The NAD+/PARP1/SIRT1 Axis in Aging.

Science.gov (United States)

Mendelsohn, Andrew R; Larrick, James W

2017-06-01

NAD+ levels decline with age in diverse animals from Caenorhabditis elegans to mice. Raising NAD+ levels by dietary supplementation with NAD+ precursors, nicotinamide riboside (NR) or nicotinamide mononucleotide (NMN), improves mitochondrial function and muscle and neural and melanocyte stem cell function in mice, as well as increases murine life span. Decreased NAD+ levels with age reduce SIRT1 function and reduce the mitochondrial unfolded protein response, which can be overcome by NR supplementation. Decreased NAD+ levels cause NAD+-binding protein DBC1 to form a complex with PARP1, inhibiting poly(adenosine diphosphate-ribose) polymerase (PARP) catalytic activity. Old mice have increased amounts of DBC1-PARP1 complexes, lower PARP activity, increased DNA damage, and reduced nonhomologous end joining and homologous recombination repair. DBC1-PARP1 complexes in old mice can be broken by increasing NAD+ levels through treatment with NMN, reducing DNA damage and restoring PARP activity to youthful levels. The mechanism of declining NAD+ levels and its fundamental importance to aging are yet to be elucidated. There is a correlation of PARP activity with mammalian life span that suggests that NAD+/SIRT1/PARP1 may be more significant than the modest effects on life span observed for NR supplementation in old mice. The NAD+/PARP1/SIRT1 axis may link NAD+ levels and DNA damage with the apparent epigenomic DNA methylation clocks that have been described.

Oleate ameliorates palmitate-induced reduction of NAMPT activity and NAD levels in primary human hepatocytes and hepatocarcinoma cells.

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Penke, Melanie; Schuster, Susanne; Gorski, Theresa; Gebhardt, Rolf; Kiess, Wieland; Garten, Antje

2017-10-03

Nicotinamide phosphoribosyltransferase (NAMPT) and nicotinamide adenine dinucleotide (NAD) levels are crucial for liver function. The saturated fatty acid palmitate and the unsaturated fatty acid oleate are the main free fatty acids in adipose tissue and human diet. We asked how these fatty acids affect cell survival, NAMPT and NAD levels in HepG2 cells and primary human hepatocytes. HepG2 cells were stimulated with palmitate (0.5mM), oleate (1mM) or a combination of both (0.5mM/1mM) as well as nicotinamide mononucleotide (NMN) (0.5 mM) or the specific NAMPT inhibitor FK866 (10nM). Cell survival was measured by WST-1 assay and Annexin V/propidium iodide staining. NAD levels were determined by NAD/NADH Assay or HPLC. Protein and mRNA levels were analysed by Western blot analyses and qPCR, respectively. NAMPT enzyme activity was measured using radiolabelled 14 C-nicotinamide. Lipids were stained by Oil red O staining. Palmitate significantly reduced cell survival and induced apoptosis at physiological doses. NAMPT activity and NAD levels significantly declined after 48h of palmitate. In addition, NAMPT mRNA expression was enhanced which was associated with increased NAMPT release into the supernatant, while intracellular NAMPT protein levels remained stable. Oleate alone did not influence cell viability and NAMPT activity but ameliorated the negative impact of palmitate on cell survival, NAMPT activity and NAD levels, as well as the increased NAMPT mRNA expression and secretion. NMN was able to normalize intracellular NAD levels but did not ameliorate cell viability after co-stimulation with palmitate. FK866, a specific NAMPT inhibitor did not influence lipid accumulation after oleate-treatment. Palmitate targets NAMPT activity with a consequent cellular depletion of NAD. Oleate protects from palmitate-induced apoptosis and variation of NAMPT and NAD levels. Palmitate-induced cell stress leads to an increase of NAMPT mRNA and accumulation in the supernatant. However

Regulation of Nampt expression by transcriptional coactivator NCOA6 in pancreatic β-cells

International Nuclear Information System (INIS)

Yoon, Jin; Lee, Kyung Jin; Oh, Gyun-Sik; Kim, Geun Hyang; Kim, Seung-Whan

2017-01-01

Nuclear receptor coactivator 6 (NCOA6) is a transcriptional coactivator and crucial for insulin secretion and glucose metabolism in pancreatic β-cells. However, the regulatory mechanism of β-cell function by NCOA6 is largely unknown. In this study, we found that the transcript levels of nicotinamide phosphoribosyltransferase (Nampt) were decreased in islets of NCOA6 +/− mice compared with NCOA6 +/+ mice. Moreover, NCOA6 overexpression increased the levels of Nampt transcripts in the mouse pancreatic β-cell line NIT-1. Promoter analyses showed that transcriptional activity of the Nampt promoter was stimulated by cooperation of sterol regulatory element binding protein-1c (SREBP-1c) and NCOA6. Additional studies using mutant promoters demonstrated that SREBP-1c activates Nampt promoter through the sterol regulatory element (SRE), but not through the E-box. Using chromatin immunoprecipitation assay, NCOA6 was also shown to be directly recruited to the SRE region of the Nampt promoter. Furthermore, treatment with nicotinamide mononucleotide (NMN), a product of the Nampt reaction and a key NAD + intermediate, ameliorates glucose-stimulated insulin secretion from NCOA6 +/− islets. These results suggest that NCOA6 stimulates insulin secretion, at least partially, by modulating Nampt expression in pancreatic β-cells. - Highlights: • Nampt transcription in β-cells is activated by SREBP-1c through the SRE element. • NCOA6 enhances the transcriptional activity of SREBP-1c in the Nampt promoter. • Defective insulin secretion of NCOA6 +/− islets is recovered by NMN treatment. • NCOA6 is reportedly the first coactivator involved in Nampt expression.

Increasing NAD Synthesis in Muscle via Nicotinamide Phosphoribosyltransferase Is Not Sufficient to Promote Oxidative Metabolism*

Science.gov (United States)

Frederick, David W.; Davis, James G.; Dávila, Antonio; Agarwal, Beamon; Michan, Shaday; Puchowicz, Michelle A.; Nakamaru-Ogiso, Eiko; Baur, Joseph A.

2015-01-01

The NAD biosynthetic precursors nicotinamide mononucleotide and nicotinamide riboside are reported to confer resistance to metabolic defects induced by high fat feeding in part by promoting oxidative metabolism in skeletal muscle. Similar effects are obtained by germ line deletion of major NAD-consuming enzymes, suggesting that the bioavailability of NAD is limiting for maximal oxidative capacity. However, because of their systemic nature, the degree to which these interventions exert cell- or tissue-autonomous effects is unclear. Here, we report a tissue-specific approach to increase NAD biosynthesis only in muscle by overexpressing nicotinamide phosphoribosyltransferase, the rate-limiting enzyme in the salvage pathway that converts nicotinamide to NAD (mNAMPT mice). These mice display a ∼50% increase in skeletal muscle NAD levels, comparable with the effects of dietary NAD precursors, exercise regimens, or loss of poly(ADP-ribose) polymerases yet surprisingly do not exhibit changes in muscle mitochondrial biogenesis or mitochondrial function and are equally susceptible to the metabolic consequences of high fat feeding. We further report that chronic elevation of muscle NAD in vivo does not perturb the NAD/NADH redox ratio. These studies reveal for the first time the metabolic effects of tissue-specific increases in NAD synthesis and suggest that critical sites of action for supplemental NAD precursors reside outside of the heart and skeletal muscle. PMID:25411251

1H NMR analysis of complexation of hydrotropic agents nicotinamide and caffeine with aromatic biologically active molecules in aqueous solution

Science.gov (United States)

Lantushenko, Anastasia O.; Mukhina, Yulia V.; Veselkov, Kyrill A.; Davies, David B.; Veselkov, Alexei N.

2004-07-01

NMR spectroscopy has been used to elucidate the molecular mechanism of solubilization action of hydrotropic agents nicotinamide (NA) and caffeine (CAF). Hetero-association of NA with riboflavine-mononucleotide (FMN) and CAF with low soluble in aqueous solution synthetic analogue of antibiotic actinomycin D, actinocyl-bis-(3-dimethylaminopropyl) amine (Actill), has been investigated by 500 MHz 1H NMR spectroscopy. Concentration and temperature dependences of proton chemical shifts have been analysed in terms of a statistical-thermodynamic model of indefinite self- and heteroassociation of aromatic molecules. The obtained results enable to conclude that NA-FMN and CAF-Actill intermolecular complexes are mainly stabilized by the stacking interactions of the aromatic chromophores. Hetero-association of the investigated molecules plays an important role in solubilization of aromatic drugs by hydrotropic agents nicotinamide and caffeine.

PeakSeeker: a program for interpreting genotypes of mononucleotide repeats

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Salipante Stephen J

2009-02-01

Full Text Available Abstract Background Mononucleotide repeat microsatellites are abundant, highly polymorphic DNA sequences, having the potential to serve as valuable genetic markers. Use of mononucleotide microsatellites has been limited by their tendency to produce "stutter", confounding signals from insertions and deletions within the mononucleotide tract that occur during PCR, which complicates interpretation of genotypes by masking the true position of alleles. Consequently, microsatellites with larger repeating subunits (dinucleotide and trinucleotide motifs are used, which produce less stutter but are less genetically heterogeneous and less informative. A method to interpret the genotypes of mononucleotide repeats would permit the widespread use of those highly informative microsatellites in genetic research. Findings We have developed an approach to interpret genotypes of mononucleotide repeats using a software program, named PeakSeeker. PeakSeeker interprets experimental electropherograms as the most likely product of signals from individual alleles. Because mononucleotide tracts demonstrate locus-specific patterns of stutter peaks, this approach requires that the genotype pattern from a single allele is defined for each marker, which can be approximated by genotyping single DNA molecules or homozygotes. We have evaluated the program's ability to discriminate various types of homozygous and heterozygous mononucleotide loci using simulated and experimental data. Conclusion Mononucleotide tracts offer significant advantages over di- and tri-nucleotide microsatellite markers traditionally employed in genetic research. The PeakSeeker algorithm provides a high-throughput means to type mononucleotide tracts using conventional and widely implemented fragment length polymorphism genotyping. Furthermore, the PeakSeeker algorithm could potentially be adapted to improve, and perhaps to standardize, the analysis of conventional microsatellite genotypes.

Endogenous Nampt upregulation is associated with diabetic nephropathy inflammatory-fibrosis through the NF-κB p65 and Sirt1 pathway; NMN alleviates diabetic nephropathy inflammatory-fibrosis by inhibiting endogenous Nampt.

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Chen, Ye; Liang, Yuzhen; Hu, Tingting; Wei, Riming; Cai, Congjie; Wang, Ping; Wang, Lingyu; Qiao, Wei; Feng, Leping

2017-11-01

Nicotinamide phosphoribosyltransferase (Nampt) is a key enzyme in the nicotinamide adenine dinucleotide (NAD + ) biosynthetic pathway. Exogenous extra cellular Nampt has been reported to increase the synthesis of pro-fibrotic molecules in various types of renal cells. However, the role of endogenous Namptenzymatic activity in diabetic renal cells, particularly those associated with inflammation and fibrosis through the nuclear factor (NF)-κB p65 and sirtuin 1 (Sirt1) pathway is still unknown. In the present study, a possible mechanism by which endogenous Nampt upregulation affects the expression of pro-inflammatory and pro-fibrotic cytokines in vivo and in vitro , is reported. The present results demonstrate that the expression of vimentin and fibronectin was directly implicated in endogenous Nampt upregulation. The expression levels of Poly(ADP-ribose) polymerase-1, NF-κB p65, forkhead box protein O1 and B-cell lymphoma 2-like protein 4 were also significantly increased at 96 h compared with control group (Pendogenous Nampt upregulation. Furthermore, the expression level of Sirt1 was significantly reduced (Pendogenous Nampt upregulation may be critical in the treatment of DN pro-inflammatory fibrosis and NMN is likely to be a potential pharmacological agent for the treatment of resistant DN nephritic fibrosis.

Yeast Interacting Proteins Database: YGR010W, YLR328W [Yeast Interacting Proteins Database

Lifescience Database Archive (English)

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Yeast Interacting Proteins Database: YNL189W, YLR328W [Yeast Interacting Proteins Database

Lifescience Database Archive (English)

Full Text Available ait as prey (0) YLR328W NMA1 Nicotinic acid mononucleotide adenylyltransferase, involved in pathways... of NAD biosynthesis, including the de novo, NAD(+) salvage, and nicotinamide riboside salvage pathways... Nicotinic acid mononucleotide adenylyltransferase, involved in pathways of NAD biosynthesis, including the ...de novo, NAD(+) salvage, and nicotinamide riboside salvage pathways Rows with this prey as prey Rows with th

Yeast Interacting Proteins Database: YML064C, YLR328W [Yeast Interacting Proteins Database

Lifescience Database Archive (English)

Full Text Available th this bait as prey (0) YLR328W NMA1 Nicotinic acid mononucleotide adenylyltransferase, involved in pathways... of NAD biosynthesis, including the de novo, NAD(+) salvage, and nicotinamide riboside salvage pathways...ic acid mononucleotide adenylyltransferase, involved in pathways of NAD biosynthe...sis, including the de novo, NAD(+) salvage, and nicotinamide riboside salvage pathways Rows with this prey a

Yeast Interacting Proteins Database: YLR328W, YLR328W [Yeast Interacting Proteins Database

Lifescience Database Archive (English)

Full Text Available YLR328W NMA1 Nicotinic acid mononucleotide adenylyltransferase, involved in pathways... of NAD biosynthesis, including the de novo, NAD(+) salvage, and nicotinamide riboside salvage pathways Row...ylyltransferase, involved in pathways of NAD biosynthesis, including the de novo,... NAD(+) salvage, and nicotinamide riboside salvage pathways Rows with this prey as prey (4) Rows with this p... description Nicotinic acid mononucleotide adenylyltransferase, involved in pathways

FK866-induced NAMPT inhibition activates AMPK and downregulates mTOR signaling in hepatocarcinoma cells

Energy Technology Data Exchange (ETDEWEB)

Schuster, Susanne, E-mail: Susanne.Schuster@medizin.uni-leipzig.de [Center for Pediatric Research Leipzig, University Hospital for Children and Adolescents, Faculty of Medicine, University of Leipzig, Liebigstr. 21, 04103 Leipzig (Germany); Penke, Melanie; Gorski, Theresa [Center for Pediatric Research Leipzig, University Hospital for Children and Adolescents, Faculty of Medicine, University of Leipzig, Liebigstr. 21, 04103 Leipzig (Germany); Gebhardt, Rolf [Institute of Biochemistry, Faculty of Medicine, University of Leipzig, Johannisallee 30, 04103 Leipzig (Germany); Weiss, Thomas S. [Children' s University Hospital, University of Regensburg, Franz-Josef-Strauss-Allee 11, 93053 Regensburg (Germany); Kiess, Wieland; Garten, Antje [Center for Pediatric Research Leipzig, University Hospital for Children and Adolescents, Faculty of Medicine, University of Leipzig, Liebigstr. 21, 04103 Leipzig (Germany)

2015-03-06

Background: Nicotinamide phosphoribosyltransferase (NAMPT) is the key enzyme of the NAD salvage pathway starting from nicotinamide. Cancer cells have an increased demand for NAD due to their high proliferation and DNA repair rate. Consequently, NAMPT is considered as a putative target for anti-cancer therapies. There is evidence that AMP-activated protein kinase (AMPK) and mammalian target of rapamycin (mTOR) become dysregulated during the development of hepatocellular carcinoma (HCC). Here, we investigated the effects of NAMPT inhibition by its specific inhibitor FK866 on the viability of hepatocarcinoma cells and analyzed the effects of FK866 on the nutrient sensor AMPK and mTOR complex1 (mTORC1) signaling. Results: FK866 markedly decreased NAMPT activity and NAD content in hepatocarcinoma cells (Huh7 cells, Hep3B cells) and led to delayed ATP reduction which was associated with increased cell death. These effects could be abrogated by administration of nicotinamide mononucleotide (NMN), the enzyme product of NAMPT. Our results demonstrated a dysregulation of the AMPK/mTOR pathway in hepatocarcinoma cells compared to non-cancerous hepatocytes with a higher expression of mTOR and a lower AMPKα activation in hepatocarcinoma cells. We found that NAMPT inhibition by FK866 significantly activated AMPKα and inhibited the activation of mTOR and its downstream targets p70S6 kinase and 4E-BP1 in hepatocarcinoma cells. Non-cancerous hepatocytes were less sensitive to FK866 and did not show changes in AMPK/mTOR signaling after FK866 treatment. Conclusion: Taken together, these findings reveal an important role of the NAMPT-mediated NAD salvage pathway in the energy homeostasis of hepatocarcinoma cells and suggest NAMPT inhibition as a potential treatment option for HCC. - Highlights: • FK866 increases cell death in p53-deficient hepatocarcinoma cells. • AMPK/mTOR signaling is dysregulated in hepatocarcinoma cells. • FK866-induced NAMPT inhibition activates AMPK�

FK866-induced NAMPT inhibition activates AMPK and downregulates mTOR signaling in hepatocarcinoma cells

International Nuclear Information System (INIS)

Schuster, Susanne; Penke, Melanie; Gorski, Theresa; Gebhardt, Rolf; Weiss, Thomas S.; Kiess, Wieland; Garten, Antje

2015-01-01

Background: Nicotinamide phosphoribosyltransferase (NAMPT) is the key enzyme of the NAD salvage pathway starting from nicotinamide. Cancer cells have an increased demand for NAD due to their high proliferation and DNA repair rate. Consequently, NAMPT is considered as a putative target for anti-cancer therapies. There is evidence that AMP-activated protein kinase (AMPK) and mammalian target of rapamycin (mTOR) become dysregulated during the development of hepatocellular carcinoma (HCC). Here, we investigated the effects of NAMPT inhibition by its specific inhibitor FK866 on the viability of hepatocarcinoma cells and analyzed the effects of FK866 on the nutrient sensor AMPK and mTOR complex1 (mTORC1) signaling. Results: FK866 markedly decreased NAMPT activity and NAD content in hepatocarcinoma cells (Huh7 cells, Hep3B cells) and led to delayed ATP reduction which was associated with increased cell death. These effects could be abrogated by administration of nicotinamide mononucleotide (NMN), the enzyme product of NAMPT. Our results demonstrated a dysregulation of the AMPK/mTOR pathway in hepatocarcinoma cells compared to non-cancerous hepatocytes with a higher expression of mTOR and a lower AMPKα activation in hepatocarcinoma cells. We found that NAMPT inhibition by FK866 significantly activated AMPKα and inhibited the activation of mTOR and its downstream targets p70S6 kinase and 4E-BP1 in hepatocarcinoma cells. Non-cancerous hepatocytes were less sensitive to FK866 and did not show changes in AMPK/mTOR signaling after FK866 treatment. Conclusion: Taken together, these findings reveal an important role of the NAMPT-mediated NAD salvage pathway in the energy homeostasis of hepatocarcinoma cells and suggest NAMPT inhibition as a potential treatment option for HCC. - Highlights: • FK866 increases cell death in p53-deficient hepatocarcinoma cells. • AMPK/mTOR signaling is dysregulated in hepatocarcinoma cells. • FK866-induced NAMPT inhibition activates AMPK�

Acetylcholine promotes the emergence and elongation of lateral roots of Raphanus sativus.

Science.gov (United States)

Sugiyama, Kou-ichi; Tezuka, Takafumi

2011-10-01

Radish (Raphanus sativus L.) was grown on four layers of paper towel moistened with distilled water with and without acetylcholine (ACh) for five days in the dark after sowing. ACh at 1 nM promoted the growth (emergence and elongation) of lateral roots of radish plants, but had no effect on the stems and main roots. Moreover, ACh enhanced the dry weight of roots [main (primary) + lateral roots]. Neostigmine, an inhibitor of acetylcholinesterase (AChE) also promoted the emergence and elongation of lateral roots, and atropine, a competitive inhibitor of ACh receptor, suppressed the emergence and elongation. ACh suppressed the activity of AChE and increased the amount of proteins and pyridine nucleotides (NAD and NADH) in the roots of the seedlings. It also increased the activities of NAD-forming enzymes [NAD synthetase and ATP-nicotinamide mononucleotide (ATP-NMN) adenyltransferase], and enhanced the amount of DNA in the roots of the seedlings. The relationship between ACh and the emergence and growth of lateral roots was discussed from a biochemical viewpoint.

Metabolic Response to NAD Depletion across Cell Lines Is Highly Variable.

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Xiao, Yang; Kwong, Mandy; Daemen, Anneleen; Belvin, Marcia; Liang, Xiaorong; Hatzivassiliou, Georgia; O'Brien, Thomas

2016-01-01

Nicotinamide adenine dinucleotide (NAD) is a cofactor involved in a wide range of cellular metabolic processes and is a key metabolite required for tumor growth. NAMPT, nicotinamide phosphoribosyltransferase, which converts nicotinamide (NAM) to nicotinamide mononucleotide (NMN), the immediate precursor of NAD, is an attractive therapeutic target as inhibition of NAMPT reduces cellular NAD levels and inhibits tumor growth in vivo. However, there is limited understanding of the metabolic response to NAD depletion across cancer cell lines and whether all cell lines respond in a uniform manner. To explore this we selected two non-small cell lung carcinoma cell lines that are sensitive to the NAMPT inhibitor GNE-617 (A549, NCI-H1334), one that shows intermediate sensitivity (NCI-H441), and one that is insensitive (LC-KJ). Even though NAD was reduced in all cell lines there was surprising heterogeneity in their metabolic response. Both sensitive cell lines reduced glycolysis and levels of di- and tri-nucleotides and modestly increased oxidative phosphorylation, but they differed in their ability to combat oxidative stress. H1334 cells activated the stress kinase AMPK, whereas A549 cells were unable to activate AMPK as they contain a mutation in LKB1, which prevents activation of AMPK. However, A549 cells increased utilization of the Pentose Phosphate pathway (PPP) and had lower reactive oxygen species (ROS) levels than H1334 cells, indicating that A549 cells are better able to modulate an increase in oxidative stress. Inherent resistance of LC-KJ cells is associated with higher baseline levels of NADPH and a delayed reduction of NAD upon NAMPT inhibition. Our data reveals that cell lines show heterogeneous response to NAD depletion and that the underlying molecular and genetic framework in cells can influence the metabolic response to NAMPT inhibition.

Metabolic Response to NAD Depletion across Cell Lines Is Highly Variable.

Directory of Open Access Journals (Sweden)

Yang Xiao

Full Text Available Nicotinamide adenine dinucleotide (NAD is a cofactor involved in a wide range of cellular metabolic processes and is a key metabolite required for tumor growth. NAMPT, nicotinamide phosphoribosyltransferase, which converts nicotinamide (NAM to nicotinamide mononucleotide (NMN, the immediate precursor of NAD, is an attractive therapeutic target as inhibition of NAMPT reduces cellular NAD levels and inhibits tumor growth in vivo. However, there is limited understanding of the metabolic response to NAD depletion across cancer cell lines and whether all cell lines respond in a uniform manner. To explore this we selected two non-small cell lung carcinoma cell lines that are sensitive to the NAMPT inhibitor GNE-617 (A549, NCI-H1334, one that shows intermediate sensitivity (NCI-H441, and one that is insensitive (LC-KJ. Even though NAD was reduced in all cell lines there was surprising heterogeneity in their metabolic response. Both sensitive cell lines reduced glycolysis and levels of di- and tri-nucleotides and modestly increased oxidative phosphorylation, but they differed in their ability to combat oxidative stress. H1334 cells activated the stress kinase AMPK, whereas A549 cells were unable to activate AMPK as they contain a mutation in LKB1, which prevents activation of AMPK. However, A549 cells increased utilization of the Pentose Phosphate pathway (PPP and had lower reactive oxygen species (ROS levels than H1334 cells, indicating that A549 cells are better able to modulate an increase in oxidative stress. Inherent resistance of LC-KJ cells is associated with higher baseline levels of NADPH and a delayed reduction of NAD upon NAMPT inhibition. Our data reveals that cell lines show heterogeneous response to NAD depletion and that the underlying molecular and genetic framework in cells can influence the metabolic response to NAMPT inhibition.

Pyridine metabolism and trigonelline synthesis in leaves of the mangrove legume trees Derris indica (Millettia pinnata) and Caesalpinia crista.

Science.gov (United States)

Yin, Yuling; Sasamoto, Hamako; Ashihara, Hiroshi

2011-12-01

The aim of this study was to reveal the pyridine metabolism in leaves of two mangrove legumes, Derris indica (= Millettia pinnata or Pongamia pinnata) and Caesalpinia crista. Radioactivity from [carbonyl-14C]nicotinamide supplied exogenously to young leaf disks was recovered in nicotinic acid, nicotinic acid mononucleotide, NAD, NADP, nicotinamide mononucleotide and trigonelline. These mangrove species, especially D. indica, have strong ability to convert nicotinamide to trigonelline, but not to nicotinic acid glucoside. The endogenous trigonelline content in leaves of D. indica was more than 830 microg/g dry weight. This value is 5-12 times greater than that in leaves of Glycine max. There was little short-term effect of 250 and 500 mM NaCl (equivalent to ca. 50% and 100% sea water) on nicotinamide metabolism.

Novel pathway of NAD metabolism in Aspergillus niger

International Nuclear Information System (INIS)

Kuwahara, Masaaki

1977-01-01

New steps of NAD metabolism were shown in Aspergillus niger. Radioactive nicotinic acid and nicotinamide were incorporated into nicotinamide ribose diphosphate ribose (NAmRDPR), which had been isolated from the culture filtrate. The enzyme preparation of the mold degraded NAmRDPR to form nicotinamide mononucleotide and nicotinic acid under the neutral and alkaline conditions. In the acid extracts of the mycelia grown on the radioactive precursors, high level of radioactivity was detected on NAD. The experimental results showed that the Preiss-Handler pathway and the NAD cycling system function in the NAD biosynthesis in A. niger. A part of the radioactive precursors was also incorporated into nicotinic acid ribonucleoside, which was thought to be formed from nicotinic acid mononucleotide. (auth.)

Comparison and Analysis of 3,4 dihydrocylmandelic acid (DHMA) and noremetanephrine (NMN) on Amyloid-Beta 40 Monomer for treatment of Alzheimer's Disease using Molecular Dynamics Simulation

Science.gov (United States)

Choi, Woosung; Jee, Sang Eun; Jang, Seung Soon

Alzheimer's disease (AD) is type of degenerative dementia caused memory loss and behavior problem. Main reason of AD is Amyloid-Beta 40(A β) mostly composed of α -helix form misfolds to insoluble fibrils and soluble oilgomer. This insoluble fibrils aggregate with beta sheet structure and form the plaque which is caused nurotoxicity in brain. Both 3,4 dihydrocylmandelic acid (DHMA) and noremetanephrine (NMN) are the metabolite of norepinephrine in brain . Also these are inhibit the changing formation of fibrils and maintain the α -helix structure. In this computational modeling study, both NMN and DHMA molecules were modified and analyzed for specific effect on the A β-monomer using molecular dynamics simulation. Using molecular dynamic simulation, NMN and DHMA act as modulator on three A β-monomer batches and could observe the conformational changing of these A β-monomer under the physiologocal condition. This computational experiment is designed to compare and analyze both of chemicals for determining which chamecal would be more effective on the conformation of A β 40 monomer.

Nicotinamide extends replicative lifespan of human cells.

Science.gov (United States)

Kang, Hyun Tae; Lee, Hyung Il; Hwang, Eun Seong

2006-10-01

We found that an ongoing application of nicotinamide to normal human fibroblasts not only attenuated expression of the aging phenotype but also increased their replicative lifespan, causing a greater than 1.6-fold increase in the number of population doublings. Although nicotinamide by itself does not act as an antioxidant, the cells cultured in the presence of nicotinamide exhibited reduced levels of reactive oxygen species (ROS) and oxidative damage products associated with cellular senescence, and a decelerated telomere shortening rate without a detectable increase in telomerase activity. Furthermore, in the treated cells growing beyond the original Hayflick limit, the levels of p53, p21WAF1, and phospho-Rb proteins were similar to those in actively proliferating cells. The nicotinamide treatment caused a decrease in ATP levels, which was stably maintained until the delayed senescence point. Nicotinamide-treated cells also maintained high mitochondrial membrane potential but a lower respiration rate and superoxide anion level. Taken together, in contrast to its demonstrated pro-aging effect in yeast, nicotinamide extends the lifespan of human fibroblasts, possibly through reduction in mitochondrial activity and ROS production.

Generation, Release, and Uptake of the NAD Precursor Nicotinic Acid Riboside by Human Cells.

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Kulikova, Veronika; Shabalin, Konstantin; Nerinovski, Kirill; Dölle, Christian; Niere, Marc; Yakimov, Alexander; Redpath, Philip; Khodorkovskiy, Mikhail; Migaud, Marie E; Ziegler, Mathias; Nikiforov, Andrey

2015-11-06

NAD is essential for cellular metabolism and has a key role in various signaling pathways in human cells. To ensure proper control of vital reactions, NAD must be permanently resynthesized. Nicotinamide and nicotinic acid as well as nicotinamide riboside (NR) and nicotinic acid riboside (NAR) are the major precursors for NAD biosynthesis in humans. In this study, we explored whether the ribosides NR and NAR can be generated in human cells. We demonstrate that purified, recombinant human cytosolic 5'-nucleotidases (5'-NTs) CN-II and CN-III, but not CN-IA, can dephosphorylate the mononucleotides nicotinamide mononucleotide and nicotinic acid mononucleotide (NAMN) and thus catalyze NR and NAR formation in vitro. Similar to their counterpart from yeast, Sdt1, the human 5'-NTs require high (millimolar) concentrations of nicotinamide mononucleotide or NAMN for efficient catalysis. Overexpression of FLAG-tagged CN-II and CN-III in HEK293 and HepG2 cells resulted in the formation and release of NAR. However, NAR accumulation in the culture medium of these cells was only detectable under conditions that led to increased NAMN production from nicotinic acid. The amount of NAR released from cells engineered for increased NAMN production was sufficient to maintain viability of surrounding cells unable to use any other NAD precursor. Moreover, we found that untransfected HeLa cells produce and release sufficient amounts of NAR and NR under normal culture conditions. Collectively, our results indicate that cytosolic 5'-NTs participate in the conversion of NAD precursors and establish NR and NAR as integral constituents of human NAD metabolism. In addition, they point to the possibility that different cell types might facilitate each other's NAD supply by providing alternative precursors. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

TGFBR2 and BAX mononucleotide tract mutations, microsatellite instability, and prognosis in 1072 colorectal cancers.

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Kaori Shima

Full Text Available Mononucleotide tracts in the coding regions of the TGFBR2 and BAX genes are commonly mutated in microsatellite instability-high (MSI-high colon cancers. The receptor TGFBR2 plays an important role in the TGFB1 (transforming growth factor-β, TGF-β signaling pathway, and BAX plays a key role in apoptosis. However, a role of TGFBR2 or BAX mononucleotide mutation in colorectal cancer as a prognostic biomarker remains uncertain.We utilized a database of 1072 rectal and colon cancers in two prospective cohort studies (the Nurses' Health Study and the Health Professionals Follow-up Study. Cox proportional hazards model was used to compute mortality hazard ratio (HR, adjusted for clinical, pathological and molecular features including the CpG island methylator phenotype (CIMP, LINE-1 methylation, and KRAS, BRAF and PIK3CA mutations. MSI-high was observed in 15% (162/1072 of all colorectal cancers. TGFBR2 and BAX mononucleotide mutations were detected in 74% (117/159 and 30% (48/158 of MSI-high tumors, respectively. In Kaplan-Meier analysis as well as univariate and multivariate Cox regression analyses, compared to microsatellite stable (MSS/MSI-low cases, MSI-high cases were associated with superior colorectal cancer-specific survival [adjusted HR, 0.34; 95% confidence interval (CI, 0.20-0.57] regardless of TGFBR2 or BAX mutation status. Among MSI-high tumors, TGFBR2 mononucleotide mutation was associated with CIMP-high independent of other variables [multivariate odds ratio, 3.57; 95% CI, 1.66-7.66; p = 0.0011].TGFBR2 or BAX mononucleotide mutations are not associated with the patient survival outcome in MSI-high colorectal cancer. Our data do not support those mutations as prognostic biomarkers (beyond MSI in colorectal carcinoma.

An open-label, non-randomized study of the pharmacokinetics of the nutritional supplement nicotinamide riboside (NR) and its effects on blood NAD+ levels in healthy volunteers.

Science.gov (United States)

Airhart, Sophia E; Shireman, Laura M; Risler, Linda J; Anderson, Gail D; Nagana Gowda, G A; Raftery, Daniel; Tian, Rong; Shen, Danny D; O'Brien, Kevin D

2017-01-01

The co-primary objectives of this study were to determine the human pharmacokinetics (PK) of oral NR and the effect of NR on whole blood nicotinamide adenine dinucleotide (NAD+) levels. Though mitochondrial dysfunction plays a critical role in the development and progression of heart failure, no mitochondria-targeted therapies have been translated into clinical practice. Recent murine studies have reported associations between imbalances in the NADH/NAD+ ratio with mitochondrial dysfunction in multiple tissues, including myocardium. Moreover, an NAD+ precursor, nicotinamide mononucleotide, improved cardiac function, while another NAD+ precursor, nicotinamide riboside (NR), improved mitochondrial function in muscle, liver and brown adipose. Thus, PK studies of NR in humans is critical for future clinical trials. In this non-randomized, open-label PK study of 8 healthy volunteers, 250 mg NR was orally administered on Days 1 and 2, then uptitrated to peak dose of 1000 mg twice daily on Days 7 and 8. On the morning of Day 9, subjects completed a 24-hour PK study after receiving 1000 mg NR at t = 0. Whole-blood levels of NR, clinical blood chemistry, and NAD+ levels were analyzed. Oral NR was well tolerated with no adverse events. Significant increases comparing baseline to mean concentrations at steady state (Cave,ss) were observed for both NR (p = 0.03) and NAD+ (p = 0.001); the latter increased by 100%. Absolute changes from baseline to Day 9 in NR and NAD+ levels correlated highly (R2 = 0.72, p = 0.008). Because NR increases circulating NAD+ in humans, NR may have potential as a therapy in patients with mitochondrial dysfunction due to genetic and/or acquired diseases.

An open-label, non-randomized study of the pharmacokinetics of the nutritional supplement nicotinamide riboside (NR and its effects on blood NAD+ levels in healthy volunteers.

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Sophia E Airhart

Full Text Available The co-primary objectives of this study were to determine the human pharmacokinetics (PK of oral NR and the effect of NR on whole blood nicotinamide adenine dinucleotide (NAD+ levels.Though mitochondrial dysfunction plays a critical role in the development and progression of heart failure, no mitochondria-targeted therapies have been translated into clinical practice. Recent murine studies have reported associations between imbalances in the NADH/NAD+ ratio with mitochondrial dysfunction in multiple tissues, including myocardium. Moreover, an NAD+ precursor, nicotinamide mononucleotide, improved cardiac function, while another NAD+ precursor, nicotinamide riboside (NR, improved mitochondrial function in muscle, liver and brown adipose. Thus, PK studies of NR in humans is critical for future clinical trials.In this non-randomized, open-label PK study of 8 healthy volunteers, 250 mg NR was orally administered on Days 1 and 2, then uptitrated to peak dose of 1000 mg twice daily on Days 7 and 8. On the morning of Day 9, subjects completed a 24-hour PK study after receiving 1000 mg NR at t = 0. Whole-blood levels of NR, clinical blood chemistry, and NAD+ levels were analyzed.Oral NR was well tolerated with no adverse events. Significant increases comparing baseline to mean concentrations at steady state (Cave,ss were observed for both NR (p = 0.03 and NAD+ (p = 0.001; the latter increased by 100%. Absolute changes from baseline to Day 9 in NR and NAD+ levels correlated highly (R2 = 0.72, p = 0.008.Because NR increases circulating NAD+ in humans, NR may have potential as a therapy in patients with mitochondrial dysfunction due to genetic and/or acquired diseases.

Nicotinamide pharmacokinetics in humans and mice

International Nuclear Information System (INIS)

Horsman, M.R.; Hoyer, M.; Overgaard, J.; Honess, D.J.; Dennis, A.F.

1993-01-01

Healthy human volunteers orally ingested escalating doses of up to 6 g nicotinamide in capsule form on an empty stomach. Some side-effects were seen although these were mild and transient. HPLC analysis of blood samples showed peak plasma levels, typically within 45 min after ingestion, which were linearly dependent on dose ingested. The elimination half-life and AUC were also found to increase with drug dose, although these increases were non-linear. Pharmacokinetic studies were also performed to female CDF1 mice with C3H mammary carcinomas grown in the right rear foot. Analysis of blood and tumour samples taken from mice injected i.p. with nicotinamide doses between 100-1000 mg/kg showed similar characteristics as the human data, although the elimination half-lives were not dose-dependent. The average peak plasma concentration of 160 μg/ml measured in humans after taking 6 g of nicotinamide was equivalent to that seen in mice after injecting 171 mg/kg. Using a regrowth delay assay the enhancement of radiation damage by nicotinamide in this mouse tumour was found to be independent of drug dose from 100-1000 mg/kg, resulting in a constant 1.3-fold increase in radiation response. Doses of nicotinamide that can be tolerated clinically should therefore produce adequate enhancements of radiation damage in human tumours. (author)

Yeast Interacting Proteins Database: YLR328W, YGR010W [Yeast Interacting Proteins Database

Lifescience Database Archive (English)

Full Text Available YLR328W NMA1 Nicotinic acid mononucleotide adenylyltransferase, involved in pathways... of NAD biosynthesis, including the de novo, NAD(+) salvage, and nicotinamide riboside salvage pathways Row... ORF YLR328W Bait gene name NMA1 Bait description Nicotinic acid mononucleotide adenylyltransferase, involved in pathways...otinamide riboside salvage pathways Rows with this bait as bait Rows with this bait as bait (2) Rows with th

Evaluation of nicotinamide microemulsion on the skin penetration enhancement.

Science.gov (United States)

Boonme, Prapaporn; Boonthongchuay, Chalida; Wongpoowarak, Wibul; Amnuaikit, Thanaporn

2016-01-01

This study purposed to evaluate a microemulsion containing nicotinamide for its characteristics, stability, and skin penetration and retention comparing with a solution of nicotinamide in 2:1 mixture of water and isopropyl alcohol (IPA). The microemulsion system was composed of 1:1 mixture of Span80 and Tween80 as a surfactant mixture, isopropyl palmitate (IPP) as an oil phase, and 2:1 mixture of water and IPA as an aqueous phase. Nicotinamide microemulsion was prepared by dissolving the active in the aqueous phase before simply mixing with the other components. It was determined for its characteristics and stability under various conditions. The skin penetration and retention studies of nicotinamide microemulsion and solution were performed by modified Franz diffusion cells, using newborn pig skin as the membrane. The results showed that nicotinamide microemulsion could be obtained as clear yellowish liquid, was water-in-oil (w/o) type, possessed Newtonian flow, and exhibited physicochemical stability when kept at 4 °C and room temperature (≈30 ± 2 °C) during 3 months. From the skin penetration data, the microemulsion could enhance the skin penetration of nicotinamide comparing with the solution. Additionally, nicotinamide microemulsion could provide much higher amount of skin retention than that of skin penetration, resulting in suitability for a cosmeceutical product.

21 CFR 573.625 - Menadione nicotinamide bisulfite.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Menadione nicotinamide bisulfite. 573.625 Section 573.625 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... ANIMALS Food Additive Listing § 573.625 Menadione nicotinamide bisulfite. The food additive may be safely...

Nicotinamide exacerbates hypoxemia in ventilator-induced lung injury independent of neutrophil infiltration.

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Heather D Jones

Full Text Available Ventilator-induced lung injury is a form of acute lung injury that develops in critically ill patients on mechanical ventilation and has a high degree of mortality. Nicotinamide phosphoribosyltransferase is an enzyme that is highly upregulated in ventilator-induced lung injury and exacerbates the injury when given exogenously. Nicotinamide (vitamin B3 directly inhibits downstream pathways activated by Nicotinamide phosphoribosyltransferase and is protective in other models of acute lung injury.We administered nicotinamide i.p. to mice undergoing mechanical ventilation with high tidal volumes to study the effects of nicotinamide on ventilator-induced lung injury. Measures of injury included oxygen saturations and bronchoalveolar lavage neutrophil counts, protein, and cytokine levels. We also measured expression of nicotinamide phosophoribosyltransferase, and its downstream effectors Sirt1 and Cebpa, Cebpb, Cebpe. We assessed the effect of nicotinamide on the production of nitric oxide during ventilator-induced lung injury. We also studied the effects of ventilator-induced lung injury in mice deficient in C/EBPε.Nicotinamide treatment significantly inhibited neutrophil infiltration into the lungs during ventilator-induced lung injury, but did not affect protein leakage or cytokine production. Surprisingly, mice treated with nicotinamide developed significantly worse hypoxemia during mechanical ventilation. This effect was not linked to increases in nitric oxide production or alterations in expression of Nicotinamide phosphoribosyl transferase, Sirt1, or Cebpa and Cebpb. Cebpe mRNA levels were decreased with either nicotinamide treatment or mechanical ventilation, but mice lacking C/EBPε developed the same degree of hypoxemia and ventilator-induced lung injury as wild-type mice.Nicotinamide treatment during VILI inhibits neutrophil infiltration of the lungs consistent with a strong anti-inflammatory effect, but paradoxically also leads to the

Nicotinamide -Methyltransferase in Health and Cancer

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David B Ramsden

2017-06-01

Full Text Available Over the past decade, the roles of nicotinamide N -methyltransferase and its product 1-methyl nicotinamide have emerged from playing merely minor roles in phase 2 xenobiotic metabolism as actors in some of the most important scenes of human life. In this review, the structures of the gene, messenger RNA, and protein are discussed, together with the role of the enzyme in many of the common cancers that afflict people today.

The NAD(+) precursor nicotinamide riboside decreases exercise performance in rats.

Science.gov (United States)

Kourtzidis, Ioannis A; Stoupas, Andreas T; Gioris, Ioannis S; Veskoukis, Aristidis S; Margaritelis, Nikos V; Tsantarliotou, Maria; Taitzoglou, Ioannis; Vrabas, Ioannis S; Paschalis, Vassilis; Kyparos, Antonios; Nikolaidis, Michalis G

2016-01-01

Nicotinamide adenine dinucleotide (NAD(+)) and its phosphorylated form (NADP(+)) are key molecules in ubiquitous bioenergetic and cellular signaling pathways, regulating cellular metabolism and homeostasis. Thus, supplementation with NAD(+) and NADP(+) precursors emerged as a promising strategy to gain many and multifaceted health benefits. In this proof-of-concept study, we sought to investigate whether chronic nicotinamide riboside administration (an NAD(+) precursor) affects exercise performance. Eighteen Wistar rats were equally divided in two groups that received either saline vehicle or nicotinamide riboside at a dose of 300 mg/kg body weight/day for 21 days via gavage. At the end of the 21-day administration protocol, both groups performed an incremental swimming performance test. The nicotinamide riboside group showed a tendency towards worse physical performance by 35 % compared to the control group at the final 10 % load (94 ± 53 s for the nicotinamide riboside group and 145 ± 59 s for the control group; P = 0.071). Our results do not confirm the previously reported ergogenic effect of nicotinamide riboside. The potentially negative effect of nicotinamide riboside administration on physical performance may be attributed to the pleiotropic metabolic and redox properties of NAD(+) and NADP(+).

Nicotinamide riboside kinase structures reveal new pathways to NAD+.

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Wolfram Tempel

2007-10-01

Full Text Available The eukaryotic nicotinamide riboside kinase (Nrk pathway, which is induced in response to nerve damage and promotes replicative life span in yeast, converts nicotinamide riboside to nicotinamide adenine dinucleotide (NAD+ by phosphorylation and adenylylation. Crystal structures of human Nrk1 bound to nucleoside and nucleotide substrates and products revealed an enzyme structurally similar to Rossmann fold metabolite kinases and allowed the identification of active site residues, which were shown to be essential for human Nrk1 and Nrk2 activity in vivo. Although the structures account for the 500-fold discrimination between nicotinamide riboside and pyrimidine nucleosides, no enzyme feature was identified to recognize the distinctive carboxamide group of nicotinamide riboside. Indeed, nicotinic acid riboside is a specific substrate of human Nrk enzymes and is utilized in yeast in a novel biosynthetic pathway that depends on Nrk and NAD+ synthetase. Additionally, nicotinic acid riboside is utilized in vivo by Urh1, Pnp1, and Preiss-Handler salvage. Thus, crystal structures of Nrk1 led to the identification of new pathways to NAD+.

Structural Basis of Substrate Recognition in Human Nicotinamide N-Methyltransferase

Energy Technology Data Exchange (ETDEWEB)

Peng, Yi; Sartini, Davide; Pozzi, Valentina; Wilk, Dennis; Emanuelli, Monica; Yee, Vivien C. (Case Western); (Politecnica Valencia)

2012-05-02

Nicotinamide N-methyltransferase (NNMT) catalyzes the N-methylation of nicotinamide, pyridines, and other analogues using S-adenosyl-L-methionine as donor. NNMT plays a significant role in the regulation of metabolic pathways and is expressed at markedly high levels in several kinds of cancers, presenting it as a potential molecular target for cancer therapy. We have determined the crystal structure of human NNMT as a ternary complex bound to both the demethylated donor S-adenosyl-L-homocysteine and the acceptor substrate nicotinamide, to 2.7 {angstrom} resolution. These studies reveal the structural basis for nicotinamide binding and highlight several residues in the active site which may play roles in nicotinamide recognition and NNMT catalysis. The functional importance of these residues was probed by mutagenesis. Of three residues near the nicotinamide's amide group, substitution of S201 and S213 had no effect on enzyme activity while replacement of D197 dramatically decreased activity. Substitutions of Y20, whose side chain hydroxyl interacts with both the nicotinamide aromatic ring and AdoHcy carboxylate, also compromised activity. Enzyme kinetics analysis revealed k{sub cat}/K{sub m} decreases of 2-3 orders of magnitude for the D197A and Y20A mutants, confirming the functional importance of these active site residues. The mutants exhibited substantially increased K{sub m} for both NCA and AdoMet and modestly decreased k{sub cat}. MD simulations revealed long-range conformational effects which provide an explanation for the large increase in K{sub m}(AdoMet) for the D197A mutant, which interacts directly only with nicotinamide in the ternary complex crystal structure.

A biomimetic redox flow battery based on flavin mononucleotide

OpenAIRE

Orita, A; Verde, MG; Sakai, M; Meng, YS

2016-01-01

The versatility in design of redox flow batteries makes them apt to efficiently store energy in large-scale applications at low cost. The discovery of inexpensive organic electroactive materials for use in aqueous flow battery electrolytes is highly attractive, but is thus far limited. Here we report on a flow battery using an aqueous electrolyte based on the sodium salt of flavin mononucleotide. Flavins are highly versatile electroactive molecules, which catalyse a multitude of redox reactio...

4-Hydroxy-3-methoxybenzaldehyde–nicotinamide (1/1

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Fiona N.-F. How

2011-12-01

Full Text Available In the title compound, C6H6N2O·C8H8O3, an equimolar co-crystal of nicotinamide and vanillin, the aromatic ring and the amide fragment of the nicotinamide molecule make a dihedral angle of 32.6 (2°. The vanillin molecule is almost planar, with an r.m.s. deviation for all non-H atoms of 0.0094 Å. The vaniline and nicotinamide aromatic rings are nearly coplanar, the dihedral angle between them being 3.20 (9°. In the crystal, the two components are linked through N—H...O and O—H...N hydrogen bonds into chains along the a axis. The chains are connected via C—H...O interactions, forming a three-dimensional polymeric structure.

Characterization of CobB kinetics and inhibition by nicotinamide.

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Julia Gallego-Jara

Full Text Available Lysine acetylation has emerged as a global protein regulation system in all domains of life. Sirtuins, or Sir2-like enzymes, are a family of histone deacetylases characterized by their employing NAD+ as a co-substrate. Sirtuins can deacetylate several acetylated proteins, but a consensus substrate recognition sequence has not yet been established. Product inhibition of many eukaryotic sirtuins by nicotinamide and its analogues has been studied in vitro due to their potential role as anticancer agents. In this work, the kinetics of CobB, the main Escherichia coli deacetylase, have been characterized. To our knowledge, this is the first kinetic characterization of a sirtuin employing a fully acetylated and natively folded protein as a substrate. CobB deacetylated several acetyl-CoA synthetase acetylated lysines with a single kinetic rate. In addition, in vitro nicotinamide inhibition of CobB has been characterized, and the intracellular nicotinamide concentrations have been determined under different growth conditions. The results suggest that nicotinamide can act as a CobB regulator in vivo. A nicotinamidase deletion strain was thus phenotypically characterized, and it behaved similarly to the ΔcobB strain. The results of this work demonstrate the potential regulatory role of the nicotinamide metabolite in vivo.

Characterization of CobB kinetics and inhibition by nicotinamide.

Science.gov (United States)

Gallego-Jara, Julia; Écija Conesa, Ana; de Diego Puente, Teresa; Lozano Terol, Gema; Cánovas Díaz, Manuel

2017-01-01

Lysine acetylation has emerged as a global protein regulation system in all domains of life. Sirtuins, or Sir2-like enzymes, are a family of histone deacetylases characterized by their employing NAD+ as a co-substrate. Sirtuins can deacetylate several acetylated proteins, but a consensus substrate recognition sequence has not yet been established. Product inhibition of many eukaryotic sirtuins by nicotinamide and its analogues has been studied in vitro due to their potential role as anticancer agents. In this work, the kinetics of CobB, the main Escherichia coli deacetylase, have been characterized. To our knowledge, this is the first kinetic characterization of a sirtuin employing a fully acetylated and natively folded protein as a substrate. CobB deacetylated several acetyl-CoA synthetase acetylated lysines with a single kinetic rate. In addition, in vitro nicotinamide inhibition of CobB has been characterized, and the intracellular nicotinamide concentrations have been determined under different growth conditions. The results suggest that nicotinamide can act as a CobB regulator in vivo. A nicotinamidase deletion strain was thus phenotypically characterized, and it behaved similarly to the ΔcobB strain. The results of this work demonstrate the potential regulatory role of the nicotinamide metabolite in vivo.

pHP-Tethered N-Acyl Carbamate: A Photocage for Nicotinamide.

Science.gov (United States)

Salahi, Farbod; Purohit, Vatsal; Ferraudi, Guillermo; Stauffacher, Cynthia; Wiest, Olaf; Helquist, Paul

2018-05-04

The synthesis of a new photocaged nicotinamide having an N-acyl carbamate linker and a p-hydroxyphenacyl (pHP) chromophore is described. The photophysical and photochemical studies showed an absorption maximum at λ = 330 nm and a quantum yield for release of 11% that are dependent upon both pH and solvent. While the acyl carbamate releases nicotinamide efficiently, a simpler amide linker was inert to photocleavage. This photocaged nicotinamide has significant advantages with respect to quantum yield, absorbance wavelength, rate of release, and solubility that make it the first practical example of a photocaged amide.

Prevention of photoimmunosuppression and photocarcinogenesis by topical nicotinamide

International Nuclear Information System (INIS)

Gensler, H.L.

1997-01-01

Ultraviolet (UV) B irradiation leads to a potent immunosuppression of the capacity to reject syngeneic, antigenic tumors. If this immunosuppression is critical for the development of most skin tumors, then its prevention should result in prevention of photocarcinogenesis. We previously showed a correlation between the inhibition of photoimmunosuppression and prevention of photocarcinogenesis by dl-alpha-tocopherol, tannic acid, or alpha-difluoro methylornithine. The current study was designed to determine whether topical nicotinamide, the active form of vitamin B-3, or niacin, prevents immunosuppression and skin cancer in UV-irradiated mice. In a passive transfer assay for immunosuppression, splenocytes from UV-irradiated mice enhanced the growth of antigenic tumor challenges in recipient mice. Treatment of the UV-irradiated mice with 40 micromoles of nicotinamide twice weekly starting two weeks before UV irradiation and throughout the experiment prevented this immunosuppresion. UVB irradiation consisted of five weekly 30-minute exposures to banks of six FS40 Westinghouse fluorescent sunlamps. Mice received approximatety 6.2 x 10(5) J/m(2) in the passive transfer assays and 1.09 x 10(6) J/m(2) in the photocarcinogenesis studies. Application of nicotinamide to UV-irradiated mice reduced skin tumor incidence from 75% to 42.5% (p = 0.016, Cox proportional hazards analysis). Thus topical nicotinamide prevented the immunosuppression and skin tumor induction by UVB irradiation

Cyclic voltammetric response of nicotinic acid and nicotinamide on a polycrystalline gold electrode

International Nuclear Information System (INIS)

Wang Xiaoxia; Yang Nianjun; Wan Qijin

2006-01-01

The oxidation of nicotinic acid and nicotinamide on a polycrystalline gold electrode occurred at almost same potentials but their reduction did at different peak potentials. The redox reaction mechanisms of nicotinic acid and nicotinamide were rationalized by the formation/disappearance of the new nitrogen-oxygen bonds in the pyridine rings by means of cyclic voltammetry and bulk electrolysis. The anodic currents of nicotinic acid and nicotinamide were controlled by diffusion, while the cathodic ones by adsorption. The difference in the cathodic peak potentials of nicotinic acid and nicotinamide on the polycrystalline gold electrode is attributed to the effect of the electron densities of remote substituents on the pyridine rings. The cathodic peak currents at about 0.20 V were linear with their concentrations in the range of 2.4 mM to 2.7 μM and 2.4 mM to 3.3 μM with detection limits of 0.27 and 0.33 μM for nicotinic acid and nicotinamide, respectively. Voltammetry was then adopted for the selective monitoring the content of nicotinic acid and nicotinamide in pharmaceuticals

European Nicotinamide Diabetes Intervention Trial (ENDIT)

DEFF Research Database (Denmark)

Gale, E A M; Bingley, P J; Emmett, C L

2004-01-01

with a pseudorandom number generator and we used size balanced blocks of four and stratified by age and national group. Primary outcome was development of diabetes, as defined by WHO criteria. Analysis was done on an intention-to-treat basis. FINDINGS: There was no difference in the development of diabetes between...... secretion. INTERPRETATION: Large-scale controlled trials of interventions designed to prevent the onset of type 1 diabetes are feasible, but nicotinamide was ineffective at the dose we used.......BACKGROUND: Results of studies in animals and human beings suggest that type 1 diabetes is preventable. Nicotinamide prevents autoimmune diabetes in animal models, possibly through inhibition of the DNA repair enzyme poly-ADP-ribose polymerase and prevention of beta-cell NAD depletion. We aimed...

Meat and Nicotinamide: A Causal Role in Human Evolution, History, and Demographics

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Adrian C Williams

2017-04-01

Full Text Available Hunting for meat was a critical step in all animal and human evolution. A key brain-trophic element in meat is vitamin B 3 /nicotinamide. The supply of meat and nicotinamide steadily increased from the Cambrian origin of animal predators ratcheting ever larger brains. This culminated in the 3-million-year evolution of Homo sapiens and our overall demographic success. We view human evolution, recent history, and agricultural and demographic transitions in the light of meat and nicotinamide intake. A biochemical and immunological switch is highlighted that affects fertility in the ‘de novo’ tryptophan-to-kynurenine-nicotinamide ‘immune tolerance’ pathway. Longevity relates to nicotinamide adenine dinucleotide consumer pathways. High meat intake correlates with moderate fertility, high intelligence, good health, and longevity with consequent population stability, whereas low meat/high cereal intake (short of starvation correlates with high fertility, disease, and population booms and busts. Too high a meat intake and fertility falls below replacement levels. Reducing variances in meat consumption might help stabilise population growth and improve human capital.

Deracemization of Axially Chiral Nicotinamides by Dynamic Salt Formation with Enantiopure Dibenzoyltartaric Acid (DBTA

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Fumitoshi Yagishita

2013-11-01

Full Text Available Dynamic atroposelective resolution of chiral salts derived from oily racemic nicotinamides and enantiopure dibenzoyltartaric acid (DBTA was achieved by crystallization. The absolute structures of the axial chiral nicotinamides were determined by X-ray structural analysis. The chirality could be controlled by the selection of enantiopure DBTA as a chiral auxiliary. The axial chirality generated by dynamic salt formation was retained for a long period after dissolving the chiral salt in solution even after removal of the chiral acid. The rate of racemization of nicotinamides could be controlled based on the temperature and solvent properties, and that of the salts was prolonged compared to free nicotinamides, as the molecular structure of the pyridinium ion in the salts was different from that of acid-free nicotinamides.

Nicotinamide induces differentiation of embryonic stem cells into insulin-secreting cells

International Nuclear Information System (INIS)

Vaca, Pilar; Berna, Genoveva; Araujo, Raquel; Carneiro, Everardo M.; Bedoya, Francisco J.; Soria, Bernat; Martin, Franz

2008-01-01

The poly(ADP-ribose) polymerase (PARP) inhibitor, nicotinamide, induces differentiation and maturation of fetal pancreatic cells. In addition, we have previously reported evidence that nicotinamide increases the insulin content of cells differentiated from embryonic stem (ES) cells, but the possibility of nicotinamide acting as a differentiating agent on its own has never been completely explored. Islet cell differentiation was studied by: (i) X-gal staining after neomycin selection; (ii) BrdU studies; (iii) single and double immunohistochemistry for insulin, C-peptide and Glut-2; (iv) insulin and C-peptide content and secretion assays; and (v) transplantation of differentiated cells, under the kidney capsule, into streptozotocin (STZ)-diabetic mice. Here we show that undifferentiated mouse ES cells treated with nicotinamide: (i) showed an 80% decrease in cell proliferation; (ii) co-expressed insulin, C-peptide and Glut-2; (iii) had values of insulin and C-peptide corresponding to 10% of normal mouse islets; (iv) released insulin and C-peptide in response to stimulatory glucose concentrations; and (v) after transplantation into diabetic mice, normalized blood glucose levels over 7 weeks. Our data indicate that nicotinamide decreases ES cell proliferation and induces differentiation into insulin-secreting cells. Both aspects are very important when thinking about cell therapy for the treatment of diabetes based on ES cells

A Mononucleotide Markers Panel to Identify hMLH1/hMSH2 Germline Mutations

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M. Pedroni

2007-01-01

Full Text Available Hereditary NonPolyposis Colorectal Cancer (Lynch syndrome is an autosomal dominant disease caused by germline mutations in a class of genes deputed to maintain genomic integrity during cell replication, mutations result in a generalized genomic instability, particularly evident at microsatellite loci (Microsatellite Instability, MSI. MSI is present in 85–90% of colorectal cancers that occur in Lynch Syndrome. To standardize the molecular diagnosis of MSI, a panel of 5 microsatellite markers was proposed (known as the “Bethesda panel”. Aim of our study is to evaluate if MSI testing with two mononucleotide markers, such as BAT25 and BAT26, was sufficient to identify patients with hMLH1/hMSH2 germline mutations. We tested 105 tumours for MSI using both the Bethesda markers and the two mononucleotide markers BAT25 and BAT26. Moreover, immunohistochemical evaluation of MLH1 and MSH2 proteins was executed on the tumours with at least one unstable microsatellite, whereas germline hMLH1/hMSH2 mutations were searched for all cases showing two or more unstable microsatellites.

Cyclic mononucleotides modulate potassium and calcium flux responses to H2O2 in Arabidopsis roots

KAUST Repository

Ordoñez, Natalia Maria

2014-02-13

Cyclic mononucleotides are messengers in plant stress responses. Here we show that hydrogen peroxide (H2O2) induces rapid net K+-efflux and Ca2+-influx in Arabidopsis roots. Pre-treatment with either 10 μM cAMP or cGMP for 1 or 24 h does significantly reduce net K+-leakage and Ca2+-influx, and in the case of the K+-fluxes, the cell permeant cyclic mononucleotides are more effective. We also examined the effect of 10 μM of the cell permeant 8-Br-cGMP on the Arabidopsis microsomal proteome and noted a specific increase in proteins with a role in stress responses and ion transport, suggesting that cGMP is sufficient to directly and/or indirectly induce complex adaptive changes to cellular stresses induced by H2O2. © 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

NAD+ biosynthesis, aging, and disease [version 1; referees: 2 approved

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Sean Johnson

2018-02-01

Full Text Available Nicotinamide adenine dinucleotide (NAD+ biosynthesis and its regulation have recently been attracting markedly increasing interest. Aging is marked by a systemic decrease in NAD+ across multiple tissues. The dysfunction of NAD+ biosynthesis plays a critical role in the pathophysiologies of multiple diseases, including age-associated metabolic disorders, neurodegenerative diseases, and mental disorders. As downstream effectors, NAD+-dependent enzymes, such as sirtuins, are involved in the progression of such disorders. These recent studies implicate NAD+ biosynthesis as a potential target for preventing and treating age-associated diseases. Indeed, new studies have demonstrated the therapeutic potential of supplementing NAD+ intermediates, such as nicotinamide mononucleotide and nicotinamide riboside, providing a proof of concept for the development of an effective anti-aging intervention.

Radiotherapy and chemotherapy with or without carbogen and nicotinamide in inoperable biopsy-proven glioblastoma multiforme

International Nuclear Information System (INIS)

Simon, Jean-Marc; Noeel, Georges; Chiras, Jacques; Khe, H.-X.; Delattre, Jean-Yves; Baillet, Francois; Mazeron, Jean-Jacques

2003-01-01

Background: Nicotinamide and carbogen have been shown to enhance the radiation effect in tumour models. Purpose: Prospective evaluation of the toxicity and efficacy of carbogen and nicotinamide with external beam radiotherapy in the management of inoperable glioblastoma. Patients and methods: From April 1995 to December 1997, 33 patients with inoperable biopsy-proven glioblastoma multiforme (GBM) were enrolled in a phase II trial, to undergo radiotherapy (59.4 Gy in 1.8 Gy/fraction), intra-arterial cerebral chemotherapy (ACNU 100 mg/m 2 , three cycles), carbogen breathing (15 l/min), and nicotinamide (85 mg/kg). This experimental group was compared to a control group of 38 patients with inoperable GBM treated with radiotherapy and three cycles of nitrosourea-based chemotherapy from January 1990 to March 1995, in our institution. Results: In the experimental group, carbogen breathing was well tolerated, but only 51.5% of patients completed daily nicotinamide over the 6.5-week treatment period. Nausea and vomiting were the most frequent side effects of nicotinamide. No significant difference in overall survival was observed among the two treatment groups: median survival times were 36.7 and 35.3 weeks for patients treated with carbogen and nicotinamide, and for those treated in the control group, respectively. Conclusion: The association of carbogen and nicotinamide with radiotherapy is feasible, but tolerable only in 51.5% of patients with GBM. Carbogen and nicotinamide did not appear to modify the evolution of glioblastoma

Analysis of Escherichia coli nicotinate mononucleotide adenylyltransferase mutants in vivo and in vitro

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Rydén-Aulin Monica

2005-09-01

Full Text Available Abstract Background Adenylation of nicotinate mononucleotide to nicotinate adenine dinucleotide is the penultimate step in NAD+ synthesis. In Escherichia coli, the enzyme nicotinate mononucleotide adenylyltransferase is encoded by the nadD gene. We have earlier made an initial characterization in vivo of two mutant enzymes, NadD72 and NadD74. Strains with either mutation have decreased intracellular levels of NAD+, especially for one of the alleles, nadD72. Results In this study these two mutant proteins have been further characterized together with ten new mutant variants. Of the, in total, twelve mutations four are in a conserved motif in the C-terminus and eight are in the active site. We have tested the activity of the enzymes in vitro and their effect on the growth phenotype in vivo. There is a very good correlation between the two data sets. Conclusion The mutations in the C-terminus did not reveal any function for the conserved motif. On the other hand, our data has lead us to assign amino acid residues His-19, Arg-46 and Asp-109 to the active site. We have also shown that the nadD gene is essential for growth in E. coli.

Glaucoma as a Metabolic Optic Neuropathy: Making the Case for Nicotinamide Treatment in Glaucoma.

Science.gov (United States)

Williams, Pete A; Harder, Jeffrey M; John, Simon W M

2017-12-01

Mitochondrial dysfunction may be an important, if not essential, component of human glaucoma. Using transcriptomics followed by molecular and neurobiological techniques, we have recently demonstrated that mitochondrial dysfunction within retinal ganglion cells is an early feature in the DBA/2J mouse model of inherited glaucoma. Guided by these findings, we discovered that the retinal level of nicotinamide adenine dinucleotide (NAD, a key molecule for mitochondrial health) declines in an age-dependent manner. We hypothesized that this decline in NAD renders retinal ganglion cells susceptible to damage during periods of elevated intraocular pressure. To replete NAD levels in this glaucoma, we administered nicotinamide (the amide of vitamin B3). At the lowest dose tested, nicotinamide robustly protected from glaucoma (~70% of eyes had no detectable glaucomatous neurodegeneration). At this dose, nicotinamide had no influence on intraocular pressure and so its effect was neuroprotective. At the highest dose tested, 93% of eyes had no detectable glaucoma. This represents a ~10-fold decrease in the risk of developing glaucoma. At this dose, intraocular pressure still became elevated but there was a reduction in the degree of elevation showing an additional benefit. Thus, nicotinamide is unexpectedly potent at preventing this glaucoma and is an attractive option for glaucoma therapeutics. Our findings demonstrate the promise for both preventing and treating glaucoma by interventions that bolster metabolism during increasing age and during periods of elevated intraocular pressure. Nicotinamide prevents age-related declines in NAD (a decline that occurs in different genetic contexts and species). NAD precursors are reported to protect from a variety of neurodegenerative conditions. Thus, nicotinamide may provide a much needed neuroprotective treatment against human glaucoma. This manuscript summarizes human data implicating mitochondria in glaucoma, and argues for studies to

Cyclic mononucleotides modulate potassium and calcium flux responses to H2O2 in Arabidopsis roots

KAUST Repository

Ordoñ ez, Natalia Maria; Marondedze, Claudius; Thomas, Ludivine; Pasqualini, Stefania; Shabala, Lana; Shabala, Sergey; Gehring, Christoph A

2014-01-01

Cyclic mononucleotides are messengers in plant stress responses. Here we show that hydrogen peroxide (H2O2) induces rapid net K+-efflux and Ca2+-influx in Arabidopsis roots. Pre-treatment with either 10 μM cAMP or cGMP for 1 or 24 h does

Nicotinamide induces mitochondrial-mediated apoptosis through oxidative stress in human cervical cancer HeLa cells.

Science.gov (United States)

Feng, Yi; Wang, Yonghua; Jiang, Chengrui; Fang, Zishui; Zhang, Zhiqiang; Lin, Xiaoying; Sun, Liwei; Jiang, Weiying

2017-07-15

Nicotinamide participates in energy metabolism and influences cellular redox status and modulates multiple pathways related with both cellular survival and death. Recent studies have shown that it induced proliferation inhibition and apoptosis in many cancer cells. However, little is known about the effects of nicotinamide on human cervical cancer cells. We aimed to evaluate the effects of the indicated concentrations nicotinamide on cell proliferation, apoptosis and redox-related parameters in HeLa cells and investigated the apoptotic mechanism. After the treatment of the indicated concentrations nicotinamide, HeLa cell proliferation was evaluated by the CCK-8 assay and the production of ROS (reactive oxygen species) was measured using 2',7'-Dichlorofluorescin diacetate. The apoptotic effect was confirmed by observing the cellular and nuclear morphologies with fluorescence microscope and apoptotic rate of HeLa cell apoptosis was measured by flow cytometry using Annexin-V method. Moreover, we examined the mitochondrial membrane potential by JC-1 method and measured the expression of apoptosis related genes using qRT-PCR and immunoblotting. Nicotinamide restrained the HeLa cell proliferation and significantly increased the accumulation of ROS and depletion of GSH at relatively high concentrations. Furthermore, nicotinamide promoted HeLa cell apoptosis via the intrinsic mitochondrial apoptotic pathway. Our study revealed that nicotinamide induced the apoptosis through oxidative stress and intrinsic mitochondrial apoptotic pathways in HeLa cell. The results emerge that nicotinamide may be an inexpensive, safe and promising therapeutic agent or a neoadjuvant chemotherapy for cervical cancer patients, as well useful to find new drugs for cervical cancer therapy. Copyright © 2017 Elsevier Inc. All rights reserved.

NAD-content and metabolism in the mouse embryo and developing brain

International Nuclear Information System (INIS)

Beuningen, M. van; Streffer, C.; Beuningen, D. van

1986-01-01

Biochemical studies have shown that NAD is not only the coenzyme of dehydrogenase but also the substrate of poly-(ADPR)-synthetase which is involved in processes of cell proliferation and differentiation. The NAD and protein content was determined in the total embryo and in the CNS 9 to 13 days p.c. The embryos were X-irradiated 9 days p.c. The NAD content increased in the total mouse embryo during the early organogenesis. At the later period a decrease of the NAD content per mg protein was observed. This latter effect was apparently due to an increase of the NAD glycohydrolase activity. This enzyme degrades NAD. A similar development was observed in the developing mouse brain. However, the maximal NAD content per mg protein occurred on day 10 p.c. One of the enzyme activities, which are responsible for NAD synthesis, NMN-pyrophosphorylase, also increased in the brain at the same time. After the injection of C 14-nicotinamide, a precursor of NAD, it was observed that the radioactivity mainly appeared in nicotinamide and NAD. With progressing embryological development less nicotinamide was taken up by the embryonic tissue. When the embryos were X-irradiated on day 9 p.c. with 1.8 Gy the increase of NAD was considerably reduced during the next days, so that also the NAD level per mg protein was reduced. Also the NAD biosynthesis apparently decreased. This was shown again by the reduced NMN-pyrophosphorylase activity. The dose dependance of these effects was studied in the dose range 0.48-1.8 Gy. Two days p.r. most of the radiation effects were normalized again and at later periods even an overshoot of the enzyme activity was observed. The possible relevance of these effects for cell proliferation will be discussed. (orig.)

Concentrations of Nicotinamide in Plasma by RP-HPLC With Fluorescence Detection

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Pan Zhipeng

2016-01-01

Full Text Available The purpose of this study is to establish a new method for detecting nicotinamide concentration in plasma. In the experiment, the high performance liquid chromatography (HPLC method was used, with a fluorescence detector. The nicotinamide in the plasma was first converted to N1- methylnicotinamide, then reacted with acetophenone under certain conditions to produce fluorescent derivatives for testing. The method is a kind of highly sensitive detection, of which the lower limit is 10 ng/mL, the recovery rate is between 92.75% and 105.13%, and the relative standard deviation (RSD is between 3.76% and 4.43%. The results showed that this measurement method is accurate, sensitive and rapid. It meets the requirements of the experiment, and applies to the detection of nicotinamide concentration in plasma.

Cocrystal of Ibuprofen–Nicotinamide: Solid-State Characterization and In Vivo Analgesic Activity Evaluation

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Yori Yuliandra

2018-06-01

Full Text Available Ibuprofen is classified as a BCS class II drug which has low solubility and high permeability. We conducted the formation of the cocrystalline phase of ibuprofen with coformer nicotinamide to increase its solubility. The purpose of this study was to characterize the solid state of cocrystalline phase of ibuprofen-nicotinamide, determine the solubility, and evaluate its in vivo analgesic activity. The cocrystal of ibuprofen-nicotinamide was prepared by a slow evaporation method. The solid-state characterization was conducted by powder X-ray diffraction (PXRD analysis, differential thermal analysis (DTA, and scanning electron microscopy (SEM. To investigate the in vivo analgesic activity, 28 male Swiss-Webster mice were injected with acetic acid 0.5% following oral administration of intact ibuprofen, physical mixture, and its cocrystalline phase with nicotinamide (equivalent to 26 mg/kg ibuprofen. The number of writhes was counted, and pain inhibition was calculated. All data were analyzed with one-way ANOVA followed by Duncan’s Multiple Range Test (95% confidence interval. The results revealed that a new cocrystalline phase was successfully formed. The solubility testing showed that the cocrystal formation enhanced the solubility significantly as compared with the physical mixture and intact ibuprofen. A significant increase in the analgesic activity of cocrystal ibuprofen-nicotinamide was also confirmed.

Nicotinamide inhibits vasculogenic mimicry, an alternative vascularization pathway observed in highly aggressive melanoma.

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Orit Itzhaki

Full Text Available Vasculogenic mimicry (VM describes functional vascular channels composed only of tumor cells and its presence predicts poor prognosis in melanoma patients. Inhibition of this alternative vascularization pathway might be of clinical importance, especially as several anti-angiogenic therapies targeting endothelial cells are largely ineffective in melanoma. We show the presence of VM structures histologically in a series of human melanoma lesions and demonstrate that cell cultures derived from these lesions form tubes in 3D cultures ex vivo. We tested the ability of nicotinamide, the amide form of vitamin B3 (niacin, which acts as an epigenetic gene regulator through unique cellular pathways, to modify VM. Nicotinamide effectively inhibited the formation of VM structures and destroyed already formed ones, in a dose-dependent manner. Remarkably, VM formation capacity remained suppressed even one month after the complete withdrawal of Nicotimamid. The inhibitory effect of nicotinamide on VM formation could be at least partially explained by a nicotinamide-driven downregulation of vascular endothelial cadherin (VE-Cadherin, which is known to have a central role in VM. Further major changes in the expression profile of hundreds of genes, most of them clustered in biologically-relevant clusters, were observed. In addition, nicotinamide significantly inhibited melanoma cell proliferation, but had an opposite effect on their invasion capacity. Cell cycle analysis indicated moderate changes in apoptotic indices. Therefore, nicotinamide could be further used to unravel new biological mechanisms that drive VM and tumor progression. Targeting VM, especially in combination with anti-angiogenic strategies, is expected to be synergistic and might yield substantial anti neoplastic effects in a variety of malignancies.

Permeability of Rickettsia prowazekii to NAD

International Nuclear Information System (INIS)

Atkinson, W.H.; Winkler, H.H.

1989-01-01

Rickettsia prowazekii accumulated radioactivity from [adenine-2,8-3H]NAD but not from [nicotinamide-4-3H]NAD, which demonstrated that NAD was not taken up intact. Extracellular NAD was hydrolyzed by rickettsiae with the products of hydrolysis, nicotinamide mononucleotide and AMP, appearing in the incubation medium in a time- and temperature-dependent manner. The particulate (membrane) fraction contained 90% of this NAD pyrophosphatase activity. Rickettsiae which had accumulated radiolabel after incubation with [adenine-2,8-3H]NAD were extracted, and the intracellular composition was analyzed by chromatography. The cells contained labeled AMP, ADP, ATP, and NAD. The NAD-derived intracellular AMP was transported via a pathway distinct from and in addition to the previously described AMP translocase. Exogenous AMP (1 mM) inhibited uptake of radioactivity from [adenine-2,8-3H]NAD and hydrolysis of extracellular NAD. AMP increased the percentage of intracellular radiolabel present as NAD. Nicotinamide mononucleotide was not taken up by the rickettsiae, did not inhibit hydrolysis of extracellular NAD, and was not a good inhibitor of the uptake of radiolabel from [adenine-2,8-3H]NAD. Neither AMP nor ATP (both of which are transported) could support the synthesis of intracellular NAD. The presence of intracellular [adenine-2,8-3H]NAD within an organism in which intact NAD could not be transported suggested the resynthesis from AMP of [adenine-2,8-3H]NAD at the locus of NAD hydrolysis and translocation

Big Brains, Meat, Tuberculosis, and the Nicotinamide Switches: Co-Evolutionary Relationships with Modern Repercussions?

