Protective effects of fruit extract of Rosa canina and quercetin on human umbilical vein endothelial cell injury induced by hydrogen peroxide

The Nastaran plant, with the scientific name of Rosa canina, has been used since ancient times as a plant with medicinal properties. In the present study, human umbilical vein endothelial cells (HUVECs) were used to examine the protective effects of R. canina fruit extract (RCFE) and its flavonoid ingredient (quercetin) against H2O2-induced cell injury. RCFE (1.25-20 mu g/mL) and quercetin (1.25-20 mu M) were exposed to H2O2-oxidizing agent (1 and 2 mM) and the protective effect was examined on HUVEC cells by Alamar Blue test. The amount of intracellular reactive oxygen species (ROS) was measured by using DCFDA reagent by fluorimetric method. The effects of RCFE and quercetin on cell apoptosis were studied by staining with hypotonic PI solution and flow cytometry. The amount of PARP and survivin involved in the apoptotic process was measured using the western blot analysis. The results of the Alamar Blue test showed that RCFE and quercetin could reduce the toxicity of H2O2. RCFE and quercetin were able to significantly increase cell viability against H2O2. Also, it was found that RCFE and quercetin reduced the production of ROS by H2O2. It was found that RCFE and quercetin reduced the apoptosis and sub-G1 peak area in flow histogram after exposure of cells to H2O2. Based on western blot results, pretreatment with RCFE and quercetin could significantly increase survivin protein after exposure of cells to H2O2. Also, RCFE and quercetin could significantly reduce the amount of cleaved PARP after exposure of cells to H2O2. RCFE and its ingredient (quercetin) can be considered a promising source of phytochemicals in the prevention of cardiovascular diseases.