In cultured media, menaquinone-7 (0.01-10 μM; 7 days) inhibits osteoclast-like cells [1]. In the presence of the phytoestrogen genistein (1, 10 μM), menaquinone-7 (10 μM) dramatically increases phosphorylated Menaquinone-7 (1, 10 μM) in MC3T3E1 cells and enhances the anabolic effect on femoral calcium levels [3].

In cultured media, menaquinone-7 (0.01-10 μM; 7 days) inhibits osteoclast-like cells [1]. In the presence of the phytoestrogen genistein (1, 10 μM), menaquinone-7 (10 μM) dramatically increases phosphorylated Menaquinone-7 (1, 10 μM) in MC3T3E1 cells and enhances the anabolic effect on femoral calcium levels [3].

Depigmented bone loss is halted by menaquinone-7 (18.1 mg/100 g diet; in animal feed; 24 days) [5].

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The BASIK2 trial is designed to evaluate the effect of Menaquinone-7 on calcification activity in patients with bicuspid aortic valve and calcific aortic valve stenosis using ¹⁸F-NaF PET/MR imaging.[2]

Cell viability assay [1]
Cell Types: Bone marrow cells (from 3-week-old male Wistar rats; stimulated by PTH/PGE2)
Tested Concentrations: 0.01-10 µM
Incubation Duration: 7 days
Experimental Results: The number of TRACP-positive MNCs stimulated by PTH or PGE2 was significant. Dramatically reduces prostaglandin E2.

Animal/Disease Models: Female Wistar rat (5 weeks old; ovariectomized (OVX) rat model)) [5].
Doses: 18.1 mg/100 g Dietary
Route of Administration: animal feed; 24-day
Experimental Results: Preventive effect on bone loss caused by OVX.

Absorption, Distribution and Excretion
Vitamin K exists primarily as vitamin K1 and is mainly absorbed in the jejunum and ileum. …Vitamin K is transported to intestinal cells by micro-macromolecules formed from bile acids and other substances. Intestinal cells secrete vitamin K as chylomicrons into the lymphatic vessels. It enters the bloodstream via the thoracic duct and is transported in the bloodstream as chylomicron residues to various tissues, including the liver, bones, and spleen. In the liver, some vitamin K is stored, some is oxidized to inactive end products, and some is secreted with very low-density lipoprotein (VLDL). Approximately 50% of vitamin K exists in plasma as VLDL, about 25% in low-density lipoprotein (LDL), and about 25% in high-density lipoprotein (HDL). /Vitamin K/
Vitamin K and its metabolites are primarily excreted in feces. A small amount of vitamin K is also excreted in urine. /Vitamin K/
…Menaquinone compounds can only be adequately absorbed by the gastrointestinal tract in the presence of bile acids. However, even in the absence of bile, Menaquinone compounds and their water-soluble derivatives can be absorbed. ... Menaquinone compounds are almost entirely absorbed through the lymphatic system. /Menaquinone/
Menaquinone vitamin K is produced by bacteria in the lower intestine and is abundant in this site. However, their contribution to maintaining vitamin K levels is difficult to assess. Despite great variation in content, the content of vitamin K (Menaquinone mixture) in human liver is about 10 times that of phylloquinone. /Menaquinone/

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Metabolism/Metabolites
One of the main pathways of vitamin K metabolism is the reduction by carboxylase and the recycling of epoxides. /Vitamin K/
Vitamin K undergoes some oxidative metabolism. /Vitamin K/

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Menaquinone-7 has a relatively long half-life of about 3 days. [2]
Compared to vitamin K1, it exhibits significantly higher bioavailability and biological activity in vivo. [2]

Interactions
MK-7 can induce more complete carboxylation of osteocalcin. Hematologists should be aware that daily intake of 50 mcg or more of MK-7 formulations may have clinically significant interference with oral anticoagulation therapy. Broad-spectrum antibiotics can disrupt the gut microbiota, reducing its contribution to vitamin K absorption. /Vitamin K/ Cephalosporins containing an N-methylthiotetrazole side chain (cefotaxime, cefoperazone, cefotetan, cefamandole, latamoxiv) or a methylthiadiazole side chain (cefazoline) can cause vitamin K deficiency and hypoprothrombinemia. These cephalosporins are inhibitors of hepatic vitamin K epoxide reductase. /Vitamin K/ Concomitant use of cholestyramine and vitamin K may reduce vitamin K absorption. /Vitamin K/ For more complete data on interactions of vitamin K2 (16 in total), please visit the HSDB records page.

