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Doxorubicin is a commonly used anti-cancer drug used in treating a variety of malignancies. However, a major adverse effect is cardiotoxicity, which is dose dependent and can be either acute or chronic. Doxorubicin causes injury by DNA damage, the formation of free reactive oxygen radicals and induction of apoptosis. Our aim is to induce expression of the multidrug resistance-associated protein 1 (MRP1) in cardiomyocytes derived from human iPS cells (hiPSC-CM), to determine whether this will allow cells to effectively remove doxorubicin and confer cardioprotection. We generated a lentivirus vector encoding MRP1 (LV.MRP1) and validated its function in HEK293T cells and stem cell-derived cardiomyocytes (hiPSC-CM) by quantitative PCR and western blot analysis. The activity of the overexpressed MRP1 was also tested, by quantifying the amount of fluorescent dye exported from the cell by the transporter. We demonstrated reduced dye sequestration in cells overexpressing MRP1. Finally, we demonstrated that hiPSC-CM transduced with LV.MRP1 were protected against doxorubicin injury. In conclusion, we have shown that we can successfully overexpress MRP1 protein in hiPSC-CM, with functional transporter activity leading to protection against doxorubicin-induced toxicity.
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Cardiotoxicidad , Proteínas Asociadas a Resistencia a Múltiples Medicamentos , Miocitos Cardíacos , Humanos , Cardiotoxicidad/prevención & control , Cardiotoxicidad/metabolismo , Cardiotoxicidad/patología , Células HEK293 , Doxorrubicina/farmacologíaRESUMEN
Ghrelin is commonly known as the 'hunger hormone' due to its role in stimulating food intake in humans. However, the roles of ghrelin extend beyond regulating hunger. Our aim was to investigate the ability of ghrelin to protect against hydrogen peroxide (H2O2), a reactive oxygen species commonly associated with cardiac injury. An in vitro model of oxidative stress was developed using H2O2 injured H9c2 cells. Despite lentiviral ghrelin overexpression, H9c2 cell viability and mitochondrial function were not protected following H2O2 injury. We found that H9c2 cells lack expression of the preproghrelin cleavage enzyme prohormone convertase 1 (encoded by PCSK1), required to convert ghrelin to its active form. In contrast, we found that primary rat cardiomyocytes do express PCSK1 and were protected from H2O2 injury by lentiviral ghrelin overexpression. In conclusion, we have shown that ghrelin expression can protect primary rat cardiomyocytes against H2O2, though this effect was not observed in other cell types tested.
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Ghrelina , Peróxido de Hidrógeno , Humanos , Animales , Ratas , Peróxido de Hidrógeno/farmacología , Ghrelina/genética , Ghrelina/metabolismo , Ghrelina/farmacología , Apoptosis , Transducción de Señal , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Especies Reactivas de Oxígeno/farmacología , Miocitos Cardíacos/metabolismoRESUMEN
Lentiviral vectors are a robust gene delivery tool for inducing transgene expression in a variety of cells. They are well suited to facilitate the testing of therapeutic candidate genes in vitro, due to relative ease of packaging and ability to transduce dividing and non-dividing cells. Our goal was to identify a gene that could be delivered to the heart to protect against cancer-therapy-induced cardiotoxicity. We sought to generate a lentivirus construct with a ubiquitous CMV promoter driving expression of B-cell lymphocyte/leukemia 2 gene (Bcl-2), a potent anti-apoptotic gene. Contrary to our aim, overexpression of Bcl-2 induced cell death in the producer HEK293T cells, resulting in failure to produce usable vector titre. This was circumvented by exchanging the CMV promoter to the cardiac-specific NCX1 promoter, leading to the successful production of a lentiviral vector which could induce cardioprotective expression of Bcl-2. In conclusion, reduced expression of Bcl-2 driven by a weaker promoter improved vector yield, and led to the production of functional cardioprotective Bcl-2 in primary cardiomyocytes.
