[Smell the smoke before one sees the fire-The oligosymptomatic prodromal phase of neurodegenerative diseases]. / Den Rauch riechen, bevor man das Feuer sieht ­ die oligosymptomatische Prodromalphase neurodegenerativer Erkrankungen.

BACKGROUND: With the increasing development of disease-modifying causative treatment, the importance of early diagnosis and detection of asymptomatic or oligosymptomatic early stages of neurodegenerative diseases is increasing. OBJECTIVE: Presentation of early stages of neurodegenerative diseases, diagnostic procedures for the early detection and possible treatment consequences. MATERIAL AND METHODS: Selective literature search, discussion of basic research and expert recommendations. RESULTS: Many neurodegenerative diseases have a prodromal phase preceding the manifest disease that can be diagnosed with current criteria. In this prodromal phase, those affected are often oligosymptomatic but in some cases can already be identified using biomarkers. These developments are already taken into account in diagnostic criteria for some of these prodromal phases. The prodromal phase, in turn, is preceded by an asymptomatic phase which, however, already shows molecular changes and can be identified by biomarkers in some diseases. The early identification and stratification of patients is particularly important when planning studies for disease-modifying treatment, and biomarkers are already being used in clinical trials for this purpose. DISCUSSION: Biomarker-based identification of individuals in the prodromal phase of neurodegenerative diseases is already possible for some entities. People who show the first signs of a neurodegenerative disease can be referred to centers for clinical trials and observational studies.

[How the implementation of a school for people with Parkinson's disease can succeed-Results of a consensus study and a formative evaluation]. / Wie die Umsetzung einer Schule für Menschen mit Parkinson-Krankheit gelingen kann ­ Ergebnisse eines Konsensusverfahrens und einer formativen Evaluation.

BACKGROUND: As the most rapidly increasing neurodegenerative disease worldwide, Parkinson's disease is highly relevant to society. Successful treatment requires active patient participation. Patient education has been successfully implemented for many chronic diseases, such as diabetes and could also provide people with Parkinson's disease with skills to manage the disease better and to participate in shared decision making. MATERIAL AND METHODS: To prepare the implementation of a concept for patient education for people with Parkinson's disease, a structured consensus study was conducted and a pilot project formatively evaluated. The structured consensus study included experts from all over Germany. It consisted of two online surveys and an online consensus conference. The formative evaluation was conducted as three focus groups. Transcripts were evaluated using content-structuring qualitative content analysis. RESULTS: From the consensus procedure 59 consented statements emerged, mainly regarding the contents of a patient school and a group size of 6-8 persons. Only two statements could not be consented. The formative evaluation detected a tendency towards a positive attitude for a digital training format and a very positive evaluation of the contents. DISCUSSION: Overall, important recommendations for a patient school can be drawn from this study. The following subjects require further investigation: format, inclusion criteria, group composition and inclusion of caregivers.

SAFE-ROCK: A Phase I Trial of an Oral Application of the ROCK Inhibitor Fasudil to Assess Bioavailability, Safety, and Tolerability in Healthy Participants.

