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1.
Brain ; 147(4): 1399-1411, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-37972275

RESUMEN

The most frequent neurodegenerative proteinopathies include diseases with deposition of misfolded tau or α-synuclein in the brain. Pathological protein aggregates in the PNS are well-recognized in α-synucleinopathies and have recently attracted attention as a diagnostic biomarker. However, there is a paucity of observations in tauopathies. To characterize the involvement of the PNS in tauopathies, we investigated tau pathology in cranial and spinal nerves (PNS-tau) in 54 tauopathy cases [progressive supranuclear palsy (PSP), n = 15; Alzheimer's disease (AD), n = 18; chronic traumatic encephalopathy (CTE), n = 5; and corticobasal degeneration (CBD), n = 6; Pick's disease, n = 9; limbic-predominant neuronal inclusion body 4-repeat tauopathy (LNT), n = 1] using immunohistochemistry, Gallyas silver staining, biochemistry, and seeding assays. Most PSP cases revealed phosphorylated and 4-repeat tau immunoreactive tau deposits in the PNS as follows: (number of tau-positive cases/available cases) cranial nerves III: 7/8 (88%); IX/X: 10/11 (91%); and XII: 6/6 (100%); anterior spinal roots: 10/10 (100%). The tau-positive inclusions in PSP often showed structures with fibrillary (neurofibrillary tangle-like) morphology in the axon that were also recognized with Gallyas silver staining. CBD cases rarely showed fine granular non-argyrophilic tau deposits. In contrast, tau pathology in the PNS was not evident in AD, CTE and Pick's disease cases. The single LNT case also showed tau pathology in the PNS. In PSP, the severity of PNS-tau involvement correlated with that of the corresponding nuclei, although, occasionally, p-tau deposits were present in the cranial nerves but not in the related brainstem nuclei. Not surprisingly, most of the PSP cases presented with eye movement disorder and bulbar symptoms, and some cases also showed lower-motor neuron signs. Using tau biosensor cells, for the first time we demonstrated seeding capacity of tau in the PNS. In conclusion, prominent PNS-tau distinguishes PSP from other tauopathies. The morphological differences of PNS-tau between PSP and CBD suggest that the tau pathology in PNS could reflect that in the central nervous system. The high frequency and early presence of tau lesions in PSP suggest that PNS-tau may have clinical and biomarker relevance.


Asunto(s)
Enfermedad de Alzheimer , Enfermedad de Pick , Parálisis Supranuclear Progresiva , Tauopatías , Humanos , Parálisis Supranuclear Progresiva/patología , Proteínas tau/metabolismo , Enfermedad de Pick/patología , Enfermedad de Alzheimer/patología , Tauopatías/patología , Nervios Espinales , Biomarcadores
2.
Neurobiol Dis ; 197: 106535, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38761956

RESUMEN

BACKGROUND: Multiple system atrophy (MSA) is a primary oligodendroglial synucleinopathy, characterized by elevated iron burden in early-affected subcortical nuclei. Although neurotoxic effects of brain iron deposition and its relationship with α-synuclein pathology have been demonstrated, the exact role of iron dysregulation in MSA pathogenesis is unknown. Therefore, advancing the understanding of iron dysregulation at the cellular level is critical, especially in relation to α-synuclein cytopathology. METHODS: Iron burden in subcortical and brainstem regions were histologically mapped in human post-mortem brains of 4 MSA-parkinsonian (MSA-P), 4 MSA-cerebellar (MSA-C), and 1 MSA case with both parkinsonian and cerebellar features. We then performed the first cell type-specific evaluation of pathological iron deposition in α-synuclein-affected and -unaffected cells of the globus pallidus, putamen, and the substantia nigra, regions of highest iron concentration, using a combination of iron staining with immunolabelling. Selective regional and cellular vulnerability patterns of iron deposition were compared between disease subtypes. In 7 MSA cases, expression of key iron- and closely related oxygen-homeostatic genes were examined. RESULTS: MSA-P and MSA-C showed different patterns of regional iron burden across the pathology-related systems. We identified subcortical microglia to predominantly accumulate iron, which was more distinct in MSA-P. MSA-C showed relatively heterogenous iron accumulation, with greater or similar deposition in astroglia. Iron deposition was also found outside cellular bodies. Cellular iron burden associated with oligodendrocytic, and not neuronal, α-synuclein cytopathology. Gene expression analysis revealed dysregulation of oxygen homeostatic genes, rather than of cellular iron. Importantly, hierarchal cluster analysis revealed the pattern of cellular vulnerability to iron accumulation, distinctly to α-synuclein pathology load in the subtype-related systems, to distinguish MSA subtypes. CONCLUSIONS: Our comprehensive evaluation of iron deposition in MSA brains identified distinct regional, and for the first time, cellular distribution of iron deposition in MSA-P and MSA-C and revealed cellular vulnerability patterns to iron deposition as a novel neuropathological characteristic that predicts MSA clinical subtypes. Our findings suggest distinct iron-related pathomechanisms in MSA clinical subtypes that are therefore not a consequence of a uniform down-stream pathway to α-synuclein pathology, and inform current efforts in iron chelation therapies at the disease and cellular-specific levels.


