我们前期成果证实细胞泡沫化时容积调节性氯通道(VRCC)的活性增强，抑制其活性可减轻细胞泡沫化。预试验发现VRCC的作用为CD36依赖且CD36与GPI-AP结合增多。我们据此假设：“VRCC是动脉粥样硬化(AS)防治的新靶点：VRCC活化将导致胞内环境酸化，进而上调酸敏感蛋白Arf，促进脂筏中CD36与GPI-AP结合、局部质膜内凹、进而加速CD36介导的对胞外ox-LDL的吞噬，促进AS”。本项目拟在高脂饮食引起的AS家兔模型上结合VRCC阻断剂观察VRCC对AS的作用及相关信号调控因子的在体变化；同时分离上述各组家兔腹腔巨噬细胞，利用蛋白印迹、荧光标记等技术，观察CD36介导的脂质摄取途径在VRCC促AS中作用；此外，结合siRNA沉默技术，进一步探讨Arf介导的信号通路对CD36介导的胆固醇内吞的调节机制。项目的完成将为AS的病理机制提供新的认识，并为AS的防治提供新的可供干预的靶点。

We had previously reported that the activity of volume-regulated chloride channel (VRCC) increased in the process of macrophage-derived foam cell formation. We also found that inhibition of VRCC activity attenuated ox-LDL-induced introcellular lipid accumulation in macrophages. However, the effects of VRCC on atherosclerosis (AS) and its mechanisms are still unclear. Our preliminary results demonstrated that the effects of VRCC was CD36-dependent. Activation of VRCC by hypotonic medium upregulated the functional activity of CD36 and increased CD36-related GEEC formation. Therefore, we hypothesized that VRCC is a new target for AS treatment. Activation of VRCC should enhance the function of pH-sensitive Arf, which would subsequently promote the binding of CD36 with GPI-AP to form GEEC and augment CD36-mediated lipid uptake. These effects would facilitate VRCC-induced AS formation finally. In this project, we give rabbits with high-fat diet to induce atherosclerosis and study the effects of VRCC on AS with VRCC blockers. Besides, we will also investigate the effects of VRCC on CD36 and CD36-associated GEECs on macrophages, which were cultured from AS rabbits treated with or without VRCC blockers. Furthermore, we will silence Arf gene using siRNA to explore the role of the Arf-mediated signaling pathway in VRCC-induced AS. With these approaches, we aim to perfect the theory of AS and lead to a new perspective for the prevention and treatment of atherosclerosis.

动脉粥样硬化（AS）引起的心脑血管疾病意外已经超过恶性肿瘤成为危害人类生命安全最主要的“凶手”，但是AS发生发展的具体机制至今尚未完全了解。本项目通过给apoE-/-小鼠高脂饮食建立经典的小鼠AS模型，并在此基础上第一次证实NPPB和9-AC在下调VRCC通道蛋白分子LRRC8A的表达的同时可以显著改善小鼠AS程度；此外，利用小鼠源性巨噬细胞株RAW264.7，我们还在细胞水平进一步证实巨噬细胞泡沫化过程中容积调节性氯通道（VRCC）蛋白分子LRRC8A的表达上调，而激活或抑制VRCC可以相应促进或抑制巨噬细胞泡沫化。同时，我们进一步证实了CD36 受体介导的胆固醇摄取是VRCC诱导巨噬细胞泡沫化的主要机制，而胞浆内小G蛋白Arf6的活化与VRCC诱导的细胞泡沫化密切相关。上述结果不仅首次证实VRCC是AS防治的新靶点，同时也初步阐明了VRCC诱导AS的可能机制。本项目的完成将有助于进一步完善AS病理生理机制并为AS药物干预提供新的可作用环节，为临床抗AS药物的研发提供新靶点。