1. Mitochondria: The dynamics of fu

1. Mitochondria: The dynamics of functions and dysfunctionsMitochondria are eukaryotic cell organelles that arguably evolved from a symbioticrelationship between aerobic microbes and primordial eukaryotic cells (Chan, 2006; Sagan,1967; Selosse, 2011). They putatively produce energy (ATP) through oxidativephosphorylation (OX-PHOS) by transporting electrons across multiple internal complexes(mitochondrial complexes I-V) of an electron transport chain (ETC) (Das and Guha 2010;Kaurola et al., 2016). These double-membrane organelles maintain their redox potential bypumping protons across their inner membrane (Chan, 2006). Mitochondria are involved inmetabolism of glucose (Krebs cycle) and fatty acids (β-oxidation), and are also associated withcalcium homeostasis (Schon and Przedborski, 2011; Palomo and Manfredi, 2015).Furthermore, they play a crucial role in apoptosis, which is triggered by the release ofcytochrome c and apoptosis-inducing factor (AIF) from the mitochondria into the cytoplasm(Frank et al., 2001; Herold et al., 2002; Faridi et al., 2016; Zhao et al., 2016). Mitochondrialredox reactions produce reactive oxygen species (ROS) (such as superoxides, peroxides,hydroxides and singlet oxygen) and reactive nitrogen species (RNS) (peroxynitrites anddinitrogen trioxide), which might impair the ETC and cell cycle progression (Das and Guha2010; Quijano et al., 2016).