Expression of microRNA-646 in A549 cells treated by lipopolysaccharide and its function / 中华实用儿科临床杂志

ABSTRACT

Objective To measure the expression of microRNA-646 (miR-646) in A549 cells under different concentrations of lipopolysaccharide(LPS) treatment,and to explore the possible mechanism of miR-646 in A549 cells under LPS treatment.Methods A549 cells were divided into control group and experimental groups.A549 cells from the control group were treated with RPMI-1640 and A549 cells from the experimental groups were treated with LPS (5 mg/L,10 mg/L,15 mg/L) in a duration of 24 hours.Immunocytochemical method and Western blot were used to detect the changes in surfactant protein A (SP-A) and surfactant protein C (SP-C),and quantitative real-time polymerase chain reaction was used to detect the changes in miR-646 in all groups.Results Compared with control group,the expression of SP-A in cytoplasm of A549 cells were decreased in experimental groups (all P ＜ 0.05),and LPS in different concentrations induced the expression of SP-A in A549 cells in a dose-dependent manner.Compared with control group,the expression of SP-C in cytoplasm of A549 cells was decreased in experimental groups (all P ＜ 0.05).The expression of SP-C was the lowest in 10 mg/L LPS treatment group.The relative expression level of the control group of miR-646 was 0.9597 ±0.0200,in 5 mg/L LPS treatment group it was 1.6319 + 0.1325,in 10 mg/L LPS treatment group it was 2.4762 ±0.1380,and in 15 mg/L LPS treatment group it was 1.6642 ±0.0938.There were statistically significant differences between the experimental groups and control group (all P ＜ 0.01).Conclusion miR-646 may have a biological function in acute respiratory distress syndrome through inhibiting the transcription of SP-C.