**Author details**

Fermented dairy products are vital for bone health because of their unique combination of various nutrients and microorganisms that support and maintain positive bone metabolism [57, 60]. Additionally, dairy matrix and nutrient composition may affect the delivery of

**11. Cardiovascular health, menaquinones, and fermented dairy products**

Coronary artery calcification (CAC) is a predictor of cardiovascular disease (CVD) and mortality. Based on vitamin K's role in activating matrix Gla protein (MGP), a calcification inhibitor, vitamin K is proposed to play a preventive role in CAC and CVD [59, 62]. As recently reviewed, randomized controlled trials that examined the influence of vitamin K on the risk of cardiovascular disease are scarce [63]. The results of observational studies have shown an association between higher dietary menaquinone consumption and less calcification [64], decreased risk of coronary heart disease (CHD), CHD mortality, and all‐cause mortality [65– 67]. The results of a Dutch prospective cohort study suggested that of all MKs the long‐chain menaquinones (MK‐7 to MK‐9) have the most beneficial effects on cardiovascular disease [67]. Although these results are promising, they must be interpreted with caution, because validated

Complex milk fatty acid chemistry and several minerals, such as calcium, magnesium, phosphorus, and potassium provided in relevant concentrations, have been proposed to be involved in the complex mechanism of dairy products and their support to reduce CVD risk [68]. Among the high number of different fatty acids in dairy products, trans‐palmitoleic acid, stearic acid, lauric acid, myristic acid, and oleic acid have been associated with beneficial effects on blood lipids and serum lipoprotein levels [56]. These assumptions are supported by the inverse association observed between CHD risk and the consumption of milk, cheese, and meat

Our knowledge of the consumption of menaquinones should be improved with weighed and extended food records [51] in combination with (multiple) biomarkers in the blood for vitamin K status [52] and the content of the various menaquinones in food items such as cheese, which

As different lactic acid bacteria strains used in cheese production influence the expression of various MKs, analysis of a wide variety of different cheeses may be necessary for a represen‐ tative overview of the vitamin K2 content in this food group. Although results from well‐ designed clinical trials investigating the association between menaquinones and bone health, as well as cardiovascular health, are rare, dairy products seem to be predestined to play a major role in the Western diet because of their nutrient density and matrix properties that improve

menaquinones and improve vitamin K status [61].

76 Vitamin K2 - Vital for Health and Wellbeing

biomarkers for single MK intake are missing [16].

as the richest sources of MKs in the Western diet [6, 67].

contribute most to the supply with this vitamin.

the bioavailability of vitamin K2.

**12. Conclusion**

Barbara Walther\* and Magali Chollet

\*Address all correspondence to: barbara.walther@agroscope.admin.ch

Federal Department of Economic Affairs, Education and Research EAER Agroscope, Institute for Food Sciences IFS, Berne, Switzerland

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www.lmreview.com/articles/view/Vitamin-K2-Essential-for-Prevention-of-Age-Associated-Chronic-Disease/[Accessed:2016-05-18]

**Chapter 5**

**Provisional chapter**

**The Impact of Vitamin K2 on Energy Metabolism**

Environmental and behavioral adaptations introduced during the last decades have synergistically enhanced man's lifespan, but also paved the ground for disease states involving impairment of multiple organs, which are both modulating and depending on

Diabetes, obesity, and/or bone brittleness now occur frequently in our society, inducing ailments affecting overall health and well-being. Therefore, an improved comprehension of how organs (e.g. bone and adipose tissue) may provide homeostasis and sound strategies to treat these diseases, thus improving health and life quality of most age categories, should be sought. The steroid and xenobiotic receptor (SXR) (pregnane X receptor = PXR) is a nuclear steroid-like hormone receptor, stimulated by hormones, steroids, drugs, and xenobiotic compounds. SXR exhibits a versatile ligand binding domain, serving as a xenobiotic sensor, regulating xenobiotic clearance from the liver and intestine. However, new and interesting functions of SXR in the regulation of inflammatory processes, cholecalciferol and bone metabolism, lipid and energy homeostasis, and cancer therapy, have emerged. Hence, the discovery and pharmacological development of new PXR modulators, like vitamin K2, represent an interesting and innovative therapeutic approach to combat various diseases, of which glucose and lipid metabolism (i.e., energy metabolism and

**The Impact of Vitamin K2 on Energy Metabolism**

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

© 2017 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

and reproduction in any medium, provided the original work is properly cited.

