RESUMO
To experimentally evaluate the ectopic osteogenetic capacity of synthesized BMP2-derived peptide P24 combined with poly lactic-co-glycolic acid (PLGA), Wistar rats were divided into two groups: group A, in which BMP2-derived peptide P24/PLGA complex was implanted,and group B which received simple PLGA implant. The complex was respectively implanted into the back muscles of rats. Samples were taken the 1 st, 4 th, 8 th, and the 12 th week after the implantation.Their bone formation was detected by X-ray examination, and tissue response was histologically observed. Western blotting was used for the detection of the expression of collagen Ⅰ (Col- Ⅰ ) and osteopontin (OPN). There was acute inflammation in the tissue around both types of implants at early stage. The cartilage was found around implant areas 4 weeks after the implantation of BMP2-derived peptide p24/PLGA complex, 8 weeks after the implantation, osteoblasts were found, and 12 weeks after the implantation, typical trabecular bone structure was observed. In group B, after 12 weeks, no osteoblasts were found. It is concluded that PLGA is an ideal scaffold material for bone tissue engineering. BMP2-derived peptide can start endochondral ossification and is more effective in inducing ectopic osteogenesis.
RESUMO
[Objective]To investigate the capability of synthesis BMP-2-derived peptide on osteogenic induction in bone marrow stem cells(BMSEs),and to evaluate the osteoinductivity of BMP-2-derived peptide in vitro.[Method]After segregating and cultivating four weeks Wistar rats marrow stromal cells in induction group were induced by osteogenasis medium containing 200 gg/ml BMP-2-derived peptide,and in non-inductional group BMSCs were still culture with DMEM medium.Following continue culture for 2~4 weeks,cells film preparation,alkaline phosphatase activity and calcium deposition were measured.Type I collagen(CoM)and osteopontin(OPN)mRNA expression were measured using real-time fluorescent quantitative polymerase chain reaction(FQ-PCR)technique.The capability of synthesis BMP-2-derived peptide on osteogenic induction of BMSCs was investigated.[Result]After inductived with BMP-2-derived peptide.BMSCs cultured survived well greatly changed in cell morphology,and showed a biological and morphologie characteristics similar to those of osteoblasts.The lever of alkaline phosphatase activity and calcium deposition increased.Col-Ⅰand OPN mRNA were expressed at higher level.In non-inductional group no conspicuous osteogenic induction was shown.[Conclusion]BMP-2-derived peptide can induce BMSCs to differentiate into osteoblasts.It has the similar capacity of osteogenic induction as nature BMP-2,so BMP-2-derived peptide is an ideal cell agent for bone tissue engineering,and can be available widely.