Initiation and Prevention of Biological Damage by Radiation-Generated Protein Radicals

Abstract

Ionizing radiations cause chemical damage to proteins. In aerobic aqueous solutions, the damage is commonly mediated by the hydroxyl free radicals generated from water, resulting in formation of protein radicals. Protein damage is especially significant in biological systems, because proteins are the most abundant targets of the radiation-generated radicals, the hydroxyl radical-protein reaction is fast, and the damage usually results in loss of their biological function. Under physiological conditions, proteins are initially oxidized to carbon-centered radicals, which can propagate the damage to other molecules. The most effective endogenous antioxidants, ascorbate, GSH, and urate, are unable to prevent all of the damage under the common condition of oxidative stress. In a promising development, recent work demonstrates the potential of polyphenols, their metabolites, and other aromatic compounds to repair protein radicals by the fast formation of less damaging radical adducts, thus potentially preventing the formation of a cascade of new reactive species.

Antioxidative and Anti-Inflammatory Activity of Ascorbic Acid

“…Thus, the protective properties of ascorbate (1 g/day) are based on the elimination of the action of various proteasome inhibitors [ 104 , 105 ] and the promotion of the removal of oxidatively damaged proteins from the cytoplasm of cells ( Figure 2 ). Unfortunately, the protective action of ascorbate against protein oxidation with the formation of protein radicals is strictly dependent on the ascorbate concentration, which is often insufficient in tissues in vivo (physiological conditions) [ 106 , 107 , 108 ].…”

Integrated electron beam irradiation treatment with hydrogen peroxide aqueous solution to inactivate Salmonella on grape tomatoes

“…The hydroxyl radical has one unpaired electron, so that it can deprive other substances of an electron by oxidation. Hence, damage to microbial DNA or proteins is mostly oxidative in nature (Gebicki & Nauser, 2022; Singh & Singh, 1982).…”

Using integrated GC-MS analysis, in vitro experiments, network pharmacology: exploring migao fatty oil active components/mechanisms against coronary heart disease

“…Fatty acids, present in fatty oils, have special lipophilic and electron-stabilizing properties that make them a promising class of natural medical antioxidants (Sherratt & Mason, 2018). By quickly forming less harmful free radical compounds, protein free radical damage can be rapidly repaired, avoiding the emergence of cascades of new reactive species and therefore avoiding atherosclerosis and coronary heart disease (Gebicki & Nauser, 2021).…”