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1.
Br J Gen Pract ; 74(741): e275-e282, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38164588

RESUMO

BACKGROUND: Australia has one of the highest incidences of colorectal cancer (CRC) worldwide. The Australian National Bowel Cancer Screening Program (NBCSP) is a best-practice, organised screening programme, but uptake is low (40.9%) and increasing participation could reduce morbidity and mortality associated with CRC. Endorsement by GPs is strongly associated with increasing screening uptake. AIM: This study (SMARTscreen) aimed to test whether a multi-intervention short message service (SMS) sent by general practices to 50-60-year-old patients who were due to receive the NBCSP kit would increase NBCSP uptake, by comparing it with usual care. DESIGN AND SETTING: A stratified cluster randomised controlled trial was undertaken, involving 21 Australian general practices in Western Victoria, Australia. METHOD: For intervention practices, people due to receive the NBCSP kit within a 6-month study period were sent an SMS just before receiving the kit. The SMS included a personalised message from the person's general practice endorsing the kit, a motivational narrative video, an instructional video, and a link to more information. Control practices continued with usual care, comprising at-home testing with a faecal immunochemical test (FIT) through the NBCSP. The primary outcome was the between-arm percentage difference in uptake of FIT screening within 12 months from randomisation, which was estimated using generalised linear model regression. RESULTS: In total, 39.2% (1143/2914) of people in 11 intervention practices and 23.0% (583/2537) of people in 10 control practices had a FIT result in their electronic health records - a difference of 16.5% (95% confidence interval = 2.02 to 30.9). CONCLUSION: The SMS intervention increased NBCSP kit return in 50-60-year-old patients in general practice. This finding informed a larger trial - SMARTERscreen - to test this intervention in a broader Australian population.


Assuntos
Neoplasias Colorretais , Medicina Geral , Humanos , Pessoa de Meia-Idade , Austrália/epidemiologia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/prevenção & controle , Neoplasias Colorretais/epidemiologia , Detecção Precoce de Câncer , Medicina de Família e Comunidade , Programas de Rastreamento
2.
Trials ; 24(1): 723, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37957680

RESUMO

BACKGROUND: Australia persistently has one of the highest rates of colorectal cancer (CRC) in the world. Australia's National Bowel Cancer Screening Program (NBCSP) sends a biennial Faecal Immunochemical Test (FIT)-the 'NBCSP kit'-to everyone eligible for the programme between 50 and 74 years old; however, participation in the programme is low, especially in the 50- to 60-year-old age group. Our previous efficacy trial ('SMARTscreen') demonstrated an absolute increase in uptake of 16.5% (95% confidence interval = 2.02-30.9%) for people sent an SMS with motivational and instructional videos, from their general practice prior to receiving their NBCSP kit, compared to those receiving usual care. Building on the strengths of the SMARTscreen trial and addressing limitations, the 'SMARTERscreen' trial will test the effect on participation in the NBCSP of sending either an SMS only or an SMS with online video material to general practice patients due to receive their NBCSP compared to 'usual care'. METHODS: SMARTERscreen is a three-arm stratified cluster randomised controlled trial involving 63 general practices in two states in Australia. Eligible patients are patients who are aged 49-60 years and due to receive their NBCSP kit within the next 2 weeks during the intervention period. General practices will be equally randomised to three trial arms (21:21:21, estimated average 260 patients/practice). The two interventions include (i) an SMS with an encouraging message from their general practice or (ii) the same SMS with weblinks to additional motivational and instructional videos. The control arm will receive 'usual care'. Using the intention-to-treat approach, primary analysis will estimate the three pair-wise between-arm differences in the proportion of eligible patients who participate in the NBCSP within 6 months of when their kit is sent, utilising screening data from the Australian National Cancer Screening Register (NCSR). Patient intervention adherence to the interventions will also be evaluated. Findings will be incorporated into the Policy1-Bowel microsimulation model to estimate the long-term health benefits and cost-effectiveness of the interventions. DISCUSSION: SMARTERscreen will provide high-level evidence determining whether an SMS or an SMS with web-based material sent to general practice patients prior to receiving their NBCSP kit increases participation in bowel cancer screening. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12623000036617. Registered on 13 January 2023. Trial URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=385119&isClinicalTrial=False.


