From the Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston (L.E.D., E.L.N., B.H., S.C.P., A.R.-D., C.B.K.).
Department of Paediatrics, University of Melbourne, Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, Australia (A.F.).
Arterioscler Thromb Vasc Biol. 2019 Oct;39(10):2067-2081. doi: 10.1161/ATVBAHA.119.313077. Epub 2019 Aug 1.
Investigate the requirement of Aggrecan (Acan) cleavage during aortic wall development in a murine model with ADAMTS (a disintegrin-like and metalloprotease domain with thrombospondin-type motifs) 5 deficiency and bicuspid aortic valves.
Mice with altered extracellular matrix remodeling of proteoglycans will be examined for anomalies in ascending aortic wall development. Neo-epitope antibodies that recognize ADAMTS cleaved Acan fragments will be used to investigate the mechanistic requirement of Acan turnover, in aortic wall development.
mice exhibited a high penetrance of aortic anomalies (n=17/17); mice with bicuspid aortic valves (7/17) showed a higher number of anomalies than mice with tricuspid aortic valves. Single mutant mice also displayed a high penetrance of aortic anomalies (n=19/19) compared with wild type (n=1/11). Aortic anomalies correlated with Acan accumulation that was apparent at the onset of elastogenesis in mice. Neo-epitope antibodies that recognize the initial amino acids in the Acan cleaved fragments neo-FREEE, neo-GLGS, and neo-SSELE were increased in the aortas compared with WT. Conversely, neo-TEGE, which recognizes highly digested Acan core fragments, was reduced in mice. However, mice containing a mutation in the TEGE↓ALGSV site, rendering it noncleavable, had low penetrance of aortic anomalies (n=2/4). Acan neo-DIPEN and neo-FFGVG fragments were observed in the aortic adventitia; Acan neo-FFGVG was increased abnormally in the medial layer and overlapped with smooth muscle cell loss in aortas.
Disruption of ADAMTS5 Acan cleavage during development correlates with ascending aortic anomalies. These data indicate that the mechanism of ADAMTS5 Acan cleavage may be critical for normal aortic wall development.
在 ADAMTS5 缺陷和二叶主动脉瓣的小鼠模型中研究聚集蛋白聚糖（Acan）裂解在主动脉壁发育中的需求。
将检查具有改变的蛋白聚糖细胞外基质重塑的小鼠，以研究升主动脉壁发育中的异常。将使用识别 ADAMTS 切割的 Acan 片段的新表位抗体来研究 Acan 周转率在主动脉壁发育中的机械需求。
小鼠表现出主动脉异常的高穿透率（n=17/17）；二叶主动脉瓣的 小鼠（7/17）比三叶主动脉瓣的 小鼠（n=17/17）显示出更多的异常。与野生型（n=1/11）相比，单突变 小鼠（n=19/19）也显示出主动脉异常的高穿透率。与 WT 相比，在 小鼠的弹性发生开始时，Acan 积累明显，与主动脉异常相关。与 Acan 核心片段高度消化的 neo-TEGE 相反，识别 Acan 切割片段初始氨基酸的新表位抗体 neo-FREEE、neo-GLGS 和 neo-SSELE 在 主动脉中增加。然而，在包含 TEGE↓ALGSV 位点突变的小鼠中，使其不可切割，主动脉异常的穿透率低（n=2/4）。在主动脉外膜中观察到 Acan neo-DIPEN 和 neo-FFGVG 片段；Acan neo-FFGVG 在中层中异常增加，并与 主动脉中的平滑肌细胞丢失重叠。
在发育过程中 ADAMTS5 Acan 切割的破坏与升主动脉异常相关。这些数据表明 ADAMTS5 Acan 切割的机制可能对正常主动脉壁发育至关重要。