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Cardiotoxicidad , Genes bcl-2 , Vectores Genéticos , Humanos , Células HEK293 , Miocitos Cardíacos , Transgenes , Lentivirus/genética , Vectores Genéticos/genética , Vectores Genéticos/uso terapéuticoRESUMEN
Recombinant adeno-associated viruses (rAAVs) have emerged as one of the most promising gene therapy vectors that have been successfully used in pre-clinical models of heart disease. However, this has not translated well to humans due to species differences in rAAV transduction efficiency. As a result, the search for human cardiotropic capsids is a major contemporary challenge. We used a capsid-shuffled rAAV library to perform directed evolution in human iPSC-derived cardiomyocytes (hiPSC-CMs). Five candidates emerged, with four presenting high sequence identity to AAV6, while a fifth divergent variant was related to AAV3b. Functional analysis of the variants was performed in vitro using hiPSC-CMs, cardiac organoids, human cardiac slices, non-human primate and porcine cardiac slices, as well as mouse heart and liver in vivo. We showed that cell entry was not the best predictor of transgene expression efficiency. The novel variant rAAV.KK04 was the best-performing vector in human-based screening platforms, exceeding the benchmark rAAV6. None of the novel capsids demonstrate a significant transduction of liver in vivo. The range of experimental models used revealed the value of testing for tropism differences under the conditions of human specificity, bona fide, myocardium and cell type of interest.
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Globally, adeno-associated virus (AAV) vectors have been increasingly used for clinical gene therapy trials. In Australia, AAV-based gene therapy is available for hereditary diseases such as retinal dystrophy or spinal muscular atrophy 1 (SMA1). Many preclinical studies have used AAV vectors for gene therapy in models of cardiac disease with outcomes of varying translational potential. However, major barriers to effective and safe therapeutic gene delivery to the human heart remain to be overcome. These include tropism, efficient gene transfer, mitigating off-target gene delivery and avoidance of the host immune response. Developing such an enhanced AAV vector for cardiac gene therapy is of great interest to the field of advanced cardiac therapeutics. In this review, we provide an overview of the approaches currently being employed in the search for cardiac cell-specific AAV capsids, ranging from natural AAVs selected as a result of infection and latency in the heart, to the use of cutting-edge molecular techniques to engineer and select AAVs specific for cardiac cells with the use of high-throughput methods.
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Dependovirus , Técnicas de Transferencia de Gen , Tropismo Viral , Humanos , Dependovirus/fisiología , Vectores GenéticosRESUMEN
Cardioembolic stroke (CS) has emerged as a leading cause of ischaemic stroke (IS); distinguished by thrombi embolising to the brain from cardiac origins; most often from the left atrial appendage (LAA). Contemporary therapeutic options are largely dependent on systemic anticoagulation as a blanket preventative strategy, yet this does not represent a nuanced or personalised solution. Contraindications to systemic anticoagulation create significant unmedicated and high-risk cohorts, leaving these patients at risk of significant morbidity and mortality. Atrial appendage occlusion devices are increasingly used to mitigate stroke risk from thrombi emerging from the LAA in patients ineligible for oral anticoagulants (OACs). Their use, however, is not without risk or significant cost, and does not address the underlying aetiology of thrombosis and CS. Viral vector-based gene therapy has emerged as a novel strategy to target a spectrum of haemostatic disorders, achieving success through the adeno-associated virus (AAV) based therapy of haemophilia. Yet, thrombotic disorders, such as CS, have had limited exploration within the realm of AAV gene therapy approaches-presenting a gap in the literature and an opportunity for further research. Gene therapy has the potential to directly address the cause of CS by localised targeting of the molecular remodelling that serves to promote thrombosis.
