Project description:Despite recent improvements in management of idiopathic pulmonary arterial hypertension, mortality remains high. Understanding the alterations in the transcriptome–phenotype of the key lung cells involved could provide insight into the drivers of pathogenesis. In this study, we examined differential gene expression of cell types implicated in idiopathic pulmonary arterial hypertension from lung explants of patients with idiopathic pulmonary arterial hypertension compared to control lungs. After tissue digestion, we analyzed all cells from three idiopathic pulmonary arterial hypertension and six control lungs using droplet-based single cell RNA-sequencing. After dimensional reduction by t-stochastic neighbor embedding, we compared the transcriptomes of endothelial cells, pericyte/smooth muscle cells, fibroblasts, and macrophage clusters, examining differential gene expression and pathways implicated by analysis of Gene Ontology Enrichment. We found that endothelial cells and pericyte/smooth muscle cells had the most differentially expressed gene profile compared to other cell types. Top differentially upregulated genes in endothelial cells included novel genes: ROBO4, APCDD1, NDST1, MMRN2, NOTCH4, and DOCK6, as well as previously reported genes: ENG, ORAI2, TFDP1, KDR, AMOTL2, PDGFB, FGFR1, EDN1, and NOTCH1. Several transcription factors were also found to be upregulated in idiopathic pulmonary arterial hypertension endothelial cells including SOX18, STRA13, LYL1, and ELK, which have known roles in regulating endothelial cell phenotype. In particular, SOX18 was implicated through bioinformatics analyses in regulating the idiopathic pulmonary arterial hypertension endothelial cell transcriptome. Furthermore, idiopathic pulmonary arterial hypertension endothelial cells upregulated expression of FAM60A and HDAC7, potentially affecting epigenetic changes in idiopathic pulmonary arterial hypertension endothelial cells. Pericyte/smooth muscle cells expressed genes implicated in regulation of cellular apoptosis and extracellular matrix organization, and several ligands for genes showing increased expression in endothelial cells. In conclusion, our study represents the first detailed look at the transcriptomic landscape across idiopathic pulmonary arterial hypertension lung cells and provides robust insight into alterations that occur in vivo in idiopathic pulmonary arterial hypertension lungs.
Project description:There is marked sexual dimorphism displayed in the onset and progression of pulmonary hypertension (PH). Females more commonly develop pulmonary arterial hypertension (PAH), however, females with PAH and other types of PH have better survival than males. Pulmonary microvascular endothelial cells play a crucial role in the pulmonary vascular remodelling and increased pulmonary vascular resistance of PH. Given this background, we hypothesized that there are sex differences in the pulmonary microvascular endothelium basally and in response to hypoxia that are independent of the sex hormone environment.
Project description:Endothelial cell dysfunction plays a critical role in the development and pathogenesis of pulmonary arterial hypertension (PAH). We aimed to characterize the endothelial cell transcriptomic changes in PAH. We carried out bulk RNA sequencing of lung endothelial cells isolated from an endothelial cell lineage tracing mouse model in control and SU5416/Hypoxia-induced PAH conditions.
Project description:Endothelial cells (EC) sense stimuli in the circulation and release responsive signaling molecules to coordinate the multicellular adaptations required to maintain vascular homeostasis. The goal of this study were to analyze the transcriptional changes induced by hypoxia in control donor pulmonary arterial endothelial cells and the effect of loss of BMPR2 that is associated with pulmonary arterial hypertension.
Project description:Early postnatal life is considered as a critical time window for determination of long-term metabolic states and organ functions. Extrauterine growth restriction (EUGR) causes the development of adult onset chronic diseases, including pulmonary arterial hypertension (PAH). However, the effects of nutritional disadvantages during early postnatal period on pulmonary vascular consequences in later life are not fully understood. Our study was designed to test whether epigentic dysregulation mediates the cellular memory of this early postnatal event. To test this hypothesis, we isolated pulmonary vascular endothelial cells (PVEC) by magnetic-activated cell sorting (MACS) from EUGR and control rats. A postnatal insult, nutritional restriction-induced EUGR caused development of an increased pulmonary artery pressure at 9-week of age in male rats. MeDIP-chip (Methyl-DNA immune precipitation chip), genome-scale mapping studies to search for differentially methylated loci between control and EUGR rats revealed significant difference in cytosine methylation between EUGR and control rats. We validated candidate dysregulated loci with quantitative assays of cytosine methylation and gene expressions. EUGR changes cytosine methylation at ~500 loci in male rats at 9 weeks of age, preceding the development of PAH and these represent candidate loci for mediating the pathogenesis of pulmonary vascular disease that occurs later in life. These results demonstrate that epigenetic dysregulation is a strong mechanism for propagating the cellular memory of early postnatal events, causing changes in expression of genes and long term susceptibility to PAH, and further providing a new insight into prevention and treatment of EUGR-related PAH. MeDIP together with microarray analysis demonstrated that significant differences in cytosine methylation between EUGR and control rats. Comparison of EUGR(n=3) vs Control (n=3) male rats' pulmonary vascular endothelial cells in 9-week age old rats
Project description:Expression analysis of genes potentially regulated by BMPRII and beta-catenin. BMPRII has been linked as a genetic factor to the disease pulmonary arterial hypertension. Comparison of total mRNA obtained from human pulmonary artery endothelial cells treated with control, bone morphogentic protein receptor II, or beta-catenin siRNA