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1.
Cell ; 168(5): 843-855.e13, 2017 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-28215706

RESUMO

The transcription-related DNA damage response was analyzed on a genome-wide scale with great spatial and temporal resolution. Upon UV irradiation, a slowdown of transcript elongation and restriction of gene activity to the promoter-proximal ∼25 kb is observed. This is associated with a shift from expression of long mRNAs to shorter isoforms, incorporating alternative last exons (ALEs) that are more proximal to the transcription start site. Notably, this includes a shift from a protein-coding ASCC3 mRNA to a shorter ALE isoform of which the RNA, rather than an encoded protein, is critical for the eventual recovery of transcription. The non-coding ASCC3 isoform counteracts the function of the protein-coding isoform, indicating crosstalk between them. Thus, the ASCC3 gene expresses both coding and non-coding transcript isoforms with opposite effects on transcription recovery after UV-induced DNA damage.


Assuntos
Processamento Alternativo/efeitos da radiação , DNA Helicases/genética , RNA não Traduzido/genética , Transcrição Gênica , Raios Ultravioleta , Linhagem Celular , Éxons , Humanos , RNA Polimerase II/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Elongação da Transcrição Genética/efeitos da radiação , Iniciação da Transcrição Genética/efeitos da radiação
2.
Biochem J ; 481(18): 1143-1171, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39145956

RESUMO

Rare mutations in CARD14 promote psoriasis by inducing CARD14-BCL10-MALT1 complexes that activate NF-κB and MAP kinases. Here, the downstream signalling mechanism of the highly penetrant CARD14E138A alteration is described. In addition to BCL10 and MALT1, CARD14E138A associated with several proteins important in innate immune signalling. Interactions with M1-specific ubiquitin E3 ligase HOIP, and K63-specific ubiquitin E3 ligase TRAF6 promoted BCL10 ubiquitination and were essential for NF-κB and MAP kinase activation. In contrast, the ubiquitin binding proteins A20 and ABIN1, both genetically associated with psoriasis development, negatively regulated signalling by inducing CARD14E138A turnover. CARD14E138A localized to early endosomes and was associated with the AP2 adaptor complex. AP2 function was required for CARD14E138A activation of mTOR complex 1 (mTORC1), which stimulated keratinocyte metabolism, but not for NF-κB nor MAP kinase activation. Furthermore, rapamycin ameliorated CARD14E138A-induced keratinocyte proliferation and epidermal acanthosis in mice, suggesting that blocking mTORC1 may be therapeutically beneficial in CARD14-dependent psoriasis.


Assuntos
Proteínas Adaptadoras de Sinalização CARD , Proliferação de Células , Endossomos , Queratinócitos , Alvo Mecanístico do Complexo 1 de Rapamicina , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Humanos , Animais , Queratinócitos/metabolismo , Camundongos , Proteínas Adaptadoras de Sinalização CARD/metabolismo , Proteínas Adaptadoras de Sinalização CARD/genética , Endossomos/metabolismo , Transdução de Sinais , Psoríase/metabolismo , Psoríase/patologia , Psoríase/genética , Proteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , NF-kappa B/metabolismo , NF-kappa B/genética , Proteína 10 de Linfoma CCL de Células B/metabolismo , Proteína 10 de Linfoma CCL de Células B/genética , Ubiquitinação , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fator 6 Associado a Receptor de TNF/metabolismo , Fator 6 Associado a Receptor de TNF/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Células HEK293 , Transporte Proteico , Guanilato Ciclase
3.
J Cell Sci ; 135(8)2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35302162

RESUMO

SMAD2, an effector of the NODAL/Activin signalling pathway, regulates developmental processes by sensing distinct chromatin states and interacting with different transcriptional partners. However, the network of factors that controls SMAD2 chromatin binding and shapes its transcriptional programme over time is poorly characterised. Here, we combine ATAC-seq with computational footprinting to identify temporal changes in chromatin accessibility and transcription factor activity upon NODAL/Activin signalling. We show that SMAD2 binding induces chromatin opening genome wide. We discover footprints for FOXI3, FOXO3 and ZIC3 at the SMAD2-bound enhancers of the early response genes, Pmepa1 and Wnt3, respectively, and demonstrate their functionality. Finally, we determine a mechanism by which NODAL/Activin signalling induces delayed gene expression, by uncovering a self-enabling transcriptional cascade whereby activated SMADs, together with ZIC3, induce the expression of Wnt3. The resultant activated WNT pathway then acts together with the NODAL/Activin pathway to regulate expression of delayed target genes in prolonged NODAL/Activin signalling conditions. This article has an associated First Person interview with the first author of the paper.