Asunto(s)
Hierro , Atrofia de Múltiples Sistemas , alfa-Sinucleína , Humanos , Atrofia de Múltiples Sistemas/metabolismo , Atrofia de Múltiples Sistemas/patología , Hierro/metabolismo , Masculino , Anciano , Femenino , Persona de Mediana Edad , alfa-Sinucleína/metabolismo , Encéfalo/metabolismo , Encéfalo/patología , Anciano de 80 o más Años , Oligodendroglía/metabolismo , Oligodendroglía/patología
3.
Neurobiol Dis ; 198: 106551, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38839023

RESUMEN

Multiple system atrophy (MSA) is characterized by glial cytoplasmic inclusions (GCIs) containing aggregated α-synuclein (α-syn) in oligodendrocytes. The origin of α-syn accumulation in GCIs is unclear, in particular whether abnormal α-syn aggregates result from the abnormal elevation of endogenous α-syn expression in MSA or ingested from the neuronal source. Tubulin polymerization promoting protein (TPPP) has been reported to play a crucial role in developing GCI pathology. Here, the total cell body, nucleus, and cytoplasmic area density of SNCA and TPPP transcripts in neurons and oligodendrocytes with and without various α-syn pathologies in the pontine base in autopsy cases of MSA (n = 4) and controls (n = 2) were evaluated using RNAscope with immunofluorescence. Single-nucleus RNA-sequencing data for TPPP was evaluated using control frontal cortex (n = 3). SNCA and TPPP transcripts were present in the nucleus and cytoplasm of oligodendrocytes in both controls and diseased, with higher area density in GCIs and glial nuclear inclusions in MSA. Area densities of SNCA and TPPP transcripts were lower in neurons showing cytoplasmic inclusions in MSA. Indeed, TPPP transcripts were unexpectedly found in neurons, while the anti-TPPP antibody failed to detect immunoreactivity. Single-nucleus RNA-sequencing revealed significant TPPP transcript expression predominantly in oligodendrocytes, but also in excitatory and inhibitory neurons. This study addressed the unclear origin of accumulated α-syn in GCIs, proposing that the elevation of SNCA transcripts may supply templates for misfolded α-syn. In addition, the parallel behavior of TPPP and SNCA transcripts in GCI development highlights their potential synergistic contribution to inclusion formation. In conclusion, this study advances our understanding of MSA pathogenesis, offers insights into the dynamics of SNCA and TPPP transcripts in inclusion formation, and proposes regulating their transcripts for future molecular therapy to MSA.


Asunto(s)
Cuerpos de Inclusión , Atrofia de Múltiples Sistemas , Proteínas del Tejido Nervioso , Oligodendroglía , alfa-Sinucleína , alfa-Sinucleína/metabolismo , alfa-Sinucleína/genética , Atrofia de Múltiples Sistemas/genética , Atrofia de Múltiples Sistemas/patología , Atrofia de Múltiples Sistemas/metabolismo , Humanos , Oligodendroglía/metabolismo , Oligodendroglía/patología , Cuerpos de Inclusión/metabolismo , Cuerpos de Inclusión/patología , Cuerpos de Inclusión/genética , Anciano , Femenino , Masculino , Persona de Mediana Edad , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Neuronas/metabolismo , Neuronas/patología , Anciano de 80 o más Años
4.
Biochem Cell Biol ; 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38996387

RESUMEN

Over the past four decades, prion diseases have received considerable research attention owing to their potential to be transmitted within and across species as well as their consequences for human and animal health. The unprecedented nature of prions has led to the discovery of a paradigm of templated protein misfolding that underlies a diverse range of both disease-related and normal biological processes. Indeed, the "prion-like" misfolding and propagation of protein aggregates is now recognized as a common underlying disease mechanism in human neurodegenerative disorders such as Alzheimer's and Parkinson's disease and the prion principle has led to the development of novel diagnostic and therapeutic strategies for these illnesses. Despite these advances, research into the fundamental biology of prion diseases has declined, likely due to their rarity and the absence of an acute human health crisis. Given the past translational influence, continued research on the etiology, pathogenesis, and transmission of prion disease should remain a priority. In this review we highlight several important "unsolved mysteries" in the prion disease research field and how solving them may be crucial for the development of effective therapeutics, preventing future outbreaks of prion disease, and understanding the pathobiology of more common human neurodegenerative disorders.

