Sample records for nicotinamide

  1. Saccharomyces cerevisiae YOR071C encodes the high affinity nicotinamide riboside transporter Nrt1.

    PubMed

    Belenky, Peter A; Moga, Tiberiu G; Brenner, Charles

    2008-03-28

    NAD(+) is an essential coenzyme for hydride transfer enzymes and a substrate of sirtuins and other NAD(+)-consuming enzymes. Nicotinamide riboside is a recently discovered eukaryotic NAD(+) precursor converted to NAD(+) via the nicotinamide riboside kinase pathway and by nucleosidase activity and nicotinamide salvage. Nicotinamide riboside supplementation of yeast extends replicative life span on high glucose medium. The molecular basis for nicotinamide riboside uptake was unknown in any eukaryote. Here, we show that deletion of a single gene, YOR071C, abrogates nicotinamide riboside uptake without altering nicotinic acid or nicotinamide import. The gene, which is negatively regulated by Sum1, Hst1, and Rfm1, fully restores nicotinamide riboside import and utilization when resupplied to mutant yeast cells. The encoded polypeptide, Nrt1, is a predicted deca-spanning membrane protein related to the thiamine transporter, which functions as a pH-dependent facilitator with a K(m) for nicotinamide riboside of 22 microm. Nrt1-related molecules are conserved in particular fungi, suggesting a similar basis for nicotinamide riboside uptake.

  2. Simultaneous quantitation of nicotinamide riboside, nicotinamide mononucleotide and nicotinamide adenine dinucleotide in milk by a novel enzyme-coupled assay.

    PubMed

    Ummarino, Simone; Mozzon, Massimo; Zamporlini, Federica; Amici, Adolfo; Mazzola, Francesca; Orsomando, Giuseppe; Ruggieri, Silverio; Raffaelli, Nadia

    2017-04-15

    Nicotinamide riboside, the most recently discovered form of vitamin B3, and its phosphorylated form nicotinamide mononucleotide, have been shown to be potent supplements boosting intracellular nicotinamide adenine dinucleotide (NAD) levels, thus preventing or ameliorating metabolic and mitochondrial diseases in mouse models. Here we report for the first time on the simultaneous quantitation of nicotinamide riboside, nicotinamide mononucleotide and NAD in milk by means of a fluorometric, enzyme-coupled assay. Application of this assay to milk from different species revealed that the three vitamers were present in human and donkey milk, while being selectively distributed in the other milks. Human milk was the richest source of nicotinamide mononucleotide. Overall, the three vitamers accounted for a significant fraction of total vitamin B3 content. Pasteurization did not affect the bovine milk content of nicotinamide riboside, whereas UHT processing fully destroyed the vitamin. In human milk, NAD levels were significantly affected by the lactation time. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Excess nicotinamide inhibits methylation-mediated degradation of catecholamines in normotensives and hypertensives.

    PubMed

    Sun, Wu-Ping; Li, Da; Lun, Yong-Zhi; Gong, Xiao-Jie; Sun, Shen-Xia; Guo, Ming; Jing, Li-Xin; Zhang, Li-Bin; Xiao, Fu-Cheng; Zhou, Shi-Sheng

    2012-02-01

    Nicotinamide and catecholamines are both degraded by S-adenosylmethionine-dependent methylation. Whether excess nicotinamide affects the degradation of catecholamines is unknown. The aim of this study was to investigate the effect of nicotinamide on the methylation status of the body and methylation-mediated catecholamine degradation in both normotensives and hypertensives. The study was conducted in 19 normotensives and 27 hypertensives, using a nicotinamide-loading test (100 mg orally). Plasma nicotinamide, N(1)-methylnicotinamide, homocysteine (Hcy), betaine, norepinephrine, epinephrine, normetanephrine and metanephrine levels before and 5 h after nicotinamide loading were measured. Compared with normotensives, hypertensives had higher baseline (fasting) levels of plasma nicotinamide, Hcy and norepinephrine, but lower levels of plasma normetanephrine, a methylated norepinephrine derivative. Nicotinamide loading induced a significant increase in the levels of plasma N(1)-methylnicotinamide and norepinephrine, and a significant decrease in the levels of O-methylated epinephrine (metanephrine) and betaine, a major methyl donor, in both hypertensives and normotensives. Moreover, nicotinamide-loading significantly increased plasma Hcy levels, but decreased plasma normetanephrine levels in normotensives. The baseline levels of plasma epinephrine in hypertensives were similar to those of normotensives, but the post-nicotinamide-loading levels of plasma epinephrine in hypertensives were higher than those of normotensives. This study demonstrated that excess nicotinamide might deplete the labile methyl pool, increase Hcy generation and inhibit catecholamine degradation. It also revealed that hypertensives had an abnormal methylation pattern, characterized by elevated fasting plasma levels of unmethylated substrates, nicotinamide, Hcy and norepinephrine. Therefore, it seems likely that high nicotinamide intake may be involved in the pathogenesis of Hcy-related cardiovascular disease.

  4. Nicotinamide riboside and nicotinic acid riboside salvage in fungi and mammals. Quantitative basis for Urh1 and purine nucleoside phosphorylase function in NAD+ metabolism.

    PubMed

    Belenky, Peter; Christensen, Kathryn C; Gazzaniga, Francesca; Pletnev, Alexandre A; Brenner, Charles

    2009-01-02

    NAD+ is a co-enzyme for hydride transfer enzymes and an essential substrate of ADP-ribose transfer enzymes and sirtuins, the type III protein lysine deacetylases related to yeast Sir2. Supplementation of yeast cells with nicotinamide riboside extends replicative lifespan and increases Sir2-dependent gene silencing by virtue of increasing net NAD+ synthesis. Nicotinamide riboside elevates NAD+ levels via the nicotinamide riboside kinase pathway and by a pathway initiated by splitting the nucleoside into a nicotinamide base followed by nicotinamide salvage. Genetic evidence has established that uridine hydrolase, purine nucleoside phosphorylase, and methylthioadenosine phosphorylase are required for Nrk-independent utilization of nicotinamide riboside in yeast. Here we show that mammalian purine nucleoside phosphorylase but not methylthioadenosine phosphorylase is responsible for mammalian nicotinamide riboside kinase-independent nicotinamide riboside utilization. We demonstrate that so-called uridine hydrolase is 100-fold more active as a nicotinamide riboside hydrolase than as a uridine hydrolase and that uridine hydrolase and mammalian purine nucleoside phosphorylase cleave nicotinic acid riboside, whereas the yeast phosphorylase has little activity on nicotinic acid riboside. Finally, we show that yeast nicotinic acid riboside utilization largely depends on uridine hydrolase and nicotinamide riboside kinase and that nicotinic acid riboside bioavailability is increased by ester modification.

  5. Nicotinamide Riboside and Nicotinic Acid Riboside Salvage in Fungi and Mammals

    PubMed Central

    Belenky, Peter; Christensen, Kathryn C.; Gazzaniga, Francesca; Pletnev, Alexandre A.; Brenner, Charles

    2009-01-01

    NAD+ is a co-enzyme for hydride transfer enzymes and an essential substrate of ADP-ribose transfer enzymes and sirtuins, the type III protein lysine deacetylases related to yeast Sir2. Supplementation of yeast cells with nicotinamide riboside extends replicative lifespan and increases Sir2-dependent gene silencing by virtue of increasing net NAD+ synthesis. Nicotinamide riboside elevates NAD+ levels via the nicotinamide riboside kinase pathway and by a pathway initiated by splitting the nucleoside into a nicotinamide base followed by nicotinamide salvage. Genetic evidence has established that uridine hydrolase, purine nucleoside phosphorylase, and methylthioadenosine phosphorylase are required for Nrk-independent utilization of nicotinamide riboside in yeast. Here we show that mammalian purine nucleoside phosphorylase but not methylthioadenosine phosphorylase is responsible for mammalian nicotinamide riboside kinase-independent nicotinamide riboside utilization. We demonstrate that so-called uridine hydrolase is 100-fold more active as a nicotinamide riboside hydrolase than as a uridine hydrolase and that uridine hydrolase and mammalian purine nucleoside phosphorylase cleave nicotinic acid riboside, whereas the yeast phosphorylase has little activity on nicotinic acid riboside. Finally, we show that yeast nicotinic acid riboside utilization largely depends on uridine hydrolase and nicotinamide riboside kinase and that nicotinic acid riboside bioavailability is increased by ester modification. PMID:19001417

  6. Nicotinamide riboside promotes Sir2 silencing and extends lifespan via Nrk and Urh1/Pnp1/Meu1 pathways to NAD+.

    PubMed

    Belenky, Peter; Racette, Frances G; Bogan, Katrina L; McClure, Julie M; Smith, Jeffrey S; Brenner, Charles

    2007-05-04

    Although NAD(+) biosynthesis is required for Sir2 functions and replicative lifespan in yeast, alterations in NAD(+) precursors have been reported to accelerate aging but not to extend lifespan. In eukaryotes, nicotinamide riboside is a newly discovered NAD(+) precursor that is converted to nicotinamide mononucleotide by specific nicotinamide riboside kinases, Nrk1 and Nrk2. In this study, we discovered that exogenous nicotinamide riboside promotes Sir2-dependent repression of recombination, improves gene silencing, and extends lifespan without calorie restriction. The mechanism of action of nicotinamide riboside is totally dependent on increased net NAD(+) synthesis through two pathways, the Nrk1 pathway and the Urh1/Pnp1/Meu1 pathway, which is Nrk1 independent. Additionally, the two nicotinamide riboside salvage pathways contribute to NAD(+) metabolism in the absence of nicotinamide-riboside supplementation. Thus, like calorie restriction in the mouse, nicotinamide riboside elevates NAD(+) and increases Sir2 function.

  7. Nicotinic acid, nicotinamide, and nicotinamide riboside: a molecular evaluation of NAD+ precursor vitamins in human nutrition.

    PubMed

    Bogan, Katrina L; Brenner, Charles

    2008-01-01

    Although baseline requirements for nicotinamide adenine dinucleotide (NAD+) synthesis can be met either with dietary tryptophan or with less than 20 mg of daily niacin, which consists of nicotinic acid and/or nicotinamide, there is growing evidence that substantially greater rates of NAD+ synthesis may be beneficial to protect against neurological degeneration, Candida glabrata infection, and possibly to enhance reverse cholesterol transport. The distinct and tissue-specific biosynthetic and/or ligand activities of tryptophan, nicotinic acid, nicotinamide, and the newly identified NAD+ precursor, nicotinamide riboside, reviewed herein, are responsible for vitamin-specific effects and side effects. Because current data suggest that nicotinamide riboside may be the only vitamin precursor that supports neuronal NAD+ synthesis, we present prospects for human nicotinamide riboside supplementation and propose areas for future research.

  8. Nicotinamide riboside, a trace nutrient in foods, is a vitamin B3 with effects on energy metabolism and neuroprotection.

    PubMed

    Chi, Yuling; Sauve, Anthony A

    2013-11-01

    This review focuses upon the biology and metabolism of a trace component in foods called nicotinamide riboside. Nicotinamide riboside is a precursor of nicotinamide adenine dinucleotide (NAD), and is a source of Vitamin B3. Evidence indicates that nicotinamide riboside has unique properties as a Vitamin B3. We review knowledge of the metabolism of this substance, as well as recent work suggesting novel health benefits that might be associated with nicotinamide riboside taken in larger quantities than is found naturally in foods. Recent work investigating the effects of nicotinamide riboside in yeast and mammals established that it is metabolized by at least two types of metabolic pathways. The first of these is degradative and produces nicotinamide. The second pathway involves kinases called nicotinamide riboside kinases (Nrk1 and Nrk2, in humans). The likely involvement of the kinase pathway is implicated in the unique effects of nicotinamide riboside in raising tissue NAD concentrations in rodents and for potent effects in eliciting insulin sensitivity, mitochondrial biogenesis, and enhancement of sirtuin functions. Additional studies with nicotinamide riboside in models of Alzheimer's disease indicate bioavailability to brain and protective effects, likely by stimulation of brain NAD synthesis. Initial studies have clarified the potential for a lesser-known Vitamin B3 called nicotinamide riboside that is available in selected foods, and possibly available to humans by supplements. It has properties that are insulin sensitizing, enhancing to exercise, resisting to negative effects of high-fat diet, and neuroprotecting.

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

    PubMed

    Dong, Wei-Ren; Sun, Cen-Cen; Zhu, Guan; Hu, Shi-Hua; Xiang, Li-Xin; Shao, Jian-Zhong

    2014-02-08

    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. 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. 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.

  10. Nicotinamide attenuates the ischemic brain injury-induced decrease of Akt activation and Bad phosphorylation.

    PubMed

    Koh, Phil-Ok

    2011-07-08

    Nicotinamide protects cortical neuronal cells against cerebral ischemic injury through activation of various cytoprotective mechanisms. Here, this study confirmed the neuroprotective effects of nicotinamide in focal cerebral ischemic injury and investigated whether nicotinamide modulates a crucial survival pathway, Akt and its downstream targets. Adult male rats were treated with vehicle or nicotinamide (500 mg/kg) 2h after the onset of middle cerebral artery occlusion (MCAO). Brains were collected 24h after MCAO and infarct volumes were analyzed. Nicotinamide significantly reduced the infarct volume in the cerebral cortex. Potential activation was measured by phosphorylation of PDK1 at Ser(241), Akt at Ser(473), and Bad at Ser(136) using Western blot analysis. Nicotinamide prevented the injury-induced decrease of pPDK1, pAkt, and pBad levels. 14-3-3 levels were not different between vehicle- and nicotinamide-treated animals. However, pBad and 14-3-3 interaction levels decreased during MCAO, but were maintained in the presence of nicotinamide, compared to levels in control animals. These findings suggest that nicotinamide attenuates cell death due to focal cerebral ischemic injury and that neuroprotective effects are mediated through the Akt signaling pathway, thus enhancing neuronal survival. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  11. Nicotinamide megadosing increases hepatic poly(ADP-ribose) levels in choline-deficient rats.

    PubMed

    ApSimon, M M; Rawling, J M; Kirkland, J B

    1995-07-01

    Previous work in our laboratory has shown that dietary megadoses of nicotinamide, used in the prevention of diabetes, cause increases in hepatic poly(ADP-ribose). Poly(ADP-ribose) is synthesized from NAD+ by a nuclear enzyme, poly(ADP-ribose)polymerase, which is activated by DNA strand breaks. The nicotinamide-induced increase in poly(ADP-ribose) could result from an increase in substrate, NAD+, or the induction of strand breaks in DNA. Strand breaks may result from the depletion of single carbon groups, through the excretion of methylated derivatives of nicotinamide. To differentiate between these mechanisms, a 3 x 3 factorial experiment was conducted in which rats were fed diets containing various supplements of choline bitartrate (0, 2, 20 g/kg diet) and nicotinamide (0, 1, 2 g/kg diet). At the conclusion of treatments, blood NAD+ and liver lipid, NAD+ and poly(ADP-ribose) levels were determined. Choline deficiency caused the characteristic accumulation of fat in the liver at all levels of nicotinamide. In choline deficient rats, nicotinamide supplements further increased liver lipid concentration. Blood and liver NAD+ concentrations were increased by nicotinamide supplementation, irrespective of choline status. In contrast, liver poly(ADP-ribose) levels were increased by nicotinamide supplementation only in choline deficient rats. These results show that nicotinamide-induced increases in poly(ADP-ribose) levels appear to be dependent on decreased methyl donor status and suggest that adequate choline status is important for preventing some deleterious effects of nicotinamide treatment.

  12. Nicotinamide pharmacokinetics in humans: effect of gastric acid inhibition, comparison of rectal vs oral administration and the use of saliva for drug monitoring.

    PubMed Central

    Stratford, M. R.; Dennis, M. F.; Hoskin, P.; Phillips, H.; Hodgkiss, R. J.; Rojas, A.

    1996-01-01

    The effect of inhibiting gastric acid secretion on nicotinamide pharmacokinetics was studied in five volunteers with the intent of reducing the large variations observed previously in the time to and magnitude of peak plasma concentrations. Plasma levels were determined using a standard high-performance liquid chromatography (HPLC) method after an oral dose of 3 g of nicotinamide either alone or preceded by pretreatment with omeprazole. Suppression of gastric acid production had no significant effect on the rate of uptake or on the peak levels achieved. To bypass gastric acidity, the rectal route was also assessed using a suppository in four volunteers and one patient undergoing radiotherapy. Absorption was slow and variable and much lower plasma levels were observed than after oral dosing. Thus, no improvement in the pharmacokinetics of nicotinamide was observed using either of these two approaches. Parallel estimations were made using a novel and non-invasive method for monitoring nicotinamide pharmacokinetics in saliva. A large and variable fraction of the total amount of nicotinamide-related material in saliva was found to be nicotinic acid, a metabolite not normally found in human plasma. This conversion was inhibited by the use of a chlorhexidine mouthwash, indicating that the oral flora was responsible for its production. The time to peak levels of nicotinamide or of nicotinamide plus nicotinic acid in saliva correlated well with that in plasma. However, peak concentrations for nicotinamide alone were significantly lower than in plasma, and very variable, whereas for nicotinamide plus nicotinic acid saliva levels were 20-30% higher, but more consistent. Although there are some practical difficulties in quantitatively handling saliva, the method is very useful for monitoring nicotinamide pharmacokinetics and for assessment of compliance with nicotinamide treatment. PMID:8679452

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

    PubMed Central

    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

  14. The Vitamin Nicotinamide: Translating Nutrition into Clinical Care

    PubMed Central

    Maiese, Kenneth; Chong, Zhao Zhong; Hou, Jinling; Shang, Yan Chen

    2009-01-01

    Nicotinamide, the amide form of vitamin B3 (niacin), is changed to its mononucleotide compound with the enzyme nicotinic acide/nicotinamide adenylyl-transferase, and participates in the cellular energy metabolism that directly impacts normal physiology. However, nicotinamide also influences oxidative stress and modulates multiple pathways tied to both cellular survival and death. During disorders that include immune system dysfunction, diabetes, and aging-related diseases, nicotinamide is a robust cytoprotectant that blocks cellular inflammatory cell activation, early apoptotic phosphatidylserine exposure, and late nuclear DNA degradation. Nicotinamide relies upon unique cellular pathways that involve forkhead transcription factors, sirtuins, protein kinase B (Akt), Bad, caspases, and poly (ADP-ribose) polymerase that may offer a fine line with determining cellular longevity, cell survival, and unwanted cancer progression. If one is cognizant of the these considerations, it becomes evident that nicotinamide holds great potential for multiple disease entities, but the development of new therapeutic strategies rests heavily upon the elucidation of the novel cellular pathways that nicotinamide closely governs. PMID:19783937

  15. 21 CFR 172.315 - Nicotinamide-ascorbic acid complex.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Nicotinamide-ascorbic acid complex. 172.315... HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.315 Nicotinamide-ascorbic acid complex. Nicotinamide-ascorbic acid complex may be safely used in accordance with the following prescribed conditions...

  16. Discoveries of nicotinamide riboside as a nutrient and conserved NRK genes establish a Preiss-Handler independent route to NAD+ in fungi and humans.

    PubMed

    Bieganowski, Pawel; Brenner, Charles

    2004-05-14

    NAD+ is essential for life in all organisms, both as a coenzyme for oxidoreductases and as a source of ADPribosyl groups used in various reactions, including those that retard aging in experimental systems. Nicotinic acid and nicotinamide were defined as the vitamin precursors of NAD+ in Elvehjem's classic discoveries of the 1930s. The accepted view of eukaryotic NAD+ biosynthesis, that all anabolism flows through nicotinic acid mononucleotide, was challenged experimentally and revealed that nicotinamide riboside is an unanticipated NAD+ precursor in yeast. Nicotinamide riboside kinases from yeast and humans essential for this pathway were identified and found to be highly specific for phosphorylation of nicotinamide riboside and the cancer drug tiazofurin. Nicotinamide riboside was discovered as a nutrient in milk, suggesting that nicotinamide riboside is a useful compound for elevation of NAD+ levels in humans.

  17. In vitro evaluation of nicotinamide riboside analogs against Haemophilus influenzae.

    PubMed Central

    Godek, C P; Cynamon, M H

    1990-01-01

    Exogenous NAD, nicotinamide mononucleotide, or nicotinamide riboside is required for the growth of Haemophilus influenzae. These compounds have been defined as the V-factor growth requirement. We have previously shown that the internalization of nicotinamide riboside is energy dependent and carrier mediated with saturation kinetics. Thionicotinamide riboside, 3-pyridinealdehyde riboside, 3-acetylpyridine riboside, and 3-aminopyridine riboside were prepared from their corresponding NAD analogs. These compounds and several other nicotinamide riboside analogs were evaluated for their ability to support the growth of H. influenzae and for their ability to block the uptake of [carbonyl-14C]nicotinamide riboside by H. influenzae. 3-Aminopyridine riboside blocked the uptake of [carbonyl-14C]nicotinamide riboside and inhibited the growth of H. influenzae when NAD, nicotinamide mononucleotide, or nicotinamide riboside served as the V factor. The antibacterial activity of 3-aminopyridine riboside was found to be specific for H. influenzae but had no effect on the growth of Staphylococcus aureus or Escherichia coli. In additional experiments by reversed-phase high-performance liquid chromatography, it was determined that whole cells of H. influenzae degrade 3-aminopyridine adenine dinucleotide to 3-aminopyridine riboside, which is then internalized. Inside the cell, 3-aminopyridine riboside has the ability to interfere with the growth of H. influenzae by an undetermined mechanism. Images PMID:2145800

  18. In vitro evaluation of nicotinamide riboside analogs against Haemophilus influenzae.

    PubMed

    Godek, C P; Cynamon, M H

    1990-08-01

    Exogenous NAD, nicotinamide mononucleotide, or nicotinamide riboside is required for the growth of Haemophilus influenzae. These compounds have been defined as the V-factor growth requirement. We have previously shown that the internalization of nicotinamide riboside is energy dependent and carrier mediated with saturation kinetics. Thionicotinamide riboside, 3-pyridinealdehyde riboside, 3-acetylpyridine riboside, and 3-aminopyridine riboside were prepared from their corresponding NAD analogs. These compounds and several other nicotinamide riboside analogs were evaluated for their ability to support the growth of H. influenzae and for their ability to block the uptake of [carbonyl-14C]nicotinamide riboside by H. influenzae. 3-Aminopyridine riboside blocked the uptake of [carbonyl-14C]nicotinamide riboside and inhibited the growth of H. influenzae when NAD, nicotinamide mononucleotide, or nicotinamide riboside served as the V factor. The antibacterial activity of 3-aminopyridine riboside was found to be specific for H. influenzae but had no effect on the growth of Staphylococcus aureus or Escherichia coli. In additional experiments by reversed-phase high-performance liquid chromatography, it was determined that whole cells of H. influenzae degrade 3-aminopyridine adenine dinucleotide to 3-aminopyridine riboside, which is then internalized. Inside the cell, 3-aminopyridine riboside has the ability to interfere with the growth of H. influenzae by an undetermined mechanism.

  19. Role of nicotinamide (vitamin B3) in acetaminophen-induced changes in rat liver: Nicotinamide effect in acetaminophen-damged liver.

    PubMed

    Mahmoud, Yomna I; Mahmoud, Asmaa A

    2016-06-01

    Acetaminophen is a widely used analgesic and antipyretic agent, which is safe at therapeutic doses. However, overdoses of acetaminophen induce severe oxidative stress, which leads to acute liver failure. Nicotinamide has proven effective in ameliorating many pathological conditions that occur due to oxidative stress. This study verifies the prophylactic and therapeutic effects of nicotinamide against the hepatic pathophysiological and ultrastructural alterations induced by acetaminophen. Wistar rats intoxicated with an acute overdose of acetaminophen (5g/kg b.wt) were given a single dose of nicotinamide (500mg/kg b.wt) either before or after intoxication. Acetaminophen caused significant elevation in the liver functions and lipid peroxidation marker, and decline in the activities of the hepatic antioxidant enzymes. This oxidative injury was associated with hepatic centrilobular necrosis, hemorrage, vacuolar degeneration, lipid accumulation and mitochondrial alterations. Treating intoxicated rats with nicotinamide (500mg/kg) significantly ameliorated acetaminophen-induced biochemical changes and pathological injuries. However, administering the same dose of nicotinamide to healthy animals or prior to acetaminophen-intoxication induced hepatotoxicity. Caution should be taken when administering high doses of NAM because of its possible hepatotoxicity. Considering the wide use of nicotinamide, there is an important need for monitoring nicotinamide tolerance, safety and efficacy in healthy and diseased subjects. Copyright © 2016 Elsevier GmbH. All rights reserved.

  20. Nicotinamide Suppresses the DNA Damage Sensitivity of Saccharomyces cerevisiae Independently of Sirtuin Deacetylases.

    PubMed

    Rössl, Anthony; Bentley-DeSousa, Amanda; Tseng, Yi-Chieh; Nwosu, Christine; Downey, Michael

    2016-10-01

    Nicotinamide is both a reaction product and an inhibitor of the conserved sirtuin family of deacetylases, which have been implicated in a broad range of cellular functions in eukaryotes from yeast to humans. Phenotypes observed following treatment with nicotinamide are most often assumed to stem from inhibition of one or more of these enzymes. Here, we used this small molecule to inhibit multiple sirtuins at once during treatment with DNA damaging agents in the Saccharomyces cerevisiae model system. Since sirtuins have been previously implicated in the DNA damage response, we were surprised to observe that nicotinamide actually increased the survival of yeast cells exposed to the DNA damage agent MMS. Remarkably, we found that enhanced resistance to MMS in the presence of nicotinamide was independent of all five yeast sirtuins. Enhanced resistance was also independent of the nicotinamide salvage pathway, which uses nicotinamide as a substrate to generate NAD+, and of a DNA damage-induced increase in the salvage enzyme Pnc1 Our data suggest a novel and unexpected function for nicotinamide that has broad implications for its use in the study of sirtuin biology across model systems. Copyright © 2016 by the Genetics Society of America.