Assuntos
Neoplasias Colorretais , Medicina Geral , Humanos , Pessoa de Meia-Idade , Idoso , Austrália , Detecção Precoce de Câncer , Intestinos , Neoplasias Colorretais/diagnóstico , Programas de Rastreamento , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
J Extracell Vesicles ; 12(7): e12332, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37353884

RESUMO

The release of growth factors, cytokines and extracellular matrix modifiers by activated platelets is an important step in the process of healthy wound healing. Extracellular vesicles (EVs) released by activated platelets carry this bioactive cargo in an enriched form, and may therefore represent a potential therapeutic for the treatment of delayed wound healing, such as chronic wounds. While EVs show great promise in regenerative medicine, their production at clinical scale remains a critical challenge and their tolerability in humans is still to be fully established. In this work, we demonstrate that Ligand-based Exosome Affinity Purification (LEAP) chromatography can successfully isolate platelet EVs (pEVs) of clinical grade from activated platelets, which retain the regenerative properties of the parent cell. LEAP-isolated pEVs display the expected biophysical features of EV populations and transport essential proteins in wound healing processes, including insulin growth factor (IGF) and transforming growth factor beta (TGF-ß). In vitro studies show that pEVs induce proliferation and migration of dermal fibroblasts and increase dermal endothelial cells' angiogenic potential, demonstrating their wound healing potential. pEV treatment activates the ERK and Akt signalling pathways within recipient cells. In a first-in-human, double-blind, placebo-controlled, phase I clinical trial of healthy volunteer adults, designed primarily to assess safety in the context of wound healing, we demonstrate that injections of LEAP-purified pEVs in formulation buffer are safe and well tolerated (Plexoval II study, ACTRN12620000944932). As a secondary objective, biological activity in the context of wound healing rate was assessed. In this cohort of healthy participants, in which the wound bed would not be expected to be deficient in the bioactive cargo that pEVs carry, all wounds healed rapidly and completely and no difference in time to wound closure of the treated and untreated wounds was observed at the single dose tested. The outcomes of this study evidence that pEVs manufactured through the LEAP process can be injected safely in humans as a potential wound healing treatment, and warrant further study in clinical trials designed expressly to assess therapeutic efficacy in patients with delayed or disrupted wound healing.


Assuntos
Vesículas Extracelulares , Transplante de Células-Tronco Hematopoéticas , Adulto , Humanos , Plaquetas/metabolismo , Células Endoteliais , Vesículas Extracelulares/metabolismo , Cicatrização/fisiologia
4.
Eur Heart J ; 43(45): 4739-4750, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36200607

RESUMO

AIMS: In response to pro-fibrotic signals, scleraxis regulates cardiac fibroblast activation in vitro via transcriptional control of key fibrosis genes such as collagen and fibronectin; however, its role in vivo is unknown. The present study assessed the impact of scleraxis loss on fibroblast activation, cardiac fibrosis, and dysfunction in pressure overload-induced heart failure. METHODS AND RESULTS: Scleraxis expression was upregulated in the hearts of non-ischemic dilated cardiomyopathy patients, and in mice subjected to pressure overload by transverse aortic constriction (TAC). Tamoxifen-inducible fibroblast-specific scleraxis knockout (Scx-fKO) completely attenuated cardiac fibrosis, and significantly improved cardiac systolic function and ventricular remodelling, following TAC compared to Scx+/+ TAC mice, concomitant with attenuation of fibroblast activation. Scleraxis deletion, after the establishment of cardiac fibrosis, attenuated the further functional decline observed in Scx+/+ mice, with a reduction in cardiac myofibroblasts. Notably, scleraxis knockout reduced pressure overload-induced mortality from 33% to zero, without affecting the degree of cardiac hypertrophy. Scleraxis directly regulated transcription of the myofibroblast marker periostin, and cardiac fibroblasts lacking scleraxis failed to upregulate periostin synthesis and secretion in response to pro-fibrotic transforming growth factor ß. CONCLUSION: Scleraxis governs fibroblast activation in pressure overload-induced heart failure, and scleraxis knockout attenuated fibrosis and improved cardiac function and survival. These findings identify scleraxis as a viable target for the development of novel anti-fibrotic treatments.


Assuntos
Insuficiência Cardíaca , Remodelação Ventricular , Camundongos , Animais , Fibrose , Miofibroblastos/metabolismo , Cardiomegalia/metabolismo , Fibroblastos/metabolismo , Insuficiência Cardíaca/patologia , Miocárdio/patologia , Camundongos Endogâmicos C57BL
5.
Trials ; 23(1): 31, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35022080

