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1.
Eval Program Plann ; 99: 102320, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37257359

RESUMO

The declining birth rate, population ageing and the outbound migration of young people in recent years have created obstacles for local companies in recruiting skilled personnel. Similar factors have also affected recruitment in the outlying island of Penghu, Taiwan. Multiple-attribute decision-making (MADM) techniques for evaluation model development were incorporated in the present research to investigate the key determinants of talent recruitment by the coffee house operators in the outlying island of Penghu. The decision-making trial and evaluation laboratory (DEMATEL) approach was first implemented to (i) examine the extent of mutual impact between evaluation predictors and (ii) develop an influential network relation map (NRM) for indicator and sub-indicator assessments. Subsequently, the DEMATEL-based analytic network process (DANP) technique was utilised to compute the weights of every indicator and sub-indicator. Additionally, the modified VlseKriterijumska Optimizcija I Kaompromisno Resenje or VIKOR (in Serbian) approach evaluated every indicator and sub-indicator performance gap for empirical data analysis with suggested conclusions and recommendations. The results showed that the first dimension that should be improved is past experience, followed by personality traits and professional competence, according to the causal diagram of the NRM. The weights acquired through the DANP indicated that professional competence was the most influential dimension, followed by personality traits, whereas past experience was the least influential. Past experience revealed that the highest gap value is the most important for development if coffee house operators want to attain the appropriate levels. Finally, the theoretical, managerial, and practical implications were discussed. Notably, the research outcomes could optimise talent recruitment, establish appropriate talent recruitment methods for coffee house operators, and enhance the human resource quality in the outlying island of Penghu.


Assuntos
Café , Competência Profissional , Humanos , Adolescente , Taiwan , Avaliação de Programas e Projetos de Saúde
2.
bioRxiv ; 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38168389

RESUMO

Tauopathies are a class of neurodegenerative diseases characterized by the progressive misfolding and accumulation of pathological tau protein in focal regions of the brain, leading to insidious neurodegeneration. Abnormalities in cholesterol metabolism and homeostasis have also been implicated in various neurodegenerative diseases. However, the connection between cholesterol dysregulation and tau pathology remains largely unknown. To model and measure the impact of cholesterol dysregulation on tau, we utilized a combination of in vitro and ex vivo tau aggregation assays using an engineered tau biosensor cell line and human induced pluripotent stem cell (iPSC)-derived neuronal cultures from an individual harboring an autosomal dominant P301L tau mutation and from a healthy control. We demonstrate that excess cholesterol esters lead to an increased rate of tau aggregation in vitro and an increase in seed-dependent insoluble tau aggregates detected in the biosensor line. We observed a strong correlation between cholesterol ester concentration and the presence of high-molecular-weight, oligomeric tau species. Importantly, in tauopathy patient iPSC-derived neurons harboring a P301L tau mutation with endogenous forms of misfolded tau, we show that acute dysregulation of cholesterol homeostasis through acute exposure to human plasma-purified cholesterol esters formed by the linkage of fatty acids to the hydroxyl group of cholesterol leads to the rapid accumulation of phosphorylated tau. Conversely, treatment with the same cholesterol esters pool did not lead to subsequent accumulation of phosphorylated tau in control iPSC-derived neurons. Finally, treatment with a heterobifunctional, small-molecule degrader designed to selectively engage and catalyze the ubiquitination and proteasomal degradation of aberrant tau species prevented cholesterol ester-induced aggregation of tau in the biosensor cell line in a Cereblon E3 ligase-dependent manner. Degrader treatment also restored the resiliency of tauopathy patient-derived neurons towards cholesterol ester-induced tau aggregation phenotypes. Taken together, our study supports a key role of cholesterol dysregulation in tau aggregation. Moreover, it provides further pre-clinical validation of the therapeutic strategy of targeted protein degradation with heterobifunctional tau degraders for blocking tau seeding.

