Role of dopamine agonists in Parkinson's disease therapy.

Dopamine agonists are an important component of Parkinson's therapy. When weighing up the various therapy options, therapy with levodopa has recently been increasingly preferred due to its stronger efficacy and the ostensibly lower rate of side effects. The advantage of the lower incidence of motor complications during therapy with dopamine agonists was neglected. The occurrence of side effects can be explained by the different receptor affinity to the individual dopaminergic and non-dopaminergic receptors of the individual dopamine agonists. However, the different affinity to individual receptors also explains the different effect on individual Parkinson symptoms and can, therefore, contribute to a targeted use of the different dopamine agonists. Since comparative studies on the differential effect of dopamine agonists have only been conducted for individual substances, empirical knowledge of the differential effect is of great importance. Therefore, the guidelines for the treatment of Parkinson's disease do not consider the differential effect of the dopamine agonists. The historical consideration of dopamine agonists within Parkinson's therapy deserves special attention to be able to classify the current discussion about the significance of dopamine agonists.

S1 guidelines "lumbar puncture and cerebrospinal fluid analysis" (abridged and translated version).

INTRODUCTION: Cerebrospinal fluid (CSF) analysis is important for detecting inflammation of the nervous system and the meninges, bleeding in the area of the subarachnoid space that may not be visualized by imaging, and the spread of malignant diseases to the CSF space. In the diagnosis and differential diagnosis of neurodegenerative diseases, the importance of CSF analysis is increasing. Measuring the opening pressure of CSF in idiopathic intracranial hypertension and at spinal tap in normal pressure hydrocephalus constitute diagnostic examination procedures with therapeutic benefits.Recommendations (most important 3-5 recommendations on a glimpse): The indications and contraindications must be checked before lumbar puncture (LP) is performed, and sampling CSF requires the consent of the patient.Puncture with an atraumatic needle is associated with a lower incidence of postpuncture discomfort. The frequency of postpuncture syndrome correlates inversely with age and body mass index, and it is more common in women and patients with a history of headache. The sharp needle is preferably used in older or obese patients, also in punctures expected to be difficult.In order to avoid repeating LP, a sufficient quantity of CSF (at least 10 ml) should be collected. The CSF sample and the serum sample taken at the same time should be sent to a specialized laboratory immediately so that the emergency and basic CSF analysis program can be carried out within 2 h.The indication for LP in anticoagulant therapy should always be decided on an individual basis. The risk of interrupting anticoagulant therapy must be weighed against the increased bleeding risk of LP with anticoagulant therapy.As a quality assurance measure in CSF analysis, it is recommended that all cytological, clinical-chemical, and microbiological findings are combined in an integrated summary report and evaluated by an expert in CSF analysis. CONCLUSIONS: In view of the importance and developments in CSF analysis, the S1 guideline "Lumbar puncture and cerebrospinal fluid analysis" was recently prepared by the German Society for CSF analysis and clinical neurochemistry (DGLN) and published in German in accordance with the guidelines of the AWMF (https://www.awmf.org). /uploads/tx_szleitlinien/030-141l_S1_Lumbalpunktion_und_Liquordiagnostik_2019-08.pdf). The present article is an abridged translation of the above cited guideline. The guideline has been jointly edited by the DGLN and DGN.

Polypharmacy in Parkinson's disease: risks and benefits with little evidence.

Polypharmacy is common practice in Parkinson's disease. Medical treatment targeting the dopaminergic system alone may include up to five different compounds: L-DOPA (in combination with a DOPA decarboxylase inhibitor), a catechol-O-methyltransferase (COMT) and a monoamine oxidase (MAO-B) inhibitor and a dopamine agonist. Particular motor and non-motor symptoms may require additional specific therapeutics, such as drugs aimed at tremor control and to treat depression, dementia and orthostatic and autonomic dysfunction. No prospective studies have yet been performed with regard to the efficacy or the long-term benefit of combining such different treatments in Parkinson's disease and retrospective analyses are sparse. We thus tried to compile the available evidence for polypharmacy strategies in Parkinson's disease and devised an expert opinion statement.

[Parkinson's Disease at the Border Between Inpatient and Outpatient Care]. / Das idiopathische Parkinson-Syndrom an der Grenze von ambulanter zu stationärer Versorgung.

