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1.
Front Med (Lausanne) ; 11: 1370916, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38966540

RESUMO

Introduction: The conect4children (c4c) project aims to facilitate efficient planning and delivery of paediatric clinical trials. One objective of c4c is data standardization and reuse. Interoperability and reusability of paediatric clinical trial data is challenging due to a lack of standardization. The Clinical Data Interchange Standards Consortium (CDISC) standards that are required or recommended for regulatory submissions in several countries lack paediatric specificity with limited awareness within academic institutions. To address this, c4c and CDISC collaborated to develop the Pediatrics User Guide (PUG) consisting of cross-cutting data items that are routinely collected in paediatric clinical trials, factoring in all paediatric age ranges. Methods and Results: The development of the PUG consisted of six stages. During the scoping phase, subtopics (each containing several clinically relevant concepts) were suggested and debated for inclusion in the PUG. Ninety concepts were selected for the modelling phase. Concept maps describing the Research Topic and representation procedure were developed for the 19 concepts that had no (or partial) previous modelling in CDISC. Next, metadata and implementation examples were developed for concepts. This was followed by a CDISC internal review and a public review. For both these review stages, the feedback comments were either implemented or rejected based on budget, timelines, expert review, and scope. The PUG was published on the CDISC website on February 23, 2023. Discussion: The PUG is a first step in bridging the lack of child specific CDISC standards, particularly within academia. Several academic and industrial partners were involved in the development of the PUG, and c4c has undertaken multiple steps to publicize the PUG within its academic partner organizations - in particular, the European Reference Networks (ERNs) that are developing registries and dictionaries in 24 disease areas. In the long term, continued use of the PUG in paediatric clinical trials will enable the pooling of data from multiple trials, which is particularly important for medical domains with small populations.

2.
AIDS Res Ther ; 20(1): 35, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37296413

RESUMO

BACKGROUND: Effective antiretroviral therapy (ART) in people living with HIV (PLWH) has improved life expectancy and increased risk of age-associated cardiometabolic comorbidities. At-risk alcohol use is more frequent among PLWH and increases the risk of health challenges. PLWH with at-risk alcohol use are more likely to meet criteria for prediabetes/diabetes and this is associated with impaired whole-body glucose-insulin dynamics. METHODS: The Alcohol & Metabolic Comorbidities in PLWH: Evidence Driven Interventions Study (ALIVE-Ex Study, NCT03299205) is a longitudinal, prospective, interventional study to determine the effects of an aerobic exercise protocol on improving dysglycemia among PLWH with at-risk alcohol use. The intervention is a moderate intensity aerobic exercise protocol implemented 3 days per week for 10 weeks at the Louisiana State University Health Sciences Center-New Orleans. Participants who have a fasting blood glucose level between 94 and 125 mg/dl will be enrolled in the study. Oral glucose tolerance tests, fitness assessments, and skeletal muscle biopsies will be performed pre- and post-exercise intervention. The primary outcome is to determine whether the exercise protocol improves measures of whole-body glucose-insulin dynamics, cardiorespiratory fitness, and skeletal muscle metabolic and bioenergetic function. Secondary outcomes are to determine whether the exercise intervention improves cognitive function and overall quality of life. Results generated will demonstrate the effect of exercise on glycemic measures in PLWH with subclinical dysglycemia and at-risk alcohol use. CONCLUSIONS: The proposed intervention will also have the potential to be scalable to promote lifestyle changes among PLWH, particularly in underserved communities.


Assuntos
Infecções por HIV , Insulinas , Humanos , Infecções por HIV/terapia , Infecções por HIV/tratamento farmacológico , Qualidade de Vida , Estudos Prospectivos , Exercício Físico , Terapia por Exercício , Insulinas/uso terapêutico , Glucose/uso terapêutico
3.
Cancer Chemother Pharmacol ; 91(3): 267-280, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36914828

