title: Effect of adenosine on melanogenesis in b16 cells and zebrafish.
abstract: BACKGROUND
  Adenosine is a nucleoside, in which an adenine molecule is attached to a ribofuranose sugar moiety. It can be released into the microenvironment by metabolically active cells, and then fulfills a multitude of functions in regulation of cell proliferation, by activating four subtypes of G protein-coupled adenosine receptors.
  
  
  OBJECTIVE
  In this study, we investigated the effect of adenosine on melanogenesis, using B16 melanoma cells.
  
  
  METHODS
  The toxic effects of adenosine on B16 melanoma cells were assessed. To understand the mechanism of the effect of adenosine on melanogenesis in B16 cells, melanin content and tyrosinase activity were measured. Tyrosinase, tyrosinase-related protein-1, and dopachrome tautomerase were monitored by Western blotting. Finally, adenosine was applied to zebrafish embryos, and its in vivo effect on pigmentation investigated.
  
  
  RESULTS
  At a low concentration, adenosine increased melanin content and tyrosinase activity, while a high dose of adenosine resulted in inhibition of tyrosinase activity. Western blotting showed that adenosine increased tyrosinase protein levels slightly, while high-dose adenosine decreased the expression of tyrosinase. In zebrafish tests, adenosine slightly inhibited body pigmentation.
  
  
  CONCLUSIONS
  In this study, we investigated the effect of adenosine on melanogenesis, using the well-established B16 melanoma cell and zebrafish models. The results suggest that adenosine may inhibit pigmentation, through negative regulation of tyrosinase.
authors.affiliation: Department of Dermatology, Research Institute of Medical Sciences, Chungnam National University School of Medicine, Daejeon, Korea.
authors.forename: Mi Yoon
authors.initials: MY
authors.lastname: Kim
authors.affiliation: Department of Dermatology, Research Institute of Medical Sciences, Chungnam National University School of Medicine, Daejeon, Korea.
authors.forename: Hae-Eul
authors.initials: HE
authors.lastname: Lee
authors.affiliation: Department of Dermatology, Research Institute of Medical Sciences, Chungnam National University School of Medicine, Daejeon, Korea.
authors.forename: Myung
authors.initials: M
authors.lastname: Im
authors.affiliation: Department of Dermatology, Research Institute of Medical Sciences, Chungnam National University School of Medicine, Daejeon, Korea.
authors.forename: Young
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Department of Dermatology, Research Institute of Medical Sciences, Chungnam National University School of Medicine, Daejeon, Korea.
authors.forename: Chang-Deok
authors.initials: CD
authors.lastname: Kim
authors.affiliation: Department of Dermatology, Research Institute of Medical Sciences, Chungnam National University School of Medicine, Daejeon, Korea.
authors.forename: Jeung-Hoon
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Dermatology, Research Institute of Medical Sciences, Chungnam National University School of Medicine, Daejeon, Korea.
authors.forename: Young-Joon
authors.initials: YJ
authors.lastname: Seo
keywords: Adenosine; Melanocytes; Melanogenesis; Pigmentation; Zebrafish