Category Archives: Vitamin K

Review: Resveratrol, Inositol, Vitamin D and K for Bone and Cardiovascular Risk

Abstract

Resveratrol, inositol, vitamin D and K in the prevention of cardiovascular and osteoporotic risk: a novel approach in peri- and postmenopause.

The prevention of cardiovascular and osteoporotic risk is a topic of great importance in the peri- and postmenopausal periods. This paper reviews the role of resveratrol, inositol, vitamin D and K in the prevention of cardiovascular and osteoporotic risk in peri- and post-. The phytoestrogen-like activity of resveratrol has potential clinical implications in the gynecological practice. In particular transresveratrol inhibits low-density lipoprotein oxidation, which is a recognized risk factor for cardiovascular diseases. Resveratrol has also a documented antiplatelet effect and may prevent cardiovascular diseases inhibiting the cardiac fibroblasts proliferation. With regard to bone health, in in vitro studies resveratrol has shown activities in osteoblastic MC3T3-E1 cells. Resveratrol also interacts with vitamin D in promoting bone health. Resveratrol is considered a caloric restriction mimetic and potentially effects factors involved in the metabolic syndrome. Myo-inositol has documented in clinical studies its effectiveness in improving the metabolic syndrome in post menopausal women. Thus the supplementation with inositol and resveratrol may be useful in the prevention of insulin resistance and consequently metabolic syndrome and cardiovascular diseases risk. Finally vitamin K2 effects calcium metabolisms and subjects with higher levels of calcium in the bones tend to have a lower frequency of vascular calcifications and a lower cardiovascular risk. Vitamin K2 also has a key role in the bone homeostasis. A supplement including resveratrol, inositol, vitamin K and vitamin D offers a novel opportunity to the woman in peri- and postmenopause.

Parazzini F
Minerva Ginecol Oct 2014
PMID: 25245999

Vitamin K2 (MK-4) + D + Calcium Reduces Lifetime Probability of Fracture by 25%

Abstract

Vitamin K supplementation for the primary prevention of osteoporotic fractures: is it cost-effective and is future research warranted?

Lifetime supplementation with vitamin K, vitamin D(3), and calcium is likely to reduce fractures and increase survival in postmenopausal women. It would be a cost-effective intervention at commonly used thresholds, but high uncertainty around the cost-effectiveness estimates persists. Further research on the effect of vitamin K on fractures is warranted.
Vitamin K might have a role in the primary prevention of fractures, but uncertainties about its effectiveness and cost-effectiveness persist.
We developed a state-transition probabilistic microsimulation model to quantify the cost-effectiveness of various interventions to prevent fractures in 50-year-old postmenopausal women without osteoporosis. We compared no supplementation, vitamin D(3) (800 IU/day) with calcium (1,200 mg/day), and vitamin K(2) (45 mg/day) with vitamin D(3) and calcium (at the same doses). An additional analysis explored replacing vitamin K(2) with vitamin K(1) (5 mg/day).
Adding vitamin K(2) to vitamin D(3) with calcium reduced the lifetime probability of at least one fracture by 25%, increased discounted survival by 0.7 quality-adjusted life-years (QALYs) (95% credible interval (CrI) 0.2; 1.3) and discounted costs by $8,956, yielding an incremental cost-effectiveness ratio (ICER) of $12,268/QALY. At a $50,000/QALY threshold, the probability of cost-effectiveness was 95% and the population expected value of perfect information (EVPI) was $28.9 billion. Adding vitamin K(1) to vitamin D and calcium reduced the lifetime probability of at least one fracture by 20%, increased discounted survival by 0.4 QALYs (95% CrI -1.9; 1.4) and discounted costs by $4,014, yielding an ICER of $9,557/QALY. At a $50,000/QALY threshold, the probability of cost-effectiveness was 80% while the EVPI was $414.9 billion. The efficacy of vitamin K was the most important parameter in sensitivity analyses.
Lifetime supplementation with vitamin K, vitamin D(3), and calcium is likely to reduce fractures and increase survival in postmenopausal women. Given high uncertainty around the cost-effectiveness estimates, further research on the efficacy of vitamin K on fractures is warranted.

