Effect of luteolin on the proliferation, apoptosis and Hippo/Yes-related protein pathway of lung epithelial cells induced by bleomycin

  Objective  To explore the effect of luteolin(Lut)on the proliferation, apoptosis and the Hippo/Yes-related protein (YAP) pathway of human lung epithelial cell (BEAS-2B cells) induced by bleomycin(BLM).

  Methods  BEAS-2B cells were cultured in vitro, and induced with 4, 8, 12 and 24 μg/mL BLM for 12, 24 and 48 h, respectively, to determine the BLM induction concentration and time. The BEAS-2B cells were divided into control group, BLM group, and Lut low, medium and high concentration groups. After 24 hours of cell culture in each group, the morphological changes of the cells were observed with an inverted microscope; the cell proliferation ability was detected by the CCK-8 method; the rate of cell apoptosis was detected by flow cytometry; Western blot was used to detect Hippo/YAP pathway related proteins-mammalian Sterile20-like 1(MST1), the large tumour suppressor 1 (LAST1) and YAP phosphorylation levels.

  Results  The half maximal inhibitory concentration (IC50) of BEAS-2B cells after 24 hours of BLM induction was about 8 μg/mL, so 8 μg/mL BLM was selected to induce cells for 24 hours. Compared with the control group, the BLM group had smaller cells, irregular edges, increased intercellular space, the cell proliferation ability, MST1, LAST1 and YAP phosphorylation levels significantly decreased, and apoptosis rate significantly increased (P < 0.05); compared with the BLM group, the cell morphology of the Lut low, medium, and high concentration groups tended to be normal, and the cell proliferation ability, MST1, LAST1 and YAP protein phosphorylation levels increased successively (P < 0.05), and the rate of apoptosis decreased successively (P < 0.05).

  Conclusion  Lut may activate the Hippo/YAP signaling pathway in BEAS-2B cells, increase the proliferation of BEAS-2B cells induced by BLM, and inhibit cell apoptosis.