3.
Int J Med Mushrooms ; 24(12): 57-67, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36374982

RESUMO

Dry eye disease (DED), a multifactorial inflammatory ocular surface disorder, affects up to 50% of individuals over 50 years old worldwide and is one of the most common reasons for seeking ophthalmologic care. Generally, topical eye drops or oral drugs are administered to treat DED; however, the use of preservatives in eye drops or the adverse effects of oral drugs are disadvantageous for long-term therapy. Cordyceps cicadae, a traditional Chinese medicinal fungus, possesses anti-inflammatory effects without evident toxicity and is obtainable at low price. Our previous study demonstrated that C. cicadae mycelium effectively ameliorates dry eye symptoms in the benzalkonium chloride (BAC)-induced mouse dry eye model by increasing tear volume and tear film breakup time (TBUT). However, the effects of C. cicadae mycelium for human dry eye amelioration remains unknown. Thus, the present study investigated the mitigation of dry eye conditions and related discomforts through oral supplementation of fermented C. cicadae mycelium. A total of 70 healthy individuals were recruited and randomly allocated to receive a daily oral dose of 1,050 mg preparation in sachet containing either freeze-dried C. cicadae mycelium powder with 0.3 mg of adenosine and 1.5 mg of HEA per gram or placebo for 90 days. The participants were subjected to anthropometric measurements, dry eye questionnaires (DEQ), Schirmer's tests, intraocular pressure (IOP) measurements, tear film breakup time (TBUT) tests, tear osmolality measurements, and tear electrolyte analysis prior to and right after completion of the study. The results showed a significantly increased TBUT as well as a significant decrease in tear osmolarity, in parallel with the decrease of tear electrolytes, especially Na+ and Cl ions. Although significant increase of tear volume was not observed, the increased TBUT suggests mitigation of dry eye through improvement of tear quality. Therefore, C. cicadae mycelium supplementation may be used for dry eye alleviation as a novel therapeutic intervention.


Assuntos
Cordyceps , Síndromes do Olho Seco , Humanos , Animais , Camundongos , Pessoa de Meia-Idade , Projetos Piloto , Síndromes do Olho Seco/tratamento farmacológico , Síndromes do Olho Seco/diagnóstico , Soluções Oftálmicas/uso terapêutico , Micélio , Suplementos Nutricionais
4.
J Med Chem ; 64(19): 14809-14821, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34606726

RESUMO

The protein homeostasis (proteostasis) network is composed of multiple pathways that work together to balance protein folding, stability, and turnover. Cancer cells are particularly reliant on this network; however, it is hypothesized that inhibition of one node might lead to compensation. To better understand these connections, we dosed 22Rv1 prostate cancer cells with inhibitors of four proteostasis targets (Hsp70, Hsp90, proteasome, and p97), either alone or in binary combinations, and measured the effects on cell growth. The results reveal a series of additive, synergistic, and antagonistic relationships, including strong synergy between inhibitors of p97 and the proteasome and striking antagonism between inhibitors of Hsp90 and the proteasome. Based on RNA-seq, these relationships are associated, in part, with activation of stress pathways. Together, these results suggest that cocktails of proteostasis inhibitors might be a powerful way of treating some cancers, although antagonism that blunts the efficacy of both molecules is also possible.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Próstata/patologia , Proteostase/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Proteínas de Choque Térmico HSP70 , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Masculino , Complexo de Endopeptidases do Proteassoma/metabolismo , Receptores Androgênicos/metabolismo , Análise de Sequência de RNA , Estresse Fisiológico
5.
Nat Commun ; 12(1): 2238, 2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33854069

RESUMO

Disrupted homeostasis of the microtubule binding protein tau is a shared feature of a set of neurodegenerative disorders known as tauopathies. Acetylation of soluble tau is an early pathological event in neurodegeneration. In this work, we find that a large fraction of neuronal tau is degraded by chaperone-mediated autophagy (CMA) whereas, upon acetylation, tau is preferentially degraded by macroautophagy and endosomal microautophagy. Rerouting of acetylated tau to these other autophagic pathways originates, in part, from the inhibitory effect that acetylated tau exerts on CMA and results in its extracellular release. In fact, experimental blockage of CMA enhances cell-to-cell propagation of pathogenic tau in a mouse model of tauopathy. Furthermore, analysis of lysosomes isolated from brains of patients with tauopathies demonstrates similar molecular mechanisms leading to CMA dysfunction. This study reveals that CMA failure in tauopathy brains alters tau homeostasis and could contribute to aggravate disease progression.