Directory of Open Access Journals (Sweden)

Adrian C. Williams

2013-01-01

Full Text Available Meat-eating was a game changer for human evolution. We suggest that the limiting factors for expanding brains earlier were scarcities of nicotinamide and tryptophan. In humans and some other omnivores, lack of meat causes these deficiencies. Nicotinamide adenine dinucleotide (NADH is necessary to synthesize adenosine triphosphate (ATP via either glycolysis or via the mitochondrial respiratory chain. NAD consumption is also necessary for developmental and repair circuits. Inadequate supplies result in “de-evolutionary” brain atrophy, as seen with pellagra. If trophic nicotinamide/tryptophan was a “prime mover” in building bigger brains, back-up mechanisms should have evolved. One strategy may be to recruit extra gut symbionts that produce NADH precursors or export nicotinamide (though this may cause diarrhea. We propose a novel supplier TB that co-evolved early, which did not originally and does not now inevitably cause disease. TB has highly paradoxical immunology for a pathogen, and secretes and is inhibited by nicotinamide and its analogue, isoniazid. Sharp declines in TB and diarrhea correlated with increased meat intake in the past, suggesting that dietary vitamin B 3 and tryptophan deficiencies (also associated with poor cognition and decreased lifespans are still common where meat is unaffordable.

A therapeutic benefit from combining normobaric carbogen or oxygen with nicotinamide in fractionated X-ray treatments

International Nuclear Information System (INIS)

Kjellen, E.; Joiner, M.C.; Collier, J.M.; Johns, H.; Rojas, A.

1991-01-01

The ability of normobaric oxygen and carbogen (95 percent O 2 + 5 percent CO 2 ) combined with nicotinamide to enhance the radiosensitivity of two rodent adenocarcinomas and of mouse skin and kidneys was compared with the effects of radiation in air and without the drug. A comparison of the results in tumors and normal tissues showed that significant therapeutic benefit was obtained with normobaric oxygen and carbogen combined with nicotinamide. Toxic side effects of the treatment are unlikely, as prolonged administration of nicotinamide is well tolerated in man. The combination of normobaric carbogen with nicotinamide could be an effective method of enhancing tumor radiosensitivity in clinical radiotherapy where hypoxia limits the outcome of treatment. (author). 45 refs.; 4 fig.; 4 tabs

New function for Escherichia coli xanthosine phophorylase (xapA): genetic and biochemical evidences on its participation in NAD+ salvage from nicotinamide

Science.gov (United States)

2014-01-01

Background In an effort to reconstitute the NAD+ synthetic pathway in Escherichia coli (E. coli), we produced a set of gene knockout mutants with deficiencies in previously well-defined NAD+de novo and salvage pathways. Unexpectedly, the mutant deficient in NAD+de novo and salvage pathway I could grow in M9/nicotinamide medium, which was contradictory to the proposed classic NAD+ metabolism of E. coli. Such E. coli mutagenesis assay suggested the presence of an undefined machinery to feed nicotinamide into the NAD+ biosynthesis. We wanted to verify whether xanthosine phophorylase (xapA) contributed to a new NAD+ salvage pathway from nicotinamide. Results Additional knockout of xapA further slowed down the bacterial growth in M9/nicotinamide medium, whereas the complementation of xapA restored the growth phenotype. To further validate the new function of xapA, we cloned and expressed E. coli xapA as a recombinant soluble protein. Biochemical assay confirmed that xapA was capable of using nicotinamide as a substrate for nicotinamide riboside formation. Conclusions Both the genetic and biochemical evidences indicated that xapA could convert nicotinamide to nicotinamide riboside in E. coli, albeit with relatively weak activity, indicating that xapA may contribute to a second NAD+ salvage pathway from nicotinamide. We speculate that this xapA-mediated NAD+ salvage pathway might be significant in some bacteria lacking NAD+de novo and NAD+ salvage pathway I or II, to not only use nicotinamide riboside, but also nicotinamide as precursors to synthesize NAD+. However, this speculation needs to be experimentally tested. PMID:24506841

N3 and O2 Protonated Conformers of the Cytosine Mononucleotides Coexist in the Gas Phase

Science.gov (United States)

Wu, R. R.; Hamlow, L. A.; He, C. C.; Nei, Y.-w.; Berden, G.; Oomens, J.; Rodgers, M. T.

2017-08-01

The gas-phase conformations of the protonated forms of the DNA and RNA cytosine mononucleotides, [pdCyd+H]+ and [pCyd+H]+, are examined by infrared multiple photon dissociation (IRMPD) action spectroscopy over the IR fingerprint and hydrogen-stretching regions complemented by electronic structure calculations. The low-energy conformations of [pdCyd+H]+ and [pCyd+H]+ and their relative stabilities are computed at the B3LYP/6-311+G(2d,2p)//B3LYP/6-311+G(d,p) and MP2(full)/6-311+G(2d,2p)//B3LYP/6-311+G(d,p) levels of theory. Comparisons of the measured IRMPD action spectra and B3LYP/6-311+G(d,p) linear IR spectra computed for the low-energy conformers allow the conformers present in the experiments to be determined. Similar to that found in previous IRMPD action spectroscopy studies of the protonated forms of the cytosine nucleosides, [dCyd+H]+ and [Cyd+H]+, both N3 and O2 protonated cytosine mononucleotides exhibiting an anti orientation of cytosine are found to coexist in the experimental population. The 2'-hydroxyl substituent does not significantly influence the most stable conformations of [pCyd+H]+ versus those of [pdCyd+H]+, as the IRMPD spectral profiles of [pdCyd+H]+ and [pCyd+H]+ are similar. However, the presence of the 2'-hydroxyl substituent does influence the relative intensities of the measured IRMPD bands. Comparisons to IRMPD spectroscopy studies of the deprotonated forms of the cytosine mononucleotides, [pdCyd-H]- and [pCyd-H]-, provide insight into the effects of protonation versus deprotonation on the conformational features of the nucleobase and sugar moieties. Likewise, comparisons to results of IRMPD spectroscopy studies of the protonated cytosine nucleosides provide insight into the influence of the phosphate moiety on structure. Comparison with previous ion mobility results shows the superiority of IRMPD spectroscopy for distinguishing various protonation sites.

Nicotinamide and PNC1 govern lifespan extension by calorie restriction in Saccharomyces cerevisiae.

Science.gov (United States)

Anderson, Rozalyn M; Bitterman, Kevin J; Wood, Jason G; Medvedik, Oliver; Sinclair, David A

2003-05-08

Calorie restriction extends lifespan in a broad range of organisms, from yeasts to mammals. Numerous hypotheses have been proposed to explain this phenomenon, including decreased oxidative damage and altered energy metabolism. In Saccharomyces cerevisiae, lifespan extension by calorie restriction requires the NAD+-dependent histone deacetylase, Sir2 (ref. 1). We have recently shown that Sir2 and its closest human homologue SIRT1, a p53 deacetylase, are strongly inhibited by the vitamin B3 precursor nicotinamide. Here we show that increased expression of PNC1 (pyrazinamidase/nicotinamidase 1), which encodes an enzyme that deaminates nicotinamide, is both necessary and sufficient for lifespan extension by calorie restriction and low-intensity stress. We also identify PNC1 as a longevity gene that is responsive to all stimuli that extend lifespan. We provide evidence that nicotinamide depletion is sufficient to activate Sir2 and that this is the mechanism by which PNC1 regulates longevity. We conclude that yeast lifespan extension by calorie restriction is the consequence of an active cellular response to a low-intensity stress and speculate that nicotinamide might regulate critical cellular processes in higher organisms.

Radiosensitization effects of nicotinamide on malignant and normal mouse tissue

International Nuclear Information System (INIS)

Jonsson, G.G.; Kjellen, E.; Pero, R.W.; Cameron, R.

1985-01-01

Inhibitors of the chromatin-associated enzyme adenosine diphosphate ribosyltransferase have been found to inhibit DNA strand rejoining and to potentiate lethality of DNA-damaging agents both in vivo and in vitro. The authors have in this work examined the radiosensitizing potential of one such inhibitor, nicotinamide, on tumor tissue by using transplanted C3H mouse mammary adenocarcinomas and on normal tissue in a tail-stunting experiment using BALB/cA mice. The data indicate a radiosensitizing effect of nicotinamide on tumor cells as well as on normal tissue. The data indicate a possible role of adenosine diphosphate ribosyltransferase inhibitors as a sensitizing agent in the radiotherapy of malignant tumors

Simvastatin-nicotinamide co-crystal: design, preparation and ...

African Journals Online (AJOL)

Purpose: To improve the solubility of simvastatin (SV) by co-crystallization using nicotinamide (Nic) as co-crystal agent (co-former). Methods: In silico molecular modeling of Nic counter to SV were investigated using Auto Dock 4.2. Cocrystal of Nic-SV was obtained by solvent evaporation (SE) using an equimolar ratio of Nic ...

Different effects of histone deacetylase inhibitors nicotinamide and trichostatin A (TSA) in C17.2 neural stem cells.

Science.gov (United States)

Wang, Haifeng; Cheng, Hua; Wang, Kai; Wen, Tieqiao

2012-11-01

Histone deacetylase inhibitors are involved in proliferation, apoptosis, cell cycle, mRNA transcription, and protein expression in various cells. However, the molecular mechanism underlying such functions is still not fully clear. In this study, we used C17.2 neural stem cell (NSC) line as a model to evaluate the effects of nicotinamide and trichostatin A (TSA) on cell characteristics. Results show that nicotinamide and TSA greatly inhibit cell growth, lead to cell morphology changes, and effectively induce cell apoptosis in a dose-dependent manner. Western blot analyses confirmed that nicotinamide significantly decreases the expression of bcl-2 and p38. Further insight into the molecular mechanisms shows the suppression of phosphorylation in eukaryotic initiation factor 4E-binding protein 1 (4EBP1) by nicotinamide, whereas, an increased expression of bcl-2 and p38 and phosphorylation of 4EBP1 by TSA. However, both nicotinamide and TSA significantly increase the expression of cytochrome c (cyt c). These results strongly suggest that bcl-2, p38, cyt c, and p-4EBP1 could suppress proliferation and induce apoptosis of C17.2 NSCs mediated by histone deacetylase inhibitors, nicotinamide and TSA, involving different molecular mechanisms.

21 CFR 172.315 - Nicotinamide-ascorbic acid complex.

Science.gov (United States)

2010-04-01

... 172.315 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.315 Nicotinamide-ascorbic acid complex...

Photo-induced reduction of flavin mononucleotide in aqueous solutions

International Nuclear Information System (INIS)

Song, S.-H.; Dick, B.; Penzkofer, A.

2007-01-01

The photo-induced reduction of flavin mononucleotide (FMN) in aqueous solutions is studied by absorption spectra measurement under aerobic and anaerobic conditions. Samples without exogenous reducing agent and with the exogenous reducing agents ethylene-diamine-tetraacetic acid (EDTA) and dithiothreitol (DTT) are investigated. Under anaerobic conditions the photo-induced reduction with and without reducing agents is irreversible. Under aerobic conditions the photo-reduction without added reducing agent is small compared to the photo-degradation, and the photo-reduction of FMN by the reducing agents is reversible (re-oxidation in the dark). During photo-excitation of FMN the dissolved oxygen is consumed by singlet oxygen formation and subsequent chemical reaction. After light switch-off slow re-oxidation (slow absorption recovery) occurs due to air in-diffusion from surface. EDTA degradation by FMN excitation leads to oxygen scavenging. The quantum efficiencies of photo-reduction under aerobic and anaerobic conditions are determined. The re-oxidation of reduced FMN under aerobic conditions and due to air injection is investigated

Nicotinamidase participates in the salvage pathway of NAD biosynthesis in Arabidopsis.

Science.gov (United States)

Wang, Guodong; Pichersky, Eran

2007-03-01

Nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP), which is derived from NAD, have important roles as a redox carriers in metabolism. A combination of de novo and salvage pathways contribute to the biosynthesis of NAD in all organisms. The pathways and enzymes of the NAD salvage pathway in yeast and animals, which diverge at nicotinamide, have been extensively studied. Yeast cells convert nicotinamide to nicotinic acid, while mammals lack the enzyme nicotinamidase and instead convert nicotinamide to nicotinamide mononucleotide. Here we show that Arabidopsis thaliana gene At2g22570 encodes a nicotinamidase, which is expressed in all tissues, with the highest levels observed in roots and stems. The 244-residue protein, designated AtNIC1, converts nicotinamide to nicotinic acid and has a Km value of 118 +/- 17 microM and a Kcat value of 0.93 +/- 0.13 sec(-1). Plants homozygous for a null AtNIC1 allele, nic1-1, have lower levels of NAD and NADP under normal growth conditions, indicating that AtNIC1 participates in a yeast-type NAD salvage pathway. Mutant plants also exhibit hypersensitivity to treatments of abscisic acid and NaCl, which is correlated with their inability to increase the cellular levels of NAD(H) under these growth conditions, as occurs in wild-type plants. We also show that the growth of the roots of wild-type but not nic1-1 mutant plants is inhibited and distorted by nicotinamide.

Pathways and Subcellular Compartmentation of NAD Biosynthesis in Human Cells

Science.gov (United States)

Nikiforov, Andrey; Dölle, Christian; Niere, Marc; Ziegler, Mathias

2011-01-01

NAD is a vital redox carrier, and its degradation is a key element of important regulatory pathways. NAD-mediated functions are compartmentalized and have to be fueled by specific biosynthetic routes. However, little is known about the different pathways, their subcellular distribution, and regulation in human cells. In particular, the route(s) to generate mitochondrial NAD, the largest subcellular pool, is still unknown. To visualize organellar NAD changes in cells, we targeted poly(ADP-ribose) polymerase activity into the mitochondrial matrix. This activity synthesized immunodetectable poly(ADP-ribose) depending on mitochondrial NAD availability. Based on this novel detector system, detailed subcellular enzyme localizations, and pharmacological inhibitors, we identified extracellular NAD precursors, their cytosolic conversions, and the pathway of mitochondrial NAD generation. Our results demonstrate that, besides nicotinamide and nicotinic acid, only the corresponding nucleosides readily enter the cells. Nucleotides (e.g. NAD and NMN) undergo extracellular degradation resulting in the formation of permeable precursors. These precursors can all be converted to cytosolic and mitochondrial NAD. For mitochondrial NAD synthesis, precursors are converted to NMN in the cytosol. When taken up into the organelles, NMN (together with ATP) serves as substrate of NMNAT3 to form NAD. NMNAT3 was conclusively localized to the mitochondrial matrix and is the only known enzyme of NAD synthesis residing within these organelles. We thus present a comprehensive dissection of mammalian NAD biosynthesis, the groundwork to understand regulation of NAD-mediated processes, and the organismal homeostasis of this fundamental molecule. PMID:21504897

A Rapid and Efficient Assay for the Characterization of Substrates and Inhibitors of Nicotinamide N-Methyltransferase

NARCIS (Netherlands)

van Haren, Matthijs J; Sastre Torano, Javier; Sartini, Davide; Emanuelli, Monica; Parsons, Richard B; Martin, Nathaniel I

2016-01-01

Nicotinamide N-methyltransferase (NNMT) is one of the most abundant small molecule methyltransferases in the human body and is primarily responsible for the N-methylation of the nicotinamide (vitamin B3). Employing the cofactor S-adenosyl-l-methionine, NNMT transfers a methyl group to the pyridine

[The influence of fasting, of a hyperprotein diet and of nicotinamide on hepatic L-threonine deaminase].

Science.gov (United States)

Aleo, M F; Casella, A; Marinello, E

1981-09-15

The induction of L-threonine deaminase, following nicotinamide injection has been studied: the effect of fasting and of hyperproteic diet have been also taken in consideration. Maximal induction is observed after 5 days hyperproteic diet, and is additional only with nicotinamide treatment. Results are interpreted assuming a different hepatic content and behavior of multiple forms of the enzyme.

Phosphoribosylpyrophosphate (PRPP)-less mutants of Escherichia coli

DEFF Research Database (Denmark)

Hove-Jensen, Bjarne

1989-01-01

A DNA fragment encoding kanamycin resistance was inserted in vitro into a plasmid-borne prs gene encoding phosphoribosylpyrophosphate synthetase of Escherichia coli. The resulting plasmids were subsequently transferred to the chromosome by homologous recombination and the haploid strains prs-3::Kan......R and prs-4::KanR were obtained. These strains were fully viable, but required guanosine, uridine, histidine, tryptophan and nicotinamide mononucleotide. There was no phosphoribosylpyrophosphate synthetase activity or phosphoribosylpyrophosphate pool in the mutant strains. These results show...

A two year observational study of nicotinamide and intensive insulin therapy in patients with recent onset type 1 diabetes mellitus.

Science.gov (United States)

Crinó, A; Schiaffini, R; Ciampalini, P; Suraci, M C; Manfrini, S; Visalli, N; Matteoli, M C; Patera, P; Buzzetti, R; Guglielmi, C; Spera, S; Costanza, F; Fioriti, E; Pitocco, D; Pozzilli, P

2005-08-01

A number of trials have evaluated residual beta-cell function in patients with recent onset type 1 diabetes mellitus (DM1) treated with nicotinamide in addition to intensive insulin therapy (IIT). In most studies, only a slight decline of C-peptide secretion was observed 12 months after diagnosis; however, no data is available on C-peptide secretion and metabolic control in patients continuing nicotinamide and IIT for up to 2 years after diagnosis. We retrospectively analysed data from 25 patients (mean age 14.7 years +/- 5 SD) with DM1 in whom nicotinamide at a dose of 25 mg/kg b. wt. was added from diagnosis (< 4 weeks) to IIT (three injections of regular insulin at meals + one NPH at bed time) and continued for up to 2 years after diagnosis. Data were also analysed from patients (n = 27) in whom IIT was introduced at diagnosis and who were similarly followed for 2 years. Baseline C-peptide as well as insulin dose and HbA1c levels were evaluated at 12 and 24 months after diagnosis. In the course of the follow-up, patients on nicotinamide + IIT or IIT alone did not significantly differ in terms of C-peptide secretion (values at 24 months in the two groups were 0.19 +/- 0.24 nM vs 0.19 +/- 0.13 nM, respectively). Insulin requirement (0.6 +/- 0.3 U/kg/day vs 0.7 +/- 0.2 U/kg/day at 24 months, respectively) did not differ between the two groups. However, HbA1c was significantly lower 2 years after diagnosis in patients treated with nicotinamide + IIT (6.09 +/- 0.9% vs 6.98 +/- 0.9%, respectively, p < 0.01). No adverse effects were observed in patients receiving nicotinamide for 2 years. Implementation of IIT with the addition of nicotinamide at diagnosis continued for 2 years improves metabolic control as assessed by HbA1c. In both nicotinamide and control patients, no decline in C-peptide was detected 2 years after diagnosis, indicating that IIT preserves C-peptide secretion. We conclude that nicotinamide + IIT at diagnosis of DM1 prolonged for up to 2 years can be

Effects of radiosensitising agent nicotinamide on relative tissue perfusion and kidney junction in C3H mice

International Nuclear Information System (INIS)

Honess, D.J.; Bleehen, N.M.

1993-01-01

Nicotinamide is an effective radiosensitiser of murine tumours, functioning by improving tumour perfusion by decreasing the proportion of intermittently closed capillaries. The effect of nicotinamide on relative tissue perfusion of RIF-1 tumour and normal skin, muscle, lung, liver, kidney and spleen were investigated using the 86 Rb extraction technique. A dose of 1000 mg/kg was shown to have transient effects on tumour, skin and lung perfusion but to have sustained effects on muscle (a drop to 80% of control), liver, kidney and spleen (with increased ranging from 165% to 280% of control) from 0.5 to 4 h after treatment i.e. during the period of maximum radiosensitisation. These increases were evident at doses as low as 100 mg/kg. The data suggest that the radiosensitisation induced by nicotinamide in the mouse may be associated with these perfusion changes. Nicotinamide was also shown to have a substantial inhibitory effect on renal function, inhibiting 51 CrEDTA clearance by a factor (± 2 SE) of 2.56 ± 0.19 and 125 I-iodohippurate clearance by a factor of 2.07 ± 0.45 at 1000 mg/kg. These effects were shown to be dose-related, and to be evident at doses from 400 mg/kg upwards. This suggests that nicotinamide potentiation of co-administered cytotoxic agents may be mediated by reduced renal clearance of the cytotoxic drug, thus increasing the plasma half-life. (author)

Validation of diffuse correlation spectroscopy sensitivity to nicotinamide-induced blood flow elevation in the murine hindlimb using the fluorescent microsphere technique

Science.gov (United States)

Proctor, Ashley R.; Ramirez, Gabriel A.; Han, Songfeng; Liu, Ziping; Bubel, Tracy M.; Choe, Regine

2018-03-01

Nicotinamide has been shown to affect blood flow in both tumor and normal tissues, including skeletal muscle. Intraperitoneal injection of nicotinamide was used as a simple intervention to test the sensitivity of noninvasive diffuse correlation spectroscopy (DCS) to changes in blood flow in the murine left quadriceps femoris skeletal muscle. DCS was then compared with the gold-standard fluorescent microsphere (FM) technique for validation. The nicotinamide dose-response experiment showed that relative blood flow measured by DCS increased following treatment with 500- and 1000-mg / kg nicotinamide. The DCS and FM technique comparison showed that blood flow index measured by DCS was correlated with FM counts quantified by image analysis. The results of this study show that DCS is sensitive to nicotinamide-induced blood flow elevation in the murine left quadriceps femoris. Additionally, the results of the comparison were consistent with similar studies in higher-order animal models, suggesting that mouse models can be effectively employed to investigate the utility of DCS for various blood flow measurement applications.

Metabolomics analysis of metabolic effects of nicotinamide phosphoribosyltransferase (NAMPT inhibition on human cancer cells.

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Vladimir Tolstikov

Full Text Available Nicotinamide phosphoribosyltransferase (NAMPT plays an important role in cellular bioenergetics. It is responsible for converting nicotinamide to nicotinamide adenine dinucleotide, an essential molecule in cellular metabolism. NAMPT has been extensively studied over the past decade due to its role as a key regulator of nicotinamide adenine dinucleotide-consuming enzymes. NAMPT is also known as a potential target for therapeutic intervention due to its involvement in disease. In the current study, we used a global mass spectrometry-based metabolomic approach to investigate the effects of FK866, a small molecule inhibitor of NAMPT currently in clinical trials, on metabolic perturbations in human cancer cells. We treated A2780 (ovarian cancer and HCT-116 (colorectal cancer cell lines with FK866 in the presence and absence of nicotinic acid. Significant changes were observed in the amino acids metabolism and the purine and pyrimidine metabolism. We also observed metabolic alterations in glycolysis, the citric acid cycle (TCA, and the pentose phosphate pathway. To expand the range of the detected polar metabolites and improve data confidence, we applied a global metabolomics profiling platform by using both non-targeted and targeted hydrophilic (HILIC-LC-MS and GC-MS analysis. We used Ingenuity Knowledge Base to facilitate the projection of metabolomics data onto metabolic pathways. Several metabolic pathways showed differential responses to FK866 based on several matches to the list of annotated metabolites. This study suggests that global metabolomics can be a useful tool in pharmacological studies of the mechanism of action of drugs at a cellular level.

Clinical study of 89Sr therapy with radiosensitization by nicotinamide and carbogen in multiple bone metastasis of malignant neoplasms

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Liu Yajie; Wang Shubin; Guo Yiling; Chen Zuowei; Zhang Yingnan

2005-01-01

Objective: To evaluate the curative effect and side effects of 89 Sr therapy with radiosensitization by nicotinamide and carbogen in multiple bone metastasis of malignant neoplasms. Methods: Ninety-seven patients were divided into 4 groups respectively: group A, 89 Sr + nicotinamide + carbogen (24 patients); group B, 89 Sr + nicotinamide(22 patients); group C, 89 Sr + carbogen (25 patients); group D, 89 Sr, (26 patients). 89 SrCl was intravenously injected at a dose of 1.48-2.22 MBq/kg. Nicotinamide was taken orally 1 hour before 89 SrCl injection, 6 g/day, tid, d1-d5. Aspiration of carbogen(95%O 2 + 5%CO 2 ) gases, 6 L/min, 10 minutes, qd, d1-d5. Results: The effective rate of pain control and QOL improvement in A group were higher than in groups B, C and D (91.7% VS 77.3%, 76.0% and 69.2%, P=0.048). The lesions assessed by SPECT imaging in every group was not significantly different at three months after treatment. I to II degree toxic effect on bone marrow appeared in every group and there were no significantly inter-group differences. Conclusions: Combinative therapy using 89 Sr + nicotinamide + carbogen is more effective to treat multiple metastatic bone pain and for improvement of QOL. The side effects are not increased. (authors)

Nicotinamide and other benzamide analogs as agents for overcoming hypoxic cell radiation resistance in tumours

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Horsman, M.

1996-01-01

Oxygen deficient hypoxic cells, which are resistant to sparsely ionising radiation, have now been identified in most animal and some human solid tumours and will influence the response of those tumours to radiation treatment. This hypoxia can be either chronic, arising from an oxygen diffusion limitation, or acute, resulting from transient stoppages in microregional blood flow. Extensive experimental studies, especially in the last decade, have shown that nicotinamide and structurally related analogs can effectively sensitize murine tumours to both single and fractionated radiation treatments and that they do so in preference to the effects seen in mouse normal tissues. The earliest studies suggested that this enhancement of radiation damage was the result of an inhibition of the repair mechanisms. However, recent studies in mouse tumours have shown that these drugs prevent transient cessations in blood flow, thus inhibiting the development of acute hypoxia. This novel discovery led to the suggestion that the potential role of these agents as radiosensitizers would be when combined with treatments that overcame chronic hypoxia. The combined nicotinamide with hyperthermia proved that the enhancement of radiation damage by both agents together was greater than that seen with each agent alone. Similar results were later seen for nicotinamide combined with a perfluorochemical emulsion, carbogen breathing, and pentoxifylline, and in all these studies the effects in tumours were always greater than those seen in appropriate normal tissues. Of all the analogs, it is nicotinamide itself which has been the most extensively studied as a radiosensitizer in vivo and the one that shows the greatest effect in animal tumours. It is also an agent that has been well established clinically, with daily doses of up to 6 g, associated with a low incidence of side effects. This human dose is equivalent to 100-200 mg/kg in mice and such doses will maximally sensitize murine tumours to

NAD-Dependent DNA-Binding Activity of the Bifunctional NadR Regulator of Salmonella typhimurium

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Penfound, Thomas; Foster, John W.

1999-01-01

NadR is a 45-kDa bifunctional regulator protein. In vivo genetic studies indicate that NadR represses three genes involved in the biosynthesis of NAD. It also participates with an integral membrane protein (PnuC) in the import of nicotinamide mononucleotide, an NAD precursor. NadR was overexpressed and purified as a His-tagged fusion in order to study its DNA-binding properties. The protein bound to DNA fragments containing NAD box consensus sequences. NAD proved to be the relevant in vivo co...

Analytical Method Validation and Determination of Pyridoxine, Nicotinamide, and Caffeine in Energy Drinks Using Thin Layer Chromatography-Densitometry

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Florentinus Dika Octa Riswanto

2015-03-01

Full Text Available Food supplement which contains vitamins and stimulants such as caffeine were classified as energy drink. TLC-densitometry method was chosen to determine the pyridoxine, nicotinamide, and caffeine in the energy drink sample. TLC plates of silica gel 60 F254 was used as the stationary phase and methanol : ethyl acetate : ammonia 25% (134:77:10 was used as the mobile phase. The correlation coefficient for each pyridoxine, nicotinamide, and caffeine were 0.9982, 0.9997, and 0.9966, respectively. Detection and quantitation limits of from the three analytes were 4.05 and 13.51 µg/mL; 13.15 and 43.83 µg/mL; 5.43 and 18.11 µg/mL, respectively. The recovery of pyridoxine, nicotinamide, and caffeine were within the required limit range of 95-105%. The percent of RSD were below the limit value of 5.7% for caffeine and nicotinamide and 8% for pyridoxine. The content amount of pyridoxine in the sample 1 and 2 were 33.59 ± 0.981 and 30.29 ± 2.061 µg/mL, respectively. The content amount of nicotinamide in the sample 1 and 2 were 106.53 ± 3.521 and 98.20 ± 3.648 µg/mL, respectively. The content amount of caffeine in the sample 1 and 2 were 249.50 ± 5.080 and 252.80 ± 2.640 µg/mL, respectively. Robustness test results showed that the most optimal method conditions should be applied for the analysis.

Enhancing NAD+ Salvage Pathway Reverts the Toxicity of Primary Astrocytes Expressing Amyotrophic Lateral Sclerosis-linked Mutant Superoxide Dismutase 1 (SOD1)*

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Harlan, Benjamin A.; Pehar, Mariana; Sharma, Deep R.; Beeson, Gyda; Beeson, Craig C.; Vargas, Marcelo R.

2016-01-01

Nicotinamide adenine dinucleotide (NAD+) participates in redox reactions and NAD+-dependent signaling pathways. Although the redox reactions are critical for efficient mitochondrial metabolism, they are not accompanied by any net consumption of the nucleotide. On the contrary, NAD+-dependent signaling processes lead to its degradation. Three distinct families of enzymes consume NAD+ as substrate: poly(ADP-ribose) polymerases, ADP-ribosyl cyclases (CD38 and CD157), and sirtuins (SIRT1–7). Because all of the above enzymes generate nicotinamide as a byproduct, mammalian cells have evolved an NAD+ salvage pathway capable of resynthesizing NAD+ from nicotinamide. Overexpression of the rate-limiting enzyme in this pathway, nicotinamide phosphoribosyltransferase, increases total and mitochondrial NAD+ levels in astrocytes. Moreover, targeting nicotinamide phosphoribosyltransferase to the mitochondria also enhances NAD+ salvage pathway in astrocytes. Supplementation with the NAD+ precursors nicotinamide mononucleotide and nicotinamide riboside also increases NAD+ levels in astrocytes. Amyotrophic lateral sclerosis (ALS) is caused by the progressive degeneration of motor neurons in the spinal cord, brain stem, and motor cortex. Superoxide dismutase 1 (SOD1) mutations account for up to 20% of familial ALS and 1–2% of apparently sporadic ALS cases. Primary astrocytes isolated from mutant human superoxide dismutase 1-overexpressing mice as well as human post-mortem ALS spinal cord-derived astrocytes induce motor neuron death in co-culture. Increasing total and mitochondrial NAD+ content in ALS astrocytes increases oxidative stress resistance and reverts their toxicity toward co-cultured motor neurons. Taken together, our results suggest that enhancing the NAD+ salvage pathway in astrocytes could be a potential therapeutic target to prevent astrocyte-mediated motor neuron death in ALS. PMID:27002158

Synthesizing and salvaging NAD: lessons learned from Chlamydomonas reinhardtii.

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Huawen Lin

2010-09-01

Full Text Available The essential coenzyme nicotinamide adenine dinucleotide (NAD+ plays important roles in metabolic reactions and cell regulation in all organisms. Bacteria, fungi, plants, and animals use different pathways to synthesize NAD+. Our molecular and genetic data demonstrate that in the unicellular green alga Chlamydomonas NAD+ is synthesized from aspartate (de novo synthesis, as in plants, or nicotinamide, as in mammals (salvage synthesis. The de novo pathway requires five different enzymes: L-aspartate oxidase (ASO, quinolinate synthetase (QS, quinolate phosphoribosyltransferase (QPT, nicotinate/nicotinamide mononucleotide adenylyltransferase (NMNAT, and NAD+ synthetase (NS. Sequence similarity searches, gene isolation and sequencing of mutant loci indicate that mutations in each enzyme result in a nicotinamide-requiring mutant phenotype in the previously isolated nic mutants. We rescued the mutant phenotype by the introduction of BAC DNA (nic2-1 and nic13-1 or plasmids with cloned genes (nic1-1 and nic15-1 into the mutants. NMNAT, which is also in the de novo pathway, and nicotinamide phosphoribosyltransferase (NAMPT constitute the nicotinamide-dependent salvage pathway. A mutation in NAMPT (npt1-1 has no obvious growth defect and is not nicotinamide-dependent. However, double mutant strains with the npt1-1 mutation and any of the nic mutations are inviable. When the de novo pathway is inactive, the salvage pathway is essential to Chlamydomonas for the synthesis of NAD+. A homolog of the human SIRT6-like gene, SRT2, is upregulated in the NS mutant, which shows a longer vegetative life span than wild-type cells. Our results suggest that Chlamydomonas is an excellent model system to study NAD+ metabolism and cell longevity.

Congenital malformations in embryos of female mice exposed to alcohol and nicotinamide

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Natasha Soares Simões dos Santos

2009-03-01

Full Text Available Objective: To compare the incidence of congenital malformations among the offspring of female mice exposed to alcohol or alcohol plus nicotinamide. Methods: Three groups of pregnant C57BL/6J mice were studied; G1 received alcohol (5 g/kg in saline solution (20% - vol/vol; G2 received nicotinamide, 50 mg/ml associated to alcohol; and G3, only saline solution; all by intraperitoneal injection on the seventh day of pregnancy. The animals were killed in a CO2 chamber on day 18 of pregnancy. The intrauterine content was assessed and the number of complete and reabsorbed fetuses was counted. The complete fetuses had their weight and crown-rump length measured and malformations were identified. Rresults: G1 showed the highest number of malformations: micrognathia, low set ears, hypertrophic nose, scoliosis, and atrophy of the lower and upper limbs. Weight was significantly different among the groups (p = 0.0139, and in G1 it was below average as compared to G3 (p = 0.3133. As for length, the lowest values were found in G2 and G3 showed the highest ones. There was a significant difference among the groups (p = 0.0145. Cconclusions: Ethanol, when administered to pregnant mice was teratogenic. However, length of G1 fetuses was, in average, higher than that of other groups. Nicotinamide decreased the number of malformations and may be a possible protector against alcohol effects.

Maternal intake of fat, riboflavin and nicotinamide and the risk of having offspring with congenital heart defects.

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Smedts, Huberdina P M; Rakhshandehroo, Maryam; Verkleij-Hagoort, Anna C; de Vries, Jeanne H M; Ottenkamp, Jaap; Steegers, Eric A P; Steegers-Theunissen, Régine P M

2008-10-01

With the exception of studies on folic acid, little evidence is available concerning other nutrients in the pathogenesis of congenital heart defects (CHDs). Fatty acids play a central role in embryonic development, and the B-vitamins riboflavin and nicotinamide are co-enzymes in lipid metabolism. To investigate associations between the maternal dietary intake of fats, riboflavin and nicotinamide, and CHD risk in the offspring. A case-control family study was conducted in 276 mothers of a child with a CHD comprising of 190 outflow tract defects (OTD) and 86 non-outflow tract defects (non-OTD) and 324 control mothers of a non-malformed child. Mothers filled out general and food frequency questionnaires at 16 months after the index-pregnancy, as a proxy of the habitual food intake in the preconception period. Nutrient intakes (medians) were compared between cases and controls by Mann-Whitney U test. Odds ratios (OR) for the association between CHDs and nutrient intakes were estimated in a logistic regression model. Case mothers, in particular mothers of a child with OTD, had higher dietary intakes of saturated fat, 30.9 vs. 29.8 g/d; P riboflavin and nicotinamide were lower in mothers of a child with an OTD than in controls (1.32 vs. 1.41 mg/d; P riboflavin (riboflavin and nicotinamide seems to contribute to CHD risk, in particular OTDs.

Stability characteristics and structural properties of single- and double-walled boron-nitride nanotubes under physical adsorption of Flavin mononucleotide (FMN) in aqueous environment using molecular dynamics simulations

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Ansari, R.; Ajori, S.; Ameri, A.

2016-01-01

Graphical abstract: Structural properties and stability characteristics of single- and double-walled boron-nitride nanotubes functionalized with Flavin mononucleotide (FMN) in aqueous environment are investigated employing molecular dynamics simulations. - Highlights: • Structural and buckling analysis of boron-nitride nanotubes under physical adsorption of Flavin mononucleotide (FMN). • Gyration radius increases linearly as the weight percentage of FMN increases. • Presence of water molecules results in more expansion of FMN around BNNTs. • Critical buckling force of functionalized BNNTs is higher than that of pure BNNTs. • The critical strain of functionalized BNNTs is found to be lower than that of pure ones. - Abstract: The non-cytotoxic properties of Boron-nitride nanotubes (BNNTs) and the ability of stable interaction with biomolecules make them so promising for biological applications. In this research, molecular dynamics (MD) simulations are performed to investigate the structural properties and stability characteristics of single- and double-walled BNNTs under physical adsorption of Flavin mononucleotide (FMN) in vacuum and aqueous environments. According to the simulation results, gyration radius increases by rising the weight percentage of FMN. Also, the results demonstrate that critical buckling force of functionalized BNNTs increases in vacuum. Moreover, it is observed that by increasing the weight percentage of FMN, critical force of functionalized BNNTs rises. By contrast, critical strain reduces by functionalization of BNNTs in vacuum. Considering the aqueous environment, it is observed that gyration radius and critical buckling force of functionalized BNNTs increase more considerably than those of functionalized BNNTs in vacuum, whereas the critical strains approximately remain unchanged.

Generation of 1:1 Carbamazepine:Nicotinamide cocrystals by spray drying.

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Patil, Shashank P; Modi, Sameer R; Bansal, Arvind K

2014-10-01

The present study investigates the potential of spray drying as a technique for generation of pharmaceutical cocrystals. Carbamazepine-Nicotinamide cocrystal (CNC) was chosen as model cocrystal system for this study. Firstly, CNC was generated using liquid assisted grinding and used for generation of phase solubility diagram (PSD) and ternary phase diagram (TPD). Both PSD and TPD were carefully evaluated for phase behavior of CNC when equilibrated with solvent. The undersaturated region with respect to CNC, as depicted by TPD, was selected as target region to initiate cocrystallization experiments. Various points in this region, representative of different compositions of Carbamazepine, Nicotinamide and CNC, were selected and spray drying was carried out. The spray dried product was characterized for solid state properties and was compared with CNC generated by liquid assisted grinding. Spray drying successfully generated CNC of similar quality as those generated by liquid assisted grinding. Moreover, there was no significant impact of process variables on formation of CNC. Spray drying, owing to its simplicity and industrial scalability, can be a promising method for large scale cocrystal generation. Copyright © 2014 Elsevier B.V. All rights reserved.

Nicotinamide enhances repair of arsenic and ultraviolet radiation-induced DNA damage in HaCaT keratinocytes and ex vivo human skin.

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Benjamin C Thompson

Full Text Available Arsenic-induced skin cancer is a significant global health burden. In areas with arsenic contamination of water sources, such as China, Pakistan, Myanmar, Cambodia and especially Bangladesh and West Bengal, large populations are at risk of arsenic-induced skin cancer. Arsenic acts as a co-carcinogen with ultraviolet (UV radiation and affects DNA damage and repair. Nicotinamide (vitamin B3 reduces premalignant keratoses in sun-damaged skin, likely by prevention of UV-induced cellular energy depletion and enhancement of DNA repair. We investigated whether nicotinamide modifies DNA repair following exposure to UV radiation and sodium arsenite. HaCaT keratinocytes and ex vivo human skin were exposed to 2μM sodium arsenite and low dose (2J/cm2 solar-simulated UV, with and without nicotinamide supplementation. DNA photolesions in the form of 8-oxo-7,8-dihydro-2'-deoxyguanosine and cyclobutane pyrimidine dimers were detected by immunofluorescence. Arsenic exposure significantly increased levels of 8-oxo-7,8-dihydro-2'-deoxyguanosine in irradiated cells. Nicotinamide reduced both types of photolesions in HaCaT keratinocytes and in ex vivo human skin, likely by enhancing DNA repair. These results demonstrate a reduction of two different photolesions over time in two different models in UV and arsenic exposed cells. Nicotinamide is a nontoxic, inexpensive agent with potential for chemoprevention of arsenic induced skin cancer.

Cleavage of nicotinamide adenine dinucleotide by the ribosome-inactivating protein from Momordica charantia.

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Vinkovic, M; Dunn, G; Wood, G E; Husain, J; Wood, S P; Gill, R

2015-09-01

The interaction of momordin, a type 1 ribosome-inactivating protein from Momordica charantia, with NADP(+) and NADPH has been investigated by X-ray diffraction analysis of complexes generated by co-crystallization and crystal soaking. It is known that the proteins of this family readily cleave the adenine-ribose bond of adenosine and related nucleotides in the crystal, leaving the product, adenine, bound to the enzyme active site. Surprisingly, the nicotinamide-ribose bond of oxidized NADP(+) is cleaved, leaving nicotinamide bound in the active site in the same position but in a slightly different orientation to that of the five-membered ring of adenine. No binding or cleavage of NADPH was observed at pH 7.4 in these experiments. These observations are in accord with current views of the enzyme mechanism and may contribute to ongoing searches for effective inhibitors.

Nicotinamidase modulation of NAD+ biosynthesis and nicotinamide levels separately affect reproductive development and cell survival in C. elegans.

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Vrablik, Tracy L; Huang, Li; Lange, Stephanie E; Hanna-Rose, Wendy

2009-11-01

Nicotinamide adenine dinucleotide (NAD(+)) is a central molecule in cellular metabolism and an obligate co-substrate for NAD(+)-consuming enzymes, which regulate key biological processes such as longevity and stress responses. Although NAD(+) biosynthesis has been intensely studied, little analysis has been done in developmental models. We have uncovered novel developmental roles for a nicotinamidase (PNC), the first enzyme in the NAD(+) salvage pathway of invertebrates. Mutations in the Caenorhabditis elegans nicotinamidase PNC-1 cause developmental and functional defects in the reproductive system; the development of the gonad is delayed, four uterine cells die by necrosis and the mutant animals are egg-laying defective. The temporal delay in gonad development results from depletion of the salvage pathway product NAD(+), whereas the uv1 cell necrosis and egg-laying defects result from accumulation of the substrate nicotinamide. Thus, regulation of both substrate and product level is key to the biological activity of PNC-1. We also find that diet probably affects the levels of these metabolites, as it affects phenotypes. Finally, we identified a secreted isoform of PNC-1 and confirmed its extracellular localization and functional activity in vivo. We demonstrate that nicotinamide phosphoribosyltransferase (Nampt), the equivalent enzyme in nicotinamide recycling to NAD(+) in vertebrates, can functionally substitute for PNC-1. As Nampt is also secreted, we postulate an evolutionarily conserved extracellular role for NAD(+) biosynthetic enzymes during development and physiology.

Enhancing NAD+ Salvage Pathway Reverts the Toxicity of Primary Astrocytes Expressing Amyotrophic Lateral Sclerosis-linked Mutant Superoxide Dismutase 1 (SOD1).

Science.gov (United States)

Harlan, Benjamin A; Pehar, Mariana; Sharma, Deep R; Beeson, Gyda; Beeson, Craig C; Vargas, Marcelo R

2016-05-13

Nicotinamide adenine dinucleotide (NAD(+)) participates in redox reactions and NAD(+)-dependent signaling pathways. Although the redox reactions are critical for efficient mitochondrial metabolism, they are not accompanied by any net consumption of the nucleotide. On the contrary, NAD(+)-dependent signaling processes lead to its degradation. Three distinct families of enzymes consume NAD(+) as substrate: poly(ADP-ribose) polymerases, ADP-ribosyl cyclases (CD38 and CD157), and sirtuins (SIRT1-7). Because all of the above enzymes generate nicotinamide as a byproduct, mammalian cells have evolved an NAD(+) salvage pathway capable of resynthesizing NAD(+) from nicotinamide. Overexpression of the rate-limiting enzyme in this pathway, nicotinamide phosphoribosyltransferase, increases total and mitochondrial NAD(+) levels in astrocytes. Moreover, targeting nicotinamide phosphoribosyltransferase to the mitochondria also enhances NAD(+) salvage pathway in astrocytes. Supplementation with the NAD(+) precursors nicotinamide mononucleotide and nicotinamide riboside also increases NAD(+) levels in astrocytes. Amyotrophic lateral sclerosis (ALS) is caused by the progressive degeneration of motor neurons in the spinal cord, brain stem, and motor cortex. Superoxide dismutase 1 (SOD1) mutations account for up to 20% of familial ALS and 1-2% of apparently sporadic ALS cases. Primary astrocytes isolated from mutant human superoxide dismutase 1-overexpressing mice as well as human post-mortem ALS spinal cord-derived astrocytes induce motor neuron death in co-culture. Increasing total and mitochondrial NAD(+) content in ALS astrocytes increases oxidative stress resistance and reverts their toxicity toward co-cultured motor neurons. Taken together, our results suggest that enhancing the NAD(+) salvage pathway in astrocytes could be a potential therapeutic target to prevent astrocyte-mediated motor neuron death in ALS. © 2016 by The American Society for Biochemistry and Molecular

Crystal structure of Sus scrofa quinolinate phosphoribosyltransferase in complex with nicotinate mononucleotide.

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Hyung-Seop Youn

Full Text Available We have determined the crystal structure of porcine quinolinate phosphoribosyltransferase (QAPRTase in complex with nicotinate mononucleotide (NAMN, which is the first crystal structure of a mammalian QAPRTase with its reaction product. The structure was determined from protein obtained from the porcine kidney. Because the full protein sequence of porcine QAPRTase was not available in either protein or nucleotide databases, cDNA was synthesized using reverse transcriptase-polymerase chain reaction to determine the porcine QAPRTase amino acid sequence. The crystal structure revealed that porcine QAPRTases have a hexameric structure that is similar to other eukaryotic QAPRTases, such as the human and yeast enzymes. However, the interaction between NAMN and porcine QAPRTase was different from the interaction found in prokaryotic enzymes, such as those of Helicobacter pylori and Mycobacterium tuberculosis. The crystal structure of porcine QAPRTase in complex with NAMN provides a structural framework for understanding the unique properties of the mammalian QAPRTase active site and designing new antibiotics that are selective for the QAPRTases of pathogenic bacteria, such as H. pylori and M. tuberculosis.

Interactive effects of salinity stress and nicotinamide on physiological and biochemical parameters of Faba bean plant

International Nuclear Information System (INIS)

Abdelhamid, Magdi T; Sadak, Mervat Sh; Schmidhalter, Urs; El Saady, Abdel Kareem M.

2013-01-01

A possible survival strategy for plants under saline conditions is to use some compounds that could alleviate the salt stress effect. One of these compounds is nicotinamide (vitamin B3/niacin). The effect of exogenous application of nicotinamide with different concentrations (0,200 or 400 mg l-1) on faba bean (Vicia faba L.) plant grown at different NaCl levels (0,50 or 100 mM) was investigated in the wire house of the National Research Centre, Cairo, Egypt. Salinity stress significantly reduced the photosynthetic pigments, polysaccharides, total carbohydrates, total-N contents of shoot, plant height, leaves number, fresh and dry weights of shoot, seed yield, total carbohydrates and total crude protein of the yielded seeds compared with those of the control plants. In contrast, salinity induced marked increases in sucrose, total soluble sugars, total free amino acids, proline, lipid peroxidation product (MDA) and some oxidative enzymes (polyphenol-oxidase and peroxidase). Also, salinity stress increased Na+ contents with the decreases of other macro and micro elements contents (P, K+, Mg_2+, Ca_2+, Fe_2+, Mn_2+, Zn_2+ and Cu_2+) of shoots and the yielded seeds of faba bean. Foliar spraying of nicotinamide alleviated the adverse effects of salinity stress through increased the photosynthetic pigments, polysaccharides, total carbohydrates, total N concentration of shoot, plant height, leaves number, fresh and dry weights of shoot, and seed yield as well as, sucrose, total soluble sugars, total free amino acids and proline, compared with those of the corresponding salinity levels, while decreased lipid peroxidation product as malondialdehyde (MDA) and the oxidative enzymes (polyphenol oxidase and peroxidase enzymes). Nicotinamide inhibited the uptake of Na+ and accelerated the accumulation of P, K+, Mg_2+, Ca_2+, Fe_2+, Mn_2+, Zn_2+ and Cu_2+ concentrations in the shoots of salt stressed plants and enhanced total carbohydrate and total crude protein percentage and

L-glutamine supplementation prevents the development of experimental diabetic cardiomyopathy in streptozotocin-nicotinamide induced diabetic rats.

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Sachin L Badole

Full Text Available The objective of the present investigation was to evaluate the effect of L-glutamine on cardiac myopathy in streptozotocin-nicotinamide induced diabetic rats. Diabetes was induced in overnight fasted Sprague Dawely rats by using intraperitonial injection of streptozotocin (55 mg/kg. Nicotinamide (100 mg/kg, i.p. was administered 20 min before administration of streptozotocin. Experimental rats were divided into Group I: non-diabetic control (distilled water; 10 ml/kg, p.o., II: diabetic control (distilled water, 10 ml/kg, p.o., III: L-glutamine (500 mg/kg, p.o. and IV: L-glutamine (1000 mg/kg, p.o.. All groups were diabetic except group I. The plasma glucose level, body weight, electrocardiographic abnormalities, hemodynamic changes and left ventricular contractile function, biological markers of cardiotoxicity, antioxidant markers were determined after 4 months after STZ with nicotinamide injection. Histopathological changes of heart tissue were carried out by using H and E stain. L-glutamine treatment improved the electrocardiographic, hemodynamic changes; LV contractile function; biological markers; oxidative stress parameters and histological changes in STZ induced diabetic rats. Results from the present investigation demonstrated that L-glutamine has seemed a cardioprotective activity.

Synthesis and antifungal activity of nicotinamide derivatives as succinate dehydrogenase inhibitors.

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Ye, Yong-Hao; Ma, Liang; Dai, Zhi-Cheng; Xiao, Yu; Zhang, Ying-Ying; Li, Dong-Dong; Wang, Jian-Xin; Zhu, Hai-Liang

2014-05-07

Thirty-eight nicotinamide derivatives were designed and synthesized as potential succinate dehydrogenase inhibitors (SDHI) and precisely characterized by (1)H NMR, ESI-MS, and elemental analysis. The compounds were evaluated against two phytopathogenic fungi, Rhizoctonia solani and Sclerotinia sclerotiorum, by mycelia growth inhibition assay in vitro. Most of the compounds displayed moderate activity, in which, 3a-17 exhibited the most potent antifungal activity against R. solani and S. sclerotiorum with IC50 values of 15.8 and 20.3 μM, respectively, comparable to those of the commonly used fungicides boscalid and carbendazim. The structure-activity relationship (SAR) of nicotinamide derivatives demonstrated that the meta-position of aniline was a key position contributing to the antifungal activity. Inhibition activities against two fungal SDHs were tested and achieved the same tendency with the data acquired from in vitro antifungal assay. Significantly, 3a-17 was demonstrated to successfully suppress disease development in S. sclerotiorum infected cole in vivo. In the molecular docking simulation, sulfur and chlorine of 3a-17 were bound with PHE291 and PRO150 of the SDH homology model, respectively, which could explain the probable mechanism of action between the inhibitory and target protein.

Coenzyme Recognition and Gene Regulation by a Flavin Mononucleotide Riboswitch

Energy Technology Data Exchange (ETDEWEB)

Serganov, A.; Huang, L; Patel, D

2009-01-01

The biosynthesis of several protein cofactors is subject to feedback regulation by riboswitches. Flavin mononucleotide (FMN)-specific riboswitches also known as RFN elements, direct expression of bacterial genes involved in the biosynthesis and transport of riboflavin (vitamin B2) and related compounds. Here we present the crystal structures of the Fusobacterium nucleatum riboswitch bound to FMN, riboflavin and antibiotic roseoflavin. The FMN riboswitch structure, centred on an FMN-bound six-stem junction, does not fold by collinear stacking of adjacent helices, typical for folding of large RNAs. Rather, it adopts a butterfly-like scaffold, stapled together by opposingly directed but nearly identically folded peripheral domains. FMN is positioned asymmetrically within the junctional site and is specifically bound to RNA through interactions with the isoalloxazine ring chromophore and direct and Mg{sup 2+}-mediated contacts with the phosphate moiety. Our structural data, complemented by binding and footprinting experiments, imply a largely pre-folded tertiary RNA architecture and FMN recognition mediated by conformational transitions within the junctional binding pocket. The inherent plasticity of the FMN-binding pocket and the availability of large openings make the riboswitch an attractive target for structure-based design of FMN-like antimicrobial compounds. Our studies also explain the effects of spontaneous and antibiotic-induced deregulatory mutations and provided molecular insights into FMN-based control of gene expression in normal and riboflavin-overproducing bacterial strains.

Nicotinamide dependence of uropathogenic Escherichia coli UTI89 and application of nadB as a neutral insertion site.

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Li, Zhaoli; Bouckaert, Julie; Deboeck, Francine; De Greve, Henri; Hernalsteens, Jean-Pierre

2012-03-01

NAD and NADP are ubiquitous in the metabolism of Escherichia coli K-12. NAD auxotrophy can be rendered by mutation in any of the three genes nadB, nadA and nadC. The nadB and nadA genes were defined as antivirulence loci in Shigella spp., as a mutation (mainly in nadB) disrupting the synthesis of quinolinate is required for virulence. Uropathogenic E. coli (UPEC) isolates from acute cystitis patients, exhibiting nicotinamide auxotrophy, were of serotype O18 : K1 : H7. E. coli UTI89, the model uropathogenic and O18 : K1 : H7 strain, requires nicotinamide or quinolinate for growth. A mutation in the nadB gene, encoding L-aspartate oxidase, was shown to be responsible for the nicotinamide requirement of UTI89. This was further confirmed by complementation of UTI89 with a recombinant plasmid harbouring the nadB gene of E. coli K-12. An Ala28Val point mutant of the recombinant plasmid failed to support the growth of UTI89 in minimal medium. This proves that the Ala28Val mutation in the NadB gene of UTI89 completely impedes de novo synthesis of nicotinamide. In spontaneous prototrophic revertants of UTI89, the nadB gene has a Val28Ala mutation. Both analyses implicate that the nicotinamide auxotrophy of UTI89 is caused by a single Ala28Val mutation in NadB. We showed that the same mutation is also present in other NAD auxotrophic E. coli O18 strains. No significant differences were observed between the virulence of isogenic NAD auxotrophic and prototrophic strains in the murine ascending urinary tract infection model. Considering these data, we applied the nadB locus as a neutral site for DNA insertions in the bacterial chromosome. We successfully restored the parental phenotype of a fimH mutant by inserting fimH, with a synthetic em7 promoter, into the nadB gene. This neutral insertion site is of significance for further research on the pathogenicity of UPEC.

Investigations of the metabolism of NAD in embryonic neural tissue of mice after irradiation with X-rays

International Nuclear Information System (INIS)

Beuningen, M. van.

1974-01-01

Female mice of an institutes own inbred strain were killed on the 9th-13th day of pregnancy and the embryos were removed by caesarian section. The NAD content and protein content in the embryonic neural tissue of the mice increase the most from the 10th to 11th day. There is a relationship between NAD quantity and increase in size measured by the protein content. The enzymal activity of the NMN pyrophosphorylase runs parallel to the NAD rise and fall except for on the 11th day on which the enzyme increases further. The NAD biosynthesis from nicotinamide measured by the incorporation of 14-C nicotinamide in the NAD rises from the 10th to the 13th day. If one refers the incorporation to the protein content, however, the NAD synthesis falls from the 10th day onwards. An increase of the NAD content in the embryonic brain by the addition of nicotinamide in a high dose was not possible on the 10th and 12th day, whereas a clear increase was registered in the mother animal liver. Following an X-radiation with 200 R on the 9th day, the NAD content/brain dropped on the 11th day to its lowest point and had reached its normal value again on the 13th day, contrary to the protein content which only decreases on the 11th day. If one refers the NAD content, however, to protein quantity, then this only falls on the 10th day and rises on the 11th day almost to the normal value and has reached the latter by the 12th day. The NMN pyrophosphorylase activity falls on the 10th and 11th day, has its normal value on the 12th day and exceeds it on the 13th day. If one refers the enzyme activity to protein content, then it drops on the 10th day, reaches its lowest value on the 11th day, has its normal value on the 12th day and shoots above it on the 13th day. On the 10th day, the NAD content falls only after an X-ray with 200 R given on the 9th day, whereas the protein content remains constant. The NAD content does not change in the region of 50 to 150 R. (orig./LH) [de

A fluorescence study of the molecular interactions of harmane with the nucleobases, their nucleosides and mononucleotides.

Science.gov (United States)

Balón, M; Muñoz, M A; Carmona, C; Guardado, P; Galán, M

1999-07-19

Fluorescence binding studies of harmane to the elemental components of the nucleic acids were undertaken to investigate the origin of the interaction between the drug and DNA. Most of the tested substrates have been found to induce hypochromism in the absorption spectrum of harmane and to quench its fluorescence. The quenching process induced by the nucleobases and their nucleosides is mainly due to the formation of ground state 1:1 complexes. However, in the case of the mononucleotides a dynamic quenching component is also observed. This quenching component is likely due to the excited state interaction of harmane with the phosphate group of the nucleotides. UV-vis spectral changes and quenching measurements have been used to quantify the ground state association constants of the complexes and the quenching rate constants.

Meat Intake and the Dose of Vitamin B – Nicotinamide: Cause of the Causes of Disease Transitions, Health Divides, and Health Futures?

Directory of Open Access Journals (Sweden)

Lisa J Hill

2017-05-01

Full Text Available Meat and vitamin B 3 – nicotinamide – intake was high during hunter-gatherer times. Intake then fell and variances increased during and after the Neolithic agricultural revolution. Health, height, and IQ deteriorated. Low dietary doses are buffered by ‘welcoming’ gut symbionts and tuberculosis that can supply nicotinamide, but this co-evolved homeostatic metagenomic strategy risks dysbioses and impaired resistance to pathogens. Vitamin B 3 deficiency may now be common among the poor billions on a low-meat diet. Disease transitions to non-communicable inflammatory disorders (but longer lives may be driven by positive ‘meat transitions’. High doses of nicotinamide lead to reduced regulatory T cells and immune intolerance. Loss of no longer needed symbiotic ‘old friends’ compounds immunological over-reactivity to cause allergic and auto-immune diseases. Inhibition of nicotinamide adenine dinucleotide consumers and loss of methyl groups or production of toxins may cause cancers, metabolic toxicity, or neurodegeneration. An optimal dosage of vitamin B 3 could lead to better health, but such a preventive approach needs more equitable meat distribution. Some people may require personalised doses depending on genetic make-up or, temporarily, when under stress.

Nicotinamide Inhibits Ethanol-Induced Caspase-3 and PARP-1 Over-activation and Subsequent Neurodegeneration in the Developing Mouse Cerebellum.

Science.gov (United States)

Ieraci, Alessandro; Herrera, Daniel G

2018-06-01

Fetal alcohol spectrum disorder (FASD) is the principal preventable cause of mental retardation in the western countries resulting from alcohol exposure during pregnancy. Ethanol-induced massive neuronal cell death occurs mainly in immature neurons during the brain growth spurt period. The cerebellum is one of the brain areas that are most sensitive to ethanol neurotoxicity. Currently, there is no effective treatment that targets the causes of these disorders and efficient treatments to counteract or reverse FASD are desirable. In this study, we investigated the effects of nicotinamide on ethanol-induced neuronal cell death in the developing cerebellum. Subcutaneous administration of ethanol in postnatal 4-day-old mice induced an over-activation of caspase-3 and PARP-1 followed by a massive neurodegeneration in the developing cerebellum. Interestingly, treatment with nicotinamide, immediately or 2 h after ethanol exposure, diminished caspase-3 and PARP-1 over-activation and reduced ethanol-induced neurodegeneration. Conversely, treatment with 3-aminobenzadine, a specific PARP-1 inhibitor, was able to completely block PARP-1 activation, but not caspase-3 activation or ethanol-induced neurodegeneration in the developing cerebellum. Our results showed that nicotinamide reduces ethanol-induced neuronal cell death and inhibits both caspase-3 and PARP-1 alcohol-induced activation in the developing cerebellum, suggesting that nicotinamide might be a promising and safe neuroprotective agent for treating FASD and other neurodegenerative disorders in the developing brain that shares similar cell death pathways.

A case of vesicular cutaneous lupus erythematosus in a Border collie successfully treated with topical tacrolimus and nicotinamide-tetracycline.

Science.gov (United States)

Lehner, Georg M; Linek, Monika

2013-12-01

Canine vesicular cutaneous lupus erythematosus (VCLE) is an autoimmune skin disease of the Shetland sheepdog and rough collie, which manifests as an erosive dermatitis of sparsely haired skin of the ventrum and concave pinnae. Reported treatment consists of immunosuppression with glucocorticoids alone or in combination with azathioprine, but successful treatment is unpredictable. To report on the treatment of VCLE in a Border collie dog with topical 0.1% tacrolimus and nicotinamide in combination with tetracycline. An 8-year-old male neutered Border collie was presented with multiple coalescing erosions on the ventral abdomen, groin and axillae and ulceration on the oral commissures. Clinical presentation, routine diagnostics, histology and immunohistochemistry were consistent with VCLE. Remission was achieved with topical 0.1% tacrolimus and combination therapy of nicotinamide and tetracycline. This dog responded well to treatment with topical 0.1% tacrolimus, nicotinamide-tetracycline and sun avoidance. Complete remission was achieved after 2.5 months, and the dog was lesion free during a 1 year follow-up period. © 2013 ESVD and ACVD.

Formation of nicotinamide ribose diphosphate ribose, a new metabolite of the NAD pathway, by growing mycelium of Aspergillus niger

International Nuclear Information System (INIS)

Kuwahara, Masaaki

1976-01-01

A new step of NAD metabolism was shown in Aspergillus niger. Radioactive nicotinic acid and nicotinamide were incorporated into nicotinamide ribose diphosphate ribose (NAm-RDPR), which had been isolated from the culture filtrate. Its content in the culture medium increased with an increase of culture time, and this compound was proved to be a terminal metabolite in the NAD pathway. The experimental results also showed that the Preiss-Handler pathway and the NAD cycling system function in the NAD biosynthesis in A. niger. A part of the radioactive precursors was also incorporated into an unknown compound. (auth.)

Eugenosedin-A improves glucose metabolism and inhibits MAPKs expression in streptozotocin/nicotinamide-induced diabetic rats

Directory of Open Access Journals (Sweden)

Kuo-Ping Shen

2018-03-01

Full Text Available This study examined the effects of eugenosedin-A (Eu-A in a streptozotocin (STZ/nicotinamide-induced rat model of type II diabetes mellitus (T2DM. Six-week-old Sprague–Dawley rats were randomly divided into three groups: (1 RD group, normal rats fed a regular diet (RD, (2 DM group, T2DM rats fed a high-fat diet, and (3 Eu-A group, T2DM rats fed a high fat diet plus oral Eu-A (5 mg/kg/day. After 30 days, the DM group had higher body weight, higher blood glucose and lower insulin levels than the RD group. The DM group also had increased protein expression of glycogen synthase kinase (GSK in liver and skeletal muscle and decreased protein expression of insulin receptor (IR, insulin receptor substrate-1 (IRS-1, IRS-2, AMP-activated protein kinase (AMPK, glucose transporter-4 (GLUT-4, glucokinase (GCK, and peroxisome proliferator-activated receptor γ (PPAR-γ. STZ/nicotinamide-induced T2DM increased the expression of mitogen-activated protein kinases (MAPKs: p38, ERK, JNK and inflammatory p65 protein. In the Eu-A treated T2DM rats, however, blood glucose was attenuated and the insulin concentration stimulated. Changes in IR, IRS-1 and IRS-2 proteins as well as AMPK, GLUT-4, GCK, GSK, PPAR-γ, MAPKs, and inflammatory p65 proteins were ameliorated. These results suggested that Eu-A alleviates STZ/nicotinamide-induced hyperglycemia by improving insulin levels and glucose metabolism, and inhibiting the MAPKs- and p65-mediated inflammatory pathway.

Uptake of [14C]nicotinic acid and [14C]nicotinamide by Bordetella pertussis

International Nuclear Information System (INIS)

McPheat, W.L.; Wardlaw, A.C.

1980-01-01

Bordetella pertussis has an absolute requirement for either nicotinic acid (NA) or nicotinamide (ND), both being equally effective in supporting growth. The results of an investigation to compare the rates of uptake of NA and ND, to determine the influence of factors such as energy source and temperature on uptake, and to measure the Ksub(m) and Vsub(max) values are reported. (Auth.)

Simultaneous measurement of NAD metabolome in aged mice tissue using liquid chromatography tandem-mass spectrometry.

Science.gov (United States)

Yaku, Keisuke; Okabe, Keisuke; Nakagawa, Takashi

2018-06-01

Nicotinamide adenine dinucleotide (NAD) is a major co-factor that mediates multiple biological processes including redox reaction and gene expression. Recently, NAD metabolism has received considerable attention because administration of NAD precursors exhibited beneficial effects against aging-related metabolic disorders in animals. Although numerous studies have reported that NAD levels decline with aging in multiple animal tissues, the pathway and kinetics of NAD metabolism in aged organs are not completely understood. To determine the NAD metabolism upon aging, we developed targeted metabolomics based on an LC/MS/MS system. Our method is simple and applicable to crude biological samples, including culture cells and animal tissues. Unlike a conventional enzymatic cycling assay, our approach can determine NAD and NADH (reduced form of NAD) by performing a single sample preparation. Further, we validated our method using biological samples and investigated the alteration of the NAD metabolome during aging. Consistent with previous reports, the NAD levels in the liver and skeletal muscle decreased with aging. Further, we detected a significant increase in nicotinamide mononucleotide and nicotinamide riboside in the kidney upon aging. The LC/MS/MS-based NAD metabolomics that we have developed is extensively applicable to biomedical studies, and the results will present innovative ideas for the aging studies, especially for that of NAD metabolism. Copyright © 2018 John Wiley & Sons, Ltd.

Density and viscosity study of nicotinic acid and nicotinamide in dilute aqueous solutions at and around the temperature of the maximum density of water

International Nuclear Information System (INIS)

Dhondge, Sudhakar S.; Dahasahasra, Prachi N.; Paliwal, Lalitmohan J.; Deshmukh, Dinesh W.

2014-01-01

Highlights: • Volumetric and transport behaviour of aqueous solutions of important vitamins are reported. • Various interactions of nicotinic acid and nicotinamide with water have been reported. • The temperature dependence of interactions between solute and solvent is discussed. • The study indicates that nicotinamide is more hydrated as compared to nicotinic acid. - Abstract: In the present study, we report experimental densities (ρ) and viscosities (η) of aqueous solutions of nicotinic acid and nicotinamide within the concentration range (0 to 0.1) mol · kg −1 at T = (275.15, 277.15 and 279.15) K. These parameters are then used to obtain thermodynamic and transport functions such as apparent molar volume of solute (V ϕ ), limiting apparent molar volume of solute (V ϕ 0 ), limiting apparent molar expansivity of solute (E ϕ 0 ), coefficient of thermal expansion (α ∗ ), Jones–Dole equation viscosity A, B and D coefficients, temperature derivative of B coefficient i.e. (dB/dT) and hydration number (n H ), etc. The activation parameters of viscous flow for the binary mixtures have been determined and discussed in terms of Eyring’s transition state theory. These significant parameters are helpful to study the structure promoting or destroying tendency of solute and various interactions present in (nicotinic acid + water) and (nicotinamide + water) binary mixtures

Tunable negative thermal expansion related with the gradual evolution of antiferromagnetic ordering in antiperovskite manganese nitrides Ag{sub 1−x}NMn{sub 3+x} (0 ≤ x ≤ 0.6)

Energy Technology Data Exchange (ETDEWEB)

Lin, J. C.; Tong, P., E-mail: tongpeng@issp.ac.cn; Lin, S.; Wang, B. S.; Song, W. H. [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); Tong, W.; Zou, Y. M. [High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031 (China); Sun, Y. P., E-mail: ypsun@issp.ac.cn [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China); High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031 (China); Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093 (China)

2015-02-23

The thermal expansion and magnetic properties of antiperovskite manganese nitrides Ag{sub 1−x}NMn{sub 3+x} were reported. The substitution of Mn for Ag effectively broadens the temperature range of negative thermal expansion and drives it to cryogenic temperatures. As x increases, the paramagnetic (PM) to antiferromagnetic (AFM) phase transition temperature decreases. At x ∼ 0.2, the PM-AFM transition overlaps with the AFM to glass-like state transition. Above x = 0.2, two new distinct magnetic transitions were observed: One occurs above room temperature from PM to ferromagnetic (FM), and the other one evolves at a lower temperature (T{sup *}) below which both AFM and FM orderings are involved. Further, electron spin resonance measurement suggests that the broadened volume change near T{sup *} is closely related with the evolution of Γ{sup 5g} AFM ordering.

Protein Engineering for Nicotinamide Coenzyme Specificity in Oxidoreductases: Attempts and Challenges.

Science.gov (United States)

Chánique, Andrea M; Parra, Loreto P

2018-01-01

Oxidoreductases are ubiquitous enzymes that catalyze an extensive range of chemical reactions with great specificity, efficiency, and selectivity. Most oxidoreductases are nicotinamide cofactor-dependent enzymes with a strong preference for NADP or NAD. Because these coenzymes differ in stability, bioavailability and costs, the enzyme preference for a specific coenzyme is an important issue for practical applications. Different approaches for the manipulation of coenzyme specificity have been reported, with different degrees of success. Here we present various attempts for the switching of nicotinamide coenzyme preference in oxidoreductases by protein engineering. This review covers 103 enzyme engineering studies from 82 articles and evaluates the accomplishments in terms of coenzyme specificity and catalytic efficiency compared to wild type enzymes of different classes. We analyzed different protein engineering strategies and related them with the degree of success in inverting the cofactor specificity. In general, catalytic activity is compromised when coenzyme specificity is reversed, however when switching from NAD to NADP, better results are obtained. In most of the cases, rational strategies were used, predominantly with loop exchange generating the best results. In general, the tendency of removing acidic residues and incorporating basic residues is the strategy of choice when trying to change specificity from NAD to NADP, and vice versa . Computational strategies and algorithms are also covered as helpful tools to guide protein engineering strategies. This mini review aims to give a general introduction to the topic, giving an overview of tools and information to work in protein engineering for the reversal of coenzyme specificity.

Combined experimental and computational studies of pyrazinamide and nicotinamide in the context of crystal engineering and thermodynamics

DEFF Research Database (Denmark)

Jarzembska, Katarzyna N.; Hoser, Anna Agnieszka; Kamiński, Radosław

2014-01-01

and computational analysis of the β form of pyrazinamide and α form of nicotinamide. Static electron density distribution is obtained through application of Hansen and Coppens multipolar formalism, and further analyzed via Baders quantum theory of atoms in molecules (QTAIM). Geometrical and electron density...

Maternal intake of fat, riboflavin and nicotinamide and the risk of having offspring with congenital heart defects

NARCIS (Netherlands)

Smedts, H.P.M.; Rakhshandehroo, M.; Verkleij-Hagoort, A.C.; Vries, de J.H.M.; Ottenkamp, J.; Steegers, E.A.P.; Steegers-Theunissen, R.P.M.

2008-01-01

With the exception of studies on folic acid, little evidence is available concerning other nutrients in the pathogenesis of congenital heart defects (CHDs). Fatty acids play a central role in embryonic development, and the B-vitamins riboflavin and nicotinamide are co-enzymes in lipid metabolism.

Maternal intake of fat, riboflavin and nicotinamide and the risk of having offspring with congenital heart defects

NARCIS (Netherlands)

Smedts, Huberdina P. M.; Rakhshandehroo, Maryam; Verkleij-Hagoort, Anna C.; de Vries, Jeanne H. M.; Ottenkamp, Jaap; Steegers, Eric A. P.; Steegers-Theunissen, Régine P. M.

2008-01-01

BACKGROUND: With the exception of studies on folic acid, little evidence is available concerning other nutrients in the pathogenesis of congenital heart defects (CHDs). Fatty acids play a central role in embryonic development, and the B-vitamins riboflavin and nicotinamide are co-enzymes in lipid

Synthesis and evaluation of novel radioiodinated nicotinamides for malignant melanoma

Energy Technology Data Exchange (ETDEWEB)

Liu Xiang; Pham, Tien Q.; Berghofer, Paula; Chapman, Janette; Greguric, Ivan; Mitchell, Peter; Mattner, Filomena; Loc' h, Christian [Radiopharmaceuticals Research Institute, Australian Nuclear Science and Technology Organisation, Sydney, NSW 2234 (Australia); Katsifis, Andrew [Radiopharmaceuticals Research Institute, Australian Nuclear Science and Technology Organisation, Sydney, NSW 2234 (Australia)], E-mail: akx@ansto.gov.au

2008-10-15

Introduction: A series of iodonicotinamides based on the melanin-binding iodobenzamide compound N-2-diethylaminoethyl-4-iodobenzamide was prepared and evaluated for the potential imaging and staging of disseminated metastatic melanoma. Methods: [{sup 123}I]Iodonicotinamides were prepared by iododestannylation reactions using no-carrier-added iodine-123 and evaluated in vivo by biodistribution and competition studies and by single photon emission computed tomography (SPECT) imaging in black and albino nude mice bearing B16F0 murine melanotic and A375 human amelanotic melanoma tumours, respectively. Results: The iodonicotinamides displayed low-affinity binding for {sigma}{sub 1}-{sigma}{sub 2} receptors (K{sub i}>300 nM). In biodistribution studies in mice, N-(2-(diethylamino)ethyl)-5-[{sup 123}I]iodonicotinamide ([{sup 123}I]1) exhibited the fastest and highest uptake of the nicotinamide series in the B16F0 tumour at 1 h ({approx}8% ID/g), decreasing slowly over time. No uptake was observed in the A375 tumour. Clearance from the animals by urinary excretion was more rapid for N-alkyl-nicotinamides than for piperazinyl derivatives. At 1 h postinjection, the urinary excretion was 66% ID for [{sup 123}I]1, while the gastrointestinal tract amounted to 17% ID. Haloperidol was unable to reduce the uptake of [{sup 123}I]1 in pigmented mice, indicating that this uptake was likely due to an interaction with melanin. SPECT imaging of [{sup 123}I]1 in black mice bearing the B16F0 melanoma indicated that the radioactivity was predominately located in the tumour and eyes. No specific localisation was observed in nude mice bearing A375 amelanotic tumours. Conclusion: These findings suggest that [{sup 123}I]1, which displays high tumour uptake with rapid clearance from the body, could be a promising imaging agent for the detection of melanotic tumours.

Crystallization and preliminary X-ray crystallographic analysis of quinolinate phosphoribosyltransferase from porcine kidney in complex with nicotinate mononucleotide

International Nuclear Information System (INIS)

Youn, Hyung-Seop; Kim, Mun-Kyoung; Kang, Gil Bu; Kim, Tae Gyun; An, Jun Yop; Lee, Jung-Gyu; Park, Kyoung Ryoung; Lee, Youngjin; Fukuoka, Shin-Ichi; Eom, Soo Hyun

2012-01-01

Crystals of S. scrofa quinolinate phosphoribosyltransferase purified from porcine kidney in complex with nicotinate mononucleotidewere obtained and diffraction data were collected and processed to 2.1 Å resolution. Quinolinate phosphoribosyltransferase (QAPRTase) is a key enzyme in NAD biosynthesis; it catalyzes the formation of nicotinate mononucleotide (NAMN) from quinolinate and 5-phosphoribosyl-1-pyrophosphate. In order to elucidate the mechanism of NAMN biosynthesis, crystals of Sus scrofa QAPRTase (Ss-QAPRTase) purified from porcine kidney in complex with NAMN were obtained and diffraction data were collected and processed to 2.1 Å resolution. The Ss-QAPRTase–NAMN cocrystals belonged to space group P321, with unit-cell parameters a = 119.1, b = 119.1, c = 93.7 Å, γ = 120.0°. The Matthews coefficient and the solvent content were estimated as 3.10 Å 3 Da –1 and 60.3%, respectively, assuming the presence of two molecules in the asymmetric unit

The B vitamins nicotinamide (B3) and riboflavin (B2) stimulate metamorphosis in larvae of the deposit-feeding polychaete Capitella teleta: implications for a sensory ligand-gated ion channel.

