Document Detail

Comparison of menaquinone-4 and menaquinone-7 bioavailability in healthy women.
Jump to Full Text
MedLine Citation:
PMID:  23140417     Owner:  NLM     Status:  MEDLINE    
BACKGROUND: Vitamin K₂ contributes to bone and cardiovascular health. Therefore, two vitamin K₂ homologues, menaquinone-4 (MK-4) and menaquinone-7 (MK-7), have been used as nutrients by the food industry and as nutritional supplements to support bone and cardiovascular health. However, little is known about the bioavailability of nutritional MK-4. To investigate MK-4 and MK-7 bioavailability, nutritional doses were administered to healthy Japanese women.
FINDINGS: Single dose administration of MK-4 (420 μg; 945 nmol) or MK-7 (420 μg; 647 nmol) was given in the morning together with standardized breakfast. MK-7 was well absorbed and reached maximal serum level at 6 h after intake and was detected up to 48 h after intake. MK-4 was not detectable in the serum of all subjects at any time point. Consecutive administration of MK-4 (60 μg; 135 nmol) or MK-7 (60 μg; 92 nmol) for 7 days demonstrated that MK-4 supplementation did not increase serum MK-4 levels. However, consecutive administration of MK-7 increased serum MK-7 levels significantly in all subjects.
CONCLUSIONS: We conclude that MK-4 present in food does not contribute to the vitamin K status as measured by serum vitamin K levels. MK-7, however significantly increases serum MK-7 levels and therefore may be of particular importance for extrahepatic tissues.
Toshiro Sato; Leon J Schurgers; Kazuhiro Uenishi
Related Documents :
23826157 - Inflammation's association with metabolic profiles before and after a twelve-week clini...
24388417 - Influence of the immunoassay used in measurement of serum vitamin d levels.
24310287 - Studies on intravitally-determined interrelationships between the activity of asparagin...
24368037 - What is the impact of th1/th2 ratio, socs3, il17, and il35 levels in unexplained infert...
2147887 - Intra- and interindividual variations in contraceptive steroid levels during 12 treatme...
7186047 - Increased [125i]trypsin-binding in serum from cystic fibrosis patients.
Publication Detail:
Type:  Comparative Study; Journal Article; Randomized Controlled Trial     Date:  2012-11-12
Journal Detail:
Title:  Nutrition journal     Volume:  11     ISSN:  1475-2891     ISO Abbreviation:  Nutr J     Publication Date:  2012  
Date Detail:
Created Date:  2012-11-20     Completed Date:  2013-04-12     Revised Date:  2013-07-11    
Medline Journal Info:
Nlm Unique ID:  101152213     Medline TA:  Nutr J     Country:  England    
Other Details:
Languages:  eng     Pagination:  93     Citation Subset:  IM    
Fine Chemical Laboratory, J-OIL MILLS, INC, 1746 Nakashinden, Fukuroi-city, Shizuoka, 437-1111, Japan.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Bone Density Conservation Agents / blood,  metabolism
Cardiovascular Agents / blood,  metabolism
Chromatography, High Pressure Liquid
Dietary Supplements*
Food, Fortified*
Intestinal Absorption*
Limit of Detection
Nutritive Value
Spectrometry, Fluorescence
Vitamin K 2 / analogs & derivatives*,  blood,  metabolism
Young Adult
Reg. No./Substance:
0/Bone Density Conservation Agents; 0/Cardiovascular Agents; 11032-49-8/Vitamin K 2; 27Y876D139/menatetrenone; 8427BML8NY/vitamin MK 7

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Full Text
Journal Information
Journal ID (nlm-ta): Nutr J
Journal ID (iso-abbrev): Nutr J
ISSN: 1475-2891
Publisher: BioMed Central
Article Information
Download PDF
Copyright ©2012 Sato et al.; licensee BioMed Central Ltd.
Received Day: 17 Month: 7 Year: 2012
Accepted Day: 3 Month: 11 Year: 2012
collection publication date: Year: 2012
Electronic publication date: Day: 12 Month: 11 Year: 2012
Volume: 11First Page: 93 Last Page: 93
PubMed Id: 23140417
ID: 3502319
Publisher Id: 1475-2891-11-93
DOI: 10.1186/1475-2891-11-93

Comparison of menaquinone-4 and menaquinone-7 bioavailability in healthy women
Toshiro Sato1 Email:
Leon J Schurgers2 Email:
Kazuhiro Uenishi3 Email:
1Fine Chemical Laboratory, J-OIL MILLS, INC, 1746 Nakashinden, Fukuroi-city, Shizuoka, 437-1111, Japan
2Department of Biochemistry, Cardiovascular Research Institute, University Maastricht, Maastricht, The Netherlands
3Laboratory of Physiological Nutrition, Kagawa Nutrition University, 3-9-2, Chiyoda, Sakado, Saitama, 350-0288, Japan