Assuntos
Ativinas , Fatores de Transcrição , Ativinas/metabolismo , Cromatina/genética , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Proteínas de Membrana/metabolismo , Proteína Nodal/metabolismo , Proteína Smad2 , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo
4.
J Biol Inorg Chem ; 29(6): 573-582, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39198276

RESUMO

A series of biotin-functionalized transition metal complexes was prepared by iClick reaction from the corresponding azido complexes with a novel alkyne-functionalized biotin derivative ([Au(triazolatoR,R')(PPh3)], [Pt(dpb)(triazolatoR,R')], [Pt(triazolatoR,R')(terpy)]PF6, and [Ir(ppy)(triazolatoR,R')(terpy)]PF6 with dpb = 1,3-di(2-pyridyl)benzene, ppy = 2-phenylpyridine, and terpy = 2,2':6',2''-terpyridine and R = C6H5, R' = biotin). The complexes were compared to reference compounds lacking the biotin moiety. The binding affinity toward avidin and streptavidin was evaluated with the HABA assay as well as isothermal titration calorimetry (ITC). All compounds exhibit the same binding stoichiometry of complex-to-avidin of 4:1, but the ITC results show that the octahedral Ir(III) compound exhibits a higher binding affinity than the square-planar Pt(II) complex. The antibacterial activity of the compounds was evaluated on a series of Gram-negative and Gram-positive bacterial strains. In particular, the neutral Au(I) and Pt(II) complexes showed significant antibacterial activity against Staphylococcus aureus and Enterococcus faecium at very low micromolar concentrations. The cytotoxicity against a range of eukaryotic cell lines was studied and revealed that the octahedral Ir(III) complex was non-toxic, while the square-planar Pt(II) and linear Au(I) complexes displayed non-selective micromolar activity.


Assuntos
Antibacterianos , Biotina , Ouro , Irídio , Testes de Sensibilidade Microbiana , Platina , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Biotina/química , Ouro/química , Ouro/farmacologia , Irídio/química , Irídio/farmacologia , Platina/química , Platina/farmacologia , Humanos , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/síntese química , Staphylococcus aureus/efeitos dos fármacos , Estrutura Molecular , Relação Estrutura-Atividade
5.
JAMA ; 331(3): 242-244, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38227029

RESUMO

Importance: Interest in artificial intelligence (AI) has reached an all-time high, and health care leaders across the ecosystem are faced with questions about where, when, and how to deploy AI and how to understand its risks, problems, and possibilities. Observations: While AI as a concept has existed since the 1950s, all AI is not the same. Capabilities and risks of various kinds of AI differ markedly, and on examination 3 epochs of AI emerge. AI 1.0 includes symbolic AI, which attempts to encode human knowledge into computational rules, as well as probabilistic models. The era of AI 2.0 began with deep learning, in which models learn from examples labeled with ground truth. This era brought about many advances both in people's daily lives and in health care. Deep learning models are task-specific, meaning they do one thing at a time, and they primarily focus on classification and prediction. AI 3.0 is the era of foundation models and generative AI. Models in AI 3.0 have fundamentally new (and potentially transformative) capabilities, as well as new kinds of risks, such as hallucinations. These models can do many different kinds of tasks without being retrained on a new dataset. For example, a simple text instruction will change the model's behavior. Prompts such as "Write this note for a specialist consultant" and "Write this note for the patient's mother" will produce markedly different content. Conclusions and Relevance: Foundation models and generative AI represent a major revolution in AI's capabilities, ffering tremendous potential to improve care. Health care leaders are making decisions about AI today. While any heuristic omits details and loses nuance, the framework of AI 1.0, 2.0, and 3.0 may be helpful to decision-makers because each epoch has fundamentally different capabilities and risks.


Assuntos
Inteligência Artificial , Atenção à Saúde , Humanos , Inteligência Artificial/classificação , Inteligência Artificial/história , Tomada de Decisões , Atenção à Saúde/história , História do Século XX , História do Século XXI
6.
Neurobiol Dis ; 176: 105963, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36521781

RESUMO

Excessive daytime sleepiness is a recognized non-motor symptom that adversely impacts the quality of life of people with Parkinson's disease (PD), yet effective treatment options remain limited. Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an effective treatment for PD motor signs. Reliable daytime sleep-wake classification using local field potentials (LFPs) recorded from DBS leads implanted in STN can inform the development of closed-loop DBS approaches for prompt detection and disruption of sleep-related neural oscillations. We performed STN DBS lead recordings in three nonhuman primates rendered parkinsonian by administrating neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Reference sleep-wake states were determined on a second-by-second basis by video monitoring of eyes (eyes-open, wake and eyes-closed, sleep). The spectral power in delta (1-4 Hz), theta (4-8 Hz), low-beta (8-20 Hz), high-beta (20-35 Hz), gamma (35-90 Hz), and high-frequency (200-400 Hz) bands were extracted from each wake and sleep epochs for training (70% data) and testing (30% data) a support vector machines classifier for each subject independently. The spectral features yielded reasonable daytime sleep-wake classification (sensitivity: 90.68 ± 1.28; specificity: 88.16 ± 1.08; accuracy: 89.42 ± 0.68; positive predictive value; 88.70 ± 0.89, n = 3). Our findings support the plausibility of monitoring daytime sleep-wake states using DBS lead recordings. These results could have future clinical implications in informing the development of closed-loop DBS approaches for automatic detection and disruption of sleep-related neural oscillations in people with PD to promote wakefulness.


