Erratum: A novel vehicle-like drug delivery 3D printing scaffold and its applications for a rat femoral bone repairing in vitro and in vivo: Erratum.

[This corrects the article DOI: 10.7150/ijbs.37552.].

A novel 3D printed bioactive scaffolds with enhanced osteogenic inspired by ancient Chinese medicine HYSA for bone repair.

Some traditional Chinese medicine (TCM) has been applied in bone repair, however, hydroxy-safflower yellow A (HYSA), one composition of safflower of the typical invigorating the circulation of TCM, has little been studied in orthopedics field for osteogenesis and angiogenesis clinically. Herein, we hypothetically speculated that the synthetic bioactive glasses (BG, 1393) scaffolds carried HYSA by a 3D print technique could enhance osteogenic repair properties. Notably, scaffolds coating chitosan/sodium alginate endowed with excellent drug control release ability, and significantly improved the BG mechanical strength. HYSA was loaded into BG scaffolds by coating chitosan/sodium alginate film, and the osteogenesis and angiogenesis of the HYSA/scaffolds were evaluated in vitro and in vivo. In vitro the cell culture results exhibited that the high dose of HYSA (0.5 mg/ml) loaded scaffolds can promote the proliferation of bone marrow stromal cells (rBMSCs) and migration, tubule formation of human umbilical vein endothelial cells (HUVECs). The active alkaline phosphatase (ALP) of rBMSCs can also be improved by the high dose of HYSA/scaffolds. Results of qRT-PCR and Western blot indicated that the high dose of HYSA/scaffolds can up-regulate ALP, OCN, OPN and RUNX-2 expression and relative protein secretion of the HIF-1α and BMP-2. In the animal experiment, the high dose of HYSA/scaffolds has a significantly better capacity to promote new bone formation than the undoped scaffolds at 8 weeks post-surgery. Thus, our results claimed that the novel HYSA/scaffolds hold the substantial potential to be further developed as effective and safe bone tissue engineering biomaterials for bone regeneration by combining enhanced osteogenesis and angiogenesis.

A novel vehicle-like drug delivery 3D printing scaffold and its applications for a rat femoral bone repairing in vitro and in vivo.

The high surface area ratio and special structure of mesoporous bioactive glass (MBG) endow it with excellent physical adsorption of various drugs without destroying the chemical activity. Silicate 1393 bioactive glass (1393) is famous for its fantastic biodegradability and osteogenesis. Herein, we have built a novel vehicle-like drug delivery 3D printing scaffold with multiplexed drug delivery capacity by coating MBG on the surface of 1393 (1393@MBG). Furthermore, we have applied DEX and BMP-2 on the 1393@MBG scaffold to endow it with antibacterial and osteogenic properties. Results indicated that this 1393@MBG scaffold could effectively load and controlled release BMP-2, DNA and DEX, which can be applied for orthopedic treatment. The in vitro study showed that the DEX loaded 1393@MBG exhibited excellent antibacterial ability, which was evaluated by Staphylococcus aureus (S. aureus), and the BMP-2 loaded 1393@MBG can improve the alkaline phosphatase (ALP) activity and upregulate the expression of osteogenesis-related genes (OCN and RUNX2) of human bone mesenchymal stem cells (hBMSCs). Moreover, the in vivo study further confirmed that the BMP-2 loaded 1393@MBG group showed better osteogenic capacity as compared to that of the 1393 group in a rat femoral defect. Together, these results suggested that the vehicle-like drug delivery 3D printing scaffold 1393@MBG could be a promising candidate for bone repair and relative bone disease treatment.

Hypoxia-Mimicking Cobalt-Doped Borosilicate Bioactive Glass Scaffolds with Enhanced Angiogenic and Osteogenic Capacity for Bone Regeneration.

The osteogenic capacity of synthetic bone substitutes is will be highly stimulated by a well-established functional vascularized network. Cobalt (Co) ions are known that can generate a hypoxia-like response and stimulates the production of kinds of angiogenic factors. Herein, we investigated the mechanism of cobalt-doped bioactive borosilicate (36B2O3, 22CaO, 18SiO2, 8MgO, 8K2O, 6Na2O, 2P2O5; mol%) glass scaffolds for bone tissues repairing and blood vessel formation in the critical-sized cranial defect site of rats and their effects on the hBMSCs in vitro were researched. The scaffolds can control release Co2+ ions and convert into hydroxyapatite soaking in simulative body fluids (SBF). The fabircated scaffolds without cytotoxic strongly improves HIF-1α generation, VEGF protein secretion, ALP activity and upregulates the expression of osteoblast and angiogenic relative genes in hBMSCs. Eight weeks after implantation, the bioactive glass scaffolds with 3wt % CoO remarkablely enhance bone regeneration and blood vascularized network at the defective site. In conclusion, as a graft material for bone defects, low-oxygen simulated cobalt-doped bioactive glass scaffold is promising.