In the past years, we have seen a plethora of research reports illuminating the link between bone physiology and energy metabolism, even though the central and sympathetic nervous

Mona Møller, Serena Tonstad, Tone Bathen and

Additional information is available at the end of the chapter

homeostatic calorie "accounting."

adiposity) should be emphasized.

**Keywords:** vitamin K2, energy metabolism, PXR, SXR

Additional information is available at the end of the chapter

Mona Møller, Serena Tonstad, Tone Bathen

Jan Oxholm Gordeladze

and Jan Oxholm Gordeladze

http://dx.doi.org/10.5772/67152

**Abstract**

**1. Introduction**


#### **The Impact of Vitamin K2 on Energy Metabolism The Impact of Vitamin K2 on Energy Metabolism**

Mona Møller, Serena Tonstad, Tone Bathen and Jan Oxholm Gordeladze Mona Møller, Serena Tonstad, Tone Bathen and Jan Oxholm Gordeladze

Additional information is available at the end of the chapter Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/67152

#### **Abstract**

www.lmreview.com/articles/view/Vitamin-K2-Essential-for-Prevention-of-Age-

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[67] Gast GCM, de Roos NM, Sluijs I, Bots ML, Beulens JWJ, Geleijnse JM, et al. A high menaquinone intake reduces the incidence of coronary heart disease. Nutrition, Metabolism and Cardiovascular Diseases. 2009;19(7):504–510. DOI: 10.1016/j.numecd.

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disease: the rotterdam study. Journal of Nutrition. 2004;134(11):3100–3105.

rosclerosis. 2009;203(2):489–493. DOI: 10.1016/j.atherosclerosis.2008.07.010

Associated-Chronic-Disease/[Accessed:2016-05-18]

26. DOI: 10.1002/14651858.CD011148.pub2

10.3945/an.111.001644

82 Vitamin K2 - Vital for Health and Wellbeing

2008.10.004

Environmental and behavioral adaptations introduced during the last decades have synergistically enhanced man's lifespan, but also paved the ground for disease states involving impairment of multiple organs, which are both modulating and depending on homeostatic calorie "accounting."

Diabetes, obesity, and/or bone brittleness now occur frequently in our society, inducing ailments affecting overall health and well-being. Therefore, an improved comprehension of how organs (e.g. bone and adipose tissue) may provide homeostasis and sound strategies to treat these diseases, thus improving health and life quality of most age categories, should be sought. The steroid and xenobiotic receptor (SXR) (pregnane X receptor = PXR) is a nuclear steroid-like hormone receptor, stimulated by hormones, steroids, drugs, and xenobiotic compounds. SXR exhibits a versatile ligand binding domain, serving as a xenobiotic sensor, regulating xenobiotic clearance from the liver and intestine. However, new and interesting functions of SXR in the regulation of inflammatory processes, cholecalciferol and bone metabolism, lipid and energy homeostasis, and cancer therapy, have emerged.

Hence, the discovery and pharmacological development of new PXR modulators, like vitamin K2, represent an interesting and innovative therapeutic approach to combat various diseases, of which glucose and lipid metabolism (i.e., energy metabolism and adiposity) should be emphasized.

**Keywords:** vitamin K2, energy metabolism, PXR, SXR

#### **1. Introduction**

In the past years, we have seen a plethora of research reports illuminating the link between bone physiology and energy metabolism, even though the central and sympathetic nervous

and reproduction in any medium, provided the original work is properly cited.

© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, © 2017 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

systems, but also the gastrointestinal and pancreatic axes serve essential functions related to the systemic regulation of energy expenditure. It may be asserted that the fat tissue is more prominent due to its basic implication in storing and dissipating energy. During the last 25 years, a major progress has been communicated within the medical societies, featuring a modern understanding of the origin of fat tissues, their specialized characteristics and functioning, as well as the pathophysiological consequences of their impairment. These advances consequently lead to the discovery that adipose tissue metabolism is heavily coupled to the homeostasis of the skeleton.

has been shown to protect mice from diet-induced obesity and metabolic dysfunction [9]. Furthermore, ablation of beige fat cells by adipocyte-only deletion of the transcriptional modulator PRDM16, yields experimental animals, which become prone to diet-induced

