Critical-sized bone defects caused by traumatic fractures, tumour resection and congenital malformation are unlikely to heal spontaneously. Bone tissue engineering is a promising strategy aimed at developing in vitro replacements for bone transplantation and overcoming the limitations of natural bone grafts. In this study, we developed an innovative bone engineering scaffold based on gelatin methacrylate (GelMA) hydrogel, obtained via a two-step procedure: first, solid lipid nanoparticles (SLNs) were loaded with resveratrol (Res), a drug that can promote osteogenic differentiation and bone formation; these particles were then encapsulated at different concentrations (0.01%, 0.02%, 0.04% and 0.08%) in GelMA to obtain the final Res-SLNs/GelMA scaffolds. The effects of these scaffolds on osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and bone regeneration in rat cranial defects were evaluated using various characterization assays. Our in vitro and in vivo investigations demonstrated that the different Res-SLNs/GelMA scaffolds improved the osteogenic differentiation of BMSCs, with the ideally slow and steady release of Res; the optimal scaffold was 0.02 Res-SLNs/GelMA. Therefore, the 0.02 Res-SLNs/GelMA hydrogel is an appropriate release system for Res with good biocompatibility, osteoconduction and osteoinduction, thereby showing potential for application in bone tissue engineering.

中文翻译：

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载有白藜芦醇的固体脂质纳米粒的甲基丙烯酸明胶水凝胶支架用于增强骨髓间充质干细胞的成骨分化和有效的骨再生

由外伤性骨折、肿瘤切除和先天性畸形引起的临界大小的骨缺损不太可能自愈。骨组织工程是一种很有前景的策略，旨在开发用于骨移植的体外替代物并克服天然骨移植物的局限性。在这项研究中，我们开发了一种基于甲基丙烯酸明胶 (GelMA) 水凝胶的创新骨工程支架，该支架通过两步程序获得：首先，固体脂质纳米颗粒 (SLN) 负载白藜芦醇 (Res)，一种可以促进成骨的药物分化和骨形成；然后将这些颗粒以不同浓度（0.01%、0.02%、0.04% 和 0.08%）封装在 GelMA 中，以获得最终的 Res-SLNs/GelMA 支架。这些支架对骨髓间充质干细胞 (BMSCs) 的成骨分化和大鼠颅骨缺损中骨再生的影响使用各种表征分析进行了评估。我们的体外和体内研究表明，不同的 Res-SLNs/GelMA 支架改善了 BMSCs 的成骨分化，理想的 Res 释放缓慢而稳定；最佳支架为 0.02 Res-SLNs/GelMA。因此，0.02 Res-SLNs/GelMA水凝胶是一种合适的Res释放系统，具有良好的生物相容性、骨传导和骨诱导，从而显示出在骨组织工程中的应用潜力。我们的体外和体内研究表明，不同的 Res-SLNs/GelMA 支架改善了 BMSCs 的成骨分化，理想的 Res 释放缓慢而稳定；最佳支架为 0.02 Res-SLNs/GelMA。因此，0.02 Res-SLNs/GelMA水凝胶是一种合适的Res释放系统，具有良好的生物相容性、骨传导和骨诱导，从而显示出在骨组织工程中的应用潜力。我们的体外和体内研究表明，不同的 Res-SLNs/GelMA 支架改善了 BMSCs 的成骨分化，理想的 Res 释放缓慢而稳定；最佳支架为 0.02 Res-SLNs/GelMA。因此，0.02 Res-SLNs/GelMA水凝胶是一种合适的Res释放系统，具有良好的生物相容性、骨传导和骨诱导，从而显示出在骨组织工程中的应用潜力。