Assuntos
Autofagia Mediada por Chaperonas , Tauopatias/metabolismo , Proteínas tau/metabolismo , Acetilação , Animais , Encéfalo/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/metabolismo , Tauopatias/genética , Tauopatias/patologia , Tauopatias/fisiopatologia , Proteínas tau/genética
6.
Cell Chem Biol ; 27(3): 292-305.e6, 2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-32017918

RESUMO

Hsp90 plays an important role in health and is a therapeutic target for managing misfolding disease. Compounds that disrupt co-chaperone delivery of clients to Hsp90 target a subset of Hsp90 activities, thereby minimizing the toxicity of pan-Hsp90 inhibitors. Here, we have identified SEW04784 as a first-in-class inhibitor of the Aha1-stimulated Hsp90 ATPase activity without inhibiting basal Hsp90 ATPase. Nuclear magnetic resonance analysis reveals that SEW84 binds to the C-terminal domain of Aha1 to weaken its asymmetric binding to Hsp90. Consistent with this observation, SEW84 blocks Aha1-dependent Hsp90 chaperoning activities, including the in vitro and in vivo refolding of firefly luciferase, and the transcriptional activity of the androgen receptor in cell-based models of prostate cancer and promotes the clearance of phosphorylated tau in cellular and tissue models of neurodegenerative tauopathy. We propose that SEW84 provides a novel lead scaffold for developing therapeutic approaches to treat proteostatic disease.


Assuntos
Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Chaperonas Moleculares/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Células HEK293 , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Chaperonas Moleculares/metabolismo , Estrutura Molecular , Dobramento de Proteína/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química
7.
Chem Sci ; 11(7): 1892-1904, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34123282

RESUMO

Understanding the selectivity of a small molecule for its target(s) in cells is an important goal in chemical biology and drug discovery. One powerful way to address this question is with dominant negative (DN) mutants, in which an active site residue in the putative target is mutated. While powerful, this approach is less straightforward for allosteric sites. Here, we introduce tryptophan scanning mutagenesis as an expansion of this idea. As a test case, we focused on the challenging drug target, heat shock cognate protein 70 (Hsc70), and its allosteric inhibitor JG-98. Structure-based modelling predicted that mutating Y149W in human Hsc70 or Y145W in the bacterial ortholog DnaK would place an indole side chain into the allosteric pocket normally occupied by the compound. Indeed, we found that the tryptophan mutants acted as if they were engaged with JG-98. We then used DnaK Y145W to suggest that this protein may be an anti-bacterial target. Indeed, we found that DnaK inhibitors have minimum inhibitory concentration (MIC) values <0.125 µg mL-1 against several pathogens, including multidrug-resistant Staphylococcus aureus (MRSA) strains. We propose that tryptophan scanning mutagenesis may provide a distinct way to address the important problem of target engagement.

8.
Immunity ; 44(6): 1392-405, 2016 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-27287411

RESUMO

Although numerous polymorphisms have been associated with inflammatory bowel disease (IBD), identifying the function of these genetic factors has proved challenging. Here we identified a role for nine genes in IBD susceptibility loci in antibacterial autophagy and characterized a role for one of these genes, GPR65, in maintaining lysosome function. Mice lacking Gpr65, a proton-sensing G protein-coupled receptor, showed increased susceptibly to bacteria-induced colitis. Epithelial cells and macrophages lacking GPR65 exhibited impaired clearance of intracellular bacteria and accumulation of aberrant lysosomes. Similarly, IBD patient cells and epithelial cells expressing an IBD-associated missense variant, GPR65 I231L, displayed aberrant lysosomal pH resulting in lysosomal dysfunction, impaired bacterial restriction, and altered lipid droplet formation. The GPR65 I231L polymorphism was sufficient to confer decreased GPR65 signaling. Collectively, these data establish a role for GPR65 in IBD susceptibility and identify lysosomal dysfunction as a potentially causative element in IBD pathogenesis with effects on cellular homeostasis and defense.