Science.gov (United States)

Burns, Robert T; Pechenik, Jan A; Biggers, William J; Scavo, Gia; Lehman, Christopher

2014-01-01

Marine sediments can contain B vitamins, presumably incorporated from settled, decaying phytoplankton and microorganisms associated with decomposition. Because B vitamins may be advantageous for the energetically intensive processes of metamorphosis, post-metamorphic growth, and reproduction, we tested several B vitamins to determine if they would stimulate larvae of the deposit-feeding polychaete Capitella teleta to settle and metamorphose. Nicotinamide and riboflavin individually stimulated larvae of C. teleta to settle and metamorphose, generally within 1-2 hours at nicotinamide concentrations as low as 3 µM and riboflavin concentrations as low as 50 µM. More than 80% of the larvae metamorphosed within 30 minutes at a nicotinamide concentration of 7 µM. The pyridine channel agonist pyrazinecarboxamide also stimulated metamorphosis at very low concentrations. In contrast, neither lumichrome, thiamine HCl, pyridoxine HCl, nor vitamin B12 stimulated larvae of C. teleta to metamorphose at concentrations as high as 500 µM. Larvae also did not metamorphose in response to either nicotinamide or pyrazinecarboxamide in calcium-free seawater or with the addition of 4-acetylpyridine, a competitive inhibitor of the pyridine receptor. Together, these results suggest that larvae of C. teleta are responding to nicotinamide and riboflavin via a chemosensory pyridine receptor similar to that previously reported to be present on crayfish chela and involved with food recognition. Our data are the first to implicate B vitamins as possible natural chemical settlement cues for marine invertebrate larvae.

The B Vitamins Nicotinamide (B3) and Riboflavin (B2) Stimulate Metamorphosis in Larvae of the Deposit-Feeding Polychaete Capitella teleta: Implications for a Sensory Ligand-Gated Ion Channel

Science.gov (United States)

Burns, Robert T.; Pechenik, Jan A.; Biggers, William J.; Scavo, Gia; Lehman, Christopher

2014-01-01

Marine sediments can contain B vitamins, presumably incorporated from settled, decaying phytoplankton and microorganisms associated with decomposition. Because B vitamins may be advantageous for the energetically intensive processes of metamorphosis, post-metamorphic growth, and reproduction, we tested several B vitamins to determine if they would stimulate larvae of the deposit-feeding polychaete Capitella teleta to settle and metamorphose. Nicotinamide and riboflavin individually stimulated larvae of C. teleta to settle and metamorphose, generally within 1–2 hours at nicotinamide concentrations as low as 3 µM and riboflavin concentrations as low as 50 µM. More than 80% of the larvae metamorphosed within 30 minutes at a nicotinamide concentration of 7 µM. The pyridine channel agonist pyrazinecarboxamide also stimulated metamorphosis at very low concentrations. In contrast, neither lumichrome, thiamine HCl, pyridoxine HCl, nor vitamin B12 stimulated larvae of C. teleta to metamorphose at concentrations as high as 500 µM. Larvae also did not metamorphose in response to either nicotinamide or pyrazinecarboxamide in calcium-free seawater or with the addition of 4-acetylpyridine, a competitive inhibitor of the pyridine receptor. Together, these results suggest that larvae of C. teleta are responding to nicotinamide and riboflavin via a chemosensory pyridine receptor similar to that previously reported to be present on crayfish chela and involved with food recognition. Our data are the first to implicate B vitamins as possible natural chemical settlement cues for marine invertebrate larvae. PMID:25390040

Nicotinamide: a vitamin able to shift macrophage differentiation toward macrophages with restricted inflammatory features.

Science.gov (United States)

Weiss, Ronald; Schilling, Erik; Grahnert, Anja; Kölling, Valeen; Dorow, Juliane; Ceglarek, Uta; Sack, Ulrich; Hauschildt, Sunna

2015-11-01

The differentiation of human monocytes into macrophages is influenced by environmental signals. Here we asked in how far nicotinamide (NAM), a vitamin B3 derivative known to play a major role in nicotinamide adenine dinucleotide (NAD)-mediated signaling events, is able to modulate monocyte differentiation into macrophages developed in the presence of granulocyte macrophage colony-stimulating factor (GM-MØ) or macrophage colony-stimulating factor (M-MØ). We found that GM-MØ undergo biochemical, morphological and functional modifications in response to NAM, whereas M-MØ were hardly affected. GM-MØ exposed to NAM acquired an M-MØ-like structure while the LPS-induced production of pro-inflammatory cytokines and COX-derived eicosanoids were down-regulated. In contrast, NAM had no effect on the production of IL-10 or the cytochrome P450-derived eicosanoids. Administration of NAM enhanced intracellular NAD concentrations; however, it did not prevent the LPS-mediated drain on NAD pools. In search of intracellular molecular targets of NAM known to be involved in LPS-induced cytokine and eicosanoid synthesis, we found NF-κB activity to be diminished. In conclusion, our data show that vitamin B3, when present during the differentiation of monocytes into GM-MØ, interferes with biochemical pathways resulting in strongly reduced pro-inflammatory features. © The Author(s) 2015.

SAR and characterization of non-substrate isoindoline urea inhibitors of nicotinamide phosphoribosyltransferase (NAMPT)

Energy Technology Data Exchange (ETDEWEB)

Curtin, Michael L.; Heyman, H. Robin; Clark, Richard F.; Sorensen, Bryan K.; Doherty, George A.; Hansen, T. Matthew; Frey, Robin R.; Sarris, Kathy A.; Aguirre, Ana L.; Shrestha, Anurupa; Tu, Noah; Woller, Kevin; Pliushchev, Marina A.; Sweis, Ramzi F.; Cheng, Min; Wilsbacher, Julie L.; Kovar, Peter J.; Guo, Jun; Cheng, Dong; Longenecker, Kenton L.; Raich, Diana; Korepanova, Alla V.; Soni, Nirupama B.; Algire, Mikkel A.; Richardson, Paul L.; Marin, Violeta L.; Badagnani, Ilaria; Vasudevan, Anil; Buchanan, F.Greg; Maag, David; Chiang, Gary G.; Tse, Chris; Michaelides, Michael R. (AbbVie)

2017-08-01

Herein we disclose SAR studies that led to a series of isoindoline ureas which we recently reported were first-in-class, non-substrate nicotinamide phosphoribosyltransferase (NAMPT) inhibitors. Modification of the isoindoline and/or the terminal functionality of screening hit 5 provided inhibitors such as 52 and 58 with nanomolar antiproliferative activity and preclinical pharmacokinetics properties which enabled potent antitumor activity when dosed orally in mouse xenograft models. X-ray crystal structures of two inhibitors bound in the NAMPT active-site are discussed.

Nicotinamide and carbogen: relationship between pO2 and radiosensitivity in three tumour lines

International Nuclear Information System (INIS)

Martin, L.M.; Thomas, C.D.; Guichard, M.

1994-01-01

The effects of carbogen breathing, nicotinamide injection and their combination on tumour radiosensitivity were correlated with changes in tumour O 2 tension to determine the relationship between radiosensitivity and measured pO 2 . The radiosensitivity (in vivo-in vitro colony assay) and O 2 tension (computerized pO 2 histograph KIMOC 6650) of two human xenografted tumours (HRT18 and NA11 +) and one murine tumour (EMT6) were measured under similar experimental conditions. (author)

Nicotinamide adenosine dinucleotide level in dimethylsulfate-treated or UV-irradiated mouse epidermis

International Nuclear Information System (INIS)

Balard, B.; Giacomoni, P.U.

1989-01-01

The level of nicotinamide (NAD) has been determined in the epidermis of 30 mice. Its value is 0.63+-0.15 μg/mg protein. Upon treatment with dimethylsulfate (DMS), the level of NAD drops in a dosedependent fashion. This diminution is reversible when low doses of DMS are used. Upon irradiation with ultraviolet light, the level of NAD drops in the irradiated epidermis, the treshold of saturation being below 1200 J/m 2 . There is also a drop in the level of NAD in the epidermis protected against irradiation with a black rubber sheet. (author). 17 refs.; 6 figs.; 1 tab

Nicotinamide Phosphoribosyltransferase Upregulation by Phenylephrine Reduces Radiation Injury in Submandibular Gland

International Nuclear Information System (INIS)

Xiang, Bin; Han, Lichi; Wang, Xinyue; Tang, Ling; Li, Kailiang; Li, Xiuxiu; Zhao, Xibo; Xia, Miaomiao; Zhou, Xixi; Zhang, Fuyin; Liu, Ke Jian

2016-01-01

Purpose: Radiation therapy for head and neck cancer commonly leads to radiation sialadenitis. Emerging evidence has indicated that phenylephrine pretreatment reduces radiosensitivity in the salivary gland; however, the underlying cytoprotective mechanism remains unclear. Nicotinamide phosphoribosyltransferase (NAMPT) is not only a key enzyme for the nicotinamide adenine dinucleotide salvage pathway, but also a cytokine participating in cell survival, metabolism, and longevity, with a broad effect on cellular functions in physiology and pathology. However, the regulatory events of NAMPT in response to the irradiated salivary gland are unknown. Methods and Materials: The cell viability of primary cultured submandibular gland cells was determined using the PrestoBlue assay. NAMPT expression was measured using reverse transcriptase polymerase chain reaction and Western blotting in vitro and in vivo. Silent information regulator 1 (SIRT1) and phosphorylated Akt protein levels were examined by Western blotting. The cellular locations of NAMPT and SIRT1 were detected by immunohistochemistry. NAMPT promoter activity was assessed using the luciferase reporter gene assay. Results: NAMPT was mainly distributed in the cytoplasm of granular convoluted tubule cells and ductal cells in normal submandibular glands. mRNA and protein expression of NAMPT was downregulated after radiation but upregulated with phenylephrine pretreatment both in vivo and in vitro. Moreover, the protein expression of phosphorylated Akt and SIRT1 was decreased in irradiated glands, and phenylephrine pretreatment restored the expression of both. SIRT1 was mainly located in the cell nucleus and cytoplasm in the normal submandibular gland. Phenylephrine dramatically enhanced the expression of SIRT1, which was significantly reduced by radiation. Furthermore, phenylephrine induced a marked increase of NAMPT promoter activity. Conclusions: These findings reveal the regulatory mechanisms of NAMPT expression

Nicotinamide Phosphoribosyltransferase Upregulation by Phenylephrine Reduces Radiation Injury in Submandibular Gland

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Xiang, Bin, E-mail: xiangbin72@163.com [Laboratory of Oral and Maxillofacial Disease, Second Hospital of Dalian Medical University, Dalian (China); Han, Lichi [Department of Oral Medicine and Medical Research Center of Medical College, Dalian University, Dalian (China); Wang, Xinyue [Laboratory of Oral and Maxillofacial Disease, Second Hospital of Dalian Medical University, Dalian (China); Tang, Ling [Life Sciences and Technology College, Dalian University, Dalian (China); Li, Kailiang [Department of Oral and Maxillofacial Surgery, Second Hospital of Dalian Medical University, Dalian (China); Li, Xiuxiu [Department of Oral Medicine and Medical Research Center of Medical College, Dalian University, Dalian (China); Zhao, Xibo [Department of Oral and Maxillofacial Surgery, Second Hospital of Dalian Medical University, Dalian (China); Xia, Miaomiao [Department of Oral Medicine and Medical Research Center of Medical College, Dalian University, Dalian (China); Zhou, Xixi [Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, New Mexico (United States); Zhang, Fuyin [Department of Oral and Maxillofacial Surgery, Second Hospital of Dalian Medical University, Dalian (China); Liu, Ke Jian, E-mail: kliu@salud.unm.edu [Department of Pharmaceutical Sciences, College of Pharmacy, University of New Mexico Health Sciences Center, Albuquerque, New Mexico (United States)

2016-11-01

Purpose: Radiation therapy for head and neck cancer commonly leads to radiation sialadenitis. Emerging evidence has indicated that phenylephrine pretreatment reduces radiosensitivity in the salivary gland; however, the underlying cytoprotective mechanism remains unclear. Nicotinamide phosphoribosyltransferase (NAMPT) is not only a key enzyme for the nicotinamide adenine dinucleotide salvage pathway, but also a cytokine participating in cell survival, metabolism, and longevity, with a broad effect on cellular functions in physiology and pathology. However, the regulatory events of NAMPT in response to the irradiated salivary gland are unknown. Methods and Materials: The cell viability of primary cultured submandibular gland cells was determined using the PrestoBlue assay. NAMPT expression was measured using reverse transcriptase polymerase chain reaction and Western blotting in vitro and in vivo. Silent information regulator 1 (SIRT1) and phosphorylated Akt protein levels were examined by Western blotting. The cellular locations of NAMPT and SIRT1 were detected by immunohistochemistry. NAMPT promoter activity was assessed using the luciferase reporter gene assay. Results: NAMPT was mainly distributed in the cytoplasm of granular convoluted tubule cells and ductal cells in normal submandibular glands. mRNA and protein expression of NAMPT was downregulated after radiation but upregulated with phenylephrine pretreatment both in vivo and in vitro. Moreover, the protein expression of phosphorylated Akt and SIRT1 was decreased in irradiated glands, and phenylephrine pretreatment restored the expression of both. SIRT1 was mainly located in the cell nucleus and cytoplasm in the normal submandibular gland. Phenylephrine dramatically enhanced the expression of SIRT1, which was significantly reduced by radiation. Furthermore, phenylephrine induced a marked increase of NAMPT promoter activity. Conclusions: These findings reveal the regulatory mechanisms of NAMPT expression

Deficits in discrimination after experimental frontal brain injury are mediated by motivation and can be improved by nicotinamide administration.

Science.gov (United States)

Vonder Haar, Cole; Maass, William R; Jacobs, Eric A; Hoane, Michael R

2014-10-15

One of the largest challenges in experimental neurotrauma work is the development of models relevant to the human condition. This includes both creating similar pathophysiology as well as the generation of relevant behavioral deficits. Recent studies have shown that there is a large potential for the use of discrimination tasks in rats to detect injury-induced deficits. The literature on discrimination and TBI is still limited, however. The current study investigated motivational and motor factors that could potentially contribute to deficits in discrimination. In addition, the efficacy of a neuroprotective agent, nicotinamide, was assessed. Rats were trained on a discrimination task and motivation task, given a bilateral frontal controlled cortical impact TBI (+3.0 AP, 0.0 ML from bregma), and then reassessed. They were also assessed on motor ability and Morris water maze (MWM) performance. Experiment 1 showed that TBI resulted in large deficits in discrimination and motivation. No deficits were observed on gross motor measures; however, the vehicle group showed impairments in fine motor control. Both injured groups were impaired on the reference memory MWM, but only nicotinamide-treated rats were impaired on the working memory MWM. Nicotinamide administration improved performance on discrimination and motivation measures. Experiment 2 evaluated retraining on the discrimination task and suggested that motivation may be a large factor underlying discrimination deficits. Retrained rats improved considerably on the discrimination task. The tasks evaluated in this study demonstrate robust deficits and may improve the detection of pharmaceutical effects by being very sensitive to pervasive cognitive deficits that occur after frontal TBI.

S-Adenosyl-L-Homocysteine Hydrolase Inhibition by a Synthetic Nicotinamide Cofactor Biomimetic

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Lyn L. Kailing

2018-03-01

Full Text Available S-adenosyl-L-homocysteine (SAH hydrolases (SAHases are involved in the regulation of methylation reactions in many organisms and are thus crucial for numerous cellular functions. Consequently, their dysregulation is associated with severe health problems. The SAHase-catalyzed reaction is reversible and both directions depend on the redox activity of nicotinamide adenine dinucleotide (NAD+ as a cofactor. Therefore, nicotinamide cofactor biomimetics (NCB are a promising tool to modulate SAHase activity. In the present in vitro study, we investigated 10 synthetic truncated NAD+ analogs against a SAHase from the root-nodulating bacterium Bradyrhizobium elkanii. Among this set of analogs, one was identified to inhibit the SAHase in both directions. Isothermal titration calorimetry (ITC and crystallography experiments suggest that the inhibitory effect is not mediated by a direct interaction with the protein. Neither the apo-enzyme (i.e., deprived of the natural cofactor, nor the holo-enzyme (i.e., in the NAD+-bound state were found to bind the inhibitor. Yet, enzyme kinetics point to a non-competitive inhibition mechanism, where the inhibitor acts on both, the enzyme and enzyme-SAH complex. Based on our experimental results, we hypothesize that the NCB inhibits the enzyme via oxidation of the enzyme-bound NADH, which may be accessible through an open molecular gate, leaving the enzyme stalled in a configuration with oxidized cofactor, where the reaction intermediate can be neither converted nor released. Since the reaction mechanism of SAHase is quite uncommon, this kind of inhibition could be a viable pharmacological route, with a low risk of off-target effects. The NCB presented in this work could be used as a template for the development of more potent SAHase inhibitors.

The influence of nalidixic acid and nicotinamide of the radiation-induced cytogenetic injury to hexaploid wheat varities contrast by radioresistance

International Nuclear Information System (INIS)

Selezneva, E.M.; Sarapul'tsev, B.I.

1990-01-01

Nalidixic acid modifies the cytogenetic injury when only applied to seeds of a radiosensitive variety, Moskovskaya 35. The radioprotective effect of nicotinamide on both radiosensitive and radioresistant hexaploid wheat varities is observed being dependent on the extent which the genetic apparatus is impaired

Influence of Sodium Lauryl Sulfate and Tween 80 on Carbamazepine–Nicotinamide Cocrystal Solubility and Dissolution Behaviour

OpenAIRE

Ke Wang; Ning Qiao; Mingzhong Li

2013-01-01

The influence of the surfactants of sodium lauryl sulfate (SLS) and Tween 80 on carbamazepine–nicotinamide (CBZ–NIC) cocrystal solubility and dissolution behaviour has been studied in this work. The solubility of the CBZ–NIC cocrystal was determined by measuring the eutectic concentrations of the drug and the coformer. Evolution of the intrinsic dissolution rate (IDR) of the CBZ–NIC cocrystal was monitored by the UV imaging dissolution system during dissolution. Experimental results indicated...

Nicotinamide Improves Aspects of Healthspan, but Not Lifespan, in Mice.

Science.gov (United States)

Mitchell, Sarah J; Bernier, Michel; Aon, Miguel A; Cortassa, Sonia; Kim, Eun Young; Fang, Evandro F; Palacios, Hector H; Ali, Ahmed; Navas-Enamorado, Ignacio; Di Francesco, Andrea; Kaiser, Tamzin A; Waltz, Tyler B; Zhang, Ning; Ellis, James L; Elliott, Peter J; Frederick, David W; Bohr, Vilhelm A; Schmidt, Mark S; Brenner, Charles; Sinclair, David A; Sauve, Anthony A; Baur, Joseph A; de Cabo, Rafael

2018-03-06

The role in longevity and healthspan of nicotinamide (NAM), the physiological precursor of NAD + , is elusive. Here, we report that chronic NAM supplementation improves healthspan measures in mice without extending lifespan. Untargeted metabolite profiling of the liver and metabolic flux analysis of liver-derived cells revealed NAM-mediated improvement in glucose homeostasis in mice on a high-fat diet (HFD) that was associated with reduced hepatic steatosis and inflammation concomitant with increased glycogen deposition and flux through the pentose phosphate and glycolytic pathways. Targeted NAD metabolome analysis in liver revealed depressed expression of NAM salvage in NAM-treated mice, an effect counteracted by higher expression of de novo NAD biosynthetic enzymes. Although neither hepatic NAD + nor NADP + was boosted by NAM, acetylation of some SIRT1 targets was enhanced by NAM supplementation in a diet- and NAM dose-dependent manner. Collectively, our results show health improvement in NAM-supplemented HFD-fed mice in the absence of survival effects. Published by Elsevier Inc.

Pregnancy Increases the Renal Secretion of N1-methylnicotinamide, an Endogenous Probe for Renal Cation Transporters, in Patients Prescribed Metformin.

Science.gov (United States)

Bergagnini-Kolev, Mackenzie C; Hebert, Mary F; Easterling, Thomas R; Lin, Yvonne S

2017-03-01

N 1 -methylnicotinamide (1-NMN) has been investigated as an endogenous probe for the renal transporter activity of organic cation transporter 2 (OCT2) and multidrug and toxin extrusion proteins 1 and 2-K (MATE1 and MATE2-K). As pregnancy increased the renal secretion of metformin, a substrate for OCT2, MATE1, and MATE2-K, we hypothesized that the renal secretion of 1-NMN would be similarly affected. Blood and urine samples collected from women prescribed metformin for type 2 diabetes, gestational diabetes, and polycystic ovarian syndrome during early, mid, and late pregnancy ( n = 34 visits) and postpartum ( n = 14 visits) were analyzed for 1-NMN using liquid chromatography-mass spectrometry. The renal clearance and secretion clearance, using creatinine clearance to correct for glomerular filtration, were estimated for 1-NMN and correlated with metformin renal clearance. 1-NMN renal clearance was higher in both mid (504 ± 293 ml/min, P pregnancy (557 ± 305 ml/min, P pregnancy (269± 267, P pregnancy compared with postpartum (342 ± 283 versus 76 ± 92 ml/min, P Metformin renal clearance and 1-NMN renal clearance were positively correlated (r s = 0.68, P pregnancy due to increased glomerular filtration and net secretion by renal transporters. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

Excited-state dynamics of mononucleotides and DNA strands in a deep eutectic solvent.

Science.gov (United States)

Zhang, Yuyuan; de La Harpe, Kimberly; Hariharan, Mahesh; Kohler, Bern

2018-04-17

The photophysics of several mono- and oligonucleotides were investigated in a deep eutectic solvent for the first time. The solvent glyceline, prepared as a 1 : 2 mole ratio mixture of choline chloride and glycerol, was used to study excited-state deactivation in a non-aqueous solvent by the use of steady-state and time-resolved spectroscopy. DNA strands in glyceline retain the secondary structures that are present in aqueous solution to some degree, thus enabling a study of the effects of solvent properties on the excited states of stacked bases and stacked base pairs. The excited-state lifetime of the mononucleotide 5'-AMP in glyceline is 630 fs, or twice as long as in aqueous solution. Even slower relaxation is seen for 5'-TMP in glyceline, and a possible triplet state with a lifetime greater than 3 ns is observed. Circular dichroism spectra show that the single strand (dA)18 and the duplex d(AT)9·d(AT)9 adopt similar structures in glyceline and in aqueous solution. Despite having similar conformations in both solvents, femtosecond transient absorption experiments reveal striking changes in the dynamics. Excited-state decay and vibrational cooling generally take place more slowly in glyceline than in water. Additionally, the fraction of long-lived excited states in both oligonucleotide systems is lower in glyceline than in aqueous solution. For a DNA duplex, water is suggested to favor decay pathways involving intrastrand charge separation, while the deep eutectic solvent favors interstrand deactivation channels involving neutral species. Slower solvation dynamics in the viscous deep eutectic solvent may also play a role. These results demonstrate that the dynamics of excitations in stacked bases and stacked base pairs depend not only on conformation, but are also highly sensitive to the solvent.

Assessment the effect of NO inhibition on hippocampal normetanephrine level in stress and non-stress conditions in adult male rats

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Hana Molahoveizeh

2016-01-01

Full Text Available Background: Nitric oxide (NO has a role in the regulation of neurotransmitters release such as norepinephrine, in the hippocampus.Normetanephrine (NMN is a metabolite of norepinephrine created by action of catechol-O-methyl transferase (COMT on norepinephrine. Several studies have shown that various stresses increased release of norepinephrine and its metabolites. Therefore in the present study, the role of Nitric oxide in regulation of norepinephrine release and its metabolism was investigated by administration of L-NAME (NO synthase inhibitor in stressed and non-stressed rats. Materials and Methods: For this purpose, 50 adult rats were divided into 10 groups, of which 5 groups were exposed to restraint stress while another 5 groups were without stress. These two set of groups included intact, saline and L-NAME (20, 40, 80 mg/kg. Thirty minutes after intraperituneal injection of L-NAME, brains removed, the hippocampus dissected, weighed, homogenized and centrifuged then amount of NMN measured by ELISA kit. Results: The results showed that in non-stressed condition amount of NMN were significantly increased in group that received L-NAME (80 mg/kg in comparison with other groups but in stress condition, amount of NMN was significantly decreased in groups that received L-NAME (20,40,80 mg/kg, in comparison with control and saline groups. Comparison between stress and non-stressed groups showed that stress alone cause an increase in amount of NMN in control and saline groups. Conclusion: In conclusion, NO synthesis inhibition produced opposite responses with respect to NMN amount in the presence or absence of stress, and probably L-NAME preventing the effect of stress on increasing NMN levels mediated by nitrergic pathway.

Pnc1p-mediated nicotinamide clearance modifies the epigenetic properties of rDNA silencing in Saccharomyces cerevisiae.

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McClure, Julie M; Gallo, Christopher M; Smith, Daniel L; Matecic, Mirela; Hontz, Robert D; Buck, Stephen W; Racette, Frances G; Smith, Jeffrey S

2008-10-01

The histone deacetylase activity of Sir2p is dependent on NAD(+) and inhibited by nicotinamide (NAM). As a result, Sir2p-regulated processes in Saccharomyces cerevisiae such as silencing and replicative aging are susceptible to alterations in cellular NAD(+) and NAM levels. We have determined that high concentrations of NAM in the growth medium elevate the intracellular NAD(+) concentration through a mechanism that is partially dependent on NPT1, an important gene in the Preiss-Handler NAD(+) salvage pathway. Overexpression of the nicotinamidase, Pnc1p, prevents inhibition of Sir2p by the excess NAM while maintaining the elevated NAD(+) concentration. This growth condition alters the epigenetics of rDNA silencing, such that repression of a URA3 reporter gene located at the rDNA induces growth on media that either lacks uracil or contains 5-fluoroorotic acid (5-FOA), an unusual dual phenotype that is reminiscent of telomeric silencing (TPE) of URA3. Despite the similarities to TPE, the modified rDNA silencing phenotype does not require the SIR complex. Instead, it retains key characteristics of typical rDNA silencing, including RENT and Pol I dependence, as well as a requirement for the Preiss-Handler NAD(+) salvage pathway. Exogenous nicotinamide can therefore have negative or positive impacts on rDNA silencing, depending on the PNC1 expression level.

Effects of garlic extract on TNF-α expression and oxidative stress status in the kidneys of rats with STZ + nicotinamide-induced diabetes.

Science.gov (United States)

Ziamajidi, Nasrin; Nasiri, Abolfazl; Abbasalipourkabir, Roghayeh; Sadeghi Moheb, Somayeh

2017-12-01

Allium sativum L. (Liliaceae) (garlic) is a medicinal plant that is widely used in herbal medicine. Nephropathy is a complication of diabetes that is induced by long-term hyperglycaemia. The effects of aqueous extract of garlic (AGE) on the expression of tumour necrosis factor-alpha (TNF-α) and oxidative stress status were studied in the kidneys of rats with streptozotocin (STZ) + nicotinamide-induced diabetes. Twenty-four Wistar rats were divided into four groups: control rats, rats with STZ + nicotinamide-induced diabetes that received a single dose of STZ (65 mg/kg) and nicotinamide (110 mg/kg) intraperitoneally, diabetic rats that were treated with garlic (2 g/kg/d, gavage), and normal rats that received garlic (2 g/kg/d, gavage). The glucose level was determined in the start of study, 7 d after induction of diabetes and 33 d after treatment with garlic. At the end of the treatment period, urea, uric acid and creatinine levels were estimated in sera. Malondialdehyde (MDA), total oxidant status (TOS), nitric oxide (NO) levels and TNF-α gene and protein expression were measured in the renal tissues of the rats. The glucose, uric acid, and urea levels increased in the serum of diabetic rats compared with control rats, and decreased in garlic-treated diabetic rats compared with diabetic rats (p garlic-treated diabetic rats compared with diabetic rats (p garlic, it was close to the normal level (p garlic extract has hypoglycaemic, antioxidant and anti-inflammatory properties; therefore, it can be useful for the alleviation of diabetic complications.

A novel twist on molecular interactions between thioredoxin and nicotinamide adenine dinucleotide phosphate-dependent thioredoxin reductase

DEFF Research Database (Denmark)

Kirkensgaard, Kristine Groth; Hägglund, Per; Shahpiri, Azar

2013-01-01

The ubiquitous disulfide reductase thioredoxin (Trx) regulates several important biological processes such as seed germination in plants. Oxidized cytosolic Trx is regenerated by nicotinamide adenine dinucleotide phosphate (NADPH)-dependent thioredoxin reductase (NTR) in a multistep transfer...... dinucleotide (FAD)-binding domain of HvNTR2 to strongly affect the interaction with Trx. In particular, Trp42 and Met43 play key roles for recognition of the endogenous HvTrxh2. Trx from Arabidopsis thaliana is also efficiently recycled by HvNTR2 but turnover in this case appears to be less dependent...

Expression patterns of nicotinamide phosphoribosyltransferase and nicotinic acid phosphoribosyltransferase in human malignant lymphomas

DEFF Research Database (Denmark)

Olesen, Uffe Høgh; Hastrup, Nina; Sehested, Maxwell

2011-01-01

The purpose of the study was to determine in human malignant lymphomas the expression patterns of nicotinamide phosphoribosyltransferase (NAMPT) and nicotinic acid phosphoribosyltransferase (NAPRT), the primary, rate-limiting enzymes in the synthesis of NAD+. NAMPT is a potential biomarker...... for sensitivity to NAMPT inhibitors and NAPRT is a biomarker for the use of nicotinic acid as a chemoprotectant in treatment with NAMPT inhibitors. The NAMPT inhibitor, APO866, is currently in clinical phase II trials in lymphomas. The expression of NAMPT and NAPRT was investigated in 53 samples of malignant.......0024). In conclusion, FL are a promising target for NAMPT inhibitors whereas substantial subsets of malignant lymphomas especially in Hodgkin lymphoma may be suitable for a combination treatment with nicotinic acid and NAMPT inhibitors....

N(1)-methylnicotinamide as an endogenous probe for drug interactions by renal cation transporters: studies on the metformin-trimethoprim interaction.

Science.gov (United States)

Müller, Fabian; Pontones, Constanza A; Renner, Bertold; Mieth, Maren; Hoier, Eva; Auge, Daniel; Maas, Renke; Zolk, Oliver; Fromm, Martin F

2015-01-01

N(1)-methylnicotinamide (NMN) was proposed as an in vivo probe for drug interactions involving renal cation transporters, which, for example, transport the oral antidiabetic drug metformin, based on a study with the inhibitor pyrimethamine. The role of NMN for predicting other interactions with involvement of renal cation transporters (organic cation transporter 2, OCT2; multidrug and toxin extrusion proteins 1 and 2-K, MATE1 and MATE2-K) is unclear. We determined inhibition of metformin or NMN transport by trimethoprim using cell lines expressing OCT2, MATE1, or MATE2-K. Moreover, a randomized, open-label, two-phase crossover study was performed in 12 healthy volunteers. In each phase, 850 mg metformin hydrochloride was administered p.o. in the evening of day 4 and in the morning of day 5. In phase B, 200 mg trimethoprim was administered additionally p.o. twice daily for 5 days. Metformin pharmacokinetics and effects (measured by OGTT) and NMN pharmacokinetics were determined. Trimethoprim inhibited metformin transport with K i values of 27.2, 6.3, and 28.9 μM and NMN transport with IC50 values of 133.9, 29.1, and 0.61 μM for OCT2, MATE1, and MATE2-K, respectively. In the clinical study, trimethoprim increased metformin area under the plasma concentration-time curve (AUC) by 29.5 % and decreased metformin and NMN renal clearances by 26.4 and 19.9 %, respectively (p ≤ 0.01). Moreover, decreases of NMN and metformin renal clearances due to trimethoprim correlated significantly (r S=0.727, p=0.010). These data on the metformin-trimethoprim interaction support the potential utility of N(1)-methylnicotinamide as an endogenous probe for renal drug-drug interactions with involvement of renal cation transporters.

The Adsorption of Calmoduline via Nicotinamide Immobilized Poly(HEMA-GMA Cryogels

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Kadir Erol

2016-12-01

Full Text Available The separation and purification methods for the isolation of an important biomolecule calmoduline protein is extremely important. Among these methods, the adsorption technique is extremely popular, and the cryogels as adsorbents with the macro porous structure and interconnected flow channels cryogel they have are preferred in this field. In this study, the adsorption of calmoduline via Ca(II immobilized poly (2-hydroxyethyl methacrylate-glycidyl methacrylate, poly (HEMA-GMA, cryogels through changing interaction time, calmoduline initial concentration and temperature conditions. For the characterization of cryogels, the swelling test, Fourier Transform Infrared (FT-IR Spectroscopy, Scanning Electron Microscopy (SEM, surface area (BET, elemental analysis and ICP-OES methods were performed. Nicotinamide molecule was used as Ca (II chelating agent and the adsorption capacity of the cryogels was estimated as 1.812 mg calmoduline / g cryogel. The adsorption models of the adsorption reaction were examined by the Langmuir and Freundlich isotherm models and was determined to be more appropriate for Langmuir isotherm model.

Development of a simple and efficient method for assaying cytidine monophosphate sialic acid synthetase activity using an enzymatic reduced nicotinamide adenine dinucleotide/oxidized nicotinamide adenine dinucleotide converting system.

Science.gov (United States)

Fujita, Akiko; Sato, Chihiro; Münster-Kühnel, Anja-K; Gerardy-Schahn, Rita; Kitajima, Ken

2005-02-01

A new reliable method to assay the activity of cytidine monophosphate sialic acid (CMP-Sia) synthetase (CSS) has been developed. The activation of sialic acids (Sia) to CMP-Sia is a prerequisite for the de novo synthesis of sialoglycoconjugates. In vertebrates, CSS has been cloned from human, mouse, and rainbow trout, and the crystal structure has been resolved for the mouse enzyme. The mouse and rainbow trout enzyme have been compared with respect to substrate specificity, demonstrating that the mouse enzyme exhibits a pronounced specificity for N-acetylneuraminic acid (Neu5Ac), while the rainbow trout CSS is equally active with either of three Sia species, Neu5Ac, N-glycolylneuraminic acid (Neu5Gc), and deaminoneuraminic acid (KDN). However, molecular details that explain the pronounced substrate specificities are unknown. Understanding the catalytic mechanisms of these enzymes is of major importance, since CSSs play crucial roles in cellular sialylation patterns and thus are potential drug targets in a number of pathophysiological situations. The availability of the cDNAs and the obtained structural data enable rational approaches; however, these efforts are limited by the lack of a reliable high-throughput assay system. Here we describe a new assay system that allows product quantification in a reduced nicotinamide adenine dinucleotide (NADH)-dependent color reaction. The activation reaction catalyzed by CSS, CTP+Sia-->CMP-Sia+pyrophosphate, was evaluated by a consumption of Sia, which corresponds to that of NADH on the following two successive reactions: (i) Sia-->pyruvate+ManNAc (or Man), catalyzed by a sialic acid lyase (SAL), and (ii) pyruvate+NADH-->lactate+oxidized nicotinamide adenine dinucleotide (NAD+), catalyzed by a lactate dehydrogenase (LDH). Consumption of NADH can be photometrically monitored on a microtiter plate reader for a number of test samples at the same time. Furthermore, based on the quantification of CSS used in the SAL/LDH assay

A preclinical study on the rescue of normal tissue by nicotinic acid in high-dose treatment with APO866, a specific nicotinamide phosphoribosyltransferase inhibitor

DEFF Research Database (Denmark)

Olesen, Uffe Høgh; Thougaard, Annemette V; Jensen, Peter Buhl

2010-01-01

Inhibitor of nicotinamide phosphoribosyltransferase APO866 is a promising cancer drug currently in phase II clinical trials in oncology. Here, we present a strategy for increasing the therapeutic potential of APO866 through the rescue of normal tissues by coadministration of nicotinic acid (Vitam...

Nicotinamide Phosphoribosyltransferase in Smooth Muscle Cells Maintains Genome Integrity, Resists Aortic Medial Degeneration, and Is Suppressed in Human Thoracic Aortic Aneurysm Disease.

Science.gov (United States)

Watson, Alanna; Nong, Zengxuan; Yin, Hao; O'Neil, Caroline; Fox, Stephanie; Balint, Brittany; Guo, Linrui; Leo, Oberdan; Chu, Michael W A; Gros, Robert; Pickering, J Geoffrey

2017-06-09

The thoracic aortic wall can degenerate over time with catastrophic consequences. Vascular smooth muscle cells (SMCs) can resist and repair artery damage, but their capacities decline with age and stress. Recently, cellular production of nicotinamide adenine dinucleotide (NAD + ) via nicotinamide phosphoribosyltransferase (Nampt) has emerged as a mediator of cell vitality. However, a role for Nampt in aortic SMCs in vivo is unknown. To determine whether a Nampt-NAD + control system exists within the aortic media and is required for aortic health. Ascending aortas from patients with dilated aortopathy were immunostained for NAMPT, revealing an inverse relationship between SMC NAMPT content and aortic diameter. To determine whether a Nampt-NAD + control system in SMCs impacts aortic integrity, mice with Nampt -deficient SMCs were generated. SMC- Nampt knockout mice were viable but with mildly dilated aortas that had a 43% reduction in NAD + in the media. Infusion of angiotensin II led to aortic medial hemorrhage and dissection. SMCs were not apoptotic but displayed senescence associated-ß-galactosidase activity and upregulated p16, indicating premature senescence. Furthermore, there was evidence for oxidized DNA lesions, double-strand DNA strand breaks, and pronounced susceptibility to single-strand breakage. This was linked to suppressed poly(ADP-ribose) polymerase-1 activity and was reversible on resupplying NAD + with nicotinamide riboside. Remarkably, we discovered unrepaired DNA strand breaks in SMCs within the human ascending aorta, which were specifically enriched in SMCs with low NAMPT. NAMPT promoter analysis revealed CpG hypermethylation within the dilated human thoracic aorta and in SMCs cultured from these tissues, which inversely correlated with NAMPT expression. The aortic media depends on an intrinsic NAD + fueling system to protect against DNA damage and premature SMC senescence, with relevance to human thoracic aortopathy. © 2017 American Heart

Kinetic and thermodynamic study of the reaction catalyzed by glucose-6-phosphate dehydrogenase with nicotinamide adenine dinucleotide

International Nuclear Information System (INIS)

Martin del Campo, Julia S.; Patino, Rodrigo

2011-01-01

Research highlights: → The reaction catalyzed by one enzyme of the pentose phosphate pathway was studied. → A spectrophotometric method is proposed for kinetic and thermodynamic analysis. → The pH and the temperature influences are reported on physical chemical properties. → Relative concentrations of substrates are also important in the catalytic process. - Abstract: The enzyme glucose-6-phosphate dehydrogenase (G6PD, EC 1.1.1.49) from Leuconostoc mesenteroides has a dual coenzyme specificity with oxidized nicotinamide adenine dinucleotide (NAD ox ) and oxidized nicotinamide adenine dinucleotide phosphate as electron acceptors. The G6PD coenzyme selection is determined by the metabolic cellular prevailing conditions. In this study a kinetic and thermodynamic analysis is presented for the reaction catalyzed by G6PD from L. mesenteroides with NAD ox as coenzyme in phosphate buffer. For this work, an in situ spectrophotometric technique was employed based on the detection of one product of the reaction. Substrate and coenzyme concentrations as well as temperature and pH effects were evaluated. The apparent equilibrium constant, the Michaelis constant, and the turnover number were determined as a function of each experimental condition. The standard transformed Gibbs energy of reaction was determined from equilibrium constants at different initial conditions. For the product 6-phospho-D-glucono-1,5-lactone, a value of the standard Gibbs energy of formation is proposed, Δ f G o = -1784 ± 5 kJ mol -1 .

Kinetic and thermodynamic study of the reaction catalyzed by glucose-6-phosphate dehydrogenase with nicotinamide adenine dinucleotide

Energy Technology Data Exchange (ETDEWEB)

Martin del Campo, Julia S. [Departamento de Fisica Aplicada, Centro de Investigacion y de Estudios Avanzados - Unidad Merida, Carretera antigua a Progreso Km. 6, A.P. 73 Cordemex, 97310, Merida, Yucatan (Mexico); Patino, Rodrigo, E-mail: rtarkus@mda.cinvestav.mx [Departamento de Fisica Aplicada, Centro de Investigacion y de Estudios Avanzados - Unidad Merida, Carretera antigua a Progreso Km. 6, A.P. 73 Cordemex, 97310, Merida, Yucatan (Mexico)

2011-04-20

Research highlights: {yields} The reaction catalyzed by one enzyme of the pentose phosphate pathway was studied. {yields} A spectrophotometric method is proposed for kinetic and thermodynamic analysis. {yields} The pH and the temperature influences are reported on physical chemical properties. {yields} Relative concentrations of substrates are also important in the catalytic process. - Abstract: The enzyme glucose-6-phosphate dehydrogenase (G6PD, EC 1.1.1.49) from Leuconostoc mesenteroides has a dual coenzyme specificity with oxidized nicotinamide adenine dinucleotide (NAD{sub ox}) and oxidized nicotinamide adenine dinucleotide phosphate as electron acceptors. The G6PD coenzyme selection is determined by the metabolic cellular prevailing conditions. In this study a kinetic and thermodynamic analysis is presented for the reaction catalyzed by G6PD from L. mesenteroides with NAD{sub ox} as coenzyme in phosphate buffer. For this work, an in situ spectrophotometric technique was employed based on the detection of one product of the reaction. Substrate and coenzyme concentrations as well as temperature and pH effects were evaluated. The apparent equilibrium constant, the Michaelis constant, and the turnover number were determined as a function of each experimental condition. The standard transformed Gibbs energy of reaction was determined from equilibrium constants at different initial conditions. For the product 6-phospho-D-glucono-1,5-lactone, a value of the standard Gibbs energy of formation is proposed, {Delta}{sub f}G{sup o} = -1784 {+-} 5 kJ mol{sup -1}.

Red algae (Gelidium amansii) reduces adiposity via activation of lipolysis in rats with diabetes induced by streptozotocin-nicotinamide

OpenAIRE

Tsung-Han Yang; Hsien-Tsung Yao; Meng-Tsan Chiang

2015-01-01

Gelidium amansii (GA) is an edible red algae that is distributed mainly in northeastern Taiwan. This study was designed to investigate the effects of GA on plasma glucose, lipids, and adipocytokines in rats with streptozotocin-nicotinamide-induced diabetes. Rats were divided into four groups: (1) rats without diabetes fed a high-fat diet (control group); (2) rats with diabetes fed a high-fat diet; (3) rats with diabetes fed a high-fat diet with thiazolidinedione in the diet; and (4) rats with...

Mitochondrial respiratory complex I probed by delayed luminescence spectroscopy

Science.gov (United States)

Baran, Irina; Ionescu, Diana; Privitera, Simona; Scordino, Agata; Mocanu, Maria Magdalena; Musumeci, Francesco; Grasso, Rosaria; Gulino, Marisa; Iftime, Adrian; Tofolean, Ioana Teodora; Garaiman, Alexandru; Goicea, Alexandru; Irimia, Ruxandra; Dimancea, Alexandru; Ganea, Constanta

2013-12-01

The role of mitochondrial complex I in ultraweak photon-induced delayed photon emission [delayed luminescence (DL)] of human leukemia Jurkat T cells was probed by using complex I targeting agents like rotenone, menadione, and quercetin. Rotenone, a complex I-specific inhibitor, dose-dependently increased the mitochondrial level of reduced nicotinamide adenine dinucleotide (NADH), decreased clonogenic survival, and induced apoptosis. A strong correlation was found between the mitochondrial levels of NADH and oxidized flavin mononucleotide (FMNox) in rotenone-, menadione- and quercetin-treated cells. Rotenone enhanced DL dose-dependently, whereas quercetin and menadione inhibited DL as well as NADH or FMNox. Collectively, the data suggest that DL of Jurkat cells originates mainly from mitochondrial complex I, which functions predominantly as a dimer and less frequently as a tetramer. In individual monomers, both pairs of pyridine nucleotide (NADH/reduced nicotinamide adenine dinucleotide phosphate) sites and flavin (FMN-a/FMN-b) sites appear to bind cooperatively their specific ligands. Enhancement of delayed red-light emission by rotenone suggests that the mean time for one-electron reduction of ubiquinone or FMN-a by the terminal Fe/S center (N2) is 20 or 284 μs, respectively. All these findings suggest that DL spectroscopy could be used as a reliable, sensitive, and robust technique to probe electron flow within complex I in situ.

Restoration of Mitochondrial NAD+ Levels Delays Stem Cell Senescence and Facilitates Reprogramming of Aged Somatic Cells.

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Son, Myung Jin; Kwon, Youjeong; Son, Taekwon; Cho, Yee Sook

2016-12-01

The fundamental tenet that aging is irreversible has been challenged by the development of reprogramming technology that can restore molecular and cellular age by reversing the progression of aging. The use of cells from aged individuals as sources for reprogramming or transplantation creates a major barrier in stem cell therapy with respect to cell quality and quantity. Here, we investigated the molecular features underlying senescence and rejuvenation during aged cell reprogramming and identified novel factors that can overcome age-associated barriers. Enzymes, such as nicotinamide nucleotide transhydrogenase (NNT) and nicotinamide mononucleotide adenylyltransferase 3 (NMNAT3), that control mitochondrial NAD + levels appear to be susceptible to aging. In aged cells, mitochondrial NAD + levels decrease, accompanied by reduced SIRT3 activity; these changes severely impede cell fate transition. However, in cells collected from aged p16 knockout mice, which exhibit delayed cellular senescence, no changes in NNT or NMNAT3 expression were found. Importantly, restoring mitochondrial NAD + levels by overexpressing NNT and NMNAT3 enhanced reprogramming efficiency of aged somatic cells and extended the lifespan of human mesenchymal stem cells by delaying replicative senescence. These results demonstrate that maintenance of mitochondrial NAD + levels is critical for reversing the mechanisms of aging and ensuring that cells collected from aged individuals are of high quality. Stem Cells 2016;34:2840-2851. © 2016 AlphaMed Press.

Combination of hydrotropic nicotinamide with nanoparticles for enhancing tacrolimus percutaneous delivery

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Pan W

2016-08-01

Full Text Available Wenhui Pan, Mengyao Qin, Guoguang Zhang, Yueming Long, Wenyi Ruan, Jingtong Pan, Zushuai Wu, Tao Wan, Chuanbin Wu, Yuehong Xu Department of Pharmaceutics, School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou, People’s Republic of China Abstract: Tacrolimus (FK506, an effective immunosuppressant for treating inflammatory skin diseases, hardly penetrates into and through the skin owing to its high hydrophobicity and molecular weight. The aim of this study was to develop a hybrid system based on nicotinamide (NIC and nanoparticles (NPs encapsulating FK506, such as FK506–NPs–NIC, for facilitating percutaneous delivery, which exploited virtues of both NIC and NPs to obtain the synergetic effect. Solubility and percutaneous permeation studies were carried out. The results showed that NIC could increase the solubility and permeability of FK506 and that 20% (w/v NIC presented higher FK506 permeability and was thus chosen as the hydrotropic solution to solubilize FK506 and prepare FK506–NPs–NIC. Hyaluronic acid (HA was chemically conjugated with cholesterol (Chol to obtain amphiphilic conjugate of HA–Chol, which self-assembled NPs in 20% NIC solution containing FK506. The particle size, zeta potential, and morphology of NPs were characterized. The encapsulation efficiency and in vitro percutaneous permeation of NPs were evaluated in the presence and absence of NIC. The results demonstrated that hydrotropic solubilizing FK506 was readily encapsulated into NPs with a higher encapsulation efficiency of 79.2%±4.2%, and the combination of NPs with NIC exhibited a significantly synergistic effect on FK506 deposition within the skin (2.39±0.53 µg/cm2 and penetration through the skin (13.38±2.26 µg/cm2. The effect of the combination of NPs with NIC on drug permeation was further visualized by confocal laser scanning microscope through in vivo permeation studies, and the results confirmed that NPs–NIC synergistically enhanced

Enzymatic synthesis of 13N-β-nicotinamide adenine dinucleotide

International Nuclear Information System (INIS)

Lambrecht, R.H.D.; Slegers, G.; Claeys, A.; Vandecasteele, C.

1985-01-01

Nitrogen-13-labelled β-nicotinamide adenine dinucleotide ( 13 N-NAD) is an interesting new compound for positron emission tomography. A semi-automatic production method is developed that yields a solution of 13 N-NAD of radiopharmaceutical quality, suitable for human intravenous administration. The 13 N-NAD is prepared enzymatically in one step from cyclotron-produced 13 NH 3 and nicotinic acid adenine dinucleotide (deamido-NAD). The enzyme NAD synthetase (E.C. 6.3.1.5), catalysing this reaction, is extracted and purified from Escherichia coli. The purified enzyme is immobilized by glutaraldehyde coupling to γ-aminopropylsilane-coated porous glass beads. The enzyme-loaded glass beads are packed in a column. The kinetic properties of the column are optimized. For synthetizing 13 N-NAD, the mixture of co-factors and substrates, containing 13 NH 3 , is pumped over the enzyme column. The unreacted 13 NH 3 is separated from 13 N-NAD by on-line passage over a cation exchanger. After passing over a millipore filter, a sterile solution of radiochemically pure 13 N-NAD is obtained, containing 70 mCi in 10 mL. The total synthesis time is 10 minutes. The specific activity is about 120 mCi/μmol at EOB. Quality control includes sterility and pyrogen tests, HPLC and HPTLC analysis. (author)

Estuarine monitoring programs in the Albemarle Sound study area, North Carolina

Science.gov (United States)

Moorman, Michelle; Kolb, Katharine R.; Supak, Stacy

2014-01-01

Albemarle Sound was selected in 2012 as one of the two demonstration sites in the Nation to test and improve the design of the National Water Quality Monitoring Council’s National Monitoring Network (NMN) for U.S. Coastal Waters and their tributaries. The goal of the NMN for U.S. coastal waters and tributaries is to provide information about the health of our oceans and coastal ecosystems and inland influences on coastal waters for improved resource management. The NMN is an integrated, multidisciplinary, and multiorganizational program using multiple sources of data and information to augment current monitoring programs.

Two for the Price of One: A Neuroprotective Chaperone Kit within NAD Synthase Protein NMNAT2.

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Angela Lavado-Roldán

2016-07-01

Full Text Available One of the most fascinating properties of the brain is the ability to function smoothly across decades of a lifespan. Neurons are nondividing mature cells specialized in fast electrical and chemical communication at synapses. Often, neurons and synapses operate at high levels of activity through sophisticated arborizations of long axons and dendrites that nevertheless stay healthy throughout years. On the other hand, aging and activity-dependent stress strike onto the protein machineries turning proteins unfolded and prone to form pathological aggregates associated with neurodegeneration. How do neurons protect from those insults and remain healthy for their whole life? Ali and colleagues now present a molecular mechanism by which the enzyme nicotinamide mononucleotide adenylyltransferase 2 (NMNAT2 acts not only as a NAD synthase involved in axonal maintenance but as a molecular chaperone helping neurons to overcome protein unfolding and protein aggregation.

Hydrotropic solubilization of lipophilic drugs for oral delivery: The effects of urea and nicotinamide on carbamazepine solubility-permeability interplay

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Avital Beig

2016-10-01

Full Text Available Hydrotropy refers to increasing the water solubility of otherwise poorly soluble compound by the presence of small organic molecules. While it can certainly increase the apparent solubility of a lipophilic drug, the effect of hydrotropy on the drugs' permeation through the intestinal membrane has not been studied. The purpose of this work was to investigate the solubility-permeability interplay when using hydrotropic drug solubilization. The concentration-dependent effects of the commonly used hydrotropes urea and nicotinamide, on the solubility and the permeability of the lipophilic antiepileptic drug carbamazepine were studied. Then, the solubility-permeability interplay was mathematically modeled, and was compared to the experimental data. Both hydrotropes allowed significant concentration-dependent carbamazepine solubility increase (up to ~30-fold. A concomitant permeability decrease was evident both in-vitro and in-vivo (~17-fold for nicotinamide and ~9-fold for urea, revealing a solubility-permeability tradeoff when using hydrotropic drug solubilization. A relatively simplified simulation approach based on proportional opposite correlation between the solubility increase and the permeability decrease at a given hydrotrope concentration allowed excellent prediction of the overall solubility-permeability tradeoff. In conclusion, when using hydrotropic drug solubilization it is prudent to not focus solely on solubility, but to account for the permeability as well; achieving optimal solubility-permeability balance may promote the overall goal of the formulation to maximize oral drug exposure.

Hydrotropic Solubilization of Lipophilic Drugs for Oral Delivery: The Effects of Urea and Nicotinamide on Carbamazepine Solubility–Permeability Interplay

Science.gov (United States)

Beig, Avital; Lindley, David; Miller, Jonathan M.; Agbaria, Riad; Dahan, Arik

2016-01-01

Hydrotropy refers to increasing the water solubility of otherwise poorly soluble compound by the presence of small organic molecules. While it can certainly increase the apparent solubility of a lipophilic drug, the effect of hydrotropy on the drugs’ permeation through the intestinal membrane has not been studied. The purpose of this work was to investigate the solubility–permeability interplay when using hydrotropic drug solubilization. The concentration-dependent effects of the commonly used hydrotropes urea and nicotinamide, on the solubility and the permeability of the lipophilic antiepileptic drug carbamazepine were studied. Then, the solubility–permeability interplay was mathematically modeled, and was compared to the experimental data. Both hydrotropes allowed significant concentration-dependent carbamazepine solubility increase (up to ∼30-fold). A concomitant permeability decrease was evident both in vitro and in vivo (∼17-fold for nicotinamide and ∼9-fold for urea), revealing a solubility–permeability tradeoff when using hydrotropic drug solubilization. A relatively simplified simulation approach based on proportional opposite correlation between the solubility increase and the permeability decrease at a given hydrotrope concentration allowed excellent prediction of the overall solubility–permeability tradeoff. In conclusion, when using hydrotropic drug solubilization it is prudent to not focus solely on solubility, but to account for the permeability as well; achieving optimal solubility–permeability balance may promote the overall goal of the formulation to maximize oral drug exposure. PMID:27826241

Flavin mononucleotide (FMN)-based fluorescent protein (FbFP) as reporter for gene expression in the anaerobe Bacteroides fragilis.

Science.gov (United States)

Lobo, Leandro A; Smith, Charles J; Rocha, Edson R

2011-04-01

In this study, we show the expression of flavin mononucleotide-based fluorescent protein (FbFP) BS2 as a marker for gene expression in the opportunistic human anaerobic pathogen Bacteroides fragilis. Bacteroides fragilis 638R strain carrying osu∷bs2 constructs showed inducible fluorescence following addition of maltose anaerobically compared with nonfluorescent cells under glucose-repressed conditions. Bacteria carrying ahpC∷bs2 or dps∷bs2 constructs were fluorescent following induction by oxygen compared with nonfluorescent cells from the anaerobic control cultures. In addition, when these transcriptional fusion constructs were mobilized into B. fragilis IB263, a constitutive peroxide response strain, fluorescent BS2, was detected in both anaerobic and aerobic cultures, confirming the unique properties of the FbFP BS2 to yield fluorescent signal in B. fragilis in the presence and in the absence of oxygen. Moreover, intracellular expression of BS2 was also detected when cell culture monolayers of J774.1 macrophages were incubated with B. fragilis ahpC∷bs2 or dps∷bs2 strains within an anaerobic chamber. This suggests that ahpC and dps are induced following internalization by macrophages. Thus, we show that BS2 is a suitable tool for the detection of gene expression in obligate anaerobic bacteria in in vivo studies. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Diaquabis(4-bromobenzoato-κObis(nicotinamide-κN1copper(II

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Hacali Necefoğlu

2011-07-01

Full Text Available The asymmetric unit of the title mononuclear CuII complex, [Cu(C7H4BrO22(C6H6N2O2(H2O2], contains one half-molecule, the CuII atom being located on an inversion center. The unit cell contains two nicotinamide (NA, two 4-bromobenzoate (PBB ligands and two coordinated water molecules. The four O atoms in the equatorial plane around the CuII ion form a slightly distorted square-planar arrangement, while the slightly distorted octahedral coordination is completed by the two N atoms of the NA ligands in the axial positions. The dihedral angle between the carboxylate group and the adjacent benzene ring is 22.17 (16°, while the pyridine ring and the benzene ring are oriented at a dihedral angle of 82.80 (6°. In the crystal, N—H...O, O—H...O and C—H...O hydrogen bonds link the molecules into a three-dimensional network. A weak C—H...π interaction is also observed.

The kinetic analysis of the N-methylation of 4-phenylpyridine by nicotinamide N-methyltransferase: Evidence for a novel mechanism of substrate inhibition.

Science.gov (United States)

van Haren, Matthijs J; Thomas, Martin G; Sartini, Davide; Barlow, David J; Ramsden, David B; Emanuelli, Monica; Klamt, Fábio; Martin, Nathaniel I; Parsons, Richard B

2018-03-13

The N-methylation of 4-phenylpyridine produces the neurotoxin 1-methyl-4-phenylpyridinium ion (MPP+). We investigated the kinetics of 4-phenylpyridine N-methylation by nicotinamide N-methyltransferase (NNMT) and its effect upon 4-phenylpyridine toxicity in vitro. Human recombinant NNMT possessed 4-phenylpyridine N-methyltransferase activity, with a specific activity of 1.7 ± 0.03 nmol MPP+ produced/h/mg NNMT. Although the K m for 4-phenylpyridine was similar to that reported for nicotinamide, its k cat of 9.3 × 10 -5  ± 2 × 10 -5  s -1 and specificity constant, k cat /K m , of 0.8 ± 0.8 s -1  M -1 were less than 0.15% of the respective values for nicotinamide, demonstrating that 4-phenylpyridine is a poor substrate for NNMT. At low (N-methylation was competitively inhibited by dimethylsulphoxide, with a K i of 34 ± 8 mM. At high (>2.5 mM) substrate concentration, enzyme activity followed substrate inhibition kinetics, with a K i of 4 ± 1 mM. In silico molecular docking suggested that 4-phenylpyridine binds to the active site of NNMT in two non-redundant poses, one a substrate binding mode and the other an inhibitory mode. Finally, the expression of NNMT in the SH-SY5Y cell-line had no effect cell death, viability, ATP content or mitochondrial membrane potential. These data demonstrate that 4-phenylpyridine N-methylation by NNMT is unlikely to serve as a source of MPP+. The possibility for competitive inhibition by dimethylsulphoxide should be considered in NNMT-based drug discovery studies. The potential for 4-phenylpyridine to bind to the active site in two binding orientations using the same active site residues is a novel mechanism of substrate inhibition. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effects of a wide range of dietary nicotinamide riboside (NR) concentrations on metabolic flexibility and white adipose tissue (WAT) of mice fed a mildly obesogenic diet

NARCIS (Netherlands)

Shi, W.; Hegeman, M.A.; Dartel, van D.A.M.; Tang, J.; Suarez, M.; Swarts, H.; Hee, van der B.; Arola, L.; Keijer, J.

2017-01-01

Scope: Metabolic flexibility is the ability to switch metabolism between carbohydrate oxidation (CHO) and fatty acid oxidation (FAO) and is a biomarker for metabolic health. The effect on metabolic health of nicotinamide riboside (NR) as an exclusive source of vitamin B3 is unknown and is examined

Modulatory effects of garlic, ginger, turmeric and their mixture on hyperglycaemia, dyslipidaemia and oxidative stress in streptozotocin-nicotinamide diabetic rats.

Science.gov (United States)

Madkor, Hafez R; Mansour, Sherif W; Ramadan, Gamal

2011-04-01

Spices which show hypoglycaemic, hypolipidaemic and antioxidant activities may have a role in the treatment of diabetes and its complications. The present study aimed to compare the modulatory effects of garlic, ginger, turmeric and their mixture on the metabolic syndrome and oxidative stress in streptozotocin (STZ)-nicotinamide diabetic rats. Diabetes was induced in overnight fasted rats by a single intraperitoneal injection of STZ (65 mg/kg body weight) and nicotinamide (110 mg/kg body weight, 15 min before STZ injection). Diabetic rats orally received either distilled water (as vehicle) or 200 mg/kg body weight of garlic bulb, ginger rhizome or turmeric rhizome powder suspension separately or mixed together (GGT mixture) for twenty-eight consecutive days. The results showed that these spices and their mixture significantly alleviated (80-97 %, P diabetic rats by increasing the production of insulin (26-37 %), enhancing the antioxidant defence system (31-52 %, especially GSH) and decreasing lipid peroxidation (60-97 %). The greatest modulation was seen in diabetic rats that received garlic and the GGT mixture (10-23 % more than that in the ginger and turmeric groups). In conclusion, garlic or the mix including garlic appears to have an impact on each of the measures more effectively than ginger and turmeric and may have a role in alleviating the risks of the metabolic syndrome and cardiovascular complications.

Blue light induced reactive oxygen species from flavin mononucleotide and flavin adenine dinucleotide on lethality of HeLa cells.

Science.gov (United States)

Yang, Ming-Yeh; Chang, Chih-Jui; Chen, Liang-Yü

2017-08-01

Photodynamic therapy (PDT) is a safe and non-invasive treatment for cancers and microbial infections. Various photosensitizers and light sources have been developed for clinical cancer therapies. Flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) are the cofactor of enzymes and are used as photosensitizers in this study. Targeting hypoxia and light-triggering reactive oxygen species (ROS) are experimental strategies for poisoning tumor cells in vitro. HeLa cells are committed to apoptosis when treated with FMN or FAD and exposed to visible blue light (the maximum emitted wavelength of blue light is 462nm). Under blue light irradiation at 3.744J/cm 2 (=0.52mW/cm 2 irradiated for 2h), the minimal lethal dose is 3.125μM and the median lethal doses (LD 50 ) for FMN and FAD are 6.5μM and 7.2μM, respectively. Individual exposure to visible blue light irradiation or riboflavin photosensitizers does not produce cytotoxicity and no side effects are observed in this study. The western blotting results also show that an intrinsic apoptosis pathway is activated by the ROS during photolysis of riboflavin analogues. Blue light triggers the cytotoxicity of riboflavins on HeLa cells in vitro. Based on these results, this is a feasible and efficient of PDT with an intrinsic photosensitizer for cancer research. Copyright © 2017 Elsevier B.V. All rights reserved.

The role of urinary fractionated metanephrines in the diagnosis of phaeochromocytoma

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Kanakamani Jeyaraman

2013-01-01

Full Text Available Background & objectives: Plasma and urinary metanephrines are used as screening tests for the diagnosis of phaeochromocytoma. The recommended cut-off levels are not standardized. This study was conducted to identify a cut-off level for 24 h urinary fractionated metanephrines viz. metanephrine (uMN and normetanephrine (uNMN using enzyme immunoassay for the diagnosis of phaeochromocytoma. Methods: Consecutive patients suspected to have phaeochromocytoma were included in the study. uMN and uNMN in 24 h urinary sample were measured using a commercial ELISA kit. Results: Overall, 72 patients were included over a period of 18 months. Twenty patients had histopathologically confirmed phaeochromocytoma and in 52 patients phaeochromocytoma was ruled out. Using the upper limit of normal stated by the assay manufacturer as the cut-off, uMN >350 μg/day had a low sensitivity and uNMN >600 μg/day had a poor specificity. By increasing the cut-off value of uNMN to twice the upper limit, specificity increased significantly without much loss in sensitivity. Combining uMN and uNMN using a cut-off twice the upper limit improved the diagnostic performance - sensitivity (95%; specificity (92.3%; positive predictive value (PPV - 82.6%; negative predictive value (NPV - 98%. In subsets of patients with a variable pretest probability for phaeochromocytoma, the PPV correlates well with the occurred of these tumors decreased, while the NPV remained at 100 per cent. Interpretation & conclusions: ELISA is a simple and reliable method for measuring uMN and uNMN. The test has a good NPV and can be used as an initial screening test for ruling out phaeochromocytoma. Each hospital will have to define the cut-off value for the assay being used, choosing a proper control population.

The generation of myricetin-nicotinamide nanococrystals by top down and bottom up technologies.

Science.gov (United States)

Liu, Mingyu; Hong, Chao; Li, Guowen; Ma, Ping; Xie, Yan

2016-09-30

Myricetin-nicotinamide (MYR-NIC) nanococrystal preparation methods were developed and optimized using both top down and bottom up approaches. The grinding (top down) method successfully achieved nanococrystals, but there were some micrometer range particles and aggregation. The key consideration of the grinding technology was to control the milling time to determine a balance between the particle size and distribution. In contrast, a modified bottom up approach based on a solution method in conjunction with sonochemistry resulted in a uniform MYR-NIC nanococrystal that was confirmed by powder x-ray diffraction, scanning electron microscopy, dynamic light scattering, and differential scanning calorimeter, and the particle dissolution rate and amount were significantly greater than that of MYR-NIC cocrystal. Notably, this was a simple method without the addition of any non-solvent. We anticipate our findings will provide some guidance for future nanococrystal preparation as well as its application in both chemical and pharmaceutical area.

The reported human NADsyn2 is ammonia-dependent NAD synthetase from a pseudomonad.

Science.gov (United States)

Bieganowski, Pawel; Brenner, Charles

2003-08-29

Nicotinamide-adenine dinucleotide (NAD+) synthetases catalyze the last step in NAD+ metabolism in the de novo, import, and salvage pathways that originate from tryptophan (or aspartic acid), nicotinic acid, and nicotinamide, respectively, and converge on nicotinic acid mononucleotide. NAD+ synthetase converts nicotinic acid adenine dinucleotide to NAD+ via an adenylylated intermediate. All of the known eukaryotic NAD+ synthetases are glutamine-dependent, hydrolyzing glutamine to glutamic acid to provide the attacking ammonia. In the prokaryotic world, some NAD+ synthetases are glutamine-dependent, whereas others can only use ammonia. Earlier, we noted a perfect correlation between presence of a domain related to nitrilase and glutamine dependence and then proved in the accompanying paper (Bieganowski, P., Pace, H. C., and Brenner, C. (2003) J. Biol. Chem. 278, 33049-33055) that the nitrilase-related domain is an essential, obligate intramolecular, thiol-dependent glutamine amidotransferase in the yeast NAD+ synthetase, Qns1. Independently, human NAD+ synthetase was cloned and shown to depend on Cys-175 for glutamine-dependent but not ammonia-dependent NAD+ synthetase activity. Additionally, it was claimed that a 275 amino acid open reading frame putatively amplified from human glioma cell line LN229 encodes a human ammonia-dependent NAD+ synthetase and this was speculated largely to mediate NAD+ synthesis in human muscle tissues. Here we establish that the so-called NADsyn2 is simply ammonia-dependent NAD+ synthetase from Pseudomonas, which is encoded on an operon with nicotinic acid phosphoribosyltransferase and, in some Pseudomonads, with nicotinamidase.

Vibrio Phage KVP40 Encodes a Functional NAD+ Salvage Pathway.

Science.gov (United States)

Lee, Jae Yun; Li, Zhiqun; Miller, Eric S

2017-05-01

The genome of T4-type Vibrio bacteriophage KVP40 has five genes predicted to encode proteins of pyridine nucleotide metabolism, of which two, nadV and natV , would suffice for an NAD + salvage pathway. NadV is an apparent nicotinamide phosphoribosyltransferase (NAmPRTase), and NatV is an apparent bifunctional nicotinamide mononucleotide adenylyltransferase (NMNATase) and nicotinamide-adenine dinucleotide pyrophosphatase (Nudix hydrolase). Genes encoding the predicted salvage pathway were cloned and expressed in Escherichia coli , the proteins were purified, and their enzymatic properties were examined. KVP40 NadV NAmPRTase is active in vitro , and a clone complements a Salmonella mutant defective in both the bacterial de novo and salvage pathways. Similar to other NAmPRTases, the KVP40 enzyme displayed ATPase activity indicative of energy coupling in the reaction mechanism. The NatV NMNATase activity was measured in a coupled reaction system demonstrating NAD + biosynthesis from nicotinamide, phosphoribosyl pyrophosphate, and ATP. The NatV Nudix hydrolase domain was also shown to be active, with preferred substrates of ADP-ribose, NAD + , and NADH. Expression analysis using reverse transcription-quantitative PCR (qRT-PCR) and enzyme assays of infected Vibrio parahaemolyticus cells demonstrated nadV and natV transcription during the early and delayed-early periods of infection when other KVP40 genes of nucleotide precursor metabolism are expressed. The distribution and phylogeny of NadV and NatV proteins among several large double-stranded DNA (dsDNA) myophages, and also those from some very large siphophages, suggest broad relevance of pyridine nucleotide scavenging in virus-infected cells. NAD + biosynthesis presents another important metabolic resource control point by large, rapidly replicating dsDNA bacteriophages. IMPORTANCE T4-type bacteriophages enhance DNA precursor synthesis through reductive reactions that use NADH/NADPH as the electron donor and NAD

Influence of Sodium Lauryl Sulfate and Tween 80 on Carbamazepine–Nicotinamide Cocrystal Solubility and Dissolution Behaviour

Science.gov (United States)

Li, Mingzhong; Qiao, Ning; Wang, Ke

2013-01-01

The influence of the surfactants of sodium lauryl sulfate (SLS) and Tween 80 on carbamazepine–nicotinamide (CBZ–NIC) cocrystal solubility and dissolution behaviour has been studied in this work. The solubility of the CBZ–NIC cocrystal was determined by measuring the eutectic concentrations of the drug and the coformer. Evolution of the intrinsic dissolution rate (IDR) of the CBZ–NIC cocrystal was monitored by the UV imaging dissolution system during dissolution. Experimental results indicated that SLS and Tween 80 had little influence upon the solubility of the CBZ–NIC cocrystal but they had totally opposite effects on the IDR of the CBZ–NIC cocrystal during dissolution. SLS significantly increased the IDR of the CBZ–NIC cocrystal while Tween 80 decreased its IDR. PMID:24300560

Influence of Sodium Lauryl Sulfate and Tween 80 on Carbamazepine–Nicotinamide Cocrystal Solubility and Dissolution Behaviour

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Ke Wang

2013-10-01

Full Text Available The influence of the surfactants of sodium lauryl sulfate (SLS and Tween 80 on carbamazepine–nicotinamide (CBZ–NIC cocrystal solubility and dissolution behaviour has been studied in this work. The solubility of the CBZ–NIC cocrystal was determined by measuring the eutectic concentrations of the drug and the coformer. Evolution of the intrinsic dissolution rate (IDR of the CBZ–NIC cocrystal was monitored by the UV imaging dissolution system during dissolution. Experimental results indicated that SLS and Tween 80 had little influence upon the solubility of the CBZ–NIC cocrystal but they had totally opposite effects on the IDR of the CBZ–NIC cocrystal during dissolution. SLS significantly increased the IDR of the CBZ–NIC cocrystal while Tween 80 decreased its IDR.

Influence of sodium lauryl sulfate and tween 80 on carbamazepine-nicotinamide cocrystal solubility and dissolution behaviour.

Science.gov (United States)

Li, Mingzhong; Qiao, Ning; Wang, Ke

2013-10-11

The influence of the surfactants of sodium lauryl sulfate (SLS) and Tween 80 on carbamazepine-nicotinamide (CBZ-NIC) cocrystal solubility and dissolution behaviour has been studied in this work. The solubility of the CBZ-NIC cocrystal was determined by measuring the eutectic concentrations of the drug and the coformer. Evolution of the intrinsic dissolution rate (IDR) of the CBZ-NIC cocrystal was monitored by the UV imaging dissolution system during dissolution. Experimental results indicated that SLS and Tween 80 had little influence upon the solubility of the CBZ-NIC cocrystal but they had totally opposite effects on the IDR of the CBZ-NIC cocrystal during dissolution. SLS significantly increased the IDR of the CBZ-NIC cocrystal while Tween 80 decreased its IDR.

Nicotinamide starvation and inhibition of poly(ADP-Ribose) synthesis enhance the induced mutation in Chinese hamster V79 cells

International Nuclear Information System (INIS)

Okada, Gensaku; Kaneko, Ichiro; Mitsui, Hideki.

1987-01-01

The effects of nicotinamide (NA) deficiency and added NA and 3-aminobenzamide (3AB) on the cytotoxicity and the induction of mutations in Chinese hamster V79-14 cells were investigated. In NA deficiency the addition of NA (up to 4 mM) and 3AB (up to 7.5 mM) was not cytotoxic. The presence of NA prior to exposure to mitomycin C (MMC) or γ-rays produced a dose-dependent increase in the relative cloning ability of DNA-damaged cells. The lethality of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) was significantly potentiated by pre-treatment with 5 mM 3AB, but no potentiation by 3AB was observed for MMC, ultraviolet (UV)-B light, or γ-rays. Among cells pre-cultured in NA-free medium there were increased frequencies of mutations at both the hypoxanthineguanine phosphoribosyltransferase (HGPRT) and the adenine phosphoribosyltransferase (APRT) loci following DNA damage. The enhancing effect by NA deficiency was time-dependent. Incubation with NA prior to DNA damage produced a significant reduction in the frequency of mutations. The addition of 3AB to the nicotinamide adenine dinucleotide (NAD + )-depleted cell cultures before or after the DNA damage also strongly increased the frequency of induced mutations, with increasing concentrations of 3AB up to 5 mM, but the frequency was reduced at higher concentrations. The interaction between NA deficiency and the addition of 3AB appears to act synergistically on mutation induction. A correlation was observed between the potential of inhibiting poly (ADP-ribose) polymerase and the enhancement of mutation frequency. (author)

Immunoassays for riboflavin and flavin mononucleotide using antibodies specific to d-ribitol and d-ribitol-5-phosphate.

Science.gov (United States)

Ravi, G; Venkatesh, Yeldur P

2017-06-01

Riboflavin (vitamin B 2 ), a water-soluble vitamin, plays a key role in maintaining human health. Though, numerous methods have been reported for the determination of total riboflavin (TRF) content in foods and biological samples, very few methods are reported for quantifying riboflavin and its coenzymes [flavin mononucleotide (FMN); flavin adenine dinucleotide (FAD)] individually. Recently, we have demonstrated that antibodies specific to d-ribitol and d-ribitol-5-phosphate also recognize riboflavin and FMN, respectively, and not vice-versa. In this study, we have evaluated these two antibodies for the analysis of riboflavin and FMN by indirect competitive ELISA (icELISA) in selected foods and pharmaceuticals. Under the optimal assay conditions, 50% inhibition concentration (IC 50 ) and limit of detection (LOD, IC 10 ) were 3.41ng/mL and 0.02ng/mL for riboflavin, and 7.84ng/mL and 0.24ng/mL for FMN, respectively, with detectable concentration range between 0.1 and 100ng of analytes and riboflavin and FMN) from the same food samples showed variation in their values compared to TRF, and were in good agreement with values obtained from HPLC and AOAC methods. Further, spiking and recovery analysis of food samples and pharmaceuticals showed no significant matrix effects. The immunoassays were validated in terms of accuracy and precision using inter- and intra-assays. The immunoassays developed in this study are sensitive and appears feasible for screening a large number of samples in the quantification of riboflavin and FMN in various biological samples, pharmaceuticals and natural/processed foods. Copyright © 2017 Elsevier B.V. All rights reserved.

Acute Toxicity Profile and Compliance to Accelerated Radiotherapy Plus Carbogen and Nicotinamide for Clinical Stage T2–4 Laryngeal Cancer: Results of a Phase III Randomized Trial

International Nuclear Information System (INIS)

Janssens, Geert O.; Terhaard, Chris H.; Doornaert, Patricia A.; Bijl, Hendrik P.; Ende, Piet van den; Chin, Alim; Pop, Lucas A.; Kaanders, Johannes H.

