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Parkinson&rsquo, s disease Multimodal Complex Treatment (PD-MCT) is a multidisciplinary inpatient treatment approach that has been demonstrated to improve motor function and quality of life in patients with Parkinson&rsquo, s disease (PD). In this study, we assessed the efficacy of PD-MCT and calculated predictors for improvement. We performed a prospective analysis in a non-randomized, open-label observational patient cohort. Study examinations were done at baseline (BL), at discharge after two-weeks of inpatient treatment (DC) and at a six-week follow-up examination (FU). Besides Movement Disorders Society Unified Parkinson&rsquo, s Disease Rating Scale (MDS-UPDRS) III as a primary outcome, motor performance was measured by the Timed Up-and-Go (TUG), the Berg Balance Scale (BBS) and the Perdue Pegboard Test (PPT). Until DC, motor performance improved significantly in several parameters and was largely maintained until FU (MDS-UPDRS III BL-to-DC: &minus, 4.7 &plusmn, 1.2 (SE) p = 0.0012, BL-to-FU: &minus, 6.1 &plusmn, 1.3 p = 0.0001, TUG BL-to-DC: &minus, 2.5 &plusmn, 0.9 p = 0.015, BL-to-FU: 2.4 &plusmn, 0.9 p = 0.027, BBS BL-to-DC: 2.4 &plusmn, 0.7 p = 0.003, BL-to-FU: 1.3 &plusmn, 0.7 p = 0.176, PPT BL-to-DC: 3.0 &plusmn, 0.5 p = 0.000004, BL-to-FU: 1.7 &plusmn, 0.7 p = 0.059). Overall, nontremor items were more therapy responsive than tremor items. Motor complications evaluated with MDS-UPDRS IV occurred significantly less frequent at DC (&minus, 1.8 &plusmn, 0.5 p = 0.002). Predictor analyses revealed an influence of initial motor impairment and disease severity on the treatment response in different motor aspects. In summary, we demonstrate a significant positive treatment effect of PD-MCT on motor function of PD patients which can be maintained in several parameters for an extended time period of six weeks and identify predictors for an improvement of motor function.

Objective Magnetic resonance spectroscopy (MRS) is a non-invasive method to quantify neurometabolite concentrations in the brain. Within the framework of the WELDOX II study, we investigated the association of exposure to manganese (Mn) and iron (Fe) with γ-aminobutyric acid (GABA) and other neurometabolites in the striatum and thalamus of 154 men. Material and methods GABA-edited and short echo-time MRS at 3T was used to assess brain levels of GABA, glutamate, total creatine (tCr) and other neurometabolites. Volumes of interest (VOIs) were placed into the striatum and thalamus of both hemispheres of 47 active welders, 20 former welders, 36 men with Parkinson’s disease (PD), 12 men with hemochromatosis (HC), and 39 male controls. Linear mixed models were used to estimate the influence of Mn and Fe exposure on neurometabolites while simultaneously adjusting for cerebrospinal fluid (CSF) content, age and other factors. Exposure to Mn and Fe was assessed by study group, blood concentrations, relaxation rates R1 and R2* in the globus pallidus (GP), and airborne exposure (active welders only). Results The median shift exposure to respirable Mn and Fe in active welders was 23 μg/m3 and 110 μg/m3, respectively. Airborne exposure was not associated with any other neurometabolite concentration. Mn in blood and serum ferritin were highest in active and former welders. GABA concentrations were not associated with any measure of exposure to Mn or Fe. In comparison to controls, tCr in these VOIs was lower in welders and patients with PD or HC. Serum concentrations of ferritin and Fe were associated with N-acetylaspartate, but in opposed directions. Higher R1 values in the GP correlated with lower neurometabolite concentrations, in particular tCr (exp(β) = 0.87, p Conclusions Our results do not provide evidence that striatal and thalamic GABA differ between Mn-exposed workers, PD or HC patients, and controls. This may be due to the low exposure levels of the Mn-exposed workers and the challenges to detect small changes in GABA. Whereas Mn in blood was not associated with any neurometabolite content in these VOIs, a higher metal accumulation in the GP assessed with R1 correlated with generally lower neurometabolite concentrations.

Background and purpose The axial mesencephalic transcranial sonography plane is an established and sensitive diagnostic tool for the differentiation of Parkinson's disease and essential tremor. However, the substantia nigra can also be depicted in a second coronal examination plane, whose diagnostic value has not yet been evaluated. Furthermore, the M-mode tremor frequency determination represents another sonographic tool, which might yield additional diagnostic value. Methods We included patients with diagnosed Parkinson's disease (n = 31), essential tremor (n = 16), and healthy age-matched controls (n = 16). All were examined by transcranial sonography in the axial and coronal plane. Tremor frequencies were quantified by an M-mode tremor frequency determination examination protocol. A clinical assessment was conducted in all participants. Results The utilization of a coronal examination plane improved the diagnostic strength in discriminating of Parkinson's disease from essential tremor and healthy controls. In combination with the determination of tremor frequency, best discriminative results were achieved (sensitivity, 90.3%; specificity, 96.9%). In the Parkinson's disease group, we found a significant positive correlation between hyposmia and coronal hyperechogenicity. Conclusion The combined usage of coronal transcranial sonography and M-mode tremor frequency determination should be considered to improve diagnostic strength of sonographic techniques for the diagnosis of Parkinson's disease.

