48 results match your criteria: "Convergence Research Center for Dementia[Affiliation]"

The N-degron pathway mediates the autophagic degradation of cytosolic mitochondrial DNA during sterile innate immune responses.

Cell Rep

December 2024

Cellular Degradation Biology Center and Department of Biomedical Sciences, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea; Convergence Research Center for Dementia, Seoul National University Medical Research Center, Seoul 110-799, Republic of Korea; AUTOTAC Bio, Inc., Changkkyunggung-ro 254, Jongno-gu, Seoul 03077, Republic of Korea; Ischemic/Hypoxic Disease Institute, College of Medicine, Seoul National University, Seoul 110-799, Republic of Korea. Electronic address:

The human body reacts to tissue damage by generating damage-associated molecular patterns (DAMPs) that activate sterile immune responses. To date, little is known about how DAMPs are removed to avoid excessive immune responses. Here, we show that proteasomal dysfunction induces the release of mitochondrial DNA (mtDNA) as a DAMP that activates the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon gene (STING) pathway and is subsequently degraded through the N-degron pathway.

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Background: Whether telomere length (TL), an indicator of biological ageing, reflects Alzheimer's disease (AD)-related neuropathological change remains unclear. We investigated the relationships between TL, in vivo AD pathologies, including cerebral beta-amyloid and tau deposition, and cognitive outcomes in older adults.

Methods: A total of 458 older adults were included, encompassing both cognitively normal (CN) individuals and those cognitively impaired (CI), with the CI group consisting of individuals with mild cognitive impairment or AD dementia.

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Objective: Previous studies have reported that vitamin D deficiency increased the risk of Alzheimer's disease (AD) dementia in older adults. However, little is known about how vitamin D is involved in the pathophysiology of AD. Thus, this study aimed to examine the association and interaction of serum vitamin D levels with AD pathologies including cerebral beta-amyloid (Aβ) deposition and neurodegeneration in nondemented older adults.

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Numerous systemic diseases manifest with oral symptoms and signs. The molecular diagnosis of Alzheimer's disease (AD), the most prevalent neurodegenerative disease worldwide, currently relies on invasive or expensive methods, emphasizing the imperative for easily accessible biomarkers. In this study, we explored the expression patterns of key proteins implicated in AD pathophysiology within the taste buds of mice.

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Neuropathological features of Alzheimer's disease include amyloid plaques, neurofibrillary tangles and Lewy bodies, with the former preceding the latter two. However, it is not fully understood how these compound proteinopathies are interconnected. Here, we show that transplantation of amyloid-β oligomer-activated microglia into the striatum of naïve mice was sufficient to generate all the features of Alzheimer's disease, including widespread tauopathy and synucleinopathy, gliosis, neuroinflammation, synapse loss, neuronal death, and cognitive and motor deficits.

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This study presents a preliminary exploration into the effect of Korean Red Ginseng (KRG) on the cerebellum in individuals with cerebellar atrophy. Over a three month-long period, nine subjects received a 4.5g of KRG daily, with assessments including the ARS, ADAS-Cog, and FDG-PET/CT scans.

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FGFR3 drives Aβ-induced tau uptake.

Exp Mol Med

July 2024

Department of Biomedical Science, College of Medicine, Seoul National University, Seoul, Korea.

The amyloid cascade hypothesis suggests that amyloid beta (Aβ) contributes to initiating subsequent tau pathology in Alzheimer's disease (AD). However, the underlying mechanisms through which Aβ contributes to tau uptake and propagation remain poorly understood. Here, we show that preexisting amyloid pathology accelerates the uptake of extracellular tau into neurons.

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Background: Choline alfoscerate (alpha-glycerylphosphorylcholine) is a phospholipid that includes choline, which increases the release of acetylcholine. The ASCOMALVA trial, a combination of donepezil and choline alfoscerate, slowed cognitive decline in Alzheimer disease. This study aims to replicate the effect by combining donepezil with other nootropics currently used in South Korea.