Gajic-Veljanoski O, Bayoumi AM, Tomlinson G, Khan K…
Osteoporos Int Nov 2012
PMID: 22398856

Genistein + EPA + DHA + Vitamin D + K1 Increases Bone Density in Postmenopausal Women

Abstract

Effect of a combination of genistein, polyunsaturated fatty acids and vitamins D3 and K1 on bone mineral density in postmenopausal women: a randomized, placebo-controlled, double-blind pilot study.

Many postmenopausal women desire non-pharmaceutical alternatives to hormone therapy for protection against osteoporosis. Soybean isoflavones, especially genistein, are being studied for this purpose. This study examined the effects of synthetic genistein in combination with other potential bone-protective dietary molecules on bone mineral density (BMD) in early postmenopausal women.
In this 6-month double-blind pilot study, 70 subjects were randomized to receive daily either calcium only or the geniVida™ bone blend (GBB), which consisted of genistein (30 mg/days), vitamin D3 (800 IU/days), vitamin K1 (150 μg/days) and polyunsaturated fatty acids (1 g polyunsaturated fatty acids as ethyl ester: eicosapentaenoic acid/docosahexaenoic acid ratio = ~2/1). Markers of bone resorption and formation and BMD at the femoral neck, lumbar spine, Ward’s triangle, trochanter and intertrochanter, total hip and whole body were assessed.
Subjects supplemented with the GBB (n = 30) maintained femoral neck BMD, whereas in the placebo group (n = 28), BMD significantly decreased (p = 0.007). There was also a significant difference (p < 0.05) in BMD between the groups at Ward’s triangle in favor of the GBB group. Bone-specific alkaline phosphatase and N-telopeptide significantly increased in the GBB group in comparison with those in baseline and in the placebo group. The GBB was well tolerated, and there were no significant differences in adverse events between groups.
The GBB may help to prevent osteoporosis and reduce fracture risk, at least at the hip, in postmenopausal women. Larger and longer-term clinical trials are warranted.

Lappe J, Kunz I, Bendik I, Prudence K…
Eur J Nutr Feb 2013
PMID: 22302614 | Free Full Text

Review: Vitamin K2 (MK-4) Monotherapy Modestly Increases Bone Density and Reduces Fractures in Eight Studies

Abstract

Vitamin k2 therapy for postmenopausal osteoporosis.

Vitamin K may play an important role in the prevention of fractures in postmenopausal women with osteoporosis. Menatetrenone is the brand name of a synthetic vitamin K2 that is chemically identical to menaquinone-4. The present review study aimed to clarify the effect of menatetrenone on the skeleton in postmenopausal women with osteoporosis, by reviewing the results of randomized controlled trials (RCTs) in the literature. RCTs that investigated the effect of menatetrenone on bone mineral density (BMD), measured by dual-energy X-ray absorptiometry and fracture incidence in postmenopausal women with osteoporosis, were identified by a PubMed search for literature published in English. Eight studies met the criteria for RCTs. Small RCTs showed that menatetrenone monotherapy decreased serum undercarboxylated osteocalcin (ucOC) concentrations, modestly increased lumbar spine BMD, and reduced the incidence of fractures (mainly vertebral fracture), and that combined alendronate and menatetrenone therapy enhanced the decrease in serum ucOC concentrations and further increased femoral neck BMD. This review of the literature revealed positive evidence for the effects of menatetrenone monotherapy on fracture incidence in postmenopausal women with osteoporosis. Further studies are required to clarify the efficacy of menatetrenone in combination with bisphosphonates against fractures in postmenopausal women with osteoporosis.

Iwamoto J
Nutrients 2014
PMID: 24841104 | Free Full Text

One interesting passage from the full text talks about the unpublished dose range study from Japan:

Orimo, H., et al. “Clinical evaluation of soft capsule menatetrenone (Ea-0167) in the treatment of osteoporosis: late phase II dose study.” J New Remedies Clinics 41 (1992): 1249-79.

A dose-finding study of menatetrenone in Japan [7] administered daily doses of 15, 45, 90, and 135 mg and revealed that 45 mg was the minimum effective dose for improving bone mass parameters evaluated by microdensitometry and/or single photon absorptiometry in postmenopausal women with osteoporosis. This optimal dose (45 mg/day) for the treatment of osteoporosis is about 150–180 times greater than the recommended daily dietary intake of vitamin K (250–300 μg) [8]. No toxic effects of menatetrenone (45 mg/day) have been reported [7]. High-dose vitamin K is needed to prevent fractures in postmenopausal women with osteoporosis [9]. However, the effect of menatetrenone on the skeleton remains a matter of controversy [10–17], and the role of menatetrenone in the treatment of osteoporosis therefore needs to be clarified.

