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1.
Cell ; 172(4): 696-705.e12, 2018 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-29398115

RESUMEN

Protein aggregation and dysfunction of the ubiquitin-proteasome system are hallmarks of many neurodegenerative diseases. Here, we address the elusive link between these phenomena by employing cryo-electron tomography to dissect the molecular architecture of protein aggregates within intact neurons at high resolution. We focus on the poly-Gly-Ala (poly-GA) aggregates resulting from aberrant translation of an expanded GGGGCC repeat in C9orf72, the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia. We find that poly-GA aggregates consist of densely packed twisted ribbons that recruit numerous 26S proteasome complexes, while other macromolecules are largely excluded. Proximity to poly-GA ribbons stabilizes a transient substrate-processing conformation of the 26S proteasome, suggesting stalled degradation. Thus, poly-GA aggregates may compromise neuronal proteostasis by driving the accumulation and functional impairment of a large fraction of cellular proteasomes.


Asunto(s)
Alanina/análogos & derivados , Proteína C9orf72 , Neuronas , Ácido Poliglutámico , Complejo de la Endopetidasa Proteasomal , Agregado de Proteínas , Alanina/genética , Alanina/metabolismo , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/metabolismo , Esclerosis Amiotrófica Lateral/patología , Animales , Proteína C9orf72/genética , Proteína C9orf72/metabolismo , Demencia Frontotemporal/genética , Demencia Frontotemporal/metabolismo , Demencia Frontotemporal/patología , Células HEK293 , Humanos , Neuronas/metabolismo , Neuronas/patología , Ácido Poliglutámico/genética , Ácido Poliglutámico/metabolismo , Complejo de la Endopetidasa Proteasomal/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Biosíntesis de Proteínas , Estabilidad Proteica , Estructura Cuaternaria de Proteína , Ratas , Ratas Sprague-Dawley
2.
Annu Rev Biochem ; 86: 193-224, 2017 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-28460188

RESUMEN

Autophagy and the ubiquitin-proteasome system are the two major quality control pathways responsible for cellular homeostasis. As such, they provide protection against age-associated changes and a plethora of human diseases. Ubiquitination is utilized as a degradation signal by both systems, albeit in different ways, to mark cargoes for proteasomal and lysosomal degradation. Both systems intersect and communicate at multiple points to coordinate their actions in proteostasis and organelle homeostasis. This review summarizes molecular details of how proteasome and autophagy pathways are functionally interconnected in cells and indicates common principles and nodes of communication that can be therapeutically exploited.


Asunto(s)
Autofagia/genética , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteína Sequestosoma-1/metabolismo , Ubiquitina/metabolismo , Células Eucariotas/citología , Células Eucariotas/metabolismo , Regulación de la Expresión Génica , Homeostasis , Humanos , Proteína 1 Asociada A ECH Tipo Kelch/química , Proteína 1 Asociada A ECH Tipo Kelch/genética , Mitofagia/genética , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Factor 2 Relacionado con NF-E2/química , Factor 2 Relacionado con NF-E2/genética , Conformación Proteica , Proteolisis , Proteína Sequestosoma-1/química , Proteína Sequestosoma-1/genética , Transducción de Señal , Ubiquitina/genética , Ubiquitinación
3.
Mol Cell ; 83(18): 3333-3346.e5, 2023 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-37738964

RESUMEN

The proteasome is responsible for removal of ubiquitinated proteins. Although several aspects of its regulation (e.g., assembly, composition, and post-translational modifications) have been unraveled, studying its adaptive compartmentalization in response to stress is just starting to emerge. We found that following amino acid starvation, the proteasome is translocated from its large nuclear pool to the cytoplasm-a response regulated by newly identified mTOR-agonistic amino acids-Tyr, Trp, and Phe (YWF). YWF relay their signal upstream of mTOR through Sestrin3 by disrupting its interaction with the GATOR2 complex. The triad activates mTOR toward its downstream substrates p62 and transcription factor EB (TFEB), affecting both proteasomal and autophagic activities. Proteasome translocation stimulates cytosolic proteolysis which replenishes amino acids, thus enabling cell survival. In contrast, nuclear sequestration of the proteasome following mTOR activation by YWF inhibits this proteolytic adaptive mechanism, leading to cell death, which establishes this newly identified pathway as a key stress-coping mechanism.


