Effects of Autologous Oxygen-Releasing Nano-Bionic Scaffolds Combined with Bone Marrow Mesenchymal Stem Cells on Proliferation and Differentiation of Bone Marrow Mesenchymal Stem Cells

The key issues in bone tissue engineering are the selection of bioactive scaffold materials and seed cells. Bone marrow mesenchymal stem cells (BMSCs) have a potential application. It was shown that autologous oxygen-releasing nano-bionic scaffolds exhibit well osteogenic properties and can release oxygen from the body to provide oxygen supply for bone transplantation. However, the effects of autologous oxygen-releasing nano-bionic scaffolds combined with BMSCs on the proliferation and differentiation of BMSCs have not been reported. Nano-hydroxyapatite/chitosan composite scaffold and autologous oxygen-releasing nano-bionic scaffold were prepared respectively. Rat BMSCs were isolated and cultured in vitro. BMSCs were inoculated into nano-hydroxyapatite/chitosan composite scaffold as control group and autologous oxygen-releasing nano-bionic scaffolds as experimental group followed by analysis of BMSCs proliferation by MTT assay, Caspase 3 activity by Caspase 3 activity kit, the ALP activity, the RUNX2 and OPN mRNA expressions were by Real-time PCR, FAPD4 and PPAR gamma 2 protein expressions by Western blot as well as TGF beta/Smad signaling pathway activity by Real-time PCR. Compared with control group, BMSCs proliferation was significantly enhanced, the activity of Caspase 3 was significantly decreased, the activity of ALP was significantly increased, RUNX2 and OPN mRNA expressions were significantly elevated, FABP4 and PPAR gamma 2 levels were significantly downregulated, and TGF beta 1, Smad2, and Smad7 expressions were significantly upregulated in experimental group (P < 0.05). However, autologous oxygen-releasing nano-bionic scaffolds combined with BMSCs can promote BMSCs proliferation, reduce cell apoptosis, enhance osteogenic differentiation, and inhibit adipogenic differentiation through TGF beta/Smad signaling pathway.