Ginsenoside Rg1 ameliorates hypoxia-induced pulmonary arterial hypertension by inhibiting endothelial-to-mesenchymal transition and inflammation by regulating CCN1

Pulmonary arterial hypertension (PAH) is a chronic obstructive disease characterized by vascular remodeling. Studies have confirmed that ginsenoside Rg1 can improve pulmonary hypertension to a certain extent, but the potential mechanism by which it improves hypoxia-induced PAH remains unclear. The aim of this study was to investigate the therapeutic effect of ginsenoside Rg1 on hypoxia-induced PAH. The results showed that hypoxia promoted inflammation, EndMT, and vascular remodeling, which were accompanied by decreased CCN1 levels and increased p-NFκB p65, TGF-β1, and p-Smad 2/3 levels. Treatment with ginsenoside Rg1, recombinant CCN1, BAY-11-7082, and SB-431542 could prevent hypoxia-induced vascular remodeling, reduce the expression of the hypoxia-induced inflammatory cytokines TNF-α and IL-1β, inhibit the expression of the mesenchymal markers α-SMA and Vimentin and restore the expression of the endothelial markers CD31 and VE-cadherin to improve hypoxia-induced EndMT, which may be associated with the upregulation of CCN1 protein expression and downregulation of p-NFκB p65, TGF-β1, and p-Smad 2/3 in rats and cells. siRNA CCN1 transfection increased the expression of p-NFκB p65, TGF-β1, and p-Smad 2/3 and accelerated the occurrence and development of inflammation and EndMT after hypoxia. In summary, our study indicated that hypoxia-induced EndMT and inflammation play a role in hypoxic pulmonary hypertension (HPH). Ginsenoside Rg1 treatment could reverse hypoxia-induced EndMT and inflammation by regulating CCN1 and has potential value in the prevention and treatment of HPH.