In a recently published study, researchers assessed the mechanism by which vitamin K affects bone health. Research has previously demonstrated that vitamin K1 (phylloquinone) and vitamin K2 (menaquinone) provide bone-supportive activity.
In this new study, researchers examined the role of vitamin K on the function of osteoblasts, which are the cells responsible for the formation of new bone (anabolism), and function of osteoclasts, which are the cells responsible for bone breakdown or resorption (catabolism). Bone tissue is constantly being broken down and reformed, a process known as remodeling, in order to maintain strength and integrity.
This study showed that vitamin K2 also inhibits activation of nuclear factor kappa-B (NF-kappaB). This nuclear factor is responsible for up-regulating the activity of the osteoclasts, which break down bone, and decreasing the activity of osteoblasts, which increase bone formation. Thus, by inhibiting NF-kappaB, vitamin K2 promotes bone formation.
Additionally, the study showed that vitamin K2 supports bone formation by down-regulating the cytokine tumor necrosis factor alpha (TNF-alpha) as well as inhibiting the binding of the NF-kappaB receptor, which activates osteoclast precursors.
Thus, the study authors concluded, “Our data provide a novel mechanism to explain the dual pro-anabolic and anti-catabolic activities of vitamin K2, and may further support the concept that pharmacological modulation of NF-kappaB signal transduction may constitute an effective mechanism for ameliorating pathological bone loss and for promoting bone health.”
by VRP Staff
Yamaguchi M, Weitzmann MN. Vitamin K2 stimulates osteoblastogenesis and suppresses osteoclastogenesis by suppressing NF-kB activation. Int J Mol Med. 2010 Nov 11. Published Online Ahead of Print.