  1. Nicotinamide Suppresses the DNA Damage Sensitivity of Saccharomyces cerevisiae Independently of Sirtuin Deacetylases

    PubMed Central

    Rössl, Anthony; Bentley-DeSousa, Amanda; Tseng, Yi-Chieh; Nwosu, Christine; Downey, Michael

    2016-01-01

    Nicotinamide is both a reaction product and an inhibitor of the conserved sirtuin family of deacetylases, which have been implicated in a broad range of cellular functions in eukaryotes from yeast to humans. Phenotypes observed following treatment with nicotinamide are most often assumed to stem from inhibition of one or more of these enzymes. Here, we used this small molecule to inhibit multiple sirtuins at once during treatment with DNA damaging agents in the Saccharomyces cerevisiae model system. Since sirtuins have been previously implicated in the DNA damage response, we were surprised to observe that nicotinamide actually increased the survival of yeast cells exposed to the DNA damage agent MMS. Remarkably, we found that enhanced resistance to MMS in the presence of nicotinamide was independent of all five yeast sirtuins. Enhanced resistance was also independent of the nicotinamide salvage pathway, which uses nicotinamide as a substrate to generate NAD+, and of a DNA damage-induced increase in the salvage enzyme Pnc1. Our data suggest a novel and unexpected function for nicotinamide that has broad implications for its use in the study of sirtuin biology across model systems. PMID:27527516

  2. Structural Basis for Nicotinamide Inhibition and Base Exchange in Sir2 Enzymes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sanders, B.; Zhao, K; Slama, J

    2007-01-01

    The Sir2 family of proteins consists of broadly conserved NAD+-dependent deacetylases that are implicated in diverse biological processes, including DNA regulation, metabolism, and longevity. Sir2 proteins are regulated in part by the cellular concentrations of a noncompetitive inhibitor, nicotinamide, that reacts with a Sir2 reaction intermediate via a base-exchange reaction to reform NAD+ at the expense of deacetylation. To gain a mechanistic understanding of nicotinamide inhibition in Sir2 enzymes, we captured the structure of nicotinamide bound to a Sir2 homolog, yeast Hst2, in complex with its acetyl-lysine 16 histone H4 substrate and a reaction intermediate analog, ADP-HPD. Together with relatedmore » biochemical studies and structures, we identify a nicotinamide inhibition and base-exchange site that is distinct from the so-called 'C pocket' binding site for the nicotinamide group of NAD+. These results provide insights into the Sir2 mechanism of nicotinamide inhibition and have important implications for the development of Sir2-specific effectors.« less

  3. Identification of Isn1 and Sdt1 as Glucose- and Vitamin-regulated Nicotinamide Mononucleotide and Nicotinic Acid Mononucleotide 5′-Nucleotidases Responsible for Production of Nicotinamide Riboside and Nicotinic Acid Riboside*

    PubMed Central

    Bogan, Katrina L.; Evans, Charles; Belenky, Peter; Song, Peng; Burant, Charles F.; Kennedy, Robert; Brenner, Charles

    2009-01-01

    Recently, we discovered that nicotinamide riboside and nicotinic acid riboside are biosynthetic precursors of NAD+, which are utilized through two pathways consisting of distinct enzymes. In addition, we have shown that exogenously supplied nicotinamide riboside is imported into yeast cells by a dedicated transporter, and it extends replicative lifespan on high glucose medium. Here, we show that nicotinamide riboside and nicotinic acid riboside are authentic intracellular metabolites in yeast. Secreted nicotinamide riboside was detected with a biological assay, and intracellular levels of nicotinamide riboside, nicotinic acid riboside, and other NAD+ metabolites were determined by a liquid chromatography-mass spectrometry method. A biochemical genomic screen indicated that three yeast enzymes possess nicotinamide mononucleotide 5′-nucleotidase activity in vitro. Metabolic profiling of knock-out mutants established that Isn1 and Sdt1 are responsible for production of nicotinamide riboside and nicotinic acid riboside in cells. Isn1, initially classified as an IMP-specific 5′-nucleotidase, and Sdt1, initially classified as a pyrimidine 5′-nucleotidase, are additionally responsible for dephosphorylation of pyridine mononucleotides. Sdt1 overexpression is growth-inhibitory to cells in a manner that depends on its active site and correlates with reduced cellular NAD+. Expression of Isn1 protein is positively regulated by the availability of nicotinic acid and glucose. These results reveal unanticipated and highly regulated steps in NAD+ metabolism. PMID:19846558

  4. Identification of Isn1 and Sdt1 as glucose- and vitamin-regulated nicotinamide mononucleotide and nicotinic acid mononucleotide [corrected] 5'-nucleotidases responsible for production of nicotinamide riboside and nicotinic acid riboside.

    PubMed

    Bogan, Katrina L; Evans, Charles; Belenky, Peter; Song, Peng; Burant, Charles F; Kennedy, Robert; Brenner, Charles

    2009-12-11

    Recently, we discovered that nicotinamide riboside and nicotinic acid riboside are biosynthetic precursors of NAD(+), which are utilized through two pathways consisting of distinct enzymes. In addition, we have shown that exogenously supplied nicotinamide riboside is imported into yeast cells by a dedicated transporter, and it extends replicative lifespan on high glucose medium. Here, we show that nicotinamide riboside and nicotinic acid riboside are authentic intracellular metabolites in yeast. Secreted nicotinamide riboside was detected with a biological assay, and intracellular levels of nicotinamide riboside, nicotinic acid riboside, and other NAD(+) metabolites were determined by a liquid chromatography-mass spectrometry method. A biochemical genomic screen indicated that three yeast enzymes possess nicotinamide mononucleotide 5'-nucleotidase activity in vitro. Metabolic profiling of knock-out mutants established that Isn1 and Sdt1 are responsible for production of nicotinamide riboside and nicotinic acid riboside in cells. Isn1, initially classified as an IMP-specific 5'-nucleotidase, and Sdt1, initially classified as a pyrimidine 5'-nucleotidase, are additionally responsible for dephosphorylation of pyridine mononucleotides. Sdt1 overexpression is growth-inhibitory to cells in a manner that depends on its active site and correlates with reduced cellular NAD(+). Expression of Isn1 protein is positively regulated by the availability of nicotinic acid and glucose. These results reveal unanticipated and highly regulated steps in NAD(+) metabolism.

  5. Nicotinamide inhibits the growth of P. falciparum and enhances the antimalarial effect of artemisinin, chloroquine and pyrimethamine.

    PubMed

    Tcherniuk, Sergey O; Chesnokova, Olga; Oleinikov, Irina V; Oleinikov, Andrew V

    2017-09-01

    Nicotinamide (vitamin B3) - is a water soluble amide derivative of nicotinic acid, which has been used at high doses for a variety of therapeutic applications. However, its antimalarial effect has not been intensively explored. In this work we analysed the effect of nicotinamide alone and in combination with artemisinin, chloroquine andpyrimethamine on the growth of blood stages of P. falciparum. Our results demonstrate that nicotinamide effectively inhibits the growth of blood stage parasites with IC 50 of 6.9±0.1mM and 2.2±0.3mM for CS2 and 3G8 strains, respectively. The combination of nicotinamide with artemisinin, chloroquine and pyrimethamine demonstrated synergistic effects at IC 10-90%. Treatment of uninfected red blood cells with high dose of nicotinamide (60mM) did not provoke the significant LDH release, demonstrating its non-toxicity for erythrocytes. Nicotinamide acts below the level of tolerance and reduces the effective concentration of anti-malarial drugs due to synergism. These in vitro results suggest that nicotinamide might be useful not only as a vitamin supplement but also as an enhancer of the anti-parasitic effect of common antimalarial drugs including artemisinin, chloroquine and pyrimethamine. Published by Elsevier B.V.

  6. Navigating novel mechanisms of cellular plasticity with the NAD+ precursor and nutrient nicotinamide.

    PubMed

    Li, Faqi; Chong, Zhao Zhong; Maiese, Kenneth

    2004-09-01

    Interest in neuroprotectants for the central nervous system continues to garner significant attention. Nicotinamide, the amide form of niacin (vitamin B3), is the precursor for the coenzyme beta-nicotinamide adenine dinucleotide (NAD+) and is considered to be necessary for cellular function and metabolism. However, recent work has focused on the development of nicotinamide as a novel agent that is critical for modulating cellular plasticity, longevity, and inflammatory microglial function. The ability of nicotinamide to preserve both neuronal and vascular cell populations in the brain during injury is intriguing, but further knowledge of the specific cellular mechanisms that determine protection by this agent is required. The capacity of nicotinamide to govern not only intrinsic cellular integrity, but also extrinsic cellular inflammation rests with the modulation of a host of cellular targets that involve protein kinase B, glycogen synthase kinase-3 beta (GSK-3 beta), Forkhead transcription factors, mitochondrial dysfunction, poly(ADP-ribose) polymerase, cysteine proteases, and microglial activation. Intimately tied to the cytoprotection of nicotinamide is the modulation of an early and late phase of apoptotic injury that is triggered by the loss of membrane asymmetry. Identifying robust cytoprotective agents as nicotinamide in conjunction with the elucidation of the cellular mechanisms responsible for cell survival will continue to solidify the development of therapeutic strategies against neurodegenerative diseases

  7. Nrt1 and Tna1-Independent Export of NAD+ Precursor Vitamins Promotes NAD+ Homeostasis and Allows Engineering of Vitamin Production

    PubMed Central

    Belenky, Peter; Stebbins, Rebecca; Bogan, Katrina L.; Evans, Charles R.; Brenner, Charles

    2011-01-01

    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. PMID:21589930

  8. Evaluation of nicotinamide microemulsion on the skin penetration enhancement.

    PubMed

    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.

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

    PubMed

    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(+).

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

    PubMed

    Belenky, Peter; Stebbins, Rebecca; Bogan, Katrina L; Evans, Charles R; Brenner, Charles

    2011-05-11

    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.

  11. Computational vibrational study on coordinated nicotinamide

    NASA Astrophysics Data System (ADS)

    Bolukbasi, Olcay; Akyuz, Sevim

    2005-06-01

    The molecular structure and vibrational spectra of zinc (II) halide complexes of nicotinamide (ZnX 2(NIA) 2; X=Cl or Br; NIA=Nicotinamide) were investigated by computational vibrational study and scaled quantum mechanical (SQM) analysis. The geometry optimisation and vibrational wavenumber calculations of zinc halide complexes of nicotinamide were carried out by using the DFT/RB3LYP level of theory with 6-31G(d,p) basis set. The calculated wavenumbers were scaled by using scaled quantum mechanical (SQM) force field method. The fundamental vibrational modes were characterised by their total energy distribution. The coordination effects on nicotinamide through the ring nitrogen were discussed.

  12. Nicotinamide extends replicative lifespan of human cells.

    PubMed

    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.

  13. The Copper-nicotinamide complex: sustainable applications in coupling and cycloaddition reactions

    EPA Science Inventory

    Crystalline copper (II)-nicotinamide complex, synthesized via simple mixing of copper chloride and nicotinamide solution at room temperature, catalyzes the C-S, C-N bond forming and cycloaddition reactions under a variety of sustainable reaction conditions.

  14. Nicotinamide improves sevoflurane-induced cognitive impairment through suppression of inflammation and anti-apoptosis in rat

    PubMed Central

    Wang, Ying; Zuo, Min

    2015-01-01

    Nicotinamide is amide form of vitamin B3, participate in oxidation-reduction reaction, and it plays an important role in the maintenance of normal life activities in cells; it has broad application prospects in the treatment of heart blood-vessel disease, respiratory disease, type 1 diabetes and inflammatory autoimmune diseases. Thus the present study aimed to identify whether the nicotinamide improves sevoflurane-induced cognitive impairment and its potential mechanisms in rat. Firstly, Male Sprague-Dawley rats were induced by 2.1% sevoflurane for 6 h. Protective function of nicotinamide on cognitive impairment was evaluated using Morris water maze test in the rats. Next, NF-κB and caspase-3 activities, and p53, Bax and Bcl-2 protein expression was executed using commercial kits and Western blot analysis, respectively. Preconditioning with nicotinamide could improve cognitive impairment in the rats. Administrate of nicotinamide suppressed the activation of NF-κB and caspase-3, reduced the protein expression of Bax, and promoted Bcl-2 protein expression in rats. The present results suggested nicotinamide improves sevoflurane-induced cognitive impairment and has an anti-inflammatory and anti-apoptotic effect against sevoflrane-induced damages. PMID:26884920

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

    PubMed

    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.

  16. Structural Basis of Substrate Recognition in Human Nicotinamide N-Methyltransferase

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Peng, Yi; Sartini, Davide; Pozzi, Valentina

    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 inmore » 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.« less

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

    PubMed

    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.

  18. 21 CFR 172.315 - Nicotinamide-ascorbic acid complex.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... (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...: (a) The additive is the product of the controlled reaction between ascorbic acid and nicotinamide...

  19. 21 CFR 172.315 - Nicotinamide-ascorbic acid complex.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... (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...: (a) The additive is the product of the controlled reaction between ascorbic acid and nicotinamide...

  20. Nicotinamide Inhibits the Lysosomal Cathepsin b-like Protease and Kills African Trypanosomes*

    PubMed Central

    Unciti-Broceta, Juan D.; Maceira, José; Morales, Sonia; García-Pérez, Angélica; Muñóz-Torres, Manuel E.; Garcia-Salcedo, Jose A.

    2013-01-01

    Nicotinamide, a soluble compound of the vitamin B3 group, has antimicrobial activity against several microorganisms ranging from viruses to parasite protozoans. However, the mode of action of this antimicrobial activity is unknown. Here, we investigate the trypanocidal activity of nicotinamide on Trypanosoma brucei, the causative agent of African trypanosomiasis. Incubation of trypanosomes with nicotinamide causes deleterious defects in endocytic traffic, disruption of the lysosome, failure of cytokinesis, and, ultimately, cell death. At the same concentrations there was no effect on a cultured mammalian cell line. The effects on endocytosis and vesicle traffic were visible within 3 h and can be attributed to inhibition of lysosomal cathepsin b-like protease activity. The inhibitory effect of nicotinamide was confirmed by a direct activity assay of recombinant cathepsin b-like protein. Taken together, these data demonstrate that inhibition of the lysosomal protease cathepsin b-like blocks endocytosis, causing cell death. In addition, these results demonstrate for the first time the inhibitory effect of nicotinamide on a protease. PMID:23443665

  1. Nicotinamide riboside kinase structures reveal new pathways to NAD+.

    PubMed

    Tempel, Wolfram; Rabeh, Wael M; Bogan, Katrina L; Belenky, Peter; Wojcik, Marzena; Seidle, Heather F; Nedyalkova, Lyudmila; Yang, Tianle; Sauve, Anthony A; Park, Hee-Won; Brenner, Charles

    2007-10-02

    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+.

  2. NRK1 controls nicotinamide mononucleotide and nicotinamide riboside metabolism in mammalian cells.

    PubMed

    Ratajczak, Joanna; Joffraud, Magali; Trammell, Samuel A J; Ras, Rosa; Canela, Núria; Boutant, Marie; Kulkarni, Sameer S; Rodrigues, Marcelo; Redpath, Philip; Migaud, Marie E; Auwerx, Johan; Yanes, Oscar; Brenner, Charles; Cantó, Carles

    2016-10-11

    NAD + is a vital redox cofactor and a substrate required for activity of various enzyme families, including sirtuins and poly(ADP-ribose) polymerases. Supplementation with NAD + precursors, such as nicotinamide mononucleotide (NMN) or nicotinamide riboside (NR), protects against metabolic disease, neurodegenerative disorders and age-related physiological decline in mammals. Here we show that nicotinamide riboside kinase 1 (NRK1) is necessary and rate-limiting for the use of exogenous NR and NMN for NAD + synthesis. Using genetic gain- and loss-of-function models, we further demonstrate that the role of NRK1 in driving NAD + synthesis from other NAD + precursors, such as nicotinamide or nicotinic acid, is dispensable. Using stable isotope-labelled compounds, we confirm NMN is metabolized extracellularly to NR that is then taken up by the cell and converted into NAD + . Our results indicate that mammalian cells require conversion of extracellular NMN to NR for cellular uptake and NAD + synthesis, explaining the overlapping metabolic effects observed with the two compounds.

  3. The Influence of Nicotinamide on Health and Disease in the Central Nervous System

    PubMed Central

    Fricker, Rosemary A; Green, Emma L; Jenkins, Stuart I; Griffin, Síle M

    2018-01-01

    Nicotinamide, the amide form of vitamin B3 (niacin), has long been associated with neuronal development, survival, and function in the central nervous system (CNS), being implicated in both neuronal death and neuroprotection. Here, we summarise a body of research investigating the role of nicotinamide in neuronal health within the CNS, with a focus on studies that have shown a neuroprotective effect. Nicotinamide appears to play a role in protecting neurons from traumatic injury, ischaemia, and stroke, as well as being implicated in 3 key neurodegenerative conditions: Alzheimer’s, Parkinson’s, and Huntington’s diseases. A key factor is the bioavailability of nicotinamide, with low concentrations leading to neurological deficits and dementia and high levels potentially causing neurotoxicity. Finally, nicotinamide’s potential mechanisms of action are discussed, including the general maintenance of cellular energy levels and the more specific inhibition of molecules such as the nicotinamide adenine dinucleotide-dependent deacetylase, sirtuin 1 (SIRT1). PMID:29844677

  4. NRK1 controls nicotinamide mononucleotide and nicotinamide riboside metabolism in mammalian cells

    PubMed Central

    Ratajczak, Joanna; Joffraud, Magali; Trammell, Samuel A. J.; Ras, Rosa; Canela, Núria; Boutant, Marie; Kulkarni, Sameer S.; Rodrigues, Marcelo; Redpath, Philip; Migaud, Marie E.; Auwerx, Johan; Yanes, Oscar; Brenner, Charles; Cantó, Carles

    2016-01-01

    NAD+ is a vital redox cofactor and a substrate required for activity of various enzyme families, including sirtuins and poly(ADP-ribose) polymerases. Supplementation with NAD+ precursors, such as nicotinamide mononucleotide (NMN) or nicotinamide riboside (NR), protects against metabolic disease, neurodegenerative disorders and age-related physiological decline in mammals. Here we show that nicotinamide riboside kinase 1 (NRK1) is necessary and rate-limiting for the use of exogenous NR and NMN for NAD+ synthesis. Using genetic gain- and loss-of-function models, we further demonstrate that the role of NRK1 in driving NAD+ synthesis from other NAD+ precursors, such as nicotinamide or nicotinic acid, is dispensable. Using stable isotope-labelled compounds, we confirm NMN is metabolized extracellularly to NR that is then taken up by the cell and converted into NAD+. Our results indicate that mammalian cells require conversion of extracellular NMN to NR for cellular uptake and NAD+ synthesis, explaining the overlapping metabolic effects observed with the two compounds. PMID:27725675

  5. Nicotinamide Forestalls Pathology and Cognitive Decline in Alzheimer Mice: Evidence for Improved Neuronal Bioenergetics and Autophagy Procession

    PubMed Central

    Liu, Dong; Pitta, Michael; Jiang, Haiyang; Lee, Jong-Hwan; Zhang, Guofeng; Chen, Xinzhi; Kawamoto, Elisa M.; Mattson, Mark P.

    2012-01-01

    Impaired brain energy metabolism and oxidative stress are implicated in cognitive decline and the pathological accumulations of amyloid β-peptide (Aβ) and hyperphosphorylated Tau (p-Tau) in Alzheimer's disease (AD). To determine whether improving brain energy metabolism will forestall disease progress in AD, the impact of the NAD+ precursor nicotinamide on brain cell mitochondrial function and macroautophagy, bioenergetics-related signaling and cognitive performance were studied in cultured neurons and in a mouse model of AD. Oxidative stress resulted in decreased mitochondrial mass, mitochondrial degeneration and autophagosome accumulation in neurons. Nicotinamide preserved mitochondrial integrity and autophagy function, and reduced neuronal vulnerability to oxidative/metabolic insults and Aβ toxicity. NAD+ biosynthesis, autophagy and PI3K signaling were required for the neuroprotective action of nicotinamide. Treatment of 3xTgAD mice with nicotinamide for 8 months resulted in improved cognitive performance, and reduced Aβ and p-Tau pathologies in hippocampus and cerebral cortex. Nicotinamide treatment preserved mitochondrial integrity, and improved autophagy-lysosome procession by enhancing lysosome/autolysosome acidification to reduce autophagosome accumulation. Treatment of 3xTgAD mice with nicotinamide resulted in elevated levels of activated neuroplasticity-related kinases (Akt and ERKs) and the transcription factor cyclic AMP response element-binding protein in the hippocampus and cerebral cortex. Thus, nicotinamide suppresses AD pathology and cognitive decline in a mouse model of AD by a mechanism involving improved brain bioenergetics with preserved functionality of mitochondria and the autophagy system. PMID:23273573

  6. Nicotinamide riboside kinases display redundancy in mediating nicotinamide mononucleotide and nicotinamide riboside metabolism in skeletal muscle cells.

    PubMed

    Fletcher, Rachel S; Ratajczak, Joanna; Doig, Craig L; Oakey, Lucy A; Callingham, Rebecca; Da Silva Xavier, Gabriella; Garten, Antje; Elhassan, Yasir S; Redpath, Philip; Migaud, Marie E; Philp, Andrew; Brenner, Charles; Canto, Carles; Lavery, Gareth G

    2017-08-01

    Augmenting nicotinamide adenine dinucleotide (NAD + ) availability may protect skeletal muscle from age-related metabolic decline. Dietary supplementation of NAD + precursors nicotinamide mononucleotide (NMN) and nicotinamide riboside (NR) appear efficacious in elevating muscle NAD + . Here we sought to identify the pathways skeletal muscle cells utilize to synthesize NAD + from NMN and NR and provide insight into mechanisms of muscle metabolic homeostasis. We exploited expression profiling of muscle NAD + biosynthetic pathways, single and double nicotinamide riboside kinase 1/2 (NRK1/2) loss-of-function mice, and pharmacological inhibition of muscle NAD + recycling to evaluate NMN and NR utilization. Skeletal muscle cells primarily rely on nicotinamide phosphoribosyltransferase (NAMPT), NRK1, and NRK2 for salvage biosynthesis of NAD + . NAMPT inhibition depletes muscle NAD + availability and can be rescued by NR and NMN as the preferred precursors for elevating muscle cell NAD + in a pathway that depends on NRK1 and NRK2. Nrk2 knockout mice develop normally and show subtle alterations to their NAD+ metabolome and expression of related genes. NRK1, NRK2, and double KO myotubes revealed redundancy in the NRK dependent metabolism of NR to NAD + . Significantly, these models revealed that NMN supplementation is also dependent upon NRK activity to enhance NAD + availability. These results identify skeletal muscle cells as requiring NAMPT to maintain NAD + availability and reveal that NRK1 and 2 display overlapping function in salvage of exogenous NR and NMN to augment intracellular NAD + availability.

  7. 21 CFR 172.315 - Nicotinamide-ascorbic acid complex.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.315 Nicotinamide-ascorbic acid complex. Nicotinamide-ascorbic acid complex may be safely used in accordance with the following prescribed conditions: (a) The additive is the product of...

  8. 21 CFR 573.625 - Menadione nicotinamide bisulfite.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.625 Menadione nicotinamide bisulfite. The food additive may be safely... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Menadione nicotinamide bisulfite. 573.625 Section...

  9. 21 CFR 573.625 - Menadione nicotinamide bisulfite.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.625 Menadione nicotinamide bisulfite. The food additive may be safely... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Menadione nicotinamide bisulfite. 573.625 Section...

  10. 21 CFR 573.625 - Menadione nicotinamide bisulfite.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.625 Menadione nicotinamide bisulfite. The food additive may be safely... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Menadione nicotinamide bisulfite. 573.625 Section...

  11. 21 CFR 573.625 - Menadione nicotinamide bisulfite.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.625 Menadione nicotinamide bisulfite. The food additive may be safely... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Menadione nicotinamide bisulfite. 573.625 Section...

  12. 21 CFR 573.625 - Menadione nicotinamide bisulfite.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES PERMITTED IN FEED AND DRINKING WATER OF ANIMALS Food Additive Listing § 573.625 Menadione nicotinamide bisulfite. The food additive may be safely... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Menadione nicotinamide bisulfite. 573.625 Section...

  13. Nicotinamide alone accelerates the conversion of mouse embryonic stem cells into mature neuronal populations

    PubMed Central

    Griffin, Síle M.; Pickard, Mark R.; Orme, Rowan P.; Hawkins, Clive P.; Williams, Adrian C.

    2017-01-01

    Introduction Vitamin B3 has been shown to play an important role during embryogenesis. Specifically, there is growing evidence that nicotinamide, the biologically active form of vitamin B3, plays a critical role as a morphogen in the differentiation of stem cells to mature cell phenotypes, including those of the central nervous system (CNS). Detailed knowledge of the action of small molecules during neuronal differentiation is not only critical for uncovering mechanisms underlying lineage-specification, but also to establish more effective differentiation protocols to obtain clinically relevant cells for regenerative therapies for neurodegenerative conditions such as Huntington’s disease (HD). Thus, this study aimed to investigate the potential of nicotinamide to promote the conversion of stem cells to mature CNS neurons. Methods Nicotinamide was applied to differentiating mouse embryonic stem cells (mESC; Sox1GFP knock-in 46C cell line) during their conversion towards a neural fate. Cells were assessed for changes in their proliferation, differentiation and maturation; using immunocytochemistry and morphometric analysis methods. Results Results presented indicate that 10 mM nicotinamide, when added at the initial stages of differentiation, promoted accelerated progression of ESCs to a neural lineage in adherent monolayer cultures. By 14 days in vitro (DIV), early exposure to nicotinamide was shown to increase the numbers of differentiated βIII-tubulin-positive neurons. Nicotinamide decreased the proportion of pluripotent stem cells, concomitantly increasing numbers of neural progenitors at 4 DIV. These progenitors then underwent rapid conversion to neurons, observed by a reduction in Sox 1 expression and decreased numbers of neural progenitors in the cultures at 14 DIV. Furthermore, GABAergic neurons generated in the presence of nicotinamide showed increased maturity and complexity of neurites at 14 DIV. Therefore, addition of nicotinamide alone caused an accelerated passage of pluripotent cells through lineage specification and further to non-dividing mature neurons. Conclusions Our results show that, within an optimal dose range, nicotinamide is able to singly and selectively direct the conversion of embryonic stem cells to mature neurons, and therefore may be a critical factor for normal brain development, thus supporting previous evidence of the fundamental role of vitamins and their metabolites during early CNS development. In addition, nicotinamide may offer a simple effective supplement to enhance the conversion of stem cells to clinically relevant neurons. PMID:28817722

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

    PubMed

    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 recommended, but longer follow-up is required to determine whether nicotinamide should be continued beyond this period.