Vitamin K acts as a cofactor for the endoplasmic enzyme γ- glutamylcarboxylase during the post-translational conversion of glutamic acid residues of specific proteins to γ-carboxyglutamic acid (Gla) to form Gla-containing proteins. A number of blood coagulation factors including coagulation factors II (prothrombin), VII, IX, and X are well-known examples of Gla-containing proteins, which are synthesized in the liver. Osteocalcin, a bone-specific protein synthesized by osteoblasts, and matrix Gla protein synthesized in blood vessel and bone are Gla-containing proteins synthesized at extra-hepatic sites [1].

There are two naturally occurring forms of vitamin K: vitamin K1 (phylloquinone) derived from green plants and vitamin K2 (menaquinones, MK-n), which is a series of vitamers with multi-isoprene units at position 3 of the common 2-methyl-1,4-naphthoquinone ring structure.

In food, vitamin K1 is bound to the chloroplast membrane of leafy green vegetables. MK-4 is found in animal products such as eggs, meat, and liver. MK-4 is derived from the conversion of menadione (synthetic analog of vitamin K only consisting of the 2-methyl-1,4-naphthoquinone ring structure), which is given to the animals. Long chain menaquinones (i.e. MK-7, MK-8, and MK-9) are found in fermented foods such as cheese, curd, and sauerkraut [2]. The Japanese fermented food “natto” contains MK-7 at an exceptionally high concentration [2].

The effects of long chain MK-n such as MK-7 on normal blood coagulation is greater and longer lasting than vitamin K1 and MK-4 [3-5]. The effect of natto derived MK-7 was attributed to its very long half-life in serum, providing a better carboxylation-grade of osteocalcin compared to Vitamin K1[5].

Recent studies revealed that vitamin K2 contributes to both bone and cardiovascular health [6-8]. Both MK-4 and MK-7 have been used as nutritional ingredients. It has been shown that all vitamin K homologues can be converted to MK-4 in vivo[9-11]. MK-4 is thought to have specific functions other than γ-carboxylation of vitamin K-dependent proteins [12,13]. However, only little is known about the bioavailability of the nutritional dose of MK-4 [7]. In this study, we compared the bioavailability of MK-4 and MK-7 and subsequent changes in serum levels in healthy volunteers.


Ten healthy female volunteers (age: 20–21 years, mean BMI: 20.4 kg/m2) not currently taking any medication were selected from the student population of the Laboratory of Physiological Nutrition at Kagawa Nutrition University. Subjects were not allowed to take natto and vitamin supplements other than the experimental versions provided during the study. Approval for both studies was obtained from the Ethics Committee of Kagawa Nutrition University. Informed consent of all volunteers was provided in accordance with the Declaration of Helsinki.

Study 1

Ten healthy female subjects (age: 20–21 years) were randomized into two groups (n = 5). A single dose of MK-4 (420 μg; 945 nmol) or MK-7 (420 μg; 647 nmol) was administered to each subject within 10 min after ingesting a breakfast containing 13–17 g of fat. All subjects received the same meals, and the nutrients and energy levels were adjusted according to the Japanese Dietary Reference Intake and National Health and Nutrition Examination Survey. The amount of 420 μg is equivalent to the MK-7 concentration in natto and is 7 times higher than the recommended dietary intake (RDI) of vitamin K for Japanese women (age: 19–29 years). Blood (2 ml) was taken to prepare serum before the administration of vitamin K at baseline (t=0), and at 2, 4, 6, 8, 10, 24, 48, and 72 h after administration. Serum MK-4 and MK-7 levels were determined by HPLC analysis as described below.

Study 2

Ten healthy female subjects (age: 20–21 years) were randomized into two groups (n = 5). MK-4 (60 μg; 135 nmol) or MK-7 (60 μg; 92 nmol), equivalent to the RDI, was administered daily after supper for one week. Subsequently, serum MK-4 and MK-7 levels were determined.


MK-4 and MK-7 for the analytical standard were gifted by Eisai (Tokyo, Japan) and Hofmann-La Roche (Basel, Switzerland), respectively. Pure MK-4 (98.5%) and MK-7 (98.7%) used for the human study were prepared by J-Oil Mills (Fukuroi, Japan) with purity determined by HPLC [4]. Preparation consisted of dilution into hydrogenated starch hydrolyze powder, which was packed in gelatin capsules. The capsules were then packed in an aluminum-light-shed bag and kept in a refrigerator until use. After study completion, we re-analyzed and confirmed that neither MK-4 nor MK-7 decreased during storage (data not shown).

