Project description:Heart failure is among the leading causes of death globally. Ventricular failure progresses through a hypertrophic compensatory phase followed by failure of the ventricle function through rapid decompensation. In order to unravel right heart specific mechanisms of disease, rat animal models were established that (i) reflect the slowly progressive mode of compensation / decompensation and (ii) allow comparative analyses of left versus right heart failure in the same experimental set up. Non-restrictive clips around the pulmonary artery (pulmonary artery banding, PAB) or the aorta (aortic banding, AOB) were surgically implanted into weanling rats. Upon animal growth the clips become increasingly constrictive, leading to a compensatory, hypertrophic state at around 6 weeks and heart failure at 21 (PAB) or 24 weeks (AOB). Disease progression was monitored functionally and by sonography. Differential gene expression analysis was performed for all three treatment groups (sham, AOB, PAB), at both time points (compensation, decompensation) and for both ventricles.
Project description:The molecular mechanisms of progressive right heart failure are incompletely understood. We systematically examined transcriptomic changes occurring over months in isolated cardiomyocytes or whole heart tissues from failing right and left ventricles in rat models of pulmonary artery (PAB) or aortic banding (AOB). Detailed bioinformatics analyses resulted in the identification of gene signatures, protein, and transcription factor networks specific to ventricles and compensated or decompensated disease states. Proteomic and RNA-FISH analyses confirmed PAB-mediated regulation of key genes (including proenkephalin) and revealed spatially heterogeneous mRNA expression in the heart. Intersection of rat PAB-specific gene sets with transcriptome data sets from human patients with chronic thromboembolic pulmonary hypertension led to the identification of more than 50 genes whose expression levels correlated with the severity of right heart disease, including multiple matrix-regulating and secreted factors. These data define a conserved, differentially regulated genetic network associated with right heart failure in rats and humans
Project description:Right ventricular failure (RVF) due to pressure load is a major cause of death in congenital heart diseases and pulmonary hypertension. The mechanisms of RVF are yet unknown. Research is hampered by the lack of a good RVF model. Our aim was to study the pathophysiology of RVF in a rat model of chronic pressure load. Wistar rats (n=19) were subjected to pulmonary artery banding (PAB, 1.1mm) or sham surgery (CON). All PAB rats developed RVF (reduced cardiac output, RV stroke volume, TAPSE, increased end diastolic pressure, all p<0.05 vs. CON) but clinical symptoms of RVF (inactivity, ruffled fur, dyspnea, ascites) necessitating termination ensued in a subset (5/12) of rats (RVF+) after a period of 52±5 days. Rats with RVF+ had significantly worse RV function and pericardial effusion and liver congestion compared to RVF rats without symptoms (all p<0.05), despite similar pressure load (p=NS RVF vs. RVF+). Chronic pulmonary artery banding invariably leads to RV failure in rats, and a subset transitions to advanced clinical RVF. RVF is characterized by enhanced contractility, progressive diastolic dysfunction and derangement of energy metabolism, thus improving diastolic function and targeting RV metabolism may be the keys to treating RVF. Total RNA optainded ( Heart) of 7 Controls ,5 RVF+ and 4 RVF samples where used for this array study
Project description:Right ventricular failure (RVF) due to pressure load is a major cause of death in congenital heart diseases and pulmonary hypertension. The mechanisms of RVF are yet unknown. Research is hampered by the lack of a good RVF model. Our aim was to study the pathophysiology of RVF in a rat model of chronic pressure load. Wistar rats (n=19) were subjected to pulmonary artery banding (PAB, 1.1mm) or sham surgery (CON). All PAB rats developed RVF (reduced cardiac output, RV stroke volume, TAPSE, increased end diastolic pressure, all p<0.05 vs. CON) but clinical symptoms of RVF (inactivity, ruffled fur, dyspnea, ascites) necessitating termination ensued in a subset (5/12) of rats (RVF+) after a period of 52±5 days. Rats with RVF+ had significantly worse RV function and pericardial effusion and liver congestion compared to RVF rats without symptoms (all p<0.05), despite similar pressure load (p=NS RVF vs. RVF+). Chronic pulmonary artery banding invariably leads to RV failure in rats, and a subset transitions to advanced clinical RVF. RVF is characterized by enhanced contractility, progressive diastolic dysfunction and derangement of energy metabolism, thus improving diastolic function and targeting RV metabolism may be the keys to treating RVF.
Project description:We reported the RNAseq analyses of lungs tissues in neonatal SD rats with or without reduced pulmonary blood flow. Lung hypoperfution was induced by causing the supravalvular pulmonary stenosis through performing pulmonary artery banding surgery within 24 hours postnatally (P1). RNAseq analyses of the upper lobe of the right lung tissues was generated at P7 from 5 sham-operated rats and 4 pulmonary artery banding rats (1 rat dead before sample collection). The results revealed that there were 2666 differentially expressed genes between PAB and sham group at P7, among which 1255 were upregulated and 1411 were downregulated.
Project description:Right ventricular failure was induced thourgh pulmonary banding in 11 pigs. Right ventricular failure was defined as a SRVP >50 mmHg during two hours. After right ventricular failure was induced, half the pigs were treatmed with a Glenn-shunt combined with pulmonary banding for one hour, and the other half served as control group with pulmonary banding only. The aim was to study the change in global gene expression during right ventricular failure due to pulmonary banding, and the effect of volume unloading during pulmonary banding. 11 pigs. Samples at the following time periods: 1) Baseline 2) Right ventricular failure 3) Treatment with modified Glenn-shunt/Control. After Right ventricular failure, pigs were divided into two groups a) Treatment with modified Glenn-shunt or b) Control group
Project description:We demonstrated that, four weeks after the pulmonary artery banding (PAB) operation, rats could be divided into two groups: an F+ group in which the fibrotic area occupied more than 6.5% of the whole area of the heart tissues, and an F- group in which the fibrotic area occupied less than 6.5% of this area. We used microarrays to elucidate the fibrosis initiating master factor using heart samples obtained from PAB or sham-operated rats.
Project description:Right ventricular failure was induced thourgh pulmonary banding in 11 pigs. Right ventricular failure was defined as a SRVP >50 mmHg during two hours. After right ventricular failure was induced, half the pigs were treated with a Glenn-shunt combined with pulmonary banding for one hour, and the other half served as control group with pulmonary banding only. The aim was to study the change in global gene expression during right ventricular failure due to pulmonary banding, and the effect of volume unloading during pulmonary banding.
Project description:To investigate the effect of pressure overload (PO) during postnatal right ventricular (RV) development, we established the RV PO model by conducting pulmonary artery banding (PAB) surgery on neonatal Sprague-Dawley (SD) rats. We then performed gene expression and chromatin openness profiling analysis using data obtained from RNA-seq and ATAC-seq of RV free walls from PO and sham-operated rats at postnatal day 21 (P21).
Project description:We reported the RNAseq analyses of lungs tissues in neonatal SD rats with or without reduced pulmonary blood flow(RPF). RPF was induced by causing the supravalvular pulmonary stenosis through pulmonary artery banding within 24 hours postnatally (P1). RNAseq analyses of the upper lobe of the right lung tissues was generated at P14 from 5 sham-operated rats and 5 PAB rats. The results revealed that there were 2013 differentially expressed genes between PAB and sham group at P7, among which 936 were upregulated and 1077 were downregulated. GO and KEGG pathway analysis of downregulation of DEGs indicated that abundantly enriched terms of cell migration and metabolism.