Upregulation of Periostin Prevents High Glucose-Induced Mitochondrial Apoptosis in Human Umbilical Vein Endothelial Cells via Activation of Nrf2/HO-1 Signaling.

BACKGROUND/AIMS High glucose-induced oxidative damage to endothelial cells plays a central role in the pathogenesis of diabetic vascular complications. This study was undertaken to explore the role of periostin in high glucose-induced endothelial cell apoptosis and associated molecular mechanisms. METHODS Human umbilical vein endothelial cells (HUVECs) were exposed to high glucose (33.3 mmol/L) and examined for the expression of periostin. The effects of periostin upregulation on high glucose-induced apoptosis, mitochondrial dysfunction, and reactive oxygen species (ROS) production were determined. The activation of nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) by periostin was checked. HO-1 knockdown experiments were done to confirm its role in the action of periostin in high glucose-exposed HUVECs. RESULTS High glucose significantly upregulated the expression of periostin in HUVECs. Enforced expression of periostin attenuated high glucose-induced apoptosis in HUVECs, as determined by TUNEL staining and caspase-3 activity assay. Periostin overexpression prevented loss of x0394;x03C8;m, release of mitochondrial cytochrome c, and dysregulation of Bcl-2 and Bax in high glucose-exposed HUVECs. Periostin upregulation suppressed high glucose-induced ROS generation and activated the Nrf2/HO-1 signaling. HO-1 silencing restored high glucose-induced ROS generation and apoptotic response in periostin-overexpressing HUVECs. CONCLUSION Periostin mitigates high glucose-induced mitochondrial apoptosis in endothelial cells, via activation of Nrf2/HO-1 signaling and reduction of ROS formation. Further studies are warranted to explore the therapeutic potential of periostin in diabetic vascular complications.