Parkinson's disease is characterized by a continuous spectrum of varying severity. The treatment is driven by new and sometimes highly complex therapeutic procedures. These two aspects are responsible for the blurred dividing line between outpatient and inpatient care. The aim of this article is to define criteria that should help determine the indication for inpatient or outpatient treatment. We introduce quality requirements that have already been taken into account in part in therapy modalities such as Parkinson complex treatment. The decision on the appropriate form of care affects the medical freedom of therapy, which must reconcile the legitimate interest of patients to receive optimal care with the given economic conditions. Our aim is to provide guidance on decisions on the best form of treatment in the context of changing framework conditions in the health sector.

Loss of DJ-1 impairs antioxidant response by altered glutamine and serine metabolism.

The oncogene DJ-1 has been originally identified as a suppressor of PTEN. Further on, loss-of-function mutations have been described as a causative factor in Parkinson's disease (PD). DJ-1 has an important function in cellular antioxidant responses, but its role in central metabolism of neurons is still elusive. We applied stable isotope assisted metabolic profiling to investigate the effect of a functional loss of DJ-1 and show that DJ-1 deficient neuronal cells exhibit decreased glutamine influx and reduced serine biosynthesis. By providing precursors for GSH synthesis, these two metabolic pathways are important contributors to cellular antioxidant response. Down-regulation of these pathways, as a result of loss of DJ-1 leads to an impaired antioxidant response. Furthermore, DJ-1 deficient mouse microglia showed a weak but constitutive pro-inflammatory activation. The combined effects of altered central metabolism and constitutive activation of glia cells raise the susceptibility of dopaminergic neurons towards degeneration in patients harboring mutated DJ-1. Our work reveals metabolic alterations leading to increased cellular instability and identifies potential new intervention points that can further be studied in the light of novel translational medicine approaches.

Unchanged gastric emptying and visceral perception in early Parkinson's disease after a high caloric test meal.

Delayed gastric emptying (GE) is a frequent non-motor feature in Parkinson´s disease (PD). This prospective study (clinicaltrials.gov Identifier NCT01518751) investigated GE and visceral perception in early motor phase PD patients in comparison to age-matched and younger controls. In addition, the effect of Levodopa on GE was assessed in healthy aged controls. 16 PD patients (Hoehn & Yahr 2), 11 sex-/age-matched Ctrl1 and 10 young, male Ctrl2 subjects were subjected to a high caloric (428 kcal) (13)C-Sodium Octanoate breath test strictly OFF dopaminergic medication. Visceral appetite sensation was monitored using visual analogue scales (VAS). GE was similarly studied in 7 controls ON/OFF oral Levodopa. GE was not altered in PD patients compared to age-/sex-matched and younger controls (p = 0.76). Subjective appetite perception was not altered in the PD group in comparison to Ctrl1, but was significantly higher in Ctrl2 subjects (p = 0.02). 100 mg oral Levodopa/25 mg Benserazide significantly slowed GE by 18% among healthy controls (p = 0.04). In early motor stage PD OFF dopaminergic medication, there was no GE slowing after a high caloric test meal. Levodopa, however, caused a robust GE slowing in healthy aged individuals. Our data indicate that clinically relevant GE slowing in early PD is related to the iatrogenic effect of dopamine treatment. Subjective appetite perception is not affected in this disease stage. This data add to the understanding of gastrointestinal symptoms in early motor stage PD and highlight the influence of dopaminergic medication.

Sarcoid neuropathy: correlation of nerve ultrasound, electrophysiological and clinical findings.

INTRODUCTION: We present the nerve ultrasound findings in sarcoid neuropathy and examine their correlation with electrophysiology and functional disability. MATERIALS AND METHODS: 40 healthy controls and 13 patients with sarcoid neuropathy underwent clinical, sonographic and electrophysiological evaluation, a mean of 2.1 years (SD ± 0.7) after disease onset. RESULTS: Nerve ultrasound revealed significantly higher cross sectional area (CSA) values of the ulnar (elbow, p<0.001), fibular (fibular head, p<0.001), sural (between the lateral and the medial head of the gastrocnemius muscle, p<0.001) and tibial nerves (ankle and popliteal fossa, p<0.001), when compared to controls. The electroneurography documented significantly lower values of the 1) compound muscle action potentials (cMAPs) in the median, fibular and tibial nerves (p<0.001), and 2) sensory nerve action potential (sNAP) in the median, ulnar and sural nerves (p<0.001). A significant correlation between sonographic and electrophysiological findings in the group with sarcoid neuropathy was found only between cMAP and CSA of the ulnar nerve at the elbow (r=0.894, p<0.001). Neither nerve sonography nor electrophysiology correlated with functional disability. DISCUSSION: Sarcoid neuropathy seems to show predominantly CSA enlargement in peripheral nerves of the lower extremities, without any significant correlation to electrophysiological findings. The electroneurography documented signs of sensorimotor axonal loss in various peripheral nerves. Neither nerve sonography nor electrophysiology correlated with functional disability.