Asunto(s)
Aminoácidos Aromáticos , Complejo de la Endopetidasa Proteasomal , Supervivencia Celular , Aminoácidos , Serina-Treonina Quinasas TOR/genética
4.
Mol Cell ; 81(16): 3275-3293.e12, 2021 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-34245671

RESUMEN

Cells communicate with their environment via surface proteins and secreted factors. Unconventional protein secretion (UPS) is an evolutionarily conserved process, via which distinct cargo proteins are secreted upon stress. Most UPS types depend upon the Golgi-associated GRASP55 protein. However, its regulation and biological role remain poorly understood. Here, we show that the mechanistic target of rapamycin complex 1 (mTORC1) directly phosphorylates GRASP55 to maintain its Golgi localization, thus revealing a physiological role for mTORC1 at this organelle. Stimuli that inhibit mTORC1 cause GRASP55 dephosphorylation and relocalization to UPS compartments. Through multiple, unbiased, proteomic analyses, we identify numerous cargoes that follow this unconventional secretory route to reshape the cellular secretome and surfactome. Using MMP2 secretion as a proxy for UPS, we provide important insights on its regulation and physiological role. Collectively, our findings reveal the mTORC1-GRASP55 signaling hub as the integration point in stress signaling upstream of UPS and as a key coordinator of the cellular adaptation to stress.


Asunto(s)
Proteínas de la Matriz de Golgi/genética , Proteoma/genética , Proteómica , Estrés Fisiológico/genética , Matriz Extracelular/genética , Aparato de Golgi/genética , Humanos , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Proteínas de la Membrana/genética , Transporte de Proteínas/genética , Transducción de Señal/genética
5.
Trends Biochem Sci ; 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38945729

RESUMEN

The degradation of damaged proteins is critical for tissue integrity and organismal health because damaged proteins have a high propensity to form aggregates. E3 ubiquitin ligases are key regulators of protein quality control (PQC) and mediate the selective degradation of damaged proteins, a process termed 'PQC degradation' (PQCD). The degradation signals (degrons) that trigger PQCD are based on hydrophobic sites that are normally buried within the native protein structure. However, an open question is how PQCD-specialized E3 ligases distinguish between transiently misfolded proteins, which can be efficiently refolded, and permanently damaged proteins, which must be degraded. While significant progress has been made in characterizing degradation determinants, understanding the key regulatory signals of cellular and organismal PQCD pathways remains a challenge.

6.
Immunity ; 51(3): 522-534.e7, 2019 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-31471107

RESUMEN

Although recent progress provides mechanistic insights into the pathogenesis of pulmonary fibrosis (PF), rare anti-PF therapeutics show definitive promise for treating this disease. Repeated lung epithelial injury results in injury-repairing response and inflammation, which drive the development of PF. Here, we report that chronic lung injury inactivated the ubiquitin-editing enzyme A20, causing progressive accumulation of the transcription factor C/EBPß in alveolar macrophages (AMs) from PF patients and mice, which upregulated a number of immunosuppressive and profibrotic factors promoting PF development. In response to chronic lung injury, elevated glycogen synthase kinase-3ß (GSK-3ß) interacted with and phosphorylated A20 to suppress C/EBPß degradation. Ectopic expression of A20 or pharmacological restoration of A20 activity by disturbing the A20-GSK-3ß interaction accelerated C/EBPß degradation and showed potent therapeutic efficacy against experimental PF. Our study indicates that a regulatory mechanism of the GSK-3ß-A20-C/EBPß axis in AMs may be a potential target for treating PF and fibroproliferative lung diseases.


