Vitamin K2

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Information on nutritional supplements people with ALS have been taking


Effects on ALS[edit]

Human UBIAD1 localizes to mitochondria and converts vitamin K1 to vitamin K2. Vitamin K2 is best known as a cofactor in blood coagulation, but in bacteria it is a membrane-bound electron carrier. Whether vitamin K2 exerts a similar carrier function in eukaryotic cells is unknown. We identified Drosophila UBIAD1/Heix as a modifier of pink1, a gene mutated in Parkinson’s disease that affects mitochondrial function. We found that vitamin K2 was necessary and sufficient to transfer electrons in Drosophila mitochondria. Heix mutants showed severe mitochondrial defects that were rescued by vitamin K2, and, similar to ubiquinone, vitamin K2 transferred electrons in Drosophila mitochondria, resulting in more efficient adenosine triphosphate (ATP) production. Thus, mitochondrial dysfunction was rescued by vitamin K2 that serves as a mitochondrial electron carrier, helping to maintain normal ATP production.[1][2]

Vitamin K2 is a possible treatment for mitochondrial pathologies such as Parkinson's disease and amyotrophic lateral sclerosis.

K2 may protect from Vitamin D3 toxicity if high amounts of D3 is supplemented.[3]

Vitamin K2 may induce mitochondria-mediated apoptosis: Here, we identified Bcl-2 antagonist killer 1 (Bak) as a molecular target of VK2-induced apoptosis. VK2 directly interacts with Bak and induces mitochondrial-mediated apoptosis. Although Bak and Bcl-2-associated X protein (Bax), another member of the Bcl-2 family, are generally thought to be functionally redundant, only Bak is necessary and sufficient for VK2-induced cytochrome c (cyt c) release and cell death. Moreover, VK2-2,3 epoxide, an intracellular metabolite of VK2, was shown to covalently bind to the cysteine-166 residue of Bak. Several lines of evidence suggested that the covalent attachment of VK2 is critical for apoptosis induction. Thus this study reveals a specific role for Bak in mitochondria-mediated apoptosis. This study also provides insight into the anticancer effects of VK2 and suggests that Bak may be a potential target of cancer therapy. [4]


Forms[edit]

Only few foods have significant amount of K2. There are several menaquinone forms of Vitamin K2, in supplements common are MK-4 and MK-7. Which menaquinones have effect on ALS is unclear (add info here if found). MK-7 has longer activity of those two, and utilization from tablets is about 78 %. MK-4 has effect from 1.5 mg upwards. MK-4 is short lived and to maximize effect should be used 3 times a day.

Cautions[edit]

Unsafe with at least following medical conditions: diabetes, kidney disease, liver disease. Do not take if using warfarin (Coumadin), might decrease warfarin effectiveness. (Source: WebMD)

Discussion threads on the ALSTDI forum[edit]

Immune modulation in ALS - harmful or beneficial?


Regulated pathways[edit]

Where to get it[edit]

Humans can partly convert K1 to K2, amount of K1 in a typical diet is 10 times that of vitamin K2. Conversion process is inefficient. K2 is also produced in the large intestine by gut bacteria. Broad-spectrum antibiotics may contribute to K2 deficiency. Animal sources include high-fat dairy products from grass-fed cows, liver, other organs, egg yolks. Animal foods contain MK-4, fermented foods like sauerkraut, natto and miso contain more of the longer subtypes, MK-5 to MK-14.

  • Amazon.co.uk - Life Extension Super K with Advanced K2 Complex x90 Softgels
  • iHerb.com - Life Extension Super K with Advanced K2 Complex x90 Softgels

References[edit]

Vitamin K2 Takes Charge

Science 8 June 2012: Vol. 336 no. 6086 pp. 1241-1242 DOI: 10.1126/science.1223812

Sheetal Bhalarao, Thomas R. Clandinin

Mitochondria are dynamic organelles that play central roles in eukaryotic cellular energy metabolism. They harbor an electron transport chain (ETC) that couples electron transfer to the movement of protons across the mitochondrial inner membrane, forming an electrochemical gradient that captures chemical energy in the form of adenosine triphosphate (ATP). The biochemical and biophysical properties of the ETC have been studied in detail (1). On page 1306 of this issue, Vos et al. (2) report a new constituent of this chain. The authors show that vitamin K2 is an electron carrier, suggesting this small organic molecule as a possible treatment for mitochondrial pathologies such as Parkinson's disease and amyotrophic lateral sclerosis.


