title: Effect of fluoroquinolones on melanogenesis in normal human melanocytes HEMn-DP: a comparative in vitro study.
abstract: OBJECTIVE
  Fluoroquinolones are one of the most commonly prescribed classes of antibiotics. However, their use is often connected with high risk of phototoxic reactions that lead to various skin or eye disorders. The aim of this study was to examine the effect of ciprofloxacin, lomefloxacin, moxifloxacin and fluoroquinolone derivatives with different phototoxic potential, on the viability and melanogenesis in melanocytes.
  
  
  METHODS
  Normal human epidermal melanocytes, dark pigmented (HEMn-DP) were used as an in vitro model system. The effect of the tested antibiotics on cell viability and melanization in pigmented cells was investigated using a spectrophotometric method. The WST-1 assay was used to detect the cytotoxic effect of antibiotics.
  
  
  RESULTS
  Ciprofloxacin, lomefloxacin and moxifloxacin induced the concentration-dependent loss in melanocytes viability. The values of EC50for the tested fluoroquinolone derivatives were found to be 2.0 mM for ciprofloxacin, 0.51 mM for lomefloxacin and 0.27 mM for moxifloxacin. The exposure of cells to different concentrations of the analyzed drugs resulted in decrease in melanin content and tyrosinase activity. The highest decrease was observed for lomefloxacin which may explain its high phototoxic potential in vivo. The role of melanin in the mechanism of the toxicity of fluoroquinolones was discussed and the obtained results were compared with the previously obtained data concerning light-pigmented melanocytes (HEMa-LP).
  
  
  CONCLUSIONS
  The results obtained in vitro suggest that the phototoxic potential of fluoroquinolones in vivo depends on specific drug-melanin interaction, the ability of drugs to affect melanogenesis as well as on the degree of melanocytes pigmentation.
authors: a Department of Pharmaceutical Chemistry , Medical University of Silesia in Katowice , Sosnowiec , Poland.
authors: Artur
authors: A
authors: Beberok
authors: a Department of Pharmaceutical Chemistry , Medical University of Silesia in Katowice , Sosnowiec , Poland.
authors: Dorota
authors: D
authors: Wrześniok
authors: a Department of Pharmaceutical Chemistry , Medical University of Silesia in Katowice , Sosnowiec , Poland.
authors: Zuzanna
authors: Z
authors: Rzepka
authors: a Department of Pharmaceutical Chemistry , Medical University of Silesia in Katowice , Sosnowiec , Poland.
authors: Jakub
authors: J
authors: Rok
authors: a Department of Pharmaceutical Chemistry , Medical University of Silesia in Katowice , Sosnowiec , Poland.
authors: Marcin
authors: M
authors: Delijewski
authors: a Department of Pharmaceutical Chemistry , Medical University of Silesia in Katowice , Sosnowiec , Poland.
authors: Michał
authors: M
authors: Otręba
authors: a Department of Pharmaceutical Chemistry , Medical University of Silesia in Katowice , Sosnowiec , Poland.
authors: Michalina
authors: M
authors: Respondek
authors: a Department of Pharmaceutical Chemistry , Medical University of Silesia in Katowice , Sosnowiec , Poland.
authors: Ewa
authors: E
authors: Buszman
mesh_terms: D000900:Anti-Bacterial Agents / Q000633:toxicity*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D002939:Ciprofloxacin / Q000633:toxicity; D017484:Dermatitis, Phototoxic / Q000209:etiology*; D000078404:Epidermal Cells; D004817:Epidermis / Q000187:drug effects; D024841:Fluoroquinolones / Q000633:toxicity*; D006801:Humans; D008543:Melanins / Q000096:biosynthesis*; D008544:Melanocytes / Q000187:drug effects* / Q000201:enzymology; D014442:Monophenol Monooxygenase / Q000378:metabolism; D000077266:Moxifloxacin; D013053:Spectrophotometry
chemical_list: D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D008543:Melanins; D002939:Ciprofloxacin; D014442:Monophenol Monooxygenase; C053091:lomefloxacin; D000077266:Moxifloxacin
keywords: Fluoroquinolones; melanin; melanocytes; tyrosinase activity