Free radicals are generated by the transfer of energy and the creation of molecules with an unpaired electron that is seeking a partner. These are high-energy, reactive intermediate compounds that will react with oxygen.
Free radicals may be generated by ionizing radiation energy, ultraviolet light such as from sunlight or other light sources, smoking, inflammation, air pollution, or metabolism within the cell. Reactive oxygen species include hydrogen peroxide, an intermediate compound, and other free-radical compounds such as hydroxyl compounds, singlet and triplet oxygen, superoxide, and nitric oxide.
These molecules then can cause damage to lipids, proteins, and DNA. The damaging effects may include decreased cell enzyme activity, membrane damage, mutation of DNA, increased cell turnover, cell injury, or cell death. These changes lead to aging of the biological system.
Ultimately, if left unchecked, the damages from unchecked reactive oxygen species may be related to cancer, atherosclerosis, inflammatory diseases, Alzheimer’s disease, Parkinson’s disease, emphysema, cataracts, and macular degeneration. The scientific literature relating to this area of free radicals and oxidation in relation to health is expanding rapidly.
Free radicals also cause damage to other systems, such as foods, resulting in decreased flavor and odor quality, changes in color stability, and loss of nutrients needed for nutritional purposes. Changes in flavor and odor quality of foods can mean a decreased consumption pattern.
This may be the case when milk is subjected to light oxidation, with the resulting poor flavor and odor causing decreased acceptance and declining milk consumption. The indirect impact of the lower consumption of milk is the loss of important nutrients in milk, such as calcium, phosphorus, vitamins A and D and riboflavin, and valuable milk proteins in the diet. Riboflavin structure is altered by reaction with light and the vitamin activity is lost, thus resulting in a decreased bioactivity even when the light-oxidized milk is consumed.
Horses with recurrent airway obstruction (RAO) exhibit symptoms similar to human asthma including cellular oxidation and inflammation.
Researchers have developed an antioxidant delivery system to target specific cell receptors present in the lower airways of RAO-affected horses.
They are also planning to conduct a pilot study to investigate the targeting and uptake of an aerosol formulation administered using a nebulizer.
Therapeutic treatments similar to this design may have useful application for both human and animals affected with respiratory diseases and conditions.
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