Paola Imbriani

Rotigotine may improve sleep architecture in Parkinson's disease: a double-blind, randomized, placebo-controlled polysomnographic study

BACKGROUND/OBJECTIVES Growing evidence demonstrates that in Parkinsons Disease (PD) sleep disturbances are frequent and difficult to treat. Since the efficacy of rotigotine on sleep is corroborated by studies lacking polysomnography (PSG), this study explores the possible rotigotine-mediated impact on PSG parameters in PD patients. METHODS This is a randomized, double-blind, placebo-controlled, parallel-group study to determine the efficacy of rotigotine vs placebo on PSG parameters in moderately advanced PD patients. An unusual protocol was utilized, since patches were maintained from 18:00 h to awakening, minimizing the possible diurnal impact on motor symptoms. All participants underwent sleep PSG recordings, subjective sleep questionnaires (Parkinson Disease Sleep Scale [PDSS], Pittsburgh Sleep Quality Index [PSQI]), and the assessment of early-morning motor disability. RESULTS We evaluated 42 PD patients (Hoehn & Yahr stages 2 and 3) with sleep impairment randomly assigned to active branch (N =21) or placebo (N = 21). Rotigotine significantly increased sleep efficiency and reduced both wakefulness after sleep onset and sleep latency compared to placebo. Moreover, the mean change in REM sleep quantity was significantly higher in the rotigotine than placebo group. The improvement of PSG parameters corresponded to the amelioration of PDSS and PSQI scores together with the improvement of patient morning motor symptoms. CONCLUSIONS This study demonstrated the significant effect of rotigotine on sleep quality and continuity in PD patients by promoting sleep stability and increasing REM. The effectiveness of rotigotine on sleep may be ascribed to its pharmacokinetic/pharmacodynamic profile directly on both D1 and D2 receptors.

Serotonin Impairment in CSF of PD Patients, without an Apparent Clinical Counterpart

In Parkinsons disease (PD), several studies have detected an impaired serotonin (5-HT) pathway, likely affecting both motor and non-motor domains. However, the precise impact of 5-HT impairment is far from established. Here, we have used a HPLC chromatographic method, in a homogenous cohort (n = 35) of non fluctuating, non dyskinetic PD patients, to assess the concentration of 5-HT and its metabolite 5-HIAA in peripheral cerebrospinal fluid (CSF) obtained from lumbar puncture (LP). LP was performed following three days of therapy withdrawal, in order to vanish the effects of prolonged released dopamine agonists (DA), and in absence of any serotonergic agent. The PD patient group showed a significantly reduced CSF level of both 5-HT and 5-HIAA compared to either age-matched control subjects (n = 18), or Alzheimers disease patients (n = 20). However, no correlation emerged between 5-HT/5-HIAA concentrations and UPDRS-III (r = −0.12), disease duration (r = −0.1), age (r = −0.27) and MMSE (r = 0.11). Intriguingly, low CSF 5-HT levels did not differ for gender or for motor phenotype (in terms of non-tremor dominant subtype and tremor dominant subtype). Further, low CSF 5-HT levels did not correlate with the presence of depression, apathy or sleep disturbance. Our findings support the contention that 5-HT impairment is a cardinal feature of stable PD, probably representing a hallmark of diffuse Lewy bodies deposition in the brainstem. However, clinical relevance remains uncertain. Given these findings, an add-on therapy with serotonergic agents seems questionable in PD patients, or should be individually tailored, unless severe depression is present.

A clinical and biochemical analysis in the differential diagnosis of idiopathic normal pressure hydrocephalus

Introduction Idiopathic normal pressure hydrocephalus (iNPH) can be misdiagnosed with other neurodegenerative diseases, especially in the early disease stages. Considering the opportunity of the shunt surgery, iNPH should be diagnosed with accuracy. Here, we evaluate the utility of CSF biomarkers and their relationship with clinical features in the diagnosis of iNPH. Methods We performed a multivariate analysis of the CSF levels of Aβ42, t-tau, and p-tau collected from four groups of patients: 14 iNPH, 14 progressive supranuclear palsy (PSP), 14 Alzheimer’s disease (AD), 14 controls (CTL). Diagnostic accuracy of biomarkers was determined by the receiver operating characteristic curve analysis. Statistical correlation was calculated between each CSF biomarker and single clinical items of iNPH. Results Aβ42 levels in iNPH were lower than controls, although not as low as in AD. Likewise, CSF t-tau and p-tau were lower in iNPH than in controls. Of interest, t-tau and p-tau were higher in AD than in controls and hence both t-tau and p-tau were significantly lower in iNPH than in AD. No differences were found between iNPH and PSP. CSF biomarkers levels did not correlate to clinical features of iNPH, whereas two significant correlations emerged within clinical parameters: cognitive impairment was related to gait difficulties, while ventricular enlargement correlated with continence disturbances. Conclusion Measurement of CSF biomarker levels may be helpful in the differential diagnosis between iNPH and AD but not between iNPH and PSP. Both Aβ42 and tau levels appear unrelated to main clinical features of iNPH.