RESUMO

BACKGROUND: Increasing participation in the Australian National Bowel Cancer Screening Program (NBCSP) is the most efficient and cost-effective way of reducing mortality associated with colorectal cancer by detecting and treating early-stage disease. Currently, only 44% of Australians aged 50-74 years complete the NBCSP. This efficacy trial aims to test whether this SMS intervention is an effective method for increasing participation in the NBCSP. Furthermore, a process evaluation will explore the barriers and facilitators to sending the SMS from general practice. METHODS: We will recruit 20 general practices in the western region of Victoria, Australia to participate in a cluster randomised controlled trial. General practices will be randomly allocated with a 1:1 ratio to either a control or intervention group. Established general practice software will be used to identify patients aged 50 to 60 years old who are due to receive a NBCSP kit in the next month. The SMS intervention includes GP endorsement and links to narrative messages about the benefits of and instructions on how to complete the NBCSP kit. It will be sent from intervention general practices to eligible patients prior to receiving the NBCSP kit. We require 1400 eligible patients to provide 80% power with a two-sided 5% significance level to detect a 10% increase in CRC screening participation in the intervention group compared to the control group. Our primary outcome is the difference in the proportion of eligible patients who completed a faecal occult blood test (FOBT) between the intervention and control group for up to 12 months after the SMS was sent, as recorded in their electronic medical record (EMR). A process evaluation using interview data collected from general practice staff (GP, practice managers, nurses) and patients will explore the feasibility and acceptability of sending and receiving a SMS to prompt completing a NBCSP kit. DISCUSSION: This efficacy trial will provide initial trial evidence of the utility of an SMS narrative intervention to increase participation in the NBCSP. The results will inform decisions about the need for and design of a larger, multi-state trial of this SMS intervention to determine its cost-effectiveness and future implementation. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12620001020976 . Registered on 17 October 2020.


Assuntos
Neoplasias Colorretais , Detecção Precoce de Câncer , Neoplasias Colorretais/diagnóstico , Humanos , Programas de Rastreamento , Pessoa de Meia-Idade , Sangue Oculto , Vitória
6.
Cell Death Dis ; 12(12): 1105, 2021 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-34824192

RESUMO

Systemic hypoxia is a common element in most perinatal emergencies and is a known driver of Bnip3 expression in the neonatal heart. Bnip3 plays a prominent role in the evolution of necrotic cell death, disrupting ER calcium homeostasis and initiating mitochondrial permeability transition (MPT). Emerging evidence suggests a cardioprotective role for the prostaglandin E1 analog misoprostol during periods of hypoxia, but the mechanisms for this protection are not completely understood. Using a combination of mouse and cell models, we tested if misoprostol is cardioprotective during neonatal hypoxic injury by altering Bnip3 function. Here we report that hypoxia elicits mitochondrial-fragmentation, MPT, reduced ejection fraction, and evidence of necroinflammation, which were abrogated with misoprostol treatment or Bnip3 knockout. Through molecular studies we show that misoprostol leads to PKA-dependent Bnip3 phosphorylation at threonine-181, and subsequent redistribution of Bnip3 from mitochondrial Opa1 and the ER through an interaction with 14-3-3 proteins. Taken together, our results demonstrate a role for Bnip3 phosphorylation in the regulation of cardiomyocyte contractile/metabolic dysfunction, and necroinflammation. Furthermore, we identify a potential pharmacological mechanism to prevent neonatal hypoxic injury.


Assuntos
Proteínas 14-3-3/metabolismo , Cardiopatias/tratamento farmacológico , Proteínas de Membrana/metabolismo , Misoprostol/uso terapêutico , Proteínas Mitocondriais/metabolismo , Ocitócicos/uso terapêutico , Animais , Modelos Animais de Doenças , Humanos , Misoprostol/farmacologia , Ocitócicos/farmacologia , Ratos , Transfecção
8.
Wound Repair Regen ; 29(4): 667-677, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34076932

RESUMO

Heart disease with attendant cardiac fibrosis kills more patients in developed countries than any other disease, including cancer. We highlight the recent literature on factors that activate and also deactivate cardiac fibroblasts. Activation of cardiac fibroblasts results in myofibroblasts phenotype which incorporates aSMA to stress fibres, express ED-A fibronectin, elevated PDGFRα and are hypersecretory ECM components. These cells facilitate both acute wound healing (infarct site) and chronic cardiac fibrosis. Quiescent fibroblasts are associated with normal myocardial tissue and provide relatively slow turnover of the ECM. Deactivation of activated myofibroblasts is a much less studied phenomenon. In this context, SKI is a known negative regulator of TGFb1 /Smad signalling, and thus may share functional similarity to PPARγ activation. The discovery of SKI's potent anti-fibrotic role, and its ability to deactivate and/or myofibroblasts is featured and contrasted with PPARγ. While myofibroblasts are typically recruited from pools of potential precursor cells in a variety of organs, the importance of activation of resident cardiac fibroblasts has been recently emphasised. Myofibroblasts deposit ECM components at an elevated rate and contribute to both systolic and diastolic dysfunction with attendant cardiac fibrosis. A major knowledge gap exists as to specific proteins that may signal for fibroblast deactivation. As SKI may be a functionally pluripotent protein, we suggest that it serves as a scaffold to proteins other than R-Smads and associated Smad signal proteins, and thus its anti-fibrotic effects may extend beyond binding R-Smads. While cardiac fibrosis is causal to heart failure, the treatment of cardiac fibrosis is hampered by the lack of availability of effective pharmacological anti-fibrotic agents. The current review will provide an overview of work highlighting novel factors which cause fibroblast activation and deactivation to underscore putative therapeutic avenues for improving disease outcomes in cardiac patients with fibrosed hearts.


