雷帕霉素可降低严重中膜动脉钙化小鼠模型的动脉矿物质密度并促进有益的血管重塑。
Rapamycin Reduces Arterial Mineral Density and Promotes Beneficial Vascular Remodeling in a Murine Model of Severe Medial Arterial Calcification.
作者信息
Behzadi Parya, Cuevas Rolando A, Crane Alex, Wendling Andrew A, Chu Claire C, Moorhead William J, Wong Ryan, Brown Mark, Tamakloe Joshua, Suresh Swathi, Salehi Payam, Jaffe Iris Z, Kuipers Allison L, Lukashova Lyudmila, Verdelis Konstantinos, St Hilaire Cynthia
机构信息
Department of Medicine, Division of Cardiology, and the Pittsburgh Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
CardioVascular Center, Vascular Surgery, Tufts Medical Center, 800 Washington Street, Boston, MA, 02111-1800, USA.
出版信息
bioRxiv. 2024 Dec 22:2024.08.01.606196. doi: 10.1101/2024.08.01.606196.
Peripheral artery disease (PAD) is the narrowing of the arteries that carry blood to the lower extremities. PAD has been traditionally associated with atherosclerosis. However, recent studies have found that medial arterial calcification (MAC) is the primary cause of chronic limb ischemia below the knee. MAC involves calcification of the elastic fibers surrounding smooth muscle cells (SMCs) in arteries. Matrix GLA protein (MGP) inhibits vascular calcification by binding circulating calcium and preventing hydroxyapatite crystal deposition, while also modulating osteogenic signaling by blocking BMP-2 activation of RUNX2. mice develop severe MAC and die around 8 weeks after birth due to aortic rupture or heart failure. We previously discovered a rare genetic disease Arterial Calcification due to Deficiency in CD73 (ACDC) in which patients present with extensive MAC in their lower extremity arteries. Using a patient-specific induced pluripotent stem cell model we found that rapamycin inhibited calcification. Here we investigated whether rapamycin could reduce MAC in vivo using the murine model. and mice received 5mg/kg rapamycin or vehicle. Calcification content was assessed via microCT, and vascular morphology and extracellular matrix content assessed histologically. Immunostaining and western blot analysis were used to examine SMC phenotype and extracellular matrix content. Rapamycin prolonged mice lifespan, decreased mineral density in the arteries, maintained SMC contractile phenotype, and improved vessel structure, however, calcification volume was unchanged. mice with SMC-specific deletion of Raptor or Rictor, did not recapitulate treatment with rapamycin. These findings suggest rapamycin promotes beneficial vascular remodeling in vessels with MAC.
外周动脉疾病(PAD)是指将血液输送到下肢的动脉变窄。传统上,PAD与动脉粥样硬化有关。然而,最近的研究发现,中膜动脉钙化(MAC)是膝以下慢性肢体缺血的主要原因。MAC涉及动脉中围绕平滑肌细胞(SMC)的弹性纤维钙化。基质GLA蛋白(MGP)通过结合循环钙并防止羟基磷灰石晶体沉积来抑制血管钙化,同时还通过阻断BMP-2对RUNX2的激活来调节成骨信号。 小鼠会发生严重的MAC,并在出生后约8周因主动脉破裂或心力衰竭而死亡。我们之前发现了一种罕见的遗传病——因CD73缺乏导致的动脉钙化(ACDC),该病患者下肢动脉存在广泛的MAC。使用患者特异性诱导多能干细胞模型,我们发现雷帕霉素可抑制钙化。在此,我们使用 小鼠模型研究雷帕霉素是否能在体内减少MAC。 和 小鼠接受5mg/kg雷帕霉素或赋形剂。通过微型计算机断层扫描评估钙化含量,通过组织学评估血管形态和细胞外基质含量。免疫染色和蛋白质免疫印迹分析用于检查SMC表型和细胞外基质含量。雷帕霉素延长了 小鼠的寿命,降低了动脉中的矿物质密度,维持了SMC收缩表型,并改善了血管结构,然而,钙化体积没有变化。具有SMC特异性缺失Raptor或Rictor的 小鼠,并未重现雷帕霉素治疗的效果。这些发现表明雷帕霉素可促进有MAC的血管发生有益的血管重塑。