title: The effects of vital dyes on retinal pigment epithelium cells in oxidative stress.
abstract: OBJECTIVE
  To determine the effect of the most commonly used vital dyes in vitrectomy [trypan blue at 0.15% concentration and indocyanine green (ICG) at 0.5% concentration] on the viability of human retinal pigment epithelium (RPE) cell lines (ARPE-19) exposed to oxidative stress.
  
  
  METHODS
  ARPE-19 cells unexposed or exposed to oxidative stress (hypoxic chamber) were treated for 1 min with one of the dyes. RPE proliferation was measured by (3)H-thymidine incorporation, adhesion by ability to adhere to fibronectin, and safety by annexin V staining.
  
  
  RESULTS
  Proliferation: The dyes affected the proliferation of RPE cells differently under non-hypoxic and hypoxic conditions (p = 0.001). In non-hypoxic conditions, there was no statistically significant difference between the proliferation of the treated (both dyes) and untreated RPE cells (p = 0.279). Under hypoxia, both dyes significantly suppressed proliferation, more so with ICG (p = 0.001). Adhesion: The dyes affected adhesion differently under non-hypoxic and hypoxic conditions (p = 0.04). In non-hypoxic conditions, both increased the adhesive properties of RPE cells to fibronectin, ICG more than trypan blue (p = 0.001). Under hypoxia, both dyes suppressed adhesion, with no statistically significant difference between treated and non-treated RPE cells. Apoptosis: Both dyes increased early apoptosis of RPE cells compared with no treatment (p = 0.001), ICG more than trypan blue. Hypoxia increased the apoptosis of both dyes compared to non-hypoxic conditions (p = 0.02).
  
  
  CONCLUSIONS
  In hypoxic conditions, both dyes showed an inhibition of RPE adhesion to fibronectin and proliferation capacity and an increase in early apoptosis compared with non-hypoxic conditions. Apoptosis was greater in ICG-treated RPE cells than in trypan blue-treated cells.
authors.affiliation: Department of Ophthalmology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.
authors.forename: Shani
authors.initials: S
authors.lastname: Golan
authors.forename: Ran
authors.initials: R
authors.lastname: Levi
authors.forename: Michal
authors.initials: M
authors.lastname: Entin-Meer
authors.forename: Adiel
authors.initials: A
authors.lastname: Barak
mesh_terms: D017304:Annexin A5 / Q000378:metabolism; D017209:Apoptosis; D002448:Cell Adhesion / Q000187:drug effects; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D004396:Coloring Agents / Q000633:toxicity*; D005353:Fibronectins / Q000378:metabolism; D006801:Humans; D007208:Indocyanine Green / Q000633:toxicity*; D018384:Oxidative Stress; D055213:Retinal Pigment Epithelium / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D014343:Trypan Blue / Q000633:toxicity*
chemical_list: D017304:Annexin A5; D004396:Coloring Agents; D005353:Fibronectins; D014343:Trypan Blue; D007208:Indocyanine Green