RESUMO

PURPOSE: Galectin-3, a ß-galactoside-binding lectin, plays a key role in several cellular pathways involved in chronic inflammation, heart disease and cancer. GB1211 is an orally bioavailable galectin-3 inhibitor, developed to be systemically active. We report safety and pharmacokinetics (PK) of GB1211 in healthy participants. METHODS: This phase 1, double-blind, placebo-controlled, first-in-human study (NCT03809052) included a single ascending-dose phase (with a food-effect cohort) where participants across seven sequential cohorts were randomized 3:1 to receive oral GB1211 (5, 20, 50, 100, 200 or 400 mg) or placebo. In the multiple ascending-dose phase, participants received 50 or 100 mg GB1211 or placebo twice daily for 10 days. All doses were administered in the fasted state except in the food-effect cohort where doses were given 30 min after a high-fat meal. RESULTS: All 78 participants received at least one GB1211 dose (n = 58) or placebo (n = 20) and completed the study. No safety concerns were identified. Following single and multiple oral doses under fasted conditions, maximum GB1211 plasma concentrations were reached at 1.75-4 h (median) post-dose; mean half-life was 11-16 h. There was a ~ twofold GB1211 accumulation in plasma with multiple dosing, with steady-state reached within 3 days; 30% of the administered dose was excreted in urine as unchanged drug. Absorption in the fed state was delayed by 2 h but systemic exposure was unaffected. CONCLUSION: GB1211 was well tolerated, rapidly absorbed, and displayed favorable PK, indicating a potential to treat multiple disease types. These findings support further clinical development of GB1211. CLINICAL TRIAL REGISTRATION: The study was registered with ClinicalTrials.gov (identifier: NCT03809052).


Assuntos
Galectina 3 , Humanos , Administração Oral , Área Sob a Curva , Relação Dose-Resposta a Droga , Método Duplo-Cego , Galectina 3/antagonistas & inibidores , Voluntários Saudáveis
5.
Cell Rep ; 38(11): 110535, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35294869

RESUMO

As central effectors of ubiquitin (Ub)-mediated proteolysis, proteasomes are regulated at multiple levels, including degradation of unwanted or dysfunctional particles via autophagy (termed proteaphagy). In yeast, inactive proteasomes are exported from the nucleus, sequestered into cytoplasmic aggresomes via the Hsp42 chaperone, extensively ubiquitylated, and then tethered to the expanding phagophore by the autophagy receptor Cue5. Here, we demonstrate the need for ubiquitylation driven by the trio of Ub ligases (E3s), San1, Rsp5, and Hul5, which together with their corresponding E2s work sequentially to promote nuclear export and Cue5 recognition. Whereas San1 functions prior to nuclear export, Rsp5 and Hul5 likely decorate aggresome-localized proteasomes in concert. Ultimately, topologically complex Ub chain(s) containing both K48 and K63 Ub-Ub linkages are assembled, mainly on the regulatory particle, to generate autophagy-competent substrates. Because San1, Rsp5, Hul5, Hsp42, and Cue5 also participate in general proteostasis, proteaphagy likely engages a fundamental mechanism for eliminating inactive/misfolded proteins.


Assuntos
Proteínas de Saccharomyces cerevisiae , Ubiquitina , Autofagia/fisiologia , Proteínas de Choque Térmico/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
9.
Artigo em Inglês | MEDLINE | ID: mdl-38655429

RESUMO

Introduction: A guiding principle behind the development and deployment of the REDCap data management platform has always included attention to workflow design that allows easy implementation of best practices for clinical and translational researchers. CDISC standards such as CDASH have helped the clinical research community improve the efficiency, actionability, and quality of their clinical trials data, but have had limited uptake among the academic institutions. Objective: To create a scalable methodology to convert CDISC CDASH eCRF instrument metadata into REDCap data dictionaries for the purpose of simplifying adoption and use of CDASH instruments by research teams across the REDCap Consortium. Implementation: We have used our replicable methods to translate metadata from 34 CDASH Foundational eCRFs and 20 CDASH Crohn's Disease eCRFs into REDCap eCRF metadata and have made these instruments available in the REDCap Shared Data Instrument Library for widespread sharing and uptake across the REDCap Consortium. Users can import the standardized eCRFs directly into their REDCap projects for immediate use in clinical trial data collection. Conclusion: Disseminating CDISC standards through the REDCap community will increase the accessibility of these standards for academic medical centers. Having academic clinical researchers using CDISC standards may lead to more research datasets that interoperate with pharmaceutical sponsored trials, and more discoveries from secondary use of clinical research data.