Vitamin K1 and K2 (MK-4, MK-7) Don’t Prevent Bone Loss in Rats Fed Adequate Nutrients

Abstract

Vitamin K supplementation does not prevent bone loss in ovariectomized Norway rats.

Despite plausible biological mechanisms, the differential abilities of phylloquinone (PK) and menaquinones (MKn) to prevent bone loss remain controversial. The objective of the current study was to compare the effects of PK, menaquinone-4 (MK-4) and menaquinone-7 (MK-7) on the rate of bone loss in ovariectomized (OVX) Norway rats. A secondary aim was to compare the effects of vitamin K with those of bisphosphonates (BP) on bone loss.
Rats (n = 96) were randomized to 6 dosing groups [n = 16/group; Sham; OVX; OVX + BP (100 μg/kg/100 μg/mL saline sc); OVX + PK; OVX + MK-4; and OVX + MK-7] for 6 wk. Equimolar daily doses of 107 mg PK/kg, 147 mg MK-4/kg, and 201 mg MK-7/kg diet were provided.
BP significantly increased bone strength and bone mineral density (BMD) vs. OVX (P < 0.05). However, PK, MK-4 or MK-7 did not change bone strength or BMD compared to the OVX group. Whereas supplementation of PK, MK-4 and MK-7 increased serum and tibia concentrations of each respective form, PK concentrations were consistently higher despite equimolar intakes.
PK, MK-4, and MK-7 do not appear to prevent bone loss in OVX rats when administered concurrent with adequate intake of other nutrients.

Fu X, Moreines J, Booth SL
Nutr Metab (Lond) 2012
PMID: 22348311 | Free Full Text

In conclusion, supplementation of PK, MK-4 or MK-7 did not confer a beneficial effect on bone loss in ovariectomized Norway rats fed a diet that meets nutritional requirements for other nutrients, including calcium and vitamin D. This would suggest that equivocal findings in the literature regarding the effect of various forms of vitamin K on bone cannot be attributed to differences among the forms studied. These data are also consistent with a growing number of clinical studies that report no beneficial effect of vitamin K supplementation on bone loss in the elderly who are otherwise calcium and vitamin D-replete [1,18,19].

Vitamin K2 (MK-4) Shows Similar Effectiveness to Alfacalcidol

Abstract

Menatetrenone versus alfacalcidol in the treatment of Chinese postmenopausal women with osteoporosis: a multicenter, randomized, double-blinded, double-dummy, positive drug-controlled clinical trial.

To evaluate whether the efficacy and safety of menatetrenone for the treatment of osteoporosis is noninferior to alfacalcidol in Chinese postmenopausal women.
This multicenter, randomized, double-blinded, double-dummy, noninferiority, positive drug-controlled clinical trial was conducted in five Chinese sites. Eligible Chinese women with postmenopausal osteoporosis (N=236) were randomized to Group M or Group A and received menatetrenone 45 mg/day or alfacalcidol 0.5 μg/day, respectively, for 1 year. Additionally, all patients received calcium 500 mg/day. Posttreatment bone mineral density (BMD), new fracture onsets, and serum osteocalcin (OC) and undercarboxylated OC (ucOC) levels were compared with the baseline value in patients of both groups.
A total of 213 patients (90.3%) completed the study. After 1 year of treatment, BMD among patients in Group M significantly increased from baseline by 1.2% and 2.7% at the lumbar spine and trochanter, respectively (P<0.001); and the percentage increase of BMD in Group A was 2.2% and 1.8%, respectively (P<0.001). No difference was observed between groups. There were no changes in femoral neck BMD in both groups. Two patients (1.9%, 2/108) in Group M and four patients (3.8%, 4/105) in Group A had new fracture onsets (P>0.05). In Group M, OC and ucOC decreased from baseline by 38.7% and 82.3%, respectively (P<0.001). In Group A, OC and ucOC decreased by 25.8% and 34.8%, respectively (P<0.001). Decreases in serum OC and ucOC were more obvious in Group M than in Group A (P<0.001). The safety profile of menatetrenone was similar to alfacalcidol.
Menatetrenone is an effective and safe choice in the treatment of postmenopausal osteoporosis in Chinese women.

