Phosphocalcic metabolism and the role of vitamin D, vitamin K2, and nattokinase supplementation

Calcium is involved in bone metabolism, regulation of nerve signaling, and release of neurotransmitters. Phosphorus is a structural component of ATP, participates in metabolic energy regulation, and ensures stability to biological membranes and cells. Vitamin D and vitamin K are important for intestinal absorption and renal excretion of calcium and phosphorus. Vitamin D plays a regulatory role in bone formation, carbohydrate metabolism, immune responses, and cardiovascular regulation. Research has linked vitamin D deficiency to the development of diabetes mellitus, hypertension, cancer, and osteoporosis. Vitamin K has been associated with a reduced risk of osteoporosis, cancer, and cardiovascular diseases (due to improved vascular elasticity). This review highlights the importance of vitamins D and K in the metabolism of calcium and phosphorus and explores various molecular mechanisms that help maintain the system's mineral homeostasis. Moreover, the paper reviews the enzyme nattokinase's role in thrombotic prevention due to its fibrinolytic activity.

Effect of vitamin K2 and vitamin D3 on bone mineral density in children with acute lymphoblastic leukemia: a prospective cohort study

OBJECTIVES

Current treatment protocols in acute lymphoblastic leukemia (ALL) are associated with high remission rates and long life expectancy, enhancing the importance of quality of life and prevention of treatment-related complications in patient care. As osteoporosis is a frequent complication in patients under chemotherapy, we investigated the effect of vitamin K2 (100 mcg menaquinone-7) and vitamin D3 (10 mcg calcitriol) on bone metabolism in children with ALL.

METHODS

Twenty-nine consecutive patients recently diagnosed with B precursor ALL (B-ALL) and treated according to the Turkish Acute Lymphoblastic Leukemia Berlin Frankfurt Münster 2000 protocol were randomly assigned into study and control groups. The study group (n=15, M/F: 8/7, age 1-14.5 years, mean 6.5 years) received vitamin K2 and vitamin D3 with their chemotherapy, while the control group (n=14, M/F 9/5, age 2-17 years, mean 7.1 years) received chemotherapy only. Serum calcium, phosphorus, magnesium, alkaline phosphatase, bone-specific alkaline phosphatase, uncarboxylated osteocalcin (ucOC), tartrate resistant acid phosphatase 5b, carboxyl terminal procollagen propeptide (PICP), osteoprotegerin (OPG), and receptor activator nuclear kappa B ligand (RANKL) were measured and bone mineral density (BMD) was determined at baseline and first, second, third and sixth months.

RESULTS

The study group had higher serum OPG/RANKL ratio and lower ucOC levels compared to the control group at the first month; PICP levels were higher in the study group at second and third months.

CONCLUSIONS

These results suggest an early beneficial effect of the combination of vitamin K2 and vitamin D3 on BMD in ALL patients especially during the period of intensive steroid therapy in the first months.

The Dual Role of Vitamin K2 in "Bone-Vascular Crosstalk": Opposite Effects on Bone Loss and Vascular Calcification

Osteoporosis (OP) and vascular calcification (VC) represent relevant health problems that frequently coexist in the elderly population. Traditionally, they have been considered independent processes, and mainly age-related. However, an increasing number of studies have reported their possible direct correlation, commonly defined as “bone-vascular crosstalk”. Vitamin K2 (VitK2), a family of several natural isoforms also known as menaquinones (MK), has recently received particular attention for its role in maintaining calcium homeostasis. In particular, VitK2 deficiency seems to be responsible of the so-called “calcium paradox” phenomenon, characterized by low calcium deposition in the bone and its accumulation in the vessel wall. Since these events may have important clinical consequences, and the role of VitK2 in bone-vascular crosstalk has only partially been explained, this review focuses on its effects on the bone and vascular system by providing a more recent literature update. Overall, the findings reported here propose the VitK2 family as natural bioactive molecules that could be able to play an important role in the prevention of bone loss and vascular calcification, thus encouraging further in-depth studies to achieve its use as a dietary food supplement.

Effects of vitamin K2 combined with methotrexate against mitogen-activated peripheral blood mononuclear cells of healthy subjects and rheumatoid arthritis patients

BACKGROUND

Methotrexate (MTX) is used as anchor drug for patients with early and established rheumatoid arthritis (RA). Vitamin K₂ administration was also reported to be associated with decreased disease activity in RA.

OBJECTIVES

Immunosuppressive pharmacodynamics of vitamin K₂ combined with MTX was investigated.

METHODS

Mitogen-activated peripheral blood mononuclear cells (PBMCs) were used to evaluate immunosuppressive pharmacodynamics of drugs in vitro.

