Ren He, Chen Jiahe, Huang Kai, Qi Ying-Xin
Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, 100083, China.
Institute of Mechanobiology & Medical Engineering, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang, Shanghai, 200240, China.
Mechanobiol Med. 2023 Jul 5;1(1):100003. doi: 10.1016/j.mbm.2023.100003. eCollection 2023 Sep.
We have shown that platelet-derived microvesicles (PMVs) induce abnormal proliferation, migration, and energy metabolism of vascular smooth muscle cells (VSMCs) after vascular intimal injury. Here, we examined a novel role of podosome in mediating matrix metalloproteinase-9 (MMP-9) dependent VSMC migration induced by platelet-derived microvesicles (PMVs). VSMCs were isolated from the thoracic aortas of male Sprague Dawley (SD) rats and identified with immunofluorescent staining. Blood samples were collected from SD Rats, the platelets were isolated with density gradient centrifugation from the blood samples and activated by collagen I. Intriguingly, proteins expressed in platelets were found to participate in the positive regulation of podosome assembly using GO analysis by DAVID, and most of the proteins were found in extracellular exosomes. Of note, activated platelets indirectly induced VSMC migration via releasing PMVs which was verified using platelets and VSMCs transwell co-culture system. Besides, podosome, an invasive protrusion to mediate extracellular matrix (ECM) remodeling, was formed in VSMCs to induce cell migration. Furthermore, MMP-9 activity detected by gelatin zymography was used to verify the function of the podosome in ECM remodeling. The result indicated that MMP-9 activity was robustly activated in VSMCs to implement the function of the podosome. In addition, gelatin degradation was detected in intact VSMCs using a gelatin degradation assay after co-culture with platelets. Taken together, our data reveal a novel mechanism that PMVs promote VSMC migration via forming podosomes and inducing MMP-9 activity.
我们已经表明，血小板衍生的微泡（PMV）在血管内膜损伤后可诱导血管平滑肌细胞（VSMC）异常增殖、迁移和能量代谢。在此，我们研究了足体在介导血小板衍生微泡（PMV）诱导的基质金属蛋白酶-9（MMP-9）依赖性VSMC迁移中的新作用。从雄性Sprague Dawley（SD）大鼠的胸主动脉中分离VSMC，并通过免疫荧光染色进行鉴定。从SD大鼠采集血样，通过密度梯度离心从血样中分离血小板，并用I型胶原激活。有趣的是，使用DAVID的GO分析发现血小板中表达的蛋白质参与足体组装的正调控，并且大多数蛋白质存在于细胞外小体中。值得注意的是，使用血小板和VSMC Transwell共培养系统证实，活化的血小板通过释放PMV间接诱导VSMC迁移。此外，在VSMC中形成了一种用于介导细胞外基质（ECM）重塑的侵袭性突起——足体，以诱导细胞迁移。此外，通过明胶酶谱法检测的MMP-9活性用于验证足体在ECM重塑中的功能。结果表明，MMP-9活性在VSMC中被强烈激活以实现足体的功能。此外，在与血小板共培养后，使用明胶降解试验在完整的VSMC中检测到明胶降解。综上所述，我们的数据揭示了一种新机制，即PMV通过形成足体并诱导MMP-9活性来促进VSMC迁移。