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson , Núcleo Subtalâmico , Animais , Estimulação Encefálica Profunda/métodos , Qualidade de Vida , Núcleo Subtalâmico/fisiologia , Sono/fisiologia , Doença de Parkinson/terapia
7.
Development ; 147(21)2020 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-32994166

RESUMO

The Hippo-YAP/TAZ pathway is an important regulator of tissue growth, but can also control cell fate or tissue morphogenesis. Here, we investigate the function of the Hippo pathway during the development of cartilage, which forms the majority of the skeleton. Previously, YAP was proposed to inhibit skeletal size by repressing chondrocyte proliferation and differentiation. We find that, in vitro, Yap/Taz double knockout impairs murine chondrocyte proliferation, whereas constitutively nuclear nls-YAP5SA accelerates proliferation, in line with the canonical role of this pathway in most tissues. However, in vivo, cartilage-specific knockout of Yap/Taz does not prevent chondrocyte proliferation, differentiation or skeletal growth, but rather results in various skeletal deformities including cleft palate. Cartilage-specific expression of nls-YAP5SA or knockout of Lats1/2 do not increase cartilage growth, but instead lead to catastrophic malformations resembling chondrodysplasia or achondrogenesis. Physiological YAP target genes in cartilage include Ctgf, Cyr61 and several matrix remodelling enzymes. Thus, YAP/TAZ activity controls chondrocyte proliferation in vitro, possibly reflecting a regenerative response, but is dispensable for chondrocyte proliferation in vivo, and instead functions to control cartilage morphogenesis via regulation of the extracellular matrix.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Osso e Ossos/embriologia , Osso e Ossos/metabolismo , Proteínas de Ciclo Celular/metabolismo , Morfogênese , Proteínas Serina-Treonina Quinases/metabolismo , Transativadores/metabolismo , Animais , Osso e Ossos/anormalidades , Osso e Ossos/patologia , Cartilagem/patologia , Núcleo Celular/metabolismo , Proliferação de Células , Condrócitos/metabolismo , Condrócitos/patologia , Fissura Palatina/patologia , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Lâmina de Crescimento/patologia , Via de Sinalização Hippo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Morfogênese/genética , Transdução de Sinais , Proteínas Supressoras de Tumor/metabolismo , Proteínas de Sinalização YAP
8.
J Drugs Dermatol ; 22(5): 440-444, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37133468

RESUMO

IMPORTANCE: Actinic keratosis (AK) is a premalignant lesion that has a1% to 10% potential of progression to squamous cell carcinoma (SCC), but it is not possible to determine which lesions are at higher risk. OBJECTIVE: This study examined the epidermal genetic profiles of actinic keratosis and SCC through non-invasive techniques seeking to develop a biopsy-free method for AK monitoring and aid in the early diagnosis of developing SCC. DESIGN: Ribonucleic acid (RNA) was collected from adhesive tape strips and gene expression levels were measured. A threshold fold change >2 and adjusted P-value <0.05 were used to determine differentially expressed genes. SETTING: Single center dermatology clinic. PARTICIPANTS: Patients who presented to the clinic with lesions suspicious of non-melanoma skin cancer that had never been previously biopsied. MAIN OUTCOME AND MEASURE: RNA was extracted via non-invasive biopsy and sequenced. Low quality samples were filtered out and the remaining samples underwent differential gene expression analysis by DESeq2 in R package. A threshold of fold change >2 and adjusted P-value <0.05 was used for determination of differentially expressed genes. The differentially expressed genes that overlapped between the corrected and uncorrected groups were the most significant for analysis. RESULTS: From 47 lesions, 6 significant differentially expressed genes were found between AK and SCC, and 25 significant differentially expressed genes between in-situ SCC and invasive SCC. Individual samples showed similarities based on diagnosis, suggesting mutations were specific to the disease and not the individual. CONCLUSIONS AND RELEVANCE: These findings highlight which genes may play a role in AK progression to SCC. The genomic differences between in-situ and invasive squamous cell carcinoma open an opportunity for early diagnosis of squamous cell carcinoma and risk prediction of actinic keratosis. J Drugs Dermatol. 2023;22(5): doi:10.36849/JDD.7097.


Assuntos
Carcinoma de Células Escamosas , Ceratose Actínica , Neoplasias Cutâneas , Humanos , Ceratose Actínica/diagnóstico , Ceratose Actínica/genética , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/genética , Epiderme/patologia , RNA
9.
Br J Haematol ; 198(4): 729-739, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35689489

RESUMO

A broad proteomic analysis was conducted to identify and evaluate candidate biomarkers potentially predictive of response to treatment with an oral selective Janus kinase 1 (JAK1) inhibitor, itacitinib, in acute graft-versus-host disease (GVHD). Plasma samples from 25 participants (identification cohort; NCT02614612) were used to identify novel biomarkers that were tested in a validation cohort from a placebo-controlled, randomised trial (n = 210; NCT03139604). The identification cohort received corticosteroids plus 200 or 300 mg itacitinib once daily. The validation cohort received corticosteroids plus 200 mg itacitinib once daily or placebo. A broad proteomic analysis was conducted using a proximity extension assay. Baseline and longitudinal comparisons were performed with unpaired t-test and one-way analysis of variance used to evaluate biomarker level changes. Seven candidate biomarkers were identified. Monocyte-chemotactic protein (MCP)3, pro-calcitonin/calcitonin (ProCALCA/CALCA), together with a previously identified prognostic acute GVHD biomarker, regenerating islet-derived protein (REG)3A, stratified complete responders from non-responders (participants with progressive disease) to itacitinib, but not placebo, potentially representing predictive biomarkers of itacitinib in acute GVHD. ProCALCA/CALCA, suppressor of tumorigenicity (ST)2, and tumour necrosis factor receptor (TNFR)1 were significantly reduced over time by itacitinib in responders, potentially representing response-to-treatment biomarkers. Novel biomarkers have the potential to identify patients with acute GVHD that may respond to itacitinib plus corticosteroid treatment (NCT02614612; NCT03139604).