BACKGROUND: The intravenous (IV) formulation of Rho-kinase (ROCK) inhibitor fasudil has been approved for the treatment of subarachnoid haemorrhage since 1995. Additionally, fasudil has shown promising preclinical results for various chronic diseases, including neurodegenerative diseases such as amyotrophic lateral sclerosis, Parkinson's disease, and dementia, in which long-term intravenous (IV) administration might not be suitable. OBJECTIVE: The objective of this study was to assess the absolute bioavailability of oral, in comparison to IV, application of the approved formulation of fasudil (ERIL®) and to evaluate the safety and tolerability of the oral application of fasudil. METHODS: This was a phase I, single-center, open-label, randomized, two period cross-over clinical trial in healthy women and men. By applying a cross-over design, each subject served as their own control. Two treatments were investigated, separated by a wash out phase of at least 3 days. Oral fasudil was administered once on day 1 to assess pharmacokinetics and three times on day 2, at an interval of 8 ± 1 h, to assess safety and gastrointestinal tolerability. For pharmacometrics of IV fasudil, it was administered once on day 1. Plasma profiles of fasudil and its active metabolite hydroxyfasudil after oral or IV administration were measured by liquid chromatography electrospray tandem mass spectrometry. Tolerability was assessed as proportion of subjects without significant drug intolerance, and safety was assessed by the proportion of subjects without clinical or laboratory treatment-associated serious adverse events. Gastrointestinal safety was assessed by applying the gastrointestinal symptom rating scale (GSRS). RESULTS: Fourteen subjects aged 30-70 years were included in this trial. After oral administration, fasudil concentrations in blood were mostly very low [1.4 g/L; coefficient of variation (CV) 41.0%]. After IV application, the peak concentration was 100.6 µg/L (CV 74.2%); however, a high variance in peak concentrations were assessed for both treatments. The maximal concentrations of hydroxyfasudil in blood were similar after oral and IV treatment [111.6 µg/L (CV 24.1%) and 108.4 µg/L (CV 19.7%), respectively]. Exposure of hydroxyfasudil (assessed as AUC0-tz) differed between both treatments, with 449 µg × h/L after IV treatment and 309 µg × h/L after oral treatment. Therefore, the absolute bioavailability of hydroxyfasudil after the oral treatment was approximately 69% of the IV treatment. No serious adverse events (SAEs) occurred during this trial, and good tolerability of oral fasudil (90 mg/day) was documented. CONCLUSIONS: Oral fasudil was generally well tolerated in the studied population, and no safety concerns were identified. However, systemic bioavailability of oral hydroxyfasudil corresponded to 69%, and dose adjustments need to considered. The results presented here lay grounds for future trials of fasudil in chronic diseases, which require an oral long-term application. This trial was registered with EudraCT (no. 2019-001805-26).

Glypican-4 serum levels are associated with cognitive dysfunction and vascular risk factors in Parkinson's disease.

Glypicans are biomarkers for various pathologies, including cardiovascular disease, cancer and diabetes. Increasing evidence suggests that glypicans also play a role in the context of neurodegenerative disorders. Initially described as supporting functionality of synapses via glutamate receptors during CNS development, Glypican 4 (GPC-4) also plays a role in the context of dementia via tau hyperphosphorylation in Alzheimer's disease, which is also a co-pathology in Parkinson's disease dementia. However, clinical evidence of circulating GPC-4 in Parkinson's disease (PD) is missing so far. We therefore investigated GPC-4 in biofluids of PD patients. We analyzed GPC-4 levels in cerebrospinal fluid (CSF, n = 140), serum (n = 80), and tear fluid samples (n = 70) of PD patients and control subjects in a similar age range by ELISA (serum, CSF) and western blot (tear fluid). Expression of circulating GPC-4 was confirmed in all three biofluids, with highest levels in serum. Interestingly, GPC-4 levels were age-dependent, and multiple regression analysis revealed a significant association between GPC-4 serum levels and MoCA score, suggesting an involvement of GPC-4 in PD-associated cognitive decline. Furthermore, stratification of PD patients for vascular risk factors revealed a significant increase of GPC-4 serum levels in PD patients with vascular risk factors. Our results suggest GPC-4 as a clinical biomarker for vascular risk stratification in order to identify PD patients with increased risk of developing dementia.

Protocol for a randomized, placebo-controlled, double-blind phase IIa study of the safety, tolerability, and symptomatic efficacy of the ROCK-inhibitor Fasudil in patients with Parkinson's disease (ROCK-PD).

Background: The Rho-kinase (ROCK) inhibitor Fasudil has shown symptomatic and disease-modifying effects in Parkinson's disease (PD) models in vitro and in vivo. In Japan, Fasudil has been approved for the treatment of subarachnoid haemorrhage since 1995 and shows a favourable safety profile. Objectives/design: To investigate the safety, tolerability, and symptomatic efficacy of ROCK-inhibitor Fasudil in comparison to placebo in a randomized, national, multicenter, double-blind phase IIa study in patients with PD. Methods/analysis: We plan to include 75 patients with at least 'probable' PD (MDS criteria), Hoehn and Yahr stages 1-3, and age 30-80 years in 13 German study sites. Patients must be non-fluctuating and their response to PD medication must have been stable for 6 weeks. Patients will be randomly allocated to treatment with the oral investigational medicinal product (IMP) containing either Fasudil in two dosages, or placebo, for a total of 22 days. As primary analysis, non-inferiority of low/high dose of Fasudil on the combined endpoint consisting of occurrence of intolerance and/or treatment-related serious adverse events (SAEs) over 22 days will be assessed in a sequential order, starting with the lower dose. Secondary endpoints will include tolerability alone over 22 days and occurrence of treatment-related SAEs (SARs) over 22 and 50 days and will be compared on group level. Additional secondary endpoints include efficacy on motor and non-motor symptoms, measured on established scales, and will be assessed at several timepoints. Biomaterial will be collected to determine pharmacokinetics of Fasudil and its active metabolite, and to evaluate biomarkers of neurodegeneration. Ethics/registration/discussion: After positive evaluation by the competent authority and the ethics committee, patient recruitment started in the 3rd quarter of 2023. ROCK-PD is registered with Eudra-CT (2021-003879-34) and clinicaltrials.gov (NCT05931575). Results of this trial can pave way for conducting extended-duration studies assessing both symptomatic efficacy and disease-modifying properties of Fasudil.

