title: In vitro studies of antiglaucomatous prostaglandin analogues: travoprost with and without benzalkonium chloride and preserved latanoprost.
abstract: OBJECTIVE
  With use of the Wong-Kilbourne derivative Chang conjunctival cell line, this study compared in vitro the ocular toxicity of three topical intraocular pressure (IOP)-lowering agents: travoprost 0.004% containing 0.015% benzalkonium chloride (BAK), travoprost Z 0.004%, a new formulation without BAK, and latanoprost 0.005% containing 0.02% BAK.
  
  
  METHODS
  Neutral red, Alamar blue, YOPRO-1, and annexin V/7-AAD assays were used to evaluate the effects of the IOP-lowering agents and BAK on cellular viability, membrane integrity, and apoptosis in the conjunctival cell line using microtitration fluorometric analysis and flow cytometry. All assessments were performed in a masked manner.
  
  
  RESULTS
  Assessment of cell viability and membrane integrity revealed a significant effect by latanoprost with BAK or BAK alone but no effect by travoprost Z without BAK or buffer alone (P < 0.0001). Latanoprost with BAK, travoprost with BAK, and BAK alone were cytotoxic in Chang conjunctival cells, whereas no cytotoxicity was observed in cells exposed to travoprost Z without BAK or in cells treated with buffer (P < 0.0001). No increase in apoptosis or necrosis was observed in cells treated with control or travoprost Z without BAK compared with BAK, travoprost with BAK, and latanoprost with BAK (P < 0.0001).
  
  
  CONCLUSIONS
  Latanoprost with BAK, travoprost with BAK, and BAK alone have significant cytotoxic effects on human conjunctiva-derived cells and are associated with apoptosis. These effects likely result from BAK used as a preservative. IOP-lowering agents with alternative preservatives instead of BAK will most likely have fewer ocular surface adverse effects than agents containing BAK.
authors.affiliation: Department of Ophthalmology 3, Quinze-Vingts National Ophthalmology Hospital, Paris, France. baudouin@quinzw-vingts.fr
authors.forename: Christophe
authors.initials: C
authors.lastname: Baudouin
authors.forename: Luisa
authors.initials: L
authors.lastname: Riancho
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Warnet
authors.forename: Françoise
authors.initials: F
authors.lastname: Brignole
mesh_terms: D017304:Annexin A5; D000959:Antihypertensive Agents / Q000633:toxicity*; D017209:Apoptosis / Q000187:drug effects; D001548:Benzalkonium Compounds / Q000633:toxicity*; D002460:Cell Line; D002462:Cell Membrane / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D003008:Cloprostenol / Q000031:analogs & derivatives* / Q000633:toxicity; D003228:Conjunctiva / Q000187:drug effects* / Q000473:pathology; D004359:Drug Therapy, Combination; D005434:Flow Cytometry; D005901:Glaucoma / Q000188:drug therapy; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects; D000077338:Latanoprost; D009336:Necrosis; D011310:Preservatives, Pharmaceutical / Q000633:toxicity*; D011461:Prostaglandins F, Synthetic / Q000633:toxicity*; D000069557:Travoprost
chemical_list: D017304:Annexin A5; D000959:Antihypertensive Agents; D001548:Benzalkonium Compounds; D011310:Preservatives, Pharmaceutical; D011461:Prostaglandins F, Synthetic; D003008:Cloprostenol; D000077338:Latanoprost; D000069557:Travoprost