Heidenhain variant in two patients with inherited V210I Creutzfeldt-Jakob disease.

Objective: To report two members of the same family carrying the valine to isoleucine point mutation of the prion protein gene (PRNP) and presenting with visual symptoms as initial manifestation as in the “Heidenhain variant” of sporadic Creutzfeldt–Jakob disease (CJD). Methods: Patients underwent neurological examination, electroencephalogram (EEG), brain magnetic resonance images (MRI) and cerebrospinal fluid (CSF) analysis including the Real Time Quaking Induced Conversion (RT-QuIC) test. Disease-specific mutations and polymorphism at codon 129 of the PRNP gene were also studied. Results: Isolated visual symptoms characterized disease onset of both patients followed by progressive neurological signs, dementia and death in 3 (proband) and 9 (his aunt) months. RT-QuIC analysis of CSF samples of both patients revealed the presence of the pathological prion protein and DNA analysis the V210I point mutation of the PRNP and methionine homozygosity at the polymorphic codon 129. Conclusions: This report suggests to consider the diagnosis of V210I genetic CJD in patients presenting with the Heidenhain form of CJD and highlights the importance of genetic testing in all patients with isolated visual manifestations at onset followed by progressive neurological signs and dementia.

Cerebrospinal fluid biomarkers profile of idiopathic normal pressure hydrocephalus

Idiopathic normal pressure hydrocephalus (iNPH) is a disabling neurological disorder whose potential treatability is significantly limited by diagnostic uncertainty. In fact, typical clinical presentation occurs at late phases of disease, when CSF shunting could be ineffective. In recent years, measurement of different CSF proteins, whose concentration directly reflects neuropathological changes of CNS, has significantly improved both diagnostic timing and accuracy of neurodegenerative disease. Unfortunately iNPH lacks neuropathological hallmarks allowing the identification of specific disease biomarkers. However, neuropathology of iNPH is so rich and heterogeneous that many processes can be tracked in CSF, including Alzheimer’s disease core pathology, subcortical degeneration, neuroinflammation and vascular dysfunction. Indeed, a huge number of CSF biomarkers have been analyzed in iNPH patients, but a unifying profile has not been provided yet. In this brief survey, we thus attempted to summarize the main findings in the field of iNPH CSF biomarkers, aimed at outlining a synthetic model. Although defined cut-off values for biomarkers are not available, a better knowledge of CSF characteristics may definitely assist in diagnosing the disease.

Subtle alterations of excitatory transmission are linked to presynaptic changes in the hippocampus of PINK1-deficient mice

Homozygous or heterozygous mutations in the PTEN‐induced kinase 1 (PINK1) gene have been linked to early‐onset Parkinsons disease (PD). Several neurophysiological studies have demonstrated alterations in striatal synaptic plasticity along with impaired dopamine release in PINK1‐deficient mice. Using electrophysiological methods, here we show that PINK1 loss of function causes a progressive increase of spontaneous glutamate‐mediated synaptic events in the hippocampus, without influencing long‐term potentiation. Moreover, fluorescence analysis reveals increased neurotrasmitter release although our biochemical results failed to detect which presynaptic proteins might be engaged. This study provides a novel role for PINK1 beyond the physiology of nigrostriatal dopaminergic circuit. Specifically, PINK1 might contribute to preserve synaptic function and glutamatergic homeostasis in the hippocampus, a brain region underlying cognition. The subtle changes in excitatory transmission here observed might be a pathogenic precursor to excitotoxic neurodegeneration and cognitive decline often observed in PD. Using electrophysiological and fluorescence techniques, we demonstrate that lack of PINK1 causes increased excitatory transmission and neurotransmitter release in the hippocampus, which might lead to the cognitive decline often observed in Parkinsons disease. Synapse 70:223–230, 2016.

