Abstract
Purpose: :
Latanoprost and bimatoprost are PGF2 analogues that increase aqueous humor outflow through both the uveoscleral and trabecular meshwork pathways. Latanoprost and PGF2 exert their effect on trabecular meshwork cells mainly through prostaglandin FP receptors while bimatoprost is thought to use a prostamide receptor. Since all three molecules lower intraocular pressure, we hypothesized that common cellular processes are affected. In this study, we identified common, differentially expressed gene sequences between latanoprost, bimatoprost and PGF2 treated primary human trabecular meshwork cells.
Methods: :
Three confluent primary human trabecular meshwork cell lines were incubated with DMEM containing latanoprost-free acid (LFA; 100nM), bimatoprost-free acid (BFA; 1 µM), or PGF2 (100nM). DMEM containing vehicle was used as the control. Following 2, 6, 12, 24, and 72-hour incubations, total RNA was isolated from each cell line and processed into cRNA. A total of 90 Affymetrix GeneChip Human Genome U133 Plus 2.0 arrays were probed. Following normalization, differentially regulated gene sequences that had a 1.25 fold change in gene expression (up- or down regulated) in all three cell lines were considered significant. Real-time PCR was used to verify the accuracy of the microarrays. Differentially regulated sequences were analyzed using Metacore (Genego, Inc) and Ingenuity Pathway Analysis (Redwood City, CA) software programs.
Results: :
Comparison of differentially expressed genes at all time points identified 294 sequences that were common between LFA, BFA, and PGF2 treatments. 37 of the 294 sequences were differentially expressed at multiple time points. Within 12 hours of treatment, the majority of differentially expressed sequences were associated with cellular processes involving transcriptional regulation and signaling pathway progression (i.e. NEDD9, CITED2, IL6, RTKN). After 12 hours of treatment, several cytokines, growth factors, and genes associated with integrin signaling and cell adhesion showed differential gene expression (i.e. IL8,TGFβ2, ITGA8, PKP4).
Keywords: trabecular meshwork • gene/expression • drug toxicity/drug effects