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Seoung-Ryoung Choi, Joel Frandsen, Prabagaran Narayanasamy
Menaquinone (MK) biosynthesis pathway is a potential target for evaluating antimicrobials in gram-positive bacteria. Here, 1,4-dihydroxy-2-naphthoate prenyltransferase (MenA) was targeted to reduce methicillin-resistant Staphylococcus aureus (MRSA) growth. MenA inhibiting, long chain-based compounds were designed, synthesized and evaluated against MRSA and menaquinone utilizing bacteria in aerobic conditions. The results showed that these bacteria were susceptible to most of the compounds. Menaquinone (MK-4) supplementation rescued MRSA growth, suggesting these compounds inhibit MK biosynthesis...
January 10, 2017: Scientific Reports
Cees Vermeer, Cynthia van 't Hoofd, Marjo H J Knapen, Sofia Xanthoulea
Vitamin K is the collective term for compounds that share a 2-methyl-1,4-naphthoquinone ring, but differ in the side-chain at the 3-position. We synthesized novel 2-methyl-1,4-naphthoquinone derivatives with different side chain length at the 3-position. Derivatives with C-14 and C-16 tails showed the highest in vitro bioactivity resulting in 2.5 and 2-fold higher carboxylated osteocalcin synthesis in MG63 cells than menaquinone-4 (MK-4, form of vitamin K2). Longer side chain lengths resulted in lower bioactivity...
January 15, 2017: Bioorganic & Medicinal Chemistry Letters
Seiko Noda, Asako Yamada, Rieko Tanabe, Kanae Nakaoka, Takayuki Hosoi, Masae Goseki-Sone
Alkaline phosphatase (ALP) hydrolyzes several monophosphate esters into inorganic acid and alcohol. In humans, 4 kinds of ALP isozymes have been identified: tissue-nonspecific ALP, intestinal ALP, placental ALP, and germ cell ALP. Intestinal ALP is expressed at a high concentration in the brush border membrane of intestinal epithelial cells and is known to be affected by several kinds of nutrients, such as lipids, but the physiological function of intestinal ALP has remained elusive. Vitamin K is an essential cofactor for the posttranslational carboxylation of glutamate residues into γ-carboxy glutamate...
November 2016: Nutrition Research
Kristin M McCabe, Sarah L Booth, Xueyan Fu, Emilie Ward, Michael A Adams, Rachel M Holden
BACKGROUND: Patients with chronic kidney disease (CKD) have very high levels of uncarboxylated, inactive, extra-hepatic vitamin K-dependent proteins measured in circulation, putting them at risk for complications of vitamin K deficiency. The major form of vitamin K found in the liver is phylloquinone (K1). Menaquinone-4 (MK-4) is the form of vitamin K that is preferentially found in extra-hepatic tissues. METHODS: In the present study, we assessed tissue concentrations of K1 and MK-4 and the expression of vitamin K-related genes in a rat model of adenine-induced CKD...
2017: American Journal of Nephrology
Hani M Khojah, Sameh Ahmed, Mahran S Abdel-Rahman, Khaled M Alkhalil, Al-Badr Hamza
The aim of this study was to evaluate the possible role of vitamin K homologs as potential biomarkers for disease activity in patients with rheumatoid arthritis (RA). In this study, 42 patients with RA and 40 healthy controls were enrolled. Serum levels of vitamin K homologs were measured using a high-performance liquid chromatography-fluorescence method. Different biochemical and clinical markers for disease activity were measured and correlated with serum levels of vitamin K homologs. There were no significant differences between RA patients and healthy subjects in demographic data...
October 8, 2016: Journal of Bone and Mineral Metabolism
David K Cundiff, Paul S Agutter
BACKGROUND: Nutrition researchers recently recognized that deficiency of vitamin K2 (menaquinone: MK-4-MK-13) is widespread and contributes to cardiovascular disease (CVD). The deficiency of vitamin K2 or vitamin K inhibition with warfarin leads to calcium deposition in the arterial blood vessels. METHODS: Using publicly available sources, we collected food commodity availability data and derived nutrient profiles including vitamin K2 for people from 168 countries...
August 24, 2016: Curēus
Yan-Xia Yu, Yi-Pei Li, Feng Gao, Qing-Song Hu, Yan Zhang, Dong Chen, Guang-Hui Wang
AIM: Increasing evidence has shown that environmental factors such as rotenone and paraquat induce neuroinflammation, which contributes to the pathogenesis of Parkinson's disease (PD). In this study, we investigated the molecular mechanisms underlying the repression by menaquinone-4 (MK-4), a subtype of vitamin K2, of rotenone-induced microglial activation in vitro. METHODS: A microglial cell line (BV2) was exposed to rotenone (1 μmol/L) with or without MK-4 treatment...
