Carboxyamido-triazole modulates retinal pigment epithelial and choroidal endothelial cell attachment, migration, proliferation, and MMP-2 secretion of choroidal endothelial cells.

PURPOSE: To determine the effect of the calcium signaling modulating drug carboxyamido-triazole (CAI) on substeps of exudative age-related macular degeneration (AMD) in vitro. MATERIALS AND METHODS: Zymography and ELISA determined the effect of CAI on MMP-2 production of choroidal endothelial cells (CECs) stimulated by bFGF and VEGF. The effects of CAI on attachment of retinal pigment endothelial (RPE) cells/CECs onto fibronectin, laminin, collagen IV, and migration toward fibronectin were investigated. Proliferation induced by serum and bFGF (10 microg/ml) with and without CAI (0.1-10 microM) was measured by cell counting and 3H-uptake. Viability and apoptosis of the exposed cells was assessed by an MTT and an apoptosis assay. RESULTS: CAI inhibited serum- and bFGF-induced proliferation, cell attachment onto fibronectin and collagen IV, but only CEC attachment onto laminin. Inhibition of MMP-2 production was observed (10 microM CAI). CAI reduced the cellular viability by apoptosis induction. CONCLUSIONS: CAI inhibits substeps of exudative macular degeneration and may be of value for the treatment of the disease.

A role for connective tissue growth factor in the pathogenesis of choroidal neovascularization.

OBJECTIVE: To evaluate the expression of connective tissue growth factor (CTGF) in choroidal neovascular membranes from patients with age-related macular degeneration and the effect of CTGF on choroidal endothelial cell (CEC) function. METHODS: Using immunohistochemical methods, we analyzed CTGF expression in 13 surgically excised choroidal neovascular membranes related to age-related macular degeneration. The expression of CTGF in retinal pigment epithelial and CEC cultures was determined by means of reverse transcriptase polymerase chain reaction and Western blot, and its regulation by vascular endothelial growth factor and transforming growth factor beta was determined. The effects of CTGF on bovine CEC proliferation, attachment, migration, and tube formation were measured. RESULTS: Vascularized human choroidal neovascular membranes showed strong CTGF immunoreactivity. Double staining disclosed colocalization of CTGF with retinal pigment epithelial cells and CECs. The CTGF induced a significant increase in attachment and migration of CECs; however, it did not stimulate CEC proliferation. The CTGF protein was up-regulated in retinal pigment epithelial cells and CECs by stimulation with transforming growth factor beta and vascular endothelial growth factor, respectively. CONCLUSIONS: The expression of CTGF in choroidal neovascular membranes, its regulation by angiogenic growth factors, and its proangiogenic effects on CEC function suggest that CTGF may play a role in the pathogenesis of choroidal neovascularization. Clinical Relevance Multiple growth factors are involved in the pathogenesis of choroidal neovascularization in age-related macular degeneration.