Matrine alleviates hypoxia‐induced inflammation and pulmonary vascular remodelling via RPS5/NF‐κB signalling pathway

Abstract Hypoxia‐induced vasoconstriction and vascular remodelling are the main pathological features of hypoxic pulmonary arterial hypertension (HPAH), and inflammation is participated in the occurrence of pulmonary vascular remodelling (PVR). Matrine is an alkaloid with the effects of anti‐inflammation, antifibrosis and antitumour. But, few studies have explored the role of matrine in regulating PVR, and the related mechanisms are still unknown. In this study, we found that hypoxia‐induced pulmonary artery smooth muscle cells (PASMCs) proliferation and inhibited its apoptosis, reduced the expression of ribosomal protein s5 and activated the nuclear factor kappa‐B (NF‐κB) signalling. Matrine, sildenafil and NF‐κB inhibitor Bay 11‐7082 could reverse these changes and impel the cell cycle in phase S retardation, and reduced the expression of p50, p65, proliferating cell nuclear antigen (PCNA), Bcl‐2. In addition, matrine could lower right ventricular systolic pressure and mean pulmonary artery pressure of rats, α‐smooth muscle actin and PCNA expression in pulmonary artery media, the levels of tumor necrosis factor‐α and interleuki‐1β, thus improved hypoxia‐induced PVR. This study indicated that matrine could alleviate inflammation and improve PVR through reversing the imbalance of proliferation and apoptosis of PASMCs, thus it had a therapeutic effect on HPAH.