Parkinson’s disease (PD) is the world’s fastest growing neurological disorder disabling patients through a broad range of motor and non-motor symptoms. For the clinical management, a multidisciplinary approach has increasingly been shown to be beneficial. In Germany, inpatient Parkinson’s Disease Multimodal Complex Treatment (PD-MCT) is a well-established and frequent approach, although data on its effectiveness are rare. We conducted a prospective real-world observational study in 47 subjects [age (M ± SD): 68.5 ± 9.0 years, disease duration: 8.5 ± 5.3 years, modified Hoehn and Yahr stage (median, IQR): 3, 2.5–3] aiming at evaluating the effectiveness of 14-day PD-MCT in terms of quality of life (Parkinson’s Disease Questionnaire, EuroQol), motor [Movement Disorder Society Unified Parkinson’s Disease Rating Scale Part III (MDS-UPDRS III], Timed Up and Go Test, Purdue Pegboard Test) and non-motor symptoms (revised Beck Depression Inventory). Six weeks after hospital discharge, a follow-up examination was performed. PD patients with a predominantly moderate disability level benefited from PD-MCT in terms of health-related quality of life, motor symptoms and non-motor symptoms (depression). Significant improvements were found for social support, emotional well-being and bodily discomfort domains of health-related quality of life. Sustainable improvement occurred for motor symptoms and the subjective evaluation of health state. We found a higher probability of motor response especially for patients with moderate motor impairment (MDS-UPDRS III ≥ 33). In conclusion, Parkinson’s Disease Multimodal Complex Treatment improves motor symptoms, depression and quality of life. A more detailed selection of patients who will benefit best from this intervention should be examined in future studies.

Exposure to free radicals influences synthesis, degradation and function of proteins, such as repulsive guidance molecule A. Decay of this protein is essential for neuronal maintenance and recovery. Levodopa elevates oxidative stress. Therefore levodopa may impact repulsive guidance molecule A metabolism. Objectives were to investigate plasma concentrations of repulsive guidance molecule A, levodopa, cysteine and cysteinyl-glycine before and 1 h after levodopa application in patients with Parkinson's disease. Cysteine and cysteinyl-glycine as biomarkers for oxidative stress exposure decreased, repulsive guidance molecule A and levodopa rose. Repulsive guidance molecule A remained unchanged in levodopa naïve patients, but particularly went up in patients on a prior chronic levodopa regimen. Decay of cysteine specifically cysteinyl-glycine results from an elevated glutathione generation with rising cysteine consumption respectively from the alternative glutathione transformation to its oxidized form glutathione disulfide after free radical scavenging. Repulsive guidance molecule A rise may inhibit physiologic mechanisms for neuronal survival.

The etiology of Parkinson’s disease (PD) is significantly influenced by disease-causing changes in the protein alpha-Synuclein (aSyn). It can trigger and promote intracellular stress and thereby impair the function of dopaminergic neurons. However, these damage mechanisms do not only extend to neuronal cells, but also affect most glial cell populations, such as astroglia and microglia, but also T lymphocytes, which can no longer maintain the homeostatic CNS milieu because they produce neuroinflammatory responses to aSyn pathology. Through precise neuropathological examination, molecular characterization of biomaterials, and the use of PET technology, it has been clearly demonstrated that neuroinflammation is involved in human PD. In this review, we provide an in-depth overview of the pathomechanisms that aSyn elicits in models of disease and focus on the affected glial cell and lymphocyte populations and their interaction with pathogenic aSyn species. The interplay between aSyn and glial cells is analyzed both in the basic research setting and in the context of human neuropathology. Ultimately, a strong rationale builds up to therapeutically reduce the burden of pathological aSyn in the CNS. The current antibody-based approaches to lower the amount of aSyn and thereby alleviate neuroinflammatory responses is finally discussed as novel therapeutic strategies for PD.

The axial mesencephalic transcranial sonography plane is an established and sensitive diagnostic tool for the differentiation of Parkinson's disease and essential tremor. However, the substantia nigra can also be depicted in a second coronal examination plane, whose diagnostic value has not yet been evaluated. Furthermore, the M-mode tremor frequency determination represents another sonographic tool, which might yield additional diagnostic value.We included patients with diagnosed Parkinson's disease (n = 31), essential tremor (n = 16), and healthy age-matched controls (n = 16). All were examined by transcranial sonography in the axial and coronal plane. Tremor frequencies were quantified by an M-mode tremor frequency determination examination protocol. A clinical assessment was conducted in all participants.The utilization of a coronal examination plane improved the diagnostic strength in discriminating of Parkinson's disease from essential tremor and healthy controls. In combination with the determination of tremor frequency, best discriminative results were achieved (sensitivity, 90.3%; specificity, 96.9%). In the Parkinson's disease group, we found a significant positive correlation between hyposmia and coronal hyperechogenicity.The combined usage of coronal transcranial sonography and M-mode tremor frequency determination should be considered to improve diagnostic strength of sonographic techniques for the diagnosis of Parkinson's disease.

Introduction: Homocysteine increase and glutathione derivative cysteinyl-glycine fall are indirect biomarkers for oxidative stress, for instance due to dopamine D1 receptor stimulation.Objectives: To investigate the influence of the D1 receptor agonists levodopa and rotigotine compared with placebo on homocysteine and cysteinyl-glycine in plasma of patients with Parkinson’s disease.Methods: Patients received 100 mg levodopa, 4 mg rotigotine or placebo. Cysteinyl-glycine and homocysteine were measured every 30 min over three hours.Results: Homocysteine rose during levodopa- and placebo administration. Rotigotine had no effect. Cysteine-glycine only increased after placebo- but not after levodopa- or rotigotine.Discussion: Homocysteine elevation results from hepatic and gastrointestinal methylation processes. Transdermal rotigotine circumvents these methylation locations. Turnover of segregated alkyl residuals from rotigotine serves as methyl group donors, which counteract homocysteine increment. Th...

