Alzheimer & Parkinson

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Increased life expectancy brought about by improved healthcare and lifestyle has heightened the challenge of neurodegenerative disorders like Alzheimer's disease (AD) and other age-related disorders. Neurodegeneration is known to be accompanied by loss of memory, changes in brain morphology, and neuroinflammation, and multiple factors contribute to the progression and pathogenesis of the condition. Of these factors, metabolic dysregulation is known to influence the process, but the precise...

Processing bodies (P-bodies) are conserved ribonucleoprotein granules central to RNA metabolism across eukaryotes. Although the mechanisms underlying their assembly are well understood, the pathways governing their selective turnover remain unclear. Here, we identify the conserved decapping proteins Enhancer of mRNA decapping 4 (EDC4) and decapping protein 1 (DCP1) as a selective autophagy receptor pair responsible for P-body turnover in the model plant Marchantia polymorpha. MpEDC4 engages ATG8...

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The brain continuously integrates rapidly changing visual input across eye movements to maintain stable perception, yet the precise mechanisms underpinning dynamic working memory and how these break down in brain diseases remain unclear. We developed a novel eye-tracking paradigm and computational models to investigate how spatial and colour information are updated across saccades in the human brain. Our findings reveal that saccades selectively impair spatial but not colour memory....

Synaptic Plasticity pertains to the synapse's tendency to adapt fresh information and is a crucial step in the establishment of brain circuits that aid in memory formation. It has become one of the most intensively researched topics in all of neuroscience. Pieces of evidence are accumulating that synaptopathy (altered synaptic plasticity) mechanisms contribute to Alzheimer's disease (AD) and Parkinson's disease (PD). Toxins responsible for synaptopathy and aberrant neurotransmitter (NT) release...

This review synthesizes three decades of evidence regarding the role of cytochrome P450 enzymes (CYPs) in Parkinson's disease (PD), revealing their multifaceted roles beyond traditional pesticide metabolism. While CYP2D6 remains the most studied enzyme due to its association with PD risk in poor metabolizer phenotypes and its dual role in dopamine (DA) synthesis (directly via tyramine hydroxylation and indirectly through precursor demethylation), recent research has highlighted less-studied CYPs...

Normative models are increasingly used to characterize individual-level brain deviations in neuroimaging studies, but their performance depends heavily on the reference sample used for training or adaptation. In this study, we systematically investigated how sample size and covariate composition of the reference cohort influence model fit, deviation estimates, and clinical readouts in Alzheimer's disease (AD). Using a discovery dataset (OASIS-3, n = 1032), we trained models on healthy control...

With the introduction of adaptive deep brain stimulation (aDBS) for Parkinson's disease, new questions emerge regarding who, why, and how to treat. This paper outlines the pathophysiological rationale for aDBS, which provides real-time modulation of the stimulation amplitude based on subthalamic beta (range 13-30 Hz) activity and related physiomarkers. We review clinical evidence comparing aDBS with conventional DBS in terms of motor improvement, side-effect reduction, energy efficiency, and...

Early intervention is the most effective strategy to impede the progression of Alzheimer's disease (AD), depending on the identification of early diagnostic biomarkers. Here, we isolate neuron-derived exosomes (NDEs) from plasma of familial AD (FAD), presymptomatic FAD (pre-FAD), and healthy controls (cognitively normal [CN]), followed by label-free liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. A specific peptide from protein phosphatase 2 regulatory subunit B'β (PPP2R5C)...

Dysfunction of transactive response DNA-binding protein 43 (TDP-43) drives neurodegeneration in amyotrophic lateral sclerosis (ALS) and Alzheimer's disease (AD), in part through inducing aberrant RNA splicing. However, whether such mis-splicing yields stable, pathogenic proteins remains unclear. Here, we identify a TDP-43-repressed cryptic exon in Protein kinase N1 (PKN1), designated PKN1-5a1, which is activated in ALS patient brains and introduces a premature termination codon. This aberrant...

The APOE-ε4 allele is the strongest genetic risk factor for late-onset Alzheimer's disease. However, APOE-ε4 is not deterministic, highlighting the need to identify additional genetic and environmental factors. APOE-ε4 has been linked to accelerated cognitive decline, so we sought to investigate genetic factors that modify APOE-ε4-associated cognitive decline. We conduct cross-ancestry APOE-ε4-stratified and interaction GWAS using harmonized cognitive data from 32,778 participants, including...

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The nonreceptor Abelson (Abl) tyrosine kinases have been implicated as key drivers of initiation and progression in Parkinson's disease (PD). Risvodetinib, a potent, brain-penetrant, selective inhibitor of the nonreceptor Abl kinases c-Abl1 and c-Abl2/Arg (collectively, c-Abl), was evaluated in a randomized, double-blind, placebo-controlled phase 2a trial ('the 201 Trial') using once-daily 50 mg, 100 mg, 200 mg or placebo in 137 participants with early, untreated PD. The primary end points in...

Tauopathies are neurodegenerative diseases marked by pathological tau aggregation. While disease-specific folds of insoluble tau filaments have been established, it remains unclear whether the smaller, earlier species also differ across tauopathies. Here, we characterize these small tau aggregates from postmortem brain of individuals with Alzheimer's disease (AD), progressive supranuclear palsy (PSP), corticobasal degeneration, Pick's disease, and healthy controls. Using two complementary...

CONCLUSIONS: The strength and significance of our study are that it is the first to indicate, on the basis of the α-syn mechanism, that the mean RNFL thickness partly reflects striatal dopamine uptake in the brain, suggesting that the mean RNFL thickness may have a certain value for the early diagnosis of PD.

Blood factors transfer the benefits of exercise to the aged brain independent of physical activity. Here, we show that the liver-derived exercise factor (exerkine) glycosylphosphatidylinositol (GPI)-specific phospholipase D1 (GPLD1), a GPI-degrading enzyme, reverses aging- and Alzheimer's-related memory loss by targeting the brain vasculature. GPLD1 has the potential to cleave over 100 putative GPI-anchored proteins, necessitating the identification of downstream targets that mediate cognitive...

Insulating sheaths of myelin accelerate neuronal communication in the mammalian brain. Oligodendrocytes that produce myelin are generated throughout life to gradually increase myelin coverage, but these dynamics have not been defined brain-wide across the lifespan. We developed a cellular mapping pipeline involving tissue clearing, lightsheet microscopy, and AI-assisted analysis to identify the precise location of millions of oligodendrocytes and assess regional myelin density in the mouse...

Interference from distracting stimuli renders short-term memory vulnerable. While behavioral evidence suggests short-term memory deficits in Alzheimer's disease (AD), the underlying neural mechanisms remain poorly understood. Using a mouse model of AD (APP-KI), we identified increased susceptibility of short-term memory to sensory perturbations. Simultaneous two-photon calcium imaging across eight cortical regions during a delayed-response task showed that distractors disrupted neural...

Alzheimer's disease (AD) is an irreversible neurodegenerative disorder whose progression is closely associated with time. However, most diagnostic models are based on single time-point data, overlooking longitudinal disease characteristics. Structural magnetic resonance imaging (sMRI) has been widely utilized in the study of AD. To address the need for multi-time series analysis in longitudinal AD research and the integration of features from different brain tissues, we propose a Multi-Branch...