5.
Neuropathol Appl Neurobiol ; 50(4): e13000, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39036836

RESUMEN

AIMS: Astrocytic tau pathology is a major feature of tauopathies and ageing-related tau astrogliopathy (ARTAG). The substantia nigra (SN) is one of the important degenerative areas in tauopathies with parkinsonism. Nigral tau pathology is usually reported as neuronal predominant with less prominent astrocytic involvement. We aimed to identify cases with prominent astrocytic tau pathology in the SN. METHODS: We use the term nigral tau-astrogliopathy (NITAG) to describe cases showing an unusually high density of ARTAG with less neuronal tau pathology in the SN. We collected clinical information and studied the distribution of tau pathology, morphological features and immunostaining profiles in three cases. RESULTS: Three cases, all males with parkinsonism, were identified with the following clinicopathological diagnoses: (i) atypical parkinsonism with tau pathology reminiscent to that in postencephalitic parkinsonism (69-year-old); (ii) multiple system atrophy (73-year-old); (iii) traumatic encephalopathy syndrome/chronic traumatic encephalopathy (84-year-old). Double-labelling immunofluorescence confirmed co-localization of GFAP and phosphorylated tau in affected astrocytes. Staining profiles of NITAG revealed immunopositivity for various phosphorylated tau antibodies. Some astrocytic tau lesions were also seen in other brainstem regions and cerebral grey matter. CONCLUSIONS: We propose NITAG is a rare neuropathological feature, and not a distinct disease entity, in the frame of multiple system ARTAG, represented by abundant tau-positive astrocytes in various brain regions but having the highest density in the SN. The concept of NITAG allows the stratification of cases with various background pathologies to understand its relevance and contribution to neuronal dysfunction.


Asunto(s)
Envejecimiento , Astrocitos , Sustancia Negra , Tauopatías , Proteínas tau , Humanos , Masculino , Sustancia Negra/patología , Sustancia Negra/metabolismo , Anciano , Astrocitos/patología , Astrocitos/metabolismo , Tauopatías/patología , Tauopatías/metabolismo , Anciano de 80 o más Años , Envejecimiento/patología , Proteínas tau/metabolismo , Trastornos Parkinsonianos/patología , Trastornos Parkinsonianos/metabolismo
6.
Ann Neurol ; 93(3): 431-445, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36309960

RESUMEN

OBJECTIVE: Progressive supranuclear palsy (PSP) is a 4R-tauopathy showing heterogeneous tau cytopathology commencing in the globus pallidus (GP) and the substantia nigra (SN), regions also associated with age-related iron accumulation. Abnormal iron levels have been extensively associated with tau pathology in neurodegenerative brains, however, its role in PSP pathogenesis remains yet unknown. We perform the first cell type-specific evaluation of PSP iron homeostasis and the closely related oxygen homeostasis, in relation to tau pathology in human postmortem PSP brains. METHODS: In brain regions vulnerable to PSP pathology (GP, SN, and putamen), we visualized iron deposition in tau-affected and unaffected neurons, astroglia, oligodendrocytes, and microglia, using a combination of iron staining with immunolabelling. To further explore molecular pathways underlying our observations, we examined the expression of key iron and oxygen homeostasis mRNA transcripts and proteins. RESULTS: We found astrocytes as the major cell type accumulating iron in the early affected regions of PSP, highly associated with cellular tau pathology. The same regions are affected by dysregulated expression of alpha and beta hemoglobin and neuroglobin showing contrasting patterns. We discovered changes in iron and oxygen homeostasis-related gene expression associated with aging of the brain, and identified dysregulated expression of rare neurodegeneration with brain iron accumulation (NBIA) genes associated with tau pathology to distinguish PSP from the healthy aging brain. INTERPRETATION: We present novel aspects of PSP pathophysiology highlighting an overlap with NBIA pathways. Our findings reveal potential novel targets for therapy development and have implications beyond PSP for other iron-associated neurodegenerative diseases. ANN NEUROL 2023;93:431-445.