The Impact of Vitamin K2 on Energy Metabolism

http://dx.doi.org/10.5772/67152

85

In line with the cited article published by Lecka-Czernik et al. in Archives of Biochemistry and Biophysics, 2014 [13], we performed the following experiment: Human adipose stem cells and 3T3-L1 preadipocytes, the latter with an activated mutation (ref) in the Gi2α-protein were differentiated into fully mature adipocytes as indicated by coloration with Alizarin Red. Interestingly, both adipocyte species accumulated triglycerides upon differentiation to mature adipocytes; however, exposure to vitamin K2 (MK-7) diminished their ability to turn into fully mature adipocytes. Furthermore, both adipocyte species were tested for expression of various genes differing white adipocytes from beige adipocytes. From the gene expression profile, featuring genes like the beta-adrenergic receptor β3-AR, Foxc2, PGC1α, PPARα, Dio2, UCP1, Adipoq, and Leptin, it was quite obvious that the preadipocytes in question differentiated more in the "direction" of beige, lipid (or fatty acid) metabolizing adipocytes than into white, triglyceride-storing adipocytes. Hence, it could be concluded or hypothesized that vitamin K2 (MK-7), in fact, was able to direct preadipocytes into becoming an energy-dissipating, rather than energy-storing adipocyte phenotype (see **Figure 1**, left and right panels). A putative model featuring this development, referring to a suggested mecha-

Here, we have demonstrated that vitamin K2 affects the differentiation of preadipocytes to mature adipocytes, ensuring that the "end-point" phenotype may be tilted in the direction of the beige, energy "dissipating" phenotype. In their paper from 2014, Lecka-Czernik and coworkers [13] assert that an impairment in fat function correlates with a reduced bone mass and an increased incidence of fractures. But, the question posed by the authors is: does accumulation of bone marrow adipose tissue (BMAT) exert a detrimental effect on bone structure and or mineralization, and will a diminished bone mass stimulate the accumulation of BMAT? Historically, BMAT was construed as a dormant or inert type of fat that accumulated within the bone marrow in order to pose as empty space filling subsequent to involution of hematopoietic tissue. Hence, its relationship with a lower bone mass was construed as circumstantial. However, novel evidence asserted that marrow adipogenesis should be construed as a process, which is tightly bound to the differentiation of osteoblasts, since they "share" common precursor cells, and they are subjected to same modulatory signaling patterns. This yields, however, opposite end results where a positive correlation with an overall fat metabolism

indicates that BMAT, in fact, actively induces bone mass loss and inferior quality.

Both, over and malnutrition represent systemic changes in energy metabolism, affecting bone fat volume and bone mass. Despite the fact that adipose (overweight) individuals present with a higher body weight, the more often than not demonstrate a lower BMD. In obese older men and women, an enhanced percentage of body fat and low amount of lean (muscle) mass predicts a lower BMD and thus an enhanced frailty risk [14]. The enhanced fracture risk incurred by postmenopausal women and older men [15] is mainly due to enhanced circulatory levels of adipose tissue derived in adiponectin and proinflammatory cytokines, with a concomitant

obesity and ensuing insulin resistance [12].

nism, is given in **Figure 2**.

Fat tissue is able to deposit and releases energy rich compounds during feeding and fasting, respectively, and it modulates the energy homeostasis in a versatility of organs via its endocrine potential. Fat cells (adipocytes) may accumulate energy in the form of triglycerides, as well as burning it by degrading fatty acids via so-called β-oxidation. Additionally, adipocytes produce and release so-called adipokines, among which leptin and adiponectin are the most important ones. These hormones regulate both the ingestion of calories, as well as the body's sensitivity to insulin. The functional multiplicity of adipose tissue is sustained by various subtypes of adipocytes in depot storing fat. Mitochondria-sparse white adipose tissue (WAT), characterized as visceral and subcutaneous fat, stores energy as triglycerides for which the level is regulated by the body's sensitivity to insulin and the overall metabolism of glucose in the liver and skeletal muscle cells, respectively. Contrastingly, mitochondria-enriched brown adipose tissue (BAT), which in adults is positioned as discrete entities localized in the neck and other regions of the trunk of the body [1], serves to dissipate energy to sustain adaptive thermogenesis [2]. This process is facilitated by the action of uncoupling protein 1 (UCP1), stimulating a leakage of protons, in order to uncouple respiration from ATP synthesis, thus favoring heat production. The thermogenesis sustained by BAT is mastered via the central nervous system, the impact of both the signaling systems comprised by catecholamines (i.e., β-adrenergic signaling), as well as deiodinase 2 (Dio2)-facilitated thyroid hormone conversion from T4 (thyroxine) to T3 (triiodothyronine). As an extra feature, compared to its role in adaptive thermogenesis, BAT is also protecting against obesity, as well as against insulin resistance and development of diabetes [5–8]. Finally, it is worth noticing that genetic ablation of BAT in small experimental animals is resulting in diet-induced obesity, diabetes mellitus with insulin resistance, as well as enhanced blood lipids [3].

