Angiogenic factor with G patch and FHA domains 1 protects retinal vascular endothelial cells under hyperoxia by inhibiting autophagy

Abstract

Angiogenic factor with G patch and FHA domains 1 (AGGF1) has strong proangiogenic effects on embryonic vascular development and angiogenesis in disease; however, its role in retinopathy has not been elucidated. Retinopathy of prematurity is a serious retinal disorder of premature infants, which is caused by the arrest of immature retinal vascular growth under hyperoxia. This study aims to investigate the effects of AGGF1 on retinal vascular endothelial cells under hyperoxia and the association with autophagy by using rhesus macaque choroid‐retinal endothelial (RF/6A) cells. Western blot analysis and immunofluorescence staining were used to detect the expression of AGGF1 in RF/6A cells. Cell Counting Kit‐8, flow cytometry, and transwell and matrigel assays were applied to detect the vitality, apoptosis, migration, and tube formation of RF/6A cells, respectively. Western blot analysis was then used to detect the expression of autophagy markers LC3 and Beclin‐1, and mCherry‐GFP‐LC3 adenovirus was used to detect autophagy flux in RF/6A cells. Under hyperoxia, the expression of AGGF1 in RF/6A cells decreased compared with the control. Cell vitality, migration, and tube formation decreased, and apoptosis of RF/6A cells increased under hyperoxia, and these effects of hyperoxia were attenuated by AGGF1. The protein expressions of LC3 and Beclin‐1 increased in RF/6A cells and autophagy flux enhanced under hyperoxia. AGGF1 reduced the expression of LC3 and Beclin‐1 as well as the autophagy flux stimulated by hyperoxia. The results clearly showed that exogenous AGGF1 can protect retinal vascular endothelial cells and promote angiogenesis under hyperoxia, in which the expression of AGGF1 was inhibited. Inhibition of autophagy by AGGF1 may be one of the mechanisms involved.

Protective Effect of Fenofibrate on Oxidative Stress-Induced Apoptosis in Retinal–Choroidal Vascular Endothelial Cells: Implication for Diabetic Retinopathy Treatment

“…Therefore, we used PQ as the inducer of oxidative stress to simulate the condition in DR. We used retinal/choroidal vascular endothelial cell (RF/6A) cells as the cell model system. RF/6A cell line is a monkey choroidal–retinal vascular endothelial cell line and has been widely used to study retinal vascular diseases and DR previously [ 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 ]. The study was performed in two parts.…”

Protective Effect and Mechanism of Autophagy in Endothelial Cell Injury Induced by Hyperoxia

“…12 In retinal angiogenesis studies, hyperoxia induces increased autophagy, while inhibition of autophagy promotes angiogenesis. 13 These studies suggest that autophagy may be closely related to angiogenesis under stress. In a recent study, hyperoxia impairs mitochondrial function and autophagy in pulmonary microvascular endothelial cells.…”