Effect of rhBMP-2 sustained-release nanocapsules on the ectopic osteogenesis process in Sprague-Dawley rats

摘要

Objective:To explore the effect of sustained-release recombinant human bone morphogenetic protein-2(rhBMP-2) on ectopic osteogenesis in the muscle pouches of rats through preparing rhBMP-2 sustained-release capsules by wrapping morphogenesis protein bones-2(BMP-2) using chitosan nanoparticles, and compositing collagen materials.Methods:Twenty fourSprague-Dawley rats were randomly divided into four groups with six rats in each group, that isGroupA (control group),GroupB(only treated with collagen),GroupC(rhBMP-2+collagen treated group) andGroupD(rhBMP-2/cs+collagen treated group).The composite materials for each group were implanted in the bilateral peroneal muscle pouches in rats.The peroneal muscles were only separated without implanting any materials in control group.Rats were sacrificed2 weeks and4 weeks post treatment and samples were cut off for general observation,MicroCT scans and histological observation.Results:General observation showed no new bone formation in GroupsA andB mice, while new bones were formed inGroupsC andD mice.Two weeks after treatmentMicroCT scans showed thatThe bone volume fraction(BVF), trabecular thickness(Tb. Th), bone mineral density(BMD) inGroupC mice were all higher than that inGroupD(P<0.05). At the fourth week, theBVF,Tb.Th andBMD were significantly higher than that at the second week(P<0.01).Conclusions:The slow-release effect of rhBMP-2/cs sustained-release capsules can significantly promote ectopic osteogenesis.Its bone formation effect is better than that of rhBMP-2 burst-release group.