Long-term efficacy and safety of nusinersen in adults with 5q spinal muscular atrophy: a prospective European multinational observational study.

Background: Evidence for the efficacy of nusinersen in adults with 5q-associated spinal muscular atrophy (SMA) has been demonstrated up to a period of 16 months in relatively large cohorts but whereas patients reach a plateau over time is still to be demonstrated. We investigated the efficacy and safety of nusinersen in adults with SMA over 38 months, the longest time period to date in a large cohort of patients from multiple clinical sites. Methods: Our prospective, observational study included adult patients with SMA from Germany, Switzerland, and Austria (July 2017 to May 2022). All participants had genetically-confirmed, 5q-associated SMA and were treated with nusinersen according to the label. The total Hammersmith Functional Motor Scale Expanded (HFMSE) and Revised Upper Limb Module (RULM) scores, and 6-min walk test (6 MWT; metres), were recorded at baseline and 14, 26, and 38 months after treatment initiation, and pre and post values were compared. Adverse events were also recorded. Findings: Overall, 389 patients were screened for eligibility and 237 were included. There were significant increases in all outcome measures compared with baseline, including mean HFMSE scores at 14 months (mean difference 1.72 [95% CI 1.19-2.25]), 26 months (1.20 [95% CI 0.48-1.91]), and 38 months (1.52 [95% CI 0.74-2.30]); mean RULM scores at 14 months (mean difference 0.75 [95% CI 0.43-1.07]), 26 months (mean difference 0.65 [95% CI 0.27-1.03]), and 38 months (mean difference 0.72 [95% CI 0.25-1.18]), and 6 MWT at 14 months (mean difference 30.86 m [95% CI 18.34-43.38]), 26 months (mean difference 29.26 m [95% CI 14.87-43.65]), and 38 months (mean difference 32.20 m [95% CI 10.32-54.09]). No new safety signals were identified. Interpretation: Our prospective, observational, long-term (38 months) data provides further real-world evidence for the continuous efficacy and safety of nusinersen in a large proportion of adult patients with SMA. Funding: Financial support for the registry from Biogen, Novartis and Roche.

Metal dyshomeostasis in the substantia nigra of patients with Parkinson's disease or multiple sclerosis.

Abnormal metal distribution in vulnerable brain regions is involved in the pathogenesis of most neurodegenerative diseases, suggesting common molecular mechanisms of metal dyshomeostasis. This study aimed to compare the intra- and extra-neuronal metal content and the expression of proteins related to metal homeostasis in the substantia nigra (SN) from patients with Parkinson's disease (PD), multiple sclerosis (MS), and control subjects. Metal quantification was performed via ion-beam micro-analysis in neuromelanin-positive neurons and the surrounding tissue. For proteomic analysis, SN tissue lysates were analyzed on a nanoflow chromatography system hyphenated to a hybrid triple-quadrupole time-of-flight mass spectrometer. We found increased amounts of iron in neuromelanin-positive neurons and surrounding tissue in patients with PD and MS compared to controls (4- to 5-fold higher) that, however, also showed large inter-individual variations. Copper content was systematically lower (-2.4-fold) in neuromelanin-positive neurons of PD patients compared with controls, whereas it remained unchanged in MS. Protein-protein interaction (PPI) network analyses revealed clusters related to Fe and Cu homeostasis among PD-deregulated proteins. An enrichment for the term "metal homeostasis" was observed for MS-deregulated proteins. Important deregulated hub proteins included hemopexin and transferrin in PD, and calreticulin and ferredoxin reductase in MS. Our findings show that PD and MS share commonalities in terms of iron accumulation in the SN. Concomitant proteomics experiments revealed PPI networks related to metal homeostasis, substantiating the results of metal quantification.