[1]. Inhibitory effect of menaquinone-7 (vitamin K2) on osteoclast-like cell formation and osteoclastic bone resorption in rat bone tissues in vitro. Mol Cell Biochem. 2001 Dec;228(1-2):39-47.

[2]. Menaquinone-7 regulates gene expression in osteoblastic MC3T3E1 cells. Int J Mol Med. 2007 Feb;19(2):279-84.

[3]. Stimulatory effect of menaquinone-7 on bone formation in elderly female rat femoral tissues in vitro: prevention of bone deterioration with aging. Int J Mol Med. 2002 Dec;10(6):729-33.

[4]. Bicuspid Aortic Valve Stenosis and the Effect of Vitamin K2 on Calcification Using 18F-Sodium Fluoride Positron Emission Tomography/Magnetic Resonance: The BASIK2 Rationale and Trial Design. Nutrients. 2018 Mar 21;10(4):386.

[5]. Yamaguchi M, Taguchi H, Gao YH, Igarashi A, Tsukamoto Y. Effect of vitamin K2 (menaquinone-7) in fermented soybean (natto) on bone loss in ovariectomized rats. J Bone Miner Metab. 1999;17(1):23-9.

Menaquinone-7 is a Menaquinone with seven isoprene units in its side chain and an all-trans configuration. It functions as a metabolite of Mycoplasma genitalium, a bone mineral density maintainer, an Escherichia coli metabolite, a human serum metabolite, and a cofactor. Menaquinone-7 is currently being investigated in the clinical trial NCT00402974 (Effects of Vitamin K Supplementation on Osteocalcin Carboxylation in Healthy Children). Menaquinone-7 has been reported to be detected in Bacillus brevis, with relevant data. Mechanism of Action: In vivo and in vitro studies suggest that vitamin K may act directly on bone metabolism. In vitro studies have shown that vitamin K2 partially inhibits bone resorption by suppressing the production of bone resorption substances such as prostaglandin E2 and interleukin-6. Vitamin K2 has been reported to enhance osteoblast-induced mineralization in vitro and inhibit bone loss in steroid-treated and ovariectomized rats. Certain naphthoquinone compounds, particularly the synthetic vitamin K Menaquinone, have been found to possess in vitro and in vivo antitumor activity. Vitamin K2 has been found to induce in vitro differentiation of myeloid leukemia cell lines. The possible mechanisms of vitamin K's anticancer activity are not fully understood. Menaquinone is an oxidative stress inducer, and its potential anticancer activity may be partly attributed to the induction of apoptosis. One study showed that Menaquinone induces apoptosis through the Fas/Fas ligand system. Another study reported that Menaquinone induces cell cycle arrest and cell death by inhibiting Cda25 phosphatase. Vitamin K acts as a cofactor involved in the post-translational γ-carboxylation of certain protein glutamate residues in vivo. These proteins include vitamin K-dependent coagulation factors II (prothrombin), VII (prothrombin convertase), IX (Christmas factor), X (Stuart factor), protein C, protein S, protein Zv, and a growth arrest-specific factor (Gas6). Unlike other vitamin K-dependent proteins in the blood coagulation cascade, protein C and protein X have anticoagulant effects. Two vitamin K-dependent proteins found in bone are osteocalcin (also known as bone G1a (γ-carboxyglutamate) protein or BGP) and matrix G1a protein or MGP. γ-carboxylation modification is catalyzed by vitamin K-dependent γ-carboxylases. The major gene products of vitamin K-dependent proteins contain a highly homologous domain between the amino terminus of the mature protein and the signal sequence targeting the secretory pathway. This "propeptide" region appears to be both a "docking" or "recognition" site for the enzyme and regulates enzyme activity by lowering the apparent Km value of the substrate at the glutamate site. …A crucial finding for a comprehensive understanding of the detailed mechanism of action of this enzyme is the identification of an intermediate chemical form of vitamin K that is sufficiently basic to abstract the γ-hydrogen from a glutamyl residue. It has been proposed that O₂ first attacks the naphthoquinone carbonyl carbon adjacent to the methyl group, leading to the formation of a dioxane ring, which in turn generates an alkoxide intermediate. /Vitamin K/
For more complete data on the mechanisms of action of vitamin K2 (8 types), please visit the HSDB record page.

