Zheng Houwei, Jia Fan, Gao Ying, Deng Kaicheng, Shen Liyin, Zheng Chao, Xie Xin, Gao Changyou, Ren Tanchen, Zhu Yang
MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310058, Zhejiang, China.
Department of Cardiology, Sir Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310016, Zhejiang, China.
Acta Biomater. 2025 Aug 22. doi: 10.1016/j.actbio.2025.08.040.
Nitric oxide (NO) can alleviate cardiac ischemia/reperfusion injury with its anti-inflammatory, antioxidant, and angiogenic effects. However, local NO availability is limited due to its short half-life, reduced production, and consumption by excess reactive oxygen species (ROS) generated in injured myocardium. Here, we designed an injectable hydrogel microsphere system (WPI-H-N) based on acrylated whey protein (WPI), onto which phenylborate ester group was attached and served as a ROS-cleavable linker for 5-isosorbide mononitrate (ISMN), a NO donor. This injectable hydrogel microsphere system was designed to scavenge excess ROS, and release NO in response to oxidative stress in the niche in order to achieve on-demand NO release, reduce NO depletion by ROS, and prolong NO retention in the infarcted myocardium. In a rat I/R model, WPI-H-N protected cardiomyocytes from apoptosis, attenuated cardiac oxidative injury and improved angiogenesis in the infarcted myocardium. These results demonstrate that the combination of ROS scavenging and responsive NO release can simultaneously overcome the two major limitations of NO therapy, supporting the development of more efficient NO delivery strategies. STATEMENT OF SIGNIFICANCE: This study presents an injectable hydrogel microsphere system that synergistically scavenges reactive oxygen species (ROS) and enables on-demand nitric oxide (NO) release for cardiac protection against ischemia/reperfusion injury. Unlike existing NO delivery platforms, the ROS-responsive phenylborate ester linkage ensures spatiotemporally controlled NO release, minimizing premature consumption by ROS and secondary nitrosative stress. The microspheres' dual functionality-simultaneously neutralizing oxidative stress and promoting angiogenesis-addresses critical limitations of conventional NO therapies. In vivo results demonstrate significant reductions in cardiomyocyte apoptosis, oxidative damage, and infarct size, alongside improved cardiac function and vascularization. This strategy offers a potentially translatable approach for local and controlled NO release to achieve cardiac repair. The work holds broad implications for ROS-related pathologies and precision therapeutic delivery in regenerative medicine.
一氧化氮（NO）具有抗炎、抗氧化和血管生成作用，可减轻心脏缺血/再灌注损伤。然而，由于其半衰期短、生成减少以及受损心肌中产生的过量活性氧（ROS）对其消耗，局部NO的可用性有限。在此，我们设计了一种基于丙烯酸化乳清蛋白（WPI）的可注射水凝胶微球系统（WPI-H-N），其上连接了苯硼酸酯基团，并作为NO供体5-单硝酸异山梨酯（ISMN）的ROS可裂解连接体。该可注射水凝胶微球系统旨在清除过量的ROS，并响应微环境中的氧化应激释放NO，以实现按需释放NO、减少ROS对NO的消耗以及延长NO在梗死心肌中的保留时间。在大鼠缺血/再灌注模型中，WPI-H-N保护心肌细胞免于凋亡，减轻心脏氧化损伤并改善梗死心肌中的血管生成。这些结果表明，ROS清除和响应性NO释放的结合可以同时克服NO治疗的两个主要局限性，支持开发更有效的NO递送策略。重要性声明：本研究提出了一种可注射水凝胶微球系统，该系统协同清除活性氧（ROS）并实现按需释放一氧化氮（NO）以保护心脏免受缺血/再灌注损伤。与现有的NO递送平台不同，ROS响应性苯硼酸酯连接确保了时空控制的NO释放，最大限度地减少了ROS的过早消耗和继发性亚硝化应激。微球的双重功能——同时中和氧化应激和促进血管生成——解决了传统NO疗法的关键局限性。体内结果表明，心肌细胞凋亡、氧化损伤和梗死面积显著减少，同时心脏功能和血管化得到改善。该策略为局部和可控的NO释放以实现心脏修复提供了一种潜在的可转化方法。这项工作对ROS相关疾病和再生医学中的精准治疗递送具有广泛的意义。
