Related Experiment Video
Updated: Apr 17, 2026
Simultaneous Measurement of Superoxide/Hydrogen Peroxide and NADH Production by Flavin-containing Mitochondrial Dehydrogenases
Published on: February 24, 2018
Mitochondria: Much ado about nothing? How dangerous is reactive oxygen species production?
Eliška Holzerová1, Holger Prokisch1
1Institute of Human Genetics, Technische Universität München, Munich, Germany; Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany.
Abstract:
For more than 50 years, reactive oxygen species have been considered as harmful agents, which can attack proteins, lipids or nucleic acids. In order to deal with reactive oxygen species, there is a sophisticated system developed in mitochondria to prevent possible damage. Indeed, increased reactive oxygen species levels contribute to pathomechanisms in several human diseases, either by its impaired defense system or increased production of reactive oxygen species. However, in the last two decades, the importance of reactive oxygen species in many cellular signaling pathways has been unraveled. Homeostatic levels were shown to be necessary for correct differentiation during embryonic expansion of stem cells. Although the mechanism is still not fully understood, we cannot only regard reactive oxygen species as a toxic by-product of mitochondrial respiration anymore. This article is part of a Directed Issue entitled: Energy Metabolism Disorders and Therapies.
Insights
Reactive oxygen species (ROS) were long seen as harmful, but new research shows their crucial role in cell signaling and stem cell differentiation. ROS are vital for cellular functions, not just toxic byproducts.
Area of Science:
- Biochemistry
- Cell Biology
- Mitochondrial Function
Background:
- Reactive oxygen species (ROS) traditionally viewed as damaging agents attacking cellular components.
- Mitochondria possess defense systems against ROS, with elevated levels implicated in human diseases.
- Recent findings highlight ROS's essential role in cellular signaling pathways.
Purpose of the Study:
- To re-evaluate the role of reactive oxygen species beyond their toxic effects.
- To explore the significance of ROS in cellular signaling and stem cell biology.
- To understand the dual nature of ROS in health and disease.
Main Methods:
- Literature review on reactive oxygen species.
- Analysis of mitochondrial function and ROS production.
- Examination of ROS in cellular signaling and differentiation processes.
Main Results:
- ROS are implicated in cellular signaling pathways, not solely as toxic byproducts.
- Homeostatic ROS levels are essential for embryonic stem cell differentiation.
- Mitochondrial ROS defense systems are critical for preventing cellular damage.
Conclusions:
- Reactive oxygen species have a dual role, acting as signaling molecules and potential toxins.
- Understanding ROS homeostasis is crucial for stem cell biology and disease mechanisms.
- The perception of ROS has shifted from purely harmful agents to essential signaling molecules.
Related Concept Videos
01:43Electron Transport Chain: Complex III and IV
01:45Mitochondrial Membranes
01:30Peroxisomes and Mitochondria
The peroxisome is a single membrane-bound cellular organelle that can perform several different functions, including lipid metabolism and chemical detoxification. The enzymes within...
01:37Mitochondria
01:37Mitochondria
01:15Pyruvate Oxidation
First, the enzyme pyruvate dehydrogenase removes the carboxyl group from pyruvate and releases it as carbon dioxide. The stripped molecule is then oxidized and releases electrons, which are then picked up by NAD+...