Assuntos
Antifibróticos , Cicatrização , Fibroblastos/patologia , Fibrose , Humanos , Miocárdio/patologia , Miofibroblastos/patologia
9.
Cell Tissue Res ; 385(3): 753-768, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34057573

RESUMO

Fibroblast growth factor 2 (FGF2), produced as high (Hi-) and low (Lo-) molecular weight isoforms, is implicated in cardiac response to injury. The role of endogenous FGF2 isoforms during chronic stress is not well defined. We investigated the effects of endogenous Hi-FGF2 in a mouse model of simulated pressure-overload stress achieved by transverse aortic constriction (TAC) surgery. Hi-FGF2 knockout mice, expressing only Lo-FGF2, FGF2(Lo), and wild-type mice, FGF2(WT), expressing both Hi-FGF2 and Lo-FGF2, were used. By echocardiography, a decline in systolic function was observed in FGF2(WT) but not FGF2(Lo) mice compared to corresponding sham-operated animals at 4-8 weeks post-TAC surgery. TAC surgery increased markers of myocardial stress/damage including B-type natriuretic peptide (BNP) and the pro-cell death protein BCL2/adenovirus E1B 19 kDa protein-interacting protein-3 (Bnip3) in FGF2(WT) but not FGF2(Lo) mice. In FGF2(Lo) mice, cardiac levels of activated FGF receptor 1 (FGFR1), and downstream signals, including phosphorylated mTOR and p70S6 kinase, were elevated post-TAC. Finally, NR1D1 (nuclear receptor subfamily 1 group D member 1), implicated in cardioprotection from pressure-overload stress, was downregulated or upregulated in the presence or absence, respectively, of Hi-FGF2 expression, post-TAC surgery. In wild-type cardiomyocyte cultures, endothelin-1 (added to simulate pressure-overload signals) caused NR1D1 downregulation and BNP upregulation, similar to the effect of TAC surgery on the FGF2(WT) mice. The NR1D1 agonist SR9009 prevented BNP upregulation, simulating post-TAC findings in FGF2(Lo) mice. We propose that elimination of Hi-FGF2 is cardioprotective during pressure-overload by increasing FGFR1-associated signaling and NR1D1 expression.


Assuntos
Pressão Sanguínea/genética , Fator 2 de Crescimento de Fibroblastos/uso terapêutico , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/metabolismo , Animais , Masculino , Camundongos , Camundongos Knockout , Ratos , Transdução de Sinais
10.
Methods Mol Biol ; 2299: 171-179, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34028743

RESUMO

Two-dimensional cell culture is the primary method employed for proof-of-concept studies in most molecular biology labs. While immortalized cell lines are convenient and easy to maintain for extended periods in vitro, their inability to accurately represent genuine cell physiology-or pathophysiology-presents a challenge for drug discovery, as most results are not viable for the transition to clinical trial. The use of primary cells is a more biologically relevant approach to this issue; however, simulating in vitro what is observed in vivo is exigent at best. Primary cardiac fibroblasts are particularly difficult to maintain in a quiescent state, due to their innate phenotypic plasticity, and sensitivity to mechanical and biochemical stimulus. As conventional cell culture methods do not consider these factors, here we describe a method that limits environmental input (i.e., mechanical, nutritional, hormonal) to extend the physiological cardiac fibroblast phenotype in vitro.