RESULTS

Vitamin K₂ alone dose-dependently suppressed T cell mitogen-activated proliferation of PBMCs of both healthy subjects and RA patients. 446.5 and 2232.5 ng/mL vitamin K₂ significantly decreased the IC₅₀ values of MTX on the proliferation of PBMCs of RA patients, with little influences on the pharmacodynamics of MTX in the healthy PBMCs. 4465 ng/mL vitamin K₂ potentiated the pharmacodynamics of MTX in both RA patients and healthy PBMCs. The additional effects of vitamin K₂ to potentiate the suppressive effects of MTX seemed not to be related to the regulation of CD4⁺ CD25⁺ T cells or CD4⁺ CD25⁺ Foxp3⁺ Treg cells. MTX alone at 100 ng/mL significantly decreased the percentage of CD4⁺ T cells in PBMCs of healthy subjects (p < 0.001) with a slight influence in that of RA patients (not significant) and the combination did not show synergistic inhibitory effect. Vitamin K₂ alone tended to suppress the secretion of IL-17, IFN-γ, and TNF-α from the activated PBMCs of RA patients with smaller influences on the cytokine productions from healthy PBMCs. These additional effects of vitamin K₂ were also observed in combination with MTX.

CONCLUSION

The above information may partially elucidate the potentiation effects of vitamin K₂ on the immunosuppressive efficacy of MTX.

Molecular Mechanism of Vitamin K2 Protection against Amyloid-β-Induced Cytotoxicity

The pathological role of vitamin K2 in Alzheimer's disease (AD) involves a definite link between impaired cognitive functions and decreased serum vitamin K levels. Vitamin K2 supplementation may have a protective effect on AD. However, the mechanism underlying vitamin K2 protection has not been elucidated. With the amyloid-β (Aβ) cascade hypothesis, we constructed a clone containing the C-terminal fragment of amyloid precursor protein (β-CTF/APP), transfected in astroglioma C6 cells and used this cell model (β-CTF/C6) to study the protective effect of vitamin K2 against Aβ cytotoxicity. Both cellular and biochemical assays, including cell viability and reactive oxygen species (ROS), assays assay, and Western blot and caspase activity analyses, were used to characterize and unveil the protective role and mechanism of vitamin K2 protecting against Aβ-induced cytotoxicity. Vitamin K2 treatment dose-dependently decreased the death of neural cells. The protective effect of vitamin K2 could be abolished by adding warfarin, a vitamin K2 antagonist. The addition of vitamin K2 reduced the ROS formation and inhibited the caspase-3 mediated apoptosis induced by Aβ peptides, indicating that the mechanism underlying the vitamin K2 protection is likely against Aβ-mediated apoptosis. Inhibitor assay and Western blot analyses revealed that the possible mechanism of vitamin K2 protection against Aβ-mediated apoptosis might be via regulating phosphatidylinositol 3-kinase (PI3K) associated-signaling pathway and inhibiting caspase-3-mediated apoptosis. Our study demonstrates that vitamin K2 can protect neural cells against Aβ toxicity.

The effects of eggshell calcium (Biomin H® ) and its combinations with alfacalcidol (1α-hydroxyvitamin D3) and menaquinone-7 (vitamin K2) on ovariectomy-induced bone loss in a rat model of osteoporosis

The purpose of this study was to investigate the impact of eggshell calcium (Biomin H® dietary supplement) and its combinations with alfacalcidol (1α-hydroxyvitamin D3 ) and menaquinone-7 (vitamin K2 ) on ovariectomy-induced bone loss in rats. Adult female rats (n = 48) were divided into 6 groups of 8 individuals each: sham-operated rats (SHAM); ovariectomized (OVX) rats untreated; OVX rats treated with Biomin H® (BIO); OVX rats simultaneously receiving Biomin H® , vitamin D3 (BIO + D3 ); OVX rats simultaneously treated with Biomin H® , vitamin K2 (BIO + K2 ) and OVX rats treated with Biomin H® , vitamin D3 , vitamin K2 (BIO + D3  + K2 ) during 8 weeks. Biochemical parameters, bone mineral density (BMD), bone mineral content (BMC) and femoral bone microstructure were determined. Plasma calcium and phosphate were increased in BIO + D3 and BIO + D3  + K2 groups as compared to OVX. Alkaline phosphatase was elevated in OVX, BIO versus SHAM, BIO + D3  + K2 groups. When compared to OVX group, decreased urine deoxypyridinoline was observed in all treated groups and femoral BMD, BMC were higher in BIO, BIO + D3 , BIO + D3  + K2 groups. The BIO + K2 rats had similar densitometrical values than OVX individuals. Microcomputed tomography revealed increased trabecular relative bone volume (due to an increase in trabecular number) in BIO + D3 , BIO + D3  + K2 as compared to OVX. The higher relative bone volume in BIO + D3 , BIO + D3  + K2 groups was also accompanied by an increase in bone surface. In the cortical bone, an enhanced periosteal bone apposition was identified in BIO, BIO + D3 , BIO + K2 , BIO + D3  + K2 groups. The rats from BIO + D3  + K2 group had a higher area of primary osteon's vascular canals. In BIO + D3 , BIO + K2 , BIO + D3  + K2 groups, an increased area of secondary osteons was determined in comparison with OVX. Our results indicate the beneficial effect of triple application of Biomin H® , vitamin D3 , vitamin K2 , as well as simultaneous administration of Biomin H® , vitamin D3 on the inhibition of ovariectomy-induced bone loss in a rat model of osteoporosis.