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The accurate identification of individuals without prior infection with severe acute respiratory syndrome coronavirus 2 is pivotal for seroepidemiological studies and vaccine trials. Owing to widespread vaccination against coronavirus disease 2019 (COVID-19), the anti-nucleocapsid antibody continues to serve as a valuable marker for individuals without a history of COVID-19. This study aimed to comprehensively assess anti-nucleocapsid antibody positivity using diverse commercial and in-house immunoassays among individuals who contracted COVID-19 more than three years earlier.

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CRISPR-based identification of N-terminal acetylation in synucleinopathies.

Trends Neurosci

May 2024

Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul 03080, South Korea; Neuroscience Research Institute, Seoul National University College of Medicine, Seoul, South Korea; Convergence Research Center for Dementia, Seoul National University College of Medicine, Seoul, South Korea; Neuramedy Co. Ltd, Seoul, South Korea. Electronic address:

A recent study by Kumar et al. identified several biological pathways that regulate the levels of endogenous alpha-synuclein (α-synuclein). They specifically highlighted the N-terminal acetylation (NTA) pathway as an important factor in maintaining the stability of endogenous α-synuclein, suggesting targeting the NTA pathway as a potential therapeutic approach.

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N-recognins UBR1 and UBR2 as central ER stress sensors in mammals.

Mol Cells

January 2024

Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine, Seoul 03080, Korea; Department of Biomedical Sciences, Seoul National University Graduate School, Seoul 03080, Korea; Ischemic/Hypoxic Disease Institute, Convergence Research Center for Dementia, Seoul National University College of Medicine, Seoul 03080, Korea. Electronic address:

In eukaryotes, a primary protein quality control (PQC) process involves the destruction of conformationally misfolded proteins through the ubiquitin-proteasome system. Because approximately one-third of eukaryotic proteomes fold and assemble within the endoplasmic reticulum (ER) before being sent to their destinations, the ER plays a crucial role in PQC. The specific functions and biochemical roles of several E3 ubiquitin ligases involved in ER-associated degradation in mammals, on the other hand, are mainly unknown.

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Parkinson disease (PD) characterized by dopaminergic neuronal loss is caused by aggregation of misfolded SNCA/α-synuclein. We recently developed autophagy-targeting chimera (AUTOTAC), a targeted protein degradation (TPD) technology based on the macroautophagy/autophagy-lysosome pathway (ALP). In this study, we employed AUTOTAC to synthesize ATC161, a chimeric compound that adopts Anle138b as target-binding ligand (TBL) for SNCA aggregates.

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The major neuropathologic feature of Parkinson's disease is the presence of widespread intracellular inclusions of α-synuclein known as Lewy bodies. Evidence suggests that these misfolded protein inclusions spread through the brain with disease progression. Changes in synaptic function precede neurodegeneration, and this extracellular α-synuclein can affect synaptic transmission.

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Distinct sets of lysosomal genes define synucleinopathy and tauopathy.

BMB Rep

December 2023

Department of Biomedical Sciences, Neuroscience Research Institute, Seoul National University College of Medicine, Seoul 03080, Korea; Convergence Research Center for Dementia, Seoul National University College of Medicine, Seoul 03081; Neuramedy Co. Ltd., Seoul 04796, Korea.

Neurodegenerative diseases are characterized by distinct protein aggregates, such as those of α-synuclein and tau. Lysosomal defect is a key contributor to the accumulation and propagation of aberrant protein aggregates in these diseases. The discoveries of common proteinopathies in multiple forms of lysosomal storage diseases (LSDs) and the identification of some LSD genes as susceptible genes for those proteinopathies suggest causative links between LSDs and the proteinopathies.

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Changes in oligodendroglial subpopulations in Parkinson's disease.

Mol Brain

September 2023

Department of Biomedical Sciences, Seoul National University College of Medicine, 103 Daehak-ro, Jongro-gu, Seoul, 03080, South Korea.

Parkinson's disease (PD) is characterized by a selective loss of dopaminergic neurons. While most research on PD conducted to date has focused on neurons and, to a certain extent, glia, few studies have investigated changes in oligodendroglia. Here, we investigated the heterogeneity of oligodendrocytes from PD patients compared with those of control cases by analyzing single-nuclei transcriptomes.