Reduced tear fluid production in neurological diseases: a cohort study in 708 patients.

BACKGROUND: Tear fluid (TF) production is an important component of normal ocular function. It is regulated by parasympathetic and sympathetic innervation. Because parasympathetic nerve fibers originate in the brainstem, pathology in this brain region may affect TF production. For example, a reduction in TF production has been described in patients with Parkinson's disease (PD). METHODS: TF was collected at one center from 772 individuals, 708 of which were patients with different neurological diseases, and 64 healthy controls. Wetting lengths (WL) were recorded using Schirmer test strips with a collection time of 10 min. RESULTS: WL correlated negatively with age and was significantly reduced in subgroups of patients with neurodegenerative diseases (NDDs) (PD, Amyotrophic lateral sclerosis (ALS), other motor neuron diseases (MNDs)), as well as inflammatory/autoimmune/infectious central nervous system (CNS) diseases and vascular CNS diseases (VCDs), even if corrected for age or sex. While temperature had a significant negative effect on TF production, other environmental factors, such as hours of sunlight and humidity, did not. CONCLUSION: WL was altered in many neurological diseases compared to healthy controls. Most importantly, we observed a reduction of WL in NDDs, independent of age or sex. This study highlights the potential of WL as an easily obtainable parameter and suggests functional alterations in the autonomic innervation in various neurological disorders.

msqrob2PTM: Differential Abundance and Differential Usage Analysis of MS-Based Proteomics Data at the Posttranslational Modification and Peptidoform Level.

In the era of open-modification search engines, more posttranslational modifications than ever can be detected by LC-MS/MS-based proteomics. This development can switch proteomics research into a higher gear, as PTMs are key in many cellular pathways important in cell proliferation, migration, metastasis, and aging. However, despite these advances in modification identification, statistical methods for PTM-level quantification and differential analysis have yet to catch up. This absence can partly be explained by statistical challenges inherent to the data, such as the confounding of PTM intensities with its parent protein abundance. Therefore, we have developed msqrob2PTM, a new workflow in the msqrob2 universe capable of differential abundance analysis at the PTM and at the peptidoform level. The latter is important for validating PTMs found as significantly differential. Indeed, as our method can deal with multiple PTMs per peptidoform, there is a possibility that significant PTMs stem from one significant peptidoform carrying another PTM, hinting that it might be the other PTM driving the perceived differential abundance. Our workflows can flag both differential peptidoform abundance (DPA) and differential peptidoform usage (DPU). This enables a distinction between direct assessment of differential abundance of peptidoforms (DPA) and differences in the relative usage of peptidoforms corrected for corresponding protein abundances (DPU). For DPA, we directly model the log2-transformed peptidoform intensities, while for DPU, we correct for parent protein abundance by an intermediate normalization step which calculates the log2-ratio of the peptidoform intensities to their summarized parent protein intensities. We demonstrated the utility and performance of msqrob2PTM by applying it to datasets with known ground truth, as well as to biological PTM-rich datasets. Our results show that msqrob2PTM is on par with, or surpassing the performance of, the current state-of-the-art methods. Moreover, msqrob2PTM is currently unique in providing output at the peptidoform level.

Nationwide Retrospective Analysis of Combinations of Advanced Therapies in Patients With Parkinson Disease.

