Local oxidative stress in diseases or injury severely hinders cell homeostasis and organ regeneration. Antioxidant therapy is an effective strategy for oxidative stress treatment. Biomaterials with good biocompatibility and reactive oxygen species (ROS) scavenging ability are good choices for antioxidant therapeutics. However, there are few natural biomaterials that are identified with both biocompatibility and strong antioxidant activity. Here, we show, for the first time, that silk fibroin (SF) is a strong antioxidant, which can eliminate ROS in both cells and zebrafish. We further demonstrate that the β-sheet structures turn into a random coiled structure when SF is treated with hydrogen peroxide. The content of β-sheet structures can be increased by heating, thus enhancing the antioxidation properties of SF. Therefore, SF can serve as a good antioxidant biomaterial for therapeutics, and its β-sheet structure-based antioxidation mechanism provides a novel theoretical basis, which could be a new cue for more antioxidant biomaterial discovery and identification.

中文翻译：

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揭示丝素蛋白中自组装β-片层的抗氧化行为


疾病或损伤中的局部氧化应激严重阻碍细胞稳态和器官再生。抗氧化治疗是氧化应激治疗的有效策略。具有良好生物相容性和活性氧（ROS）清除能力的生物材料是抗氧化治疗的良好选择。然而，同时具有生物相容性和强抗氧化活性的天然生物材料很少。在这里，我们首次证明丝素蛋白（SF）是一种强抗氧化剂，可以消除细胞和斑马鱼中的ROS。我们进一步证明，当 SF 用过氧化氢处理时，β-折叠结构会变成随机卷曲结构。通过加热可以增加β-折叠结构的含量，从而增强SF的抗氧化性能。因此，SF可以作为一种良好的抗氧化生物材料用于治疗，其基于β-折叠结构的抗氧化机制提供了新的理论基础，这可能为更多抗氧化生物材料的发现和鉴定提供新的线索。