ATN-161 as an Integrin α5β1 Antagonist Depresses Ocular Neovascularization by Promoting New Vascular Endothelial Cell Apoptosis

• Published in: Medical science monitor 2018-08, Vol.24, p.5860-5873
• Main Authors: Sui, Ailing, Zhong, Yisheng, Demetriades, Anna M, Shen, Jikui, Su, Ting, Yao, Yiyun, Gao, Yushuo, Zhu, Yanji, Shen, Xi, Xie, Bing
• Format: Article
• Language: English
• Subjects: Angiogenesis Inhibitors - pharmacology; Animals; Apoptosis - drug effects; Cell Movement - drug effects; Cell Proliferation - drug effects; Choroidal Neovascularization - drug therapy; Choroidal Neovascularization - metabolism; Disease Models, Animal; Endothelial Cells - metabolism; Eye - pathology; Female; Integrin alpha5beta1 - antagonists & inhibitors; Intravitreal Injections; Lab/In Vitro Research; Matrix Metalloproteinase 2 - metabolism; Matrix Metalloproteinase 9 - metabolism; Mice; Mice, Inbred C57BL; NF-kappa B - metabolism; Oligopeptides - pharmacology; Retinal Neovascularization - drug therapy; Retinal Neovascularization - metabolism
• ISSN: 1643-3750; 1234-1010; 1643-3750
• DOI: 10.12659/MSM.907446

BACKGROUND ATN-161 (Ac-PHSCN-NH2), an antagonist of integrin α5β1, has shown an important influence in inhibiting tumor angiogenesis and metastasis of other tumor types. However, the mechanism of action of ATN-161 and whether it can inhibit ocular neovascularization (NV) are unclear. This study investigated the role of ATN-161 in regulating ocular angiogenesis in mouse models and explored the underlying signaling pathway. MATERIAL AND METHODS An oxygen-induced retinopathy (OIR) mouse model and a laser-induced choroidal neovascularization (CNV) mouse model were used to test integrin a5b1 expression and the effect of ATN-161 on ocular NV by immunofluorescence staining, Western blot analysis, and flat-mount analysis. The activation of nuclear factor-κB (NF-κB), matrix metalloproteinase-2/9 (MMP-2/9), and cell apoptosis were detected by immunofluorescence staining, Western blot, real-time RT-PCR, and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL). The cell proliferation was detected by BrdU labeling. RESULTS In OIR and CNV mice, the protein expression level of integrin α5β1 increased compared with that in age-matched controls. The mice given ATN-161 had significantly reduced retinal neovascularization (RNV) and CNV. Blocking integrin a5b1 by ATN-161 strongly inhibited nuclear factor-κB (NF-κB) activation and matrix metalloproteinase-2/9 (MMP-2/9) expression and promoted cell apoptosis, but the effect of ATN-161 on proliferation in CNV mice was indirect and required the inhibition of neovascularization. Inhibiting NF-κB activation by ammonium pyrrolidinedithiocarbamate (PDTC) reduced RNV and promoted cell apoptosis in ocular NV. CONCLUSIONS Blocking integrin α5β1 by ATN-161 reduced ocular NV by inhibiting MMP-2/MMP-9 expression and promoting the cell apoptosis of ocular NV.