Single-nucleus transcriptomics reveals disease- and pathology-specific signatures in α-synucleinopathies.

α-synucleinopathies are progressive neurodegenerative disorders characterized by intracellular aggregation of α-synuclein, yet their molecular pathogenesis remains unknow. Here, we explore cell-specific changes in gene expression across different α-synucleinopathies. We perform single-nucleus RNA sequencing on nearly 300,000 nuclei from the prefrontal cortex of individuals with idiopathic Parkinson's disease (iPD, n = 20), Parkinson's disease caused by LRRK2 mutations (LRRK2-PD, n = 7), multiple system atrophy (MSA, n = 6) and healthy controls (n = 13).

Risk factors and evolution of weight loss in Parkinson's disease: A 9-year population-based study.

Introduction: Weight loss is considered a common complication of Parkinson's disease (PD), but there are few prospective longitudinal studies on weight loss in patients followed from time of PD diagnosis. We sought to determine the frequency, evolution and risk factors of weight loss in a representative incident PD cohort.

Methods: In this prospective population-based observational study, we followed 180 newly-diagnosed, initially drug-naïve PD patients and 161 controls with repetitive weight examinations over 9 years.

Amyotrophic lateral sclerosis caused by the expansion in Norway - prevalence, ancestry, clinical characteristics and sociodemographic status.

Objective: The most common genetic cause of amyotrophic lateral sclerosis (ALS) is the expansion. A high incidence of this expansion has been detected in Sweden and Finland. This Norwegian population-based study aimed to identify the prevalence, geographic distribution, ancestry, and relatedness of ALS patients with a expansion (C9).

Brain Proteome Profiling Reveals Common and Divergent Signatures in Parkinson's Disease, Multiple System Atrophy, and Progressive Supranuclear Palsy.

The molecular pathogenesis of degenerative parkinsonisms, including Parkinson's disease (PD), progressive supranuclear palsy (PSP), and Multiple system atrophy (MSA), remains largely unknown. To gain novel insight into molecular processes associated with these diseases, we conducted a proteome-wide expression study in prefrontal cortex tissue from a cohort of 181 individuals, comprising PD (N = 73), PSP (N = 18), MSA (N = 17) and healthy control (N = 73). Using marker gene profiles, we first assess the cellular composition of the samples and, subsequently, identify distinct protein signatures for each disease, while correcting for cell composition.

Serum neurofilament light at diagnosis: a prognostic indicator for accelerated disease progression in Parkinson's Disease.

Neurofilament light chain (NFL) is elevated in neurodegenerative diseases, including Parkinson's disease (PD). This study aimed to investigate serum NFL in newly diagnosed PD and its association with cognitive and motor decline over 10 years. Serum NFL levels were measured in PD patients and controls from the ParkWest study at diagnosis (baseline) and after 3 and 5 years.

Orthostatic Hypotension and Risk of Mild Cognitive Impairment and Dementia in Parkinson's Disease.

Background: Orthostatic hypotension (OH) is a common condition in Parkinson's disease (PD) with a possible link to cognitive decline.

Objective: The aim was to explore the association between OH and PD-associated mild cognitive impairment (PD-MCI) and dementia (PDD) over 9 years in a population-based incident PD cohort.

Methods: We prospectively followed up patients from PD diagnosis with serial blood pressure measurements, clinical examinations, and neuropsychological assessments.

Repeat expansions in , , and in Norwegian patients diagnosed with amyotrophic lateral sclerosis.

Genetic repeat expansions cause neuronal degeneration in amyotrophic lateral sclerosis as well as other neurodegenerative disorders such as spinocerebellar ataxia, Huntington's disease and Kennedy's disease. Repeat expansions in the same gene can cause multiple clinical phenotypes. We aimed to characterize repeat expansions in a Norwegian amyotrophic lateral sclerosis cohort.

European Academy of Neurology (EAN) guideline on the management of amyotrophic lateral sclerosis in collaboration with European Reference Network for Neuromuscular Diseases (ERN EURO-NMD).

Background: This update of the guideline on the management of amyotrophic lateral sclerosis (ALS) was commissioned by the European Academy of Neurology (EAN) and prepared in collaboration with the European Reference Network for Neuromuscular Diseases (ERN EURO-NMD) and the support of the European Network for the Cure ALS (ENCALS) and the European Organization for Professionals and Patients with ALS (EUpALS).

Methods: Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology was used to assess the effectiveness of interventions for ALS. Two systematic reviewers from Cochrane Response supported the guideline panel.

A prospective study for using cognitive decline as a predictor for survival and use of feeding/respiratory support for patients with motor neuron disease in Norway.

Background: There is a need for knowledge regarding the medical management of motor neuron disease/amyotrophic lateral sclerosis (MND/ALS) with and without cognitive decline. It has scarcely been studied whether cognitive decline will influence the course of disease or interfere with the use of life-prolonging aids for respiration and nutrition. Cognitive decline may impact the length of illness.

Cognitive Profile in Parkinson's Disease Dementia Patients with Low versus Normal Cerebrospinal Fluid Amyloid Beta.

