Alzheimer & Parkinson

Wearing-off (WO) is a common motor complication in Parkinson's disease (PD), characterized by the re-emergence of symptoms before the next dose of dopaminergic medication and still lacking objective, bedside-available neurophysiological biomarkers. In this study, we investigated cortical functional network alterations associated with WO using resting-state functional near-infrared spectroscopy (fNIRS), graph-theoretical analysis, and machine learning. Resting-state fNIRS signals were acquired...

Age-related neurodegenerative diseases, including Alzheimer's disease (AD), Parkinson's disease (PD), and related dementias, are increasingly understood as multifactorial proteinopathies involving co-aggregation of amyloidogenic proteins such as Tubulin-associated unit protein (Tau), α-synuclein (α-syn), amyloid-β (Aβ), and TAR DNA-binding protein 43 (TDP-43). Rather than acting independently, these proteins often cross-seed, co-localize, and modulate each other's aggregation dynamics and...

No abstract

Aberrant activation of innate immune signaling is known to contribute to neuroinflammation in age-related neurological disorders, but the mechanisms underlying this activation remain unclear. Here, we discovered that protein S-nitrosylation, a redox-based posttranslational modification, regulates the stimulator of interferon genes (STING) protein in Alzheimer's disease (AD). Using a combination of redox chemical biology and mass spectrometry, we identified S-nitrosylation at cysteine 148 as a...

Nanoscopic aggregates of alpha-synuclein (ɑSyn) have been observed in Parkinson's disease (PD). However, the processes that occur in vivo leading to the formation of these small aggregates are not well understood. We used ultra-sensitive single-molecule methods, including single molecule array (SIMOA), and super-resolution microscopy to quantify and characterize ɑSyn aggregates harvested from human brain samples, alongside a mouse model of synucleinopathy, using different tissue processing...

Dysfunctional autophagy, a key cellular cleaning process, is a key driver of brain ageing and neurodegenerative diseases such as Alzheimer's disease (AD). However, developing effective treatments by enhancing autophagy has been challenging, as most known compounds act through the broad mTOR pathway, risking side effects, and few can effectively penetrate the brain. To address this, we developed DeepDrugDiscovery-a mechanism-aware, AI-powered screening platform incorporating ADMET and blood-brain...

The presence of neuromelanin is a characteristic feature of the human substantia nigra (SN); however, the mechanism of its synthesis and its role in the development of Parkinson's disease remain unclear. Here, we report that the host defense enzyme lactoperoxidase (LPO), which possesses broad antimicrobial activity on mucosal surfaces, is selectively expressed in human dopaminergic neurons, a feature not shared by the rodent SN. We also demonstrate that LPO can catalyze multiple steps of melanin...

The traditional pathological framework of Alzheimer's disease (AD) primarily focuses on the accumulation of β-amyloid (Aβ) and tau proteins. However, therapeutic strategies targeting these molecules have repeatedly encountered setbacks in clinical translation. Recent studies have progressively revealed that the dynamic interaction network among intracellular organelles plays a central role in the pathogenesis of AD. This systematic review examines the independent dysfunctions of three key...

The aberrant aggregation of tau leads to loss of its physiological functions and gain of toxic functions, and plays a crucial role in the pathogenesis of tauopathies including Alzheimer's disease (AD). Targeting tau aggregation is considered a promising strategy for treating tauopathies. The BRICHOS family consists of a variety of proteins containing the BRICHOS domain. Certain endogenous BRICHOS domains may inhibit the pathological aggregation of disease-associated proteins. However, the...

Amyloid beta (Aβ) plaque deposition in the central nervous system (CNS) is a hallmark of Alzheimer's disease (AD) and cerebral amyloid angiopathy (CAA), triggering robust innate immune responses. However, the role of the adaptive immune system remains less well understood. Here we show the immune microenvironment dynamics in APP23 transgenic (APP23-tg) mice modelling CNS amyloid pathology, using single-cell transcriptomics. We observed a marked increase in T-cell populations during late disease...

