Fig 1. Mitochondrial dysfunction may lead to oxidative damage of macromolecules.
Genetic mutations or environmental factors inhibit complex I activity and/or result in mitochondrial impairment. Mitochondrial dysfunction produces ROS. The resultant ROS may damage macromolecules, including nucleic acids, lipids and proteins. An oxidized macromolecule can then damage another macromolecule, leading to a vicious cycle of oxidized products.