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Acetonitrilas , Doença Aguda , Corticosteroides/uso terapêutico , Biomarcadores , Doença Enxerto-Hospedeiro/tratamento farmacológico , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Proteômica , Pirazóis , Pirimidinas , Pirróis
10.
Blood ; 135(20): 1739-1749, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-32160294

RESUMO

Patients who develop steroid-refractory acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic cell transplantation have poor prognosis, highlighting an unmet therapeutic need. In this open-label phase 2 study (ClinicalTrials.gov identifier: NCT02953678), patients aged at least 12 years with grades II to IV steroid-refractory aGVHD were eligible to receive ruxolitinib orally, starting at 5 mg twice daily plus corticosteroids, until treatment failure, unacceptable toxicity, or death. The primary end point was overall response rate (ORR) at day 28; the key secondary end point was duration of response (DOR) at 6 months. As of 2 July 2018, 71 patients received at least 1 dose of ruxolitinib. Forty-eight of those patients (67.6%) had grade III/IV aGVHD at enrollment. At day 28, 39 patients (54.9%; 95% confidence interval, 42.7%-66.8%) had an overall response, including 19 (26.8%) with complete responses. Best ORR at any time was 73.2% (complete response, 56.3%). Responses were observed across skin (61.1%), upper (45.5%) and lower (46.0%) gastrointestinal tract, and liver (26.7%). Median DOR was 345 days. Overall survival estimate at 6 months was 51.0%. At day 28, 24 (55.8%) of 43 patients receiving ruxolitinib and corticosteroids had a 50% or greater corticosteroid dose reduction from baseline. The most common treatment-emergent adverse events were anemia (64.8%), thrombocytopenia (62.0%), hypokalemia (49.3%), neutropenia (47.9%), and peripheral edema (45.1%). Ruxolitinib produced durable responses and encouraging survival compared with historical data in patients with steroid-refractory aGVHD who otherwise have dismal outcomes. The safety profile was consistent with expectations for ruxolitinib and this patient population.


Assuntos
Doença Enxerto-Hospedeiro/tratamento farmacológico , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Pirazóis/uso terapêutico , Adolescente , Corticosteroides/uso terapêutico , Adulto , Idoso , Resistência a Medicamentos/efeitos dos fármacos , Feminino , Doença Enxerto-Hospedeiro/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Nitrilas , Pirimidinas , Indução de Remissão , Resultado do Tratamento , Adulto Jovem
11.
Br J Dermatol ; 186(5): 803-813, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34978076

RESUMO

BACKGROUND: Janus kinase (JAK)-mediated cytokine signalling contributes to local and systemic inflammation in hidradenitis suppurativa (HS). OBJECTIVES: To describe the safety and efficacy results from two multicentre phase II trials of the JAK1 inhibitor INCB054707 in patients with moderate-to-severe HS. METHODS: Patients received open-label INCB054707 15 mg once daily (QD; Study 1) or were randomized to INCB054707 30, 60 or 90 mg QD or placebo (3 : 1 within each cohort; Study 2) for 8 weeks. Eligible patients were aged 18-75 years and had moderate-to-severe HS (Hurley stage II/III disease), lesions present in at least two anatomical locations, and a total abscess and inflammatory nodule count ≥ 3. The primary endpoint for both studies was safety and tolerability. Secondary endpoints included HS Clinical Response (HiSCR) and other efficacy measures. RESULTS: Ten patients were enrolled in Study 1 (15 mg INCB054707) and 35 in Study 2 (INCB054707: 30 mg, n = 9; 60 mg, n = 9; 90 mg, n = 8; placebo, n = 9). Overall, 70% of patients in Study 1 and 81% of patients receiving INCB054707 in Study 2 experienced at least one treatment-emergent adverse event; 30% and 42% of patients, respectively, had at least one treatment-related adverse event. Among the evaluable patients, three (43%) in Study 1 and 17 (65% overall: 30 mg, 56%; 60 mg, 56%; 90 mg, 88%) receiving INCB054707 vs. 4 patients (57%) receiving placebo in Study 2 achieved HiSCR at week 8. CONCLUSIONS: INCB054707 was well tolerated, with responses observed in patients with moderate-to-severe HS. The safety and efficacy findings from these studies demonstrate proof of concept for JAK1 inhibition in HS. The studies are registered on ClinicalTrials.gov (NCT03569371 and NCT03607487).