Asunto(s)
Hierro , Parálisis Supranuclear Progresiva , Humanos , Hierro/metabolismo , Proteínas tau/metabolismo , Parálisis Supranuclear Progresiva/metabolismo , Encéfalo/patología , Oxígeno
7.
Int J Mol Sci ; 25(8)2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38673855

RESUMEN

Iron accumulation in the brain is a common feature of many neurodegenerative diseases. Its involvement spans across the main proteinopathies involving tau, amyloid-beta, alpha-synuclein, and TDP-43. Accumulating evidence supports the contribution of iron in disease pathologies, but the delineation of its pathogenic role is yet challenged by the complex involvement of iron in multiple neurotoxicity mechanisms and evidence supporting a reciprocal influence between accumulation of iron and protein pathology. Here, we review the major proteinopathy-specific observations supporting four distinct hypotheses: (1) iron deposition is a consequence of protein pathology; (2) iron promotes protein pathology; (3) iron protects from or hinders protein pathology; and (4) deposition of iron and protein pathology contribute parallelly to pathogenesis. Iron is an essential element for physiological brain function, requiring a fine balance of its levels. Understanding of disease-related iron accumulation at a more intricate and systemic level is critical for advancements in iron chelation therapies.


Asunto(s)
Hierro , Enfermedades Neurodegenerativas , Humanos , Hierro/metabolismo , Enfermedades Neurodegenerativas/metabolismo , Animales , Proteínas tau/metabolismo , Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Encéfalo/patología , alfa-Sinucleína/metabolismo , Proteínas de Unión al ADN/metabolismo , Quelantes del Hierro/uso terapéutico
8.
Int J Mol Sci ; 25(5)2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38473923

RESUMEN

Lewy body diseases (LBDs) feature α-synuclein (α-syn)-containing Lewy bodies, with misfolded α-syn potentially propagating as seeds. Using a seeding amplification assay, we previously reported distinct α-syn seeding in LBD cases based on the area under seeding curves. This study revealed that LBD cases showing different α-syn seeding kinetics have distinct proteomics profiles, emphasizing disruptions in mitochondria and lipid metabolism in high-seeder cases. Though the mechanisms underlying LBD development are intricate, the factors influencing α-syn seeding activity remain elusive. To address this and complement our previous findings, we conducted targeted transcriptome analyses in the substantia nigra using the nanoString nCounter assay together with histopathological evaluations in high (n = 4) and low (n = 3) nigral α-syn seeders. Neuropathological findings (particularly the substantia nigra) were consistent between these groups and were characterized by neocortical LBD associated with Alzheimer's disease neuropathologic change. Among the 1811 genes assessed, we identified the top 20 upregulated and downregulated genes and pathways in α-syn high seeders compared with low seeders. Notably, alterations were observed in genes and pathways related to transmembrane transporters, lipid metabolism, and the ubiquitin-proteasome system in the high α-syn seeders. In conclusion, our findings suggest that the molecular behavior of α-syn is the driving force in the neurodegenerative process affecting the substantia nigra through these identified pathways. These insights highlight their potential as therapeutic targets for attenuating LBD progression.


Asunto(s)
Enfermedad por Cuerpos de Lewy , alfa-Sinucleína , Humanos , alfa-Sinucleína/metabolismo , Enfermedad por Cuerpos de Lewy/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Metabolismo de los Lípidos , Ubiquitinas/metabolismo
9.
Acta Neuropathol ; 146(3): 395-414, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37354322

RESUMEN

Microtubule-associated protein tau (MAPT) aggregates in neurons, astrocytes and oligodendrocytes in a number of neurodegenerative diseases, including progressive supranuclear palsy (PSP). Tau is a target of therapy and the strategy includes either the elimination of pathological tau aggregates or reducing MAPT expression, and thus the amount of tau protein made to prevent its aggregation. Disease-associated tau affects brain regions in a sequential manner that includes cell-to-cell spreading. Involvement of glial cells that show tau aggregates is interpreted as glial cells taking up misfolded tau assuming that glial cells do not express enough MAPT. Although studies have evaluated MAPT expression in human brain tissue homogenates, it is not clear whether MAPT expression is compromised in cells accumulating pathological tau. To address these perplexing aspects of disease pathogenesis, this study used RNAscope combined with immunofluorescence (AT8), and single-nuclear(sn) RNAseq to systematically map and quantify MAPT expression dynamics across different cell types and brain regions in controls (n = 3) and evaluated whether tau cytopathology affects MAPT expression in PSP (n = 3). MAPT transcripts were detected in neurons, astrocytes and oligodendrocytes, and varied between brain regions and within each cell type, and were preserved in all cell types with tau aggregates in PSP. These results propose a complex scenario in all cell types, where, in addition to the ingested misfolded tau, the preserved cellular MAPT expression provides a pool for local protein production that can (1) be phosphorylated and aggregated, or (2) feed the seeding of ingested misfolded tau by providing physiological tau, both accentuating the pathological process. Since tau cytopathology does not compromise MAPT gene expression in PSP, a complete loss of tau protein expression as an early pathogenic component is less likely. These observations provide rationale for a dual approach to therapy by decreasing cellular MAPT expression and targeting removal of misfolded tau.


