oa Editorial [Hot Topic: Mitochondria as a Drug Target in Health and Disease (Guest Editor: Paulo J. Oliveira)]

The breath of life that runs inside our cells starts within mitochondria. In fact, complex life without mitochondria would not be possible due to the multitude of functions in which these organelles participate. From the production of energy, to the control of cell death pathways (yes, what feeds you can also kill you…), calcium homeostasis, intracellular signaling and intermediate metabolism, mitochondria are remarkable dynamic structures, with an important, yet undesirable, role as mediator of several disease processes. Moreover, mitochondria are also involved in the toxicity of several xenobiotics, which are known to cause harm to humans and interestingly, several idiosyncratic drug reactions are known to be mediated, at least in part by mitochondrial toxicity. It is of course expected that drug or disease-induced mitochondrial dysfunction will impact more organs with higher energy requirements, such as the cardiac and skeletal muscles and the central nervous system. If mitochondrial dysfunction can contribute to organ degeneration, then aiming at the protection of mitochondrial function should be a priority to rescue the affected organ, which is something that is easier said than done. Thus, it is clear that mitochondria are important drug targets in both health and disease. Several clinically used drugs target mitochondria, which provide the basis for their pharmacological and/or toxicity effects. The dual role of mitochondria in drug effects is the objective of this special edition of Current Drug Targets entitled “Mitochondria as a Drug Target in Health and Disease”. Thirteen nicely done papers compose this special edition, written by well-known researchers in the field of mitochondrial toxicology and disease. Different topics are covered in this special issue including a) the description of multiple techniques that can be used to derive instructive functional indicators of neuronal mitochondrial function and damage, b) the role of mitochondrial testing in drug development and safety, c) induction of mild mitochondrial membrane potential uncoupling as a therapeutic strategy, d) the role of mitophagy in neurodegeneration during health and disease, e) use of mitochondrial-directed agents to prevent dysfunction and reverse disease, f) mitochondrial tolerance to drugs and toxic agents in ageing and disease, g) the alkaloid berberine as a possible anti-cancer mitochondrial-mediated agent, h) mitochondria as a target for exercise-induced cardioprotection, i) the role of mitochondrial dynamics and biogenesis in metabolic syndrome, j) the role of mitochondria in the pathogenesis of liver diseases, k) targeting the mitochondrial adenine nucleotide translocator 2 during anti-cancer therapy and last but not least, l) the interplay between Casein Kinase II and mitochondrial-mediated apoptosis in cancer cells. It was a pleasure and an honor to be able to unite such outstanding pieces of work on our favorite organelle…mitochondria. Hope the reader agrees with me.