Network and 16S rRNA Sequencing-Combined Approach Provides Insightal Evidence of Vitamin K2 for Salt-Sensitive Hypertension

Vitamin K₂ (VK2), found to act to treat hypertension, has been widely used in the food and pharmaceutical industries nowadays. However, the potential targets and molecular mechanisms of VK2 for salt-sensitive hypertension have not been fully investigated. Therefore, the study aimed to investigate the potential molecular mechanisms of VK2 for salt-sensitive hypertension using network pharmacology and 16S rRNA sequencing strategy. The network pharmacology-based findings from KEGG enrichment analysis revealed that VK2-treated salt-sensitive hypertension was mechanically associated with the complement and coagulation cascades, calcium signaling pathway, renin–angiotensin system, etc. A total of 29 different bacteria in an animal experiment after VK2 supplementation were screened and functionally enriched using PICRUSt2. Additionally, 10 signaling pathways were identified in which the renin–angiotensin system was found to be the potential molecular mechanisms with the greatest change in multiple and statistical significance. Moreover, the results of the renin–angiotensin system-related protein expression exhibited VK2-inhibited renin–angiotensin system in salt-induced hypertensive mice, which significantly verified the previous biological and functional prediction analysis. Finally, spearman correlation analysis showed the different bacteria such as Dubosiella, Ileibacterium, etc., had a positive or negative correlation with renin–angiotensin system-related proteins in salt-induced mice. In conclusion, the potential molecular mechanisms of VK2 for salt-sensitive hypertension may be beneficially achieved by the specific inhibition of the renin–angiotensin system, contributing to the development for a new preventive strategy of salt-sensitive hypertension.

The Medical Benefits of Vitamin K2 on Calcium-Related Disorders

BACKGROUND

Due to the potentially crucial role of vitamin K2 in calcium metabolism, a deficit can disrupt many mechanisms, resulting in an array of different issues, such as broken bones, stiff arteries and poor fertility. Although there has been existing research, the potential of vitamin K2 as a treatment for conditions including cerebral palsy, parathyroid disease, heart disease and gastrointestinal disease is unknown. This review discusses the biochemistry of vitamin K and the metabolism of calcium, followed by an analysis of the current literature available on vitamin K2 and its prospects.

METHODS

Using public libraries including PubMed and Wiley, we searched for existing research on the metabolism and use of vitamin K2 that has been conducted in the preceding two decades.

RESULTS

Data indicated that vitamin K2 had a positive impact on osteoporosis, cardiovascular disease, parathyroid disorders, cerebral palsy and sperm motility.

CONCLUSION

Due to the existence of confounding variables and limitations in the quality and volume of research conducted, further investigation must be done to see whether the beneficial effects seen are reproducible and must assess the viability of vitamin K2 as treatment in isolation for these conditions.

The Use of Vitamin K2 in Patients With Parkinson's Disease and Mitochondrial Dysfunction (PD-K2): A Theranostic Pilot Study in a Placebo-Controlled Parallel Group Design

Background: Despite rapid advances in research on Parkinson's disease (PD), in particular in the elucidation of genetic contributions, no disease-modifying therapy has become available to date.

Objectives: In the proposed project, we aim to investigate the potential effects of vitamin K2 (long-chain menaquinone 7, MK-7) in genetically determined PD with mitochondrial dysfunction.

Methods: A total of 130 study participants (26 biallelic Parkin/PINK1 mutation carriers, 52 sporadic PD patients, and 52 healthy controls) will receive the trial medication (MK-7 or placebo for 1 week). 31P-Magnetic resonance spectroscopy imaging of the forebrain and basal ganglia (31P-MRSI, primary endpoint) as well as other advanced neuroimaging methods, clinical assessment, including quantitative movement analysis, and biomarker sampling will be applied pre- and post-intervention.

