Expression data of Sham and post-MI myocardium from swine
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ABSTRACT: The molecular mechanism underlying cardiac remodeling following myocardial infarction have been incompletely understood. Until now, most studies have been performed in rodents. We studied cardiac remodeling in the physiologically more relevant animal model, the swine. Microarray analysis was performed on animals that underwent either sham surgery or permanent ligation of the left coronary artery (MI). RNA was isolated from the remote, non-ischemic, regions of the left ventricle.
Project description:The molecular mechanism underlying cardiac remodeling following myocardial infarction have been incompletely understood. Until now, most studies have been performed in rodents. We studied cardiac remodeling in the physiologically more relevant animal model, the swine. Microarray analysis was performed on animals that underwent either sham surgery or permanent ligation of the left coronary artery (MI). RNA was isolated from the remote, non-ischemic, regions of the left ventricle. RNA was isolated from 8 sham and 8 MI animals three weeks after surgery. Each group contained 4 males and 4 females. Animals used for the study were 2-3 months old Yorkshire x Landrace swine. Only neutered males entered the study.
Project description:Neuregulin-1 (NRG-1) is a paracrine factor critical for cardiac development. We have been examining whether the recombinant NRG-1β isoform known as glial growth factor 2 (GGF2) has therapeutic potential for heart failure. In both small and large animals after experimental myocardial infarction (MI) we have found that GGF2 treatment improves myocardial function and limits progressive myocardial remodeling. To understand potential mechanisms for this effect, we compared gene expression in swine by microarray analysis. We used microarrays to compared th the global gene expression underlying the efficacy of GGF2 treatment for heart injury. Left ventricular tissue remote from the site of infarct was collected from each of 8 animals (3 untreated controls, 3 low dose GGF2-treated and 2 high dose GGF2-treated) and processed for gene expression microarray analysis using Affymetrix porcine genome GeneChips.
Project description:The molecular mechanism underlying cardiac remodeling following exercise have been incompletely understood. Until now, most studies have been performed in rodents. We studied cardiac remodeling in the physiologically more relevant animal model, the swine. Microarray analysis was performed on animals that underwent either and exercise protocol or remained sedentary. RNA was isolated from tissue samples from the endocardial layer of the free wall of the left ventricle.
Project description:The molecular mechanism underlying cardiac remodeling following exercise have been incompletely understood. Until now, most studies have been performed in rodents. We studied cardiac remodeling in the physiologically more relevant animal model, the swine. Microarray analysis was performed on animals that underwent either and exercise protocol or remained sedentary. RNA was isolated from tissue samples from the endocardial layer of the free wall of the left ventricle. RNA was isolated from 8 exercise-trained and 8 sedentary animals 4-5 weeks after start of the protocol. Each group contained 4 males and 4 females. Animals used for the study were 2-3 months old Yorkshire x Landrace swine. Only neutered males entered the study.
Project description:Neuregulin-1 (NRG-1) is a paracrine factor critical for cardiac development. We have been examining whether the recombinant NRG-1β isoform known as glial growth factor 2 (GGF2) has therapeutic potential for heart failure. In both small and large animals after experimental myocardial infarction (MI) we have found that GGF2 treatment improves myocardial function and limits progressive myocardial remodeling. To understand potential mechanisms for this effect, we compared gene expression in swine by microarray analysis. We used microarrays to compared th the global gene expression underlying the efficacy of GGF2 treatment for heart injury.
Project description:Introduction: Cardiac ischemic reperfusion injury (IRI) is paradoxically instigated by re-establishing blood-flow to ischemic myocardium typically from a myocardial infarction (MI). Although revascularization following MI remains the standard of care, effective strategies remain limited to prevent or attenuate IRI. We hypothesized that epicardial placement of human placental amnion/chorion (HPAC) grafts will protect against IRI. Methods: Using a clinically relevant model of IRI, swine were subjected to 45 minutes percutaneous ischemia followed with (MI+HPAC, n=3) or without (MI only, n=3) HPAC. Cardiac function was assessed by echocardiography, and regional punch biopsies were collected 14 days post-operatively. A deep phenotyping approach was implemented by using histological interrogation and incorporating global proteomics and transcriptomics in non-ischemic, ischemic, and border zone biopsies. Results: Our results established HPAC limited the extent of cardiac injury by 50% (11.02.0% vs 22.03.0%, p=0.039) and preserved ejection fraction in HPAC-treated swine (46.8±2.7% vs 35.8±4.5%, p=0.014). We present comprehensive transcriptome and proteome profiles of infarct (IZ), border (BZ), and remote (RZ) zone punch biopsies from swine myocardium during the proliferative cardiac repair phase 14 days post-MI. Both HPAC-treated and untreated tissues showed regional dynamic responses, whereas only HPAC-treated IZ revealed active immune and extracellular matrix remodeling. Decreased endoplasmic reticulum (ER)-dependent protein secretion and increased anti-apoptotic and anti-inflammatory responses were measured in HPAC-treated biopsies. Discussion: We provide quantitative evidence HPAC reduced cardiac injury from MI in a preclinical swine model, establishing a potential new therapeutic strategy for IRI.
Project description:The left anterior descending coronary artery permanent ligation model of myocardial infarction was used to study the time of day differences in genetic responses post-MI between sleep-time MI, wake-time MI, wake-sham and sleep-sham mouse hearts. The micorarray approach allows the investigation of gene expression changes of all genes in sleep-time MI vs. wake-time MI vs. sham hearts.
Project description:microRNAs control cardiac remodeling post myocardial infarction, though the cellular and molecular mechanisms remain unclear. We used microarrays to examine microRNA profiles in mice hearts 21 days after ligation of left anterior descending coronary artery (LAD) versus sham control.
Project description:The purpose of this study was to unravel the differences in the molecular profile between ischemic and remote myocardium after AMI.
Project description:This study was a part of a larger study assessing the response of young pigs to cardiac ischemia/reperfusion (IR) injury. A mild cardiac injury approach (IR) was used in post-weaned pigs (1-month), to assess regenerative repair in young large mammals after transient ischemic injury. Female and male postnatal day (P)30 pigs were subjected to cardiac ischemia (1-hour) by occlusion of the left anterior descending artery followed by reperfusion (IR), or to sham operation. In pigs subjected to IR, myocardial damage occurred, indicated by increased circulating cardiac troponin I 2-hours post-ischemia. In addition, cardiac ejection fraction (EF) was significantly decreased 2-hours post-ischemia and reduced EF was maintained to the 4-week study end-point. Histology demonstrated evidence of CM cell cycling at 2-months of age in multinucleated CMs in both sham-operated and IR pigs. Following IR, regional scar formation and inflammation in the epicardial region proximal to injury were observed 4-weeks post-IR. Sex differences in cardiac function and collagen deposition were found, highlighting the importance of representing both sexes in cardiac injury studies. Together, our results describe an effective novel cardiac injury model in 1-month old swine, at a time when CM are still cycling. However, pigs subjected to IR show a prolonged decrease in cardiac function, and the formation of a small, regional scar with increased inflammation. Together, these data demonstrate that 1-month old pigs do not regenerate myocardium, but form a scar, after transient IR injury.