Department of Trauma, Hand and Reconstructive Surgery, University Hospital, Goethe University Frankfurt, 60590 Frankfurt am Main, Germany.
Vascular Research Centre, Goethe University Frankfurt, 60590 Frankfurt am Main, Germany.
Cells. 2023 Aug 26;12(17):2151. doi: 10.3390/cells12172151.
Electrical stimulation (EStim), whether used alone or in combination with bone tissue engineering (BTE) approaches, has been shown to promote bone healing. In our previous in vitro studies, mesenchymal stem cells (MSCs) were exposed to EStim and a sustained, long-lasting increase in osteogenic activity was observed. Based on these findings, we hypothesized that pretreating MSC with EStim, in 2D or 3D cultures, before using them to treat large bone defects would improve BTE treatments. Critical size femur defects were created in 120 Sprague-Dawley rats and treated with scaffold granules seeded with MSCs that were pre-exposed or not (control group) to EStim 1 h/day for 7 days in 2D (MSCs alone) or 3D culture (MSCs + scaffolds). Bone healing was assessed at 1, 4, and 8 weeks post-surgery. In all groups, the percentage of new bone increased, while fibrous tissue and CD68+ cell count decreased over time. However, these and other healing features, like mineral density, bending stiffness, the amount of new bone and cartilage, and the gene expression of osteogenic markers, did not significantly differ between groups. Based on these findings, it appears that the bone healing environment could counteract the long-term, pro-osteogenic effects of EStim seen in our in vitro studies. Thus, EStim seems to be more effective when administered directly and continuously at the defect site during bone healing, as indicated by our previous studies.
电刺激（EStim），无论是单独使用还是与骨组织工程（BTE）方法结合使用，都已被证明可以促进骨愈合。在我们之前的体外研究中，间充质干细胞（MSCs）暴露于 EStim 中，观察到成骨活性持续、持久增加。基于这些发现，我们假设在使用它们治疗大的骨缺损之前，通过 2D 或 3D 培养物预先用 EStim 预处理 MSC，将改善 BTE 治疗。在 120 只 Sprague-Dawley 大鼠中创建临界大小股骨缺损，并使用预先暴露或未暴露（对照组）于 EStim 的支架颗粒治疗，每天 1 小时，持续 7 天，在 2D（MSC 单独）或 3D 培养（MSC+支架）中。在手术后 1、4 和 8 周评估骨愈合情况。在所有组中，随着时间的推移，新骨的百分比增加，而纤维组织和 CD68+细胞计数减少。然而，这些和其他愈合特征，如矿物质密度、弯曲刚度、新骨和软骨的量以及成骨标志物的基因表达，在组间没有显著差异。基于这些发现，似乎骨愈合环境可以抵消我们在体外研究中观察到的 EStim 的长期促成骨作用。因此，正如我们之前的研究所示，EStim 在骨愈合过程中直接并持续地施用于缺损部位时似乎更有效。
