The microRNA-21-5p regulation of type Ⅱ alveolar epithelial cell apoptosis / 中华危重病急救医学

ABSTRACT

Objective:To explore whether microRNA-21-5p (miR-21-5p) has the effect of anti-apoptosis of human alveolar typeⅡ epithelial cells (ATⅡ).Methods:ATⅡ cells derived from the human were cultured in vitro and used for experiments when the cells were grown until the presence of lamellar bodies and microvilli were observed by light microscope. The cells were divided into blank control group (direct culture), hydrogen peroxide (H 2O 2) injury group (cultured with 0.5 mmol/L H 2O 2), and miR-21-5p overexpression group (using miR-21-5p with a multiplicity of infection (MOI) of 100 lentiviral overexpression vector with 0.5 mmol/L H 2O 2) and miR-21-5p empty virus control group (miR-21-5p lentiviral blank vector was co-cultured with 0.5 mmol/L H 2O 2). In each group, cell proliferation was detected by cell counting kit-8 (CCK-8) at 0, 12, 24, 36, and 48 hours of cell culture; cell apoptosis was detected by flow cytometry at 24 hours of culture. Results:① Cell proliferation activity test results: with the extension of cell culture time, the cell proliferation activity of the blank control group gradually increased, while the cell proliferation activity gradually decreased after the addition of 0.5 mmol/L H 2O 2. However, the cells proliferation activity in the miR-21-5p overexpression group decreased more slowly than that in the H 2O 2 injury group and the miR-21-5p empty virus control group, and the cell proliferation activity at 48 hours was significantly higher than the H 2O 2 injury group and the miR-21-5pempty virus control group ( A value 0.295±0.005 vs. 0.184±0.005, 0.169±0.002, both P < 0.05). It showed that both H 2O 2 and lentivirus accelerated cell damage, while miR-21-5p could reduce cell apoptosis. ② Apoptosis rate test results: compared with the blank control group, the apoptosis rate increased significantly after adding 0.5 mmol/L H 2O 2; while the apoptosis rate of the miR-21-5p overexpression group was lower than that of the H 2O 2 injury group and miR-21-5p empty virus control group [early apoptosis rate (14.31±0.12)% vs. (24.50±0.12)%, (23.41±0.13)%; late apoptosis rate (8.12±0.13)% vs. (9.71±0.11)%, (10.41±0.15)%; overall apoptosis rate (22.33±0.12)% vs. (34.21±0.10)%, (33.82±0.14)%; all P < 0.05], which further proved that miR-21-5p had anti-apoptotic effects. Conclusion:miR-21-5p has an anti-apoptotic effect on human ATⅡ.