Assuntos
Miócitos Cardíacos/citologia , Miofibroblastos/citologia , Cultura Primária de Células/métodos , Actinas/metabolismo , Animais , Diferenciação Celular , Células Cultivadas , Humanos , Fenômenos Mecânicos , Camundongos , Modelos Biológicos , Miócitos Cardíacos/metabolismo , Miofibroblastos/metabolismo , Fenótipo
11.
Basic Res Cardiol ; 116(1): 25, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33847835

RESUMO

We have previously shown that overexpression of SKI, an endogenous TGF-ß1 repressor, deactivates the pro-fibrotic myofibroblast phenotype in the heart. We now show that SKI also functions independently of SMAD/TGF-ß signaling, by activating the Hippo tumor-suppressor pathway and inhibiting the Transcriptional co-Activator with PDZ-binding motif (TAZ or WWTR1). The mechanism(s) by which SKI targets TAZ to inhibit cardiac fibroblast activation and fibrogenesis remain undefined. A rat model of post-myocardial infarction was used to examine the expression of TAZ during acute fibrogenesis and chronic heart failure. Results were then corroborated with primary rat cardiac fibroblast cell culture performed both on plastic and on inert elastic substrates, along with the use of siRNA and adenoviral expression vectors for active forms of SKI, YAP, and TAZ. Gene expression was examined by qPCR and luciferase assays, while protein expression was examined by immunoblotting and fluorescence microscopy. Cell phenotype was further assessed by functional assays. Finally, to elucidate SKI's effects on Hippo signaling, the SKI and TAZ interactomes were captured in human cardiac fibroblasts using BioID2 and mass spectrometry. Potential interactors were investigated in vitro to reveal novel mechanisms of action for SKI. In vitro assays on elastic substrates revealed the ability of TAZ to overcome environmental stimuli and induce the activation of hypersynthetic cardiac myofibroblasts. Further cell-based assays demonstrated that SKI causes specific proteasomal degradation of TAZ, but not YAP, and shifts actin cytoskeleton dynamics to inhibit myofibroblast activation. These findings were supported by identifying the bi-phasic expression of TAZ in vivo during post-MI remodeling and fibrosis. BioID2-based interactomics in human cardiac fibroblasts suggest that SKI interacts with actin-modifying proteins and with LIM Domain-containing protein 1 (LIMD1), a negative regulator of Hippo signaling. Furthermore, we found that LATS2 interacts with TAZ, whereas LATS1 does not, and that LATS2 knockdown prevented TAZ downregulation with SKI overexpression. Our findings indicate that SKI's capacity to regulate cardiac fibroblast activation is mediated, in part, by Hippo signaling. We postulate that the interaction between SKI and TAZ in cardiac fibroblasts is arbitrated by LIMD1, an important intermediary in focal adhesion-associated signaling pathways. This study contributes to the understanding of the unique physiology of cardiac fibroblasts, and of the relationship between SKI expression and cell phenotype.


Assuntos
Fibroblastos/metabolismo , Insuficiência Cardíaca/metabolismo , Via de Sinalização Hippo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas com Domínio LIM/metabolismo , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Remodelação Ventricular , Animais , Células Cultivadas , Modelos Animais de Doenças , Fibroblastos/patologia , Fibrose , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas com Domínio LIM/genética , Masculino , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/patologia , Miofibroblastos/metabolismo , Miofibroblastos/patologia , Fenótipo , Proteínas Proto-Oncogênicas/genética , Ratos , Ratos Sprague-Dawley , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional/genética , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional/metabolismo
12.
Cell Signal ; 76: 109802, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33017619

RESUMO

Cardiac fibroblast activation to hyper-synthetic myofibroblasts following a pathological stimulus or in response to a substrate with increased stiffness may be a key tipping point for the evolution of cardiac fibrosis. Cardiac fibrosis per se is associated with progressive loss of heart pump function and is a primary contributor to heart failure. While TGF-ß is a common cytokine stimulus associated with fibroblast activation, a druggable target to quell this driver of fibrosis has remained an elusive therapeutic goal due to its ubiquitous use by different cell types and also in the signaling complexity associated with SMADs and other effector pathways. More recently, mechanical stimulus of fibroblastic cells has been revealed as a major point of activation; this includes cardiac fibroblasts. Further, the complexity of TGF-ß signaling has been offset by the discovery of members of the SKI family of proteins and their inherent anti-fibrotic properties. In this respect, SKI is a protein that may bind a number of TGF-ß associated proteins including SMADs, as well as signaling proteins from other pathways, including Hippo. As SKI is also known to directly deactivate cardiac myofibroblasts to fibroblasts, this mode of action is a putative candidate for further study into the amelioration of cardiac fibrosis. Herein we provide a synthesis of this topic and highlight novel candidate pathways to explore in the treatment of cardiac fibrosis.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Fibroblastos , Mecanotransdução Celular , Miocárdio , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose , Via de Sinalização Hippo , Humanos , Miocárdio/metabolismo , Miocárdio/patologia
13.
Int J Chron Obstruct Pulmon Dis ; 15: 1135-1142, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547001

