Mitochondrial toxicity induced by plant molecules

Abstract Plants produce thousands of molecules, which are toxic to animal cells, used as a deterrent against herbivores. Many of these compounds exert their effects by interfering with mitochondrial functions, and in particular with tricarboxylic acid (TCA) cycle, electron chain transport (ETC), and oxidative phosphorylation (OXPHOS). The toxic effect is exerted either directly, by inhibiting key enzymes or multiprotein complexes, or indirectly, by causing the overproduction of molecules normally present in mitochondria such as reactive oxygen species, which could in turn damage mitochondrial components. In this chapter, we discuss why mitochondria could represent a preferable target for toxic molecules, the preferred targets of toxic compounds produced by plants, and the main classes of molecules acting on mitochondria, focusing our attention on the mechanisms of action of some representative examples.