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Apéndice Atrial , Fibrilación Atrial , Isquemia Encefálica , Accidente Cerebrovascular Embólico , Accidente Cerebrovascular , Trombosis , Humanos , Accidente Cerebrovascular/genética , Accidente Cerebrovascular/prevención & control , Accidente Cerebrovascular Embólico/complicaciones , Accidente Cerebrovascular Embólico/tratamiento farmacológico , Anticoagulantes/uso terapéutico , Trombosis/etiología , Resultado del TratamientoRESUMEN
Patient experience is positively associated with clinical effectiveness, quality care, and patient safety. This study examines the experience of care of adolescents and young adult (AYA) cancer patients from Australia and the United States, allowing a comparison of patient experiences in the context of different national models of cancer care delivery. Participants (n = 190) were aged 15-29 years and received cancer treatment from 2014 to 2019. Australians (n = 118) were recruited nationally by health care professionals. U.S. participants (n = 72) were recruited nationally via social media. The survey included demographic and disease variables, and questions regarding medical treatment, information and support provision, care coordination, and satisfaction across the treatment pathway. Sensitivity analyses examined the possible contribution of age and gender. Most patients from both countries were satisfied or very satisfied with their medical treatment (chemotherapy, radiotherapy, and surgery). There were significant differences between countries in the provision of fertility preservation services, age-appropriate communication, and psychosocial support. Our findings suggest when a national system of oversight with both state and federal funding is implemented, as is the case in Australia but not in the United States, significantly more AYAs with cancer receive age-appropriate information and support services, and improved access to specialist services such as fertility care. A national approach with government funding and centralized accountability appears to be associated with substantial benefits for the well-being of AYAs undergoing cancer treatment.
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Preservación de la Fertilidad , Neoplasias , Adolescente , Humanos , Adulto Joven , Australia , Preservación de la Fertilidad/psicología , Neoplasias/terapia , Neoplasias/psicología , Atención al Paciente , Estados Unidos , AdultoRESUMEN
Sinoatrial node dysfunction can manifest as bradycardia, leading to symptoms of syncope and sudden cardiac death. Electronic pacemakers are the current standard of care but are limited due to a lack of biological chronotropic control, cost of revision surgeries, and risk of lead- and device-related complications. We therefore aimed to develop a biological alternative to electronic devices by using a clinically relevant gene therapy vector to demonstrate conversion of cardiomyocytes into sinoatrial node-like cells in an in vitro context. Neonatal rat ventricular myocytes were transduced with recombinant adeno-associated virus vector 6 encoding either hTBX18 or green fluorescent protein and maintained for 3 weeks. At the endpoint, qPCR, Western blot analysis and immunocytochemistry were used to assess for reprogramming into pacemaker cells. Cell morphology and Arclight action potentials were imaged via confocal microscopy. Compared to GFP, hTBX18-transduced cells showed that hTBX18, HCN4 and Cx45 were upregulated. Cx43 was significantly downregulated, while sarcomeric α-actinin remained unchanged. Cardiomyocytes transduced with hTBX18 acquired the tapering morphology of native pacemaker cells, as compared to the block-like, striated appearance of ventricular cardiomyocytes. Analysis of the action potentials showed phase 4 depolarization and a significant decrease in the APD50 of the hTBX18-transduced cells. We have demonstrated that rAAV-hTBX18 gene transfer to ventricular myocytes results in morphological, molecular, physiological, and functional changes, recapitulating the pacemaker phenotype in an in vitro setting. The generation of these induced pacemaker-like cells using a clinically relevant vector opens new prospects for biological pacemaker development.
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Miocitos Cardíacos , Nodo Sinoatrial , Potenciales de Acción , Animales , Relojes Biológicos/fisiología , Dependovirus , Vectores Genéticos/genética , Miocitos Cardíacos/metabolismo , RatasRESUMEN
Gene therapy is making significant impact on a modest, yet growing, number of human diseases. Justifiably, the preferred viral vector for clinical use is that based on recombinant adeno-associated virus (rAAV). There is a need to scale up rAAV vector production with the transition from pre-clinical models to human application. Standard production methods based on the adherent cell type (HEK293) are limited in scalability and other methods, such as those based on the baculovirus and non-adherent insect cell (Sf9) system, have been pursued as an alternative to increase rAAV production. In this study, we compare these two production methods for cardiotropic rAAVs. Transduction efficiency for both production methods was assessed in primary cardiomyocytes, human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), and in mice following systemic delivery. We found that the rAAV produced by the traditional HEK293 method out-performed vector produced using the baculovirus/Sf9 system in vitro and in vivo. This finding provides a potential caveat for vector function when using the baculovirus/Sf9 production system and underscores the need for thorough assessment of vector performance when using diverse rAAV production methods.
