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Differentiation, Maintenance, and Analysis of Human Retinal Pigment Epithelium Cells: A Disease-in-a-dish Model for BEST1 Mutations
Published on: August 24, 2018
Signaling pathways involved in PDGF-evoked cellular responses in human RPE cells
Margrit Hollborn1, Andreas Bringmann, Frank Faude
1Department of Ophthalmology and Eye Clinic, University of Leipzig Medical Faculty, 04103 Leipzig, Germany. hollbm@medizin.uni-leipzig.de
Biochemical and Biophysical Research Communications
|April 25, 2006
Summary
Platelet-derived growth factor (PDGF) stimulates vascular endothelial growth factor-A (VEGF-A) production in retinal pigment epithelial cells. This process involves multiple signaling pathways regulating cell growth and migration.
Area of Science:
- Ophthalmology
- Cell Biology
- Molecular Biology
Background:
- Retinal pigment epithelial (RPE) cells play a crucial role in retinal health.
- Vascular Endothelial Growth Factor (VEGF) is a key regulator of angiogenesis and vascular permeability.
- Platelet-Derived Growth Factor (PDGF) is implicated in various cellular processes, including proliferation and migration.
Purpose of the Study:
- To investigate if PDGF directly stimulates VEGF-A expression in RPE cells.
- To explore the involvement of three key signal transduction pathways (ERK1/2, p38, Akt) in PDGF-mediated RPE cell responses.
- To determine the role of these pathways in PDGF-induced RPE cell proliferation, migration, and VEGF-A production.
Main Methods:
- In vitro study using RPE cells.
- Analysis of VEGF-A gene and protein expression.
- Assessment of cell proliferation and chemotaxis.
- Measurement of signaling pathway activation via protein phosphorylation (ERK1/2, p38, Akt).
- Investigation of mRNA expression for VEGF family members and receptors.
Main Results:
- PDGF significantly increased VEGF-A gene and protein expression in RPE cells.
- PDGF enhanced RPE cell proliferation and chemotaxis.
- PDGF activated ERK1/2, p38, and Akt signaling pathways.
- ERK1/2, p38, and Akt pathways were involved in PDGF-evoked proliferation.
- p38 and PI3K (Akt) pathways mediated PDGF-induced cell migration.
- PI3K (Akt) pathway mediated PDGF-induced VEGF-A secretion.
- RPE cells also expressed other VEGF family members and receptors (VEGF-B, -C, -D, flt-1, KDR).
Conclusions:
- PDGF selectively stimulates VEGF-A expression in RPE cells.
- PDGF utilizes at least three distinct signal transduction pathways to regulate RPE cell functions.
- These pathways are differentially involved in mediating RPE cell proliferation, migration, and VEGF-A production.
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