Assuntos
Hidradenite Supurativa , Inibidores de Janus Quinases , Adolescente , Adulto , Idoso , Ensaios Clínicos Fase II como Assunto , Método Duplo-Cego , Hidradenite Supurativa/tratamento farmacológico , Humanos , Janus Quinase 1 , Inibidores de Janus Quinases/efeitos adversos , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
12.
Biochem J ; 478(13): 2425-2443, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34198323

RESUMO

The coronavirus disease 2019 (COVID-19) global pandemic has turned into the largest public health and economic crisis in recent history impacting virtually all sectors of society. There is a need for effective therapeutics to battle the ongoing pandemic. Repurposing existing drugs with known pharmacological safety profiles is a fast and cost-effective approach to identify novel treatments. The COVID-19 etiologic agent is the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a single-stranded positive-sense RNA virus. Coronaviruses rely on the enzymatic activity of the replication-transcription complex (RTC) to multiply inside host cells. The RTC core catalytic component is the RNA-dependent RNA polymerase (RdRp) holoenzyme. The RdRp is one of the key druggable targets for CoVs due to its essential role in viral replication, high degree of sequence and structural conservation and the lack of homologues in human cells. Here, we have expressed, purified and biochemically characterised active SARS-CoV-2 RdRp complexes. We developed a novel fluorescence resonance energy transfer-based strand displacement assay for monitoring SARS-CoV-2 RdRp activity suitable for a high-throughput format. As part of a larger research project to identify inhibitors for all the enzymatic activities encoded by SARS-CoV-2, we used this assay to screen a custom chemical library of over 5000 approved and investigational compounds for novel SARS-CoV-2 RdRp inhibitors. We identified three novel compounds (GSK-650394, C646 and BH3I-1) and confirmed suramin and suramin-like compounds as in vitro SARS-CoV-2 RdRp activity inhibitors. We also characterised the antiviral efficacy of these drugs in cell-based assays that we developed to monitor SARS-CoV-2 growth.


Assuntos
Antivirais/química , Antivirais/farmacologia , RNA-Polimerase RNA-Dependente de Coronavírus/antagonistas & inibidores , Avaliação Pré-Clínica de Medicamentos , SARS-CoV-2/enzimologia , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Benzoatos/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Chlorocebus aethiops , RNA-Polimerase RNA-Dependente de Coronavírus/metabolismo , Ensaios Enzimáticos , Transferência Ressonante de Energia de Fluorescência , Ensaios de Triagem em Larga Escala , Holoenzimas/metabolismo , Reprodutibilidade dos Testes , SARS-CoV-2/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química , Suramina/farmacologia , Células Vero , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/metabolismo
13.
Biochem J ; 478(13): 2405-2423, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34198322

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic, which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a global public health challenge. While the efficacy of vaccines against emerging and future virus variants remains unclear, there is a need for therapeutics. Repurposing existing drugs represents a promising and potentially rapid opportunity to find novel antivirals against SARS-CoV-2. The virus encodes at least nine enzymatic activities that are potential drug targets. Here, we have expressed, purified and developed enzymatic assays for SARS-CoV-2 nsp13 helicase, a viral replication protein that is essential for the coronavirus life cycle. We screened a custom chemical library of over 5000 previously characterized pharmaceuticals for nsp13 inhibitors using a fluorescence resonance energy transfer-based high-throughput screening approach. From this, we have identified FPA-124 and several suramin-related compounds as novel inhibitors of nsp13 helicase activity in vitro. We describe the efficacy of these drugs using assays we developed to monitor SARS-CoV-2 growth in Vero E6 cells.


Assuntos
Antivirais/química , Antivirais/farmacologia , Avaliação Pré-Clínica de Medicamentos , RNA Helicases/antagonistas & inibidores , SARS-CoV-2/enzimologia , Bibliotecas de Moléculas Pequenas/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Chlorocebus aethiops , Ensaios Enzimáticos , Transferência Ressonante de Energia de Fluorescência , Ensaios de Triagem em Larga Escala , RNA Helicases/metabolismo , Reprodutibilidade dos Testes , SARS-CoV-2/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química , Suramina/farmacologia , Células Vero , Proteínas não Estruturais Virais/metabolismo
14.
Biochem J ; 478(13): 2465-2479, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34198324

RESUMO

SARS-CoV-2 is responsible for COVID-19, a human disease that has caused over 2 million deaths, stretched health systems to near-breaking point and endangered economies of countries and families around the world. Antiviral treatments to combat COVID-19 are currently lacking. Remdesivir, the only antiviral drug approved for the treatment of COVID-19, can affect disease severity, but better treatments are needed. SARS-CoV-2 encodes 16 non-structural proteins (nsp) that possess different enzymatic activities with important roles in viral genome replication, transcription and host immune evasion. One key aspect of host immune evasion is performed by the uridine-directed endoribonuclease activity of nsp15. Here we describe the expression and purification of nsp15 recombinant protein. We have developed biochemical assays to follow its activity, and we have found evidence for allosteric behaviour. We screened a custom chemical library of over 5000 compounds to identify nsp15 endoribonuclease inhibitors, and we identified and validated NSC95397 as an inhibitor of nsp15 endoribonuclease in vitro. Although NSC95397 did not inhibit SARS-CoV-2 growth in VERO E6 cells, further studies will be required to determine the effect of nsp15 inhibition on host immune evasion.


