FeS2-incorporated 3D PCL scaffold improves new bone formation and neovascularization in a rat calvarial defect model

Abstract

Three-dimensional (3D) scaffolds composed of various biomaterials, including metals, ceramics, and synthetic polymers, have been widely used to regenerate bone defects. However, these materials possess clear downsides, which prevent bone regeneration. Therefore, composite scaffolds have been developed to compensate these disadvantages and achieve synergetic effects. In this study, a naturally occurring biomineral, FeS2, was incorporated in PCL scaffolds to enhance the mechanical properties, which would in turn influence the biological characteristics. The composite scaffolds consisting of different weight fractions of FeS2 were 3D printed and compared to pure PCL scaffold. The surface roughness (5.77-fold) and the compressive strength (3.38-fold) of the PCL scaffold was remarkably enhanced in a dose-dependent manner. The in vivo results showed that the group with PCL/FeS2 scaffold implanted had increased neovascularization and bone formation (2.9-fold). These results demonstrated that the FeS2 incorporated PCL scaffold might be an effective bioimplant for bone tissue regeneration.

Bioinformatic analysis of the molecular mechanisms underlying the progression of bone defects

“…All animal experiments were approved by the Ethics Committee of Nanjing Medical University. 12 weeks old Sprague Dawley rats were used to performed calvarial defect models as previously described ( 12 ). In brief, under anesthetic conditions, defects (4 or 8 mm in diameter) were created on the right parietal bone of the skull using a round burr attached to drill.…”

“…The transcriptome data of GSE20980 based on the GPL1335 platform (Affymetrix Rat Genome 230 2.0 Array) were obtained from the National Center for Biotechnology Information Gene Expression Omnibus database. 1 According to the traditional definition, a critical size defect (CSD) is the minimum defect size that cannot be healed spontaneously, where 8 mm is commonly considered as the CSD of rat calvarial defects (10)(11)(12). In this experiment, circular defects of 8 mm (CSD) or 4 mm (none-CSD, NCSD) were created in the calvaria by a drill.…”