Asunto(s)
Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Macrófagos/metabolismo , Fibrosis Pulmonar/metabolismo , Factores de Transcripción/metabolismo , Ubiquitina/metabolismo , Animales , Línea Celular , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Células HEK293 , Humanos , Inflamación/metabolismo , Ratones , Ratones Endogámicos C57BL , Fosforilación/fisiología , Transducción de Señal/fisiología , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación/fisiología , Regulación hacia Arriba/fisiología
7.
Trends Biochem Sci ; 47(8): 699-709, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35490075

RESUMEN

In recent years, a surprisingly complex picture emerged about endoplasmic reticulum (ER)/Golgi-independent secretory pathways, and several routes have been discovered that differ with regard to their molecular mechanisms and machineries. Fibroblast growth factor 2 (FGF2) is secreted by a pathway of unconventional protein secretion (UPS) that is based on direct self-translocation across the plasma membrane. Building on previous research, a component of this process has been identified to be glypican-1 (GPC1), a GPI-anchored heparan sulfate proteoglycan located on cell surfaces. These findings not only shed light on the molecular mechanism underlying this process but also reveal an intimate relationship between FGF2 and GPC1 that might be of critical relevance for the prominent roles they both have in tumor progression and metastasis.


Asunto(s)
Factor 2 de Crecimiento de Fibroblastos , Aparato de Golgi , Animales , Transporte Biológico , Membrana Celular/metabolismo , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Aparato de Golgi/metabolismo , Mamíferos , Transporte de Proteínas
8.
Mol Cell ; 70(5): 906-919.e7, 2018 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-29804830

RESUMEN

Stress granules (SGs) are cytoplasmic assemblies of mRNPs stalled in translation initiation. They are induced by various stress conditions, including exposure to the environmental toxin and carcinogen arsenic. While perturbed SG turnover is linked to the pathogenesis of neurodegenerative diseases, the molecular mechanisms underlying SG formation and turnover are still poorly understood. Here, we show that ZFAND1 is an evolutionarily conserved regulator of SG clearance. ZFAND1 interacts with two key factors of protein degradation, the 26S proteasome and the ubiquitin-selective segregase p97, and recruits them to arsenite-induced SGs. In the absence of ZFAND1, SGs lack the 26S proteasome and p97, accumulate defective ribosomal products, and persist after arsenite removal, indicating their transformation into aberrant, disease-linked SGs. Accordingly, ZFAND1 depletion is epistatic to the expression of pathogenic mutant p97 with respect to SG clearance, suggesting that ZFAND1 function is relevant to the multisystem degenerative disorder IBMPFD/ALS.


Asunto(s)
Arsenitos/toxicidad , Gránulos Citoplasmáticos/efectos de los fármacos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Compuestos de Sodio/toxicidad , Estrés Fisiológico , Factor 2 Asociado a Receptor de TNF/metabolismo , Autofagia/efectos de los fármacos , Gránulos Citoplasmáticos/enzimología , Gránulos Citoplasmáticos/patología , Células HEK293 , Células HeLa , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Complejo de la Endopetidasa Proteasomal/genética , Transporte de Proteínas , Proteolisis , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/enzimología , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Transducción de Señal/efectos de los fármacos , Factor 2 Asociado a Receptor de TNF/genética
9.
Mol Cell Proteomics ; 23(7): 100791, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38797438

RESUMEN

Within a cell, proteins have distinct and highly variable half-lives. As a result, the molecular ages of proteins can range from seconds to years. How the age of a protein influences its environmental interactions is a largely unexplored area of biology. To investigate the age-selectivity of cellular pathways, we developed a methodology termed "proteome birthdating" that barcodes proteins based on their time of synthesis. We demonstrate that this approach provides accurate measurements of protein turnover kinetics from a single biological sample encoding multiple labeling time-points. As a first application of the birthdated proteome, we investigated the age distribution of the human ubiquitinome. Our results indicate that the vast majority of ubiquitinated proteins in a cell consist of newly synthesized proteins and that these young proteins constitute the bulk of the degradative flux through the proteasome. Rapidly ubiquitinated nascent proteins are enriched in cytosolic subunits of large protein complexes. Conversely, proteins destined for the secretory pathway and vesicular transport have older ubiquitinated populations. Our data also identify a smaller subset of older ubiquitinated cellular proteins that do not appear to be targeted to the proteasome for rapid degradation. Together, our data provide an age census of the human ubiquitinome and establish proteome birthdating as a robust methodology for investigating the protein age-selectivity of diverse cellular pathways.


