M-keratin induces regeneration of bone tissue in Sprague-Dawley rats.

Mineralized keratin (M-keratin) has previously been shown to promote the differentiation of dental pulp stem cells (DPSCs) into odontoblasts; however, the in vivo biological effects and biocompatibility of this material have not yet been illustrated. To investigate this, we first prepared M-keratin (defined as keratin that has been mineralized in Simulated body fluid) nanoparticles, then, implanted these into a femoral injury Sprague-Dawley Rats model. Signs of bone regeneration were observed and/or detected by CT scan, HE stains, Masson stain, and Western blot. We found the regeneration of bone tissue was accelerated in the 28 days following implantation, seen as an up-regulation in the expression of Runx2, ALP, BMP-2, and OSX proteins. GO enrichment analysis and KEGG pathway enrichment analysis showed that cell membrane regulation and calcium ion signaling pathway were significantly activated, and it was revealed that multiple genes served as cross-linking hubs between different signaling pathways to jointly promote bone tissue repair. With this study, we hope to provide a theoretical basis for the clinical treatment of bone defect diseases.