Oxidative stress is influenced by the thiol homeostasis, which regulates the redox milieu via glutathione. Components of glutathione metabolism are cysteine and cysteinyl-glycine. Both substrates decay following levodopa application or dopamine-related oxidative stress. Objective was to investigate the impact of an acute levodopa application with and without catechol-O-methyltransferase inhibitor on cysteine- and cysteinyl-glycine plasma levels. On two investigation days, 13 patients with Parkinson's disease took one retarded release 200-mg levodopa/50 mg carbidopa-containing tablet or one 150-mg levodopa/50-mg carbidopa/200-mg entacapone formulation under standardized conditions. Levodopa, 3-O-methyldopa, cysteine and cysteinyl-glycine were measured at baseline, 80 and 140 min following levodopa administration. Cysteine and cysteinyl-glycine similarly decreased, levodopa was nearly equal during both conditions. Entacapone lowered 3-O-methyldopa. Cysteine decay may be due to an elevated glutathione generation, which consumes cysteine. Cysteinyl-glycine decrease results from the alternative glutathione transformation to its oxidized form glutathione dissulfide after free radical scavenging.

Objective Magnetic resonance imaging is a non-invasive method that allows the indirect quantification of manganese (Mn) and iron (Fe) accumulation in the brain due to their paramagnetic features. The WELDOX II study aimed to explore the influence of airborne and systemic exposure to Mn and Fe on the brain deposition using the relaxation rates R1 and R2* as biomarkers of metal accumulation in regions of interest in 161 men, including active and former welders. Material and methods We obtained data on the relaxation rates R1 and R2* in regions that included structures within the globus pallidus (GP), substantia nigra (SN), and white matter of the frontal lobe (FL) of both hemispheres, as well as Mn in whole blood (MnB), and serum ferritin (SF). The study subjects, all male, included 48 active and 20 former welders, 41 patients with Parkinson's disease (PD), 13 patients with hemochromatosis (HC), and 39 controls. Respirable Mn and Fe were measured during a working shift for welders. Mixed regression models were applied to estimate the effects of MnB and SF on R1 and R2*. Furthermore, we estimated the influence of airborne Mn and Fe on the relaxation rates in active welders. Results MnB and SF were significant predictors of R1 but not of R2* in the GP, and were marginally associated with R1 in the SN (SF) and FL (MnB). Being a welder or suffering from PD or HC elicited no additional group effect on R1 or R2* beyond the effects of MnB and SF. In active welders, shift concentrations of respirable Mn > 100 μg/m3 were associated with stronger R1 signals in the GP. In addition to the effects of MnB and SF, the welding technique had no further influence on R1. Conclusions MnB and SF were significant predictors of R1 but not of R2*, indicative of metal accumulation, especially in the GP. Also, high airborne Mn concentration was associated with higher R1 signals in this brain region. The negative results obtained for being a welder or for the techniques with higher exposure to ultrafine particles when the blood-borne concentration was included into the models indicate that airborne exposure to Mn may act mainly through MnB.

Die alteste, wirksamste und am besten vertragliche Substanz zur Behandlung von Parkinson-Patienten im Rahmen einer dopaminergen Stimulation ist Levodopa (LD). Die kurze Halbwertszeit von LD wird jedoch als Faktor in der Entstehung von motorischen Langzeitkomplikationen angesehen. Aus diesem Grund wird die Therapie mit LD erst spat begonnen. Die zunachst aufgrund pharmakokinetischer und tierexperimenteller Untersuchungen angenommene Verzogerung dieser motorischen Komplikationen unter Kombination aus LD mit Carbidopa (CD) und Entacapon (EN), einem Hemmer der Catechol-O-Methyltransferase (COMT), konnte anhand der STRIDE-PD Studie nicht bestatigt werden. Unter COMT-Hemmung konnte eine bessere Symptomkontrolle mit konsekutiv verbesserter Lebensqualitat beobachtet werden. Das Auftreten von motorischen Fluktuationen war jedoch in dieser Gruppe fruher beobachtet worden. Weitere kleine, standardisierte Studien beschreiben einen moglichen Einfluss der COMT-Hemmung auf Kognition und Muskelkraft, wobei erganzende Untersuchungen hierzu ausstehen. Ferner wurden Anhaltspunkte fur eine Reduktion der Homozystein-Synthese unter Kombination von COMT-Hemmung und LD-Gabe beschrieben. Neben der 3-fach Kombination LD/CD/EN stehen die COMT-Hemmer Tolcapon (TO) und EN zur Verfugung. Die vorliegenden Sicherheitsdaten von EN im Vergleich zu TO fuhren aktuell zum Vorzug von EN, auch wenn die Gabe von TO wahrscheinlich eine bessere Wirksamkeit bietet. Die aktuelle Indikation zur COMT-Hemmung unter LD Therapie bei M. Parkinson, bleibt in der Behandlung von „wearing off“ und anderen motorischen Komplikationen wie z. B. Fluktuationen. Neue therapeutische Ansatze bedingt durch ein besseres Verstandnis des Enzyms und seiner Funktionen bleiben abzuwarten.

Oxidative stress is influenced by the thiol homeostasis, which determines the redox milieu. One of its components is Cysteinyl-glycine (Cys-Gly) generation, as its metabolic precursor is the free radicals scavenging glutathione. Levodopa is under suspicion to promote oxidative stress via the turnover of its metabolite dopamine in abundant mitochondria. Objective was to investigate the impact of levodopa on Cys-Gly plasma metabolism. Fifteen patients with Parkinson's disease orally took one 200-mg levodopa/50-mg carbidopa (CD) containing tablet. Levodopa, its derivative 3-O-methyldopa (3-OMD), and free Cys-Gly were measured at baseline, 60 and 120 min following levodopa/CD administration. Cys-gly concentrations decreased, levodopa and 3-OMD levels increased. Inverse relationships appeared between computed differences of Cys-gly and 3-OMD bioavailability. We conclude that Cys-Gly decline is related to levodopa metabolism to 3-OMD. Cys-Gly decay may result from the alternative transformation of glutathione to its oxidized form glutathione dissulfide as consequence of free radical scavenging.

