Project description:Liver metabolism in mice lacking Bmal1 in adipocytes. Comparison between WT and KO revealed no differentially expressed genes at ZT12 and ZT16, and only revealed one gene at ZT8 and ZT20. In contrast many genes were differential at ZT0 and ZT4. With ZT4 having substantially more than ZT0.
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:Early reperfusion of ischemic cardiac tissue remains the most effective intervention for improving clinical outcome following myocardial infarction. However, abrupt increases in intracellular Ca2+ during myocardial reperfusion cause cardiomyocyte death and consequent loss of cardiac function, referred to as ischemia/reperfusion (IR) injury. Cardiac IR is accompanied by dynamic changes in expression of microRNAs (miRNAs), which inhibit specific mRNA targets. miR-214 is up-regulated during ischemic injury and heart failure in mice and humans, but its potential role in these processes is unknown. We show that genetic deletion of miR-214 in mice causes loss of cardiac contractility, increased apoptosis, and excessive fibrosis in response to IR injury. The microarray contains 6 samples, each containing cDNA pooled from 3 mice per group. There are no replicates. The array was designed to make 3 different pairwise comparisons between the following: P14 WT and miR-214 KO hearts; adult WT and miR-214 KO skeletal muscle; adult WT and miR-214 KO hearts
Project description:We generated a tamoxifen-inducible, adipocyte-specific ATGL-KO animals to analyze the role of adipocyte ATGL in cardiac ischemia/reperfusion. KO was induced in 10 weeks old male mice via 7d of consecutive i.p.-injections of 500µg hydroxytamoxifen/day. Pnpla2-flox homozygous, Cre-negative littermates were used as control. After 2 weeks washout phase mice underwent closed chest ischemia with first ligature-induction surgery and 3-7 d later 1 hour closed chest ischemia followed by 24 h reperfusion. Mice were sacrificed and hearts excised to perform spatial transcriptomic analysis on 10X Visium Gene Expression slides. The goal was to identify differences in gene expression between KO and control in the different zones of the heart after ischemia (eg. ischemic, border and remote zone).
Project description:We examined the gene expression profiles of liver samples throughout the day/night cycle (ZT0-ZT4-ZT8-ZT12-ZT16-ZT20) from control mice (night-restricted fed) and mice under short-term caloric restriction.
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.