It has been asserted that BAT may originate from two sources. The classical or ordinary, preformed BAT stems from Myf5-positive dermomyotomal progenitor cells which may also yield skin and muscle, as well as functioning in so-called nonshivering thermogenesis [4]. On the other hand, Myf5-negative progenitor cells may differentiate into white adipocytes which play a role in energy storage, or to BAT-like or "beige" fat cells. The latter adipocytes demonstrate both brown and white fat cell characteristics [5]. Of major importance is the fact that BAT-like adipocytes can be transformed into WAT-like adipocytes through a plethora of mechanisms, of which a few deserves mentioning; cold exposure, endocrine action of FGF21 [6] or irisin [7], and via transcriptional regulators including FoxC2 [8], PRDM16 [9], and PPARc [10], which lead to SirT1-mediated deacetylation of the PPARc protein [11]. Beige fat possesses powerful antiobesity and antidiabetic activities. An overexpression of BAT-specific transcription factors, i.e., either FoxC2 or PRDM16 in WAT adipocytes, has been shown to protect mice from diet-induced obesity and metabolic dysfunction [9]. Furthermore, ablation of beige fat cells by adipocyte-only deletion of the transcriptional modulator PRDM16, yields experimental animals, which become prone to diet-induced obesity and ensuing insulin resistance [12].

systems, but also the gastrointestinal and pancreatic axes serve essential functions related to the systemic regulation of energy expenditure. It may be asserted that the fat tissue is more prominent due to its basic implication in storing and dissipating energy. During the last 25 years, a major progress has been communicated within the medical societies, featuring a modern understanding of the origin of fat tissues, their specialized characteristics and functioning, as well as the pathophysiological consequences of their impairment. These advances consequently lead to the discovery that adipose tissue metabolism is heavily coupled to the

Fat tissue is able to deposit and releases energy rich compounds during feeding and fasting, respectively, and it modulates the energy homeostasis in a versatility of organs via its endocrine potential. Fat cells (adipocytes) may accumulate energy in the form of triglycerides, as well as burning it by degrading fatty acids via so-called β-oxidation. Additionally, adipocytes produce and release so-called adipokines, among which leptin and adiponectin are the most important ones. These hormones regulate both the ingestion of calories, as well as the body's sensitivity to insulin. The functional multiplicity of adipose tissue is sustained by various subtypes of adipocytes in depot storing fat. Mitochondria-sparse white adipose tissue (WAT), characterized as visceral and subcutaneous fat, stores energy as triglycerides for which the level is regulated by the body's sensitivity to insulin and the overall metabolism of glucose in the liver and skeletal muscle cells, respectively. Contrastingly, mitochondria-enriched brown adipose tissue (BAT), which in adults is positioned as discrete entities localized in the neck and other regions of the trunk of the body [1], serves to dissipate energy to sustain adaptive thermogenesis [2]. This process is facilitated by the action of uncoupling protein 1 (UCP1), stimulating a leakage of protons, in order to uncouple respiration from ATP synthesis, thus favoring heat production. The thermogenesis sustained by BAT is mastered via the central nervous system, the impact of both the signaling systems comprised by catecholamines (i.e., β-adrenergic signaling), as well as deiodinase 2 (Dio2)-facilitated thyroid hormone conversion from T4 (thyroxine) to T3 (triiodothyronine). As an extra feature, compared to its role in adaptive thermogenesis, BAT is also protecting against obesity, as well as against insulin resistance and development of diabetes [5–8]. Finally, it is worth noticing that genetic ablation of BAT in small experimental animals is resulting in diet-induced obesity, diabetes mellitus