2012-01-01

Purpose: To report the acute toxicity profile and compliance from a randomized Phase III trial comparing accelerated radiotherapy (AR) with accelerated radiotherapy plus carbogen and nicotinamide (ARCON) in laryngeal cancer. Methods and Materials: From April 2001 to February 2008, 345 patients with cT2–4 squamous cell laryngeal cancer were randomized to AR (n = 174) and ARCON (n = 171). Acute toxicity was scored weekly until Week 8 and every 2–4 weeks thereafter. Compliance to carbogen and nicotinamide was reported. Results: Between both treatment arms (AR vs. ARCON) no statistically significant difference was observed for incidence of acute skin reactions (moist desquamation: 56% vs. 58%, p = 0.80), acute mucosal reactions (confluent mucositis: 79% vs. 85%, p = 0.14), and symptoms related to acute mucositis (severe pain on swallowing: 53% vs. 58%, p = 0.37; nasogastric tube feeding: 28% vs. 28%, p = 0.98; narcotic medicines required: 58% vs. 58%, p = 0.97). There was a statistically significant difference in median duration of confluent mucositis in favor of AR (2.0 vs 3.0 weeks, p = 0.01). There was full compliance with carbogen breathing and nicotinamide in 86% and 80% of the patients, with discontinuation in 6% and 12%, respectively. Adjustment of antiemesis prophylaxis was needed in 42% of patients. Conclusion: With the exception of a slight increase in median duration of acute confluent mucositis, the present data reveal a similar acute toxicity profile between both regimens and a good compliance with ARCON for clinical stage T2–4 laryngeal cancers. Treatment outcome and late morbidity will determine the real therapeutic benefit.

Effects of Hydro-alcoholic Extract from Arctium lappa L. (Burdock) Root on Gonadotropins, Testosterone, and Sperm Count and Viability in Male Mice with Nicotinamide/ Streptozotocin-Induced Type 2 Diabetes.

Science.gov (United States)

Ahangarpour, Akram; Oroojan, Ali Akbar; Heidari, Hamid; Ghaedi, Ehsan; Taherkhani, Reza

2015-01-01

Reproductive dysfunction is a complication of diabetes. Arctium lappa (burdock) root has hypoglycemic and antioxidative properties, which are traditionally used for treatment of impotence and sterility. Therefore, the aim of this study is to investigate the effects of its hydro alcoholic extract on gonadotropin, testosterone, and sperm parameters in nicotinamide/ streptozotocin-induced diabetic mice. In this experimental study, 56 adult male Naval Medical Research Institute (NMRI) mice (30-35 g) were randomly divided into seven groups: control, diabetes, diabetes + glibenclamide (0.25 mg/kg), diabetes + extract (200 or 300 mg/kg), and extract (200 or 300 mg/kg). Diabetes was induced with intraperitoneal injection of nicotinamide (NA) and streptozotocin (STZ). Twenty-four hours after the last extract and drug administration, serum samples, testes, and cauda epididymis were removed immediately for experimental assessment. Body weight, serum luteinizing hormone (LH), follicle stimulating hormone (FSH), and testosterone levels, and sperm count (P lappa plant has an effect on the health of the reproductive system in order to improve diabetic conditions.

Effect of tetrahydrocurcumin on lipid peroxidation and lipids in streptozotocin-nicotinamide-induced diabetic rats.

Science.gov (United States)

Murugan, Pidaran; Pari, Leelavinothan

2006-08-01

Hyperlipidaemia is an associated complication of diabetes mellitus. We recently reported that tetrahydrocurcumin lowered the blood glucose in diabetic rats. In the present study, we have investigated the effect of tetrahydrocurcumin, one of the active metabolites of curcumin on lipid profile and lipid peroxidation in streptozotocin-nicotinamide-induced diabetic rats. Tetrahydrocurcumin 80 mg/kg body weight was administered orally to diabetic rats for 45 days, resulted a significant reduction in blood glucose and significant increase in plasma insulin in diabetic rats, which proved its antidiabetic effect. Tetrahydrocurcumin also caused a significant reduction in lipid peroxidation (thiobarbituric acid reactive substances and hydroperoxides) and lipids (cholesterol, triglycerides, free fatty acids and phospholipids) in serum and tissues, suggesting its role in protection against lipid peroxidation and its antihyperlipidemic effect. Tetrahydrocurcumin showed a better effect when compared with curcumin. Results of the present study indicate that tetrahydrocurcumin showed antihyperlipidaemic effect in addition to its antidiabetic effect in type 2 diabetic rats.

Effect of aqueous bark extract of Garuga pinnata Roxb. in streptozotocin-nicotinamide induced type-II diabetes mellitus.

Science.gov (United States)

Shirwaikar, Annie; Rajendran, K; Barik, Rakesh

2006-09-19

A study was undertaken to evaluate the antihyperglycemic activity of aqueous extract of bark of Garuga pinnata Roxb. (Burseraceae). The various parameters studied included fasting blood sugar levels, serum lipid levels, liver glycogen content, serum insulin level and glycated hemoglobin in diabetic and normal rats. Streptozotocin-nicotinamide was used to induce type-II diabetes mellitus. Treatment with the extract at two dose levels showed a significant increase in the liver glycogen and serum insulin level and a significant decrease in fasting blood glucose and glycated hemoglobin levels. The total cholesterol and serum triglycerides levels were also significantly reduced and the HDL cholesterol levels were significantly increased upon treatment with the extract thus proving the potent antidiabetic property of the plant.

A rapid microwave induced synthesis of [carboxyl-14C]-nicotinic acid (vitamin B3) and [carbonyl-14C]-nicotinamide using K14CN

International Nuclear Information System (INIS)

Ravi, S.; Mathew, K.M.; Sivaprasad, N.

2008-01-01

Microwave assisted direct aromatic substitution of 3-bromopyridine with K 14 CN as the cyanide source and catalytic amount of tetrabutylammonium bromide afforded [3- 14 C]-cyanopyridine 3 in 90% yield. Microwave assisted hydrolysis of 3 with a mixture of concentrated hydrochloric acid and propionic acid afforded [carboxyl- 14 C]-nicotinic acid in 95% yield whereas microwave assisted hydrolysis of 3 with a mixture of concentrated sulfuric acid and propionic acid afforded [carbonyl- 14 C]-nicotinamide in 85% yield. (author)

Ultrasound assisted combined molecularly imprinted polymer for selective extraction of nicotinamide in human urine and milk samples: Spectrophotometric determination and optimization study.

Science.gov (United States)

Asfaram, Arash; Ghaedi, Mehrorang; Dashtian, Kheibar

2017-01-01

Ultrasound-assisted dispersive solid phase microextraction followed by UV-vis spectrophotometer (UA-DSPME-UV-vis) was designed for extraction and preconcentration of nicotinamide (vitamin B 3 ) by HKUST-1 metal organic framework (MOF) based molecularly imprinted polymer (MIP). This new material was characterized by FTIR and FE-SEM techniques. The preliminary Plackett-Burman design was used for screening and subsequently the central composite design justifies significant terms and possible construction of mathematical equation which give the individual and cooperative contribution of variables like HKUST-1-MOF-NA-MIP mass, sonication time, temperature, eluent volume, pH and vortex time. Accordingly the optimum condition was set as: 2.0mg HKUST-1-MOF-NA-MIP, 200μL eluent and 5.0min sonication time in center points other variables were determined as the best conditions to reach the maximum recovery of the analyte. The UA-DSPME-UV-vis method performances like excellent linearity (LR), limits of detection (LOD), limits of quantification of 10-5000μgL -1 with R 2 of 0.99, LOD (1.96ngmL -1 ), LOQ (6.53μgL -1 ), respectively show successful and accurate applicability of the present method for monitoring analytes with within- and between-day precision of 0.96-3.38%. The average absolute recoveries of the nicotinamide extracted from the urine, milk and water samples were 95.85-101.27%. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of Hydro-alcoholic Extract from Arctium lappa L. (Burdock) Root on Gonadotropins, Testosterone, and Sperm Count and Viability in Male Mice with Nicotinamide/ Streptozotocin-Induced Type 2 Diabetes

OpenAIRE

AHANGARPOUR, Akram; OROOJAN, Ali Akbar; HEIDARI, Hamid; GHAEDI, Ehsan; TAHERKHANI, Reza

2015-01-01

Background: Reproductive dysfunction is a complication of diabetes. Arctium lappa (burdock) root has hypoglycemic and antioxidative properties, which are traditionally used for treatment of impotence and sterility. Therefore, the aim of this study is to investigate the effects of its hydro alcoholic extract on gonadotropin, testosterone, and sperm parameters in nicotinamide/ streptozotocin-induced diabetic mice.

Nicotinamide N-Methyltransferase Suppression Participates in Nickel-Induced Histone H3 Lysine9 Dimethylation in BEAS-2B Cells

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Qian Li

2017-04-01

Full Text Available Background: Nickel compounds are well-established human carcinogens with weak mutagenic activity. Histone methylation has been proposed to play an important role in nickel-induced carcinogenesis. Nicotinamide N-methyltransferase (NNMT decreases histone methylation in several cancer cells by altering the cellular ratio of S-adenosylmethionine (SAM to S-adenosylhomocysteine (SAH. However, the role of NNMT in nickel-induced histone methylation remains unclear. Methods: BEAS-2B cells were exposed to different concentrations of nickel chloride (NiCl2 for 72 h or 200 μM NiCl2 for different time periods. Histone H3 on lysine 9 (H3K9 mono-, di-, and trimethylation and NNMT protein levels were measured by western blot analysis. Expressions of NNMT mRNA and the H3k9me2-associated genes, mitogen-activated protein kinase 3 (MAP2K3 and dickkopf1 (DKK1, were determined by qPCR analysis. The cellular ratio of nicotinamide adenine dinucleotide (NAD+ to reduced NAD (NADH and SAM/SAH ratio were determined. Results: Exposure of BEAS-2B cells to nickel increased H3K9 dimethylation (H3K9me2, suppressed the expressions of H3K9me2-associated genes (MAP2K3 and DKK1, and induced NNMT repression at both the protein and mRNA levels. Furthermore, over-expression of NNMT inhibited nickel-induced H3K9me2 and altered the cellular SAM/SAH ratio. Additionally, the NADH oxidant phenazine methosulfate (PMS not only reversed the nickel-induced reduction in NAD+/NADH but also inhibited the increase in H3K9me2. Conclusions: These findings indicate that the repression of NNMT may underlie nickel-induced H3K9 dimethylation by altering the cellular SAM/SAH ratio.

Progression to type 1 diabetes in islet cell antibody-positive relatives in the European Nicotinamide Diabetes Intervention Trial

DEFF Research Database (Denmark)

Bingley, P J; Gale, E A M; Reimers, Jesper Irving

2006-01-01

of development of diabetes within 5 years varied according to age, relationship to the proband, positivity for IAA, IA-2A and GADA, number and combination of islet antibodies, HLA class II genotype, baseline glucose tolerance, and first-phase insulin secretion, but not gender or incidence of childhood type 1...... of additional antibody markers, but not antibody type or genotype. Individuals diabetes within 5 years and these combined criteria identified 81% of the cases in the whole cohort. CONCLUSIONS/INTERPRETATION: We suggest that screening......AIMS/HYPOTHESIS: To examine the role of additional immune, genetic and metabolic risk markers in determining risk of diabetes in islet cell antibody (ICA)-positive individuals with a family history of type 1 diabetes recruited into the European Nicotinamide Diabetes Intervention Trial. METHODS...

Nicotinamide clearance by Pnc1 directly regulates Sir2-mediated silencing and longevity.

Science.gov (United States)

Gallo, Christopher M; Smith, Daniel L; Smith, Jeffrey S

2004-02-01

The Saccharomyces cerevisiae Sir2 protein is an NAD(+)-dependent histone deacetylase (HDAC) that functions in transcriptional silencing and longevity. The NAD(+) salvage pathway protein, Npt1, regulates Sir2-mediated processes by maintaining a sufficiently high intracellular NAD(+) concentration. However, another NAD(+) salvage pathway component, Pnc1, modulates silencing independently of the NAD(+) concentration. Nicotinamide (NAM) is a by-product of the Sir2 deacetylase reaction and is a natural Sir2 inhibitor. Pnc1 is a nicotinamidase that converts NAM to nicotinic acid. Here we show that recombinant Pnc1 stimulates Sir2 HDAC activity in vitro by preventing the accumulation of NAM produced by Sir2. In vivo, telomeric, rDNA, and HM silencing are differentially sensitive to inhibition by NAM. Furthermore, PNC1 overexpression suppresses the inhibitory effect of exogenously added NAM on silencing, life span, and Hst1-mediated transcriptional repression. Finally, we show that stress suppresses the inhibitory effect of NAM through the induction of PNC1 expression. Pnc1, therefore, positively regulates Sir2-mediated silencing and longevity by preventing the accumulation of intracellular NAM during times of stress.

Cerebral ischemia is exacerbated by extracellular nicotinamide phosphoribosyltransferase via a non-enzymatic mechanism.

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Bing Zhao

Full Text Available Intracellular nicotinamide phosphoribosyltransferase (iNAMPT in neuron has been known as a protective factor against cerebral ischemia through its enzymatic activity, but the role of central extracellular NAMPT (eNAMPT is not clear. Here we show that eNAMPT protein level was elevated in the ischemic rat brain after middle-cerebral-artery occlusion (MCAO and reperfusion, which can be traced to at least in part from blood circulation. Administration of recombinant NAMPT protein exacerbated MCAO-induced neuronal injury in rat brain, while exacerbated oxygen-glucose-deprivation (OGD induced neuronal injury only in neuron-glial mixed culture, but not in neuron culture. In the mixed culture, NAMPT protein promoted TNF-α release in a time- and concentration-dependent fashion, while TNF-α neutralizing antibody protected OGD-induced, NAMPT-enhanced neuronal injury. Importantly, H247A mutant of NAMPT with essentially no enzymatic activity exerted similar effects on ischemic neuronal injury and TNF-α release as the wild type protein. Thus, eNAMPT is an injurious and inflammatory factor in cerebral ischemia and aggravates ischemic neuronal injury by triggering TNF-α release from glia cells, via a mechanism not related to NAMPT enzymatic activity.

Template-directed ligation of tethered mononucleotides by t4 DNA ligase for kinase ribozyme selection.

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David G Nickens

used as the tethered nucleotide. CONCLUSIONS/SIGNIFICANCE: Our results reveal a novel activity for T4 DNA ligase (template-directed ligation of a tethered mononucleotide and establish this partition scheme as being suitable for the selection of ribozymes that phosphorylate mononucleoside substrates.

High specificity of spot urinary free metanephrines in diagnosis and prognosis of pheochromocytomas and paragangliomas by HPLC with electrochemical detection.

Science.gov (United States)

Zuo, Ming; Zhen, Qianna; Zhang, Xiaoqing; Zou, Wenbi; Yang, Xiangchun; Tian, Gang; Shi, Zhenghu; Li, Qifu; Ding, Min

2018-03-01

The metanephrines (MNs) in plasma and urine were proposed as biomarkers for the diagnosis of pheochromocytomas and paragangliomas (PPGLs). However, plasma free MNs and 24h urinary fractionated MNs were not satisfactory enough in specificity for the diagnosis of PPGLs. Moreover, the collection of 24h urine was inconvenient. This work examined the diagnostic and prognostic efficiency of free MNs in spot urine for PPGLs. We measured free MNs concentration in spot urine and plasma of 28 PPGLs patients and 155 control subjects by HPLC with electrochemical detection. Postoperative free MNs levels in spot urine and plasma of 14 PPGLs patients were also determined. Creatinine (Cr) concentration was used for the correction of urine volume. The specificity of spot urinary free MNs/Cr in the diagnosis of PPGLs was significantly higher than that of plasma free MNs [normetanephrine (NMN), 98.7% (95.4%-99.8%) vs 93.0% (87.4%-96.6%); metanephrine (MN), 93.6% (88.5%-96.9%) vs 84.5% (77.5%-90.0%)]. Meanwhile, the positive likelihood ratios for spot urinary free NMN/Cr and MN/Cr were 69.21 and 13.29, compared with 12.68 and 5.30 for plasma free NMN and MN, respectively. For the PPGLs patients underwent surgery, the plasma free MNs level appeared an abnormal elevation and yielded false-positive results for some patients. Our findings were validated in an independent cohort, resulting in the specificity of 100% for both urinary free NMN/Cr and MN/Cr, and 97.3% and 83.8% for plasma free NMN and MN, respectively. Spot urinary free MNs/Cr, superior to plasma free MNs, presented a promising biomarker for the diagnosis and prognosis of PPGLs. Copyright © 2017 Elsevier B.V. All rights reserved.

Kynureninase-type enzymes and the evolution of the aerobic tryptophan-to-nicotinamide adenine dinucleotide pathway

Energy Technology Data Exchange (ETDEWEB)

Gaertner, F.H.; Shetty, A.S.

1977-01-01

Kynureninase-type (L-kynurenine hydrolase, EC 3.7.1.3) activity has been found to be present in the livers of fish, amphibia, reptiles, and birds. In addition to past information concerning this enzyme activity in mammalian liver, it is now clear that all the major classes of vertebrates carry a highly specialized kynureninase-type enzyme, which we have termed a hydroxykynureninase. To compare the reactivities of these enzymes with L-kynurenine and L-3-hydroxykynurenine, ratios of tau values (K/sub m//V) were used. Based on this comparison, the bacterium Pseudomonas fluorescens carries the most efficient kynureninase, whereas the amphibian Xenopus laevis has the most efficient hydroxykynurenase. In these two cases, the ratio of tau values differs by a factor of 38,000. It is hypothesized that the tryptophan-to-nicotinamide adenine dinucleotide biosynthetic pathway evolved from a catabolic system of enzymes, and that the differences observed in the kynureninase-type enzymes between lower and higher organisms reflect the specialization of the function of these enzymes from a strictly catabolic role to an anabolic one during the course of evolution.

Preclinical evidence of mitochondrial nicotinamide adenine dinucleotide as an effective alarm parameter under hypoxia

Science.gov (United States)

Shi, Hua; Sun, Nannan; Mayevsky, Avraham; Zhang, Zhihong; Luo, Qingming

2014-01-01

Early detection of tissue hypoxia in the intensive care unit is essential for effective treatment. Reduced nicotinamide adenine dinucleotide (NADH) has been suggested to be the most sensitive indicator of tissue oxygenation at the mitochondrial level. However, no experimental evidence comparing the kinetics of changes in NADH and other physiological parameters has been provided. The aim of this study is to obtain the missing data in a systematic and reliable manner. We constructed four acute hypoxia models, including hypoxic hypoxia, hypemic hypoxia, circulatory hypoxia, and histogenous hypoxia, and measured NADH fluorescence, tissue reflectance, cerebral blood flow, respiration, and electrocardiography simultaneously from the induction of hypoxia until death. We found that NADH was not always the first onset parameter responding to hypoxia. The order of responses was mainly affected by the cause of hypoxia. However, NADH reached its alarm level earlier than the other monitored parameters, ranging from several seconds to >10 min. As such, we suggest that the NADH can be used as a hypoxia indicator, although the exact level that should be used must be further investigated. When the NADH alarm is detected, the body still has a chance to recover if appropriate and timely treatment is provided.

Changes in phosphorylation of adenosine phosphate and redox state of nicotinamide-adenine dinucleotide (phosphate) in Geobacter sulfurreducens in response to electron acceptor and anode potential variation

KAUST Repository

Rose, Nicholas D.; Regan, John M.

2015-01-01

© 2015 Elsevier B.V. Geobacter sulfurreducens is one of the dominant bacterial species found in biofilms growing on anodes in bioelectrochemical systems. The intracellular concentrations of reduced and oxidized forms of nicotinamide-adenine dinucleotide (NADH and NAD⁺, respectively) and nicotinamide-adenine dinucleotide phosphate (NADPH and NADP⁺, respectively) as well as adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP) were measured in G. sulfurreducens using fumarate, Fe(III)-citrate, or anodes poised at different potentials (110, 10, -90, and -190mV (vs. SHE)) as the electron acceptor. The ratios of CNADH/CNAD+ (0.088±0.022) and CNADPH/CNADP+ (0.268±0.098) were similar under all anode potentials tested and with Fe(III)-citrate (reduced extracellularly). Both ratios significantly increased with fumarate as the electron acceptor (0.331±0.094 for NAD and 1.96±0.37 for NADP). The adenylate energy charge (the fraction of phosphorylation in intracellular adenosine phosphates) was maintained near 0.47 under almost all conditions. Anode-growing biofilms demonstrated a significantly higher molar ratio of ATP/ADP relative to suspended cultures grown on fumarate or Fe(III)-citrate. These results provide evidence that the cellular location of reduction and not the redox potential of the electron acceptor controls the intracellular redox potential in G. sulfurreducens and that biofilm growth alters adenylate phosphorylation.

Changes in phosphorylation of adenosine phosphate and redox state of nicotinamide-adenine dinucleotide (phosphate) in Geobacter sulfurreducens in response to electron acceptor and anode potential variation

KAUST Repository

Rose, Nicholas D.

2015-12-01

© 2015 Elsevier B.V. Geobacter sulfurreducens is one of the dominant bacterial species found in biofilms growing on anodes in bioelectrochemical systems. The intracellular concentrations of reduced and oxidized forms of nicotinamide-adenine dinucleotide (NADH and NAD⁺, respectively) and nicotinamide-adenine dinucleotide phosphate (NADPH and NADP⁺, respectively) as well as adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP) were measured in G. sulfurreducens using fumarate, Fe(III)-citrate, or anodes poised at different potentials (110, 10, -90, and -190mV (vs. SHE)) as the electron acceptor. The ratios of CNADH/CNAD+ (0.088±0.022) and CNADPH/CNADP+ (0.268±0.098) were similar under all anode potentials tested and with Fe(III)-citrate (reduced extracellularly). Both ratios significantly increased with fumarate as the electron acceptor (0.331±0.094 for NAD and 1.96±0.37 for NADP). The adenylate energy charge (the fraction of phosphorylation in intracellular adenosine phosphates) was maintained near 0.47 under almost all conditions. Anode-growing biofilms demonstrated a significantly higher molar ratio of ATP/ADP relative to suspended cultures grown on fumarate or Fe(III)-citrate. These results provide evidence that the cellular location of reduction and not the redox potential of the electron acceptor controls the intracellular redox potential in G. sulfurreducens and that biofilm growth alters adenylate phosphorylation.

Selective and membrane-permeable small molecule inhibitors of nicotinamide N-methyltransferase reverse high fat diet-induced obesity in mice.

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Neelakantan, Harshini; Vance, Virginia; Wetzel, Michael D; Wang, Hua-Yu Leo; McHardy, Stanton F; Finnerty, Celeste C; Hommel, Jonathan D; Watowich, Stanley J

2018-01-01

There is a critical need for new mechanism-of-action drugs that reduce the burden of obesity and associated chronic metabolic comorbidities. A potentially novel target to treat obesity and type 2 diabetes is nicotinamide-N-methyltransferase (NNMT), a cytosolic enzyme with newly identified roles in cellular metabolism and energy homeostasis. To validate NNMT as an anti-obesity drug target, we investigated the permeability, selectivity, mechanistic, and physiological properties of a series of small molecule NNMT inhibitors. Membrane permeability of NNMT inhibitors was characterized using parallel artificial membrane permeability and Caco-2 cell assays. Selectivity was tested against structurally-related methyltransferases and nicotinamide adenine dinucleotide (NAD + ) salvage pathway enzymes. Effects of NNMT inhibitors on lipogenesis and intracellular levels of metabolites, including NNMT reaction product 1-methylnicotianamide (1-MNA) were evaluated in cultured adipocytes. Effects of a potent NNMT inhibitor on obesity measures and plasma lipid were assessed in diet-induced obese mice fed a high-fat diet. Methylquinolinium scaffolds with primary amine substitutions displayed high permeability from passive and active transport across membranes. Importantly, methylquinolinium analogues displayed high selectivity, not inhibiting related SAM-dependent methyltransferases or enzymes in the NAD + salvage pathway. NNMT inhibitors reduced intracellular 1-MNA, increased intracellular NAD + and S-(5'-adenosyl)-l-methionine (SAM), and suppressed lipogenesis in adipocytes. Treatment of diet-induced obese mice systemically with a potent NNMT inhibitor significantly reduced body weight and white adipose mass, decreased adipocyte size, and lowered plasma total cholesterol levels. Notably, administration of NNMT inhibitors did not impact total food intake nor produce any observable adverse effects. These results support development of small molecule NNMT inhibitors as therapeutics to

Sympatho-adrenergic activation by endurance exercise: Effect on metanephrines spillover and its role in predicting athlete's performance.

Science.gov (United States)

Danese, Elisa; Tarperi, Cantor; Salvagno, Gian Luca; Guzzo, Alessandra; Sanchis-Gomar, Fabian; Festa, Luca; Bertinato, Luciano; Montagnana, Martina; Schena, Federico; Lippi, Giuseppe

2018-03-20

The sympatho-adrenergic activation during exercise is implicated in many cardiovascular respiratory and metabolic adaptations which have been thought to partially explain the different levels of performance observed between trained and untrained subjects. To date, no evidence exists about the association between competition performance and markers of "acute stress response". We designed this study to investigate; (i) the acute sympatho-adrenergic activation during endurance exercise in recreational runners by measuring plasma levels of free metanephrine (MN) and normethanephrine (NMN) before and after a half-marathon run; (ii) the association between the metanephrines levels and the running time. 26 amateur runners (15 males, 11 females) aged 30 to 63 years were enrolled. The quantification of MN and NMN was performed by LC-MS/MS. Anthropometric ergonomic and routine laboratory data were recorded. Statistical analyses included paired T -test, univariate and multivariate regressions. The post-run values of MN and NMN displayed a nearly 3.5 and 7 fold increase respectively compared to the baseline values ( p performance. No correlations were found for MN values. NMN is a reliable marker of sympatho-adrenergic activation by exercise and can predict endurance performance in the individual athlete. Adaptation phenomenon occurring not only in the adrenal medulla might represent the biological mechanism underlying this association. Further studies on sympatho-adrenergic activation, competition performance and training status should contemplate the measurement of these metabolites instead of their unstable precursors.

Expression patterns of nicotinamide phosphoribosyltransferase and nicotinic acid phosphoribosyltransferase in human malignant lymphomas.

Science.gov (United States)

Olesen, Uffe Høgh; Hastrup, Nina; Sehested, Maxwell

2011-04-01

The purpose of the study was to determine in human malignant lymphomas the expression patterns of nicotinamide phosphoribosyltransferase (NAMPT) and nicotinic acid phosphoribosyltransferase (NAPRT), the primary, rate-limiting enzymes in the synthesis of NAD+. NAMPT is a potential biomarker for sensitivity to NAMPT inhibitors and NAPRT is a biomarker for the use of nicotinic acid as a chemoprotectant in treatment with NAMPT inhibitors. The NAMPT inhibitor, APO866, is currently in clinical phase II trials in lymphomas. The expression of NAMPT and NAPRT was investigated in 53 samples of malignant lymphomas (diffuse large B-cell lymphoma, follicular B-cell lymphoma, Hodgkin's lymphoma and peripheral T-cell lymphoma). The expression of NAMPT was generally high in the more aggressive malignant lymphomas, with >80% strong expression, whereas the expression in the more indolent follicular lymphoma (FL) was significantly lower (>75% moderate or low expression, p = 0.0002). NAMPT was very highly expressed in Hodgkin Reed-Sternberg cells in Hodgkin's lymphoma. NAPRT expression was more varied (p > 0.0001) with 30-50% low expression except for Hodgkin's lymphoma where 85% displayed low expression (p = 0.0024). In conclusion, FL are a promising target for NAMPT inhibitors whereas substantial subsets of malignant lymphomas especially in Hodgkin lymphoma may be suitable for a combination treatment with nicotinic acid and NAMPT inhibitors. © 2011 The Authors. APMIS © 2011 APMIS.

Crystal structure of trans-diaquabis(4-cyanobenzoato-κObis(nicotinamide-κN1cobalt(II

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Gülçin Şefiye Aşkın

2015-05-01

Full Text Available In the title complex, [Co(C8H4NO22(C6H6N2O2(H2O2], the CoII atom is located on an inversion centre and is coordinated by two 4-cyanobenzoate (CNB anions, two nicotinamide (NA ligands and two water molecules. The four O atoms in the equatorial plane form a slightly distorted square-planar arrangement, while the slightly distorted octahedral coordination sphere is completed by the two N atoms of the NA ligands in the axial positions. The dihedral angle between the carboxylate group and the adjacent benzene ring is 22.11 (15°, while the pyridine and benzene rings are oriented at a dihedral angle of 89.98 (5°. In the crystal, intermolecular N—H...O and O—H...O hydrogen bonds link the molecules, enclosing R22(8 and R44(8 ring motifs, forming layers parallel to (100. The layers are linked via C—H...O and C—H...N hydrogen bonds, resulting in a three-dimensional network. A weak C—H...π interaction is also observed.

Enhancement of in vivo Radiosensitization by Combination with Pentoxifylline and Nicotinamide

International Nuclear Information System (INIS)

Lee, In Tae; Cho, Moon June

1991-01-01

Pentoxifylline (PENTO) has been known to improve RBC fluidity, and thus improve the flux of RBC through narrow capillaries. Additionally, PENTO also decreases the O2 release from RBC. Nicotinamide (N4) has been reported to decrease the number of acutely hypoxic cells in tumors by temporarily increasing tumor blood flow. Therefore, the purpose of this study was to examine whether the combination of PENTO and NA (PENTO+NA) would reduce the radioresistance of the the FSa II murine fibrosarcoma by oxygenation the hypoxic cells. We observed a significantly enhanced radiation-induced growth delay of the FSa II tumors by PENTO-NA. Thus the enhancement ration was between 2.5 and 2.8 in growth delay assay. The TCD 50 of control tumors was about 57 Gy, but that of PENTO-NA treated tumors was about 32 Gy. The TCD50 was modified by a factor of 1.8. We also observed that PENTO+NA, changes in tumor blood flow and intratumor pO2 were measured using laser Doppler flowmetry and O2 microelectrode methods. The tumor blood flow significantly increased at 10 min. after injection of PENTO+NA. Furthermore, we also found that PENTO+NA significantly increased intratumor pO2 from 8 to 19 mmHg. We concluded that PENTO+NA was far more effective than NA alone or PENTO alone. The increase in the response of tumor in vivo to X-irradiation appeared to be due mainly to an increase in the tumor oxygenation. Further studies using various concentrations of PENTO alone and in combination with NA to obtain better sequencing and maximal radiosensitization are warranted

An azoreductase, aerobic NADH-dependent flavoprotein discovered from Bacillus sp.: functional expression and enzymatic characterization.

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Ooi, Toshihiko; Shibata, Takeshi; Sato, Reiko; Ohno, Hiroaki; Kinoshita, Shinichi; Thuoc, Tran Linh; Taguchi, Seiichi

2007-05-01

The gene coding for an azoreductase, designated as an azrA, was cloned by polymerase chain reaction amplification from the genomic DNA of Bacillus sp. strain B29 isolated from soil. The azrA encoded a protein of 208 amino acids with calculated molecular mass of 22,766 Da. The enzyme was heterologously expressed in Escherichia coli with a strong band of 23 kDa on sodium dodecyl sulfate polyacrylamide gel electrophoresis. Purified recombinant AzrA was a homodimer with a native molecular mass of 48 kDa containing two molecules of flavin mononucleotide (FMN; oxidized). This activity was oxygen insensitive and was nicotinamide adenine dinucleotide (reduced form; NADH) dependent. Recombinant AzrA exhibited a broad pH stability between 6 and 10 with a temperature optimum of 60-80 degrees C. The enzyme cleaved the model azo compound of methyl red [MR, 4'-(dimethylamino)-azobenzene-2-carboxylic acid] into 2-aminobenzoic acid and N, N'-dimethyl-p-phenylenediamine by ping-pong mechanism. The enzyme was not only able to decolorize MR but also able to decolorize sulfonated azo dyes such as Orange I and Acid Red 88.

NMNAT2:HSP90 Complex Mediates Proteostasis in Proteinopathies.

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Yousuf O Ali

2016-06-01

Full Text Available Nicotinamide mononucleotide adenylyl transferase 2 (NMNAT2 is neuroprotective in numerous preclinical models of neurodegeneration. Here, we show that brain nmnat2 mRNA levels correlate positively with global cognitive function and negatively with AD pathology. In AD brains, NMNAT2 mRNA and protein levels are reduced. NMNAT2 shifts its solubility and colocalizes with aggregated Tau in AD brains, similar to chaperones, which aid in the clearance or refolding of misfolded proteins. Investigating the mechanism of this observation, we discover a novel chaperone function of NMNAT2, independent from its enzymatic activity. NMNAT2 complexes with heat shock protein 90 (HSP90 to refold aggregated protein substrates. NMNAT2's refoldase activity requires a unique C-terminal ATP site, activated in the presence of HSP90. Furthermore, deleting NMNAT2 function increases the vulnerability of cortical neurons to proteotoxic stress and excitotoxicity. Interestingly, NMNAT2 acts as a chaperone to reduce proteotoxic stress, while its enzymatic activity protects neurons from excitotoxicity. Taken together, our data indicate that NMNAT2 exerts its chaperone or enzymatic function in a context-dependent manner to maintain neuronal health.

Phenylacetic acid co-crystals with acridine, caffeine, isonicotinamide and nicotinamide: Crystal structures, thermal analysis, FTIR spectroscopy and Hirshfeld surface analysis

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Amombo Noa, Francoise M.; Jacobs, Ayesha

2017-07-01

Co-crystals of phenylacetic acid (PAA) with acridine (ACR), caffeine (CAF), isonicotinamide (INM) and nicotinamide (NAM) have been successfully prepared and characterised by single crystal X-ray diffraction, FTIR spectroscopy, thermal analysis and Hirshfeld surface analysis. The ACR, INM and NAM co-crystals with PAA exhibit the carboxylic acid-pyridine heterosynthon. Furthermore the amide-amide supramolecular homosynthon is observed in the PAA co-crystals with INM and NAM as well as Nsbnd H⋯O interactions between the acid and the respective base. The CAF co-crystal exhibits hydrogen bonding between the imidazole nitrogen and the COOH group of the PAA. The compounds demonstrate different stoichiometries; for PAA·ACR and PAA·INM a 1:1 ratio is displayed, a 2:1 in 2PAA·CAF and a 2:2 in the case of 2PAA·2NAM.

Fluorimetric study of the interaction between nicotinamide adenine dinucleotide phosphate and tetracycline-europium complex and its application

International Nuclear Information System (INIS)

Peng Qian; Hou Faju; Ge Xiaoxia; Jiang Chongqiu; Gong Shubo

2005-01-01

A new spectrofluorimetric method was developed for the determination of trace amount of nicotinamide adenine dinucleotide phosphate (NADP). Using europium (Eu 3+ )-tetracycline (TC) complex as a fluorescent probe, in the buffer solution of pH 7.60. NADP can remarkably enhance the fluorescence intensity of the Eu 3+ -TC complex at λ = 612 nm and the enhanced fluorescence intensity of Eu 3+ ion is in proportion to the concentration of NADP. Optimum conditions for the determination of NADP were also investigated. The dynamic range for the determination of NADP is 4.4 x 10 -7 to 2.2 x 10 -6 mol l -1 with detection limit of 6.9 x 10 -8 mol l -1 . This method is simple, practical and relatively free interference from coexisting substances and can be successfully applied to determination of NADP in synthetic water samples and in serum samples. Moreover, the enhancement mechanisms of the fluorescence intensity in the Eu 3+ -TC system and the Eu 3+ -TC-NADP system have been also discussed

Antidiabetic Potential of Kefir Combination from Goat Milk and Soy Milk in Rats Induced with Streptozotocin-Nicotinamide.

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Nurliyani; Harmayani, Eni; Sunarti

2015-01-01

The study aimed to evaluate the effect of kefir combination from goat milk and soy milk on lipid profile, plasma glucose, glutathione peroxidase (GPx) activity and the improvement of pancreatic β-cell in diabetic rats. Male rats were divided into five treatments: normal control, diabetic control, goat milk kefir, combination of goat milk-soy milk kefir and soy milk kefir. All rats were induced by streptooztocin-nicotinamide (STZ-NA), except for normal control. After 35 d experiment, the rats were sampled for blood, sacrificed and sampled for pancreatic tissues. Results showed that diabetic rats fed kefir combination had higher (pkefir. Decreasing of plasma glucose in diabetic rats fed kefir combination was higher (pkefir. The activity of GPx in diabetic rats fed three kinds of kefir were higher (pkefir combination was the same as the normal control, but it was higher than diabetic control. It was concluded that kefir combination can be used as antidiabetic through maintaining in serum triglyceride, decreasing in plasma glucose, increasing in GPx activity and improving in pancreatic β-cells.

Children at risk of diabetes type 1. Treatment with acetyl-L-carnitine plus nicotinamide - case reports.

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Fernandez, Ivana Cristina; Del Carmen Camberos, María; Passicot, Gisel Anabel; Martucci, Lucía Camila; Cresto, Juan Carlos

2013-01-01

Abstract Objectives: The aim was to evaluate the treatment with acetyl-L-carnitine (50 mg/kg/day) and nicotinamide (25 mg/kg/day) in children at risk of type 1 diabetes. This treatment was effective and harmless in experimental type 1 diabetes in mice. Nine out of seventy healthy participants of the type 1 diabetes risk study were treated. They were typified for diabetes with HLA-DQB1 and positive autoantibodies. Children with a first peak of insulin response ≤48 µU were randomly distributed in control and treated patients. Children evolution was followed with an intravenous glucose tolerance test. Control children were treated when was another risk parameter was added. During their evolution all children were treated. Treatment periods differ (range: 120-16 months) because children began treatment at different times. During the treatment 4 patients recovered their parameters and the medication was suspended; 2 patients continued the treatment with favorable evolution. Two children evolved slowly with normal growth and development. One girl became diabetic because she was treated late. In children at risk, this treatment delays the development or remits the evolution of type 1 diabetes.

Nicotinamide-NAD sequence: redox process and related behavior, behavior and properties of intermediate and final products

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Elving, P.J.; Schmakel, C.O.; Santhanam, K.S.V.

1976-01-01

Illustrations of the application of analytical chemical techniques to the study of chemical phenomena are given. In particular, electrochemical techniques and methodology and, to a lesser extent, spectrophotometry were used to investigate the solution behavior, adsorption, redox processes including coupled chemical reactions, and allied aspects of biologically significant compounds and of their intermediate and final redox products, e.g., the behavior of the free radicals produced by initial one-electron processes. This approach is illustrated by the consideration of the behavior in aqueous and nonaqueous media of a sequence of compounds ranging from nicotinamide (3-carbamoylpyridine) to NAD + and NADP + ; the latter compounds function as coenzymes for the pyridinoproteins which are principal components in the Krebs citric acid cycle and in the electron transport chain in biological redox reactions. The discussion is presented under the following section headings: interpretation of electrochemical behavior; mechanistic patterns; kinetic aspects of charge-transfer and chemical reactions; correlation with theoretically calculated parameters; and, mechanisms of biological oxidation-reduction reactions. The use of pulse radiolysis, chronopotentiometric, and cyclic voltammetric methods in studies on free radical dimerization rates is reviewed in the discussion of the kinetic aspects of charge-transfer and chemical reactions. (188 references)

Effects of hydroalcoholic extract of Rhus coriaria seed on glucose and insulin related biomarkers, lipid profile, and hepatic enzymes in nicotinamide-streptozotocin-induced type II diabetic male mice.

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Ahangarpour, Akram; Heidari, Hamid; Junghani, Majid Salehizade; Absari, Reza; Khoogar, Mehdi; Ghaedi, Ehsan

2017-10-01

Type 2 diabetes often leads to dislipidemia and abnormal activity of hepatic enzymes. The purpose of this study was to evaluate the antidiabetic and hypolipidemic properties of Rhus coriaria ( R. coriaria ) seed extrac on nicotinamide-streptozotocin induced type 2 diabetic mice. In this experimental study, 56 male Naval Medical Research Institute mice (30-35 g) were randomly separated into seven groups: control, diabetic group, diabetic mice treated with glibenclamide (0.25 mg/kg, as standard antidiabetic drug) or R. coriaria seed extract in doses of 200 and 300 mg/kg, and control groups received these two doses of extract orally for 28 days. Induction of diabetes was done by intraperitoneal injection of nicotinamide and streptozotocin. Ultimately, body weight of mice, blood levels of glucose, insulin, hepatic enzymes, leptin, and lipid profile were assayed. After induction of type 2 diabetes, level of glucose, cholesterol, low density lipoprotein, serum glutamic oxaloacetic transaminase, and serum glutamic pyruvic transaminase increased and level of insulin and high density lipoprotein decreased remarkably. Administration of both doses of extract decreased level of glucose and cholesterol significantly in diabetic mice. LDL level decreased in treated group with dose of 300 mg/kg of the extract. Although usage of the extract improved level of other lipid profiles, insulin and hepatic enzymes, changes weren't significant. This study showed R. coriaria seeds administration has a favorable effect in controlling some blood parameters in type 2 diabetes. Therefore it may be beneficial in the treatment of diabetes.

Dynamic changes in nicotinamide pyridine dinucleotide content in normal human epidermal keratinocytes and their effect on retinoic acid biosynthesis

International Nuclear Information System (INIS)

Pinkas-Sarafova, Adriana; Markova, N.G.; Simon, M.

2005-01-01

The function of many enzymes that regulate metabolism and transcription depends critically on the nicotinamide pyridine dinucleotides. To understand the role of NAD(P)(H) in physiology and pathophysiology, it is imperative to estimate both their amount and ratios in a given cell type. In human epidermis and in cultured epidermal keratinocytes, we found that the total dinucleotide content is in the low millimolar range. The dinucleotide pattern changes during proliferation and maturation of keratinocytes in culture. Differences in the concentrations of NAD(P)(H) of 1.5- to 12-fold were observed. This resulted in alteration of the NAD(P)H/NAD(P) ratio, which could impact the differential regulation of both transcriptional and metabolic processes. In support of this notion, we provide evidence that the two-step oxidation of retinol to retinoic acid, a nuclear hormone critical for epidermal homeostasis, can be regulated by the relative physiological amounts of the pyridine dinucleotides

Pade approximants for entire functions with regularly decreasing Taylor coefficients

International Nuclear Information System (INIS)

Rusak, V N; Starovoitov, A P

2002-01-01

For a class of entire functions the asymptotic behaviour of the Hadamard determinants D n,m as 0≤m≤m(n)→∞ and n→∞ is described. This enables one to study the behaviour of parabolic sequences from Pade and Chebyshev tables for many individual entire functions. The central result of the paper is as follows: for some sequences {(n,m(n))} in certain classes of entire functions (with regular Taylor coefficients) the Pade approximants {π n,m(n) }, which provide the locally best possible rational approximations, converge to the given function uniformly on the compact set D={z:|z|≤1} with asymptotically best rate

(Solid + liquid) phase diagram for (indomethacin + nicotinamide)-methanol or methanol/ethyl acetate mixture and solubility behavior of 1:1 (indomethacin + nicotinamide) co-crystal at T = (298.15 and 313.15) K

International Nuclear Information System (INIS)

Sun, Xiaowei; Yin, Qiuxiang; Ding, Suping; Shen, Zhiming; Bao, Ying; Gong, Junbo; Hou, Baohong; Hao, Hongxun; Wang, Yongli; Wang, Jingkang; Xie, Chuang

2015-01-01

Highlights: • Ternary phase diagrams of (IMC + NCT)-methanol or methanol/ethyl acetate mixture at T = (298.15 and 313.15) K were measured. • The effects of temperature and introduced ethyl acetate on solid phase stability were discussed. • Solubility of (IMC + NCT) cocrystals was first correlated using a model considering solubility product and complexation. • Solubility of (IMC + NCT) cocrystals as a function of co-former concentration was evaluated. - Abstract: (Solid + liquid) equilibrium data for indomethacin (IMC) and nicotinamide (NCT) in both methanol (MeOH) and methanol/ethyl acetate (EA) mixture were determined using a static method at T = (298.15 and 313.15) K under atmospheric pressure. The 1:1 (IMC + NCT) co-crystal and IMC·MeOH were found in both systems under conditions investigated. The solubility of the 1:1 (IMC + NCT) co-crystal was correlated using a mathematical model consisting of both solubility product and a complexation process. Solubility of (IMC + NCT) co-crystals as a function of co-former (NCT) concentration was evaluated. It was found that temperature has a significant effect on the formation of methanol solvate in the systems investigated. Solvate formation could be suppressed either by increasing temperature or using solvent mixtures. Additionally, the solvent mixture could level out the solubility differences between IMC and NCT, resulting in larger and more symmetric regions for the (IMC + NCT) co-crystal, which would be helpful to the development of the co-crystallization process for the 1:1 (IMC + NCT) co-crystal

Reversal of endothelial dysfunction in aorta of streptozotocin-nicotinamide-induced type-2 diabetic rats by S-Allylcysteine.

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Brahmanaidu, Parim; Uddandrao, V V Sathibabu; Sasikumar, Vadivukkarasi; Naik, Ramavat Ravindar; Pothani, Suresh; Begum, Mustapha Sabana; Rajeshkumar, M Prasanna; Varatharaju, Chandrasekar; Meriga, Balaji; Rameshreddy, P; Kalaivani, A; Saravanan, Ganapathy

2017-08-01

Dietary measures and plant-based therapies as prescribed by native systems of medicine have gained attraction among diabetics with claims of efficacy. The present study investigated the effects of S-Allylcysteine (SAC) on body weight gain, glucose, insulin, insulin resistance, and nitric oxide synthase in plasma and argininosuccinate synthase (AS) and argininosuccinate lyase (ASL), lipid peroxides and antioxidant enzymes in aorta of control and streptozotocin-nicotinamide (STZ-NA)-induced diabetic rats. Changes in body weight, glucose, insulin, insulin resistance, and antioxidant profiles of aorta and mRNA expressions of nitric oxide synthase, AS, and ASL were observed in experimental rats. SAC (150 mg/kg b.w) showed its therapeutic effects similar to gliclazide in decreasing glucose, insulin resistance, lipid peroxidation, and increasing body weight; insulin, antioxidant enzymes, and mRNA levels of nitric oxide synthase, argininosuccinate synthase, and argininosuccinate lyase genes in STZ-NA rats. Histopathologic studies also revealed the protective nature of SAC on aorta. In conclusion, garlic and its constituents mediate the anti-diabetic potential through mitigating hyperglycemic status, changing insulin resistance by alleviating endothelial dysregulation in both plasma and tissues.

Magnitude of malate-aspartate reduced nicotinamide adenine dinucleotide shuttle activity in intact respiring tumor cells.

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Greenhouse, W V; Lehninger, A L

1977-11-01

Measurements of respiration, CO2 and lactate production, and changes in the levels of various key metabolites of the glycolytic sequence and tricarboxylic acid cycle were made on five lines of rodent ascites tumor cells (two strains of Ehrlich ascites tumor cells, Krebs II carcinoma, AS-30D carcinoma, and L1210 cells) incubated aerobically in the presence of uniformly labeled D-[14C]glucose. From these data, as well as earlier evidence demonstrating that the reduced nicotinamide adenine dinucleotide (NADH) shuttle in these cells requires a transaminase step and is thus identified as the malate-aspartate shuttle (W.V.V. Greenhouse and A.L. Lehninger, Cancer Res., 36: 1392-1396, 1976), metabolic flux diagrams were constructed for the five cell lines. These diagrams show the relative rates of glycolysis, the tricarboxylic acid cycle, electron transport, and the malate-aspartate shuttle in these tumors. Large amounts of cytosolic NADH were oxidized by the mitochondrial respiratory chain via the NADH shuttle, comprising anywhere from about 20 to 80% of the total flow of reducing equivalents to oxygen in these tumors. Calculations of the sources of energy for adenosine triphosphate synthesis indicated that on the average about one-third of the respiratory adenosine triphosphate is generated by electron flow originating from cytosolic NADH via the malate-aspartate shuttle.

Studies of yeast cell oxygenation and energetics by laser fluorometry of reduced nicotinamide adenine dinucleotide

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Pan, Fu-shih; Chen, Stephen; Mintzer, Robert A.; Chen, Chin-Tu; Schumacker, Paul

1991-03-01

It is of fundamental importance for biological scientists to assess cellular energetics. Under aerobic conditions, the tricarboxylic acid cycle (TCA cycle) is coupled with the mitochondrial electron cascade pathway to provide the cell with energy. The nicotinamide adenine dinucleotide-conjugated pair (NAD and NADH) is the coenzyme in numerous important biomedical reactions which include several important dehydrogenase reactions in the TCA cycle. Based on Le Chatelier's principle, NADH will accumulate when this energy production mechanism is impaired. The relative amounts of NAD and NADH in a cell are defined as the redox state of the cell (Williamson et.al. 1967) which provides a valuable index of cellular energetics. The sum of the amounts of NAD and NADH in a cell may be assumed to be constant during a finite time; therefore, a reliable means of measuring the NADH concentration would provide us with a useful indicator of tissue viability. Traditionally, the quantities of NADH and NAD may be measured by chemical assay methods. We can avoid these tediois analyses by exploiting the significant difference between the ultraviolet absorption spectra of this redox pair. However, because of the opacity of biological samples and the interference of other biochemicals that also absorb ultraviolet radiation, measurement of NADH and NAD+ concentrations in vivo by absorption spectroscopy is not feasible.

Association between Nicotinamide N-Methyltransferase Gene Polymorphisms and Obesity in Chinese Han Male College Students

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Qiong Zhou

2017-01-01

Full Text Available Some reports have shown that nicotinamide N-methyltransferase (NNMT is associated with the body mass index (BMI and energy metabolism. Here we explored the association between NNMT gene polymorphisms and obesity. The subjects were recruited from male Chinese Han college student. 289 of them (19 ≤ body fat percentage (BF% were selected as the high body fat group (HBFG, 494 of them (3 ≤ BF% < 13.5 were selected as the low body fat group (LBFG, and then a case-control study (fat versus thin was carried out to explore the association between the NNMT gene polymorphism and the body composition using tagSNPs method. A tagSNP (rs10891644 in NNMT gene was found significantly associated with the body composition (P<0.0026. At this locus, the BF% for the genotype GT, TT, and GG were 14.56±8.35, 13.47±8.11, and 12.42±7.50, respectively, and the differences between the GT and the GG + TT were highly significant (P<0.01; the ORadjusted value of the GT versus (GG + TT was 1.716 (Padjusted=0.002, 95% CI = 1.240–2.235. Therefore, the variation of the tagSNP, rs10891644, is significantly associated with obesity and the GT carriers are the susceptible population.

Coformer selection based on degradation pathway of drugs: a case study of adefovir dipivoxil-saccharin and adefovir dipivoxil-nicotinamide cocrystals.

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Gao, Yuan; Gao, Jing; Liu, Ziling; Kan, Hongliang; Zu, Hui; Sun, Wanjin; Zhang, Jianjun; Qian, Shuai

2012-11-15

Adefovir dipivoxil (AD) is a bis(pivaloyloxymethyl) prodrug of adefovir with chemical stability problem. It undergoes two degradation pathways including hydrolysis and dimerization during storage. Pharmaceutical cocrystallization exhibits a promising approach to enhance aqueous solubility as well as physicochemical stability. In this study we attempted to prepare and investigate the physiochemical properties of AD cocrystals, which were formed with two coformers having different acidity and alkalinity (weakly acidic saccharin (SAC) and weakly basic nicotinamide (NCT)). The presence of different coformer molecules along with AD resulted in altered physicochemical properties. AD-SAC cocrystal showed great improvement in solubility and chemical stability, while AD-NCT did not. Several potential factors giving rise to different solid-state properties were summarized. Different coformers resulted in different cocrystal formation, packing style and hydrogen bond formation. This study could provide the coformer selection strategy based on degradation pathways for some unstable drugs in pharmaceutical cocrystal design. Copyright © 2012 Elsevier B.V. All rights reserved.

The human amygdaloid complex: a cytologic and histochemical atlas using Nissl, myelin, acetylcholinesterase and nicotinamide adenine dinucleotide phosphate diaphorase staining.

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Sims, K S; Williams, R S

1990-01-01

We examined the distribution of acetylcholinesterase and nicotinamide adenine dinucleotide phosphate diaphorase enzyme activity in the human amygdala using histochemical techniques. Both methods revealed compartments of higher or lower enzyme activity, in cells or neuropil, which corresponded to the nuclear subdivisions of the amygdala as defined with classical Nissl and myelin methods. The boundaries between the histochemical compartments were usually so sharp that the identification of these nuclear subdivisions was enhanced. There was also variation of staining intensity within many of the nuclear subdivisions, such as the lateral and central nuclei, anterior amygdaloid area and the intercalated groups. This histochemical difference corresponded to more subtle differences in Nissl and myelin staining patterns, and suggests further structural subdivisions of potential functional significance. We present a revised scheme of anatomical parcellation of the human amygdala based upon serial analysis with all four techniques. Our expectation is that this will allow the delineation of a clearer homology between the cytoarchitectonic subdivisions of the human amygdala and those of experimental animals.

NAMPT-Mediated Salvage Synthesis of NAD+ Controls Morphofunctional Changes of Macrophages

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Venter, Gerda; Oerlemans, Frank T. J. J.; Willemse, Marieke; Wijers, Mietske; Fransen, Jack A. M.; Wieringa, Bé

2014-01-01

Functional morphodynamic behavior of differentiated macrophages is strongly controlled by actin cytoskeleton rearrangements, a process in which also metabolic cofactors ATP and NAD(H) (i.e. NAD+ and NADH) and NADP(H) (i.e. NADP+ and NADPH) play an essential role. Whereas the link to intracellular ATP availability has been studied extensively, much less is known about the relationship between actin cytoskeleton dynamics and intracellular redox state and NAD+-supply. Here, we focus on the role of nicotinamide phosphoribosyltransferase (NAMPT), found in extracellular form as a cytokine and growth factor, and in intracellular form as one of the key enzymes for the production of NAD+ in macrophages. Inhibition of NAD+ salvage synthesis by the NAMPT-specific drug FK866 caused a decrease in cytosolic NAD+ levels in RAW 264.7 and Maf-DKO macrophages and led to significant downregulation of the glycolytic flux without directly affecting cell viability, proliferation, ATP production capacity or mitochondrial respiratory activity. Concomitant with these differential metabolic changes, the capacity for phagocytic ingestion of particles and also substrate adhesion of macrophages were altered. Depletion of cytoplasmic NAD+ induced cell-morphological changes and impaired early adhesion in phagocytosis of zymosan particles as well as spreading performance. Restoration of NAD+ levels by NAD+, NMN, or NADP+ supplementation reversed the inhibitory effects of FK866. We conclude that direct coupling to local, actin-based, cytoskeletal dynamics is an important aspect of NAD+’s cytosolic role in the regulation of morphofunctional characteristics of macrophages. PMID:24824795

NAMPT-mediated salvage synthesis of NAD+ controls morphofunctional changes of macrophages.

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Gerda Venter

Full Text Available Functional morphodynamic behavior of differentiated macrophages is strongly controlled by actin cytoskeleton rearrangements, a process in which also metabolic cofactors ATP and NAD(H (i.e. NAD+ and NADH and NADP(H (i.e. NADP+ and NADPH play an essential role. Whereas the link to intracellular ATP availability has been studied extensively, much less is known about the relationship between actin cytoskeleton dynamics and intracellular redox state and NAD+-supply. Here, we focus on the role of nicotinamide phosphoribosyltransferase (NAMPT, found in extracellular form as a cytokine and growth factor, and in intracellular form as one of the key enzymes for the production of NAD+ in macrophages. Inhibition of NAD+ salvage synthesis by the NAMPT-specific drug FK866 caused a decrease in cytosolic NAD+ levels in RAW 264.7 and Maf-DKO macrophages and led to significant downregulation of the glycolytic flux without directly affecting cell viability, proliferation, ATP production capacity or mitochondrial respiratory activity. Concomitant with these differential metabolic changes, the capacity for phagocytic ingestion of particles and also substrate adhesion of macrophages were altered. Depletion of cytoplasmic NAD+ induced cell-morphological changes and impaired early adhesion in phagocytosis of zymosan particles as well as spreading performance. Restoration of NAD+ levels by NAD+, NMN, or NADP+ supplementation reversed the inhibitory effects of FK866. We conclude that direct coupling to local, actin-based, cytoskeletal dynamics is an important aspect of NAD+'s cytosolic role in the regulation of morphofunctional characteristics of macrophages.

Small interfering RNA-mediated silencing of nicotinamide phosphoribosyltransferase (NAMPT and lysosomal trafficking regulator (LYST induce growth inhibition and apoptosis in human multiple myeloma cells: A preliminary study

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Ivyna Pau Ni Bong

2016-11-01

Full Text Available Multiple myeloma (MM is a malignancy of B lymphocytes or plasma cells. Our array-based comparative genomic hybridization findings revealed chromosomal gains at 7q22.3 and 1q42.3, where nicotinamide (NAM phosphoribosyltransferase (NAMPT and lysosomal trafficking regulator (LYST genes are localized, respectively. This led us to further study the functions of these genes in myeloma cells. NAMPT is a key enzyme involved in nicotinamide adenine dinucleotide salvage pathway, and it is frequently overexpressed in human cancers. In contrast, little is known about the function of LYST in cancer. The expression of LYST is shown to affect lysosomal size, granule size, and autophagy in human cells. In this study, the effects of small interfering RNA (siRNA-mediated silencing of NAMPT and LYST on cell proliferation and apoptosis were evaluated in RPMI 8226 myeloma cells. Transfection efficiencies were determined by quantitative real time reverse transcriptase PCR. Cell proliferation was determined using MTT assay, while apoptosis was analyzed with flow cytometry using Annexin V-fluorescein isothiocyanate/propidium iodide assay. The NAMPT protein expression in siRNA-treated cells was estimated by enzyme-linked immunosorbent assay. Our results showed that NAMPT and LYST were successfully knockdown by siRNA transfection (p < 0.05. NAMPT or LYST gene silencing significantly inhibited cell proliferation and induced apoptosis in RPMI 8226 cells (p < 0.05. Silencing of NAMPT gene also decreased NAMPT protein levels (p < 0.01. Our study demonstrated that NAMPT and LYST play pivotal roles in the molecular pathogenesis of MM. This is the first report describing the possible functions of LYST in myelomagenesis and its potential role as a therapeutic target in MM.

Small interfering RNA-mediated silencing of nicotinamide phosphoribosyltransferase (NAMPT) and lysosomal trafficking regulator (LYST) induce growth inhibition and apoptosis in human multiple myeloma cells: A preliminary study

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Bong, Ivyna Pau Ni; Ng, Ching Ching; Fakiruddin, Shaik Kamal; Lim, Moon Nian; Zakaria, Zubaidah

2016-01-01

Multiple myeloma (MM) is a malignancy of B lymphocytes or plasma cells. Our array-based comparative genomic hybridization findings revealed chromosomal gains at 7q22.3 and 1q42.3, where nicotinamide (NAM) phosphoribosyltransferase (NAMPT) and lysosomal trafficking regulator (LYST) genes are localized, respectively. This led us to further study the fprotein expression in unctions of these genes in myeloma cells. NAMPT is a key enzyme involved in nicotinamide adenine dinucleotide salvage pathway, and it is frequently overexpressed in human cancers. In contrast, little is known about the function of LYST in cancer. The expression of LYST is shown to affect lysosomal size, granule size, and autophagy in human cells. In this study, the effects of small interfering RNA (siRNA)-mediated silencing of NAMPT and LYST on cell proliferation and apoptosis were evaluated in RPMI 8226 myeloma cells. Transfection efficiencies were determined by quantitative real time reverse transcriptase PCR. Cell proliferation was determined using MTT assay, while apoptosis was analyzed with flow cytometry using Annexin V-fluorescein isothiocyanate/propidium iodide assay. The NAMPT protein expression in siRNA-treated cells was estimated by enzyme-linked immunosorbent assay. Our results showed that NAMPT and LYST were successfully knockdown by siRNA transfection (p < 0.05). NAMPT or LYST gene silencing significantly inhibited cell proliferation and induced apoptosis in RPMI 8226 cells (p < 0.05). Silencing of NAMPT gene also decreased NAMPT protein levels (p < 0.01). Our study demonstrated that NAMPT and LYST play pivotal roles in the molecular pathogenesis of MM. This is the first report describing the possible functions of LYST in myelomagenesis and its potential role as a therapeutic target in MM. PMID:27754828

Deficiency of the iron-sulfur clusters of mitochondrial reduced nicotinamide-adenine dinucleotide-ubiquinone oxidoreductase (complex I) in an infant with congenital lactic acidosis.

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Moreadith, R W; Batshaw, M L; Ohnishi, T; Kerr, D; Knox, B; Jackson, D; Hruban, R; Olson, J; Reynafarje, B; Lehninger, A L

1984-09-01

We report the case of an infant with hypoglycemia, progressive lactic acidosis, an increased serum lactate/pyruvate ratio, and elevated plasma alanine, who had a moderate to profound decrease in the ability of mitochondria from four organs to oxidize pyruvate, malate plus glutamate, citrate, and other NAD+-linked respiratory substrates. The capacity to oxidize the flavin adenine dinucleotide-linked substrate, succinate, was normal. The most pronounced deficiency was in skeletal muscle, the least in kidney mitochondria. Enzymatic assays on isolated mitochondria ruled out defects in complexes II, III, and IV of the respiratory chain. Further studies showed that the defect was localized in the inner membrane mitochondrial NADH-ubiquinone oxidoreductase (complex I). When ferricyanide was used as an artificial electron acceptor, complex I activity was normal, indicating that electrons from NADH could reduce the flavin mononucleotide cofactor. However, electron paramagnetic resonance spectroscopy performed on liver submitochondrial particles showed an almost total loss of the iron-sulfur clusters characteristic of complex I, whereas normal signals were noted for other mitochondrial iron-sulfur clusters. This infant is presented as the first reported case of congenital lactic acidosis caused by a deficiency of the iron-sulfur clusters of complex I of the mitochondrial electron transport chain.

Effect of a mixture of caffeine and nicotinamide on the solubility of vitamin (B2) in aqueous solution.

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Evstigneev, M P; Evstigneev, V P; Santiago, A A Hernandez; Davies, D B

2006-05-01

The effect of caffeine (CAF) and nicotinamide (NMD) on the solubility of a vitamin B2 derivative (FMN) has been evaluated for mixtures containing either a single hydrotrope (CAF or NMD) or the two hydrotropes simultaneously. A model for analysis of ternary systems, which takes into account all possible complexes between the molecules, has been developed and tested with experimental NMR data on the three-component mixture FMN-CAF-NMD. The results indicate that special attention should be given to the concentration of a hydrotropic agent used to enhance the solubility of a particular drug. A decrease in the efficacy of solubility of the vitamin on addition of large amounts of hydrotropic agent is expected in the two-component systems due to the increased proportion of self-association of the hydrotrope. It is found that a mixture of two hydrotropic agents leads to an increase in the solubility of the vitamin in three-component compared to the two-component system. Rather than using just one hydrotropic agent, it is proposed that a strategy for optimising the solubility of aromatic drugs is to use a mixture of hydrotropic agents.

The excimer lamp induces cutaneous nerve degeneration and reduces scratching in a dry-skin mouse model.

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Kamo, Atsuko; Tominaga, Mitsutoshi; Kamata, Yayoi; Kaneda, Kazuyuki; Ko, Kyi C; Matsuda, Hironori; Kimura, Utako; Ogawa, Hideoki; Takamori, Kenji

2014-12-01

Epidermal hyperinnervation, which is thought to underlie intractable pruritus, has been observed in patients with atopic dermatitis (AD). The epidermal expression of axonal guidance molecules has been reported to regulate epidermal hyperinnervation. Previously, we showed that the excimer lamp has antihyperinnervative effects in nonpruritic dry-skin model mice, although epidermal expression of axonal guidance molecules was unchanged. Therefore, we investigated the antipruritic effects of excimer lamp irradiation and its mechanism of action. A single irradiation of AD model mice significantly inhibited itch-related behavior 1 day later, following improvement in the dermatitis score. In addition, irradiation of nerve fibers formed by cultured dorsal root ganglion neurons increased bleb formation and decreased nerve fiber expression of nicotinamide mononucleotide adenylyl transferase 2, suggesting degenerative changes in these fibers. We also analyzed whether attaching a cutoff excimer filter (COF) to the lamp, thus decreasing cytotoxic wavelengths, altered hyperinnervation and the production of cyclobutane pyrimidine dimer (CPD), a DNA damage marker, in dry-skin model mice. Irradiation with COF decreased CPD production in keratinocytes, as well as having an antihyperinnervative effect, indicating that the antipruritic effects of excimer lamp irradiation with COF are due to induction of epidermal nerve degeneration and reduced DNA damage.

Antidiabetic Potential of Kefir Combination from Goat Milk and Soy Milk in Rats Induced with Streptozotocin-Nicotinamide

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Harmayani, Eni; Sunarti

2015-01-01

The study aimed to evaluate the effect of kefir combination from goat milk and soy milk on lipid profile, plasma glucose, glutathione peroxidase (GPx) activity and the improvement of pancreatic β-cell in diabetic rats. Male rats were divided into five treatments: normal control, diabetic control, goat milk kefir, combination of goat milk-soy milk kefir and soy milk kefir. All rats were induced by streptooztocin-nicotinamide (STZ-NA), except for normal control. After 35 d experiment, the rats were sampled for blood, sacrificed and sampled for pancreatic tissues. Results showed that diabetic rats fed kefir combination had higher (p<0.05) triglyceride than the rats fed goat milk or soy milk kefir. Decreasing of plasma glucose in diabetic rats fed kefir combination was higher (p<0.05) than rats fed goat millk kefir. The activity of GPx in diabetic rats fed three kinds of kefir were higher (p<0.01) than untreated diabetic rats. The average number of Langerhans and β-cells in diabetic rats fed kefir combination was the same as the normal control, but it was higher than diabetic control. It was concluded that kefir combination can be used as antidiabetic through maintaining in serum triglyceride, decreasing in plasma glucose, increasing in GPx activity and improving in pancreatic β-cells. PMID:26877646

Nicotinamide phosphoribosyltransferase delays cellular senescence by upregulating SIRT1 activity and antioxidant gene expression in mouse cells.

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Khaidizar, Fiqri D; Nakahata, Yasukazu; Kume, Akira; Sumizawa, Kyosuke; Kohno, Kenji; Matsui, Takaaki; Bessho, Yasumasa

2017-12-01

Senescent cells accumulate in tissues of aged animals and deteriorate tissue functions. The elimination of senescent cells from aged mice not only attenuates progression of already established age-related disorders, but also extends median lifespan. Nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme in mammalian NAD + salvage pathway, has shown a protective effect on cellular senescence of human primary cells. However, it still remains unclear how NAMPT has a protective impact on aging in vitro and in vivo. In this study, we found that primary mouse embryonic fibroblast (MEF) cells undergo progressive decline of NAMPT and NAD + contents during serial passaging before becoming senescent. Furthermore, we showed that constitutive Nampt over-expression increases cellular NAD + content and delays cellular senescence of MEF cells in vitro. We further found that constitutive Nampt over-expression increases SIRT1 activity, increases the expression of antioxidant genes, superoxide dismutase 2 and catalase and promotes resistance against oxidative stress. These findings suggest that Nampt over-expression in MEF cells delays cellular senescence by the mitigation of oxidative stress via the upregulation of superoxide dismutase 2 and catalase gene expressions by SIRT1 activation. © 2017 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.

Nicotinamide supplementation phenocopies SIR2 inactivation by modulating carbon metabolism and respiration during yeast chronological aging.

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Orlandi, Ivan; Pellegrino Coppola, Damiano; Strippoli, Maurizio; Ronzulli, Rossella; Vai, Marina

2017-01-01

Nicotinamide (NAM), a form of vitamin B 3 , is a byproduct and noncompetitive inhibitor of the deacetylation reaction catalyzed by Sirtuins. These represent a family of evolutionarily conserved NAD + -dependent deacetylases that are well-known critical regulators of metabolism and aging and whose founding member is Sir2 of Saccharomyces cerevisiae. Here, we investigated the effects of NAM supplementation in the context of yeast chronological aging, the established model for studying aging of postmitotic quiescent mammalian cells. Our data show that NAM supplementation at the diauxic shift results in a phenocopy of chronologically aging sir2Δ cells. In fact, NAM-supplemented cells display the same chronological lifespan extension both in expired medium and extreme Calorie Restriction. Furthermore, NAM allows the cells to push their metabolism toward the same outcomes of sir2Δ cells by elevating the level of the acetylated Pck1. Both these cells have the same metabolic changes that concern not only anabolic pathways such as an increased gluconeogenesis but also respiratory activity in terms both of respiratory rate and state of respiration. In particular, they have a higher respiratory reserve capacity and a lower non-phosphorylating respiration that in concert with a low burden of superoxide anions can affect positively chronological aging. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Mitochondrial nicotinamide adenine dinucleotide reduced (NADH) oxidation links the tricarboxylic acid (TCA) cycle with methionine metabolism and nuclear DNA methylation.

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Lozoya, Oswaldo A; Martinez-Reyes, Inmaculada; Wang, Tianyuan; Grenet, Dagoberto; Bushel, Pierre; Li, Jianying; Chandel, Navdeep; Woychik, Richard P; Santos, Janine H

2018-04-18

Mitochondrial function affects many aspects of cellular physiology, and, most recently, its role in epigenetics has been reported. Mechanistically, how mitochondrial function alters DNA methylation patterns in the nucleus remains ill defined. Using a cell culture model of induced mitochondrial DNA (mtDNA) depletion, in this study we show that progressive mitochondrial dysfunction leads to an early transcriptional and metabolic program centered on the metabolism of various amino acids, including those involved in the methionine cycle. We find that this program also increases DNA methylation, which occurs primarily in the genes that are differentially expressed. Maintenance of mitochondrial nicotinamide adenine dinucleotide reduced (NADH) oxidation in the context of mtDNA loss rescues methionine salvage and polyamine synthesis and prevents changes in DNA methylation and gene expression but does not affect serine/folate metabolism or transsulfuration. This work provides a novel mechanistic link between mitochondrial function and epigenetic regulation of gene expression that involves polyamine and methionine metabolism responding to changes in the tricarboxylic acid (TCA) cycle. Given the implications of these findings, future studies across different physiological contexts and in vivo are warranted.

Influence of tetrahydrocurcumin on tail tendon collagen contents and its properties in rats with streptozotocin-nicotinamide-induced type 2 diabetes.

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Pari, Leelavinothan; Murugan, Pidaran

2007-12-01

Changes in the structural and functional properties of collagen caused by advanced glycation might be of importance for the etiology of late-stage complications in diabetics. Curcumin is the most active component of turmeric. It is believed that curcumin is a potent antioxidant and anti-inflammatory agent. Tetrahydrocurcumin (THC) is one of the major metabolites of curcumin, exhibiting many of the same physiological and pharmacological activities of curcumin and in some systems may exert greater antioxidant activity than curcumin. In diabetic rats, hydroxyproline and collagen content as well as its degree of cross-linking were increased, as shown by increased extent of glycation, collagen-linked fluorescence, neutral salt collagen, and decreased acid and pepsin solubility. Administration of THC for 45 days to diabetic rats significantly reduced the accumulation and cross-linking of collagen. The effects of THC were comparable with those of curcumin. In conclusion, administration of THC had a positive influence on the content of collagen and its properties in streptozotocin- and nicotinamide-induced diabetic rats. THC was found to be more effective than curcumin.

Nicotinamide impairs entry into and exit from meiosis I in mouse oocytes.

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Riepsamen, Angelique; Wu, Lindsay; Lau, Laurin; Listijono, Dave; Ledger, William; Sinclair, David; Homer, Hayden

2015-01-01

Following exit from meiosis I, mammalian oocytes immediately enter meiosis II without an intervening interphase, accompanied by rapid reassembly of a bipolar spindle that maintains condensed chromosomes in a metaphase configuration (metaphase II arrest). Here we study the effect of nicotinamide (NAM), a non-competitive pan-sirtuin inhibitor, during meiotic maturation in mouse oocytes. Sirtuins are a family of seven NAD+-dependent deacetylases (Sirt1-7), which are involved in multiple cellular processes and are emerging as important regulators in oocytes and embryos. We found that NAM significantly delayed entry into meiosis I associated with delayed accumulation of the Cdk1 co-activator, cyclin B1. GVBD was also inhibited by the Sirt2-specific inhibitor, AGK2, and in a very similar pattern to NAM, supporting the notion that as in somatic cells, NAM inhibits sirtuins in oocytes. NAM did not affect subsequent spindle assembly, chromosome alignment or the timing of first polar body extrusion (PBE). Unexpectedly, however, in the majority of oocytes with a polar body, chromatin was decondensed and a nuclear structure was present. An identical phenotype was observed when flavopiridol was used to induce Cdk1 inactivation during late meiosis I prior to PBE, but not if Cdk1 was inactivated after PBE when metaphase II arrest was already established, altogether indicating that NAM impaired establishment rather than maintenance of metaphase II arrest. During meiosis I exit in NAM-treated medium, we found that cyclin B1 levels were lower and inhibitory Cdk1 phosphorylation was increased compared with controls. Although activation of the anaphase-promoting complex-Cdc20 (APC-Cdc20) occurred on-time in NAM-treated oocytes, Cdc20 levels were higher in very late meiosis I, pointing to exaggerated APC-Cdc20-mediated proteolysis as a reason for lower cyclin B1 levels. Collectively, therefore, our data indicate that by disrupting Cdk1 regulation, NAM impairs entry into meiosis I and

Should carbogen and nicotinamide be given throughout the full course of fractionated radiotherapy regimens?

International Nuclear Information System (INIS)

Rojas, A.M.; Johns, H.; Fiat, P.R.

1993-01-01

Tumor radiosensitization with carbogen and nicotinamide (CON) was compared when both agents were given throughout fractionated radiotherapy with the sensitization observed when administered with only half of the fractions. The effect of overall treatment time on the local control of tumors irradiated in air or with CON was also investigated. Local tumor control of a rodent adenocarcinoma, CaNT, was studied using eight different 20-fraction x-ray regimens. An overall time of either 10 or 20 days was used and CON was given with all, the first half or last half of the treatment. Relative to air, all six sensitizer combinations gave a large and significant increase in sensitization (p much-lt 0.00001). Enhancement ratios were 1.9 and 2.1 when CON was given with all 20 fractions in either 10 or 20 days, respectively. For both overall times, enhancement ratios were reduced by 15-25% when CON was given with only half of the fractions. In air, reducing the treatment time from 20 to 10 days gave a small but significant decrease in the isoeffective doses. When CON was administered with either all or part of a schedule, varying the treatment time had little or no effect on local tumor control. No toxic side-effects were encountered when the sensitizers were administered 10 or 20 times, either once or twice per day. CON is an effective and non-toxic tumor radiosensitizer. In CaNT tumors, a significantly greater effect is seen when CON is given with every fraction of the schedule. The sensitizers reduced or abolished the sparing effect of overall time. 22 refs., 1 fig., 2 tabs

Signal-enhanced electrochemiluminescence immunosensor based on synergistic catalysis of nicotinamide adenine dinucleotide hydride and silver nanoparticles.

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Wang, Guangjie; Jin, Feng; Dai, Nan; Zhong, Zhaoyang; Qing, Yi; Li, Mengxia; Yuan, Ruo; Wang, Dong

2012-03-01

A new metal-organic nanocomposite with synergistic catalysis function was prepared and developed to construct an electrochemiluminescence (ECL) immunosensor for ultrasensitive detection of tumor biomarker CA125. Silver nanoparticles (AgNPs) and nicotinamide adenine dinucleotide hydride (NADH) that can participate and catalyze the ECL reaction of Ru(bpy)(3)(2+) were employed as the metal component and the organic component to synthesize the metal-organic nanocomposite of NADH-AgNPs (NA). The novel ECL immunosensor was assembled via Ru(bpy)(3)(2+)-doped silica nanoparticles (Ru-SiO(2)) modified electrode with the NA as immune labels. First, the chitosan-suspended Ru-SiO(2) nanoparticles were cast on the gold electrode surface to immobilize the ECL probes of Ru(bpy)(3)(2+) and link gold nanoparticles. Then, the primary antibodies were loaded onto the modified electrode via the gold sulfhydryl covalent binding. After immunobinding the analytes of antigen, NA-attached secondary antibodies could be captured as a sandwich type on the electrode. Finally, based on the circularly synergistic catalysis by the silver and NADH for the solid-phase ECL of Ru(bpy)(3)(2+), the proposed immunosensor sensed the concentration of antigen. The synergistic ECL catalysis of metal-organic nanocomposite amplified response signal and pushed the detection limit down to 0.03 U ml(-1), which initiated a new ECL labeling field and has great significance for ECL immunoassays. Copyright © 2012 Elsevier Inc. All rights reserved.

