Reactive oxygen species

Reactive oxygen species (ROS) are small unstable, highly reactive molecules with a short half-life derived by reduction of molecular oxygen. Once generated, ROS influence signalling molecules, in part through post-translational oxidative modification of proteins, modulating cellular function. These species are produced in all vascular cell types and have emerged as key second messengers in cellular events in the vasculature. ROS are involved in vascular contraction and relaxation, cell growth, migration, differentiation, survival and apoptosis. In pathological conditions, increased ROS generation is associated with oxidative stress and inflammation leading to dysregulation of vascular cell function and consequent vascular injury underlying cardiovascular diseases