10.
Eur J Pharmacol ; 913: 174618, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34762934

RESUMO

Fibrosis is the formation of scar tissue due to injury or long-term inflammation and is a leading cause of morbidity and mortality. Activation of the pro-fibrotic cytokine transforming growth factor-ß (TGFß) via the alpha-V beta-6 (αvß6) integrin has been identified as playing a key role in the development of fibrosis. Therefore, a drug discovery programme to identify an orally bioavailable small molecule αvß6 arginyl-glycinyl-aspartic acid (RGD)-mimetic was initiated. As part of a medicinal chemistry programme GSK3335103 was identified and profiled in a range of pre-clinical in vitro and in vivo systems. GSK3335103 was shown to bind to the αvß6 with high affinity and demonstrated fast binding kinetics. In primary human lung epithelial cells, GSK3335103-induced concentration- and time-dependent internalisation of αvß6 with a rapid return of integrin to the cell surface observed after washout. Following sustained engagement of the αvß6 integrin in vitro, lysosomal degradation was induced by GSK3335103. GSK3335103 was shown to engage with the αvß6 integrin and inhibit the activation of TGFß in both ex vivo IPF tissue and in a murine model of bleomycin-induced lung fibrosis, as measured by αvß6 engagement, TGFß signalling and collagen deposition, with a prolonged duration of action observed in vivo. In summary, GSK3335103 is a potent αvß6 inhibitor that attenuates TGFß signalling in vitro and in vivo with a well-defined pharmacokinetic/pharmacodynamic relationship. This translates to a significant reduction of collagen deposition in vivo and therefore GSK3335103 represents a potential novel oral therapy for fibrotic disorders.


Assuntos
Antifibróticos/farmacologia , Integrinas/antagonistas & inibidores , Fibrose Pulmonar/tratamento farmacológico , Administração Oral , Animais , Antifibróticos/química , Antifibróticos/uso terapêutico , Antígenos de Neoplasias/química , Antígenos de Neoplasias/metabolismo , Disponibilidade Biológica , Bleomicina/administração & dosagem , Bleomicina/toxicidade , Células Cultivadas , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Humanos , Integrinas/química , Integrinas/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/patologia , Lisossomos/metabolismo , Masculino , Camundongos , Oligopeptídeos/química , Cultura Primária de Células , Proteólise/efeitos dos fármacos , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/patologia , Fator de Crescimento Transformador beta/metabolismo
11.
N Engl J Med ; 385(25): 2348-2360, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34587382

RESUMO

BACKGROUND: The safety and efficacy of the AZD1222 (ChAdOx1 nCoV-19) vaccine in a large, diverse population at increased risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the United States, Chile, and Peru has not been known. METHODS: In this ongoing, double-blind, randomized, placebo-controlled, phase 3 clinical trial, we investigated the safety, vaccine efficacy, and immunogenicity of two doses of AZD1222 as compared with placebo in preventing the onset of symptomatic and severe coronavirus disease 2019 (Covid-19) 15 days or more after the second dose in adults, including older adults, in the United States, Chile, and Peru. RESULTS: A total of 32,451 participants underwent randomization, in a 2:1 ratio, to receive AZD1222 (21,635 participants) or placebo (10,816 participants). AZD1222 was safe, with low incidences of serious and medically attended adverse events and adverse events of special interest; the incidences were similar to those observed in the placebo group. Solicited local and systemic reactions were generally mild or moderate in both groups. Overall estimated vaccine efficacy was 74.0% (95% confidence interval [CI], 65.3 to 80.5; P<0.001) and estimated vaccine efficacy was 83.5% (95% CI, 54.2 to 94.1) in participants 65 years of age or older. High vaccine efficacy was consistent across a range of demographic subgroups. In the fully vaccinated analysis subgroup, no severe or critical symptomatic Covid-19 cases were observed among the 17,662 participants in the AZD1222 group; 8 cases were noted among the 8550 participants in the placebo group (<0.1%). The estimated vaccine efficacy for preventing SARS-CoV-2 infection (nucleocapsid antibody seroconversion) was 64.3% (95% CI, 56.1 to 71.0; P<0.001). SARS-CoV-2 spike protein binding and neutralizing antibodies increased after the first dose and increased further when measured 28 days after the second dose. CONCLUSIONS: AZD1222 was safe and efficacious in preventing symptomatic and severe Covid-19 across diverse populations that included older adults. (Funded by AstraZeneca and others; ClinicalTrials.gov number, NCT04516746.).


