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Save thy skin

Save thy skin THE sun's bright rays can play havoc with one's flawless skin. Sun bathing for as short a period as two to three minutes can lead to tissue damag~ and prema- ture aging of the human skin. A te~ of researchers at the University of Michigan, us, headed by Gary Fisher, carried out an interesting experiment in which the bottoms of adult subjects were exposed to ultraviolet-B (UV-B) light (rays pre~ent in the sunlight that are known to damage skin). The skin in this part of the body was the best to ascertain the effects of ultra- violet rays as it is alIpost never exposed to sunlight. At regular intervals, patches of skin from the area were removed and subjected to a series of biochemical tests. It was found that even a very short exposure to the warm sun triggers a cascade of powerful enzymes that break down collagen and elastin, the two main structural proteins in the s~n that help keep it smooth and supple.

The UV-B rays of the sun also hasten the wrinkling and mottling of skin. Scientists report that skin which is repeatedly exposed to ultraviolet light, particularly UV-B rays, undergoes an additional process called photoaging apart from the normal process of aging. The process accelerates the normal rate of aging and adds some new problems including a reduction in the number of immune system cells in the skin and an increased risk of skin cancer.

But there is hope for those who cannot resist basking in the sun. Tretinoin -a cl}emical cousin of vitamin A -is believed to be good at preventing sun-induced damage and aging. The chemical is the main ingre- dient of retin-A and renova, skin creams manufactured by the Ortho Pharma- ceutical Corporation, a division of the New Jersey-based Johnson & Johnson, in the us. Although retin-A is an acne cream, it has gained reputation as an anti-wrinkle cream. Renova, which was recently approved by the us Food and Drug Administration (FDA), has been tested for its ability to reduce fine facial wrinkles, brown spots and surface roughness found on sun-exposed skin. The University of Michigan team which tried renova on 660 patients, found that about 80 per cent could control fine wrinkling, while 65 per cent were able to reduce the number of brown spots, and about half of ~em could smoothen out their rough skins.

However, this miracle cream neither erases coarse or deep wrinkles nor can it remedy skin yellowed by sun damage, or cure deeply pigmented , skin: Moreover, aword of caution is being added for women who are pregnant, nursing or trying to conceive because renova could induce defects in the baby. "Tretinoin and birth defects have never been causally linked, but we want to control factors that could be potential problems," says Tabitha Henderson, a dermatologist working for the Ortho Pharmaceutical Corporation.

Meanwhile, Douglas E Brash of Yale University and Barbara Gilchrest of the University of Boston question the use of Tretinoin. The chemical works by shutting down two genes inside one's skin ,cells which unde~ normal conditions get activated by ultraviolet light and produce enzymes that destroy collagen and elastin. Sceptics point out that these two genes may be responsible for bringing' about other skin reactions like healing wounds and preventing skin cancer . "People should think twice before making such important genetic switches for a prolonged period of time", warn these researchers.

Interestingly, even the FDA is not sure whether renova is safe if used for more than 48 weeks. While researchers debate the decision to use this wonder cream, one thing' goes beyond doubt ~ if you venture too often in the sun, the mirror on the wall will surely hesitate calling you the fairest of them all.

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