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Micronutrients
Published in Chuong Pham-Huy, Bruno Pham Huy, Food and Lifestyle in Health and Disease, 2022
Chuong Pham-Huy, Bruno Pham Huy
Vitamin K is a group of fat-soluble vitamins with a common chemical structure of 2-methyl-1, 4-naphthoquinone, and includes two natural vitamers: vitamin K1 or phylloquinone and vitamin K2 or menaquinones (3, 9, 33, 82–88). In addition, menadiol and menadione, called vitamin K3, are synthetic compounds that can be metabolized to phylloquinone in the body (33, 85). However, they are reported to have adverse effects such as hemolysis and liver toxicity and are not used in therapy (82, 85). Therefore, only vitamin K1 and vitamin K2 are called vitamin K and naturally exist in some foods and are available as dietary supplement.
Components of Nutrition
Published in Christopher Cumo, Ancestral Diets and Nutrition, 2020
Vitamin K activates the protein cascade necessary to clot blood in a wound and strengthens bones by binding calcium to proteins in them. Vitamin K is a broad designation for the compounds phylloquinone (K1), menaquinone (K2), and menadione (K3), which share properties and tend to occur in leaves. Good options are dark green leafy vegetables, broccoli, cauliflower, soybeans and their products, green tea, and wheat bran. Animal sources include liver and fermented dairy products. Laboratories synthesize menadione, whose potential harm diminishes its suitability in nutritional supplements. Vitamin K’s RDA is 90 micrograms for women and 120 for men.84 Diets are seldom deficient.
Fat-Soluble Vitamins
Published in Luke R. Bucci, Nutrition Applied to Injury Rehabilitation and Sports Medicine, 2020
Like other fat-soluble vitamins, vitamin K exists as a series of compounds with the same biological activity.562–566 Vitamin K is the generic term for menadione, menaquinone, and phylloquinone. As 1,4-naphthoquinone ring compounds, vitamin K vitamers are lipophilic (fat-soluble) and subject to oxidation-reduction (redox) reactions in tissues. The chief role of vitamin K is as a cofactor for enzymes that convert protein-bound glutamyl residues to γ-carboxyglutamyl residues.562–566 Prothrombin activity is dependent upon gamma carboxylation of glutamyl residues, and, thus, vitamin K is associated with antihemorrhagic and blood clotting properties. Recently, vitamin K-dependent gamma carboxylation of bone-associated proteins (osteocalcin and others) has been confirmed, and another role of vitamin K has been added: regulation of bone mineral formation.562–566 All gamma carboxylated proteins bind calcium ions in a specific manner that allows for specific functions for each protein.
Do 50/60 Hz magnetic fields influence oxidative or DNA damage responses in human SH-SY5Y neuroblastoma cells?
Published in International Journal of Radiation Biology, 2022
Ehab Mustafa, Leonardo Makinistian, Jukka Luukkonen, Jukka Juutilainen, Jonne Naarala
Clear responses to menadione were observed (Figure 2, Supplementary Table 3). Four of the oxidative stress-related genes studied showed either a statistically significant up-regulation (DUSP1, HSPA1A, SQSTM1) or down-regulation (FHL2) to menadione in all exposure conditions (with or without MFs). Most of the genes that were statistically significantly up- or down-regulated in only some of the conditions showed small fold changes (<2.0), so the differences in statistical significance are most likely due to chance (false positive or false negative findings in some of the conditions). A suggestive modification of the menadione effect by MF exposure was seen in two cases. The expression of ALOX12 was increased in both sham exposures (fold changes with SEM: 2.09 ± 0.16 and 3.98 ± 0.71), but not significantly in the MF-exposed groups. HMOX1 was upregulated after sham exposures (2.95 ± 0.28 and 3.606 ± 0.430) and in the cells exposed to 60 Hz MFs (3.849 ± 0.854), but not significantly in the 50 Hz MF group. However, examination of the data revealed that the fold changes were of similar direction and magnitude in all treatment groups, so the lack of significance in the MF groups was apparently due to chance.
Protocatechuic acid protects against menadione-induced liver damage by up-regulating nuclear erythroid-related factor 2
Published in Drug and Chemical Toxicology, 2020
Menadione (Vitamin K3), a redox cycling polycyclic aromatic ketone, is an over-the-counter (OTC) drug used in the treatment of abdominal cramps, colitis, cancer, diarrhea, hay fever, hemorrahage, hypoprothrombinemia, osteoporosis, and joint pains (Ferland 2012, Graciani and Ximenes 2012). Despite the positive treatment outcomes following menadione administration, toxicity resulting from the abuse has reduced its application and availability. These side effects are not limited to hemolytic anemia and, neonatal brain and liver damages (Ferland 2012). Interestingly, it was banned in US because of its abuse and the associated side effects. Furthermore, generation of reactive oxygen species (ROS) is central to menadione-induced cellular damage (Loor et al.2010).
ROS-Activated homodimeric podophyllotoxin nanomedicine with self-accelerating drug release for efficient cancer eradication
Published in Drug Delivery, 2021
Reports show that vitamin K3 (VK3), also called menadione, has superior tumor-activating ROS production ability (Yang et al., 2018). NAD(p)H: quinone oxidoreductase-1 (NQO1) enzyme catalyzes VK3 reduction to semiquinone and hydroquinone, whose oxidation to quinone generates ROS ( Dasari et al., 2017; Xu et al., 2020). Thus, the cyclic conversion among VK3, semiquinone, and hydroquinone present an effective strategy to increase ROS concentration in cells (Yang et al., 2018). Moreover, the expression of NQO1 is 100-folds more in cancer cells than in normal cells (Ma et al., 2015). These data show that VK3 is a promising tumor-specifical ROS generator.