title: Inhibitory effect of liposome-encapsulated anthocyanin on melanogenesis in human melanocytes.
abstract: BACKGROUND
  Melanin plays an important role in preventing ultraviolet (UV) light-induced skin damage. Overexposure to UV radiation can lead to the formation of free radicals and trigger inflammation and hyperpigmentation of the skin. Anthocyanin can combat excessive free radicals in the body and can reduce the occurrence of inflammation. However, anthocyanin molecules are unstable and highly susceptible to degradation.
  
  
  OBJECTIVE
  The present study aims to elucidate the effects of liposome-capsulated anthocyanin (LCA) from Hibiscus sabdariffa Linn. on melanogenesis in human A375 melanocytes.
  
  
  METHODS
  The effects of LCA with various doses (5-50 mg/mL) on cell viability, melanin content, tyrosinase activity, expression of the tyrosinase and microphthalmia-associated transcription factor (MITF) were measured.
  
  
  RESULTS
  Anthocyanin exhibits scavenging activity on DPPH radical with the inhibitory rate of 11 and 24% at 20 and 50 mg/mL concentration treatment, respectively, and inhibitory effects on melanin production by 8, 14, 23 and 30% at 5, 10, 20 and 50 mg/mL concentration treatment, respectively. However, LCA has enhanced DPPH scavenging activity (64 and 76% at 20 and 50 mg/mL concentration treatment, respectively) and inhibitory effects against melanin synthesis (23, 35, 43 and 60% at 5, 10, 20 and 50 mg/mL concentration treatment, respectively). Moreover, anthocyanin-inhibited melanin synthesis occurs through the inhibition of tyrosinase enzymatic activity and suppression of the protein expression of tyrosinase and MITF.
  
  
  CONCLUSIONS
  Liposome encapsulation increases the stabilization of anthocyanin and the inhibition of melanogenesis. Our findings indicate that LCA may be suitable as a photoprotective agent for the skin.
authors.affiliation: School of Applied Chemistry, Chung Shan Medical University, Taichung, Taiwan.
authors.forename: Jin-Ming
authors.initials: JM
authors.lastname: Hwang
authors.forename: Hsing-Chun
authors.initials: HC
authors.lastname: Kuo
authors.forename: Ching-Ting
authors.initials: CT
authors.lastname: Lin
authors.forename: Erl-Shyh
authors.initials: ES
authors.lastname: Kao
mesh_terms: D000872:Anthocyanins / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004355:Drug Stability; D016166:Free Radical Scavengers / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology; D031584:Hibiscus / Q000737:chemistry*; D006801:Humans; D008081:Liposomes; D008543:Melanins / Q000096:biosynthesis*; D008544:Melanocytes / Q000187:drug effects* / Q000378:metabolism; D008545:Melanoma / Q000378:metabolism; D051739:Microphthalmia-Associated Transcription Factor / Q000235:genetics; D014442:Monophenol Monooxygenase / Q000235:genetics / Q000378:metabolism
chemical_list: D000872:Anthocyanins; D016166:Free Radical Scavengers; D008081:Liposomes; D008543:Melanins; D051739:Microphthalmia-Associated Transcription Factor; D014442:Monophenol Monooxygenase