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Células Madre Pluripotentes Inducidas , Animales , Baculoviridae/genética , Dependovirus/genética , Vectores Genéticos/genética , Células HEK293 , Humanos , RatonesRESUMEN
OBJECTIVE: Most adolescents and young adults (AYA) can expect to survive a cancer diagnosis and treatment, but all will be left with the potential of long-term negative effects that can impact their ability to reach their full potential in life. Understanding aspects of psychological, functional, and social health and well-being outcomes, is pivotal for optimising long-term well-being. METHODS: We completed a systematic review of longitudinal studies reporting outcomes after anti-cancer treatment for Adolescents and Young Adults diagnosed between the age of 12-29 years according to established systematic review processes. The protocol was registered with PROSPERO (ID: CRD 42020203116). RESULTS: Thirteen reports from 10 studies met eligibility criteria representing 17,645 individuals (50.3% female, mean age at diagnosis 22 years, and 26 years at last, follow up). Eleven reports were from eight quantitative studies that relied on self-report surveys and two were qualitative studies. Psychological outcomes were reported to improve over time, as were functional health outcomes, although reported health behaviours were inconsistent between studies. Neurocognitive deficits were reported to affect the ability to return to work and impacts on fertility and sexuality were sustained over time. CONCLUSIONS: While some outcomes for AYA are reported to improve over time, particularly for physical functioning, and anxiety and depression, the long-term impact of cancer on many important domains remains largely unknown. Specifically, the evidence to understand what changes occur over time, and when, remains underdeveloped.
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Supervivientes de Cáncer , Neoplasias , Adolescente , Adulto , Ansiedad/psicología , Supervivientes de Cáncer/psicología , Niño , Femenino , Humanos , Estudios Longitudinales , Masculino , Neoplasias/psicología , Neoplasias/terapia , Calidad de Vida/psicología , Encuestas y Cuestionarios , Adulto JovenRESUMEN
BACKGROUND: Cardiac arrhythmias are a leading cause of death. The mainstay method for diagnosing arrhythmias (eg, atrial fibrillation) and cardiac conduction disorders (eg, prolonged corrected QT interval [QTc]) is by using 12-lead electrocardiography (ECG). Handheld 12-lead ECG devices are emerging in the market. In tandem with emerging technology options, evaluations of device usability should go beyond validation of the device in a controlled laboratory setting and assess user perceptions and experiences, which are crucial for successful implementation in clinical practice. OBJECTIVE: This study aimed to evaluate clinician and patient perceptions and experiences, regarding the usability of a handheld 12-lead ECG device compared to a conventional 12-lead ECG machine, and generalizability of this user-centered approach. METHODS: International Organization for Standardization Guidelines on Usability and the Technology Acceptance Model were integrated to form the framework for this study, which was conducted in outpatient clinics and cardiology wards at Westmead Hospital, New South Wales, Australia. Each patient underwent 2 ECGs (1 by each device) in 2 postures (supine and standing) acquired in random sequence. The times taken by clinicians to acquire the first ECG (efficiency) using the devices were analyzed using linear regression. Electrocardiographic parameters (QT interval, QTc interval, heart rate, PR interval, QRS interval) and participant satisfaction surveys were collected. Device reliability was assessed by evaluating the mean difference of QTc measurements within ±15 ms, intraclass correlation coefficient, and level of agreement of the devices in detecting atrial fibrillation and prolonged QTc. Clinicians' perceptions and feedback were assessed with semistructured interviews based on the Technology Acceptance Model. RESULTS: A total of 100 patients (age: mean 57.9 years, SD 15.2; sex: male: n=64, female n=36) and 11 clinicians (experience acquiring ECGs daily or weekly 10/11, 91%) participated, and 783 ECGs were acquired. Mean differences in QTc measurements of both handheld and conventional devices were within ±15 ms with high intraclass correlation coefficients (range 0.90-0.96), and the devices had a good level of agreement in diagnosing atrial fibrillation and prolonged QTc (κ=0.68-0.93). Regardless of device, QTc measurements when patients were standing were longer duration than QTc measurements when patients were supine. Clinicians' ECG acquisition times improved with usage (P<.001). Clinicians reported that device characteristics (small size, light weight, portability, and wireless ECG transmission) were highly desired features. Most clinicians agreed that the handheld device could be used for clinician-led mass screening with enhancement in efficiency by increasing user training. Regardless of device, patients reported that they felt comfortable when they were connected to the ECG devices. CONCLUSIONS: Reliability and usability of the handheld 12-lead ECG device were comparable to those of a conventional ECG machine. The user-centered evaluation approach helped us identify remediable action to improve the efficiency in using the device and identified highly desirable device features that could potentially help mass screening and remote assessment of patients. The approach could be applied to evaluate and better understand the acceptability and usability of new medical devices.
