Defining roles of specific reactive oxygen species (ROS) in cell biology and physiology

Abstract

Reactive oxygen species (ROS) is a generic term that defines a wide variety of oxidant molecules with vastly different properties and biological functions that range from signalling to causing pathological damage. Consequently, the molecular description of oxidants needs to be chemically precise for rational translation of research on their biological effects into therapeutic benefit in redox medicine. This Expert Recommendation article pinpoints key issues associated with identifying and explaining the physiological roles of oxidants, focusing on H2O2 and O2 .-. The generic term ROS should not be used as if it were describing a specific molecular agent, and greater precision in measurement of H2O2, O2 .and other oxidants, along with more specific identification of their respective signalling targets are needed. Future work should also focus more on inter-organellar communication in oxidant signalling and on the interactions of redox-sensitive signalling targets within complex biological systems, including whole organisms with their lifetime environmental exposures. To that effect, we recommend that new tools be used which enable site-specific and real-time detection and quantification of individual oxidants in cells and model organisms. We also stress that physiological O2 levels should be maintained in cell culture to better mimic in vivo redox reactions associated with specific cell types.Use of more precise definitions and analytical tools will help harmonize research among the many disciplines towards the common goal of understanding redox biology and medicine.

Nitric oxide biosensor uncovers diminished ferrous iron-dependency of cultured cells adapted to physiological oxygen levels

“…Paired cell cultures were maintained under 18 kPa O 2 or adapted to 5 kPa O 2 for 5 days in our O 2 -regulated workstations. We have previously demonstrated that cells are able to alter their redox phenotype dependent on the ambient O 2 level [ [31] , [32] , [33] , [34] ].…”

Nitric oxide biosensor uncovers diminished ferrous iron-dependency of cultured cells adapted to physiological oxygen levels

“…Critically, our study raises an important caveat about interpreting biochemical activation and functionality of metal-containing enzymes in cells cultured under standard room air conditions. Given the caveats concerning chemical uorescence probes 50 , further advances in novel genetic biosensors for high-resolution, real-time imaging of labile iron levels are warranted to enhance our understanding of iron-dependent metabolism and signaling pathways in cells under wellde ned physiological oxygen levels 51 .…”

NOX4 Mediates Epithelial Cell Death in Hyperoxic Acute Lung Injury Through Mitochondrial Reactive Oxygen Species

“…We noted that NOX4, under HO, augmented mt ROS production leading to epithelial cell apoptosis. ROS outlines diverse oxidant molecules possessing distinctive biological functions and properties and biological functions ( Sies et al, 2022 ). We focused on H 2 O 2 and O 2 .- .…”