Inhibition Of Rosmarinic Acid On The Apoptosis Of Vascular Smooth Muscle Cells Induced By Hydrogen Peroxide

Background:The apoptosis of vascular smooth muscle cells (VSMCs) is closely associated with the formation, development and disruption of As and plays an important role in the formation , disruption of plaque, vascular remodeling and thrombogenesis. Therefore, regulation on VSMCs apoptosis will become a new pathway to stabilize As plaque and cure As. Rosmarinic acid (RosA) is a natural and hydroxylated phenols compound frequently found in plants Lamiaceae and Perilla frutescens, has exhibited strong antioxidative, anti-inflammatory and anti-Ca²⁺ activities. Previously, we had demonstrated that RosA could inhibit hydrogen peroxide (H₂O₂) -induced ECV304 cells apoptosis by up-regulating Bcl-2 protein and down-regulating Bax protein.However,the effect of Ros A on H₂O₂-induced VSMCs oxidative stress injury and apoptosis is less clear.In this research,we aim to investigate the effects of Ros A on H₂O₂ - induced apoptosis in rat VSMCs and its related mechanisms,and try to provide theory evidence for developing Ros A as a new drug for As .Methods:Firstly, H₂O₂ of different concentrations were added to the medium of VSMCs cultured in vitro for 24 hours, percentage of apoptosis was measured by flow cytometry, morphologic change was measured by nuclear staining with AO ,in order to determined the optimal H₂O₂ concentration to induce VSMCs apoptosis. Then groups was divided on experiment as follows: (1) normal control group, (2) H₂O₂ damage group (3) Ros A (10,20,40 μmol/L concentrations) + H2O2 groups (4) Positive drug Vitamin E (50 μmol/L concentrations) + H₂O₂ group. Cultured VSMCs were pretreated with different concentrations of Ros A or vitamin E for 30 minutes before being treated with the optimal H₂O₂ for 24 hours. Cell viability was measured...