Innovation: The proposed project is highly translational as it builds on compelling mechanistic data from animal studies as well as on a small preliminary data set in humans. Patients are selected based on their mutation-related mitochondrial dysfunction and compared to disease and a healthy control group in a personalized medicine approach. We will further investigate how neuroimaging and blood-derived biomarkers can predict individual treatment response in sporadic PD.

Clinical trial registration: This study was registered at the German Clinical Trial Registry (DRKS, DRKS00019932) on the 19th of December 2019.

Vitamin K2 Alleviates Insulin Resistance in Skeletal Muscle by Improving Mitochondrial Function Via SIRT1 Signaling

Aims: High-fat diet (HFD)-induced insulin resistance (IR) impairs skeletal muscle mitochondrial biogenesis and functions, adversely affecting human health and lifespan. Vitamin K2 (VK2) has a beneficial role in improving insulin sensitivity and glucose metabolism. However, the underlying molecular mechanisms of VK2 on insulin sensitivity have not been well established. We investigated VK2's modulation of mitochondrial function to protect against IR in mice and cell models. Results: VK2 supplementation could effectively ameliorate the development of IR by improving mitochondrial function in both HFD-fed mice and palmitate acid-exposed cells. We revealed for the first time that HFD-caused mitochondrial dysfunction could be reversed by VK2 treatment. VK2 enhanced the mitochondrial function by improving mitochondrial respiratory capacity, increasing mitochondrial biogenesis and the enzymatic activities of mitochondrial complexes through SIRT1 signaling. The benefits of VK2 were abrogated in C₂C₁₂ transfected with SIRT1 siRNA but not in C₂C₁₂ transfected with AMPK siRNA. VK2 and SRT1720, a specific agonist of SIRT1, had the same effect on improving mitochondrial function via SIRT1 signaling. Thus, SIRT1 is required for VK2 improvement in skeletal muscle. Further, the beneficial effects of both VK2 and geranylgeraniol contribute to inhibited IR in skeletal muscle via SIRT1. Innovation and Conclusion: These studies demonstrated a previously undiscovered mechanism by which VK2 alleviates IR in skeletal muscle by improving mitochondrial function via SIRT1. Naturally occurring VK2 prevents IR by improving mitochondrial function through SIRT1 signaling. These results could provide a foundation to identify new VK2-based preventive and therapeutic strategies for IR.

Vitamin K2 Suppresses Proliferation and Inflammatory Cytokine Production in Mitogen-Activated Lymphocytes of Atopic Dermatitis Patients through the Inhibition of Mitogen-Activated Protein Kinases

Vitamin K2 is suggested to have a suppressive effect on the peripheral blood mononuclear cells (PBMCs) of pediatric atopic dermatitis patients. We examined the molecular targets of vitamin K2 to suppress proliferation and cytokine production in T-cell mitogen-activated PBMCs of atopic dermatitis patients from the viewpoint of mitogen-activated protein kinase signaling molecules. The study population included 16 pediatric vitamin K2 patients and 21 healthy subjects. The effect of vitamin K2 on concanavalin A-activated PBMC proliferation was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and cell counting assays. T-helper (Th)1/Th2/Th17 cytokine profiles in plasma and PBMC-culture supernatants were analyzed by a cytometric beads array assay. Mitogen-activated protein kinase signaling molecules in concanavalin A-activated PBMCs were examined by enzyme-linked immunosorbent assay (ELISA) assays. At 10-100 µM, vitamin K2 significantly suppressed the proliferation of mitogen-activated PBMCs derived from atopic dermatitis patients and healthy subjects (p < 0.05). The interleukin (IL)-10 concentrations in plasma and the PBMC culture supernatants of atopic dermatitis patients were significantly higher than those of healthy subjects (p < 0.05). The IL-2 concentrations in the culture supernatants of atopic dermatitis PBMCs were significantly lower than those of healthy PBMCs (p < 0.05). Vitamin K2 significantly inhibited the IL-17A, IL-10, and tumor necrosis factor α (TNF-α) production (p < 0.05), and increased the IL-2 production (p < 0.01) in the culture supernatant of atopic dermatitis PBMCs. At 10-100 µM, vitamin K2 markedly decreased the of Mek1, extracellular signal-regulated kinases (ERK)1/2 mitogen-activated protein kinase, and SAPK/c-Jun N-terminal kinase (JNK) expression in atopic dermatitis PBMCs (p < 0.05). Vitamin K2 is suggested to attenuate activated T-cell immunity in atopic dermatitis patients through the inhibition of mitogen-activated protein kinase-Mek1-ERK1/2 and SAPK/JNK signaling pathways.

