Abstract
Purpose: Inhibition of VEGF in the eye is an important treatment modality for reducing proliferation and migration of retinal pigment epithelium (RPE) in age-related macular degeneration (AMD). Additionally, previous studies suggest calcium-independent phospholipase A2 group VIA (iPLA2-VIA) to be a potential regulator of cell proliferation and migration, and evidence show abundant expression of iPLA2-VIA in RPE cells. The aim of the present study was to evaluate the potential role of iPLA2-VIA in VEGF-induced proliferation and migration of RPE cells.
Materials and methods: The human RPE cell line, ARPE-19, was used in all assays. To explore the role of iPLA2-VIA in VEGF-induced RPE proliferation and migration, iPLA2-VIA inhibition by the iPLA2-VIA specific inhibitor, bromoenol lactone, was done. RPE cell proliferation and migration were evaluated by measurements of incorporated radioactive thymidine in DNA and by a Boyden chamber technique, respectively. A luciferase assay monitored the VEGF-induced iPLA2-VIA transcriptional activity. Western blot analysis and an activity assay were used to detect the protein levels and activity of iPLA2-VIA respectively after treatment with VEGF.
Results: RPE cells treated with VEGF showed significant increased proliferation and migration. Furthermore, inhibition of iPLA2-VIA significantly reduced the spontaneous proliferation and migration as well as the VEGF-induced proliferation and migration. Finally, inhibition of iPLA2-VIA reduced the VEGF-induced iPLA2-VIA-activity, -protein level, and -promoter activity.
Conclusions: A significant interaction between VEGF and iPLA2-VIA in the regulation of RPE cells appears to be relevant in elucidating the exact mechanisms of action in the proliferative and migratory phenotype of RPE cells in AMD.
Materials and methods: The human RPE cell line, ARPE-19, was used in all assays. To explore the role of iPLA2-VIA in VEGF-induced RPE proliferation and migration, iPLA2-VIA inhibition by the iPLA2-VIA specific inhibitor, bromoenol lactone, was done. RPE cell proliferation and migration were evaluated by measurements of incorporated radioactive thymidine in DNA and by a Boyden chamber technique, respectively. A luciferase assay monitored the VEGF-induced iPLA2-VIA transcriptional activity. Western blot analysis and an activity assay were used to detect the protein levels and activity of iPLA2-VIA respectively after treatment with VEGF.
Results: RPE cells treated with VEGF showed significant increased proliferation and migration. Furthermore, inhibition of iPLA2-VIA significantly reduced the spontaneous proliferation and migration as well as the VEGF-induced proliferation and migration. Finally, inhibition of iPLA2-VIA reduced the VEGF-induced iPLA2-VIA-activity, -protein level, and -promoter activity.
Conclusions: A significant interaction between VEGF and iPLA2-VIA in the regulation of RPE cells appears to be relevant in elucidating the exact mechanisms of action in the proliferative and migratory phenotype of RPE cells in AMD.
| Originalsprog | Udefineret/Ukendt |
|---|---|
| Tidsskrift | Current Eye Research |
| Vol/bind | 37 |
| Udgave nummer | 6 |
| Sider (fra-til) | 500-507 |
| Antal sider | 8 |
| ISSN | 0271-3683 |
| DOI | |
| Status | Udgivet - 1 jun. 2012 |