Ray Seemun, Thormann Ulrich, Kramer Inga, Sommer Ursula, Budak Matthäus, Schumacher Matthias, Bernhardt Anne, Lode Anja, Kern Christine, Rohnke Marcus, Heiss Christian, Lips Katrin S, Gelinsky Michael, Alt Volker
Laboratory of Experimental Trauma Surgery, Justus Liebig University, 35390 Giessen, Germany.
Department of Trauma Surgery, University Hospital Giessen-Marburg GmbH, Campus Giessen, 35390 Giessen, Germany.
Bioengineering (Basel). 2023 Oct 16;10(10):1203. doi: 10.3390/bioengineering10101203.
In this study, the in vitro and in vivo bone formation behavior of mesoporous bioactive glass (MBG) particles incorporated in a pasty strontium-containing calcium phosphate bone cement (pS100G10) was studied in a metaphyseal fracture-defect model in ovariectomized rats and compared to a plain pasty strontium-containing calcium phosphate bone cement (pS100) and control (empty defect) group, respectively. In vitro testing showed good cytocompatibility on human preosteoblasts and ongoing dissolution of the MBG component. Neither the released strontium nor the BMG particles from the pS100G10 had a negative influence on cell viability. Forty-five female Sprague-Dawley rats were randomly assigned to three different treatment groups: (1) pS100 ( = 15), (2) pS100G10 ( = 15), and (3) empty defect ( = 15). Twelve weeks after bilateral ovariectomy and multi-deficient diet, a 4 mm wedge-shaped fracture-defect was created at the metaphyseal area of the left femur in all animals. The originated fracture-defect was substituted with pS100 or pS100G10 or left empty. After six weeks, histomorphometrical analysis revealed a statistically significant higher bone volume/tissue volume ratio in the pS100G10 group compared to the pS100 ( = 0.03) and empty defect groups ( = 0.0001), indicating enhanced osteoconductivity with the incorporation of MBG. Immunohistochemistry revealed a significant decrease in the RANKL/OPG ratio for pS100 ( = 0.004) and pS100G10 ( = 0.003) compared to the empty defect group. pS100G10 showed a statistically higher expression of BMP-2. In addition, a statistically significant higher gene expression of alkaline phosphatase, osteoprotegerin, collagen1a1, collagen10a1 with a simultaneous decrease in RANKL, and carbonic anhydrase was seen in the pS100 and pS100G10 groups compared to the empty defect group. Mass spectrometric imaging by time-of-flight secondary ion mass spectrometry (ToF-SIMS) showed the release of Sr ions from both pS100 and pS100G10, with a gradient into the interface region. ToF-SIMS imaging also revealed that resorption of the MBG particles allowed for new bone formation in cement pores. In summary, the current work shows better bone formation of the injectable pasty strontium-containing calcium phosphate bone cement with incorporated mesoporous bioactive glass compared to the bioactive-free bone cement and empty defects and can be considered for clinical application for osteopenic fracture defects in the future.
在本研究中，在去卵巢大鼠的干骺端骨折缺损模型中，研究了掺入含锶糊状磷酸钙骨水泥（pS100G10）中的介孔生物活性玻璃（MBG）颗粒的体外和体内骨形成行为，并分别与普通含锶糊状磷酸钙骨水泥（pS100）和对照组（空白缺损）进行比较。体外测试显示，MBG成分对人成骨前体细胞具有良好的细胞相容性且持续溶解。从pS100G10释放的锶和BMG颗粒均对细胞活力无负面影响。45只雌性Sprague-Dawley大鼠被随机分为三个不同的治疗组：（1）pS100（n = 15），（2）pS100G10（n = 15），和（3）空白缺损（n = 15）。在双侧卵巢切除和多缺乏饮食12周后，在所有动物的左股骨干骺端区域制造一个4毫米楔形骨折缺损。将产生的骨折缺损用pS100或pS100G10替代或留空。六周后，组织形态计量学分析显示，与pS100组（P = 0.03）和空白缺损组（P = 0.0001）相比，pS100G10组的骨体积/组织体积比在统计学上显著更高，表明掺入MBG可增强骨传导性。免疫组织化学显示，与空白缺损组相比，pS100组（P = 0.004）和pS100G10组（P = 0.003）的RANKL/OPG比值显著降低。pS100G10显示出BMP-2的统计学上更高的表达。此外，与空白缺损组相比，pS100组和pS100G10组中碱性磷酸酶、骨保护素、胶原蛋白1a1、胶原蛋白10a1的基因表达在统计学上显著更高，同时RANKL和碳酸酐酶降低。通过飞行时间二次离子质谱（ToF-SIMS）进行的质谱成像显示，pS100和pS100G10均释放Sr离子，并向界面区域呈梯度分布。ToF-SIMS成像还显示，MBG颗粒的吸收允许在骨水泥孔隙中形成新骨。总之，目前的工作表明，与无生物活性的骨水泥和空白缺损相比，掺入介孔生物活性玻璃的可注射含锶糊状磷酸钙骨水泥具有更好的骨形成效果，未来可考虑用于骨质疏松性骨折缺损的临床应用。
