Project description:Myocardial infarction (MI) often results in left ventricular (LV) remodeling followed by heart failure (HF). It is of great clinical importance to understand the molecular mechanisms that trigger transition from compensated LV injury to HF and to identify relevant diagnostic biomarkers. In this study, we performed transcriptional profiling of LVs in rats with a wide range of experimentally induced infarct sizes and of peripheral blood mononuclear cells (PBMCs) in animals that developed HF. We used microarrays to investigate gene expression in the left ventricle (LV) accompanying myocardial infarction and concomitant heart failure (HF) in a well validated model of post-infarcted heart failure and to evaluate their reflection in peripheral blood mononuclear cells (PBMCs)
Project description:Myocardial infarction (MI) often results in left ventricular (LV) remodeling followed by heart failure (HF). It is of great clinical importance to understand the molecular mechanisms that trigger transition from compensated LV injury to HF and to identify relevant diagnostic biomarkers. In this study, we performed transcriptional profiling of LVs in rats with a wide range of experimentally induced infarct sizes and of peripheral blood mononuclear cells (PBMCs) in animals that developed HF. We used microarrays to investigate gene expression in the left ventricle (LV) accompanying myocardial infarction and concomitant heart failure (HF) in a well validated model of post-infarcted heart failure and to evaluate their reflection in peripheral blood mononuclear cells (PBMCs) Myocardial infarction (MI) was induced in male Wistar rats by ligation of the proximal left coronary artery. The sham-operated group (control group) was subjected to the same protocol, except that the suture was not tied around the proximal left coronary artery. Sham-operated rats (n=6) and rats with small (n=6), moderate (n=6), and large (n=5) MI size were included into the experiment two months after the operation. Then, left ventricules and blood samples were obtained for RNA extraction and hybridization on Affymetrix microarrays. Microarrays were used to compare the LV and PBMCs transcriptomes of control and experimental animals. The development of heart failure was estimated by echocardiography and catheterization.
Project description:Two matched groups of Heart Failure with reduced ejection fraction patients with no peripheral venous congestion were studied: with recent prior heart failure hospitalization vs. without recent heart failure hospitalization. Peripheral venous congestion was modeled by inflating a cuff around the dominant arm, targeting an ~30mmHg increase in venous pressure (venous stress test). Blood and endothelial cells were sampled before and after 90 minutes of venous stress test.
Project description:Single cell sequencing in peripheral blood mononuclear cells (PBMCs) revealed a novel human-specific long noncoding RNA called heart-failure associated transcript 4 (HEAT4). HEAT4 expression was assessed in several in vitro and ex vivo models of immune cell activation, as well as in the blood of patients with heart failure (HF), acute myocardial infarction (AMI) and cardiogenic shock (CS). The transcriptional regulation of HEAT4 was verified through cytokine treatment and single cell sequencing. Loss-of-function and gain-of-function studies and multiple RNA–protein interaction assays uncovered a mechanistic role of HEAT4 in the monocyte anti-inflammatory gene program. HEAT4 expression and function was characterized in a vascular injury model in NOD.CB-17-Prkdc scid/Rj mice.