Vitamin K2 Is a Mitochondrial Electron Carrier That Rescues Pink1 Deficiency

Published Online May 10 2012 Science 8 June 2012: Vol. 336 no. 6086 pp. 1306-1310 DOI: 10.1126/science.1218632

Melissa Vos, Giovanni Esposito, Janaka N. Edirisinghe, Sven Vilain, Dominik M. Haddad, Jan R. Slabbaert, Stefanie Van Meensel, Onno Schaap, Bart De Strooper, R. Meganathan, Vanessa A. Morais, Patrik Verstreken

Human UBIAD1 localizes to mitochondria and converts vitamin K1 to vitamin K2. Vitamin K2 is best known as a cofactor in blood coagulation, but in bacteria it is a membrane-bound electron carrier. Whether vitamin K2 exerts a similar carrier function in eukaryotic cells is unknown. We identified Drosophila UBIAD1/Heix as a modifier of pink1, a gene mutated in Parkinson’s disease that affects mitochondrial function. We found that vitamin K2 was necessary and sufficient to transfer electrons in Drosophila mitochondria. Heix mutants showed severe mitochondrial defects that were rescued by vitamin K2, and, similar to ubiquinone, vitamin K2 transferred electrons in Drosophila mitochondria, resulting in more efficient adenosine triphosphate (ATP) production. Thus, mitochondrial dysfunction was rescued by vitamin K2 that serves as a mitochondrial electron carrier, helping to maintain normal ATP production.


New Potential Pathway for Treating ALS and Parkinson’s Diseases

Neuroscience News August 12, 2015 Mutations in PINK1 and its partner molecule Parkin cause hereditary forms of Parkinson’s disease. Moreover, the inability to remove defective mitochondria from nerve cells has been linked to numerous neurodegenerative diseases, including the more common forms of Parkinson’s disease and amyotrophic lateral sclerosis (ALS).


Altered expression of DJ-1 and PINK1 in sporadic ALS and in the SOD1(G93A) ALS mouse model.