  15. Nicotinamide Riboside Preserves Cardiac Function in a Mouse Model of Dilated Cardiomyopathy.

    PubMed

    Diguet, Nicolas; Trammell, Samuel A J; Tannous, Cynthia; Deloux, Robin; Piquereau, Jérôme; Mougenot, Nathalie; Gouge, Anne; Gressette, Mélanie; Manoury, Boris; Blanc, Jocelyne; Breton, Marie; Decaux, Jean-François; Lavery, Gareth G; Baczkó, István; Zoll, Joffrey; Garnier, Anne; Li, Zhenlin; Brenner, Charles; Mericskay, Mathias

    2018-05-22

    Myocardial metabolic impairment is a major feature in chronic heart failure. As the major coenzyme in fuel oxidation and oxidative phosphorylation and a substrate for enzymes signaling energy stress and oxidative stress response, nicotinamide adenine dinucleotide (NAD + ) is emerging as a metabolic target in a number of diseases including heart failure. Little is known on the mechanisms regulating homeostasis of NAD + in the failing heart. To explore possible alterations of NAD + homeostasis in the failing heart, we quantified the expression of NAD + biosynthetic enzymes in the human failing heart and in the heart of a mouse model of dilated cardiomyopathy (DCM) triggered by Serum Response Factor transcription factor depletion in the heart (SRF HKO ) or of cardiac hypertrophy triggered by transverse aorta constriction. We studied the impact of NAD + precursor supplementation on cardiac function in both mouse models. We observed a 30% loss in levels of NAD + in the murine failing heart of both DCM and transverse aorta constriction mice that was accompanied by a decrease in expression of the nicotinamide phosphoribosyltransferase enzyme that recycles the nicotinamide precursor, whereas the nicotinamide riboside kinase 2 (NMRK2) that phosphorylates the nicotinamide riboside precursor is increased, to a higher level in the DCM (40-fold) than in transverse aorta constriction (4-fold). This shift was also observed in human failing heart biopsies in comparison with nonfailing controls. We show that the Nmrk2 gene is an AMP-activated protein kinase and peroxisome proliferator-activated receptor α responsive gene that is activated by energy stress and NAD + depletion in isolated rat cardiomyocytes. Nicotinamide riboside efficiently rescues NAD + synthesis in response to FK866-mediated inhibition of nicotinamide phosphoribosyltransferase and stimulates glycolysis in cardiomyocytes. Accordingly, we show that nicotinamide riboside supplementation in food attenuates the development of heart failure in mice, more robustly in DCM, and partially after transverse aorta constriction, by stabilizing myocardial NAD + levels in the failing heart. Nicotinamide riboside treatment also robustly increases the myocardial levels of 3 metabolites, nicotinic acid adenine dinucleotide, methylnicotinamide, and N1-methyl-4-pyridone-5-carboxamide, that can be used as validation biomarkers for the treatment. The data show that nicotinamide riboside, the most energy-efficient among NAD precursors, could be useful for treatment of heart failure, notably in the context of DCM, a disease with few therapeutic options. © 2017 American Heart Association, Inc.

  16. Nicotinamide-rich diet improves physical endurance by up-regulating SUR2A in the heart

    PubMed Central

    Sukhodub, Andriy; Sudhir, Rajni; Du, Qingyou; Jovanović, Sofija; Reyes, Santiago; Jovanović, Aleksandar

    2011-01-01

    Abstract SUR2A is an ATP-binding protein that serves as a regulatory subunit of cardioprotective ATP-sensitive K+ (KATP) channels. Based on signalling pathway regulating SUR2A expression and SUR2A role in regulating numbers of fully assembled KATP channels, we have suggested that nicotinamide-rich diet could improve physical endurance by stimulating SUR2A expression. We have found that mice on nicotinamide-rich diet significantly improved physical endurance, which was associated with significant increase in expression of SUR2A. Transgenic mice with solely overexpressed SUR2A on control diet had increased physical endurance in a similar manner as the wild-type mice on nicotinamide-rich diet. The experiments focused on action membrane potential and intracellular Ca2+ concentration have demonstrated that increased SUR2A expression was associated with the activation of sarcolemmal KATP channels and steady Ca2+ levels in cardiomyocytes in response to β-adrenergic stimulation. In contrast, the same challenge in the wild-type was characterized by a lack of the channel activation and rise in intracellular Ca2+. Nicotinamide-rich diet was ineffective to increase physical endurance in mice lacking KATP channels. This study has shown that nicotinamide-rich diet improves physical endurance by increasing expression of SUR2A and that this is a sole mechanism of the nicotinamide-rich diet effect. The obtained results suggest that oral nicotinamide is a regulator of SUR2A expression and has a potential as a drug that can improve physical endurance in conditions where this effect would be desirable. PMID:20731746

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

    NASA Astrophysics Data System (ADS)

    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.

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

    PubMed Central

    Williams, Adrian C; Hill, Lisa J

    2017-01-01

    Hunting for meat was a critical step in all animal and human evolution. A key brain-trophic element in meat is vitamin B3 / 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. PMID:28579800

  19. Crystallization of human nicotinamide phosphoribosyltransferase

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Takahashi, Ryo; Nakamura, Shota; Yoshida, Takuya

    2007-05-01

    Human nicotinamide phosphoribosyltransferase has been crystallized using microseeding methods and X-ray diffraction data have been collected at 2.0 Å resolution. In the NAD biosynthetic pathway, nicotinamide phosphoribosyltransferase (NMPRTase; EC 2.4.2.12) plays an important role in catalyzing the synthesis of nicotinamide mononucleotide from nicotinamide and 5′-phosphoribosyl-1′-pyrophosphate. Because the diffraction pattern of the initally obtained crystals was not suitable for structure analysis, the crystal quality was improved by successive use of the microseeding technique. The resultant crystals diffracted to 2.0 Å resolution. These crystals belonged to space group P21, with unit-cell parameters a = 60.56, b = 106.40, c = 82.78 Å.more » Here, the crystallization of human NMPRTase is reported in the free form; the crystals should be useful for inhibitor-soaking experiments on the enzyme.« less

  20. Enzymatic synthesis of polymers containing nicotinamide mononucleotide

    NASA Technical Reports Server (NTRS)

    Liu, Rihe

    1995-01-01

    Nicotinamide mononucleoside 5'-diphosphate in its reduced form is an excellent substrate for polynucleotide phosphorylase from Micrococcus luteus both in de novo polymerization reactions and in primer extension reactions. The oxidized form of the diphosphate is a much less efficient substrate; it can be used to extend primers but does not oligomerize in the absence of a primer. The cyanide adduct of the oxidized substrate, like the reduced substrate, polymerizes efficiently. Loss of cyanide yields high molecular weight polymers of the oxidized form. Terminal transferase from calf thymus accepts nicotinamide mononucleoside 5'-triphosphate as a substrate and efficiently adds one residue to the 3'-end of an oligodeoxynucleotide. T4 polynucleotide kinase accepts oligomers of nicotinamide mononucleotide as substrates. However, RNA polymerases do not incorporate nicotinamide mononucleoside 5'-triphosphate into products on any of the templates that we used.

  1. Enzymatic Synthesis of Polymers Containing Nicotinamide Mononucleotide

    NASA Technical Reports Server (NTRS)

    Liu, Rihe; Orgel, Leslie E.

    1995-01-01

    Nicotinamide mononucleoside 5'-diphosphate in its reduced form is an excellent substrate for polynucleotide phosphorylase from Micrococcus luteus both in de novo polymerization reactions and in primer extension reactions. The oxidized form of the diphosphate is a much less efficient substrate; it can be used to extend primers but does not oligomerize in the absence of a primer. The cyanide adduct of the oxidized substrate, like the reduced substrate, polymerizes efficiently. Loss of cyanide yields high molecular weight polymers of the oxidized form. Terminal transferase from calf thymus accepts nicotinamide mononucleoside 5'-triphosphate as a substrate and efficiently adds one residue to the 3'-end of an oligodeoxynucleotide. T4 polynucleotide kinase accepts oligomers of nicotinamide mononucleotide as substrates. However, RNA polymerases do not incorporate nicotinamide mononucleoside 5'-triphosphate into products on any of the templates that we used.

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

    PubMed

    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 further assess the safety and efficacy of nicotinamide in human glaucoma care.

  3. [Metabolic disturbance of tryptophan-nicotinamide conversion pathway by putative endocrine disruptors, bisphenol A and styrene monomer].

    PubMed

    Fukuwatari, Tsutomu; Toriochi, Mai; Ohta, Mari; Sasaki, Ryuzo; Shibata, Katsumi

    2004-02-01

    Bisphenol A, a monomer of polycarbonate plastics, disturbed the conversion pathway of the amino acid tryptophan to the vitamin nicotinamide. The conversion ratio of tryptophan to nicotinamide was reduced to 1/15 by feeding a diet containing 1% bisphenol A. A putative disturbing reaction is kynurenine-->3-hydroxykynurenine, which is catalyzed by kynurenine monohydroxylase. This is an FAD-enzyme and requires NADPH as a coenzyme. Styrene monomer (1% addition to a normal diet) did not affect the food intake or the body weight, but slightly reduced the conversion ratio of tryptophan-nicotinamide.

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

    PubMed

    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.

  5. HPLC determination of olanzapine and carbamazepine in their nicotinamide cocrystals and investigation of the dissolution profiles of cocrystal tablet formulations.

    PubMed

    Renkoğlu, Pelin; Çelebier, Mustafa; Arıca-Yegin, Betül

    2015-05-01

    Cocrystals have recently gained importance in the pharmaceutical industry. In this study, olanzapine and carbamazepine cocrystals were synthesized by using nicotinamide as cocrystal forming agent to achieve improvements in the physicochemical characteristics of the active ingredients. An HPLC method was developed to determine the amount, thus, the stoichiometric ratios of olanzapine and carbamazepine in the synthesized cocrystals. Olanzapine:nicotinamide and olanzapine tablet formulations were prepared and the developed HPLC method was applied successfully in order to compare the dissolution profiles of these formulations. An ACE 5 CN, 25 cm × 4.6 mm, 5 µm column was used and a gradient elution program was performed for simultaneous determination of olanzapine, carbamazepine and nicotinamide. Phosphate buffer (pH 5.0, 25 mM) and methanol was used in a ratio from 80:20 to 70:30 while the flow rate was 1 mL min(-1) for the elution of the compounds within 12 min. In conclusion, two different aims were achieved, the first one was to indicate the stoichiometric ratios of the active ingredients olanzapine and carbamazepine with nicotinamide in their cocrystals, and the second one was the comparison of the dissolution profiles of the olanzapine and olanzapine:nicotinamide cocrystal formulations. It was found that the cocrystal formulation with nicotinamide improved the dissolution profile of olanzapine.

  6. Nicotinamide adenine dinucleotide is transported into mammalian mitochondria.

    PubMed

    Davila, Antonio; Liu, Ling; Chellappa, Karthikeyani; Redpath, Philip; Nakamaru-Ogiso, Eiko; Paolella, Lauren M; Zhang, Zhigang; Migaud, Marie E; Rabinowitz, Joshua D; Baur, Joseph A

    2018-06-12

    Mitochondrial NAD levels influence fuel selection, circadian rhythms, and cell survival under stress. It has alternately been argued that NAD in mammalian mitochondria arises from import of cytosolic nicotinamide (NAM), nicotinamide mononucleotide (NMN), or NAD itself. We provide evidence that murine and human mitochondria take up intact NAD. Isolated mitochondria preparations cannot make NAD from NAM, and while NAD is synthesized from NMN, it does not localize to the mitochondrial matrix or effectively support oxidative phosphorylation. Treating cells with nicotinamide riboside that is isotopically labeled on the nicotinamide and ribose moieties results in the appearance of doubly labeled NAD within mitochondria. Analogous experiments with doubly labeled nicotinic acid riboside (labeling cytosolic NAD without labeling NMN) demonstrate that NAD(H) is the imported species. Our results challenge the long-held view that the mitochondrial inner membrane is impermeable to pyridine nucleotides and suggest the existence of an unrecognized mammalian NAD (or NADH) transporter. © 2018, Davila et al.

  7. Regeneration of Nicotinamide Coenzymes: Principles and Applications for the Synthesis of Chiral Compounds

    NASA Astrophysics Data System (ADS)

    Weckbecker, Andrea; Gröger, Harald; Hummel, Werner

    Dehydrogenases which depend on nicotinamide coenzymes are of increasing interest for the preparation of chiral compounds, either by reduction of a prochiral precursor or by oxidative resolution of their racemate. The regeneration of oxidized and reduced nicotinamide cofactors is a very crucial step because the use of these cofactors in stoichiometric amounts is too expensive for application. There are several possibilities to regenerate nicotinamide cofactors: established methods such as formate/formate dehydrogenase (FDH) for the regeneration of NADH, recently developed electrochemical methods based on new mediator structures, or the application of gene cloning methods for the construction of "designed" cells by heterologous expression of appropriate genes.

  8. Syntheses of nicotinamide riboside and derivatives: effective agents for increasing nicotinamide adenine dinucleotide concentrations in mammalian cells.

    PubMed

    Yang, Tianle; Chan, Noel Yan-Ki; Sauve, Anthony A

    2007-12-27

    A new two-step methodology achieves stereoselective synthesis of beta-nicotinamide riboside and a series of related amide, ester, and acid nucleosides. Compounds were prepared through a triacetylated-nicotinate ester nucleoside, via coupling of either ethylnicotinate or phenylnicotinate with 1,2,3,5-tetra-O-acetyl-beta-D-ribofuranose. Nicotinamide riboside, nicotinic acid riboside, O-ethylnicotinate riboside, O-methylnicotinate riboside, and several N-alkyl derivatives increased NAD+ concentrations from 1.2-2.7-fold in several mammalian cell lines. These findings establish bioavailability and potent effects of these nucleosides in stimulating the increase of NAD+ concentrations in mammalian cells.

  9. Purification and characterization of the enzymes involved in nicotinamide adenine dinucleotide degradation by Penicillium brevicompactum NRC 829.

    PubMed

    Ali, Thanaa Hamed; El-Ghonemy, Dina Helmy

    2016-06-01

    The present study was conducted to investigate a new pathway for the degradation of nicotinamide adenine dinucleotide (NAD) by Penicillium brevicompactum NRC 829 extracts. Enzymes involved in the hydrolysis of NAD, i.e. alkaline phosphatase, aminohydrolase and glycohydrolase were determined. Alkaline phosphatase was found to catalyse the sequential hydrolysis of two phosphate moieties of NAD molecule to nicotinamide riboside plus adenosine. Adenosine was then deaminated by aminohydrolase to inosine and ammonia. While glycohydrolase catalyzed the hydrolysis of the nicotinamide-ribosidic bond of NAD+ to produce nicotinamide and ADP-ribose in equimolar amounts, enzyme purification through a 3-step purification procedure revealed the existence of two peaks of alkaline phosphatases, and one peak contained deaminase and glycohydrolase activities. NAD deaminase was purified to homogeneity as estimated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis with an apparent molecular mass of 91 kDa. Characterization and determination of some of NAD aminohydrolase kinetic properties were conducted due to its biological role in the regulation of cellular NAD level. The results also revealed that NAD did not exert its feedback control on nicotinamide amidase produced by P. brevicompactum.

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

    PubMed

    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.

  11. Quantitative Analysis of NAD Synthesis-Breakdown Fluxes.

    PubMed

    Liu, Ling; Su, Xiaoyang; Quinn, William J; Hui, Sheng; Krukenberg, Kristin; Frederick, David W; Redpath, Philip; Zhan, Le; Chellappa, Karthikeyani; White, Eileen; Migaud, Marie; Mitchison, Timothy J; Baur, Joseph A; Rabinowitz, Joshua D

    2018-05-01

    The redox cofactor nicotinamide adenine dinucleotide (NAD) plays a central role in metabolism and is a substrate for signaling enzymes including poly-ADP-ribose-polymerases (PARPs) and sirtuins. NAD concentration falls during aging, which has triggered intense interest in strategies to boost NAD levels. A limitation in understanding NAD metabolism has been reliance on concentration measurements. Here, we present isotope-tracer methods for NAD flux quantitation. In cell lines, NAD was made from nicotinamide and consumed largely by PARPs and sirtuins. In vivo, NAD was made from tryptophan selectively in the liver, which then excreted nicotinamide. NAD fluxes varied widely across tissues, with high flux in the small intestine and spleen and low flux in the skeletal muscle. Intravenous administration of nicotinamide riboside or mononucleotide delivered intact molecules to multiple tissues, but the same agents given orally were metabolized to nicotinamide in the liver. Thus, flux analysis can reveal tissue-specific NAD metabolism. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. A Phosphoenzyme Mimic, Overlapping Catalytic Sites and Reaction Coordinate Motion for Human NAMPT

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Burgos, E.; Ho, M; Almo, S

    2009-01-01

    Nicotinamide phosphoribosyltransferase (NAMPT) is highly evolved to capture nicotinamide (NAM) and replenish the nicotinamide adenine dinucleotide (NAD+) pool during ADP-ribosylation and transferase reactions. ATP-phosphorylation of an active-site histidine causes catalytic activation, increasing NAM affinity by 160,000. Crystal structures of NAMPT with catalytic site ligands identify the phosphorylation site, establish its role in catalysis, demonstrate unique overlapping ATP and phosphoribosyltransferase sites, and establish reaction coordinate motion. NAMPT structures with beryllium fluoride indicate a covalent H247-BeF3- as the phosphohistidine mimic. Activation of NAMPT by H247-phosphorylation causes stabilization of the enzyme-phosphoribosylpyrophosphate complex, permitting efficient capture of NAM. Reactant and product structures establish reactionmore » coordinate motion for NAMPT to be migration of the ribosyl anomeric carbon from the pyrophosphate leaving group to the nicotinamide-N1 while the 5-phosphoryl group, the pyrophosphate moiety, and the nicotinamide ring remain fixed in the catalytic site.« less

  13. Cocrystal of Ibuprofen⁻Nicotinamide: Solid-State Characterization and In Vivo Analgesic Activity Evaluation.

    PubMed

    Yuliandra, Yori; Zaini, Erizal; Syofyan, Syofyan; Pratiwi, Wenny; Putri, Lidiya Novita; Pratiwi, Yuti Sahra; Arifin, Helmi

    2018-06-04

    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.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vaca, Pilar; Berna, Genoveva; Araujo, Raquel

    2008-03-10

    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.more » 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.« less

  15. Nicotinamide adenine dinucleotide biosynthesis promotes liver regeneration.

    PubMed

    Mukherjee, Sarmistha; Chellappa, Karthikeyani; Moffitt, Andrea; Ndungu, Joan; Dellinger, Ryan W; Davis, James G; Agarwal, Beamon; Baur, Joseph A

    2017-02-01

    The regenerative capacity of the liver is essential for recovery from surgical resection or injuries induced by trauma or toxins. During liver regeneration, the concentration of nicotinamide adenine dinucleotide (NAD) falls, at least in part due to metabolic competition for precursors. To test whether NAD availability restricts the rate of liver regeneration, we supplied nicotinamide riboside (NR), an NAD precursor, in the drinking water of mice subjected to partial hepatectomy. NR increased DNA synthesis, mitotic index, and mass restoration in the regenerating livers. Intriguingly, NR also ameliorated the steatosis that normally accompanies liver regeneration. To distinguish the role of hepatocyte NAD levels from any systemic effects of NR, we generated mice overexpressing nicotinamide phosphoribosyltransferase, a rate-limiting enzyme for NAD synthesis, specifically in the liver. Nicotinamide phosphoribosyltransferase overexpressing mice were mildly hyperglycemic at baseline and, similar to mice treated with NR, exhibited enhanced liver regeneration and reduced steatosis following partial hepatectomy. Conversely, mice lacking nicotinamide phosphoribosyltransferase in hepatocytes exhibited impaired regenerative capacity that was completely rescued by administering NR. NAD availability is limiting during liver regeneration, and supplementation with precursors such as NR may be therapeutic in settings of acute liver injury. (Hepatology 2017;65:616-630). © 2016 by the American Association for the Study of Liver Diseases.

  16. Stimulation of nicotinamide adenine dinucleotide biosynthetic pathways delays axonal degeneration after axotomy.

    PubMed

    Sasaki, Yo; Araki, Toshiyuki; Milbrandt, Jeffrey

    2006-08-16

    Axonal degeneration occurs in many neurodegenerative diseases and after traumatic injury and is a self-destructive program independent from programmed cell death. Previous studies demonstrated that overexpression of nicotinamide mononucleotide adenylyltransferase 1 (Nmnat1) or exogenous application of nicotinamide adenine dinucleotide (NAD) can protect axons of cultured dorsal root ganglion (DRG) neurons from degeneration caused by mechanical or neurotoxic injury. In mammalian cells, NAD can be synthesized from multiple precursors, including tryptophan, nicotinic acid, nicotinamide, and nicotinamide riboside (NmR), via multiple enzymatic steps. To determine whether other components of these NAD biosynthetic pathways are capable of delaying axonal degeneration, we overexpressed each of the enzymes involved in each pathway and/or exogenously administered their respective substrates in DRG cultures and assessed their capacity to protect axons after axotomy. Among the enzymes tested, Nmnat1 had the strongest protective effects, whereas nicotinamide phosphoribosyl transferase and nicotinic acid phosphoribosyl transferase showed moderate protective activity in the presence of their substrates. Strong axonal protection was also provided by Nmnat3, which is predominantly located in mitochondria, and an Nmnat1 mutant localized to the cytoplasm, indicating that the subcellular location of NAD production is not crucial for protective activity. In addition, we showed that exogenous application of the NAD precursors that are the substrates of these enzymes, including nicotinic acid mononucleotide, nicotinamide mononucleotide, and NmR, can also delay axonal degeneration. These results indicate that stimulation of NAD biosynthetic pathways via a variety of interventions may be useful in preventing or delaying axonal degeneration.

  17. Nicotinamide Inhibits Vasculogenic Mimicry, an Alternative Vascularization Pathway Observed in Highly Aggressive Melanoma

    PubMed Central

    Shalmon, Bruria; Kubi, Adva; Treves, Avraham J.; Shapira-Frommer, Ronnie; Avivi, Camilla; Ortenberg, Rona; Ben-Ami, Eytan; Schachter, Jacob; Besser, Michal J.; Markel, Gal

    2013-01-01

    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. PMID:23451174

  18. Nicotinamide riboside phosphorylase from beef liver: purification and characterization.

    PubMed

    Imai, T; Anderson, B M

    1987-04-01

    Nicotinamide riboside phosphorylase (NR phosphorylase) from beef liver has been purified to apparent homogeneity at 300-fold purification with a 35% yield. Kinetic constants for the enzyme-catalyzed phosphorolysis were as follows Knicotinamide riboside, 2.5 +/- 0.4 mM; Kinorganic phosphate, 0.50 +/- 0.12 mM; Vmax, 410 +/- 30 X 10(-6) mol min-1 mg protein-1, respectively. The molecular weights of the native enzyme and subunit structure were determined to be 131,000 and 32,000, respectively, suggesting the beef liver NR phosphorylase to be tetrameric in structure and consistent with the presence of identical subunits. The amino acid composition was shown to be very similar to that reported for human erythrocyte purine-nucleoside phosphorylase but differing considerably from that found for rat liver purine-nucleoside phosphorylase. In addition to catalytic activity with nicotinamide riboside, the beef liver enzyme catalyzed a phosphorolytic reaction with inosine and guanosine exhibiting activity ratios, nicotinamide riboside:inosine: guanosine of 1.00:0.35:0.29, respectively. These ratios of activity remained constant throughout purification of the beef liver enzyme and no separation of these activities was detected. Phosphorolysis of nicotinamide riboside was inhibited competitively by inosine (Ki = 75 microM) and guanosine (Ki = 75 microM). Identical rates of thermal denaturation of the beef liver enzyme were observed when determined for the phosphorolysis of either nicotinamide riboside or inosine. These observations coupled with studies of pH and specific buffer effects indicate the phosphorolysis of nicotinamide riboside, inosine, and guanosine to be catalyzed by the same enzyme.

  19. Big brains, meat, tuberculosis and the nicotinamide switches: co-evolutionary relationships with modern repercussions on longevity and disease?

    PubMed

    Williams, Adrian C; Dunbar, Robin I M

    2014-07-01

    Meat eating has been an important trigger for human evolution however the responsible component in meat has not been clearly identified. Here we propose that the limiting factors for expanding brains and increasing longevity were the micronutrient nicotinamide (vitamin B3) and the metabolically related essential amino-acid, tryptophan. Meat offers significant sourcing challenges and lack causes a deficiency of nicotinamide and tryptophan and consequently the energy carrier nicotinamide adenine dinucleotide (NAD) that gets consumed in regulatory circuits important for survival, resulting in premature ageing, poor cognition and brain atrophy. If a trophic supply of dietary nicotinamide/tryptophan is so essential for building brains, constraining their size and connectivity, we hypothesise that back-up mechanisms to ensure the supply evolved. One strategy may be increasing the reliance on gut symbionts to break down celluloses that produces NADH and only nicotinamide indirectly, and may cause diarrhoea. We suggest that a direct supplier was the chronic mycobacterial infection tuberculosis (TB) that is a surprise candidate but it co-evolved early, does not inevitably cause disease (90-95% of those infected are healthy), and secretes (and is inhibited by) nicotinamide. We hypothesise that TB evolved first as a symbiont that enabled humans to cope with short-lived shortages of meat and only later behaved as a pathogen when the supply deteriorated chronically, for those in poverty. (TB immunology and epidemiology is riddled with paradoxes for a conventional pathogen). We test this in pilot data showing that sharp declines in TB (and diarrhoea) - `environmental enteropathy' strongly correlate with increasing meat consumption and therefore nicotinamide exposure, unlike later onset cancers and Parkinson's disease that increased in incidence, perhaps - as we propose a hypothetical hypervitaminosis B3 (to include obesity and the metabolic syndrome) - as the trade-off for increased brain power and longevity, a recently evolved human characteristic. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Theophylline-nicotinamide cocrystal formation in physical mixture during storage.

    PubMed

    Ervasti, Tuomas; Aaltonen, Jaakko; Ketolainen, Jarkko

    2015-01-01

    Pharmaceutically relevant properties, such as solubility and dissolution rate, of active pharmaceutical ingredients can be enhanced by cocrystal formation. Theophylline and nicotinamide are known to form cocrystals, for example if subjected to solid-state grinding. However, under appropriate conditions, cocrystals can also form in physical mixtures without any mechanical activation. The purpose of this work was to study whether theophylline and nicotinamide could form cocrystals spontaneously, without mechanical activation. Crystalline theophylline and nicotinamide powders were gently mixed manually in a 1:1 molar ratio and stored at different relative humidity and temperature conditions. The solid state of the samples was analyzed by differential scanning calorimetry, Raman spectroscopy and X-ray powder diffractometry. Three different variations of theophylline were used as starting materials, e.g., two size fractions of theophylline anhydrate (large 710 μm-1 mm and small 180-355 μm), and monohydrate (recrystallized from water). As a reference, anhydrous theophylline-nicotinamide cocrystals were prepared by solid-state grinding. The results of this study indicate that theophylline-nicotinamide cocrystals can form without any mechanical activation from physical mixtures of theophylline and nicotinamide during storage. For anhydrous samples, storage humidity was found to be a critical parameter for cocrystal formation. Increasing temperature was also found to have an accelerating effect on the transformation. The effect of particle size of anhydrous theophylline on the transformation rate could not be completely resolved; DSC and Raman indicated slightly faster transformation with a physical mixture prepared from large size fraction of anhydrous theophylline, but the differences were only minor. Cocrystal formation was also observed in the physical mixture prepared from theophylline monohydrate, but the rate was not as high as with samples prepared from anhydrous material. Copyright © 2015 Elsevier B.V. All rights reserved.

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

    PubMed

    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 Biology, Inc.

