Abstract
Purpose: :
Age-related macular degeneration (AMD) is the leading cause of legal blindness in developed countries. Late AMD is the most severe variety of this disease and choroidal neovascularization (CNV) is the first cause of central vision lost. The aim of this study was to inhibit the progression of CNV with two different TGF-beta 1 inhibitor peptides.
Methods: :
The animal model is based on the CNV laser induction in Long-Evans rats. We had six groups: control, four groups that received intravitreally two different doses of P17 (1 µg/µl and 20 µg/µl) and P144 (1 µg/µl and 3 µg/µl) 48 hours after laser induction; and one group received that 5 doses of P17 intravenously (200 µl) every 72 hours. Monitoring of CNV evolution was assessed once a week through colour retinography and fluorescein angiography (FA) during 4 weeks, and results were statistically analyzed with SPSS 13.0 software
Results: :
A significant decrease (P<0.05) of CNV percentage in rat retinas intravenously treated with P17 were found since the first week with highest differences at the second week (p=7.7 x 10-6). Animals treated with P17 intravitreally only developed a significant reduction of CNV at the highest doses during the last two weeks. Moreover results show a significant decrease (P<0.05) of CNV percentage in retinas treated with both doses of p144 (1 µg/ 3 µg) in every monitored time point. Highest differences were found at the first week with both doses.
Conclusions: :
The obtained results show a very significant inhibition of P17 on CNV only at high or repeated doses that counteract the fast metabolic elimination of this peptide. About P144, results obtained show a very significant and long-term effect on CNV related with its progressive solubility in physiologic solutions.
Keywords: choroid: neovascularization • growth factors/growth factor receptors • laser