Project description:Nuclear receptor Reverb alpha is a component of circadian rythm which could be evolved in cardioprotection strategy. We test if pharmacological modulation of these target could be suitable for cardioprotection after ischemia reperfusion injury We used microarrays to detail the global programme of gene expression
Project description:Nuclear receptor Reverb alpha is a component of circadian rythm which could be evolved in cardioprotection strategy. We test if pharmacological modulation of these target could be suitable for cardioprotection after ischemia reperfusion injury We used microarrays to detail the global programme of gene expression
Project description:Heart disease remains the leading cause of death globally. Although reperfusion following myocardial ischemia can prevent death by restoring nutrient flow, ischemia/reperfusion injury can cause significant heart damage. The mechanisms that drive ischemia/reperfusion injury are not well understood; currently, few methods can predict the state of the cardiac muscle cell and its metabolic conditions during ischemia. Here, we explored the energetic sustainability of cardiomyocytes, using a model for cellular metabolism to predict the levels of ATP following hypoxia. We modeled glycolytic metabolism with a system of coupled ordinary differential equations describing the individual metabolic reactions within the cardiomyocyte over time. Reduced oxygen levels and ATP consumption rates were simulated to characterize metabolite responses to ischemia. By tracking biochemical species within the cell, our model enables prediction of the cell’s condition up to the moment of reperfusion. The simulations revealed a distinct transition between energetically sustainable and unsustainable ATP concentrations for various energetic demands. Our model illustrates how even low oxygen concentrations allow the cell to perform essential functions. We found that the oxygen level required for a sustainable level of ATP increases roughly linearly with the ATP consumption rate. An extracellular O2 concentration of ~0.007 mM could supply basic energy needs in non-beating cardiomyocytes, suggesting that increased collateral circulation may provide an important source of oxygen to sustain the cardiomyocyte during extended ischemia. Our model provides a time-dependent framework for studying various intervention strategies to change the outcome of reperfusion.
Project description:The heart of late pregnant (LP) rodents is more prone to ischemia/reperfusion (I/R) injury compared to non-pregnant rodents. We hypothesized that Intralipid (ITLD) protects the heart in LP rodents against I/R injury. We performed genome-wide expression profiling to identify the underlying mechanisms. Female LP rat hearts were subjected to ischemia followed by reperfusion with vehicle or ITLD (one bolus of 5mg/kg).
Project description:Rats underwent surgery for LAD ligation for 30 min followed by reperfusion. Heart ventricles were collected 2d or 7d after reperfusion. Keywords: rat heart ventricles, LAD - left anterior descending coronary artery, IR - ischemia-reperfusion
Project description:Rev-erbα/β are druggable components of the molecular circadian clock. Rev-erb agonists can mitigate pressure overload-induced cardiac hypertrophy and myocardial infarction in mice, while Rev-erb antagonist increases myocardial ischemia-reperfusion tolerance ex vivo at the sleep-to-wake transitionHow cardiac Rev-erb regulates heart function has not been studied in vivo. ChIP-seq of Rev-erbα in the heart confirmed the robust diurnal rhythmicity of Rev-erbα genome binding with about 5 times more binding at ZT9 than at ZT21.
Project description:Ischemic preconditioning is effective in limiting subsequent ischemic acute kidney injury in experimental models. microRNAs are an important class of post-transcriptional regulator and show promise as biomarkers of kidney injury. An evaluation was performed of the time- and dose-dependent effects of ischemic preconditioning in a rat model of functional (bilateral) ischemia-reperfusion injury. A short, repetitive sequence of ischemic preconditioning resulted in optimal protection from subsequent ischemia-reperfusion injury. A detailed characterization of microRNA expression in ischemic preconditioning/ischemia-reperfusion injury was performed by small RNA-Seq.