Effects of nicotinamide N-methyltransferase on PANC-1 cells proliferation, metastatic potential and survival under metabolic stress.

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Yu, Tao; Wang, Yong-Tao; Chen, Pan; Li, Yu-Hua; Chen, Yi-Xin; Zeng, Hang; Yu, Ai-Ming; Huang, Min; Bi, Hui-Chang

2015-01-01

Aberrant expression of Nicotinamide N-methyltransferase (NNMT) has been reported in pancreatic cancer. However, the role of NNMT in pancreatic cancer development remains elusive. Therefore, the present study was to investigate the impact of NNMT on pancreatic cancer cell proliferation, metastatic potential and survival under metabolic stress. Pancreatic cancer cell line PANC-1 was transfected with NNMT expression plasmid or small interfering RNA of NNMT to overexpress or knockdown intracellular NNMT expression, respectively. Rate of cell proliferation was monitored. Transwell migration and matrigel invasion assays were conducted to assess cell migration and invasion capacity. Resistance to glucose deprivation, sensitivity to glycolytic inhibition, mitochondrial inhibtion and resistance to rapamycin were examined to evaluate cell survival under metabolic stress. NNMT silencing markedly reduced cell proliferation, whereas NNMT overexpression promoted cell growth moderately. Knocking down NNMT also significantly suppressed the migration and invasion capacities of PANC-1 cells. Conversely, NNMT upregulation enhanced cell migration and invasion capacities. In addition, NNMT knockdown cells were much less resistant to glucose deprivation and rapamycin as well as glycolytic inhibitor 2-deoxyglucose whereas NNMT-expressing cells showed opposite effects although the effects were not so striking. These data sugguest that NNMT plays an important role in PANC-1 cell proliferation, metastatic potential and survival under metabolic stress. © 2015 S. Karger AG, Basel.

Effects of Nicotinamide N-Methyltransferase on PANC-1 Cells Proliferation, Metastatic Potential and Survival Under Metabolic Stress

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Tao Yu

2015-01-01

Full Text Available Background: Aberrant expression of Nicotinamide N-methyltransferase (NNMT has been reported in pancreatic cancer. However, the role of NNMT in pancreatic cancer development remains elusive. Therefore, the present study was to investigate the impact of NNMT on pancreatic cancer cell proliferation, metastatic potential and survival under metabolic stress. Methods: Pancreatic cancer cell line PANC-1 was transfected with NNMT expression plasmid or small interfering RNA of NNMT to overexpress or knockdown intracellular NNMT expression, respectively. Rate of cell proliferation was monitored. Transwell migration and matrigel invasion assays were conducted to assess cell migration and invasion capacity. Resistance to glucose deprivation, sensitivity to glycolytic inhibition, mitochondrial inhibtion and resistance to rapamycin were examined to evaluate cell survival under metabolic stress. Results: NNMT silencing markedly reduced cell proliferation, whereas NNMT overexpression promoted cell growth moderately. Knocking down NNMT also significantly suppressed the migration and invasion capacities of PANC-1 cells. Conversely, NNMT upregulation enhanced cell migration and invasion capacities. In addition, NNMT knockdown cells were much less resistant to glucose deprivation and rapamycin as well as glycolytic inhibitor 2-deoxyglucose whereas NNMT-expressing cells showed opposite effects although the effects were not so striking. Conclusions: These data sugguest that NNMT plays an important role in PANC-1 cell proliferation, metastatic potential and survival under metabolic stress.

One- and Two- Magnon Excitations in a One-Dimensional Antiferromagnet in a Magnetic Field

DEFF Research Database (Denmark)

Heilmann, I.U.; Kjems, Jørgen; Endoh, Y.

1981-01-01

We have carried out a comprehensive experimental and theoretical study of the inelastic scattering in the one-dimensional near-Heisenberg antiferromagnet (CD3)4NMnCl3 (TMMC) at low temperatures, 0.3...

ACCURACY OF PLASMA FREE METANEPHRINES IN THE DIAGNOSIS OF PHEOCHROMOCYTOMA AND PARAGANGLIOMA: A SYSTEMATIC REVIEW AND META-ANALYSIS.

Science.gov (United States)

Chen, Yan; Xiao, Huangmeng; Zhou, Xieda; Huang, Xiaoyu; Li, Yanbing; Xiao, Haipeng; Cao, Xiaopei

2017-10-01

Various studies have validated plasma free metanephrines (MNs) as biomarkers for pheochromocytoma and paraganglioma (PPGL). This meta-analysis aimed to estimate the overall diagnostic accuracy of this biochemical test for PPGL. We searched the PubMed, the Cochrane Library, Web of Science, Embase, Scopus, OvidSP, and ProQuest Dissertations & Theses databases from January 1, 1995 to December 2, 2016 and selected studies written in English that assessed plasma free MNs in the diagnosis of PPGL. Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) was used to evaluate the quality of the included studies. We calculated pooled sensitivities, specificities, positive and negative likelihood ratios, diagnostic odds ratios (DORs) and areas under curve (AUCs) with their 95% confidence intervals (95% CIs). Heterogeneity was assessed by I 2 . To identify the source of heterogeneity, we evaluated the threshold effect and performed a meta-regression. Deeks' funnel plot was selected for investigating any potential publication bias. Although the combination of metanephrine (MN) and normetanephrine (NMN) carried lower specificity (0.94, 95% CI 0.90-0.97) than NMN (0.97, 95% CI 0.92-0.99), NMN was generally more accurate than individual tests, with the highest AUC (0.99, 95% CI 0.97-0.99), DOR (443.35, 95% CI 216.9-906.23), and pooled sensitivity (0.97, 95% CI 0.94-0.98) values. Threshold effect and meta-regression analyses showed that different cut-offs, blood sampling positions, study types and test methods contributed to heterogeneity. This meta-analysis suggested an effective value for combined plasma free MNs for the diagnosis of PPGL, but testing for MNs requires more standardization using tightly regulated studies. AUC = area under curve; CI = confidence interval; DOR = diagnostic odds ratio; EIA = enzyme immunoassay; LC-ECD = liquid chromatography-electrochemical detection; LC-MS/MS = liquid chromatography-tandem mass spectrometry; MN = metanephrine; NMN

Clickable prodrugs bearing potent and hydrolytically cleavable nicotinamide phosphoribosyltransferase inhibitors

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Sadrerafi K

2018-04-01

Full Text Available Keivan Sadrerafi, Emilia O Mason, Mark W Lee Jr Department of Chemistry, University of Missouri, Columbia, MO, USA Purpose: Our previous study indicated that carborane containing small-molecule 1-(hydroxymethyl-7-(4′-(trans-3″-(3‴-pyridylacrylamidobutyl-1,7-dicarbadodecaborane (hm-MC4-PPEA, was a potent inhibitor of nicotinamide phosphoribosyltransferase (Nampt. Nampt has been shown to be upregulated in most cancers and is a promising target for the treatment of many different types of cancers, including breast cancers. Patients and methods: To increase the selectivity of hm-MC4-PPEA toward cancer cells, three prodrugs were synthesized with different hydrolyzable linkers: ester, carbonate, and carbamate. Using click chemistry a fluorophore was attached to these prodrugs to act as a model for our conjugation strategy and to serve as an aid for prodrug stability studies. The stabilities of these drug conjugates were tested in phosphate-buffered saline (PBS at normothermia (37°C using three different pH levels, 5.5, 7.5, and 9.5, as well as in horse serum at physiological pH. The stability of each was monitored using reversed-phase HPLC equipped with both diode array and fluorescence detection. The inhibitory activity of hm-MC4-PPEA was also measured using a commercially available colorimetric assay. The biological activities of the drug conjugates as well as those of the free drug (hm-MC4-PPEA, were evaluated using the MTT assay against the human breast cancer cell lines T47D and MCF7, as well as the noncancerous, transformed, Nampt-dependent human breast epithelium cell line 184A1.Results: hm-MC4-PPEA showed to be a potent inhibitor of recombinant Nampt activity, exhibiting an IC50 concentration of 6.8 nM. The prodrugs showed great stability towards hydrolytic degradation under neutral, mildly acidic and mildly basic conditions. The carbamate prodrug also showed to be stable in rat serum. However, the carbonate and the ester prodrug

Synthesis of oligonucleotide phosphorodithioates

DEFF Research Database (Denmark)

Beaton, G.; Brill, W. K D; Grandas, A.

1991-01-01

The synthesis of DNA containing sulfur at the two nonbonding internucleotide valencies is reported. Several different routes using either tervalent or pentavalent mononucleotide synthons are described.......The synthesis of DNA containing sulfur at the two nonbonding internucleotide valencies is reported. Several different routes using either tervalent or pentavalent mononucleotide synthons are described....

Red algae (Gelidium amansii reduces adiposity via activation of lipolysis in rats with diabetes induced by streptozotocin-nicotinamide

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Tsung-Han Yang

2015-12-01

Full Text Available Gelidium amansii (GA is an edible red algae that is distributed mainly in northeastern Taiwan. This study was designed to investigate the effects of GA on plasma glucose, lipids, and adipocytokines in rats with streptozotocin-nicotinamide-induced diabetes. Rats were divided into four groups: (1 rats without diabetes fed a high-fat diet (control group; (2 rats with diabetes fed a high-fat diet; (3 rats with diabetes fed a high-fat diet with thiazolidinedione in the diet; and (4 rats with diabetes fed a high-fat diet and GA. The experimental diet and drinking water were available ad libitum for 11 weeks. After the 11-week feeding study, plasma glucose, triglyceride, and cholesterol concentrations were lower in rats with diabetes fed the GA diet than in animals with diabetes fed the control diet. In addition, cholesterol and triglyceride excretion were significantly higher in rats with diabetes fed the GA diet. Moreover, GA feeding induced lipolysis in both paraepididymal and perirenal adipose tissues. Adipose tissue (paraepididymal and perirenal weight and triglyceride contents were lower after GA treatment. Plasma adipocytokines including tumor necrosis factor-alpha, interleukin-6, and plasminogen activator inhibitor-1 were reduced by GA feeding in rats with diabetes. The results of the current study suggest that GA feeding may regulate plasma glucose and lipid levels and prevent adipose tissue accumulation in rats with diabetes.

In-line monitoring of cocrystallization process and quantification of carbamazepine-nicotinamide cocrystal using Raman spectroscopy and chemometric tools

Science.gov (United States)

Soares, Frederico L. F.; Carneiro, Renato L.

2017-06-01

A cocrystallization process may involve several molecular species, which are generally solid under ambient conditions. Thus, accurate monitoring of different components that might appear during the reaction is necessary, as well as quantification of the final product. This work reports for the first time the synthesis of carbamazepine-nicotinamide cocrystal in aqueous media with a full conversion. The reactions were monitored by Raman spectroscopy coupled with Multivariate Curve Resolution - Alternating Least Squares, and the quantification of the final product among its coformers was performed using Raman spectroscopy and Partial Least Squares regression. The slurry reaction was made in four different conditions: room temperature, 40 °C, 60 °C and 80 °C. The slurry reaction at 80 °C enabled a full conversion of initial substrates into the cocrystal form, using water as solvent for a greener method. The employment of MCR-ALS coupled with Raman spectroscopy enabled to observe the main steps of the reactions, such as drug dissolution, nucleation and crystallization of the cocrystal. The PLS models gave mean errors of cross validation around 2.0 (% wt/wt), and errors of validation between 2.5 and 8.2 (% wt/wt) for all components. These were good results since the spectra of cocrystals and the physical mixture of the coformers present some similar peaks.

Syntheses, crystal structures and spectroscopic properties of copper(II)-tetracyanometallate(II) complexes with nicotinamide and isonicotinamide ligands

Science.gov (United States)

Sayın, Elvan; Kürkçüoğlu, Güneş Süheyla; Yeşilel, Okan Zafer; Hökelek, Tuncer

2015-09-01

Four new one dimensional (1D) cyanide complexes, namely {[Cu(NH3)4(μ-na)][M‧(CN)4]}n and {[Cu(NH3)2(ina)2M‧(μ-CN)2(CN)2]}n (M‧(II) = Pd (1 and 3) or Pt (2 and 4), na:nicotinamide and ina:isonicotinamide) have been synthesized and characterized by elemental, spectral (FT-IR and Raman), and thermal (TG, DTG and DTA) analyses. The crystal structures of complexes 1-3 have been determined by single crystal X-ray diffraction technique. In complexes 1 and 2, na ligand is coordinated to the adjacent Cu(II) ions as a bridging ligand, giving rise to 1D linear cationic chain and the [M‧(CN)4]2- anionic complex acts as a counter ion. Complexes 3 and 4 are also 1D linear chain in which two cyanide ligands bridged neighboring M‧(II) and Cu(II) ions, while ina ligand is coordinated Cu(II) ion through nitrogen atom of pyridine ring. In the complexes, the Cu(II) ions adopt distorted octahedral geometries, while M‧(II) ions are four coordinated with four carbon atoms from cyanide ligands in square-planar geometries. The adjacent chains are further stacked through intermolecular hydrogen bond, Nsbnd Hṡṡṡπ, Csbnd H⋯M‧ and M‧⋯π interactions to form 3D supramolecular networks. Vibration assignments are given for all the observed bands. In addition, thermal stabilities of the compounds are also discussed.

A preclinical study on the rescue of normal tissue by nicotinic acid in high-dose treatment with APO866, a specific nicotinamide phosphoribosyltransferase inhibitor

DEFF Research Database (Denmark)

Olesen, Uffe Høgh; Thougaard, Annemette V; Jensen, Peter Buhl

2010-01-01

Inhibitor of nicotinamide phosphoribosyltransferase APO866 is a promising cancer drug currently in phase II clinical trials in oncology. Here, we present a strategy for increasing the therapeutic potential of APO866 through the rescue of normal tissues by coadministration of nicotinic acid (Vitamin...... B(3)). We examined the toxicity profile of APO866 in B6D2F1 mice and the effect of oral administration of nicotinic acid on tissue toxicity. Nicotinic acid (50 mg/kg) protects mice from death and severe toxicity from an APO866 dose (60 mg/kg) four times the monotherapy maximum tolerated dose (15 mg....../kg). In a panel of six cancer cell lines, we find that three (including ML-2 cells) are protected by nicotinic acid in vitro, whereas the cytotoxicity of APO866 remains unaffected in the remaining three (including A2780 cells). A selective biomarker for the protection by nicotinic acid was subsequently identified...

Targeting NAD+ metabolism in the human malaria parasite Plasmodium falciparum.

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Jessica K O'Hara

Full Text Available Nicotinamide adenine dinucleotide (NAD+ is an essential metabolite utilized as a redox cofactor and enzyme substrate in numerous cellular processes. Elevated NAD+ levels have been observed in red blood cells infected with the malaria parasite Plasmodium falciparum, but little is known regarding how the parasite generates NAD+. Here, we employed a mass spectrometry-based metabolomic approach to confirm that P. falciparum lacks the ability to synthesize NAD+ de novo and is reliant on the uptake of exogenous niacin. We characterized several enzymes in the NAD+ pathway and demonstrate cytoplasmic localization for all except the parasite nicotinamidase, which concentrates in the nucleus. One of these enzymes, the P. falciparum nicotinate mononucleotide adenylyltransferase (PfNMNAT, is essential for NAD+ metabolism and is highly diverged from the human homolog, but genetically similar to bacterial NMNATs. Our results demonstrate the enzymatic activity of PfNMNAT in vitro and demonstrate its ability to genetically complement the closely related Escherichia coli NMNAT. Due to the similarity of PfNMNAT to the bacterial enzyme, we tested a panel of previously identified bacterial NMNAT inhibitors and synthesized and screened twenty new derivatives, which demonstrate a range of potency against live parasite culture. These results highlight the importance of the parasite NAD+ metabolic pathway and provide both novel therapeutic targets and promising lead antimalarial compounds.

Screening with an NMNAT2-MSD platform identifies small molecules that modulate NMNAT2 levels in cortical neurons.

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Ali, Yousuf O; Bradley, Gillian; Lu, Hui-Chen

2017-03-07

Nicotinamide mononucleotide adenylyl transferase 2 (NMNAT2) is a key neuronal maintenance factor and provides potent neuroprotection in numerous preclinical models of neurological disorders. NMNAT2 is significantly reduced in Alzheimer's, Huntington's, Parkinson's diseases. Here we developed a Meso Scale Discovery (MSD)-based screening platform to quantify endogenous NMNAT2 in cortical neurons. The high sensitivity and large dynamic range of this NMNAT2-MSD platform allowed us to screen the Sigma LOPAC library consisting of 1280 compounds. This library had a 2.89% hit rate, with 24 NMNAT2 positive and 13 negative modulators identified. Western analysis was conducted to validate and determine the dose-dependency of identified modulators. Caffeine, one identified NMNAT2 positive-modulator, when systemically administered restored NMNAT2 expression in rTg4510 tauopathy mice to normal levels. We confirmed in a cell culture model that four selected positive-modulators exerted NMNAT2-specific neuroprotection against vincristine-induced cell death while four selected NMNAT2 negative modulators reduced neuronal viability in an NMNAT2-dependent manner. Many of the identified NMNAT2 positive modulators are predicted to increase cAMP concentration, suggesting that neuronal NMNAT2 levels are tightly regulated by cAMP signaling. Taken together, our findings indicate that the NMNAT2-MSD platform provides a sensitive phenotypic screen to detect NMNAT2 in neurons.

Mass spectrometric quantification of salivary metanephrines-A study in healthy subjects

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Osinga, Thamara E.; Horst-Schrivers, van der Anouk N. A.; van Faassen, Martijn; Kerstens, Michiel N.; Dullaart, Robin P. F.; Pacak, Karel; Links, Thera P.; Kema, Ido P.

Background: Determination of metanephrine (MN), normetanephrine (NMN), and 3-methoxytyramine (3-MT) in saliva may offer potential diagnostic advantages in diagnosing pheochromocytoma. Methods: In this preliminary study, we determined metanephrine concentrations in saliva of healthy subjects and the

Unilateral and Bilateral Adrenalectomy for Pheochromocytoma Requires Adjustment of Urinary and Plasma Metanephrine Reference Ranges

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Osinga, Thamara E.; van den Eijnden, Maartje H. A.; Kema, Ido P.; Kerstens, Michiel N.; Dullaart, Robin P. F.; de Jong, Wilhelmina H. A.; Sluiter, Wim J.; Links, Thera P.; van der Horst-Schrivers, Anouk N. A.

Context: Follow-up after adrenalectomy for pheochromocytoma is recommended because of a recurrence risk. During follow-up, plasma and/or urinary metanephrine (MN) and normetanephrine (NMN) are interpreted using reference ranges obtained in healthy subjects. Objective: Because adrenalectomy may

Crystal structure and Hirshfeld surface analysis of aqua-bis-(nicotinamide-κN)bis-(4-sulfamoylbenzoato-κO1)copper(II).

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Hökelek, Tuncer; Yavuz, Vijdan; Dal, Hakan; Necefoğlu, Hacali

2018-01-01

In the crystal of the title complex, [Cu(C 7 H 6 NO 4 S) 2 (C 6 H 6 N 2 O) 2 (H 2 O)], the Cu II cation and the O atom of the coordinated water mol-ecule reside on a twofold rotation axis. The Cu II ion is coordinated by two carboxyl-ate O atoms of the two symmetry-related 4-sulfamoylbenzoate (SB) anions and by two N atoms of the two symmetry-related nicotinamide (NA) mol-ecules at distances of 1.978 (2) and 2.025 (3) Å, respectively, forming a slightly distorted square-planar arrangement. The distorted square-pyramidal coordination environment is completed by the water O atom in the axial position at a distance of 2.147 (4) Å. In the crystal, the mol-ecules are linked via O-H⋯O and N-H⋯O hydrogen bonds with R 2 2 (8) and R 2 2 (18) ring motifs, forming a three-dimensional architecture. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯O/O⋯H (42.2%), H⋯H (25.7%) and H⋯C/C⋯H (20.0%) inter-actions.

Cofactor balance by nicotinamide nucleotide transhydrogenase (NNT) coordinates reductive carboxylation and glucose catabolism in the tricarboxylic acid (TCA) cycle.

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Gameiro, Paulo A; Laviolette, Laura A; Kelleher, Joanne K; Iliopoulos, Othon; Stephanopoulos, Gregory

2013-05-03

Cancer and proliferating cells exhibit an increased demand for glutamine-derived carbons to support anabolic processes. In addition, reductive carboxylation of α-ketoglutarate by isocitrate dehydrogenase 1 (IDH1) and 2 (IDH2) was recently shown to be a major source of citrate synthesis from glutamine. The role of NAD(P)H/NAD(P)(+) cofactors in coordinating glucose and glutamine utilization in the tricarboxylic acid (TCA) cycle is not well understood, with the source(s) of NADPH for the reductive carboxylation reaction remaining unexplored. Nicotinamide nucleotide transhydrogenase (NNT) is a mitochondrial enzyme that transfers reducing equivalents from NADH to NADPH. Here, we show that knockdown of NNT inhibits the contribution of glutamine to the TCA cycle and activates glucose catabolism in SkMel5 melanoma cells. The increase in glucose oxidation partially occurred through pyruvate carboxylase and rendered NNT knockdown cells more sensitive to glucose deprivation. Importantly, knocking down NNT inhibits reductive carboxylation in SkMel5 and 786-O renal carcinoma cells. Overexpression of NNT is sufficient to stimulate glutamine oxidation and reductive carboxylation, whereas it inhibits glucose catabolism in the TCA cycle. These observations are supported by an impairment of the NAD(P)H/NAD(P)(+) ratios. Our findings underscore the role of NNT in regulating central carbon metabolism via redox balance, calling for other mechanisms that coordinate substrate preference to maintain a functional TCA cycle.

Red algae (Gelidium amansii) reduces adiposity via activation of lipolysis in rats with diabetes induced by streptozotocin-nicotinamide.

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Yang, Tsung-Han; Yao, Hsien-Tsung; Chiang, Meng-Tsan

2015-12-01

Gelidium amansii (GA) is an edible red algae that is distributed mainly in northeastern Taiwan. This study was designed to investigate the effects of GA on plasma glucose, lipids, and adipocytokines in rats with streptozotocin-nicotinamide-induced diabetes. Rats were divided into four groups: (1) rats without diabetes fed a high-fat diet (control group); (2) rats with diabetes fed a high-fat diet; (3) rats with diabetes fed a high-fat diet with thiazolidinedione in the diet; and (4) rats with diabetes fed a high-fat diet and GA. The experimental diet and drinking water were available ad libitum for 11 weeks. After the 11-week feeding study, plasma glucose, triglyceride, and cholesterol concentrations were lower in rats with diabetes fed the GA diet than in animals with diabetes fed the control diet. In addition, cholesterol and triglyceride excretion were significantly higher in rats with diabetes fed the GA diet. Moreover, GA feeding induced lipolysis in both paraepididymal and perirenal adipose tissues. Adipose tissue (paraepididymal and perirenal) weight and triglyceride contents were lower after GA treatment. Plasma adipocytokines including tumor necrosis factor-alpha, interleukin-6, and plasminogen activator inhibitor-1 were reduced by GA feeding in rats with diabetes. The results of the current study suggest that GA feeding may regulate plasma glucose and lipid levels and prevent adipose tissue accumulation in rats with diabetes. Copyright © 2015. Published by Elsevier B.V.

Validation of an assay for quantification of free normetanephrine, metanephrine and methoxytyramine in plasma by high performance liquid chromatography with coulometric detection: Comparison of peak-area vs. peak-height measurements.

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Nieć, Dawid; Kunicki, Paweł K

2015-10-01

Measurements of plasma concentrations of free normetanephrine (NMN), metanephrine (MN) and methoxytyramine (MTY) constitute the most diagnostically accurate screening test for pheochromocytomas and paragangliomas. The aim of this article is to present the results from a validation of an analytical method utilizing high performance liquid chromatography with coulometric detection (HPLC-CD) for quantifying plasma free NMN, MN and MTY. Additionally, peak integration by height and area and the use of one calibration curve for all batches or individual calibration curve for each batch of samples was explored as to determine the optimal approach with regard to accuracy and precision. The method was validated using charcoal stripped plasma spiked with solutions of NMN, MN, MTY and internal standard (4-hydroxy-3-methoxybenzylamine) with the exception of selectivity which was evaluated by analysis of real plasma samples. Calibration curve performance, accuracy, precision and recovery were determined following both peak-area and peak-height measurements and the obtained results were compared. The most accurate and precise method of calibration was evaluated by analyzing quality control samples at three concentration levels in 30 analytical runs. The detector response was linear over the entire tested concentration range from 10 to 2000pg/mL with R(2)≥0.9988. The LLOQ was 10pg/mL for each analyte of interest. To improve accuracy for measurements at low concentrations, a weighted (1/amount) linear regression model was employed, which resulted in inaccuracies of -2.48 to 9.78% and 0.22 to 7.81% following peak-area and peak-height integration, respectively. The imprecisions ranged from 1.07 to 15.45% and from 0.70 to 11.65% for peak-area and peak-height measurements, respectively. The optimal approach to calibration was the one utilizing an individual calibration curve for each batch of samples and peak-height measurements. It was characterized by inaccuracies ranging from -3

Improvement of Nicotinic Acid and Nicotinamide Analysis in Meats and Meat Products by HPLC and LC-MS/MS with Solid-Phase Extraction.

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Hiki, Asako; Yamajima, Yukiko; Uematsu, Yoko

2016-01-01

A method for nicotinic acid (NA) and nicotinamide (NAA) analysis in meats was developed. NA and NAA were extracted from meats or meat products with metaphosphate aqueous solution. The extract was cleaned up with an Oasis MCX cartridge. The cartridge was washed with 2% acetic acid (v/v) and acetic acid-methanol solution. NA and NAA were eluted with ammonia-methanol solution. NA and NAA in the eluate were chromatographed on a Scherzo SM-C18 (3.0×150 mm, 3.0 μm) column with 20 mmol/L ammonium acetate containing 0.1% acetic acid-acetonitrile (97 : 3) as a mobile phase and were monitored at 261 nm. Quantification was performed by LC and LC-MS/MS. Calibration curves showed high linearity (correlation coefficient>0.998) between 1-25 μg/mL for LC and LC-MS/MS. Recoveries were 84-108% (CV≦5.8%) by HPLC and 79-105% (CV≦9.0%) by LC-MS/MS. The limit of quantitation for NA was 0.005-0.01 g/kg and that for NAA was 0.01-0.02 g/kg.

Evaluation of the glycemic effect of Ceratonia siliqua pods (Carob on a streptozotocin-nicotinamide induced diabetic rat model

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Mousa A. Qasem

2018-05-01

Full Text Available Background Ceratonia siliqua pods (carob have been nominated to control the high blood glucose of diabetics. In Yemen, however, its antihyperglycemic activity has not been yet assessed. Thus, this study evaluated the in vitro inhibitory effect of the methanolic extract of carob pods against α-amylase and α-glucosidase and the in vivo glycemic effect of such extract in streptozotocin-nicotinamide induced diabetic rats. Methods 2,2-diphenyl-1-picrylhydrazyl (DPPH and Ferric reducing antioxidant power assay (FRAP were applied to evaluate the antioxidant activity of carob. In vitro cytotoxicity of carob was conducted on human hepatocytes (WRL68 and rat pancreatic β-cells (RIN-5F. Acute oral toxicity of carob was conducted on a total of 18 male and 18 female Sprague-Dawley (SD rats, which were subdivided into three groups (n = 6, namely: high and low dose carob-treated (CS5000 and CS2000, respectively as well as the normal control (NC receiving a single oral dose of 5,000 mg kg−1 carob, 2,000 mg kg−1 carob and 5 mL kg−1 distilled water for 14 days, respectively. Alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, total bilirubin, creatinine and urea were assessed. Livers and kidneys were harvested for histopathology. In vitro inhibitory effect against α-amylase and α-glucosidase was evaluated. In vivo glycemic activity was conducted on 24 male SD rats which were previously intraperitoneally injected with 55 mg kg−1 streptozotocin (STZ followed by 210 mg kg−1nicotinamide to induce type 2 diabetes mellitus. An extra non-injected group (n = 6 was added as a normal control (NC. The injected-rats were divided into four groups (n = 6, namely: diabetic control (D0, 5 mg kg−1glibenclamide-treated diabetic (GD, 500 mg kg−1 carob-treated diabetic (CS500 and 1,000 mg kg−1 carob-treated diabetic (CS1000. All groups received a single oral daily dose of their treatment for 4 weeks. Body weight, fasting blood

Design and discovery of thioether and nicotinamide containing sorafenib analogues as multikinase inhibitors targeting B-Raf, B-RafV600E and VEGFR-2.

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Sun, Shaofeng; He, Zuopeng; Huang, Mindong; Wang, Ningning; He, Zongzhong; Kong, Xiangkai; Yao, Jianwen

2018-04-03

New sorafenib derivatives containing thioether and nicotinamide moiety were designed and synthesized as B-Raf, B-Raf V600E and VEGFR-2 multikinase inhibitors. Their in vitro enzymatic inhibitory activities against B-Raf, B-Raf V600E and VEGFR-2 and their antiproliferative activities against HCT-116 and B16BL6 cell lines were evaluated and described. Most of the compounds showed potent activities against both cell lines and specific kinases. Compounds a1, b1 and c4, which exhibited the most potent inhibitory activities against B-Raf with IC 50 of 21 nM, 27 nM and 17 nM, B-Raf V600E with IC 50 of 29 nM, 28 nM and 16 nM, VEGFR-2 with IC 50 of 84 nM, 46 nM and 63 nM, respectively, and good antiproliferative activities, also demonstrated competitive antiangiogenic activities to sorafenib in in vitro HUVEC tube formation assay. Copyright © 2018 Elsevier Ltd. All rights reserved.

Wear Particles Promote Reactive Oxygen Species-Mediated Inflammation via the Nicotinamide Adenine Dinucleotide Phosphate Oxidase Pathway in Macrophages Surrounding Loosened Implants

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Weishen Chen

2015-03-01

Full Text Available Background/Aims: Prosthesis loosening is closely associated with chronic inflammatory cytokine secretion by macrophages, which are activated by wear particles or inflammatory stimulants such as lipopolysaccharide (LPS. Reactive oxygen species (ROS are critical regulators of inflammation, but their enzymatic sources in response to wear particles and their effects on peri-implant LPS-tolerance remain unclear. Methods: Three ROS-related enzymes—nicotinamide adenine dinucleotide phosphate oxidase (NOX-1 and -2 and catalase—were investigated in interface membrane tissues and in titanium (Ti particle-stimulated macrophages in vitro. The generation of ROS and downstream inflammatory effects were measured with or without pre-incubation with apocynin, an NOX inhibitor. Results: Pre-exposure to Ti particles attenuated NF-κB activation in LPS-stimulated macrophages, indicating that wear particles suppress immune response, which may lead to chronic inflammation. NOX-1 and -2 were highly expressed in aseptically loosened interface membranes and in macrophages stimulated with Ti particles; the particles induced a moderate amount of ROS generation, NF-κB activation, and TNF-a secretion in macrophages, and these effects were suppressed by apocynin. Conclusion: Wear particles induce ROS generation through the NOX signaling pathway, resulting in persistent inflammation and delayed loosening. Thus, the suppression of NOX activity may be a useful strategy for preventing prosthesis loosening.

Nicotinamide augments the survival and incidence of apoptosis in glioma cells following photodynamic therapy in vitro

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Bisland, Stuart K.; Modi, Nayan; Wilson, Brian C.

2004-10-01

The ability to customize photodynamic therapy (PDT) parameters with regards to timing and dosing of administered drug and light can be beneficial in determining target specificity and mode of cell death. Sustained, low level PDT or metronomic PDT (mPDT) may afford enhanced apoptotic cell death. This is of particular importance when considering PDT for the treatment of brain tumors as unlike apoptosis, necrotic cell death often leads to inflammation with increased intracranial pressure. The ability, therefore, to 'fine tune' PDT in favour of apoptosis is paramount. We have studied both acute (one time treatment) PDT (aPDT) and mPDT delivery strategies in combination with nicotinamide (NA) in an attempt to maximize the number of tumor cells dieing by apoptosis. Using several different glioma cell lines (9L, U87-MG and CNS-1) we now confirm that NA provides a dose-dependent (0.1-0.5 mM) increase in apoptotic cells following d-aminolevulinic acid-mediated aPDT or mPDT. Furthermore, using the 9L cell line stably transfected with the luciferase gene, NA was shown to delay the depletion of bioluminscence signal in aPDT and mPDT treated cells, inferring that adenosine triphosphate levels are maintained for longer following NA treatment. NA has previously been reported as promoting neuronal and vascular cell survival in normal brain following a number of neurological insults in which reactive oxygen species are implicated including, stroke, Alzheimer's disease and toxin-induced lesions. It is likely that the effects of NA reflect its capacity as an antioxidant as well as its ability to inhibit poly (adenosine diphosphate-ribose) polymerase-mediated depletion of ATP. Our results indicate that NA may prove therapeutically advantageous when used in combination with PDT treatment of brain tumors.

Cofactor Balance by Nicotinamide Nucleotide Transhydrogenase (NNT) Coordinates Reductive Carboxylation and Glucose Catabolism in the Tricarboxylic Acid (TCA) Cycle*♦

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Gameiro, Paulo A.; Laviolette, Laura A.; Kelleher, Joanne K.; Iliopoulos, Othon; Stephanopoulos, Gregory

2013-01-01

Cancer and proliferating cells exhibit an increased demand for glutamine-derived carbons to support anabolic processes. In addition, reductive carboxylation of α-ketoglutarate by isocitrate dehydrogenase 1 (IDH1) and 2 (IDH2) was recently shown to be a major source of citrate synthesis from glutamine. The role of NAD(P)H/NAD(P)+ cofactors in coordinating glucose and glutamine utilization in the tricarboxylic acid (TCA) cycle is not well understood, with the source(s) of NADPH for the reductive carboxylation reaction remaining unexplored. Nicotinamide nucleotide transhydrogenase (NNT) is a mitochondrial enzyme that transfers reducing equivalents from NADH to NADPH. Here, we show that knockdown of NNT inhibits the contribution of glutamine to the TCA cycle and activates glucose catabolism in SkMel5 melanoma cells. The increase in glucose oxidation partially occurred through pyruvate carboxylase and rendered NNT knockdown cells more sensitive to glucose deprivation. Importantly, knocking down NNT inhibits reductive carboxylation in SkMel5 and 786-O renal carcinoma cells. Overexpression of NNT is sufficient to stimulate glutamine oxidation and reductive carboxylation, whereas it inhibits glucose catabolism in the TCA cycle. These observations are supported by an impairment of the NAD(P)H/NAD(P)+ ratios. Our findings underscore the role of NNT in regulating central carbon metabolism via redox balance, calling for other mechanisms that coordinate substrate preference to maintain a functional TCA cycle. PMID:23504317

Protective effect of nicotinamide adenine dinucleotide (NAD+) against spinal cord ischemia-reperfusion injury via reducing oxidative stress-induced neuronal apoptosis.

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Xie, Lei; Wang, Zhenfei; Li, Changwei; Yang, Kai; Liang, Yu

2017-02-01

As previous studies demonstrate that oxidative stress and apoptosis play crucial roles in ischemic pathogenesis and nicotinamide adenine dinucleotide (NAD + ) treatment attenuates oxidative stress-induced cell death among primary neurons and astrocytes as well as significantly reduce cerebral ischemic injury in rats. We used a spinal cord ischemia injury (SCII) model in rats to verify our hypothesis that NAD + could ameliorate oxidative stress-induced neuronal apoptosis. Adult male rats were subjected to transient spinal cord ischemia for 60min, and different doses of NAD + were administered intraperitoneally immediately after the start of reperfusion. Neurological function was determined by Basso, Beattie, Bresnahan (BBB) scores. The oxidative stress level was assessed by superoxide dismutase (SOD) activity and malondialdehyde (MDA) content. The degree of apoptosis was analyzed by deoxyuridinetriphosphate nick-end labeling (TUNEL) staining and protein levels of cleaved caspase-3 and AIF (apoptosis inducing factor). The results showed that NAD + at 50 or 100mg/kg significantly decreased the oxidative stress level and neuronal apoptosis in the spinal cord of ischemia-reperfusion rats compared with saline, as accompanied with the decreased oxidative stress, NAD + administration significantly restrained the neuronal apoptosis after ischemia injury while improved the neurological and motor function. These findings suggested that NAD + might protect against spinal cord ischemia-reperfusion via reducing oxidative stress-induced neuronal apoptosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Antidiabetic, hypolipidemic and hepatoprotective effects of Arctium lappa root’s hydro-alcoholic extract on nicotinamide-streptozotocin induced type 2 model of diabetes in male mice

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Akram Ahangarpour

2017-02-01

Full Text Available Objective: Arctium lappa (burdock, (A. lappa root has hypoglycemic and antioxidative effects, and has been used for treatment of diabetes in tradition medicine. This study was conducted to evaluate the antidiabetic and hypolipidemic properties of A. lappa root extract on nicotinamide-streptozotocin (NA-STZ-induced type2 diabetes in mice.Materials and Methods: In this investigation, 70 adult male NMRI mice (30-35g randomly divided into 7 groups (n=10 as follow: 1-control, 2-type 2 diabetic mice, 3-diabetic mice that received glibenclamide (0.25 mg/kg as an anti-diabetic drug, 4, 5, 6 and 7- diabetic and normal animals that were pre-treated with 200 and 300 mg/kg A. lappa root extract, respectively, for 28 days. Diabetes has been induced by intraperitoneal injection of NA and STZ. Finally, the blood sample was taken and insulin, glucose, SGOT, SGPT, alkaline phosphatase, leptin and lipid levels was evaluated.Results: Induction of diabetes decreased the level of insulin, leptin and high density lipoprotein (HDL and increased the level of other lipids, glucose, and hepatic enzymes significantly (p

Production and purification of avian antibodies (IgYs from inclusion bodies of a recombinant protein central in NAD+ metabolism

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Paula A. Moreno-González

2013-08-01

Full Text Available The use of hens for the production of polyclonal antibodies reduces animal intervention and moreover yields a higher quantity of antibodies than other animal models.  The phylogenetic distance between bird and mammal antigens, often leads to more specific avian antibodies than their mammalian counterparts.Since a large amount of antigen is required for avian antibody production, the use of recombinant proteins for this procedure has been growing faster over the last years. Nevertheless, recombinant protein production through heterologous systems frequently prompts the protein to precipitate, forming insoluble aggregates of limited utility (inclusion bodies. A methodology for the production of avian polyclonal antibodies, using recombinant protein from inclusion bodies is presented in this article.In order to produce the antigen, a recombinant Nicotinamide mononucleotide adenylyltransferase from Giardia intestinalis (His-GiNMNAT was expressed in Escherichia coli.  The protein was purified through solubilization from inclusion bodies prior to its renaturalization.  Antibodies were purified from egg yolk of immunized hens by water dilution, followed by ammonium sulfate precipitation and thiophilic affinity chromatography.The purified antibodies were tested against His-GiNMNAT protein in Western blot essays. From one egg yolk, 14.4 mg of highly pure IgY were obtained; this antibody was able to detect 15ng of His-GiNMNAT.  IgY specificity was improved by means of antigen affinity purification, allowing its use for parasite protein recognition.

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; Young, S.I.; Ho, S.K.; Mizura, S.S. Pertanika 1988, 11, 39. 5. Fogg, A.G.; Summan, A.M. Analyst 1985, 108, 691. 6. Lindquist, J.; Farroha, S.M. Analyst 1975, 100, 377. 7. Wekesa, N.M.N.; Chhabra, S.C.; Thairu, H.M. Bull. Chem. Soc. Ethiop.

Crystal structure and Hirshfeld surface analysis of aqua­bis­(nicotinamide-κN)bis­(4-sulfamoylbenzoato-κO 1)copper(II)

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Hökelek, Tuncer; Yavuz, Vijdan; Dal, Hakan; Necefoğlu, Hacali

2018-01-01

In the crystal of the title complex, [Cu(C7H6NO4S)2(C6H6N2O)2(H2O)], the CuII cation and the O atom of the coordinated water mol­ecule reside on a twofold rotation axis. The CuII ion is coordinated by two carboxyl­ate O atoms of the two symmetry-related 4-sulfamoylbenzoate (SB) anions and by two N atoms of the two symmetry-related nicotinamide (NA) mol­ecules at distances of 1.978 (2) and 2.025 (3) Å, respectively, forming a slightly distorted square-planar arrangement. The distorted square-pyramidal coordination environment is completed by the water O atom in the axial position at a distance of 2.147 (4) Å. In the crystal, the mol­ecules are linked via O—H⋯O and N—H⋯O hydrogen bonds with R 2 2(8) and R 2 2(18) ring motifs, forming a three-dimensional architecture. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯O/O⋯H (42.2%), H⋯H (25.7%) and H⋯C/C⋯H (20.0%) inter­actions. PMID:29416889

Article Commentary: Kynurenine Pathway Pathologies: Do Nicotinamide and Other Pathway Co-Factors have a Therapeutic Role in Reduction of Symptom Severity, Including Chronic Fatigue Syndrome (CFS and Fibromyalgia (FM

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Adele Blankfield

2013-01-01

Full Text Available Chronic fatigue syndrome (CFS and fibromyalgia (FM appear to meet the criteria of a tryptophan-kynurenine pathway disorder with potential neuroimmunological sequelae. Aspects of some of the putative precipitating factors have been previously outlined. 2 , 3 An analysis of the areas of metabolic dysfunction will focus on future directions for research and management. The definition of dual tryptophan pathways has increased the understanding of the mind-body, body-mind dichotomy. The serotonergic pathway highlights the primary (endogenous psychiatric disorders. The up-regulation of the kynurenine pathway by physical illnesses can cause neuropathic and immunological disorders 1 associated with secondary neuropsychiatric symptoms. Tryptophan and nicotinamide deficiencies fall within the protein energy malnutrition (PEM spectrum. They can arise if the kynurenine pathway is stressed by primary or secondary inflammatory conditions and the consequent imbalance of available catabolic/anabolic substrates may adversely influence convalescent phase efficiency. The replacement of depleted or reduced NAD+ levels and other cofactors can perhaps improve the clinical management of these disorders.

Antidiabetic and protective effects of the aqueous extract of Arbutus unedo L. in streptozotocin-nicotinamide-induced diabetic mice.

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Mrabti, Hanae Naceiri; Sayah, Karima; Jaradat, Nidal; Kichou, Faouzi; Ed-Dra, Abdelaziz; Belarj, Badiaa; Cherrah, Yahia; Faouzi, My El Abbes

2018-02-21

Background Diabetes mellitus (DM) is currently a major health problem and the most common chronic disease worldwide. Traditional medicinal plants remedies remain a potential adjunct therapy to maintain better glycemic control while also imparting few side-effects. Arbutus unedo L. has been traditionally used to manage several diseases including diabetes. This study was undertaken to contribute the validation of the traditional use of Arbutus unedoL. (Ericaceae) in the treatment of diabetes. Methods In-vitro antidiabetic effect of the A. unedo roots aqueous extract was conducted using α-glucosidase and α-amylase assays. While in-vivo antidiabetic activity was conducted using streptozotocin-nicotinamide (STZ-NA) induced diabetic mice. Diabetic animals were orally administered the aqueous extract in 500 mg/kg of body weight to assess the antidiabetic effect. The blood glucose level and body weight of the experimental animals were monitored for 4 weeks. In addition, the histopathological examination of the treated mice pancreas was also conducted to observe the changes of β-cells during the treatment process. Results The extract produced a significant decrease in blood glucose level in diabetic mice. This decrease was equivalent to that which observed in mice treated with a standard after 2-4 weeks. In addition, the plant extract exhibited a potent inhibitory effect on α-amylase and α-glucosidase activity with IC50 values of 730.15±0.25 μg/mL and 94.81±5.99 μg/mL, respectively. Moreover, the histopathologic examination of the pancreas showed a restoration of normal pancreatic islet cell architecture which observed in the diabetic mice treated with plant extract. Conclusions The aqueous A. unedo roots extract has a significant in vitro and in vivo antidiabetic effects and improves metabolic alterations. The revealed results justify its traditional medicinal use.

Requirement of a Functional Flavin Mononucleotide Prenyltransferase for the Activity of a Bacterial Decarboxylase in a Heterologous Muconic Acid Pathway in Saccharomyces cerevisiae.

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Weber, Heike E; Gottardi, Manuela; Brückner, Christine; Oreb, Mislav; Boles, Eckhard; Tripp, Joanna

2017-05-15

Biotechnological production of cis , cis -muconic acid from renewable feedstocks is an environmentally sustainable alternative to conventional, petroleum-based methods. Even though a heterologous production pathway for cis , cis -muconic acid has already been established in the host organism Saccharomyces cerevisiae , the generation of industrially relevant amounts of cis , cis -muconic acid is hampered by the low activity of the bacterial protocatechuic acid (PCA) decarboxylase AroY isomeric subunit C iso (AroY-C iso ), leading to secretion of large amounts of the intermediate PCA into the medium. In the present study, we show that the activity of AroY-C iso in S. cerevisiae strongly depends on the strain background. We could demonstrate that the strain dependency is caused by the presence or absence of an intact genomic copy of PAD1 , which encodes a mitochondrial enzyme responsible for the biosynthesis of a prenylated form of the cofactor flavin mononucleotide (prFMN). The inactivity of AroY-C iso in strain CEN.PK2-1 could be overcome by plasmid-borne expression of Pad1 or its bacterial homologue AroY subunit B (AroY-B). Our data reveal that the two enzymes perform the same function in decarboxylation of PCA by AroY-C iso , although coexpression of Pad1 led to higher decarboxylase activity. Conversely, AroY-B can replace Pad1 in its function in decarboxylation of phenylacrylic acids by ferulic acid decarboxylase Fdc1. Targeting of the majority of AroY-B to mitochondria by fusion to a heterologous mitochondrial targeting signal did not improve decarboxylase activity of AroY-C iso , suggesting that mitochondrial localization has no major impact on cofactor biosynthesis. IMPORTANCE In Saccharomyces cerevisiae , the decarboxylation of protocatechuic acid (PCA) to catechol is the bottleneck reaction in the heterologous biosynthetic pathway for production of cis , cis -muconic acid, a valuable precursor for the production of bulk chemicals. In our work, we demonstrate

Antidiabetic, hypolipidemic and hepatoprotective effects of Arctium lappa root's hydro-alcoholic extract on nicotinamide-streptozotocin induced type 2 model of diabetes in male mice.

Science.gov (United States)

Ahangarpour, Akram; Heidari, Hamid; Oroojan, Ali Akbar; Mirzavandi, Farhang; Nasr Esfehani, Khalil; Dehghan Mohammadi, Zeinab

2017-01-01

Arctium lappa (burdock), (A. lappa) root has hypoglycemic and antioxidative effects, and has been used for treatment of diabetes in tradition medicine. This study was conducted to evaluate the antidiabetic and hypolipidemic properties of A. lappa root extract on nicotinamide-streptozotocin (NA-STZ)-induced type2 diabetes in mice. In this investigation, 70 adult male NMRI mice (30-35g) randomly divided into 7 groups (n=10) as follow: 1-control, 2-type 2 diabetic mice, 3-diabetic mice that received glibenclamide (0.25 mg/kg) as an anti-diabetic drug, 4, 5, 6 and 7- diabetic and normal animals that were pre-treated with 200 and 300 mg/kg A. lappa root extract, respectively, for 28 days. Diabetes has been induced by intraperitoneal injection of NA and STZ. Finally, the blood sample was taken and insulin, glucose, SGOT, SGPT, alkaline phosphatase, leptin and lipid levels was evaluated. Induction of diabetes decreased the level of insulin, leptin and high density lipoprotein (HDL) and increased the level of other lipids, glucose, and hepatic enzymes significantly (plappa root extract, at specific doses, has an anti-diabetic effect through its hypolipidemic and insulinotropic properties. Hence, this plant extract may be beneficial in the treatment of diabetes.

Coadministration of alloxan and nicotinamide in rats produces biochemical changes in blood and pathological alterations comparable to the changes in type II diabetes mellitus.

Science.gov (United States)

Vattam, K K; Raghavendran, Hrb; Murali, M R; Savatey, H; Kamarul, T

2016-08-01

In the present study, thirty six male Sprague Dawley rats were randomly divided into six groups and were injected with varying doses of alloxan (Ax) and nicotinamide (NA). The serum levels of glucose, insulin, and adiponectin were measured weekly up to 4 weeks. Elevated levels of glucose were observed in all groups on days 7, 14, 21, and 28, except in groups a and f (control). The serum insulin levels were significantly elevated in groups b and c on day 7, when compared with that in group f, whereas a decrease in the serum insulin levels was observed in groups d and e on days 21 and 28. The adiponectin levels showed inconsistencies on days 7 and 14. However, significant decrease in the adiponectin levels was observed on days 21 and 28. Histological section of the pancreas showed mild (group a), moderate (group b) to severe (groups c, d, and e) degenerative changes. Concomitant fatty changes in the liver and inflammatory infiltration of the kidney were markedly observed in all the treated groups, when compared to control. These results suggested that the use of selective combination of Ax120 + NA50 injection demonstrated type II diabetes mellitus in rats. © The Author(s) 2015.

High Valence, Normal Valence and Unknown Valence

DEFF Research Database (Denmark)

Morsing, Thorbjørn Juul

the serendipitous synthesis of the nitrido-bridged [Rh(en)3]2- [(CN)5MnNMn(CN)5]. The complex anion have previously been studied in the form of the mixed Rb4Na2-salt. In this earlier study, the nitrido-bridge was found to be asymmetrical with the axial ligands in an eclipsed formation. The complex was described...... the [Rh(en)3]2-salt is best described as Mn3.5/Mn3.5. This means that the [(CN)5MnNMn(CN)5]6􀀀 ion displays crystal packing induced oxidation state isomerism, a rare phenomenon. Chapter 4 details the synthesis and characterisation of group 9 dithiolene complexes with focus on the hitherto unknown...... homoleptic iridium dithiolene complexes. When the complexes [M(mnt)3]3􀀀, M = Rh and Co are chemically oxidized, they decompose to yield dinuclear complexes with the metal still in oxidation state III. This is not the case for the corresponding Ir complex which can be oxidized and the oxidation...

Measurement of tritiated norepinephrine metabolism in intact rat brain

International Nuclear Information System (INIS)

Levitt, M.; Kowalik, S.; Barkai, A.I.

1983-01-01

A procedure for the study of NE metabolism in the intact rat brain is described. The method involves ventriculocisternal perfusion of the adult male rat with artificial CSF containing [ 3 H]NE. Radioactivity in the perfusate associated with NE and its metabolites 3,4-dihydroxymandelic acid (DOMA), 3,4-dihydroxphenylethyleneglycol (DHPG), 3-methoxy-4-hydroxymandelic acid (VMA), 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG), and normetanephrine (NMN) is separated using high-performance liquid chromatography (HPLC). After 80 min the radioactivity in the perfusate reaches an apparent steady-state. Analysis of the steady-state samples shows higher activity in the fractions corresponding to DHPG and MHPG than in those corresponding to DOMA and VMA, confirming glycol formation as the major pathway of NE metabolism in rat brain. Pretreatment with an MAO inhibitor (tranylcypromine) results in a marked decrease in the deaminated metabolites DHPG and MHPG and a concurrent increase in NMN. The results indicate this to be a sensitive procedure for the in vivo determination of changes in NE metabolism. (Auth.)

Nrt1 and Tna1-independent export of NAD+ precursor vitamins promotes NAD+ homeostasis and allows engineering of vitamin production.

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Peter Belenky

2011-05-01

Full Text Available NAD(+ is both a co-enzyme for hydride transfer enzymes and a substrate of sirtuins and other NAD(+ consuming enzymes. NAD(+ biosynthesis is required for two different regimens that extend lifespan in yeast. NAD(+ is synthesized from tryptophan and the three vitamin precursors of NAD(+: nicotinic acid, nicotinamide and nicotinamide riboside. Supplementation of yeast cells with NAD(+ precursors increases intracellular NAD(+ levels and extends replicative lifespan. Here we show that both nicotinamide riboside and nicotinic acid are not only vitamins but are also exported metabolites. We found that the deletion of the nicotinamide riboside transporter, Nrt1, leads to increased export of nicotinamide riboside. This discovery was exploited to engineer a strain to produce high levels of extracellular nicotinamide riboside, which was recovered in purified form. We further demonstrate that extracellular nicotinamide is readily converted to extracellular nicotinic acid in a manner that requires intracellular nicotinamidase activity. Like nicotinamide riboside, export of nicotinic acid is elevated by the deletion of the nicotinic acid transporter, Tna1. The data indicate that NAD(+ metabolism has a critical extracellular element in the yeast system and suggest that cells regulate intracellular NAD(+ metabolism by balancing import and export of NAD(+ precursor vitamins.

Microsatellites in the Eukaryotic DNA Mismatch Repair Genes as Modulators of Evolutionary Mutation Rate

Science.gov (United States)

Chang, Dong Kyung; Metzgar, David; Wills, Christopher; Boland, C. Richard

2003-01-01

All "minor" components of the human DNA mismatch repair (MMR) system-MSH3, MSH6, PMS2, and the recently discovered MLH3-contain mononucleotide microsatellites in their coding sequences. This intriguing finding contrasts with the situation found in the major components of the DNA MMR system-MSH2 and MLH1-and, in fact, most human genes. Although eukaryotic genomes are rich in microsatellites, non-triplet microsatellites are rare in coding regions. The recurring presence of exonal mononucleotide repeat sequences within a single family of human genes would therefore be considered exceptional.

Rho-kinase inhibitor and nicotinamide adenine dinucleotide phosphate oxidase inhibitor prevent impairment of endothelium-dependent cerebral vasodilation by acute cigarette smoking in rats.

Science.gov (United States)

Iida, Hiroki; Iida, Mami; Takenaka, Motoyasu; Fukuoka, Naokazu; Dohi, Shuji

2008-06-01

We previously reported that acute cigarette smoking can cause a dysfunction of endothelium-dependent vasodilation in cerebral vessels, and that blocking the angiotensin II (Ang II) type 1 (AT1) receptor with valsartan prevented this impairment. Our aim was to investigate the effects of a Rho-kinase inhibitor (fasudil) and a Nicotinamide Adenine Dinucleotide PHosphate (NADPH) oxidase inhibitor (apocynin) on smoking-induced endothelial dysfunction in cerebral arterioles. In Sprague-Dawley rats, we used a closed cranial window preparation to measure changes in pial vessel diameters following topical acetylcholine (ACh) before smoking. After one-minute smoking, we again examined the arteriolar responses to ACh. Finally, after intravenous fasudil or apocynin pre-treatment we re-examined the vasodilator responses to topical ACh (before and after cigarette smoking). Under control conditions, cerebral arterioles were dose-dependently dilated by topical ACh (10(-6) M and 10(-5) M). One hour after a one-minute smoking (1 mg-nicotine cigarette), 10(-5) M ACh constricted cerebral arterioles. However, one hour after a one-minute smoking, 10(-5) M ACh dilated cerebral pial arteries both in the fasudil pre-treatment and the apocynin pre-treatment groups, responses that were significantly different from those obtained without fasudil or apocynin pre-treatment. Thus, inhibition of Rho-kinase and NADPH oxidase activities may prevent the above smoking-induced impairment of endothelium-dependent vasodilation.

Radiosensitizers action on Iodine 131 therapeutical effect

International Nuclear Information System (INIS)

Agote, Marcos; Kreimann, Erica L.; Bocanera, Laura V.; Dagrosa, Maria A.; Juvenal, Guillermo J.; Pisarev, Mario A.

1999-01-01

Present studies were aimed to research the possible application of a radiosensitizer, nicotinamide, to increase the therapeutical effect of radioiodine. There were used goitrous and normal rats with growing dose of Iodine 131, with and without simultaneous treatment with nicotinamide. The obtained results show that the nicotinamide treatment importantly increases the thyroid radio destructive effect induced by radioiodine. Under these experimental conditions, nicotinamide induces to a significant increase of thyroid vascularisation, without changes in the proteins ADP-ribosylation activity. These results show, for the first time, the radiosensitizer effect of nicotinamide in front of Iodine 131 and give the possibility of using it in the treatment of hyperthyroid or thyroid difference cancer patients. (author)

Metabolic profiling of alternative NAD biosynthetic routes in mouse tissues.

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Valerio Mori

Full Text Available NAD plays essential redox and non-redox roles in cell biology. In mammals, its de novo and recycling biosynthetic pathways encompass two independent branches, the "amidated" and "deamidated" routes. Here we focused on the indispensable enzymes gating these two routes, i.e. nicotinamide mononucleotide adenylyltransferase (NMNAT, which in mammals comprises three distinct isozymes, and NAD synthetase (NADS. First, we measured the in vitro activity of the enzymes, and the levels of all their substrates and products in a number of tissues from the C57BL/6 mouse. Second, from these data, we derived in vivo estimates of enzymes'rates and quantitative contributions to NAD homeostasis. The NMNAT activity, mainly represented by nuclear NMNAT1, appears to be high and nonrate-limiting in all examined tissues, except in blood. The NADS activity, however, appears rate-limiting in lung and skeletal muscle, where its undetectable levels parallel a relative accumulation of the enzyme's substrate NaAD (nicotinic acid adenine dinucleotide. In all tissues, the amidated NAD route was predominant, displaying highest rates in liver and kidney, and lowest in blood. In contrast, the minor deamidated route showed higher relative proportions in blood and small intestine, and higher absolute values in liver and small intestine. Such results provide the first comprehensive picture of the balance of the two alternative NAD biosynthetic routes in different mammalian tissues under physiological conditions. This fills a gap in the current knowledge of NAD biosynthesis, and provides a crucial information for the study of NAD metabolism and its role in disease.

Synthesis, Molecular Docking Studies, In Vitro Antimicrobial and Antifungal Activities of Novel Dipeptide Derivatives Based on N-(2-(2-Hydrazinyl-2-oxoethylamino-2-oxoethyl-Nicotinamide

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Gaber Moustafa

2018-03-01

Full Text Available A series of linear dipeptide derivatives (4–10 were prepared and evaluated as antimicrobial agents via the synthesis of N-(2-(2-hydrazinyl-2-oxoethylamino-2-oxoethyl nicotinamide (4. Compound 4 was reacted with 4-chlorobenzaldehyde or 4-hydroxybenzaldehyde, to give the hydrazones 5 and 6, respectively. On the other hand, Compound 4 was coupled with phenylisocyanate or methylisothiocyanate to give Compounds 7 and 8, respectively. The latter compounds (7 and 8 were coupled with chloroacetic acid to give oxazolidine (9 and thiazolidine (10, respectively. The newly synthesized dipeptide compounds were confirmed by means of their spectral data. The antimicrobial activity of the newly synthesized compounds 4–10 was evaluated by agar well diffusion, and they showed good activity. Compounds 4, 5, and 9 gave the most promising activity in this study. Most of the tested compounds possessed MIC values ranging from 50 to 500 µg/mL. Furthermore, docking studies were carried out on enoyl reductase from E. coli and cytochrome P450 14 α-sterol demethylase (Cyp51 from Candida albicans active sites. The MolDock scores of the seven tested compounds ranged between −117 and −171 and between −107 and −179, respectively.

Antidiabetic, hypolipidemic and hepatoprotective effects of Arctium lappa root’s hydro-alcoholic extract on nicotinamide-streptozotocin induced type 2 model of diabetes in male mice

Science.gov (United States)

Ahangarpour, Akram; Heidari, Hamid; Oroojan, Ali Akbar; Mirzavandi, Farhang; Nasr Esfehani, Khalil; Dehghan Mohammadi, Zeinab

2017-01-01

Objective: Arctium lappa (burdock), (A. lappa) root has hypoglycemic and antioxidative effects, and has been used for treatment of diabetes in tradition medicine. This study was conducted to evaluate the antidiabetic and hypolipidemic properties of A. lappa root extract on nicotinamide-streptozotocin (NA-STZ)-induced type2 diabetes in mice. Materials and Methods: In this investigation, 70 adult male NMRI mice (30-35g) randomly divided into 7 groups (n=10) as follow: 1-control, 2-type 2 diabetic mice, 3-diabetic mice that received glibenclamide (0.25 mg/kg) as an anti-diabetic drug, 4, 5, 6 and 7- diabetic and normal animals that were pre-treated with 200 and 300 mg/kg A. lappa root extract, respectively, for 28 days. Diabetes has been induced by intraperitoneal injection of NA and STZ. Finally, the blood sample was taken and insulin, glucose, SGOT, SGPT, alkaline phosphatase, leptin and lipid levels was evaluated. Results: Induction of diabetes decreased the level of insulin, leptin and high density lipoprotein (HDL) and increased the level of other lipids, glucose, and hepatic enzymes significantly (plappa root extract, at specific doses, has an anti-diabetic effect through its hypolipidemic and insulinotropic properties. Hence, this plant extract may be beneficial in the treatment of diabetes. PMID:28348972

Spectroscopy and Speciation Studies on the Interactions of Aluminum (III with Ciprofloxacin and β-Nicotinamide Adenine Dinucleotide Phosphate in Aqueous Solutions

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Xiaodi Yang

2012-08-01

Full Text Available In this study, both experimental and theoretical approaches, including absorption spectra, fluorescence emission spectra, ¹H- and ³¹P-NMR, electrospray ionization mass spectrometry (ESI-MS, pH-potentiometry and theoretical approaches using the BEST & SPE computer programs were applied to study the competitive complexation between ciprofloxacin (CIP and b-nicotinamide adenine dinucleotide phosphate (NADP with aluminum (III in aqueous solutions. Rank annihilation factor analysis (RAFA was used to analyze the absorption and fluorescence emission spectra of the ligands, the binary complexes and the ternary complexes. It is found, at the mM total concentration level and pH = 7.0, the bidentate mononuclear species [Al(CIP]²⁺ and [Al(NADP] predominate in the aqueous solutions of the Al(III-CIP and Al(III-NADP systems, and the two complexes have similar conditional stability constants. However, the pH-potentiometry results show at the mM total concentration level and pH = 7.0, the ternary species [Al(CIP(HNADP] predominates in the ternary complex system. Comparing predicted NMR spectra with the experimental NMR results, it can be concluded that for the ternary complex, CIP binds to aluminum ion between the 3-carboxylic and 4-carbonyl groups, while the binding site of oxidized coenzyme II is through the oxygen of phosphate, which is linked to adenosine ribose, instead of pyrophosphate. The results also suggested CIP has the potential to be a probe molecular for the detection of NADP and the Al(III-NADP complexes under physiological condition.

An ecofriendly green liquid chromatographic method for simultaneous determination of nicotinamide and clindamycin phosphate in pharmaceutical gel for acne treatment

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Fawzia Ibrahim

2017-07-01

Full Text Available A new green micellar liquid chromatographic method was developed and validated for the quantitative estimation of nicotinamide (NICO and clindamycin phosphate (CLD in bulk and pharmaceutical gel formulation. The analytes are well resolved in less than 6.0 minutes using micellar mobile phase consisting of 0.10M sodium dodecyl sulfate (SDS, 0.3% triethylamine, and 10% 2-propanol in 0.02M orthophosphoric acid at pH 3.0, running through an Eclipse XDB-C8 column (150 mm×4.6 mm, 5 μm particle size with flow rate 1.0 mL/min. The effluent was monitored with diode array detection at 210 nm. The retention times of NICO and CLD were 3.8 minutes and 5.6 minutes, respectively. The method was validated according to the International Conference on Harmonisation (ICH guidelines in terms of linearity, limit of detection, limit of quantification, accuracy, precision, robustness, and specificity to prove its reliability. Linear correlation was achieved by plotting the peak area of each drug against its concentration. It was found to be rectilinear in the ranges of 1.0–40.0 μg/mL and 0.5–15.0 μg/mL with limits of detection of 0.06 μg/mL and 0.03 μg/mL and limits of quantification of 0.19 μg/mL and 0.09 μg/mL for NICO and CLD, respectively. The method was successfully implemented for the simultaneous determination of the analytes in their bulk powder and combined gel formulation with high % recoveries. The ease of sample treatment facilitates and greatly expedites the treatment with reduced cost and improved accuracy of the procedure.

Uptake in the pancreatic islets of nicotimamide, nicotinic acid and tryptophan and their ability to prevent streptozotocin diabetes in mice

Energy Technology Data Exchange (ETDEWEB)

Tjaelve, H; Wilander, E [Uppsala Univ. (Sweden)

1976-01-01

The uptake of the nicotinamide adenine dinucleotide (NAD)-precursors nicotinamide, nicotinic acid and tryptophan in the pancreatic islets of mice was studied by use of autoradio-graphical methods. The ability of these substances to prevent streptozotocin diabetes was studied in the same species. It was found that only nicotinamide was strongly accumulated in the pancreatic islets and nicotinamide was also the only NAD-precursor which protected against the streptozotocin diabetes. Apparently there is a relationship between the ability of the NAD-precursors to be taken up in the pancreatic islets and their ability to prevent streptozotocin diabetes.

Ameliorative Effects of Allium sativum Extract on iNOS Gene Expression and NO Production in Liver of Streptozotocin + Nicotinamide-Induced Diabetic Rats.

Science.gov (United States)

Ziamajidi, Nasrin; Behrouj, Hamid; Abbasalipourkabir, Roghayeh; Lotfi, Fatemeh

2018-04-01

Diabetes mellitus (DM) is one of the most prevalent diseases in the world, which is strongly associated with liver dysfunction. Hyperglycemia, through an oxidative stress pathway, damages various tissues. Herbal medicine is a good candidate to ameliorate hyperglycemia and oxidative stress. In this study, the effects of aqueous Allium sativum (garlic) extract (AGE) on gene expression of inducible nitric oxide synthases (iNOS) and production of nitric oxide (NO) were evaluated in the liver tissue of diabetic rats. Four groups of rats contained normal control rats, garlic control rats (AGE), Streptozotocin (STZ) + nicotinamide-induced diabetic rats (DM), and diabetic rats treated with garlic (DM + AGE). Glucose levels and liver enzymes activities were determined by colorimetric assay in the serum. Gene expression of iNOS by real-time PCR, NO levels by Griess method, oxidative stress parameters by spectrophotometric method and histopathological examination by hematoxylin and eosin staining method were evaluated in the liver tissues. Glucose levels, activities of liver enzymes, oxidative stress markers, iNOS gene expression, and NO production increased significantly in diabetic rats in comparison with control rats, whereas after oral administration of garlic, these parameters decreased significantly, close to the normal levels. Hence, the beneficial effects of garlic on the liver injury of diabetes could be included in the hypoglycaemic and antioxidant properties of garlic via a decrease in gene expression of iNOS and subsequent NO production.

Comparative effects of riboflavin, nicotinamide and folic acid on alveolar bone loss: A morphometric and histopathologic study in rats

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Akpınar Aysun

2016-01-01

Full Text Available Introduction. Periodontitis is a chronic inflammatory and osteolytic disease. Vitamin B complex is a class of water-soluble vitamins that play important roles in cell metabolism. Objective. The aim of this study was to evaluate the effects of riboflavin (RBF, nicotinamide (NA, and folic acid (FA on alveolar bone loss in experimental periodontitis rat model. Methods. Sixty-four male Wistar rats were randomly divided into the following eight groups: Control, Ligated, RBF50 (RBF, 50 mg/kg daily, NA50 (NA, 50 mg/kg daily, FA50 (FA, 50 mg/kg daily, RBF100 (RBF, 100 mg/kg daily, NA100 (NA, 100 mg/kg daily, and FA100 (FA, 100 mg/kg daily. Periodontitis was induced using silk ligature around the right first mandibular molar. After 11 days the rats were sacrificed. Mandible and serum samples were collected. Changes in alveolar bone levels were measured clinically, and periodontal tissues were examined histopathologically. Serum IL-1β (pg/ml levels were analyzed by using ELISA. Results. Mean alveolar bone loss in the mandibular first molar tooth revealed to be significantly lower in RBF100 group than in the Control group. In the Ligated group, alveolar bone loss was significantly higher than in all other groups. The ratio of presence of inflammatory cell infiltration in the Ligated group was significantly higher than in the Control group. The differences in the serum IL-1β levels between the groups were not statistically significant. Osteoclasts that were observed in the Ligated group were significantly higher than those of the Control and FA100 groups. The osteoblastic activity in the Ligated group, RBF100, and NA100 groups were shown to be significantly higher than those in the Control group. Conclusion. This study has demonstrated that systemic administration of RBF, NA, and FA in different dosages (50-100 mg/kg reduced alveolar bone loss in periodontal disease in rats.

β-Nicotinamide adenine dinucleotide acts at prejunctional adenosine A1 receptors to suppress inhibitory musculomotor neurotransmission in guinea pig colon and human jejunum

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Wang, Guo-Du; Wang, Xi-Yu; Liu, Sumei; Xia, Yun; Zou, Fei; Qu, Meihua; Needleman, Bradley J.; Mikami, Dean J.

2015-01-01

Intracellular microelectrodes were used to record neurogenic inhibitory junction potentials in the intestinal circular muscle coat. Electrical field stimulation was used to stimulate intramural neurons and evoke contraction of the smooth musculature. Exposure to β-nicotinamide adenine dinucleotide (β-NAD) did not alter smooth muscle membrane potential in guinea pig colon or human jejunum. ATP, ADP, β-NAD, and adenosine, as well as the purinergic P2Y1 receptor antagonists MRS 2179 and MRS 2500 and the adenosine A1 receptor agonist 2-chloro-N6-cyclopentyladenosine, each suppressed inhibitory junction potentials in guinea pig and human preparations. β-NAD suppressed contractile force of twitch-like contractions evoked by electrical field stimulation in guinea pig and human preparations. P2Y1 receptor antagonists did not reverse this action. Stimulation of adenosine A1 receptors with 2-chloro-N6-cyclopentyladenosine suppressed the force of twitch contractions evoked by electrical field stimulation in like manner to the action of β-NAD. Blockade of adenosine A1 receptors with 8-cyclopentyl-1,3-dipropylxanthine suppressed the inhibitory action of β-NAD on the force of electrically evoked contractions. The results do not support an inhibitory neurotransmitter role for β-NAD at intestinal neuromuscular junctions. The data suggest that β-NAD is a ligand for the adenosine A1 receptor subtype expressed by neurons in the enteric nervous system. The influence of β-NAD on intestinal motility emerges from adenosine A1 receptor-mediated suppression of neurotransmitter release at inhibitory neuromuscular junctions. PMID:25813057

Identification of mitochondrial electron transport chain-mediated NADH radical formation by EPR spin-trapping techniques.

Science.gov (United States)

Matsuzaki, Satoshi; Kotake, Yashige; Humphries, Kenneth M

2011-12-20

The mitochondrial electron transport chain (ETC) is a major source of free radical production. However, due to the highly reactive nature of radical species and their short lifetimes, accurate detection and identification of these molecules in biological systems is challenging. The aim of this investigation was to determine the free radical species produced from the mitochondrial ETC by utilizing EPR spin-trapping techniques and the recently commercialized spin-trap, 5-(2,2-dimethyl-1,3-propoxycyclophosphoryl)-5-methyl-1-pyrroline N-oxide (CYPMPO). We demonstrate that this spin-trap has the preferential quality of having minimal mitochondrial toxicity at concentrations required for radical detection. In rat heart mitochondria and submitochondrial particles supplied with NADH, the major species detected under physiological pH was a carbon-centered radical adduct, indicated by markedly large hyperfine coupling constant with hydrogen (a(H) > 2.0 mT). In the presence of the ETC inhibitors, the carbon-centered radical formation was increased and exhibited NADH concentration dependency. The same carbon-centered radical could also be produced with the NAD biosynthesis precursor, nicotinamide mononucleotide, in the presence of a catalytic amount of NADH. The results support the conclusion that the observed species is a complex I derived NADH radical. The formation of the NADH radical could be blocked by hydroxyl radical scavengers but not SOD. In vitro experiments confirmed that an NADH-radical is readily formed by hydroxyl radical but not superoxide anion, further implicating hydroxyl radical as an upstream mediator of NADH radical production. These findings demonstrate the identification of a novel mitochondrial radical species with potential physiological significance and highlight the diverse mechanisms and sites of production within the ETC.

Wld(S reduces paraquat-induced cytotoxicity via SIRT1 in non-neuronal cells by attenuating the depletion of NAD.

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Qiujing Yu

Full Text Available Wld(S is a fusion protein with NAD synthesis activity, and has been reported to protect axonal and synaptic compartments of neurons from various mechanical, genetic and chemical insults. However, whether Wld(S can protect non-neuronal cells against toxic chemicals is largely unknown. Here we found that Wld(S significantly reduced the cytotoxicity of bipyridylium herbicides paraquat and diquat in mouse embryonic fibroblasts, but had no effect on the cytotoxicity induced by chromium (VI, hydrogen peroxide, etoposide, tunicamycin or brefeldin A. Wld(S also slowed down the death of mice induced by intraperitoneal injection of paraquat. Further studies demonstrated that Wld(S markedly attenuated mitochondrial injury including disruption of mitochondrial membrane potential, structural damage and decline of ATP induced by paraquat. Disruption of the NAD synthesis activity of Wld(S by an H112A or F116S point mutation resulted in loss of its protective function against paraquat-induced cell death. Furthermore, Wld(S delayed the decrease of intracellular NAD levels induced by paraquat. Similarly, treatment with NAD or its precursor nicotinamide mononucleotide attenuated paraquat-induced cytotoxicity and decline of ATP and NAD levels. In addition, we showed that SIRT1 was required for both exogenous NAD and Wld(S-mediated cellular protection against paraquat. These findings suggest that NAD and SIRT1 mediate the protective function of Wld(S against the cytotoxicity induced by paraquat, which provides new clues for the mechanisms underlying the protective function of Wld(S in both neuronal and non-neuronal cells, and implies that attenuation of NAD depletion may be effective to alleviate paraquat poisoning.

Dynamics of particulate phosphorus in a shallow eutrophic lake

Energy Technology Data Exchange (ETDEWEB)

Shinohara, Ryuichiro, E-mail: r-shino@nies.go.jp [National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan); Imai, Akio; Kohzu, Ayato; Tomioka, Noriko [National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan); Furusato, Eiichi [Graduate School of Science and Engineering, Saitama University, 255 Shimo-okubo, Sakura-ku, Saitama 338-8570 (Japan); Satou, Takayuki; Sano, Tomoharu; Komatsu, Kazuhiro; Miura, Shingo; Shimotori, Koichi [National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan)

2016-09-01

We tested the hypothesis that in shallow, eutrophic Lake Kasumigaura, the concentration of particulate phosphorus (PP) is controlled by biogenic P (P in living or dead phytoplankton and bacterial cells), rather than by resuspension of inorganic P in sediment. Increases in wind velocity and turbidity were associated with bottom shear stress exceeding the critical value for the lake (τ{sub c} = 0.15 N m{sup −2}); this increased turbidity was due to sediment resuspension. However, concentrations of PP; HCl-extractable, reactive P in PP (P-rP); and HCl-extractable, non-reactive P in PP (P-nrP) were not correlated with wind velocity (PP vs. wind velocity: r = 0.40, p > 0.05). Rather, the P-nrP concentration accounted for approximately 79% of PP, and the concentrations of PP, P-rP, and P-nrP were correlated with the particulate organic carbon (POC) concentration (POC vs. PP: r = 0.90, p < 0.01; POC vs. P-rP: r = 0.82, p < 0.01; POC vs. P-nrP: r = 0.86, p < 0.01). In our {sup 31}P nuclear magnetic resonance spectroscopy results, mononucleotides accounted for the largest proportion among the detected P compound classes. In addition, concentrations of mononucleotides, orthophosphate, and pyrophosphate were significantly higher in samples with high POC concentrations, whereas the DNA-P concentration was not. These results suggest that biogenic P affects PP concentrations more strongly than does sediment resuspension, and the production of biogenic P creates a pool of mononucleotides, a class of easily degradable P, even in shallow, eutrophic Lake Kasumigaura. - Highlights: • Biogenic P affected the PP concentration more than did sediment resuspension. • PP correlated with particulate organic carbon concentration but not wind velocity. • Mononucleotides accounted for the largest P compound class of organic P in PP.