Assuntos
COVID-19/prevenção & controle , ChAdOx1 nCoV-19 , Eficácia de Vacinas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , COVID-19/epidemiologia , ChAdOx1 nCoV-19/efeitos adversos , Chile/epidemiologia , Método Duplo-Cego , Feminino , Humanos , Imunogenicidade da Vacina , Masculino , Pessoa de Meia-Idade , Peru/epidemiologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Estados Unidos/epidemiologia , Adulto Jovem
12.
Am J Physiol Regul Integr Comp Physiol ; 321(5): R781-R790, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34585616

RESUMO

At-risk alcohol use is prevalent and increases dysglycemia among people living with human immunodeficiency virus (PLWH). Skeletal muscle (SKM) bioenergetic dysregulation is implicated in dysglycemia and type 2 diabetes. The objective of this study was to determine the relationship between at-risk alcohol, glucose tolerance, and SKM bioenergetic function in PLWH. Thirty-five PLWH (11 females, 24 males, age: 53 ± 9 yr, body mass index: 29.0 ± 6.6 kg/m2) with elevated fasting glucose enrolled in the ALIVE-Ex study provided medical history and alcohol use information [Alcohol Use Disorders Identification Test (AUDIT)], then underwent an oral glucose tolerance test (OGTT) and SKM biopsy. Bioenergetic health and function and mitochondrial volume were measured in isolated myoblasts. Mitochondrial gene expression was measured in SKM. Linear regression adjusting for age, sex, and smoking was performed to examine the relationship between glucose tolerance (2-h glucose post-OGTT), AUDIT, and their interaction with each outcome measure. Negative indicators of bioenergetic health were significantly (P < 0.05) greater with higher 2-h glucose (proton leak) and AUDIT (proton leak, nonmitochondrial oxygen consumption, and bioenergetic health index). Mitochondrial volume was increased with the interaction of higher 2-h glucose and AUDIT. Mitochondrial gene expression decreased with higher 2-h glucose (TFAM, PGC1B, PPARG, MFN1), AUDIT (MFN1, DRP1, MFF), and their interaction (PPARG, PPARD, MFF). Decreased expression of mitochondrial genes were coupled with increased mitochondrial volume and decreased bioenergetic health in SKM of PLWH with higher AUDIT and 2-h glucose. We hypothesize these mechanisms reflect poorer mitochondrial health and may precede overt SKM bioenergetic dysregulation observed in type 2 diabetes.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Metabolismo Energético , Infecções por HIV/metabolismo , Sobreviventes de Longo Prazo ao HIV , Mitocôndrias Musculares/metabolismo , Mioblastos Esqueléticos/metabolismo , Músculo Quadríceps/metabolismo , Adulto , Consumo de Bebidas Alcoólicas/sangue , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/fisiopatologia , Biomarcadores/sangue , Células Cultivadas , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/fisiopatologia , Humanos , Resistência à Insulina , Louisiana/epidemiologia , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio , Músculo Quadríceps/fisiopatologia , Medição de Risco , Fatores de Risco , Adulto Jovem
13.
Ochsner J ; 21(2): 224-229, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34239388

RESUMO

Background: Differentiated thyroid cancer (DTC) is comprised of papillary and follicular subtypes, and both have an overall excellent long-term prognosis. Patients with localized DTC that is successfully treated, usually with surgery, exhibit long-term survival well above 90%. In contrast, patients who develop distant metastatic disease have a significantly worse overall prognosis and outcome, often with disease that is refractory to conventional therapy such as surgery, radioactive iodine, and hormone suppression. For patients who recur with distant metastatic disease, limited effective treatment options are available, and most die of their disease within 5 years of recurrence. Case Report: We report the case of a 26-year-old female who presented with recurrent papillary thyroid cancer and a metastatic lesion isolated to the liver. Because of the extremely large size of the metastatic liver mass upon initial presentation, we took a neoadjuvant, multifaceted approach to treatment that included selective internal radioembolization therapy, an oral multikinase inhibitor, and surgical resection of the tumor mass after maximal reduction in tumor size. However, the patient died of metastatic DTC after 39 months of treatment. Conclusion: A multimodal, comprehensive approach to managing such complex patients is essential to optimize both the sequence and therapeutic approach to treatment.

