Nanohydroxyapatite-Blasted Bioactive Surface Drives Shear-Stressed Endothelial Cell Growth and Angiogenesis.

Area of Science:

• Biomaterials Science
• Cell Biology
• Dental Implantology

Background:

• Nanosized crystalline hydroxyapatite coating (HAnano®) is known to accelerate dental implant osteointegration.
• The mechanism by which HAnano® enhances osteointegration is hypothesized to involve angiogenesis.

Purpose of the Study:

• To investigate the effect of HAnano® on angiogenesis in vitro.
• To elucidate the molecular mechanisms underlying HAnano®-induced angiogenesis.

Main Methods:

• Human umbilical vein endothelial cells (HUVECs) were exposed to HAnano®-enriched medium or dual acid etching (DAE) control.
• Gene expression analysis focused on angiogenesis-related genes (VEGF, eNOS, AKT), cell cycle regulators (CDK4, p21, p15), and extracellular matrix remodeling.
• Endothelial cell migration assays were performed.

Main Results:

• HAnano® significantly upregulated genes associated with endothelial cell viability and performance (VEGF, eNOS, AKT).
• HAnano® promoted endothelial cell migration and extracellular matrix remodeling, suggesting a dual role in VEGF expression and cell growth control.
• HAnano® increased CDK4 expression while decreasing suppressor genes (p21, p15), indicating promotion of cell cycle progression.

Conclusions:

• HAnano®-coated surfaces stimulate angiogenesis by promoting a proliferative and migratory phenotype in endothelial cells.
• This study provides novel insights into the osseointegration mechanism of dental implants with nanosized hydroxyapatite coatings.