[Puerarin attenuates PM2.5-induced vascular endothelial cells injury via ERK1/2 signaling pathway]

To investigate the effect and the mechanism of puerarin in attenuating PM2.5-induced human umbilical vein endothelial cells (EA.hy926) injury, the samples of fine particulate matter (PM2.5) were collected and made into suspension. Different concentrations of PM2.5 (0,20, 200, 400 mg•L⁻¹) were used to contaminate EA.hy926 cells for 24 h. The cells survival rate was detected by MTT assay; cells apoptosis of EA.hy926cells was detected by flow cytometry; the protein levels of p-ERK1/2, Bax and Bcl-2 were detected by Western blot; the contents of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), malonaldehyde (MDA), and the activities of superoxide dismutase (SOD) and lactic dehydrogenase (LDH) were measured by ELISA. Puerarin at different concentrations (10, 50, 100 μmol•L⁻¹) or a specific inhibitor of ERK1/2 pathway PD98059 (20 μmol•L-1) was added into the EA.hy926 cells to observe the intervention effect and mechanism of puerarin. Compared with the control group, PM2.5 reduced the cells survival rate, up-regulatedp-ERK1/2 protein level and Bax/Bcl-2 ratio in a dose dependent manner to promote apoptosis; increased the contents of TNF-α, IL-6 and MDA, the activity of LDH, but decreased SOD activity in the EA.hy926 cells (P<0.05). Compared with PM2.5 group, puerarin increased the cells survival rate, down-regulated p-ERK1/2 protein level and Bax/Bcl-2 ratio in a dose dependent manner to inhibit the apoptosis; decreased the contents of TNF-α, IL-6 and MDA, the activity of LDH, but increased SOD activity in the EA.hy926 cells (P<0.05). The results indicated that puerarin could attenuate PM2.5-induced EA.hy926 cells injury via the inhibition of ERK1/2 pathway.