Alumina-Hydroxyapatite nanopowder promote proliferation andOsteogenic differentiation of mesenchymal stem cells

Hydroxyapatite (HA) is a promising bioactive bioceramic for bone tissue regeneration due toits good chemical and biological similarity to mineral phase of natural bone. These positivetraits are tempered by its low toughness and strength that limits its application in load-bearingconditions. A good approach for improving the mechanical properties of this bioceramics isfabrication of hydroxyapatite based composites with reinforcements such as alumina, titaniaand zirconia. Although investigation on the mechanical properties of this composites hasshown good effects of alumina as reinforcement, less attention has been paid to its biologicalproperties. In this study, HAp-Al۲O۳ nanocomposite powder with ۱۰, ۲۰, ۳۰ wt. % of aluminawas synthesized via sol-gel method. Mesenchymal stem cells (MSCs) derived from bonemarrow of neonatal rabbits were cultivated in the culture medium containing a concentrationof ۱۰۰ μg/ml of powders for up to ۱۴ days. Cytotoxicity, proliferation and differentiation ofMSCs into osteoblast cells were determined using MTT assay, live/dead assay usingfluorescence dyes, alkaline phosphatase (ALP) activity and alizarin red staining. After ۱۴days of culture, the sample containing ۲۰% alumina showed the highest cell viability incomparison with others (۱۰۳.۶ %). The highest ALP activity was observed in HAp-۳۰%Al۲O۳ and HAp-۲۰% Al۲O۳ sample, respectively. Moreover, the formation of mineralizednodules in MSCs upon treatment with HAp-۲۰% Al۲O۳ sample could produce more bonenodules. These findings are of important interest to develop materials for critical bone repair

کلیدواژه ها:

Hydroxyapatite ، Alumina ، nanopowder ، mesenchymal stem cells ، differentiation