Effectiveness of antioxidants (vitamin C and E) with and without sunscreens as topical photoprotectants.
Considerable interest has been recently generated concerning the use of natural compounds, anti-oxidants in particular, in photoprotection. Two of the best known anti-oxidants are vitamins C and E, both of which have been shown to be somewhat effective in different models of photodamage. Very little has been reported, however, on the effectiveness of a combination of the two (known to be biologically the more relevant situation); nor have there been detailed studies on the ability of these antioxidants to augment commercial sunscreen protection against UV damage. We report that (in swine skin) vitamin C is capable of additive protection against acute UVB damage (sunburn cell formation) when combined with a UVB sunscreen. A combination of both vitamins E and C provided very good protection from a UVB insult, the bulk of the protection attributable to vitamin E. However, vitamin C is significantly better than vitamin E at protecting against a UVA-mediated phototoxic insult in this animal model, while the combination is only slightly more effective than vitamin C alone. When vitamin C or a combination of vitamin C and E is formulated with a commercial UVA sunscreen (oxybenzone), an apparently greater than additive protection is noted against the phototoxic damage. These results confirm the utility of anti-oxidants as photoprotectants but suggest the importance of combining the compounds with known sunscreens to maximize photoprotection.
Darr
D
D
North Carolina Biotechnology Center, Raleigh, N.C., USA.
Dunston
S
S
Faust
H
H
Pinnell
S
S
D000279:Administration, Cutaneous; D000818:Animals; D000975:Antioxidants / Q000008:administration & dosage / Q000627:therapeutic use*; D001205:Ascorbic Acid / Q000008:administration & dosage / Q000627:therapeutic use*; D001577:Benzophenones / Q000008:administration & dosage / Q000627:therapeutic use; D002482:Cellulose / Q000031:analogs & derivatives; D003879:Dermatologic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D004195:Disease Models, Animal; D004338:Drug Combinations; D004357:Drug Synergism; D008297:Male; D014677:Pharmaceutical Vehicles; D019946:Propylene Glycol; D011409:Propylene Glycols; D011835:Radiation Protection; D012867:Skin / Q000473:pathology / Q000528:radiation effects; D015595:Skin Aging / Q000187:drug effects / Q000473:pathology; D013471:Sunburn / Q000209:etiology / Q000473:pathology / Q000517:prevention & control; D013473:Sunscreening Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D013552:Swine; D014466:Ultraviolet Rays / Q000009:adverse effects / Q000145:classification; D014810:Vitamin E / Q000008:administration & dosage / Q000627:therapeutic use*
D000975:Antioxidants; D001577:Benzophenones; D003879:Dermatologic Agents; D004338:Drug Combinations; D014677:Pharmaceutical Vehicles; D011409:Propylene Glycols; D013473:Sunscreening Agents; D014810:Vitamin E; D019946:Propylene Glycol; D002482:Cellulose; C005290:oxybenzone; C008079:hydroxypropylcellulose; D001205:Ascorbic Acid