title: Modification of skin discoloration by a topical treatment containing an extract of Dianella ensifolia: a potent antioxidant.
abstract: Skin hyperpigmentation, and the reactions that precipitate it, have been linked to free radicals by the fact that free radical scavengers or antioxidants can slow that hyperpigmentation. We have screened several hundred plant extracts for antioxidants and discovered one that is both a strong antioxidant and can reduce skin hyperpigmentation. Extracts of Dianella ensifolia contain 1-(2,4-dihydrophenyl)-3-(2,4-dimethoxy-3-methylphenyl) propane (DP), which was found to inhibit the free radical 1-1-diphenyl-2-picryl-hydrazyl (DPPH) with an EC(50) value of 78 mum. DP was also found to inhibit Ultraviolet (UV)C-induced lipid oxidation with an EC(50) of about 30 mum. We next investigated the effects of this antioxidant on skin hyperpigmentation. The reduction of discoloration by different topical treatments has been assessed in human volunteers using an in vivo assay for the rate of fading of UVB-induced tan. Two pharmaceutical formulas containing 4% hydroquinone (HQ) were used as positive controls, and we tested the ability of DP, a plant-derived amphoteric antioxidant, to increase performance of non-HQ cosmetic formulations. We found that the cosmetic formula containing DP produced an increase in the rate of fading compared to the two pharmaceutical treatments containing HQ.
authors.affiliation: Clinique Laboratories, Melville, NY, USA. tmammone@estee.com
authors.forename: Thomas
authors.initials: T
authors.lastname: Mammone
authors.forename: Neelam
authors.initials: N
authors.lastname: Muizzuddin
authors.forename: Lieve
authors.initials: L
authors.lastname: Declercq
authors.forename: Dominique
authors.initials: D
authors.lastname: Clio
authors.forename: Hugo
authors.initials: H
authors.lastname: Corstjens
authors.forename: Ilse
authors.initials: I
authors.lastname: Sente
authors.forename: Katrin
authors.initials: K
authors.lastname: Van Rillaer
authors.forename: Mary
authors.initials: M
authors.lastname: Matsui
authors.forename: Yoko
authors.initials: Y
authors.lastname: Niki
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Ichihashi
authors.forename: Paolo U
authors.initials: PU
authors.lastname: Giacomoni
authors.forename: Dan
authors.initials: D
authors.lastname: Yarosh
mesh_terms: D000287:Administration, Topical; D000328:Adult; D000975:Antioxidants / Q000494:pharmacology*; D005260:Female; D006801:Humans; D017495:Hyperpigmentation / Q000188:drug therapy*; D008517:Phytotherapy; D010936:Plant Extracts / Q000627:therapeutic use; D016896:Treatment Outcome
chemical_list: D000975:Antioxidants; D010936:Plant Extracts