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

    PubMed Central

    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

  3. Adenylate and Nicotinamide Nucleotides in Developing Soybean Seeds During Seed-Fill 1

    PubMed Central

    Quebedeaux, Bruno

    1981-01-01

    Profiles of adenylate and nicotinamide nucleotides in soybean seeds were determined during seed-fill. The ATP content per seed increased during the early seed-filling stages to a level of 10 to 12 micrograms per seed. Seed ATP decreased after 40 days of development and reached its lowest level of less than 1 microgram at maturity. The ATP:ADP ratios were relatively constant at all seed development stages. Sharp increases in AMP levels during the late seed-fill stages were paralleled with a disappearance of ATP and ADP pools resulting in a reduced seed energy charge. Energy charge varied from the highest value of 0.78 at mid-seed-fill to less than 0.10 at maturity. Of the oxidized (NAD, NADP) and reduced (NADH, NADPH) nicotinamide nucleotide forms, NAD was the most abundant. Levels as high as 17.5 micrograms per seed were observed during the mid-seed-filling stages. NADP was found almost exclusively in the reduced form with a NADP: NADPH ratio of less than 0.35, whereas the reverse was noted for NAD which was found mainly in the oxidized form with a NAD:NADH ratio in the range of 5 to 25. NADP was detected in low concentrations compared to the other adenylate and nicotinamide nucleotides. The nicotinamide redox charge defined as (NADH + NADPH)/(NAD + NADH) + (NADP + NADPH) was calculated to express the state of the energy balance between the oxidized and reduced nicotinamide nucleotide forms. The nicotinamide redox charge varied between 0.15 and 0.30 during seed development and was significantly lower than that found for the adenylate energy charge. PMID:16661875

  4. Nicotinamide pre-treatment ameliorates NAD(H) hyperoxidation and improves neuronal function after severe hypoxia

    PubMed Central

    Shetty, Pavan K; Galeffi, Francesca; Turner, Dennis A.

    2014-01-01

    Prolonged hypoxia leads to irreversible loss of neuronal function and metabolic impairment of nicotinamide adenine dinucleotide recycling (between NAD+ and NADH) immediately after reoxygenation, resulting in NADH hyperoxidation. We test whether addition of nicotinamide (to enhance NAD+ levels) or PARP-1 inhibition (to prevent consumption of NAD+) can be effective in improving either loss of neuronal function or hyperoxidation following severe hypoxic injury in hippocampal slices. After severe, prolonged hypoxia (maintained for 3 min after spreading depression) there was hyperoxidation of NADH following reoxygenation, an increased soluble NAD+/NADH ratio, loss of neuronal field excitatory post-synaptic potential (fEPSP) and decreased ATP content. Nicotinamide incubation (5 mM) 2 hr prior to hypoxia significantly increased total NAD(H) content, improved neuronal recovery, enhanced ATP content, and prevented NADH hyperoxidation. The nicotinamide-induced increase in total soluble NAD(H) was more significant in the cytosolic compartment than within mitochondria. Prolonged incubation with PJ-34 (>1hr) led to enhanced baseline NADH fluorescence prior to hypoxia, as well as improved neuronal recovery, NADH hyperoxidation and ATP content on recovery from severe hypoxia and reoxygenation. In this acute model of severe neuronal dysfunction prolonged incubation with either nicotinamide or PJ-34 prior to hypoxia improved recovery of neuronal function, enhanced NADH reduction and ATP content, but neither treatment restored function when administered during or after prolonged hypoxia and reoxygenation. PMID:24184921

  5. PnuC and the utilization of the nicotinamide riboside analog 3-aminopyridine in Haemophilus influenzae.

    PubMed

    Sauer, Elizabeta; Merdanovic, Melisa; Mortimer, Anne Price; Bringmann, Gerhard; Reidl, Joachim

    2004-12-01

    The utilization pathway for the uptake of NAD and nicotinamide riboside was previously characterized for Haemophilus influenzae. We now report on the cellular location, topology, and substrate specificity of PnuC. pnuC of H. influenzae is only distantly related to pnuC of Escherichia coli and Salmonella enterica serovar Typhimurium. When E. coli PnuC was expressed in an H. influenzae pnuC mutant, it was able to take up only nicotinamide riboside and not nicotinamide mononucleotide. Therefore, we postulated that PnuC transporters in general possess specificity for nicotinamide riboside. Earlier studies showed that 3-aminopyridine derivatives (e.g., 3-aminopyridine adenine dinucleotide) are inhibitory for H. influenzae growth. By testing characterized strains with mutations in the NAD utilization pathway, we show that 3-aminopyridine riboside is inhibitory to H. influenzae and is taken up by the NAD-processing and nicotinamide riboside route. 3-Aminopyridine riboside is utilized effectively in a pnuC+ background. In addition, we demonstrate that 3-aminopyridine adenine dinucleotide resynthesis is produced by NadR. 3-Aminopyridine riboside-resistant H. influenzae isolates were characterized, and mutations in nadR could be detected. We also tested other species of the family Pasteurellaceae, Pasteurella multocida and Actinobacillus actinomycetemcomitans, and found that 3-aminopyridine riboside does not act as a growth inhibitor; hence, 3-aminopyridine riboside represents an anti-infective agent with a very narrow host range.

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

    PubMed

    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.

  7. Action of nucleotide phosphotransferase of Escherichia coli on nicotinamide riboside and nicotinamide mononucleotide.

    PubMed Central

    Brunngraber, E F; Chargaff, E

    1977-01-01

    The action of the nucleotide phosphotransferase of Escherichia coli on nicotinamide riboside and on its 5'-phosphate results in the addition of one phosphate moiety to each of the substrates. Although the proof is not conclusive, it is likely that the phosphate group is transferred to the 3'-hydroxyl of the ribose. This is in contrast to the behavior of the enzyme toward NAD in which only the adenylic acid portion is phosphorylated enzymically. PMID:144913

  8. Assimilation of nicotinamide mononucleotide requires periplasmic AphA phosphatase in Salmonella enterica.

    PubMed

    Grose, Julianne H; Bergthorsson, Ulfar; Xu, Yaping; Sterneckert, Jared; Khodaverdian, Behzad; Roth, John R

    2005-07-01

    Salmonella enterica can obtain pyridine from exogenous nicotinamide mononucleotide (NMN) by three routes. In route 1, nicotinamide is removed from NMN in the periplasm and enters the cell as the free base. In route 2, described here, phosphate is removed from NMN in the periplasm by acid phosphatase (AphA), and the produced nicotinamide ribonucleoside (NmR) enters the cell via the PnuC transporter. Internal NmR is then converted back to NMN by the NmR kinase activity of NadR. Route 3 is seen only in pnuC* transporter mutants, which import NMN intact and can therefore grow on lower levels of NMN. Internal NMN produced by either route 2 or route 3 is deamidated to nicotinic acid mononucleotide and converted to NAD by the biosynthetic enzymes NadD and NadE.

  9. NAD+ maintenance attenuates light induced photoreceptor degeneration Δ

    PubMed Central

    Bai, Shi; Sheline, Christian T.

    2013-01-01

    Light-induced retinal damage (LD) occurs after surgery or sun exposure. We previously showed that zinc (Zn2+) accumulated in photoreceptors and RPE cells after LD but prior to cell death, and pyruvate or nicotinamide attenuated the resultant death perhaps by restoring nicotinamide adenine dinucleotide (NAD+) levels. We first examined the levels of NAD+ and the efficacy of pyruvate or nicotinamide in oxidative toxicities using primary retinal cultures. We next manipulated NAD+ levels in vivo and tested the affect on LD to photoreceptors and RPE. NAD+ levels cycle with a 24-h rhythm in mammals, which is affected by the feeding schedule. Therefore, we tested the affect of increasing NAD+ levels on LD by giving nicotinamide, inverting the feeding schedule, or using transgenic mice which overexpress cytoplasmic nicotinamide mononucleotide adenyl-transferase-1 (cytNMNAT1), an NAD+ synthetic enzyme. Zn2+ accumulation was also assessed in culture and in retinal sections. Retinas of light damaged animals were examined by OCT and plastic sectioning, and retinal NAD levels were measured. Day fed, or nicotinamide treated rats showed less NAD+ loss, and LD compared to night fed rats or untreated rats without changing the Zn2+ staining pattern. CytNMNAT1 showed less Zn2+ staining, NAD+ loss, and cell death after LD. In conclusion, intense light, Zn2+ and oxidative toxicities caused an increase in Zn2+, NAD+ loss, and cell death which were attenuated by NAD+ restoration. Therefore, NAD+ levels play a protective role in LD-induced death of photoreceptors and RPE cells. PMID:23274583

  10. Nicotinamide Enhances Repair of Arsenic and Ultraviolet Radiation-Induced DNA Damage in HaCaT Keratinocytes and Ex Vivo Human Skin

    PubMed Central

    Thompson, Benjamin C.; Halliday, Gary M.; Damian, Diona L.

    2015-01-01

    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. PMID:25658450

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

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

    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 observedmore » 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.« less

  12. Safety assessment of nicotinamide riboside, a form of vitamin B3.

    PubMed

    Conze, D B; Crespo-Barreto, J; Kruger, C L

    2016-01-20

    Nicotinamide riboside (NR) is a naturally occurring form of vitamin B 3 present in trace amounts in some foods. Like niacin, it has been shown to be a precursor in the biosynthesis of nicotinamide adenine dinucleotide (NAD+). The safety of Niagen™, a synthetic form of NR, was determined using a bacterial reverse mutagenesis assay (Ames), an in vitro chromosome aberration assay, an in vivo micronucleus assay, and acute, 14-day and 90-day rat toxicology studies. NR was not genotoxic. There was no mortality at an oral dose of 5000 mg/kg. Based on the results of a 14-day study, a 90-day study was performed comparing NR at 300, 1000, and 3000 mg/kg/day to an equimolar dose of nicotinamide at 1260 mg/kg/day as a positive control. Results from the study show that NR had a similar toxicity profile to nicotinamide at the highest dose tested. Target organs of toxicity were liver, kidney, ovaries, and testes. The lowest observed adverse effect level for NR was 1000 mg/kg/day, and the no observed adverse effect level was 300 mg/kg/day. © The Author(s) 2016.

  13. An efficient chemical synthesis of nicotinamide riboside (NAR) and analogues.

    PubMed

    Tanimori, Shinji; Ohta, Takeshi; Kirihata, Mitsunori

    2002-04-22

    A simple and efficient synthesis of nicotinamide riboside (NAR) 1 and derivatives 4 and 5 via trimethylsilyl trifluoromethanesulfonate (TMSOTf)-mediated N-glycosilation followed by spontaneous deacetylation by treating with methanol is reported.

  14. Thermochemical characteristics of nicotinamide protolytic equilibria in water-dimethylsulfoxide mixtures

    NASA Astrophysics Data System (ADS)

    Grazhdan, K. V.; Gamov, G. A.; Dushina, S. V.; Sharnin, V. A.

    2012-04-01

    The heat effects of nicotinamide protonation in water-dimethylsulfoxide (DMSO) solutions over the concentration range 0-0.75 DMSO mole fractions were determined calorimetrically at 25.00 ± 0.01°C and ionic strength 0.25 (NaClO4). Changes in the enthalpy of protonation as the content of DMSO increased were found to be described by an S-shaped curve. This curve shape was caused by the dynamics of reagent solvation contributions as the concentration of DMSO grew with the predominance of the nicotinamide solvation contribution.

  15. Targeting solid tumours with potassium channel activators. A return to fundamentals?

    PubMed

    Trechot, Philippe

    2014-01-01

    From a pharmacological point of view nicotinamide and minoxidil are potassium channel activators. Nicotinamide is used as a radiosensitizer in ARCON (accelerated radiotherapy combined with carbogen breathing and nicotinamide) therapeutic strategy with promising results but not confirmed so far. Minoxidil has never been considered by radiotherapists. Based from recent pathophysiological considerations we suggest a new perspective for the use of these two "old" molecules in order to target solid tumours. © 2014 Société Française de Pharmacologie et de Thérapeutique.

  16. Nicotinamide polymeric nanoemulsified systems: a quality-by-design case study for a sustained antimicrobial activity

    PubMed Central

    Zidan, Ahmed S; Ahmed, Osama AA; Aljaeid, Bader M

    2016-01-01

    Nicotinamide, the amide form of vitamin B3, was demonstrated to combat some of the antibiotic-resistant infections that are increasingly common around the world. The objective of this study was to thoroughly understand the formulation and process variabilities affecting the preparation of nicotinamide-loaded polymeric nanoemulsified particles. The quality target product profile and critical quality attributes of the proposed product were presented. Plackett–Burman screening design was employed to screen eight variables for their influences on the formulation’s critical characteristics. The formulations were prepared by an oil-in-water emulsification followed by solvent replacement. The prepared systems were characterized by entrapment capacity (EC), entrapment efficiency (EE), particle size, polydispersity index, zeta potential, transmission electron microscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, powder X-ray diffraction, in vitro drug release, and their antibacterial activity against bacterial scrums. EC, EE, particle size, polydispersity index, zeta potential, and percentage release in 24 hours were found to be in the range of 33.5%–68.8%, 53.1%–67.1%, 43.3–243.3 nm, 0.08–0.28, 9.5–53.3 mV, and 5.8%–22.4%, respectively. One-way analysis of variance and Pareto charts revealed that the experimental loadings of 2-hydroxypropyl-β-cyclodextrin and Eudragit® S100 were the most significant for their effects on nicotinamide EC and EE. Moreover, the polymeric nanoemulsified particles demonstrated a sustained release profile for nicotinamide. The Fourier transform infrared spectroscopy, differential scanning calorimetry, and X-ray diffraction demonstrated a significant interaction between the drug and 2-hydroxypropyl-β-cyclodextrin that might modulate the sustained release behavior. Furthermore, the formulations provided a sustained antibacterial activity that depended on nicotinamide-loading concentration, release rate, and incubation time. In conclusion, the study demonstrated the potential of polymeric nanoemulsified system to sustain the release and antibacterial activity of nicotinamide. PMID:27110111

  17. The use of nicotinamide in the prevention of type 1 diabetes.

    PubMed

    Elliott, R B; Pilcher, C C; Stewart, A; Fergusson, D; McGregor, M A

    1993-11-30

    Nicotinamide can protect the NOD mouse from diabetes if given early enough and in sufficient dose. The effect partly wanes with time. There is reduced islet inflammation. Similar protective effects can be demonstrated in quasi-experimental interventions in humans--both diabetes related and unrelated deemed at risk of developing diabetes by reason of having islet cell antibodies. Nicotinamide protects isolated islets in vitro from the toxicity of a number of agents, but only in doses that produce significant PARP inhibition, and increased intracellular levels of NAD. It is unlikely that the protective effect demonstrated in humans is due to significant PARP inhibition, as the levels of nicotinamide achieved with the doses used are too low. Other effects of the vitamin are more likely, e.g., increase in NAD pool size by de novo synthesis, or inhibition of free radical generation. The drug appears to be safe in the doses employed in humans.

  18. 5-((3-Amidobenzyl)oxy)nicotinamides as Sirtuin 2 Inhibitors.

    PubMed

    Ai, Teng; Wilson, Daniel J; More, Swati S; Xie, Jiashu; Chen, Liqiang

    2016-04-14

    Derived from our previously reported human sirtuin 2 (SIRT2) inhibitors that were based on a 5-aminonaphthalen-1-yloxy nicotinamide core structure, 5-((3-amidobenzyl)oxy)nicotinamides offered excellent activity against SIRT2 and high isozyme selectivity over SIRT1 and SIRT3. Selected compounds also exhibited generally favorable in vitro absorption, distribution, metabolism, and excretion properties. Kinetic studies revealed that a representative SIRT2 inhibitor acted competitively against both NAD(+) and the peptide substrate, an inhibitory modality that was supported by our computational study. More importantly, two selected compounds exhibited significant protection against α-synuclein aggregation-induced cytotoxicity in SH-SY5Y cells. Therefore, 5-((3-amidobenzyl)oxy)nicotinamides represent a new class of SIRT2 inhibitors that are attractive candidates for further lead optimization in our continued effort to explore selective inhibition of SIRT2 as a potential therapy for Parkinson's disease.

  19. 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

    PubMed Central

    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

  20. Phosphorylation of 3-deazaguanosine by nicotinamide riboside kinase in Chinese hamster ovary cells.

    PubMed

    Saunders, P P; Tan, M T; Spindler, C D; Robins, R K

    1989-12-01

    The growth inhibitory activity of 3-deazaguanosine toward a mutant line (TGR-3) of Chinese hamster ovary cells deficient in hypoxanthine-guanine phosphoribosyltransferase (EC 2.4.2.8) was substantially reversed by the simultaneous addition of nicotinamide riboside. The activities of most other ribonucleoside analogues tested were unaffected. The formation of cellular 3-deazaGMP and 3-deazaGTP from the ribonucleoside analogue, as measured by high-pressure liquid chromatography, was inhibited by the presence of nicotinamide riboside. The inhibition was dependent on concentration of 3-deazaguanosine and could also be demonstrated by following the metabolism of 3-deazaguanosine, labeled with 14C in the ribose moiety, to [14C]3-deazaGTP. In the presence of 100 microM nicotinamide riboside formation of the labeled triphosphate derivative of 3-deazaguanosine was undetectable. A 3-deazaguanosine phosphorylating activity was separated from other cellular kinases by DEAE-cellulose chromatography. Contaminating purine nucleoside phosphorylase (EC 2.4.2.1) was subsequently removed by sucrose density gradient centrifugation. The resulting enzyme preparation demonstrated the greatest activities with nicotinamide riboside and 3-deazaguanosine and, in addition, could also phosphorylate tiazofurin and guanosine to lesser, but significant, degrees. These and other observations suggest that 3-deazaguanosine, and perhaps other agents such as tiazofurin, may, at least in part, be phosphorylated by a nicotinamide ribonucleoside kinase in these cells. If so, it is possible that the activity of this agent in other types of cells in vivo could be dependent upon the presence of this enzyme and that it could be influenced by cellular concentrations of the natural pyridine nucleoside.

  1. Profiles of the biosynthesis and metabolism of pyridine nucleotides in potatoes (Solanum tuberosum L.).

    PubMed

    Katahira, Riko; Ashihara, Hiroshi

    2009-12-01

    As part of a research program on nucleotide metabolism in potato tubers (Solanum tuberosum L.), profiles of pyridine (nicotinamide) metabolism were examined based on the in situ metabolic fate of radio-labelled precursors and the in vitro activities of enzymes. In potato tubers, [(3)H]quinolinic acid, which is an intermediate of de novo pyridine nucleotide synthesis, and [(14)C]nicotinamide, a catabolite of NAD, were utilised for pyridine nucleotide synthesis. The in situ tracer experiments and in vitro enzyme assays suggest the operation of multiple pyridine nucleotide cycles. In addition to the previously proposed cycle consisting of seven metabolites, we found a new cycle that includes newly discovered nicotinamide riboside deaminase which is also functional in potato tubers. This cycle bypasses nicotinamide and nicotinic acid; it is NAD --> nicotinamide mononucleotide --> nicotinamide riboside --> nicotinic acid riboside --> nicotinic acid mononucleotide --> nicotinic acid adenine dinucleotide --> NAD. Degradation of the pyridine ring was extremely low in potato tubers. Nicotinic acid glucoside is formed from nicotinic acid in potato tubers. Comparative studies of [carboxyl-(14)C]nicotinic acid metabolism indicate that nicotinic acid is converted to nicotinic acid glucoside in all organs of potato plants. Trigonelline synthesis from [carboxyl-(14)C]nicotinic acid was also found. Conversion was greater in green parts of plants, such as leaves and stem, than in underground parts of potato plants. Nicotinic acid utilised for the biosynthesis of these conjugates seems to be derived not only from the pyridine nucleotide cycle, but also from the de novo synthesis of nicotinic acid mononucleotide.

  2. Nicotinamide and skin cancer chemoprevention: The jury is still out.

    PubMed

    Gilmore, Stephen J

    2018-02-01

    Following the publication of the results of a Phase III trial, the administration of oral nicotinamide has been widely advocated as effective in non-melanoma skin cancer chemoprevention in high-risk individuals. However, I performed a Bayesian analysis of the reported findings and show there is insufficient evidence to demonstrate its efficacy, highlighting the significant probability that the positive conclusions drawn will not be reproducible. Given the potential widespread use of oral nicotinamide, future position statements regarding its efficacy are likely to require higher standards of evidence. © 2017 The Australasian College of Dermatologists.

  3. Meat Intake and the Dose of Vitamin B3 – Nicotinamide: Cause of the Causes of Disease Transitions, Health Divides, and Health Futures?

    PubMed Central

    Hill, Lisa J; Williams, Adrian C

    2017-01-01

    Meat and vitamin B3 – 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 B3 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 B3 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. PMID:28579801

  4. The chemistry of nicotinamide adenine dinucleotide (NAD) analogues containing C-nucleosides related to nicotinamide riboside.

    PubMed

    Pankiewicz, Krzysztof W; Watanabe, Kyoichi A; Lesiak-Watanabe, Krystyna; Goldstein, Barry M; Jayaram, Hiremagalur N

    2002-04-01

    Oncolytic C-nucleosides, tiazofurin (2-beta-D-ribofuranosylthiazole-4-carboxamide) and benzamide riboside (3-beta-D-ribofuranosylbenzamide) are converted in cell into active metabolites thiazole-4-carboxamide- and benzamide adenine dinucleotide, TAD and BAD, respectively. TAD and BAD as NAD analogues were found to bind at the nicotinamide adenine dinucleotide (cofactor NAD) site of inosine monophosphate dehydrogenase (IMPDH), an important target in cancer treatment. The synthesis and evaluation of anticancer activity of a number of C-nucleosides related to tiazofurin and nicotinamide riboside then followed and are reviewed herein. Interestingly, pyridine C-nucleosides (such as C-nicotinamide riboside) are not metabolized into the corresponding NAD analogues in cell. Their conversion by chemical methods is described. As dinucleotides these compounds show inhibition of IMPDH in low micromolar level. Also, the synthesis of BAD in metabolically stable bis(phosphonate) form is discussed indicating the usefulness of such preformed inhibitors in drug development. Among tiazofurin analogues, Franchetti and Grifantini found, that the replacement of the sulfur by oxygen (as in oxazafurin) but not the removal of nitrogen (tiophenfurin) of the thiazole ring resulted in inactive compounds. The anti cancer activity of their synthetic dinucleotide analogues indicate that inactive compounds are not only poorly metabolized in cell but also are weak inhibitors of IMPDH as dinucleotides.

  5. Replicatively senescent human fibroblasts reveal a distinct intracellular metabolic profile with alterations in NAD+ and nicotinamide metabolism.

    PubMed

    James, Emma L; Lane, James A E; Michalek, Ryan D; Karoly, Edward D; Parkinson, E Kenneth

    2016-12-07

    Cellular senescence occurs by proliferative exhaustion (PEsen) or following multiple cellular stresses but had not previously been subject to detailed metabolomic analysis. Therefore, we compared PEsen fibroblasts with proliferating and transiently growth arrested controls using a combination of different mass spectroscopy techniques. PEsen cells showed many specific alterations in both the NAD+ de novo and salvage pathways including striking accumulations of nicotinamide mononucleotide (NMN) and nicotinamide riboside (NR) in the amidated salvage pathway despite no increase in nicotinamide phosphoribosyl transferase or in the NR transport protein, CD73. Extracellular nicotinate was depleted and metabolites of the deamidated salvage pathway were reduced but intracellular NAD+ and nicotinamide were nevertheless maintained. However, sirtuin 1 was downregulated and so the accumulation of NMN and NR was best explained by reduced flux through the amidated arm of the NAD+ salvage pathway due to reduced sirtuin activity. PEsen cells also showed evidence of increased redox homeostasis and upregulated pathways used to generate energy and cellular membranes; these included nucleotide catabolism, membrane lipid breakdown and increased creatine metabolism. Thus PEsen cells upregulate several different pathways to sustain their survival which may serve as pharmacological targets for the elimination of senescent cells in age-related disease.

  6. Replicatively senescent human fibroblasts reveal a distinct intracellular metabolic profile with alterations in NAD+ and nicotinamide metabolism

    PubMed Central

    James, Emma L.; Lane, James A. E.; Michalek, Ryan D.; Karoly, Edward D.; Parkinson, E. Kenneth

    2016-01-01

    Cellular senescence occurs by proliferative exhaustion (PEsen) or following multiple cellular stresses but had not previously been subject to detailed metabolomic analysis. Therefore, we compared PEsen fibroblasts with proliferating and transiently growth arrested controls using a combination of different mass spectroscopy techniques. PEsen cells showed many specific alterations in both the NAD+ de novo and salvage pathways including striking accumulations of nicotinamide mononucleotide (NMN) and nicotinamide riboside (NR) in the amidated salvage pathway despite no increase in nicotinamide phosphoribosyl transferase or in the NR transport protein, CD73. Extracellular nicotinate was depleted and metabolites of the deamidated salvage pathway were reduced but intracellular NAD+ and nicotinamide were nevertheless maintained. However, sirtuin 1 was downregulated and so the accumulation of NMN and NR was best explained by reduced flux through the amidated arm of the NAD+ salvage pathway due to reduced sirtuin activity. PEsen cells also showed evidence of increased redox homeostasis and upregulated pathways used to generate energy and cellular membranes; these included nucleotide catabolism, membrane lipid breakdown and increased creatine metabolism. Thus PEsen cells upregulate several different pathways to sustain their survival which may serve as pharmacological targets for the elimination of senescent cells in age-related disease. PMID:27924925

  7. Nicotinamide prevents the long-term effects of perinatal asphyxia on basal ganglia monoamine systems in the rat.

    PubMed

    Bustamante, D; Goiny, M; Aström, G; Gross, J; Andersson, K; Herrera-Marschitz, M

    2003-01-01

    Asphyxia during birth can cause gross brain damage, but also subtle perturbations expressed as biochemical or motor deficits with late onset in life. Thus, it has been shown that brain dopamine levels can be increased or decreased depending upon the severity of the insult, and the region where the levels are determined. In this study, perinatal asphyxia was evoked by immersing pup-containing uterus horns removed by hysterectomy in a water bath at 37 degrees C for various periods of time from 0 to 20 min. After the insult, the pups were delivered, given to surrogate mothers, treated with nicotinamide, further observed and finally, 4 weeks later, killed for monoamine biochemistry of tissue samples taken from substantia nigra, neostriatum and nucleus accumbens. The main effect of perinatal asphyxia was a decrease in dopamine and metabolite levels in nucleus accumbens, and a paradoxical increase in the substantia nigra. Nicotinamide (100 mg/kg i.p., once a day for 3 days, beginning 24 h after the perinatal asphyctic insult) prevented the effect of asphyxia in nucleus accumbens. Furthermore, striatal dopamine levels were increased by nicotinamide in asphyctic animals. No apparent changes were observed in substantia nigra. A prominent unexpected effect of perinatal asphyxia alone was on the levels of the metabolite of 5-hydroxytryptamine, 5-hydroxyindoleacetic acid (5-HIAA), which were increased in substantia nigra and decreased in both neostriatum and accumbens. However, nicotinamide increased 5-HIAA levels in all regions, which appeared to be related to the extent of the asphyctic insult. These results suggest that nicotinamide is a useful treatment against the long-term consequences produced by perinatal asphyxia on brain monoamine systems, and that there is a therapeutic window following the insult, providing a therapeutic opportunity to protect the brain.

  8. Nicotinamide Adenine Dinucleotide (NAD+) and Nicotinamide: Sex Differences in Cerebral Ischemia

    PubMed Central

    Siegel, Chad S.; McCullough, Louise D.