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In tauopathy conditions, such as Alzheimer's disease (AD), highly soluble and natively unfolded tau polymerizes into an insoluble filament; however, the mechanistic details of this process remain unclear. In the brains of AD patients, only a minor segment of tau forms β-helix-stacked protofilaments, while its flanking regions form disordered fuzzy coats. Here, it is demonstrated that the tau AD nucleation core (tau-AC) sufficiently induced self-aggregation and recruited full-length tau to filaments.

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Statins suppress cell-to-cell propagation of α-synuclein by lowering cholesterol.

Cell Death Dis

July 2023

Department of Biomedical Sciences, Neuroscience Research Institute, Convergence Research Center for Dementia, Seoul National University College of Medicine, Seoul, 03080, Republic of Korea.

Cell-to-cell propagation of protein aggregates has been implicated in the progression of neurodegenerative diseases. However, the underlying mechanism and modulators of this process are not fully understood. Here, we screened a small-molecule library in a search for agents that suppress the propagation of α-synuclein and mutant huntingtin (mHtt).

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Parkinson's disease (PD), multiple system atrophy (MSA), and dementia with Lewy bodies (DLB) are neurodegenerative disorders with alpha-synuclein (α-syn) aggregation pathology. Different strains of α-syn with unique properties are suggested to cause distinct clinical and pathological manifestations resulting in PD, MSA, or DLB. To study individual α-syn spreading patterns, we injected α-syn fibrils amplified from brain homogenates of two MSA patients and two PD patients into the brains of C57BI6/J mice.

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The N-degron pathway mediates lipophagy: The chemical modulation of lipophagy in obesity and NAFLD.

Metabolism

September 2023

Cellular Degradation Biology Center, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea; Department of Biomedical Sciences, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea; AUTOTAC Bio Inc., Changgyeonggung-Ro 254, Jongno-Gu, Seoul, 03077, Republic of Korea; Convergence Research Center for Dementia, Seoul National University Medical Research Center, Seoul, 03080, Republic of Korea; Ischemic/Hypoxic Disease Institute, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea. Electronic address:

Background And Aims: Central to the pathogenesis of nonalcoholic fatty liver disease (NAFLD) is the accumulation of lipids in the liver and various fat tissues. We aimed to elucidate the mechanisms by which lipid droplets (LDs) in the liver and adipocytes are degraded by the autophagy-lysosome system and develop therapeutic means to modulate lipophagy, i.e.

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ECPAS/Ecm29-mediated 26S proteasome disassembly is an adaptive response to glucose starvation.

Cell Rep

July 2023

Department of Biochemistry and Molecular Biology, Seoul National University College of Medicine, Seoul 03080, Korea; Department of Biomedical Sciences, Seoul National University Graduate School, Seoul 03080, Korea; Ischemic/Hypoxic Disease Institute, Convergence Research Center for Dementia, Seoul National University College of Medicine, Seoul 03080, Korea. Electronic address:

The 26S proteasome comprises 20S catalytic and 19S regulatory complexes. Approximately half of the proteasomes in cells exist as free 20S complexes; however, our mechanistic understanding of what determines the ratio of 26S to 20S species remains incomplete. Here, we show that glucose starvation uncouples 26S holoenzymes into 20S and 19S subcomplexes.

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Targeted degradation of ⍺-synuclein aggregates in Parkinson's disease using the AUTOTAC technology.

Mol Neurodegener

June 2023

Cellular Degradation Biology Center, College of Medicine, Seoul National University, Seoul, 03080, Republic of Korea.

Background: There are currently no disease-modifying therapeutics for Parkinson's disease (PD). Although extensive efforts were undertaken to develop therapeutic approaches to delay the symptoms of PD, untreated α-synuclein (α-syn) aggregates cause cellular toxicity and stimulate further disease progression. PROTAC (Proteolysis-Targeting Chimera) has drawn attention as a therapeutic modality to target α-syn.

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Parkinson's disease (PD) is a neurodegenerative disorder characterized by the aggregation of misfolded α-synuclein and progressive spreading of the aggregates from a few discrete regions to wider brain regions. Although PD has been classically considered a movement disorder, a large body of clinical evidence has revealed the progressive occurrence of non-motor symptoms. Patients present visual symptoms in the initial stages of the disease, and accumulation of phospho-α-synuclein, dopaminergic neuronal loss, and retinal thinning has been observed in the retinas of PD patients.

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