3D printing of Cu-doped bioactive glass composite scaffolds promotes bone regeneration through activating the HIF-1α and TNF-α pathway of hUVECs

Biomater Sci. 2021 Aug 21;9(16):5519-5532. doi: 10.1039/d1bm00870f. Epub 2021 Jul 8.

Abstract

The increasing insight into the molecular and cellular processes within the angiogenic cascade assists in enhancing the survival and integration of engineered bone constructs. Copper-doped bioactive glass (Cu-BG) is now a potential structural component of the novel scaffolds and implants used in orthopedic and dental repairs. However, it is difficult for BG, especially micro-nano particles, to be printed into scaffolds and still retain its biological activity and ability to biodegrade. Additionally, the mechanisms of the copper-stimulating autocrine and paracrine effects of human umbilical vein endothelial cells (hUVECs) during repair and regeneration of bone are not yet clear. Therefore, in this study, we created monodispersed micro-nano spherical Cu-BG particles with varying copper content through a sol-gel process. Through in vitro tests, we found that Cu-BG enhanced angiogenesis by activating the pro-inflammatory environment and the HIF-1α pathway of hUVECs. Furthermore, 2Cu-BG diluted extracts directly promoted the osteogenic differentiation of mouse bone mesenchymal stem cells (BMSCs) in vitro. Then, a new 3D-printed tyramine-modified gelatin/silk fibroin/copper-doped bioactive glass (Gel/SF/Cu-BG) scaffold for rat bone defects was constructed, and the mechanism of the profound angiogenesis effect regulated by copper was explored in vivo. Finally, we found that hydrogel containing 1 wt% 2Cu-BG effectively regulated the spatiotemporal coupling of vascularization and osteogenesis. Therefore, Cu-BG-containing scaffolds have great potential for a wide range of bone defect repairs.

MeSH terms

  • Bone Regeneration
  • Glass
  • Human Umbilical Vein Endothelial Cells
  • Humans
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Osteogenesis*
  • Printing, Three-Dimensional
  • Skull
  • Tissue Scaffolds
  • Tumor Necrosis Factor-alpha*

Substances

  • HIF1A protein, human
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Tumor Necrosis Factor-alpha