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Anthracyclines are associated with risk of significant dose-dependent cardiotoxicity. Conventional heart failure therapies have neither ameliorated declining cardiac function nor addressed the underlying cause. Gene therapy may confer long-term cardioprotection by rendering the heart resistant to anthracyclines after 1 treatment, although the optimal therapeutic target remains to be elucidated. Recombinant adeno-associated virus is now clinically approved for the treatment of lipoprotein lipase deficiency, spinal muscular atrophy, and hereditary transthyretin amyloidosis. High-throughput methods allow selection of recombinant adeno-associated virus capsids that facilitate efficient gene delivery to specific target cells. Vector safety is enhanced by incorporating cardiac-specific promoters into vector design and localizing delivery to reduce off-target risk. Any cardioprotective transgene may bear a degree of risk as they may play as yet unknown roles, which require careful assessment using clinically relevant models. The innovative technologies outlined here make gene therapy a promising proof of principle, with potential further application to nonanthracycline chemotherapeutics.
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PURPOSE: In the last decade, interest in gene therapy as a therapeutic technology has increased, largely driven by an exciting yet modest number of successful applications for monogenic diseases. Setbacks in the use of gene therapy for cardiac disease have motivated efforts to develop vectors with enhanced tropism for the heart and more efficient delivery methods. Although monogenic diseases are the logical target, cardiac arrhythmias represent a group of conditions amenable to gene therapy because of focal targets (biological pacemakers, nodal conduction, or stem cell-related arrhythmias) or bystander effects on cells not directly transduced because of electrical coupling. METHODS: This review provides a contemporary narrative of the field of gene therapy for experimental cardiac arrhythmias, including those associated with stem cell transplant. Recent articles published in the English language and available through the PubMed database and other prominent literature are discussed. FINDINGS: The promise of gene therapy has been realized for a handful of monogenic diseases and is actively being pursued for cardiac applications in preclinical models. With improved vectors, it is likely that cardiac disease will also benefit from this technology. Cardiac arrhythmias, whether inherited or acquired, are a group of conditions with a potentially lower threshold for phenotypic correction and as such hold unique potential as targets for cardiac gene therapy. IMPLICATIONS: There has been a proliferation of research on the potential of gene therapy for cardiac arrhythmias. This body of investigation forms a strong basis on which further developments, particularly with viral vectors, are likely to help this technology progress along its translational trajectory.
