Alzheimer & Parkinson

Parkinson's disease is a neurodegenerative condition, marked by a progressive deterioration in both motor and non-motor abilities, which can severely affect the quality of life of the elderly population. With no cure available, innovative tools in treatment development and drug discovery are necessary. For several years, traditional models have been essential; however, they face limitations in replicating the complex setting of Parkinson's disease. In this regard, in silico and in vitro models...

Alzheimer's disease, the leading cause of dementia in the elderly, is a neurodegenerative disorder that has been studied to uncover therapeutic pathways through its molecular and cellular hallmarks. Here, we present a comprehensive investigation of cellular heterogeneity from the temporal cortex region of 40 individuals, comprising healthy donors and individuals with differing AD pathology. Using single-nucleus transcriptomic analysis of 430,271 nuclei from both gray and white matter of these...

The human brain is one of the most metabolically active tissues in the body, due in large part to the activity of trillions of synaptic connections. Under normal conditions, macroautophagy/autophagy at the synapse plays a crucial role in synaptic pruning and plasticity, which occurs physiologically in the absence of disease- or aging-related stressors. Disruption of autophagy has profound effects on neuron development, structure, function, and survival. Neurons are dependent upon maintaining...

The amyloid precursor protein (APP) plays a pivotal role in the pathogenesis of Alzheimer's disease (AD). While the production of Amyloid beta (Aβ) has traditionally been considered the primary cause of AD, the role of the APP intracellular domain (AICD) remains largely elusive. In this study, we established a novel model in the adult fly wing by expressing human APP, recapitulating AD-associated axon degeneration. Using this model, we discovered that ectopic APP expression in Drosophila wing...

Type 2 diabetes mellitus (T2DM) is increasingly recognized as a shared pathological substrate for both sarcopenia and cognitive decline, particularly Alzheimer's disease (AD). This review synthesizes current evidence on the converging molecular pathways linking insulin resistance, hyperglycaemia, mitochondrial dysfunction, oxidative stress, and chronic inflammation to muscle wasting and neurodegeneration. Central to this interplay is the muscle-brain axis, a bidirectional communication network...

Blood biomarkers of Alzheimer's disease (AD) are promising for dementia prediction, but their association with progression across intermediate stages of cognitive decline in the general population remains unclear. We followed 2148 dementia-free individuals from a Swedish population-based cohort for up to 16 years. Associations between baseline AD blood biomarkers and transitions between normal cognition, mild cognitive impairment (MCI), and dementia were examined. Lower amyloid-β42/40 ratio and...

Spatial disorientation is emerging as an early cognitive biomarker of dementia, but the underlying neural mechanisms remain undefined. The anterodorsal nucleus of the thalamus (ADn) exhibits early and selective vulnerability to pathological misfolded forms of tau, a major hallmark of Alzheimer's disease. As the ADn contains a high density of head direction (HD) cells, we hypothesized that ptau disrupts HD cell activity, promoting spatial disorientation. To test this, we virally expressed human...

Astrocytes play essential roles in the brain, and their dysfunction is associated with nearly every form of neurological disease. Despite their ubiquity, knowledge of how astrocytes contribute to disease pathogenesis is incomplete; accordingly, harnessing their biology toward therapeutics remains a major challenge. Here we show that the transcription factor Sox9 plays a context-specific role in maintaining astrocyte function and circuit activity in the aging hippocampus and Alzheimer's disease...

Sex-biased differences in Alzheimer's disease (AD) are well documented, but the mechanisms underlying increased vulnerability in postmenopausal women remain unclear. This study aimed to model the effects of perimenopausal hormonal fluctuations on AD pathophysiology. Using a VCD-induced accelerated ovarian failure model in young female C57BL/6 J and 3xTg mice, we simulated a perimenopausal state with hormonal changes characterised by elevated oestradiol levels and reduced progesterone levels....

Cell type-specific analysis is crucial for uncovering biological insights hidden in bulk tissue data, yet single-cell or single-nuclei approaches are often cost-prohibitive for large samples. We introduce EPIC-unmix, a novel two-step empirical Bayesian method combining reference single-cell/single-nuclei and bulk RNA-seq data to improve cell type-specific inference, accounting for the difference between reference and target datasets. Under comprehensive simulations, we demonstrate that...