BACKGROUND AND OBJECTIVES: Advanced therapies (ATs; deep brain stimulation [DBS] or pump therapies: continuous subcutaneous apomorphine infusion [CSAI], levodopa/carbidopa intestinal gel [LCIG]) are used in later stages of Parkinson disease (PD). However, decreasing efficacy over time and/or side effects may require an AT change or combination in individual patients. Current knowledge about changing or combining ATs is limited to mostly retrospective and small-scale studies. The nationwide case collection Combinations of Advanced Therapies in PD assessed simultaneous or sequential AT combinations in Germany since 2005 to analyze their clinical outcome, their side effects, and the reasons for AT modifications. METHODS: Data were acquired retrospectively by modular questionnaires in 22 PD centers throughout Germany based on clinical records and comprised general information about the centers/patients, clinical (Mini-Mental Status Test/Montréal Cognitive Assessment, Movement Disorder Society-Sponsored Revision of the Unified Parkinson's Disease Rating Scale [MDS-UPDRS], side effects, reasons for AT modification), and therapeutical (ATs with specifications, oral medication) data. Data assessment started with initiation of the second AT. RESULTS: A total of 148 AT modifications in 116 patients were associated with significantly improved objective (median decrease of MDS-UPDRS Part III 4.0 points [p < 0.001], of MDS-UPDRS Part IV 6.0 points [p < 0.001], of MDS-UPDRS Part IV-off-time item 1.0 points [p < 0.001]) and subjective clinical outcome and decreasing side effect rates. Main reasons for an AT modification were insufficient symptom control and side effects of the previous therapy. Subgroup analyses suggest addition of DBS in AT patients with leading dyskinesia, addition of LCIG for leading other cardinal motor symptoms, and addition of LCIG or CSAI for dominant off-time. The most long-lasting therapy-until requiring a modification-was DBS. DISCUSSION: Changing or combining ATs may be beneficial when 1 AT is insufficient in efficacy or side effects. The outcome of an AT combination is comparable with the clinical benefit by introducing the first AT. The added AT should be chosen dependent on dominant clinical symptoms and adverse effects. Furthermore, prospective trials are needed to confirm the results of this exploratory case collection. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that, in patients with PD, changing or combining ATs is associated with an improvement in the MDS-UPDRS or subjective symptom reporting.

Loss of the parkinsonism-associated protein FBXO7 in glutamatergic forebrain neurons in mice leads to abnormal motor behavior and synaptic defects.

Mutations in PARK15, which encodes for the F-box protein FBXO7 have been associated with Parkinsonian Pyramidal syndrome, a rare and complex movement disorder with Parkinsonian symptoms, pyramidal tract signs and juvenile onset. Our previous study showed that systemic loss of Fbxo7 in mice causes motor defects and premature death. We have also demonstrated that FBXO7 has a crucial role in neurons as the specific deletion in tyrosine hydroxylase-positive or glutamatergic forebrain neurons leads to late-onset or early-onset motor dysfunction, respectively. In this study, we examined NEX-Cre;Fbxo7fl/fl mice, in which Fbxo7 was specifically deleted in glutamatergic projection neurons. The effects of FBXO7 deficiency on striatal integrity were investigated with HPLC and histological analyses. NEX-Cre;Fbxo7fl/fl mice revealed an increase in striatal dopamine concentrations, changes in the glutamatergic, GABAergic and dopaminergic pathways, astrogliosis and microgliosis and little or no neuronal loss in the striatum. To determine the effects on the integrity of the synapse, we purified synaptic membranes, subjected them to quantitative mass spectrometry analysis and found alterations in the complement system, endocytosis and exocytosis pathways. These neuropathological changes coincide with alterations in spontaneous home cage behavior. Taken together, our findings suggest that FBXO7 is crucial for corticostriatal projections and the synaptic integrity of the striatum, and consequently for proper motor control.

Proteomic analysis of the human hippocampus identifies neuronal pentraxin 1 (NPTX1) as synapto-axonal target in late-stage Parkinson's disease.

Parkinson's disease (PD) affects a significant proportion of the population over the age of 60 years, and its prevalence is increasing. While symptomatic treatment is available for motor symptoms of PD, non-motor complications such as dementia result in diminished life quality for patients and are far more difficult to treat. In this study, we analyzed PD-associated alterations in the hippocampus of PD patients, since this brain region is strongly affected by PD dementia. We focused on synapses, analyzing the proteome of post-mortal hippocampal tissue from 16 PD cases and 14 control subjects by mass spectrometry. Whole tissue lysates and synaptosomal fractions were analyzed in parallel. Differential analysis combined with bioinformatic network analyses identified neuronal pentraxin 1 (NPTX1) to be significantly dysregulated in PD and interacting with proteins of the synaptic compartment. Modulation of NPTX1 protein levels in primary hippocampal neuron cultures validated its role in synapse morphology. Our analysis suggests that NPTX1 contributes to synaptic pathology in late-stage PD and represents a putative target for novel therapeutic strategies.

Alpha-synuclein fibrils amplified from multiple system atrophy and Parkinson's disease patient brain spread after intracerebral injection into mouse brain.