Asunto(s)
Complejo de la Endopetidasa Proteasomal , Proteoma , Proteínas Ubiquitinadas , Ubiquitinación , Humanos , Proteoma/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas Ubiquitinadas/metabolismo , Proteómica/métodos , Proteolisis , Ubiquitina/metabolismo
10.
Am J Hum Genet ; 109(2): 361-372, 2022 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-35051358

RESUMEN

Nuclear deubiquitinase BAP1 (BRCA1-associated protein 1) is a core component of multiprotein complexes that promote transcription by reversing the ubiquitination of histone 2A (H2A). BAP1 is a tumor suppressor whose germline loss-of-function variants predispose to cancer. To our knowledge, there are very rare examples of different germline variants in the same gene causing either a neurodevelopmental disorder (NDD) or a tumor predisposition syndrome. Here, we report a series of 11 de novo germline heterozygous missense BAP1 variants associated with a rare syndromic NDD. Functional analysis showed that most of the variants cannot rescue the consequences of BAP1 inactivation, suggesting a loss-of-function mechanism. In T cells isolated from two affected children, H2A deubiquitination was impaired. In matching peripheral blood mononuclear cells, histone H3 K27 acetylation ChIP-seq indicated that these BAP1 variants induced genome-wide chromatin state alterations, with enrichment for regulatory regions surrounding genes of the ubiquitin-proteasome system (UPS). Altogether, these results define a clinical syndrome caused by rare germline missense BAP1 variants that alter chromatin remodeling through abnormal histone ubiquitination and lead to transcriptional dysregulation of developmental genes.


Asunto(s)
Proteína BRCA1/genética , Mutación de Línea Germinal , Mutación con Pérdida de Función , Mutación Missense , Trastornos del Neurodesarrollo/genética , Proteínas Supresoras de Tumor/genética , Ubiquitina Tiolesterasa/genética , Adolescente , Proteína BRCA1/inmunología , Niño , Preescolar , Cromatina/química , Cromatina/inmunología , Ensamble y Desensamble de Cromatina/genética , Ensamble y Desensamble de Cromatina/inmunología , Familia , Femenino , Regulación de la Expresión Génica , Heterocigoto , Histonas/genética , Histonas/inmunología , Factor C1 de la Célula Huésped/genética , Factor C1 de la Célula Huésped/inmunología , Humanos , Lactante , Masculino , Trastornos del Neurodesarrollo/inmunología , Trastornos del Neurodesarrollo/patología , Complejo de la Endopetidasa Proteasomal/genética , Complejo de la Endopetidasa Proteasomal/inmunología , Linfocitos T/inmunología , Linfocitos T/patología , Proteínas Supresoras de Tumor/deficiencia , Proteínas Supresoras de Tumor/inmunología , Ubiquitina/genética , Ubiquitina/inmunología , Ubiquitina Tiolesterasa/deficiencia , Ubiquitina Tiolesterasa/inmunología , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/inmunología , Ubiquitinación
11.
J Biol Chem ; 299(2): 102851, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36587767

RESUMEN

Misfolded proteins are recognized and degraded through protein quality control (PQC) pathways, which are essential for maintaining proteostasis and normal cellular functions. Defects in PQC can result in disease, including cancer, cardiovascular disease, and neurodegeneration. The small ubiquitin-related modifiers (SUMOs) were previously implicated in the degradation of nuclear misfolded proteins, but their functions in cytoplasmic PQC are unclear. Here, in a systematic screen of SUMO protein mutations in the budding yeast Saccharomyces cerevisiae, we identified a mutant allele (Smt3-K38A/K40A) that sensitizes cells to proteotoxic stress induced by amino acid analogs. Smt3-K38A/K40A mutant strains also exhibited a defect in the turnover of a soluble PQC model substrate containing the CL1 degron (NES-GFP-Ura3-CL1) localized in the cytoplasm, but not the nucleus. Using human U2OS SUMO1- and SUMO2-KO cell lines, we observed a similar SUMO-dependent pathway for degradation of the mammalian degron-containing PQC reporter protein, GFP-CL1, also only in the cytoplasm but not the nucleus. Moreover, we found that turnover of GFP-CL1 in the cytoplasm was uniquely dependent on SUMO1 but not the SUMO2 paralogue. Additionally, we showed that turnover of GFP-CL1 in the cytoplasm is dependent on the AAA-ATPase, Cdc48/p97. Cellular fractionation studies and analysis of a SUMO1-GFP-CL1 fusion protein revealed that SUMO1 promotes cytoplasmic misfolded protein degradation by maintaining substrate solubility. Collectively, our findings reveal a conserved and previously unrecognized role for SUMO1 in regulating cytoplasmic PQC and provide valuable insights into the roles of sumoylation in PQC-associated diseases.