Assuntos
Antivirais/química , Antivirais/farmacologia , Avaliação Pré-Clínica de Medicamentos , Endorribonucleases/antagonistas & inibidores , SARS-CoV-2/enzimologia , Bibliotecas de Moléculas Pequenas/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Regulação Alostérica , Animais , Chlorocebus aethiops , Endorribonucleases/isolamento & purificação , Endorribonucleases/metabolismo , Ensaios Enzimáticos , Fluorescência , Ensaios de Triagem em Larga Escala , Técnicas In Vitro , Cinética , Naftoquinonas/farmacologia , Reprodutibilidade dos Testes , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/crescimento & desenvolvimento , Bibliotecas de Moléculas Pequenas/química , Soluções , Células Vero , Proteínas não Estruturais Virais/isolamento & purificação , Proteínas não Estruturais Virais/metabolismo
15.
Biochem J ; 478(13): 2517-2531, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34198325

RESUMO

The COVID-19 pandemic has emerged as the biggest life-threatening disease of this century. Whilst vaccination should provide a long-term solution, this is pitted against the constant threat of mutations in the virus rendering the current vaccines less effective. Consequently, small molecule antiviral agents would be extremely useful to complement the vaccination program. The causative agent of COVID-19 is a novel coronavirus, SARS-CoV-2, which encodes at least nine enzymatic activities that all have drug targeting potential. The papain-like protease (PLpro) contained in the nsp3 protein generates viral non-structural proteins from a polyprotein precursor, and cleaves ubiquitin and ISG protein conjugates. Here we describe the expression and purification of PLpro. We developed a protease assay that was used to screen a custom compound library from which we identified dihydrotanshinone I and Ro 08-2750 as compounds that inhibit PLpro in protease and isopeptidase assays and also inhibit viral replication in cell culture-based assays.


Assuntos
Antivirais/química , Antivirais/farmacologia , Proteases Semelhantes à Papaína de Coronavírus/antagonistas & inibidores , Avaliação Pré-Clínica de Medicamentos , SARS-CoV-2/enzimologia , Bibliotecas de Moléculas Pequenas/farmacologia , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacologia , Alanina/análogos & derivados , Alanina/farmacologia , Compostos de Anilina/farmacologia , Animais , Benzamidas/farmacologia , Chlorocebus aethiops , Proteases Semelhantes à Papaína de Coronavírus/genética , Proteases Semelhantes à Papaína de Coronavírus/isolamento & purificação , Proteases Semelhantes à Papaína de Coronavírus/metabolismo , Sinergismo Farmacológico , Ensaios Enzimáticos , Flavinas/farmacologia , Transferência Ressonante de Energia de Fluorescência , Furanos/farmacologia , Ensaios de Triagem em Larga Escala , Concentração Inibidora 50 , Naftalenos/farmacologia , Fenantrenos/farmacologia , Quinonas/farmacologia , Reprodutibilidade dos Testes , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/crescimento & desenvolvimento , Bibliotecas de Moléculas Pequenas/química , Células Vero , Replicação Viral/efeitos dos fármacos
16.
Biochem J ; 478(13): 2445-2464, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34198326

RESUMO

SARS-CoV-2 is a coronavirus that emerged in 2019 and rapidly spread across the world causing a deadly pandemic with tremendous social and economic costs. Healthcare systems worldwide are under great pressure, and there is an urgent need for effective antiviral treatments. The only currently approved antiviral treatment for COVID-19 is remdesivir, an inhibitor of viral genome replication. SARS-CoV-2 proliferation relies on the enzymatic activities of the non-structural proteins (nsp), which makes them interesting targets for the development of new antiviral treatments. With the aim to identify novel SARS-CoV-2 antivirals, we have purified the exoribonuclease/methyltransferase (nsp14) and its cofactor (nsp10) and developed biochemical assays compatible with high-throughput approaches to screen for exoribonuclease inhibitors. We have screened a library of over 5000 commercial compounds and identified patulin and aurintricarboxylic acid (ATA) as inhibitors of nsp14 exoribonuclease in vitro. We found that patulin and ATA inhibit replication of SARS-CoV-2 in a VERO E6 cell-culture model. These two new antiviral compounds will be valuable tools for further coronavirus research as well as potentially contributing to new therapeutic opportunities for COVID-19.


Assuntos
Antivirais/química , Antivirais/farmacologia , Avaliação Pré-Clínica de Medicamentos , Exorribonucleases/antagonistas & inibidores , SARS-CoV-2/enzimologia , Bibliotecas de Moléculas Pequenas/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas Virais Reguladoras e Acessórias/antagonistas & inibidores , Animais , Ácido Aurintricarboxílico/farmacologia , Chlorocebus aethiops , Ensaios Enzimáticos , Exorribonucleases/metabolismo , Fluorescência , Ensaios de Triagem em Larga Escala , Patulina/farmacologia , Reprodutibilidade dos Testes , SARS-CoV-2/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química , Células Vero , Proteínas não Estruturais Virais/metabolismo , Proteínas Virais Reguladoras e Acessórias/metabolismo
17.
Biochem J ; 478(13): 2481-2497, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34198328

RESUMO

The COVID-19 pandemic has presented itself as one of the most critical public health challenges of the century, with SARS-CoV-2 being the third member of the Coronaviridae family to cause a fatal disease in humans. There is currently only one antiviral compound, remdesivir, that can be used for the treatment of COVID-19. To identify additional potential therapeutics, we investigated the enzymatic proteins encoded in the SARS-CoV-2 genome. In this study, we focussed on the viral RNA cap methyltransferases, which play key roles in enabling viral protein translation and facilitating viral escape from the immune system. We expressed and purified both the guanine-N7 methyltransferase nsp14, and the nsp16 2'-O-methyltransferase with its activating cofactor, nsp10. We performed an in vitro high-throughput screen for inhibitors of nsp14 using a custom compound library of over 5000 pharmaceutical compounds that have previously been characterised in either clinical or basic research. We identified four compounds as potential inhibitors of nsp14, all of which also showed antiviral capacity in a cell-based model of SARS-CoV-2 infection. Three of the four compounds also exhibited synergistic effects on viral replication with remdesivir.