    2013-01-01

    Background Previous literature suggests that cell death pathways activated after cerebral ischemia differ between the sexes. While caspase-dependent mechanisms predominate in the female brain, caspase-independent cell death induced by activation of Poly (ADP-ribose) polymerase (PARP) predominates in the male brain. PARP-1 gene deletion decreases infarction volume in the male brain, but paradoxically increases damage in PARP-1 knockout females. Purpose This study examined stroke induced changes in NAD+, a key energy molecule involved in PARP-1 activation in both sexes. Methods Mice were subjected to Middle Cerebral Artery Occlusion and NAD+ levels were assessed. Caspase-3 activity and nuclear translocation was assessed 6 hours after ischemia. In additional cohorts, Nicotinamide (500mg/kg i.p.) a precursor of NAD+ or vehicle was administered and infarction volume was measured 24 hours after ischemia. Results Males have higher baseline NAD+ levels than females. Significant stroke-induced NAD+ depletion occurred in males and ovariectomized females but not in intact females. PARP-1 deletion prevented the stroke induced loss in NAD+ in males, but worsened NAD+ loss in PARP-1 deficient females. Preventing NAD+ loss with nicotinamide reduced infarct in wild-type males and PARP-1 knockout mice of both sexes, with no effect in WT females. Caspase-3 activity was significantly increased in PARP-1 knockout females compared to males and wild-type females, this was reversed with nicotinamide. Conclusions Sex differences exist in baseline and stroke-induced NAD+ levels. Nicotinamide protected males and PARP knockout mice, but had minimal effects in the wild-type female brain. This may be secondary to differences in energy metabolism between the sexes. PMID:23403179

  9. 21 CFR 172.315 - Nicotinamide-ascorbic acid complex.

    Code of Federal Regulations, 2010 CFR

    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...

  10. Temperature Dependence in the Terahertz Spectrum of Nicotinamide: Anharmonicity and Hydrogen-Bonded Network.

    PubMed

    Takahashi, Masae; Okamura, Nubuyuki; Fan, Xinyi; Shirakawa, Hitoshi; Minamide, Hiroaki

    2017-04-06

    We have investigated the terahertz-spectral property of nicotinamide focusing on the temperature dependence in the range of 14-300 K. We observed that almost all peaks in the terahertz spectrum of the nicotinamide crystal showed a remarkable shift with temperature, whereas the lowest-frequency peak at 34.8 cm -1 showed a negligible shift with temperature. By analyzing the terahertz spectrum with the dispersion-corrected density functional theory calculations, we found that the difference in the temperature dependence of the peak shift is well understood in terms of the presence/absence of stretching vibration of the intermolecular hydrogen bond in the mode and the change of cell parameters. The anharmonicity in the dissociation potential energy of very weak intermolecular hydrogen bonding causes the remarkable peak shift with temperature in the terahertz spectrum of nicotinamide. This finding suggests that the assignment and identification of peaks in the terahertz spectrum are systematically enabled by temperature-dependent measurements.

  11. Formulation and Solid State Characterization of Nicotinamide-based Co-crystals of Fenofibrate

    PubMed Central

    Shewale, Sheetal; Shete, A. S.; Doijad, R. C.; Kadam, S. S.; Patil, V. A.; Yadav, A. V.

    2015-01-01

    The present investigation deals with formulation of nicotinamide-based co-crystals of fenofibrate by different methods and solid-state characterization of the prepared co-crystals. Fenofibrate and nicotinamide as a coformer in 1:1 molar ratio were used to formulate molecular complexes by kneading, solution crystallization, antisolvent addition and solvent drop grinding methods. The prepared molecular complexes were characterized by powder X-ray diffractometry, differential scanning calorimetry, Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy and in vitro dissolution study. Considerable improvement in the dissolution rate of fenofibrate from optimized co-crystal formulation was due to an increased solubility that is attributed to the super saturation from the fine co-crystals is faster because of large specific surface area of small particles and prevention of phase transformation to pure fenofibrate. In vitro dissolution study showed that the formation of co-crystals improves the dissolution rate of fenofibrate. Nicotinamide forms the co-crystals with fenofibrate, theoretically and practically. PMID:26180279

  12. Application of a coupled enzyme assay to characterize nicotinamide riboside kinases.

    PubMed

    Dölle, Christian; Ziegler, Mathias

    2009-02-15

    The recently identified nicotinamide riboside kinases (Nrks) constitute a distinct pathway of nicotinamide adenine dinucleotide (NAD) biosynthesis. Here we present the combination of an established optical adenosine triphosphatase (ATPase) test, the pyruvate kinase/lactate dehydrogenase system, with the Nrk-catalyzed reaction to determine kinetic properties of these enzymes, in particular affinities for ATP. The assay allows variation of both nucleoside and phosphate donor substrates, thereby providing major advantages for the characterization of these enzymes. We confirm previously established kinetic parameters and identify differences in substrate selectivity between the two human Nrk isoforms. The proposed assay is inexpensive and may be applied for high-throughput screening.

  13. Hydrogen bonding interactions in nicotinamide Ionic Liquids: A comparative spectroscopic and DFT studies

    NASA Astrophysics Data System (ADS)

    Shukla, Madhulata

    2017-03-01

    Being biodegradable in nature nicotinamide based Ionic Liquids (ILs) are gaining much attention now a day. Nicotinamide iodide (i.e 1-methyl-3ethoxy carbonyl pyridinium iodide (mNicI)) and 1-methyl-3ethoxy carbonyl pyridinium trifilimide (mNicNTf2) new ILs has been synthesized and has been characterized using different spectroscopic techniques like NMR, UV visible and infrared spectroscopy. Theoretical studies have been performed on several nicotinamide ILs. Geometry and spectral features were further characterized by Density Functional Theory (DFT) calculation. NBO charge distribution and electrostatic potential diagram presents in depth knowledge about interactions between cation and anion. A comparative theoretical study between mNicI and its other analogues i. e 1-methyl-3 ethoxy carbonyl pyridinium chloride and bromide i. e mNicCl and mNicBr has also been performed. Csbnd H⋯X hydrogen bonding along with C⋯X interaction has been reported for the first time for the nicotinamide based ILs. C2sbnd H stretching frequency shifts to higher wavenumber with change to a lesser electronegative anion. mNicCl and mNicBr are expected to be solid in nature with the evidence from the red shift in stretching frequency as compared to mNicI. TD-DFT calculation of mNicI proved that pale yellow color of liquid is due to inherent transition from anion to cation.

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

    PubMed Central

    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

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

    PubMed Central

    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

  16. Increasing NAD synthesis in muscle via nicotinamide phosphoribosyltransferase is not sufficient to promote oxidative metabolism.

    PubMed

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

    2015-01-16

    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. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

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

    PubMed Central

    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

  18. Vitamins and aging: pathways to NAD+ synthesis.

    PubMed

    Denu, John M

    2007-05-04

    Recent genetic evidence reveals additional salvage pathways for NAD(+) synthesis. In this issue, Belenky et al. (2007) report that nicotinamide riboside, a new NAD(+) precursor, regulates Sir2 deacetylase activity and life span in yeast. The ability of nicotinamide riboside to enhance life span does not depend on calorie restriction.

  19. The Emergence of the Nicotinamide Riboside Kinases in the regulation of NAD+ Metabolism.

    PubMed

    Fletcher, Rachel S; Lavery, Gareth

    2018-05-30

    The concept of replenishing or elevating nicotinamide adenine dinucleotide (NAD+) availability to combat metabolic disease and ageing (described extensively in recent reviews [1, 2]) is an area of intense research. This has led to a need to define the endogenous regulatory pathways and mechanisms cell and tissues utilise to maximise NAD+ availability such that strategies to intervene in the clinical setting are able to be fully realised. This review discusses the importance of different salvage pathways involved in metabolising the vitamin B3 class of NAD+ precursor molecules, with a particular focus on the recently identified nicotinamide riboside kinase (NRK) pathway at both a tissue-specific and systemic level.

  20. Nicotinamide ribosyl uptake mutants in Haemophilus influenzae.

    PubMed

    Herbert, Mark; Sauer, Elizabeta; Smethurst, Graeme; Kraiss, Anita; Hilpert, Anna-Karina; Reidl, Joachim

    2003-09-01

    The gene for the nicotinamide riboside (NR) transporter (pnuC) was identified in Haemophilus influenzae. A pnuC mutant had only residual NR uptake and could survive in vitro with high concentrations of NR, but could not survive in vivo. PnuC may represent a target for the development of inhibitors for preventing H. influenzae disease.

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

    PubMed

    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.

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

    PubMed

    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.

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

    NASA Astrophysics Data System (ADS)

    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.

  4. A survey of synthetic nicotinamide cofactors in enzymatic processes.

    PubMed

    Paul, Caroline E; Hollmann, Frank

    2016-06-01

    Synthetic nicotinamide cofactors are analogues of the natural cofactors used by oxidoreductases as redox intermediates. Their ability to be fine-tuned makes these biomimetics an attractive alternative to the natural cofactors in terms of stability, reactivity, and cost. The following mini-review focuses on the current state of the art of those biomimetics in enzymatic processes.

  5. Nicotinamide Ribosyl Uptake Mutants in Haemophilus influenzae

    PubMed Central

    Herbert, Mark; Sauer, Elizabeta; Smethurst, Graeme; Kraiβ, Anita; Hilpert, Anna-Karina; Reidl, Joachim

    2003-01-01

    The gene for the nicotinamide riboside (NR) transporter (pnuC) was identified in Haemophilus influenzae. A pnuC mutant had only residual NR uptake and could survive in vitro with high concentrations of NR, but could not survive in vivo. PnuC may represent a target for the development of inhibitors for preventing H. influenzae disease. PMID:12933892

  6. Boosting NAD to spare hearing.

    PubMed

    Brenner, Charles

    2014-12-02

    Ex vivo experiments have strangely shown that inhibition or stimulation of NAD metabolism can be neuroprotective. In this issue of Cell Metabolism, Brown et al. (2014) demonstrate that cochlear NAD is diminished by deafening noise but protected by nicotinamide riboside or WldS mutation. Hearing protection by nicotinamide riboside depends on Sirt3. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Visfatin and cardio-cerebro-vascular disease.

    PubMed

    Wang, Pei; Vanhoutte, Paul M; Miao, Chao-Yu

    2012-01-01

    Nicotinamide phosphoribosyltransferase is the rate-limiting enzyme that catalyzes the first step in the biosynthesis of nicotinamide adenine dinucleotide from nicotinamide. This protein was originally cloned as a putative pre-B cell colony-enhancing factor and also found to be a visceral fat-derived adipokine (visfatin). As a multifunctional protein, visfatin plays an important role in immunity, metabolism, aging, inflammation, and responses to stress. Visfatin also participates in several pathophysiological processes contributing to cardio-cerebro-vascular diseases, including hypertension, atherosclerosis, ischemic heart disease, and ischemic stroke. However, whether visfatin is a friend or a foe in these diseases remains uncertain. This brief review focuses on the current understanding of the complex role of visfatin in the cardio-cerebro-vascular system under normal and pathophysiological conditions.

  8. Diabetic complications within the context of aging: Nicotinamide adenine dinucleotide redox, insulin C-peptide, sirtuin 1-liver kinase B1-adenosine monophosphate-activated protein kinase positive feedback and forkhead box O3.

    PubMed

    Ido, Yasuo

    2016-07-01

    Recent research in nutritional control of aging suggests that cytosolic increases in the reduced form of nicotinamide adenine dinucleotide and decreasing nicotinamide adenine dinucleotide metabolism plays a central role in controlling the longevity gene products sirtuin 1 (SIRT1), adenosine monophosphate-activated protein kinase (AMPK) and forkhead box O3 (FOXO3). High nutrition conditions, such as the diabetic milieu, increase the ratio of reduced to oxidized forms of cytosolic nicotinamide adenine dinucleotide through cascades including the polyol pathway. This redox change is associated with insulin resistance and the development of diabetic complications, and might be counteracted by insulin C-peptide. My research and others' suggest that the SIRT1-liver kinase B1-AMPK cascade creates positive feedback through nicotinamide adenine dinucleotide synthesis to help cells cope with metabolic stress. SIRT1 and AMPK can upregulate liver kinase B1 and FOXO3, key factors that help residential stem cells cope with oxidative stress. FOXO3 directly changes epigenetics around transcription start sites, maintaining the health of stem cells. 'Diabetic memory' is likely a result of epigenetic changes caused by high nutritional conditions, which disturb the quiescent state of residential stem cells and impair tissue repair. This could be prevented by restoring SIRT1-AMPK positive feedback through activating FOXO3. © 2016 The Author. Journal of Diabetes Investigation published by Asian Association for the Study of Diabetes (AASD) and John Wiley & Sons Australia, Ltd.

  9. Metabolomics Analysis of Metabolic Effects of Nicotinamide Phosphoribosyltransferase (NAMPT) Inhibition on Human Cancer Cells

    PubMed Central

    Tolstikov, Vladimir; Nikolayev, Alexander; Dong, Sucai; Zhao, Genshi; Kuo, Ming-Shang

    2014-01-01

    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. PMID:25486521

  10. Accessing non-natural reactivity by irradiating nicotinamide-dependent enzymes with light

    NASA Astrophysics Data System (ADS)

    Emmanuel, Megan A.; Greenberg, Norman R.; Oblinsky, Daniel G.; Hyster, Todd K.

    2016-12-01

    Enzymes are ideal for use in asymmetric catalysis by the chemical industry, because their chemical compositions can be tailored to a specific substrate and selectivity pattern while providing efficiencies and selectivities that surpass those of classical synthetic methods. However, enzymes are limited to reactions that are found in nature and, as such, facilitate fewer types of transformation than do other forms of catalysis. Thus, a longstanding challenge in the field of biologically mediated catalysis has been to develop enzymes with new catalytic functions. Here we describe a method for achieving catalytic promiscuity that uses the photoexcited state of nicotinamide co-factors (molecules that assist enzyme-mediated catalysis). Under irradiation with visible light, the nicotinamide-dependent enzyme known as ketoreductase can be transformed from a carbonyl reductase into an initiator of radical species and a chiral source of hydrogen atoms. We demonstrate this new reactivity through a highly enantioselective radical dehalogenation of lactones—a challenging transformation for small-molecule catalysts. Mechanistic experiments support the theory that a radical species acts as an intermediate in this reaction, with NADH and NADPH (the reduced forms of nicotinamide adenine nucleotide and nicotinamide adenine dinucleotide phosphate, respectively) serving as both a photoreductant and the source of hydrogen atoms. To our knowledge, this method represents the first example of photo-induced enzyme promiscuity, and highlights the potential for accessing new reactivity from existing enzymes simply by using the excited states of common biological co-factors. This represents a departure from existing light-driven biocatalytic techniques, which are typically explored in the context of co-factor regeneration.

  11. CD73 Protein as a Source of Extracellular Precursors for Sustained NAD+ Biosynthesis in FK866-treated Tumor Cells*

    PubMed Central

    Grozio, Alessia; Sociali, Giovanna; Sturla, Laura; Caffa, Irene; Soncini, Debora; Salis, Annalisa; Raffaelli, Nadia; De Flora, Antonio; Nencioni, Alessio; Bruzzone, Santina

    2013-01-01

    NAD+ is mainly synthesized in human cells via the “salvage” pathways starting from nicotinamide, nicotinic acid, or nicotinamide riboside (NR). The inhibition with FK866 of the enzyme nicotinamide phosphoribosyltransferase (NAMPT), catalyzing the first reaction in the “salvage” pathway from nicotinamide, showed potent antitumor activity in several preclinical models of solid and hematologic cancers. In the clinical studies performed with FK866, however, no tumor remission was observed. Here we demonstrate that low micromolar concentrations of extracellular NAD+ or NAD+ precursors, nicotinamide mononucleotide (NMN) and NR, can reverse the FK866-induced cell death, this representing a plausible explanation for the failure of NAMPT inhibition as an anti-cancer therapy. NMN is a substrate of both ectoenzymes CD38 and CD73, with generation of NAM and NR, respectively. In this study, we investigated the roles of CD38 and CD73 in providing ectocellular NAD+ precursors for NAD+ biosynthesis and in modulating cell susceptibility to FK866. By specifically silencing or overexpressing CD38 and CD73, we demonstrated that endogenous CD73 enables, whereas CD38 impairs, the conversion of extracellular NMN to NR as a precursor for intracellular NAD+ biosynthesis in human cells. Moreover, cell viability in FK866-treated cells supplemented with extracellular NMN was strongly reduced in tumor cells, upon pharmacological inhibition or specific down-regulation of CD73. Thus, our study suggests that genetic or pharmacologic interventions interfering with CD73 activity may prove useful to increase cancer cell sensitivity to NAMPT inhibitors. PMID:23880765

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

    PubMed

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

    2018-01-05

    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 molL -1 and 700μL 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 molL -1 and 2.8mL 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 R 2 higher than 0.96 for both nicotinamide and thiamine, at orders of magnitude 10 -7 and 10 -8 molL -1 , respectively. The nicotinamide content in a cosmetic gel sample was also quantified by direct analysis presenting R 2 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. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. NadN and e (P4) are essential for utilization of NAD and nicotinamide mononucleotide but not nicotinamide riboside in Haemophilus influenzae.

    PubMed

    Kemmer, G; Reilly, T J; Schmidt-Brauns, J; Zlotnik, G W; Green, B A; Fiske, M J; Herbert, M; Kraiss, A; Schlör, S; Smith, A; Reidl, J

    2001-07-01

    Haemophilus influenzae has an absolute requirement for NAD (factor V) because it lacks almost all the biosynthetic enzymes necessary for the de novo synthesis of that cofactor. Factor V can be provided as either nicotinamide adenosine dinucleotide (NAD), nicotinamide mononucleotide (NMN), or nicotinamide riboside (NR) in vitro, but little is known about the source or the mechanism of uptake of these substrates in vivo. As shown by us earlier, at least two gene products are involved in the uptake of NAD, the outer membrane lipoprotein e (P4), which has phosphatase activity and is encoded by hel, and a periplasmic NAD nucleotidase, encoded by nadN. It has also been observed that the latter gene product is essential for H. influenzae growth on media supplemented with NAD. In this report, we describe the functions and substrates of these two proteins as they act together in an NAD utilization pathway. Data are provided which indicate that NadN harbors not only NAD pyrophosphatase but also NMN 5'-nucleotidase activity. The e (P4) protein is also shown to have NMN 5'-nucleotidase activity, recognizing NMN as a substrate and releasing NR as its product. Insertion mutants of nadN or deletion and site-directed mutants of hel had attenuated growth and a reduced uptake phenotype when NMN served as substrate. A hel and nadN double mutant was only able to grow in the presence of NR, whereas no uptake of NMN was observed.

  14. NadN and e (P4) Are Essential for Utilization of NAD and Nicotinamide Mononucleotide but Not Nicotinamide Riboside in Haemophilus influenzae

    PubMed Central

    Kemmer, Gabriele; Reilly, Thomas J.; Schmidt-Brauns, Joachim; Zlotnik, Gary W.; Green, Bruce A.; Fiske, Michael J.; Herbert, Mark; Kraiß, Anita; Schlör, Stefan; Smith, Arnold; Reidl, Joachim

    2001-01-01

    Haemophilus influenzae has an absolute requirement for NAD (factor V) because it lacks almost all the biosynthetic enzymes necessary for the de novo synthesis of that cofactor. Factor V can be provided as either nicotinamide adenosine dinucleotide (NAD), nicotinamide mononucleotide (NMN), or nicotinamide riboside (NR) in vitro, but little is known about the source or the mechanism of uptake of these substrates in vivo. As shown by us earlier, at least two gene products are involved in the uptake of NAD, the outer membrane lipoprotein e (P4), which has phosphatase activity and is encoded by hel, and a periplasmic NAD nucleotidase, encoded by nadN. It has also been observed that the latter gene product is essential for H. influenzae growth on media supplemented with NAD. In this report, we describe the functions and substrates of these two proteins as they act together in an NAD utilization pathway. Data are provided which indicate that NadN harbors not only NAD pyrophosphatase but also NMN 5′-nucleotidase activity. The e (P4) protein is also shown to have NMN 5′-nucleotidase activity, recognizing NMN as a substrate and releasing NR as its product. Insertion mutants of nadN or deletion and site-directed mutants of hel had attenuated growth and a reduced uptake phenotype when NMN served as substrate. A hel and nadN double mutant was only able to grow in the presence of NR, whereas no uptake of NMN was observed. PMID:11395461

  15. Nicotinamide mononucleotide inhibits JNK activation to reverse Alzheimer disease.

    PubMed

    Yao, Zhiwen; Yang, Wenhao; Gao, Zhiqiang; Jia, Peng

    2017-04-24

    Amyloid-β (Aβ) oligomers have been accepted as major neurotoxic agents in the therapy of Alzheimer's disease (AD). It has been shown that the activity of nicotinamide adenine dinucleotide (NAD+) is related with the decline of Aβ toxicity in AD. Nicotinamide mononucleotide (NMN), the important precursor of NAD+, is produced during the reaction of nicotinamide phosphoribosyl transferase (Nampt). This study aimed to figure out the potential therapeutic effects of NMN and its underlying mechanisms in APPswe/PS1dE9 (AD-Tg) mice. We found that NMN gave rise to a substantial improvement in behavioral measures of cognitive impairments compared to control AD-Tg mice. In addition, NMN treatment significantly decreased β-amyloid production, amyloid plaque burden, synaptic loss, and inflammatory responses in transgenic animals. Mechanistically, NMN effectively controlled JNK activation. Furthermore, NMN potently progressed nonamyloidogenic amyloid precursor protein (APP) and suppressed amyloidogenic APP by mediating the expression of APP cleavage secretase in AD-Tg mice. Based on our findings, it was suggested that NMN substantially decreases multiple AD-associated pathological characteristically at least partially by the inhibition of JNK activation. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Nicotinamide adenine dinucleotide biosynthesis promotes liver regeneration

    PubMed Central

    Mukherjee, Sarmistha; Chellappa, Karthikeyani; Moffitt, Andrea; Ndungu, Joan; Dellinger, Ryan W.; Davis, James G.; Agarwal, Beamon; Baur, Joseph A.

    2016-01-01

    The regenerative capacity of the liver is essential for recovery from surgical resection or injuries induced by trauma or toxins. During liver regeneration, the concentration of nicotinamide adenine dinucleotide (NAD) falls, at least in part due to metabolic competition for precursors. To test whether NAD availability restricts the rate of liver regeneration, we supplied nicotinamide riboside (NR), an NAD precursor, in the drinking water of mice subjected to partial hepatectomy. NR increased DNA synthesis, mitotic index, and mass restoration in the regenerating livers. Intriguingly, NR also ameliorated the steatosis that normally accompanies liver regeneration. To distinguish the role of hepatocyte NAD levels from any systemic effects of NR, we generated mice overexpressing Nicotinamide phosphoribosyltransferase (Nampt), a rate-limiting enzyme for NAD synthesis, specifically in the liver. Nampt overexpressing mice were mildly hyperglycemic at baseline and, similarly to the mice treated with NR, exhibited enhanced liver regeneration and reduced steatosis following partial hepatectomy. Conversely, mice lacking Nampt in hepatocytes exhibited impaired regenerative capacity that was completely rescued by administering NR. Conclusion NAD availability is limiting during liver regeneration and supplementation with precursors such as NR may be therapeutic in settings of acute liver injury. PMID:27809334

  17. Donor-Acceptor Distance Sampling Enhances the Performance of "Better than Nature" Nicotinamide Coenzyme Biomimetics.

    PubMed

    Geddes, Alexander; Paul, Caroline E; Hay, Sam; Hollmann, Frank; Scrutton, Nigel S

    2016-09-07

    Understanding the mechanisms of enzymatic hydride transfer with nicotinamide coenzyme biomimetics (NCBs) is critical to enhancing the performance of nicotinamide coenzyme-dependent biocatalysts. Here the temperature dependence of kinetic isotope effects (KIEs) for hydride transfer between "better than nature" NCBs and several ene reductase biocatalysts is used to indicate transfer by quantum mechanical tunneling. A strong correlation between rate constants and temperature dependence of the KIE (ΔΔH(⧧)) for H/D transfer implies that faster reactions with NCBs are associated with enhanced donor-acceptor distance sampling. Our analysis provides the first mechanistic insight into how NCBs can outperform their natural counterparts and emphasizes the need to optimize donor-acceptor distance sampling to obtain high catalytic performance from H-transfer enzymes.

  18. Nicotinamide N-methyltransferase: more than a vitamin B3 clearance enzyme

    PubMed Central

    Pissios, Pavlos

    2017-01-01

    Nicotinamide N-methyltransferase (NNMT) was originally identified as the enzyme responsible for the methylation of nicotinamide (NAM), one of the forms of vitamin B3. Methylated NAM (MNAM) is eventually excreted from the body. Recent evidence has expanded the role of NNMT beyond clearance of excess vitamin B3. NNMT has been implicated in the regulation of multiple metabolic pathways in tissues such as the adipose tissue and liver, as well as cancer cells, through consumption of methyl donors and generation of active metabolites. This review examines recent findings regarding the function of NNMT in physiology and disease and highlights potential new avenues for therapeutic intervention. Finally, key gaps in our knowledge for this enzymatic system and future areas of investigation are discussed. PMID:28291578

  19. beta-1,2,3-Triazolyl-nucleosides as nicotinamide riboside mimics.

    PubMed

    Amigues, E J; Armstrong, E; Dvorakova, M; Migaud, M E; Huang, M

    2009-03-01

    The synthesis of a series of pyridine- and piperidine-substituted 1,2,3-triazolides linked to a riboside moiety is described. The presence of a triazolide substituent on the pyridine moiety permitted the facile reduction of the latter under mild hydrogenation conditions. These analogues were modelled as to define their similarity to nicotinamide riboside and quantify their ability to bind NAD-dependent protein deacetylases.

  20. Comparison of the effects of nicotinic acid and nicotinamide degradation on plasma betaine and choline levels.

    PubMed

    Sun, Wu-Ping; Zhai, Ming-Zhu; Li, Da; Zhou, Yiming; Chen, Na-Na; Guo, Ming; Zhou, Shi-Sheng

    2017-08-01

    The present study was to compare the effects of nicotinic acid and nicotinamide on the plasma methyl donors, choline and betaine. Thirty adult subjects were randomly divided into three groups of equal size, and orally received purified water (C group), nicotinic acid (300 mg, NA group) or nicotinamide (300 mg, NM group). Plasma nicotinamide, N 1 -methylnicotinamide, homocysteine, betaine and choline levels before and 1.5-h and 3-h post-dosing, plasma normetanephrine and metanephrine concentrations at 3-h post-dosing, and the urinary excretion of N 1 -methyl-2-pyridone-5-carboxamide during the test period were examined. The level of 3-h plasma nicotinamide, N 1 -methylnicotinamide, homocysteine, the urinary excretion of N 1 -methyl-2-pyridone-5-carboxamide and pulse pressure (PP) in the NM group was 221%, 3972%, 61%, 1728% and 21.2% higher than that of the control group (P < 0.01, except homocysteine and PP P < 0.05), while the 3-h plasma betaine, normetanephrine and metanephrine level in the NM group was 24.4%, 9.4% and 11.7% lower (P < 0.05, except betaine P < 0.01), without significant difference in choline levels. Similar but less pronounced changes were observed in the NA group, with a lower level of 3-h plasma N 1 -methylnicotinamide (1.90 ± 0.20 μmol/l vs. 3.62 ± 0.27 μmol/l, P < 0.01) and homocysteine (12.85 ± 1.39 μmol/l vs. 18.08 ± 1.02 μmol/l, P < 0.05) but a higher level of betaine (27.44 ± 0.71 μmol/l vs. 23.52 ± 0.61 μmol/l, P < 0.05) than that of the NM group. The degradation of nicotinamide consumes more betaine than that of nicotinic acid at identical doses. This difference should be taken into consideration in niacin fortification. Copyright © 2016 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

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

    PubMed

    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.

