Alzheimer & Parkinson

Repetitive DNA sequences can adopt alternative (i.e., non-B) DNA structures, which represent an endogenous source of genetic instability. Z-DNA, a non-B-DNA structure, has been implicated in the development of age-related genetic disorders such as cancer and Alzheimer's disease. Previously, we found that Z-DNA is mutagenic in mammals; however, the impact of age on Z-DNA-induced genetic instability has not yet been explored. Here, we investigated the effects of aging on Z-DNA-induced genetic...

The proteinopathy of the RNA-binding protein TDP-43, characterized by nuclear clearance and cytoplasmic inclusion, is a hallmark of multiple neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and Alzheimer's disease (AD). Through CRISPR interference (CRISPRi) screening in human neurons, we identified the decapping scavenger enzyme (DCPS) as a novel genetic modifier of TDP-43 loss-of-function (LOF)-mediated neurotoxicity. Our findings reveal...

No abstract

This article aims to comprehensively analyze the vascular factors in Alzheimer's Disease (AD), particularly the changes in the carotid arteries, and their complex correlations with hippocampal atrophy and cognitive function. Besides the traditional β-amyloid protein (Aβ) and Tau protein hypotheses, vascular factors are increasingly regarded as crucial factors in the development of AD. This article systematically reviews the roles of cerebral blood flow perfusion changes and micro-infarctions in...

The accumulation of amyloid β (Aβ) protein in the brain is a central pathological hallmark of Alzheimer's disease (AD). This process has become a major focus of interdisciplinary research and a critical target in drug development. Aβ is produced through the proteolytic processing of amyloid precursor protein (APP) by a group of enzymes known as secretases. They belong to different protease classes and operate through proteolytic cleavage of the peptide bond through several catalytic hydrolysis....

The core pathological hallmark of Parkinson's disease (PD) is the progressive degeneration of dopaminergic (DAergic) neurons in the substantia nigra pars compacta (SNpc), driven by misfolding and aggregation of a-synuclein (aSyn) into Lewy bodies. This triggers severe cellular dysfunction, including endoplasmic reticulum (ER) stress and the dysregulation of the unfolded protein response (UPR). TMBIM6, an anti-apoptotic ER protein, inhibits the UPR sensor IRE1a. Although TMBIM6 exhibits...

The physical and social exposome affects human aging, and brain clocks may track its effects. However, most studies neglect multidomain exposures (physical, social and political) across diverse settings globally and their associations with brain aging. In this study, we characterized the associations between 73 country-level physical and social exposomal factors and multimodal brain age in 18,701 participants from 34 countries (healthy individuals and those with Alzheimer's disease,...

Despite advances in understanding the mechanisms, risk factors and treatment strategies for Alzheimer's disease (AD), no approved therapies exist to prevent or delay onset in at-risk individuals or those with elevated biomarkers who do not yet show symptoms. Multiple candidate interventions are now being evaluated in clinical trials in these settings, raising key questions around which populations are most appropriate and what criteria should guide regulatory and clinical decision-making. Data...

The full impact of APOE4 (apolipoprotein E4), the strongest genetic risk factor for Alzheimer's disease (AD), on neuronal and network function remains unclear, particularly during early preclinical stages of disease. Here we show that young APOE4 knockin (E4-KI) mice exhibit hippocampal region-specific network hyperexcitability that predicts later cognitive deficits. This early phenotype arises from cell-type-specific subpopulations of smaller, hyperexcitable neurons and is eliminated by...

Postoperative delirium (POD) accelerates the transition from mild cognitive impairment (MCI) to Alzheimer's disease (AD) in elderly patients. Microglial metabolic reprogramming, a pivotal aspect of the immune-inflammatory response, modulates microglia-neuron interactions and postoperative cognitive function through microenvironmental alterations. Aberrant overexpression of RUVBL2 disrupts metabolic homeostasis, leading to stress granule (SG) aggregation and fibrosis. This study investigated the...

Recent human genetic studies have highlighted the potential role of microglial genes and their regulatory functions in the pathogenesis of Alzheimer's disease (AD). The transcription factor PU.1 (encoded by SPI1) is expressed mainly in microglia in the central nervous system and has been reported to be a genetic risk factor for AD. However, the role of microglial SPI1 in AD etiology is still poorly understood. Here, we demonstrate that the selective deletion of Spi1 in microglia exacerbates...

Rapid advancements in single-cell RNA sequencing (scRNA-seq) technologies revealed the richness of myriad attributes encompassing cell identity. However, the complexity of the data hinders tasks focusing on a specific biological signal. To address this challenge, we introduce bioIB, a framework based on the information bottleneck method, designed to extract an interpretable compressed representation of scRNA-seq data, optimally informative with respect to a specific biological signal, such as...

Neural damage at any level of the neuraxis can lead to urogenital dysfunction, involving the lower urinary tract (LUT) and/or the sexual organs. The LUT consists of the bladder and the urethra (plus the prostate in males); LUT dysfunction can manifest as an underactive bladder, leading to urinary retention, or as an overactive bladder, leading to urinary incontinence. Manifestations of sexual dysfunction include loss of libido and dysfunction of erection, ejaculation and orgasm. In this Review,...

Growing use of p-tau217 raises concerns about testing in healthy people.

The integrated stress response (ISR) is essential for cellular homeostasis and cognitive function. We investigated how persistent ISR activation affects cognitive performance by studying the PPP1R15B^(R658C) genetic variant associated with intellectual disability. To model this condition, we generated a mouse line with the pathogenic allele inserted. This variant destabilized the PPP1R15B•PP1 phosphatase complex, causing persistent ISR activation, impaired protein synthesis, and long-term memory...

The endolysosomal phospholipid bis(monoacylglycerol)phosphate (BMP) is aberrantly elevated in urine from Parkinson's patients carrying mutations in leucine-rich repeat kinase 2 (LRRK2) and glucocerebrosidase (GCase). Because BMP resides on, and regulates biogenesis of, endolysosomal intralumenal membranes that become extracellular vesicles (EVs) upon release, we hypothesized that increased urinary BMP reflects enhanced exocytosis of BMP-enriched EVs. We analyzed BMP metabolism and EV-associated...

Gastrointestinal dysfunction often precedes motor symptoms in Parkinson's disease (PD), suggesting the enteric nervous system (ENS) is central to early pathogenesis. How α-synuclein contributes to ENS dysfunction, and how inflammation modulates this, remains unclear. Here we show that Tumor Necrosis Factor alpha enhances α-synuclein accumulation in induced pluripotent stem cell-derived enteric neurons and glia, and impairs the malate-aspartate shuttle, a key pathway for mitochondrial energy...

Synucleinopathies is an umbrella term for multiple neurological disorders, including Parkinson's disease (PD), Lewy body dementia (LBD), and multiple system atrophy (MSA). A central pathological hallmark of synucleinopathies is the aggregation of α-synuclein (αS, a neuronal protein) and its prion-like spread. Therefore, inhibition of αS aggregation and spread is considered a viable therapeutic approach for the treatment of synucleinopathies. Foldamers are synthetic ligands that mimic the...

Memory-based cognition relies on the integrity of cortico-hippocampal circuits, which are compromised in Alzheimer's disease (AD) as β-amyloid (Aβ) and tau accumulate. However, the mechanisms linking this pathology to circuit dysfunction remain unclear. In mouse models, using in vivo two-photon and Neuropixels recordings, we show that Aβ-tau pathology promotes both region- and layer-specific impairments, involving reduced burst firing in superficial cortical layers and CA1 and reduced mean...

No abstract