Effect of OGD/R on cell survival and apoptosis in the presence or absence of miR-126 mimics in HUVECs. Cells were exposed to OGD for 4 h, followed by reoxygenation for 6, 12 and 24 h. (A) The cell viability of each group was determined by CCK-8 assay. (B) LDH release from HUVECs was measured using a LDH Cytotoxicity assay kit. (C) miR-126 expression was determined via RT-qPCR. HUVECs were transfected with miR-126 m or miR-NC, and (D) miR-126 expression was determined via RT-qPCR. HUVECs were transfected with miR-126 m or miR-NC before OGD (4 h)/R (24 h) exposure. (E) The cell viability of each group was determined by CCK-8 assay. (F) LDH release from HUVECs was measured using a LDH Cytotoxicity assay kit. (G) The rate of apoptosis was detected by Annexin V/PI double staining followed by flow cytometry. Data are presented as the mean ± SD of three independent experiments. *P<0.05 and **P<0.01 vs. control group; ##P<0.01 vs. miR-NC or miR-NC + OGD/R group. miR-126 m, miR-126 mimics; miR-NC, miR-negative control; miR, microRNA; OGD, oxygen-glucose deprivation; R, reoxygenation; HUVEC, human umbilical vein endothelial cell; LDH, lactate dehydrogenase; RT-qPCR, reverse transcription-quantitative PCR.