  2. 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

    PubMed Central

    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

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    French, Jarrod B.; Cen, Yana; Sauve, Anthony A.

    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. Themore » 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.« less

  4. Recycling nicotinamide. The transition-state structure of human nicotinamide phosphoribosyltransferase

    PubMed Central

    Burgos, Emmanuel S.; Vetticatt, Mathew J.; Schramm, Vern L.

    2013-01-01

    Human nicotinamide phosphoribosyltransferase (NAMPT) replenishes the NAD pool and controls the activities of sirtuins (SIRT), mono- and poly-(ADP-ribose) polymerases (PARP) and NAD nucleosidase (CD38). The nature of the enzymatic transition-state (TS) is central to understanding the function of NAMPT. We determined the TS structure for pyrophosphorolysis of nicotinamide mononucleotide (NMN) by kinetic isotope effects (KIEs). With the natural substrates, NMN and pyrophosphate (PPi), the intrinsic KIEs of [1′-14C], [1-15N], [1′-3H] and [2′-3H] are 1.047, 1.029, 1.154 and 1.093, respectively. A unique quantum computational approach was used for TS analysis that included structural elements of the catalytic site. Without constraints (e.g. imposed torsion angles), the theoretical and experimental data are in good agreement. The quantum-mechanical calculations incorporated a crucial catalytic site residue (D313), two magnesium atoms and coordinated water molecules. The transition state model predicts primary 14C, α-secondary 3H, β-secondary 3H and primary 15N KIE close to the experimental values. The analysis reveals significant ribocation character at the TS. The attacking PPi nucleophile is weakly interacting (rC-O = 2.60 Å) and the N-ribosidic C1′-N bond is highly elongated at the TS (rC-N = 2.35 Å), consistent with an ANDN mechanism. Together with the crystal structure of the NMN•PPi•Mg2•enzyme complex, the reaction coordinate is defined. The enzyme holds the nucleophile and leaving group in relatively fixed positions to create a reaction coordinate with C1′-anomeric migration from nicotinamide to the PPi. The transition state is reached by a 0.85 Å migration of C1′. PMID:23373462

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Smith, Brian C.; Anderson, Mark A.; Hoadley, Kelly A.

    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 nicotinaldehydemore » 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.« less

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Yun; Wang, Jing; Clinical Stem Cell Center, Peking University Third Hospital, 49 North Garden Road, Haidian District, Beijing 100191

    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 increasedmore » 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.« less

  7. Nicotinamide N‐methyltransferase expression decreases in iron overload, exacerbating toxicity in mouse hepatocytes

    PubMed Central

    Koppe, Tiago; Patchen, Bonnie; Cheng, Aaron; Bhasin, Manoj; Vulpe, Chris; Schwartz, Robert E.; Moreno‐Navarrete, Jose Maria; Fernandez‐Real, Jose Manuel

    2017-01-01

    Iron overload causes the generation of reactive oxygen species that can lead to lasting damage to the liver and other organs. The goal of this study was to identify genes that modify the toxicity of iron overload. We studied the effect of iron overload on the hepatic transcriptional and metabolomic profile in mouse models using a dietary model of iron overload and a genetic model, the hemojuvelin knockout mouse. We then evaluated the correlation of nicotinamide N‐methyltransferase (NNMT) expression with body iron stores in human patients and the effect of NNMT knockdown on gene expression and viability in primary mouse hepatocytes. We found that iron overload induced significant changes in the expression of genes and metabolites involved in glucose and nicotinamide metabolism and that NNMT, an enzyme that methylates nicotinamide and regulates hepatic glucose and cholesterol metabolism, is one of the most strongly down‐regulated genes in the liver in both genetic and dietary iron overload. We found that hepatic NNMT expression is inversely correlated with serum ferritin levels and serum transferrin saturation in patients who are obese, suggesting that body iron stores regulate human liver NNMT expression. Furthermore, we demonstrated that adenoviral knockdown of NNMT in primary mouse hepatocytes exacerbates iron‐induced hepatocyte toxicity and increases expression of transcriptional markers of oxidative and endoplasmic reticulum stress, while overexpression of NNMT partially reversed these effects. Conclusion: Iron overload alters glucose and nicotinamide transcriptional and metabolic pathways in mouse hepatocytes and decreases NNMT expression, while NNMT deficiency worsens the toxic effect of iron overload. For these reasons, NNMT may be a drug target for the prevention of iron‐induced hepatotoxicity. (Hepatology Communications 2017;1:803–815) PMID:29404495

  8. Identification of Novel Triazole-Based Nicotinamide Phosphoribosyltransferase (NAMPT) Inhibitors Endowed with Antiproliferative and Antiinflammatory Activity.

    PubMed

    Travelli, Cristina; Aprile, Silvio; Rahimian, Reza; Grolla, Ambra A; Rogati, Federica; Bertolotti, Mattia; Malagnino, Floriana; di Paola, Rosanna; Impellizzeri, Daniela; Fusco, Roberta; Mercalli, Valentina; Massarotti, Alberto; Stortini, Giorgio; Terrazzino, Salvatore; Del Grosso, Erika; Fakhfouri, Gohar; Troiani, Maria Pia; Alisi, Maria Alessandra; Grosa, Giorgio; Sorba, Giovanni; Canonico, Pier Luigi; Orsomando, Giuseppe; Cuzzocrea, Salvatore; Genazzani, Armando A; Galli, Ubaldina; Tron, Gian Cesare

    2017-03-09

    Nicotinamide phosphoribosyltransferase (NAMPT) is a key enzyme involved in the recycling of nicotinamide to maintain adequate NAD levels inside the cells. It has been postulated to be a pharmacological target, as it is overexpressed in cancer cells as well as in inflammatory diseases. We describe the synthesis and characterization of a novel class of one-digit nanomolar NAMPT inhibitors based on in vitro characterization. The most active compound tested, 30c, displayed activity in xenograft and allograft models, strengthening the potential of NAMPT inhibitors as antitumoral drugs. Furthermore, in the present contribution we describe the ability of 30c to significantly improve the outcome of colitis in mice. Given that this is the first report of an effect of NAMPT inhibitors in colitis, this result paves the way for novel applications for this class of compounds.

  9. Crystal engineering: co-crystals of cinnamic acid derivatives with a pyridyl derivative co-crystallizer.

    PubMed

    Lorenzo, Daniel A; Forrest, Sebastian J K; Sparkes, Hazel A

    2016-02-01

    A number of hydrogen-bonded co-crystals, consisting of a cinnamic acid derivative and a pyridyl co-crystallizer, have been synthesized and their properties investigated by X-ray diffraction. Samples were prepared by recrystallization or solvent drop grinding of trans-cinnamic acid (1), 4-methylcinnamic acid (2), 4-methoxy cinnamic acid (3) or 3,4-methoxy cinnamic acid (4), with 4,4-dipyridyl (A), iso-nicotinamide (B) or nicotinamide (C). The X-ray single-crystal structures of seven novel co-crystals, obtained through recrystallization, are examined and the hydrogen-bonding interactions discussed. Consistent hydrogen-bonding motifs were observed for samples prepared when using 4,4-dipyridyl (A) or iso-nicotinamide (B) as the co-crystallizing agent. Powder X-ray diffraction analysis of the samples prepared by solvent drop grinding suggests the formation of ten co-crystals.

  10. Chemo-enzymatic synthesis of isotopically labeled nicotinamide riboside.

    PubMed

    Tran, Ai; Yokose, Ryota; Cen, Yana

    2018-05-15

    As a cofactor for numerous reactions, NAD+ is found widely dispersed across many maps of cellular metabolism. This core redox role alone makes the biosynthesis of NAD+ of great interest. Recent studies have revealed new biological roles for NAD+ as a substrate for diverse enzymes that regulate a broad spectrum of key cellular tasks. These NAD+-consuming enzymes further highlight the importance of understanding NAD+ biosynthetic pathways. In this study, we developed a chemo-enzymatic synthesis of isotopically labeled NAD+ precursor, nicotinamide riboside (NR). The synthesis of NR isotopomers allowed us to unambiguously determine that NR is efficiently converted to NAD+ in the cellular environment independent of degradation to nicotinamide, and it is incorporated into NAD+ in its intact form. The versatile synthetic method along with the isotopically labeled NRs will provide powerful tools to further decipher the important yet complicated NAD+ metabolism.

  11. 1H NMR analysis of complexation of hydrotropic agents nicotinamide and caffeine with aromatic biologically active molecules in aqueous solution

    NASA Astrophysics Data System (ADS)

    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.

  12. Physicochemical characterization and structural evaluation of a specific 2:1 cocrystal of naproxen-nicotinamide.

    PubMed

    Ando, Shigeru; Kikuchi, Junko; Fujimura, Yuko; Ida, Yasuo; Higashi, Kenjirou; Moribe, Kunikazu; Yamamoto, Keiji

    2012-09-01

    Physicochemical characterization and structural evaluation of a 2:1 naproxen-nicotinamide cocrystal were performed. The 2:1 cocrystal showed rapid naproxen dissolution and less water vapor adsorption, indicating better pharmaceutical properties of naproxen. The unique 2:1 cocrystal formation was evaluated by solid-state nuclear magnetic resonance (NMR). The assignments of all H and (13) C peaks for naproxen and the cocrystal were performed using dipolar-insensitive nuclei enhanced by polarization transfer and (1) H-(13) C cross-polarization (CP)-heteronuclear correlation (HETCOR) NMR measurements. The (13) C chemical shift revealed that two naproxen molecules and one nicotinamide molecule existed in the asymmetric unit of the cocrystal. The (1) H chemical shifts indicated that the carboxylic group of the naproxen in the cocrystal was nonionized, and the CH-π interaction between naproxens was very strong. From the (1) H-(13) C CP-HETCOR NMR spectrum with contact time of 5 ms, two different synthons, carboxylic acid-amide and carboxylic acid-pyridine ring, were found between naproxen and nicotinamide. Single-crystal X-ray analysis, which supported the solid-state NMR results, clarified the geometry and intermolecular interactions in more detail. The structure is unique among pharmaceutical cocrystals because each carboxyl group of the two naproxens formed different intermolecular synthons. Copyright © 2012 Wiley Periodicals, Inc.

  13. Assimilation of Endogenous Nicotinamide Riboside Is Essential for Calorie Restriction-mediated Life Span Extension in Saccharomyces cerevisiae*

    PubMed Central

    Lu, Shu-Ping; Kato, Michiko; Lin, Su-Ju

    2009-01-01

    NAD+ (nicotinamide adenine dinucleotide) is an essential cofactor involved in various biological processes including calorie restriction-mediated life span extension. Administration of nicotinamide riboside (NmR) has been shown to ameliorate deficiencies related to aberrant NAD+ metabolism in both yeast and mammalian cells. However, the biological role of endogenous NmR remains unclear. Here we demonstrate that salvaging endogenous NmR is an integral part of NAD+ metabolism. A balanced NmR salvage cycle is essential for calorie restriction-induced life span extension and stress resistance in yeast. Our results also suggest that partitioning of the pyridine nucleotide flux between the classical salvage cycle and the NmR salvage branch might be modulated by the NAD+-dependent Sir2 deacetylase. Furthermore, two novel deamidation steps leading to nicotinic acid mononucleotide and nicotinic acid riboside production are also uncovered that further underscore the complexity and flexibility of NAD+ metabolism. In addition, utilization of extracellular nicotinamide mononucleotide requires prior conversion to NmR mediated by a periplasmic phosphatase Pho5. Conversion to NmR may thus represent a strategy for the transport and assimilation of large nonpermeable NAD+ precursors. Together, our studies provide a molecular basis for how NAD+ homeostasis factors confer metabolic flexibility. PMID:19416965

  14. Assimilation of endogenous nicotinamide riboside is essential for calorie restriction-mediated life span extension in Saccharomyces cerevisiae.

    PubMed

    Lu, Shu-Ping; Kato, Michiko; Lin, Su-Ju

    2009-06-19

    NAD(+) (nicotinamide adenine dinucleotide) is an essential cofactor involved in various biological processes including calorie restriction-mediated life span extension. Administration of nicotinamide riboside (NmR) has been shown to ameliorate deficiencies related to aberrant NAD(+) metabolism in both yeast and mammalian cells. However, the biological role of endogenous NmR remains unclear. Here we demonstrate that salvaging endogenous NmR is an integral part of NAD(+) metabolism. A balanced NmR salvage cycle is essential for calorie restriction-induced life span extension and stress resistance in yeast. Our results also suggest that partitioning of the pyridine nucleotide flux between the classical salvage cycle and the NmR salvage branch might be modulated by the NAD(+)-dependent Sir2 deacetylase. Furthermore, two novel deamidation steps leading to nicotinic acid mononucleotide and nicotinic acid riboside production are also uncovered that further underscore the complexity and flexibility of NAD(+) metabolism. In addition, utilization of extracellular nicotinamide mononucleotide requires prior conversion to NmR mediated by a periplasmic phosphatase Pho5. Conversion to NmR may thus represent a strategy for the transport and assimilation of large nonpermeable NAD(+) precursors. Together, our studies provide a molecular basis for how NAD(+) homeostasis factors confer metabolic flexibility.

  15. Nicotinamide riboside, a form of vitamin B3, protects against excitotoxicity-induced axonal degeneration.

    PubMed

    Vaur, Pauline; Brugg, Bernard; Mericskay, Mathias; Li, Zhenlin; Schmidt, Mark S; Vivien, Denis; Orset, Cyrille; Jacotot, Etienne; Brenner, Charles; Duplus, Eric

    2017-12-01

    NAD + depletion is a common phenomenon in neurodegenerative pathologies. Excitotoxicity occurs in multiple neurologic disorders and NAD + was shown to prevent neuronal degeneration in this process through mechanisms that remained to be determined. The activity of nicotinamide riboside (NR) in neuroprotective models and the recent description of extracellular conversion of NAD + to NR prompted us to probe the effects of NAD + and NR in protection against excitotoxicity. Here, we show that intracortical administration of NR but not NAD + reduces brain damage induced by NMDA injection. Using cortical neurons, we found that provision of extracellular NR delays NMDA-induced axonal degeneration (AxD) much more strongly than extracellular NAD + Moreover, the stronger effect of NR compared to NAD + depends of axonal stress since in AxD induced by pharmacological inhibition of nicotinamide salvage, both NAD + and NR prevent neuronal death and AxD in a manner that depends on internalization of NR. Taken together, our findings demonstrate that NR is a better neuroprotective agent than NAD + in excitotoxicity-induced AxD and that axonal protection involves defending intracellular NAD + homeostasis.-Vaur, P., Brugg, B., Mericskay, M., Li, Z., Schmidt, M. S., Vivien, D., Orset, C., Jacotot, E., Brenner, C., Duplus, E. Nicotinamide riboside, a form of vitamin B 3 , protects against excitotoxicity-induced axonal degeneration. © FASEB.

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

    NASA Astrophysics Data System (ADS)

    Saraydin, D.; Karadağ, E.; Çaldiran, Y.; Güven, O.

    2001-02-01

    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.

  17. P7C3 neuroprotective chemicals function by activating the rate-limiting enzyme in NAD salvage.

    PubMed

    Wang, Gelin; Han, Ting; Nijhawan, Deepak; Theodoropoulos, Pano; Naidoo, Jacinth; Yadavalli, Sivaramakrishnan; Mirzaei, Hamid; Pieper, Andrew A; Ready, Joseph M; McKnight, Steven L

    2014-09-11

    The P7C3 class of aminopropyl carbazole chemicals fosters the survival of neurons in a variety of rodent models of neurodegeneration or nerve cell injury. To uncover its mechanism of action, an active derivative of P7C3 was modified to contain both a benzophenone for photocrosslinking and an alkyne for CLICK chemistry. This derivative was found to bind nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme involved in the conversion of nicotinamide into nicotinamide adenine dinucleotide (NAD). Administration of active P7C3 chemicals to cells treated with doxorubicin, which induces NAD depletion, led to a rebound in intracellular levels of NAD and concomitant protection from doxorubicin-mediated toxicity. Active P7C3 variants likewise enhanced the activity of the purified NAMPT enzyme, providing further evidence that they act by increasing NAD levels through its NAMPT-mediated salvage. Copyright © 2014 Elsevier Inc. All rights reserved.

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

    PubMed

    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.

  19. Chronic nicotinamide riboside supplementation is well-tolerated and elevates NAD+ in healthy middle-aged and older adults.

    PubMed

    Martens, Christopher R; Denman, Blair A; Mazzo, Melissa R; Armstrong, Michael L; Reisdorph, Nichole; McQueen, Matthew B; Chonchol, Michel; Seals, Douglas R

    2018-03-29

    Nicotinamide adenine dinucleotide (NAD + ) has emerged as a critical co-substrate for enzymes involved in the beneficial effects of regular calorie restriction on healthspan. As such, the use of NAD + precursors to augment NAD + bioavailability has been proposed as a strategy for improving cardiovascular and other physiological functions with aging in humans. Here we provide the evidence in a 2 × 6-week randomized, double-blind, placebo-controlled, crossover clinical trial that chronic supplementation with the NAD + precursor vitamin, nicotinamide riboside (NR), is well tolerated and effectively stimulates NAD + metabolism in healthy middle-aged and older adults. Our results also provide initial insight into the effects of chronic NR supplementation on physiological function in humans, and suggest that, in particular, future clinical trials should further assess the potential benefits of NR for reducing blood pressure and arterial stiffness in this group.

  20. Nicotinamide riboside is uniquely and orally bioavailable in mice and humans.

    PubMed

    Trammell, Samuel A J; Schmidt, Mark S; Weidemann, Benjamin J; Redpath, Philip; Jaksch, Frank; Dellinger, Ryan W; Li, Zhonggang; Abel, E Dale; Migaud, Marie E; Brenner, Charles

    2016-10-10

    Nicotinamide riboside (NR) is in wide use as an NAD + precursor vitamin. Here we determine the time and dose-dependent effects of NR on blood NAD + metabolism in humans. We report that human blood NAD + can rise as much as 2.7-fold with a single oral dose of NR in a pilot study of one individual, and that oral NR elevates mouse hepatic NAD + with distinct and superior pharmacokinetics to those of nicotinic acid and nicotinamide. We further show that single doses of 100, 300 and 1,000 mg of NR produce dose-dependent increases in the blood NAD + metabolome in the first clinical trial of NR pharmacokinetics in humans. We also report that nicotinic acid adenine dinucleotide (NAAD), which was not thought to be en route for the conversion of NR to NAD + , is formed from NR and discover that the rise in NAAD is a highly sensitive biomarker of effective NAD + repletion.

  1. Crystal structure of human nicotinamide riboside kinase.

    PubMed

    Khan, Javed A; Xiang, Song; Tong, Liang

    2007-08-01

    Nicotinamide riboside kinase (NRK) has an important role in the biosynthesis of NAD(+) as well as the activation of tiazofurin and other NR analogs for anticancer therapy. NRK belongs to the deoxynucleoside kinase and nucleoside monophosphate (NMP) kinase superfamily, although the degree of sequence conservation is very low. We report here the crystal structures of human NRK1 in a binary complex with the reaction product nicotinamide mononucleotide (NMN) at 1.5 A resolution and in a ternary complex with ADP and tiazofurin at 2.7 A resolution. The active site is located in a groove between the central parallel beta sheet core and the LID and NMP-binding domains. The hydroxyl groups on the ribose of NR are recognized by Asp56 and Arg129, and Asp36 is the general base of the enzyme. Mutation of residues in the active site can abolish the catalytic activity of the enzyme, confirming the structural observations.

  2. Secondary NAD+ deficiency in the inherited defect of glutamine synthetase.

    PubMed

    Hu, Liyan; Ibrahim, Khalid; Stucki, Martin; Frapolli, Michele; Shahbeck, Noora; Chaudhry, Farrukh A; Görg, Boris; Häussinger, Dieter; Penberthy, W Todd; Ben-Omran, Tawfeg; Häberle, Johannes

    2015-11-01

    Glutamine synthetase (GS) deficiency is an ultra-rare inborn error of amino acid metabolism that has been described in only three patients so far. The disease is characterized by neonatal onset of severe encephalopathy, low levels of glutamine in blood and cerebrospinal fluid, chronic moderate hyperammonemia, and an overall poor prognosis in the absence of an effective treatment. Recently, enteral glutamine supplementation was shown to be a safe and effective therapy for this disease but there are no data available on the long-term effects of this intervention. The amino acid glutamine, severely lacking in this disorder, is central to many metabolic pathways in the human organism and is involved in the synthesis of nicotinamide adenine dinucleotide (NAD(+)) starting from tryptophan or niacin as nicotinate, but not nicotinamide. Using fibroblasts, leukocytes, and immortalized peripheral blood stem cells (PBSC) from a patient carrying a GLUL gene point mutation associated with impaired GS activity, we tested whether glutamine deficiency in this patient results in NAD(+) depletion and whether it can be rescued by supplementation with glutamine, nicotinamide or nicotinate. The present study shows that congenital GS deficiency is associated with NAD(+) depletion in fibroblasts, leukocytes and PBSC, which may contribute to the severe clinical phenotype of the disease. Furthermore, it shows that NAD(+) depletion can be rescued by nicotinamide supplementation in fibroblasts and leukocytes, which may open up potential therapeutic options for the treatment of this disorder.

  3. Nicotinamide mononucleotide inhibits post-ischemic NAD(+) degradation and dramatically ameliorates brain damage following global cerebral ischemia.

    PubMed

    Park, Ji H; Long, Aaron; Owens, Katrina; Kristian, Tibor

    2016-11-01

    Nicotinamide adenine dinucleotide (NAD(+)) is an essential cofactor for multiple cellular metabolic reactions and has a central role in energy production. Brain ischemia depletes NAD(+) pools leading to bioenergetics failure and cell death. Nicotinamide mononucleotide (NMN) is utilized by the NAD(+) salvage pathway enzyme, nicotinamide adenylyltransferase (Nmnat) to generate NAD(+). Therefore, we examined whether NMN could protect against ischemic brain damage. Mice were subjected to transient forebrain ischemia and treated with NMN or vehicle at the start of reperfusion or 30min after the ischemic insult. At 2, 4, and 24h of recovery, the proteins poly-ADP-ribosylation (PAR), hippocampal NAD(+) levels, and expression levels of NAD(+) salvage pathway enzymes were determined. Furthermore, animal's neurologic outcome and hippocampal CA1 neuronal death was assessed after six days of reperfusion. NMN (62.5mg/kg) dramatically ameliorated the hippocampal CA1 injury and significantly improved the neurological outcome. Additionally, the post-ischemic NMN treatment prevented the increase in PAR formation and NAD(+) catabolism. Since the NMN administration did not affect animal's temperature, blood gases or regional cerebral blood flow during recovery, the protective effect was not a result of altered reperfusion conditions. These data suggest that administration of NMN at a proper dosage has a strong protective effect against ischemic brain injury. Published by Elsevier Inc.

  4. Synthesis, characterization, crystal structure and antimicrobial studies of a novel Cu(II) complex based on itaconic acid and nicotinamide

    NASA Astrophysics Data System (ADS)

    Tella, Adedibu C.; Owalude, Samson O.; Ajibade, Peter A.; Simon, Nzikahyel; Olatunji, Sunday J.; Abdelbaky, Mohammed S. M.; Garcia-Granda, Santiago

    2016-12-01

    A novel complex was synthesized from Cu(II), nicotinamide and itaconic acid and is formulated as [Cu(C5H4O4)2(C6H6N2O)2(H2O)2·2(H2O)] (1). The compound was characterized by elemental analysis, FTIR spectroscopy, UV-Vis and single crystal X-ray diffraction. The complex crystallizes in the triclinic P-1 space group, with a = 7.5111(2) Å, b = 9.8529(3) Å, c = 10.5118(4) Å, α = 116.244(3)°, β = 90.291(3)°, γ = 103.335(3)°, V = 673.81(4) Å3, Z = 1.The octahedral geometry around the copper(II) ion is of the form CuN2O4 consisting of two molecules of nicotinamide acting as monodentate ligand through the nitrogen atoms, two molecules itaconate ligand and two coordinated water molecules each coordinating through the oxygen atoms. The structure of 1 showed infinite chains build up linking the molecules together via strong Osbnd H⋯O and Nsbnd H⋯O intermolecular hydrogen bonds generating a two dimensional network sheet along c axis. The antimicrobial study of the synthesized complex 1 was investigated and showed higher antibacterial activity against all the organisms comparing with Copper(II) nicotinamide 2 and Copper(II) itaconate 3.

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

    PubMed

    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.

  6. Toxicity of chemically generated nitric oxide towards pancreatic islet cells can be prevented by nicotinamide

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kallmann, B.; Burkart, V.; Kolb, H.

    1992-01-01

    Previous studies have indicated that nitric oxide is involved in the lysis of pancreatic islet cells by inflammatory macrophages. Here the authors show that the incubation of islet cells with chemical NO-donors leads to cell lysis in a concentration and time dependent way. Islet cell death could be prevented by nicotinamide and 3-aminobenzamide, which are known to inhibit ADP-ribosylation, while several scavengers of oxygen radicals, N-acetylcysteine, dihydrolipoic acid, dimethylthiourea and citiolone, provided no protection.

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Curtin, Michael L.; Heyman, H. Robin; Clark, Richard F.

    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.

  8. NAD(P)H-Independent Asymmetric C=C Bond Reduction Catalyzed by Ene Reductases by Using Artificial Co-substrates as the Hydrogen Donor

    PubMed Central

    Winkler, Christoph K; Clay, Dorina; Entner, Marcello; Plank, Markus; Faber, Kurt

    2014-01-01

    To develop a nicotinamide-independent single flavoenzyme system for the asymmetric bioreduction of C=C bonds, four types of hydrogen donor, encompassing more than 50 candidates, were investigated. Six highly potent, cheap, and commercially available co-substrates were identified that (under the optimized conditions) resulted in conversions and enantioselectivities comparable with, or even superior to, those obtained with traditional two-enzyme nicotinamide adenine dinucleotide phosphate (NAD(P)H)-recycling systems. PMID:24382795

  9. Semisynthetic biosensors for mapping cellular concentrations of nicotinamide adenine dinucleotides.

    PubMed

    Sallin, Olivier; Reymond, Luc; Gondrand, Corentin; Raith, Fabio; Koch, Birgit; Johnsson, Kai

    2018-05-29

    We introduce a new class of semisynthetic fluorescent biosensors for the quantification of free nicotinamide adenine dinucleotide (NAD + ) and ratios of reduced to oxidized nicotinamide adenine dinucleotide phosphate (NADPH/NADP + ) in live cells. Sensing is based on controlling the spatial proximity of two synthetic fluorophores by binding of NAD(P) to the protein component of the sensor. The sensors possess a large dynamic range, can be excited at long wavelengths, are pH-insensitive, have tunable response range and can be localized in different organelles. Ratios of free NADPH/NADP + are found to be higher in mitochondria compared to those found in the nucleus and the cytosol. By recording free NADPH/NADP + ratios in response to changes in environmental conditions, we observe how cells can react to such changes by adapting metabolic fluxes. Finally, we demonstrate how a comparison of the effect of drugs on cellular NAD(P) levels can be used to probe mechanisms of action. © 2018, Sallin et al.

