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Abstract #20740 Published in IGR 10-1
Activation of TGF-β1 Through Up-Regulation of TSP-1 by Retinoic Acid in Retinal Pigment Epithelial Cells
Uchida H; Shitama T; Hayashi H; Kuroki MCurrent Eye Research 2008; 33: 199-203
PURPOSE: Retinoic acid (RA) affects the activation of transforming growth factor-β 1 (TGF-β 1) in a variety of cells. We have previously shown that thrombospondin-1 (TSP-1) expression in retinal pigment epithelial (RPE) cells is up-regulated by RA. Since TSP-1 activates TGF-β 1, we investigated whether RA stimulates the activation of TGF-β 1 through up-regulation of TSP-1 in RPE cells. METHODS: Human RPE cells were cultured with RA or TSP-1. The active form of TGF-β 1 in the culture medium was measured by enzyme-linked immunosorbent assay. RESULTS: The active form of TGF-β 1 was increased dose-dependently by RA or TSP-1. The activation of TGF-β 1 by RA was significantly hampered by an anti-TSP-1 antibody. Also, antibodies against integrins α vβ 3 and α vβ 5 inhibited the activation of TGF-β 1.CONCLUSIONS: These findings suggest that, in RPE cells, RA increases the activation of TGF-β 1 via up-regulation of TSP-1, and integrins such as α vβ 3 and α vβ 5 are essential in this activation step.
Dr. H. Uchida, Department of Ophthalmology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
Classification:
2.13 Retina and retinal nerve fibre layer (Part of: 2 Anatomical structures in glaucoma)
3.7 Biochemistry (Part of: 3 Laboratory methods)
3.8 Pharmacology (Part of: 3 Laboratory methods)