Asunto(s)
Proteolisis , Proteína SUMO-1 , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Animales , Humanos , Citoplasma/metabolismo , Citosol/metabolismo , Proteínas Nucleares/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteína SUMO-1/genética , Proteína SUMO-1/metabolismo
12.
Plant Cell Physiol ; 65(3): 390-404, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38153765

RESUMEN

Mitogen-activated protein kinase (MAPK) cascades are conserved signaling pathways that transduce extracellular signals into diverse cellular responses. Arabidopsis MAPKKK18 is a component of the MAPKKK17/18-MKK3-MPK1/2/7/14 cascades, which play critical roles in abscisic acid (ABA) signaling, drought tolerance and senescence. A very important aspect of MAP kinase signaling is both its activation and its termination, which must be tightly controlled to achieve appropriate biological responses. Recently, the ubiquitin-proteasome system (UPS) has received increasing attention as a key mechanism for maintaining the homeostasis of MAPK cascade components and other ABA signaling effectors. Previous studies have shown that the stability of MAPKKK18 is regulated by the UPS via the ABA core pathway. Here, using multiple proteomic approaches, we found that MAPKKK17/18 turnover is tightly controlled by three E3 ligases, UPL1, UPL4 and KEG. We also identified lysines 154 and 237 as critical for MAPKKK18 stability. Taken together, this study sheds new light on the mechanism that controls MAPKKK17/18 activity and function.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteómica , Complejo de la Endopetidasa Proteasomal/metabolismo , Ubiquitina/metabolismo , Quinasas Quinasa Quinasa PAM/metabolismo
13.
J Gene Med ; 26(1): e3584, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37605934

RESUMEN

BACKGROUND: Triple-negative breast cancer (TNBC) is a pathological subtype with a high mortality, and the development of inhibitors in the ubiquitin-proteasome system (UPS) component could be a novel therapeutic tool. METHODS: Triple-negative breast cancer data were obtained from The Cancer Genome Atlas (TCGA), and subtype analysis was performed by consistent clustering analysis to identify molecular subtypes of TNBC according to UPS characteristics. Differential analysis, COX and least absolute shrinkage and selection operator (LASSO) COX regression analyses were performed to select genes associated with overall survival in TNBC. The final prognostic model (UPS score) was determined using the LASSO COX model. The model performance was assessed using receiver operating characteristic (ROC) curves and survival curves. In addition, the results of the UPS score on analyzing the abundance of immune cell infiltration and immunotherapy were explored. Finally, we developed a nomogram for TNBC survival prediction. RESULTS: Two UPS subtypes (UPSMS1 and UPSMS2) showing significant survival differences were classified. COX regression analysis on differentially expressed genes in UPSMS1 and UPSMS2 filtered five genes that affected overall survival. Based on the regression coefficients and expression data of the five genes, we built a prognostic assessment system (UPS score). The UPS score showed consistent prognostic and therapeutic guidance values. Finally, the ROC curve of the nomogram and UPS score showed the highest predictive efficacy compared with traditional clinical prognostic indicators. CONCLUSION: The UPS score represented a promising prognostic tool to predict overall survival and immune status and guide personalized treatment selection in TNBC patients, and this study may provide a more practical alternative for clinical monitoring and management of TNBC.