Jiang Y, Zhang ZL, Zhang ZL, Zhu HM…
Clin Interv Aging 2014
PMID: 24426779 | Free Full Text

Vitamin K2 (MK4) Inhibits Bone Resorption Through Inhibition of PGE2 In Vitro

Abstract

Menatetrenone inhibits bone resorption partly through inhibition of PGE2 synthesis in vitro.

We studied the effect of menatetrenone, a vitamin K2 homolog, on bone resorption stimulated by interleukin-1 alpha (IL-1 alpha), prostaglandin E2 (PGE2), parathyroid hormone (PTH), and 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3]. Bone-resorbing activity was assessed by measurement of calcium and hydroxyproline in the media and calvariae. IL-1 alpha (0.1-100 U/ml), 1,25-(OH)2D3 (10(-10)-10(-7) M), PGE2 (10(-9)-10(-6) M), and PTH (3 x 10(-8)-3 x 10(-7) M) dose dependently increased the levels of calcium and hydroxyproline in the medium. Indomethacin (10(-6) M) completely inhibited bone resorption induced by IL-1 alpha and partially inhibited bone resorption induced by 1,25-(OH)2D3. However, indomethacin did not affect the action of PGE2 or PTH. Menatetrenone (3 x 10(-6)-3 x 10(-5) M) inhibited the bone resorption induced by IL-1 alpha (2 U/ml), PGE2 (10(-7) M), PTH (3 x 10(-7) M), and 1,25-(OH)2D3 (3 x 10(-10) M) in a dose-dependent manner. Menatetrenone also inhibited the PGE2 production stimulated by IL-1 alpha. These results indicate that menatetrenone may inhibit bone resorption through at least two different mechanisms; one possibly is an inhibitory effect on prostaglandin production.

Hara K, Akiyama Y, Tajima T, Shiraki M
J. Bone Miner. Res. May 1993
PMID: 8511981

Vitamin K Intake Not Associated with Fracture in Chinese Men and Women

Abstract

No association between dietary vitamin K intake and fracture risk in chinese community-dwelling older men and women: a prospective study.

Data on the association between dietary vitamin K intake and fracture risk are limited among Chinese. This study examined such an association in community-dwelling elderly in Hong Kong. We present data from 2,944 subjects (1,605 men, 1,339 women) who participated in a prospective cohort study. Baseline dietary intakes of energy, protein, calcium, vitamin D, and vitamin K were assessed using a food-frequency questionnaire. Data on incident hip fracture and nonvertebral fracture during a median of 6.9 follow-up years were collected from a hospital database. Cox regression analyses were performed with adjustments for age, education attainment, smoking status, alcohol use, body mass index, hip bone mineral density, physical activity, use of calcium supplement, and energy-adjusted nutrient intakes. There were 29 (1.8 %) men and 19 (1.4 %) women with incident hip fractures and 97 (6.0 %) men and 88 (6.6 %) women with nonvertebral fractures. The median (interquartile range) of dietary vitamin K intake was 241.8 (157.5-360.8) and 238.9 (162.4-343.6) μg/day in men and women, respectively. Similar dietary vitamin K intakes were observed between subjects with hip or nonvertebral fractures and subjects without hip or nonvertebral fractures. In both men and women, dietary vitamin K intake was not associated with fracture risks at all measured sites in either crude or adjusted models. In Chinese community-dwelling elderly, hip or nonvertebral fracture risk was not associated with dietary vitamin K intake. The high dietary vitamin K intake of the studied group may have limited the ability to detect the association between vitamin K intake and fracture risk.

Chan R, Leung J, Woo J
Calcif. Tissue Int. May 2012
PMID: 22451220

Low Vitamin K May Increase Hip Fracture in Women

Abstract

Vitamin K intake and hip fractures in women: a prospective study.

