Figure 3.

Generation and detoxification of ROS. ROS is an important signal that impacts heat generation, insulin secretion, appetite control and fuel storage when controlled but causes oxidative stress, DNA damage and cell death when excessive. In addition to ROS produced in the electron transport chain in response to excess fuel, ROS is also generated by several mitochondrial dehydrogenases and cellular oxidases. Detoxification or ROS removal involves a variety of processes in multiple compartments. In the mitochondria NNT and peroxidases dominate and in the cytosolic and microsomal compartments peroxidases, the pentose phosphate pathway, catalase and redoxins all play important roles. The mechanisms by which obesogens increase ROS are not yet defined nor is it known whether they effect the generation or detoxification of ROS. (Online version in colour.)