Expressed in the entorhinal cortex (EC), the cholecystokinin (CCK) B receptor (CCKBR) plays an important role in memory and learning. Here, we identify that CCKBR-Gs and -Gq signaling, rather than CCKBR-Gi signaling, are beneficial for Alzheimer's disease (AD) treatment. Clinically, patients with more severe AD associated with lower CCKBR-Gq activity. The cryo-electron microscopy (cryo-EM) structures of CCKBR in complex with the endogenous agonist sulfated CCK8 (CCK8s) and 3 different G protein...

Alzheimer's disease (AD), a leading neurodegenerative disorder, involves blood-brain barrier (BBB) dysfunction as a critical contributor to its pathogenesis. This review synthesizes current advancements in in vivo magnetic resonance imaging (MRI) and positron emission tomography (PET) techniques for imaging BBB breakdown in AD. The BBB, a dynamic neurovascular interface, regulates amyloid-beta (Aβ) and tau clearance through specialized transporters and cellular interactions. BBB dysfunction,...

Alzheimer's disease (AD) is a complex neurodegenerative disorder driven by multilayered molecular and cellular mechanisms that cannot be fully elucidated through single-omics approaches. Consequently, large-scale multi-omics integration-encompassing transcriptomics, epigenomics (e.g., methylation), and genetic association studies (GWAS/eQTL/mQTL)-has uncovered critical genetic and epigenetic networks underlying disease risk and progression.Based on these integrative insights, this review...

Alzheimer's disease (AD), the most prevalent neurodegenerative disorder, remains a global health crisis due to the lack of early diagnostic tools, dynamic monitoring strategies, and effective therapies. Current diagnostic methods such as cerebrospinal fluid (CSF) analysis and neuroimaging, while accurate, are invasive, expensive, and unsuitable for routine screening, highlighting the pressing need for alternative approaches. This review comprehensively examines the transformative role of...

Cognitive and behavioral deficits in Alzheimer's disease (AD) and frontotemporal dementia (FTD) arise alongside gray matter atrophy and altered functional connectivity, yet the structure-function relationship across the dementia spectrum remains unclear. Here we combine structural and functional MRI from 221 patients-AD (n = 82), behavioral variant FTD (n = 41), corticobasal syndrome (n = 27), and nonfluent (n = 34) or semantic (n = 37) variant primary progressive aphasia-and 100 cognitively...

Spermine, a pivotal player in biomolecular condensation and diverse cellular processes, has emerged as a focus of investigation in aging, neurodegeneration, and other diseases. Despite its significance, the mechanistic details of spermine remain incompletely understood. Here, we describe the distinct modulation by spermine on Alzheimer's Tau and Parkinson's α-synuclein, elucidating their condensation behaviors in vitro and in vivo. Using biophysical techniques including time-resolved SAXS and...

Brain atrophy is a key factor behind episodic memory loss in aging, but the nature and ubiquity of this relationship remains poorly understood. This study leverages 13 longitudinal datasets, including 3737 cognitively healthy adults (10,343 MRI scans; 13,460 memory assessments), to determine whether brain change-memory change associations are more pronounced with age and genetic risk for Alzheimer's Disease. Both factors are associated with accelerated brain decline, yet it remains unclear...

Alzheimer's disease (AD) is characterized by the accumulation of amyloid beta, which is strongly associated with disease progression and cognitive decline. Despite the approval of monoclonal antibodies targeting Aβ, optimizing treatment strategies while minimizing side effects remains a challenge. This study develops a mathematical framework to model Aβ aggregation dynamics, capturing the transition from monomers to higher-order aggregates, including protofibrils, toxic oligomers, and fibrils,...

Impairment of axonal transport has been emphasized as a common feature in a series of neurodegenerative diseases (NDs). Variations in DCTN1 have been reported in NDs such as Parkinson's disease (PD), Perry syndrome (PS) and Amyotrophic lateral sclerosis (ALS). The overall objective of this study was to investigate the contribution of DCTN1 variants in different NDs and to explore the correlation between DCTN1 variants and disease phenotypes. We identified a previously published mutation p.G71E...

Patients with Alzheimer's disease (AD) initially show temporally graded retrograde amnesia, which gradually progresses into more severe retrograde amnesia. Although mouse models of AD have provided insight into neurobiological mechanisms contributing to impaired formation and retrieval of new memories, the process underlying the progressive loss of remote memories in AD has remained elusive. Here, we demonstrate age-dependent remote memory decline in APP/PS1 mice, which coincides with...