Abstract:AIM:To investigate the role of cellular autophagy in the expression of IL-1β and IL-6 by retinal pigment epithelium(RPE)cells under hypoxia.
METHODS: A cultured human RPE cell line was randomly divided into the hypoxia group, 3-methyladenine(3-MA)+ hypoxia group, chloroquine(CQ)+ hypoxia group and the control group. Cells incubated in a hypoxic incubator were set as the hypoxia group. After culture for 24h, western blot was used to analyze the relative expression of autophagy-associated key proteins in each group, including microtubule associated protein 1 light chain 3B(LC3B), Beclin-1 and p62. Then, ELISA was applied to detect the concentration of IL-1β and IL-6 in the cell culture supernatants.
RESULTS: The concentration of IL-1β and IL-6 in the hypoxia group was significantly higher than that in the control group 3-MA+hypoxia group and CQ+ hypoxia group(all P<0.01). The relative expression of LC3B-II/I and Beclin-1 in the hypoxia group was significantly higher than that in the control group and 3-MA+hypoxia group. The relative expression of LC3B-II/I in the hypoxia group was significantly lower than that in the CQ+ hypoxia group(all P<0.01). The relative expression of p62 in the hypoxia group was significantly lower than that in the control group, 3-MA+hypoxia group and CQ+ hypoxia group(all P<0.01).
CONCLUSION: Hypoxia can enhance the expression of LC3B-II/I and Beclin-1 in RPE cells, weaken the expression of p62, and promote the secretion of IL-1β and IL-6. Autophagy inhibitors 3-MA and CQ can reduce the expression of IL-1βand IL-6 in RPE cells.