15.
Lancet ; 397(10277): 881-891, 2021 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-33617777

RESUMO

BACKGROUND: The ChAdOx1 nCoV-19 (AZD1222) vaccine has been approved for emergency use by the UK regulatory authority, Medicines and Healthcare products Regulatory Agency, with a regimen of two standard doses given with an interval of 4-12 weeks. The planned roll-out in the UK will involve vaccinating people in high-risk categories with their first dose immediately, and delivering the second dose 12 weeks later. Here, we provide both a further prespecified pooled analysis of trials of ChAdOx1 nCoV-19 and exploratory analyses of the impact on immunogenicity and efficacy of extending the interval between priming and booster doses. In addition, we show the immunogenicity and protection afforded by the first dose, before a booster dose has been offered. METHODS: We present data from three single-blind randomised controlled trials-one phase 1/2 study in the UK (COV001), one phase 2/3 study in the UK (COV002), and a phase 3 study in Brazil (COV003)-and one double-blind phase 1/2 study in South Africa (COV005). As previously described, individuals 18 years and older were randomly assigned 1:1 to receive two standard doses of ChAdOx1 nCoV-19 (5 × 1010 viral particles) or a control vaccine or saline placebo. In the UK trial, a subset of participants received a lower dose (2·2 × 1010 viral particles) of the ChAdOx1 nCoV-19 for the first dose. The primary outcome was virologically confirmed symptomatic COVID-19 disease, defined as a nucleic acid amplification test (NAAT)-positive swab combined with at least one qualifying symptom (fever ≥37·8°C, cough, shortness of breath, or anosmia or ageusia) more than 14 days after the second dose. Secondary efficacy analyses included cases occuring at least 22 days after the first dose. Antibody responses measured by immunoassay and by pseudovirus neutralisation were exploratory outcomes. All cases of COVID-19 with a NAAT-positive swab were adjudicated for inclusion in the analysis by a masked independent endpoint review committee. The primary analysis included all participants who were SARS-CoV-2 N protein seronegative at baseline, had had at least 14 days of follow-up after the second dose, and had no evidence of previous SARS-CoV-2 infection from NAAT swabs. Safety was assessed in all participants who received at least one dose. The four trials are registered at ISRCTN89951424 (COV003) and ClinicalTrials.gov, NCT04324606 (COV001), NCT04400838 (COV002), and NCT04444674 (COV005). FINDINGS: Between April 23 and Dec 6, 2020, 24 422 participants were recruited and vaccinated across the four studies, of whom 17 178 were included in the primary analysis (8597 receiving ChAdOx1 nCoV-19 and 8581 receiving control vaccine). The data cutoff for these analyses was Dec 7, 2020. 332 NAAT-positive infections met the primary endpoint of symptomatic infection more than 14 days after the second dose. Overall vaccine efficacy more than 14 days after the second dose was 66·7% (95% CI 57·4-74·0), with 84 (1·0%) cases in the 8597 participants in the ChAdOx1 nCoV-19 group and 248 (2·9%) in the 8581 participants in the control group. There were no hospital admissions for COVID-19 in the ChAdOx1 nCoV-19 group after the initial 21-day exclusion period, and 15 in the control group. 108 (0·9%) of 12 282 participants in the ChAdOx1 nCoV-19 group and 127 (1·1%) of 11 962 participants in the control group had serious adverse events. There were seven deaths considered unrelated to vaccination (two in the ChAdOx1 nCov-19 group and five in the control group), including one COVID-19-related death in one participant in the control group. Exploratory analyses showed that vaccine efficacy after a single standard dose of vaccine from day 22 to day 90 after vaccination was 76·0% (59·3-85·9). Our modelling analysis indicated that protection did not wane during this initial 3-month period. Similarly, antibody levels were maintained during this period with minimal waning by day 90 (geometric mean ratio [GMR] 0·66 [95% CI 0·59-0·74]). In the participants who received two standard doses, after the second dose, efficacy was higher in those with a longer prime-boost interval (vaccine efficacy 81·3% [95% CI 60·3-91·2] at ≥12 weeks) than in those with a short interval (vaccine efficacy 55·1% [33·0-69·9] at <6 weeks). These observations are supported by immunogenicity data that showed binding antibody responses more than two-fold higher after an interval of 12 or more weeks compared with an interval of less than 6 weeks in those who were aged 18-55 years (GMR 2·32 [2·01-2·68]). INTERPRETATION: The results of this primary analysis of two doses of ChAdOx1 nCoV-19 were consistent with those seen in the interim analysis of the trials and confirm that the vaccine is efficacious, with results varying by dose interval in exploratory analyses. A 3-month dose interval might have advantages over a programme with a short dose interval for roll-out of a pandemic vaccine to protect the largest number of individuals in the population as early as possible when supplies are scarce, while also improving protection after receiving a second dose. FUNDING: UK Research and Innovation, National Institutes of Health Research (NIHR), The Coalition for Epidemic Preparedness Innovations, the Bill & Melinda Gates Foundation, the Lemann Foundation, Rede D'Or, the Brava and Telles Foundation, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midland's NIHR Clinical Research Network, and AstraZeneca.


