Translational Metabolism Research Laboratory

The increase in reactive oxygen species (ROS) production during exercise is well established. However, the specific consequences that an increase in contraction-induced ROS has on cellular function and/or adaptation are not completely understood. An earlier notion that portrayed exercise-induced ROS formation as a necessary evil of muscular contraction, resulting in deleterious effects such as protein or lipid damage, has been transformed over the past several decades into a hormetic effect of exercise-induced ROS signifying that limited exposure to ROS is beneficial whereas a greater, uncontrolled, exposure is harmful. Recent evidence suggests that the acute and transient increase in ROS during muscular contraction is directly involved in the up-regulated expression of endogenous antioxidants, the control of redox-sensitive transcription factors, and the stimulation of mitochondrial biogenesis. Although there is ample evidence that indicates the involvement of ROS in modulation of cell signalling pathways, many questions specific to redox biology remain unanswered