title: Modulation of melanogenesis by aloesin: a competitive inhibitor of tyrosinase.
abstract: Aloesin, [2-acetonyl-8-beta-d-glucopyranosyl-7-hydroxy-5-methylchromone], a compound isolated from the Aloe plant, is shown in these studies to modulate melanogenesis via competitive inhibition of tyrosinase. Aloesin inhibits purified tyrosinase enzyme and specifically inhibits melanin production in vitro. Enzyme kinetics studies using normal human melanocyte cell lysates and cell-based melanin production demonstrated that aloesin is a competitive inhibitor of tyrosinase from mushroom, human and murine sources. Tyrosine hydroxylase and 3,4-dihydroxyphenylalanine (DOPA) oxidase activities of tyrosinase from normal human melanocyte cell lysates were inhibited by aloesin in a dose dependent manner. In a percutaneous absorption study a finite dose of aloesin penetrated the skin slowly and was recovered primarily in the surface wash. Aloesin shows promise as a pigmentation-altering agent for cosmetic or therapeutic applications.
authors.affiliation: Univera Pharmaceuticals Inc., Broomfield, CO 80021, USA. ken@aloecorp.com
authors.forename: Ken
authors.initials: K
authors.lastname: Jones
authors.forename: Jennifer
authors.initials: J
authors.lastname: Hughes
authors.forename: Mei
authors.initials: M
authors.lastname: Hong
authors.forename: Qi
authors.initials: Q
authors.lastname: Jia
authors.forename: Steve
authors.initials: S
authors.lastname: Orndorff
mesh_terms: D000042:Absorption / Q000187:drug effects / Q000502:physiology; D000818:Animals; D002478:Cells, Cultured; D002867:Chromones / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D000078404:Epidermal Cells; D004817:Epidermis / Q000187:drug effects* / Q000201:enzymology; D005960:Glucosides / Q000494:pharmacology*; D006801:Humans; D007700:Kinetics; D008297:Male; D008543:Melanins / Q000096:biosynthesis*; D008544:Melanocytes / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D051379:Mice; D014442:Monophenol Monooxygenase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D010859:Pigmentation Disorders / Q000188:drug therapy* / Q000201:enzymology / Q000503:physiopathology; D014446:Tyrosine 3-Monooxygenase / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D002867:Chromones; D005960:Glucosides; D008543:Melanins; D014446:Tyrosine 3-Monooxygenase; D014442:Monophenol Monooxygenase; C069868:aloesin