Project description:Regulatory Mechanisms of Atrial Remodeling of Mitral Regurgitation Pigs This study enrolled 6 pigs (age: 18 months) and divided into three groups: mitral regurgitation pigs (MR) (n = 2; 2 males sacrificed 12 months after surgery), MR pigs treated with valsartan (MRV) (n = 2; 2 males age-matched to MR sacrificed 12 months after surgery), and normal control pigs (NC) (n = 2; 2 males age-matched to MR pigs). Valsartan (3.43 mg/kg/day), a type I angiotensin II receptor blocker, was administered from one week before surgery and then daily after surgery in the MRV group. We sought to systemically elucidate critical differences in the alteration of RNA expression pattern between the atrial myocardium of pigs with and without MR, and between the atrial myocardium of MR pigs with and without valsartan using high-density oligonucleotide microarrays and functional network enrichment analysis.
Project description:Large White and Meishan pigs were either non-treated or injected with mammalian 1-24 ACTH (Immediate Synachten, Novartis France) at the dose of 250 µg per animal. Pigs were sacrificed either immediately after capture from their home cage (non-treated animals) or 1 hour following ACTH injection. Adrenal glands were immediately collected from pigs and frozen on dry ice and then stored at -80°C until RNA isolation. Keywords: stress response, adrenal, gene expression, pig
Project description:Large White and Meishan pigs were either non-treated or injected with mammalian 1-24 ACTH (Immediate Synachten, Novartis France) at the dose of 250 µg per animal. Pigs were sacrificed either immediately after capture from their home cage (non-treated animals) or 1 hour following ACTH injection. Adrenal glands were immediately collected from pigs and frozen on dry ice and then stored at -80°C until RNA isolation. Keywords: stress response, adrenal, gene expression, pig 47 samples
Project description:Skeletal muscle were collected from pigs treated in the control group, the Lys deficiency group and the Lys rescue group. Then, the samples were analyzed by LC-MSMS.
Project description:Mitral and tricuspid valves are essential for unidirectional blood flow in the heart. They are derived from similar cell sources, and yet congenital dysplasia affecting both valves is clinically rare, suggesting the presence of differential regulatory mechanisms underlying their development. We specifically inactivated Dicer1 in the endocardium during cardiogenesis and found that Dicer1-deletion caused congenital mitral valve stenosis and regurgitation, while it had no impact on other valves. We showed that hyperplastic mitral valves were caused by abnormal condensation and extracellular matrix (ECM) remodeling. Our single-cell RNA Sequencing analysis revealed impaired maturation of mesenchymal cells and abnormal expression of ECM genes in mutant mitral valves. Furthermore, expression of a set of miRNAs that target ECM genes was significantly lower in tricuspid valves compared to mitral valves, consistent with the idea that the miRNAs are differentially required for mitral and tricuspid valve development. We thus reveal miRNA-mediated gene regulation as a novel molecular mechanism that differentially regulates mitral and tricuspid valve development, thereby enhancing our understanding of the non-association of inborn mitral and tricuspid dysplasia observed clinically.
Project description:In atrial fibrillation, disturbed electrical conduction disrupts the coordinated contraction of the heart’s antechambers, increasing the risk of stroke and heart failure. The rising prevalence of this disease approaches 9% in patients >65 years. Studying freshly isolated human atrial tissue and a new mouse model, we here decipher how immune and stromal cells contribute to the structural tissue remodeling that underlies atrial fibrillation. Single-cell transcriptomes from control and diseased human atria documented macrophage doubling at the expense of endothelial and mural cells. An inflammatory monocyte and a pro-fibrotic SPP1+ macrophage cluster expanded in patients with atrial fibrillation. To experimentally perturb pathways observed in patients, we matched their risk factors Hypertension, Obesity and Mitral valvE Regurgitation (HOMER) in mice. Atrial single-cell transcriptomes obtained in HOMER mice, which developed enlarged, fibrillation-prone atria, recapitulated human cell composition and transcriptome variations. Recruitment drove the expansion of atrial macrophages; accordingly, inhibition of monocyte migration reduced arrhythmia in Ccr2-/- HOMER mice. Deleting Spp1 established macrophage-derived osteopontin as a pleiotropic signal that promotes atrial fibrillation through pro-fibrotic, inflammatory crosstalk with an arsenal of local immune and stromal cells. Taken together, we identify SPP1+ macrophages as targets for immunomodulatory therapy in atrial fibrillation.
Project description:In atrial fibrillation, disturbed electrical conduction disrupts the coordinated contraction of the heart’s antechambers, increasing the risk of stroke and heart failure. The rising prevalence of this disease approaches 9% in patients >65 years. Studying freshly isolated human atrial tissue and a new mouse model, we here decipher how immune and stromal cells contribute to the structural tissue remodeling that underlies atrial fibrillation. Single-cell transcriptomes from control and diseased human atria documented macrophage doubling at the expense of endothelial and mural cells. An inflammatory monocyte and a pro-fibrotic SPP1+ macrophage cluster expanded in patients with atrial fibrillation. To experimentally perturb pathways observed in patients, we matched their risk factors Hypertension, Obesity and Mitral valvE Regurgitation (HOMER) in mice. Atrial single-cell transcriptomes obtained in HOMER mice, which developed enlarged, fibrillation-prone atria, recapitulated human cell composition and transcriptome variations. Recruitment drove the expansion of atrial macrophages; accordingly, inhibition of monocyte migration reduced arrhythmia in Ccr2-/- HOMER mice. Deleting Spp1 established macrophage-derived osteopontin as a pleiotropic signal that promotes atrial fibrillation through pro-fibrotic, inflammatory crosstalk with an arsenal of local immune and stromal cells. Taken together, we identify SPP1+ macrophages as targets for immunomodulatory therapy in atrial fibrillation.