Background: Parkinson’s disease (PD) is traditionally characterized as a movement disorder; however, sensory perception problems including pain syndromes are also frequent. We performed a survey to analyze the relations between health status, pain perception and gender in 4,086 PD patients. Moreover, the participants should tick whether they took pain medications or not. Subjects and Methods: The questionnaire included the EQ-5D and visual analogue scales (VAS) on pain, which asked for mean (VAS A), most (VAS B), and minimal (VAS C) intensity of pain during an interval of 4 weeks prior to the completion of the survey. Results: PD patients were divided into three groups according to their EQ-5D total score (I: Conclusions: Pain is associated with the health status of PD patients and worsens it. More female than male PD patients have to deal with handling of pain and pain drug treatment.

Application of oral fast release amantadine and levodopa may induce an improvement of motor symptoms in patients with Parkinson’s disease (PD). The objective of this trial was to investigate the clinical efficacy of a fast release amantadine sulfate formulation on simple and complex movement performance and putative relations to the pharmacokinetic behavior in PD patients. We challenged two cohorts of 12 PD patients, who were taken off their regular antiparkinsonian treatment for at least 12 hours, with oral 300 mg amantadine sulfate. We scored motor symptoms and performed instrumental tasks, which ask for performance of simple or complex motion series under cued conditions. Motor symptoms and performance of complex movements significantly improved in contrast to the carrying-out of simple motions. N-methyl-D-aspartic acid antagonistic and dopaminomimetic amantadine also influences altered higher predominant prefrontal cognitive functions. Therefore, performance of complex motion series improved, whereas carrying-out of simple repetitive movements is more associated to the striatal dopamine dependent basal ganglia function.

Background Following cued levodopa (LD) intake, endurance exercise showed a beneficial effect on scored motor performance in patients with Parkinson9s disease (PD) in comparison with rest. This may result from an exercise induced increase in endogenous dopamine synthesis. As a result, beneficial effects on movement and reactivity may occur. Objectives To measure reactivity and motor performance in a repeated fashion with instrumental tasks after cued administration of soluble 200 mg of LD/50 mg of benserazide. Design PD patients consecutively performed paradigms, which assess reactivity and movement performance, after a standardised period of rest or of age-related, heart rate adapted endurance exercise on two consecutive days in a random order. Results Reactivity and execution of simple and complex motion series were significantly better following exercise than after rest. Discussion Endurance exercise has a beneficial effect on reactivity and movement behaviour in PD patients following cued application of LD probably due to an augmented synthesis and release of dopamine and other catecholamines and release in the prefrontal cortex, the nucleus accumbens and the basal ganglia. Small changes in catecholamine modulation of prefrontal cortex cells can have profound effects on the ability of the prefrontal cortex to guide behaviour. Previous exercise may also improve pedunculopontine nucleus function, which is involved in motor-related attention processes.

Chronic levodopa (LD)/dopadecarboxylase inhibitor (DDI) increases homocysteine generation as side reaction of O-methylation. Aim was to investigate the impact of the peripheral COMT inhibitor entacapone (EN) on plasma concentrations of homocysteine, LD and 3-O-methyl-dopa (3-OMD). Patients with Parkinson's disease (PD) received on two consecutive days in a standardised fashion one single dose of 200 mg retarded release LD/carbidopa (CD) or of 150 mg LD/CD/EN, since both were shown to have simultaneous pharmacokinetic LD behaviour. Homocysteine increased after retarded release LD/CD application, but not following LD/CD/EN intake. Homocysteine was lower during the LD/CD/EN condition 80 min after baseline when compared with its levels after LD/CD administration. LD levels simultaneously rose on both days. 3-OMD concentrations did not change. Acute LD/CD application caused a rise of homocysteine levels, which was prevented by LD/CD/EN intake. Therefore, peripheral COMT inhibition may have a beneficial effect on putative, controversially debated components of homocysteine-related progression of PD.

A matter of debate is the impact of levodopa (LD) application in patients with Parkinson disease (PD) on altered force development and coordination, which are also influenced by the strength of muscles used. The objectives were to compare the motor response, the development of grip strength, and the pharmacokinetic behavior of LD and its main peripheral metabolite 3-O-methyldopa (3-OMD) after intake of 200-mg retarded-release levodopa/carbidopa (LD/CD) and of 150-mg LD/CD/entacapone (LD/CD/EN). Twelve patients with PD received both LD formulations within a standardized setting under double-blind conditions with a crossover design 1 day after the other. Motor symptoms significantly improved, LD plasma concentrations went up, and grip strength increased after both LD/CD and LD/CD/EN administration. There were no significant differences between both conditions with regard to motor response and LD pharmacokinetics. The 3-OMD levels were significantly lower during catechol-O-methyltransferase (COMT) inhibition with entacapone. The LD/CD/EN compound was superior over the retarded-release LD formulation, indicating the impact of LD on grip force. This may be caused by the interference of 3-OMD with the blood-brain barrier transport of LD; therefore, LD delivery is greater during the LD/CD/EN condition. Because the rating scale used does not consider the grip strength, this effect of better blood barrier transport of LD was not reflected. Another hypothesis may be that more acidic metabolites appear during peripheral LD metabolism by means of COMT, whereas COMT inhibition is accompanied by more basic LD metabolites (ie, the tyrosine aminotransferase-dependent substrates dihydroxyphenylpyruvate acetate and trihydroxyphenylacetate). This antiacid scenario may support a better muscle function with a positive impact on muscle excitability and contractibility.

Levodopa (LD) application improves motor symptoms and reduces cortisol levels in patients with Parkinson's disease (PD). Endurance exercise enhances cortisol release in proportion to the intensity of the effort and thus may counteract the LD associated cortisol decrease. We measured levels of cortisol and LD over an 1-h long interval following administration of soluble 200 mg LD/50 mg benserazide with concomitant maximal grip strength assessment in 16 PD patients under cued conditions during rest and endurance exercise. The motor response, the plasma levels of cortisol and LD did not significantly differ between both conditions. Cortisol concentrations significantly decreased even during exercise. Grip strength only significantly went up during rest. Endurance exercise did not counteract the LD associated decreased cortisol release. Since cortisol improves muscle function, the lack of increase in maximal grip strength following LD administration during exercise may contribute to reduced exercise capacity, which is reported by PD patients.

