Determination of mitochondrial reactive oxygen species: methodological aspects

Abstract

The generation of Reactive Oxygen Species (ROS) as by-products in mitochondria Electron Transport Chain (ETC) has long been admitted as the cost of aerobic energy metabolism with oxidative damages as consequence. The purpose of this methodological review is to present some of the most widespread methods of ROS generation and to underline the limitations as well as some problems, identified with some experiments as examples, in the interpretation of such results. There is now no doubt that besides their pejorative role, ROS are involved in a variety of cellular processes for the continuous adaptation of the cell to its environment. Because ROS metabolism is a complex area (low production, instability of species, efficient antioxidant defense system, several places of production…) bias, variances and limitations in ROS measurements must be recognized in order to avoid artefactual conclusions, and especially to improve our understanding of physiological and pathophysiological mechanisms of such phenomenon.

Mapping Key Residues of ISD11 Critical for NFS1-ISD11 Subcomplex Stability

“…Notably, we also observed a significant enhancement of ROS levels in the R68A/R68L mutant mitochondria in both model systems. This is probably due to the loss of ETC complex activity, causing leakage of free electrons during electron transport and producing superoxide radicals (43)(44)(45). Additionally, enrichment of the reduced form of iron in the mitochondria leads to production of superoxide radicals and highly toxic hydroxyl radicals through Fenton's reaction (46,47).…”

Optical and pharmacological tools to investigate the role of mitochondria during oxidative stress and neurodegeneration

“…For example, the selectivity of HEt for · O 2 − (Bindokas et al, 1996) and that of dichlorofluorescein (DCF) derivatives and DHR123 for H 2 O 2 has been questioned in several studies (Batandier et al, 2002;Possel et al, 1997;Royall and Ischiropoulos, 1993). Another disadvantage is the extremely short lifetime of · O 2 − (<1 μs) and OH · , which cause H 2 O 2 and ONOO − to be the primary detectable ROS.…”

Intracellular chemiluminescence activates targeted photodynamic destruction of leukaemic cells

“…These include a variety of signalling pathways (Finkel, 1998) and intracellular iron metabolism (Caltagirone et al, 2001). Also, reactive oxygen species such as O 2 * produced in mitochondria by the electron transport chain are dismuted to H 2 O 2 (Batandier et al, 2002), which diffuses into the cytoplasm (Antunes and Cadenas, 2000). Oxidant products of nitric oxide have also been shown to activate luminal (Catz et al, 1995).…”