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Updated: Apr 16, 2026

Simultaneous Measurement of Superoxide/Hydrogen Peroxide and NADH Production by Flavin-containing Mitochondrial Dehydrogenases
Published on: February 24, 2018
Oxidation of H2S in mammalian cells and mitochondria
Abbas Abou-Hamdan1, Hala Guedouari-Bounihi1, Véronique Lenoir1
1Inserm U1016, Institut Cochin, Paris, France; CNRS UM8104, Institut Cochin, Paris, France; Université Paris Descartes UMR-S1016, Institut Cochin, Paris, France.
Abstract:
Hydrogen sulfide (H2S) is the third gasotransmitter described in mammals. These gasotransmitters (H2S, CO, and NO) are small molecules able to diffuse freely across membranes and thus susceptible to reach easily intracellular targets, one of which is the respiratory enzyme cytochrome oxidase subject to complete inhibition by low micromolar concentrations of these gases. However in contrast to NO or CO, H2S can be metabolized by a sulfide quinone reductase feeding the mitochondrial respiratory chain with the hydrogen atoms of sulfide. Sulfide is thus a two-sided molecule: substrate or poison according to the concentration. The aim of this chapter is to present a mean to monitor sulfide oxidation by isolated mitochondria or cells and to summarize how the properties of this amazing couple (mitochondria and sulfide) translate into practical and conceptual consequences.
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