Acute levodopa (LD) application and exercise release human growth hormone (GH). An earlier trial showed, that combined stimulus of exercise and LD administration is the best provocative test for GH response in healthy participants. Objective was to show this combined effect of LD application and exercise on GH response and to investigate the impact on LD metabolism in 20 previously treated patients with Parkinson's disease (PD). We measured GH- and LD plasma concentrations following soluble 200 mg LD/50 mg benserazide administration during endurance exercise and rest on two separate consecutive days. GH concentrations significantly increased on both days, but GH release was significantly delayed during rest. LD metabolism was not altered due to exercise in a clinical relevant manner. Exercise induced a significant faster LD stimulated GH release in comparison with the rest condition. We did not find the supposed increase of LD induced GH release by endurance exercise. We assume, that only a limited amount of GH is available for GH release in the anterior pituitary following an acute 200 mg LD administration. GH disposal also depends on growth hormone releasing hormone (GHRH), which is secreted into hypothalamic portal capillaries. During the exercise condition, the resulting higher blood pressure supports blood flow and thus GHRH transport towards the GH producing cells in the pituitary. This might additionally have caused the significant faster GH release during exercise.

The interval of line tracing performance is more associated to basal ganglia function due to the dependence on bradykinesia and rigidity. The other component of this task, the precision of execution of complex movement sequences, is more related to attention. We compared the motor response after once dosing of 200 mg retarded release LD (levodopa)/CD (carbidopa) and of 150 mg LD/CD/EN (entacapone) by rating of motor symptoms, by measurement of LD- and 3-O-methyldopa (3-OMD) plasma concentrations and by the outcomes of a line tracing task. Thirteen treated patients with Parkinson's disease (PD) took one of the two tested LD formulations on two consecutive days under randomised, double blind, identical standardised conditions. No significant differences appeared regarding rated motor response and LD plasma concentrations, but 3-OMD only significantly went up after LD/CD intake. LD/CD/EN was superior to LD/CD regarding the attention related components of line tracing probably due to a hypothetically increased dopamine occurrence at the prefrontal cortex, which guides human behaviour.

Background A possible strategy to prolong plasma metabolism of Levodopa/Carbidopa (LD/CD) is Entacapone addition (EN), which improves impaired motor behaviour in patients with Parkinson’s disease (PD). Aims of the study Objectives were to evaluate the clinical response to an increased dopaminergic substitution with EN by clinical rating and assessment of complex motions and to investigate the change of movement in PD patients during repeat drug administration during an eight hour interval. Methods We used peg insertion with a computer based device and clinical rating for assessment of motor function in 20 treated PD patients. They received LD/CD and then the same LD/CD dosage plus EN in a standardised, open label fashion. Results Motor scores and performance of the instrumental task were significantly better and the fluctuation of movement was less intense during the LD/CD/EN condition according to the motor test outcomes. Conclusion EN supplementation improves motor symptoms and provides a more continuous movement behaviour in PD patients.

Levodopa application improves motor symptoms in patients with Parkinson disease (PD). Levodopa induces lower cortisol plasma levels and decreases serotonergic activity in certain brain areas of fish. The objectives of this study were to perform repeat cortisol concentration measurements before and after the administration of soluble levodopa/benserazide (dose, 200 mg) in 32 patients with PD during an interval of 150 minutes. The cortisol concentrations significantly decreased after levodopa intake, particularly in the patients with more advanced stage of PD, but not in the less affected patients. There were significantly lower cortisol levels in the patients at the advanced stage of PD compared with those of the earlier patients with PD, particularly at -30, 0, and 90 minutes before/after levodopa application. Significant inverse relations were found between the cortisol levels and the Unified Parkinson Disease Rating Scale total score, particularly at 60 and 90 minutes after levodopa intake. Neurodegeneration occurs in striatal regions and in the brain stem of patients with PD. The 5-HT-containing neuronal terminals of the brain stem hypothetically mediate the cortisol level decrease after levodopa intake because these cells contain an important fraction of amino acid decarboxylase. Therefore, this compartment may be the site of enzymatic conversion of superfluous, exogenous levodopa to dopamine. Consequently, short-term levodopa administration also leads to levodopa uptake in these 5-HT-metabolizing neurons, which interferes with the 5-HT synthesis and may cause a decrease of 5-HT levels. These lower 5-HT levels reduce the hypothalamic function and, via the corticotropin axis, the subsequent peripheral cortisol release. Thus, levodopa-induced cortisol decrease may be related to PD progression.

The objective was to investigate the impact of exercise on absorption and efficacy of levodopa (LD) in patients with Parkinson's disease (PD). A soluble, immediate release LD formulation was given followed by exercise near the aerobic limit on one day to PD patients, who underwent the same procedure only at rest on the second day. LD plasma behavior did not significantly differ between both conditions, but the motor response was significantly better 120 and 150 min after LD intake on the day with exercise than on the day with rest. Moderate exercise increases clinical efficacy of LD.

Addition of the catechol-O-methyltransferase (COMT) inhibitor entacapone (EN) prolongs plasma metabolism of levodopa (LD). Objectives were to determine the clinical response after EN addition and the plasma degradation of LD and 3-O-methyldopa [3-OMD]. Not optimum treated hospitalised patients with Parkinson's disease received the same LD dosage on the first day only with carbidopa (CD) and on the second day with CD and EN (t.i.d.) within a standardised setting. We scored motor symptoms and measured LD- and 3-OMD levels on both days at fixed moments. Motor impairment significant better improved probably due to significant higher maximum concentrations [C(max)] and computed area under the curve values of LD levels during the LD/CD/EN condition. Time to C(max) of LD was significantly delayed after the first two LD/CD/EN intakes. An impact of EN on 3-OMD levels appeared. A possibly augmented LD absorption and a prolonged LD metabolism after EN supplementation may contribute to a more continuous LD delivery to the brain.

