Design and Development of Modulators for Lysyl Oxidase to Regulate Ocular Angiogenesis

Abstract

The high prevalence of angiogenesis related diseases including ocular diseases has floodlit very high demand for more efficient and safer therapeutics. New molecular targets were investigated for achieving better control over the condition. Lysyl oxidase (LOX) is a copper dependent amine oxidase which has known to be associated with diseases involving abnormal angiogenesis. In the present study, small peptides were designed which were predicted to have the ability to modulate LOX and hence have control over abnormal angiogenesis. Peptides were designed based on different strategies and includes peptides from the N-terminal of mature LOX near the BMP-1 cleavage site, from the conserved regions among the isoforms of LOX and from the interacting partners like elastin, histone, collagen and copper binding sites in the amino acid sequence of LOX. These peptides were analyzed for their ability to modulate LOX and angiogenesis. Angiogenesis assays were done using human umbilical vein endothelial cells. The results demonstrated that the selected peptides after the initial screening showed promising effects in modulating LOX and angiogenesis. The most potent peptides were investigated with human retinal endothelial cells (HRECs) and bovine retinal endothelial cells (BRECs) and showed ocular angiogenesis modulating effects. These bioactive peptides were further studied under vitreous from PDR (Proliferative diabetic retinopathy) stimulated conditions in HUVECs. The effect of the peptides was also studied under conditioned medium from retinoblastoma cells Y79 stimulated conditions in HUVECs. The most interesting peptides were also investigated using in vivo CAM (Chick Chorioallantoic Membrane) assay. The results showed the peptides had promising effects. The mechanism of action of the selected peptides was observed to be their ability to regulate copper which is the cofactor of LOX. This study has led to increased understanding about the interaction of small peptides that could modulate angiogenesis.