title: Dye solutions based on lutein and zeaxanthin: in vitro and in vivo analysis of ocular toxicity profiles.
abstract: OBJECTIVE
  To study the safety profile of Lutein/Zeaxanthin(L/Z)-based natural dye solutions in in vitro and in vivo models.
  
  
  METHODS
  In vitro cytotoxicity and cellular growth experiments were carried out on ARPE-19 and human corneal epithelial (HCE) cell lines using different L/Z-based dye solutions, either alone or in association with brilliant blue (BB) or trypan blue (TB). Light and transmission electron microscopy studies were performed seven days after intravitreal injection of dye solutions in rabbits. Electroretinogram (ERG) recordings were taken at baseline and before histopathology.
  
  
  RESULTS
  In vitro cytotoxicity assays demonstrated that the different L/Z-based solutions (from 0.3 to 2%), either alone or in association with BB (0.025%) or TB (0.04%), did not significantly alter mitochondrial activity (≤15%) in the cell lines tested. In addition, in vitro cell growth was inhibited by up to 60% depending on the dye solution, and in direct proportion to the concentration assayed. There was no evidence of structural alterations in the neurosensory retina, retinal pigment epithelium (RPE), or choriocapillaris-choroidal complex. b-Wave ERG records showed no significant differences (±15.2%) in comparison with baseline.
  
  
  CONCLUSIONS
  L/Z-based dye solutions demonstrated a safe profile in in vitro and in vivo models, and may be a useful tool for staining intraocular structures.
authors.affiliation: Department of Ophthalmology and Visual Sciences, Instituto da Visão (IPEPO), Universidade Federal de São Paulo , São Paulo , Brasil .
authors.forename: Ricardo P
authors.initials: RP
authors.lastname: Casaroli-Marano
authors.forename: Diogo
authors.initials: D
authors.lastname: Sousa-Martins
authors.forename: Eva M
authors.initials: EM
authors.lastname: Martínez-Conesa
authors.forename: Emmerson
authors.initials: E
authors.lastname: Badaró
authors.forename: Renata Portella
authors.initials: RP
authors.lastname: Nunes
authors.forename: Acácio As
authors.initials: AA
authors.lastname: Lima-Filho
authors.forename: Eduardo B
authors.initials: EB
authors.lastname: Rodrigues
authors.forename: Rubens
authors.initials: R
authors.lastname: Belfort
authors.forename: Maurício
authors.initials: M
authors.lastname: Maia
mesh_terms: D000818:Animals; D001557:Benzenesulfonates / Q000633:toxicity; D002460:Cell Line; D004396:Coloring Agents / Q000633:toxicity*; D004338:Drug Combinations; D004596:Electroretinography / Q000187:drug effects; D004797:Enzyme-Linked Immunosorbent Assay; D019573:Epithelium, Corneal / Q000187:drug effects* / Q000473:pathology; D006801:Humans; D058449:Intravitreal Injections; D014975:Lutein / Q000633:toxicity*; D046529:Microscopy, Electron, Transmission; D011817:Rabbits; D012160:Retina / Q000187:drug effects* / Q000503:physiopathology / Q000648:ultrastructure; D055213:Retinal Pigment Epithelium / Q000187:drug effects* / Q000473:pathology; D014343:Trypan Blue / Q000633:toxicity; D065146:Zeaxanthins / Q000633:toxicity*
chemical_list: D001557:Benzenesulfonates; D004396:Coloring Agents; D004338:Drug Combinations; D065146:Zeaxanthins; C006796:brilliant blue; D014343:Trypan Blue; D014975:Lutein
keywords: ARPE-19; chromovitrectomy; in vitro validation assays; lutein; retinal pigment epithelium; zeaxanthin