K2 Bone Mechanisms Elucidated

ATLANTAScientists from Emory University School of Medicine have shown vitamin K2 (menaquinone) influences osteoblasts and osteoclasts by acting on nuclear factor kappa-B (NFkB) and tumor necrosis factor-alpha (TNF) activities. Their findings were published Nov. 11 online ahead of print in the International Journal of Molecular Medicine.

Formation of osteoclasts, which remove bone tissue, is dependent on NFkB activation, which also disrupts and inhibits osteoblast formation and activity. The researchers reported K2 down-regulates basal and cytokine-induced NF-B activation, by increasing IB mRNA, in a -carboxylation-independent manner. K2 prevented repression by TNF of SMAD signaling induced by either transforming growth factor ß (TGFß) or bone morphogenetic protein-2 (BMP-2), and further antagonized receptor activator of NF-B (RANK) ligand (RANKL)-induced NF-B activation in osteoclast precursors.

According to the report, the data show a novel mechanism behind K2s pro-anabolic and anti-catabolic actions and suggest modulation of NFkB signal transduction is a viable target for addressing bone loss and bone health.