Gut Microbiota-Related Evidence Provides New Insights Into the Association Between Activating Transcription Factor 4 and Development of Salt-Induced Hypertension in Mice

Activating transcription factor 4 (ATF4), which regulates genes associated with endoplasmic reticulum stress, apoptosis, autophagy, the gut microbiome, and metabolism, has been implicated in many diseases. However, its mechanistic role in hypertension remains unclear. In the present study, we investigated its role in salt-sensitive hypertensive mice. Wild-type (WT) C57BL/6J mice were used to establish Atf4 knockout (KO) and overexpression mice using CRISPR-Cas9 and lentiviral overexpression vectors. Then, fecal microbiota transplantation (FMT) from Atf4 ^± mice and vitamin K₂ (VK2) supplementation were separately carried out in high-salt-diet (8% NaCl)-induced mice for 4 weeks. We found that Atf4 KO inhibited and Atf4 overexpression enhanced the increase in blood pressure and endothelial dysfunction induced by high salt intake in mice, while regulating the gut microbiota composition and VK2 expression. It was further verified that ATF4 is involved in the regulation of salt-sensitive hypertension and vascular endothelial function, which is achieved through association with gut microbiota and may be related to VK2 and different bacteria such as Dubosiella. In addition, we found that VK2 supplementation prevents the development of salt-sensitive hypertension and maintains vascular endothelial function; moreover, VK2 supplementation increases the abundance of intestinal Dubosiella and downregulates the relative expression of Atf4 in the thoracic aorta of mice. We conclude that ATF4 plays an important role in regulating gut microbiota and VK2 production, providing new insights into the association between ATF4 and development of salt-induced hypertension in mice, meanwhile contributing to the development for a new preventive strategy of hypertension.

The association of serum vitamin K2 levels with Parkinson's disease: from basic case-control study to big data mining analysis

Although it is known that inflammation is involved in Parkinson’s disease (PD) pathogenesis and vitamin K2 (VK2) has anti-inflammatory effects, to date few studies have been reported on the relationship between VK2 and PD development. Herein we presented a case-control study involving 93 PD patients and 95 healthy controls. Overall, the serum VK2 level of PD patients (3.49 ± 1.68 ng/ml) was significantly lower than that of healthy controls (5.77 ± 2.71 ng/ml). When the PD patients were stratified by disease progression, we observed that the serum VK2 level of late stage patients was further decreased to 3.15 ± 1.18 ng/ml while the serum VK2 level of early stage patients was 3.92 ± 2.09 ng/ml. Furthermore, the curve analysis showed that the serum VK2 level decreased gradually with the increment of PD Hoehn-Yahr (H-Y) stage. We also confirmed the dysregulated inflammatory responses and coagulation cascades in PD patients by public dataset, which are associated to the decreased VK2 level. In summary, we found the serum VK2 level in PD patients is lower than that in healthy controls. The decrease of VK2 level may be related to the occurrence and progression of PD by loosening the regulation of inflammatory responses and coagulation cascades signal.

[Determination of vitamin K1 and vitamin K2 in modulation milk powder by post-column reduction-high performance liquid chromatography]

A method for the determination of vitamin K₁ and vitamin K₂ in modulation milk powder was developed by high performance liquid chromatography (HPLC) coupled with post-column reduction. The samples were dissolved in water, lipase hydrolyzed, saponified with 2.5 mol/L sodium hydroxide solution and ethanol solution, extracted with n-hexane, and dissolved in methanol after concentration. The vitamin K were first separated on an Xbridge C₁₈ column and then on a zinc powder reduction column, and detected using a fluorescence detector. The excitation and emission wavelengths were 326 nm and 432 nm, respectively. An external standard method was used for quantification. The results showed that the linearities of vitamin K₁ and vitamin K₂ was in the ranges of 0.0025-2.0 μg/mL and 0.01-2.0 μg/mL, respectively, with correlation coefficients both greater than 0.999. The spiked recoveries were 80.39%-94.39% and the precisions were 0.85%-3.98%. The limits of detection of vitamin K₁ and vitamin K₂ were 0.07 μg/100 g and 0.2 μg/100 g, respectively. The limits of quantification of vitamin K₁ and vitamin K₂ were 0.2 μg/100 g and 0.8 μg/100 g, respectively. The method has high sensitivity and good repeatability, and gives accurate results. It is suitable for the analysis and determination of the vitamin K₁ and vitamin K₂ in formula milk powder.

Vitamin K2 Needs an RDI Separate from Vitamin K1

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.

MK-7 and Its Effects on Bone Quality and Strength

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.