Introduction: In patients with Parkinson's disease (PD), low cerebrospinal fluid (CSF) amyloid beta 1-42 (Ab42) at baseline is the most consistent CSF biomarker as a risk factor for developing dementia. Low CSF Ab42 is, however, a typical hallmark of Alzheimer's disease (AD). Hence, low CSF Ab42 in patients with PD may indicate presence of comorbid AD pathology and may predict a more AD-like cognitive profile when they develop dementia.

Genetic overlap between ALS and other neurodegenerative or neuromuscular disorders.

Objective: In Norway, 89% of patients with Amyotrophic lateral sclerosis (ALS) lacks a genetic diagnose. ALS genes and genes that cause other neuromuscular or neurodegenerative disorders extensively overlap. This population-based study examined whether patients with ALS have a family history of neurological disorders and explored the occurrence of rare genetic variants associated with other neurodegenerative or neuromuscular disorders.

Identification of diagnostic and prognostic biomarkers of PD using a multiplex proteomics approach.

Given the complexity of Parkinson's disease (PD), achieving acceptable diagnostic and prognostic accuracy will require the support of a panel of diverse biomarkers. We used Proximity extension assays to measure a panel of 92 proteins in CSF of 120 newly diagnosed PD patients and 45 control subjects without neurological disease. From 75 proteins detectable in the CSF of >90% of the subjects, regularized regression analysis identified four proteins (β-NGF, CD38, tau and NCAN) as downregulated in newly diagnosed PD patients (age at diagnosis 67.

Seed Amplification Assay as a Diagnostic Tool in Newly-Diagnosed Parkinson's Disease.

Seed amplification assays (SAA) are the first credible molecular assay for Parkinson's disease (PD). However, the value of SAA to support the clinicians' initial diagnosis of PD is not clear. In our study, we analyzed cerebrospinal fluid samples from 121 PD patients recruited through population screening methods and taken within a median delay of 38 days from diagnosis and 51 normal controls without neurodegenerative disease.

Cognitive and Motor Decline in Dementia with Lewy Bodies and Parkinson's Disease Dementia.

Background: There is a need to better understand the rate of cognitive and motor decline of Dementia with Lewy bodies (DLB) and Parkinson's disease Dementia (PDD).

Objectives: To compare the rate of cognitive and motor decline in patients with DLB and PDD from the E-DLB Consortium and the Parkinson's Incidence Cohorts Collaboration (PICC) Cohorts.

Methods: The annual change in MMSE and MDS-UPDRS part III was estimated using linear mixed regression models in patients with at least one follow-up (DLB  = 837 and PDD  = 157).

Inflammatory Biomarkers in Newly Diagnosed Patients With Parkinson Disease and Related Neurodegenerative Disorders.

Background And Objectives: Neuroinflammation contributes to Parkinson disease (PD) pathology, and inflammatory biomarkers may aid in PD diagnosis. Proximity extension assay (PEA) technology is a promising method for multiplex analysis of inflammatory markers. Neuroinflammation also plays a role in related neurodegenerative diseases, such as dementia with Lewy bodies (DLB) and Alzheimer disease (AD).

Treatment of motor symptoms in Parkinson's disease.

In recent years, the development of new therapies and improvements in our understanding of older therapies have led to changes in the management of Parkinson's disease. However, current Norwegian and international therapy recommendations present a range of different options as being equally viable. In this clinical review, we propose an updated algorithm for the medical treatment of motor symptoms in Parkinson's disease, based on evidence-based recommendations and our own personal experience and opinions.

Norwegian version of the Edinburgh cognitive and behavioural ALS screen: Construct validity, internal consistency, inter-rater, and test-retest reliability.

Background: Research collaboration highlight a need for validated tests in other languages than English. Translation and culture adjustments may threaten essential features of the original instrument.

Objective: To assess the internal consistency, inter-rater and test-retest reliability, and construct validity of the Norwegian version of the Edinburgh Cognitive and Behavioural Amyotrophic Lateral Sclerosis (ALS) Screen (ECAS-N).

Altered transcriptome-proteome coupling indicates aberrant proteostasis in Parkinson's disease.

Aberrant proteostasis is thought to be implicated in Parkinson's disease (PD), but patient-derived evidence is scant. We hypothesized that impaired proteostasis is reflected as altered transcriptome-proteome correlation in the PD brain. We integrated transcriptomic and proteomic data from prefrontal cortex of PD patients and young and aged controls to assess RNA-protein correlations across samples.

Association of CSF Glucocerebrosidase Activity With the Risk of Incident Dementia in Patients With Parkinson Disease.

Background And Objectives: Variations in the glucocerebrosidase gene () are common risk factors for Parkinson disease (PD) and dementia in PD (PDD) and cause a reduction in the activity of the lysosomal enzyme glucocerebrosidase (GCase). It is anticipated that GCase dysfunction might contribute to a more malignant disease course and predict cognitive impairment in PD, although evidence is lacking. We aimed to discover whether CSF GCase activity is altered in newly diagnosed patients with PD and associated with future development of dementia.