Parkinson's disease (PD), multiple system atrophy (MSA), and dementia with Lewy bodies (DLB) are neurodegenerative disorders with alpha-synuclein (α-syn) aggregation pathology. Different strains of α-syn with unique properties are suggested to cause distinct clinical and pathological manifestations resulting in PD, MSA, or DLB. To study individual α-syn spreading patterns, we injected α-syn fibrils amplified from brain homogenates of two MSA patients and two PD patients into the brains of C57BI6/J mice. Antibody staining against pS129-α-syn showed that α-syn fibrils amplified from the brain homogenates of the four different patients caused different levels of α-syn spreading. The strongest α-syn pathology was triggered by α-syn fibrils of one of the two MSA patients, followed by comparable pS129-α-syn induction by the second MSA and one PD patient material. Histological analysis using an antibody against Iba1 further showed that the formation of pS129-α-syn is associated with increased microglia activation. In contrast, no differences in dopaminergic neuron numbers or co-localization of α-syn in oligodendrocytes were observed between the different groups. Our data support the spreading of α-syn pathology in MSA, while at the same time pointing to spreading heterogeneity between different patients potentially driven by individual patient immanent factors.

Guideline "Motor neuron diseases" of the German Society of Neurology (Deutsche Gesellschaft für Neurologie).

INTRODUCTION: In 2021, the Deutsche Gesellschaft für Neurology published a new guideline on diagnosis and therapy of motor neuron disorders. Motor neuron disorders affect upper motor neurons in the primary motor cortex and/or lower motor neurons in the brain stem and spinal cord. The most frequent motor neuron disease amyotrophic lateral sclerosis (ALS) is a rapidly progressive disease with an average life expectancy of 2-4 years with a yearly incidence of 3.1/100,000 in Central Europe (Rosenbohm et al. in J Neurol 264(4):749-757, 2017. https://doi.org/10.1007/s00415-017-8413-3 ). It is considered a rare disease mainly due to its low prevalence as a consequence of short disease duration. RECOMMENDATIONS: These guidelines comprise recommendations regarding differential diagnosis, neuroprotective therapies and multidisciplinary palliative care including management of respiration and nutrition as well as provision of assistive devices and end-of-life situations. CONCLUSION: Diagnostic and therapeutic guidelines are necessary due the comparatively high number of cases and the aggressive disease course. Given the low prevalence and the severe impairment of patients, it is often impossible to generate evidence-based data so that ALS guidelines are partially dependent on expert opinion.

Economic evaluation of Motor Neuron Diseases: a nationwide cross-sectional analysis in Germany.

BACKGROUND AND OBJECTIVES: Motor Neuron Diseases (MND) are rare diseases but have a high impact on affected individuals and society. This study aims to perform an economic evaluation of MND in Germany. METHODS: Primary patient-reported data were collected including individual impairment, the use of medical and non-medical resources, and self-rated Health-Related Quality of Life (HRQoL). Annual socio-economic costs per year as well as Quality-Adjusted Life Years (QALYs) were calculated. RESULTS: 404 patients with a diagnosis of Amyotrophic Lateral Sclerosis (ALS), Spinal Muscular Atrophy (SMA) or Hereditary Spastic Paraplegia (HSP) were enrolled. Total annual costs per patient were estimated at 83,060€ in ALS, 206,856€ in SMA and 27,074€ in HSP. The main cost drivers were informal care (all MND) and disease-modifying treatments (SMA). Self-reported HRQoL was best in patients with HSP (mean EuroQoL Five Dimension Five Level (EQ-5D-5L) index value 0.67) and lowest in SMA patients (mean EQ-5D-5L index value 0.39). QALYs for patients with ALS were estimated to be 1.89 QALYs, 23.08 for patients with HSP and 14.97 for patients with SMA, respectively. Cost-utilities were estimated as follows: 138,960€/QALY for ALS, 525,033€/QALY for SMA, and 49,573€/QALY for HSP. The main predictors of the high cost of illness and low HRQoL were disease progression and loss of individual autonomy. CONCLUSION: As loss of individual autonomy was the main cost predictor, therapeutic and supportive measures to maintain this autonomy may contribute to reducing high personal burden and also long-term costs, e.g., care dependency and absenteeism from work.

Parkinson's disease therapy: what lies ahead?