Asunto(s)
Complejo de la Endopetidasa Proteasomal , Neoplasias de la Mama Triple Negativas , Humanos , Complejo de la Endopetidasa Proteasomal/genética , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/terapia , Citoplasma , Inmunoterapia , Ubiquitinas
14.
Magn Reson Med ; 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39054786

RESUMEN

PURPOSE: T 2 $$ {}_2 $$ -weighted turbo-spin-echo (TSE) sequences are a fundamental technique in brain imaging but suffer from field inhomogeneities at ultra-high fields. Several methods have been proposed to mitigate the problem, but were limited so far to nonselective three-dimensional (3D) measurements, making short acquisitions difficult to achieve when targeting very high resolution images, or needed additional calibration procedures, thus complicating their application. METHODS: Slab-selective excitation pulses were designed for flexible placement utilizing the concept of k T $$ {}_T $$ -spokes. Phase-coherent refocusing universal pulses were subsequently optimized with the Gradient Ascent Pulse Engineering algorithm and tested in vivo for improved signal homogeneity. RESULTS: Implemented within a 3D variable flip angle TSE sequence, these pulses led to a signal-to-noise ratio (SNR) improvement ranging from 10% to 30% compared to a two-dimensional (2D) T2w TSE sequence employing B 1 + $$ {\mathrm{B}}_1^{+} $$ -shimmed pulses. B 1 + $$ {\mathrm{B}}_1^{+} $$ field inhomogeneities could be mitigated and artifacts from B 0 $$ {\mathrm{B}}_0 $$ deviations reduced. The concept of universal pulses was successfully applied. CONCLUSION: We present a pulse design method which provides a set of calibration-free universal pulses (UPs) for slab-selective excitation and phase-coherent refocusing in slab-selective TSE sequences.

15.
Exp Brain Res ; 242(4): 971-986, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38430248

RESUMEN

The gradual nature of age-related neurodegeneration causes Parkinson's disease (PD) and impairs movement, memory, intellectual ability, and social interaction. One of the most prevalent neurodegenerative conditions affecting the central nervous system (CNS) among the elderly is PD. PD affects both motor and cognitive functions. Degeneration of dopaminergic (DA) neurons and buildup of the protein α-synuclein (α-Syn) in the substantia nigra pars compacta (SNpc) are two major causes of this disorder. Both UPS and ALS systems serve to eliminate α-Syn. Autophagy and UPS deficits, shortened life duration, and lipofuscin buildup accelerate PD. This sickness has no cure. Innovative therapies are halting PD progression. Bioactive phytochemicals may provide older individuals with a natural substitute to help delay the onset of neurodegenerative illnesses. This study examines whether nicotine helps transgenic C. elegans PD models. According to numerous studies, nicotine enhances synaptic plasticity and dopaminergic neuronal survival. Upgrades UPS pathways, increases autophagy, and decreases oxidative stress and mitochondrial dysfunction. At 100, 150, and 200 µM nicotine levels, worms showed reduced α-Syn aggregation, repaired DA neurotoxicity after 6-OHDA intoxication, increased lifetime, and reduced lipofuscin accumulation. Furthermore, nicotine triggered autophagy and UPS. We revealed nicotine's potential as a UPS and autophagy activator to prevent PD and other neurodegenerative diseases.


Asunto(s)
Enfermedades Neurodegenerativas , Enfermedad de Parkinson , Animales , Humanos , Anciano , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/metabolismo , Nicotina/farmacología , Nicotina/metabolismo , Caenorhabditis elegans/metabolismo , Lipofuscina/metabolismo , Lipofuscina/farmacología , alfa-Sinucleína/metabolismo , alfa-Sinucleína/farmacología , Enfermedades Neurodegenerativas/metabolismo , Neuronas Dopaminérgicas/metabolismo , Autofagia
16.
Cell Mol Life Sci ; 80(4): 106, 2023 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-36952018