Assuntos
Colite/imunologia , Células Epiteliais/imunologia , Doenças Inflamatórias Intestinais/genética , Lisossomos/fisiologia , Receptores Acoplados a Proteínas G/metabolismo , Infecções por Salmonella/imunologia , Salmonella enterica/imunologia , Salmonella typhimurium/imunologia , Animais , Predisposição Genética para Doença , Células HeLa , Humanos , Doenças Inflamatórias Intestinais/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fagossomos/fisiologia , Polimorfismo Genético , Receptores Acoplados a Proteínas G/genética , Risco
9.
Proc Natl Acad Sci U S A ; 112(31): E4281-7, 2015 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-26195741

RESUMO

Studies of human genetics and pathophysiology have implicated the regulation of autophagy in inflammation, neurodegeneration, infection, and autoimmunity. These findings have motivated the use of small-molecule probes to study how modulation of autophagy affects disease-associated phenotypes. Here, we describe the discovery of the small-molecule probe BRD5631 that is derived from diversity-oriented synthesis and enhances autophagy through an mTOR-independent pathway. We demonstrate that BRD5631 affects several cellular disease phenotypes previously linked to autophagy, including protein aggregation, cell survival, bacterial replication, and inflammatory cytokine production. BRD5631 can serve as a valuable tool for studying the role of autophagy in the context of cellular homeostasis and disease.


Assuntos
Autofagia/efeitos dos fármacos , Genética Médica , Doença de Niemann-Pick Tipo C/genética , Doença de Niemann-Pick Tipo C/patologia , Bibliotecas de Moléculas Pequenas/farmacologia , Bactérias/efeitos dos fármacos , Proteínas de Transporte/metabolismo , Agregação Celular/efeitos dos fármacos , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Ensaios de Triagem em Larga Escala , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Interleucina-1beta/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Glicoproteínas de Membrana/metabolismo , Modelos Biológicos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Proteína C1 de Niemann-Pick , Doença de Niemann-Pick Tipo C/metabolismo , Peptídeos/metabolismo , Fenótipo , Bibliotecas de Moléculas Pequenas/química
10.
Cell Rep ; 11(12): 1905-18, 2015 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-26095365

RESUMO

The polymorphism ATG16L1 T300A, associated with increased risk of Crohn's disease, impairs pathogen defense mechanisms including selective autophagy, but specific pathway interactions altered by the risk allele remain unknown. Here, we use perturbational profiling of human peripheral blood cells to reveal that CLEC12A is regulated in an ATG16L1-T300A-dependent manner. Antibacterial autophagy is impaired in CLEC12A-deficient cells, and this effect is exacerbated in the presence of the ATG16L1(∗)300A risk allele. Clec12a(-/-) mice are more susceptible to Salmonella infection, supporting a role for CLEC12A in antibacterial defense pathways in vivo. CLEC12A is recruited to sites of bacterial entry, bacteria-autophagosome complexes, and sites of sterile membrane damage. Integrated genomics identified a functional interaction between CLEC12A and an E3-ubiquitin ligase complex that functions in antibacterial autophagy. These data identify CLEC12A as early adaptor molecule for antibacterial autophagy and highlight perturbational profiling as a method to elucidate defense pathways in complex genetic disease.


Assuntos
Proteínas de Transporte/genética , Doença de Crohn/genética , Lectinas Tipo C/genética , Receptores Mitogênicos/genética , Infecções por Salmonella/genética , Alelos , Animais , Autofagia/genética , Proteínas Relacionadas à Autofagia , Doença de Crohn/microbiologia , Doença de Crohn/patologia , Predisposição Genética para Doença , Genômica , Humanos , Lectinas Tipo C/biossíntese , Camundongos , Receptores Mitogênicos/biossíntese , Fatores de Risco , Salmonella/patogenicidade , Infecções por Salmonella/microbiologia
11.
J Am Chem Soc ; 137(16): 5563-8, 2015 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-25860544

RESUMO

Lysosomes perform a critical cellular function as a site of degradation for diverse cargoes including proteins, organelles, and pathogens delivered through distinct pathways, and defects in lysosomal function have been implicated in a number of diseases. Recent studies have elucidated roles for the lysosome in the regulation of protein synthesis, metabolism, membrane integrity, and other processes involved in homeostasis. Complex small-molecule natural products have greatly contributed to the investigation of lysosomal function in cellular physiology. Here we report the discovery of a novel, small-molecule modulator of lysosomal acidification derived from diversity-oriented synthesis through high-content screening.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Lisossomos/efeitos dos fármacos , Lisossomos/enzimologia , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , ATPases Vacuolares Próton-Translocadoras/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Lisossomos/metabolismo , Macrolídeos/farmacologia , ATPases Vacuolares Próton-Translocadoras/antagonistas & inibidores
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