Effects of fibrin-binding oligopeptide on osteopromotion in rabbit calvarial defects

Abstract

PurposeFibronectin (FN) has been shown to stimulate bone regeneration in animal models. The aim of this study was to evaluate the capacity of bovine bone mineral coated with synthetic oligopeptides to enhance bone regeneration in rabbit calvarial defects.MethodsOligopeptides including fibrin-binding sequences of FN repeats were synthesized on the basis of primary and tertiary human plasma FN structures. Peptide coated and uncoated bone minerals were implanted into 10 mm calvarial defects in New Zealand white rabbits, and the animals were sacrificed at 4 or 8 weeks after surgery. After specimens were prepared, histologic examination and histomorphometric analysis were performed.ResultsAt 4 weeks after surgery, the uncoated groups showed a limited amount of osteoid formation at the periphery of the defect and the oligopeptide coated groups showed more osteoid formation and new bone formation in the center of the defect as well as at the periphery. At 8 weeks, both sites showed increased new bone formation. However, the difference between the two sites had reduced.ConclusionsFibrin-binding synthetic oligopeptide derived from FN on deproteinized bovine bone enhanced new bone formation in rabbit calvarial defects at the early healing stage. This result suggests that these oligopeptides can be beneficial in reconstructing oral and maxillofacial deformities or in regenerating osseous bone defects.

Fibronectin and Craniofacial Surgery

“…Surgical implantation of fibrin glue alone in the calvarial defects resulted in new bone formation, but the bone density was significantly greater in the rh BMP-4/fibrin glue group. Similar findings were also reported by Hong et al 74 Lee et al 75 showed that ''bovine bone mineral'' alone will not close 10-mm calvarial defects in rabbits. However, a defect will close if they are treated with ''bovine bone mineral'' coated with fibrin-binding sequence of fibronectin.…”

Fibronectin‐Derived Oligopeptide Stimulates Osteoblast Differentiation Through a Bone Morphogenic Protein 2–Like Signaling Pathway

“…in the current authors' previous studies wherein F20 was identified as being the most effective in inducing osteoblast differentiation. 7,[11][12][13]29 Whereas previous studies by the current authors focused on effect of F20 in osteoblast differentiation, in the present study the molecular mechanism underlying these effects of F20 was investigated.…”

“…As application of the full‐length protein to study motif binding presents considerable limitations, such as instability of the protein through enzymatic cleavage, unexpected effects of other domains, and non‐specific binding to other types of cells, use of a short peptide is recommended 28 . Based on this information, various types of short peptides were tested in the current authors’ previous studies wherein F20 was identified as being the most effective in inducing osteoblast differentiation 7,11‐13,29 . Whereas previous studies by the current authors focused on effect of F20 in osteoblast differentiation, in the present study the molecular mechanism underlying these effects of F20 was investigated.…”

“…In particular, α5β1 selectively binds to the RGD motif in FN located in the 10th FN Type III domain in the presence of a synergistic ProHis‐Ser‐Arg‐Asn (PHSRN) sequence in the 9th FN Type III domain; 6–8 both the RGD and PHSRN sequences are recognized by integrin α5β1 when the optimal spatial conformation exists between these motifs 9 . To better understand the function of the motifs and their intervening sequences, focus has been on analysis of partial FN peptides composed of PHSRN and RGD along with variable amino acids between these motifs indicating optimal conformation 7,10‐14 . Among these, one that includes the 20 amino acids between PHSRN and RGD was selected, termed “F20,” with the sequence PHSRNSITGTNLTPGYTITVYAVTGRGD, because this peptide showed good osteogenic effect.…”

“…9 To better understand the function of the motifs and their intervening sequences, focus has been on analysis of partial FN peptides composed of PHSRN and RGD along with variable amino acids between these motifs indicating optimal conformation. 7,[10][11][12][13][14] Among these, one that includes the 20 amino acids between PHSRN and RGD was selected, termed ''F20,'' with the sequence PHSRNSITGTNLTPGYTITVYAVTGRGD, because this peptide showed good osteogenic effect. In particular, the current authors have previously reported the osteogenic potential of F20 toward differentiation of MG63 7 osteosarcoma and ST2 14 stromal cells, demonstrating stimulation of alkaline phosphatase (ALP) expression using either a recombinant F20 oligopeptide (0.1 mM) 7 purified from an expression vector or a synthetic F20 oligopeptide (1 ng/mL).…”