Physiological role of vitamin K2 (manaquinone-4) that is converted from other vitamin K analogue in animal organs

我们分析了从头合成的甲基萘醌-4 （MK-4）在哺乳动物中的生理作用，以及维生素K抗炎症和调节甾体生成的分子机制。我们通过喂养二氢叶绿醌（dK1）作为维生素K源，建立了肝外组织低维生素K无出血症状的模型，并分析了其表型。dK1饲喂组血浆骨钙素（骨代谢指标之一）水平显著升高。另一方面，血浆钙水平没有变化。因此，饲喂dK1可以促进成骨细胞的分化，而不是骨的翻转。2。为了明确睾丸MK-4在类固醇生成中的直接作用，我们给亚慢性维生素K缺乏大鼠注射脂多糖，没有任何出血，并分析睾丸中睾酮的产生。结果显示，LPS处理降低了睾丸MK-4浓度不同的睾丸激素合成和Cyp11a基因表达。提示睾丸MK-4具有抗炎作用，可维持正常的甾体生成。3。我们利用小鼠巨噬细胞源性细胞分析了维生素K抗炎症的分子机制。MK-4以剂量依赖的方式显著降低LPS刺激的IL-1β、IL-6和TNFα mRNA。用MK-4处理的条件培养基也具有降低炎症细胞因子表达的活性。这些结果表明，MK-4代谢产物或MK-4处理细胞分泌的物质具有抗炎作用。

We analyzed the physiological role of de novo synthesized menaquinone-4 (MK-4) in mammal, and also molecular mechanism of anti-inflammation and regulation of steroidogenesis by vitamin K. I. We developed the model that has low vitamin K in extra-hepatic tissues without any bleeding sym ptom by feeding of dihydrophylloquinone (dK1) as a vitamin K source, and analyzed its phenotype. The plasma osteocalcin level that is one of bone metabolic markers was significantly increased in dK1 feeding group. On the other hand, plasma calcium level was not changed. Therefore dK1 feeding coup d enhance the differentiation of osteoblast not turn over of bone. II. To clarify the direct involvement of testis MK-4 in steroidogenesis, we administered lipopolysaccharide to the subchronic vitamin K deficient rats without any bleeding and analyzed testosterone production in testis. As a result, the synthesis of testosterone and gene expression of Cyp11a was decreased by LPS treatment depending on testis MK-4 concentration. These results indicate that testis MK-4 shows anti-inflammation effect to keep the normal steroidogenesis. III. We analyzed the molecular mechanism of the anti-inflammation by vitamin K using mouse macrophage derived cells. MK-4 significantly reduced IL-1β, IL-6, and TNFα mRNA stimulated by LPS treatment dose-dependent manner. Conditioned medium treated with MK-4 also has a reducing activity of inflammatory cytokine expression. These results suggested that MK-4 metabolite or something secreted from MK-4 treated cells show anti-inflammatory effect.