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Arritmias Cardíacas/terapia , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Terapia Genética/métodos , Vectores Genéticos , HumanosRESUMEN
BACKGROUND: Atrial fibrillation (AF) and other arrhythmias are prevalent and often encountered by general practitioners (GPs). In response to the growing prevalence and to assist practitioners in the diagnosis and management of AF, the Cardiac Society of Australia & New Zealand and Heart Foundation of Australia published the first Australian AF Guidelines in 2018. We aimed to examine (a) the proportion of GPs who performed any form of AF screening and identify the methods they applied, (b) GPs' awareness of the AF Guidelines and approaches to arrhythmia screening, (c) the roles of conventional 12-lead ECG and mobile health devices, and (d) GPs' confidence in ECG interpretation and need for training. METHODS: A cross-sectional online survey titled "GPs Screen their patients for Atrial Fibrillation and othEr aRrhythmia (GPSAFER)" was conducted from October 2018 to March 2019. The participants were recruited via various GP networks across Australia. Ethics approval was granted by The University of Sydney. RESULTS: A total of 463 surveys were completed. Many GPs (394/463, 85.1%, 95% CI 81.5-88.2%) performed some forms of AF screening and applied at least one AF screening method, most frequently pulse palpation (389/463, 84.0%). Some (299/463, 64.6%) GPs considered assessing their patients for other arrhythmias (237/299, 79.3% for complete heart block and 236/299, 78.9% for long-QT). Most GPs (424/463, 91.6%) were not using mobile ECG devices in their practice but some (147/463, 31.7%) were contemplating it. One third (175/463, 37.8%) of GPs were aware of the Australian AF Guidelines; those aware were more likely to perform AF screening (98.9% vs 76.7%, p < 0.001). Factors significantly and positively associated with AF screening were "awareness of the AF Guidelines" (p < 0.001), "number of years working in general practice" (p < 0.001), and "confidence in ECG interpretation of AF" (p = 0.003). Most GPs reported that they were very or extremely confident in interpreting AF (381/463, 82.3%) and complete heart block (266/463, 57.5%). Many GPs (349/463, 75.4%) would like to receive online ECG interpretation training. CONCLUSIONS: Assessment of arrhythmias is common in general practice and GPs are open to further training in ECG interpretation and using mobile ECG devices to aid their clinical practice. Increasing awareness of AF Guidelines and improving confidence in ECG interpretation may increase AF screening.
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Arritmias Cardíacas/diagnóstico , Fibrilación Atrial/diagnóstico , Médicos Generales , Atención Primaria de Salud , Australia , Estudios Transversales , Diagnóstico Diferencial , Electrocardiografía , Encuestas de Atención de la Salud , Humanos , Tamizaje MasivoRESUMEN
Differences between mouse and human hearts pose a significant limitation to the value of small animal models when predicting vector behavior following recombinant adeno-associated viral (rAAV) vector-mediated cardiac gene therapy. Hence, sheep have been adopted as a preclinical animal, as they better model the anatomy and cardiac physiological processes of humans. There is, however, no comprehensive data on the shedding profile of rAAV in sheep following intracoronary delivery, so as to understand biosafety risks in future preclinical and clinical applications. In this study, sheep received intracoronary delivery of rAAV serotypes 2/6 (2 × 1012 vg), 2/8, and 2/9 (1 × 1013 vg) at doses previously administered in preclinical and clinical trials. This was followed by assessment over 96 h to examine vector shedding in urine, feces, nasal mucus, and saliva samples. Vector genomes were detected via real-time quantitative PCR in urine and feces up to 48 and 72 h post vector delivery, respectively. Of these results, functional vector particles were only detected via a highly sensitive infectious replication assay in feces samples up to 48 h following vector delivery. We conclude that rAAV-mediated gene transfer into sheep hearts results in low-grade shedding of non-functional vector particles for all excreta samples, except in the case of feces, where functional vector particles are present up to 48 h following vector delivery. These results may be used to inform containment and decontamination guidelines for large animal dealings, and to understand the biosafety risks associated with future preclinical and clinical uses of rAAV.