Controlled Delivery of Curcumin and Vitamin K2 from Hydroxyapatite-Coated Titanium Implant for Enhanced in Vitro Chemoprevention, Osteogenesis, and in Vivo Osseointegration

Successful repair of critical-sized tumor-resection defects, especially in load-bearing bones, still remains a major challenge in clinical orthopedics. Titanium (Ti) implants have been increasingly used in the past few decades because of titanium's suitable mechanical properties and biocompatibility; however, it shows insufficient integration with the surrounding bone. In this study, the plasma spray technique is utilized to form homogeneous hydroxyapatite (HA) coating on the surface of the Ti implant to enhance osseointegration at the tissue-implant interface. These coated implants are loaded with curcumin and vitamin K2 to introduce chemopreventive and osteogenesis ability via controlled release of these biomolecules. The synergistic effect of these two biomolecules showed enhanced in vitro osteoblast (hFOB) cell attachment and proliferation for 11 days. Moreover, these biomolecules showed lower in vitro osteosarcoma (MG-63) cell proliferation after 3, 7, and 11 days. An in vivo study was carried out to evaluate the bone bonded zone in a rat distal femur model at an early wound healing stage of 5 days. Modified Masson Goldner staining of the tissue-implant section showed improved contact between tissue and implant in dual drug-loaded HA-coated Ti implants compared to control implants. This work presents a successful fabrication of a mechanically competent functional Ti implant with the advantages of enhanced in vitro osteoblast proliferation, osteosarcoma inhibition, and in vivo osseointegration, indicating the potential for load-bearing bone-defect repair after tumor resection.

Engineering Lactococcus lactis for Increased Vitamin K2 Production

Cheese produced with Lactococcus lactis is the main source of vitamin K2 in the Western diet. Subclinical vitamin K2 deficiency is common, calling for foods with enhanced vitamin K2 content. In this study we describe analyses of vitamin K2 (menaquinone) production in the lactic acid bacterium L. lactis ssp. cremoris strain MG1363. By cloning and expression from strong promoters we have identified genes and bottlenecks in the biosynthetic pathways leading to the long-chained menaquinones, MK-8 and MK-9. Key genes of the biosynthetic menaquinone pathway were overexpressed, singly or combined, to examine how vitamin K2 production can be enhanced. We observed that the production of the long menaquinone polyprenyl side chain, rather than production of the napthoate ring (1,4-dihydroxy-2-naphtoic acid), limits total menaquinone synthesis. Overexpression of genes causing increased ring formation (menF and menA) led to overproduction of short chained MK-3, while overexpression of other key genes (mvk and llmg_0196) resulted in enhanced full-length MK-9 production. Of two putatively annotated prenyl diphosphate synthases we pinpoint llmg_0196 (preA) to be important for menaquinone production in L. lactis. The genes mvk, preA, menF, and menA were found to be important contributors to menaquinone levels as single overexpression of these genes double and more than triple the total menaquinone content in culture. Combined overexpression of mvk, preA, and menA increased menaquinone levels to a higher level than obtained individually. When the overproducing strains were applied for milk fermentations vitamin K2 content was effectively increased 3-fold compared to the wild type. The results provide a foundation for development of strains to ferment foods with increased functional value i.e., higher vitamin K2 content.

Vitamin K2 Status and Arterial Stiffness Among Untreated Migraine Patients: A Case-Control Study

OBJECTIVE

We aimed to examine arterial stiffness and vitamin K2 status in migraine subjects by comparison to controls.

BACKGROUND

Migraine is a primary headache disorder that has been associated with an increased risk of cardiovascular events. Mechanisms underlying this increased risk, however, remain unclear. Vitamin K2 deficiency emerged as a cardiovascular risk factor, but vitamin K2 status has never been explored in migraine subjects.

DESIGN AND METHODS

This is a case-control, single-center, observational study that includes a cohort of subjects with migraine and their age- and sex-matched controls. Arterial stiffness was measured using carotid-femoral pulse wave velocity (cfPWV). Dephosphorylated-uncarboxylated matrix-Gla-protein (dp-ucMGP) was used as a marker for vitamin K2 status. A propensity-matched scoring method was used.

RESULTS

A total of 146 patients (73 matched pairs) were included in this study, of whom 89% were women with a mean age of 31.9 ± 8.4 years. Compared with controls, migraine patients had statistically significantly higher mean cfPWV (7.2 ± 1.1 vs 6.4 ± 0.8 m/s, 95% confidence interval (CI) of mean difference [0.45, 1.08], P < .001), as well as higher dp-ucMGP (454.3 ± 116.7 pmol/L vs 379.8 ± 126.6 pmol/L, 95% CI of mean difference [34.63, 114.31], P < .001). Higher cfPWV was associated with higher dp-ucMGP concentrations only in the migraine with aura (MWA) group. Moreover, migraine subjects had a higher frequency of vitamin K2 deficiency (dp-ucMGP ≥ 500 pmol/L) compared to controls, but this association was not statistically significant (23/73 [31.5%] vs 16/73 [21.9%], P = .193).

