Background:Pulmonary artery hypertension (PAH) is an incurable disease with a high mortality rate.Current medications ameliorate symptoms but cannot target adverse vascular remodeling. New therapeutic strategies for PAH need to be established. Methods:Using the weighted gene coexpression network analysis (WGCNA) algorithm, we constructed a coexpression network of dataset GSE117261 from the Gene Expression Omnibus (GEO) database. Key modules were identified by the relationship between module eigengenes and clinical traits. Hub genes were screened out based on gene significance (GS), module membership (MM), and mean pulmonary artery pressure (mPAP). External validations were conducted in GSE48149 and GSE113439. Functional enrichment and immune cell infiltration were analyzed using Metascape and CIBERSORTx. Results:The WGCNA analysis revealed 13 coexpression modules. The pink module had the highest correlation with PAH in terms of module eigengene (r=0.79; P=2e−18) and module significance (MS =0.43).Functional enrichment indicated genes in the pink module contributed to the immune system process and extracellular matrix (ECM). In the pink module, ECM2 (GS =0.65, MM =0.86, ρ=0.407, P=0.0019) and GLT8D2 (GS =0.63, MM =0.85, ρ=0.443, P=0.006) were identified as hub genes. For immune cells infiltration in PAH lung tissue, hub genes were positively correlated with M2 macrophages and resting mast cells, and were negatively correlated with monocytes, neutrophils, and CD4-naïve T cells. Conclusions:Our research identified 2 hub genes ECM2 and GLT8D2 related to PAH. The functions of these hub genes were involved in the immune process and ECM, indicating that they might serve as candidate therapeutic targets for PAH.

Background: Previously, we invented a therapeutic vaccine targeting the endothelin-A receptor (termed ETRQβ-002). ETRQβ-002 successfully prevented the remodeling of pulmonary arterioles (PAs) and right ventricle (RV) without significant immune-mediated damage in experimental pulmonary arterial hypertension (PAH) mice models.Objective: Here, we aim to further evaluate the long-term effects of ETRQβ-002.Methods: PAH mice model was induced by a combination of subcutaneous injection with Sugen5416 and chronic hypoxic conditions (10% O2). PAH mice were immunized with ETRQβ-002 at different time points, and the experiment lasted for 21 weeks. Hemodynamic, histological, and biochemical analyses were conducted to evaluate the long-term effects of ETRQβ-002.Results: We demonstrated that the titer of the specific antibody against ETR-002 could be maintained chronically after periodic booster immunization in PAH mice. Long-term reduction of right ventricular systolic pressure and amelioration of PA remodeling by ETRQβ-002 were confirmed. Moreover, we found that ETRQβ-002 also exerted antiproliferation, anti-inflammation, and antifibrosis effects in PA remodeling. Besides, ETRQβ-002 durably limited pathological RV hypertrophy and fibrosis. Finally, no immune-mediated damage was observed in hepatic or renal function or by pathology in liver and kidney during the long-term administration of ETRQβ-002.Conclusion: Our findings indicate that ETRQβ-002 provides long-term therapeutic effects in Sugen/hypoxia-induced PAH animals and offers a promising clinical prospect for PAH treatment.

The excessive and ectopic pulmonary artery smooth muscle cells (PASMCs) are crucial to the pathogenesis of pulmonary arteriole (PA) remodeling in pulmonary arterial hypertension (PAH). We previously found that microRNA (miR)-30a was significantly increased in acute myocardial infarction (AMI) patients and animals, as well as in cultured cardiomyocytes after hypoxia, suggesting that it might be strongly associated with hypoxia-related diseases. Here, we investigated the role of miR-30a in the PASMC remodeling of PAH. The expression of miR-30a was higher in the serum of PAH patients compared with healthy controls. miR-30a was mainly expressed in PAs and was increased in PASMCs after hypoxia, mediating the downregulation of p53 tumor suppressor protein (P53). Genetic knockout of miR-30a effectively decreased right ventricular (RV) systolic pressure (RVSP), PA, and RV remodeling in the Su5416/hypoxia-induced and monocrotaline (MCT)-induced PAH animals. Additionally, pharmacological inhibition of miR-30a via intratracheal liquid instillation (IT-L) delivery strategy showed high efficiency, which downregulated miR-30a to mitigate disease phenotype in the Su5416/hypoxiainduced PAH animals, and these beneficial effects could be partially reduced by simultaneous P53 inhibition. We demonstrate that inhibition of miR-30a could ameliorate experimental PAH through the miR-30a/P53 signaling pathway, and the IT-L delivery strategy shows good therapeutic outcomes, providing a novel and promising approach for the treatment of PAH.