Abstract
BACKGROUND: Vascular endothelial dysfunction (VED) is one of the main pathogenic events in pulmonary arterial hypertension (PAH). Previous studies have demonstrated that the ginsenoside Rg1 (Rg1) can ameliorate PAH, but the mechanism by which Rg1 affects pulmonary VED in hypoxia-induced PAH remains unclear. METHODS: Network pharmacology, molecular docking and other experiments were used to explore the mechanisms by which Rg1 affects PAH. A PAH mouse model was established via hypoxia combined with the vascular endothelial growth factor (VEGFR) inhibitor su5416 (SuHx), and a cell model was established via hypoxia. The functions of Rg1 in VED, oxidative stress, inflammation, mitophagy, and TXNIP and NLRP3 expression were examined. RESULTS: In hypoxia-induced VED, progressive exacerbation of oxidative stress, inflammation, and mitophagy were observed, and were associated with elevated TXNIP and NLRP3 expression in vivo and in vitro. Rg1 improved hypoxia-induced impaired endothelium-dependent vasodilation and increased nitric oxide (NO) and endothelial NO synthase (eNOS) expression. Rg1, SRI37330 (a TXNIP inhibitor), MCC950 (an NLRP3 inhibitor), and Liensinine (a mitophagy inhibitor) attenuated oxidative stress, inflammation, and mitophagy by reducing the expression of TXNIP and NLRP3 in mice and cells. Furthermore, the combination of SB203580 (a mitophagy agonist) with Rg1 disrupted the protective effect of Rg1 on hypoxia-induced pulmonary artery and human pulmonary artery endothelial cells (HPAECs). CONCLUSION: Rg1 improves hypoxia-induced pulmonary vascular endothelial dysfunction through TXNIP/NLRP3 pathway-modulated oxidative stress, inflammation and mitophagy.