The short plasma half-life limits the antiparkinsonian efficacy of levodopa/carbidopa (LD/CD). Administration of LD/CD with the catechol-O-methyltransferase inhibitor entacapone in one tablet (LCE) may extend plasma half-life of LD and thus its effect on motor symptoms in patients with Parkinson's disease (PD). The objectives of this study were to monitor the motor response to a switch from LD/CD to LCE by a simultaneous performance of an instrumental motor test and rating of motor symptoms and to compare the LD plasma behavior between both conditions in terms of stability. Twenty-one treated PD patients received LD/CD and then the identical oral LD dosage of LCE within a standardized setting on 2 consecutive days. Rating better reflected the motor improvement after LD application than the instrumental test. Motor symptoms of PD patients decreased significantly more during the LCE than the LD/CD condition, probably due to significantly higher LD plasma levels and a significantly less pronounced fall of the LD concentrations following the second LD intake. Our study shows a more stable LD plasma behavior during LCE intake and accordingly a better effect on motor symptoms according to rating outcomes and motor test results to a lesser extent.

Previous pharmacokinetic trials with standard levodopa formulations showed a different behavior of levodopa degradation in plasma of patients with Parkinson's disease (PD) in various advanced stages. The objective of this trial was to compare levodopa plasma metabolism in PD patients with and without previous long-term levodopa intake after oral intake of a dispensable levodopa/benserazide formulation (DLB). The over a 150 min interval computed area under the curve values of levodopa plasma levels after DLB administration were significantly (ANCOVA: F(1,19) = 7.88, P = 0.01) higher in PD patients with chronic levodopa treatment compared to patients without prior levodopa treatment. The maximum plasma levodopa concentration did not differ (ANCOVA: F(1.19) = 1.17, P = 0.29). Long-term levodopa administration results in an increased levodopa plasma bioavailability in PD patients.

The author s found 6.5-fold reduced nerve growth factor (NGF) levels in the plasma of treated patients with Parkinson disease (PD) compared with healthy control subjects (P = 0.03). A significant positive correlation between levodopa and NGF plasma levels appeared after acute levodopa/benserazide administration. The data suggest that acute levodopa administration may contribute to an increase of NGF plasma concentrations, which are reduced in treated PD patients due to the ongoing disease process itself or chronic antiparkinsonian drug treatment.

Catechol-O-methyltransferase inhibitor addition to levodopa/carbidopa formulations improves motor symptoms and reduces levodopa fluctuations in patients with Parkinson’s disease. Objectives were to investigate the effects of entacapone and tolcapone on plasma behaviour of levodopa, its metabolite 3-O-methyldopa and on motor impairment. 22 patients orally received levodopa/carbidopa first, then levodopa/carbidopa/entacapone and finally levodopa/carbidopa plus tolcapone within a 4.5 h interval twice. Maximum concentration, time to maximum level and bioavailability of levodopa did not differ between all conditions each with 200 mg levodopa application as a whole. Catechol-O-methyltransferase inhibition caused less fluctuations and higher baseline levels of levodopa after the first intake and less 3-O-methyldopa appearance. The maximum levodopa concentrations were higher after the second levodopa intake, particularly with catechol-O-methyltransferase inhibition. The motor response to levodopa was better with catechol-O-methyltransferase inhibition than without, tolcapone was superior to entacapone. More continuous levodopa brain delivery and lower 3-O-methyldopa bioavailability caused a better motor response during catechol-O-methyltransferase inhibition.

BACKGROUND Levodopa (LD)/dopa decarboxylase inhibitor application increases 3-O-methyldopa (3-OMD) concentrations in association with methyl group transfers, which demand for the conversion of methionine to homocysteine. This accompanying reaction is partially reversible by methyl group-donating vitamins. OBJECTIVE The objective of this study was to investigate of the effect of methyl group-donating vitamins on 3-OMD synthesis in LD-treated patients with Parkinson disease. METHODS We determined LD, 3-OMD, and homocysteine plasma concentrations in relation to daily LD dosage administered orally or as duodenal infusion with and without vitamins. RESULTS Orally LD-treated patients with Parkinson disease had a lower LD dose compared with the ones on an LD infusion, but LD, 3-OMD, and homocysteine bioavailability was not different. The same 3-OMD and homocysteine accumulation despite the applied higher LD dosage during the infusion indicates a limited methylation capacity. Higher 3-OMD concentrations occurred during chronic vitamin supplementation, whereas the other parameters did not vary from the ones before vitamin intake. CONCLUSIONS Vitamin supplementation elevated methylation of LD to 3-OMD. We suggest that, to a certain extent, plasma levels of homocysteine may reflect methyl group donation resources, whereas 3-OMD concentrations may mirror methylation capacity.

Background Transcranial sonography (TCS) is a reliable and sensitive diagnostic tool for the discrimination between Parkinson’s disease (PD) and essential tremor (ET). Currently, a single axial mesencephalic examination plane is routinely used in the evaluation of Substantia nigra (SN) echogenicity. However, the SN can also be depicted in a second coronal examination plane. In addition, the M-mode tremor frequency determination (M-TFD) represents a further but not yet established sonographic examination tool, which might integrate into the diagnostics of extrapyramidal movement disorders. Aim To evaluate the usefulness of a new coronal examination plane in discriminating PD from ET, by comparing the predicted values of the established axial examination plane. Furthermore, the diagnostic sensitivity and specificity of combined assessment of TCS and M-TFD are evaluated. Methods Echogenic areas of the SN of 30 PD patients were determined by TCS using the standard axial as well as coronal planes. In both planes a cut-off-value [c]0,2 cm[b] was used to define SN-hyperechogenicity (SN+). Tremor frequencies of resting and postural tremor were quantified by a M-TFD examination protocol. Isolated postural tremor with a frequency [c]6 Hz was defined as a typical ET-finding. Results of 30 PD-patients were compared with the findings of 7 ET patients and of 13 healthy controls. Results Our standardized axial plane TCS protocol showed a sensitivity of 90%, a specificity of 80%, a positive predictive value (PPV) of 87% and a negative predictive value (NPV) of 84% in supporting the diagnosis of PD. Interestingly, the use of the new coronal examination plane revealed even superior values (sensitivity = 93%, specificity = 85%, PPV = 90%, NPV = 89%). The combined sonographic assessment of TCS and M-TFD provided best diagnostic efficacy (sensitivity = 90%, specificity = 95%, PPV = 96%, NPV = 86%). Conclusion In the present study, the application of a coronal examination plane improved the diagnostic precision of TCS in discriminating PD from ET. In the combination with sonographic determination of tremor frequency by M-TFD best discriminative results are achieved. Thus, the combined usage of coronal TCS and M-TFD should be considered in the future to optimally apply sonography techniques for the evaluation PD and ET.

