Effect of latanoprost on cultured porcine corneal stromal cells.
OBJECTIVE
Latanoprost reduces intraocular pressure mainly by enhancing uveoscleral outflow that may be involved in the decreased of extracellular matrixes such as collagens. However, the effect of latanoprost on corneal stromal cells is not well understood. In the current study, we investigated the changes of cultured porcine corneal stromal cells upon exposure to latanoprost.


METHODS
Porcine corneal stromal cells were acquired from primary culture and maintained in fetal bovine serum-containing medium. Cells were estimated on 3H-thymidine, 3H-leucine, 3H-uridine, 3H-proline uptakes and migration. Dead and living cells were estimated with MTT assay. The changes of type 1 collagen and fibronectin proteins were detected by means of immunofluorescent staining and Western blot assay. Intracellular free Ca2+ ([Ca2+]i) mobility was studied by spectrofluorophotometer after loading with fura-2-AM.


RESULTS
Latanoprost has remarkable effects inhibiting cultured corneal stromal cells on 3H-thymidine, 3H-leucine, 3H-uridine, 3H-proline uptakes and cellular migration. The inhibitory effects are in a dose-dependent manner at concentrations ranging from 10(- 5), 10(- 6), 10(- 7) to 10(- 8) M. The 50% inhibitory dosages (ID50) for latanoprost to corneal stromal cells, as measured by 3H-thymidine uptake, 3H-uridine uptake, 3H-leucine uptake, 3H-proline uptakes and cellular migration were 5.01 x 10(- 6) M, 2.81 x 10(- 6) M, 2.09 x 10(- 6) M, 3.89 x 10(- 7) M and 2.2 x 10(- 6) M, respectively. In the presence of latanoprost, the cellular MTT values were also decreased significantly. Immunofluorescent staining displayed that latanoprost changed type 1 collagen distribution in cultured corneal stromal cells. Western blot assay revealed that latanoprost caused cells to decrease in fibronectin protein. In Ca2+-containing buffer, latanoprost induced a significant rise in [Ca2+]i at 10(- 5) and 10(- 6) M.


CONCLUSIONS
These results indicate that latanoprost may induce the morphological and biochemical changes in cultured corneal stromal cells. Long-term use of latanoprost needs to be carefully monitored for change in corneal stroma.
Wu
Kwou-Yeung
KY
Department of Ophthalmology, Kaohsiung Medical University, Kaohsiung, Taiwan.
Wang
Hwei-Zu
HZ
Hong
Show-Jen
SJ
D000818:Animals; D001548:Benzalkonium Compounds / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D024042:Collagen Type I / Q000378:metabolism; D003319:Corneal Stroma / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D005353:Fibronectins / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D015151:Immunoblotting; D007425:Intracellular Membranes / Q000378:metabolism; D000077338:Latanoprost; D007930:Leucine / Q000493:pharmacokinetics; D011392:Proline / Q000493:pharmacokinetics; D011461:Prostaglandins F, Synthetic / Q000494:pharmacology*; D013194:Staining and Labeling; D013552:Swine; D013778:Tetrazolium Salts; D013844:Thiazoles; D013936:Thymidine / Q000493:pharmacokinetics; D014529:Uridine / Q000493:pharmacokinetics
D001548:Benzalkonium Compounds; D024042:Collagen Type I; D005353:Fibronectins; D011461:Prostaglandins F, Synthetic; D013778:Tetrazolium Salts; D013844:Thiazoles; D000077338:Latanoprost; D011392:Proline; C022616:thiazolyl blue; D007930:Leucine; D002118:Calcium; D013936:Thymidine; D014529:Uridine