Autophagy: a new mechanism for regulating VEGF and PEDF expression in retinal pigment epithelium cells

• 作者: Guo-Min Yao Jin Zhang Jun-Hui Du Rong Li Yang Yao
• 来源期刊: 国际眼科杂志:英文版
• 学科: 医学
• 关键词: AUTOPHAGY RETINAL PIGMENT EPITHELIUM CELLS vascular endothelial growth factors PIGMENT epithelium-derived factor angiogenesis
• 年，卷（期）: gjykzzywb_2019,（4）
• 页码范围: 557-562
• 页数: 6页
• 分类号: R

摘要

AIM: To investigate the regulation of vascular endothelial growth factors (VEGF) and pigment epithelium-derived factor (PEDF) expression by autophagy in retinal pigment epithelium (RPE) cells on exposure to hypoxia. METHODS: ARPE-19, an RPE cell line, was treated as following: the control group was kept in a normoxic incubator;the hypoxia group was incubated in a hypoxic incubator with 1% O2/5% CO2/94% N2 for 24h;the hypoxia + 3-methyladenine (3-MA) group was pretreated with 10 mmol/L 3-MA for 1h and then in the hypoxic incubator for 24h;and the hypoxia + chloroquine (CQ) group was pretreated with 50 μmol/L CQ for 1h and then in the hypoxic incubator for 24h. The morphology and ultrastructure of the cells was observed by an inverted microscope or a transmission electronic microscope (TEM). Western blot was performed to assay the expression of autophagy-associated markers, including microtubule associated protein 1 light chain 3 B (LC3B), Beclin-1, Atg5 and p62. The concentration of VEGF and PEDF in the culture supernatant was determined by ELISA, and the ratio of VEGF/PEDF was calculated. RESULTS: There were no obvious differences in cell morphology among different groups and autolysosomes could be observed in the cytoplasm in all groups. Compared to the control cells, the LC3B-II/I ratio and levels of Beclin-1 and Atg5 were significantly increased and p62 level was significantly decreased in the hypoxia group. With the increase of VEGF and decrease of PEDF concentration, the VEGF/PEDF ratio was significantly increased in the hypoxia group compared to the control cells. The LC3B-II/I ratio was significantly reduced by 3-MA treatment and increased by CQ treatment. The expressions of Beclin-1 and Atg5 were significantly reduced by 3-MA or CQ treatment, while expression of p62 was increased in the 3-MA or CQ treated cells. The concentration of VEGF was significantly decreased and PEDF increased, thereby the VEGF/PEDF ratio was decreased in the hypoxia + 3-MA group and hypoxia + CQ group compared with that in the hy