Mitochondrial proteolytic stress induced by loss of mortalin function is rescued by Parkin and PINK1.

The mitochondrial chaperone mortalin was implicated in Parkinson's disease (PD) because of its reduced levels in the brains of PD patients and disease-associated rare genetic variants that failed to rescue impaired mitochondrial integrity in cellular knockdown models. To uncover the molecular mechanisms underlying mortalin-related neurodegeneration, we dissected the cellular surveillance mechanisms related to mitochondrial quality control, defined the effects of reduced mortalin function at the molecular and cellular levels and investigated the functional interaction of mortalin with Parkin and PINK1, two PD-related proteins involved in mitochondrial homeostasis. We found that reduced mortalin function leads to: (1) activation of the mitochondrial unfolded protein response (UPR(mt)), (2) increased susceptibility towards intramitochondrial proteolytic stress, (3) increased autophagic degradation of fragmented mitochondria and (4) reduced mitochondrial mass in human cells in vitro and ex vivo. These alterations caused increased vulnerability toward apoptotic cell death. Proteotoxic perturbations induced by either partial loss of mortalin or chemical induction were rescued by complementation with native mortalin, but not disease-associated mortalin variants, and were independent of the integrity of autophagic pathways. However, Parkin and PINK1 rescued loss of mortalin phenotypes via increased lysosomal-mediated mitochondrial clearance and required intact autophagic machinery. Our results on loss of mortalin function reveal a direct link between impaired mitochondrial proteostasis, UPR(mt) and PD and show that effective removal of dysfunctional mitochondria via either genetic (PINK1 and Parkin overexpression) or pharmacological intervention (rapamycin) may compensate mitochondrial phenotypes.

Treatment approaches of gastrointestinal dysfunction in Parkinson's disease, therapeutical options and future perspectives.

Gastrointestinal (GI) dysfunction is a common but underestimated feature in Parkinson's disease (PD). Out of the multimodal spectrum of treatment options, there currently are only a few pharmacological treatments available to improve gastrointestinal motility and symptoms. Because enteric nervous function is mainly regulated by transmitters different from those involved in the brain, dopamine replacement is not a treatment option in PD patients. This article focuses on the known regulative mechanism of GI function and presents known and upcoming treatment options for GI dysfunction in PD.

Quality of life, caregiver burden and insurance in patients with Parkinson's disease in Germany.

BACKGROUND: German health politicians claim that maintenance and thus quality of life (QoL) of patients with chronic disease do not differ between the various healthcare insurance systems in Germany. Patient organizations i.e. the Deutsche Parkinson Vereinigung for patients with Parkinson's disease (PD), physicians, patients themselves and their carers controversially discuss this opinion making by politicians. METHODS: We performed a survey to analyse the relations between QoL, insurance, disability and caregiver burden in 2603 patients with PD and their carers. RESULTS: Insurance with private reimbursement provides a significant better self-reported patient disability and QoL according to the various employed rating instruments in patients with PD. Government employees with PD, who have additional private insurance, demand for significant shorter intervals of care giving by their carers. In general, caregiver burden did not significantly differ between patients with PD of the different healthcare insurance systems. CONCLUSION: At least in Germany, obligatory medical insurance with associated state regulation of health care is inferior to private reimbursement insurance in various domains of QoL.

[Transcraniel ultrasound in the differential diagnosis of Parkinson's disease]. / Stellenwert der Hirnparenchym-Sonografie in der Differenzial- und Frühdiagnose des Parkinson-Syndroms.

Imaging of the brain structure with transcranial ultrasound has become an important tool for the diagnosis and differential diagnosis of Parkinson's Disease. In up to 90 % of parkinsonian patients abnormal echogenity of the substantia nigra could be demonstrated. Particularly in the early diagnosis in subjects with only very mild extrapyramidal features and in the differential diagnosis to other neurodegenerative disorders with parkinsonian features, such as the parkinsonian variant of multisystematrophy (MSA-P) and progressive supranuclear paralysis (PSP) ultrasound has a high diagnostic yield. Because of a prevalence of about 10 % in the normal population, the evidence of an abnormal echogenity of the substantia nigra has to be interpreted carefully in the context of a clinical examination. Although there are a number of studies indicating that in some of these subjects a vulnerability of the nigrostriatal system can be found, the meaning of an abnormal echogenicity of the substantia nigra in the healthy population needs to be further elucidated in already ongoing research projects.

