Osteogenic Differentiation of Human Adipose-Derived Stem Cells(hADSCs) on a Dexamethasone Eluting Nanofiber Scaffolds

Abstract

Dexamethasone(DEX), a synthetic steroidal anti -inflammatory drug, is an efficient and dependable drug that induces osteogenic differentiation. The aim of this study is to fabricate the DEX loaded PLGA nanofibers by electrospinning method. Adipose-derived stem cells(ADSCs) were seeded into the nanofiber and the sustained release of DEX from PLGA nanofiber scaffolds promoted their osteogenic differentiation. The properties of DEX loaded PLGA nanofiber scaffold were characterized by scanning electron microscopy(SEM) and the release kinetics of DEX from PLGA nanofibers in vitro(I It to 14 days) was evaluated by high performed liquid chromatography(HPLC). To evaluate the cellular response of the ADSCs seeded onto DEX loaded PLGA nanofiber, we performed F-actin, cytotoxicity, alkaline phosphatase activity, alizarin red S, von Kossa staining and immunocytochemistry assays for osteogenic differentiation. DEX loaded PLGA nanofiber scaffold was observed to have sustained release in vitro during experimental periods. The cytotoxicity test of the DEX loaded PLGA nanofiber scaffold indicated there was almost no-toxic effects in regards to proliferation and differentiation of adipose-derived stem cells(ADSCs) as compared with a control. Alkaline phosphatase activity and alizarin red S were more significantly increased after 14days with increased DEX concentration of PLGA nanofiber scaffold than with PLGA nanofiber only. Also, von Kossa staining results confirmed a larger area of calcium deposition with increased DEX concentration of PLGA nanofiber scaffold. We observed that osteocalcin was also increased with increasing DEX concentration. These results demonstrate that DEX acts as an osteogenic inductive factor, and increased DEX concentration promoted more osteogenic differentiation of ADSCs. In conclusion, DEX loaded PLGA nanofiber would be valuable tool for bone tissue regeneration.