Project description:Pathological processes underlying pressure overload triggered heart failure were mainly analyzed from a cardiomyocyte centric view. To identify new cellular mechanisms, we isolated cardiomyocytes, endothelial cells and fibroblasts as most abundant cardiac cell types from mice in the subacute and chronic stages of pressure overload (by transverse aortic constriction, TAC) and performed RNA-sequencing. We detected highly cell-type specific transcriptional responses with characteristic time courses and active intercellular communication, especially early after TAC. We focused on endothelial cells, and single-cell sequencing in this population showed enhanced expression of collagens and inflammatory mediators at this stage. Importantly, these endothelial transcriptional changes were transduced to the translational level as shown by Ribo-Tag sequencing and verification of collagen protein production by cardiac endothelial cells. In conclusion, we provide a resource of cardiac cellular gene expression in pressure overload and reveal the induction of collagens by endothelial cells as potential therapeutic target.
Project description:Pathological processes underlying pressure overload triggered heart failure were mainly analyzed from a cardiomyocyte centric view. To identify new cellular mechanisms, we isolated cardiomyocytes, endothelial cells and fibroblasts as most abundant cardiac cell types from mice in the subacute and chronic stages of pressure overload (by transverse aortic constriction, TAC) and performed RNA-sequencing. We detected highly cell-type specific transcriptional responses with characteristic time courses and active intercellular communication, especially early after TAC. We focused on endothelial cells, and single-cell sequencing in this population showed enhanced expression of collagens and inflammatory mediators at this stage. Importantly, these endothelial transcriptional changes were transduced to the translational level as shown by Ribo-Tag sequencing and verification of collagen protein production by cardiac endothelial cells. In conclusion, we provide a resource of cardiac cellular gene expression in pressure overload and reveal the induction of collagens by endothelial cells as potential therapeutic target.
Project description:Pathological processes underlying pressure overload triggered heart failure were mainly analyzed from a cardiomyocyte centric view. To identify new cellular mechanisms, we isolated cardiomyocytes, endothelial cells and fibroblasts as most abundant cardiac cell types from mice in the subacute and chronic stages of pressure overload (by transverse aortic constriction, TAC) and performed RNA-sequencing. We detected highly cell-type specific transcriptional responses with characteristic time courses and active intercellular communication, especially early after TAC. We focused on endothelial cells, and single-cell sequencing in this population showed enhanced expression of collagens and inflammatory mediators at this stage. Importantly, these endothelial transcriptional changes were transduced to the translational level as shown by Ribo-Tag sequencing and verification of collagen protein production by cardiac endothelial cells. In conclusion, we provide a resource of cardiac cellular gene expression in pressure overload and reveal the induction of collagens by endothelial cells as potential therapeutic target.
Project description:Aortic banding is an excellent model system to evaluate the process of development of left ventricular hypertrophy in response to hemodynamic stress. The Affymetrix GeneChip MgU74Av1 was used to analyze expression profiles of mice at different time points after surgical intervention for pressure-overload induced hypertrophy. More information about this model may be obtained at http://cardiogenomics.med.harvard.edu/groups/proj1/pages/band_home.html Keywords = Pressure overload, cardiac hypertrophy Keywords: time-course
Project description:Background: BMPER, an orthologue of Drosophila melanogaster crossveinless-2, is a secreted factor that regulates BMP activity in endothelial cell precursors and during early cardiomyocyte differentiation. Although previously described in the heart, the role of Bmper in cardiac development and function remained unknown. Methods: BMPER deficient hearts were phenotyped histologically and functionally using echocardiography and Doppler analysis. Since BMPER -/- mice die perinatally, BMPER +/- mice were then challenged to pressure overload induced cardiac hypertrophy and hind limb ischemia to determine changes in angiogensis and regulation of cardiomyocyte size. Results: We identified for the first time the cardiac phenotype associated with BMPER haploinsufficiency. BMPER mRNA and protein are present in the heart during cardiac development through at least E14.5 but is lost by E18.5. BMPER +/- ventricles are thinner and less compact than sibling wild-type hearts. In the adult, BMPER +/- hearts present with decreased anterior and posterior wall thickness, decreased cardiomyocyte size, and an increase in cardiac vessel density. Despite these changes, BMPER +/- mice respond to pressure overload-induced cardiac hypertrophy challenge largely to the same extent as wild-type mice. Conclusion: BMPER appears to play a role in regulating both vessel density and cardiac development in vivo; however, BMPER haploinsufficiency does not result in marked effects on cardiac function or adaptation to pressure overload hypertrophy. Unpaired, two-condition experiment, wild-type vs BMPER+/- adult hearts. Biological replicates: 4 per condition.