Abstract 4328: Resveratrol inhibits NO-mediated oxidative stress in murine prostate cancer cells

Background: Nitric oxide (NO) is an important signaling molecule in the immune, nervous and cardiovascular systems. NO involves in the regulation of cellular behavior as well as cytotoxic events. Studies demonstrated that resveratrol (RES) (a polyphenolic compound in the skin of red fruits) at high concentration (≥50μM) induces NO production in endothelial F-2 cells and in human umbilical vein endothelial cells. However, the impact of RES on the biological functions of NO are still poorly understood. Therefore, the goal of this study was to investigate the impact of RES on NO-mediated oxidative stress at mitochondria level in mouse prostate cancer (PCa) cells. Experimental Procedures: The transgenic adenocarcinoma of the mouse prostate (TRAMP) cells (mirrors the pathogenesis of human prostate cancer) were cultured in Dulbecco's Modified Eagle Medium (DMEM) supplemented with 10% fetal bovine serum (FBS), penicillin 100 IU/ml, streptomycin 100 μg/ml, 0.005mg/ml bovine insulin, and 10nM Dehydroisoandrosterone in 5% CO2 at 370C. Cells were harvested by trypsinization after 80% confluency (at 4-5 pass), counted (105/ml), and incubated with RES (50uM), RES (50uM) + Deta-NONOate (750uM), Deta-NONOate (750uM), RES (50uM) +L-NMMA (750uM), and L-NMMA (750uM). Deta-NONOate was used as nitric oxide donor while L-NMMA was used as nitric oxide inhibitor. Thereafter, cell viability, NO-estimation in culture supernatant, mitochondrial membrane potential (MMP), total ROS-production in mitochondria and cytoplasm, and apoptotic assay (Annexin-V and caspase-3/7) were carried out. Results and Conclusion: PCa cells incubated with RES showed decreased cell viability, decreased NO production in culture supernatant, decreased MMP, and decreased level of ROS in mitochondria. However, PS-externalization, and total ROS in cytoplasm were found high after normalization with control cells. Further, treatment with Deta-NONOate results in decreased cell viability, decreased total ROS in the cytoplasm, and decreased MMP, while mitochondrial ROS and NO production in culture supernatant were observed highly significant as compared control cells. Furthermore, cells were also exposed to the combination of RES and NO which suggest that RES reduced NO-mediated cell killing and reactive oxygen species generation in TRAMP cells. However, no significant changes were observed after L-NMMA exposure to TRAMP cells. The result demonstrates that RES protect cells from NO-mediated cell killing and induce