September 2016: Acta Pharmacologica Sinica
Toshio Okano
Vitamin K is a cofactor for γ-glutamyl carboxylase, which catalyzes the posttranslational conversion of specific glutamyl residues to γ-carboxyglutamyl residues in a variety of vitamin K-dependent proteins (VKDPs) involved in blood coagulation, bone and cartilage metabolism, signal transduction, and cell proliferation. Despite the great advances in the genetic, structural, and functional studies of VKDPs as well as the enzymes identified as part of the vitamin K cycle which enable it to be repeatedly recycled within the cells, little is known of the identity and roles of key regulators of vitamin K metabolism in mammals and humans...
2016: Yakugaku Zasshi: Journal of the Pharmaceutical Society of Japan
Stephanie G Harshman, Xueyan Fu, J Philip Karl, Kathryn Barger, Stefania Lamon-Fava, Athan Kuliopulos, Andrew S Greenberg, Donald Smith, Xiaohua Shen, Sarah L Booth
BACKGROUND: There has been limited characterization of biological variables that impact vitamin K metabolism. This gap in knowledge can limit the translation of data obtained from preclinical animal studies to future human studies. OBJECTIVE: The purpose of this study was to determine the effects of diet, sex, and housing on serum, tissue, and fecal vitamin K concentrations and gene expression in C57BL6 mice during dietary vitamin K manipulation. METHODS: C57BL6 4-mo-old male and female mice were randomly assigned to conventional or suspended-wire cages and fed control [1400 ± 80 μg phylloquinone (PK)/kg] or deficient (31 ± 0...
August 2016: Journal of Nutrition
Yuji Ikari, Sho Torii, Atsushi Shioi, Toshio Okano
BACKGROUND: Dietary intake of vitamin K has been reported to reduce coronary artery calcification (CAC) and cardiovascular events. However, it is unknown whether supplemental menaquinone (MK)-4 can reduce CAC or arterial stiffness. To study the effect of MK-4 supplementation on CAC and brachial ankle pulse wave velocity (baPWV). METHODS: This study is a single arm design to take 45 mg/day MK-4 daily as a therapeutic drug for 1 year. Primary endpoint was CAC score determined using 64-slice multislice CT (Siemens), and the secondary endpoint was baPWV measured before and 1 year after MK-4 therapy...
May 12, 2016: Nutrition Journal
Guylaine Ferland, Isabelle Doucet, Dominique Mainville
Whether through the vitamin K-dependent proteins or the individual K vitamers, vitamin K (VK) is associated with a number of age-related conditions (e.g., osteoporosis, atherosclerosis, insulin resistance, cognitive decline). In light of this, we investigated the influence of lifetime dietary VK exposure on the tissue distribution of phylloquinone (K₁) and menaquinone-4 (MK-4) vitamers in 3-, 12- and 22-month-old male and female rats fed different K₁ diets since weaning or subjected to a 40% calorie restricted diet (CR) since adulthood...
March 4, 2016: Nutrients
Ineke J Riphagen, Jan C van der Molen, Martijn van Faassen, Gerjan Navis, Martin H de Borst, Frits A J Muskiet, Wilhelmina H A de Jong, Stephan J L Bakker, Ido P Kema
BACKGROUND: Given the growing interest in the health benefits of vitamin K, there is great need for development of new high-throughput methods for quantitative determination of vitamin K in plasma. We describe a simple and rapid method for measurement of plasma vitamin K1 (phylloquinone [PK]) and K2 (menaquinones [MK]-4 and -7). Furthermore, we investigated the association of fasting plasma vitamin K with functional vitamin K insufficiency in renal transplant recipients (RTR). METHODS: We used HPLC-tandem mass spectrometry with atmospheric pressure chemical ionization for measurement of plasma PK, MK-4, and MK-7...
July 1, 2016: Clinical Chemistry and Laboratory Medicine: CCLM
Hironobu Katsuyama, Shigeko Fushimi, Kunikazu Yamane, Yoko Watanabe, Koichiro Shimoya, Toshiko Okuyama, Midori Katsuyama, Kiyofumi Saijoh, Masafumi Tomita
Vitamin K2 (VK2) has been used as a therapeutic agent for osteoporosis, since it has been suggested to be able to reduce the frequency of fractures by improving bone quality; however, bone turnover is strictly regulated by various cytokines and hormones. In the present study, the effect of menaquinone-4 (MK-4) on bone turnover was investigated using the senescence-accelerated mouse prone 6 (SAMP6) strain. Since water-immersion restraint stress (WRS) causes a significant decrease in bone mineral density (BMD), WRS was used as the bone resorption model in the SAMP6 strain...
September 2015: Experimental and Therapeutic Medicine
Sameh Ahmed, Ashraf M Mahmoud
Recently, new physiological roles of vitamin K homologues have been established in the treatment of rheumatoid arthritis, osteoporosis, hepatocellular carcinoma and leukemia. However, relatively high plasma protein binding, low plasma concentrations and occurrences of interfering lipids make accurate determination of vitamin K homologues a challenging task. Therefore, a sensitive and reliable salting-out assisted liquid/liquid extraction (SALLE) method coupled with HPLC-Fluorescence detection was designed for efficient extraction and quantification of trace levels of vitamin K homologues in human plasma...
