title: Cell viability effects of triamcinolone acetonide and preservative vehicle formulations.
abstract: OBJECTIVE
  To assess the effect of triamcinolone acetonide and preservative vehicle formulations on human retinal pigment epithelium (ARPE19) cells over a range of concentrations.
  
  
  METHODS
  Triamcinolone acetonide, in its trade and preservative free formulations, along with the preservative vehicle were added to ARPE19 cell cultures in various concentrations (0.01-1.0 mg/ml). Cell viability was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay at day 5 after exposure. Functionality of the cultured ARPE19 cell line was confirmed by exposure to a previously characterised toxic agent, tamoxifen.
  
  
  RESULTS
  The ARPE19 cell line behaved as predicted with exposure to tamoxifen. All formulations caused significant reductions in ARPE19 cell viability at the highest concentrations (1.0 mg/ml for triamcinolone preparations and undiluted vehicle). Cell viability was reduced to the greatest degree in trade formulation triamcinolone, less so by the vehicle, and least by preservative free triamcinolone. At lower concentrations no significant effect on cell viability was observed, although cell viability was found to be inversely proportional to increasing concentration of all tested reagents
  
  
  CONCLUSIONS
  Both the trade and preservative free formulations of triamcinolone acetonide as well as the vehicle result in cell loss at in vitro concentrations of 1 mg/ml. Although this represents theoretical vitreous concentrations achieved with current widespread therapeutic use it probably does not indicate the actual exposure of cells in their biological milieu. That cell viability was reduced most in the trade formulation suggests a possible potentiated inhibitory toxic effect of triamcinolone acetonide and vehicle at higher concentrations.
authors.affiliation: 44 Lake Beauty Drive Suite 300, Orlando, FL 32806, USA. saads@earthlink.net
authors.forename: S
authors.initials: S
authors.lastname: Shaikh
authors.forename: S
authors.initials: S
authors.lastname: Ho
authors.forename: L A
authors.initials: LA
authors.lastname: Engelmann
authors.forename: S W
authors.initials: SW
authors.lastname: Klemann
mesh_terms: D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D018931:Antineoplastic Agents, Hormonal / Q000494:pharmacology; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D003470:Culture Media; D006801:Humans; D008858:Microscopy, Phase-Contrast / Q000379:methods; D014677:Pharmaceutical Vehicles; D010857:Pigment Epithelium of Eye / Q000166:cytology / Q000187:drug effects*; D011310:Preservatives, Pharmaceutical / Q000494:pharmacology*; D012160:Retina / Q000166:cytology / Q000187:drug effects; D013629:Tamoxifen / Q000494:pharmacology; D014222:Triamcinolone Acetonide / Q000494:pharmacology*
chemical_list: D000893:Anti-Inflammatory Agents; D018931:Antineoplastic Agents, Hormonal; D003470:Culture Media; D014677:Pharmaceutical Vehicles; D011310:Preservatives, Pharmaceutical; D013629:Tamoxifen; D014222:Triamcinolone Acetonide