Title:Antioxidants in the Practice of Medicine; What Should the Clinician Know?
Volume: 16
Issue: 1
Author(s): Thomas F. Whayne, Sibu P. Saha and Debabrata Mukherjee
Affiliation:
Keywords:
Antioxidants, free radicals, hydrogen peroxide, oxidative stress, reactive oxygen species, thioredoxin.
Abstract: Antioxidants offer protection against the damage potentially caused by free
radicals, which usually involve an oxygen or nitrogen moiety, in living organisms.
An antioxidant can be defined as a molecule that has the capability to inhibit the
oxidation of another molecule, so, in other words, it is a reducing agent that is
sufficiently stable to donate an electron to a circulating free radical and thereby result
in its neutralization. Free radicals can be defined as any chemical species that has one
or more mismatched electrons; these free radicals can cause a sequential reaction
resulting in damage to multiple components of the organism, functioning either as an
oxidant or a reductant by accepting or donating an electron, respectively. Oxidative
stress can be defined as an imbalance between the production of free radicals and
necessary antioxidant defenses. Therefore protection of the organism from these potentially damaging
entities, when appropriate, is essential. Potential damage involves lipids, proteins, cell membranes,
deoxyribonucleic acid (DNA), carbohydrates, and various enzymes, which can lead to cell death.
Antioxidant protection from free radical-induced damage occurs via the donation of an electron with
subsequent conversion of a free radical to a harmless chemical configuration that can no longer damage a
cell and its components. Classes of antioxidants include, natural, nutrient, and supplemental. When
antioxidant levels are low, there is a resultant increase in oxidative stress with a harmful increase in free
radicals that can be associated with an increased risk for cardiovascular (CV) disease including
atherosclerosis, various inflammatory diseases, and cancer. Major issues for the clinician to consider are
what can be done to naturally increase antioxidants when deficient or when a directed increase might be
beneficial such as in aging and degenerative disease, how nutrients can be altered or provided to increase
antioxidant protection, and when or if to consider the use of supplements, frequently classified as
alternative medicines.
