Project description:Myocardial regeneration capacity declines during the first week after birth and is linked to the adaptation to oxidative metabolism. Utilizing this regenerative window, we characterized the transcriptomic changes in myocardial injury in 1-day-old regeneration-competent and 7-day-old regeneration-compromised mice. The mice were either sham-operated or received left anterior descending coronary artery ligation to induce myocardial infarction and acute ischemic heart failure. Myocardial tissue samples were collected after 3- and 21-day follow-up period. Whole transcriptome and miRNA NGS data was analyzed. We identified specific time-dependent transcription factors and networks contributing to both regeneration competence and failure.
Project description:Myocardial regeneration capacity declines during the first week after birth and is linked to the adaptation to oxidative metabolism. Utilizing this regenerative window, we characterized the transcriptomic changes in myocardial injury in 1-day-old regeneration-competent and 7-day-old regeneration-compromised mice. The mice were either sham-operated or received left anterior descending coronary artery ligation to induce myocardial infarction and acute ischemic heart failure. Myocardial tissue samples were collected after 3- and 21-day follow-up period. Whole transcriptome and miRNA NGS data was analyzed. We identified specific time-dependent transcription factors and networks contributing to both regeneration competence and failure.
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:Sexual dimorphisms are well recognized in various cardiac diseases, including myocardial infarction (MI). MI develops later in women, but once established, it contributes more persistent symptoms and higher mortality than in men. Although mRNA-level sexual dimorphism of MI have been reported, whether miRNA transcriptome also confers such dimorphism remains unknown. Comprehensive understanding of the mRNA- and miRNA-level genetic programs underlying the heart sexual dimorphisms will expectedly improve clinical outcome by facilitating the development of gender specific treatment strategies. Here, by conducting miRNA microarray analysis of human MI samples, we set out to characterize the heart sexual dimorphisms at the level of miRNA transcriptome Human tissue samples, acquired during post-mortem examination and frozen in liquid nitrogen, were provided by the department of pathology, Tokyo Metropolitan Geriatric Hospital after the approval from the ethical committee. Age- and sex-matched cohorts were selected to compare healthy hearts to those with post-MI LV remodeling. Border zone for myocardial infarction was sampled. Total RNA was extracted using Sepasol solution (Sepasol-RNA I super G, nakalai tesque, Japan), and microarray analysis was performed using Affymetrix GeneChip® miRNA 3.0 Arrays
Project description:Affymetrix microarray analysis of molecular changes after myocardial infarction. Samples of heart tissue were analyzed after myocardial infarction from WT and reg3beta knock-out mice. Samples from scar tissue and samples adjacent to the scar were analyzed. In the experiment we primarily compared infarction zone of wild-type to infarction zone of knock-out animals, and remote zone of wild-type to remote zone of knock-outs.
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:Mice with homozygous null mutations in the HDL receptor (SR-BI) and apoE genes (SR-BI KO/apoE double KO (dKO) mice) spontaneously develop occlusive, atherosclerotic coronary artery disease (CAD) and die prematurely (50% mortality at 42 days of age) on standard chow diet feeding. Microarray analysis was performed to investigate the changes in gene expression profiles during the development of spontaneous severe CAD, which includes myocardial infarction and heart failure. These data will provide new insights in understanding the pathophysiology of CAD. The whole Hearts from dKO or SR-BI+/- apoE-/- (HET) mice (n=9-12) were harvested at 21, 31 and 43 days of age, and analyzed using Affymetrix microarrays. dKO mice do not show detectable signs of CAD at 21 days of age, small myocardial infarction (MI) and heart failure at 31 days of age, and extensive MI and severe heart failure at 43 days of age (50% mortality at 42 days of age). Each mouse was assigned to one array. SR-BI+/- apoE-/- mice (HET) which do not develop detectable signs of CAD on chow diet were used as controls.The data also include those from probucol treated dKO and HET mice (n=2-8).