Project description:Dysregulated maternal fatty acid metabolism increases the risk of congenital heart disease (CHD) in offspring with an unknown mechanism, and the effect of folic acid fortification in preventing CHD is controversial. Using gas chromatography coupled to either a flame ionization detector or mass spectrometer (GC-FID/MS) analysis, we find that the palmitic acid (PA) concentration increases significantly in serum samples of pregnant women bearing children with CHD. Feeding pregnant mice with PA increased CHD risk in offspring and cannot be rescued by folic acid supplementation. We further find that PA promotes methionyl-tRNA synthetase (MARS) expression and protein lysine homocysteinylation (K-Hcy) of GATA4 and results in GATA4 inhibition and abnormal heart development. Targeting K-Hcy modification by either genetic ablation of Mars or using N-acetyl-L-cysteine (NAC) decreases CHD onset in high-PA-diet-fed mice. In summary, our work links maternal malnutrition and MARS/K-Hcy with the onset of CHD and provides a potential strategy in preventing CHD by targeting K-Hcy other than folic acid supplementation.
Project description:Mammalian heart development is built on highly conserved molecular mechanisms with polygenetic perturbations resulting in a spectrum of congenital heart diseases (CHD). However, the transcriptional landscape of cardiogenic ontogeny that regulates proper cardiogenesis remains largely based on candidate-gene approaches. Herein, we designed a time-course transcriptome analysis to investigate the genome-wide expression profile of innate murine cardiogenesis ranging from embryonic stem cells to adult cardiac structures. This comprehensive analysis generated temporal and spatial expression profiles, prioritized stage-specific gene functions, and mapped the dynamic transcriptome of cardiogenesis to curated pathways. Reconciling the bioinformatics of the congenital heart disease interactome, we deconstructed disease-centric regulatory networks encoded within this cardiogenic atlas to reveal stage-specific developmental disturbances clustered on epithelial-to-mesenchymal transition (EMT), BMP regulation, NF-AT signaling, TGFb-dependent induction, and Notch signaling. Therefore, this cardiogenic transcriptional landscape defines the time-dependent expression of cardiac ontogeny and prioritizes regulatory networks at the interface between health and disease. To interrogate the temporal and spatial expression profiles across the entire genome during mammalian heart development, we designed a time-course microarray experiment using the mouse model at defined stages of cardiogenesis, starting with embryonic stem cells (ESC, R1 stem cell line), early embryonic developmental stages: E7.5 whole embryos, E8.5 heart tubes, left and right ventricle tissues at E9.5, E12.5, E14.5, E18.5 to 3 days after birth (D3) and adult heart (Figure 1A). At each time point, microarray experiments were performed on triplicate biological samples. Starting at E9.5, tissue samples from left ventricles (LV) and right ventricles (RV) were microdissected for RNA purification and microarray analysis to determine spatially differential gene expression between LV and RV during heart development.
Project description:Lack of the conserved NK2-domain of the cardiac transcription factor Nkx2.5 causes multiple heart defects . The NK2 family of homeobox genes constitutes a family of transcription factors that play an important role in different developmental processes. Members of this group are characterized by two highly conserved protein domains: the homeodomain, conferring DNA binding activity, and the NK2-specific domain (NK2-SD) of yet unknown function. One of the best characterized members of this group is the early cardiogenic marker Nkx2.5. Loss of function of Nkx2.5 leads to embryonic lethality around E10.5 due to an arrest of heart development at the looping stage. We have further dissected the function of Nkx2.5 in vivo by creating a knockout mouse line harboring an in frame deletion of the NK2-SD by Cre/loxP mediated excision. Homozygous mutant mice die at E14.5 due to severe cardiac malformations, e.g. common AV canal, DORV, and VSD. Lack of the NK2-SD leads to downregulation of the ventricular markers MLC-2v and Irx4 specifically in the right ventricle, and is accompanied with reduced right ventricular function. This function of Nkx2.5 seems to be independent of its ability to bind target DNA, since lack of the NK2-SD does not alter the DNA binding activity of Csx/Nkx2.5 in vitro. Heterozygous mutant mice show a spectrum of cardiac defects related to cardiac septation and valve morphogenesis, but lack conduction system defects as reported for heterozygous Nkx2.5 mice. The phenotype observed in NK2-SD mutant mice shows that Nkx2.5 is not only crucial during early steps of cardiogenesis but also plays an important role at later developmental stages. Embryos were isolated at embryonic day 12.5. The entire embryo heart was taken and isolated in ice-cold PBS and immediately frozen on dry-ice. Total RNA was extracted from pooled samples of wildtype, heterozygous and mutant embryos. Keywords = congenital heart disease, Csx, Nkx2.5 Keywords: other
Project description:The genetics, social, cultural and environmental factors pose a great challenge for the diagnosis and treatment of coronary heart disease among different racial groups. We aimed to identify the differentially expressed genes involved in coronary heart disease in Chinese Han people as an aid for screening and diagnosing coronary heart disease. We used microarrays to detail the global programme of gene expression to identify the differentially gene between the patients with coronary heart disease and healthy people in Chinese Han people Three patients with coronary heart disease and three healthy people in Chinese Han people were recruited,total RNA of each samples were extracted from peripheral blood to hybridize with Affymetrix microarrays.
Project description:We report that ablation of one SLN allele positively affects mouse mdx DMD heart failure model mice by several metrics including intracellular calcium handling.
Project description:A major factor in the progression to heart failure in humans is the inability of the adult heart to repair itself after injury. As a result, strategies to induce heart regeneration have received significant interest. We reported that transcription factors Meis1 and Hoxb13 contributes to postnatal cardiomyocyte cell cycle exit, and inhibiting these genes expression promote adult cardiomyocyte regeneration. In order to indentify the downstream targets of these transcription factors we generated ChIP-seq of mouse heart for Meis1 and Hoxb13. The results demonstrate that Meis1 and Hoxb13 act cooperatively to regulate cardiomyocyte maturation and proliferation and provide insights into the link between hyperplastic and hypertrophic growth of cardiomyocytes.