Asunto(s)
Parálisis Supranuclear Progresiva , Proteínas tau , Humanos , Proteínas tau/genética , Proteínas tau/metabolismo , Parálisis Supranuclear Progresiva/patología , Citología , Neuroglía/patología , Neuronas/patología , Expresión Génica
10.
Int J Mol Sci ; 24(14)2023 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-37511361

RESUMEN

Limited comparative data exist on the molecular spectrum of amyloid-beta (Aß) and tau deposition in individuals with Down syndrome (DS) and sporadic Alzheimer's disease (sAD). We assessed Aß and tau deposition severity in the temporal lobe and cerebellum of ten DS and ten sAD cases. Immunohistochemistry was performed using antibodies against eight different Aß epitopes (6F/3D, Aß38, Aß39, Aß40, Aß42, Aß43, pyroglutamate Aß at third glutamic acid (AßNp3E), phosphorylated- (p-)Aß at 8th serine (AßpSer8)), and six different pathological tau epitopes (p-Ser202/Thr205, p-Thr231, p-Ser396, Alz50, MC1, GT38). Findings were evaluated semi-quantitatively and quantitatively using digital pathology. DS cases had significantly higher neocortical parenchymal deposition (Aß38, Aß42, and AßpSer8), and cerebellar parenchymal deposition (Aß40, Aß42, AßNp3E, and AßpSer8) than sAD cases. Furthermore, DS cases had a significantly larger mean plaque size (6F/3D, Aß42, AßNp3E) in the temporal lobe, and significantly greater deposition of cerebral and cerebellar Aß42 than sAD cases in the quantitative analysis. Western blotting corroborated these findings. Regarding tau pathology, DS cases had significantly more severe cerebral tau deposition than sAD cases, especially in the white matter (p-Ser202/Thr205, p-Thr231, Alz50, and MC1). Greater total tau deposition in the white matter (p-Ser202/Thr205, p-Thr231, and Alz50) of DS cases was confirmed by quantitative analysis. Our data suggest that the Aß and tau molecular signatures in DS are distinct from those in sAD.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Síndrome de Down , Proteínas tau , Humanos , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/genética , Péptidos beta-Amiloides/metabolismo , Cerebelo/metabolismo , Síndrome de Down/genética , Síndrome de Down/metabolismo , Síndrome de Down/patología , Fragmentos de Péptidos , Proteínas tau/genética , Proteínas tau/metabolismo , Lóbulo Temporal/metabolismo
11.
J Happiness Stud ; 24(2): 745-767, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36686601

RESUMEN

Social interaction is an important source of psychological and physical well-being during normal times. However, following the COVID-19 outbreak, which spreads rapidly from person to person, social interaction poses a fatal threat to one's health and life. Therefore, several countries including South Korea implemented an intense social distancing mandate to prevent the spread of the virus. During these unique times of pandemic, the current research investigated whether and how an individual's well-being varies as a function of their interaction with various relationship partners using experience sampling data (Study 1) and online longitudinal data (Study 2). The results indicated that being alone was more detrimental to well-being during the pandemic than before it. Specifically, interaction with close relationship partners (e.g., romantic partner, spouse, or friend) was positively related to well-being, whereas interaction with formal relationship partners (e.g., coworker, boss) was negatively linked to momentary well-being during the pandemic. Furthermore, our study showed that the association between social supports from close relationships and well-being was temporally strengthened during COVID-19 pandemic. In sum, the benefits of close relationships on well-being were stronger during the COVID-19 pandemic than before it.

12.
Acta Neuropathol ; 144(4): 637-650, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35780436

RESUMEN

In Alzheimer's disease (AD), where amyloid-ß (Aß) and tau deposits in the brain, hyperexcitation of neuronal networks is an underlying disease mechanism, but its cause remains unclear. Here, we used the Collaborative Cross (CC) forward genetics mouse platform to identify modifier genes of neuronal hyperexcitation. We found LAMP5 as a novel regulator of hyperexcitation in mice, critical for the survival of distinct interneuron populations. Interestingly, synaptic LAMP5 was lost in AD brains and LAMP5 interneurons degenerated in different AD mouse models. Genetic reduction of LAMP5 augmented functional deficits and neuronal network hypersynchronicity in both Aß- and tau-driven AD mouse models. To this end, our work defines the first specific function of LAMP5 interneurons in neuronal network hyperexcitation in AD and dementia with tau pathology.


