Collective term used by biologists to designate the oxygen radicals (e.g. O2−, OH) and certain nonradical derivatives of O2, such as hydrogen peroxide (H2O2).
Radicals derived from oxygen, including singlet oxygen, superoxide, peroxide and hydroxyl radical.
Molecules including free radicals and other oxygen species.
An unstable molecule, which may do biological damage unless stabilized by another molecule. Antioxidants can act by scavenging reactive oxygen species, by preventing their formation, or by repairing the damage that they do.
Highly reactive oxygen–containing free radicals that are generated during oxidative metabolism. ROS can react with and damage lipids, proteins, and DNA in cells, causing oxidative stress. Common ROS include hydrogen peroxide, superoxide radicals, and hydroxyl radicals.
Oxygen free radicals. High levels of ROS generation are linked a reduced ability of sperm to bind to the zona pellucida. Vitamin E may significantly improve this aspect of sperm function.
any of a number of highly reactive forms of oxygen that are potential sources of damage.
Reactive form of oxygen; oxygen radicals can cause cell damage, but can also participate in the killing of microorganisms
Chemicals like hydrogen peroxide (H2O2), superoxide (O2-), and the hydroxyl radical (OH.). Produced naturally by the human body, they contribute to the anti-microbial activity of white blood cells and control some cell signalling processes. At higher levels they can cause DNA and RNA damage.
One of several types of small molecules containing oxygen with an unstable number of electrons. Reactive oxygen species can damage many kinds of biological molecules.
Highly reactive chemicals, containing oxygen, that react easily with other molecules, resulting in potentially damaging modifications.
highly reactive oxygen molecules that have unpaired electrons in their outer shell, thus called "reactive oxygen species." ROS cause cellular damage by taking electrons from proteins, lipids and DNA by altering their chemical structure. Also referred to as free radicals. ROS can react with and damage lipids, proteins, and DNA in cells. (see free radicals)
A relatively new interest area in male infertility, ROS refers to small molecules present in many bodily fluids, such as seminal white blood and sperm cells. When in appropriate concentrations, ROS can help prepare the sperm for fertilization. However, if in excess, ROS can be harmful to other cells.Because of their already high polyunsaturated fatty acid content, human sperm membranes are particularly sensitive to ROS-related damage. Recent studies have demonstrated an increase in presence of these molecules in the semen of infertile men. Several compounds have been used to detoxify or "scavenge" ROS. The most effective of these, vitamin E (400 IU twice daily) is a very effective antioxidant.Pentoxifylline, a medication employed occasionally to decrease the thickness of blood, has also been shown to decrease sperm oxidant production, but is used much less frequently than vitamin E.
Reactive oxygen species (ROS) include oxygen ions, free radicals and peroxides both inorganic and organic. They are generally very small molecules and are highly reactive due to the presence of unpaired valence shell electrons. ROSs form as a natural byproduct of the normal metabolism of oxygen and have important roles in cell signaling.