RESUMEN

Ubiquitin carboxyl-terminal hydrolase L1 (UCHL1) is a unique component of the ubiquitin-proteasome system (UPS), which has multiple activities in maintaining intracellular ubiquitin levels. We previously reported the aberrant low expression of UCHL1 in podocytes of non-immune complex-mediated glomerulonephritis, and recent studies indicate that anti-UCHL1 antibody was responsible for the refractory minimal change disease (MCD), but the specific effect of UCHL1 to the podocytopathy has not been determined. Therefore, we generated podocyte-specific UCHL1 gene knockout (UCHL1cre/cre) rats model. Podocyte-specific UCHL1 knockout rats exhibited severe kidney damage, including segmental/global glomerulosclerosis, kidney function damage and severe proteinuria, compared with littermate control. Subsequently, by carrying out mass spectrometry analysis of isolated glomeruli of rats, abnormal protein accumulation of ECM-receptor Interaction was found in UCHL1cre/cre rats. Mechanistic studies in vivo and in vitro revealed that aberrant protein accumulation after UCHL1 deficiency induced endoplasmic reticulum (ER) stress, unfolded protein reaction (UPR) to reduce the protein level of podocyte skeleton proteins, and CHOP mediated apoptosis as well, which related to the dysfunction of the ubiquitin-proteasome system with decreased free monomeric ubiquitin level, thereby affecting protein ubiquitination and degradation. In addition, inhibition of ER stress by 4-PBA could attenuate the degree of ER stress and podocyte dysfunction. Our study indicates that UCHL1 is a potential target for preventing podocytes injury in some non-immune complex-mediated glomerulopathy.


Asunto(s)
Enfermedades Renales , Podocitos , Ratas , Animales , Podocitos/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Ubiquitina/metabolismo , Ubiquitinación , Estrés del Retículo Endoplásmico/genética , Enfermedades Renales/metabolismo , Ubiquitina Tiolesterasa/metabolismo
17.
BMC Public Health ; 24(1): 1999, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39061022

RESUMEN

BACKGROUND: As multimorbidity becomes common that imposes a considerable burden to patients, but the extent to which widely-used multimorbidity indexes can be applied to quantify disease burden using primary care data in China is not clear. We applied the Chinese Multimorbidity-Weighted Index (CMWI) to health check-ups data routinely collected among older adults by primary care, to examine its validity in measuring multimorbidity associated risks of disability and mortality in annual follow-ups. METHODS: The study utilized data from annual health check-ups of older adults, which included information on individual age, sex, and 14 health conditions at primary care in a district of Guangzhou, Guangdong, China. The risk of CMWI for mortality was analysed in a total sample of 45,009 persons 65 years and older between 2014 and 2020 (average 2.70-year follow-up), and the risk for disability was in a subsample of 18,320 older adults free of physical impairment in 2019 and followed-up in 2020. Risk of death and disability were assessed with Cox proportional hazard regression and binary logistic regression, respectively, with both models adjusted for age and sex variables. The model fit was assessed by the Akaike information criterion (AIC), and C-statistic or the area under the receiver operating characteristic curve (AUC). RESULTS: One unit increase in baseline-CMWI (Median= 1.70, IQR: 1.30-3.00) was associated with higher risk in subsequent disability (OR = 1.12, 95%CI = 1.05,1.20) and mortality (OR = 1.18, 95%CI = 1.14, 1.22). Participants in the top tertile of CMWI had 99% and 152% increased risks of disability and mortality than their counterparts in the bottom tertile. Model fit was satisfied with adequate AUC (0.84) or C-statistic (0.76) for both outcomes. CONCLUSIONS: CMWI, calculated based on primary care's routine health check-ups data, provides valid estimates of disability and mortality risks in older adults. This validated tool can be used to quantity and monitor older patients' health risks in primary care.


Asunto(s)
Multimorbilidad , Atención Primaria de Salud , Humanos , Masculino , Femenino , Anciano , Atención Primaria de Salud/estadística & datos numéricos , China/epidemiología , Anciano de 80 o más Años , Costo de Enfermedad , Reproducibilidad de los Resultados , Examen Físico , Pueblos del Este de Asia
18.
Mikrochim Acta ; 191(4): 184, 2024 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-38451295

RESUMEN

The three decades of experience with piezoelectric devices applied in the field of bioanalytical chemistry are shared. After introduction to principles and suitable measuring approaches, active and passive methods based on oscillators and impedance analysis, respectively, the focus is directed towards biosensing approaches. Immunosensing examples are provided, followed by other affinity sensing approaches based on hybridization of nucleic acids, aptamers, monitoring of enzyme activities, and detection of pathogenic microbes. The combination of piezosensors with cell lines and testing of drugs is highlighted, including mechanically active cells. The combination of piezosensors with other measuring techniques providing original hybrid devices is briefly discussed.


