Identification of LDHA as a Potential Therapeutic Target for Pulmonary Hypertension Through Modulation of Endothelial-To-Mesenchymal Transition.

Endothelial-to-mesenchymal transition (EndMT) induced by dysfunctional pulmonary artery endothelial cells (PAECs) is regarded as an initiating and pivotal factor in pulmonary hypertension (PH). This study focuses on identifying a novel therapeutic target for regulating EndMT in PH. A comprehensive analysis of 2 hypoxic PAECs datasets yielded 310 overlapping upregulated and 229 downregulated differentially expressed genes (DEGs). These upregulated DEGs were primarily enriched in HIF-1 signalling pathway and glycolysis/gluconeogenesis, while downregulated only in spliceosome, as indicated by KEGG. Through PPI network analysis and the application of MCC algorithms, 5 hub genes were identified among these upregulated DEGs: GAPDH, LDHA, ALDOA, PFKL, and PFKP. Their enrichment in the 2 aforementioned pathways was confirmed by cross-pathway DEGs analysis and ClueGo. Among the hub genes, LDHA was chosen as the key gene based upon expression and correlation analysis of the validation set from PH patients. Subsequent GSEA also revealed the enrichment of LDHA in these 2 pathways. Additionally, the increased expression of LDHA protein in tissues and cells was confirmed, and the elevated enzymatic activity of LDHA in clinical serum samples was also verified. From 2 online databases, 4 LDHA inhibitors were filtered out, and the stable binding between the inhibitors and the LDHA protein was confirmed through molecular docking and molecular dynamics simulation. Finally, the experimental results indicated that one of the inhibitors FX11 reversed EndMT by inhibiting the lactate-SNAI1 axis, thereby alleviating hypoxia-induced PH. The potential of LDHA as a therapeutic target for PH by modulating EndMT was proposed in this study.