  10. Antidiabetic and hypolipidemic effects of Dorema aucheri hydroalcoholic leave extract in streptozotocin-nicotinamide induced type 2 diabetes in male rats

    PubMed Central

    Ahangarpour, Akram; Zamaneh, Hossein Teymuri; Jabari, Ayob; Nia, Hamid Malekshahi; Heidari, Hamid

    2014-01-01

    Objective(s): The present study investigated the antidiabetic and hypolipidemic properties of Dorema aucheri leave hydroalcoholic extract in nicotinamide-streptozotocin induced type 2 diabetic rats. Materials and Methods: nicotinamide/streptozotocin-induced diabetic rats were supplemented orally with three different doses of D. aucheri (100, 200 and 400 mg/kg BW) or glibenclamide (0.25 mg/kg) for 4 weeks. Ultimately, blood of animals has taken and glucose, insulin, lipid profiles, SGPT, alkaline phosphatase, SGOT, leptin levels were assayed. Results: D. aucheri has highly significant blood glucose lowering effect. Administration of the extract to diabetic rats resulted in a remarkable change in serum lipid profiles, insulin and leptin levels relative to diabetic group. Also the extract reversed back the serum levels of SGPT, alkaline phosphatase and SGOT to near normal in treated diabetic rats. Conclusion: D. aucheri could be useful in treatment of diabetes. Moderate dose of D. aucheri (200 mg/kg) was more effective than the others. PMID:25729552

  11. Crystal Structure of Human Nicotinamide Riboside Kinase

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Khan,J.; Xiang, S.; Tong, L.

    2007-01-01

    Nicotinamide riboside kinase (NRK) has an important role in the biosynthesis of NAD{sup +} as well as the activation of tiazofurin and other NR analogs for anticancer therapy. NRK belongs to the deoxynucleoside kinase and nucleoside monophosphate (NMP) kinase superfamily, although the degree of sequence conservation is very low. We report here the crystal structures of human NRK1 in a binary complex with the reaction product nicotinamide mononucleotide (NMN) at 1.5 {angstrom} resolution and in a ternary complex with ADP and tiazofurin at 2.7 {angstrom} resolution. The active site is located in a groove between the central parallel {beta} sheetmore » core and the LID and NMP-binding domains. The hydroxyl groups on the ribose of NR are recognized by Asp56 and Arg129, and Asp36 is the general base of the enzyme. Mutation of residues in the active site can abolish the catalytic activity of the enzyme, confirming the structural observations.« less

  12. Activation of SIRT3 by the NAD⁺ precursor nicotinamide riboside protects from noise-induced hearing loss.

    PubMed

    Brown, Kevin D; Maqsood, Sadia; Huang, Jing-Yi; Pan, Yong; Harkcom, William; Li, Wei; Sauve, Anthony; Verdin, Eric; Jaffrey, Samie R

    2014-12-02

    Intense noise exposure causes hearing loss by inducing degeneration of spiral ganglia neurites that innervate cochlear hair cells. Nicotinamide adenine dinucleotide (NAD(+)) exhibits axon-protective effects in cultured neurons; however, its ability to block degeneration in vivo has been difficult to establish due to its poor cell permeability and serum instability. Here, we describe a strategy to increase cochlear NAD(+) levels in mice by administering nicotinamide riboside (NR), a recently described NAD(+) precursor. We find that administration of NR, even after noise exposure, prevents noise-induced hearing loss (NIHL) and spiral ganglia neurite degeneration. These effects are mediated by the NAD(+)-dependent mitochondrial sirtuin, SIRT3, since SIRT3-overexpressing mice are resistant to NIHL and SIRT3 deletion abrogates the protective effects of NR and expression of NAD(+) biosynthetic enzymes. These findings reveal that administration of NR activates a NAD(+)-SIRT3 pathway that reduces neurite degeneration caused by noise exposure. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. NAD+ repletion improves muscle function in muscular dystrophy and counters global PARylation

    PubMed Central

    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

    2017-01-01

    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. PMID:27798264

  14. Synthesis and crystal structure of catena-bis(nicotinamide)aqua({mu}-phthalato)copper(II) hemihydrate

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sadikov, G. G., E-mail: sadgg@igic.ras.ru; Koksharova, T. V.; Antsyshkina, A. S.

    2008-07-15

    The copper(II) phthalate complex with nicotinamide [CuL{sub 2}({mu}-Pht)(H{sub 2}O)] . 0.5H{sub 2}O(I) (where L is nicotinamide and Pht{sup 2-} is an anion of phthalic acid) is synthesized and investigated using IR spectroscopy and X-ray diffraction. The crystals of compound I are monoclinic, a = 13.368(2) A, b = 7.891(3) A, c = 20.480(2) A, {beta} = 108.69(2){sup o}, Z = 4, and space group P2{sub 1}/c. The structural units of crystal I are linear chains formed by bridging phthalate anions and crystallization water molecules. The copper atom is coordinated by two pyridine nitrogen atoms of two nicotinamide ligands (Cu-N, 2.001more » and 2.045 A), two oxygen atoms of different phthalate anions (Cu-O, 1.964 and 2.235 A), and the oxygen atom of the H{sub 2} O molecule (Cu-O, 2.014 A). The coordination polyhedron of the copper atom is completed to an elongated (4 + 1 + 1) tetragonal bipyramid by the second (chelating) oxygen atom of the carboxyl group (Cu-O, 2.587 A), which is one of the anions of phthalic acid. The linear polymer molecules are joined into complex macromolecular dimers with the closest internal contacts of the specific type. The macromolecular dimers are the main supramolecular ensembles of the crystal structure.« less

  15. Novel assay for simultaneous measurement of pyridine mononucleotides synthesizing activities allows dissection of the NAD(+) biosynthetic machinery in mammalian cells.

    PubMed

    Zamporlini, Federica; Ruggieri, Silverio; Mazzola, Francesca; Amici, Adolfo; Orsomando, Giuseppe; Raffaelli, Nadia

    2014-11-01

    The redox coenzyme NAD(+) is also a rate-limiting co-substrate for several enzymes that consume the molecule, thus rendering its continuous re-synthesis indispensable. NAD(+) biosynthesis has emerged as a therapeutic target due to the relevance of NAD(+) -consuming reactions in complex intracellular signaling networks whose alteration leads to many neurologic and metabolic disorders. Distinct metabolic routes, starting from various precursors, are known to support NAD(+) biosynthesis with tissue/cell-specific efficiencies, probably reflecting differential expression of the corresponding rate-limiting enzymes, i.e. nicotinamide phosphoribosyltransferase, quinolinate phosphoribosyltransferase, nicotinate phosphoribosyltransferase and nicotinamide riboside kinase. Understanding the contribution of these enzymes to NAD(+) levels depending on the tissue/cell type and metabolic status is necessary for the rational design of therapeutic strategies aimed at modulating NAD(+) availability. Here we report a simple, fast and sensitive coupled fluorometric assay that enables simultaneous determination of the four activities in whole-cell extracts and biological fluids. Its application to extracts from various mouse tissues, human cell lines and plasma yielded for the first time an overall picture of the tissue/cell-specific distribution of the activities of the various enzymes. The screening enabled us to gather novel findings, including (a) the presence of quinolinate phosphoribosyltransferase and nicotinamide riboside kinase in all examined tissues/cell lines, indicating that quinolinate and nicotinamide riboside are relevant NAD(+) precursors, and (b) the unexpected occurrence of nicotinate phosphoribosyltransferase in human plasma. © 2014 FEBS.

  16. Niacin activates the G protein estrogen receptor (GPER)-mediated signalling.

    PubMed

    Santolla, Maria Francesca; De Francesco, Ernestina Marianna; Lappano, Rosamaria; Rosano, Camillo; Abonante, Sergio; Maggiolini, Marcello

    2014-07-01

    Nicotinic acid, also known as niacin, is the water soluble vitamin B3 used for decades for the treatment of dyslipidemic diseases. Its action is mainly mediated by the G protein-coupled receptor (GPR) 109A; however, certain regulatory effects on lipid levels occur in a GPR109A-independent manner. The amide form of nicotinic acid, named nicotinamide, acts as a vitamin although neither activates the GPR109A nor exhibits the pharmacological properties of nicotinic acid. In the present study, we demonstrate for the first time that nicotinic acid and nicotinamide bind to and activate the GPER-mediated signalling in breast cancer cells and cancer-associated fibroblasts (CAFs). In particular, we show that both molecules are able to promote the up-regulation of well established GPER target genes through the EGFR/ERK transduction pathway. As a biological counterpart, nicotinic acid and nicotinamide induce proliferative and migratory effects in breast cancer cells and CAFs in a GPER-dependent fashion. Moreover, nicotinic acid prevents the up-regulation of ICAM-1 triggered by the pro-inflammatory cytokine TNF-α and stimulates the formation of endothelial tubes through GPER in HUVECs. Together, our findings concerning the agonist activity for GPER displayed by both nicotinic acid and nicotinamide broaden the mechanisms involved in the biological action of these molecules and further support the potential of a ligand to induce different responses mediated in a promiscuous manner by distinct GPCRs. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Glutamate Dehydrogenase from Apodachlya (Oomycetes) 1

    PubMed Central

    Price, Jeffrey S.; Gleason, Frank H.

    1972-01-01

    A glutamate dehydrogenase specific for nicotinamide-adenine-dinucleotide has been purified 50-fold from Apodachlya brachynema (Leptomitales). Certain physical, chemical, and kinetic properties of this enzyme have been studied, particularly specificity for coenzymes and substrates. With glucose as the sole carbon source, the synthesis of glutamate dehydrogenase was repressed, whereas glutamate, proline, alanine, or ornithine plus aspartate as sole carbon sources induced synthesis of the enzyme. These data indicate that the function of this enzyme is primarily degradative, although there is no evidence for a nicotinamide-adenine-dinucleotide-phosphate-specific biosynthetic glutamate dehydrogenase in Apodachlya. PMID:16657902

  18. Role of Nicotinamide Adenine Dinucleotide and Related Precursors as Therapeutic Targets for Age-Related Degenerative Diseases: Rationale, Biochemistry, Pharmacokinetics, and Outcomes.

    PubMed

    Braidy, Nady; Berg, Jade; Clement, James; Khorshidi, Fatemeh; Poljak, Anne; Jayasena, Tharusha; Grant, Ross; Sachdev, Perminder

    2018-05-11

    Nicotinamide adenine dinucleotide (NAD + ) is an essential pyridine nucleotide that serves as an essential cofactor and substrate for a number of critical cellular processes involved in oxidative phosphorylation and ATP production, DNA repair, epigenetically modulated gene expression, intracellular calcium signaling, and immunological functions. NAD + depletion may occur in response to either excessive DNA damage due to free radical or ultraviolet attack, resulting in significant poly(ADP-ribose) polymerase (PARP) activation and a high turnover and subsequent depletion of NAD + , and/or chronic immune activation and inflammatory cytokine production resulting in accelerated CD38 activity and decline in NAD + levels. Recent studies have shown that enhancing NAD + levels can profoundly reduce oxidative cell damage in catabolic tissue, including the brain. Therefore, promotion of intracellular NAD + anabolism represents a promising therapeutic strategy for age-associated degenerative diseases in general, and is essential to the effective realization of multiple benefits of healthy sirtuin activity. The kynurenine pathway represents the de novo NAD + synthesis pathway in mammalian cells. NAD + can also be produced by the NAD + salvage pathway. Recent Advances: In this review, we describe and discuss recent insights regarding the efficacy and benefits of the NAD + precursors, nicotinamide (NAM), nicotinic acid (NA), nicotinamide riboside (NR), and nicotinamide mononucleotide (NMN), in attenuating NAD + decline in degenerative disease states and physiological aging. Results obtained in recent years have shown that NAD + precursors can play important protective roles in several diseases. However, in some cases, these precursors may vary in their ability to enhance NAD + synthesis via their location in the NAD + anabolic pathway. Increased synthesis of NAD + promotes protective cell responses, further demonstrating that NAD + is a regulatory molecule associated with several biochemical pathways. In the next few years, the refinement of personalized therapy for the use of NAD + precursors and improved detection methodologies allowing the administration of specific NAD + precursors in the context of patients' NAD + levels will lead to a better understanding of the therapeutic role of NAD + precursors in human diseases. Antioxid. Redox Signal. 00, 000-000.

  19. Reducing intratumour acute hypoxia through bevacizumab treatment, referring to the response of quiescent tumour cells and metastatic potential

    PubMed Central

    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

  20. Feasibility of electrospray deposition for rapid screening of the cocrystal formation and single step, continuous production of pharmaceutical nanococrystals.

    PubMed

    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.

  1. Proinflammatory Actions of Visfatin/Nicotinamide Phosphoribosyltransferase (Nampt) Involve Regulation of Insulin Signaling Pathway and Nampt Enzymatic Activity*

    PubMed Central

    Jacques, Claire; Holzenberger, Martin; Mladenovic, Zvezdana; Salvat, Colette; Pecchi, Emilie; Berenbaum, Francis; Gosset, Marjolaine

    2012-01-01

    Visfatin (also termed pre-B-cell colony-enhancing factor (PBEF) or nicotinamide phosphoribosyltransferase (Nampt)) is a pleiotropic mediator acting on many inflammatory processes including osteoarthritis. Visfatin exhibits both an intracellular enzymatic activity (nicotinamide phosphoribosyltransferase, Nampt) leading to NAD synthesis and a cytokine function via the binding to its hypothetical receptor. We recently reported the role of visfatin in prostaglandin E2 (PGE2) synthesis in chondrocytes. Here, our aim was to characterize the signaling pathways involved in this response in exploring both the insulin receptor (IR) signaling pathway and Nampt activity. IR was expressed in human and murine chondrocytes, and visfatin triggered Akt phosphorylation in murine chondrocytes. Blocking IR expression with siRNA or activity using the hydroxy-2-naphthalenyl methyl phosphonic acid tris acetoxymethyl ester (HNMPA-(AM)3) inhibitor diminished visfatin-induced PGE2 release in chondrocytes. Moreover, visfatin-induced IGF-1R−/− chondrocytes released higher concentration of PGE2 than IGF-1R+/+ cells, a finding confirmed with an antibody that blocked IGF-1R. Using RT-PCR, we found that visfatin did not regulate IR expression and that an increased insulin release was also unlikely to be involved because insulin was unable to increase PGE2 release. Inhibition of Nampt activity using the APO866 inhibitor gradually decreased PGE2 release, whereas the addition of exogenous nicotinamide increased it. We conclude that the proinflammatory actions of visfatin in chondrocytes involve regulation of IR signaling pathways, possibly through the control of Nampt enzymatic activity. PMID:22399297

  2. Antidiabetic activity of aqueous root extract of Ichnocarpus frutescens in streptozotocin-nicotinamide induced type-II diabetes in rats

    PubMed Central

    Barik, Rakesh; Jain, Sanjay; Qwatra, Deep; Joshi, Amit; Tripathi, Girraj Sharan; Goyal, Ravi

    2008-01-01

    Objective: To evaluate the antidiabetic activity of aqueous extract of roots of Ichnocarpus frutescens in streptozotocin-nicotinamide induced type-II diabetes in rats. Materials and Methods: Streptozotocin-nicotinamide induced type-II diabetic rats (n = 6) were administered aqueous root extract (250 and 500 mg/kg, p.o.) of Ichnocarpus frutescens or vehicle (gum acacia solution) or standard drug glibenclamide (0.25 mg/kg) for 15 days. Blood samples were collected by retro-orbital puncture and were analyzed for serum glucose on days 0, 5, 10, and 15 by using glucose oxidase-peroxidase reactive strips and a glucometer. For oral glucose tolerance test, glucose (2 g/kg, p.o.) was administered to nondiabetic control rats and the rats treated with glibenclamide (10 mg/kg, p.o.) and aqueous root extract of Ichnocarpus frutescens. The serum glucose levels were analyzed at 0, 30, 60, and 120 min after drug administration. The effect of the extract on the body weight of the diabetic rats was also observed. Results: The aqueous root extract of Ichnocarpus frutescens (250 and 500 mg/kg, p.o.) induced significant reduction (P < 0.05) of fasting blood glucose levels in streptozotocin-nicotinamide induced type-II diabetic rats on the 10th and 15th days. In the oral glucose tolerance test, the extract increased the glucose tolerance. It also brought about an increase in the body weight of diabetic rats. Conclusion: It is concluded that Ichnocarpus frutescens has significant antidiabetic activity as it lowers the fasting blood sugar level in diabetic rats and increases the glucose tolerance. PMID:21264156

  3. Antidiabetic activity of aqueous root extract of Ichnocarpus frutescens in streptozotocin-nicotinamide induced type-II diabetes in rats.

    PubMed

    Barik, Rakesh; Jain, Sanjay; Qwatra, Deep; Joshi, Amit; Tripathi, Girraj Sharan; Goyal, Ravi

    2008-01-01

    To evaluate the antidiabetic activity of aqueous extract of roots of Ichnocarpus frutescens in streptozotocin-nicotinamide induced type-II diabetes in rats. Streptozotocin-nicotinamide induced type-II diabetic rats (n = 6) were administered aqueous root extract (250 and 500 mg/kg, p.o.) of Ichnocarpus frutescens or vehicle (gum acacia solution) or standard drug glibenclamide (0.25 mg/kg) for 15 days. Blood samples were collected by retro-orbital puncture and were analyzed for serum glucose on days 0, 5, 10, and 15 by using glucose oxidase-peroxidase reactive strips and a glucometer. For oral glucose tolerance test, glucose (2 g/kg, p.o.) was administered to nondiabetic control rats and the rats treated with glibenclamide (10 mg/kg, p.o.) and aqueous root extract of Ichnocarpus frutescens. The serum glucose levels were analyzed at 0, 30, 60, and 120 min after drug administration. The effect of the extract on the body weight of the diabetic rats was also observed. The aqueous root extract of Ichnocarpus frutescens (250 and 500 mg/kg, p.o.) induced significant reduction (P < 0.05) of fasting blood glucose levels in streptozotocin-nicotinamide induced type-II diabetic rats on the 10(th) and 15(th) days. In the oral glucose tolerance test, the extract increased the glucose tolerance. It also brought about an increase in the body weight of diabetic rats. It is concluded that Ichnocarpus frutescens has significant antidiabetic activity as it lowers the fasting blood sugar level in diabetic rats and increases the glucose tolerance.

  4. NAD+ repletion improves muscle function in muscular dystrophy and counters global PARylation.

    PubMed

    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.

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

    PubMed

    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.

  6. Integrated metabolomics and proteomics highlight altered nicotinamide and polyamine pathways in lung adenocarcinoma

    PubMed Central

    Fahrmann, Johannes F.; Grapov, Dmitry; Wanichthanarak, Kwanjeera; DeFelice, Brian C.; Salemi, Michelle R.; Rom, William N.; Gandara, David R.; Phinney, Brett S.; Fiehn, Oliver; Pass, Harvey

    2017-01-01

    Abstract Lung cancer is the leading cause of cancer mortality in the United States with non-small cell lung cancer adenocarcinoma being the most common histological type. Early perturbations in cellular metabolism are a hallmark of cancer, but the extent of these changes in early stage lung adenocarcinoma remains largely unknown. In the current study, an integrated metabolomics and proteomics approach was utilized to characterize the biochemical and molecular alterations between malignant and matched control tissue from 27 subjects diagnosed with early stage lung adenocarcinoma. Differential analysis identified 71 metabolites and 1102 proteins that delineated tumor from control tissue. Integrated results indicated four major metabolic changes in early stage adenocarcinoma (1): increased glycosylation and glutaminolysis (2); elevated Nrf2 activation (3); increase in nicotinic and nicotinamide salvaging pathways and (4) elevated polyamine biosynthesis linked to differential regulation of the s-adenosylmethionine/nicotinamide methyl-donor pathway. Genomic data from publicly available databases were included to strengthen proteomic findings. Our findings provide insight into the biochemical and molecular biological reprogramming that may accompany early stage lung tumorigenesis and highlight potential therapeutic targets. PMID:28049629

  7. Monocyte-derived extracellular Nampt-dependent biosynthesis of NAD+ protects the heart against pressure overload

    PubMed Central

    Yano, Masamichi; Akazawa, Hiroshi; Oka, Toru; Yabumoto, Chizuru; Kudo-Sakamoto, Yoko; Kamo, Takehiro; Shimizu, Yu; Yagi, Hiroki; Naito, Atsuhiko T.; Lee, Jong-Kook; Suzuki, Jun-ichi; Sakata, Yasushi; Komuro, Issei

    2015-01-01

    Nicotinamide phosphoribosyltransferase (Nampt) catalyzes the rate-limiting step in the salvage pathway for nicotinamide adenine dinucleotide (NAD+) biosynthesis, and thereby regulates the deacetylase activity of sirtuins. Here we show accommodative regulation of myocardial NAD+ by monocyte-derived extracellular Nampt (eNampt), which is essential for hemodynamic compensation to pressure overload. Although intracellular Nampt (iNampt) expression was decreased in pressure-overloaded hearts, myocardial NAD+ concentration and Sirt1 activity were preserved. In contrast, iNampt was up-regulated in spleen and monocytes, and circulating eNampt protein and nicotinamide mononucleotide (NMN), a key precursor of NAD+, were significantly increased. Pharmacological inhibition of Nampt by FK866 or depletion of monocytes/macrophages by clodronate liposomes disrupted the homeostatic mechanism of myocardial NAD+ levels and NAD+-dependent Sirt1 activity, leading to susceptibility to cardiomyocyte apoptosis and cardiac decompensation in pressure-overloaded mice. These biochemical and hemodynamic defects were prevented by systemic administration of NMN. Our studies uncover a crucial role of monocyte-derived eNampt in myocardial adaptation to pressure overload, and highlight a potential intervention controlling myocardial NAD+ against heart failure. PMID:26522369

  8. Combined adrenal failure and testicular adrenal rest tumor in a patient with nicotinamide nucleotide transhydrogenase deficiency.

    PubMed

    Hershkovitz, Eli; Arafat, Maram; Loewenthal, Neta; Haim, Alon; Parvari, Ruti

    2015-09-01

    The nicotinamide nucleotide transhydrogenase (NNT) enzyme is the main generator of nicotinamide adenine dinucleotide phosphate-oxidase in the mitochondrion. Mutations of the NNT gene have been recently implicated in familial glucocorticoid deficiency. We describe the long-term clinical course of a NNT-deficient 20-year-old patient with combined adrenal failure who had developed a testicular adrenal rest tumor and precocious puberty. The patient's medical records were reviewed. Whole-exome sequencing was performed on DNA obtained from the patient and family members. The patient experienced Addisonian crisis at 10 months of age. Enlarged testicular volume and precocious puberty, accompanied by increased testosterone levels, were noted at 6 years. Testicular biopsy revealed a adrenal rest tumor, which regressed after intensification of glucocorticoid treatment. Genetic studies disclosed a c.1163A>C, p.Tyr388Ser substitution on the NNT gene. This mutation is predicted to be damaging to NNT function. We demonstrated for the first time that the clinical spectrum of NNT deficiency may consist of mineralocorticoid deficiency and testicular involvement as well.

  9. NAMPT-Mediated NAD(+) Biosynthesis Is Essential for Vision In Mice.

    PubMed

    Lin, Jonathan B; Kubota, Shunsuke; Ban, Norimitsu; Yoshida, Mitsukuni; Santeford, Andrea; Sene, Abdoulaye; Nakamura, Rei; Zapata, Nicole; Kubota, Miyuki; Tsubota, Kazuo; Yoshino, Jun; Imai, Shin-Ichiro; Apte, Rajendra S

    2016-09-27

    Photoreceptor death is the endpoint of many blinding diseases. Identifying unifying pathogenic mechanisms in these diseases may offer global approaches for facilitating photoreceptor survival. We found that rod or cone photoreceptor-specific deletion of nicotinamide phosphoribosyltransferase (Nampt), the rate-limiting enzyme in the major NAD(+) biosynthetic pathway beginning with nicotinamide, caused retinal degeneration. In both cases, we could rescue vision with nicotinamide mononucleotide (NMN). Significantly, retinal NAD(+) deficiency was an early feature of multiple mouse models of retinal dysfunction, including light-induced degeneration, streptozotocin-induced diabetic retinopathy, and age-associated dysfunction. Mechanistically, NAD(+) deficiency caused metabolic dysfunction and consequent photoreceptor death. We further demonstrate that the NAD(+)-dependent mitochondrial deacylases SIRT3 and SIRT5 play important roles in retinal homeostasis and that NAD(+) deficiency causes SIRT3 dysfunction. These findings demonstrate that NAD(+) biosynthesis is essential for vision, provide a foundation for future work to further clarify the mechanisms involved, and identify a unifying therapeutic target for diverse blinding diseases. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  10. YCL047C/POF1 Is a Novel Nicotinamide Mononucleotide Adenylyltransferase (NMNAT) in Saccharomyces cerevisiae*

    PubMed Central

    Kato, Michiko; Lin, Su-Ju

    2014-01-01

    NAD+ is an essential metabolic cofactor involved in various cellular biochemical processes. Nicotinamide riboside (NR) is an endogenously produced key pyridine metabolite that plays important roles in the maintenance of NAD+ pool. Using a NR-specific cell-based screen, we identified mutants that exhibit altered NR release phenotype. Yeast cells lacking the ORF YCL047C/POF1 release considerably more NR compared with wild type, suggesting that POF1 plays an important role in NR/NAD+ metabolism. The amino acid sequence of Pof1 indicates that it is a putative nicotinamide mononucleotide adenylyltransferase (NMNAT). Unlike other yeast NMNATs, Pof1 exhibits NMN-specific adenylyltransferase activity. Deletion of POF1 significantly lowers NAD+ levels and decreases the efficiency of NR utilization, resistance to oxidative stress, and NR-induced life span extension. We also show that NR is constantly produced by multiple nucleotidases and that the intracellular NR pools are likely to be compartmentalized, which contributes to the regulation of NAD+ homeostasis. Our findings may contribute to the understanding of the molecular basis and regulation of NAD+ metabolism in higher eukaryotes. PMID:24759102

  11. The NAD+ Precursor Nicotinamide Riboside Rescues Mitochondrial Defects and Neuronal Loss in iPSC and Fly Models of Parkinson's Disease.