November 1, 2015: Talanta
Karen M Houghton, Xochitl C Morgan, Kirill Lagutin, Andrew D MacKenzie, Mikhail Vyssotskii, Kevin A Mitchell, Ian R McDonald, Hugh W Morgan, Jean F Power, John W Moreau, Eric Hanssen, Matthew B Stott
An aerobic, thermophilic and cellulolytic bacterium, designated strain WKT50.2T, was isolated from geothermal soil at Waikite, New Zealand. Strain WKT50.2T grew at 53-76 °C and at pH 5.9-8.2. The DNA G+C content was 58.4 mol%. The major fatty acids were 12-methyl C18 : 0 and C18 : 0. Polar lipids were all linked to long-chain 1,2-diols, and comprised 2-acylalkyldiol-1-O-phosphoinositol (diolPI), 2-acylalkyldiol-1-O-phosphoacylmannoside (diolP-acylMan), 2-acylalkyldiol-1-O-phosphoinositol acylmannoside (diolPI-acylMan) and 2-acylalkyldiol-1-O-phosphoinositol mannoside (diolPI-Man)...
December 2015: International Journal of Systematic and Evolutionary Microbiology
Kai Tang, Bo Yuan, Qiliang Lai, Ruigang Wang, Haizhu Bao, Fu Ying Feng
A Gram-stain-negative, non-spore-forming, short rod-shaped, non-motile, light-pink bacterial strain, MIMtkLc17T, was isolated from biological soil crusts collected in Liangcheng, Inner Mongolia. Growth of strain MIMtkLc17T was observed at 2-35 °C and in the presence of 1% (w/v) NaCl. Phylogenetic analysis of 16S rRNA gene sequences showed that sequence similarities between strain MIMtkLc17T and the type strains of species of the genus Hymenobacter ranged from 89.93% to 96.49%. Strain MIMtkLc17T can secrete mass polysaccharide...
December 2015: International Journal of Systematic and Evolutionary Microbiology
Osama Sammra, Anna Balbutskaya, Hivda Ülbegi-Mohyla, Samy Nagib, Christoph Lämmler, Peter Kämpfer, Stefanie P Glaeser, Jan Golke, Hans-Jürgen Busse, Ellen Prenger-Berninghoff, Ursula Siebert, Amir Abdulmawjood, Günter Klein
A polyphasic taxonomic study was performed on an unidentified Arcanobacterium-like, Gram-stain-positive bacterium, strain 2710T, isolated from a harbour seal. Comparative 16S rRNA gene sequence analysis showed that this bacterial strain belonged to the genus Arcanobacterium and was related most closely to the type strains of Arcanobacterium phocae (98.4 % similarity) and Arcanobacterium phocisimile (97.5 %). 16S rRNA gene sequence similarities to the type strains of other Arcanobacterium species were between 95...
December 2015: International Journal of Systematic and Evolutionary Microbiology
Jing Yu, Cui-Ping Ding, Jing Wang, Ting Wang, Tao Zhang, Xiao-Yan Zeng, Jun-Yang Wang
Previous studies have demonstrated that glutamate plays an important role in the development of pathological pain. This study investigates the expression changes of glutamate and the roles of different types of glutamate receptors in the red nucleus (RN) in the development of neuropathic allodynia induced by spared nerve injury (SNI). Immunohistochemistry indicated that glutamate was constitutively expressed in the RN of normal rats. After SNI, the expression levels of glutamate were significantly increased in the RN at 1 week and reached the highest level at 2 weeks postinjury compared with sham-operated and normal rats...
December 2015: Journal of Neuroscience Research
Su-Jin Kim, Jae-Chan Lee, Song-Ih Han, Kyung-Sook Whang
A Gram-staining-positive, moderately halophilic bacterium, designated strain NGS-2T, was isolated from sediment of a solar saltern pond located in Shinan, Korea. Strain NGS-2T was a strictly aerobic, non-motile rod that grew at pH 5.0-10.0 (optimum, pH 8.0), at 10-30 °C (optimum, 28 °C) and in the presence of 1-20 % (w/v) NaCl (optimum, 10 % NaCl). Phylogenetic analyses based on 16S rRNA gene sequences indicated that strain NGS-2T belonged to the genus Halobacillus, with sequence similarity of 98...
December 2015: International Journal of Systematic and Evolutionary Microbiology
Zhao Jiang, Wei-Hua Zhang, Chang-Guo Yuan, Jia-Yang Chen, Li-Xiang Cao, Dong-Jin Park, Min Xiao, Chang-Jin Kim, Wen-Jun Li
A novel Gram-staining positive, catalase-positive, oxidase-negative, aerobic, non-motile coccus, designated strain YIM 13062(T), was isolated from a marine sediment sample collected from the Indian Ocean. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain YIM 13062(T) belongs to the genus Kocuria, and is closely related to Kocuria polaris NBRC 103063(T) (97.8 % similarity), Kocuria rosea NBRC 3768(T) (97.6 % similarity) and Kocuria carniphila JCM 14118(T) (97.4 % similarity). The strain grew optimally at 28 °C, pH 8...
December 2015: Antonie Van Leeuwenhoek
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