Asunto(s)
Enfermedad de Alzheimer , Proteínas de Membrana de los Lisosomas/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/fisiología , Animales , Modelos Animales de Enfermedad , Interneuronas/patología , Ratones , Ratones Transgénicos , Neuronas/patología , Proteínas tau/genética
13.
Eur J Neurol ; 29(8): 2220-2231, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35384155

RESUMEN

BACKGROUND AND PURPOSE: Progressive supranuclear palsy (PSP) encompasses a broader range of disease courses than previously appreciated. The most frequent clinical presentations of PSP are Richardson syndrome (RS) and PSP with a predominant Parkinsonism phenotype (PSP-P). Time to reach gait dependence and cognitive impairment have been proposed as prognostic disease milestones. Genetic polymorphisms in TRIM11 and SLC2A13 genes have been associated with longer disease duration (DD). METHODS: Methods used include retrospective chart review, genetic single nucleotide polymorphism analyses (in three cases), and neuropathology. RESULTS: We identified four cases with long (>10-15 years) or very long (>15 years) DD. Stage 1 PSP tau pathology was present in two cases (one PSP-P and one undifferentiated phenotype), whereas pallidonigroluysian atrophy (PSP-RS) and Stage 4/6 (PSP-P) PSP pathology were found in the other two cases. Three cases were homozygous for the rs564309-C allele of the TRIM11 gene and the H1 MAPT haplotype. Two were heterozygous for rs2242367 (G/A) in SLC2A13, whereas the third was homozygous for the G-allele. CONCLUSIONS: We propose a protracted course subtype of PSP (PC-PSP) based on clinical or neuropathological criteria in two cases with anatomically restricted PSP pathology, and very long DD and slower clinical progression in the other two cases. The presence of the rs564309-C allele may influence the protracted disease course. Crystallizing the concept of PC-PSP is important to further understand the pathobiology of tauopathies in line with current hypotheses of protein misfolding, seeding activity, and propagation.


Asunto(s)
Trastornos Parkinsonianos , Parálisis Supranuclear Progresiva , Progresión de la Enfermedad , Proteínas Facilitadoras del Transporte de la Glucosa/genética , Humanos , Trastornos Parkinsonianos/patología , Polimorfismo de Nucleótido Simple , Estudios Retrospectivos , Parálisis Supranuclear Progresiva/patología , Tauopatías/patología , Proteínas de Motivos Tripartitos/genética , Ubiquitina-Proteína Ligasas/genética , Proteínas tau/metabolismo
14.
Angew Chem Int Ed Engl ; 60(14): 7873-7879, 2021 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-33403785

RESUMEN

Through the formation of an electron donor-acceptor (EDA) complex, strain-release aminopyridylation of [1.1.1]propellane with N-aminopyridinium salts as bifunctional reagents enabled the direct installation of amino and pyridyl groups onto bicyclo[1.1.1]pentane (BCP) frameworks in the absence of an external photocatalyst. The robustness of this method to synthesize 1,3-aminopyridylated BCPs under mild and metal-free conditions is highlighted by the late-stage modification of structurally complex biorelevant molecules. Moreover, the strategy was extended to P-centered and CF3 radicals for the unprecedented incorporation of such functional groups with pyridine across the BCP core in a three-component coupling. This practical method lays the foundation for the straightforward construction of new valuable C4-pyridine-functionalized BCP chemical entities, thus significantly expanding the range of accessibility of BCP-type bioisosteres for applications in drug discovery.

