Figure 4.

The IGFBP3-Orai signaling complexes affected the endothelial barrier and migration of HCAECs. (A) Representative western blot images and (B) summary data showing VE-cadherin expression level in HCAECs cultured in NG or HG medium. (C) Representative western blot images and (D) summary data showing IGFBP3 siRNA knockdown of VE-cadherin level. (E) High glucose-induced TER was examined via transendothelial electrical resistance in vitro after HCAECs were cultured in HG medium for 7 days. (F) FD20 permeability was tested in monolayer aortic endothelial cells through transwell permeability assay. (G, H) Summary data showing TER and FD20 permeability in HCAECs cultured in HG or NG medium for 7 days in the presence or absence of the SOCE agonist ATP (100 µM) or the SOCE inhibitor BTP2 (10 µM). The migration of human colonic cells was investigated using the wound-repair ratio. (I) Representative photos showing cell migration of HCAECs cultured in HG or NG medium for 7 days in the presence or absence of ATP (100 µM) or BTP2 (10 µM), and the ratios of cell migration are shown in (J). (K) Representative photos showing cell migration of HCAECs transfected with IGFBP3 siRNA and cultured in HG medium for 7 days, and the ratios of cell migration are shown in (L). β-tubulin or GAPDH was used as loading controls. Values represent mean±SEM (n=4–5 samples). *P<0.05, **P<0.01, ***P<0.001 compared with NG-cultured cells or control groups. FD20, fluorescein isothiocyanate (FITC)-labeled dextran 20 kDa; GAPDH, glyceraldehyde 3-phosphate dehydrogenase; HCAECs, human coronary artery endothelial cells; HG, high glucose; IGFBP3, insulin-like growth factor binding protein 3; NG, normal glucose; OD, optical density; siRNA, small interfering RNA; SOCE, store-operated Ca²⁺ entry; TER, transendothelial electrical resistance; VE-cadherin, vascular endothelial cadherin.