The thiol homeostasis determines the redox milieu and thus scavenging of free radicals by antioxidants like glutathione (GSH). GSH is formed out of cysteine in combination with l -glycine and glutamine acid. An up regulation of free radical occurrence is looked upon as one key feature of chronic neurodegeneration. Levodopa (LD) is under suspicion to support synthesis of free radicals via the degradation of its derivative dopamine in abundant mitochondria. Objectives were to investigate the impact of LD on free cysteine turnover in plasma. 200 mg LD/50 mg carbidopa (CD) were administered to 13 patients with Parkinson's disease under standardised conditions. Plasma levels of LD and free cysteine were measured before, 60- and 80-min after the LD/CD application. Cysteine concentrations decayed, expectedly LD levels increased. Cysteine decrease may result from an up regulation of GSH synthesis to encounter augmented appearance of free radicals associated with LD turnover via mitochondrial monoaminooxidase.

Background Polyneuropathy is observed in treated patients with Parkinson disease. Peripheral axonal degeneration is related to nerve growth factor metabolism. The causes for this axonal degeneration and the role of levodopa itself are not known. Levodopa may experimentally exert supportive effects on nerve growth factor synthesis and on growth hormone production, a hormonal compound with regenerative potential. Objective The objective of this study was to investigate the effects of soluble 250-mg levodopa/benserazide administration on plasma occurrence of levodopa, nerve growth factor, and growth hormone in patients with Parkinson disease over an interval of 60 minutes. Results Levodopa moderately increased bioavailability of nerve growth factor and growth hormone combined with the rise of levodopa. Nerve growth factor data and levodopa values correlated to each other. Conclusions Axonal degeneration may not be due to levodopa itself, as levodopa supports production of nerve growth factor and of growth hormone. Both may complement each other for neuronal survival.

Elevation of plasma total homocysteine concentrations were observed in levodopa/dopa decarboxylase inhibitor (DDI)-treated patients with Parkinson’s disease (PD). Degradation of levodopa to 3-O-methyldopa via the enzyme catechol-O-methyltransferase (COMT) is a methyl group demanding reaction. It generates homocysteine from the methyl group donor methionine. But there are inconsistent outcomes, as most investigators determined homocysteine after an overnight washout of levodopa. They did not consider the acute effects of levodopa/DDI intake in relation with COMT inhibition on homocysteine bioavailability. The purpose of this study is to measure levels of homocysteine, levodopa, and its metabolite 3-O-methyldopa in plasma after reiterated oral levodopa/DDI administration with and without the COMT-inhibitor entacapone (EN). Sixteen PD patients received 100 mg levodopa/carbidopa three times on day 1 and with EN on day 2 under standardized conditions. Homocysteine concentrations increased on day 1 and generally over the whole interval. No significant ascent of homocysteine appeared on day 2 only. Levodopa bioavailability was higher on day 2 due to the COMT inhibition. No change of 3-O-methyldopa appeared between both days. The correlation coefficients between homocysteine, levodopa, and 3-O-methyldopa were higher on day 1 than on day 2. Rise of homocysteine does not only depend on the oral levodopa dose, but also on the acute intake of levodopa/DDI with or without COMT inhibition. Measurements of homocysteine should consider acute repeated levodopa/DDI applications, as homocysteine and metabolically related 3-O-methyldopa accumulate due to their long plasma half-life in contrast to short-living levodopa.

Levodopa/carbidopa (LD/CD) application elevates total plasma homocysteine (thcys). We determined thcys-, LD- and 3-O-methyldopa (3-OMD) concentrations in 28 patients with Parkinson’s disease (PD) on a LD/CD duodenal gel treatment. We found a distinct thcys increase (29.52 ± 28.98 μmol/l [median ± SD]) above the 15 μmol/l threshold and a significant (R = 0.7) correlation between LD and 3-OMD. thcys ascent was observed in relation with the onset of atherosclerosis, non-motor symptoms and polyneuropathy in PD patients in the long term.

Levodopa (LD) application improves motor symptoms and reduces cortisol levels in patients with Parkinson’s disease (PD). Endurance exercise enhances cortisol release in proportion to the intensity of the effort and thus may counteract the LD associated cortisol decrease. We measured levels of cortisol and LD over an 1-h long interval following administration of soluble 200 mg LD/50 mg benserazide with concomitant maximal grip strength assessment in 16 PD patients under cued conditions during rest and endurance exercise. The motor response, the plasma levels of cortisol and LD did not significantly differ between both conditions. Cortisol concentrations significantly decreased even during exercise. Grip strength only significantly went up during rest. Endurance exercise did not counteract the LD associated decreased cortisol release. Since cortisol improves muscle function, the lack of increase in maximal grip strength following LD administration during exercise may contribute to reduced exercise capacity, which is reported by PD patients.

