Retracted: Effects of apelin on retinal microglial cells in a rat model of oxygen‐induced retinopathy of prematurity

Abstract

This study explores the effects of apelin on retinal microglial cells in rat models of oxygen-induced retinopathy of prematurity (ROP). Totally, 274 rats were selected for establishing oxygen-induced retinopathy (OIR) models, and 92 healthy rats for control group. OIR rats were assigned into OIR, 10 g/L apelin, 10 g/L apelin, and 10 g/L apelin groups. Immunohistochemistry was employed to determine morphology of microglial cells and cell number. CDllb, ionized calcium-binding adapter molecule 1 (IBA-1), TNF-α, and iNOS mRNA and protein expressions were identified using RT-qPCR and Western blotting, respectively. ELISA was employed to determine the levels of VEGF and glial fibrillary acidic protein (GFAP). The amoeboid microglial cells were found in the OIR and 10 g/L apelin groups, while bipolar microglial cells were found in the normal control, 10 g/L apelin and 10 g/L apelin groups. In the 1, 2, 3, and 4th week after apelin treatment, there were significantly decreased bipolar microglial cells, lower mRNA and protein expressions of CDllb, IBA-1, TNF-α and iNOS, and the levels of VEGF and GFAP in the 10 g/L apelin group than in the OIR, 10 g/L apelin and 10 g/L apelin groups. The differences between the normal control and 10 g/L apelin groups are not significant. Compared with the OIR group, the 10 g/L apelin and 10 g/L apelin groups presented decreased microglial cells and mRNA and protein expressions of CDllb, IBA-1, TNF-α, and iNOS. Appropriate concentration of apelin may reduce retinal microglial cells in a rat model of oxygen-induced ROP.

Correlation between apelin and VEGF levels in retinopathy of prematurity: a matched case–control study

“…Concurrently, animal studies on retinal endothelial cell lines have demonstrated that apelin-13 has angiogenic activity [18,19]. Many animal studies and a small number of human studies have demonstrated that apelin-13 is associated with the occurrence of ROP [7][8][9]. Thus, systemic apelin-13 and VEGF may be meaningful biomarkers to aid in the diagnosis of ROP [9,20].…”

“…All bioactivity is thought to be in the terminal 13 aa fragment (apelin 13) [6]. In recent years, oxygen-induced neonatal retinopathy mouse experiments have suggested that the expression of apelin-13 can affect vascular density and morphology [7,8]. Furthermore, it may play an important role in pathological retinal neovascularisation and affect the occurrence and development of ROP.…”

G-protein coupled estrogen receptor activation protects the viability of hyperoxia-treated primary murine retinal microglia by reducing ER stress

“…The retinal microglia influence vascular branching density and endothelial cell proliferation [ 21 , 22 ]. They are also implicated in the pathology of diabetic retinopathy and OIR [ 23 , 24 ]. In this study, we investigated the protective effects of GPER activation on hyperoxia-treated primary murine retinal microglia.…”