Extracellular matrix (ECM) materials, known for their excellent biocompatibility and bioactivity, have been widely applied in the repair of various tissues and organs. However, due to challenges such as rapid degradation, insufficient mechanical properties, and the lack of immunomodulatory and osteoinductive functions, these materials are not yet fully suitable for bone tissue regeneration. In this study, we firstly modified a porcine small intestinal submucosa (SIS) by methacrylating it through Michael addition to create a novel methacrylated SIS (SM), and further functionalized it with a metal-phenolic supramolecular network self-assembled from magnesium ions (Mg²⁺) and epigallocatechin gallate (EGCG), aiming to enhance its physicochemical properties and impart biological functions. Results showed that the Mg-EGCG modified SM (Mg₃E₁@SM) demonstrated significantly prolonged degradation performance and enhanced mechanical properties. Besides, it could effectively facilitate the polarization of macrophages from the M1 to M2 phenotype, promoted angiogenesis, and enhanced stem cell osteogenic differentiation and biomineralization, thereby substantially accelerating bone defect repair. In summary, this study presents a simple and effective strategy to enhance the performance of ECM-based biomaterials, broadening their application in the repair of bone and other hard tissues.

中文翻译：

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Mg-EGCG 改性多功能甲基丙烯酸化小肠粘膜下层支架增强骨再生

细胞外基质 （ECM） 材料以其优异的生物相容性和生物活性而闻名，已广泛应用于各种组织器官的修复。然而，由于快速降解、机械性能不足以及缺乏免疫调节和骨诱导功能等挑战，这些材料尚不完全适合骨组织再生。在本研究中，我们首先通过迈克尔加成对猪小肠粘膜下层 （SIS） 进行甲基丙烯酸化修饰，制备了新型甲基丙烯酸化 SIS （SM），并进一步用镁离子 （Mg²⁺） 和表没食子儿茶素没食子酸酯 （EGCG） 自组装的金属酚类超分子网络对其进行功能化，旨在增强其理化性质并赋予生物学功能。结果表明，Mg-EGCG 改性的 SM （Mg₃E₁@SM） 表现出显著延长的降解性能和增强的机械性能。此外，它可以有效地促进巨噬细胞从 M1 表型极化到 M2 表型，促进血管生成，增强干细胞成骨分化和生物矿化，从而大大加速骨缺损修复。总之，本研究提出了一种简单有效的策略来提高基于 ECM 的生物材料的性能，拓宽它们在骨骼和其他硬组织修复中的应用。