Paeoniflorin suppresses the apoptosis and inflammation of human coronary artery endothelial cells induced by oxidized low-density lipoprotein by regulating the Wnt/β-catenin pathway

CONTEXT: Paeoniflorin (PF) contributes to improving coronary artery disease (CAD). OBJECTIVE: This study clarified the efficiency of PF in CAD and the molecular mechanism. MATERIALS AND METHODS: Human coronary artery endothelial cells (HCAECs) were treated with oxidized low-density lipoprotein (ox-LDL; 20, 40, 80 and 160 μg/mL) and PF (0.05, 0.1 0.2 and 0.4 mM). To study cell phenotypes, HCAECs were treated with 80 μg/mL ox-LDL with or without 0.1 mM PF for 24 h, and cell viability and apoptosis were evaluated using the methyl thiazolyl tetrazolium (MTT) assay and flow cytometry, respectively. In addition, inflammatory cytokines levels were measured by enzyme-linked immunosorbent assay (ELISA). Western blot evaluated the Wnt/β-catenin pathway-related factors. RESULTS: ox-LDL and PF (0.2 and 0.4 mM) suppressed cell viability in a dose-dependent manner. The IC(50) value of PF was 722.9 nM. PF facilitated cell viability (115.76%), inhibited apoptosis (46.28%), reduced IL-6 (63.43%) and IL-8 (66.70%) levels and increased IL-10 levels (181.15%) of ox-LDL-treated HCAECs. Additionally, PF inactivated the Wnt/β-catenin pathway, and XAV939 treatment further promoted cell viability (120.54%), suppressed apoptosis (56.92%), reduced the levels of IL-6 (76.16%) and IL-8 (86.82%) and increased the IL-10 levels (120.22%) of ox-LDL-induced HCAECs after PF treatment. Moreover, PF alleviated plaque lesions of the aorta and aorta root and serum lipid of ApoE(−/−) mice with a high-fat diet. DISCUSSION AND CONCLUSIONS: This study first revealed that PF inhibited ox-LDL-induced HCAECs apoptosis and inflammation via the Wnt/β-catenin pathway and alleviated CAD, suggesting the potential of PF as a drug for CAD treatment.