title: Changes in photoinduced cutaneous erythema with topical application of a combination of vitamins C and E before and after UV exposure.
abstract: BACKGROUND
  Ultraviolet radiation is harmful for human skin, and photodamaging pathologies such as actinic erythema, are formerly described as a consequence of UV direct effect on DNA and indirectly by local immune reactions. However, the degree of participation of oxidative stress in actinic erythema and the role of antioxidants in photoprotection are still not fully understood.
  
  
  OBJECTIVE
  To evaluate the possible palliative role of a combination of the antioxidants vitamins C and E in human cutaneous erythema when applied topically before and after UV exposure.
  
  
  METHODS
  The study included 20 volunteers of phototypes II, II-III and III with no solar exposure for two months prior to the study. The volunteers were submitted to a phototest consisting on the analysis of the minimal erythemal dose (MED) under different treatments: 1. Untreated irradiated skin; 2. Irradiated skin previously treated with vehicle; 3. Irradiated skin previously treated with a combination of vitamins (2.5% vit E-5% vit C); and 4. Skin treated with the antioxidant combination after irradiation. Cutaneous erythema was evaluated 24h after exposure and the MED was calculated for each treatment.
  
  
  RESULTS
  The application of vehicle did not significantly affect the MED compared to untreated irradiated skin. Application of the antioxidant combination, prior to irradiation, increased the MED in all phototypes compared with untreated irradiated skin with an average increase of 36.9%. Antioxidants applied after exposure promoted an average increase of the MED by 19.8%.
  
  
  CONCLUSIONS
  Combination of topical antioxidants (vitamins C and E) shows photoprotection activity against erythema, mainly owing to their high absorption properties. Moreover, their antioxidant activity could be considered as additive, and independent of their optical properties.
authors.affiliation: Photobiological Dermatology Laboratory, Medical Research Center, Department of Dermatology and Medicine, Faculty of Medicine, University of Malaga, Campus Universitario de Teatinos s/n, E-29071, Malaga, Spain. jaguilera@uma.es
authors.forename: José
authors.initials: J
authors.lastname: Aguilera
authors.forename: María Victoria
authors.initials: MV
authors.lastname: de Gálvez
authors.forename: Cristina
authors.initials: C
authors.lastname: Sánchez
authors.forename: Enrique
authors.initials: E
authors.lastname: Herrera-Ceballos
mesh_terms: D000287:Administration, Topical; D000328:Adult; D000975:Antioxidants / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D001205:Ascorbic Acid / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D004890:Erythema / Q000188:drug therapy* / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress / Q000187:drug effects; D012867:Skin / Q000528:radiation effects; D016896:Treatment Outcome; D014466:Ultraviolet Rays / Q000009:adverse effects*; D014810:Vitamin E / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D000975:Antioxidants; D014810:Vitamin E; D001205:Ascorbic Acid