Rotigotine may control drooling in patients with Parkinson's Disease: Preliminary findings

OBJECTIVE To evaluate the efficacy of rotigotine in controlling the drooling of Parkinsons Disease (PD) patients. PATIENTS AND METHODS We assessed 7 PD patients (Hoehn and Yahr scale >2.5) with three different clinical scores (Drooling Severity and Frequency Scale - DSFS, Drooling Rating Scale - DRS and Sialorrhea Clinical Scale for PD - SCS) before and after 4 weeks of therapy. Statistical differences were analyzed with Wilcoxon signed-rank test. RESULTS We observed that rotigotine significantly improves drooling as measured by the lowering of the three scores (p<0.05). CONCLUSIONS Among non-motor symptoms of PD, drooling is one of the most embarrassing and disabling for patients. Current treatments are unsatisfactory and novel approaches are thus desirable. In this open-label pilot study we demonstrated on a small sample of patients that up to 4mg/24h of rotigotine, a non-ergolinic dopamine agonist with continuous transdermal delivery, may be helpful in the management of drooling in advanced PD.

Strength and Weaknesses of Cerebrospinal Fluid Biomarkers in Alzheimer’s Disease and Possible Detection of Overlaps with Frailty Process

With the increase of human lifespan and refinement of diagnostic techniques dementia, and Alzheimers disease (AD) in particular, have become a multi-decade process with a complex pathogenesis. The prognosis of AD patients, especially in late stages, may be strongly influenced by factors that go far beyond the well-recognized cascades (tau deposition, amyloid plaques). In this context, AD and Frailty, a multidimensional process of the elderly, inevitably overlap. Not surprisingly, the routine biomarkers collectable in the cerebrospinal fluid, while highly relevant in allowing specific diagnoses, becoming limiting when used to define severity and rate of progression of cognitive impairment. In reviewing merits and pitfalls of routine cerebrospinal fluid profile for AD, this manuscript will examine the state-of-the-art related to a parallel field, the extrapyramidal disorders. For synucleinopathies, we will discuss the possibility to detect factors directly involved in earliest disease pathology (alpha-synuclein, tau-proteins) together with indexes of disease progression (i.e. dopamine-metabolite ratio and loss of blood-brain barrier integrity). This approach might guarantee the capability of monitoring putative disease-modifying strategies. However, we will show the likelihood that nonconventional approaches already proposed for Frail subjects (such as exercise-mediated neuro-protection) might prove to be a useful aid for an ageing brain already impaired by AD alterations. A crucial test for these hypotheses would be to apply this sort of interventional, and not merely pharmacological, therapy to homogeneous patient cohorts.

Early structural and functional plasticity alterations in a susceptibility period of DYT1 dystonia mouse striatum

The onset of abnormal movements in DYT1 dystonia is between childhood and adolescence, although it is unclear why clinical manifestations appear during this developmental period. Plasticity at corticostriatal synapses is critically involved in motor memory. In the Tor1a+/Δgag DYT1 dystonia mouse model, long-term potentiation (LTP) appeared prematurely in a critical developmental window in striatal spiny neurons (SPNs), while long-term depression (LTD) was never recorded. Analysis of dendritic spines showed an increase of both spine width and mature mushroom spines in Tor1a+/Δgag neurons, paralleled by an enhanced AMPA receptor (AMPAR) accumulation. BDNF regulates AMPAR expression during development. Accordingly, both proBDNF and BDNF levels were significantly higher in Tor1a+/Δgag mice. Consistently, antagonism of BDNF rescued synaptic plasticity deficits and AMPA currents. Our findings demonstrate that early loss of functional and structural synaptic homeostasis represents a unique endophenotypic trait during striatal maturation, promoting the appearance of clinical manifestations in mutation carriers.

Continuous dopaminergic stimulation in a patient treated with daytime Levodopa-carbidopa intestinal gel and overnight Rotigotine: a case report.

Patients with Parkinson’s disease (PD) receiving long-term L-Dopa therapy eventually develop motor complications with unpredictable “on-off” response fluctuations and involuntary movements, leading to progressive disability. Hence, the search for alternative therapeutic choices based on continuous dopaminergic stimulation (CDS) becomes crucial for the treatment of advanced PD. Here, we describe the case of a 70-year-old man with a 9-year history of PD, treated with daytime levodopa-carbidopa intestinal gel (LCIG) and overnight Rotigotine transdermal patch. LCIG monotherapy significantly reduced motor fluctuations and prevented the appearance of unpredictable off periods; concurrently, overnight Rotigotine improved his sleep quality and morning akinesia. Both LCIG and Rotigotine induce CDS, which conceptually mimics physiologic striatal dopamine receptor function. Hence, they both represent a good therapeutic option for the treatment of advanced PD. (www.actabiomedica.it)