurons and immune system has been emphasized by recent findings. IL-6 induces acute phase protein synthesis, differentiation of neuronal cells and improves catecholaminergic and cholinergic cell survival in the brain. Subjects and methods - We determined levels of IL-6 in cerebrospinal fluid (CSF) of untreated parkinsonian patients and age- and sex-matched controls. Intensity of disease was evaluated by the Unified Parkinson's Disease Rating scale. Results - Significantly elevated levels of IL-6 were found in the CSF of parkinsonian patients. Moreover a significant inverse correlation between severity of PD and IL-6 CSF levels appeared. Discussion - Elevated IL-6 levels in the CSF of untreated parkinsonian patients may reflect the original condition in the course of disease. We speculate that an endogenous upregulation of IL-6 synthesis occurs in order to regenerate lesioned neurons probably at an early phase of the degenerative process in PD.

Homocysteine levels after acute levodopa intake in patients with Parkinson's disease.

Abstract: Levodopa (L-dopa) administered with a dopadecarboxylase inhibitor (DDI) increases homocysteine plasma levels. This may support the onset of atherosclerosis-related disorders and neuropsychiatric complications in patients with Parkinson's disease (PD). This homocysteine elevation is considered as long-term effect of chronic L-dopa/DDI treatment. Little is known about the acute effects of L-dopa/DDI intake on homocysteine generation. The objective of this trial was to investigate the relations between L-dopa and homocysteine after acute L-dopa/DDI administration in PD patients with different L-dopa metabolism. Thirty PD patients were divided into groups with superior (I) and less (II) L-dopa absorption after standardized intake of 125 mg L-dopa/benserazide with determination of L-dopa, 3-O-methyl-dopa (3-OMD) and homocysteine in plasma at baseline, 30, 60, and 90 minutes. There was a homocysteine increase in Group I (F = 5; P = 0.005) and a moderate decrease in Group II (F = 4.27; P = 0.01). A rise of 3-OMD (F = 10.51; P < 0.0001) appeared in Group I, but not in Group II (F = 0.91; P = 0.44), accordingly L-dopa accumulation was better in Group I than in Group II. Thus, in conclusion, L-dopa metabolism is an important component for homocysteine elevation after one time L-dopa/DDI administration in PD patients. © 2009 Movement Disorder Society

Plasma levels of the β‐carbolines harman and norharman in Parkinson's disease

Abstract: Several lines of evidence suggest that endogenous and exogenous toxins may play a major role in the pathogenesis of Parkinson's disease (PD). In vivo aromatic beta-carbolines, like harman or norharman, may easily be formed by cyclization of indoleamines with e.g. aldehydes. Because of the structural similarity to MPTP, beta-carbolines have been proposed as endogenous toxins. For further elucidation of the role of beta-carbolines in neurodegenerative disorders, harman and norharman plasma levels were measured in 36 patients with PD and compared to an age- and sex-matched control group. Plasma levels of norharman in PD were significantly higher compared to the control group. Harman in the plasma of Parkinsonian patients was also elevated compared to controls, but this difference was not significant. Correlation of beta-carbolines with plasma levels of L-dopa, oral doses of bromocriptine and selegiline in treated Parkinsonian patients showed no significant results. On the one hand these results may suggest a possible role of beta-carbolines in the pathophysiological processes initiating PD, by, e.g., inducing mitochondrial respiratory inhibition like MPP+. One may speculate, however, that elevated levels of norharman and harman are due to an endogenous upregulation caused by unknown metabolic processes.

Cysteine elevation in levodopa-treated patients with Parkinson's disease.

Abstract: Homocysteine, cysteine, and cysteinyl-glycine are all metabolically interrelated. Levodopa/decarboxylase inhibitor (LD/DCI) administration increases total homocysteine (tHcy) plasma levels. Objectives were to investigate associations between LD/DCI intake, concentrations of tHcy, cysteine, and cysteinyl-glycine in PD patients and healthy controls. Cysteine levels were significant lower in controls and PD patients with tHcy below the treshold of 15 [μmol/L] when compared with PD patients with tHcy above 15. Cysteinyl-glycine did not significantly differ between the three cohorts. Significant associations appeared between tHcys and cysteine in PD patients. tHcy and cysteine concentrations correlated to LD/DCI intake and severity of PD. The cysteine increase may be due to the significant higher dosing of daily LD/DCI and the significant higher morning LD/DCI dose 1 hour before blood sampling in PD patients with tHcy above 15 when compared with the remaining PD patients and the controls. The correlation outcomes support the view that LD/DCI intake may also increase cysteine. © 2009 Movement Disorder Society

Palinopsia as sensory epileptic phenomenon.

Abstract: Visual perseveration (VP) is defined as persistence or recurrence of visual images, when the stimulus is no longer present. We report three patients with occipital cortical lesions in the right hemisphere and VP. Electroencephalography showed epileptic abnormalities in all cases. In one patient synchronous electroencephalic recordings during the onset of palinopsia - a subtype of VP - revealed, that VP was associated with a clear cut right occipital seizure with a secondary diffusion of the discharge over both hemispheres, which has not been reported in combination with the onset of palinopsia heretofore. In all three patients sensory seizures have to be considered as probable cause of VP.

Distorted colour discrimination in Parkinson's disease is related to severity of the disease.

Abstract: The Farnsworth-Munsell 100-hue test (FMT) may be used for measurement of colour discrimination and error scores of the FMT provide an unspecific biological marker for the distinction between parkinsonian patients (PP) and healthy controls. The aim of this study was to examine the possible association between distorted colour discrimination and disease severity in untreated de novo PP. Error scores of the FMT were significantly (P<0.0001) elevated in PP compared to age- and sex-matched controls and correlated to severity of the disease. We conclude that impaired colour discrimination is related to pathophysiology of Parkinson's disease. But it remains unclear whether these alterations of colour vision reflect striatal dopamine deficiency or changes of retinal dopaminergic pathways in PP.

Delayed motor response correlates with striatal degeneration in Parkinson's disease

Abstract: Objective Studies on reaction time have suggested a selective deficit of slowness in motor readiness and motor programming in Parkinson's disease (PD). Objective of this study was the putative relation between delayed initiation and execution of movement and the striatal dopamine deficiency in PD. Material and methods We investigated 32 idiopathic, previously untreated parkinsonian patients to evaluate dopaminergic nigrostriatal degeneration by single photon emission tomography in combination with the radiotracer [123I]-beta-CIT and performed a simple reaction time paradigm on the same day. Results Significant relations between the [123I]-beta-CIT-SPECT-ratio striatum/cerebellum and reaction--and movement time appeared. Reaction time and movement time of parkinsonian patients were significantly longer compared to age-matched controls. Conclusions We conclude that reaction- and movement-time is related to the dopaminergic nigrostriatal degeneration in untreated parkinsonian subjects.