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Therapeutic Uses
There is no typical dosage for vitamin K. Some multivitamin preparations contain vitamin K, in the form of vitamin K1 (phylloquinone or Menaquinone) or vitamin K2 (Menaquinone), at doses ranging from 25 to 100 micrograms.
Vitamin K is used to treat warfarin-induced prothrombin deficiency, antibiotic-induced hypoprothrombinemia, and hypoprothrombinemia caused by vitamin C deficiency from various causes, including malabsorption syndrome. Vitamin K
Because vitamin K supplementation is effective in preventing neonatal hemorrhagic diseases, newborns in the United States and Canada are typically given 0.5–1 mg of phylloquinone intramuscularly or 2.0 mg orally within 6 hours of birth. This practice is supported by the American and Canadian Pediatric Societies. Phloroquinone
The current recommendation from the American Academy of Pediatrics is that "all newborns should receive an intramuscular injection of 0.5–1 mg of vitamin K (phylloquinone)." Following this recommendation can effectively prevent vitamin K deficiency bleeding. Vitamin K
For more complete data on the therapeutic uses of vitamin K2 (a total of 8 types), please visit the HSDB records page.
Drug Warnings
…MK-7 can induce more complete carboxylation of osteocalcin. Hematologists should be aware that daily intake of 50 mcg or more of MK-7 preparations may interfere with oral anticoagulation therapy in a clinically significant manner.
Studies have shown that vitamin K may play a role in osteoporosis and vascular health. However, based on current research, this is difficult to determine. Vitamin K
Pregnant and breastfeeding women should avoid supplementing with more than the RDA (65 mcg daily) of vitamin K unless a doctor prescribes a higher dose. Vitamin K
Patients taking warfarin long-term may require dietary counseling to maintain stable vitamin K intake levels. Because habitual vitamin K intake may modulate the warfarin dose in patients using warfarin anticoagulants, these patients should maintain their normal diet and supplementation patterns once an effective dose of warfarin has been determined. /Vitamin K/
For more drug warnings (full) data on vitamin K2 (of 6), please visit the HSDB record page.

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Menaquinone-7 is a form of vitamin K₂ that activates matrix Gla protein (MGP), thereby inhibiting vascular and valve calcification. [2]
The BASIK2 trial was a prospective, double-blind, randomized, placebo-controlled study designed to investigate whether Menaquinone-7 (360 mcg/day) could slow or reverse aortic valve calcification in patients with bicuspid aortic valves and mild to moderate aortic stenosis. [2]
The primary endpoint was the change in ¹⁸F-NaF uptake on PET/MR at 6 months. [2]
Secondary endpoints included changes in CT calcification score, echocardiographic parameters, and left ventricular function. [2]
The choice of a dose of 360 micrograms/day was based on previous dose-exploration studies that demonstrated its effectiveness in reducing nonfunctional MGP. [2]

C46H64O2

649.00

648.49

2124-57-4

Menaquinone-7-13C6;Menaquinone-7-d7;1233937-31-9

5287554

Light yellow to yellow solid powder

0.961

720.1±60.0 °C at 760 mmHg

54ºC

254.9±29.9 °C

0.0±2.3 mmHg at 25°C

1.532

17.05

0

2

20

48

1310

0

CC1=C(C(=O)C2=CC=CC=C2C1=O)C/C=C(\C)/CC/C=C(\C)/CC/C=C(\C)/CC/C=C(\C)/CC/C=C(\C)/CC/C=C(\C)/CCC=C(C)C

RAKQPZMEYJZGPI-LJWNYQGCSA-N

InChI=1S/C46H64O2/c1-34(2)18-12-19-35(3)20-13-21-36(4)22-14-23-37(5)24-15-25-38(6)26-16-27-39(7)28-17-29-40(8)32-33-42-41(9)45(47)43-30-10-11-31-44(43)46(42)48/h10-11,18,20,22,24,26,28,30-32H,12-17,19,21,23,25,27,29,33H2,1-9H3/b35-20+,36-22+,37-24+,38-26+,39-28+,40-32+

2-[(2E,6E,10E,14E,18E,22E)-3,7,11,15,19,23,27-heptamethyloctacosa-2,6,10,14,18,22,26-heptaenyl]-3-methylnaphthalene-1,4-dione

Vitamin K2-7; Vitamin K2(35); Vitamin MK-7

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~5 mg/mL (~7.70 mM)

Solubility in Formulation 1: 0.54 mg/mL (0.83 mM) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), suspension solution; with sonication.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 5.4 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 0.54 mg/mL (0.83 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 5.4 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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 (Please use freshly prepared in vivo formulations for optimal results.)