Project description:While human organoid systems have provided a powerful platform in modeling diseases caused by genetic disorders, non-genetic factors, such as lifestyle and environment, are the largest attributable factors to devastating diseases like cardiovascular disease (CVD), the leading cause of death worldwide. Specifically, myocardial infarction (MI) (i.e., heart attack) makes up ~8.5% of CVD and is a common cause of heart failure with a 40% five-year mortality after the first MI. This highlights an urgent need to develop relevant human heart failure models for drug development. This is further evidenced by the disappointing performance of heart failure drugs in clinical trials during the last decade, which has been partially attributed to the distinct differences between human patient hearts and animal heart failure models. Here, we combined major non-genetic causal factors of MI with our previously established cardiac organoids to create the first human organoid model of cardiac infarction. In particular, we leveraged the diffusion limitation in 3D microtissues to recreate the nutrient diffusion gradient across infarcted hearts (i.e., infarct-border-remote zones) in human cardiac organoids to induce cardiac organotypic response to infarction. This enabled the recapitulation of major MI hallmarks in human cardiac organoids at the transcriptomic, structural and functional level.
Project description:While human organoid systems have provided a powerful platform in modeling diseases caused by genetic disorders, non-genetic factors, such as lifestyle and environment, are the largest attributable factors to devastating diseases like cardiovascular disease (CVD), the leading cause of death worldwide. Specifically, myocardial infarction (MI) (i.e., heart attack) makes up ~8.5% of CVD and is a common cause of heart failure with a 40% five-year mortality after the first MI. This highlights an urgent need to develop relevant human heart failure models for drug development. This is further evidenced by the disappointing performance of heart failure drugs in clinical trials during the last decade, which has been partially attributed to the distinct differences between human patient hearts and animal heart failure models. Here, we combined major non-genetic causal factors of MI with our previously established cardiac organoids to create the first human organoid model of cardiac infarction. In particular, we leveraged the diffusion limitation in 3D microtissues to recreate the nutrient diffusion gradient across infarcted hearts (i.e., infarct-border-remote zones) in human cardiac organoids to induce cardiac organotypic response to infarction. This enabled the recapitulation of major MI hallmarks in human cardiac organoids at the transcriptomic, structural and functional level.
Project description:The aims of the experiment were to profile the cell types in the adult mouse cardiac interstitium (non-myocyte cells) and how they respond to myocardial infarction injury. Adult, male, Pdgfra +/GFP mice were subject to either a myocardial infarction or sham injury, with cells isolated from cardiac ventricles 3 or 7 days following surgery. We obtained scRNA-seq profiles of two cell fractions: total interstitial (non-myocyte) cell population (TIP) and FACS-sorted GFP+/Cd31- cells (GFP).
Project description:Cardiac hypertrophy can lead to heart failure, and is induced either by physiological stimuli eg postnatal development, chronic exrcise training or pathological stimuli eg pressure or volume overload. This data set looks at microRNA profiles in mouse models to examine whether phosphoinositide 3-kinase (p110 alpha isoform) activity is critical for the maintenance of cardiac function and long term survival in a seeting of heart failure (myocardial infarction). The significance and expected outcome are to recognise genes involved in models of heart failure and attempt to examine underlying regulator pathways involved in possible cardica maintenance in the PI3K mouse model. The matching mRNA gene expression profile (GSE7487) is examined to look for mRNA and microRNA interactions. miRNA expression correlates directly with cardiac function. PI3K regulon ameliorates cardiac stress. Keywords: microRNA profiling, regulatory pathway discovery, genotype comparison Ntg (non-transgenics), dnPI3K (cardiac-specific transgenic model with reduced PI3K activity) and caPI3K (transgenic mice with increased PI3K activity) mice at 3-4 months of age were used. Mice were then subjected to myocardial infarction (occlusion of the left anterior descending aorta) and sham (open heart surgery) for 8 weeks. Left ventricles were harvested. The resulting 6 experimental models were profiled accordingly. The assignment of the mouse models is as follows: caPI3K Sham, Ntg Sham, dnPI3K Sham, caPI3K MI (myocardial infarction), Ntg MI and dnPI3K MI with n = 4 in each group.
Project description:To investigate the transcriotome alteration in myocardial infarction (MI)-associated cells, we performed RNA sequcening analysis with single cells derived from mouse infarcted cardiac tissues or normal left ventricle (LV). Particularly, cardiac endothelial cells (ECs) were traced using a Cdh5-Cre;LSL-tdTomatom system.
Project description:To investigate the transcriotome alteration in endothelial cells (ECs) under a myocardial infarction (MI) condition, we performed RNA sequcening analysis with sorted ECs derived from mouse infarcted cardiac tissues or normal left ventricle (LV).
Project description:Immune cell infiltration in response to myocyte death contributes to extracellular matrix (ECM) remodeling and scar formation after myocardial infarction (MI). Caspase-recruitment domain protein 9 (CARD9) which belongs to CARD family acts as an adapter that mediate the transduction of proinflammatory signaling cascades in innate immunity. To investigate the role of CARD9 in cardiac injury and repair post ischemia, we subjected Card9 knockout mice to myocardial infarction (MI) , and then performed RNA-seq and gene expression profiling analysis using the ischemic cardiac tissues at 3 days post-MI, to identify key genes and pathways regulated by CARD9.
Project description:Coronary heart disease is a main cause of death in the developed world and treatment success remains modest with high mortality rates within one year after myocardial infarction (MI). Thus, new therapeutic targets and effective treatments are necessary. Short telomeres are risk factors for age-associated diseases including heart disease. Here, we address the potential of telomerase (Tert) activation in prevention of heart failure after MI in adult mice. We use adeno-associated viruses for cardiac-specific Tert expression in a mouse model of MI. We find that upon MI, hearts expressing Tert show attenuated cardiac dilation, improved ventricular function and smaller infarct scars concomitant with increased mouse survival by 17% compared to controls. Furthermore, Tert treatment results in elongated telomeres, increased numbers of Ki67 and pH3-positive cardiomyocytes and a gene expression switch towards a regeneration signature of neonatal mice. Our work highlights telomerase activation as a novel therapeutic strategy to prevent heart failure after MI. Mice of one year of age were left untreated (control) or injected with 5*10^11 adeno associated viruses particles of serotype 9 (AAV9) that carry either en empty expression cassette or express telomerase under control of the CMV promoter. Virus injected mice then underwent myocardial infarction induced through permenant left anterior descending artery (LAD) ligation. Mice that survived for six weeks after LAD ligation were sacrificed and 4 hearts per group (AAV9-empty or AAV9-Tert) and 3 control hearts (no virus treatment, no ligation) were subjected to total RNA isolation for micro array analysis.
Project description:The progression of myocardial infarction (MI) involves multiple metabolic disorders. Bile acid metabolites have been increasingly recognized as pleiotropic signalling molecules that regulate multiple cardiovascular functions. G protein-coupled bile acid receptor (TGR5) is one of the receptors sensing bile acids to mediate their biological functions. In this study, we aimed to elucidate the effects of bile acids-TGR5 signaling pathways in myocardial infarction (MI).Mice underwent either the LAD ligation model of MI or sham operation. Both MI and sham mice were gavaged with 10 mg/kg/d DCA or vehicle control since 3-day before the operation. Administration of DCA improved cardiac function at the 3th-day post-MI. The effects of DCA in the heart were determined by RNA-sequencing experiments.