THBS1 mediates hypoxia driven EndMT in pulmonary hypertension

Long-term hypoxia is one of the main causes of pulmonary vascular remodeling in pulmonary hypertension (PH) associated with congenital heart disease (CHD) children. Endothelial to mesenchymal transition (EndMT) is an important pathological basis of pulmonary vascular remodeling in PH. We observed that Fibronectin 1 (FN1) had strong protein-protein interactions with both Thrombospondin 1 (THBS1) and Transglutaminase 2 (TGM2) in PH with venous peripheral bloods samples from pediatric patients and healthy children. LungMAP CellCards and heatmaps of human PAEC in PH patients and lung tissues in hypoxia induced PH mice model were used to show that THBS1 and FN1 were significantly elevated. We studied the relationship between THBS1 and FN1 in vivo, by using SUHX-induced PH mice model, and in vitro, by using hypoxia-induced human PAEC. The results showed that hypoxia could result in EndMT and inhibiting THBS1 could reverse EndMT in vivo and in vitro, verifying our transcriptome results. Taken together, our research demonstrated that THBS1 could mediate hypoxia driven EndMT of PH, providing a new insight of research in the pathophysiology of PH.