RESUMO

Purpose: Chronic obstructive pulmonary disease (COPD) is one of the leading causes of death worldwide. Impaired lung function is associated with heightened risk for death, cardiovascular events, and COPD exacerbations. However, it is unclear if forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) differ in predictive value. Patients and Methods: Data from 16,485 participants in the Study to Understand Mortality and Morbidity (SUMMIT) in COPD were analyzed. Patients were grouped into quintiles for each lung function parameter (FEV1 %predicted, FVC %predicted, FEV1/FVC). The four highest quintiles (Q2-Q5) were compared to the lowest (Q1) to assess their relationship with all-cause mortality, cardiovascular events, and moderate-to-severe and severe exacerbations. Cox-regression was used, adjusted for age, sex, ethnicity, body-mass index, smoking status, previous exacerbations, cardiovascular disease, treatment, and modified Medical Research Council dyspnea score. Results: Compared to Q1 (<53.5% FEV1 predicted), increasing FEV1 quintiles (Q2 53.5-457.5% predicted, Q3 57.5-461.6% predicted, Q4 61.6-465.8% predicted, and Q5 ≥65.8%) were all associated with significantly decreased all-cause mortality (20% (4-34%), 28% (13-40%), 23% (7-36%), and 30% (15-42%) risk reduction, respectively). In contrast, a significant risk reduction (21% (4-35%)) was seen only between Q1 and Q5 quintiles of FVC. Neither FEV1 nor FVC was associated with cardiovascular risk. Increased FEV1 and FEV1/FVC quintiles were also associated with the reduction of moderate-to-severe and severe exacerbations while, surprisingly, the highest FVC quintile was related to the heightened exacerbation risk (28% (8-52%) risk increase). Conclusion: Our results suggest that FEV1 is a stronger predictor for all-cause mortality than FVC in moderate COPD patients with heightened cardiovascular risk and that subjects with moderate COPD have very different risks.


Assuntos
Doenças Cardiovasculares , Doença Pulmonar Obstrutiva Crônica , Doenças Cardiovasculares/diagnóstico , Volume Expiratório Forçado , Humanos , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Testes de Função Respiratória , Capacidade Vital
14.
Bioorg Med Chem ; 28(6): 115344, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-32051094

RESUMO

Proprotein convertase (PC) subtilisin kexin type 9 (PCSK9) inhibits the clearance of low density lipoprotein (LDL) cholesterol from plasma by directly interacting with the LDL receptor (LDLR). As the interaction promotes elevated plasma LDL cholesterol levels and a predisposition to cardiovascular disease (CVD), it has attracted much interest as a therapeutic target. While anti-PCSK9 monoclonal antibodies have been successful in the treatment of hypercholesteremia by decreasing CVD risk, their high cost and a requirement for injection have prohibited widespread use. The advent of an orally bioavailable small molecule inhibitor of the PCSK9-LDLR interaction is an attractive alternative, however efforts have been tempered as the binding interface is unfavourable for binding by small organic molecules. Despite its challenging nature, we report herein the discovery of compound 3f as a small molecule inhibitor of PCSK9. The kinase inhibitor nilotinib emerged from a computational screen that was applied to identify compounds that may bind to a cryptic groove within PCSK9 and proximal to the LDLR-binding interface. A subsequent in vitro PCSK9-LDLR binding assay established that nilotinib was a bona fide but modest inhibitor of the interaction (IC50 = 9.8 µM). Through multiple rounds of medicinal chemistry, 3f emerged as a lead-like molecule by demonstrating disruption of the PCSK9-LDLR interaction at nanomolar levels in vitro (IC50 = 537 nM) with no inhibitory activity (IC50 > 10 µM) against a small panel of kinases. Compound 3f restored LDL uptake by liver cells at sub-micromolar levels and demonstrated excellent bioavailability when delivered subcutaneously in mice. Most significantly, compound 3f lowered total cholesterol levels in the plasma of wild-type mice, thereby providing proof-of-concept that the notion of a small molecule inhibitor against PCSK9 is therapeutically viable.


