The polycaprolactone/silk fibroin/carbonate hydroxyapatite electrospun scaffold promotes bone reconstruction by regulating the polarization of macrophages

Abstract

Macrophages are known to modulate the osteogenic environment of bone regeneration elicited by biological bone grafts. Alteration in certain chemical components tends to affect macrophages polarization. Comparatively to hydroxyapatite (HAp), carbonate hydroxyapatite (CHA) consists of 7.4 (wt%) carbonate ions and more closely resembles the mineral content of bone. It remains unknown whether CHA scaffolds or HA scaffolds have better osteogenic properties. In this study, we fabricated PCL/SF scaffold, PCL/SF/HAp scaffold and PCL/SF/CHA scaffold using the electrospinning technique. Despite comparable mechanical properties, the PCL/SF/CHA scaffold exhibited better osteogenic properties than the PCL/SF/HAp scaffold. Although no significant differences were observed between the two scaffolds for promoting osteoblast differentiation in vitro, the PCL/SF/CHA group appeared to be more effective at promoting bone regeneration in cranial defects in vivo. The PCL/SF/CHA scaffold was found to promote macrophage polarization toward M2 via activating the JAK/STAT5 pathway which caused a pro-osteogenic microenvironment to facilitate osteoblast differentiation. The results of this study indicated a higher potential of CHA to substitute HAp in the production of bone scaffolds for better bone regeneration.

Evaluation and Application of Silk Fibroin Based Biomaterials to Promote Cartilage Regeneration in Osteoarthritis Therapy

“…The SF/calcium phosphate material has good biocompatibility and mechanical properties as a bone repair scaffold, providing a good growth space for osteoblast differentiation. In addition, the injectability exhibited by the hydrogel and its use as a drug carrier allows the hydrogel to fit closely to the interface of the cartilage defect, thus improving the integration effect [ 139 ].…”

Selenium-modified bone cement promotes osteoporotic bone defect repair in ovariectomized rats by restoring GPx1-mediated mitochondrial antioxidant functions

“…In addition, recent studies have confirmed that some inorganic metal ions or drug molecules combined with CPC can promote the repair of osteoporotic fractures or bone defects [ 20 , 21 ]. Silk fibroin (SF) is a kind of natural high molecular protein secreted by silkworm and has a wide array of medical applications owing to its good biocompatibility, degradability, modification and stable mechanical properties [ 22 , 23 ]. It has been reported that SF combined with CPC can be used for implant fixation and bone tissue defects [ 24 ], and both CPC and SF have good loading properties for various drugs and biological factors [ 25 , 26 ].…”