Measurements of serum vitamin K2

Serum vitamin K was measured using HPLC with fluorescence detection after on-line, post column zinc reduction, which converts quinone forms of vitamin K into their fluorescent quinol forms, as described previously [5]. Samples were extracted using hexane. Vitamin K1-25 (GLSynthesis Inc., Worcester, MA) was used as internal standard. The detection limit of MK-4 and MK-7 were 16 pg/ml and 40 pg/ml, respectively. Results were expressed as the mean ± standard error (SEM).

Study 1

Serum vitamin K2 levels were compared after a single oral administration (420 μg) of MK-4 or MK-7 in healthy Japanese females. Baseline serum levels of MK-4 and MK-7 were not detected. Single intake of MK-7 increased serum MK-7 in all subjects, which reached maximum levels at 6 h after administration. MK-7 was detected 48 h after administration (Figure  1). On the contrary, serum MK-4 was not detected at any time point (Figure  1).

Study 2

Serum vitamin K2 levels were compared after consecutive administration of MK-4 and MK-7 (60 μg/day) for 7 days. Baseline serum level of MK-4 was 2.2 ng/ml ± 0.38 and that of MK-7 was less than detection limit. After subtracting the baseline serum levels from all values, MK-4 levels were 0.00 ng/ml ± 0.77 and 0.03 ng/ml ± 0.27 in the MK-4 and MK-7-treated groups, respectively. While MK-4 intake did not increase MK-4 administered group, serum MK-7 increased significantly in MK-7-administered-subjects (Figure  2).


The current study shows that MK-4 has a poor bioavailability at a nutritional level dose, whereas MK-7 is well absorbed and detectable in the blood at nutritional levels. In a study from the Netherlands, they compared the absorption of 900 μg of vitamin K1, MK-4, and MK-9. MK-4 showed a short serum half-life and small area under the curve compared to vitamin K1, whereas MK-9 displayed a long serum half-life compared to vitamin K1 or MK-4 [14]. Takeuchi et al.[15] reported a dose finding study of MK-4 to increase osteocalcin carboxylation in healthy subjects. In their study, supplementation of 500 μg MK-4/day for 2 months showed no effects on carboxylation of osteocalcin, whereas a dose of 1500 μg MK-4/day was required to improve carboxylation of osteocalcin. From these and our data we can conclude that MK-4 intake of greater than 420–500 μg is required.

Consecutive MK-4 supplementation did not increase plasma MK-4 levels whereas MK-7 supplementation significantly increased plasma MK-7 levels in healthy female subjects. This is in-line with previous published works, which indicated nutritional doses of MK-7 (45–90 μg/day) to be effective for carboxylation of osteocalcin [16,17].

Because all vitamin K homologues can be converted to MK-4 in vivo, MK-4 is considered to have specific functions other than γ-carboxylation of vitamin K-dependent proteins [9-11]. However, in a previous rat study from our group [18], the intake of a nutritional dose of MK-4 did not increase the MK-4 levels in extrahepatic tissues, whereas MK-7 significantly increased MK-4 in extrahepatic tissues. Thus, MK-7 is a better supplier for MK-4 in vivo than MK-4 itself.

In this study, we demonstrated that a nutritional dose of MK-7 is well absorbed in human, and significantly increases serum MK-7 levels, whereas MK-4 had no effect on serum MK-4 levels. Therefore, the nutritional values of vitamin K2 homologues should be differentiated with regard to bioavailability and efficacy.


MK-4: Menaquinone-4; MK-7: Menaquinone-7; RDI: Recommended dietary intake.

Competing interests

TS works for J-OIL MILLS, INC. Other authors have no competing interest.

Authors’ contributions

All authors contributed in the study design. TS and LS were responsible for data collection and analysis. KU was responsible for management of the human clinical study. All authors read and approved of the final manuscript.


We thank Rumi Kawahara for her technical assistance.

