Resveratrol is a plant-derived polyphenol that has been widely studied for its putative health promoting effects. Many of those studies have been conducted in cell culture, in supra-physiological levels of oxygen and glucose. Resveratrol interacts with reactive oxygen species (ROS) as an antioxidant or pro-oxidant. Resveratrol affects the expression and activities of ROS-producing enzymes and organelles. It is therefore important to consider how cell culture conditions might determine the effects of resveratrol on cultured cells. We determined the effects of resveratrol on cell growth, hydrogen peroxide production, and mitochondrial network characteristics in C2C12 mouse myoblasts and PC3 human prostate cancer cells under conditions of physiological (5%) and supra-physiological (18%) oxygen, and normo- (5 mM) and hyper-glycemia (25 mM). Interestingly, most effects of resveratrol on the parameters measured here were dependent upon prevailing oxygen and glucose levels during the experiment. Many of the effects of resveratrol on cell growth, hydrogen peroxide production, and mitochondrial network characteristics that were seen in 25 mM glucose and/or 18% oxygen were absent under the physiologically relevant conditions of 5 mM glucose with 5% oxygen. These findings emphasize the importance of using physiologically meaningful starting conditions for cell-culture experiments with resveratrol and indeed any manipulation affecting ROS metabolism and mitochondria.
Keywords: Warburg; glycolysis; metabolism; mitochondria; mitochondrial dynamics; reactive oxygen species; resveratrol.