Zhan Jianfeng, Liu Xumei, Yu Bo
Department of Orthopedics & Traumatology, Zhujiang Hospital of Southern Medical University, Guangzhou Guangdong, 510282, P.R.China.
Department of Ultrasonic Diagnosis, Zhujiang Hospital of Southern Medical University, Guangzhou Guangdong, 510282, P.R.China.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2018 Sep 15;32(9):1144-1149. doi: 10.7507/1002-1892.201806086.
To study the ectopic osteogenesis and biocompatibility of bone morphogenetic protein 2 (BMP-2)-derived peptide P24 loaded chitosan-4-thio-butylamidine (CS-TBA) hydrogel.
First, the CS-TBA/hydroxyapatite (HA) solution was prepared by using chitosan, 2-iminothiolane hydrochloride, and HA. Then, the different amount of P24 peptides were added to the CS-TBA/HA to prepare the CS-TBA/5%P24/HA and CS-TBA/10%P24/HA solutions. Finally, β-glycerophosphate disodium (β-GP) was added to the CS-TBA/HA, CS-TBA/5%P24/HA, and CS-TBA/10%P24/HA to prepare the CS-TBA/HA/β-GP, CS-TBA/5%P24/HA/β-GP, and CS-TBA/10%P24/HA/β-GP hydrogels, respectively. Eighteen Sprague Dawley female rats were randomly divided into 3 groups ( =6), which were injected into the back muscle pouches with equal volume CS-TBA/HA/β-GP hydrogel (group A), CS-TBA/5%P24/HA/β-GP hydrogel (group B), and CS-TBA/10%P24/HA/β-GP hydrogel (group C). The animals were sacrificed at 4 and 8 weeks and conducted micro-CT. The ability of biodegradation and osteogenesis of hydrogl was detected by trabecular thickness (Tb.Th), trabecular number (Tb.N), bone mineral density (BMD), and histological staining (HE and Masson).
All the rats in 3 groups survived to the time point of the harvest. Micro-CT results showed that the new bones gradually increased in each group after operation. At the same time, the new bone formation was more obvious in groups B and C than in group A, and with the increase of P24 concentration, new bone formation in group C was much more than that in group B. The Tb.Th, Tb.N, and BMD increased gradually in 3 groups, and the differences between 4 and 8 weeks were significant ( <0.05) except the Tb.Th in group A. At different time points, the Tb.Th, Tb.N, and BMD were significantly higher in groups B and C than in group A ( <0.05), and in group C was higher than in group B ( <0.05), showing significant differences between groups. Histological staining showed that the materials of groups B and C were biodegradable, and the osteogenic effect was increased with the increase of P24 concentration.
P24 peptide can improve the ectopic osteogenesis of CS-TBA hydrogel, and the 10% concentration is more effective.
研究负载骨形态发生蛋白2（BMP-2）衍生肽P24的壳聚糖-4-硫代丁脒（CS-TBA）水凝胶的异位成骨及生物相容性。
首先，用壳聚糖、盐酸2-亚氨基硫醇和羟基磷灰石（HA）制备CS-TBA/羟基磷灰石（HA）溶液。然后，向CS-TBA/HA中加入不同量的P24肽，制备CS-TBA/5%P24/HA和CS-TBA/10%P24/HA溶液。最后，向CS-TBA/HA、CS-TBA/5%P24/HA和CS-TBA/10%P24/HA中加入β-甘油磷酸二钠（β-GP），分别制备CS-TBA/HA/β-GP、CS-TBA/5%P24/HA/β-GP和CS-TBA/10%P24/HA/β-GP水凝胶。将18只雌性Sprague Dawley大鼠随机分为3组（每组n = 6），分别向背部肌肉袋中注射等体积的CS-TBA/HA/β-GP水凝胶（A组）、CS-TBA/5%P24/HA/β-GP水凝胶（B组）和CS-TBA/10%P24/HA/β-GP水凝胶（C组）。在4周和8周时处死动物并进行显微CT检查。通过骨小梁厚度（Tb.Th）、骨小梁数量（Tb.N）、骨密度（BMD）和组织学染色（HE和Masson）检测水凝胶的生物降解和成骨能力。
3组所有大鼠均存活至取材时间点。显微CT结果显示，术后各组新骨逐渐增多。同时，B组和C组的新骨形成比A组更明显，且随着P24浓度的增加，C组的新骨形成明显多于B组。3组的Tb.Th、Tb.N和BMD逐渐增加，除A组的Tb.Th外，4周和8周之间的差异有统计学意义（P < 0.05）。在不同时间点，B组和C组的Tb.Th、Tb.N和BMD均显著高于A组（P < 0.05），且C组高于B组（P < 0.05），组间差异显著。组织学染色显示，B组和C组的材料可生物降解，且成骨作用随P24浓度增加而增强。
P24肽可改善CS-TBA水凝胶的异位成骨，10%浓度效果更佳。
