Preparation of poly(ethylene glycol)/polylactide hybrid fibrous scaffolds for bone tissue engineering

Abstract

Polylactide (PLA) electrospun fibers have been reported as a scaffold for bone tissue engineering application, however, the great hydrophobicity limits its broad application. In this study, the hybrid amphiphilic poly(ethylene glycol) (PEG)/hydrophobic PLA fibrous scaffolds exhibited improved morphology with regular and continuous fibers compared to corresponding blank PLA fiber mats. The prepared PEG/PLA fibrous scaffolds favored mesenchymal stem cell (MSC) attachment and proliferation by providing an interconnected porous extracellular environment. Meanwhile, MSCs can penetrate into the fibrous scaffold through the interstitial pores and integrate well with the surrounding fibers, which is very important for favorable application in tissue engineering. More importantly, the electrospun hybrid PEG/PLA fibrous scaffolds can enhance MSCs to differentiate into bone-associated cells by comprehensively evaluating the representative markers of the osteogenic procedure with messenger ribonucleic acid quantitation and protein analysis. MSCs on the PEG/PLA fibrous scaffolds presented better differentiation potential with higher messenger ribonucleic acid expression of the earliest osteogenic marker Cbfa-1 and mid-stage osteogenic marker Col I . The significantly higher alkaline phosphatase activity of the PEG/PLA fibrous scaffolds indicated that these can enhance the differentiation of MSCs into osteoblast-like cells. Furthermore, the higher messenger ribonucleic acid level of the late osteogenic differentiation markers OCN ( osteocalcin ) and OPN ( osteopontin ), accompanied by the positive Alizarin red S staining, showed better maturation of osteogenic induction on the PEG/PLA fibrous scaffolds at the mineralization stage of differentiation. After transplantation into the thigh muscle pouches of rats, and evaluating the inflammatory cells surrounding the scaffolds and the physiological characteristics of the surrounding tissues, the PEG/PLA scaffolds presented good biocompatibility. Based on the good cellular response and excellent osteogenic potential in vitro, as well as the biocompatibility with the surrounding tissues in vivo, the electrospun PEG/PLA fibrous scaffolds could be one of the most promising candidates in bone tissue engineering.

Synthesis and characterization of CaO-loaded electrospun matrices for bone tissue engineering

“…Considering that hydrophilic matrices/scaffolds may increase cell viability, the positive cell response obtained here corroborates with previous studies [36–40]. Interestingly, the present findings also agree with a previous study, which indicated that cell proliferation increased over time [51]. Previous studies reported on the enhanced mineralized matrix nodule formation in the presence of high Ca ion concentrations in dental pulp stem cells [52] and osteoblasts [53].…”

IGF-1/IGF-1R/hsa-let-7c axis regulates the committed differentiation of stem cells from apical papilla

“…Some osteogenic markers (e.g., ALP, RUNX2, OSX and COL-I) are secreted during the early stage of osteo/odontoblastic differentiation, whereas OCN is involved in the late-stage differentiation process30313233. ALP is expressed and secreted from a proliferation phase to the deposition of mature extracellular matrix including calcium phosphate during the cell differentiation34.…”

“…RUNX2 and OSX are expressed in osteogenic mesenchyme in all stages of craniofacial bone development, and RUNX2 can modulate bone and tooth development directly or through a RUNX2 signaling pathway related to OSX 32. COL-I comprises almost 90% of organic material during the formation of inorganic bone matrix to support the structure of osteogenesis333536. OCN is a small c-carboxyglutamate protein, which is synthesized only by mature cementoblasts, osteoblasts and odontoblasts, and its function is controlled by RUNX2 in the later-stage of mineralized tissues353637.…”

Safety Evaluation of a Bioglass–Polylactic Acid Composite Scaffold Seeded with Progenitor Cells in a Rat Skull Critical-Size Bone Defect

“…They observed no test material-related effects in mortality, inflammation, hematology, serum biochemistry parameters and organ weight in the operated animals at 8, 12, and 24 weeks after implantation [33]. Other scientists have analyzed the biocompatibility of PLA to cells and consistently report good adhesion and no acute cytotoxic effects on fibroblasts [49], MSCs [50], osteoblasts [51] or endothelial cells [52].…”