Progression of Arterial Aging: the Local MCP-1/MMP-2/TGF-beta 1 Signaling Loop

动脉老化的进展：局部 MCP-1/MMP-2/TGF-beta 1 信号环路

• 批准号: 8552341
• 负责人: Mingyi Wang
• 金额: $ 45.86万
• 依托单位: NATIONAL INSTITUTE ON AGING
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8552341
• 关键词: Adenoviruses; Affect; Age; Aging; Animal Model; Aorta; Atherosclerosis; Blood Vessels; CCL2 gene; CCR; Cardiovascular system; Cell Nucleus; Cells; Cellularity; Collagen; Collagen Type I; Complex; Cytosol; Disease; Dose; Elderly; Fibrosis; Gelatinase A; Health; Human; Hypertension; In Vitro; Inflammation; Interruption; MMP2 gene; Matrix Metalloproteinase Inhibitor; Molecular; Organelles; Pathway Analysis; Play; Production; Proteins; Rattus; Risk Factors; Role; Signal Pathway; Signal Transduction; Small Interfering RNA; Smooth Muscle Myocytes; Staining method; Stains; Therapeutic; Time; Transfection; aged; cytokine; extracellular; human TGFB1 protein; nonhuman primate; novel; overexpression; prevent; therapy design

In this study, dual staining shows that with aging MCP-1 and TGF-beta1, a powerful profibrogenic cytokine, markedly increase and co-localize within the aortic wall in the thickened intima of rats, nonhuman primates, and humans. Cardiovascular signaling network analysis indicates that MCP-1 interacts with TGF-beta1 and is centrally located and directly connected with the inflammation cascade, which is closely associated with MMP-2 activation. In vitro study shows that MCP-1 elevates MMP2, a known activator of latent TGF-beta1 in a dose- or time-dependent manner through CCR-2 signaling in cultured vascular smooth muscle cells (VSMC) from young (8 mo) rat aortae, reaching the levels of old cells (30mo). MCP-1 treatment increases activated intracellular and extracellular TGF-beta1 and its downstream molecules collagen types I and III, which is dependent upon MMP-2 activation in young VSMC, reaching levels of untreated old cells. Furthermore, cellular activated TGF-beta1 is distributed and increased in VSMC sub-fractions, including cytosol, the organelles and the nuclei, with aging. Interestingly, knockdown of MCP-1 via siRNA or overexpression of ectopic TIMP-2 by adenovirus transfection reduces activation of MMP-2 and TGF-beta1 and production of invasive capacity of young cells in an MMP-2 activation-dependent manner, resembling that of untreated old cells. These effects are substantially reduced by both CCR-2 and an MMP inhibitor, GM 6001. Of note, TGF-beta1 treatment increases MCP-1, MMP-2, and VSMC invasiveness in a dose-dependent manner in young VSMC, up to levels of old untreated cells. Furthermore, we demonstrate that a novel protein, Vasorin, is markedly down-regulated in the aged arterial wall, which is closely associated with an increase of TGF-beta1 activity and arterial fibrosis. Further in vitro studies indicate that aging also upregulated TGF-beta1, SMAD 2 and collagen I expression within VSMC; Ang II treatment of young VSMC upregulated the levels of TGF-beta1, SMAD 2 and collagen I expression up to the same levels as from old cells; aging down-regulated Vasorin expression in old rat VSMC as compared with young; TGF-beta1 interacts with Vasorin in rat VSMC; aging affects the interaction of TGF-beta1 with Vasorin; overexpression of Vasorin counteracts TGF-beta1 signaling pathway and collagen I expression in VSMC from old rats; overexpression of Vasorin counteracts TGF-beta1 signaling pathway and collagen I expression induced by Ang II treatment in VSMC from young rats. Taken together, this complex local signaling loop of MCP-1/MMP-2/TGF-beta1 plays a bedrock role in the initiation and progression of age-associated arterial intimal cellularity and fibrosis. Interruption of this vicious cycle is a potential therapeutic approach to arterial health in the elderly.

在这项研究中，双重染色显示，随着年龄的增长，MCP-1和TGF-β 1，一种强大的促纤维化细胞因子，显着增加，并共同定位在大鼠，非人灵长类动物和人类的主动脉壁内膜增厚。心血管信号网络分析表明，MCP-1与TGF-β 1相互作用，位于中心并直接与炎症级联反应相关，而炎症级联反应与MMP-2活化密切相关。体外研究表明，MCP-1通过CCR-2信号以剂量或时间依赖性方式升高来自年轻（8个月）大鼠直肠的培养血管平滑肌细胞（VSMC）中的MMP 2（一种已知的潜在TGF-β 1激活剂），达到老年细胞（30个月）的水平。MCP-1处理增加了活化的细胞内和细胞外TGF-β 1及其下游分子胶原蛋白I型和III型，这取决于年轻VSMC中MMP-2的活化，达到未处理的老细胞的水平。此外，细胞活化的TGF-β 1在VSMC亚组分中分布并增加，包括细胞质、细胞器和细胞核，随着年龄的增长。有趣的是，通过siRNA敲低MCP-1或通过腺病毒转染过表达异位TIMP-2，以MMP-2激活依赖性方式减少MMP-2和TGF-β 1的激活以及年轻细胞侵袭能力的产生，类似于未处理的老年细胞。CCR-2和MMP抑制剂GM 6001可显著降低这些作用。值得注意的是，TGF-β 1治疗以剂量依赖性方式增加年轻VSMC中MCP-1、MMP-2和VSMC的侵袭力，直至达到未治疗的老细胞的水平。 此外，我们证明了一种新的蛋白质，Vasorin，是显着下调，在老年动脉壁，这是密切相关的TGF-β 1活性和动脉纤维化的增加。进一步的体外研究表明，衰老也上调了VSMC内TGF-β 1、SMAD 2和胶原I的表达，Ang II处理年轻VSMC上调了TGF-β 1、SMAD 2和胶原I的表达水平，达到与老年细胞相同的水平，与年轻相比，衰老下调了老年大鼠VSMC中Vasorin的表达，大鼠VSMC中TGF-β 1与Vasorin相互作用，衰老影响TGF-β 1与Vasorin的相互作用; Vasorin的过表达抵消了老年大鼠VSMC中TGF-β 1信号通路和胶原I的表达; Vasorin的过表达抵消了年轻大鼠VSMC中由Ang II处理诱导的TGF-β 1信号通路和胶原I的表达。 总之，MCP-1/MMP-2/TGF-β 1的这种复杂的局部信号传导回路在年龄相关的动脉内膜细胞结构和纤维化的起始和进展中起着基石作用。中断这种恶性循环是老年人动脉健康的潜在治疗方法。