Cranenburg EC,Schurgers LJ,Vermeer C,Vitamin K: The coagulation vitamin that became omnipotentThromb HaemostYear: 20079812012517598002
Schurgers LJ,Vermeer C,Determination of phylloquinone and menaquinones in foodHaemostasisYear: 20003029830711356998
Groenen-van Dooren MM,Ronden JE,Soute BA,Vermeer C,Bioavailability of phylloquinone and menaquinones after oral and colorectal administration in vitamin K-deficient ratsBiochem PharmacolYear: 19955079780110.1016/0006-2952(95)00202-B7575640
Sato T,Ohtani Y,Yamada Y,Saitoh S,Harada H,Difference in the metabolism of vitamin K between liver and bone in vitamin K-deficient ratsBr J NutrYear: 20028730731412064340
Schurgers LJ,Teunissen KJ,Hamulyák K,Knapen MH,Vik H,Vermeer C,Vitamin K-containing dietary supplements: comparison of synthetic vitamin K1 and natto-derived menaquinone-7BloodYear: 20071093279328310.1182/blood-2006-08-04070917158229
Fang Y,Hu C,Tao X,Wan Y,Tao F,Effect of vitamin K on bone mineral density: a meta-analysis of randomized controlled trialsJ Bone Miner MetabYear: 201230606810.1007/s00774-011-0287-321674202
Shearer MJ,Newman P,Metabolism and cell biology of vitamin KThromb HaemostYear: 200810053054718841274
Chatrou ML,Reutelingsperger CP,Schurgers LJ,Role of vitamin K-dependent proteins in the arterial vessel wall.HämostaseologieYear: 201231251257
Kimura S,Satoh H,Komai M,The roles of intestinal flora and intestinal function on vitamin K metabolismJ Nutr Sci Vitaminol (Tokyo)Year: 199238suppl4254281297781
Thijssen HH,Vervoort LM,Schurgers LJ,Shearer MJ,Menadione is a metabolite of oral vitamin KBr J NutrYear: 200695260610.1079/BJN2005163016469140
Nakagawa K,Hirota Y,Sawada N,Yuge N,Watanabe M,Uchino Y,Okuda N,Shimomura Y,Suhara Y,Okano T,Identification of UBIAD1 as a novel human menaquinone-4 biosynthetic enzymeNatureYear: 201046811712110.1038/nature0946420953171
Ichikawa T,Horie-Inoue K,Ikeda K,Blumberg B,Inoue S,Steroid and xenobiotic receptor SXR mediates vitamin K2-activated transcription of extracellular matrix-related genes and collagen accumulation in osteoblastic cellsJ Biol ChemYear: 2006281169271693410.1074/jbc.M60089620016606623
Ito A,Shirakawa H,Takumi N,Minegishi Y,Ohashi A,Howlader ZH,Ohsaki Y,Sato T,Goto T,Komai M,Menaquinone-4 enhances testosterone production in rats and testis-derived tumor cellsLipids Health DisYear: 20111015810.1186/1476-511X-10-15821914161
Schurgers LJ,Vermeer C,Differential lipoprotein transport pathways of K-vitamins in healthy subjectsBiochim Biophys ActaYear: 20021570273210.1016/S0304-4165(02)00147-211960685
Takeuchi A,Masuda Y,Kimura M,Marushima R,Matsuoka R,Hasegawa M,Takahama M,Onuki M,Minimal effective dose of vitamin K2 (menaquinone-4) on serum osteocalcin concentration in Japanese subjects and safety evaluation of vitamin K2 supplemented in calcium tabletJ Jpn Soc Clin NutrYear: 200526254260
van Summeren MJ,Braam LA,Lilien MR,Schurgers LJ,Kuis W,Vermeer C,The effect of menaquinone-7 (vitamin K2) supplementation on osteocalcin carboxylation in healthy prepubertal childrenBr J NutrYear: 20091021171117810.1017/S000711450938210019450370
Brugè F,Bacchetti T,Principi F,Littarru GP,Tiano L,Olive oil supplemented with menaquinone-7 significantly affects osteocalcin carboxylationBr J NutrYear: 20111061058106210.1017/S000711451100142521736837
Sato T,Kawahara R,Kamo S,Saito S,Comparison of menaquinone-4 and menaquinone-7 in ratsVitamins (Japan)Year: 200781377381


[Figure ID: F1]
Figure 1 

Change in serum vitamin K2 levels following a single oral dose (420 μg) of MK-4 or MK-7. Each point represents the mean ± SEM of 5 subjects at 0, 2, 4, 6, 10, 24, 48 and 72 h. ■=MK-4; ○=MK-7

[Figure ID: F2]
Figure 2 

Increased serum vitamin K2 levels in subjects after 7 days of consecutive administration (60 μg/day). Each value is expressed as the mean ± SEM of 5 subjects. ■=MK-4;□=MK-7

Article Categories:
  • Short Report

Keywords: Vitamin K2, Menaquinone-4, Menaquinone-7, Bioavailability, Absorption.

Previous Document:  Effects of Structure Dissymmetry on Aggregation Behaviors of Quaternary Ammonium Gemini Surfactants ...
Next Document:  The influence of a complete lower denture destabilization on the pressure of the mucous membrane fou...