Project description:After myocardial infarction (MI) activation of the immune system and inflammatory mechanisms, among others, can lead to ventricular remodeling and heart failure (HF). Interaction between these systemic alterations and corresponding changes in the heart has not been extensively examined in the setting of chronic ischemia. The main purpose of this study was to investigate alterations in cardiac gene and systemic cytokine profile in mice with post-ischemic HF. Plasma was tested for IgM and IgG anti-heart reactive repertoire and inflammatory cytokines. Heart samples were assayed for gene expression. Ischemic HF significantly increased the levels of serum IgM (by 5.2 fold) and IgG (by 3.6 fold) associated with remarkable content of anti-heart specificity. Comparable increase was observed in levels of circulating pro-inflammatory cytokines, such as IL-1β (3.8x) and TNF-α (6.0x). IFN-gamma was also increased in the MI group by 3.1x. However, IL-4 and IL-10 showed no significant difference between MI and sham groups. Chemokines such as MCP-1 and IL-8 were enhanced in the plasma of infarcted mice. We identified 2079 well annotated unigenes that were significantly regulated by the post-ischemic HF. Complement activation and immune response was among the most up-regulated processes. Interestingly, 21 out of the 101 quantified unigenes involved in inflammatory response were significantly up-regulated and none were down-regulated. These data indicate that post-ischemic heart remodeling is accompanied by immune mediated mechanisms that act both systemically and locally. We compared RNA samples extracted from whole hearts of control and infarcted mice samples by analyzing hybridization to AECOM 32k mouse microarrays (http://microarray1k.aecom.yu.edu/) spotted with Operon version 3.0 70-mer oligonucleotides. The hybridization protocol, the slide type and the scanner settings were uniform throughout the entire experiment to minimize the technical noise. Control (sham) and infarcted red-labeled heart samples were hybridized against an in-house prepared green-labeled universal mouse reference.
Project description:After myocardial infarction (MI) activation of the immune system and inflammatory mechanisms, among others, can lead to ventricular remodeling and heart failure (HF). Interaction between these systemic alterations and corresponding changes in the heart has not been extensively examined in the setting of chronic ischemia. The main purpose of this study was to investigate alterations in cardiac gene and systemic cytokine profile in mice with post-ischemic HF. Plasma was tested for IgM and IgG anti-heart reactive repertoire and inflammatory cytokines. Heart samples were assayed for gene expression. Ischemic HF significantly increased the levels of serum IgM (by 5.2 fold) and IgG (by 3.6 fold) associated with remarkable content of anti-heart specificity. Comparable increase was observed in levels of circulating pro-inflammatory cytokines, such as IL-1β (3.8x) and TNF-α (6.0x). IFN-gamma was also increased in the MI group by 3.1x. However, IL-4 and IL-10 showed no significant difference between MI and sham groups. Chemokines such as MCP-1 and IL-8 were enhanced in the plasma of infarcted mice. We identified 2079 well annotated unigenes that were significantly regulated by the post-ischemic HF. Complement activation and immune response was among the most up-regulated processes. Interestingly, 21 out of the 101 quantified unigenes involved in inflammatory response were significantly up-regulated and none were down-regulated. These data indicate that post-ischemic heart remodeling is accompanied by immune mediated mechanisms that act both systemically and locally.
Project description:To establish changes in cardiac transcription profiles brought about by heart failure we collected myocardial samples from patients undergoing cardiac transplantation whose failure arises from different etiologies (e.g. idiopathic dilated cardiomyopathy, ischemic cardiomyopathy, alcoholic cardiomyopathy, valvular cardiomyopathy, and hypertrophic cardiomyopathy) and from "normal" organ donors whose hearts cannot be used for transplants. The transcriptional profile of the mRNA in these samples will be measured with gene array technology. Changes in transcriptional profiles can be correlated with the physiologic profile of heart-failure hearts acquired at the time of transplantation. Keywords: other
Project description:Heart failure is a leading cause of cardiovascular mortality with limited options for treatment. We used 18 month-old apolipoprotein E (apoE)- deficient mice as a model of atherosclerosis-induced heart failure to analyze whether the anti-ischemic drug ranolazine could retard the progression of heart failure. The study showed that 2 months of ranolazine treatment improved cardiac function of 18 month-old apoE-deficient mice with symptoms of heart failure as assessed by echocardiography. To identify changes in cardiac gene expression induced by treatment with ranolazine a microarray study was performed with heart tissue from failing hearts relative to ranolazine-treated and healthy control hearts. The microarray approach identified heart failure-specific genes that were normalized during treatment with the anti-ischemic drug ranolazine. Microarray gene expression profiling was performed with heart tissue isolated from (i) untreated 18 month-old apoE-deficient mice with heart failure relative to (ii) 18 month-old apoE-deficient mice treated for two months with the anti-ischemic drug ranolazine (200 mg/kg), and (iii) age-matched non-transgenic C57BL/6J (B6) control mice.