Assuntos
Antivirais/farmacologia , Avaliação Pré-Clínica de Medicamentos , Exorribonucleases/antagonistas & inibidores , Metiltransferases/antagonistas & inibidores , Capuzes de RNA/metabolismo , SARS-CoV-2/enzimologia , Bibliotecas de Moléculas Pequenas/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacologia , Alanina/análogos & derivados , Alanina/farmacologia , Animais , Antivirais/química , Clorobenzenos/farmacologia , Chlorocebus aethiops , Ensaios Enzimáticos , Exorribonucleases/genética , Exorribonucleases/isolamento & purificação , Exorribonucleases/metabolismo , Transferência Ressonante de Energia de Fluorescência , Ensaios de Triagem em Larga Escala , Indazóis/farmacologia , Indenos/farmacologia , Indóis/farmacologia , Metiltransferases/genética , Metiltransferases/isolamento & purificação , Metiltransferases/metabolismo , Nitrilas/farmacologia , Fenotiazinas/farmacologia , Purinas/farmacologia , Reprodutibilidade dos Testes , SARS-CoV-2/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química , Especificidade por Substrato , Trifluperidol/farmacologia , Células Vero , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/isolamento & purificação , Proteínas não Estruturais Virais/metabolismo , Proteínas Virais Reguladoras e Acessórias/genética , Proteínas Virais Reguladoras e Acessórias/isolamento & purificação , Proteínas Virais Reguladoras e Acessórias/metabolismo
18.
Biochem J ; 478(13): 2499-2515, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34198327

RESUMO

The coronavirus 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), spread around the world with unprecedented health and socio-economic effects for the global population. While different vaccines are now being made available, very few antiviral drugs have been approved. The main viral protease (nsp5) of SARS-CoV-2 provides an excellent target for antivirals, due to its essential and conserved function in the viral replication cycle. We have expressed, purified and developed assays for nsp5 protease activity. We screened the nsp5 protease against a custom chemical library of over 5000 characterised pharmaceuticals. We identified calpain inhibitor I and three different peptidyl fluoromethylketones (FMK) as inhibitors of nsp5 activity in vitro, with IC50 values in the low micromolar range. By altering the sequence of our peptidomimetic FMK inhibitors to better mimic the substrate sequence of nsp5, we generated an inhibitor with a subnanomolar IC50. Calpain inhibitor I inhibited viral infection in monkey-derived Vero E6 cells, with an EC50 in the low micromolar range. The most potent and commercially available peptidyl-FMK compound inhibited viral growth in Vero E6 cells to some extent, while our custom peptidyl FMK inhibitor offered a marked antiviral improvement.


Assuntos
Antivirais/química , Antivirais/farmacologia , Proteases 3C de Coronavírus/antagonistas & inibidores , Avaliação Pré-Clínica de Medicamentos , SARS-CoV-2/enzimologia , Bibliotecas de Moléculas Pequenas/farmacologia , Clorometilcetonas de Aminoácidos/farmacologia , Animais , Azóis/farmacologia , Chlorocebus aethiops , Proteases 3C de Coronavírus/genética , Proteases 3C de Coronavírus/isolamento & purificação , Proteases 3C de Coronavírus/metabolismo , Ensaios Enzimáticos , Transferência Ressonante de Energia de Fluorescência , Ensaios de Triagem em Larga Escala , Isoindóis , Leupeptinas/farmacologia , Compostos Organosselênicos/farmacologia , Peptidomiméticos , Proteínas de Ligação a RNA/metabolismo , Reprodutibilidade dos Testes , SARS-CoV-2/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química , Células Vero , Proteínas não Estruturais Virais/metabolismo
19.
J Drugs Dermatol ; 21(2): 141-145, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35133118

RESUMO

BACKGROUND: Malassezin is a natural indole compound produced by the fungus Malassezia furfur and preclinical investigations have demonstrated an ability to suppress melanogenesis. OBJECTIVE: To investigate the histopathological effects of malassezin for treatment of facial hyperpigmentation. METHODS: In this proof-of-concept study, seven subjects with facial hyperpigmentation caused by melasma or photodamage applied topical malassezin twice daily for 14 weeks, followed by eight weeks of observation. At baseline, 2 mm punch biopsies were taken from hyperpigmented areas and adjacent uninvolved skin. Skin biopsies from hyperpigmented areas were repeated at 8, 14, and 22 weeks. Paraffin-embedded sections were cut and stained with H&E, Fontana Masson, and MART 1 and assessed for histopathological changes. RESULTS: Increased epidermal melanin and dermal melanophages were observed in all biopsies at baseline in the hyperpigmented compared to uninvolved skin of all subjects. Eight and 14 week biopsies of involved skin revealed decreased epidermal melanin in all subjects treated with malassezin. Melanocytes appeared less dendritic compared to baseline, and numbers were slightly reduced at eight weeks. Biopsies at 22 weeks showed no significant difference in epidermal melanin levels compared to baseline hyperpigmented skin, and melanocytes were comparable in number and dendricity to baseline. There was no evidence of melanocyte atypia in any of the biopsies. These features were similar in melasma and photo-damaged skin. CONCLUSION: This study documents the histopathological features and ability of malassezin, a novel agent unique to the skin microbiome, to decrease epidermal pigmentation and the temporary and revisable nature of the process. J Drugs Dermatol. 2022;21(2):141-145. doi:10.36849/JDD.6596.


