Figure 1.

Cell senescence induced by oxidative stress. (A) Cell viability was determined by Cell Counting Kit-8. (B) Cell senescence was detected by SA-β-gal staining. (C) The cell cycle was determined by flow cytometry. (D) The miR-20b level was detected by reverse transcription quantitative-PCR. The human umbilical vein endothelial cells were randomly divided into 5 groups and treated with different concentrations of H₂O₂ (0, 10, 50, 100 and 500 µM). The blank group (0 µM H₂O₂) was cultured in normal medium. The H₂O₂ group was incubated by normal medium with different concentrations of H₂O₂. The experiments were repeated in triplicate. ^**P<0.001 vs. 0 µM H₂O₂. miR, microRNA; OD, optical density; SA-β-gal, SA-β-galactosidase.