Mitochondria targeting by environmental stressors: implications for redox cellular signaling

Abstract

Mitochondria are cellular powerhouses as well as metabolic and signaling hubs, regulating diverse cellular functions from basic physiology to phenotypic fate determination. It is widely accepted that reactive oxygen species (ROS) generated in mitochondria participate in the regulation of cellular signaling and that there are mitochondria which operate at a high ROS baseline. However, how mitochondria adapt to persistently high ROS states as well as to environmental stressors that disturb the redox balance is not completely understood. Here we will review some of the current concepts regarding how mitochondria resist oxidative damage, how they are replaced when oxidative damage is excessive to an extent that compromises function, and what is the effect of some environmental toxicants (i.e. heavy metals) on the regulation of mitochondrial ROS (mtROS) production which are linked to their toxic effects on cells and tissues.