RESUMEN
Enhancement of osteogenic capacity was achieved in a mineralized collagen composite, nano-hydroxyapatite/collagen (nHAC), by loading with synthetic peptides derived from BMP-2 residues 32-48 (P17-BMP-2). Rabbit marrow stromal cells (MSCs) were used in vitro to study cell biocompatibility, attachment and differentiation on the mineralized collagen composite by a cell counting kit, scanning electron microscopy (SEM) and real-time reversed transcriptase-polymerase chain reaction analysis (RT-PCR). Optimal peptide dosage (1.0 µg/mL) was obtained by RT-PCR analysis in vitro. In addition, the relative expression level of OPN and OCN was significantly upregulated on P17-BMP-2/nHAC compared with nHAC. In vitro results of P17-BMP-2 release kinetics demonstrated that nHAC released P17-BMP-2 in a controlled and sustained manner. In the rabbit mandibular box-shaped bone defect model, osteogenic capacity of three groups (nHAC, P17-BMP-2/nHAC, rhBMP-2/nHAC) was evaluated. Compared to the nHAC group, bone repair responses in both P17-BMP-2/nHAC and rhBMP-2/nHAC group implants were significantly improved based on histological analysis. The osteogenic response of the P17-BMP-2/nHAC group was similar to that of the rhBMP-2/nHAC group.
Asunto(s)
Proteína Morfogenética Ósea 2/farmacología , Materiales Biocompatibles Revestidos/farmacología , Colágeno/farmacología , Durapatita/farmacología , Minerales/farmacología , Osteogénesis/efectos de los fármacos , Péptidos/farmacología , Factor de Crecimiento Transformador beta/farmacología , Animales , Adhesión Celular/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Células Cultivadas , Cromatografía Líquida de Alta Presión , Cinética , Osteoblastos/citología , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Conejos , Proteínas Recombinantes/farmacologíaRESUMEN
In this study, the biocompatibility and bone regeneration performance of nano-hydroxyapatite/collagen/poly(L-lactide) (nHAC/PLA) and nano-hydroxyapatite/collagen/calcium sulfate hemihydrate (nHAC/CSH) as bone-filling materials were evaluated and compared in a critical box-shaped defect model in the mandible of the rabbits. In vivo results indicated that there was significant difference in early bone remodeling between two types of bone substitutes. nHAC/PLA has shown excellent biocompatibility, but no adequate handling properties. The addition of CSH to nHAC provided better manipulability compared to nHAC/PLA. Furthermore, nHAC/CSH possesses superior properties in restoring critical-sized bone defects of maxillofacial region at the early stage of remodeling over nHAC/PLA. Our results suggested that nHAC/CSH could be an alternative to the conventionally used bone tissue engineering materials.
Asunto(s)
Sustitutos de Huesos/química , Trasplante Óseo/métodos , Osteogénesis , Animales , Regeneración Ósea , Calcificación Fisiológica , Sulfato de Calcio , Colágeno , Durapatita , Masculino , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Nanoestructuras/química , Nanoestructuras/ultraestructura , Poliésteres , Conejos , Ingeniería de Tejidos , Difracción de Rayos XRESUMEN
Comparative investigations of bone regeneration performance for calcium sulfate hemihydrate (CaSO(4).(1/2)H(2)O; CSH) only and CSH with mineralized collagen are reported in this article. The mineralized collagen is the nanohydroxyapatite/collagen (nHAC). The investigations included biocompatibility in vitro and performance of bone repair in vivo. Quantitative and qualitative biocompatibility assays with bone stromal stem cells were performed. A critical box-shaped defect model in the mandible of the rabbit was used to evaluate the bone-remodeling ability of CSH and nHAC/CSH. Results in vitro indicated that the nHAC/CSH significantly improved bioactivity compared with that of CSH, especially in promoting cell adhesion. Further, a higher bone remodeling activity was observed around nHAC/CSH composite than the CSH, especially at the early stage of remodeling. This result means that nHAC/CSH could cause an earlier accelerator and better osseointegration for bone repair than CSH only.
Asunto(s)
Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Remodelación Ósea/efectos de los fármacos , Sulfato de Calcio/química , Sulfato de Calcio/farmacología , Colágeno/química , Colágeno/farmacología , Durapatita/química , Durapatita/farmacología , Animales , Apoptosis/efectos de los fármacos , Células de la Médula Ósea/citología , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/metabolismo , Adhesión Celular/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Microscopía Electrónica de Rastreo , Oseointegración/efectos de los fármacos , Conejos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células del Estroma/citología , Células del Estroma/efectos de los fármacos , Células del Estroma/metabolismoRESUMEN
A novel injectable bone cement based on mineralized collagen was reported in this paper. The cement was fabricated by introducing calcium sulfate hemihydrate (CaSO(4).1/2H(2)O, CSH) into nano-hydroxyapatite/collagen (nHAC). The workability, in vitro degradation, in vitro and in vivo biocompatibility of the cement (nHAC/CSH) were studied. The comparative tests via in vitro and in vivo showed that the nHAC/CSH composite cement processed better biocompatibiltiy than that of pure CSH cement. The results implied that this new injectable cement should be very promising for bone repair.