Antioxidants protect cells from damage caused by oxidative and electrophilic stress by scavenging superoxide, binding metal ions or by regenerating other oxidized antioxidants. Evidence suggests the pathological role of free radicals in a variety of diseases, the most important are atherosclerosis, chronic inflammation, and cancer. Human plasma contains many different nonenzymatic antioxidants. Centrally active antioxidants may reduce neuronal damage in pathologic conditions associated with excessive Glu release. Dietary antioxidants take part in cellular reduction-oxidation reactions in which they can act as either antioxidants (electron donors) or prooxidants (electron acceptors), depending on the physiological conditions and general oxidative state.
Phenolic antioxidants (PA) inhibit the induction of inflammatory cytokines by inflammatory stimuli. The broad spectrum of PA functions suggests that the antioxidants have multiple targets.
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