Electrospun PLGA/PCL/OCP nanofiber membranes promote osteogenic differentiation of mesenchymal stem cells (MSCs)

Abstract

Nanofibers as niche-biomimetic scaffolds hold promise in guided bone regeneration (GBR). Here we fabricated poly (lactic-co-glycolic acid) (PLGA)/poly(caprolactone) (PCL)-doped octacalcium phosphate (OCP) nanofiber membranes via electrospinning and investigated the osteogenic behavior of marrow mesenchymal stem cells (MSCs) on the membranes. By adjusting different ratio of OCP to PLGA/PCL, three hybrid stents including PLGA/PCL, PLGA/PCL/2 wt%OCP, PLGA/PCL/4wt%OCP were successfully prepared. The PLGA/PCL/OCP membranes showed a decrease in fiber diameter compared with PLGA/PCL, leading to enhanced mechanical strength. In-vitro studies showed that PLGA/PCL/OCP membranes better supported cell adhesion, spreading and proliferation than PLGA/PCL. The incorporation of OCP via electrospinning also endowed the membranes with osteoinductive capacity, as evidenced by activation of ALP activity, increased gene expression of bone specific markers (such as Runx2, ALP, Col 1a1, OPN, OCN, BMP2), and mineral nodules formation compared to PLGA/PCL. Comparatively, PLGA/PCL/4wt%OCP showed better mechanical and biological performance than PLGA/PCL/2 wt%OCP, demonstrating the role of OCP in nanofiber membranes. Thus, the electrospun PLGA/PCL/OCP nanofiber membranes can be potentially developed as a promising hybrid stent for GBR.

Keywords: Electrospinning; Guided bone regeneration; MSCs; Octacalcium phosphate; PCL; PLGA.