Figure 5

Effects of inhibition of mitochondrial respiration on glycolysis and HUVEC proliferation. Specific inhibitors of the oxidative phosphorylation, oligomycin A (1.5 µM) or antimycin A (2.5 µM)/rotenone (1.25 µM), reduced mitochondrial respiration (OCR) (a) and increased glycolysis (ECAR) (b) in HUVECs after 24 h of treatment. (c) Inhibition of the oxidative phosphorylation induced an increase in the percentage of tip cells. (d) Cell proliferation assay of HUVECs in the presence of oligomycin A or antimycin A/rotenone expressed as percentages of cells in the G0/G1, S, and G2M phase after FACS analysis of fluorescence of incorporated EdU. (e) Inhibition of the oxidative phosphorylation lowered percentages of HUVECs in the G2M phase and late S phase and elevated percentages of HUVECs in the G0/G1 phase. OCR and ECAR measurements were represented as fold change compared to control basal OCR and ECAR levels, respectively. Results are shown as means ± SEM of experiments with HUVECs of at least 3 donors. *P < 0.05, **P < 0.01, and ***P < 0.001 as compared to non-tip cells (Unpaired Student’s t-test).