声动力治疗通过线粒体VDAC1寡聚化促进细胞色素C释放使巨噬细胞凋亡从而缩小稳定动脉粥样硬化斑块

So far, the strategy that aims to attenuate inflammation within atherosclerotic plaque, and thus reduce and stabilize the plaque, is limited. Our former research demonstrated: (ⅰ) Sonodynamic therapy (SDT) could alleviate the inflammation within atherosclerotic plaque, and also reduce and stabilize the plaque. (ⅱ) SDT could induce macrophage apoptosis in the plaque, and facilitate the recruitment, phagocytosis and migration of monocyte/macrophage. (ⅲ) SDT could promote cytochrome c (Cyt-C) release from the mitochondria of macrophages, and activate mitochondrion-dependent apoptosis pathway of macrophages. However, the mechanism for Cyt-C release remains unknown. Thus，we propose that SDT activates protoporphyrin IX binding to the 18 kD translocator protein of the mitochondria, and produces reactive oxygen species, which induce disulfide bond-mediated oligomerization of the mitochondria voltage-dependent anion channel-1(VDAC1) via oxidizing cysteine residues of neighbouring VDAC1, and eventually promotes Cyt-C release. We have developed SDT equipments for experiments of cells and mice. Applying human acute monocytic leukemia cell line (THP-1) and apolipoprotein E knockout (apoE-/-) mice model, we are going to use small interfering RNA, atomic force microscope, cryomicroscope and so on to verify our hypothesis. This is an interdisciplinary research project with important theoretical significance, broad clinical value and industrialization prospect.

目前尚无减轻动脉粥样硬化（AS）斑块炎症并使斑块稳定、缩小的有效方法。我们前期研究发现：声动力治疗（SDT）能减小、稳定AS斑块并减轻斑块炎症；诱导斑块巨噬细胞凋亡，促进单核-巨噬细胞的趋化、吞噬及迁移；促进巨噬细胞线粒体细胞色素C（Cyt-C）释放激活线粒体依赖性凋亡途径。但SDT如何诱导巨噬细胞线粒体释放Cyt-C尚不明确。我们提出设想：SDT作用于AS斑块巨噬细胞，激活结合在线粒体18kD转运蛋白（TSPO）上的原卟啉IX（PpIX）,产生活性氧，氧化相邻电压依赖性阴离子通道1（VDAC1）的半胱氨酸形成二硫键，使VDAC1寡聚化形成足够大的孔道，使Cyt-C释放。拟用已研发的细胞及小鼠SDT装置，应用线粒体、THP-1巨噬细胞及apoE-/-小鼠模型，采用siRNA干扰、原子力显微镜及冰冻电子显微镜等证实上述设想。本项目为交叉学科研究，有重要的理论意义、广阔的临床价值和产业化前景。

目前尚无能够稳定、缩小动脉粥样硬化（AS）斑块的理想方法。我们前期研究发现：声动力治疗（SDT）能稳定、缩小AS斑块并减轻斑块炎症；诱导斑块巨噬细胞凋亡，促进单核-巨噬细胞的趋化、吞噬及迁移；促进巨噬细胞线粒体细胞色素C（Cyt-C）释放激活线粒体依赖性凋亡途径。但SDT诱导巨噬细胞线粒体Cyt-C释放的机制尚不明确。我们提出设想：SDT作用于AS斑块巨噬细胞，促进巨噬细胞内活性氧产生、细胞内钙增加，进而促进电压依赖性阴离子通道1（VDAC1）发生寡聚化和异寡聚化，在线粒体外膜（OMM）形成足够大的、使Cyt-C释放的孔道。应用已研发的细胞SDT装置，以THP-1巨噬细胞为体外模型。采用siRNA干扰、免疫共沉淀、Western Blot和免疫荧光等技术逐步证实了上述设想。本项目为交叉学科研究，有重要的理论意义、广阔的临床价值和产业化前景。