The entorhinal cortex is a critical brain area for memory formation, while also the region exhibiting the earliest histological and functional alterations in Alzheimer's disease (AD). The entorhinal cortex therefore has been long hypothesized as one of the originating brain areas of AD pathophysiology, although circuit mechanisms causing its selective vulnerability remain poorly understood. Here we show that dopamine neurons projecting their axons to the lateral entorhinal cortex (LEC), critical...

An in vivo approach combining high-throughput screening with cell type-specific readouts could enable elucidation of genotype-phenotype relationships in complex tissues. We developed an in vivo gain-of-function Perturb-seq platform, termed iGOF-Perturb-seq, to build a functional atlas of ~1000 transcription factors (TFs) in astrocytes, a cell type essential to many brain functions. We then identified cofunctional modules, annotated uncharacterized TFs, and predicted disease-associated TF...

Alzheimer's disease (AD) is a neurodegenerative condition characterized by microglia-mediated neuroinflammation. Deep (>1,000×) panel sequencing of 311 brain samples revealed enrichment of somatic single-nucleotide variants (sSNVs) in cancer driver genes in AD brains, especially in genes associated with clonal hematopoiesis (CH). These sSNVs were associated with clonal expansion and carried by both microglia-like brain macrophages (MLBMs) in multiple brain regions as well as paired blood,...

Alzheimer's disease (AD) and type 2 diabetes mellitus (T2DM) share metabolic and inflammatory mechanisms, potentially mediated by the gut microbiota, yet the neurobiological impact of comorbid AD+T2DM microbiota from elderly donors remains unexplored. Fecal microbiota from healthy, AD, T2DM, and AD+T2DM postmenopausal female donors (aged 56-89 years) was transplanted into antibiotic-treated male mice. Behavioral testing, blood profiling, hippocampal neurotrophic gene expression, and 16S rRNA...

We propose a computational framework for spatial niche analysis (SpaNiche) in spatial transcriptomics data to uncover colocalization patterns and infer potential ligand-receptor interactions. SpaNiche leverages graph-regularized joint non-negative matrix factorization to integrate information from cell abundance and ligand-receptor expression, identifying spatial colocalization patterns among cell types while providing insights into associated ligand-receptor interactions. Besides, SpaNiche...

Cerebrospinal fluid amyloid beta 42, total tau, and phosphorylated tau 181 are well accepted markers of Alzheimer's disease. These biomarkers better reflect disease pathogenesis compared to clinical diagnosis. Here, we perform a genome wide association study meta-analysis including 18,948 individuals of European ancestry and identify 12 genome-wide significant loci across all three biomarkers, eight of them novel. We replicate the association of biomarkers with APOE, CR1, GMNC/CCDC50 and...

Neuroinflammation plays a key role in Alzheimer's disease (AD) and many other neurodegenerative disorders. Chronic activation of astrocytes and microglia fuels neuronal damage via cytokine secretion, oxidative stress, and proteolysis, yet glial inflammatory regulation remains poorly understood. Using chemoproteomics, we identified CK2, particularly the brain-enriched catalytic subunit CK2α2, as a key driver of astrocytic inflammation. CK2 enhances NF-κB activity by phosphorylating NF-κB S529 and...

Diagnostic models using primary care routine clinical variables have been limited in their ability to identify Alzheimer's disease (AD) patients. In this study, we sought to better understand the effect of mild cognitive impairment (MCI) on the predictive performance of AD diagnostic models. We sourced data from the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort. CatBoost was used to assess the utility of routine clinical variables that are accessible to primary care physicians, such...

The subthalamic nucleus (STN) is a critical hub for inhibitory control, implicated in decision making under conflict and impulsivity. Delta frequency oscillations have also been associated with inhibitory control processes, yet the relationship between human STN neuronal activity and local delta frequencies during response inhibition remains unresolved. Here we recorded STN neurons and local field potentials in patients with Parkinson's disease performing a stop-signal reaction time task during...

The aggregation of amyloid proteins into fibrillar and oligomeric aggregates is linked to a number of neurodegenerative diseases. While the disease onset remains elusive in many cases, an understanding of the driving forces for the aggregation may help finding possible causes. While effects on amyloid formation kinetics are more commonly studied, gaining insights into these driving forces require a thermodynamic approach with equilibrium measurements. Here we investigate the temperature...