CONCLUSIONS

Individuals with migraine have worse indices of arterial stiffness as compared with their age- and sex-matched control subjects. This increase in arterial stiffness is associated with an increase in markers of vitamin K2 deficiency in the MWA group.

Cheese and Healthy Diet: Associations With Incident Cardio-Metabolic Diseases and All-Cause Mortality in the General Population

Background: Many countries have established Food-Based Dietary Guidelines (FBDG). For some foods, such as cheese, there is no consensus on whether or not to include them in these guidelines. Cheese may, however, be an excellent source of vitamin K2, which is a macronutrient with demonstrated positive results on cardiovascular-related outcomes.

Aim: First, we assessed the role of cheese within the recently developed Lifelines Diet Score (LLDS), a score based on the Dutch FBDG 2015 in relation to incident cardio-metabolic diseases and all-cause mortality. Secondly, we assessed the association of cheese intake with desphospho-uncarboxylated matrix Gla protein (dp-ucMGP), a marker for functional vitamin K2 status, in a subset of the population.

Methods: From the Lifelines cohort study, 122,653 adult participants were included to test the association between de LLDS and health outcomes. In a subset of 1,059 participants aged 60–75 years, dp-ucMGP levels were measured. Dietary intake was assessed using a 110-item Food Frequency Questionnaire. Logistic regression were applied, adjusted for relevant confounders.

Results: Median cheese intake was 23.5 [12.6–40.6] g/day. We found a positive correlation between cheese intake and the LLDS (Spearman's rho = 0.024, p < 0.001). The LLDS in quintiles was associated with T2DM [OR (95% CI) Q5 (healthy diet) vs. Q1 (poor diet) = 0.54 (0.43–0.67)] and all-cause mortality [Q5 vs. Q1 = 0.62 (0.50–0.76)]. Inclusion of cheese did not alter these associations. Additionally, we found no significant association of total cheese intake with plasma dp-ucMGP levels.

Conclusion: In this population-based cohort study, the inclusion of cheese in the LLDS did not change the inverse associations with incident cardio-metabolic diseases and all-cause mortality. Furthermore, we found no significant association of total cheese intake with plasma dp-ucMGP. The results suggest that cheese is a neutral food group that fits a healthy diet.

Vitamin K2 immunosuppressive effect on pediatric patients with atopic dermatitis

BACKGROUND

Over 20 kinds of steroids, tacrolimus ointments, and cyclosporine capsules are usually recommended for the treatment of atopic dermatitis (AD), depending on the symptoms of patients. However, several side effects sometimes occur with the extensive use of these agents for the treatment of pediatric AD patients. The purpose of this study was to explore whether vitamin K₂ could be a new immunosuppressive candidate for pediatric patients with AD.

METHODS

The immunosuppressive efficacy of vitamin K₂ was evaluated through a cell-culture procedure using mitogen-activated peripheral blood mononuclear cells (PBMCs) obtained from pediatric AD patients.

RESULTS

The mean (SD) IC₅₀ value of vitamin K₂ for the proliferation of concanavalin A-activated PBMCs was 15.37 (30.05) μmol/L, while the value for tacrolimus was 0.10 (0.28) ng/mL (0.12 (0.35) nmol/L). There was a significant correlation between the IC₅₀ values for vitamin K₂ and those for tacrolimus (P = 0.0001, r = 0.8871). However, there was no significant correlation between the IC₅₀ values of vitamin K₂ and those of cyclosporine A or methylprednisolone. A significant correlation between the IC₅₀ values of vitamin K₂ or tacrolimus and blood eosinophil counts (P = 0.0099, r = 0.7086 and P = 0.0032, r = 0.7722, respectively) was observed.

CONCLUSION

Vitamin K₂ -inhibited T-cell mitogen stimulated proliferation of PBMCs from pediatric AD patients in a dose-dependent manner. The PBMCs from pediatric AD patients were more sensitive to the immunosuppressive efficacy of vitamin K₂ than the PBMCs from healthy subjects. The individual immunosuppressive pharmacological efficacy of vitamin K₂ and of tacrolimus could be inferred from the blood eosinophil count of pediatric AD patients.

