Reactive Oxygen Species (ROS) and Their Sources
Start with the big picture
ROS include superoxide, hydrogen peroxide, hydroxyl radical, singlet oxygen, and peroxyl radicals. Their sources range from electron leakage in the mitochondrial electron transport chain to enzyme systems such as cytochrome P450, NADPH oxidase, xanthine oxidase, and peroxisomal oxidases. Metal-catalyzed reactions can convert hydrogen peroxide into the highly reactive hydroxyl radical, while auto-oxidation and inflammatory enzymes contribute additional reactive products. Radiation, UV light, pollutants, and redox-cycling drugs or toxins are among the external contributors. The lesson also considers how reperfusion, mitochondrial dysfunction, and altered redox conditions can amplify ROS production, linking their origins to potential cellular injury.
What you'll learn
- Identify the major reactive oxygen species described in the topic.
- Explain key mitochondrial and enzyme-related sources of cellular ROS.
- Distinguish endogenous ROS sources from environmental and drug-related sources.
- Describe how metal-catalyzed reactions can generate hydroxyl radicals.
- Relate ischemia-reperfusion and mitochondrial dysfunction to increased ROS production.
Continue your study
Work through the complete notes and reinforce the topic with the study tools available in the full lesson.
