Oxidative Stress Overview

Uncontrolled reactions that damage proteins by forming reactive byproducts. These reactions occur in chains.

A major source of free radicals (ROS) that damage cells. Problems in mitochondria lead to increased ROS production.

Free radicals attack lipids in cell membranes, changing fluidity and disrupting cell signaling.

Oxidative damage to DNA can lead to replication errors and mutations.

Lack of antioxidants reduces the body's ability to combat free radicals.

Reactive oxygen species (ROS) are highly reactive molecules containing oxygen. They are byproducts of normal metabolism and play a role in cell signaling. However, excessive ROS accumulation can cause oxidative stress and damage cells.

Oxidative stress occurs when the production of reactive oxygen species (ROS) overwhelms the body's antioxidant defense mechanisms. This imbalance leads to cellular damage, contributing to aging and disease.

The superoxide radical (O₂⁻·) is a type of ROS. It's generated during normal metabolic processes and is relatively weak. Its limited reactivity makes it less damaging than other ROS.

Hydrogen peroxide (H₂O₂ ) is another type of ROS, generated from superoxide radicals. It can penetrate cell membranes and even generate more harmful hydroxyl radicals under certain conditions.

Beta-oxidation is a metabolic process where fatty acids are broken down to produce energy. However, this process can generate some ROS as side products.

A highly reactive molecule that can damage macromolecules, including proteins, lipids, and DNA.

A type of reactive oxygen species (ROS) produced during photooxidation. It is a form of oxygen with a higher energy level than ground state oxygen.

Enzymes that break down hydrogen peroxide (H₂O₂) into water and oxygen, protecting cells from oxidative damage.

The process of damaging proteins due to oxidation, leading to loss of function and increased degradation.

A buildup of fatty deposits in the artery walls, often caused by oxidative stress damaging the endothelial cells lining the arteries.

Enzymes that repair damaged DNA caused by reactive oxygen species (ROS).

The initial ROS formed during energy production. It is a highly reactive form of oxygen with an extra electron.

A key organelle in cells responsible for generating energy. It is a major source of ROS.

Decreasing caloric intake reduces metabolic rate and slows the production of ROS.

The process of producing energy without oxygen, which leads to lactate buildup and a decrease in pH. It also generates a small percentage of ROS.

An observation that organisms that produce less ROS tend to live longer. It is a theory that explains the link between ROS and aging.

A defense system that protects against oxidative stress by using enzymes like proteases and nucleases to repair damaged molecules.

Can be a result of oxidative stress, leading to mutations and errors during DNA replication. This can affect animal health and productivity.

A type of chemical that can trigger ROS production in the body, leading to oxidative stress.

Molecules in the diet like vitamins C and E that can counteract the effects of ROS and promote overall health.

High levels of oxygen can overwhelm antioxidant defenses, leading to oxidative stress and cell damage.

A process that occurs after a period of ischemia (lack of blood flow), where oxygen is reintroduced to the affected area. This can lead to increased ROS production and further damage.

Substances that protect cells and tissues from the damaging effects of ROS. They work by neutralizing or scavenging ROS.

The process of restoring ATP levels following ischemia. This process can paradoxically generate additional ROS, contributing to reperfusion injury.

A condition where the blood supply to a tissue or organ is blocked, leading to a lack of oxygen and nutrients. This can cause cell damage and death.

The lining of blood vessels. ROS can damage the endothelium, making it more permeable to lipoproteins (fats) which can contribute to atherosclerosis.