Department of Orthopedics, Xiangya Hospital, Central South University, No. 87 Xiangya Road, Changsha, Hunan 410008, China.
Department of Orthopedics, Xiangya Hospital, Central South University, No. 87 Xiangya Road, Changsha, Hunan 410008, China; Department of Orthopedics, The Fifth Affiliated Hospital of Xinjiang Medical University, Urumqi, Xinjiang 830011, China.
Injury. 2022 Mar;53(3):868-877. doi: 10.1016/j.injury.2021.11.003. Epub 2021 Nov 6.
The purpose of this study was to determine the effects of polymethylmetnacrylate (PMMA) spacer loaded with different concentrations of vancomycin on the proliferative, osteogenic, and angiogenic capacity of the induced membrane.
Varying concentrations of vancomycin (0, 1, 2, 4, 6, 8, and 10 g) were fully mixed with bone cement powder (40 g), resulting in seven experimental groups. Hollow cylindrical PMMA spacers (10 mm height, 3 mm external diameter, and 0.8 mm internal diameter) were formed by a mold and submerged in phosphate-buffered saline for antibiotic release by spectrophotometry. Eighty-four New Zealand white rabbits were evenly randomized into seven groups, and segmental radius shaft defects (10 mm) were created. Defects were filled with cylindrical PMMA spacers containing different vancomycin concentrations, and subsequently underwent intramedullary fixation with a retrograde Kirschner's wire. Tissue toxicity was assessed and the proliferative, osteogenic, and angiogenic capacity of induced membranes were qualitatively analyzed by immunohistochemistry and real-time PCR.
No obvious toxicity was observed in the animal model. Alizarin red s staining and qualitative detection of type I collagen, CD31, Ki67, and STRO-1 by immunohistochemistry revealed an obvious decrease in the percentage of positively stained cells and in osteogenic capacity when the concentration of vancomycin was more than 6 g per cement dose. Quantitation of gene expression related to osteogenesis (Col1a, Alp, and Runx2), vascularization (Vegf, Tgfb1, and vWF), and proliferation (Oct4 and Stro-1) by real-time PCR revealed slight increases in the expression of selected genes at low vancomycin concentrations (1-4 g per cement dose), and relatively lower gene expression when the concentration of vancomycin was more than 6 g per cement dose.
PMMA spacers loaded with relatively low concentrations of vancomycin (1-4 g per cement dose) did not interfere with the proliferative, osteogenic, and angiogenic capacity of induced membranes, and even promoted their capacity. In contrast, spacers loaded with relatively high concentrations of vancomycin (6-10 g per cement dose) had negative effects on osteoblast viability, angiogenesis, and proliferation.
本研究旨在确定不同浓度万古霉素负载聚甲基丙烯酸甲酯（PMMA）间隔物对诱导膜的增殖、成骨和血管生成能力的影响。
将不同浓度的万古霉素（0、1、2、4、6、8 和 10 g）与骨水泥粉（40 g）充分混合，制成 7 个实验组。通过模具形成空心圆柱形 PMMA 间隔物（10 mm 高，3 mm 外径，0.8 mm 内径），并将其浸入磷酸盐缓冲盐水中，通过分光光度法释放抗生素。84 只新西兰白兔被随机平均分为 7 组，在桡骨干段造成 10 mm 的缺损。用含有不同万古霉素浓度的圆柱形 PMMA 间隔物填充缺损，并随后用逆行克氏针进行髓内固定。通过免疫组织化学和实时 PCR 定性分析组织毒性以及诱导膜的增殖、成骨和血管生成能力。
动物模型中未观察到明显的毒性。茜素红 S 染色和 I 型胶原、CD31、Ki67 和 STRO-1 的免疫组织化学定性检测显示，当万古霉素浓度超过每水泥剂量 6 g 时，阳性染色细胞的百分比和成骨能力明显下降。实时 PCR 定量分析与成骨相关的基因表达（Col1a、Alp 和 Runx2）、血管生成（Vegf、Tgfb1 和 vWF）和增殖（Oct4 和 Stro-1）显示，在低万古霉素浓度（每水泥剂量 1-4 g）时，选择基因的表达略有增加，而当万古霉素浓度超过每水泥剂量 6 g 时，基因表达相对较低。
负载相对较低浓度万古霉素（每水泥剂量 1-4 g）的 PMMA 间隔物不会干扰诱导膜的增殖、成骨和血管生成能力，甚至促进其能力。相比之下，负载相对较高浓度万古霉素（每水泥剂量 6-10 g）的间隔物对成骨细胞活力、血管生成和增殖有负面影响。