Assuntos
Inibidores de PCSK9 , Receptores de LDL/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Sítios de Ligação/efeitos dos fármacos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos , Feminino , Células Hep G2 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Estrutura Molecular , Pró-Proteína Convertase 9/deficiência , Pró-Proteína Convertase 9/metabolismo , Receptores de LDL/metabolismo , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade
16.
Sci Rep ; 9(1): 12889, 2019 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501457

RESUMO

Primary cardiac fibroblasts are notoriously difficult to maintain for extended periods of time in cell culture, due to the plasticity of their phenotype and sensitivity to mechanical input. In order to study cardiac fibroblast activation in vitro, we have developed cell culture conditions which promote the quiescent fibroblast phenotype in primary cells. Using elastic silicone substrata, both rat and mouse primary cardiac fibroblasts could be maintained in a quiescent state for more than 3 days after isolation and these cells showed low expression of myofibroblast markers, including fibronectin extracellular domain A, non-muscle myosin IIB, platelet-derived growth factor receptor-alpha and alpha-smooth muscle actin. Gene expression was also more fibroblast-like vs. that of myofibroblasts, as Tcf21 was significantly upregulated, while Fn1-EDA, Col1A1 and Col1A2 were markedly downregulated. Cell culture conditions (eg. serum, nutrient concentration) are critical for the control of temporal fibroblast proliferation. We propose that eliminating mechanical stimulus and limiting the nutrient content of cell culture media can extend the quiescent nature of primary cardiac fibroblasts for physiological analyses in vitro.


Assuntos
Técnicas de Cultura de Células/métodos , Miofibroblastos/citologia , Animais , Proliferação de Células , Masculino , Ratos
17.
BMJ Open Respir Res ; 6(1): e000431, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31258919

RESUMO

Rationale: Systemic levels of C reactive protein (CRP), surfactant protein D (SPD), fibrinogen, soluble receptor of activated glycogen end-product (sRAGE) and club cell protein 16 (CC-16) have been associated with chronic obstructive pulmonary disease (COPD) outcomes. However, they require validation in different cohorts. Objectives: Relate systemic levels of those proteins to forced expiratory volume in 1 s (FEV1) decline, exacerbations, hospitalisations and mortality in COPD patients (FEV1 of ≥50 and ≤70% predicted) and heightened cardiovascular risk in a substudy of the Study to Understand Mortality and MorbidITy trial. Methods: Participants were randomised to daily inhalations of placebo, vilanterol 25 µg (VI), fluticasone furoate 100 µg (FF) or their combination (VI 25/FF 100) and followed quarterly until 1000 deaths in the overall 16 485 participants occurred. Biomarker blood samples were available from 1673 patients. The FEV1 decline (mL/year), COPD exacerbations, hospitalisations and death were determined. Associations between biomarker levels and outcomes were adjusted by age and gender. Results: Systemic levels of CC-16, CRP, sRAGE, SPD and fibrinogen did not relate to baseline FEV1, FEV1 decline, exacerbations or hospitalisations. Fibrinogen and CRP were related to mortality over a median follow-up of 2.3 years. Only the CC-16 changed with study therapy (VI, FF and FF/VI, p<0.01) at 3 months. Conclusions: In COPD, systemic levels of CC-16, CRP, sRAGE, SPD and fibrinogen were not associated with FEV1 decline, exacerbations or hospitalisations. These results cast doubts about the clinical usefulness of the systemic levels of these proteins as surrogate markers of these COPD outcomes. The study confirms that CRP and fibrinogen are associated with increased risk of death in patients with COPD. Trial registration number: NCT01313676.


Assuntos
Broncodilatadores/administração & dosagem , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Administração por Inalação , Idoso , Androstadienos/administração & dosagem , Álcoois Benzílicos/administração & dosagem , Biomarcadores/sangue , Proteína C-Reativa/análise , Clorobenzenos/administração & dosagem , Quimioterapia Combinada , Estudos de Viabilidade , Feminino , Fibrinogênio/análise , Seguimentos , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/sangue , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/mortalidade , Proteína D Associada a Surfactante Pulmonar/sangue , Receptor para Produtos Finais de Glicação Avançada/sangue , Exacerbação dos Sintomas , Resultado do Tratamento , Uteroglobina/sangue
18.
Adv Exp Med Biol ; 1132: 35-41, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31037622

RESUMO

Cardiac muscle (the myocardium) is a unique arrangement of atria and ventricles that are spatially and electrically separated by a fibrous border. The spirally-arranged myocytes in both left and right ventricles are tethered by the component molecules of the cardiac extracellular matrix (ECM), including fibrillar collagen types I and III. Loss of normal arrangement of the ECM with either too little (as is observed in acute myocardial infarction) or too much (cardiac fibrosis in chronic post-myocardial infarction) is the primary contributor to cardiac dysfunction and heart failure. Matricellular proteins exist as non-structural signaling moieties in the ECM, and in the context of cardiac hypertrophy and heart failure, secreted 90 kDa periostin protein has attracted intense scrutiny during the past decade. Secreted periostin is now recognized for its important role in ECM development and maturation, as well as cellular adhesion. The novel mechanisms of periostin function include its role as a mediator of cell-to-matrix signaling, cell survival, and epithelial-mesenchymal transition (EMT). A number of recent studies have examined the hypothesis that periostin is a major contributor to ECM remodeling in the heart, and a number of very recent studies underscore its important role. This review examines recent developments in the mechanisms of periostin function in the normal heart and vasculature, and discusses recent advances which underpin its putative role in the development of cardiovascular disease. Periostin expression is very low at baseline in healthy tissues, but is re-expressed in damaged heart and in vessel walls after injury, in activated cardiac myofibroblasts and vascular smooth muscle cells, respectively. For this reason, periostin may be exploited for investigation of mechanisms of cardiac fibrosis , and we speculate that data generated from studies utilizing this approach may shed light on the timing for application of periostin-specific therapies to quell cardiac fibrosis and associated cardiac dysfunction.