The distribution of nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) in the medulla oblongata, spinal cord, cranial and spinal nerves of frog, Microhyla ornata.

Science.gov (United States)

Jadhao, Arun G; Biswas, Saikat P; Bhoyar, Rahul C; Pinelli, Claudia

2017-04-01

Nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) enzymatic activity has been reported in few amphibian species. In this study, we report its unusual localization in the medulla oblongata, spinal cord, cranial nerves, spinal nerves, and ganglions of the frog, Microhyla ornata. In the rhombencephalon, at the level of facial and vagus nerves, the NADPH-d labeling was noted in the nucleus of the abducent and facial nerves, dorsal nucleus of the vestibulocochlear nerve, the nucleus of hypoglossus nerve, dorsal and lateral column nucleus, the nucleus of the solitary tract, the dorsal field of spinal grey, the lateral and medial motor fields of spinal grey and radix ventralis and dorsalis (2-10). Many ependymal cells around the lining of the fourth ventricle, both facial and vagus nerves and dorsal root ganglion, were intensely labeled with NADPH-d. Most strikingly the NADPH-d activity was seen in small and large sized motoneurons in both medial and lateral motor neuron columns on the right and left sides of the brain. This is the largest stained group observed from the caudal rhombencephalon up to the level of radix dorsalis 10 in the spinal cord. The neurons were either oval or elongated in shape with long processes and showed significant variation in the nuclear and cellular diameter. A massive NADPH-d activity in the medulla oblongata, spinal cord, and spinal nerves implied an important role of this enzyme in the neuronal signaling as well as in the modulation of motor functions in the peripheral nervous systems of the amphibians. Copyright © 2017 Elsevier B.V. All rights reserved.

The Effects of Probiotic Soymilk Fortified with Omega-3 on Blood Glucose, Lipid Profile, Haematological and Oxidative Stress, and Inflammatory Parameters in Streptozotocin Nicotinamide-Induced Diabetic Rats

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Mohsen Mohammadi Sartang

2015-01-01

Full Text Available Objective. The aim of the present study was to evaluate the effects of probiotic soymilk fortified with omega-3 in diabetic rats. Methods. Soymilk (SM, fermented soymilk (FSM, and fermented soymilk fortified with omega-3 (FSM + omega-3 were prepared. Rats were randomly assigned to five groups of 13 animals per group. Diabetes was induced by a single injection of streptozotocin (STZ 15 min after the intraperitoneal administration of nicotinamide (NA. Normal control (NC and diabetic control (DC rats received 1 mL/day of distilled water and three groups of diabetic rats were given 1 mL/day of SM, FSM, and FSM + omega-3 products by oral gavage for 28 days. Results. Three products significantly (P<0.05 reduced blood glucose, total cholesterol (TC, triglyceride (TG, and malondialdehyde (MDA concentrations compared to the DC group, with the maximum reduction seen in the FSM + omega-3 group. Body weight, red blood cells (RBC, haemoglobin (Hb, haematocrit, and superoxide dismutase (SOD also significantly increased in the FSM + omega-3 group. In the FSM + omega-3 group, MDA level compared with the SM and FSM groups and high sensitivity C-reactive protein (hs-CRP concentrations compared with the DC and FSM groups were significantly lower (P<0.05. Conclusion. Fermented soymilk fortified with omega-3 may be beneficial in diabetes.

Nicotinamide nucleotide transhydrogenase (Nnt) links the substrate requirement in brain mitochondria for hydrogen peroxide removal to the thioredoxin/peroxiredoxin (Trx/Prx) system.

Science.gov (United States)

Lopert, Pamela; Patel, Manisha

2014-05-30

Mitochondrial reactive oxygen species are implicated in the etiology of multiple neurodegenerative diseases, including Parkinson disease. Mitochondria are known to be net producers of ROS, but recently we have shown that brain mitochondria can consume mitochondrial hydrogen peroxide (H2O2) in a respiration-dependent manner predominantly by the thioredoxin/peroxiredoxin system. Here, we sought to determine the mechanism linking mitochondrial respiration with H2O2 catabolism in brain mitochondria and dopaminergic cells. We hypothesized that nicotinamide nucleotide transhydrogenase (Nnt), which utilizes the proton gradient to generate NADPH from NADH and NADP(+), provides the link between mitochondrial respiration and H2O2 detoxification through the thioredoxin/peroxiredoxin system. Pharmacological inhibition of Nnt in isolated brain mitochondria significantly decreased their ability to consume H2O2 in the presence, but not absence, of respiration substrates. Nnt inhibition in liver mitochondria, which do not require substrates to detoxify H2O2, had no effect. Pharmacological inhibition or lentiviral knockdown of Nnt in N27 dopaminergic cells (a) decreased H2O2 catabolism, (b) decreased NADPH and increased NADP(+) levels, and (c) decreased basal, spare, and maximal mitochondrial oxygen consumption rates. Nnt-deficient cells possessed higher levels of oxidized mitochondrial Prx, which rendered them more susceptible to steady-state increases in H2O2 and cell death following exposure to subtoxic levels of paraquat. These data implicate Nnt as the critical link between the metabolic and H2O2 antioxidant function in brain mitochondria and suggests Nnt as a potential therapeutic target to improve the redox balance in conditions of oxidative stress associated with neurodegenerative diseases. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

The active site of oxidative phosphorylation and the origin of hyperhomocysteinemia in aging and dementia.

Science.gov (United States)

McCully, Kilmer S

2015-01-01

The active site of oxidative phosphorylation and adenosine triphosphate (ATP) synthesis in mitochondria is proposed to consist of two molecules of thioretinamide bound to cobalamin, forming thioretinaco, complexed with ozone, oxygen, nicotinamide adenine dinucleotide. and inorganic phosphate, TR2CoO3O2NAD(+)H2PO4(-). Reduction of the pyridinium nitrogen of the nicotinamide group by an electron from electron transport complexes initiates polymerization of phosphate with adenosine diphosphate, yielding nicotinamide riboside and ATP bound to thioretinaco ozonide oxygen. A second electron reduces oxygen to hydroperoxyl radical, releasing ATP from the active site. A proton gradient is created within F1F0 ATPase complexes of mitochondria by reaction of protons with reduced nicotinamide riboside and with hydroperoxyl radical, yielding reduced nicotinamide riboside and hydroperoxide. The hyperhomocysteinemia of aging and dementia is attributed to decreased synthesis of adenosyl methionine by thioretinaco ozonide and ATP, causing decreased allosteric activation of cystathionine synthase and decreased allosteric inhibition of methylenetetrahydrofolate reductase and resulting in dysregulation of methionine metabolism. © 2015 by the Association of Clinical Scientists, Inc.

Effect of telmisartan on the expression of adiponectin receptors and nicotinamide adenine dinucleotide phosphate oxidase in the heart and aorta in type 2 diabetic rats

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Guo Zhixin

2012-08-01

Full Text Available Abstract Background Diabetic cardiovascular disease is associated with decreased adiponectin and increased oxidative stress. This study investigated the effect of telmisartan on the expression of adiponectin receptor 2 (adipoR2 and nicotinamide adenine dinucleotide phosphate (NADPH oxidase subunits in the heart and the expression of adiponectin receptor 1 (adipoR1 in aorta in type 2 diabetic rats. Methods Type 2 diabetes was induced by high-fat and high-sugar diet and intraperitoneal injection of a low dose of streptozotocin (STZ. Heart function, adipoR2, p22phox, NOX4, glucose transporter 4(GLUT4, monocyte chemoattractant protein-1(MCP-1 and connective tissue growth factor (CTGFin the heart, and adipoR1, MCP-1 and nuclear factor kappa B (NF-κB in aorta were analyzed in controls and diabetic rats treated with or without telmisartan (5mg/kg/d by gavage for 12 weeks. Results Heart function, plasma and myocardial adiponectin levels, the expression of myocardial adipoR2 and GLUT4 were significantly decreased in diabetic rats (P Conclusions Our results suggest that telmisartan upregulates the expression of myocardial adiponectin, its receptor 2 and GLUT4. Simultaneously, it downregulates the expression of myocardial p22phox, NOX4, MCP-1, and CTGF, contributing so to the improvement of heart function in diabetic rats. Telmisartan also induces a protective role on the vascular system by upregulating the expression of adipoR1 and downregulating the expression of MCP-1 and NF-κB in the abdominal aorta in diabetic rats.

Superoxide production and expression of NAD(P)H oxidases by transformed and primary human colonic epithelial cells

DEFF Research Database (Denmark)

Perner, A; Andresen, Lars; Pedersen, G

2003-01-01

Superoxide (O(2)(-)) generation through the activity of reduced nicotinamide dinucleotide (NADH) or reduced nicotinamide dinucleotide phosphate (NADPH) oxidases has been demonstrated in a variety of cell types, but not in human colonic epithelial cells....

Antimutagenic activity of oxidase enzymes

International Nuclear Information System (INIS)

Agabeili, R.A.

1986-01-01

By means of a cytogenetic analysis of chromosomal aberrations in plant cells (Welsh onion, wheat) it was found that the cofactors nicotinamide adenine phosphate (NAD), nicotinamide adenine dinucleotide phosphate (NADPH), and riboflavin possess antimutagenic activity

Solid State NMR Characterization of Ibuprofen:Nicotinamide Cocrystals and New Idea for Controlling Release of Drugs Embedded into Mesoporous Silica Particles.

Science.gov (United States)

Skorupska, Ewa; Kaźmierski, Sławomir; Potrzebowski, Marek J

2017-05-01

Grinding and melting methods were employed for synthesis of pharmaceutical cocrystals formed by racemic (R/S) and entiomeric (S) ibuprofen (IBU) and nicotinamide (NA) as coformer. Obtained (R/S)-IBU:NA and (S)-IBU:NA cocrystals were fully characterized by means of advanced one- and two-dimensional solid state nuclear magnetic resonance (SS NMR) techniques with very fast magic angle spinning (MAS) at 60 kHz. The distinction in molecular packing and specific hydrogen bonding pattern was clearly recognized by analysis of 1 H, 13 C, and 15 N spectra. It is concluded from these studies that both methods (grinding and melting) provide exactly the same, specific forms of cocrystals. Thermal solvent-free (TSF) approach was used for loading of (R/S)-IBU:NA and (S)-IBU:NA into the pores of MCM-41 mesoporous silica particle (MSP). The progress and efficiency of this process was analyzed by NMR spectroscopy. It has been confirmed that TSF method is an effective and safe technique of filling the MSP pores with active pharmaceutical ingredients (APIs). By analyzing the NMR results, it has been further proved that excess of IBU and NA components, which are not embedded into the pores during melting and cooling, crystallize on the MCM-41 walls preserving very specific arrangement, characteristic for crystalline samples. By investigating kinetic of release for (R/S)-IBU/MCM-41, (S)-IBU:NA/MCM-41, and (R/S)-IBU:NA/MCM-41 samples containing active components exclusively inside of the pores, it was revealed that release of IBU is much faster for the first of the samples compared to those containing IBU and NA inside the pores. The hypothesis that the rate of release of API can be controlled by specific composition of cocrystal embedded into the MSP pore was further supported by study of (R/S)-IBU:BA/MCM-41 sample with benzoic acid (BA) as coformer.

Defects in Nicotinamide-adenine Dinucleotide Phosphate Oxidase Genes NOX1 and DUOX2 in Very Early Onset Inflammatory Bowel DiseaseSummary

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Patti Hayes

2015-09-01

Full Text Available Background & Aims: Defects in intestinal innate defense systems predispose patients to inflammatory bowel disease (IBD. Reactive oxygen species (ROS generated by nicotinamide-adenine dinucleotide phosphate (NADPH oxidases in the mucosal barrier maintain gut homeostasis and defend against pathogenic attack. We hypothesized that molecular genetic defects in intestinal NADPH oxidases might be present in children with IBD. Methods: After targeted exome sequencing of epithelial NADPH oxidases NOX1 and DUOX2 on 59 children with very early onset inflammatory bowel disease (VEOIBD, the identified mutations were validated using Sanger Sequencing. A structural analysis of NOX1 and DUOX2 variants was performed by homology in silico modeling. The functional characterization included ROS generation in model cell lines and in in vivo transduced murine crypts, protein expression, intracellular localization, and cell-based infection studies with the enteric pathogens Campylobacter jejuni and enteropathogenic Escherichia coli. Results: We identified missense mutations in NOX1 (c.988G>A, p.Pro330Ser; c.967G>A, p.Asp360Asn and DUOX2 (c.4474G>A, p.Arg1211Cys; c.3631C>T, p.Arg1492Cys in 5 of 209 VEOIBD patients. The NOX1 p.Asp360Asn variant was replicated in a male Ashkenazi Jewish ulcerative colitis cohort. Patients with both NOX1 and DUOX2 variants showed abnormal Paneth cell metaplasia. All NOX1 and DUOX2 variants showed reduced ROS production compared with wild-type enzymes. Despite appropriate cellular localization and comparable pathogen-stimulated translocation of altered oxidases, cells harboring NOX1 or DUOX2 variants had defective host resistance to infection with C. jejuni. Conclusions: This study identifies the first inactivating missense variants in NOX1 and DUOX2 associated with VEOIBD. Defective ROS production from intestinal epithelial cells constitutes a risk factor for developing VEOIBD. Keywords: Inflammatory Bowel Disease, NADPH Oxidase

Sympathetic Nerves in Breast Cancer: Angiogenesis and Antiangiogenic Therapy

Science.gov (United States)

2013-02-01

an enzyme found only outside nerve terminals (6). We showed that splenic NE and NMN were markedly elevated 3 days after DMI implantation relative to...daily ISO treatment (Figs. 3A; attached manuscript day x treatment interaction, p = 0.14). To further investigate potential ß-AR-induced effects on...It has high affinity for ß2-AR, but is unable to desensitize ß-AR, resulting in a long-term effectiveness that cannot be achieved with most ß-agonists

Double isotope method for the determination of catecholamines, serotonin, and other amines in the picomole range as their dansyl derivatives

International Nuclear Information System (INIS)

Recasens, M.; Zwiller, J.; Mack, G.; Zanetta, J.P.; Mandel, P.

1977-01-01

A method based on thin-layer chromatographic separation of radioactive products is described for the determination and the quantification of dopamine (DA), noradrenaline (NA), adrenaline (A), normetanephrine (NMN), and serotonin (5HT) in small samples of brain tissue. In this method the amines are converted to [ 14 C]dansyl derivatives by reaction with [ 14 C]dansyl chloride [ 14 C]Dans-Cl) and 3 H-labeled amines are used as internal standards to determine variations in yield

Photolabeling of Glu-129 of the S-1 subunit of pertussis toxin with NAD

Energy Technology Data Exchange (ETDEWEB)

Barbieri, J.T.; Mende-Mueller, L.M.; Rappuoli, R.; Collier, R.J. (Medical College of Wisconsin, Milwaukee (USA))

1989-11-01

UV irradiation was shown to induce efficient transfer of radiolabel from nicotinamide-labeled NAD to a recombinant protein (C180 peptide) containing the catalytic region of the S-1 subunit of pertussis toxin. Incorporation of label from (3H-nicotinamide)NAD was efficient (0.5 to 0.6 mol/mol of protein) relative to incorporation from (32P-adenylate)NAD (0.2 mol/mol of protein). Label from (3H-nicotinamide)NAD was specifically associated with Glu-129. Replacement of Glu-129 with glycine or aspartic acid made the protein refractory to photolabeling with (3H-nicotinamide)NAD, whereas replacement of a nearby glutamic acid, Glu-139, with serine did not. Photolabeling of the C180 peptide with NAD is similar to that observed with diphtheria toxin and exotoxin A of Pseudomonas aeruginosa, in which the nicotinamide portion of NAD is transferred to Glu-148 and Glu-553, respectively, in the two toxins. These results implicate Glu-129 of the S-1 subunit as an active-site residue and a potentially important site for genetic modification of pertussis toxin for development of an acellular vaccine against Bordetella pertussis.

Photolabeling of Glu-129 of the S-1 subunit of pertussis toxin with NAD

International Nuclear Information System (INIS)

Barbieri, J.T.; Mende-Mueller, L.M.; Rappuoli, R.; Collier, R.J.

1989-01-01

UV irradiation was shown to induce efficient transfer of radiolabel from nicotinamide-labeled NAD to a recombinant protein (C180 peptide) containing the catalytic region of the S-1 subunit of pertussis toxin. Incorporation of label from [3H-nicotinamide]NAD was efficient (0.5 to 0.6 mol/mol of protein) relative to incorporation from [32P-adenylate]NAD (0.2 mol/mol of protein). Label from [3H-nicotinamide]NAD was specifically associated with Glu-129. Replacement of Glu-129 with glycine or aspartic acid made the protein refractory to photolabeling with [3H-nicotinamide]NAD, whereas replacement of a nearby glutamic acid, Glu-139, with serine did not. Photolabeling of the C180 peptide with NAD is similar to that observed with diphtheria toxin and exotoxin A of Pseudomonas aeruginosa, in which the nicotinamide portion of NAD is transferred to Glu-148 and Glu-553, respectively, in the two toxins. These results implicate Glu-129 of the S-1 subunit as an active-site residue and a potentially important site for genetic modification of pertussis toxin for development of an acellular vaccine against Bordetella pertussis

Advancing Polymerase Ribozymes Towards Self-Replication

Science.gov (United States)

Tjhung, K. F.; Joyce, G. F.

2017-07-01

Autocatalytic replication and evolution in vitro by (i) a cross-chiral RNA polymerase catalyzing polymerization of mononucleotides of the opposite handedness; (ii) non-covalent assembly of component fragments of an existing RNA polymerase ribozyme.

Formation of RNA phosphodiester bond by histidine-containing dipeptides

DEFF Research Database (Denmark)

Wieczorek, Rafal; Dörr, Mark; Chotera, Agata

2013-01-01

A new scenario for prebiotic formation of nucleic acid oligomers is presented. Peptide catalysis is applied to achieve condensation of activated RNA monomers into short RNA chains. As catalysts, L-dipeptides containing a histidine residue, primarily Ser-His, were used. Reactions were carried out...... in self-organised environment, a water-ice eutectic phase, with low concentrations of reactants. Incubation periods up to 30 days resulted in the formation of short oligomers of RNA. During the oligomerisation, an active intermediate (dipeptide-mononucleotide) is produced, which is the reactive species...... by a transamination mechanism. Because peptides are much more likely products of spontaneous condensation than nucleotide chains, their potential as catalysts for the formation of RNA is interesting from the origin-of-life perspective. Finally, the formation of the dipeptide-mononucleotide intermediate and its...

Epimerization of Alanyl-Alanine Induced by γ-Rays Irradiation in Aqueous Solutions

Science.gov (United States)

Munegumi, Toratane

2017-03-01

Living organisms have homochiral L-amino acids in proteins and homochiral D-mononucleotides in nucleic acids. The chemical evolutionary process to protein homochirality has been discussed for many years. Although many scenarios have been proposed for homochirality in the monomeric compounds, homochirality in amino acids and mononucleotides does not always guarantee homochirality in polypeptides and polynucleotides. Integrated scenarios containing the pathways from monomer to polymer should be proposed because in the pathways oligomers and polymers as well as monomers racemize (or epimerize), degrade, and condense. This research addresses epimerization and degradation of dipeptides under γ-rays irradiation by a cobalt-60 (60Co) radiation source. The different rate constants of epimerization between diastereomeric dipeptides in the research suggest that the potential pathway toward homochirality could be much more complex.

Effects of aqueous extract of Ruta graveolens and its ingredients on cytochrome P450, uridine diphosphate (UDP-glucuronosyltransferase, and reduced nicotinamide adenine dinucleotide (phosphate (NAD(PH-quinone oxidoreductase in mice

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Yune-Fang Ueng

2015-09-01

Full Text Available Ruta graveolens (the common rue has been used for various therapeutic purposes, including relief of rheumatism and treatment of circulatory disorder. To elucidate the effects of rue on main drug-metabolizing enzymes, effects of an aqueous extract of the aerial part of rue and its ingredients on cytochrome P450 (P450/CYP, uridine diphosphate (UDP-glucuronosyltransferase, and reduced nicotinamide adenine dinucleotide (phosphate (NAD(PH:quinone oxidoreductase were studied in C57BL/6JNarl mice. Oral administration of rue extract to males increased hepatic Cyp1a and Cyp2b activities in a dose-dependent manner. Under a 7-day treatment regimen, rue extract (0.5 g/kg induced hepatic Cyp1a and Cyp2b activities and protein levels in males and females. This treatment increased hepatic UDP-glucuronosyltransferase activity only in males. However, NAD(PH:quinone oxidoreductase activity remained unchanged. Based on the contents of rutin and furanocoumarins of mouse dose of rue extract, rutin increased hepatic Cyp1a activity and the mixture of furanocoumarins (Fmix increased Cyp2b activities in males. The mixture of rutin and Fmix increased Cyp1a and Cyp2b activities. These results revealed that rutin and Fmix contributed at least in part to the P450 induction by rue.

MEMS Bragg grating force sensor

DEFF Research Database (Denmark)

Reck, Kasper; Thomsen, Erik Vilain; Hansen, Ole

2011-01-01

We present modeling, design, fabrication and characterization of a new type of all-optical frequency modulated MEMS force sensor based on a mechanically amplified double clamped waveguide beam structure with integrated Bragg grating. The sensor is ideally suited for force measurements in harsh...... environments and for remote and distributed sensing and has a measured sensitivity of -14 nm/N, which is several times higher than what is obtained in conventional fiber Bragg grating force sensors. © 2011 Optical Society of America....

Physiological and biochemical responses of thyme plants to some antioxidants

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SALWA A. ORABI

2014-11-01

Full Text Available Orabi SA, Talaat IM, Balbaa LK. 2014. Physiological and biochemical responses of thyme plants to some antioxidants. Nusantara Bioscience 6: 118-125. Two pot experiments were conducted to investigate the effect of tryptophan, nicotinamide and α-tocopherol (each at 50 and 100 mg/L on plant growth, essential oil yield and its main constituents. All treatments significantly promoted plant height, and increased fresh and dry mass (g/plant of thyme (Thymus vulgaris L.. The treatment with 100 mg/L nicotinamide showed increasing in total potassium mainly in the first cut. Total soluble sugars, oil percentage and oil yield and protein recorded increments with tryptophan treatments. Treatment of Thymus plants with 100 mg/L nicotinamide observed the highest percentage of thymol (67.61%. Oxygenated compounds recorded the highest value with 50 mg/L α-tocopherol treatment, while the maximum non-oxygenated ones resulted from the application of 100 mg/L nicotinamide. All treatments under study significantly affected the activity of oxidoreductase enzymes (POX and PPO. Nicotinamide at the concentration of 100 mg/L recorded the highest increments in APX and GR and the lowest values in oxidoreductase enzyme activities added to the lowest values of lipid peroxidation to enhance the best protection of thyme plants.

Niacin, poly(ADP-ribose) polymerase-1 and genomic stability

NARCIS (Netherlands)

Hageman, G.J.; Stierum, R.H.

2001-01-01

Nicotinic acid (NA) and nicotinamide (NAM), commonly called niacin, are the dietary precursors for NAD+ (nicotinamide adenine dinucleotide), which is required for DNA synthesis, as well as for the activity of the enzyme poly(ADP-ribose) polymerase-1 (PARP-1; EC 2.4.2.30) for which NAD+ is the sole

Poly(ADP-Ribose) Polymerase-1: A Novel Therapeutic Target in Necrotizing Enterocolitis

Science.gov (United States)

Giannone, Peter J.; Alcamo, Alicia A.; Schanbacher, Brandon L.; Nankervis, Craig A.; Besner, Gail E.; Bauer, John A.

2011-01-01

Necrotizing enterocolitis (NEC) is the most common gastrointestinal disease of infancy, afflicting 11% of infants born 22–28 weeks gestational age. Both inflammation and oxidation may be involved in NEC pathogenesis through reactive nitrogen species production, protein oxidation and DNA damage. Poly(ADP-ribose) polymerase-1 (PARP-1) is a critical enzyme activated to facilitate DNA repair using nicotinamide adenine dinucleotide (NAD+) as a substrate. However, in the presence of severe oxidative stress and DNA damage, PARP-1 over-activation may ensue, depleting cells of NAD+ and ATP, killing them by metabolic catastrophe. Here we tested the hypothesis that NO dysregulation in intestinal epithelial cells during NEC leads to marked PARP-1 expression and that administration of a PARP-1 inhibitor (nicotinamide) attenuates intestinal injury in a newborn rat model of NEC. In this model, 56% of control pups developed NEC (any stage), versus 14% of pups receiving nicotinamide. Forty-four percent of control pups developed high-grade NEC (grades 3–4), whereas only 7% of pups receiving nicotinamide developed high-grade NEC. Nicotinamide treatment protects pups against intestinal injury incurred in the newborn rat NEC model. We speculate that PARP-1 over-activation in NEC may drive mucosal cell death in this disease and that PARP-1 may be a novel therapeutic target in NEC. PMID:21399558

Redox Specificity of 2-Hydroxyacid-Coupled NAD+/NADH Dehydrogenases: A Study Exploiting “Reactive” Arginine as a Reporter of Protein Electrostatics

Science.gov (United States)

Durani, Susheel

2013-01-01

With “reactive” arginine as a kinetic reporter, 2-hydroxyacid dehydrogenases are assessed in basis of their specialization as NAD+-reducing or NADH-oxidizing enzymes. Specifically, M4 and H4 lactate dehydrogenases (LDHs) and cytoplasmic and mitochondrial malate dehydrogenases (MDHs) are compared to assess if their coenzyme specificity may involve electrostatics of cationic or neutral nicotinamide structure as the basis. The enzymes from diverse eukaryote and prokaryote sources thus are assessed in “reactivity” of functionally-critical arginine as a function of salt concentration and pH. Electrostatic calculations were performed on “reactive” arginines and found good correspondence with experiment. The reductive and oxidative LDHs and MDHs are assessed in their count over ionizable residues and in placement details of the residues in their structures as proteins. The variants found to be high or low in ΔpKa of “reactive” arginine are found to be also strong or weak cations that preferentially oxidize NADH (neutral nicotinamide structure) or reduce NAD+ (cationic nicotinamide structure). The ionized groups of protein structure may thus be important to redox specificity of the enzyme on basis of electrostatic preference for the oxidized (cationic nicotinamide) or reduced (neutral nicotinamide) coenzyme. Detailed comparisons of isozymes establish that the residues contributing in their redox specificity are scrambled in structure of the reductive enzyme. PMID:24391777

Redox specificity of 2-hydroxyacid-coupled NAD(+/NADH dehydrogenases: a study exploiting "reactive" arginine as a reporter of protein electrostatics.

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Pooja Gupta

Full Text Available With "reactive" arginine as a kinetic reporter, 2-hydroxyacid dehydrogenases are assessed in basis of their specialization as NAD(+-reducing or NADH-oxidizing enzymes. Specifically, M4 and H4 lactate dehydrogenases (LDHs and cytoplasmic and mitochondrial malate dehydrogenases (MDHs are compared to assess if their coenzyme specificity may involve electrostatics of cationic or neutral nicotinamide structure as the basis. The enzymes from diverse eukaryote and prokaryote sources thus are assessed in "reactivity" of functionally-critical arginine as a function of salt concentration and pH. Electrostatic calculations were performed on "reactive" arginines and found good correspondence with experiment. The reductive and oxidative LDHs and MDHs are assessed in their count over ionizable residues and in placement details of the residues in their structures as proteins. The variants found to be high or low in ΔpKa of "reactive" arginine are found to be also strong or weak cations that preferentially oxidize NADH (neutral nicotinamide structure or reduce NAD(+ (cationic nicotinamide structure. The ionized groups of protein structure may thus be important to redox specificity of the enzyme on basis of electrostatic preference for the oxidized (cationic nicotinamide or reduced (neutral nicotinamide coenzyme. Detailed comparisons of isozymes establish that the residues contributing in their redox specificity are scrambled in structure of the reductive enzyme.

Synthesis of a phosphorothioate derivative of flavin mononucleotide

International Nuclear Information System (INIS)

Calhoun, J.P.; Miziorko, H.M.; Otvos, J.D.; Masters, B.S.S.

1987-01-01

The synthesis of riboflavin-5'-phosphorothioate (5'-FMNS), an analog of riboflavin-5'-phosphate (FMN), is described. 5'-FMNS is produced from the alkaline hydrolysis of riboflavin-4',5'-cyclic phosphorothioate (cFMNS). The cyclic phosphorothioate is produced upon reaction of riboflavin with thiophosphoryl chloride in trimethyl phosphate. The phosphorothioate compounds have been characterized by 13 C and 31 P NMR and the purified 5'-FMNS is isolated by preparative HPLC. Preliminary results indicate that this analog of FMN is capable of replacing FMN in at least on flavoprotein, NADPH-cytochrome P-450 reductase, and is competent in reconstituting the cytochrome c reductase activity of this enzyme. Full characterization of this derivatized flavoprotein is in progress

Mononucleotide repeats are asymmetrically distributed in fungal genes

NARCIS (Netherlands)

Passel, van M.W.J.; Graaff, de L.H.

2008-01-01

ABSTRACT: BACKGROUND: Systematic analyses of sequence features have resulted in a better characterisation of the organisation of the genome. A previous study in prokaryotes on the distribution of sequence repeats, which are notoriously variable and can disrupt the reading frame in genes, showed that

Evolutionary appearance of mononucleotide repeats in the coding ...

Indian Academy of Sciences (India)

encompassing 55 million years of evolution, and in humans. The results show that ... The phylogenetic primate DNA panel PRP00001 was obtained through the ... of genomic DNA, 0.2 mM deoxynucleoside triphosphates. (dNTPs), 0.4 /M of ...

galactosidase and α

African Journals Online (AJOL)

phosphate, fructose-6-phosphate, fructose-1- phosphate, α -nicotinamide adenosine dinucleotide (α ..... compared with that of α -nicotinamide adenine dinucleotide (16.3 ± 0.6%) and sodium phytate. (15.2 ± 1.8%) ..... 47: 829–835. Aritajat S., Saenphet K. & Srikalayanukul C., 2005. The toxicity of a crude enzyme extract from.

Association of Nicotinamide Phosphoribosyltransferase (NAMPT Gene Polymorphisms and of Serum NAMPT Levels with Dilated Cardiomyopathy in a Chinese Population

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Qingyu Dou

2015-09-01

Full Text Available Nicotinamide phosphoribosyltransferase (NAMPT has crucial roles for myocardial development, cardiomyocyte energy metabolism and cell death/survival by regulating NAD+-dependent sirtuin-1 (SIRT1 deacetylase. This study aimed to determine if the single nucleotide polymorphisms (SNPs of the NAMPT gene may affect the susceptibility and prognosis for patients with dilated cardiomyopathy (DCM and to describe the association of serum NAMPT levels with clinical features of DCM. Three SNPs (rs61330082, rs2505568, and rs9034 were analyzed by the polymerase chain reaction-restriction fragment length polymorphism method in a case-control study of 394 DCM patients and 395 controls from China. Serum NAMPT levels were measured by enzyme-linked immunosorbent assay kits. The homozygote for the minor allele at rs2505568 and rs9034 could not be detected in this study. Rs9034 T allele and CT genotype were associated with increased DCM risk (OR: 1.63, 95% CI = 1.16–2.27, p = 0.005 and OR: 1.72, 95% CI = 1.20–2.50, p = 0.0027, respectively. Nominally significant decreased DCM risk was found to be associated with the A allele and AT genotype of rs2505568 (OR: 0.48, 95% CI = 0.35–0.67, p < 0.0001 and OR: 0.44, 95% CI = 0.31–0.62, p < 0.0001, respectively, but it should be interpreted with caution because of Hardy-Weinberg disequilibrium in the control group. Of five haplotypes constructed, TAC (rs61330082-rs2505568-rs9034 was a protective haplotype to DCM (OR: 0.22, 95% CI = 0.13–0.39, p = 1.84 × 10−8. The Cox multivariate survival analysis indicated that the rs9034 CT genotype (hazard ratio (HR: 0.59, 95% CI = 0.37–0.96, p = 0.03 was an independently multivariate predictor for longer overall survival in DCM patients. Serum NAMPT levels were significantly higher in the DCM group than controls (p < 0.0001 and gradually increased with the increase of New York Heart Association grade in DCM patients. However, there was a lack of association of the three

Riboflavin carrier protein-targeted fluorescent USPIO for the assessment of vascular metabolism in tumors

NARCIS (Netherlands)

Jayapaul, J.; Arns, S.; Lederle, W.; Lammers, Twan Gerardus Gertudis Maria; Comba, P.; Gätjens, J.; Kiessling, F.

2012-01-01

Abstract Riboflavin (Rf) and its metabolic analogs flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) are essential for normal cellular growth and function. Their intracellular transport is regulated by the riboflavin carrier protein (RCP), which has been shown to be over-expressed by

Nicotinamide Promotes Adipogenesis in Umbilical Cord-Derived Mesenchymal Stem Cells and Is Associated with Neonatal Adiposity: The Healthy Start BabyBUMP Project.

Directory of Open Access Journals (Sweden)

Allison L B Shapiro

Full Text Available The cellular mechanisms whereby excess maternal nutrition during pregnancy increases adiposity of the offspring are not well understood. However, nicotinamide (NAM, a fundamental micronutrient that is important in energy metabolism, has been shown to regulate adipogenesis through inhibition of SIRT1. Here we tested three novel hypotheses: 1 NAM increases the adipogenic response of human umbilical cord tissue-derived mesenchymal stem cells (MSCs through a SIRT1 and PPARγ pathway; 2 lipid potentiates the NAM-enhanced adipogenic response; and 3 the adipogenic response to NAM is associated with increased percent fat mass (%FM among neonates. MSCs were derived from the umbilical cord of 46 neonates born to non-obese mothers enrolled in the Healthy Start study. Neonatal %FM was measured using air displacement plethysmography (Pea Pod shortly after birth. Adipogenic differentiation was induced for 21 days in the 46 MSC sets under four conditions, +NAM (3mM/-lipid (200 μM oleate/palmitate mix, +NAM/+lipid, -NAM/+lipid, and vehicle-control (-NAM/-lipid. Cells incubated in the presence of NAM had significantly higher PPARγ protein (+24%, p <0.01, FABP4 protein (+57%, p <0.01, and intracellular lipid content (+51%, p <0.01. Lipid did not significantly increase either PPARγ protein (p = 0.98 or FABP4 protein content (p = 0.82. There was no evidence of an interaction between NAM and lipid on adipogenic response of PPARγ or FABP4 protein (p = 0.99 and p = 0.09. In a subset of 9 MSC, SIRT1 activity was measured in the +NAM/-lipid and vehicle control conditions. SIRT1 enzymatic activity was significantly lower (-70%, p <0.05 in the +NAM/-lipid condition than in vehicle-control. In a linear model with neonatal %FM as the outcome, the percent increase in PPARγ protein in the +NAM/-lipid condition compared to vehicle-control was a significant predictor (β = 0.04, 95% CI 0.01-0.06, p <0.001. These are the first data to support that chronic NAM exposure

NMNAT1 inhibits axon degeneration via blockade of SARM1-mediated NAD+ depletion

Science.gov (United States)

Sasaki, Yo; Nakagawa, Takashi; Mao, Xianrong; DiAntonio, Aaron; Milbrandt, Jeffrey

2016-01-01

Overexpression of the NAD+ biosynthetic enzyme NMNAT1 leads to preservation of injured axons. While increased NAD+ or decreased NMN levels are thought to be critical to this process, the mechanism(s) of this axon protection remain obscure. Using steady-state and flux analysis of NAD+ metabolites in healthy and injured mouse dorsal root ganglion axons, we find that rather than altering NAD+ synthesis, NMNAT1 instead blocks the injury-induced, SARM1-dependent NAD+ consumption that is central to axon degeneration. DOI: http://dx.doi.org/10.7554/eLife.19749.001 PMID:27735788

Absorption by DNA single strands of adenine isolated in vacuo: The role of multiple chromophores

DEFF Research Database (Denmark)

Nielsen, L.M.; Pedersen, S.O.; Kirketerp, M.-B.S.

2012-01-01

to that for the adenine molecule and the dAMP mononucleotide. Desolvation has little effect on the bandwidth, which implies that inhomogenous broadening of the absorption bands in aqueous solution is of minor importance compared to, e.g., conformational disorder. Finally, at high photon energies, internal conversion...

ADPRT inhibitors and hyperthermia as radiosensitizers

International Nuclear Information System (INIS)

Jonsson, G.G.

1985-01-01

Hyperthermia given in combination with gamma radiation has given considerable improvement in the therapeutic results for treatment of malignant tumors. The mechanism behind the hyperthermia effect is probably operative at the tissue level as well as at the molecular level. The metabolism of NAD + in relation to the activity of the chromosomal enzyme ADP-ribosyl transferase (ADPRT) has been studied as a possible molecular mechanism for this effect. The ADPRT activity was measured after radiosensitization with both hyperthermia and nicotinamide, which is a potent inhibitor of ADPRT. The results indicate that hyperthermia can improve the effect of radiotherapy by reducing the supply of NAD + , which is a co-substrate for ADPRT, while nicotinamide functions as a radiosensitizing agent by direct inhibition of the enzyme. The hypothesis is discussed in the thesis where inhibition of ADPRT might increase the radiosensitivity because the radiation-induced DNA damage can not be repaired with normal efficiency. The function of nicotinamide as a radiosensitizer was verified by studies on C3H mice with transplanted spontaneous mammary tumors. Because nicotinamide is not toxic, it seems quite attractive to test this vitamin as a radiosensitizing agent against human tumors. (251 refs.) (author)

Nicotinamidase activity is important for germination.

Science.gov (United States)

Hunt, Lee; Holdsworth, Michael J; Gray, Julie E

2007-08-01

It has been suggested that nicotinamide must be degraded during germination; however, the enzyme responsible and its physiological role have not been previously studied. We have identified an Arabidopsis gene, NIC2, that is expressed at relatively high levels in mature seed, and encodes a nicotinamidase enzyme with homology to yeast and bacterial nicotinamidases. Seed of a knockout mutant, nic2-1, had reduced nicotinamidase activity, retarded germination and impaired germination potential. nic2-1 germination was restored by after-ripening or moist chilling, but remained hypersensitive to application of nicotinamide or ABA. Nicotinamide is a known inhibitor of NAD-degrading poly(ADP-ribose) polymerases (PARP enzymes) that are implicated in DNA repair. We found reduced poly(ADP)ribosylation levels in nic2-1 seed, which were restored by moist chilling. Furthermore, nic2-1 seed had elevated levels of NAD, and germination was hypersensitive to methyl methanesulphonate (MMS), suggesting that PARP activity and DNA repair responses were impaired. We suggest that nicotinamide is normally metabolized by NIC2 during moist chilling or after-ripening, which relieves inhibition of PARP activity and allows DNA repair to occur prior to germination.

High Resolution Crystal Structures of Streptococcus pneumoniae Nicotinamidase with Trapped Intermediates Provide Insights into Catalytic Mechanism and Inhibition by Aldehydes∥,‡

Science.gov (United States)

French, Jarrod B.; Cen, Yana; Sauve, Anthony A.; Ealick, Steven E.

2010-01-01

Nicotinamidases are salvage enzymes that convert nicotinamide to nicotinic acid. These enzymes are essential for the recycling of nicotinamide into NAD+ in most prokaryotes, most single cell and multicellular eukaryotes, but not in mammals. The significance of these enzymes for nicotinamide salvage and for NAD+ homeostasis has increased interest in nicotinamidases as possible antibiotic targets. Nicotinamidases are also regulators of intracellular nicotinamide concentrations, thereby regulating signaling of downstream NAD+ consuming enzymes, such as the NAD+-dependent deacetylases (sirtuins). Here, we report several high resolution crystal structures of the nicotinamidase from Streptococcus pneumoniae (SpNic) in unliganded and ligand-bound forms. The structure of the C136S mutant in complex with nicotinamide provides details about substrate binding while a trapped nicotinoyl-thioester complexed with SpNic reveals the structure of the proposed thioester reaction intermediate. Examination of the active site of SpNic reveals several important features including a metal ion that coordinates the substrate and the catalytically relevant water molecule, and an oxyanion hole which both orients the substrate and offsets the negative charge that builds up during catalysis. Structures of this enzyme with bound nicotinaldehyde inhibitors elucidate the mechanism of inhibition and provide further details about the catalytic mechanism. In addition, we provide a biochemical analysis of the identity and role of the metal ion that orients the ligand in the active site and activates the water molecule responsible for hydrolysis of the substrate. These data provide structural evidence for several proposed reaction intermediates and allow for a more complete understanding of the catalytic mechanism of this enzyme. PMID:20853856

High-resolution crystal structures of Streptococcus pneumoniae nicotinamidase with trapped intermediates provide insights into the catalytic mechanism and inhibition by aldehydes .

Science.gov (United States)

French, Jarrod B; Cen, Yana; Sauve, Anthony A; Ealick, Steven E

2010-10-12

Nicotinamidases are salvage enzymes that convert nicotinamide to nicotinic acid. These enzymes are essential for the recycling of nicotinamide into NAD(+) in most prokaryotes and most single-cell and multicellular eukaryotes, but not in mammals. The significance of these enzymes for nicotinamide salvage and for NAD(+) homeostasis has stimulated interest in nicotinamidases as possible antibiotic targets. Nicotinamidases are also regulators of intracellular nicotinamide concentrations, thereby regulating signaling of downstream NAD(+)-consuming enzymes, such as the NAD(+)-dependent deacetylases (sirtuins). Here, we report several high-resolution crystal structures of the nicotinamidase from Streptococcus pneumoniae (SpNic) in unliganded and ligand-bound forms. The structure of the C136S mutant in complex with nicotinamide provides details about substrate binding, while a trapped nicotinoyl thioester in a complex with SpNic reveals the structure of the proposed thioester reaction intermediate. Examination of the active site of SpNic reveals several important features, including a metal ion that coordinates the substrate and the catalytically relevant water molecule and an oxyanion hole that both orients the substrate and offsets the negative charge that builds up during catalysis. Structures of this enzyme with bound nicotinaldehyde inhibitors elucidate the mechanism of inhibition and provide further details about the catalytic mechanism. In addition, we provide a biochemical analysis of the identity and role of the metal ion that orients the ligand in the active site and activates the water molecule responsible for hydrolysis of the substrate. These data provide structural evidence of several proposed reaction intermediates and allow for a more complete understanding of the catalytic mechanism of this enzyme.

Structural and kinetic isotope effect studies of nicotinamidase (Pnc1) from Saccharomyces cerevisiae.

Science.gov (United States)

Smith, Brian C; Anderson, Mark A; Hoadley, Kelly A; Keck, James L; Cleland, W Wallace; Denu, John M

2012-01-10

Nicotinamidases catalyze the hydrolysis of nicotinamide to nicotinic acid and ammonia. Nicotinamidases are absent in mammals but function in NAD(+) salvage in many bacteria, yeast, plants, protozoa, and metazoans. We have performed structural and kinetic investigations of the nicotinamidase from Saccharomyces cerevisiae (Pnc1). Steady-state product inhibitor analysis revealed an irreversible reaction in which ammonia is the first product released, followed by nicotinic acid. A series of nicotinamide analogues acting as inhibitors or substrates were examined, revealing that the nicotinamide carbonyl oxygen and ring nitrogen are critical for binding and reactivity. X-ray structural analysis revealed a covalent adduct between nicotinaldehyde and Cys167 of Pnc1 and coordination of the nicotinamide ring nitrogen to the active-site zinc ion. Using this structure as a guide, the function of several residues was probed via mutagenesis and primary (15)N and (13)C kinetic isotope effects (KIEs) on V/K for amide bond hydrolysis. The KIE values of almost all variants were increased, indicating that C-N bond cleavage is at least partially rate limiting; however, a decreased KIE for D51N was indicative of a stronger commitment to catalysis. In addition, KIE values using slower alternate substrates indicated that C-N bond cleavage is at least partially rate limiting with nicotinamide to highly rate limiting with thionicotinamide. A detailed mechanism involving nucleophilic attack of Cys167, followed by elimination of ammonia and then hydrolysis to liberate nicotinic acid, is discussed. These results will aid in the design of mechanism-based inhibitors to target pathogens that rely on nicotinamidase activity.

Structural and Kinetic Isotope Effect Studies of Nicotinamidase (Pnc1) from S. cerevisiae†

Science.gov (United States)

Smith, Brian C.; Anderson, Mark A.; Hoadley, Kelly A.; Keck, James L.; Cleland, W. Wallace; Denu, John M.

2011-01-01

Nicotinamidases catalyze the hydrolysis of nicotinamide to nicotinic acid and ammonia. Nicotinamidases are absent in mammals but function in NAD+ salvage in many bacteria, yeast, plants, protozoa, and metazoans. We have performed structural and kinetic investigations of the nicotinamidase from S. cerevisiae (Pnc1). Steady-state product inhibitor analysis revealed an irreversible reaction where ammonia is the first product released, followed by nicotinic acid. A series of nicotinamide analogs acting as inhibitors or substrates were examined revealing that the nicotinamide carbonyl oxygen and ring nitrogen are critical for binding and reactivity. X-ray structural analysis revealed a covalent adduct between nicotinaldehyde and Cys167 of Pnc1 and coordination of the nicotinamide ring nitrogen to the active-site zinc ion. Using this structure as a guide, the function of several residues was probed via mutagenesis and primary 15N and 13C kinetic isotope effects (KIE) on V/K for amide bond hydrolysis. The KIE values of almost all variants were increased indicating that C-N bond cleavage is at least partially rate limiting; however, a decreased KIE for D51N was observed indicative of a higher commitment to catalysis. In addition, KIE values using slower alternate substrates indicated that C-N bond cleavage is at least partially rate limiting with nicotinamide to highly rate limiting with thionicotinamide. A detailed mechanism is discussed involving nucleophilic attack of Cys167, followed by elimination of ammonia and then hydrolysis to liberate nicotinic acid. These results will aid design of mechanism-based inhibitors to target pathogens that rely on nicotinamidase activity. PMID:22229411

Structural and Kinetic Isotope Effect Studies of Nicotinamidase (Pnc1) from Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Smith, Brian C.; Anderson, Mark A.; Hoadley, Kelly A.; Keck, James L.; Cleland, W. Wallace; Denu, John M.

2012-01-01

Nicotinamidases catalyze the hydrolysis of nicotinamide to nicotinic acid and ammonia. Nicotinamidases are absent in mammals but function in NAD + salvage in many bacteria, yeast, plants, protozoa, and metazoans. We have performed structural and kinetic investigations of the nicotinamidase from Saccharomyces cerevisiae (Pnc1). Steady-state product inhibitor analysis revealed an irreversible reaction in which ammonia is the first product released, followed by nicotinic acid. A series of nicotinamide analogues acting as inhibitors or substrates were examined, revealing that the nicotinamide carbonyl oxygen and ring nitrogen are critical for binding and reactivity. X-ray structural analysis revealed a covalent adduct between nicotinaldehyde and Cys167 of Pnc1 and coordination of the nicotinamide ring nitrogen to the active-site zinc ion. Using this structure as a guide, the function of several residues was probed via mutagenesis and primary 15 N and 13 C kinetic isotope effects (KIEs) on V/K for amide bond hydrolysis. The KIE values of almost all variants were increased, indicating that C-N bond cleavage is at least partially rate limiting; however, a decreased KIE for D51N was indicative of a stronger commitment to catalysis. In addition, KIE values using slower alternate substrates indicated that C-N bond cleavage is at least partially rate limiting with nicotinamide to highly rate limiting with thionicotinamide. A detailed mechanism involving nucleophilic attack of Cys167, followed by elimination of ammonia and then hydrolysis to liberate nicotinic acid, is discussed. These results will aid in the design of mechanism-based inhibitors to target pathogens that rely on nicotinamidase activity.

Determination of B-complex vitamins in pharmaceutical formulations by surface-enhanced Raman spectroscopy

Science.gov (United States)

Junior, Benedito Roberto Alvarenga; Soares, Frederico Luis Felipe; Ardila, Jorge Armando; Durango, Luis Guillermo Cuadrado; Forim, Moacir Rossi; Carneiro, Renato Lajarim

2018-01-01

The aim of this work was to quantify B-complex vitamins in pharmaceutical samples by surface enhanced Raman spectroscopy technique using gold colloid substrate. Synthesis of gold nanoparticles was performed according to an adapted Turkevich method. Initial essays were able to suggest the orientation of molecules on gold nanoparticles surface. Central Composite design was performed to obtain the highest SERS signal for nicotinamide and riboflavin. The evaluated parameters in the experimental design were volume of AuNPs, concentration of vitamins and sodium chloride concentration. The best condition for nicotinamide was NaCl 2.3 × 10- 3 mol L- 1 and 700 μL of AuNPs colloid and this same condition showed to be adequate to quantify thiamine. The experimental design for riboflavin shows the best condition at NaCl 1.15 × 10- 2 mol L- 1 and 2.8 mL of AuNPs colloid. It was possible to quantify thiamine and nicotinamide in presence of others vitamins and excipients in two solid multivitamin formulations using the standard addition procedure. The standard addition curve presented a R2 higher than 0.96 for both nicotinamide and thiamine, at orders of magnitude 10- 7 and 10- 8 mol L- 1, respectively. The nicotinamide content in a cosmetic gel sample was also quantified by direct analysis presenting R2 0.98. The t-student test presented no significant difference regarding HPLC method. Despite the experimental design performed for riboflavin, it was not possible its quantification in the commercial samples.

The Leishmania nicotinamidase is essential for NAD(+) production and parasite proliferation

OpenAIRE

Gazanion, Elodie; Garcia, Deborah; Silvestre, R.; Gérard, C.; Guichou, J. F.; Labesse, G.; Seveno, Martial; Cordeiro-Da-Silva, A.; Ouaissi, A.; Sereno, Denis; Vergnes, Baptiste

2011-01-01

NAD(+) is a central cofactor that plays important roles in cellular metabolism and energy production in all living cells. Genomics-based reconstruction of NAD(+) metabolism revealed that Leishmania protozoan parasites are NAD(+) auxotrophs. Consequently, these parasites require assimilating NAD(+) precursors (nicotinamide, nicotinic acid, nicotinamide riboside) from their host environment to synthesize NAD(+) by a salvage pathway. Nicotinamidase is a key enzyme of this salvage pathway that ca...

Radiosensitizing effects of 9401 on mice bearing H22 hepatoma

International Nuclear Information System (INIS)

Liu Xiaoqiu; Wang Qin; Zhou Zewei; Han Ying; Wang Dezhi; Shen Xiu

2013-01-01

Objective: To investigate the radiosensitizing effects of 9401 on mice bearing H22 hepatoma. Methods: Mouse model bearing H22 hepatoma cells were established. Mice were randomly divided into six groups, the control group,the radiation group and four treatment groups including 9401 at high, medium and low dosages and nicotinamide combined with radiation. After irradiated, the growth of tumor was observed, the time of tumor growth was recorded, the delay time of tumor growth and enhancement factor (EF) were calculated. After 28 days, the mice were killed, the tumors were stripped and inhibition rate was calculated. Results: Groups of 9401 combined with radiation could postpone tumor growth. The difference was statistically significant between 9401 groups at high, medium dosages combined with radiation and nicotinamide combined with radiation group (t=24.7 and 7.5, both P<0.01). Compared with radiation alone group, groups of 9401 combined with radiation had significant radiosensitizing effect. The enhancement factor of 9401 combined with radiation groups at high and medium dosages were 2.13 and 1.73 respectively, they were significant higher than nicotinamide combined with radiation group (t=2.26 and 9.04, both P<0.05). The inhibition rate of 9401 groups at high, medium and low dosages combined with radiation were 64.5%, 50.9% and 42.6% respectively. The inhibition rate of nicotinamide group combined radiation was 53.2%. The inhibition rate of 9401 at high dosage combined with radiation had significant difference with nicotinamide combined radiation (t =2.8, P<0.05). Nicotinamide combined with radiation group, 9401 combined with radiation groups could significant inhibit the growth of tumors compared with radiation alone group (t=5.7, 4.0 and 2.2, all P<0.05). Conclusion: 9401 can inhibit the tumor growth and the inhibition effect increases gradually with the drug dose increasing. It also has radiosensitizing effects on mice bearing H22 hepatoma and present broadly

Equilibrium constant and nitrogen activity and the parameters of interaction eN(N), rN(N,Cr), rN(N,Mn) in high nitrogen steels of Fe-Cr-Mn-N type

International Nuclear Information System (INIS)

Svyazhin, A.G.; Siwka, J.; Rashev, T.

1999-01-01

In the paper a description of a thermodynamic of liquid solutions of Fe-Cr-Mn-N type with using a concept of parameters of an interaction has been presented. A temperature relationship of the equilibrium constant K N(Fe) and values of self interaction parameters e N (N) , r N (N,Cr) , r N (N,Mn) and t N (N,Cr,Cr) has been determined for mean values of temperatures of liquid metal equal 1990 K and 2090 K. By application of a theory of regular solutions those values were recalculated for a temperature 1873 K. (orig.)

Increased Life Span due to Calorie Restriction in Respiratory-Deficient Yeast.

Directory of Open Access Journals (Sweden)

2005-11-01

Full Text Available A model for replicative life span extension by calorie restriction (CR in yeast has been proposed whereby reduced glucose in the growth medium leads to activation of the NAD-dependent histone deacetylase Sir2. One mechanism proposed for this putative activation of Sir2 is that CR enhances the rate of respiration, in turn leading to altered levels of NAD or NADH, and ultimately resulting in enhanced Sir2 activity. An alternative mechanism has been proposed in which CR decreases levels of the Sir2 inhibitor nicotinamide through increased expression of the gene coding for nicotinamidase, PNC1. We have previously reported that life span extension by CR is not dependent on Sir2 in the long-lived BY4742 strain background. Here we have determined the requirement for respiration and the effect of nicotinamide levels on life span extension by CR. We find that CR confers robust life span extension in respiratory-deficient cells independent of strain background, and moreover, suppresses the premature mortality associated with loss of mitochondrial DNA in the short-lived PSY316 strain. Addition of nicotinamide to the medium dramatically shortens the life span of wild type cells, due to inhibition of Sir2. However, even in cells lacking both Sir2 and the replication fork block protein Fob1, nicotinamide partially prevents life span extension by CR. These findings (1 demonstrate that respiration is not required for the longevity benefits of CR in yeast, (2 show that nicotinamide inhibits life span extension by CR through a Sir2-independent mechanism, and (3 suggest that CR acts through a conserved, Sir2-independent mechanism in both PSY316 and BY4742.

High-Resolution Crystal Structures of Streptococcus pneumoniae Nicotinamidase with Trapped Intermediates Provide Insights into the Catalytic Mechanism and Inhibition by Aldehydes

Energy Technology Data Exchange (ETDEWEB)

French, Jarrod B.; Cen, Yana; Sauve, Anthony A.; Ealick, Steven E. (Cornell); (Weill-Med)

2010-11-11

Nicotinamidases are salvage enzymes that convert nicotinamide to nicotinic acid. These enzymes are essential for the recycling of nicotinamide into NAD{sup +} in most prokaryotes and most single-cell and multicellular eukaryotes, but not in mammals. The significance of these enzymes for nicotinamide salvage and for NAD{sup +} homeostasis has stimulated interest in nicotinamidases as possible antibiotic targets. Nicotinamidases are also regulators of intracellular nicotinamide concentrations, thereby regulating signaling of downstream NAD{sup +}-consuming enzymes, such as the NAD{sup +}-dependent deacetylases (sirtuins). Here, we report several high-resolution crystal structures of the nicotinamidase from Streptococcus pneumoniae (SpNic) in unliganded and ligand-bound forms. The structure of the C136S mutant in complex with nicotinamide provides details about substrate binding, while a trapped nicotinoyl thioester in a complex with SpNic reveals the structure of the proposed thioester reaction intermediate. Examination of the active site of SpNic reveals several important features, including a metal ion that coordinates the substrate and the catalytically relevant water molecule and an oxyanion hole that both orients the substrate and offsets the negative charge that builds up during catalysis. Structures of this enzyme with bound nicotinaldehyde inhibitors elucidate the mechanism of inhibition and provide further details about the catalytic mechanism. In addition, we provide a biochemical analysis of the identity and role of the metal ion that orients the ligand in the active site and activates the water molecule responsible for hydrolysis of the substrate. These data provide structural evidence of several proposed reaction intermediates and allow for a more complete understanding of the catalytic mechanism of this enzyme.

Inhibition of Sirt1 promotes neural progenitors toward motoneuron differentiation from human embryonic stem cells

Energy Technology Data Exchange (ETDEWEB)

Zhang, Yun; Wang, Jing [Department of Neurology, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Clinical Stem Cell Center, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Chen, Guian [Clinical Stem Cell Center, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Reproductive Medical Center, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Fan, Dongsheng, E-mail: dsfan@yahoo.cn [Department of Neurology, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Clinical Stem Cell Center, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Deng, Min, E-mail: dengmin1706@yahoo.com.cn [Department of Neurology, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China); Clinical Stem Cell Center, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191 (China)

2011-01-14

Research highlights: {yields} Nicotinamide inhibit Sirt1. {yields} MASH1 and Ngn2 activation. {yields} Increase the expression of HB9. {yields} Motoneurons formation increases significantly. -- Abstract: Several protocols direct human embryonic stem cells (hESCs) toward differentiation into functional motoneurons, but the efficiency of motoneuron generation varies based on the human ESC line used. We aimed to develop a novel protocol to increase the formation of motoneurons from human ESCs. In this study, we tested a nuclear histone deacetylase protein, Sirt1, to promote neural precursor cell (NPC) development during differentiation of human ESCs into motoneurons. A specific inhibitor of Sirt1, nicotinamide, dramatically increased motoneuron formation. We found that about 60% of the cells from the total NPCs expressed HB9 and {beta}III-tubulin, commonly used motoneuronal markers found in neurons derived from ESCs following nicotinamide treatment. Motoneurons derived from ESC expressed choline acetyltransferase (ChAT), a positive marker of mature motoneuron. Moreover, we also examined the transcript levels of Mash1, Ngn2, and HB9 mRNA in the differentiated NPCs treated with the Sirt1 activator resveratrol (50 {mu}M) or inhibitor nicotinamide (100 {mu}M). The levels of Mash1, Ngn2, and HB9 mRNA were significantly increased after nicotinamide treatment compared with control groups, which used the traditional protocol. These results suggested that increasing Mash1 and Ngn2 levels by inhibiting Sirt1 could elevate HB9 expression, which promotes motoneuron differentiation. This study provides an alternative method for the production of transplantable motoneurons, a key requirement in the development of hESC-based cell therapy in motoneuron disease.

Inhibition of Sirt1 promotes neural progenitors toward motoneuron differentiation from human embryonic stem cells

International Nuclear Information System (INIS)

Zhang, Yun; Wang, Jing; Chen, Guian; Fan, Dongsheng; Deng, Min

2011-01-01

Research highlights: → Nicotinamide inhibit Sirt1. → MASH1 and Ngn2 activation. → Increase the expression of HB9. → Motoneurons formation increases significantly. -- Abstract: Several protocols direct human embryonic stem cells (hESCs) toward differentiation into functional motoneurons, but the efficiency of motoneuron generation varies based on the human ESC line used. We aimed to develop a novel protocol to increase the formation of motoneurons from human ESCs. In this study, we tested a nuclear histone deacetylase protein, Sirt1, to promote neural precursor cell (NPC) development during differentiation of human ESCs into motoneurons. A specific inhibitor of Sirt1, nicotinamide, dramatically increased motoneuron formation. We found that about 60% of the cells from the total NPCs expressed HB9 and βIII-tubulin, commonly used motoneuronal markers found in neurons derived from ESCs following nicotinamide treatment. Motoneurons derived from ESC expressed choline acetyltransferase (ChAT), a positive marker of mature motoneuron. Moreover, we also examined the transcript levels of Mash1, Ngn2, and HB9 mRNA in the differentiated NPCs treated with the Sirt1 activator resveratrol (50 μM) or inhibitor nicotinamide (100 μM). The levels of Mash1, Ngn2, and HB9 mRNA were significantly increased after nicotinamide treatment compared with control groups, which used the traditional protocol. These results suggested that increasing Mash1 and Ngn2 levels by inhibiting Sirt1 could elevate HB9 expression, which promotes motoneuron differentiation. This study provides an alternative method for the production of transplantable motoneurons, a key requirement in the development of hESC-based cell therapy in motoneuron disease.

Structural and Kinetic Isotope Effect Studies of Nicotinamidase (Pnc1) from Saccharomyces cerevisiae

Energy Technology Data Exchange (ETDEWEB)

Smith, Brian C.; Anderson, Mark A.; Hoadley, Kelly A.; Keck, James L.; Cleland, W. Wallace; Denu, John M. (UW)

2012-05-08

Nicotinamidases catalyze the hydrolysis of nicotinamide to nicotinic acid and ammonia. Nicotinamidases are absent in mammals but function in NAD{sup +} salvage in many bacteria, yeast, plants, protozoa, and metazoans. We have performed structural and kinetic investigations of the nicotinamidase from Saccharomyces cerevisiae (Pnc1). Steady-state product inhibitor analysis revealed an irreversible reaction in which ammonia is the first product released, followed by nicotinic acid. A series of nicotinamide analogues acting as inhibitors or substrates were examined, revealing that the nicotinamide carbonyl oxygen and ring nitrogen are critical for binding and reactivity. X-ray structural analysis revealed a covalent adduct between nicotinaldehyde and Cys167 of Pnc1 and coordination of the nicotinamide ring nitrogen to the active-site zinc ion. Using this structure as a guide, the function of several residues was probed via mutagenesis and primary {sup 15}N and {sup 13}C kinetic isotope effects (KIEs) on V/K for amide bond hydrolysis. The KIE values of almost all variants were increased, indicating that C-N bond cleavage is at least partially rate limiting; however, a decreased KIE for D51N was indicative of a stronger commitment to catalysis. In addition, KIE values using slower alternate substrates indicated that C-N bond cleavage is at least partially rate limiting with nicotinamide to highly rate limiting with thionicotinamide. A detailed mechanism involving nucleophilic attack of Cys167, followed by elimination of ammonia and then hydrolysis to liberate nicotinic acid, is discussed. These results will aid in the design of mechanism-based inhibitors to target pathogens that rely on nicotinamidase activity.

Significance of manipulating tumour hypoxia and radiation dose rate in terms of local tumour response and lung metastatic potential, referring to the response of quiescent cell populations

Science.gov (United States)

Masunaga, S; Matsumoto, Y; Kashino, G; Hirayama, R; Liu, Y; Tanaka, H; Sakurai, Y; Suzuki, M; Kinashi, Y; Maruhashi, A; Ono, K

2010-01-01

The purpose of this study was to evaluate the influence of manipulating intratumour oxygenation status and radiation dose rate on local tumour response and lung metastases following radiotherapy, referring to the response of quiescent cell populations within irradiated tumours. B16-BL6 melanoma tumour-bearing C57BL/6 mice were continuously given 5-bromo-2′-deoxyuridine (BrdU) to label all proliferating (P) cells. They received γ-ray irradiation at high dose rate (HDR) or reduced dose rate (RDR) following treatment with the acute hypoxia-releasing agent nicotinamide or local hyperthermia at mild temperatures (MTH). Immediately after the irradiation, cells from some tumours were isolated and incubated with a cytokinesis blocker. The responses of the quiescent (Q) and total (proliferating + Q) cell populations were assessed based on the frequency of micronuclei using immunofluorescence staining for BrdU. In other tumour-bearing mice, 17 days after irradiation, macroscopic lung metastases were enumerated. Following HDR irradiation, nicotinamide and MTH enhanced the sensitivity of the total and Q-cell populations, respectively. The decrease in sensitivity at RDR irradiation compared with HDR irradiation was slightly inhibited by MTH, especially in Q cells. Without γ-ray irradiation, nicotinamide treatment tended to reduce the number of lung metastases. With γ-rays, in combination with nicotinamide or MTH, especially the former, HDR irradiation decreased the number of metastases more remarkably than RDR irradiation. Manipulating both tumour hypoxia and irradiation dose rate have the potential to influence lung metastasis. The combination with the acute hypoxia-releasing agent nicotinamide may be more promising in HDR than RDR irradiation in terms of reducing the number of lung metastases. PMID:20739345

Increased life span due to calorie restriction in respiratory-deficient yeast.

Directory of Open Access Journals (Sweden)

Matt Kaeberlein

2005-11-01

Full Text Available A model for replicative life span extension by calorie restriction (CR in yeast has been proposed whereby reduced glucose in the growth medium leads to activation of the NAD+-dependent histone deacetylase Sir2. One mechanism proposed for this putative activation of Sir2 is that CR enhances the rate of respiration, in turn leading to altered levels of NAD+ or NADH, and ultimately resulting in enhanced Sir2 activity. An alternative mechanism has been proposed in which CR decreases levels of the Sir2 inhibitor nicotinamide through increased expression of the gene coding for nicotinamidase, PNC1. We have previously reported that life span extension by CR is not dependent on Sir2 in the long-lived BY4742 strain background. Here we have determined the requirement for respiration and the effect of nicotinamide levels on life span extension by CR. We find that CR confers robust life span extension in respiratory-deficient cells independent of strain background, and moreover, suppresses the premature mortality associated with loss of mitochondrial DNA in the short-lived PSY316 strain. Addition of nicotinamide to the medium dramatically shortens the life span of wild type cells, due to inhibition of Sir2. However, even in cells lacking both Sir2 and the replication fork block protein Fob1, nicotinamide partially prevents life span extension by CR. These findings (1 demonstrate that respiration is not required for the longevity benefits of CR in yeast, (2 show that nicotinamide inhibits life span extension by CR through a Sir2-independent mechanism, and (3 suggest that CR acts through a conserved, Sir2-independent mechanism in both PSY316 and BY4742.

Perturbations of NAD+ salvage systems impact mitochondrial function and energy homeostasis in mouse myoblasts and intact skeletal muscle

DEFF Research Database (Denmark)

Andersen, Marianne Agerholm; Dall, Morten; Jensen, Benjamin Anderschou Holbech

2018-01-01

Nicotinamide adenine dinucleotide (NAD+) can be synthesized by nicotinamide phosphoribosyltransferase (NAMPT). We aimed to determine the role of NAMPT for maintaining NAD+ levels, mitochondrial function, and metabolic homeostasis in skeletal muscle cells. We generated stable Nampt knockdown (sh......Nampt KD) C2C12 cells using a shRNA lentiviral approach. Moreover, we applied gene electrotransfer to express cre recombinase in tibialis anterior muscle of floxed Nampt mice. In shNampt KD C2C12 myoblasts, Nampt and NAD+ levels were reduced by 70% and 50%, respectively, and maximal respiratory capacity...... was reduced by 25%. Moreover, anaerobic glycolytic flux increased by 55% and 2-deoxyglucose uptake increased by 25% in shNampt KD cells. Treatment with the NAD+ precursor nicotinamide riboside restored NAD+ levels in shNampt cells and increased maximal respiratory capacity by 18% and 32% in control and sh...

Anticancer agent CHS-828 inhibits cellular synthesis of NAD

DEFF Research Database (Denmark)

Olesen, U.H.; Christensen, M.K.; Bjorkling, F.

2008-01-01

Malignant cells display increased demands for energy production and DNA repair. Nicotinamide adenine dinucleotide (NAD) is required for both processes and is also continuously degraded by cellular enzymes. Nicotinamide phosphoribosyltransferase (Nampt) is a crucial factor in the resynthesis of NAD......, and thus in cancer cell survival. Here, we establish the cytotoxic mechanism of action of the small molecule inhibitor CHS-828 to result from impaired synthesis of NAD. Initially, we detected cross-resistance in cells between CHS-828 and a known inhibitor of Nampt, FK866, a compound of a structurally...... different class. We then showed that nicotinamide protects against CHS-828-mediated cytotoxicity. Finally, we observed that treatment with CHS-828 depletes cellular NAD levels in sensitive cancer cells. In conclusion, these results strongly suggest that, like FK866, CHS-828 kills cancer cells by depleting...

Visfatin expression analysis in association with recruitment and activation of human and rodent brown and brite adipocytes

OpenAIRE

Pisani, Didier F.; Dumortier, Olivier; Beranger, Guillaume E.; Casamento, Virginie; Ghandour, Rayane A.; Giroud, Maude; Gautier, Nadine; Balaguer, Thierry; Chambard, Jean-Claude; Virtanen, Kirsi A.; Nuutila, Pirjo; Niemi, Tarja; Taittonen, Markku; Van Obberghen, Emmanuel; Hinault, Charlotte

2015-01-01

Human brown adipocytes are able to burn fat and glucose and are now considered as a potential strategy to treat obesity, type 2 diabetes and metabolic disorders. Besides their thermogenic function, brown adipocytes are able to secrete adipokines. One of these is visfatin, a nicotinamide phosphoribosyltransferase involved in nicotinamide dinucleotide synthesis, which is known to participate in the synthesis of insulin by pancreatic β cells. In a therapeutic context, it is of interest to establ...

Leishmania infantum nicotinamidase is required for late-stage development in its natural sand fly vector, Phlebotomus perniciosus

OpenAIRE

Gazanion, Elodie; Seblova, V.; Votypka, J.; Vergnes, Baptiste; Garcia, Deborah; Volf, P.; Sereno, Denis

2012-01-01

Leishmania infantum nicotinamidase, encoded by the Lipnc1 gene, converts nicotinamide into nicotinic acid to ensure Nicotinamide-Adenine-Dinucleotide (NAD(+)) biosynthesis. We were curious to explore the role of this enzyme during L infantum development in its natural sand fly vector, Phlebotomus perniciosus (Diptera, Phlebotominae), using null mutants with a deleted Lipnc1 gene. The null mutants developed as well as the wild type L infantum at the early time points post their ingestion withi...

Evaluation of n+Mn-55 cross section data up to 150 MeV neutron energy

International Nuclear Information System (INIS)

Pereslavtsev, P.; Fischer, U.

2008-01-01

A new evaluation was performed for the reaction system n + 55 Mn in the neutron energy range from 0.001 to 150 MeV. The evaluation is based on the use of the ECIS96 and GNASH codes. A good description of available experimental data was achieved. A very limited set of existing evaluated data from the available international nuclear data libraries was used for the evaluation. The final general purpose data file was prepared in standard ENDF-6 format and was verified with standard format checking utilities. The data file will undergo benchmark testing and will be finally integrated into the JEFF-3.2 data library. (authors)

ORF Alignment: NC_004741 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available A64852.1| OrfUU ... pdb|1K4M|C Chain C, Crystal Structure Of E.Coli ... Nicotinic Acid Mononuc...B, Crystal ... Structure Of E.Coli Nicotinic Acid Mononucleotide ... Adenylyltransferase Compl...exed To Deamido-Nad pdb|1K4M|A ... Chain A, Crystal Structure Of E.Coli Nicotinic Acid ... Mon

ORF Alignment: NC_000913 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available A64852.1| OrfUU ... pdb|1K4M|C Chain C, Crystal Structure Of E.Coli ... Nicotinic Acid Mononuc...B, Crystal ... Structure Of E.Coli Nicotinic Acid Mononucleotide ... Adenylyltransferase Compl...exed To Deamido-Nad pdb|1K4M|A ... Chain A, Crystal Structure Of E.Coli Nicotinic Acid ... Mon

ORF Alignment: NC_004337 [GENIUS II[Archive

Lifescience Database Archive (English)

Full Text Available A64852.1| OrfUU ... pdb|1K4M|C Chain C, Crystal Structure Of E.Coli ... Nicotinic Acid Mononuc...B, Crystal ... Structure Of E.Coli Nicotinic Acid Mononucleotide ... Adenylyltransferase Compl...exed To Deamido-Nad pdb|1K4M|A ... Chain A, Crystal Structure Of E.Coli Nicotinic Acid ... Mon

NAD+-Dependent Deacetylase Hst1p Controls Biosynthesis and Cellular NAD+ Levels in Saccharomyces cerevisiae

OpenAIRE

Bedalov, Antonio; Hirao, Maki; Posakony, Jeffrey; Nelson, Melisa; Simon, Julian A.

2003-01-01

Nicotine adenine dinucleotide (NAD+) performs key roles in electron transport reactions, as a substrate for poly(ADP-ribose) polymerase and NAD+-dependent protein deacetylases. In the latter two processes, NAD+ is consumed and converted to ADP-ribose and nicotinamide. NAD+ levels can be maintained by regeneration of NAD+ from nicotinamide via a salvage pathway or by de novo synthesis of NAD+ from tryptophan. Both pathways are conserved from yeast to humans. We describe a critical role of the ...

Nicotine-selective radiation-induced poly(acrylamide/maleic acid) hydrogels

International Nuclear Information System (INIS)

Saraydin, D.; Karadag, E.; Caldiran, Y.; Gueven, O.

2001-01-01

Nicotine-selective poly(acrylamide/maleic acid) (AAm/MA) hydrogels prepared by γ-irradiation were used in experiments on swelling, diffusion, and interactions of the pharmaceuticals nicotine, nicotinic acid, nicotinamide, and nikethamide. For AAm/MA hydrogel containing 60 mg maleic acid and irradiated at 5.2 kGy, the studies indicated that swelling increased in the following order; nicotine>nicotinamide>nikethamide>nicotinic acid>water. Diffusions of water and the pharmaceuticals within the hydrogels were found to be non-Fickian in character. AAm/MA hydrogel sorbed only nicotine and did not sorb nicotinamide, nikethamide and nicotinic acid in the binding experiments. S-type adsorption in Giles's classification system was observed. Some binding and thermodynamic parameters for AAm/MA hydrogel-nicotine system were calculated using the Scatchard method. The values of adsorption heat and free energy of this system were found to be negative whereas adsorption entropy was found to be positive. (author)

Effects of Trigonelline, an Alkaloid Present in Coffee, on Diabetes-Induced Disorders in the Rat Skeletal System.

Science.gov (United States)

Folwarczna, Joanna; Janas, Aleksandra; Pytlik, Maria; Cegieła, Urszula; Śliwiński, Leszek; Krivošíková, Zora; Štefíková, Kornélia; Gajdoš, Martin

2016-03-02

Diabetes increases bone fracture risk. Trigonelline, an alkaloid with potential antidiabetic activity, is present in considerable amounts in coffee. The aim of the study was to investigate the effects of trigonelline on experimental diabetes-induced disorders in the rat skeletal system. Effects of trigonelline (50 mg/kg p.o. daily for four weeks) were investigated in three-month-old female Wistar rats, which, two weeks before the start of trigonelline administration, received streptozotocin (60 mg/kg i.p.) or streptozotocin after nicotinamide (230 mg/kg i.p.). Serum bone turnover markers, bone mineralization, and mechanical properties were studied. Streptozotocin induced diabetes, with significant worsening of bone mineralization and bone mechanical properties. Streptozotocin after nicotinamide induced slight glycemia increases in first days of experiment only, however worsening of cancellous bone mechanical properties and decreased vertebral bone mineral density (BMD) were demonstrated. Trigonelline decreased bone mineralization and tended to worsen bone mechanical properties in streptozotocin-induced diabetic rats. In nicotinamide/streptozotocin-treated rats, trigonelline significantly increased BMD and tended to improve cancellous bone strength. Trigonelline differentially affected the skeletal system of rats with streptozotocin-induced metabolic disorders, intensifying the osteoporotic changes in streptozotocin-treated rats and favorably affecting bones in the non-hyperglycemic (nicotinamide/streptozotocin-treated) rats. The results indicate that, in certain conditions, trigonelline may damage bone.

