title: Relation between mitochondrial membrane potential and ROS formation.
abstract: Mitochondria are considered as the main source of reactive oxygen species (ROS) in the cell. For this reason, they have been recognized as a source of various pathological conditions as well as aging. Chronic increase in the rate of ROS production is responsible for the accumulation of ROS-associated damages in DNA, proteins, and lipids, and may result in progressive cell dysfunctions and, in a consequence, apoptosis, increasing the overall probability of an organism's pathological conditions. The superoxide anion is the main undesired by-product of mitochondrial oxidative phosphorylation. Its production is triggered by a leak of electrons from the mitochondrial respiratory chain and the reaction of these electrons with O(2). Superoxide dismutase (MnSOD, SOD2) from the mitochondrial matrix as well as superoxide dismutase (Cu/ZnSOD, SOD1) present in small amounts in the mitochondrial intramembrane space, convert superoxide anion to hydrogen peroxide, which can be then converted by catalase to harmless H(2)O. In this chapter, we describe a relation between mitochondrial membrane potential and the rate of ROS formation. We present different methods applicable for isolated mitochondria or intact cells. We also present experiments demonstrating that a magnitude and a direction (increase or decrease) of a change in mitochondrial ROS production depends on the metabolic state of this organelle.
authors: Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland.
authors: Jan M
authors: JM
authors: Suski
authors: Magdalena
authors: M
authors: Lebiedzinska
authors: Massimo
authors: M
authors: Bonora
authors: Paolo
authors: P
authors: Pinton
authors: Jerzy
authors: J
authors: Duszynski
authors: Mariusz R
authors: MR
authors: Wieckowski
mesh_terms: D000818:Animals; D001562:Benzimidazoles / Q000378:metabolism; D001921:Brain / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D002232:Carbocyanines / Q000378:metabolism; D002286:Carcinoma, Ehrlich Tumor / Q000378:metabolism; D002458:Cell Fractionation / Q000379:methods; D045744:Cell Line, Tumor; D004579:Electron Transport; D005347:Fibroblasts / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D053078:Membrane Potential, Mitochondrial; D051379:Mice; D018613:Microscopy, Confocal; D008928:Mitochondria / Q000378:metabolism*; D010101:Oxygen Consumption; D010619:Phenazines / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013481:Superoxides / Q000378:metabolism
chemical_list: D001562:Benzimidazoles; D002232:Carbocyanines; D010619:Phenazines; D017382:Reactive Oxygen Species; D013481:Superoxides; C068624:5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolocarbocyanine; D006861:Hydrogen Peroxide; D002118:Calcium; C009195:safranine T