It has been asserted that BAT may originate from two sources. The classical or ordinary, preformed BAT stems from Myf5-positive dermomyotomal progenitor cells which may also yield skin and muscle, as well as functioning in so-called nonshivering thermogenesis [4]. On the other hand, Myf5-negative progenitor cells may differentiate into white adipocytes which play a role in energy storage, or to BAT-like or "beige" fat cells. The latter adipocytes demonstrate both brown and white fat cell characteristics [5]. Of major importance is the fact that BAT-like adipocytes can be transformed into WAT-like adipocytes through a plethora of mechanisms, of which a few deserves mentioning; cold exposure, endocrine action of FGF21 [6] or irisin [7], and via transcriptional regulators including FoxC2 [8], PRDM16 [9], and PPARc [10], which lead to SirT1-mediated deacetylation of the PPARc protein [11]. Beige fat possesses powerful antiobesity and antidiabetic activities. An overexpression of BAT-specific transcription factors, i.e., either FoxC2 or PRDM16 in WAT adipocytes,

with insulin resistance, as well as enhanced blood lipids [3].

homeostasis of the skeleton.

84 Vitamin K2 - Vital for Health and Wellbeing

In line with the cited article published by Lecka-Czernik et al. in Archives of Biochemistry and Biophysics, 2014 [13], we performed the following experiment: Human adipose stem cells and 3T3-L1 preadipocytes, the latter with an activated mutation (ref) in the Gi2α-protein were differentiated into fully mature adipocytes as indicated by coloration with Alizarin Red. Interestingly, both adipocyte species accumulated triglycerides upon differentiation to mature adipocytes; however, exposure to vitamin K2 (MK-7) diminished their ability to turn into fully mature adipocytes. Furthermore, both adipocyte species were tested for expression of various genes differing white adipocytes from beige adipocytes. From the gene expression profile, featuring genes like the beta-adrenergic receptor β3-AR, Foxc2, PGC1α, PPARα, Dio2, UCP1, Adipoq, and Leptin, it was quite obvious that the preadipocytes in question differentiated more in the "direction" of beige, lipid (or fatty acid) metabolizing adipocytes than into white, triglyceride-storing adipocytes. Hence, it could be concluded or hypothesized that vitamin K2 (MK-7), in fact, was able to direct preadipocytes into becoming an energy-dissipating, rather than energy-storing adipocyte phenotype (see **Figure 1**, left and right panels). A putative model featuring this development, referring to a suggested mechanism, is given in **Figure 2**.

Here, we have demonstrated that vitamin K2 affects the differentiation of preadipocytes to mature adipocytes, ensuring that the "end-point" phenotype may be tilted in the direction of the beige, energy "dissipating" phenotype. In their paper from 2014, Lecka-Czernik and coworkers [13] assert that an impairment in fat function correlates with a reduced bone mass and an increased incidence of fractures. But, the question posed by the authors is: does accumulation of bone marrow adipose tissue (BMAT) exert a detrimental effect on bone structure and or mineralization, and will a diminished bone mass stimulate the accumulation of BMAT? Historically, BMAT was construed as a dormant or inert type of fat that accumulated within the bone marrow in order to pose as empty space filling subsequent to involution of hematopoietic tissue. Hence, its relationship with a lower bone mass was construed as circumstantial. However, novel evidence asserted that marrow adipogenesis should be construed as a process, which is tightly bound to the differentiation of osteoblasts, since they "share" common precursor cells, and they are subjected to same modulatory signaling patterns. This yields, however, opposite end results where a positive correlation with an overall fat metabolism indicates that BMAT, in fact, actively induces bone mass loss and inferior quality.

Both, over and malnutrition represent systemic changes in energy metabolism, affecting bone fat volume and bone mass. Despite the fact that adipose (overweight) individuals present with a higher body weight, the more often than not demonstrate a lower BMD. In obese older men and women, an enhanced percentage of body fat and low amount of lean (muscle) mass predicts a lower BMD and thus an enhanced frailty risk [14]. The enhanced fracture risk incurred by postmenopausal women and older men [15] is mainly due to enhanced circulatory levels of adipose tissue derived in adiponectin and proinflammatory cytokines, with a concomitant lower secretion of leptin and IGF-1. Furthermore, one will often detect lowered blood levels of 25-hydroxyvitamin D and higher serum parathyroid hormone levels in these "patients" [15].