The evolutionary portrait of metazoan NAD salvage.

Science.gov (United States)

Carneiro, João; Duarte-Pereira, Sara; Azevedo, Luísa; Castro, L Filipe C; Aguiar, Paulo; Moreira, Irina S; Amorim, António; Silva, Raquel M

2013-01-01

Nicotinamide Adenine Dinucleotide (NAD) levels are essential for cellular homeostasis and survival. Main sources of intracellular NAD are the salvage pathways from nicotinamide, where Nicotinamide phosphoribosyltransferases (NAMPTs) and Nicotinamidases (PNCs) have a key role. NAMPTs and PNCs are important in aging, infection and disease conditions such as diabetes and cancer. These enzymes have been considered redundant since either one or the other exists in each individual genome. The co-occurrence of NAMPT and PNC was only recently detected in invertebrates though no structural or functional characterization exists for them. Here, using expression and evolutionary analysis combined with homology modeling and protein-ligand docking, we show that both genes are expressed simultaneously in key species of major invertebrate branches and emphasize sequence and structural conservation patterns in metazoan NAMPT and PNC homologues. The results anticipate that NAMPTs and PNCs are simultaneously active, raising the possibility that NAD salvage pathways are not redundant as both are maintained to fulfill the requirement for NAD production in some species.

Aplicação de métodos de calibração multivariada para a determinação simultânea de riboflavina (VB2, tiamina (VB1, piridoxina (VB6 e nicotinamida (VPP UV spectrophotrometry and chemometrics methods for simultaneous determinations of riboflavin (VB2, thiamine (VB1, pyridoxine (VB6 and nicotinamide (VPP

Directory of Open Access Journals (Sweden)

Rosângela C. Barthus

2007-01-01

Full Text Available In this work, the artificial neural networks (ANN and partial least squares (PLS regression were applied to UV spectral data for quantitative determination of thiamin hydrochloride (VB1, riboflavin phosphate (VB2, pyridoxine hydrochloride (VB6 and nicotinamide (VPP in pharmaceutical samples. For calibration purposes, commercial samples in 0.2 mol L-1 acetate buffer (pH 4.0 were employed as standards. The concentration ranges used in the calibration step were: 0.1 - 7.5 mg L-1 for VB1, 0.1 - 3.0 mg L-1 for VB2, 0.1 - 3.0 mg L-1 for VB6 and 0.4 - 30.0 mg L-1 for VPP. From the results it is possible to verify that both methods can be successfully applied for these determinations. The similar error values were obtained by using neural network or PLS methods. The proposed methodology is simple, rapid and can be easily used in quality control laboratories.

SirT1 confers hypoxia-induced radioresistance via the modulation of c-Myc stabilization on hepatoma cells

International Nuclear Information System (INIS)

Xie Yuexia; Zhang Jianghong; Shao Chunlin; Xu Yanwu

2012-01-01

Intratumoral hypoxia is an important contributory factor to tumor cell resistance to radiotherapy. SirT1, a nicotinamide adenine dinucleotide (NAD + )-dependent histone/protein deacetylase, has been linked to the decrease of radiation-induced DNA damage and seems to be critical for cancer therapy. The purpose of this study was to investigate the role of SirT1 in hypoxia-induced radiation response on hepatoma cells. It was found that the administration with resveratrol, a putative SirT1 activator, enhanced the resistance of HepG2 cells against radiation-induced DNA damage of MN formation under hypoxia condition; while nicotinamide, a well-known SirT1 inhibitor, sensitized this radiation damage. Nevertheless, pretreatment of cells with 10058-F4, a specific inhibitor of c-Myc, almost eliminated the nicotinamide-induced radiosensitive effect. Further studies revealed that resveratrol inhibited c-Myc protein accumulation via up-regulation of SirT1 expression and deacetylase activity, and this loss of c-Myc protein was abolished by inhibiting its degradation in the presence of MG132, a potent inhibitor of proteasome. In contrast, nicotinamide attenuated c-Myc protein degradation induced by radiation under hypoxia through inhibition of SirT1 deacetylase activity. Our findings suggest that SirT1 could serve as a novel potent target of radiation-induced DNA damage and thus as a potential strategy to advance the efficiency of radiation therapy in hepatoma entities. (author)

Protonation mechanism and location of rate-determining steps for the Ascaris suum nicotinamide adenine dinucleotide-malic enzyme reaction from isotope effects and pH studies

International Nuclear Information System (INIS)

Kiick, D.M.; Harris, B.G.; Cook, P.F.

1986-01-01

The pH dependence of the kinetic parameters and the primary deuterium isotope effects with nicotinamide adenine dinucleotide (NAD) and also thionicotinamide adenine dinucleotide (thio-NAD) as the nucleotide substrates were determined in order to obtain information about the chemical mechanism and location of rate-determining steps for the Ascaris suum NAD-malic enzyme reaction. The maximum velocity with thio-NAD as the nucleotide is pH-independent from pH 4.2 to 9.6, while with NAD, V decreases below a pK of 4.8. V/K for both nucleotides decreases below a pK of 5.6 and above a pK of 8.9. Both the tartronate pKi and V/Kmalate decrease below a pK of 4.8 and above a pK of 8.9. Oxalate is competitive vs. malate above pH 7 and noncompetitive below pH 7 with NAD as the nucleotide. The oxalate Kis increases from a constant value above a pK of 4.9 to another constant value above a pK of 6.7. The oxalate Kii also increases above a pK of 4.9, and this inhibition is enhanced by NADH. In the presence of thio-NAD the inhibition by oxalate is competitive vs. malate below pH 7. For thio-NAD, both DV and D(V/K) are pH-independent and equal to 1.7. With NAD as the nucleotide, DV decreases to 1.0 below a pK of 4.9, while D(V/KNAD) and D(V/Kmalate) are pH-independent. Above pH 7 the isotope effects on V and the V/K values for NAD and malate are equal to 1.45, the pH-independent value of DV above pH 7. Results indicate that substrates bind to only the correctly protonated form of the enzyme. Two enzyme groups are necessary for binding of substrates and catalysis. Both NAD and malate are released from the Michaelis complex at equal rates which are equal to the rate of NADH release from E-NADH above pH 7. Below pH 7 NADH release becomes more rate-determining as the pH decreases until at pH 4.0 it completely limits the overall rate of the reaction

Tirapazamine vs carbogen and nicotinamide with fractionated irradiation. What is the optimum time of giving tirapazamine during the course of irradiation?

International Nuclear Information System (INIS)

Elsaid, A.A.; Menke, D.; Dorie, M.J.; Brown, J.M.

1996-01-01

Purpose: 1) To compare in a fractionated regimen, with clinically relevant radiation doses, using human tumor xenografts, two radiation response modifiers that function by different mechanisms: A) Tirapazamine (TPZ), a bioreductive drug of the benzotriazine-di-N-oxide class which shows a highly selective cytotoxicity for hypoxic cells. B) Nicotinamide (NAM), an amide of vitamin B 3 , with Carbogen breathing (CBG), a combination that has been shown to reduce both acute (perfusion-limited) hypoxia and chronic (diffusion-limited) hypoxia. 2) To determine the optimum time of giving TPZ during the course of irradiation (XRT). Materials and Methods: Cell survival assays were used to examine the response of two different human tumor xenografts: FaDu, a carcinoma of the head and neck, and HT29, a colon carcinoma, in SCID mice. Growth delay studies were performed with the FaDu tumor to compare the following treatments: TPZ with XRT, NAM + CBG with XRT, and TPZ + NAM + CBG with XRT. Clinical phase I studies of TPZ have been completed and suggest that a fractionated course of 3 fractions/week of TPZ is tolerable at an effective cytotoxic dose. However, if hypoxic cells are present in the tumor on the days that TPZ is not given (i.e. rehypoxiation has occurred) then this will reduce the effectiveness of the drug-radiation combination. To investigate this we have given CBG and NAM on the days TPZ is not given with fractionated irradiation. The fractionated irradiation schedule consisted of 2.0 or 2.5 Gy once or twice daily for one or two weeks with and without drug pre treatment. TPZ was given i.p. at 0.08 mmol/kg 30 min before irradiation for the whole course, or for 3 fractions per week alone, or with 2 fractions per week of NAM and CBG. NAM was given i.p. at 1000 mg/kg, 1 hr prior to irradiation, with CBG exposure 5 min. prior to and during the irradiation. Another growth delay study is being performed to investigate which schedule produces the most enhancement: TPZ during

Structure and Mechanism of a Eukaryotic FMN Adenylyltransferase

OpenAIRE

Huerta, Carlos; Borek, Dominika; Machius, Mischa; Grishin, Nick V.; Zhang, Hong

2009-01-01

Flavin mononucleotide adenylyltransferase (FMNAT) catalyzes the formation of the essential flavocoenzyme FAD and plays an important role in flavocoenzyme homeostasis regulation. By sequence comparison, bacterial and eukaryotic FMNAT enzymes belong to two different protein superfamilies and apparently utilize different set of active site residues to accomplish the same chemistry. Here we report the first structural characterization of a eukaryotic FMNAT from a pathogenic yeast Candida glabrata...

The evolutionary portrait of metazoan NAD salvage.

Directory of Open Access Journals (Sweden)

João Carneiro

Full Text Available Nicotinamide Adenine Dinucleotide (NAD levels are essential for cellular homeostasis and survival. Main sources of intracellular NAD are the salvage pathways from nicotinamide, where Nicotinamide phosphoribosyltransferases (NAMPTs and Nicotinamidases (PNCs have a key role. NAMPTs and PNCs are important in aging, infection and disease conditions such as diabetes and cancer. These enzymes have been considered redundant since either one or the other exists in each individual genome. The co-occurrence of NAMPT and PNC was only recently detected in invertebrates though no structural or functional characterization exists for them. Here, using expression and evolutionary analysis combined with homology modeling and protein-ligand docking, we show that both genes are expressed simultaneously in key species of major invertebrate branches and emphasize sequence and structural conservation patterns in metazoan NAMPT and PNC homologues. The results anticipate that NAMPTs and PNCs are simultaneously active, raising the possibility that NAD salvage pathways are not redundant as both are maintained to fulfill the requirement for NAD production in some species.

Assimilation of NAD(+) precursors in Candida glabrata.

Science.gov (United States)

Ma, Biao; Pan, Shih-Jung; Zupancic, Margaret L; Cormack, Brendan P

2007-10-01

The yeast pathogen Candida glabrata is a nicotinamide adenine dinucleotide (NAD(+)) auxotroph and its growth depends on the environmental supply of vitamin precursors of NAD(+). C. glabrata salvage pathways defined in this article allow NAD(+) to be synthesized from three compounds - nicotinic acid (NA), nicotinamide (NAM) and nicotinamide riboside (NR). NA is salvaged through a functional Preiss-Handler pathway. NAM is first converted to NA by nicotinamidase and then salvaged by the Preiss-Handler pathway. Salvage of NR in C. glabrata occurs via two routes. The first, in which NR is phosphorylated by the NR kinase Nrk1, is independent of the Preiss-Handler pathway. The second is a novel pathway in which NR is degraded by the nucleosidases Pnp1 and Urh1, with a minor role for Meu1, and ultimately converted to NAD(+) via the nicotinamidase Pnc1 and the Preiss-Handler pathway. Using C. glabrata mutants whose growth depends exclusively on the external NA or NR supply, we also show that C. glabrata utilizes NR and to a lesser extent NA as NAD(+) sources during disseminated infection.

New chloroplast microsatellite markers suitable for assessing genetic diversity of Lolium perenne and other related grass species.

Science.gov (United States)

Diekmann, Kerstin; Hodkinson, Trevor R; Barth, Susanne

2012-11-01

Lolium perenne (perennial ryegrass) is the most important forage grass species of temperate regions. We have previously released the chloroplast genome sequence of L. perenne 'Cashel'. Here nine chloroplast microsatellite markers are published, which were designed based on knowledge about genetically variable regions within the L. perenne chloroplast genome. These markers were successfully used for characterizing the genetic diversity in Lolium and different grass species. Chloroplast genomes of 14 Poaceae taxa were screened for mononucleotide microsatellite repeat regions and primers designed for their amplification from nine loci. The potential of these markers to assess genetic diversity was evaluated on a set of 16 Irish and 15 European L. perenne ecotypes, nine L. perenne cultivars, other Lolium taxa and other grass species. All analysed Poaceae chloroplast genomes contained more than 200 mononucleotide repeats (chloroplast simple sequence repeats, cpSSRs) of at least 7 bp in length, concentrated mainly in the large single copy region of the genome. Nucleotide composition varied considerably among subfamilies (with Pooideae biased towards poly A repeats). The nine new markers distinguish L. perenne from all non-Lolium taxa. TeaCpSSR28 was able to distinguish between all Lolium species and Lolium multiflorum due to an elongation of an A(8) mononucleotide repeat in L. multiflorum. TeaCpSSR31 detected a considerable degree of microsatellite length variation and single nucleotide polymorphism. TeaCpSSR27 revealed variation within some L. perenne accessions due to a 44-bp indel and was hence readily detected by simple agarose gel electrophoresis. Smaller insertion/deletion events or single nucleotide polymorphisms detected by these new markers could be visualized by polyacrylamide gel electrophoresis or DNA sequencing, respectively. The new markers are a valuable tool for plant breeding companies, seed testing agencies and the wider scientific community due to

NAD+ repletion improves muscle function in muscular dystrophy and counters global PARylation.

Science.gov (United States)

Ryu, Dongryeol; Zhang, Hongbo; Ropelle, Eduardo R; Sorrentino, Vincenzo; Mázala, Davi A G; Mouchiroud, Laurent; Marshall, Philip L; Campbell, Matthew D; Ali, Amir Safi; Knowels, Gary M; Bellemin, Stéphanie; Iyer, Shama R; Wang, Xu; Gariani, Karim; Sauve, Anthony A; Cantó, Carles; Conley, Kevin E; Walter, Ludivine; Lovering, Richard M; Chin, Eva R; Jasmin, Bernard J; Marcinek, David J; Menzies, Keir J; Auwerx, Johan

2016-10-19

Neuromuscular diseases are often caused by inherited mutations that lead to progressive skeletal muscle weakness and degeneration. In diverse populations of normal healthy mice, we observed correlations between the abundance of mRNA transcripts related to mitochondrial biogenesis, the dystrophin-sarcoglycan complex, and nicotinamide adenine dinucleotide (NAD + ) synthesis, consistent with a potential role for the essential cofactor NAD + in protecting muscle from metabolic and structural degeneration. Furthermore, the skeletal muscle transcriptomes of patients with Duchene's muscular dystrophy (DMD) and other muscle diseases were enriched for various poly[adenosine 5'-diphosphate (ADP)-ribose] polymerases (PARPs) and for nicotinamide N-methyltransferase (NNMT), enzymes that are major consumers of NAD + and are involved in pleiotropic events, including inflammation. In the mdx mouse model of DMD, we observed significant reductions in muscle NAD + levels, concurrent increases in PARP activity, and reduced expression of nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme for NAD + biosynthesis. Replenishing NAD + stores with dietary nicotinamide riboside supplementation improved muscle function and heart pathology in mdx and mdx/Utr -/- mice and reversed pathology in Caenorhabditis elegans models of DMD. The effects of NAD + repletion in mdx mice relied on the improvement in mitochondrial function and structural protein expression (α-dystrobrevin and δ-sarcoglycan) and on the reductions in general poly(ADP)-ribosylation, inflammation, and fibrosis. In combination, these studies suggest that the replenishment of NAD + may benefit patients with muscular dystrophies or other neuromuscular degenerative conditions characterized by the PARP/NNMT gene expression signatures. Copyright © 2016, American Association for the Advancement of Science.

Feasibility of electrospray deposition for rapid screening of the cocrystal formation and single step, continuous production of pharmaceutical nanococrystals.

Science.gov (United States)

Emami, Shahram; Siahi-Shadbad, Mohammadreza; Barzegar-Jalali, Mohammad; Adibkia, Khosro

2018-06-01

This study employed electrospray deposition (ESD) for simultaneous synthesis and particle engineering of cocrystals. Exploring new methods for the efficient production of cocrystals with desired particle properties is an essential demand. The possibility of cocrystal formation by ESD was examined for indomethacin-saccharin, indomethacin-nicotinamide, naproxen-nicotinamide, and naproxen-iso-nicotinamide cocrystals. Solutions of the drug and coformer at stoichiometric ratios were sprayed to a high electric field which caused rapid evaporation of the solvent and the formation of fine particles. The phase purity, size, and morphology of products were compared with reference cocrystals. Experiments were performed to evaluate the effects of stoichiometric ratio, concentration and solvent type on the cocrystal formation. Physical stability and dissolution properties of the electrosprayed cocrystals were also compared with reference cocrystals. ESD was found to be an efficient and rapid method to produce cocrystals for all studied systems other than indomethacin-nicotinamide. Pure cocrystals only formed at a specific drug:coformer ratio. The solvent type has a weak effect on the cocrystal formation and morphology. Electrosprayed cocrystals exhibited nano to micrometer sizes with distinct morphologies with comparable physical stability with reference cocrystals. Nanococrystals of indomethacin-saccharin with a mean size of 219 nm displayed a threefold higher dissolution rate than solvent evaporated cocrystal. ESD successfully was utilized to produce pure cocrystals of poorly soluble drugs with different morphologies and sizes ranging from nano to micrometer sizes in one step. This study highlighted the usefulness of ESD for simultaneous preparation and particle engineering of pharmaceutical cocrystals.

The influence of inhibitors of poly (ADP-ribose) polymerase on X-ray induced potentially lethal damage repair

International Nuclear Information System (INIS)

Brown, D.M.; Evans, J.W.; Brown, J.M.

1984-01-01

Inhibition of repair of X-ray-induced potentially lethal damage (PLD) could enhance the curability of radioresistant tumours. We have studied the effect of inhibitors of the enzyme poly (ADP-ribose) polymerase on X-ray PLD repair. Four classes of inhibitors are known: aromatic amides (e.g., 3-aminobenzamide), thymidine, nicotinamides and methyl xanthines (e.g., caffeine). Plateau-phase Chinese hamster ovary (HA-1) cultures were exposed to 10 mM concentrations of thymidine, nicotinamide, 3-aminobenzamide (3-ABA) and caffeine prior to irradiation to 12 Gy in air, and then incubated with drug at 37 0 C for varying times (0-6 h) prior to subculture. Irradiated cells without drug exhibited a 5-6 fold increase in survival over the 6 h period compared to cultures plated immediately after irradiation. Although none of the compounds proved cytotoxic to unirradiated controls over the 6.5 h exposure, all of the compounds except thymidine reduced the capacity of the cells to repair PLD. The order of the inhibitory effect was caffeine > 3-ABA > nicotinamide, and the inhibition was concentration dependent for nicotinamide and 3-ABA. We also studied the effect of 3-ABA on the radiation response of exponentially growing cells. 5 mM 3-ABA for 2h post-irradiation resulted in a dose-multiplicative sensitization reducing the D 0 from 0.88 Gy to 0.69 Gy, indicating an involvement of poly (ADP-ribose) polymerase in the radiosensitivity of exponentially growing as well as plateau-phase cells. (author)

Reducing intratumour acute hypoxia through bevacizumab treatment, referring to the response of quiescent tumour cells and metastatic potential

Science.gov (United States)

Masunaga, S; Liu, Y; Tanaka, H; Sakurai, Y; Suzuki, M; Kondo, N; Maruhashi, A; Ono, K

2011-01-01

Objectives The aim was to evaluate the influence of bevacizumab on intratumour oxygenation status and lung metastasis following radiotherapy, with specific reference to the response of quiescent (Q) cell populations within irradiated tumours. Methods B16-BL6 melanoma tumour-bearing C57BL/6 mice were continuously given 5-bromo-2-deoxyuridine (BrdU) to label all proliferating (P) cells. They received γ-ray irradiation following treatment with the acute hypoxia-releasing agent nicotinamide or local mild temperature hyperthermia (MTH) with or without the administration of bevacizumab under aerobic conditions or totally hypoxic conditions, achieved by clamping the proximal end of the tumours. Immediately after the irradiation, cells from some tumours were isolated and incubated with a cytokinesis blocker. The responses of the Q and total (P + Q) cell populations were assessed based on the frequency of micronuclei using immunofluorescence staining for BrdU. In the other tumour-bearing mice, macroscopic lung metastases were enumerated 17 days after irradiation. Results 3 days after bevacizumab administration, acute hypoxia-rich total cell population in the tumour showed a remarkably enhanced radiosensitivity to γ-rays, and the hypoxic fraction (HF) was reduced, even after MTH treatment. However, the hypoxic fraction was not reduced after nicotinamide treatment. With or without γ-ray irradiation, bevacizumab administration showed some potential to reduce the number of lung metastases as well as nicotinamide treatment. Conclusion Bevacizumab has the potential to reduce perfusion-limited acute hypoxia and some potential to cause a decrease in the number of lung metastases as well as nicotinamide. PMID:21586505

Nicotinamides: Evaluation of thermochemical experimental properties

International Nuclear Information System (INIS)

Zhabina, Aleksandra A.; Nagrimanov, Ruslan N.; Emel’yanenko, Vladimir N.; Solomonov, Boris N.; Verevkin, Sergey P.

2016-01-01

Highlights: • Vapor pressures measured by transpiration method. • Enthalpies of solution measured using high-precision solution calorimetry. • Enthalpies of fusion measured by DSC. • Sublimation enthalpies derived from transpiration and solution calorimetry in agreement. • Experimental results evaluated and compared with G4 calculations. - Abstract: Vapor pressures of the isomeric 2-, 3-, and 4-pyridinecarboxamides were measured by using the transpiration method. The enthalpies of sublimation/vaporization of these compounds at 298.15 K were derived from vapor pressure temperature dependences. The enthalpies of solution of the isomeric pyridinecarboxamides were measured with the high-precision solution calorimetry. The enthalpies of sublimation of 3- and 4-pyridinecarboxamides were independently derived with help of the solution calorimetry based procedure. The enthalpies of fusion of the pyridinecarboxamides were measured by the DSC. Thermochemical data isomeric pyridinecarboxamides were collected, evaluated, and tested for internal consistency. The high-level G4 quantum-chemical method was used for mutual validation of the experimental and theoretical gas phase enthalpies of formation successfully.

Impact of Genetic Reduction of NMNAT2 on Chemotherapy-Induced Losses in Cell Viability In Vitro and Peripheral Neuropathy In Vivo.

Directory of Open Access Journals (Sweden)

Richard A Slivicki

Full Text Available Nicotinamide mononucleotide adenylyl transferases (NMNATs are essential neuronal maintenance factors postulated to preserve neuronal function and protect against axonal degeneration in various neurodegenerative disease states. We used in vitro and in vivo approaches to assess the impact of NMNAT2 reduction on cellular and physiological functions induced by treatment with a vinca alkaloid (vincristine and a taxane-based (paclitaxel chemotherapeutic agent. NMNAT2 null (NMNAT2-/- mutant mice die at birth and cannot be used to probe functions of NMNAT2 in adult animals. Nonetheless, primary cortical cultures derived from NMNAT2-/- embryos showed reduced cell viability in response to either vincristine or paclitaxel treatment whereas those derived from NMNAT2 heterozygous (NMNAT2+/- mice were preferentially sensitive to vincristine-induced degeneration. Adult NMNAT2+/- mice, which survive to adulthood, exhibited a 50% reduction of NMNAT2 protein levels in dorsal root ganglia relative to wildtype (WT mice with no change in levels of other NMNAT isoforms (NMNAT1 or NMNAT3, NMNAT enzyme activity (i.e. NAD/NADH levels or microtubule associated protein-2 (MAP2 or neurofilament protein levels. We therefore compared the impact of NMNAT2 knockdown on the development and maintenance of chemotherapy-induced peripheral neuropathy induced by vincristine and paclitaxel treatment using NMNAT2+/- and WT mice. NMNAT2+/- did not differ from WT mice in either the development or maintenance of either mechanical or cold allodynia induced by either vincristine or paclitaxel treatment. Intradermal injection of capsaicin, the pungent ingredient in hot chili peppers, produced equivalent hypersensitivity in NMNAT2+/- and WT mice receiving vehicle in lieu of paclitaxel. Capsaicin-evoked hypersensitivity was enhanced by prior paclitaxel treatment but did not differ in either NMNAT2+/- or WT mice. Thus, capsaicin failed to unmask differences in nociceptive behaviors in either

Knockdown of NADPH-cytochrome P450 reductase results in reduced resistance to buprofezin in the small brown planthopper, Laodelphax striatellus (fallén).

Science.gov (United States)

Zhang, Yueliang; Wang, Yaming; Wang, Lihua; Yao, Jing; Guo, Huifang; Fang, Jichao

2016-02-01

NADPH-cytochrome P450 reductase (CPR) plays an important role in cytochrome P450 function, and CPR knockdown in several insects leads to increased susceptibility to insecticides. However, a putative CPR gene has not yet been fully characterized in the small brown planthopper Laodelphax striatellus, a notorious agricultural pest in rice that causes serious damage by transmitting rice stripe and rice black-streaked dwarf viruses. The objective of this study was to clone the cDNA and to knock down the expression of the gene that encodes L. striatellus CPR (LsCPR) to further determine whether P450s are involved in the resistance of L. striatellus to buprofezin. First, the full-length cDNA of LsCPR was cloned and found to contain an open reading frame (ORF) encoding a polypeptide of 679 amino acids with a calculated molecular mass and isoelectric point of 76.92kDa and 5.37, respectively. The deduced amino acid sequence shares high identity with the CPRs of other insects (98%, 97%, 75% and 68% for Sogatella furcifera, Nilaparvata lugens, Cimex lectularius and Anopheles gambiae, respectively) and possesses the characteristic features of classical CPRs, such as an N-terminal membrane anchor and conserved domains for flavin mononucleotide (FMN), flavin adenine dinucleotide (FAD) and nicotinamide adenine dinucleotide phosphate (NADPH) binding. Phylogenetic analysis revealed that LsCPR is located in a branch along with the CPRs of other hemipteran insects. LsCPR mRNA was detectable in all examined body parts and developmental stages of L. striatellus, as determined by real-time quantitative PCR (qPCR), and transcripts were most abundant in the adult abdomen and in first-instar nymphs and adults. Ingestion of 200μg/mL of LsCPR double-stranded RNA (dsLsCPR) by the planthopper for 5days significantly reduced the transcription level of LsCPR. Moreover, silencing of LsCPR caused increased susceptibility to buprofezin in a buprofezin-resistant (YN-BPF) strain but not in a

Preparation, characterization and in vitro evaluation of a new nucleotide analogue prodrug cyclodextrin inclusion complexes.

OpenAIRE

Diab , Roudayna; Jordheim , Lars P; Degobert , Ghania; Peyrottes , Suzanne; Périgaud , Christian; Dumontet , Charles; Fessi , Hatem

2009-01-01

International audience; Bis(tbutyl-S-acyl-2-thioethyl)-cytidine monophosophate is a new cytotoxic mononucleotide prodrug which have been developed to reverse the cellular resistance to nucleoside analogues. Unfortunately, its in vivo utilisation was hampered by its poor water solubility, raising the need of a molecular vector capable to mask its physicochemical characteristics although without affecting its cytotoxic activity. Hydroxypropyl-beta-cyclodextrin was used to prepare the prodrug in...

Human Postmeiotic Segregation 2 Exhibits Biased Repair at Tetranucleotide Microsatellite Sequences

OpenAIRE

Shah, Sandeep N.; Eckert, Kristin A.

2009-01-01

The mismatch repair (MMR) system plays a major role in removing DNA polymerization errors, and loss of this pathway results in hereditary cancers characterized by microsatellite instability. We investigated microsatellite stability during DNA replication within human postmeiotic segregation 2 (hPMS2)–deficient and proficient human lymphoblastoid cell lines. Using a shuttle vector assay, we measured mutation rates at reporter cassettes containing defined mononucleotide, dinucleotide, and tetra...

Anaerobic Aryl Reductive Dehalogenation of Halobenzoates by Cell Extracts of “Desulfomonile tiedjei”

OpenAIRE

DeWeerd, Kim A.; Suflita, Joseph M.

1990-01-01

We studied the transformation of halogenated benzoates by cell extracts of a dehalogenating anaerobe, “Desulfomonile tiedjei.” We found that cell extracts possessed aryl reductive dehalogenation activity. The activity was heat labile and dependent on the addition of reduced methyl viologen, but not on that of reduced NAD, NADP, flavin mononucleotide, flavin adenine dinucleotide, desulfoviridin, cytochrome c3, or benzyl viologen. Dehalogenation activity in extracts was stimulated by formate, C...

Genetic Transformation of an Obligate Anaerobe, P. gingivalis for FMN-Green Fluorescent Protein Expression in Studying Host-Microbe Interaction

OpenAIRE

Choi, Chul Hee; DeGuzman, Jefferson V.; Lamont, Richard J.; Yilmaz, Özlem

2011-01-01

The recent introduction of "oxygen-independent" flavin mononucleotide (FMN)-based fluorescent proteins (FbFPs) is of major interest to both eukaryotic and prokaryotic microbial biologists. Accordingly, we demonstrate for the first time that an obligate anaerobe, the successful opportunistic pathogen of the oral cavity, Porphyromonas gingivalis, can be genetically engineered for expression of the non-toxic green FbFP. The resulting transformants are functional for studying dynamic bacterial pr...

Nicotinic acid and nicotinamide on pear and apple flowers are not limiting factors for Erwinia amylovora growth when these chemicals are considered in relation to cultivar and flower age

Directory of Open Access Journals (Sweden)

Thomas PATERNOSTER

2011-05-01

Full Text Available Normal 0 14 false false false IT ZH-TW X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabella normale"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0cm; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Fire blight, caused by Erwinia amylovora, is a devastating disease of pear (Pyrus communis and apple (Malus × domestica in many areas of the world. The disease is often initiated by epiphytic populations that multiply on flowers and colonize the hypanthia. In vitro, E. amylovora requires nicotinic acid (NicAc and/or nicotinamide (NicNH2 as essential growth factors. The amount of NicAc on pear hypanthia was positively correlated with the altitude of the growing site and was inversely correlated with the sum of the maximum temperatures in the 30 days before flowering. The sum of the amounts of NicAc and NicNH2 on the hypanthia was about 6 to 23 times higher in pear, and about 1.2 to 3.5 times higher in apple, than the amounts of NicAc or NicNH2 necessary to support maximum E. amylovora growth  in vitro. No correlation was found between the amounts of NicAc and NicNH2 on the hypanthia of different pear and apple cultivars and at different growth stages and the growth of E. amylovora after experimental inoculation. In conclusion, NicAc and NicNH2 are essential for E. amylovora growth but the amounts of these chemicals on pear and apple flowers do not limit the establishment of the pathogen when competing bacteria

Compilation of 1990 Annual Reports of the Navy ELF Communications System Ecological Monitoring Program. Volume 3. Tabs G thru I.

Science.gov (United States)

1991-08-01

crowned Kinglet 12 11 1 3 5 0 0 9 3 4 i Reciulus calendula _Gnatcatcher 0 1 0 0 0 0 00 0Blue-grayGattce Polioptila caerulea Eastern Bluebird 0 0 0 0 1 0 6 0...and species determinations was done at 1250X magnification on a Zeiss microscope equipped with phase contrast illumination and an oil immersion 10OX...xx MMN M M N NŘ N NMN NM M N II~ ~ 0 a MM NM 333 30661 6961 x x x 39961 x x xK x x S996 x K K U I *c E I I. i~~ 0* oil ] o o I4 33 0) x LL 5 I. CoI

A Key Enzyme of the NAD+ Salvage Pathway in Thermus thermophilus: Characterization of Nicotinamidase and the Impact of Its Gene Deletion at High Temperatures.

Science.gov (United States)

Taniguchi, Hironori; Sungwallek, Sathidaphorn; Chotchuang, Phatcharin; Okano, Kenji; Honda, Kohsuke

2017-09-01

NAD (NAD + ) is a cofactor related to many cellular processes. This cofactor is known to be unstable, especially at high temperatures, where it chemically decomposes to nicotinamide and ADP-ribose. Bacteria, yeast, and higher organisms possess the salvage pathway for reconstructing NAD + from these decomposition products; however, the importance of the salvage pathway for survival is not well elucidated, except for in pathogens lacking the NAD + de novo synthesis pathway. Herein, we report the importance of the NAD + salvage pathway in the thermophilic bacterium Thermus thermophilus HB8 at high temperatures. We identified the gene encoding nicotinamidase (TTHA0328), which catalyzes the first reaction of the NAD + salvage pathway. This recombinant enzyme has a high catalytic activity against nicotinamide ( K m of 17 μM, k cat of 50 s -1 , k cat / K m of 3.0 × 10 3 s -1 · mM -1 ). Deletion of this gene abolished nicotinamide deamination activity in crude extracts of T. thermophilus and disrupted the NAD + salvage pathway in T. thermophilus Disruption of the salvage pathway led to the severe growth retardation at a higher temperature (80°C), owing to the drastic decrease in the intracellular concentrations of NAD + and NADH. IMPORTANCE NAD + and other nicotinamide cofactors are essential for cell metabolism. These molecules are unstable and decompose, even under the physiological conditions in most organisms. Thermophiles can survive at high temperatures where NAD + decomposition is, in general, more rapid. This study emphasizes that NAD + instability and its homeostasis can be one of the important factors for thermophile survival in extreme temperatures. Copyright © 2017 American Society for Microbiology.

Effects of employing a 10B-carrier and manipulating intratumour hypoxia on local tumour response and lung metastatic potential in boron neutron capture therapy

Science.gov (United States)

Masunaga, S; Sakurai, Y; Tanaka, H; Suzuki, M; Liu, Y; Kondo, N; Maruhashi, A; Kinashi, Y; Ono, K

2012-01-01

Objectives To evaluate the effects of employing a 10B-carrier and manipulating intratumour hypoxia on local tumour response and lung metastatic potential in boron neutron capture therapy (BNCT) by measuring the response of intratumour quiescent (Q) cells. Methods B16-BL6 melanoma tumour-bearing C57BL/6 mice were continuously given 5-bromo-2′-deoxyuridine (BrdU) to label all proliferating (P) cells. The tumours received reactor thermal neutron beam irradiation following the administration of a 10B-carrier [L-para-boronophenylalanine-10B (BPA) or sodium mercaptoundecahydrododecaborate-10B (BSH)] in combination with an acute hypoxia-releasing agent (nicotinamide) or mild temperature hyperthermia (MTH). Immediately after the irradiation, cells from some tumours were isolated and incubated with a cytokinesis blocker. The responses of the Q and total (P+Q) cell populations were assessed based on the frequency of micronuclei using immunofluorescence staining for BrdU. In other tumour-bearing mice, macroscopic lung metastases were enumerated 17 days after irradiation. Results BPA-BNCT increased the sensitivity of the total tumour cell population more than BSH-BNCT. However, the sensitivity of Q cells treated with BPA was lower than that of BSH-treated Q cells. With or without a 10B–carrier, MTH enhanced the sensitivity of the Q cell population. Without irradiation, nicotinamide treatment decreased the number of lung metastases. With irradiation, BPA-BNCT, especially in combination with nicotinamide treatment, showed the potential to reduce the number of metastases more than BSH-BNCT. Conclusion BSH-BNCT in combination with MTH improves local tumour control, while BPA-BNCT in combination with nicotinamide may reduce the number of lung metastases. PMID:22391496

Effect of oxygen and nitroaromatic cell radiosensitizers on radiation-induced cleavage of internucleotide bonds: ApA, dApA, and poly(A)

International Nuclear Information System (INIS)

Raleigh, J.A.; Kremers, W.; Whitehouse, R.

1975-01-01

Irradiation of the dinucleoside monophosphates ApA and dApA in deoxygenated solution leads to a preferential cleavage of the 3' end of the internucleotide bond. Cleavage at the 3' bond is favored to the extent of 2 to 1 over 5' cleavage. Oxygen and nitroaromatic compounds inhibit 3' bond breaking in ApA and dApA in agreement with earlier findings from studies of 3'- and 5'-mononucleotides. In contrast to the mononucleotide results, no enhancement of 5' cleavage is observed for ApA and dApA irradiated in the presence of oxygen or the nitroaromatic additives. The over-all effect of the additives is to decrease the combined (3' and 5') yield of internucleotide bond breaking in ApA and dApA. This phenomenon is also observed for polyadenylic acid in the presence of the nitroaromatics. Oxygen marginally enhances internucleotide bond breaking in polyadenylic acid (factor 1.1) over that seen in deoxygenated solution. Postirradiation alkaline hydrolysis of dApA leads to further ester cleavage revealing the presence of radiation-induced alkali-labile bonds. The number of these bonds decreases in the order oxygen greater than nitrofurans greater than nitrobenzenes approximately irradiation in the absence of additives

The distribution of chromosome aberrations among chromosomes of karyotype in exposed human lymphocyte

International Nuclear Information System (INIS)

Que Tran; Tien Hoang Hung

1997-01-01

Induced chromosome aberrations (ch. ab.) in exposed Human peripheral blood lymphocyte have been used to assay radio.bio.doses, because of their characters such as: the maintaining Go phase in cell cycle in body, the distribution of cell in blood system and the distribution of ch. ab. in exposed cells of body and among chromosomes of karyotype. The frequency of ch. ab. reflected the quantity of radiation dose, dose rate and radiation energy. The dependence between radiation dose and frequency of ch. ab. was illustrated by the mathematic equations. The distribution of induced ch. ab. among the cells exposed to uniform radiation fields was Poisson's, but the distribution of ch. ab. among chromosomes in karyotype depended on radiation field and mononucleotid sequence of DNA molecular of each chromosome. The minimum influence of mononucleotid sequence of DNA molecular in inform ch. ab. will be advantageous state for dose-assessments. The location of induced ch. ab. in exposed Human lymphocyte had been determined by karyotype analyses. The data of statistic analyse had improved that the number of ch. ab. depended on the size of chromosomes in karyotype. The equal distribution of ch. ab.among chromosomes in karyotype provided the objectiveness and the accuracy of using the chromosomal aberrant analysis technique on bio-dosimetry. (author)

Structure-Based Optimization of Arylamides as Inhibitors of Soluble Epoxide Hydrolase

Energy Technology Data Exchange (ETDEWEB)

Eldrup, Anne B.; Soleymanzadeh, Fariba; Taylor, Steven J.; Muegge, Ingo; Farrow, Neil A.; Joseph, David; McKellop, Keith; Man, Chuk C.; Kukulka, Alison; De Lombaert, Stephane; (Boehringer)

2009-11-04

Inhibition of soluble epoxide hydrolase (sEH) is hypothesized to lead to an increase in circulating levels of epoxyeicosatrienoic acids, resulting in the potentiation of their in vivo pharmacological properties. As part of an effort to identify inhibitors of sEH with high and sustained plasma exposure, we recently performed a high throughput screen of our compound collection. The screen identified N-(3,3-diphenyl-propyl)-nicotinamide as a potent inhibitor of sEH. Further profiling of this lead revealed short metabolic half-lives in microsomes and rapid clearance in the rat. Consistent with these observations, the determination of the in vitro metabolic profile of N-(3,3-diphenyl-propyl)-nicotinamide in rat liver microsomes revealed extensive oxidative metabolism and a propensity for metabolite switching. Lead optimization, guided by the analysis of the solid-state costructure of N-(3,3-diphenyl-propyl)-nicotinamide bound to human sEH, led to the identification of a class of potent and selective inhibitors. An inhibitor from this class displayed an attractive in vitro metabolic profile and high and sustained plasma exposure in the rat after oral administration.

Increased de novo riboflavin synthesis and hydrolysis of FMN are involved in riboflavin secretion from Hyoscyamus albus hairy roots under iron deficiency

OpenAIRE

Higa, Ataru; Khandakar, Jebunnahar; Mori, Yuko; Kitamura, Yoshie

2012-01-01

Riboflavin secretion by Hyoscyamus albus hairy roots under Fe deficiency was examined to determine where riboflavin is produced and whether production occurs via an enhancement of riboflavin biosynthesis or a stimulation of flavin mononucleotide (FMN) hydrolysis. Confocal fluorescent microscopy showed that riboflavin was mainly localized in the epidermis and cortex of the root tip and, at the cellular level, in the apoplast. The expressions of three genes involved in the de novo biosynthesis ...

HepG2 cells develop signs of riboflavin deficiency within four days of culture in riboflavin-deficient medium*

OpenAIRE

Werner, Ricarda; Manthey, Karoline C.; Griffin, Jacob B.; Zempleni, Janos

2005-01-01

Flavin mononucleotide and flavin adenine dinucleotide are essential coenzymes in redox reactions. For example, flavin adenine dinucleotide is a coenzyme for both glutathione reductase and enzymes that mediate the oxidative folding of secretory proteins. Here we investigated short-term effects of moderately riboflavin-deficient culture medium on flavin-related responses in HepG2 hepatocarcinoma cells. Cells were cultured in riboflavin-deficient (3.1 nmol/L) medium for up to six days; controls ...

Genetic Control of Biosynthesis and Transport of Riboflavin and Flavin Nucleotides and Construction of Robust Biotechnological Producers†

OpenAIRE

Abbas, Charles A.; Sibirny, Andriy A.

2011-01-01

Summary: Riboflavin [7,8-dimethyl-10-(1′-d-ribityl)isoalloxazine, vitamin B2] is an obligatory component of human and animal diets, as it serves as the precursor of flavin coenzymes, flavin mononucleotide, and flavin adenine dinucleotide, which are involved in oxidative metabolism and other processes. Commercially produced riboflavin is used in agriculture, medicine, and the food industry. Riboflavin synthesis starts from GTP and ribulose-5-phosphate and proceeds through pyrimidine and pterid...

Determination and confirmation of nicotinic acid and its analogues and derivates in pear and apple blossoms using high-performance liquid chromatography-diode array-electrospray ionization mass spectrometry.

Science.gov (United States)

Paternoster, Thomas; Vrhovsek, Urska; Pertot, Ilaria; Duffy, Brion; Gessler, Cesare; Mattivi, Fulvio

2009-11-11

Erwinia amylovora causes fire blight, a serious disease of apple and pear. The bacterial pathogen colonizes the flower stigma and hypanthium, where it multiplies and then invades through natural openings (nectarthodes). E. amylovora requires nicotinic acid as growth factor, and competition for nicotinic acid is being explored as a novel biocontrol strategy. The ability of E. amylovora to substitute nicotinic acid with analogues or derivates as growth factors has not been investigated yet. Furthermore, the presence and/or variable concentration of nicotinic acid and its analogues/derivates in the hypanthium could be associated with the different susceptibilities to fire blight of hosts and nonhosts and with the differential sensitivity to the disease among apple and pear varieties. Currently, no methods to specifically quantify nicotinic acid and nicotinic acid analogues/derivates in the hypanthium of apple and pear blossoms are available. This study demonstrates that E. amylovora can grow using nicotinamide and 6-hydroxynicotinic acid as alternative growth factors to nicotinic acid, but not using 2-hydroxynicotinic acid. A novel HPLC/ES-MS method was developed for the detection and quantification of nicotinic acid and its analogues/derivates directly in the hypanthium of apple and pear blossoms. Analyses established the presence of nicotinic acid and nicotinamide, whereas no detectable amounts of 6-hydroxynicotinic acid and 2-hydroxynicotinic acid were observed. Mean nicotinic acid content in the pear hypanthium was found to be approximately 2 orders of magnitude higher than in the apple hypanthium, which may contribute to the differential susceptibility of these two host species to fire blight. Contents of nicotinamide were in contrast similar. Nicotinic acid can therefore be considered a relevant factor in the pathogen establishment in pear blossoms, whereas nicotinamide could cover a primary role in apple blossoms.

Effect of bevacizumab combined with boron neutron capture therapy on local tumor response and lung metastasis

Science.gov (United States)

MASUNAGA, SHIN-ICHIRO; SAKURAI, YOSHINORI; TANO, KEIZO; TANAKA, HIROKI; SUZUKI, MINORU; KONDO, NATSUKO; NARABAYASHI, MASARU; WATANABE, TSUBASA; NAKAGAWA, YOSUKE; MARUHASHI, AKIRA; ONO, KOJI

2014-01-01

The aim of the present study was to evaluate the effect of bevacizumab on local tumor response and lung metastatic potential during boron neutron capture therapy (BNCT) and in particular, the response of intratumor quiescent (Q) cells. B16-BL6 melanoma tumor-bearing C57BL/6 mice were continuously administered bromodeoxyuridine (BrdU) to label all proliferating (P) tumor cells. The tumors were irradiated with thermal neutron beams following the administration of a 10B-carrier [L-para-boronophenylalanine-10B (BPA) or sodium mercaptoundecahydrododecaborate-10B (BSH)], with or without the administration of bevacizumab. This was further combined with an acute hypoxia-releasing agent (nicotinamide) or mild temperature hyperthermia (MTH, 40°C for 60 min). Immediately following the irradiation, cells from certain tumors were isolated and incubated with a cytokinesis blocker. The responses of the Q cells and the total (P+Q) cell populations were assessed based on the frequency of micronuclei using immunofluorescence staining for BrdU. In other tumor-bearing mice, 17 days following irradiation, lung metastases were enumerated. Three days following bevacizumab administration, the sensitivity of the total tumor cell population following BPA-BNCT had increased more than that following BSH-BNCT. The combination with MTH, but not with nicotinamide, further enhanced total tumor cell population sensitivity. Regardless of the presence of a 10B-carrier, MTH enhanced the sensitivity of the Q cell population. Regardless of irradiation, the administration of bevacizumab, as well as nicotinamide treatment, demonstrated certain potential in reducing the number of lung metastases especially in BPA-BNCT compared with BSH-BNCT. Thus, the current study revealed that BNCT combined with bevacizumab has the potential to sensitize total tumor cells and cause a reduction in the number of lung metastases to a similar level as nicotinamide. PMID:24944637

Aptamer based fluorescent cocaine assay based on the use of graphene oxide and exonuclease III-assisted signal amplification

International Nuclear Information System (INIS)

Zhang, Yulin; Zhang, Guo-Jun; Sun, Zhongyue; Tang, Lina; Zhang, Hong

2016-01-01

The article reports an aptamer based assay for cocaine by employing graphene oxide and exonuclease III-assisted signal amplification. It is based on the following scheme and experimental steps: (1) Exo III can digest dsDNA with blunt or recessed 3-terminus, but it has limited activity to ssDNA or dsDNA with protruding 3-terminus; (2) GO can absorb the FAM-labeled ssDNA probe and quench the fluorescence of probe, while the affinity between FAM-labeled mononucleotide and GO is negligible; (3) Cocaine aptamer can be split into two flexible ssDNA pieces (Probe 1 and Probe 2) without significant perturbation of cocaine-binding abilities; (4) The triple complex consisting of Probe 1, Probe 2 and cocaine can be digested by Exo III with the similar efficiency as normal dsDNA. Cocaine aptamer is split into two flexible ssDNA pieces (Probe 2 and 3′-FAM-labeled Probe 1). Cocaine can mediate the cocaine aptamer fragments forming a triplex. The triple complex has unique characteristic with 3′-FAM-labeled blunt end at the Probe 1 and 3′-overhang end at Probe 2. If exonuclease III is added, it will catalyze the stepwise removal of fluorescein (FAM) labeled mononucleotides from the 3-hydroxy termini of the special triplex complex, resulting in liberation of cocaine. The cocaine released in this step can produce a new cleavage cycle, thereby leading to target recycling. Through such a cyclic bound-hydrolysis process, small amounts of cocaine can induce the cleavage of a large number of FAM-labeled probe 1. The cleaved FAM-labeled mononucleotides are not adsorbed on the surface of graphene oxide (GO), so a strong fluorescence signal enhancement is observed as the cocaine triggers enzymatic digestion. Under optimized conditions, the assay allows cocaine to be detected in the 1 to 500 nM concentration range with a detection limit of 0.1 nM. The method was applied to the determination of cocaine in spiked human plasma, with recoveries ranging from 92.0 to 111.8 % and RSD of <12

Metabolic engineering of Escherichia coli for the production of riboflavin

OpenAIRE

Lin, Zhenquan; Xu, Zhibo; Li, Yifan; Wang, Zhiwen; Chen, Tao; Zhao, Xueming

2014-01-01

Background Riboflavin (vitamin B2), the precursor of the flavin cofactors flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD), is used commercially as an animal feed supplement and food colorant. E. coli is a robust host for various genetic manipulations and has been employed for efficient production of biofuels, polymers, amino acids, and bulk chemicals. Thus, the aim of this study was to understand the metabolic capacity of E. coli for the riboflavin production by modification...

Inflames of confined space-hypoxia syndrome on riboflavin and its coenzymes content in white rat tissues

OpenAIRE

Федорко, Наталія Леонідівна; Прокоф’єва, Наталія Юріївна; Келар, Анастасія Едуардівна; Петров, Сергій Анатолійович

2015-01-01

During confined space-hypoxia syndrome it is observed a significant increase of riboflavin in all organs of rats, but more in the heart and brain. High level of flavin adenine dinucleotide is observed in rat liver and kidney, and significant increase of flavin mononucleotide is observed only in the brain. The data reflect the metabolism of riboflavin under conditions of confined space-hypoxia syndrome, and change of the flavin content in the bodies of animals indicates different compensatory ...

The Leishmania nicotinamidase is essential for NAD+ production and parasite proliferation.

Science.gov (United States)

Gazanion, E; Garcia, D; Silvestre, R; Gérard, C; Guichou, J F; Labesse, G; Seveno, M; Cordeiro-Da-Silva, A; Ouaissi, A; Sereno, D; Vergnes, B

2011-10-01

NAD+ is a central cofactor that plays important roles in cellular metabolism and energy production in all living cells. Genomics-based reconstruction of NAD+ metabolism revealed that Leishmania protozoan parasites are NAD+ auxotrophs. Consequently, these parasites require assimilating NAD+ precursors (nicotinamide, nicotinic acid, nicotinamide riboside) from their host environment to synthesize NAD+ by a salvage pathway. Nicotinamidase is a key enzyme of this salvage pathway that catalyses conversion of nicotinamide (NAm) to nicotinic acid (Na), and that is absent in higher eukaryotes. We present here the biochemical and functional characterizations of the Leishmania infantum nicotinamidase (LiPNC1). Generation of Lipnc1 null mutants leads to a decrease in NAD+ content, associated with a metabolic shutdown-like phenotype with an extensive lag phase of growth. Both phenotypes could be rescued by an add-back construct or by addition of exogenous Na. In addition, Lipnc1 null mutants were unable to establish a sustained infection in a murine experimental model. Altogether, these results illustrate that NAD+ homeostasis is a fundamental component of Leishmania biology and virulence, and that NAm constitutes its main NAD+ source in the mammalian host. The crystal structure of LiPNC1 we solved allows now the design of rational inhibitors against this new promising therapeutic target. © 2011 Blackwell Publishing Ltd.

General and efficient one-pot synthesis of novel sugar/heterocyclic(aryl) 1,2-diketones from sugar terminal alkynes by Sonogashira/tetra-n- butylammonium permanganate oxidation.

Science.gov (United States)

Zhang, Fuyi; Wu, Xiaopei; Wang, Liming; Liu, Hong; Zhao, Yufen

2015-11-19

A new approach for one-pot synthesis of novel sugar/heterocyclic(aryl) 1,2-diketones has been achieved by the reaction of various sugar terminal alkynes with heterocyclic(aryl) iodides at room temperature. This one-pot protocol includes Sonogashira coupling and mild n-Bu4NMnO4 oxidation reaction. This method is mild, general and efficient. Fifty-six examples have been given and the sugar/heterocyclic(aryl) 1,2-diketones were obtained in 71-94% yields. The sugar terminal alkynes include 9 structurally different sugars in pyranose, furanose, and acyclic form which have various protecting groups, sensitive groups, and sterically bulky substituents. The heterocyclic(aryl) iodides include sterically bulky heterocyclic compounds and iodobenzenes with electron-donating, electron-neutral, and electron-withdrawing substituents. Copyright © 2015 Elsevier Ltd. All rights reserved.

Depletion of NAD pool contributes to impairment of endothelial progenitor cell mobilization in diabetes.

Science.gov (United States)

Wang, Pei; Yang, Xi; Zhang, Zheng; Song, Jie; Guan, Yun-Feng; Zou, Da-Jin; Miao, Chao-Yu

2016-06-01

The impaired mobilization of endothelial progenitor cells (EPCs) from bone marrow (BM) critically contributes to the diabetes-associated vascular complications. Here, we investigated the relationship between the nicotinamide phosphoribosyltransferase (NAMPT)-controlled nicotinamide adenine dinucleotide (NAD) metabolism and the impaired mobilization of BM-derived EPCs in diabetic condition. The NAMPT-NAD pool in BM and BM-derived EPCs in wild-type (WT) and diabetic db/db mice was determined. Nicotinamide, a natural substrate for NAD biosynthesis, was administrated for 2weeks in db/db mice to examine the influence of enhancing NAD pool on BM and blood EPCs number. The modulations of stromal cell-derived factor-1α (SDF-1α) and endothelial nitric oxide synthase (eNOS) protein in BM were measured using immunoblotting. The EPCs intracellular NAMPT level and NAD concentration, as well as the blood EPCs number, were compared between 9 healthy people and 16 patients with type 2 diabetes mellitus (T2DM). The T2DM patients were treated with nicotinamide for two weeks and then the blood EPCs number was determined. Moreover, the association between blood EPCs numbers and EPCs intracellular NAD(+)/NAMPT protein levels in 21 healthy individuals was determined. We found that NAD concentration and NAMPT expression in BM and BM-derived EPCs of db/db mice were significantly lower than those in WT mice BM. Enhancing NAD pool not only increased the EPCs intracellular NAD concentration and blood EPCs number, but also improved post-ischemic wound healing and blood reperfusion in db/db mice with hind-limb ischemia model. Enhancing NAD pool rescued the impaired modulations of stromal cell-derived factor-1α (SDF-1α) and endothelial nitric oxide synthase (eNOS) protein levels in db/db mice BM upon hind-limb ischemia. In addition, enhancing NAD pool significantly inhibited PARP and caspase-3 activates in db/db mice BM. The intracellular NAMPT-NAD pool was positively associated with blood

Actions of p-synephrine on hepatic enzyme activities linked to carbohydrate metabolism and ATP levels in vivo and in the perfused rat liver.

Science.gov (United States)

Maldonado, Marcos Rodrigues; Bracht, Lívia; de Sá-Nakanishi, Anacharis Babeto; Corrêa, Rúbia Carvalho Gomes; Comar, Jurandir Fernando; Peralta, Rosane Marina; Bracht, Adelar

2018-01-01

p-Synephrine is one of the main active components of the fruit of Citrus aurantium (bitter orange). Extracts of the bitter orange and other preparations containing p-synephrine have been used worldwide to promote weight loss and for sports performance. The purpose of the study was to measure the action of p-synephrine on hepatic enzyme activities linked to carbohydrate and energy metabolism and the levels of adenine mononucleotides. Enzymes and adenine mononucleotides were measured in the isolated perfused rat liver and in vivo after oral administration of the drug (50 and 300 mg/kg) by using standard techniques. p-Synephrine increased the activity of glycogen phosphorylase in vivo and in the perfused liver. It decreased, however, the activities of pyruvate kinase and pyruvate dehydrogenase also in vivo and in the perfused liver. p-Synephrine increased the hepatic pools of adenosine diphosphate and adenosine triphosphate. Stimulation of glycogen phosphorylase is consistent with the reported increased glycogenolysis in the perfused liver and increased glycemia in rats. The decrease in the pyruvate dehydrogenase activity indicates that p-synephrine is potentially capable of inhibiting the transformation of carbohydrates into lipids. The capability of increasing the adenosine triphosphate-adenosine diphosphate pool indicates a beneficial effect of p-synephrine on the cellular energetics. Copyright © 2017 John Wiley & Sons, Ltd.

Infrequent widespread microsatellite instability in hepatocellular carcinomas.

Science.gov (United States)

Yamamoto, H; Itoh, F; Fukushima, H; Kaneto, H; Sasaki, S; Ohmura, T; Satoh, T; Karino, Y; Endo, T; Toyota, J; Imai, K

2000-03-01

Widespread or high-frequency microsatellite instability (MSI) due to the defective DNA mismatch repair (MMR) occurs in the majority of hereditary non-polyposis colorectal cancer and a subset of sporadic malignant tumors. The incidence of MSI and underlying DNA MMR defects have been well characterized in gastrointestinal carcinogenesis, but not in hepatocarcinogenesis. To address the issue, we analyzed 55 Japanese hepatocellular carcinomas using several indicators of DNA MMR defects, such as microsatellite analysis, loss of heterozygosity (LOH) and mutation analysis of MMR genes, methylation of hMLH1 promoter, and frameshift mutations of mononucleotide repeat sequences within possible target genes. Mutation of beta2-microglobulin gene, which is presumably involved in MSI-positive tumor cell escape from immune surveillance was also examined. Some of these analyses were also carried out in 9 human liver cancer cell lines. None of the 3 quasi-monomorphic mononucleotide markers sensitive for MSI, BAT26, BAT25, and BAT34C4 presented shortened unstable alleles in any of the carcinoma, cirrhosis, chronic hepatitis tissues, or cell lines. LOH at MMR genes was infrequent (4.4 approximately 7.1%), and no mutations were detected. Neither hMLH1 hypermethylation nor frameshift mutation in the target genes was detected. No mutations were found in beta2-microglobulin. Widespread MSI due to the defective DNA MMR appears to play little if any part in Japanese hepatocarcinogenesis.

Crystal structure of the bacterial luciferase/flavin complex provides insight into the function of the beta subunit.

Science.gov (United States)

Campbell, Zachary T; Weichsel, Andrzej; Montfort, William R; Baldwin, Thomas O

2009-07-07

Bacterial luciferase from Vibrio harveyi is a heterodimer composed of a catalytic alpha subunit and a homologous but noncatalytic beta subunit. Despite decades of enzymological investigation, structural evidence defining the active center has been elusive. We report here the crystal structure of V. harveyi luciferase bound to flavin mononucleotide (FMN) at 2.3 A. The isoalloxazine ring is coordinated by an unusual cis-Ala-Ala peptide bond. The reactive sulfhydryl group of Cys106 projects toward position C-4a, the site of flavin oxygenation. This structure also provides the first data specifying the conformations of a mobile loop that is crystallographically disordered in both prior crystal structures [(1995) Biochemistry 34, 6581-6586; (1996) J. Biol. Chem. 271, 21956 21968]. This loop appears to be a boundary between solvent and the active center. Within this portion of the protein, a single contact was observed between Phe272 of the alpha subunit, not seen in the previous structures, and Tyr151 of the beta subunit. Substitutions at position 151 on the beta subunit caused reductions in activity and total quantum yield. Several of these mutants were found to have decreased affinity for reduced flavin mononucleotide (FMNH(2)). These findings partially address the long-standing question of how the beta subunit stabilizes the active conformation of the alpha subunit, thereby participating in the catalytic mechanism.

Genome-Wide Characterization of Simple Sequence Repeat (SSR) Loci in Chinese Jujube and Jujube SSR Primer Transferability

Science.gov (United States)

Xiao, Jing; Zhao, Jin; Liu, Mengjun; Liu, Ping; Dai, Li; Zhao, Zhihui

2015-01-01

Chinese jujube (Ziziphus jujuba), an economically important species in the Rhamnaceae family, is a popular fruit tree in Asia. Here, we surveyed and characterized simple sequence repeats (SSRs) in the jujube genome. A total of 436,676 SSR loci were identified, with an average distance of 0.93 Kb between the loci. A large proportion of the SSRs included mononucleotide, dinucleotide and trinucleotide repeat motifs, which accounted for 64.87%, 24.40%, and 8.74% of all repeats, respectively. Among the mononucleotide repeats, A/T was the most common, whereas AT/TA was the most common dinucleotide repeat. A total of 30,565 primer pairs were successfully designed and screened using a series of criteria. Moreover, 725 of 1,000 randomly selected primer pairs were effective among 6 cultivars, and 511 of these primer pairs were polymorphic. Sequencing the amplicons of two SSRs across three jujube cultivars revealed variations in the repeats. The transferability of jujube SSR primers proved that 35/64 SSRs could be transferred across family boundary. Using jujube SSR primers, clustering analysis results from 15 species were highly consistent with the Angiosperm Phylogeny Group (APGIII) System. The genome-wide characterization of SSRs in Chinese jujube is very valuable for whole-genome characterization and marker-assisted selection in jujube breeding. In addition, the transferability of jujube SSR primers could provide a solid foundation for their further utilization. PMID:26000739

Sylwan manuscript revised

African Journals Online (AJOL)

이영준

mature adipocytes and accumulate lipids, as an obesity model with cytotoxicity and ... 2,5-diphenyltetrazolium Bromide; NAC = N-acetyl-L-cysteine; NADPH = Nicotinamide adenine dinucleotide phosphate; OD = ..... ovariectomized rats.

Simvastatin-nicotinamide co-crystal: design, preparation and ...

African Journals Online (AJOL)

Methods: In silico molecular modeling of Nic counter to SV were investigated using Auto Dock 4.2. ... XRPD, DSC, FT-IR, and binary phase diagram indicate the formation of a new ... (CHARMM forced field was applied for energy .... The thermograms (Figure 8) showed no change ... for providing some materials for the study.

Simvastatin-nicotinamide co-crystal: design, preparation and ...

African Journals Online (AJOL)

Methods: In silico molecular modeling of Nic counter to SV were investigated using ... Results: In silico results showed that the interaction of Nic with SV took place through ... Conclusion: Co-crystallization using Nic has the potential to enhance drug ... directed to convert the ligand protein data bank ... after each sampling.

Inflames of confined space-hypoxia syndrome on riboflavin and its coenzymes content in white rat tissues

Directory of Open Access Journals (Sweden)

Наталія Леонідівна Федорко

2015-08-01

Full Text Available During confined space-hypoxia syndrome it is observed a significant increase of riboflavin in all organs of rats, but more in the heart and brain. High level of flavin adenine dinucleotide is observed in rat liver and kidney, and significant increase of flavin mononucleotide is observed only in the brain. The data reflect the metabolism of riboflavin under conditions of confined space-hypoxia syndrome, and change of the flavin content in the bodies of animals indicates different compensatory processes

pH-tuneable binding of 2'-phospho-ADP-ribose to ketopantoate reductase: a structural and calorimetric study.

Science.gov (United States)

Ciulli, Alessio; Lobley, Carina M C; Tuck, Kellie L; Smith, Alison G; Blundell, Tom L; Abell, Chris

2007-02-01

The crystal structure of Escherichia coli ketopantoate reductase in complex with 2'-monophosphoadenosine 5'-diphosphoribose, a fragment of NADP+ that lacks the nicotinamide ring, is reported. The ligand is bound at the enzyme active site in the opposite orientation to that observed for NADP+, with the adenine ring occupying the lipophilic nicotinamide pocket. Isothermal titration calorimetry with R31A and N98A mutants of the enzyme is used to show that the unusual ;reversed binding mode' observed in the crystal is triggered by changes in the protonation of binding groups at low pH. This research has important implications for fragment-based approaches to drug design, namely that the crystallization conditions and the chemical modification of ligands can have unexpected effects on the binding modes.

The Role of Pyruvate Dehydrogenase Kinase in Diabetes and Obesity

Directory of Open Access Journals (Sweden)

In-Kyu Lee

2014-06-01

Full Text Available The pyruvate dehydrogenase complex (PDC is an emerging target for the treatment of metabolic syndrome. To maintain a steady-state concentration of adenosine triphosphate during the feed-fast cycle, cells require efficient utilization of fatty acid and glucose, which is controlled by the PDC. The PDC converts pyruvate, coenzyme A (CoA, and oxidized nicotinamide adenine dinucleotide (NAD+ into acetyl-CoA, reduced form of nicotinamide adenine dinucleotide (NADH, and carbon dioxide. The activity of the PDC is up- and down-regulated by pyruvate dehydrogenase kinase and pyruvate dehydrogenase phosphatase, respectively. In addition, pyruvate is a key intermediate of glucose oxidation and an important precursor for the synthesis of glucose, glycerol, fatty acids, and nonessential amino acids.

Exploring encapsulation mechanism of DNA and mononucleotides in sol-gel derived silica.

Science.gov (United States)

Kapusuz, Derya; Durucan, Caner

2017-07-01

The encapsulation mechanism of DNA in sol-gel derived silica has been explored in order to elucidate the effect of DNA conformation on encapsulation and to identify the nature of chemical/physical interaction of DNA with silica during and after sol-gel transition. In this respect, double stranded DNA and dAMP (2'-deoxyadenosine 5'-monophosphate) were encapsulated in silica using an alkoxide-based sol-gel route. Biomolecule-encapsulating gels have been characterized using UV-Vis, 29 Si NMR, FTIR spectroscopy and gas adsorption (BET) to investigate chemical interactions of biomolecules with the porous silica network and to examine the extent of sol-gel reactions upon encapsulation. Ethidium bromide intercalation and leach out tests showed that helix conformation of DNA was preserved after encapsulation. For both biomolecules, high water-to-alkoxide ratio promoted water-producing condensation and prevented alcoholic denaturation. NMR and FTIR analyses confirmed high hydraulic reactivity (water adsorption) for more silanol groups-containing DNA and dAMP encapsulated gels than plain silica gel. No chemical binding/interaction occurred between biomolecules and silica network. DNA and dAMP encapsulated silica gelled faster than plain silica due to basic nature of DNA or dAMP containing buffer solutions. DNA was not released from silica gels to aqueous environment up to 9 days. The chemical association between DNA/dAMP and silica host was through phosphate groups and molecular water attached to silanols, acting as a barrier around biomolecules. The helix morphology was found not to be essential for such interaction. BET analyses showed that interconnected, inkbottle-shaped mesoporous silica network was condensed around DNA and dAMP molecules.

Biodegradation of 2,4-dichlorophenol using Mycoplana dimorpha ...

African Journals Online (AJOL)

STORAGESEVER

2008-06-17

Jun 17, 2008 ... dation kinetic models have been developed, proposed and used in ... kinetic models. ..... Dihydroxycyclohexa-3, 5-Diene (Nicotinamide Adenine Dinucleotide) .... (KMUP-3) in rat trachea: The involvement of soluble guanylate.

Essential role of Bordetella NadC in a quinolinate salvage pathway for NAD biosynthesis.

Science.gov (United States)

Brickman, Timothy J; Suhadolc, Ryan J; McKelvey, Pamela J; Armstrong, Sandra K

2017-02-01

Nicotinamide adenine dinucleotide (NAD) is produced via de novo biosynthesis pathways and by salvage or recycling routes. The classical Bordetella bacterial species are known to be auxotrophic for nicotinamide or nicotinic acid. This study confirmed that Bordetella bronchiseptica, Bordetella pertussis and Bordetella parapertussis have the recycling/salvage pathway genes pncA and pncB, for use of nicotinamide or nicotinic acid, respectively, for NAD synthesis. Although these Bordetellae lack the nadA and nadB genes needed for de novo NAD biosynthesis, remarkably, they have one de novo pathway gene, nadC, encoding quinolinate phosphoribosyltransferase. Genomic analyses of taxonomically related Bordetella and Achromobacter species also indicated the presence of an 'orphan' nadC and the absence of nadA and nadB. When supplied as the sole NAD precursor, quinolinate promoted B. bronchiseptica growth, and the ability to use it required nadC. Co-expression of Bordetella nadC with the nadB and nadA genes of Paraburkholderia phytofirmans allowed B. bronchiseptica to grow in the absence of supplied pyridines, indicative of de novo NAD synthesis and functional confirmation of Bordetella NadC activity. Expression of nadC in B. bronchiseptica was influenced by nicotinic acid and by a NadQ family transcriptional repressor, indicating that these organisms prioritize their use of pyridines for NAD biosynthesis. © 2016 John Wiley & Sons Ltd.

Identification of novel resistance mechanisms to NAMPT inhibition via the de novo NAD+ biosynthesis pathway and NAMPT mutation.

Science.gov (United States)

Guo, Jun; Lam, Lloyd T; Longenecker, Kenton L; Bui, Mai H; Idler, Kenneth B; Glaser, Keith B; Wilsbacher, Julie L; Tse, Chris; Pappano, William N; Huang, Tzu-Hsuan

2017-09-23

Cancer cells have an unusually high requirement for the central and intermediary metabolite nicotinamide adenine dinucleotide (NAD + ), and NAD + depletion ultimately results in cell death. The rate limiting step within the NAD + salvage pathway required for converting nicotinamide to NAD + is catalyzed by nicotinamide phosphoribosyltransferase (NAMPT). Targeting NAMPT has been investigated as an anti-cancer strategy, and several highly selective small molecule inhibitors have been found to potently inhibit NAMPT in cancer cells, resulting in NAD + depletion and cytotoxicity. To identify mechanisms that could cause resistance to NAMPT inhibitor treatment, we generated a human fibrosarcoma cell line refractory to the highly potent and selective NAMPT small molecule inhibitor, GMX1778. We uncovered novel and unexpected mechanisms of resistance including significantly increased expression of quinolinate phosphoribosyl transferase (QPRT), a key enzyme in the de novo NAD + synthesis pathway. Additionally, exome sequencing of the NAMPT gene in the resistant cells identified a single heterozygous point mutation that was not present in the parental cell line. The combination of upregulation of the NAD + de novo synthesis pathway through QPRT over-expression and NAMPT mutation confers resistance to GMX1778, but the cells are only partially resistant to next-generation NAMPT inhibitors. The resistance mechanisms uncovered herein provide a potential avenue to continue exploration of next generation NAMPT inhibitors to treat neoplasms in the clinic. Copyright © 2017 Elsevier Inc. All rights reserved.

Modulation of glucose uptake in adipose tissue by nitric oxide ...

Indian Academy of Sciences (India)

Madhu

ion-dependent breakdown and trans-nitrosation reactions are ... [McGrowder D, Ragoobirsingh D and Brown P 2006 Modulation of glucose uptake in adipose tissue by nitric oxide-generating ... Briefly, nicotinamide (Sigma Chemical Co.,.

Thermoanalytical investigation and biological properties of zinc(II) 4-chloro- and 5-chlorosalicylates with N-donor ligands

Czech Academy of Sciences Publication Activity Database

Bujdošová, Z.; Györyová, K.; Mudroňová, D.; Hudecová, D.; Kovářová, Jana

2012-01-01

Roč. 110, č. 1 (2012), s. 167-176 ISSN 1388-6150 Institutional support: RVO:61389013 Keywords : chlorosalicylate * zinc(II) * nicotinamide derivatives Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.982, year: 2012

Do diosgenin ameliorate urinary bladder toxic effect of ...

African Journals Online (AJOL)

SWEET

2012-01-26

Jan 26, 2012 ... experimental animal models? ... BSO doses using a Swiss albino mouse model. Toxicity modulation ... bladder inflammation induced by CP in rats and mice .... 0.1 ml NADPH (nicotinamide adenine dinucleotide phosphate.

Effects of vacuum ultraviolet radiation on deoxyoligonucleotides in solids in the wavelength region around and above ionization potential -with special reference to the chain scission

International Nuclear Information System (INIS)

Ito, Takashi; Saito, Mikio

1991-01-01

Photoproducts arising from exposure of deoxyoligonucleotides of adenine, d(pA) n (n = 2 ∼ 5), as solids to vacuum-u.v. radiation at the wavelengths around and above ionization potential were analyzed by thin-layer chromatography. The main decomposition products were identified as adenine and all possible oligonucleotide and mononucleotide components for k satisfying n - k ≥ 1. These results and previous findings on the related compounds were discussed with special reference to the rules on the induction of chain scission by superexcitation. (author)

Pyridine nucleotide cycling and control of intracellular redox state in relation to poly (ADP-ribose) polymerase activity and nuclear localization of glutathione during exponential growth of Arabidopsis cells in culture.

Science.gov (United States)

Pellny, Till K; Locato, Vittoria; Vivancos, Pedro Diaz; Markovic, Jelena; De Gara, Laura; Pallardó, Federico V; Foyer, Christine H

2009-05-01

Pyridine nucleotides, ascorbate and glutathione are major redox metabolites in plant cells, with specific roles in cellular redox homeostasis and the regulation of the cell cycle. However, the regulation of these metabolite pools during exponential growth and their precise functions in the cell cycle remain to be characterized. The present analysis of the abundance of ascorbate, glutathione, and pyridine nucleotides during exponential growth of Arabidopsis cells in culture provides evidence for the differential regulation of each of these redox pools. Ascorbate was most abundant early in the growth cycle, but glutathione was low at this point. The cellular ascorbate to dehydroascorbate and reduced glutathione (GSH) to glutathione disulphide ratios were high and constant but the pyridine nucleotide pools were largely oxidized over the period of exponential growth and only became more reduced once growth had ceased. The glutathione pool increased in parallel with poly (ADP-ribose) polymerase (PARP) activities and with increases in the abundance of PARP1 and PARP2 mRNAs at a time of high cell cycle activity as indicated by transcriptome information. Marked changes in the intracellular partitioning of GSH between the cytoplasm and nucleus were observed. Extension of the exponential growth phase by dilution or changing the media led to increases in the glutathione and nicotinamide adenine dinucleotide, oxidized form (NAD)-plus-nicotinamide adenine dinucleotide, reduced form (NADH) pools and to higher NAD/NADH ratios but the nicotinamide adenine dinucleotide phosphate, oxidized form (NADP)-plus-nicotinamide adenine dinucleotide phosphate, reduced form (NADPH) pool sizes, and NAPD/NADPH ratios were much less affected. The ascorbate, glutathione, and pyridine nucleotide pools and PARP activity decreased before the exponential growth phase ended. We conclude that there are marked changes in intracellular redox state during the growth cycle but that redox homeostasis is

Mellem et al., Afr J Tradit Complement Altern Med. (2015) 12(1):38 ...

African Journals Online (AJOL)

cadewumi

2010). Antihyperglycemic, antihyperlipidemic and antioxidant effects and the probable mechanism of action of Ruta graveolens infusion and rutin in nicotinamide-streptozotocin-induced diabetic rats. Diabetol. Croat. 39: 15-35. 2. Ali, H., Houghton ...

Thermal behaviour and antimicrobial assay of some new zinc(II) 2-aminobenzoate complex compounds with bioactive ligands

Czech Academy of Sciences Publication Activity Database

Krajníková, A.; Rotaru, A.; Györyová, K.; Homzová, K.; Manolea, H. O.; Kovářová, Jana; Hudecová, D.

2015-01-01

Roč. 120, č. 1 (2015), s. 73-83 ISSN 1388-6150 Institutional support: RVO:61389013 Keywords : antimicrobial * nicotinamide derivatives * non-isothermal kinetics Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.781, year: 2015

Chromium uptake by Saccharomyces cerevisiae and isolation of ...

Indian Academy of Sciences (India)

Unknown

In most models two nicotinate ligands are ... However, both biological extracts and synthetic GTF models have ..... chromium (III)-β-nicotinamide adenine dinucleotide phos- ... and free fatty acids levels in diabetic rats; J. Inorg. Biochem.

Development and evaluation of an in vivo assay in Caenorhabditis ...

Indian Academy of Sciences (India)

Madhu urs

1. Introduction. Cytochrome P450 enzymes (CYPs) are nicotinamide adenine .... guinea pig and rat are not amenable for high-throughput screening. Therefore, there ... model that is inexpensive and suitable for high-throughput drug screening.

