Lin Tonghui, Wang Xue-Lin, Zettervall Sara L, Cai Yujun, Guzman Raul J
Division of Vascular and Endovascular Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Mass.
Division of Vascular and Endovascular Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Mass.
J Vasc Surg. 2017 Aug;66(2):586-593. doi: 10.1016/j.jvs.2016.03.462. Epub 2016 Jun 30.
Medial artery calcification develops in diabetes, chronic kidney disease, and as part of the aging process. It is associated with increased morbidity and mortality in vascular patients. Bone morphogenetic proteins (BMPs) have previously been implicated in the initiation and progression of vascular calcification. We thus evaluated whether dorsomorphin homologue 1 (DMH1), a highly selective BMP inhibitor, could attenuate vascular calcification in vitro and in an organ culture model of medial calcification.
Confluent human aortic smooth muscle cells (SMCs) were cultured in calcification medium containing 3.0 mM inorganic phosphate (Pi) for 7 days with or without DMH1. Medial calcification was assessed using an aortic organ culture model. Calcification was visualized by alizarin red S staining, and calcium concentration was assessed by an o-cresolphthalein complexone calcium assay. Osteogenic cell and vascular SMC markers were determined by Western blot, quantitative reverse transcription polymerase chain reaction, and immunohistochemical staining.
DMH1 reduced Pi-induced calcium deposition in human SMCs. It also antagonized human recombinant BMP2-induced calcium accumulation. Western blot further revealed that DMH1 was able to block Pi-mediated upregulation of the osteoblast markers osterix and alkaline phosphatase and downregulation of the SMC markers smooth muscle myosin heavy chain and SM22α as well as p-Smad1/5/8, suggesting that DMH1 may regulate SMC osteogenic differentiation through the BMP/Smad1/5/8 signaling pathway. Finally, using an ex vivo aortic ring organ culture model, we observed that DMH1 reduces Pi-induced aortic medial calcification.
The selective BMP inhibitor DMH1 can inhibit calcium accumulation in vascular SMCs and arterial segments exposed to elevated phosphate levels. Such small molecules may have clinical utility in reducing medial artery calcification in our population of vascular patients.
糖尿病、慢性肾病以及衰老过程中均会出现内侧动脉钙化。它与血管疾病患者发病率和死亡率的增加相关。骨形态发生蛋白（BMPs）先前已被认为与血管钙化的起始和进展有关。因此，我们评估了一种高度选择性的BMP抑制剂——多莫吗啡同系物1（DMH1），是否能在体外以及在内侧钙化的器官培养模型中减轻血管钙化。
将汇合的人主动脉平滑肌细胞（SMCs）在含有3.0 mM无机磷酸盐（Pi）的钙化培养基中培养7天，添加或不添加DMH1。使用主动脉器官培养模型评估内侧钙化。通过茜素红S染色观察钙化情况，并用邻甲酚酞络合钙测定法评估钙浓度。通过蛋白质免疫印迹、定量逆转录聚合酶链反应和免疫组织化学染色来测定成骨细胞和血管平滑肌细胞标志物。
DMH1减少了Pi诱导的人平滑肌细胞中的钙沉积。它还拮抗了人重组BMP2诱导的钙积累。蛋白质免疫印迹进一步显示，DMH1能够阻断Pi介导的成骨细胞标志物osterix和碱性磷酸酶的上调，以及平滑肌细胞标志物平滑肌肌球蛋白重链和SM22α以及p-Smad1/5/8的下调，这表明DMH1可能通过BMP/Smad1/5/8信号通路调节平滑肌细胞的成骨分化。最后，使用离体主动脉环器官培养模型，我们观察到DMH1减少了Pi诱导的主动脉内侧钙化。
选择性BMP抑制剂DMH1可以抑制血管平滑肌细胞和暴露于高磷酸盐水平的动脉节段中的钙积累。这类小分子可能在降低我们血管疾病患者群体的内侧动脉钙化方面具有临床应用价值。