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Dependovirus/genética , Vectores Genéticos , Esparcimiento de Virus , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Cateterismo , Vasos Coronarios , Dependovirus/inmunología , Dependovirus/fisiología , Vectores Genéticos/administración & dosificación , Vectores Genéticos/inmunología , Células HeLa , Humanos , Inyecciones Intraarteriales , Masculino , Infecciones por Parvoviridae/inmunología , Infecciones por Parvoviridae/orina , Infecciones por Parvoviridae/virología , Reacción en Cadena en Tiempo Real de la Polimerasa , Ovinos , Replicación ViralRESUMEN
Metabolic liver diseases are attractive gene therapy targets that necessitate reconstitution of enzymatic activity in functionally complex biochemical pathways. The levels of enzyme activity required in individual hepatocytes and the proportion of the hepatic cell mass that must be gene corrected for therapeutic benefit vary in a disease-dependent manner that is difficult to predict. While empirical evaluation is inevitably required, useful insights can nevertheless be gained from knowledge of disease pathophysiology and theoretical approaches such as mathematical modeling. Urea cycle defects provide an excellent example. Building on a previously described one-compartment model of the urea cycle, we have constructed a two-compartment model that can simulate liver-targeted gene therapy interventions using the computational program Mathematica. The model predicts that therapeutically effective reconstitution of ureagenesis will correlate most strongly with the proportion of the hepatic cell mass transduced rather than the level of enzyme-encoding transgene expression achieved in individual hepatocytes. Importantly, these predictions are supported by experimental data in mice and human genotype/phenotype correlations. The most notable example of the latter is ornithine transcarbamylase deficiency (X-linked) where impairment of ureagenesis in male and female patients is closely simulated by the one- and two-compartment models, respectively. Collectively, these observations support the practical value of mathematical modeling in evaluation of the disease-specific gene transfer challenges posed by complex metabolic phenotypes.
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Terapia Genética , Modelos Biológicos , Trastornos Innatos del Ciclo de la Urea/genética , Trastornos Innatos del Ciclo de la Urea/terapia , Carbamoil Fosfato/metabolismo , Simulación por Computador , Humanos , Enfermedad por Deficiencia de Ornitina Carbamoiltransferasa/genéticaRESUMEN
Nonalcoholic steatohepatitis (NASH) is a metabolic liver disease that progresses from simple steatosis to the disease state of inflammation and fibrosis. Previous studies suggest that apoptosis and necroptosis may contribute to the pathogenesis of NASH, based on several murine models. However, the mechanisms underlying the transition of simple steatosis to steatohepatitis remain unclear, because it is difficult to identify when and where such cell deaths begin to occur in the pathophysiological process of NASH. In the present study, our aim is to investigate which type of cell death plays a role as the trigger for initiating inflammation in fatty liver. By establishing a simple method of discriminating between apoptosis and necrosis in the liver, we found that necrosis occurred prior to apoptosis at the onset of steatohepatitis in the choline-deficient, ethionine-supplemented (CDE) diet model. To further investigate what type of necrosis is involved in the initial necrotic cell death, we examined the effect of necroptosis and ferroptosis inhibition by administering inhibitors to wild-type mice in the CDE diet model. In addition, necroptosis was evaluated using mixed lineage kinase domain-like protein (MLKL) knockout mice, which is lacking in a terminal executor of necroptosis. Consequently, necroptosis inhibition failed to block the onset of necrotic cell death, while ferroptosis inhibition protected hepatocytes from necrotic death almost completely, and suppressed the subsequent infiltration of immune cells and inflammatory reaction. Furthermore, the amount of oxidized phosphatidylethanolamine, which is involved in ferroptosis pathway, was increased in the liver sample of the CDE diet-fed mice. These findings suggest that hepatic ferroptosis plays an important role as the trigger for initiating inflammation in steatohepatitis and may be a therapeutic target for preventing the onset of steatohepatitis.