Biokemistri

African Journals Online (AJOL)

Chibuike

2011-12-31

Dec 31, 2011 ... domain housing the nicotinamide adenine dinucleotide (NAD)- binding site and the ..... compared to wild-type animals, in experimental models of excitotoxicity .... Factor during transient focal cerebral ischemia in rat. Brain Res.

pH-tuneable binding of 2′-phospho-ADP-ribose to ketopantoate reductase: a structural and calorimetric study

Science.gov (United States)

Ciulli, Alessio; Lobley, Carina M. C.; Tuck, Kellie L.; Smith, Alison G.; Blundell, Tom L.; Abell, Chris

2007-01-01

The crystal structure of Escherichia coli ketopantoate reductase in complex with 2′-monophosphoadenosine 5′-diphosphoribose, a fragment of NADP+ that lacks the nicotinamide ring, is reported. The ligand is bound at the enzyme active site in the opposite orientation to that observed for NADP+, with the adenine ring occupying the lipophilic nicotinamide pocket. Isothermal titration calorimetry with R31A and N98A mutants of the enzyme is used to show that the unusual ‘reversed binding mode’ observed in the crystal is triggered by changes in the protonation of binding groups at low pH. This research has important implications for fragment-based approaches to drug design, namely that the crystallization conditions and the chemical modification of ligands can have unexpected effects on the binding modes. PMID:17242510

The effect of blood ozonation on mitochondrial function and ...

African Journals Online (AJOL)

SERVER

2007-08-06

Aug 6, 2007 ... form); NAD+, nicotinamide adenine dinucleotide (oxidised form);. ROS, reactive .... Isolation of rat liver mitochondria. Liver from healthy ... Respiration was measured using a MitocellTM (model MT 200) oxy- gen electrode and ...

Chemopreventive Effect of Tadalafil in Cisplatin-Induced ...

African Journals Online (AJOL)

olayemitoyin

mgkg-1 and 5 mgkg-1 of Tadalafil in cisplatin-induced nephrotoxic rats. In this study, twenty-five male ... mitochondria, and reduced nicotinamide adenine dinucletide .... Laboratory Centrifuge (Model SM 112, Surgifriend. Medicals, England) at ...

Protective effect of Euphorbia neriifolia saponin fraction on CCl 4 ...

African Journals Online (AJOL)

Jane

2010-10-18

Oct 18, 2010 ... ALP, alkaline phosphatase; NAD, nicotinamide adenine dinucleotide .... Laboratory bred Wistar albino rats of both sexes (150 - 200 g) were maintained .... experimental animals is a commonly used model for the screening of ...

Decreased visfatin after exercise training correlates with improved glucose tolerance

DEFF Research Database (Denmark)

Haus, Jacob M; Solomon, Thomas; Marchetti, Christine M

2009-01-01

Nampt/pre-B-cell colony-enhancing factor/visfatin (visfatin) release from adipocytes has recently been suggested to be nutrient responsive and linked to systemic nicotinamide adenine dinucleotide biosynthesis and regulation of pancreatic beta-cell function....

Abiotic Synthesis of Nucleic Acids: Hypochromicity and Future Research

Science.gov (United States)

Glass, K.; Oye, M.; Deamer, D.; Vercoutere, W.

2017-01-01

The earliest forms of life would likely have a protocellular form, with a membrane encapsulating some form of linear charged polymer. These polymers could have enzymatic as well as genetic properties. We can simulate plausible prebiotic conditions in the laboratory to test hypotheses related to this concept. In earlier work we have shown that mononucleotides organized within a multilamellar lipid matrix can produce oligomers in the anhydrous phase of dehydration- rehydration cycles (Rajamani, 2008). If mononucleotides are in solution at millimolar concentrations, then oligomers resembling RNA are synthesized and exist in a steady state with their monomers DeGuzman, 2014). We have used conventional and novel techniques to demonstrate that secondary structures stabilized by hydrogen bonds may be present in the condensation products produced in dehydration- rehydration cycles that simulate hydrothermal fields that were present on the early Earth. Gel electrophoresis data corroborates the presence of up to 200-base pair length RNA fragments in products of Hydration-Dehydration experiments. Furthermore, hypochromicity measurements demonstrate a degree of hypochromicity found in single RNA strand of known sequence, as well as results that indicate this is true also for a sample of complementary strands of RNA. Analysis of ionic current signatures of known RNA hairpin molecule as measured using a nanopore detector indicate a significant variability in pattern, different from the signatures produced by DNA hairpin molecules. This informs how we may interpret nanopore data gathered from prebiotic simulations.

Intracellular NAD(H) levels control motility and invasion of glioma cells.

NARCIS (Netherlands)

Horssen, R. van; Willemse, M.P.; Haeger, A.; Attanasio, F.; Guneri, T.; Schwab, A.; Stock, C.M.; Buccione, R.; Fransen, J.A.M.; Wieringa, B.

2013-01-01

Oncogenic transformation involves reprogramming of cell metabolism, whereby steady-state levels of intracellular NAD(+) and NADH can undergo dramatic changes while ATP concentration is generally well maintained. Altered expression of nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting

Current Concepts of Hyperinflammation in Chronic Granulomatous Disease

NARCIS (Netherlands)

Rieber, Nikolaus; Hector, Andreas; Kuijpers, Taco; Roos, Dirk; Hartl, Dominik

2012-01-01

Chronic granulomatous disease (CGD) is the most common inherited disorder of phagocytic functions, caused by genetic defects in the leukocyte nicotinamide dinucleotide phosphate (NADPH) oxidase. Consequently, CGD phagocytes are impaired in destroying phagocytosed microorganisms, rendering the

Fulltext PDF

Indian Academy of Sciences (India)

Madhsudhan

in the rat vitamin C is synthesised from glucose via the glucuronic pathway of ..... guinea pig model, we have demonstrated that moderately large doses of vitamin C ... of nicotinamide adenine dinucleotide phosphate (NADPH) to microsomal ...

The role of exogenous electron carriers in NAD(P)-dependent dehydrogenase cytochemistry studied in vitro and with a model system of polyacrylamide films

NARCIS (Netherlands)

van Noorden, C. J.; Tas, J.

1982-01-01

The applicability of phenazine methosulfate, 1-methoxyphenazine methosulfate, menadione, and meldola blue as exogenous electron carriers for the cytochemical staining of nicotinamide adenine dinucleotide (phosphate) (NAD(P))-dependent dehydrogenases has been studied quantitatively with tetranitro BT

Light production in the luminous fishes Photoblepharon and Anomalops from the Banda Islands.

Science.gov (United States)

Haneda, Y; Tsuji, F I

1971-07-09

The unresolved mechanism of light production in Photoblepharon and Anomalops has been reinvestigated in fresh and preserved material. Based on biochemical evidence obtained with emulsions and cell-free extracts of the organs, especially the stimulation of light with reduced flavin mononucleotide, and on electron microscopy of organ sections showing the presence of numerous bacteria, we conclude that the light is produced by symbiotic luminous bacteria. Because of the continuing failure to cultivate the luminous bacteria and because of their morphology, we suggest that the bacteria are of a primitive type called bacteroids.

DEOXYRIBONUCLEASE IV: A NEW EXONUCLEASE FROM MAMMALIAN TISSUES*

Science.gov (United States)

Lindahl, Tomas; Gally, Joseph A.; Edelman, Gerald M.

1969-01-01

An exonuclease which specifically degrades double-standard DNA has been isolated from rabbit tissues. The enzyme has an approximate molecular weight of 42,000, requires a divalent metal ion as cofactor, and attacks DNA at the 5′-terminal ends, thereby liberating 5′-mononucleotides. It degrades several synthetic polydeoxynucleotides of single repeating base sequences more rapidly than DNA from natural sources. The specificity of this mammalian enzyme resembles that of several microbial enzymes (phage λ exonuclease and DNA polymerase) which appear to be required for repair and recombination of DNA. PMID:5256235

Identification and cloning of four riboswitches from Burkholderia pseudomallei strain K96243

Science.gov (United States)

Munyati-Othman, Noor; Fatah, Ahmad Luqman Abdul; Piji, Mohd Al Akmarul Fizree Bin Md; Ramlan, Effirul Ikhwan; Raih, Mohd Firdaus

2015-09-01

Structured RNAs referred as riboswitches have been predicted to be present in the genome sequence of Burkholderia pseudomallei strain K96243. Four of the riboswitches were identified and analyzed through BLASTN, Rfam search and multiple sequence alignment. The RNA aptamers belong to the following riboswitch classifications: glycine riboswitch, cobalamin riboswitch, S-adenosyl-(L)-homocysteine (SAH) riboswitch and flavin mononucleotide (FMN) riboswitch. The conserved nucleotides for each aptamer were identified and were marked on the secondary structure generated by RNAfold. These riboswitches were successfully amplified and cloned for further study.

Three cases of intentional isoniazid overdose – a life-threatening ...

African Journals Online (AJOL)

. Lactic acidosis is thought to occur by INH inhibition of lactate dehydrogenase via its effect on the co-enzyme nicotinamide adenine dinucleotide. This is exacerbated by increased lactate production during seizures. For the management of an ...

Niacinamide

Science.gov (United States)

3-Pyridine Carboxamide, 3-Pyridinecarboxamide, Amide de l'Acide Nicotinique, B Complex Vitamin, Complexe de Vitamines B, Niacinamida, Nicamid, Nicosedine, Nicotinamide, Nicotinic Acid Amide, Nicotylamidum, Pyridine-3-carboxamide, Vitamin B3, Vitamina B3, Vitamine B3.

Energy-responsive timekeeping

Indian Academy of Sciences (India)

2008-12-31

Dec 31, 2008 ... involved lesions of the parabrachial nucleus in rats (David- son et al. 2000); however .... loops (figure 2). The current model involves a primary loop with CLOCK and .... of reduced to oxidized nicotinamide adenine dinucleotide.

Original Article Pubertal Development of Penile Nitric Oxide ...

African Journals Online (AJOL)

mn

penile tissue in different age groups in the rat and to measure serum testosterone levels ... shaft specimen was taken for nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase ..... The rat as a model for the study of penile erection.

SIRT1 gene is associated with cardiovascular disease in the Iranian ...

African Journals Online (AJOL)

N. Mohtavinejad

2015-01-20

Jan 20, 2015 ... rs3758391 CC genotype in both additive and recessive models. The rs3758391 CC ... of the sirtuin family which belongs to the sirtuin family of nicotinamide adenine ..... of streptozotocin-induced diabetic rats. Genet Mol Res.

Genotypic and phenotypic spectrum of pyridoxine-dependent epilepsy (ALDH7A1 deficiency)

NARCIS (Netherlands)

Mills, P.B.; Footitt, E.J.; Mills, K.A.; Tuschl, K.; Aylett, S.; Varadkar, S.; Hemingway, C.; Marlow, N.; Rennie, J.; Baxter, P.; Dulac, O.; Nabbout, R.; Craigen, W.J.; Schmitt, B.; Feillet, F.; Christensen, E.; de Lonlay, P.; Pike, M.G.; Hughes, M.I.; Struijs, E.A.; Jakobs, C.; Zuberi, S.M.; Clayton, P.T.

2010-01-01

Pyridoxine-dependent epilepsy was recently shown to be due to mutations in the ALDH7A1 gene, which encodes antiquitin, an enzyme that catalyses the nicotinamide adenine dinucleotide-dependent dehydrogenation of l-α-aminoadipic semialdehyde/l-Δ

Binary and ternary cocrystals of sulfa drug acetazolamide with pyridine carboxamides and cyclic amides.

Science.gov (United States)

Bolla, Geetha; Nangia, Ashwini

2016-03-01

A novel design strategy for cocrystals of a sulfonamide drug with pyridine carboxamides and cyclic amides is developed based on synthon identification as well as size and shape match of coformers. Binary adducts of acetazolamide (ACZ) with lactams (valerolactam and caprolactam, VLM, CPR), cyclic amides (2-pyridone, labeled as 2HP and its derivatives MeHP, OMeHP) and pyridine amides (nicotinamide and picolinamide, NAM, PAM) were obtained by manual grinding, and their single crystals by solution crystallization. The heterosynthons in the binary cocrystals of ACZ with these coformers suggested a ternary combination for ACZ with pyridone and nicotinamide. Novel supramolecular synthons of ACZ with lactams and pyridine carboxamides are reported together with binary and ternary cocrystals for a sulfonamide drug. This crystal engineering study resulted in the first ternary cocrystal of acetazolamide with amide coformers, ACZ-NAM-2HP (1:1:1).

The Caenorhabditis elegans nicotinamidase PNC-1 enhances survival.

Science.gov (United States)

van der Horst, Armando; Schavemaker, Jolanda M; Pellis-van Berkel, Wendy; Burgering, Boudewijn M T

2007-04-01

In yeast, increasing the copy number of the nicotinamide adenine dinucleotide (NAD)-dependent deacetylase Sir2 extends lifespan, which can be inhibited by nicotinamide (Nam), the end-product of Sir2-mediated NAD-breakdown. Furthermore, the yeast pyrazinamidase/nicotinamidase PNC-1 can extend yeast lifespan by converting Nam. In Caenorhabditis elegans (C. elegans), increased dosage of the gene encoding SIR-2.1 also increases lifespan. Here, we report that knockdown of the C. elegans homologue of yeast PNC-1 as well as growing worms on Nam-containing medium significantly decreases adult lifespan. Accordingly, increased gene dosage of pnc-1 increases adult survival under conditions of oxidative stress. These data show for the first time the involvement of PNC-1/Nam in the survival of a multicellular organism and may also contribute to our understanding of lifespan regulation in mammals.

Leishmania infantum nicotinamidase is required for late-stage development in its natural sand fly vector, Phlebotomus perniciosus.

Science.gov (United States)

Gazanion, Elodie; Seblova, Veronika; Votypka, Jan; Vergnes, Baptiste; Garcia, Déborah; Volf, Petr; Sereno, Denis

2012-04-01

Leishmania infantum nicotinamidase, encoded by the Lipnc1 gene, converts nicotinamide into nicotinicacid to ensure Nicotinamide–Adenine–Dinucleotide (NAD+) biosynthesis. We were curious to explore the role of this enzyme during L. infantum development in its natural sand fly vector, Phlebotomus perniciosus (Diptera, Phlebotominae), using null mutants with a deleted Lipnc1 gene. The null mutants developed as well as the wild type L. infantum at the early time points post their ingestion within the bloodmeal. In contrast, once the blood meal digestion was completed, the null mutants were unable to develop further and establish late-stage infections. Data highlight the importance of the nicotinamide degradation pathway for Leishmania development in sand flies. They indicate that the endogenous nicotinamidase is essential for Leishmania development in the sand fly after the blood meal has been digested and the remnants defecated.

Intervening before the onset of Type 1 diabetes

DEFF Research Database (Denmark)

Reimers, Jesper Irving

2003-01-01

AIMS/HYPOTHESIS: To set up a clinical trial to establish whether nicotinamide can prevent or delay clinical onset of Type 1 diabetes. METHOD: The European Nicotinamide Diabetes Intervention Trial is a randomised, double-blind, placebo-controlled intervention trial undertaken in 18 European...... countries, Canada and the USA. Entry criteria were a first-degree family history of Type 1 diabetes, age 3-40 years, confirmed islet cell antibody (ICA) levels greater than or equal to 20 JDF units, and a non-diabetic OGTT; the study group was further characterised by intravenous glucose tolerance testing......) centile in 34%. Additional islet autoantibodies were identified in 354 trial entrants. Diabetes-associated HLA class II haplotypes were found in 84% of the younger age group and 80% of the older group. The protective haplotype HLA-DQA1*0102-DQB1*0602 was found in 10% overall. CONCLUSIONS...

Modeling of NAD+ analogues in horse liver alcohol dehydrogenase

NARCIS (Netherlands)

Beijer, N.A.; Buck, H.M.; Sluyterman, L.A.A.E.; Meijer, E.M.

1990-01-01

So far, the interactions of nicotinamide adenine dinucleotide (NAD+) derivatives with dehydrogenases are not very well understood. This hampers the introduction of NAD+ analogues with improved characteristics concerning industrial application. We have developed an AMBER molecular mechanics model in

Can we predict and/or prevent type I diabetes?

African Journals Online (AJOL)

1990-10-20

Oct 20, 1990 ... detecting 64KA using Western bloning with rat islet prepara- tions has been ... Although the model appears to give a good correlation, it must be .... DNA repair using cyrosolic nicotinamide adenine dinucleotide. (NAD) as a ...

Two X-linked chronic granulomatous disease patients with unusual NADPH oxidase properties

NARCIS (Netherlands)

Wolach, Baruch; Broides, Arnon; Zeeli, Tal; Gavrieli, Ronit; de Boer, Martin; van Leeuwen, Karin; Levy, Jacov; Roos, Dirk

2011-01-01

Chronic granulomatous disease (CGD) is an immune deficiency syndrome caused by defects in the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, the enzyme that generates reactive oxygen species (ROS) in phagocytizing leukocytes. This study evaluates the NADPH oxidase capacity in two

Kinetic and modelling studies of NAD+ and poly(ethylene glycol)-bound NAD+ in horse liver alcohol dehydrogenase

NARCIS (Netherlands)

Vanhommerig, S.A.M.; Sluyterman, L.A.A.E.; Meijer, E.M.

1996-01-01

Poly(ethylene glycol)-bound nicotinamide adenine dinucleotide (PEG-NAD+) has been successfully employed in the continuous production of L-amino acids from the corresponding alpha-keto acids by stereospecific reductive amination. Like many other dehydrogenases also horse liver alcohol dehydrogenase

A quick look at biochemistry : Carbohydrate metabolism

NARCIS (Netherlands)

Dashty, Monireh

2013-01-01

In mammals, there are different metabolic pathways in cells that break down fuel molecules to transfer their energy into high energy compounds such as adenosine-5'-triphosphate (ATP), guanosine-5'-triphosphate (GTP), reduced nicotinamide adenine dinucleotide (NADH2), reduced flavin adenine

South African Medical Journal - Vol 45, No 6 (1971)

African Journals Online (AJOL)

The clinical and biochemical effects of riboflavin and nicotinamide supplementation upon Bantu school children · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. W. Wittmann, J.P. Du Plessis, A. Nel, S.A. Fellingham ...

Nitric oxide synthase in the gill of Atlantic salmon: colocalization with and inhibition of Na+,K+-ATPase

DEFF Research Database (Denmark)

Ebbesson, Lars O E; Tipsmark, Christian K; Holmqvist, Bo

2005-01-01

We investigated the relationship between nitric oxide (NO) and Na(+),K(+)-ATPase (NKA) in the gill of anadromous Atlantic salmon. Cells containing NO-producing enzymes were revealed by means of nitric oxide synthase (NOS) immunocytochemistry and nicotinamide adenine dinucleotide phosphate diaphor...

Untitled

African Journals Online (AJOL)

11]. Isopropanol in the azeotrope was also estimated [16]. RESULTS AND DISCUSSION. On refluxing titanium (IV) isopropoxide with acetamide benzamide and nicotinamide in the molar ratio of 1:1,1:2,1:3 and 1:4 the mixed imido-alkoxy.

Mononucleotide precedes dinucleotide repeat instability during colorectal tumour development in Lynch syndrome patients

NARCIS (Netherlands)

Ferreira, Ana M.; Westers, Helga; Sousa, Sonia; Wu, Ying; Niessen, Renee C.; Olderode-Berends, Maran; van der Sluis, Tineke; Reuvekamp, Peter T. W.; Seruca, Raquel; Kleibeuker, Jan H.; Hollema, Harry; Sijmons, Rolf H.; Hofstra, Robert M. W.

A progressive accumulation of genetic alterations underlies the adenoma-carcinoma sequence of colorectal cancer. This accumulation of mutations is driven by genetic instability, of which there are different types. Microsatellite instability (MSI) is the predominant type present in the tumours of

Saccharomyces cerevisiae engineered for xylose metabolism requires gluconeogenesis and the oxidative branch of the pentose phosphate pathway for aerobic xylose assimilation

Science.gov (United States)

Saccharomyces strains engineered to ferment xylose using Scheffersomyces stipitis xylose reductase (XR) and xylitol dehydrogenase (XDH) genes appear to be limited by metabolic imbalances due to differing cofactor specificities of XR and XDH. The S. stipitis XR, which uses nicotinamide adenine dinucl...

Synthesis, characterization and antimicrobial activity of mixed ...

African Journals Online (AJOL)

Synthesis, characterization and antimicrobial activity of mixed ascorbic acid - nicotinamide metal complexes. ... The result of the antimicrobial studies showed that the mixed complexes have higher inhibitory activity than the original ligands against the tested bacteria and fungi species. KEY WORDS: Ascorbic acid, ...

139 - 142_lawal et al

African Journals Online (AJOL)

USER

ABSTRACT. The present study aimed at synthesizing copper(II) and zinc(II) complexes of mixed ascorbic acid and nicotinamide and physiochemically characterize by solubility test, melting point, conductivity test, infrared, electronic and proton nuclear magnetic resonance techniques. The result of the physiochemical ...

Gold electrodes modified with 16H, 18H-dibenzo[c,l]-7,9-dithia-16,18-diazapentacene for electrocatalytic oxidation of NADH

NARCIS (Netherlands)

Rosca, V.; Muresan, L.; Popescu, I.C.; Cristea, C.; Silberg, I.A.

2001-01-01

16H,18H-Dibenzo[c,l]-7,9-dithia-16,18-diazapentacene (DDDP), a new phenothiazine derivative containing two linearly condensed phenothiazine rings, strongly adsorbs on polyoriented gold resulting in a modified electrode with electrocatalytic activity for ß-nicotinamide adenine dinucleotide (NADH)

Central Core Disease Associated with Elevated Creatine ...

African Journals Online (AJOL)

was held in position by gum tragacanth. The sections were processed for nicotinamide-adenosine-diaphorase-tetra-. zoIium reductase, myofibrillar ATPase, phosphorylase, mitochondrial ATPase and routine haematoxylin and eosin, trichrome and PAS stains. The second muscle specimen was processed according to a ...

Deficiency of the Mitochondrial NAD Kinase Causes Stress-Induced Hepatic Steatosis in Mice

NARCIS (Netherlands)

Zhang, Kezhong; Kim, Hyunbae; Fu, Zhiyao; Qiu, Yining; Yang, Zhao; Wang, Jiemei; Zhang, Deqiang; Tong, Xin; Yin, Lei; Li, Jing; Wu, Jianmei; Qi, Nathan R.; Houten, Sander M.; Zhang, Ren

2018-01-01

The mitochondrial nicotinamide adenine dinucleotide (NAD) kinase (NADK2, also called MNADK) catalyzes phosphorylation of NAD to yield NADP. Little is known about the functions of mitochondrial NADP and MNADK in liver physiology and pathology. We investigated the effects of reduced mitochondrial NADP

Adipose tissue NAD+ biology in obesity and insulin resistance: From mechanism to therapy.

Science.gov (United States)

Yamaguchi, Shintaro; Yoshino, Jun

2017-05-01

Nicotinamide adenine dinucleotide (NAD + ) biosynthetic pathway, mediated by nicotinamide phosphoribosyltransferase (NAMPT), a key NAD + biosynthetic enzyme, plays a pivotal role in controlling many biological processes, such as metabolism, circadian rhythm, inflammation, and aging. Over the past decade, NAMPT-mediated NAD + biosynthesis, together with its key downstream mediator, namely the NAD + -dependent protein deacetylase SIRT1, has been demonstrated to regulate glucose and lipid metabolism in a tissue-dependent manner. These discoveries have provided novel mechanistic and therapeutic insights into obesity and its metabolic complications, such as insulin resistance, an important risk factor for developing type 2 diabetes and cardiovascular disease. This review will focus on the importance of adipose tissue NAMPT-mediated NAD + biosynthesis and SIRT1 in the pathophysiology of obesity and insulin resistance. We will also critically explore translational and clinical aspects of adipose tissue NAD + biology. © 2017 WILEY Periodicals, Inc.

Binary and ternary cocrystals of sulfa drug acetazolamide with pyridine carboxamides and cyclic amides

Directory of Open Access Journals (Sweden)

Geetha Bolla

2016-03-01

Full Text Available A novel design strategy for cocrystals of a sulfonamide drug with pyridine carboxamides and cyclic amides is developed based on synthon identification as well as size and shape match of coformers. Binary adducts of acetazolamide (ACZ with lactams (valerolactam and caprolactam, VLM, CPR, cyclic amides (2-pyridone, labeled as 2HP and its derivatives MeHP, OMeHP and pyridine amides (nicotinamide and picolinamide, NAM, PAM were obtained by manual grinding, and their single crystals by solution crystallization. The heterosynthons in the binary cocrystals of ACZ with these coformers suggested a ternary combination for ACZ with pyridone and nicotinamide. Novel supramolecular synthons of ACZ with lactams and pyridine carboxamides are reported together with binary and ternary cocrystals for a sulfonamide drug. This crystal engineering study resulted in the first ternary cocrystal of acetazolamide with amide coformers, ACZ–NAM–2HP (1:1:1.

Investigation of the Ionization Mechanism of NAD+/NADH-Modified Gold Electrodes in ToF-SIMS Analysis.

Science.gov (United States)

Hua, Xin; Zhao, Li-Jun; Long, Yi-Tao

2018-06-04

Analysis of nicotinamide adenine dinucleotide (NAD + /NADH)-modified electrodes is important for in vitro monitoring of key biological processes. In this work, time-of-flight secondary ion mass spectrometry (ToF-SIMS) was used to analyze NAD + /NADH-modified gold electrodes. Interestingly, no obvious characteristic peaks of nicotinamide fragment could be observed in the mass spectra of NAD + /NADH in their neutral sodium pyrophosphate form. However, after acidification, the characteristic peaks for both NAD + and NADH were detected. This was due to the suppression effect of inner pyrophosphoric salts in both neutral molecules. Besides, it was proved that the suppression by inner salt was intramolecular. No obvious suppression was found between neighboring molecules. These results demonstrated the suppression effect of inner salts in ToF-SIMS analysis, providing useful evidence for the study of ToF-SIMS ionization mechanism of organic molecule-modified electrodes. Graphical Abstract ᅟ.

Spectroscopic manifestation of trans- effect in tungsten (6) octahedral complexes

Energy Technology Data Exchange (ETDEWEB)

Buslaev, Yu A; Tsivadze, A Yu; Kharitonov, Yu Ya; Kokunov, Yu V; Gustyakova, M P [AN SSSR, Moscow. Inst. Obshchej i Neorganicheskoj Khimii

1977-10-01

The vibration spectra are studied of the following WOF/sub 4/ acetonitrile solutions in the presence of L ligands: formamide, acetamide, propioamide, butyric acid amide, dimethyl formamide, dimethyl acetamide, oxymethyl nicotinamide, diethyl nicotinamide, benzamide, salicylic acid amide, acetal acetamide, hydrorubean acid, hexamethyl phosphorus triamide, tetramethyl urea, TBP, DMSO and diethyl amine, molar ratio of WOF/sub 4/:L = 1:1. Infrared absorption spectra (400-4000 cm/sup -1/) and combination scattering spectra (50-4000 cm/sup -1/) were recorded. A decline in the vibration frequency ..nu..(WO) was caused by a lesser strength constant in the WO bond during exchange of CH/sub 3/CN for L. A slight weakening of the WO bond depending on the nature of the trans-ligands of L on the L-W-O coordinate is representative of the trans-effect of coordinated ligands in the octahedral complexes of tungsten, WOF/sub 4/xL.

Studying Catabolism of Protein ADP-Ribosylation.

Science.gov (United States)

Palazzo, Luca; James, Dominic I; Waddell, Ian D; Ahel, Ivan

2017-01-01

Protein ADP-ribosylation is a conserved posttranslational modification that regulates many major cellular functions, such as DNA repair, transcription, translation, signal transduction, stress response, cell division, aging, and cell death. Protein ADP-ribosyl transferases catalyze the transfer of an ADP-ribose (ADPr) group from the β-nicotinamide adenine dinucleotide (β-NAD + ) cofactor onto a specific target protein with the subsequent release of nicotinamide. ADP-ribosylation leads to changes in protein structure, function, stability, and localization, thus defining the appropriate cellular response. Signaling processes that are mediated by modifications need to be finely tuned and eventually silenced and one of the ways to achieve this is through the action of enzymes that remove (reverse) protein ADP-ribosylation in a timely fashion such as PARG, TARG1, MACROD1, and MACROD2. Here, we describe several basic methods used to study the enzymatic activity of de-ADP-ribosylating enzymes.

Hepatic NAD(+) deficiency as a therapeutic target for non-alcoholic fatty liver disease in ageing.

Science.gov (United States)

Zhou, Can-Can; Yang, Xi; Hua, Xia; Liu, Jian; Fan, Mao-Bing; Li, Guo-Qiang; Song, Jie; Xu, Tian-Ying; Li, Zhi-Yong; Guan, Yun-Feng; Wang, Pei; Miao, Chao-Yu

2016-08-01

Ageing is an important risk factor of non-alcoholic fatty liver disease (NAFLD). Here, we investigated whether the deficiency of nicotinamide adenine dinucleotide (NAD(+) ), a ubiquitous coenzyme, links ageing with NAFLD. Hepatic concentrations of NAD(+) , protein levels of nicotinamide phosphoribosyltransferase (NAMPT) and several other critical enzymes regulating NAD(+) biosynthesis, were compared in middle-aged and aged mice or patients. The influences of NAD(+) decline on the steatosis and steatohepatitis were evaluated in wild-type and H247A dominant-negative, enzymically-inactive NAMPT transgenic mice (DN-NAMPT) given normal or high-fat diet (HFD). Hepatic NAD(+) level decreased in aged mice and humans. NAMPT-controlled NAD(+) salvage, but not de novo biosynthesis pathway, was compromised in liver of elderly mice and humans. Given normal chow, middle-age DN-NAMPT mice displayed systemic NAD(+) reduction and had moderate NAFLD phenotypes, including lipid accumulation, enhanced oxidative stress, triggered inflammation and impaired insulin sensitivity in liver. All these NAFLD phenotypes, especially release of pro-inflammatory factors, Kupffer cell accumulation, monocytes infiltration, NLRP3 inflammasome pathway and hepatic fibrosis (Masson's staining and α-SMA staining), deteriorated further under HFD challenge. Oral administration of nicotinamide riboside, a natural NAD(+) precursor, completely corrected these NAFLD phenotypes induced by NAD(+) deficiency alone or HFD, whereas adenovirus-mediated SIRT1 overexpression only partially rescued these phenotypes. These results provide the first evidence that ageing-associated NAD(+) deficiency is a critical risk factor for NAFLD, and suggest that supplementation with NAD(+) substrates may be a promising therapeutic strategy to prevent and treat NAFLD. © 2016 The British Pharmacological Society.

4-Pyridone-3-carboxamide-1-β-d-ribonucleoside Triphosphate (4PyTP, a Novel NAD+ Metabolite Accumulating in Erythrocytes of Uremic Children: A Biomarker for a Toxic NAD+ Analogue in Other Tissues?

Directory of Open Access Journals (Sweden)

Elizabeth A. Carrey

2011-06-01

Full Text Available We have identified a novel nucleotide, 4-pyridone 3/5-carboxamide ribonucleoside triphosphate (4PyTP, which accumulates in human erythrocytes during renal failure. Using plasma and erythrocyte extracts obtained from children with chronic renal failure we show that the concentration of 4PyTP is increased, as well as other soluble NAD+ metabolites (nicotinamide, N1-methylnicotinamide and 4Py-riboside and the major nicotinamide metabolite N1-methyl-2-pyridone-5-carboxamide (2PY, with increasing degrees of renal failure. We noted that 2PY concentration was highest in the plasma of haemodialysis patients, while 4PyTP was highest in erythrocytes of children undergoing peritoneal dialysis: its concentration correlated closely with 4Py-riboside, an authentic precursor of 4PyTP, in the plasma. In the dialysis patients, GTP concentration was elevated: similar accumulation was noted previously, as a paradoxical effect in erythrocytes during treatment with immunosuppressants such as ribavirin and mycophenolate mofetil, which deplete GTP through inhibition of IMP dehydrogenase in nucleated cells such as lymphocytes. We predict that 4Py-riboside and 4Py-nucleotides bind to this enzyme and alter its activity. The enzymes that regenerate NAD+ from nicotinamide riboside also convert the drugs tiazofurin and benzamide riboside into NAD+ analogues that inhibit IMP dehydrogenase more effectively than the related ribosides: we therefore propose that the accumulation of 4PyTP in erythrocytes during renal failure is a marker for the accumulation of a related toxic NAD+ analogue that inhibits IMP dehydrogenase in other cells.

Uptake and Metabolism of Antibiotics Roseoflavin and 8-Demethyl-8-Aminoriboflavin in Riboflavin-Auxotrophic Listeria monocytogenes.

Science.gov (United States)

Matern, Andreas; Pedrolli, Danielle; Großhennig, Stephanie; Johansson, Jörgen; Mack, Matthias

2016-12-01

The riboflavin analogs roseoflavin (RoF) and 8-demethyl-8-aminoriboflavin (AF) are produced by the bacteria Streptomyces davawensis and Streptomyces cinnabarinus Riboflavin analogs have the potential to be used as broad-spectrum antibiotics, and we therefore studied the metabolism of riboflavin (vitamin B 2 ), RoF, and AF in the human pathogen Listeria monocytogenes, a bacterium which is a riboflavin auxotroph. We show that the L. monocytogenes protein Lmo1945 is responsible for the uptake of riboflavin, RoF, and AF. Following import, these flavins are phosphorylated/adenylylated by the bifunctional flavokinase/flavin adenine dinucleotide (FAD) synthetase Lmo1329 and adenylylated by the unique FAD synthetase Lmo0728, the first monofunctional FAD synthetase to be described in bacteria. Lmo1329 generates the cofactors flavin mononucleotide (FMN) and FAD, whereas Lmo0728 produces FAD only. The combined activities of Lmo1329 and Lmo0728 are responsible for the intracellular formation of the toxic cofactor analogs roseoflavin mononucleotide (RoFMN), roseoflavin adenine dinucleotide (RoFAD), 8-demethyl-8-aminoriboflavin mononucleotide (AFMN), and 8-demethyl-8-aminoriboflavin adenine dinucleotide (AFAD). In vivo reporter gene assays and in vitro transcription/translation experiments show that the L. monocytogenes FMN riboswitch Rli96, which controls expression of the riboflavin transport gene lmo1945, is negatively affected by riboflavin/FMN and RoF/RoFMN but not by AF/AFMN. Treatment of L. monocytogenes with RoF or AF leads to drastically reduced FMN/FAD levels. We suggest that the reduced flavin cofactor levels in combination with concomitant synthesis of inactive cofactor analogs (RoFMN, RoFAD, AFMN, and AFAD) explain why RoF and AF contribute to antibiotic activity in L. monocytogenes IMPORTANCE: The riboflavin analogs roseoflavin (RoF) and 8-demethyl-8-aminoriboflavin (AF) are small molecules which are produced by Streptomyces davawensis and Streptomyces cinnabarinus

Genotypic and phenotypic spectrum of pyridoxine-dependent epilepsy (ALDH7A1 deficiency)

DEFF Research Database (Denmark)

Mills, Philippa B; Footitt, Emma J; Mills, Kevin A

2010-01-01

Pyridoxine-dependent epilepsy was recently shown to be due to mutations in the ALDH7A1 gene, which encodes antiquitin, an enzyme that catalyses the nicotinamide adenine dinucleotide-dependent dehydrogenation of l-alpha-aminoadipic semialdehyde/L-Delta1-piperideine 6-carboxylate. However, whilst t...

Chronic granulomatous disease caused by mutations other than the common GT deletion in NCF1, the gene encoding the p47phox component of the phagocyte NADPH oxidase

NARCIS (Netherlands)

Roos, Dirk; de Boer, Martin; Köker, M. Yavuz; Dekker, Jan; Singh-Gupta, Vinita; Ahlin, Anders; Palmblad, Jan; Sanal, Ozden; Kurenko-Deptuch, Magdalena; Jolles, Stephen; Wolach, Baruch

2006-01-01

Chronic granulomatous disease (CGD) is an inherited immunodeficiency caused by defects in any of four genes encoding components of the leukocyte nicotinamide dinucleotide phosphate, reduced (NADPH) oxidase. One of these is the autosomal neutrophil cytosolic factor 1 (NCF1) gene encoding the p47phox

Application of NAD(P)H oxidase for cofactor regeneration in dehydrogenase catalyzed oxidations

DEFF Research Database (Denmark)

Rehn, Gustav; Pedersen, Asbjørn Toftgaard; Woodley, John

2016-01-01

alcohol dehydrogenases. However, their effective use requires an effective regeneration of the oxidized nicotinamide cofactor (NAD(P)+), which is critical for the economic feasibility of the process. NAD(P)H oxidase is an enzyme class of particular interest for this cofactor regeneration since it enables...

NAD(+) metabolism: A therapeutic target for age-related metabolic disease

NARCIS (Netherlands)

Mouchiroud, Laurent; Houtkooper, Riekelt H.; Auwerx, Johan

2013-01-01

Abstract Nicotinamide adenine dinucleotide (NAD) is a central metabolic cofactor by virtue of its redox capacity, and as such regulates a wealth of metabolic transformations. However, the identification of the longevity protein silent regulator 2 (Sir2), the founding member of the sirtuin protein

Journal of Biosciences | Indian Academy of Sciences

Indian Academy of Sciences (India)

Given the potential application of xylose reductase enzymes that preferentially utilize the reduced form of nicotinamide adenine dinucleotide (NADH) rather than NADPH in the fermentation of five carbon sugars by genetically engineered microorganisms, the coenzyme selectivity of TeXR was altered by site-directed ...

Multicomponent ternary cocrystals of the sulfonamide group with pyridine-amides and lactams.

Science.gov (United States)

Bolla, Geetha; Nangia, Ashwini

2015-11-04

SMBA was selected as a bifunctional sulfa drug to design ternary cocrystals with pyridine amides and lactam coformers. Supramolecular assembly of five ternary cocrystals of p-sulfonamide benzoic acid with nicotinamide and 2-pyridone is demonstrated and reproducible heterosynthons are identified for crystal engineering.

Kongenit methaemoglobinaemi: en sjaelden årsag til neonatal cyanose

DEFF Research Database (Denmark)

Smith, Birgitte; Pryds, Ole Axel; Christensen, Ernst

2008-01-01

We present a case study of a newborn girl with a reduced erythrocytic nicotinamide adenine dinucleotide (NADH)-dependent methaemoglobin reductase level. Within the first days of life she developed cyanosis due to a methaemoglobin level of 21%. The hyperoxia test was characteristic, with normal in...

Directed Evolution of Membrane Transport Using Synthetic Selections

DEFF Research Database (Denmark)

Bali, Anne Pihl; Genee, Hans J.; Sommer, Morten O. A.

2018-01-01

systems that enable selective growth of E. coli cells only if they functionally express an importer that is specific to the biosensor ligand. Using this system in a directed evolution framework, we successfully engineer the specificity of nicotinamide riboside transporters, PnuC, to accept thiamine...

Magnetism, structure and chemical order in small CoPd clusters: A first-principles study

KAUST Repository

Mokkath, Junais Habeeb

2014-01-01

The structural, electronic and magnetic properties of small ComPdn (N=m+n=8,m=0-N) nanoalloy clusters are studied in the framework of a generalized-gradient approximation to density-functional theory. The optimized cluster structures have a clear tendency to maximize the number of nearest-neighbor CoCo pairs. The magnetic order is found to be ferromagnetic-like (FM) for all the ground-state structures. Antiferromagnetic-like spin arrangements were found in some low-lying isomers. The average magnetic moment per atom μ̄N increases approximately linearly with Co content. A remarkable enhancement of the local Co moments is observed as a result of Pd doping. This is a consequence of the increase in the number of Co d holes, due to CoPd charge transfer, combined with the reduced local coordination. The influence of spin-orbit interactions on the cluster properties is also discussed. © 2013 Elsevier B.V.

Gene cloning and characterization of NADH oxidase from ...

African Journals Online (AJOL)

The genome search of Thermococcus kodakarensis revealed three open reading frames, Tk0304, Tk1299 and Tk1392 annotated as nicotinamide adenine dinucleotide (NADH) oxidases. This study deals with cloning, and characterization of Tk0304. The gene, composed of 1320 nucleotides, encodes a protein of 439 ...

Multiple origins of European populations of the giant liver fluke Fascioloides magna (Trematoda: Fasciolidae), a liver parasite of ruminants

Czech Academy of Sciences Publication Activity Database

Kraľová-Hromadová, I.; Bazsalovicsová, E.; Štefka, Jan; Špakulová, M.; Vávrová, S.; Szemes, T.; Tkach, V.; Trudgett, A.; Pybus, M.

2011-01-01

Roč. 41, 3/4 (2011), 373-383 ISSN 0020-7519 Institutional research plan: CEZ:AV0Z60220518 Keywords : Biogeography * Alien species * Introduced parasite * Mitochondrial DNA * Cytochrome c oxidase * Nicotinamide dehydrogenase Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 3.393, year: 2011

Genetic interrelationships of North American populations of giant liver fluke Fascioloides magna

Czech Academy of Sciences Publication Activity Database

Bazsalovicsová, E.; Kráľová-Hromadová, I.; Štefka, Jan; Minárik, G.; Bokorová, S.; Pybus, M.

2015-01-01

Roč. 8, MAY 28 2015 (2015), s. 288 ISSN 1756-3305 EU Projects: European Commission(XE) 316304 Institutional support: RVO:60077344 Keywords : Trematoda * Fasciolidae * Mitochondrial DNA * Cytochrome c oxidase * Nicotinamide dehydrogenase * Spatial distribution Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.234, year: 2015

Dermatitis herpetiformis intolerant to dapsone in Aids

Directory of Open Access Journals (Sweden)

Krishna K

1999-01-01

Full Text Available A 35-year-old man with AIDS and pulmonary tuberculosis presented with lesions suggestive of dermatitis herpetiformis and intolerance to dapsone. He was managed successfully with a combination of nicotinamide 200 mg/day and indomethacin 75 mg/day, topical steroids and gluten free diet.

Crystal structure of the vitamin B3 transporter PnuC, a full-length SWEET homolog

NARCIS (Netherlands)

Jähme, Michael; Guskov, Albert; Slotboom, Dirk Jan

2014-01-01

PnuC transporters catalyze cellular uptake of the NAD(+) precursor nicotinamide riboside (NR) and belong to a large superfamily that includes the SWEET sugar transporters. We present a crystal structure of Neisseria mucosa PnuC, which adopts a highly symmetrical fold with 3 + 1 + 3 membrane topology

Thermal behaviour of zinc(II) 5-chlorosalicylate complex compounds

Czech Academy of Sciences Publication Activity Database

Györyová, K.; Chomič, J.; Kovářová, Jana

2005-01-01

Roč. 80, č. 2 (2005), s. 375-380 ISSN 1388-6150 Grant - others:Slovak Ministry of Education(SK) VEGA 1/2474/05 Institutional research plan: CEZ:AV0Z40500505 Keywords : caffeine * chlorosalicylate complexes * nicotinamide Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.425, year: 2005

pH-tuneable binding of 2′-phospho-ADP-ribose to ketopantoate reductase: a structural and calorimetric study

Energy Technology Data Exchange (ETDEWEB)

Ciulli, Alessio [University Chemical Laboratory, Lensfield Road, Cambridge CB2 1EW (United Kingdom); Lobley, Carina M. C. [Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA (United Kingdom); Tuck, Kellie L. [University Chemical Laboratory, Lensfield Road, Cambridge CB2 1EW (United Kingdom); Smith, Alison G. [Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA (United Kingdom); Blundell, Tom L. [Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge CB2 1GA (United Kingdom); Abell, Chris, E-mail: ca26@cam.ac.uk [University Chemical Laboratory, Lensfield Road, Cambridge CB2 1EW (United Kingdom)

2007-02-01

A combined crystallographic, calorimetric and mutagenic study has been used to show how changes in pH give rise to two distinct binding modes of 2′-phospho-ADP-ribose to ketopantoate reductase. The crystal structure of Escherichia coli ketopantoate reductase in complex with 2′-monophosphoadenosine 5′-diphosphoribose, a fragment of NADP{sup +} that lacks the nicotinamide ring, is reported. The ligand is bound at the enzyme active site in the opposite orientation to that observed for NADP{sup +}, with the adenine ring occupying the lipophilic nicotinamide pocket. Isothermal titration calorimetry with R31A and N98A mutants of the enzyme is used to show that the unusual ‘reversed binding mode’ observed in the crystal is triggered by changes in the protonation of binding groups at low pH. This research has important implications for fragment-based approaches to drug design, namely that the crystallization conditions and the chemical modification of ligands can have unexpected effects on the binding modes.

Effects of B Vitamins Overload on Plasma Insulin Level and Hydrogen Peroxide Generation in Rats.

Science.gov (United States)

Sun, Wuping; Zhai, Mingzhu; Zhou, Qian; Qian, Chengrui; Jiang, Changyu

2017-08-31

It has been reported that nicotinamide-overload induces oxidative stress associated with insulin resistance, the key feature of type 2 diabetes mellitus (T2DM). This study aimed to investigate the effects of B vitamins in T2DM. Glucose tolerance tests were carried out in adult Sprague-Dawley rats treated with or without cumulative doses of B vitamins. More specifically, insulin tolerance tests were also carried out in adult Sprague-Dawley rats treated with or without cumulative doses of Vitamin B3. We found that cumulative Vitamin B1 and Vitamin B3 administration significantly increased the plasma H₂O₂ levels associated with high insulin levels. Only Vitamin B3 reduced muscular and hepatic glycogen contents. Cumulative administration of nicotinic acid, another form of Vitamin B3, also significantly increased plasma insulin level and H₂O₂ generation. Moreover, cumulative administration of nicotinic acid or nicotinamide impaired glucose metabolism. This study suggested that excess Vitamin B1 and Vitamin B3 caused oxidative stress and insulin resistance.

Inhibitors of poly (ADP-ribose) polymerase and their enhancement of alkylating agent cytotoxicity in vivo

International Nuclear Information System (INIS)

Horsman, M.R.; Brown, D.M.; Hirst, D.G.; Brown, J.M.

1984-01-01

The chromosomal enzyme poly (ADP-ribose) polymerase (ADPRP) is involved in the repair of DNA damage caused by both ionizing radiation and alkylating agents. The authors have shown that certain inhibitors of this enzyme decrease potentially lethal damage repair after X-rays. The aim of the present study was to investigate the possible enhancement of alkylating agent damage in vivo by several of these ADPRP inhibitors. 3-aminobenzamide (200 mg/kg), caffeine (200 mg/kg), or nicotinamide (1000 mg/kg) given to RIF-1-tumor-bearing mice immediately before a dose of melphalan (L-PAM) (8 mg/kg) produced enhancement of tumor response as demonstrated by an in vivo in vitro tumor excision assay. Caffeine and nicotinamide provided the greatest enhancement of L-PAM cytotoxicity with at least a 100-fold increase in killing. Data are presented on the mechanism by which these drugs and other more potent inhibitors enhance the tumor cell killing by L-PAM and other alkylating agents

Improved Ethanol Production from Xylose by Candida shehatae Induced by Dielectric Barrier Discharge Air Plasma

International Nuclear Information System (INIS)

Chen Huixia; Xiu Zhilong; Bai Fengwu

2014-01-01

Xylose fermentation is essential for ethanol production from lignocellulosic biomass. Exposure of the xylose-fermenting yeast Candida shehatae (C. shehatae) CICC1766 to atmospheric pressure dielectric barrier discharge (DBD) air plasma yields a clone (designated as C81015) with stability, which exhibits a higher ethanol fermentation rate from xylose, giving a maximal enhancement in ethanol production of 36.2% compared to the control (untreated). However, the biomass production of C81015 is lower than that of the control. Analysis of the NADH (nicotinamide adenine dinucleotide)- and NADPH (nicotinamide adenine dinucleotide phosphate)-linked xylose reductases and NAD + -linked xylitol dehydrogenase indicates that their activities are enhanced by 34.1%, 61.5% and 66.3%, respectively, suggesting that the activities of these three enzymes are responsible for improving ethanol fermentation in C81015 with xylose as a substrate. The results of this study show that DBD air plasma could serve as a novel and effective means of generating microbial strains that can better use xylose for ethanol fermentation

The in vitro screening of aromatic amides as potential inhibitors of poly (ADP-ribose) polymerase

International Nuclear Information System (INIS)

Brown, D.M.; Horsman, M.R.; Lee, W.W.; Brown, J.M.

1984-01-01

It is now well established that the chromosomal enzyme poly (ADP-ribose) polymerase (ADPRP) is involved in the repair of DNA damage caused by ionizing radiation and alkylating agents, although the mechanisms involved are still not clear. ADPRP inhibitors include thymidine, nicotinamides, benzamides and methyl xanthines. The authors have demonstrated that these compounds are effective inhibitors of X-ray-induced potentially lethal damage repair (PLDR). More recently, they have shown that the cytotoxicity of the bifunctional alkylating L-phenylalanine mustard (L-PAM) was enhanced in vitro and in vivo by 3-aminobenzamide, nicotinamide and caffeine, although in the latter case pharmacokinetic changes could have contributed to the enhanced killing. The authors have examined a series of substituted carbocyclic and heterocyclic aromatic amides as potential inhibitors of ADPRP. The effect of these compounds on ADPRP activity in vitro as well as their effect on the repair of X-ray and alkylation damage in vitro are presented

The human NAD metabolome: Functions, metabolism and compartmentalization

Science.gov (United States)

Nikiforov, Andrey; Kulikova, Veronika; Ziegler, Mathias

2015-01-01

Abstract The metabolism of NAD has emerged as a key regulator of cellular and organismal homeostasis. Being a major component of both bioenergetic and signaling pathways, the molecule is ideally suited to regulate metabolism and major cellular events. In humans, NAD is synthesized from vitamin B3 precursors, most prominently from nicotinamide, which is the degradation product of all NAD-dependent signaling reactions. The scope of NAD-mediated regulatory processes is wide including enzyme regulation, control of gene expression and health span, DNA repair, cell cycle regulation and calcium signaling. In these processes, nicotinamide is cleaved from NAD+ and the remaining ADP-ribosyl moiety used to modify proteins (deacetylation by sirtuins or ADP-ribosylation) or to generate calcium-mobilizing agents such as cyclic ADP-ribose. This review will also emphasize the role of the intermediates in the NAD metabolome, their intra- and extra-cellular conversions and potential contributions to subcellular compartmentalization of NAD pools. PMID:25837229

Regulation of hydrogen production by Enterobacter aerogenes by external NADH and NAD{sup +}

Energy Technology Data Exchange (ETDEWEB)

Zhang, Chong; Ma, Kun; Xing, Xin-Hui [Department of Chemical Engineering, Tsinghua University, Beijing 100084 (China)

2009-02-15

Experiments involving the addition of external nicotinamide adenine dinucleotide, reduced form (NADH) or nicotinamide adenine dinucleotide (NAD{sup +}) have been designed to examine how the hydrogen in Enterobacter aerogenes is liberated by NADH or NAD{sup +}. The addition of external NADH or NAD{sup +} was found to regulate hydrogen production by E. aerogenes in resting cells, batch cultures, and chemostat cultures. Particularly in chemostat cultivation, with the external addition of NADH, hydrogen production via the NADH pathway was decreased, while that via the formate pathway was increased; in the end, the overall hydrogen p was decreased. The addition of NAD{sup +}, on the other hand, gave the opposite results. The membrane-bound hydrogenase was found to play a central role in regulating hydrogen production. The occurrence of NADH oxidation (NAD{sup +} reduction) on the cell membrane resulted in an electron flow across the membrane; this changed the oxidation state and metabolic pattern of the cells, which eventually affected the hydrogen evolution. (author)

pH-tuneable binding of 2′-phospho-ADP-ribose to ketopantoate reductase: a structural and calorimetric study

International Nuclear Information System (INIS)

Ciulli, Alessio; Lobley, Carina M. C.; Tuck, Kellie L.; Smith, Alison G.; Blundell, Tom L.; Abell, Chris

2007-01-01

A combined crystallographic, calorimetric and mutagenic study has been used to show how changes in pH give rise to two distinct binding modes of 2′-phospho-ADP-ribose to ketopantoate reductase. The crystal structure of Escherichia coli ketopantoate reductase in complex with 2′-monophosphoadenosine 5′-diphosphoribose, a fragment of NADP + that lacks the nicotinamide ring, is reported. The ligand is bound at the enzyme active site in the opposite orientation to that observed for NADP + , with the adenine ring occupying the lipophilic nicotinamide pocket. Isothermal titration calorimetry with R31A and N98A mutants of the enzyme is used to show that the unusual ‘reversed binding mode’ observed in the crystal is triggered by changes in the protonation of binding groups at low pH. This research has important implications for fragment-based approaches to drug design, namely that the crystallization conditions and the chemical modification of ligands can have unexpected effects on the binding modes

Cloning, expression and characterization of alcohol dehydrogenases in the silkworm Bombyx mori

Directory of Open Access Journals (Sweden)

Nan Wang

2011-01-01

Full Text Available Alcohol dehydrogenases (ADH are a class of enzymes that catalyze the reversible oxidation of alcohols to corresponding aldehydes or ketones, by using either nicotinamide adenine dinucleotide (NAD or nicotinamide adenine dinucleotide phosphate (NADP, as coenzymes. In this study, a short-chain ADH gene was identified in Bombyx mori by 5'-RACE PCR. This is the first time the coding region of BmADH has been cloned, expressed, purified and then characterized. The cDNA fragment encoding the BmADH protein was amplified from a pool of silkworm cDNAs by PCR, and then cloned into E. coli expression vector pET-30a(+. The recombinant His-tagged BmADH protein was expressed in E. coli BL21 (DE3, and then purified by metal chelating affinity chromatography. The soluble recombinant BmADH, produced at low-growth temperature, was instrumental in catalyzing the ethanol-dependent reduction of NAD+, thereby indicating ethanol as one of the substrates of BmADH.

Improved Ethanol Production from Xylose by Candida shehatae Induced by Dielectric Barrier Discharge Air Plasma

Science.gov (United States)

Chen, Huixia; Xiu, Zhilong; Bai, Fengwu

2014-06-01

Xylose fermentation is essential for ethanol production from lignocellulosic biomass. Exposure of the xylose-fermenting yeast Candida shehatae (C. shehatae) CICC1766 to atmospheric pressure dielectric barrier discharge (DBD) air plasma yields a clone (designated as C81015) with stability, which exhibits a higher ethanol fermentation rate from xylose, giving a maximal enhancement in ethanol production of 36.2% compared to the control (untreated). However, the biomass production of C81015 is lower than that of the control. Analysis of the NADH (nicotinamide adenine dinucleotide)- and NADPH (nicotinamide adenine dinucleotide phosphate)-linked xylose reductases and NAD+-linked xylitol dehydrogenase indicates that their activities are enhanced by 34.1%, 61.5% and 66.3%, respectively, suggesting that the activities of these three enzymes are responsible for improving ethanol fermentation in C81015 with xylose as a substrate. The results of this study show that DBD air plasma could serve as a novel and effective means of generating microbial strains that can better use xylose for ethanol fermentation.

Biochemical reasoning for radiation protection and screening methods for radiation sensitivity and potential carcinogenicity

International Nuclear Information System (INIS)

Riklis, Emanuel; Emerit, Ingrid

1994-01-01

Cells of different genetic characteristics respond differently to agents that modify radiation effects. When the modification is a result of chemical repair, reduction of the amount of damage by radical scavenging, production of hypoxia, or any other such mechanism, then the modification of the response will be the same for all types of cells, but not the same when biological or biochemical parameters are involved, because the differences between the cells affect the final outcome, and the genetic traits obviously become affected by chemical modifying agents. Some of these agents directly affect the repair of deoxyribonucleic acid (DNA) by mechanisms not yet understood. Another agent nicotinamide (NA), is directly linked to a repair pathway. Thus, a system that uses NA as a precursor of nicotinamide adenine dinucleotide (NAD) + , and uses NAD + to produce the polymer polyadenosine diphosphate ribose (PADPR) appears to be an interesting and important factor in the biochemical events that may be linked to improved radioprotection. (author). 36 refs., 5 figs

Kynurenine Pathway Metabolism is Involved in the Maintenance of the Intracellular NAD Concentration in Human Primary Astrocytes

Directory of Open Access Journals (Sweden)

Ross Grant

2010-01-01

Full Text Available Efficient synthesis of NAD + is critical to maintaining cell viability in all organs of the body. However, little is known of the pathway(s by which cells of the central nervous system produce NAD + . The aim of this study was to investigate the relationship, between tryptophan degradation via the kynurenine pathway (KP and de novo NAD + synthesis in human astrocytes, a major cell type within the brain. In this study we observed that inhibition of single enzymes of the KP resulted in significant decreases in NAD + levels in astroglial cells after a 24 hr period. We also observed that astrocytes cultured in media deficient in tryptophan, nicotinic acid and nicotinamide resulted in a 50% decrease in NAD + levels after 24 hrs. This decrease in NAD + was partially restored by supplementation of the culture media with either tryptophan or kynurenine, or nicotinic acid or with supply of the salvage pathway precursor nicotinamide.

Kynurenine Pathway Metabolism is Involved in the Maintenance of the Intracellular NAD+ Concentration in Human Primary Astrocytes

Science.gov (United States)

Grant, Ross; Nguyen, Susan; Guillemin, Gilles

2010-01-01

Efficient synthesis of NAD+ is critical to maintaining cell viability in all organs of the body. However, little is known of the pathway(s) by which cells of the central nervous system produce NAD+. The aim of this study was to investigate the relationship, between tryptophan degradation via the kynurenine pathway (KP) and de novo NAD+ synthesis in human astrocytes, a major cell type within the brain. In this study we observed that inhibition of single enzymes of the KP resulted in significant decreases in NAD+ levels in astroglial cells after a 24 hr period. We also observed that astrocytes cultured in media deficient in tryptophan, nicotinic acid and nicotinamide resulted in a 50% decrease in NAD+ levels after 24 hrs. This decrease in NAD+ was partially restored by supplementation of the culture media with either tryptophan or kynurenine, or nicotinic acid or with supply of the salvage pathway precursor nicotinamide. PMID:22084595

NADH:ubiquinone reductase and succinate dehydrogenase activity in the liver of rats with acetaminophen-induced toxic hepatitis on the background of alimentary protein deficiency

Directory of Open Access Journals (Sweden)

G. P. Kopylchuk

2015-02-01

Full Text Available The ratio between the redox forms of the nicotinamide coenzymes and key enzymatic activity of the I and II respiratory chain complexes in the liver cells mitochondria of rats with acetaminophen-induced hepatitis under the conditions of alimentary deprivation of protein was studied. It was estimated, that under the conditions of acute acetaminophen-induced hepatitis of rats kept on a low-protein diet during 4 weeks a significant decrease of the NADH:ubiquinone reductase and succinate dehydrogenase activity with simultaneous increase of the ratio between redox forms of the nicotinamide coenzymes (NAD+/NADН is observed compared to the same indices in the liver cells of animals with experimental hepatitis kept on the ration balanced by all nutrients. Results of research may become basic ones for the biochemical rationale for the approaches directed to the correction and elimination of the consequences­ of energy exchange in the toxic hepatitis, induced on the background of protein deficiency.

Discovery of potential visfatin activators using in silico docking and ADME predictions as therapy for type 2 diabetes

Directory of Open Access Journals (Sweden)

Olusola Olalekan Elekofehinti

2018-06-01

Full Text Available Visfatin (Nicotinamide phosphoribosyltransferase is an adipokine implicated in mediating insulin resistance and exhibiting insulin mimetic effect and therefore represents a druggable target for diabetes therapy. About 3,844 peroxisome proliferator activated receptor gamma (PPARγ agonists documented in Chembl database were docked with PPARγ and those with binding energy of >−9 kcal/mol having experimental EC50 of 0.1 to 1 nM were selected. The candidate compounds (27 were thereafter docked with visfatin (PDB ID: 4WQ6 using AutodockVina out of which eight compounds that ranked highest in binding energy (when compared with the co-crystallized ligand of visfatin: 3TQ were selected. Compound 25 exhibited favorable ligand-protein molecular interaction and respected Lipinski’s rule of five and interestingly from the absorption, distribution, metabolism and excretion (ADME-Toxicity analysis the compound have enhanced pharmacological properties than the current ligand of visfatin. Keywords: Nicotinamide phosphoribosyltransferase, Visfatin molecular docking, Type 2 diabetes, Adipokines

A General Tool for Engineering the NAD/NADP Cofactor Preference of Oxidoreductases.

Science.gov (United States)

Cahn, Jackson K B; Werlang, Caroline A; Baumschlager, Armin; Brinkmann-Chen, Sabine; Mayo, Stephen L; Arnold, Frances H

2017-02-17

The ability to control enzymatic nicotinamide cofactor utilization is critical for engineering efficient metabolic pathways. However, the complex interactions that determine cofactor-binding preference render this engineering particularly challenging. Physics-based models have been insufficiently accurate and blind directed evolution methods too inefficient to be widely adopted. Building on a comprehensive survey of previous studies and our own prior engineering successes, we present a structure-guided, semirational strategy for reversing enzymatic nicotinamide cofactor specificity. This heuristic-based approach leverages the diversity and sensitivity of catalytically productive cofactor binding geometries to limit the problem to an experimentally tractable scale. We demonstrate the efficacy of this strategy by inverting the cofactor specificity of four structurally diverse NADP-dependent enzymes: glyoxylate reductase, cinnamyl alcohol dehydrogenase, xylose reductase, and iron-containing alcohol dehydrogenase. The analytical components of this approach have been fully automated and are available in the form of an easy-to-use web tool: Cofactor Specificity Reversal-Structural Analysis and Library Design (CSR-SALAD).

Enhancing NAD+ salvage metabolism is neuroprotective in a PINK1 model of Parkinson's disease

Directory of Open Access Journals (Sweden)

Susann Lehmann

2017-02-01

Full Text Available Familial forms of Parkinson's disease (PD caused by mutations in PINK1 are linked to mitochondrial impairment. Defective mitochondria are also found in Drosophila models of PD with pink1 mutations. The co-enzyme nicotinamide adenine dinucleotide (NAD+ is essential for both generating energy in mitochondria and nuclear DNA repair through NAD+-consuming poly(ADP-ribose polymerases (PARPs. We found alterations in NAD+ salvage metabolism in Drosophila pink1 mutants and showed that a diet supplemented with the NAD+ precursor nicotinamide rescued mitochondrial defects and protected neurons from degeneration. Additionally, a mutation of Parp improved mitochondrial function and was neuroprotective in the pink1 mutants. We conclude that enhancing the availability of NAD+ by either the use of a diet supplemented with NAD+ precursors or the inhibition of NAD+-dependent enzymes, such as PARPs, which compete with mitochondria for NAD+, is a viable approach to preventing neurotoxicity associated with mitochondrial defects.

Antioxidant and Hypoglycaemic Effects of Ardisia Compressa (HBEK ...

African Journals Online (AJOL)

Purpose: To evaluate the possible hypoglycaemic, hypolipidemic, and antioxidant activities of Ardisia compressa (AC) on a rat model of type 2 diabetes. Methods: Diabetes was induced in female Wistar rats by intraperitoneal (i.p.) administration of streptozotocin (65 mg/kg) and nicotinamide (120 mg/kg). The diabetic ...

Application of continuous stirred membrane reactor to 3-cyanopyridine bioconversion using the nitrile hydratase–amidase cascade system of Microbacterium imperiale CBS 498-74

Czech Academy of Sciences Publication Activity Database

Cantarella, L.; Gallifuoco, A.; Malandra, A.; Martínková, Ludmila; Pasquarelli, F.; Spera, A.; Cantarella, M.

2010-01-01

Roč. 47, č. 3 (2010), s. 64-70 ISSN 0141-0229 R&D Projects: GA MŠk OC09046 Institutional research plan: CEZ:AV0Z50200510 Keywords : Nitrile hydratase-amidase cascade system * 3-Cyanopyridine bioconversion * Nicotinamide Subject RIV: EE - Microbiology, Virology Impact factor: 2.287, year: 2010

Clinical, functional, and genetic characterization of chronic granulomatous disease in 89 Turkish patients

NARCIS (Netherlands)

Köker, Mustafa Yavuz; Camcıoğlu, Yıldız; van Leeuwen, Karin; Kılıç, Sara Şebnem; Barlan, Işıl; Yılmaz, Mustafa; Metin, Ayşe; de Boer, Martin; Avcılar, Hüseyin; Patıroğlu, Türkan; Yıldıran, Alişan; Yeğin, Olcay; Tezcan, Ilhan; Sanal, Ozden; Roos, Dirk

2013-01-01

Chronic granulomatous disease (CGD) is a rare primary immunodeficiency disorder of phagocytes resulting in impaired killing of bacteria and fungi. A mutation in one of the 4 genes encoding the components p22(phox), p47(phox), p67(phox), and p40(phox) of the leukocyte nicotinamide dinucleotide

Thermodynamic and NMR analyses of NADPH binding to lipocalin-type prostaglandin D synthase

International Nuclear Information System (INIS)

Qin, Shubin; Shimamoto, Shigeru; Maruno, Takahiro; Kobayashi, Yuji; Kawahara, Kazuki; Yoshida, Takuya; Ohkubo, Tadayasu

2015-01-01

Lipocalin-type prostaglandin D synthase (L-PGDS) is one of the most abundant proteins in human cerebrospinal fluid (CSF) with dual functions as a prostaglandin D_2 (PGD_2) synthase and a transporter of lipophilic ligands. Recent studies revealed that L-PGDS plays important roles in protecting against various neuronal diseases induced by reactive oxygen species (ROS). However, the molecular mechanisms of such protective actions of L-PGDS remain unknown. In this study, we conducted thermodynamic and nuclear magnetic resonance (NMR) analyses, and demonstrated that L-PGDS binds to nicotinamide coenzymes, including NADPH, NADP"+, and NADH. Although a hydrophilic ligand is not common for L-PGDS, these ligands, especially NADPH showed specific interaction with L-PGDS at the upper pocket of its ligand-binding cavity with an unusually bifurcated shape. The binding affinity of L-PGDS for NADPH was comparable to that previously reported for NADPH oxidases and NADPH in vitro. These results suggested that L-PGDS potentially attenuates the activities of NADPH oxidases through interaction with NADPH. Given that NADPH is the substrate for NADPH oxidases that play key roles in neuronal cell death by generating excessive ROS, these results imply a novel linkage between L-PGDS and ROS. - Highlights: • Interactions of L-PGDS with nicotinamide coenzymes were studied by ITC and NMR. • The binding affinity of L-PGDS was strongest to NADPH among nicotinamide coenzymes. • NADPH binds to the upper part of L-PGDS ligand-binding cavity. • L-PGDS binds to both lipophilic and hydrophilic ligands. • This study implies a novel linkage between L-PGDS and reactive oxygen species.

Hepatic NAD+ deficiency as a therapeutic target for non‐alcoholic fatty liver disease in ageing

Science.gov (United States)

Zhou, Can‐Can; Yang, Xi; Hua, Xia; Liu, Jian; Fan, Mao‐Bing; Li, Guo‐Qiang; Song, Jie; Xu, Tian‐Ying; Li, Zhi‐Yong; Guan, Yun‐Feng

2016-01-01

Abstract Background and Purpose Ageing is an important risk factor of non‐alcoholic fatty liver disease (NAFLD). Here, we investigated whether the deficiency of nicotinamide adenine dinucleotide (NAD+), a ubiquitous coenzyme, links ageing with NAFLD. Experimental Approach Hepatic concentrations of NAD+, protein levels of nicotinamide phosphoribosyltransferase (NAMPT) and several other critical enzymes regulating NAD+ biosynthesis, were compared in middle‐aged and aged mice or patients. The influences of NAD+ decline on the steatosis and steatohepatitis were evaluated in wild‐type and H247A dominant‐negative, enzymically‐inactive NAMPT transgenic mice (DN‐NAMPT) given normal or high‐fat diet (HFD). Key Results Hepatic NAD+ level decreased in aged mice and humans. NAMPT‐controlled NAD+ salvage, but not de novo biosynthesis pathway, was compromised in liver of elderly mice and humans. Given normal chow, middle‐age DN‐NAMPT mice displayed systemic NAD+ reduction and had moderate NAFLD phenotypes, including lipid accumulation, enhanced oxidative stress, triggered inflammation and impaired insulin sensitivity in liver. All these NAFLD phenotypes, especially release of pro‐inflammatory factors, Kupffer cell accumulation, monocytes infiltration, NLRP3 inflammasome pathway and hepatic fibrosis (Masson's staining and α‐SMA staining), deteriorated further under HFD challenge. Oral administration of nicotinamide riboside, a natural NAD+ precursor, completely corrected these NAFLD phenotypes induced by NAD+ deficiency alone or HFD, whereas adenovirus‐mediated SIRT1 overexpression only partially rescued these phenotypes. Conclusions and Implications These results provide the first evidence that ageing‐associated NAD+ deficiency is a critical risk factor for NAFLD, and suggest that supplementation with NAD+ substrates may be a promising therapeutic strategy to prevent and treat NAFLD. PMID:27174364

Biochemical characterization of a new nicotinamidase from an unclassified bacterium thriving in a geothermal water stream microbial mat community.

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Zapata-Pérez, Rubén; Martínez-Moñino, Ana-Belén; García-Saura, Antonio-Ginés; Cabanes, Juana; Takami, Hideto; Sánchez-Ferrer, Álvaro

2017-01-01

Nicotinamidases are amidohydrolases that convert nicotinamide into nicotinic acid, contributing to NAD+ homeostasis in most organisms. In order to increase the number of nicotinamidases described to date, this manuscript characterizes a nicotinamidase obtained from a metagenomic library fosmid clone (JFF054_F02) obtained from a geothermal water stream microbial mat community in a Japanese epithermal mine. The enzyme showed an optimum temperature of 90°C, making it the first hyperthermophilic bacterial nicotinamidase to be characterized, since the phylogenetic analysis of this fosmid clone placed it in a clade of uncultured geothermal bacteria. The enzyme, named as UbNic, not only showed an alkaline optimum pH, but also a biphasic pH dependence of its kcat, with a maximum at pH 9.5-10.0. The two pKa values obtained were 4.2 and 8.6 for pKes1 and pKes2, respectively. These results suggest a possible flexible catalytic mechanism for nicotinamidases, which reconciles the two previously proposed mechanisms. In addition, the enzyme showed a high catalytic efficiency, not only toward nicotinamide, but also toward other nicotinamide analogs. Its mutational analysis showed that a tryptophan (W83) is needed in one of the faces of the active site to maintain low Km values toward all the substrates tested. Furthermore, UbNic proved to contain a Fe2+ ion in its metal binding site, and was revealed to belong to a new nicotinamidase subgroup. All these characteristics, together with its high pH- and thermal stability, distinguish UbNic from previously described nicotinamidases, and suggest that a wide diversity of enzymes remains to be discovered in extreme environments.

Biochemical characterization of a new nicotinamidase from an unclassified bacterium thriving in a geothermal water stream microbial mat community.

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Rubén Zapata-Pérez

Full Text Available Nicotinamidases are amidohydrolases that convert nicotinamide into nicotinic acid, contributing to NAD+ homeostasis in most organisms. In order to increase the number of nicotinamidases described to date, this manuscript characterizes a nicotinamidase obtained from a metagenomic library fosmid clone (JFF054_F02 obtained from a geothermal water stream microbial mat community in a Japanese epithermal mine. The enzyme showed an optimum temperature of 90°C, making it the first hyperthermophilic bacterial nicotinamidase to be characterized, since the phylogenetic analysis of this fosmid clone placed it in a clade of uncultured geothermal bacteria. The enzyme, named as UbNic, not only showed an alkaline optimum pH, but also a biphasic pH dependence of its kcat, with a maximum at pH 9.5-10.0. The two pKa values obtained were 4.2 and 8.6 for pKes1 and pKes2, respectively. These results suggest a possible flexible catalytic mechanism for nicotinamidases, which reconciles the two previously proposed mechanisms. In addition, the enzyme showed a high catalytic efficiency, not only toward nicotinamide, but also toward other nicotinamide analogs. Its mutational analysis showed that a tryptophan (W83 is needed in one of the faces of the active site to maintain low Km values toward all the substrates tested. Furthermore, UbNic proved to contain a Fe2+ ion in its metal binding site, and was revealed to belong to a new nicotinamidase subgroup. All these characteristics, together with its high pH- and thermal stability, distinguish UbNic from previously described nicotinamidases, and suggest that a wide diversity of enzymes remains to be discovered in extreme environments.

Thermodynamic and NMR analyses of NADPH binding to lipocalin-type prostaglandin D synthase

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Qin, Shubin [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Shimamoto, Shigeru [Faculty of Science and Engineering, Kinki University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502 (Japan); Maruno, Takahiro; Kobayashi, Yuji [Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Kawahara, Kazuki; Yoshida, Takuya [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan); Ohkubo, Tadayasu, E-mail: ohkubo@phs.osaka-u.ac.jp [Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871 (Japan)

2015-12-04

Lipocalin-type prostaglandin D synthase (L-PGDS) is one of the most abundant proteins in human cerebrospinal fluid (CSF) with dual functions as a prostaglandin D{sub 2} (PGD{sub 2}) synthase and a transporter of lipophilic ligands. Recent studies revealed that L-PGDS plays important roles in protecting against various neuronal diseases induced by reactive oxygen species (ROS). However, the molecular mechanisms of such protective actions of L-PGDS remain unknown. In this study, we conducted thermodynamic and nuclear magnetic resonance (NMR) analyses, and demonstrated that L-PGDS binds to nicotinamide coenzymes, including NADPH, NADP{sup +}, and NADH. Although a hydrophilic ligand is not common for L-PGDS, these ligands, especially NADPH showed specific interaction with L-PGDS at the upper pocket of its ligand-binding cavity with an unusually bifurcated shape. The binding affinity of L-PGDS for NADPH was comparable to that previously reported for NADPH oxidases and NADPH in vitro. These results suggested that L-PGDS potentially attenuates the activities of NADPH oxidases through interaction with NADPH. Given that NADPH is the substrate for NADPH oxidases that play key roles in neuronal cell death by generating excessive ROS, these results imply a novel linkage between L-PGDS and ROS. - Highlights: • Interactions of L-PGDS with nicotinamide coenzymes were studied by ITC and NMR. • The binding affinity of L-PGDS was strongest to NADPH among nicotinamide coenzymes. • NADPH binds to the upper part of L-PGDS ligand-binding cavity. • L-PGDS binds to both lipophilic and hydrophilic ligands. • This study implies a novel linkage between L-PGDS and reactive oxygen species.

A versatile and highly sensitive homogeneous electrochemical strategy based on the split aptamer binding-induced DNA three-way junction and exonuclease III-assisted target recycling.

Science.gov (United States)

Hou, Ting; Li, Wei; Zhang, Lianfang; Li, Feng

2015-08-21

Herein, a highly sensitive and versatile homogeneous electrochemical biosensing strategy is proposed, based on the split aptamer-incorporated DNA three-way junction and the exonuclease (Exo) III-assisted target recycling. The aptamer of adenosine triphosphate (ATP, chosen as the model analyte) is split into two fragments and embedded in single-stranded DNA1 and DNA2, respectively. ATP specifically binds with the split aptamers, bringing DNA1 and DNA2 close to each other, thus inducing the DNA three-way junction formation through the partial hybridization among DNA1, DNA2 and the methylene blue-labelled MB-DNA. Subsequently, MB-DNA is specifically digested by Exo III, releasing a MB-labelled mononucleotide, as well as a DNA1-ATP-DNA2 complex, which acts as the recycled target and hybridizes with another intact MB-DNA to initiate the subsequent cycling cleavage process. As a result, large amounts of MB-labelled mononucleotides are released, generating a significantly amplified electrochemical signal toward the ATP assay. To the best of our knowledge, it is the first example to successfully incorporate split aptamers into DNA three-way junctions and to be adopted in a homogeneous electrochemical assay. In addition to high sensitivity, this strategy also exhibits the advantages of simplicity and convenience, because it is carried out in a homogeneous solution, and sophisticated electrode modification processes are avoided. By simply changing the sequences of the split aptamer fragments, this versatile strategy can be easily adopted to assay a large spectrum of targets. Due to its advantages of high sensitivity, excellent selectivity, versatility and simple operation, the as-proposed approach has great potential to be applied in biochemical research and clinical practices.