**2. Vitamin K2 and its mechanism of action – beyond xenobiotic** 

The steroid and xenobiotic receptor (SXR), which is synonymous with the pregnane X receptor = PXR, is characterized as a nuclear hormone receptor that is stimulated by a plethora of hormones, dietary steroids, pharmaceutically active agents, as well as xenobiotic compounds. SXR exhibits a binding domain, which diverges across mammalian species. SXR is construed as a xenobiotic sensor, facilitating xenobiotic clearance in the liver and intestine. However, newly published experiments unravel novel roles for SXR in modulating phenomena like inflammation, bone turnover, metabolism of vitamin D, lipid, and energy homeostasis, as well as cancer. The characterization of SXR as conveyer of hormone-like signals has now been recognized as a key instrument for the study of novel mechanisms, through which diet may ultimately affect health and disease. The discovery and pharmacological development of new PXR modulators, like vitamin K2, might represent an interest-

**Figure 2.** Putative model system featuring the mechanism behind the impact of vitamin K2 (MK-7). Based on previously published consensus material, our new findings of the effect of vitamin K2 (MK-7) shows that K2, via binding to the transcription factor PXR/SXR affects several signaling molecules and/or pathways, via the β3-adrenergic system, impinging on signaling molecules like PKA, PGC1α, C/EBPβ, and Dio2, which eventually affects the activity of the uncoupling protein UCP1, which produces heat (and not ATP) from fatty acids. Not mentioned in the text is the reciprocal regulatory loop consisting of the microRNA species hsa-mir-155 and the transcription factor C/EBPβ, which can be manipulated to reinforce the "beige" phenotype of the adipocyte after differentiation from the stem cells or preadipocytes.

The Impact of Vitamin K2 on Energy Metabolism

http://dx.doi.org/10.5772/67152

87

ing and innovative therapeutic approach to combat various ailments and diseases.

**metabolism**

**Figure 1.** Human adipose stem cells and mutated 3T3-L1 preadipocytes were differentiated towards mature adipocytes. *Top panel*: Control cells are not manipulated with differentiating medium show lack of ability to store lipids (no Alizarin Red accumulation). Cells are differentiated in the presence of insulin, as well as IBMX (an inhibitor of phosphodiesterase) accumulate lipids, while cells are also exposed to vitamin K2 (MK-7) and lose their ability to produce and store triglycerides. *Bottom panel*: Percentage modulation relative to the "control" stage seen with exposure of human adipocytes and mutated 3T3-L1 cells to differentiating medium versus exposure to vitamin K2 (MK-7). Cells treated with vitamin K2 exhibit significant increments in genes characterizing beige adipocytes, where the alterations in PGC1α, PPARα, PPARγ, Dio2, and UCP1 expression were more prominent.

lower secretion of leptin and IGF-1. Furthermore, one will often detect lowered blood levels of 25-hydroxyvitamin D and higher serum parathyroid hormone levels in these "patients" [15].

86 Vitamin K2 - Vital for Health and Wellbeing

**Figure 1.** Human adipose stem cells and mutated 3T3-L1 preadipocytes were differentiated towards mature adipocytes. *Top panel*: Control cells are not manipulated with differentiating medium show lack of ability to store lipids (no Alizarin Red accumulation). Cells are differentiated in the presence of insulin, as well as IBMX (an inhibitor of phosphodiesterase) accumulate lipids, while cells are also exposed to vitamin K2 (MK-7) and lose their ability to produce and store triglycerides. *Bottom panel*: Percentage modulation relative to the "control" stage seen with exposure of human adipocytes and mutated 3T3-L1 cells to differentiating medium versus exposure to vitamin K2 (MK-7). Cells treated with vitamin K2 exhibit significant increments in genes characterizing beige adipocytes, where the alterations in PGC1α,

PPARα, PPARγ, Dio2, and UCP1 expression were more prominent.

**Figure 2.** Putative model system featuring the mechanism behind the impact of vitamin K2 (MK-7). Based on previously published consensus material, our new findings of the effect of vitamin K2 (MK-7) shows that K2, via binding to the transcription factor PXR/SXR affects several signaling molecules and/or pathways, via the β3-adrenergic system, impinging on signaling molecules like PKA, PGC1α, C/EBPβ, and Dio2, which eventually affects the activity of the uncoupling protein UCP1, which produces heat (and not ATP) from fatty acids. Not mentioned in the text is the reciprocal regulatory loop consisting of the microRNA species hsa-mir-155 and the transcription factor C/EBPβ, which can be manipulated to reinforce the "beige" phenotype of the adipocyte after differentiation from the stem cells or preadipocytes.
