Rb/TSC2基因介导的协同效应抑制血管平滑肌细胞增殖的机制研究

Uncontroled proliferation of Vascular Smooth Muscle Cells (VSMCs) is the major cause of restenosis for vascular diseases. Our team found that knockdown of both Rb and TSC2 leads to synergistic inhibition proliferation in VSMCs. Our team also identified that the synergistic inhibition effect is caused by oxidative stress. Previous research has shown that in addition to the oxidative stress, synergistic effect can also cause endoplasmic reticulum stress and metabolism stress. Theoretically predicts oxidative stress is the key control point for inhibition of VSMCs proliferation of synergistic effect, however, the relationship between endoplasmic reticulum stress and oxidative stress are not clear, also not clear between metabolism stress and oxidative stress. This project intends to 1) Regulate the expression of key genes in endoplasmic reticulum stress and main product synthesis. 2) Regulate the key kinase activity and main product synthesis. Explore the mechanism of endoplasmic reticulum stress and metabolic stress caused by synergistic effect. Discover the mechanism between endoplasmic reticulum stress, metabolism stress and oxidative stress, and providing new ideas and solutions for prevention vascular restenosis diseases.

血管平滑肌细胞（VSMCs）的无序增殖是血管狭窄性疾病发生的必要前提。申请者发现同时敲除Rb和TSC2基因介导的协同效应能够抑制VSMCs增殖。申请者同时发现，这是由于协同效应引起了细胞发生氧化应激而引起的。既往有研究表明，除氧化应激外，协同效应还能够引起细胞发生内质网应激和代谢性应激。理论预测氧化应激为协同效应抑制VSMCs增殖的关键调控点，但目前内质网应激和代谢性应激与氧化应激之间的相关性及具体作用机制并不清楚。本项目拟通过1）调控内质网应激中关键基因的表达及主要产物的合成；2）调控代谢性应激中的关键激酶活性及主要产物的合成。探索协同效应引起内质网应激和代谢性应激的机制；明确内质网应激与氧化应激，代谢性应激与氧化应激之间的精细调控机制，为血管再狭窄疾病的防治拓展新的思路和方案。

血管平滑肌细胞（VSMCs）的无序增殖是血管狭窄性疾病发生的主要原因。前期研究中发现：敲除Rb和TSC2基因介导的协同效应能够抑制VSMCs增殖。这是由于协同效应引起了细胞发生氧化应激而引起的。既往有研究表明，除氧化应激外，协同效应还能够引起细胞发生内质网应激和代谢性应激。申请者在研究过程中发现：1.RB/E2F信号通路调控PDGF诱导的VSMC增殖；2.TSC2/mTOR信号通路调控PDGF诱导的VSMC增殖;3.激活RB/E2F及TSC2/mTOR信号通路介导的协同效应抑制PDGF诱导的VSMC增殖；4.激活RB/E2F及TSC2/mTOR信号通路介导的氧化应激抑制VSMC的增殖；5.激活RB/E2F及TSC2/mTOR信号通路介导的内质网应激抑制VSMC的增殖；6. 激活RB/E2F及TSC2/mTOR信号通路抑制VSMC的迁移。.在研究过程中，研究者同时注意到： VSMCs的表型转化是血管狭窄性疾病发生的必要前提，而组蛋白变体H2A.Z能够与VSMCs的标志基因启动区域选择性的结合，维持VSMCs的收缩型表型。申请者在研究过程中进一步发现：1.单细胞RNA测序揭示H2A.Z和VSMC特性之间较强的相关性；2.H2A.Z直接调节VSMC特异性基因的表达；3.H2A.Z占有率的动态变化与VSMC表型转换密切相关；4.H2A.Z降低VSMC标记基因的核小体占有率；5.H2A.Z促进SMAD3向VSMC标记基因的募集；6.H2A.Z促进MED1占据VSMC标记基因；7.过表达H2A.Z可减轻由损伤诱导的VSMC去分化和内膜形成。.上述发现能够有力的推动血管再狭窄的防治，成为防治血管再狭窄新的突破点，为治疗血管再狭窄提供新的思路和方法。