REM Sleep Behavior Disorder (iRBD)

The project aims to investigate how abnormal accumulation of alpha synuclein and its interaction with tau influence brain function across the Parkinson's disease (PD) spectrum, with particular focus on individuals carrying GBA1 mutations. This interventional, monocentric, cross sectional study includes patients with PD, individuals with idiopathic REM sleep behavior disorder, and participants without PD. All enrolled subjects will undergo clinical and neuropsychological assessments, blood based biomarker analyses related to neurodegeneration, synaptic and mitochondrial function, and multimodal brain MRI to evaluate brain structure, white matter integrity, and functional connectivity. The study aims to: * characterize the relationship between alpha synuclein/tau pathology and synaptic mitochondrial dysfunction; * identify biomarker and connectivity signatures across disease stages and genetic backgrounds; * integrate preclinical, clinical, biological, and imaging data to support the development of mechanistic models of alpha synuclein propagation. In parallel, preclinical studies in GBA PD mouse models and wild type mice will be used to investigate how changes in PD-related pathology (alpha-synuclein and tau) relates to behavior, brain imaging alterations and mitochondrial, axonal and synaptic damage. Animal model will also aid the validation of a new PET tracer that targets alpha synuclein (i.e., \[¹⁸F\]Syntacasyn). Together, human and preclinical studies are designed to provide a translational framework integrating molecular changes with brain network alterations and clinical heterogeneity in PD.

Parkinson's disease (PD) is the second most common neurodegenerative disorder after Alzheimer's disease, with over 12 million patients expected globally by 2040. The disease is currently diagnosed at the appearance of motor symptoms, but by then, over 60% of striatal dopaminergic neurons have already been destroyed. Prodromal symptoms such as idiopathic REM Sleep Behavior Disorder (iRBD), anosmia, mood disorders and constipation appear earlier and are listed as criteria for a prodromal PD diagnosis. Identifying early signs is critical to initiate neuroprotective treatments as early as possible. While pain is prevalent and highly disabling in early PD, no data are currently available on pain perception in iRBD patients, whose condition is of the main risk factor for PD development.

BioFINDER-Sleep study was established in 2021 and will include patients with early Parkinson´s disease (PD) and persons with iRBD to provide essential insights into the underlying mechanisms of the progressive neurodegenerative processes in central and peripheral nervous systems. Briefly polysomnography will be used to establish the presence of RBD in both the early PD cohort and in the iRBD cohort. Then, state of the art multimodal imaging techniques will be used, including, magnetic resonance imaging (MRI), positron emission tomography (PET) of the dopamine transporters (DAT-PET) to quantify dopamine terminal loss, and \[123I\] MIBG scintigraphy of the heart will be performed to quantify the loss noradrenaline terminals to the heart. In addition to this, synuclein seed amplification assays (SSAs) will be applied to cerebrospinal fluid (CSF) and skin samples to establish synuclein pathology status. Further, CSF and blood biomarkers will be developed that can be used to as prognostic markers. These investigations will be done in parallel to clinical assessments of motor and non-motor symptoms as well as assessment of cognitive function in a longitudinal setting.

The goal of this study is to use ultra-high-resolution (UHR) PET imaging to better understand how the brain and spinal cord change in healthy aging and in neurological and psychiatric disorders such as Alzheimer's disease (AD), Parkinson's disease and related movement disorders, amyotrophic lateral sclerosis (ALS), and psychotic disorders. Researchers will use the NeuroExplorer PET/CT system, a new scanner that can show very small structures in the brain and spinal cord in much more detail than regular PET. The main questions this study aims to answer are: * How do small but important brain regions (like the locus coeruleus, substantia nigra, and thalamic nuclei) change in healthy aging? * What early brain changes occur in neurodegenerative and psychotic disorders, and can they help improve early diagnosis? Participants will: * Undergo PET and MRI brain scans using different tracers that measure brain metabolism (18F-FDG), synaptic density (¹⁸F-SynVesT-1), dopamine transporters (¹⁸F-PE2I), and tau protein buildup (¹⁸F-MK6240). * Complete cognitive and clinical assessments related to memory, mood, and motor or psychiatric symptoms, depending on their group. This study will include healthy volunteers and patients with mild cognitive impairment due to Alzheimer´s disease, ALS, Parkinson's disease and related disorders, or psychotic disorders. The results will help create detailed brain imaging maps for healthy aging and identify early biomarkers for different diseases to support better diagnosis and treatment in the future.

Multicenter controlled study of sleep disorders in isolated REM Behavior Disorder and Parkinson\'s disease (SOMPARK)

This study tests whether enhancing deep sleep with gentle sounds at night can slow progression in people with iRBD or early Parkinson's disease. Participants wear a sensor headband and headphones for 18 months. Four assessments including mobility, memory, imaging (PET/MRI), lumbar puncture, and blood tests are assessed.

Parasomnias are unwanted events during sleep. These refer to sleep terrors, sleepwalking, sleep eating, nightmares, and movement during REM sleep. There are few systematic behavioral treatments for these problems and individuals with them often receive little education about self-management. This research examines and evaluates the effectiveness of a 4 week online course providing education and guidance about managing parasomnias. The primary outcomes are improvement in parasomnia frequency and distress. The secondary outcomes are improvements in work and social adjustment, mood, anxiety, stress level, fatigue, sleepiness, insomnia, and cognitive interference.

It is not known what causes Parkinson's disease and what makes it worsen over time. Research conducted in the past few years has highlighted the possible role of inflammation on this process but its actual mechanisms are still obscure. In this study, the investigators aim to gain understanding on how inflammation is increased in Parkinson's disease and what are its mechanisms, by performing two Positron Emission Tomography (PET) scans using the tracer \[11C\]PBR28, that takes pictures of the brain highlighting the areas of inflammation, before and after the administration of a compound called Lipopolysaccharide or LPS, that is known to cause a mild degree of inflammation. The investigators will couple this study with two venous blood draws to measure the levels of circulating molecules of inflammation.