Assuntos
Hiperpigmentação , Microbiota , Humanos , Hiperpigmentação/tratamento farmacológico , Indóis , Melanócitos
20.
Lancet ; 396(10244): 110-120, 2020 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-32653055

RESUMO

BACKGROUND: Vitiligo is a chronic autoimmune disease resulting in skin depigmentation and reduced quality of life. There is no approved treatment for vitiligo repigmentation and current off-label therapies have limited efficacy, emphasising the need for improved treatment options. We investigated the therapeutic potential of ruxolitinib cream in patients with vitiligo and report the efficacy and safety results up to 52 weeks of double-blind treatment. METHODS: We did a multicentre, randomised, double-blind, phase 2 study for adult patients with vitiligo in 26 US hospitals and medical centres in 18 states. Patients with depigmentation of 0·5% or more of their facial body surface area (BSA) and 3% or more of their non-facial BSA were randomly assigned (1:1:1:1:1) by use of an interactive response technology system to receive ruxolitinib cream (1·5% twice daily, 1·5% once daily, 0·5% once daily, or 0·15% once daily) or vehicle (control group) twice daily on lesions constituting 20% or less of their total BSA for 24 weeks. Patients in the control group in addition to patients in the 0·15% once daily group who did not show a 25% or higher improvement from baseline in facial Vitiligo Area Scoring Index (F-VASI) at week 24 were re-randomised to one of three higher ruxolitinib cream doses (0·5% once daily, 1·5% once daily, 1·5% twice daily). Patients in the 0·5% once daily, 1·5% once daily, or 1·5% twice daily groups remained at their original dose up to week 52. Patients, investigators, and the study sponsor (except members of the interim analysis and primary endpoint analysis data monitoring teams) remained masked to treatment assignment throughout the study. The primary endpoint was the proportion of patients achieving a 50% or higher improvement from baseline in F-VASI (F-VASI50) at week 24, assessed in the intention-to-treat population. The study is registered with ClinicalTrials.gov, NCT03099304. FINDINGS: Between June 7, 2017, and March 21, 2018, 205 patients were screened for eligibility, 48 were excluded and 157 patients (mean age, 48·3 years [SD 12·9]; 73 [46%] male and 84 [54%] female) were randomly assigned to either an intervention group or the control group. 32 (20%) of 157 were assigned to the control group, 31 (20%) to the 0·15% once daily group, 31 (20%) to the 0·5% once daily group, 30 (19%) to the 1·5% once daily group, and 33 (21%) to the 1·5% twice daily group. F-VASI50 at week 24 was reached by significantly more patients given ruxolitinib cream at 1·5% twice daily (15 [45%] of 33) and 1·5% once daily (15 [50%] of 30) than were treated with vehicle (one [3%] of 32). Four patients had serious treatment-emergent adverse events (one patient in the 1·5% twice daily group developed subdural haematoma; one patient in the 1·5% once daily group had a seizure; one patient in the 0·5% once daily group had coronary artery occlusion; and one patient in the 0·5% once daily group had oesophageal achalasia), all of which were unrelated to study treatment. Application site pruritus was the most common treatment-related adverse event among patients given ruxolitinib cream (one [3%] of 33 in the 1·5% twice daily group; three [10%] of 30 in the 1·5% once daily group; three [10%] of 31 in the 0·5% once daily group; and six [19%] of 31 in the 0·15% once daily group)with three [9%] of 32 patients showing application site pruritis in the control group. Acne was noted as a treatment-related adverse event in 13 (10%) of 125 patients who received ruxolitinib cream and one (3%) of 32 patients who received vehicle cream. All treatment-related adverse events were mild or moderate in severity and similar across treatment groups. INTERPRETATION: Treatment with ruxolitinib cream was associated with substantial repigmentation of vitiligo lesions up to 52 weeks of treatment, and all doses were well tolerated. These data suggest that ruxolitinib cream might be an effective treatment option for patients with vitiligo. FUNDING: Incyte.


Assuntos
Inibidores de Janus Quinases/uso terapêutico , Pirazóis/uso terapêutico , Vitiligo/tratamento farmacológico , Adulto , Estudos de Casos e Controles , Método Duplo-Cego , Feminino , Humanos , Inibidores de Janus Quinases/administração & dosagem , Inibidores de Janus Quinases/efeitos adversos , Masculino , Pessoa de Meia-Idade , Nitrilas , Pirazóis/administração & dosagem , Pirazóis/efeitos adversos , Pirimidinas , Creme para a Pele/administração & dosagem , Resultado do Tratamento
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