15.
FASEB J ; 33(3): 4341-4354, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30592630

RESUMEN

Fibrosis is characterized by the increased accumulation of extracellular matrix (ECM), which drives abnormal cell proliferation and progressive organ dysfunction in many inflammatory and metabolic diseases. Studies have shown that halofuginone, a racemic halogenated derivative, inhibits glutamyl-prolyl-transfer RNA-synthetase (EPRS)-mediated fibrosis. However, the mechanism by which this occurs is unclear. We explored the mechanistic aspects of how EPRS could develop liver fibrotic phenotypes in cells and animal models. Treatment with TGF-ß1 up-regulated fibronectin and collagen I levels in LX2 hepatic stellate cells. This effect was inhibited in prolyl-transfer RNA synthetase (PRS)-suppressed LX2 cells. Using the promoter luciferase assay, TGF-ß1-mediated collagen I, α1 chain transcription and γ2 basal laminin transcription in LX2 cells were down-regulated by EPRS suppression, suggesting that EPRS may play roles in ECM production at transcriptional levels. Furthermore, signal transducer and activator of transcription (STAT) signaling activation was involved in the effects of TGF-ß1 on ECM expression in a PRS-dependent manner. This was mediated via a protein-protein complex formation consisting of TGF-ß1 receptor, EPRS, Janus kinases, and STAT6. Additionally, ECM expression in fibrotic livers overlapped with EPRS expression along fibrotic septa regions and was positively correlated with STAT6 activation in carbon tetrachloride-treated mice. This was less obvious in livers of Eprs-/+ mice. These findings suggest that, during fibrosis development, EPRS plays roles in nontranslational processes of ECM expression via intracellular signaling regulation upon TGF-ß1 stimulation.-Song, D.-G., Kim, D., Jung, J. W., Nam, S. H., Kim, J. E., Kim, H.-J., Kim, J. H., Lee, S.-J., Pan, C.-H., Kim, S., Lee, J. W. Glutamyl-prolyl-tRNA synthetase induces fibrotic extracellular matrix via both transcriptional and translational mechanisms.


Asunto(s)
Aminoacil-ARNt Sintetasas/metabolismo , Matriz Extracelular/metabolismo , Biosíntesis de Proteínas/genética , Transcripción Genética/genética , Aminoacil-ARNt Sintetasas/genética , Animales , Línea Celular , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Regulación hacia Abajo/genética , Matriz Extracelular/genética , Fibrosis/genética , Fibrosis/metabolismo , Células Estrelladas Hepáticas/metabolismo , Humanos , Hígado/metabolismo , Cirrosis Hepática/genética , Cirrosis Hepática/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Transducción de Señal/genética , Factor de Crecimiento Transformador beta1/genética , Factor de Crecimiento Transformador beta1/metabolismo , Regulación hacia Arriba/genética
16.
Angew Chem Int Ed Engl ; 59(32): 13379-13384, 2020 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-32368820

RESUMEN

A general strategy for visible-light-enabled site-selective trifluoromethylative pyridylation of unactivated alkenes has been developed using pyridines and triflic anhydride (Tf2 O). Intriguingly, the N-triflylpyridinium salts, generated in situ from pyridines and Tf2 O, serve as effective modular bifunctional reagents to install both CF3 and pyridyl groups to various olefins while controlling C4-selectivity in radical addition to the pyridine core. This synthetic route exhibited broad substrate scope under metal-free and mild photocatalytic conditions, granting efficient access to valuable C4-alkylated pyridines and quinolines without requiring prefunctionalization of the reaction site.

17.
Small ; 14(45): e1802876, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30300469

RESUMEN

Sweat excretion is a dynamic physiological process that varies with body position, activity level, environmental factors, and health status. Conventional means for measuring the properties of sweat yield accurate results but their requirements for sampling and analytics do not allow for use in the field. Emerging wearable devices offer significant advantages over existing approaches, but each has significant drawbacks associated with bulk and weight, inability to quantify volumetric sweat rate and loss, robustness, and/or inadequate accuracy in biochemical analysis. This paper presents a thin, miniaturized, skin-interfaced microfluidic technology that includes a reusable, battery-free electronics module for measuring sweat conductivity and rate in real-time using wireless power from and data communication to electronic devices with capabilities in near field communications (NFC), including most smartphones. The platform exploits ultrathin electrodes integrated within a collection of microchannels as interfaces to circuits that leverage NFC protocols. The resulting capabilities are complementary to those of previously reported colorimetric strategies. Systematic studies of these combined microfluidic/electronic systems, accurate correlations of measurements performed with them to those of laboratory standard instrumentation, and field tests on human subjects exercising and at rest establish the key operational features and their utility in sweat analytics.


Asunto(s)
Electrónica/métodos , Microfluídica/métodos , Animales , Electrólitos/química , Humanos , Piel/química , Sudor/química
18.
Genetica ; 146(2): 211-226, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29441472

