Low-dose menaquinone-4 improves γ-carboxylation of osteocalcin in young males: a non-placebo-controlled dose–response study

Nakamura, Eriko; Aoki, Mami; Watanabe, Fumio; Kamimura, Ayako

doi:10.1186/1475-2891-13-85

Cited by 16 publications

(16 citation statements)

References 12 publications

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“…This demonstrates the safety of VK2 in this range of daily intake. Furthermore, multiple studies have been performed using VK2 concentrations of up to 45 mg/day [45,85,86]. One isoform of VK2 has received a Generally Recognized as Safe (GRAS) status by the FDA.…”

Section: Safety Datamentioning

confidence: 99%

Vitamin K2 Needs an RDI Separate from Vitamin K1

et al. 2020

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Vitamin K and its essential role in coagulation (vitamin K [Koagulation]) have been well established and accepted the world over. Many countries have a Recommended Daily Intake (RDI) for vitamin K based on early research, and its necessary role in the activation of vitamin K-dependent coagulation proteins is known. In the past few decades, the role of vitamin K-dependent proteins in processes beyond coagulation has been discovered. Various isoforms of vitamin K have been identified, and vitamin K2 specifically has been highlighted for its long half-life and extrahepatic activity, whereas the dietary form vitamin K1 has a shorter half-life. In this review, we highlight the specific activity of vitamin K2 based upon proposed frameworks necessary for a bioactive substance to be recommended for an RDI. Vitamin K2 meets all these criteria and should be considered for a specific dietary recommendation intake.

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Section: Safety Datamentioning

confidence: 99%

Vitamin K2 Needs an RDI Separate from Vitamin K1

et al. 2020

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“…A supplemental intake of 250-1000 µg/day of vitamin K1 activates OC [52], which is higher than the current RDIs of vitamin K in most countries. A markedly higher dose of MK-4 (600-1500 µg/day) is required to activate OC [53,54], as it has been shown to have a very short half-life in humans [37] and it is poorly absorbed [55]. Nutritional doses of MK-4, such as the consecutive intake of 60 µg/day or a single intake of 420 µg, have shown to be ineffective [55].…”

Section: Advantages Of Mk-7mentioning

confidence: 99%

MK-7 and Its Effects on Bone Quality and Strength

Sato¹,

Inaba²,

Yamashita³

2020

Nutrients

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Vitamin K acts as a cofactor and is required for post-translational γ-carboxylation of vitamin K-dependent proteins (VKDP). The current recommended daily intake (RDI) of vitamin K in most countries has been established based on normal coagulation requirements. Vitamin K1 and menaquinone (MK)-4 has been shown to decrease osteocalcin (OC) γ-carboxylation at RDI levels. Among the several vitamin K homologs, only MK-7 (vitamin K2) can promote γ-carboxylation of extrahepatic VKDPs, OC, and the matrix Gla protein at a nutritional dose around RDI. MK-7 has higher efficacy due to its higher bioavailability and longer half-life than other vitamin K homologs. As vitamin K1, MK-4, and MK-7 have distinct bioactivities, their RDIs should be established based on their relative activities. MK-7 increases bone mineral density and promotes bone quality and strength. Collagen production, and thus, bone quality may be affected by MK-7 or MK-4 converted from MK-7. In this review, we comprehensively discuss the various properties of MK-7.

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“…MK-4 has been shown to be bioavailable after oral ingestion in dogs and rats [30,31]. An increased intake of MK-4 has also been shown in several [32][33][34], but not all studies [35], to increase serum MK-4 levels in humans. These studies used supplemental MK-4 and, thus, the bioavailability of MK-4 from the vitamin K-biofortified eggs would need to be established.…”

Section: Discussionmentioning

confidence: 98%

Biofortification of Chicken Eggs with Vitamin K—Nutritional and Quality Improvements

O’Sullivan

Ball

Mcdonald³

et al. 2020

Foods

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National nutrition surveys have shown that over half of all adults in Ireland, the United Kingdom (UK), and the United States of America (USA) have low vitamin K intakes. Thus, dietary strategies to improve vitamin K intakes are needed, and vitamin K biofortification of food may be one food-based approach. The primary aim of our study was to establish whether increasing the vitamin K3 content of hen feed can increase the vitamin K content of eggs, and the secondary aims were to examine the effects on hen performance parameters, as well as egg and eggshell quality parameters. A 12 week hen feeding trial was conducted in which Hyline chickens were randomized into four treatment groups (n = 32/group) and fed diets containing vitamin K3 (as menadione nicotinamide bisulfite) at 3 (control), 12.9, 23.7, and 45.7 mg/kg feed. Vitamin K1, menaquinone (MK)-4, MK-7, and MK-9 were measured in raw whole eggs via a liquid chromatography tandem mass spectrometry method. MK-4 was the most abundant form of vitamin K (91–98%) found in all eggs. Increasing the vitamin K3 content of hen feed over the control level significantly (p < 0.001) enhanced the MK-4 content of eggs (mean range: 46–51 µg/100 g, representing ~42–56% of US Adequate Intake values). Vitamin K biofortification also led to significant (p < 0.05) increases in the yellowness of egg yolk and in eggshell weight and thickness, but no other changes in egg quality or hen performance parameters. In conclusion, high-quality vitamin K-biofortified eggs can be produced with at least double the total vitamin K content compared to that in commercially available eggs.

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Low-dose menaquinone-4 improves γ-carboxylation of osteocalcin in young males: a non-placebo-controlled dose–response study

Cited by 16 publications

References 12 publications

Vitamin K2 Needs an RDI Separate from Vitamin K1

Vitamin K2 Needs an RDI Separate from Vitamin K1

MK-7 and Its Effects on Bone Quality and Strength

Biofortification of Chicken Eggs with Vitamin K—Nutritional and Quality Improvements

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