Department of Endocrinology and Diabetes, University Campus Bio-Medico of Rome, 00128 Rome, Italy.
Department of Endocrinology and Diabetes, University Campus Bio-Medico of Rome, 00128 Rome, Italy.
Metabolism. 2017 May;70:57-71. doi: 10.1016/j.metabol.2017.01.032. Epub 2017 Feb 4.
Vitamin K is a liposoluble vitamin. The predominant dietary form, phylloquinone or vitamin K1, is found in plants and green vegetables; whereas menaquinone, or vitamin K2, is endogenously synthesized by intestinal bacteria and includes several subtypes that differ in side chain length. Aside from its established role in blood clotting, several studies now support a critical function of vitamin K in improving bone health. Vitamin K is in fact required for osteocalcin carboxylation that in turn regulates bone mineral accretion; it seems to promote the transition of osteoblasts to osteocytes and also limits the process of osteoclastogenesis. Several observational and interventional studies have examined the relationship between vitamin K and bone metabolism, but findings are conflicting and unclear. This systematic review aims to investigate the impact of vitamin K (plasma levels, dietary intake, and oral supplementation) on bone health with a particular interest in bone remodeling, mineral density and fragility fractures.
维生素 K 是一种脂溶性维生素。主要的膳食形式，叶绿醌或维生素 K1，存在于植物和绿色蔬菜中；而甲萘醌，或维生素 K2，是由肠道细菌内源性合成的，包括几种在侧链长度上有所不同的亚型。除了其在血液凝固中的既定作用外，几项研究现在支持维生素 K 在改善骨骼健康方面的关键作用。维生素 K 实际上是骨钙素羧化所必需的，而骨钙素羧化又反过来调节骨矿物质的积累；它似乎促进成骨细胞向骨细胞的转化，并限制破骨细胞的形成过程。几项观察性和干预性研究已经检查了维生素 K（血浆水平、饮食摄入和口服补充）与骨代谢之间的关系，但研究结果相互矛盾且不明确。本系统评价旨在研究维生素 K（血浆水平、饮食摄入和口服补充）对骨骼健康的影响，特别关注骨重塑、矿物质密度和脆性骨折。