RESUMEN

Many peninsulas in the temperate zone played an important role as refugia of various flora and fauna, and the southern Korean Peninsula also served as a refugium for many small mammals in East Asia during the Pleistocene. The Asian lesser white-toothed shrew, Crocidura shantungensis, is a widely distributed species in East Asia, and is an appropriate model organism for exploring the role of the Korean Peninsula as a refugium of small mammals. Here, we investigated phylogenetic relationships and genetic diversity based on the entire sequence of the mitochondrial cytochrome b gene (1140 bp). A Bayesian tree for 98 haplotypes detected in 228 C. shantungensis specimens from East Asia revealed the presence of three major groups with at least 5 subgroups. Most haplotypes were distributed according to their geographic proximity. Pairwise FST's and analysis of molecular variance (AMOVA) revealed a high degree of genetic differentiation and variance among regions as well as among populations within region, implying little gene flow among local populations. Genetic evidence from South Korean islands, Jeju-do Island of South Korea, and Taiwan leads us to reject the hypothesis of recent population expansion. We observed unique island-type genetic characteristics consistent with geographic isolation and resultant genetic drift. Phylogeographic inference, together with estimates of genetic differentiation and diversity, suggest that the southern most part the Korean Peninsula, including offshore islands, played an important role as a refugium for C. shantungensis during the Pleistocene. However, the presence of several refugia on the mainland of northeast Asia is also proposed.


Asunto(s)
Variación Genética , Musarañas/genética , Animales , Citocromos b/genética , Haplotipos , Corea (Geográfico) , Filogeografía , Musarañas/clasificación
19.
Blood ; 120(24): 4892-902, 2012 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-23074279

RESUMEN

In cancer, VEGF-induced increase in vascular permeability results in increased interstitial pressure, reducing perfusion and increasing hypoxia, which reduce delivery of chemotherapeutic agents and increase resistance to ionizing radiation. Here, we show that both TIMP-2 and Ala + TIMP-2, a TIMP-2 mutant without matrix metalloproteinase inhibitory activity, antagonize the VEGF-A-induced increase in vascular permeability, both in vitro and in vivo. Like other agents known to preserve endothelial barrier function, TIMP-2 elevates cytosolic levels of cAMP and increases cytoskeletal-associated vascular endothelial cadherin in human microvascular endothelial cells. All of these effects are completely ablated by selective knockdown of integrin α3ß1 expression, expression of a dominant negative protein tyrosine phosphatase Shp-1 mutant, administration of the protein tyrosine phosphatase inhibitor orthovanadate, or the adenylate cyclase inhibitor SQ22536. This TIMP-2-mediated inhibition of vascular permeability involves an integrin α3ß1-Shp-1-cAMP/protein kinase A-dependent vascular endothelial cadherin cytoskeletal association, as evidenced by using siRNAs to integrin α3ß1 and Shp-1, or treatment with Shp-1 inhibitor NSC87877 and protein kinase A inhibitor H89. Our results demonstrate the potential utility for TIMP-2 in cancer therapy through "normalization" of vascular permeability in addition to previously described antiangiogenic effects.


Asunto(s)
Permeabilidad Capilar/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Inhibidor Tisular de Metaloproteinasa-2/farmacología , Factor A de Crecimiento Endotelial Vascular/farmacología , Adenina/análogos & derivados , Adenina/farmacología , Animales , Antígenos CD/metabolismo , Western Blotting , Cadherinas/metabolismo , Células Cultivadas , AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/antagonistas & inhibidores , Proteínas Quinasas Dependientes de AMP Cíclico/genética , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Citoesqueleto/metabolismo , Antagonismo de Drogas , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Humanos , Integrina alfa3beta1/genética , Integrina alfa3beta1/metabolismo , Isoquinolinas/farmacología , Ratones , Ratones Noqueados , Microscopía Fluorescente , Mutación , Unión Proteica/efectos de los fármacos , Proteína Tirosina Fosfatasa no Receptora Tipo 6/antagonistas & inhibidores , Proteína Tirosina Fosfatasa no Receptora Tipo 6/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Interferencia de ARN , Sulfonamidas/farmacología , Inhibidor Tisular de Metaloproteinasa-2/genética , Vanadatos/farmacología
20.
Bioengineering (Basel) ; 11(1)2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38247961

RESUMEN

Real-time stress distribution data for implants and cortical bones can aid in determining appropriate implant placement plans and improving the post-placement success rate. This study aims to achieve these goals via a parametric reduced-order model (ROM) method based on stress distribution data obtained using finite element analysis. For the first time, the finite element analysis cases for six design variables related to implant placement were determined simultaneously via the design of experiments and a sensitivity analysis. The differences between the minimum and maximum stresses obtained for the six design variables confirm that the order of their influence is: Young's modulus of the cancellous bone > implant thickness > front-rear angle > left-right angle > implant length. Subsequently, a one-dimensional (1-D) CAE solver was created using the ROM with the highest coefficient of determination and prognosis accuracy. The proposed 1-D CAE solver was loaded into the Ondemand3D program and used to implement a digital twin that can aid with dentists' decision making by combining various tooth image data to evaluate and visualize the adequacy of the placement plan in real time. Because the proposed ROM method does not rely entirely on the doctor's judgment, it ensures objectivity.

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