Dystonia in neurodegeneration with brain iron accumulation: outcome of bilateral pallidal stimulation.

Neurodegeneration with brain iron accumulation encompasses a heterogeneous group of rare neurodegenerative disorders that are characterized by iron accumulation in the brain. Severe generalized dystonia is frequently a prominent symptom and can be very disabling, causing gait impairment, difficulty with speech and swallowing, pain and respiratory distress. Several case reports and one case series have been published concerning therapeutic outcome of pallidal deep brain stimulation in dystonia caused by neurodegeneration with brain iron degeneration, reporting mostly favourable outcomes. However, with case studies, there may be a reporting bias towards favourable outcome. Thus, we undertook this multi-centre retrospective study to gather worldwide experiences with bilateral pallidal deep brain stimulation in patients with neurodegeneration with brain iron accumulation. A total of 16 centres contributed 23 patients with confirmed neurodegeneration with brain iron accumulation and bilateral pallidal deep brain stimulation. Patient details including gender, age at onset, age at operation, genetic status, magnetic resonance imaging status, history and clinical findings were requested. Data on severity of dystonia (Burke Fahn Marsden Dystonia Rating Scale-Motor Scale, Barry Albright Dystonia Scale), disability (Burke Fahn Marsden Dystonia Rating Scale-Disability Scale), quality of life (subjective global rating from 1 to 10 obtained retrospectively from patient and caregiver) as well as data on supportive therapy, concurrent pharmacotherapy, stimulation settings, adverse events and side effects were collected. Data were collected once preoperatively and at 2-6 and 9-15 months postoperatively. The primary outcome measure was change in severity of dystonia. The mean improvement in severity of dystonia was 28.5% at 2-6 months and 25.7% at 9-15 months. At 9-15 months postoperatively, 66.7% of patients showed an improvement of 20% or more in severity of dystonia, and 31.3% showed an improvement of 20% or more in disability. Global quality of life ratings showed a median improvement of 83.3% at 9-15 months. Severity of dystonia preoperatively and disease duration predicted improvement in severity of dystonia at 2-6 months; this failed to reach significance at 9-15 months. The study confirms that dystonia in neurodegeneration with brain iron accumulation improves with bilateral pallidal deep brain stimulation, although this improvement is not as great as the benefit reported in patients with primary generalized dystonias or some other secondary dystonias. The patients with more severe dystonia seem to benefit more. A well-controlled, multi-centre prospective study is necessary to enable evidence-based therapeutic decisions and better predict therapeutic outcomes.

Comparison of 200 mg retarded release levodopa/carbidopa - with 150 mg levodopa/carbidopa/entacapone application: pharmacokinetics and efficacy in patients with Parkinson's disease.

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.

Prevalence and treatment strategies of dyskinesia in patients with Parkinson's disease.

A study into the prevalence and treatment of dyskinesia in Parkinson's disease (PD) patients was performed with 380 PD specialists' completed interviews relating to PD and retrospectively completed 1900 patient record forms for patients with dyskinesia. Physicians reported, that 34% of their PD patients experience dyskinesia, 57% of dyskinetic PD patients were affected by moderately-to-completely disabling dyskinesia. Treatment of dyskinesia was looked upon as not satisfactory, fractionating of levodopa dose was used as first choice therapeutic option of dyskinesia.

Mutation analysis of the seven in absentia homolog 1 (SIAH1) gene in Parkinson's disease.

Seven in absentia homolog 1 (SIAH-1) is a member of the RING-finger-containing E3 ubiquitin ligases. Two substrates of SIAH-1 are alpha-synuclein and synphilin-1, both of these proteins are involved in Parkinson's disease (PD). Recently, mutations in Parkin, another E3 ubiquitin ligase which ubiquinates synphilin-1 and glycosylated alpha-synuclein, have been defined as a major cause of autosomal recessive PD. The potential role of SIAH-1 in PD is further underlined as SIAH-1 protein is a component of the Lewy bodies and as it plays a role in apoptosis caused by nitric oxide (NO) induced oxidative stress. Thus, we performed a mutation screening of the SIAH-1 gene in PD patients. However, screening a large sample of 209 familial and sporadic PD patients we could not find any disease causing mutation. We therefore conclude that genetic alterations of SIAH-1 do not significantly contribute to the pathogenesis of PD.

Pharmacokinetic behaviour of levodopa and 3-O-methyldopa after repeat administration of levodopa/carbidopa with and without entacapone in patients with Parkinson's disease.

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.