Adjunction of the catechol-O-methyltransferase (COMT) inhibitor entacapone (EN) to levodopa/carbidopa (LD/CD) improves motor symptoms in patients with Parkinson disease (PD) by a prolonged elimination of LD. But it is not known whether EN addition influences gastric emptying and thus LD pharmacokinetics and pharmacodynamics. Objectives were to simultaneously determine plasma LD elimination, gastric emptying, and clinical response after a single intake of the same LD dosage as LD/CD--or as (LD/CD/EN) formulation on 2 consecutive days. In both groups, PD patients with delayed gastric emptying had significant lower LD plasma concentrations. Addition of EN did not influence gastric emptying but significantly improved motor response, which was not different for patients with delayed gastric emptying. However, with and without EN adjunction gastric emptying distinctly contributes to the variability of plasma LD bioavailability. This may impact LD delivery to the brain and thus motor response in PD patients. Therefore, fine tuning of LD application, which considers gastric emptying, becomes more and more essential in advanced PD stages with a reduced striatal neuronal dopamine capacity, which is responsible for maintenance of motor response in early PD patients.

Levodopa (LD) application improves motor symptoms in patients with Parkinson’s disease (PD) patients. Little is known on further effects of LD, which induced lower plasma levels of cortisol and lower serotonergic activity in certain brain areas of fish. Objectives of this trial were to analyse levels of cortisol, LD and 3-O-methyldopa (3-OMD) after administration of LD/benserazide in long term treated PD patients. 12 PD patients, taken off their regular treatment for at least 12 hours, received soluble 200 mg LD/50 mg benserazide under stress free conditions. Motor symptoms improved, LD and 3-OMD levels increased, whereas cortisol concentrations started to decrease significantly 30 minutes after LD intake. This reduced cortisol release may result from an overflow of exogenous LD in the brainstem. This hypothetically causes an reduced 5-HT content in neurons projecting to the hypothalamic structures, which are involved in the partial 5-HT dependent central regulation of peripheral cortisol release.

Background: There is a debate about the deterioration of fine motor behavior during treatment with cholinesterase inhibitors. Methods: We used an instrumental motor test, which demands a complex motion series. Thereby we assessed motor function in patients with Alzheimer's disease (AD), in patients with mild cognitive impairment (MCI), and in controls. We also performed this task and a complex reaction time paradigm (CRT) during a six-week open-label safety study using transdermal delivery of the cholinesterase inhibitor rivastigmine. Objectives: To investigate (1) the performance of complex movements during deterioration of cognitive function and (2) the impact of rivastigmine on fine motor behavior and CRT outcomes in AD patients. Results: There were significant differences in the motor test outcomes, particularly when performed with the left non-dominant hand, between controls and patients with AD and MCI. Rivastigmine did not deteriorate assessed fine motor skills and CRT results. Conclusion: Our study shows an impaired carrying out of complex motion series during neurodegeneration associated with cognitive dysfunction. Rivastigmine selectively inhibits the predominant cortical and hippocampal Gl cholinesterase isoform; therefore, hypothetically no deterioration of fine motor behavior appeared during transdermal rivastigmine treatment. We assume that a putative drug-induced increase in speed and attention did not offset a deterioration of motion performance because we found no significant changes in the CRT results.

The short plasma half-life limits the antiparkinsonian efficacy of levodopa/carbidopa (LD/CD). Administration of LD/CD with the catechol-O-methyltransferase inhibitor entacapone in one tablet (LCE) may extend plasma half-life of LD and thus its effect on motor symptoms in patients with Parkinson's disease (PD). The objectives of this study were to monitor the motor response to a switch from LD/CD to LCE by a simultaneous performance of an instrumental motor test and rating of motor symptoms and to compare the LD plasma behavior between both conditions in terms of stability. Twenty-one treated PD patients received LD/CD and then the identical oral LD dosage of LCE within a standardized setting on 2 consecutive days. Rating better reflected the motor improvement after LD application than the instrumental test. Motor symptoms of PD patients decreased significantly more during the LCE than the LD/CD condition, probably due to significantly higher LD plasma levels and a significantly less pronounced fall of the LD concentrations following the second LD intake. Our study shows a more stable LD plasma behavior during LCE intake and accordingly a better effect on motor symptoms according to rating outcomes and motor test results to a lesser extent.

Instrumental tests and clinical rating assess motor disability in Parkinson’s disease (PD) patients. Previous long-term dopaminergic substitution influences the behaviour following acute dopaminergic stimulation. Objective of this study was to investigate the motor response following an apomorphine application in previously untreated-, treated- and before treated PD patients , who received placebo. Outcomes of instrumental tests worsened in previously untreated-, but not in before treated PD patients after apomorphine injection and in the PD subjects under the placebo condition . Generally, rating scores of motor symptoms significantly improved after apomorphine administration, whereas placebo application showed no effects. Tolerance to sedative effects of apomorphine in treated PD patients or sensitivity of employed motor tests to presynaptic dopaminergic autoreceptor mediated inhibition of endogenous dopamine release or postsynaptic dopaminergic overstimulation with resulting decreased cognitive function in previously untreated PD patients hypothetically caused this discrepancy between outcomes of subjective clinical rating and objective motor test performance.

Instrumental assessment of movements with a computer based device reflect the clinical response of patients with Parkinson’s disease (PD) to dopaminergic stimulation. We investigated associations between levodopa plasma levels, scored motor symptoms of upper limbs and instrumental test outcomes after dopaminergic stimulation. Clinical rating scores, test outcomes for simple and complex motion series significantly improved after oral application of 250 mg of a water soluble, fast absorbed levodopa/benserazide preparation, which induced a significant increase of levodopa in plasma during a two hour interval. There was a significant association between the computed area under the curve-values of levodopa plasma concentrations and test results for simple-, but not for complex movement sequences. Performance of complex motion series additionally ask for concomitant cognitive efforts with consecutive hypothetical involvement of extranigral non dopaminergic systems. In contrast, practice of simple movements is more directly associated to the predominantly dopamine regulated motor system.