Assuntos
Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Esquemas de Imunização , Imunização Secundária , Adolescente , Adulto , Idoso , Formação de Anticorpos , Infecções Assintomáticas , Vacinas contra COVID-19/efeitos adversos , ChAdOx1 nCoV-19 , Humanos , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , SARS-CoV-2/imunologia , Adulto Jovem
16.
Thorax ; 76(1): 73-82, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33214245

RESUMO

INTRODUCTION: Fibroblastic foci represent the cardinal pathogenic lesion in idiopathic pulmonary fibrosis (IPF) and comprise activated fibroblasts and myofibroblasts, the key effector cells responsible for dysregulated extracellular matrix deposition in multiple fibrotic conditions. The aim of this study was to define the major transcriptional programmes involved in fibrogenesis in IPF by profiling unmanipulated myofibroblasts within fibrotic foci in situ by laser capture microdissection. METHODS: The challenges associated with deriving gene calls from low amounts of RNA and the absence of a meaningful comparator cell type were overcome by adopting novel data mining strategies and by using weighted gene co-expression network analysis (WGCNA), as well as an eigengene-based approach to identify transcriptional signatures, which correlate with fibrillar collagen gene expression. RESULTS: WGCNA identified prominent clusters of genes associated with cell cycle, inflammation/differentiation, translation and cytoskeleton/cell adhesion. Collagen eigengene analysis revealed that transforming growth factor ß1 (TGF-ß1), RhoA kinase and the TSC2/RHEB axis formed major signalling clusters associated with collagen gene expression. Functional studies using CRISPR-Cas9 gene-edited cells demonstrated a key role for the TSC2/RHEB axis in regulating TGF-ß1-induced mechanistic target of rapamycin complex 1 activation and collagen I deposition in mesenchymal cells reflecting IPF and other disease settings, including cancer-associated fibroblasts. CONCLUSION: These data provide strong support for the human tissue-based and bioinformatics approaches adopted to identify critical transcriptional nodes associated with the key pathogenic cell responsible for fibrogenesis in situ and further identify the TSC2/RHEB axis as a potential novel target for interfering with excessive matrix deposition in IPF and other fibrotic conditions.


Assuntos
Regulação da Expressão Gênica , Fibrose Pulmonar Idiopática/genética , RNA/genética , Transcriptoma/genética , Células Cultivadas , Fibroblastos/metabolismo , Fibroblastos/patologia , Perfilação da Expressão Gênica , Humanos , Fibrose Pulmonar Idiopática/metabolismo , Fibrose Pulmonar Idiopática/patologia , Pulmão/metabolismo , Pulmão/patologia , Transdução de Sinais , Regulação para Cima
17.
J Cell Sci ; 133(21)2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33033180

RESUMO

The core protease (CP) subcomplex of the 26S proteasome houses the proteolytic active sites and assumes a barrel shape comprised of four co-axially stacked heptameric rings formed by structurally related α- and ß-subunits. CP biogenesis typically begins with the assembly of the α-ring, which then provides a template for ß-subunit integration. In eukaryotes, α-ring assembly is partially mediated by two hetero-dimeric chaperones, termed Pba1-Pba2 (Add66) and Pba3-Pba4 (also known as Irc25-Poc4) in yeast. Pba1-Pba2 initially promotes orderly recruitment of the α-subunits through interactions between their C-terminal HbYX or HbF motifs and pockets at the α5-α6 and α6-α7 interfaces. Here, we identified PBAC5 as a fifth α-ring assembly chaperone in Arabidopsis that directly binds the Pba1 homolog PBAC1 to form a trimeric PBAC5-PBAC1-PBAC2 complex. PBAC5 harbors a HbYX motif that docks with a pocket between the α4 and α5 subunits during α-ring construction. Arabidopsis lacking PBAC5, PBAC1 and/or PBAC2 are hypersensitive to proteotoxic, salt and osmotic stresses, and display proteasome assembly defects. Remarkably, whereas PBAC5 is evolutionarily conserved among plants, sequence relatives are also dispersed within other kingdoms, including a scattered array of fungal, metazoan and oomycete species.