Asunto(s)
Ácidos Nucleicos , Línea Celular , Impedancia Eléctrica , Oligonucleótidos
19.
J Allergy Clin Immunol ; 152(6): 1493-1519, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37678572

RESUMEN

BACKGROUND: Atopic dermatitis (AD) is a common skin condition with multiple topical treatment options, but uncertain comparative effects. OBJECTIVE: We sought to systematically synthesize the benefits and harms of AD prescription topical treatments. METHODS: For the 2023 American Academy of Allergy, Asthma & Immunology and American College of Allergy, Asthma, and Immunology Joint Task Force on Practice Parameters AD guidelines, we searched MEDLINE, EMBASE, CENTRAL, CINAHL, LILACS, ICTRP, and GREAT databases to September 5, 2022, for randomized trials addressing AD topical treatments. Paired reviewers independently screened records, extracted data, and assessed risk of bias. Random-effects network meta-analyses addressed AD severity, itch, sleep, AD-related quality of life, flares, and harms. The Grading of Recommendations Assessment, Development and Evaluation approach informed certainty of evidence ratings. We classified topical corticosteroids (TCS) using 7 groups-group 1 being most potent. This review is registered in the Open Science Framework (https://osf.io/q5m6s). RESULTS: The 219 included trials (43,123 patients) evaluated 68 interventions. With high-certainty evidence, pimecrolimus improved 6 of 7 outcomes-among the best for 2; high-dose tacrolimus (0.1%) improved 5-among the best for 2; low-dose tacrolimus (0.03%) improved 5-among the best for 1. With moderate- to high-certainty evidence, group 5 TCS improved 6-among the best for 3; group 4 TCS and delgocitinib improved 4-among the best for 2; ruxolitinib improved 4-among the best for 1; group 1 TCS improved 3-among the best for 2. These interventions did not increase harm. Crisaborole and difamilast were intermediately effective, but with uncertain harm. Topical antibiotics alone or in combination may be among the least effective. To maintain AD control, group 5 TCS were among the most effective, followed by tacrolimus and pimecrolimus. CONCLUSIONS: For individuals with AD, pimecrolimus, tacrolimus, and moderate-potency TCS are among the most effective in improving and maintaining multiple AD outcomes. Topical antibiotics may be among the least effective.


Asunto(s)
Asma , Dermatitis Atópica , Fármacos Dermatológicos , Eccema , Humanos , Dermatitis Atópica/tratamiento farmacológico , Tacrolimus/uso terapéutico , Metaanálisis en Red , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Fármacos Dermatológicos/uso terapéutico , Asma/tratamiento farmacológico , Antibacterianos/uso terapéutico
20.
Odontology ; 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38805093

RESUMEN

The objectives of this online study were to determine the status of regular dental check-ups among Thai nationals living in Japan and to identify barriers to regular dental check-ups by comparing them with general health check-ups. We conducted the online survey twice, in 2021 and 2022, among Thai nationals aged 18 years and older living in Japan via social networking services by an organization that supports Thai nationals living in Japan. Respondents between the ages of 30 and 59 were included in this study. Independent factors included gender, age, length of stay in Japan, family economic status, confidence in Japanese and stay for work purposes. Dependent factors were regular dental check-ups and general health check-ups in the past year. Chi-square tests and multiple logistic regression analyses were used for analysis. 56.6% of respondents had regular dental check-ups. The adjusted odds ratio for the proportion of people with regular dental check-ups was significantly higher for those with high economic status, 2.15 (1.06-4.33), compared with those with low economic status. It was also significantly higher 1.88 (1.10-3.21) for those with confidence in the Japanese language compared with those without. The study suggested the need for Japanese language support in addition to financial support for dental health prevention programs for foreigners living in Japan.

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