Metabolic biomarker signature for predicting the effect of neoadjuvant chemotherapy of breast cancer

Background

The effect of breast cancer neoadjuvant chemotherapy (NCT) is strongly associated with breast cancer long term survival, especially when patients get a pathological complete response (PCR). It always is still unknown which patient is the potential one to get a PCR in the NCT. Thus, we have seeded blood-derived metabolite biomarkers to predict the effect of NCT of breast cancer.

Methods

Patients who received either 6 or 8 cycles of anthracycline-docetaxel-based NCT (EC-T or TEC) had been assessed their response to chemotherapy-partial response (PR) (n=19) and stable disease (SD) (n=16). The serum samples had been collected before and after chemotherapy. Sixty-nine subjects were prospectively recruited with PR and SD patients before and after chemotherapy separately. Metabolomics profiles of serum samples were generated from 3,461 metabolites identified by liquid chromatography-mass spectrometry (LC-MS).

Results

Based on LC-MS metabolic profiling methods, nine metabolites were identified in this study: prostaglandin C1, ricinoleic acid, oleic acid amide, ethyl docosahexaenoic, hulupapeptide, lysophosphatidylethanolamine 0:0/22:4, cysteinyl-lysine, methacholine, and vitamin K2, which were used to make up a receiver operating characteristics (ROC) curve, a model for predicting chemotherapy response. With an area under the curve (AUC) of 0.957, the model has a specificity of 100% and sensitivity of 81.2% for predicting the response of PR and SD of breast cancer patients.

Conclusions

A model with such good predictability would undoubtedly verify that the serum-derived metabolites be used for predicting the effect of breast cancer NCT. However, how identified metabolites work for prediction is still to be clearly understood.

Vitamin K: Double Bonds beyond Coagulation Insights into Differences between Vitamin K1 and K2 in Health and Disease

Vitamin K is an essential bioactive compound required for optimal body function. Vitamin K can be present in various isoforms, distinguishable by two main structures, namely, phylloquinone (K1) and menaquinones (K2). The difference in structure between K1 and K2 is seen in different absorption rates, tissue distribution, and bioavailability. Although differing in structure, both act as cofactor for the enzyme gamma-glutamylcarboxylase, encompassing both hepatic and extrahepatic activity. Only carboxylated proteins are active and promote a health profile like hemostasis. Furthermore, vitamin K2 in the form of MK-7 has been shown to be a bioactive compound in regulating osteoporosis, atherosclerosis, cancer and inflammatory diseases without risk of negative side effects or overdosing. This review is the first to highlight differences between isoforms vitamin K1 and K2 by means of source, function, and extrahepatic activity.

The effects of vitamin K1 and vitamin K2 on the proliferation, cytokine production and regulatory T-cell frequency in peripheral blood mononuclear cells of paediatric atopic dermatitis patients

We estimated the pharmacological efficacy of vitamin K₁ (VK₁ ) and VK₂ on the mitogen-activated peripheral blood mononuclear cells (PBMCs) of paediatric atopic dermatitis (AD) patients. VK₂ suppressed the in vitro proliferation of T-cell mitogen-activated PBMCs of AD patients. In contrast, VK₁ had little effect on the PBMC proliferation. The IL-2 production from the activated PBMCs of AD patients significantly increased (P < .05), while the production significantly decreased by 100 μmol L^-1 VK₂ (P < .01). In addition, 100 μmol L^-1 VK₂ reduced the percentage of CD4+ and CD4+CD25+ cells in PBMCs. These results suggest that VK2 can modulate T-cell function in PBMCs of AD patients.

Analysis of Menaquinone-7 Content and Impurities in Oil and Non-Oil Dietary Supplements

Rapid, global technological development has caused the food industry to use concentrated food component sources like dietary supplements ever more commonly as part of the human diet. This study analysed the menaquinone-7 (MK-7) content of dietary supplements in oil capsule and hard tablet forms. A novel method for separating and measuring geometric isomers of MK-7 in dietary supplements was developed and validated. Eleven different isomers of cis/trans- menaquinone-7 were identified. Identification of cis/trans isomers was performed by combination of HPLC, UPLC and HRMS-QTOF detection, whereas their quantities were determined by DAD detection. The content of menaquinone impurities was ascertained, including cis/trans- menaquinone-6 isomers (5.5–16.9 µg per tablet/capsule) and cis/trans-menaquinone-7 isomers (70.9–218.7 µg tablet/capsule), which were most likely formed during the chemical synthesis of the menaquinone-7. The all-trans MK-7 content was lower than the isomeric form and often lower than what the labels declared. A new method of quantification, developed and validated for menaquinones in oil capsules, provided on average 90% recovery and a limit of quantification (LOQ) of approximately 1 µg mL⁻¹.