RESUMO
BACKGROUND: Tissue ischemia can arise in response to numerous physiologic and pathologic conditions. The cellular response to decreased perfusion, most notably a decrease in glucose and oxygen, is important for cellular survival. In response to oxygen deprivation or hypoxia, one of the key response elements is hypoxia inducible factor (HIF) and a key protein induced by hypoxia is vascular endothelial growth factor (VEGF). Under hypoxia, we and others have reported an increase in the half-life of VEGF and other hypoxia related mRNAs including MYC and CYR61; however, the mediator of this response has yet to be identified. For this study, we sought to determine if HIF-mediated transcriptional activity is involved in the mRNA stabilization induced by hypoxia. METHODS: HEK293T or C6 cells were cultured in either normoxic or hypoxic (1% oxygen) conditions in the presence of 1 g/L glucose for all experiments. Pharmacological treatments were used to mimic hypoxia (desferroxamine, dimethyloxaloglutamate, CoCl2), inhibit mitochondrial respiration (rotenone, myxothiazol), scavenge reactive oxygen species (ROS; ebselen), or generate mitochondrial ROS (antimycin A). siRNAs were used to knock down components of the HIF transcriptional apparatus. mRNA half-life was determined via actinomycin D decay and real time PCR and western blotting was used to determine mRNA and protein levels respectively. RESULTS: Treatment of HEK293T or C6 cells with hypoxic mimetics, desferroxamine, dimethyloxaloglutamate, or CoCl2 showed similar induction of HIF compared to hypoxia treatment, however, in contrast to hypoxia, the mimetics caused no significant increase in VEGF, MYC or CYR61 mRNA half-life. Knockdown of HIF-alpha or ARNT via siRNA also had no effect on hypoxic mRNA stabilization. Interestingly, treatment of HEK293T cells with the mitochondrial inhibitors rotenone and myxothiazol, or the glutathione peroxidase mimetic ebselen did prevent the hypoxic stabilization of VEGF, MYC, and CYR61, suggesting a role for mtROS in the process. Additionally, treatment with antimycin A, which has been shown to generate mtROS, was able to drive the normoxic stabilization of these mRNAs. CONCLUSION: Overall these data suggest that hypoxic mRNA stabilization is independent of HIF transcriptional activity but requires mtROS.
Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Mitocôndrias/metabolismo , Estabilidade de RNA/genética , Espécies Reativas de Oxigênio/metabolismo , Animais , Hipóxia Celular/genética , Células HEK293 , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Transcrição GênicaRESUMO
Objective. To determine whether living in a family with medical financial hardship decreases children's access to health care. Methods. We identified children aged 4 to 17 years from the 2013 to 2018 National Health Interview Surveys. Medical financial hardship was defined as living in a family where one or more family members had problems paying medical bills in the past 12 months. Results. Of 53 483 children in the analysis, 19% were exposed to medical financial hardship. This was adversely associated with children's health status and health care use, especially greater odds of delaying care (odds ratio [OR] = 5.28; 95% confidence interval [CI] = 4.51-6.19) and having unmet health care needs (OR = 4.43; 95% CI = 4.00-4.91). Conclusions. One fifth of children live in families experiencing medical financial hardship, and this exposure is adversely correlated with child health outcomes even controlling for established measures of socioeconomic status, such as family income, health insurance coverage, and need-based program participation.
Assuntos
Saúde da Criança/estatística & dados numéricos , Efeitos Psicossociais da Doença , Estresse Financeiro/epidemiologia , Gastos em Saúde/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , Feminino , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Humanos , Seguro Saúde/estatística & dados numéricos , Masculino , Pobreza , Fatores Socioeconômicos , Estados Unidos/epidemiologiaRESUMO
PURPOSE: To provide a prototypical patient narrative of the cardiac rehabilitation (CR) experience for providers and prospective patients using narrative analysis. METHODS: Qualitative interviews with 17 CR patients from a previous study regarding their experiences, reasons, and motivations related to engagement in CR were analyzed using narrative inquiry. Interviews were previously analyzed and coded for recurring themes, and these themes were implemented in an exploratory narrative inquiry to craft a CR patient "story." A hypothetical composite character representing the varied experiences of CR patients interviewed was developed, and a patient story was constructed that reflected on an initial cardiac event, time during rehabilitation, difficult experiences, social interactions, and personal values and accomplishments. RESULTS: The CR patient narrative is presented for use in CR recruitment and programming materials, and in provider education. CONCLUSION: The narrative analysis comprehensively provides patients with an amalgam of patient experiences and can be used by providers to gain an understanding of CR patient experiences. Further research is needed to determine whether use of the resulting narrative analysis within the referral process and/or programming could increase participation and engagement.
Assuntos
Reabilitação Cardíaca/psicologia , Cardiopatias/reabilitação , Motivação , Participação do Paciente , Preferência do Paciente , Feminino , Cardiopatias/psicologia , Humanos , Relações Interpessoais , Masculino , Pessoa de Meia-Idade , Narração , Avaliação das Necessidades , Participação do Paciente/métodos , Participação do Paciente/psicologia , Pesquisa Qualitativa , Resultado do TratamentoRESUMO
AIMS: Intracardiac injection of recombinant EphrinA1-Fc immediately following coronary artery ligation in mice reduces infarct size in both reperfused and non-reperfused myocardium, but the cellular alterations behind this phenomenon remain unknown. MAIN METHODS: Herein, 10 wk-old B6129SF2/J male mice were exposed to acute ischemia/reperfusion (30minI/24hrsR) injury immediately followed by intracardiac injection of either EphrinA1-Fc or IgG-Fc. After 24â¯h of reperfusion, sections of the infarct margin in the left ventricle were imaged via transmission electron microscopy, and mitochondrial function was assessed in both permeabilized fibers and isolated mitochondria, to examine mitochondrial structure, function, and energetics in the early stages of repair. KEY FINDINGS: At a structural level, EphrinA1-Fc administration prevented the I/R-induced loss of sarcomere alignment and mitochondrial organization along the Z disks, as well as disorganization of the cristae and loss of inter-mitochondrial junctions. With respect to bioenergetics, loss of respiratory function induced by I/R was prevented by EphrinA1-Fc. Preservation of cardiac bioenergetics was not due to changes in mitochondrial JH2O2 emitting potential, membrane potential, ADP affinity, efficiency of ATP production, or activity of the main dehydrogenase enzymes, suggesting that EphrinA1-Fc indirectly maintains respiratory function via preservation of the mitochondrial network. Moreover, these protective effects were lost in isolated mitochondria, further emphasizing the importance of the intact cardiomyocyte ultrastructure in mitochondrial energetics. SIGNIFICANCE: Collectively, these data suggest that intracardiac injection of EphrinA1-Fc protects cardiac function by preserving cardiomyocyte structure and mitochondrial bioenergetics, thus emerging as a potential therapeutic strategy in I/R injury.