Mitochondrial dysfunction is an important mechanism in the pathogenesis of neurodegenerative diseases such as Parkinson disease and amyotrophic lateral sclerosis (ALS). DJ-1 and PTEN-induced putative kinase 1 (PINK1) are important proteins for the maintenance of mitochondrial function and protection against cell death. Mutations in the genes coding for these proteins cause familial forms of Parkinson disease. Recent studies have postulated that changes in the expression of both proteins are also involved in pathologic mechanisms in ALS mouse models. Here, we studied the mRNA and protein expression of PINK1 and DJ-1 in postmortem brain and spinal cord tissue and muscle biopsy samples from ALS patients and controls and in brain, spinal cord, and gastrocnemius muscle of SOD1(G93A) ALS mice at different disease stages. We found significant decreases of PINK1 and DJ-1 mRNA levels in muscle tissue of SOD1(G93A) mice. Together with the significant decrease of PINK1 mRNA levels in human ALS muscle tissue, statistically nonsignificant reduction of DJ-1 mRNA levels, and reduced immunostaining for PINK1 in human ALS muscle, the results suggest potential pathophysiologic roles for these proteins in both mutant SOD1 transgenic mice and in sporadic ALS(G93A).
  1. Lovern & Marbois: Does menaquinone participate in brain astrocyte electron transport?. Med. Hypotheses 2013;81:587-91. PMID: 23910074. DOI. UNLABELLED: Quinone compounds act as membrane resident carriers of electrons between components of the electron transport chain in the periplasmic space of prokaryotes and in the mitochondria of eukaryotes. Vitamin K is a quinone compound in the human body in a storage form as menaquinone (MK); distribution includes regulated amounts in mitochondrial membranes. The human brain, which has low amounts of typical vitamin K dependent function (e.g., gamma carboxylase) has relatively high levels of MK, and different regions of brain have different amounts. Coenzyme Q (Q), is a quinone synthesized de novo, and the levels of synthesis decline with age. The levels of MK are dependent on dietary intake and generally increase with age. MK has a characterized role in the transfer of electrons to fumarate in prokaryotes. A newly recognized fumarate cycle has been identified in brain astrocytes. The MK precursor menadione has been shown to donate electrons directly to mitochondrial complex III. HYPOTHESIS: Vitamin K compounds function in the electron transport chain of human brain astrocytes.
  2. Wang & Hekimi: Mitochondrial respiration without ubiquinone biosynthesis. Hum. Mol. Genet. 2013;22:4768-83. PMID: 23847050. DOI. Ubiquinone (UQ), a.k.a. coenzyme Q, is a redox-active lipid that participates in several cellular processes, in particular mitochondrial electron transport. Primary UQ deficiency is a rare but severely debilitating condition. Mclk1 (a.k.a. Coq7) encodes a conserved mitochondrial enzyme that is necessary for UQ biosynthesis. We engineered conditional Mclk1 knockout models to study pathogenic effects of UQ deficiency and to assess potential therapeutic agents for the treatment of UQ deficiencies. We found that Mclk1 knockout cells are viable in the total absence of UQ. The UQ biosynthetic precursor DMQ9 accumulates in these cells and can sustain mitochondrial respiration, albeit inefficiently. We demonstrated that efficient rescue of the respiratory deficiency in UQ-deficient cells by UQ analogues is side chain length dependent, and that classical UQ analogues with alkyl side chains such as idebenone and decylUQ are inefficient in comparison with analogues with isoprenoid side chains. Furthermore, Vitamin K2, which has an isoprenoid side chain, and has been proposed to be a mitochondrial electron carrier, had no efficacy on UQ-deficient mouse cells. In our model with liver-specific loss of Mclk1, a large depletion of UQ in hepatocytes caused only a mild impairment of respiratory chain function and no gross abnormalities. In conjunction with previous findings, this surprisingly small effect of UQ depletion indicates a nonlinear dependence of mitochondrial respiratory capacity on UQ content. With this model, we also showed that diet-derived UQ10 is able to functionally rescue the electron transport deficit due to severe endogenous UQ deficiency in the liver, an organ capable of absorbing exogenous UQ.
  3. Masterjohn &: Vitamin D toxicity redefined: vitamin K and the molecular mechanism. Med. Hypotheses 2007;68:1026-34. PMID: 17145139. DOI. The dose of vitamin D that some researchers recommend as optimally therapeutic exceeds that officially recognized as safe by a factor of two; it is therefore important to determine the precise mechanism by which excessive doses of vitamin D exert toxicity so that physicians and other health care practitioners may understand how to use optimally therapeutic doses of this vitamin without the risk of adverse effects. Although the toxicity of vitamin D has conventionally been attributed to its induction of hypercalcemia, animal studies show that the toxic endpoints observed in response to hypervitaminosis D such as anorexia, lethargy, growth retardation, bone resorption, soft tissue calcification, and death can be dissociated from the hypercalcemia that usually accompanies them, demanding that an alternative explanation for the mechanism of vitamin D toxicity be developed. The hypothesis presented in this paper proposes the novel understanding that vitamin D exerts toxicity by inducing a deficiency of vitamin K. According to this model, vitamin D increases the expression of proteins whose activation depends on vitamin K-mediated carboxylation; as the demand for carboxylation increases, the pool of vitamin K is depleted. Since vitamin K is essential to the nervous system and plays important roles in protecting against bone loss and calcification of the peripheral soft tissues, its deficiency results in the symptoms associated with hypervitaminosis D. This hypothesis is circumstantially supported by the observation that animals deficient in vitamin K or vitamin K-dependent proteins exhibit remarkable similarities to animals fed toxic doses of vitamin D, and the observation that vitamin D and the vitamin K-inhibitor Warfarin have similar toxicity profiles and exert toxicity synergistically when combined. The hypothesis further proposes that vitamin A protects against the toxicity of vitamin D by decreasing the expression of vitamin K-dependent proteins and thereby exerting a vitamin K-sparing effect. If animal experiments can confirm this hypothesis, the models by which the maximum safe dose is determined would need to be revised. Physicians and other health care practitioners would be able to treat patients with doses of vitamin D that possess greater therapeutic value than those currently being used while avoiding the risk of adverse effects by administering vitamin D together with vitamins A and K.
  4. Karasawa et al.: Vitamin K2 covalently binds to Bak and induces Bak-mediated apoptosis. Mol. Pharmacol. 2013;83:613-20. PMID: 23229512. DOI. Vitamin K2 (VK2, menaquinone) is known to have anticancer activity in vitro and in vivo. Although its effect is thought to be mediated, at least in part, by the induction of apoptosis, the underlying molecular mechanism remains elusive. Here, we identified Bcl-2 antagonist killer 1 (Bak) as a molecular target of VK2-induced apoptosis. VK2 directly interacts with Bak and induces mitochondrial-mediated apoptosis. Although Bak and Bcl-2-associated X protein (Bax), another member of the Bcl-2 family, are generally thought to be functionally redundant, only Bak is necessary and sufficient for VK2-induced cytochrome c (cyt c) release and cell death. Moreover, VK2-2,3 epoxide, an intracellular metabolite of VK2, was shown to covalently bind to the cysteine-166 residue of Bak. Several lines of evidence suggested that the covalent attachment of VK2 is critical for apoptosis induction. Thus this study reveals a specific role for Bak in mitochondria-mediated apoptosis. This study also provides insight into the anticancer effects of VK2 and suggests that Bak may be a potential target of cancer therapy.