Silk fibroin-chitosan aerogel reinforced by nanofibers for enhanced osteogenic differentiation in MC3T3-E1 cells

Int J Biol Macromol. 2023 Apr 1:233:123501. doi: 10.1016/j.ijbiomac.2023.123501. Epub 2023 Feb 2.

Abstract

Proper bone scaffolds should be biocompatible, mechanically robust and porous for cell migration. Here, pure silk fibroin (SF)- chitosan (CS) aerogel scaffolds reinforced with different amount of SF nanofibers (SF-CS/NF1%, SF-CS/NF2% and SF-CS/NF3%) are prepared for bone regeneration. Surface morphology and composition were analyzed to ensure successful integration of each component. Incorporating 3 % nanofibers endowed the aerogels with a resistance to 3.5 times the compressive stress of the pure SF-CS aerogels. The benefits of nanofibers were also confirmed by the high porosity of 72.3 ± 1.3 %, the regulated pore size and the high-water uptake ratio of 1770.4 ± 156.8 %. Enhanced cell viability of the aerogel scaffolds was verified with Cell Counting Kit-8 (CCK-8) assays, and confocal microscopy and scanning electron microscopy (SEM) images were taken to assess the cell migration and distribution. The cell differentiation on the aerogel scaffolds was evaluated with enzyme-linked immunosorbent assay (ELISA). Significantly higher level of Collagen type I (Col-I), osteocalcin (OCN), osteopontin (OPN), and alkaline phosphatase (ALP) expression was observed on SF-CS/NF3% aerogels. This biocompatible nanofiber-reinforced aerogel scaffold facilitates osteogenic differentiation by rougher surface, enhanced mechanical strength and well-regulated pores. Thus, as-prepared scaffolds may be further applied in bone regeneration field.

Keywords: Aerogel; Nanofibers; Osteogenesis.

MeSH terms

  • Cell Differentiation
  • Cell Proliferation
  • Chitosan*
  • Fibroins*
  • Nanofibers*
  • Osteogenesis
  • Porosity
  • Tissue Engineering / methods
  • Tissue Scaffolds

Substances

  • Fibroins
  • Chitosan