Lin Jiawei, Qiao Chaofeng, Jiang Hao, Liu Zhihui, Hu Yaxin, Liu Wei, Yong Yu, Li Fenfang
Institute of Biomedical Engineering, Shenzhen Bay Laboratory, Shenzhen, China.
School of Biomedical Engineering, Shenzhen University, Shenzhen, China.
Ultrason Sonochem. 2025 Jan;112:107181. doi: 10.1016/j.ultsonch.2024.107181. Epub 2024 Dec 2.
Ultrasound and microbubble mediated blood brain barrier opening is a non-invasive and effective technique for drug delivery to targeted brain region. However, the exact mechanisms are not fully resolved. The influences of Ca signaling on sonoporation and endothelial tight junctional regulation affect the efficiency and biosafety of the technique. Therefore, an improved understanding of how ultrasound evokes Ca signaling in the brain endothelial monolayer, and its correlation to endothelial permeability change is necessary. Here, we examined the effects of SonoVue microbubbles or integrin-targeted microbeads on ultrasound induced bioeffects in brain microvascular endothelial monolayer using an acoustically-coupled microscopy system, where focused ultrasound exposure and real-time recording of Ca signaling and membrane perforation were performed. Microbubbles induced robust Ca responses, often accompanied by cell poration, while ultrasound with microbeads elicited reversible Ca response without membrane poration. At the conditions evoking reversible Ca signaling, intracellular Ca release and reactive oxygen species played key roles for microbubbles induced Ca signaling while activation of mechanosensitive ion channels was essential for the case of microbeads. Trans-well diffusion analysis revealed significantly higher trans-endothelial transport of 70 kDa FITC-dextran for both integrin-targeted microbeads and microbubbles compared to the control group. Further immunofluorescence staining showed disruption of cell junctions with microbubble stimulation and reversible remodeling of many cell junctions by ultrasound with integrin-targeted microbeads. This investigation provides new insights for ultrasound induced Ca signaling and its influence on endothelial permeability, which may help develop new strategies for safe and efficient drug/gene delivery in the vascular system.
超声与微泡介导的血脑屏障开放是一种将药物递送至脑靶向区域的非侵入性有效技术。然而，其确切机制尚未完全明确。钙信号对声孔效应和内皮紧密连接调节的影响关乎该技术的效率和生物安全性。因此，有必要进一步了解超声如何在脑内皮单层细胞中引发钙信号，以及其与内皮通透性变化的相关性。在此，我们使用声学耦合显微镜系统，研究了声诺维微泡或整合素靶向微珠对超声诱导的脑微血管内皮单层细胞生物效应的影响，该系统可进行聚焦超声照射以及钙信号和膜穿孔的实时记录。微泡可诱导强烈的钙反应，常伴有细胞穿孔，而超声联合微珠则引发可逆的钙反应且无膜穿孔。在引发可逆钙信号的条件下，细胞内钙释放和活性氧物种在微泡诱导的钙信号中起关键作用，而机械敏感离子通道的激活对微珠情况至关重要。跨膜扩散分析显示，与对照组相比，整合素靶向微珠和微泡组中70 kDa异硫氰酸荧光素标记的葡聚糖的跨内皮转运显著更高。进一步的免疫荧光染色显示，微泡刺激会破坏细胞连接，而超声联合整合素靶向微珠会使许多细胞连接发生可逆重塑。本研究为超声诱导的钙信号及其对内皮通透性的影响提供了新见解，这可能有助于开发血管系统中安全有效的药物/基因递送新策略。