Vitamin K mediates the gamma-carboxylation of glutamyl residues on several bone proteins, notably osteocalcin. High serum concentrations of undercarboxylated osteocalcin and low serum concentrations of vitamin K are associated with lower bone mineral density and increased risk of hip fracture. However, data are limited on the effects of dietary vitamin K. We investigated the hypothesis that high intakes of vitamin K are associated with a lower risk of hip fracture in women.
We conducted a prospective analysis within the Nurses’ Health Study cohort. Diet was assessed in 72327 women aged 38-63 y with a food-frequency questionnaire in 1984 (baseline). During the subsequent 10 y of follow-up, 270 hip fractures resulting from low or moderate trauma were reported.
Women in quintiles 2-5 of vitamin K intake had a significantly lower age-adjusted relative risk (RR: 0.70; 95% CI: 0.53, 0.93) of hip fracture than women in the lowest quintile (< 109 microg/d). Risk did not decrease between quintiles 2 and 5 and risk estimates were not altered when other risk factors for osteoporosis, including calcium and vitamin D intakes, were added to the models. Risk of hip fracture was also inversely associated with lettuce consumption (RR: 0.55; 95% CI: 0.40, 0.78) for one or more servings per day compared with one or fewer servings per week), the food that contributed the most to dietary vitamin K intakes.
Low intakes of vitamin K may increase the risk of hip fracture in women. The data support the suggestion for a reassessment of the vitamin K requirements that are based on bone health and blood coagulation.

Feskanich D, Weber P, Willett WC, Rockett H…
Am. J. Clin. Nutr. Jan 1999
PMID: 9925126 | Free Full Text

Review: Vitamin K Reviewed by European Vitamin K Experts

Abstract

Beyond deficiency: potential benefits of increased intakes of vitamin K for bone and vascular health.

Vitamin K is well known for its role in the synthesis of a number of blood coagulation factors. During recent years vitamin K-dependent proteins were discovered to be of vital importance for bone and vascular health. Recommendations for dietary vitamin K intake have been made on the basis of the hepatic requirements for the synthesis of blood coagulation factors. Accumulating evidence suggests that the requirements for other functions than blood coagulation may be higher. This paper is the result of a closed workshop (Paris, November 2002) in which a number of European vitamin K experts reviewed the available data and formulated their standpoint with respect to recommended dietary vitamin K intake and the use of vitamin K-containing supplements.

Vermeer C, Shearer MJ, Zittermann A, Bolton-Smith C…
Eur J Nutr Dec 2004
PMID: 15309455 | Free Full Text

Accumulating evidence suggests that in many aspects arterial calcification mimics bone formation, which prompts interest in the effects of vitamin K on the vasculature. Previous population-based studies reported a significant reduction in aortic calcification with high vitamin K1 [62] and vitamin K2 intake [63], and a significant inverse correlation was found between vitamin K2 intake, and the incidence of both ischaemic heart disease and cardiovascular mortality [63]. Based on these findings the effect of treatment on arterial characteristics was monitored in the Maastricht osteostudy. These unpublished findings clearly demonstrated that supplementation with vitamin K1 can protect against vascular hardening and loss of arterial elasticity. High dose MK-4 also seems to have cholesterol lowering properties as shown in studies in rabbits [64] and humans [65].

[…]

Extremely high doses (45–90mg/day) of MK-4 have been used for the treatment of postmenopausal osteoporosis in Japan for several years [66, 67]. After the positive outcomes of the first clinical trials, the treatment is now used on a large scale; thus far, no adverse side-effects have been reported. A number of independent groups have claimed that this medication results in complete prevention of further bone loss in postmenopausal women, and in some women even a significant gain in BMD [68, 69]. The treatment was also reported to be successful in other groups at risk for bone loss such as haemodialysis patients and those treated with corticosteroids.

[…]

In considering the potential efficacy of pharmacological doses of MK-4 it should be noted that there is evidence for a secondary function of this analogue over and above its role in glutamate carboxylation. The available evidence (mainly from cell culture experiments) suggests that MK-4 (but not K1) may also be associated with production of interleukin-6, regulate the synthesis of PGE2 [83], or inhibit the mevalonate pathway in a comparable way to bisphosphonates [84], but at present only preliminary data exist.

[…]

Any risks associated with relatively high consumption of either K1 or K2 appear minimal, with intakes up to 1 mg/d K1 and 45 mg/d MK-4 often having been used without observed adverse events. Two possible exceptions exist. Firstly a potential problem relates to interference with oral anticoagulants. However, a systematic dose-response study among subjects on oral anticoagulant treatment demonstrated that the stability of anticoagulation was not significantly affected by vitamin K supplements at doses below 100 μg/day [14]. Secondly, preliminary studies have suggested that high vitamin K1 supplementation (i. e. above 1 mg/day) can contribute to periodontal disease via a bacterial mechanism on gingival tissue (S. Hodges, unpublished data).