Division of Cardiovascular Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA.
Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
Am J Hypertens. 2022 May 10;35(5):393-396. doi: 10.1093/ajh/hpab190.
Matrix Gla-protein (MGP) is a well-established inhibitor of vascular calcification that is activated by vitamin K-dependent carboxylation. In the setting of vitamin K2 deficiency, dephospho-uncarboxylated MGP (dpucMGP) levels increase, and have been associated with large artery stiffening. Vitamin K2 is also a mitochondrial electron carrier in muscle, but the relationship of vitamin K2 deficiency and dpucMGP with muscle mass is not well understood. We therefore aimed to examine the association of vitamin K2 deficiency and dpucMGP with skeletal muscle mass in patients with hypertension.
We studied 155 hypertensive adults without heart failure. Axial skeletal muscle mass was measured using magnetic resonance imaging from axial steady-state free precession images. DpucMGP was measured with ELISA. Carotid-femoral pulse wave velocity (CF-PWV) was measured from high-fidelity arterial tonometry recordings.
We found an inverse relationship between dpucMGP levels and axial muscle mass, with progressively rising dpucMGP levels correlating with decreasing axial muscle mass. In an unadjusted linear regression model, correlates of dpucMGP included axial skeletal muscle area factor (β = -0.32; P < 0.0001) and CF-PWV (β = 0.31; P = 0.0008). In adjusted analyses, independent correlates of dpucMGP included axial skeletal muscle area factor (β = -0.30; P = 0.0003) and CF-PWV (β = 0.20; P = 0.019).
In hypertensive adults, dpucMGP is independently associated with lower axial muscle mass, in addition to increased large artery stiffness. Further studies are required to investigate the role of vitamin K supplementation in this population.
基质 Gla 蛋白（MGP）是一种成熟的血管钙化抑制剂，可被维生素 K 依赖性羧化作用激活。在维生素 K2 缺乏的情况下，去磷酸化未羧化 MGP（dpucMGP）水平升高，并与大动脉僵硬有关。维生素 K2 也是肌肉中的线粒体电子载体，但维生素 K2 缺乏与 dpucMGP 与肌肉质量的关系尚未得到很好的理解。因此，我们旨在研究维生素 K2 缺乏与 dpucMGP 与高血压患者骨骼肌质量的关系。
我们研究了 155 名无心力衰竭的高血压成年人。使用来自轴向稳态自由进动图像的磁共振成像测量轴向骨骼肌质量。使用 ELISA 测量 dpucMGP。使用高保真动脉张力记录测量颈动脉-股动脉脉搏波速度（CF-PWV）。
我们发现 dpucMGP 水平与轴向肌肉质量呈负相关，随着 dpucMGP 水平的逐渐升高，与轴向肌肉质量的逐渐降低相关。在未调整的线性回归模型中，dpucMGP 的相关因素包括轴向骨骼肌面积因子（β=-0.32；P<0.0001）和 CF-PWV（β=0.31；P=0.0008）。在调整后的分析中，dpucMGP 的独立相关因素包括轴向骨骼肌面积因子（β=-0.30；P=0.0003）和 CF-PWV（β=0.20；P=0.019）。
在高血压成年人中，dpucMGP 与较低的轴向肌肉质量独立相关，此外还与大动脉僵硬增加有关。需要进一步研究维生素 K 补充在该人群中的作用。