Assuntos
Proteínas de Arabidopsis/genética , Chaperonas Moleculares , Complexo de Endopeptidases do Proteassoma , Arabidopsis , Citoplasma , Chaperonas Moleculares/genética , Complexo de Endopeptidases do Proteassoma/genética
18.
Plant Cell ; 32(12): 3939-3960, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33004618

RESUMO

Phosphatidylinositol 3-phosphate (PI3P) is an essential membrane signature for both autophagy and endosomal sorting that is synthesized in plants by the class III phosphatidylinositol 3-kinase (PI3K) complex, consisting of the VPS34 kinase, together with ATG6, VPS15, and either VPS38 or ATG14 as the fourth subunit. Although Arabidopsis (Arabidopsis thaliana) plants missing the three core subunits are infertile, vps38 mutants are viable but have aberrant leaf, root, and seed development, Suc sensing, and endosomal trafficking, suggesting that VPS38 and ATG14 are nonredundant. Here, we evaluated the role of ATG14 through a collection of clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 and T-DNA insertion mutants disrupting the two Arabidopsis paralogs. atg14a atg14b double mutants were relatively normal phenotypically but displayed pronounced autophagy defects, including reduced accumulation of autophagic bodies and cargo delivery during nutrient stress. Unexpectedly, homozygous atg14a atg14b vps38 triple mutants were viable but showed severely compromised rosette development and reduced fecundity, pollen germination, and autophagy, consistent with a need for both ATG14 and VPS38 to fully actuate PI3P biology. However, the triple mutants still accumulated PI3P, but they were hypersensitive to the PI3K inhibitor wortmannin, indicating that the ATG14/VPS38 component is not essential for PI3P synthesis. Collectively, the ATG14/VPS38 mutant collection now permits the study of plants altered in specific aspects of PI3P biology.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Proteínas Relacionadas à Autofagia/metabolismo , Autofagia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Proteínas Relacionadas à Autofagia/genética , Mutação , Fosfatidilinositol 3-Quinases/genética , Inibidores de Proteínas Quinases/farmacologia , Transporte Proteico , Proteínas de Transporte Vesicular/genética , Wortmanina/farmacologia
19.
Nat Commun ; 11(1): 4659, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938936

RESUMO

The αvß6 integrin plays a key role in the activation of transforming growth factor-ß (TGFß), a pro-fibrotic mediator that is pivotal to the development of idiopathic pulmonary fibrosis (IPF). We identified a selective small molecule αvß6 RGD-mimetic, GSK3008348, and profiled it in a range of disease relevant pre-clinical systems. To understand the relationship between target engagement and inhibition of fibrosis, we measured pharmacodynamic and disease-related end points. Here, we report, GSK3008348 binds to αvß6 with high affinity in human IPF lung and reduces downstream pro-fibrotic TGFß signaling to normal levels. In human lung epithelial cells, GSK3008348 induces rapid internalization and lysosomal degradation of the αvß6 integrin. In the murine bleomycin-induced lung fibrosis model, GSK3008348 engages αvß6, induces prolonged inhibition of TGFß signaling and reduces lung collagen deposition and serum C3M, a marker of IPF disease progression. These studies highlight the potential of inhaled GSK3008348 as an anti-fibrotic therapy.


Assuntos
Butiratos/farmacologia , Fibrose Pulmonar Idiopática/tratamento farmacológico , Integrinas/antagonistas & inibidores , Naftiridinas/farmacologia , Pirazóis/farmacologia , Pirrolidinas/farmacologia , Administração por Inalação , Animais , Antígenos de Neoplasias/metabolismo , Bleomicina/toxicidade , Butiratos/administração & dosagem , Butiratos/metabolismo , Butiratos/farmacocinética , Colágeno/metabolismo , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Humanos , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/patologia , Integrinas/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Naftiridinas/administração & dosagem , Naftiridinas/metabolismo , Naftiridinas/farmacocinética , Pirazóis/administração & dosagem , Pirazóis/metabolismo , Pirazóis/farmacocinética , Pirrolidinas/administração & dosagem , Pirrolidinas/metabolismo , Pirrolidinas/farmacocinética , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Tomografia Computadorizada de Emissão de Fóton Único , Fator de Crescimento Transformador beta/metabolismo , Pesquisa Translacional Biomédica
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