Project description:In response to heart failure (HF), the heart reacts by repressing adult genes and expressing fetal genes, thereby returning to a more fetal-like gene profile. To identify genes involved in this process, we carried out transcriptional analysis on murine hearts at different stages of development and adult mice with HF. Our screen identified 5-oxoprolinase (OPLAH), a member of the -Glutamyl cycle, that functions by scavenging 5-oxoproline. OPLAH depletion occurred as a result of cardiac injury, leading to elevated 5-oxoproline and oxidative stress, whereas OPLAH overexpression improved cardiac function after ischemic injury. In HF patients we observed elevated plasma 5-oxoproline levels, which were associated with a worse clinical outcome. Understanding and modulating fetal-like genes in the failing heart may lead to potential novel diagnostic, prognostic and therapeutic options in HF.
Project description:To establish changes in cardiac transcription profiles brought about by heart failure we collected myocardial samples from patients undergoing cardiac transplantation whose failure arises from different etiologies (e.g. idiopathic dilated cardiomyopathy, ischemic cardiomyopathy, alcoholic cardiomyopathy, valvular cardiomyopathy, and hypertrophic cardiomyopathy) and from "normal" organ donors whose hearts cannot be used for transplants. The transcriptional profile of the mRNA in these samples will be measured with gene array technology. Changes in transcriptional profiles can be correlated with the physiologic profile of heart-failure hearts acquired at the time of transplantation. Keywords: other
Project description:Heart failure is a leading cause of cardiovascular mortality with limited options for treatment. We analyzed whether the anti-ischemic drug ranolazine could retard the progression of heart failure in an experimental model of heart failure induced by 6 months of chronic pressure overload. The study showed that 2 months of ranolazine treatment improved cardiac function of aortic constricted C57BL/6J (B6) mice with symptoms of heart failure as assessed by echocardiography. The microarray gene expression study of heart tissue from failing hearts relative to ranolazine-treated and healthy control hearts identified heart failure-specific genes that were normalized during treatment with the anti-ischemic drug ranolazine. Microarray gene expression profiling was performed with heart tissue isolated from three study groups: (i) untreated 10 month-old C57BL/6J (B6) mice with heart failure induced by 6 months of abdominal aortic constriction (AAC), (ii) 10 month-old B6 mice with 6 months of AAC and two months of treatment with the anti-ischemic drug ranolazine (200 mg/kg), and (iii) age-matched, untreated, sham-operated B6 control mice.
Project description:Lysosomes are at the epicenter of cellular processes critical for inflammasome activation in macrophages, including autophagy and lipid metabolism. Inflammasome activation and IL1-beta secretion are implicated in atherogenesis, ischemic cardiac injury and resultant heart failure; however, little is known about the role of macrophage lysosome function in regulating these processes. We hypothesized that macrophages exhibit lysosome dysfunction in heart failure due to ischemic injury, and that augmentation of macrophage lysosomal biogenesis via macrophage-specific overexpression of transcription factor EB (mf-TFEB) would attenuate ischemic remodeling by modulating macrophage inflammatory responses. In both mice subject to ischemia-reperfusion injury, and human heart tissue from patients with ischemic cardiomyopathy, we find evidence of lysosome insufficiency and autophagic impairment, respectively. Mf-TFEB overexpression significantly attenuated post-IR adverse left ventricular remodeling at 4 weeks without affecting scar size. Mf-TFEB overexpression reduced the relative amounts of pro-inflammatory macrophage populations in the myocardium. RNA sequencing of flow-sorted cardiac macrophages post-IR confirmed that TFEB stimulated a lysosomal transcriptional program in macrophages, and upregulated key targets involved in lysosomal lipid metabolism, which we show are critical for inflammasome suppression. Both TFEB-dependent inflammasome suppression and effects on post-IR remodeling were independent of autophagy. Our findings suggest that TFEB reprograms macrophage lysosomal lipid metabolism to attenuate inflammasome activity and protect against post-ischemic cardiac remodeling and simultaneously shift our understanding of how autophagy and lipid metabolism impact acute inflammation.
Project description:Heart failure is a leading cause of cardiovascular mortality with limited options for treatment. We used 18 month-old apolipoprotein E (apoE)- deficient mice as a model of atherosclerosis-induced heart failure to analyze whether the anti-ischemic drug ranolazine could retard the progression of heart failure. The study showed that 2 months of ranolazine treatment improved cardiac function of 18 month-old apoE-deficient mice with symptoms of heart failure as assessed by echocardiography. To identify changes in cardiac gene expression induced by treatment with ranolazine a microarray study was performed with heart tissue from failing hearts relative to ranolazine-treated and healthy control hearts. The microarray approach identified heart failure-specific genes that were normalized during treatment with the anti-ischemic drug ranolazine.
Project description:Coronavirus disease 2019 (COVID-19) is a viral pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 is predominantly defined by respiratory symptoms, but cardiac complications including arrhythmias, heart failure, and viral myocarditis are also prevalent. Although the systemic ischemic and inflammatory responses caused by COVID-19 can detrimentally affect cardiac function, the direct impact of SARS-CoV-2 infection on human cardiomyocytes is not well understood.