The worldwide prevalence of Parkinson's disease (PD) has been constantly increasing in the last decades. With rising life expectancy, a longer disease duration in PD patients is observed, further increasing the need and socioeconomic importance of adequate PD treatment. Today, PD is exclusively treated symptomatically, mainly by dopaminergic stimulation, while efforts to modify disease progression could not yet be translated to the clinics. New formulations of approved drugs and treatment options of motor fluctuations in advanced stages accompanied by telehealth monitoring have improved PD patients care. In addition, continuous improvement in the understanding of PD disease mechanisms resulted in the identification of new pharmacological targets. Applying novel trial designs, targeting of pre-symptomatic disease stages, and the acknowledgment of PD heterogeneity raise hopes to overcome past failures in the development of drugs for disease modification. In this review, we address these recent developments and venture a glimpse into the future of PD therapy in the years to come.

The heterogeneity of Parkinson's disease.

The heterogeneity of Parkinson's disease (PD), i.e. the various clinical phenotypes, pathological findings, genetic predispositions and probably also the various implicated pathophysiological pathways pose a major challenge for future research projects and therapeutic trail design. We outline several pathophysiological concepts, pathways and mechanisms, including the presumed roles of α-synuclein misfolding and aggregation, Lewy bodies, oxidative stress, iron and melanin, deficient autophagy processes, insulin and incretin signaling, T-cell autoimmunity, the gut-brain axis and the evidence that microbial (viral) agents may induce molecular hallmarks of neurodegeneration. The hypothesis is discussed, whether PD might indeed be triggered by exogenous (infectious) agents in susceptible individuals upon entry via the olfactory bulb (brain first) or the gut (body-first), which would support the idea that disease mechanisms may change over time. The unresolved heterogeneity of PD may have contributed to the failure of past clinical trials, which attempted to slow the course of PD. We thus conclude that PD patients need personalized therapeutic approaches tailored to specific phenomenological and etiologic subtypes of disease.

Addressing uncertainties in correlative imaging of exogenous particles with the tissue microanatomy with synchronous imaging strategies.

Exposure to exogenous particles is of increasing concern to human health. Characterizing the concentrations, chemical species, distribution, and involvement of the stimulus with the tissue microanatomy is essential in understanding the associated biological response. However, no single imaging technique can interrogate all these features at once, which confounds and limits correlative analyses. Developments of synchronous imaging strategies, allowing multiple features to be identified simultaneously, are essential to assess spatial relationships between these key features with greater confidence. Here, we present data to first highlight complications of correlative analysis between the tissue microanatomy and elemental composition associated with imaging serial tissue sections. This is achieved by assessing both the cellular and elemental distributions in three-dimensional space using optical microscopy on serial sections and confocal X-ray fluorescence spectroscopy on bulk samples, respectively. We propose a new imaging strategy using lanthanide-tagged antibodies with X-ray fluorescence spectroscopy. Using simulations, a series of lanthanide tags were identified as candidate labels for scenarios where tissue sections are imaged. The feasibility and value of the proposed approach are shown where an exposure of Ti was identified concurrently with CD45 positive cells at sub-cellular resolutions. Significant heterogeneity in the distribution of exogenous particles and cells can be present between immediately adjacent serial sections showing a clear need of synchronous imaging methods. The proposed approach enables elemental compositions to be correlated with the tissue microanatomy in a highly multiplexed and non-destructive manner at high spatial resolutions with the opportunity for subsequent guided analysis.

Long-Lasting Impact of the COVID-19 Pandemic on Patients with Parkinson's Disease and Their Relatives.

Background: The coronavirus disease 2019 (COVID-19) pandemic has heavily impacted medical care of patients with Parkinson's disease (PwP). Objective: To assess the longitudinal impact of the COVID-19 pandemic on PwP and their relatives in Germany. Methods: Two online, nationwide, cross-sectional surveys were conducted from December 2020 to March 2021 and from July to September 2021. Results: A total of 342 PwP and 113 relatives participated. Despite partial resumption of social and group activities, healthcare was continuously disrupted during times of loosened restrictions. Respondents' willingness to use telehealth infrastructure increased, yet the availability remained low. PwP reported worsened symptoms and further deterioration during the pandemic, resulting in an increase in new symptoms and relatives' burden. We identified patients at particular risk: young patients and those with long disease duration. Conclusions: The COVID-19 pandemic persistently disrupts the care and quality of life of PwP. Although willingness to use telemedicine services has increased, its availability needs to be improved.