Role of free Radicals

Aging

Aging is a process, which involves the accumulation of changes, which can be attributed to genetic defects, the environment, disease and also the inborn aging process. Many pathological conditions are associated with this process, including the development of cataracts, diabetes and macular degeneration. Ageing is thought to be caused by free radical reactions, generated in the mitochondria, which accumulate with age. Free radicals cause the progressive oxidation of protein and lipid components in the cell membranes and also activate phospholipases, proteases and endonucleases. Increased lipid peroxidation has been implicated in the ageing process followed by an induction of detoxification enzymes. Wrinkle formation in the skin has also been attributed to long-term exposure to oxidative damage light, resulting in the production of free radicals.

Some studies have shown that free radical chain reactions are associated with the aging process. These chain reactions may be decreased by increasing the intake of components, which enhances antioxidant capacity, e.g. fruits and vegetables, or by supplementing the diet with antioxidants, e.g. vitamin E, C and ß-carotene. The skin has developed complex defense mechanism, to combat long-term exposure to ROS, such as antioxidant enzymes and low molecular weight antioxidants. The activities of antioxidant enzymes in wrinkles is decreased significantly through oxidative stress and aging. As a result of the research in this field many cosmetic companies now add antioxidant components such as vitamin E to their products to protect the skin from free radical damage.

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