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Ferroptosis , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/patología , Animales , Apoptosis/efectos de los fármacos , Tetracloruro de Carbono/toxicidad , Cromanos/farmacología , Citocinas/metabolismo , Dieta , Etionina , Ferroptosis/efectos de los fármacos , Hepatitis/inmunología , Hepatitis/metabolismo , Hepatocitos/citología , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Quelantes del Hierro/farmacología , Hígado/citología , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Necroptosis/efectos de los fármacos , Necrosis , Enfermedad del Hígado Graso no Alcohólico/inducido químicamente , Enfermedad del Hígado Graso no Alcohólico/metabolismoRESUMEN
INTRODUCTION: Simple and scalable strategies are needed to improve 'out-of-hospital' support and management for people living with cardiovascular disease (CVD) and respiratory disease. Text messaging via mobile phones has been shown to be effective in helping promote lifestyle change and is supported by quantitative and qualitative evidence. The aim of this study is to test the effectiveness and implementation of a 6-month text messaging support programme for people with CVD and respiratory disease as an addition to cardiac and pulmonary outpatient rehabilitation. METHODS AND ANALYSIS: Pragmatic randomised controlled trial (n=310) to test the effectiveness of a 6-month text message support programme on clinical outcomes in people with CVD and chronic respiratory disease who are attending outpatient cardiac and pulmonary rehabilitation. The study includes a nested process evaluation to inform scalability and implementation across settings. The intervention group will receive a text message support programme comprising five messages per week for 26 weeks and the control group will continue with standard care. The primary outcome is exercise capacity (6 min walk distance). Secondary outcomes include clinical measures (proportion of people meeting the Australian guideline-recommended blood pressure and cholesterol targets), lifestyle outcomes (smoking rates, achievement of national guidelines for nutrition and physical activity), quality of life, mood (Hospital Anxiety and Depression Scale), medication adherence and attendance at and completion of rehabilitation. ETHICS AND DISSEMINATION: Primary ethics approval was received from the Sydney Local Health District Hospital Human Research Ethics Committee and associated Governance committees at sites. Results will be disseminated via the usual scientific forums including peer-reviewed publications and presentations at international conferences. At its conclusion, the study will determine the effectiveness and implementation of a simple programme that aims to improve health outcomes and attendance at rehabilitation for people with CVD and chronic respiratory disease. TRIAL REGISTRATION NUMBER: ACTRN12616001167459.
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Enfermedades Cardiovasculares/terapia , Cumplimiento de la Medicación , Educación del Paciente como Asunto/métodos , Enfermedades Respiratorias/terapia , Envío de Mensajes de Texto , Australia , Presión Sanguínea , Teléfono Celular , Enfermedad Crónica , Dieta , Ejercicio Físico , Humanos , Estilo de Vida , Motivación , Ensayos Clínicos Pragmáticos como Asunto , Calidad de Vida , Sistemas Recordatorios , Autocuidado/métodosRESUMEN
OBJECTIVE: We aimed to evaluate the effects on depression scores of a lifestyle-focused cardiac support programme delivered via mobile phone text messaging among patients with coronary heart disease (CHD). DESIGN: Substudy and secondary analysis of a parallel-group, single-blind randomised controlled trial of patients with CHD. SETTING: A tertiary hospital in Sydney, Australia. INTERVENTION: The Tobacco, Exercise and dieT MEssages programme comprised four text messages per week for 6 months that provided education, motivation and support on diet, physical activity, general cardiac education and smoking, if relevant. The programme did not have any specific mental health component. OUTCOMES: Depression scores at 6 months measured using the Patient Health Questionnaire-9 (PHQ-9). Treatment effect across subgroups was measured using log-binomial regression model for the binary outcome (depressed/not depressed, where depressed is any score of PHQ-9 ≥5) with treatment, subgroup and treatment by subgroup interaction as fixed effects. RESULTS: Depression scores at 6 months were lower in the intervention group compared with the control group, mean difference 1.9 (95% CI 1.5 to 2.4, p<0.0001). The frequency of mild or greater depressive symptoms (PHQ-9 scores≥5) at 6 months was 21/333 (6.3%) in the intervention group and 86/350 (24.6%) in the control group (relative risk (RR) 0.26, 95% CI 0.16 to 0.40, p<0.001). This proportional reduction in depressive symptoms was similar across groups defined by age, sex, education, body mass index, physical activity, current smoking, current drinking and history of depression, diabetes and hypertension. In particular, the rates of PHQ-9 ≥5 among people with a history of depression were 4/44 (9.1%) vs 29/62 (46.8%) in intervention vs control (RR 0.19, 95% CI 0.07 to 0.51, p<0.001), and were 17/289 (5.9%) vs 57/288 (19.8%) among others (RR 0.30, 95% CI 0.18 to 0.50, p<0.001). CONCLUSIONS: Among people with CHD, a cardiac support programme delivered via mobile phone text messaging was associated with fewer symptoms of mild-to-moderate depression at 6 months in the treatment group compared with controls. TRIAL REGISTRATION NUMBER: ACTRN12611000161921.