Assuntos
Moléculas de Adesão Celular/fisiologia , Infarto do Miocárdio , Miofibroblastos/citologia , Remodelação Ventricular , Proteínas da Matriz Extracelular , Ventrículos do Coração , Humanos , Miocárdio , Fenótipo
19.
Compr Physiol ; 9(1): 75-125, 2018 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-30549015

RESUMO

Cardiovascular disease leading to heart failure (HF) remains a leading cause of morbidity and mortality worldwide. Improved pharmacological and interventional coronary procedures have led to improved outcomes following acute myocardial infarction. This success has translated into an unforeseen increased incidence in HF. This review summarizes the signaling pathways implicated in the transition to HF following cardiac injury. In addition, we provide an update on cell death signaling and discuss recent advances in cardiac fibrosis as an independent event leading to HF. Finally, we discuss cell-based therapies and their possible use to avert the deteriorating nature of HF. © 2019 American Physiological Society. Compr Physiol 9:75-125, 2019.


Assuntos
Insuficiência Cardíaca/metabolismo , Medicina Regenerativa/métodos , Transdução de Sinais , Engenharia Tecidual/métodos , Animais , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/terapia , Humanos , Miocárdio/metabolismo , Miocárdio/patologia
20.
Physiol Rep ; 6(22): e13897, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30488595

RESUMO

Many etiologies of heart disease are characterized by expansion and remodeling of the cardiac extracellular matrix (ECM or matrix) which results in cardiac fibrosis. Cardiac fibrosis is mediated in cardiac fibroblasts by TGF-ß1 /R-Smad2/3 signaling. Matrix component proteins are synthesized by activated resident cardiac fibroblasts known as myofibroblasts (MFB). These events are causal to heart failure with diastolic dysfunction and reduced cardiac filling. We have shown that exogenous Ski, a TGF-ß1 /Smad repressor, localizes in the cellular nucleus and deactivates cardiac myofibroblasts. This deactivation is associated with reduction of myofibroblast marker protein expression in vitro, including alpha smooth muscle actin (α-SMA) and extracellular domain-A (ED-A) fibronectin. We hypothesize that Ski also acutely regulates MMP expression in cardiac MFB. While acute Ski overexpression in cardiac MFB in vitro was not associated with any change in intracellular MMP-9 protein expression versus LacZ-treated controls,exogenous Ski caused elevated MMP-9 mRNA expression and increased MMP-9 protein secretion versus controls. Zymographic analysis revealed increased MMP-9-specific gelatinase activity in myofibroblasts overexpressing Ski versus controls. Moreover, Ski expression was attended by reduced paxillin and focal adhesion kinase phosphorylation (FAK - Tyr 397) versus controls. As myofibroblasts are hypersecretory and less motile relative to fibroblasts, Ski's reduction of paxillin and FAK expression may reflect the relative deactivation of myofibroblasts. Thus, in addition to its known antifibrotic effects, Ski overexpression elevates expression and extracellular secretion/release of MMP-9 and thus may facilitate internal cytoskeletal remodeling as well as extracellular ECM components. Further, as acute TGF-ß1 treatment of primary cardiac MFB is known to cause rapid translocation of Ski to the nucleus, our data support an autoregulatory role for Ski in mediating cardiac ECM accumulation.


Assuntos
Metaloproteinase 9 da Matriz/metabolismo , Miocárdio/citologia , Miofibroblastos/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Actinas/genética , Actinas/metabolismo , Animais , Movimento Celular , Células Cultivadas , Fibronectinas/genética , Fibronectinas/metabolismo , Masculino , Metaloproteinase 9 da Matriz/genética , Miocárdio/metabolismo , Miofibroblastos/fisiologia , Paxilina/genética , Paxilina/metabolismo , Proteínas Proto-Oncogênicas/genética , Ratos , Ratos Sprague-Dawley
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