    PubMed

    Schöndorf, David C; Ivanyuk, Dina; Baden, Pascale; Sanchez-Martinez, Alvaro; De Cicco, Silvia; Yu, Cong; Giunta, Ivana; Schwarz, Lukas K; Di Napoli, Gabriele; Panagiotakopoulou, Vasiliki; Nestel, Sigrun; Keatinge, Marcus; Pruszak, Jan; Bandmann, Oliver; Heimrich, Bernd; Gasser, Thomas; Whitworth, Alexander J; Deleidi, Michela

    2018-06-05

    While mitochondrial dysfunction is emerging as key in Parkinson's disease (PD), a central question remains whether mitochondria are actual disease drivers and whether boosting mitochondrial biogenesis and function ameliorates pathology. We address these questions using patient-derived induced pluripotent stem cells and Drosophila models of GBA-related PD (GBA-PD), the most common PD genetic risk. Patient neurons display stress responses, mitochondrial demise, and changes in NAD+ metabolism. NAD+ precursors have been proposed to ameliorate age-related metabolic decline and disease. We report that increasing NAD+ via the NAD+ precursor nicotinamide riboside (NR) significantly ameliorates mitochondrial function in patient neurons. Human neurons require nicotinamide phosphoribosyltransferase (NAMPT) to maintain the NAD+ pool and utilize NRK1 to synthesize NAD+ from NAD+ precursors. Remarkably, NR prevents the age-related dopaminergic neuronal loss and motor decline in fly models of GBA-PD. Our findings suggest NR as a viable clinical avenue for neuroprotection in PD and other neurodegenerative diseases. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  12. Assimilation of NAD(+) precursors in Candida glabrata.

    PubMed

    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.

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

    PubMed

    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.

  14. Novel Directions for Diabetes Mellitus Drug Discovery

    PubMed Central

    Maiese, Kenneth; Chong, Zhao Zhong; Shang, Yan Chen; Wang, Shaohui

    2012-01-01

    Introduction Diabetes mellitus impacts almost 200 million individuals worldwide and leads to debilitating complications. New avenues of drug discovery must target the underlying cellular processes of oxidative stress, apoptosis, autophagy, and inflammation that can mediate multi-system pathology during diabetes mellitus. Areas Covered We examine novel directions for drug discovery that involve the β-nicotinamide adenine dinucleotide (NAD+) precursor nicotinamide, the cytokine erythropoietin, the NAD+-dependent protein histone deacetylase SIRT1, the serine/threonine-protein kinase mammalian target of rapamycin (mTOR), and the wingless pathway. Implications for the targeting of these pathways that oversee gluconeogenic genes, insulin signaling and resistance, fatty acid beta-oxidation, inflammation, and cellular survival are presented. Expert Opinion Nicotinamide, erythropoietin, and the downstram pathways of SIRT1, mTOR, forkhead transcription factors, and wingless signaling offer exciting prospects for novel directions of drug discovery for the treatment of metabolic disorders. Future investigations must dissect the complex relationship and fine modulation of these pathways for the successful translation of robust reparative and regenerative strategies against diabetes mellitus and the complications of this disorder. PMID:23092114

  15. Overexpression of NRK1 ameliorates diet- and age-induced hepatic steatosis and insulin resistance.

    PubMed

    Fan, Rui; Cui, Jing; Ren, Feng; Wang, Qingzhi; Huang, Yanmei; Zhao, Bin; Wei, Lai; Qian, Xinlai; Xiong, Xiwen

    2018-06-02

    NAD + is a co-enzyme in redox reactions and a substrate required for activity of various enzyme families, including sirtuins and poly(ADP-ribose) polymerases. Dietary supplementation of NAD + precursors nicotinamide mononucleotide (NMN) or nicotinamide riboside (NR) protects against metabolic disease, neurodegenerative disorders and age-related physiological decline in mammals. Here we sought to identify the roles of nicotinamide riboside kinase 1 (NRK1) plays in regulating hepatic NAD + biosynthesis and lipid metabolism. Using adenovirus mediated gene transduction to overexpress or knockdown NRK1 in mouse liver, we have demonstrated that NRK1 is critical for maintaining hepatic NAD + levels and triglyceride content. We have further shown that the hepatic expression of Nmrk1 mRNA is significantly decreased either in mice treated with high-fat diet or in aged mice. However, adenoviral delivery of NRK1 in these diet- and age-induced mice elevates hepatic NAD + levels, reduces hepatic steatosis, and improves glucose tolerance and insulin sensitivity. Our results provide important insights in targeting NRK1 for treating hepatic steatosis. Copyright © 2018 Elsevier Inc. All rights reserved.

  16. A Key Enzyme of the NAD+ Salvage Pathway in Thermus thermophilus: Characterization of Nicotinamidase and the Impact of Its Gene Deletion at High Temperatures

    PubMed Central

    Taniguchi, Hironori; Sungwallek, Sathidaphorn; Chotchuang, Phatcharin; Okano, Kenji

    2017-01-01

    ABSTRACT 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 (Km of 17 μM, kcat of 50 s−1, kcat/Km of 3.0 × 103 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. PMID:28630126

  17. Nicotinamide phosphoribosyltransferase protects against ischemic stroke through SIRT1-dependent adenosine monophosphate-activated kinase pathway.

    PubMed

    Wang, Pei; Xu, Tian-Ying; Guan, Yun-Feng; Tian, Wei-Wei; Viollet, Benoit; Rui, Yao-Cheng; Zhai, Qi-Wei; Su, Ding-Feng; Miao, Chao-Yu

    2011-02-01

    Stroke is a leading cause of mortality and disability. Nicotinamide phosphoribosyltransferase (Nampt) is the rate-limiting enzyme in mammalian nicotinamide adenine dinucleotide (NAD)(+) biosynthesis and contributes to cell fate decisions. However, the role of Nampt in brain and stroke remains to be investigated. We used lentivirus-mediated Nampt overexpression and knockdown to manipulate Nampt expression and explore the effects of Nampt in neuronal survival on ischemic stress both in vivo and in vitro. We also used adenosine monophosphate (AMP)-activated kinase-α2 (AMPKα2) and silent mating type information regulation 2 homolog 1 (SIRT1) knockout mice to investigate the underlying mechanisms of Nampt neuroprotection. Nampt inhibition by a highly-specific Nampt inhibitor, FK866, aggravated brain infarction in experimentally cerebral ischemia rats, whereas Nampt overexpression in local brain and Nampt enzymatic product nicotinamide mononucleotide (NMN) reduced ischemia-induced cerebral injuries. Nampt overexpression and knockdown regulated neuron survival via the AMPK pathway. Neuroprotection of Nampt was abolished in AMPKα2(-/-) neurons. In neurons, Nampt positively modulated NAD(+) levels and thereby controlled SIRT1 activity. SIRT1 coprecipitated with serine/threonine kinase 11 (LKB1), an upstream kinase of AMPK, and promoted LKB1 deacetylation in neurons. Nampt-induced LKB1 deacetylation and AMPK activation disappeared in SIRT1(-/-) neurons. In contrast, Ca(2+) /calmodulin-dependent protein kinase kinase-β (CaMKK-β), another upstream kinase of AMPK, was not involved in the neuroprotection of Nampt. More important, Nampt overexpression-induced neuroprotection was abolished in SIRT1(+/-) and AMPKα2(-/-) mice. Our findings reveal that Nampt protects against ischemic stroke through rescuing neurons from death via the SIRT1-dependent AMPK pathway and indicate that Nampt is a new therapeutic target for stroke. Copyright © 2011 American Neurological Association.

  18. Effects of employing a 10B-carrier and manipulating intratumour hypoxia on local tumour response and lung metastatic potential in boron neutron capture therapy

    PubMed Central

    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

  19. Profiling Redox and Energy Coenzymes in Whole Blood, Tissue and Cells Using NMR Spectroscopy.

    PubMed

    Gowda, G A Nagana

    2018-05-14

    Coenzymes of cellular redox reactions and cellular energy, as well as antioxidants mediate biochemical reactions fundamental to the functioning of all living cells. Conventional analysis methods lack the opportunity to evaluate these important redox and energy coenzymes and antioxidants in a single step. Major coenzymes include redox coenzymes: NAD⁺ (oxidized nicotinamide adenine dinucleotide), NADH (reduced nicotinamide adenine dinucleotide), NADP⁺ (oxidized nicotinamide adenine dinucleotide phosphate) and NADPH (reduced nicotinamide adenine dinucleotide phosphate); energy coenzymes: ATP (adenosine triphosphate), ADP (adenosine diphosphate) and AMP (adenosine monophosphate); and antioxidants: GSSG (oxidized glutathione) and GSH (reduced glutathione). We show here that a simple ¹H NMR experiment can measure these coenzymes and antioxidants in tissue and whole blood apart from a vast pool of other metabolites. In addition, focused on the goal of identification of coenzymes in subcellular fractions, we demonstrate analysis of coenzymes in the cytoplasm using breast cancer cells. Owing to their unstable nature, or low concentrations, most of the coenzymes either evade detection or lose their integrity when established sample preparation and analysis methods are used. To overcome this challenge, here we describe the development of new methods to detect these molecules without affecting the integrity of other metabolites. We used an array of 1D and 2D NMR methods, chemical shift databases, pH measurements and spiking with authentic compounds to establish the identity of peaks for the coenzymes and antioxidants in NMR spectra. Interestingly, while none of the coenzymes and antioxidants were detected in plasma, they were abundant in whole blood. Considering that the coenzymes and antioxidants represent a sensitive measure of human health and risk for numerous diseases, the presented NMR methods to measure them in one step potentially open new opportunities in the metabolomics field.

  20. d-3-Hydroxybutyrate dehydrogenase from Rhodopseudomonas spheroides. Kinetic mechanism from steady-state kinetics of the reaction catalysed by the enzyme in solution and covalently attached to diethylaminoethylcellulose

    PubMed Central

    Preuveneers, M. J.; Peacock, D.; Crook, E. M.; Clark, J. B.; Brocklehurst, K.

    1973-01-01

    1. The reversible NAD+-linked oxidation of d-3-hydroxybutyrate to acetoacetate in 0.1m-sodium pyrophosphate buffer, pH8.5, at 25.0°C, catalysed by d-3-hydroxybutyrate dehydrogenase (d-3-hydroxybutyrate–NAD+ oxidoreductase, EC 1.1.1.30), was studied by initial-velocity, dead-end inhibition and product-inhibition analysis. 2. The reactions were carried out on (a) the soluble enzyme from Rhodopseudomonas spheroides and (b) an insoluble derivative of this enzyme prepared by its covalent attachment to DEAE-cellulose by using 2-amino-4,6-dichloro-s-triazine as coupling agent. 3. The insolubilized enzyme preparation contained 5mg of protein/g wet wt. of total material, and when freshly prepared its specific activity was 1.2μmol/min per mg of protein, which is 67% of that of the soluble dialysed enzyme. 4. The reactions catalysed by both the enzyme in solution and the insolubilized enzyme were shown to follow sequential pathways in which the nicotinamide nucleotides bind obligatorily first to the enzyme. Evidence is presented for kinetically significant ternary complexes and that the rate-limiting step(s) of both catalyses probably involves isomerization of the enzyme–nicotinamide nucleotide complexes and/or dissociation of the nicotinamide nucleotides from the enzyme. Both catalyses therefore are probably best described as ordered Bi Bi mechanisms, possibly with multiple enzyme–nicotinamide nucleotide complexes. 5. The kinetic parameters and the calculable rate constants for the catalysis by the soluble enzyme are similar to the corresponding parameters and rate constants for the catalysis by the insolubilized enzyme. PMID:4352835

  1. A Key Enzyme of the NAD+ Salvage Pathway in Thermus thermophilus: Characterization of Nicotinamidase and the Impact of Its Gene Deletion at High Temperatures.

    PubMed

    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.

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

    PubMed

    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.

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

    PubMed

    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.

  4. 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.

    PubMed

    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.

  5. 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

    PubMed Central

    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

    Objectives 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. Background 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. Methods 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. Results 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). Conclusions 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. PMID:29211728

  6. Identification of a nicotinamide/nicotinate mononucleotide adenylyltransferase in Giardia lamblia (GlNMNAT).

    PubMed

    Forero-Baena, Nicolás; Sánchez-Lancheros, Diana; Buitrago, July Constanza; Bustos, Victor; Ramírez-Hernández, María Helena

    2015-01-01

    Giardia lamblia is an intestinal protozoan parasite that causes giardiasis, a disease of high prevalence in Latin America, Asia and Africa. Giardiasis leads to poor absorption of nutrients, severe electrolyte loss and growth retardation. In addition to its clinical importance, this parasite is of special biological interest due to its basal evolutionary position and simplified metabolism, which has not been studied thoroughly. One of the most important and conserved metabolic pathways is the biosynthesis of nicotinamide adenine dinucleotide (NAD). This molecule is widely known as a coenzyme in multiple redox reactions and as a substrate in cellular processes such as synthesis of Ca 2+ mobilizing agents, DNA repair and gene expression regulation. There are two pathways for NAD biosynthesis, which converge at the step catalyzed by nicotinamide/nicotinate mononucleotide adenylyltransferase (NMNAT, EC 2.7.7.1/18). Using bioinformatics tools, we found two NMNAT sequences in Giardia lamblia ( glnmnat-a and glnmnat-b ). We first verified the identity of the sequences in silico . Subsequently, glnmnat-a was cloned into an expression vector. The recombinant protein (His-GlNMNAT) was purified by nickel-affinity binding and was used in direct in vitro enzyme assays assessed by C18-HPLC, verifying adenylyltransferase activity with both nicotinamide (NMN) and nicotinic acid (NAMN) mononucleotides. Optimal reaction pH and temperature were 7.3 and 26 °C. Michaelis-Menten kinetics were observed for NMN and ATP, but saturation was not accomplished with NAMN, implying low affinity yet detectable activity with this substrate. Double-reciprocal plots showed no cooperativity for this enzyme. This represents an advance in the study of NAD metabolism in Giardia spp.

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

    PubMed Central

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

    2015-01-01

    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. PMID:26385918

  8. 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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Janssens, Geert O., E-mail: g.janssens@rther.umcn.nl; Terhaard, Chris H.; Doornaert, Patricia A.

    2012-02-01

    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 (moistmore » 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.« less

  9. Oxidation of ethane by an Acremonium species.

    PubMed Central

    Davies, J S; Wellman, A M; Zajic, J E

    1976-01-01

    Ethane oxidation was studied in ethane-grown resting cells (mycelia) of an Acremonium sp. and in cell-free preparations of such mycelia. From resting cell experiments evidence was found for a pathway of ethane oxidation via ethanol, acetaldehyde, and acetic acid. In vitro studies indicated that ethane-oxidizing activity in such mycelia occurred predominantly in the microsomal fraction of crude homogenates. Microsomal preparations were inactive in the absence of added coenzyme. Marked stimulation of activity was obtained in such preparations with reduced nicotinamide adenine dinucleotide phosphate and to a much lesser degree with nicotinamide adenine dinucleotide phosphate. Ethane oxidation was inhibited by sodium azide and carbon monoxide. PMID:9900

  10. Physiological Study on Association between Nicotinamide N-Methyltransferase Gene Polymorphisms and Hyperlipidemia

    PubMed Central

    Zhu, Xiao-Juan; Lin, Ya-Jun; Chen, Wei; Wang, Ya-Hui; Qiu, Li-Qiang; Cai, Can-Xin; Xiong, Qun; Chen, Fei; Chen, Li-Hui; Zhou, Qiong

    2016-01-01

    Nicotinamide N-methyltransferase (NNMT) catalyzes the methylation of nicotinamide. Our previous works indicate that NNMT is involved in the body mass index and energy metabolism, and recently the association between a SNP (rs694539) of NNMT and a variety of cardiovascular diseases was reported. At present, more than 200 NNMT single nucleotide polymorphisms (SNPs) have been identified in the databases of the human genome projects; however, the association between rs694539 variation and hyperlipidemia has not been reported yet, and whether there are any SNPs in NNMT significantly associated with hyperlipidemia is still unclear. In this paper, we selected 19 SNPs in NNMT as the tagSNPs using Haploview software (Haploview 4.2) first and then performed a case-control study to observe the association between these tagSNPs and hyperlipidemia and finally applied physiological approaches to explore the possible mechanisms through which the NNMT polymorphism induces hyperlipidemia. The results show that a SNP (rs1941404) in NNMT is significantly associated with hyperlipidemia, and the influence of rs1941404 variation on the resting energy expenditure may be the possible mechanism for rs1941404 variation to induce hyperlipidemia. PMID:27999813

  11. More than skin deep? Potential nicotinamide treatment applications in chronic kidney transplant recipients

    PubMed Central

    Bostom, Andrew G; Merhi, Basma; Walker, Joanna; Robinson-Bostom, Leslie

    2016-01-01

    Non-melanoma cutaneous carcinomas, or skin cancers, predominantly squamous cell carcinomas (SCCs), are the most common malignancies occurring in kidney transplant recipients (KTRs). Squamous cell carcinoma risk is dramatically elevated in KTRs, occurring at rates of up 45-250 times those reported in general populations. New non-melanoma skin cancers in KTRs with a prior non-melanoma skin cancer also develop at 3-times the rate reported in non-KTRs with the same clinical history. The unique aggressiveness of SCCs in KTRs increases patient morbidity, due to the high rate of new lesions requiring treatment, frequently surgical excision. Oral nicotinamide shows promise in the chemoprevention of the especially aggressive non-melanoma skin cancers which occur in KTRs. This benefit might be conferred via its inhibition of sirtuin enzymatic pathways. Nicotinamide’s concurrent hypophosphatemic effect may also partially ameliorate the disturbed calcium-phosphorus homeostasis in these patients-a putative risk factor for mortality, and graft failure. Conceivably, a phase 3 trial of nicotinamide for the prevention of non-melanoma skin cancers in KTRs, lasting at least 12-mo, could also incorporate imaging and laboratory measures which assess nicotinamide’s impact on subclinical cardiovascular and chronic kidney disease risk, and progression. PMID:28058215

  12. NNMT activation can contribute to the development of fatty liver disease by modulating the NAD + metabolism.

    PubMed

    Komatsu, Motoaki; Kanda, Takeshi; Urai, Hidenori; Kurokochi, Arata; Kitahama, Rina; Shigaki, Shuhei; Ono, Takashi; Yukioka, Hideo; Hasegawa, Kazuhiro; Tokuyama, Hirobumi; Kawabe, Hiroshi; Wakino, Shu; Itoh, Hiroshi

    2018-06-05

    Nicotinamide N-methyltransferase (NNMT) catalyses the reaction between nicotinamide (NAM) and S-adenosylmethionine to produce 1-methylnicotinamide and S-adenosylhomocysteine. Recently, this enzyme has also been reported to modulate hepatic nutrient metabolism, but its role in the liver has not been fully elucidated. We developed transgenic mice overexpressing NNMT to elucidate its role in hepatic nutrient metabolism. When fed a high fat diet containing NAM, a precursor for nicotinamide adenine dinucleotide (NAD) + , these NNMT-overexpressing mice exhibit fatty liver deterioration following increased expression of the genes mediating fatty acid uptake and decreased very low-density lipoprotein secretion. NNMT overactivation decreased the NAD + content in the liver and also decreased gene activity related to fatty acid oxidation by inhibiting NAD + -dependent deacetylase Sirt3 function. Moreover, the transgenic mice showed liver fibrosis, with the induction of inflammatory and fibrosis genes. Induced NNMT expression decreased the tissue methylation capacity, thereby reducing methylation of the connective tissue growth factor (CTGF) gene promoter, resulting in increased CTGF expression. These data indicate that NNMT links the NAD + and methionine metabolic pathways and promotes liver steatosis and fibrosis. Therefore, targeting NNMT may serve as a therapeutic strategy for treating fatty liver and fibrosis.

  13. Evaluation of Colorimetric Methods Using Nicotinamide for Rapid Detection of Pyrazinamide Resistance in Mycobacterium tuberculosis▿

    PubMed Central

    Mirabal, Niuris C.; Yzquierdo, Sergio L.; Lemus, Dihadenys; Madruga, Mariela; Milián, Yoslaine; Echemendía, Miguel; Takiff, Howard; Martin, Anandi; Van der Stuyf, Patrick; Palomino, Juan Carlos; Montoro, Ernesto

    2010-01-01

    The direct detection of pyrazinamide resistance in Mycobacterium tuberculosis is sufficiently difficult that many laboratories do not attempt it. Most pyrazinamide resistance is caused by mutations that inactivate the pyrazinamidase enzyme needed to convert the prodrug pyrazinamide to its active form. We evaluated two newer and simpler methods to assess pyrazinamidase activity, the nitrate reductase and malachite green microtube assays, using nicotinamide in place of pyrazinamide. A total of 102 strains were tested by these methods and the results compared with those obtained by the classic Wayne assay. Mutations in the pncA gene were identified by sequencing the pncA genes from all isolates in which pyrazinamide resistance was detected by any of the three methods. Both the nitrate reductase and malachite green microtube assays showed sensitivities of 93.75% and specificities of 97.67%. Mutations in the pncA gene were found in 14 of 16 strains that were pyrazinamide resistant and in 1 of 4 strains that were sensitive by the Wayne assay. Both of these simple methods, used with nicotinamide, are promising and inexpensive alternatives for the rapid detection of pyrazinamide resistance in limited-resource countries. PMID:20554826

  14. Coupling of NAD+ Biosynthesis and Nicotinamide Ribosyl Transport: Characterization of NadR Ribonucleotide Kinase Mutants of Haemophilus influenzae

    PubMed Central

    Merdanovic, Melisa; Sauer, Elizabeta; Reidl, Joachim

    2005-01-01

    Previously, we characterized a pathway necessary for the processing of NAD+ and for uptake of nicotinamide riboside (NR) in Haemophilus influenzae. Here we report on the role of NadR, which is essential for NAD+ utilization in this organism. Different NadR variants with a deleted ribonucleotide kinase domain or with a single amino acid change were characterized in vitro and in vivo with respect to cell viability, ribonucleotide kinase activity, and NR transport. The ribonucleotide kinase mutants were viable only in a nadV+ (nicotinamide phosphoribosyltransferase) background, indicating that the ribonucleotide kinase domain is essential for cell viability in H. influenzae. Mutations located in the Walker A and B motifs and the LID region resulted in deficiencies in both NR phosphorylation and NR uptake. The ribonucleotide kinase function of NadR was found to be feedback controlled by NAD+ under in vitro conditions and by NAD+ utilization in vivo. Taken together, our data demonstrate that the NR phosphorylation step is essential for both NR uptake across the inner membrane and NAD+ synthesis and is also involved in controlling the NAD+ biosynthesis rate. PMID:15968050

  15. Synthesis and crystal structure of the [Co{sub 2}(Nicotinamide){sub 4}(C{sub 4}H{sub 9}COO){sub 4}(H{sub 2}O)] complex

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sadikov, G. G., E-mail: sadgg@igic.ras.ru; Antsyshkina, A. S.; Koksharova, T. V.

    2007-09-15

    The [Co{sub 2}L{sub 4}(C{sub 4}H{sub 9}COO){sub 4}(H{sub 2}O)] coordination compound of cobalt(II) valerate with nicotinamide (L) is synthesized and studied by IR spectroscopy. The crystal structure of the synthesized compound is determined. The crystals are triclinic, and the unit cell parameters are as follows: a = 10.2759(10) A, b = 16.3858(10) A, c = 16.4262(10) A, {alpha} = 100.538(10) deg., {beta} = 101.199(10) deg., {gamma} = 90.813 (10) deg., Z = 2, and space group P1-bar. The structural units of the crystal are dimeric molecular complexes in which pairs of cobalt atoms are linked by triple bridges formed by oxygenmore » atoms of two bidentately coordinated valerate anions and a water molecule. The octahedral coordination of each cobalt atom is complemented by the pyridine nitrogen atoms of two nicotinamide ligands and the oxygen atom of the monodentate valerate group. The hydrocarbon chains of the valerate anions are disordered over two or three positions each.« less

  16. YCL047C/POF1 is a novel nicotinamide mononucleotide adenylyltransferase (NMNAT) in Saccharomyces cerevisiae.

    PubMed

    Kato, Michiko; Lin, Su-Ju

    2014-05-30

    NAD(+) is an essential metabolic cofactor involved in various cellular biochemical processes. Nicotinamide riboside (NR) is an endogenously produced key pyridine metabolite that plays important roles in the maintenance of NAD(+) pool. Using a NR-specific cell-based screen, we identified mutants that exhibit altered NR release phenotype. Yeast cells lacking the ORF YCL047C/POF1 release considerably more NR compared with wild type, suggesting that POF1 plays an important role in NR/NAD(+) metabolism. The amino acid sequence of Pof1 indicates that it is a putative nicotinamide mononucleotide adenylyltransferase (NMNAT). Unlike other yeast NMNATs, Pof1 exhibits NMN-specific adenylyltransferase activity. Deletion of POF1 significantly lowers NAD(+) levels and decreases the efficiency of NR utilization, resistance to oxidative stress, and NR-induced life span extension. We also show that NR is constantly produced by multiple nucleotidases and that the intracellular NR pools are likely to be compartmentalized, which contributes to the regulation of NAD(+) homeostasis. Our findings may contribute to the understanding of the molecular basis and regulation of NAD(+) metabolism in higher eukaryotes. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Coupling of NAD+ biosynthesis and nicotinamide ribosyl transport: characterization of NadR ribonucleotide kinase mutants of Haemophilus influenzae.

    PubMed

    Merdanovic, Melisa; Sauer, Elizabeta; Reidl, Joachim

    2005-07-01

    Previously, we characterized a pathway necessary for the processing of NAD+ and for uptake of nicotinamide riboside (NR) in Haemophilus influenzae. Here we report on the role of NadR, which is essential for NAD+ utilization in this organism. Different NadR variants with a deleted ribonucleotide kinase domain or with a single amino acid change were characterized in vitro and in vivo with respect to cell viability, ribonucleotide kinase activity, and NR transport. The ribonucleotide kinase mutants were viable only in a nadV+ (nicotinamide phosphoribosyltransferase) background, indicating that the ribonucleotide kinase domain is essential for cell viability in H. influenzae. Mutations located in the Walker A and B motifs and the LID region resulted in deficiencies in both NR phosphorylation and NR uptake. The ribonucleotide kinase function of NadR was found to be feedback controlled by NAD+ under in vitro conditions and by NAD+ utilization in vivo. Taken together, our data demonstrate that the NR phosphorylation step is essential for both NR uptake across the inner membrane and NAD+ synthesis and is also involved in controlling the NAD+ biosynthesis rate.

  18. Structure-Based Optimization of Arylamides as Inhibitors of Soluble Epoxide Hydrolase

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Eldrup, Anne B.; Soleymanzadeh, Fariba; Taylor, Steven J.

    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 livermore » 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.« less

  19. A Rice Bran Oil Diet Improves Lipid Abnormalities and Suppress Hyperinsulinemic Responses in Rats with Streptozotocin/Nicotinamide-Induced Type 2 Diabetes

    PubMed Central

    Chou, Tsui-Wei; Ma, Chien-Ya; Cheng, Hsing-Hsien; Chen, Ya-Yen; Lai, Ming-Hoang

    2009-01-01

    The aim of this study was to determine the effects of rice bran oil (RBO) on lipid metabolism and insulin resistance in rats with streptozotocin/nicotinamide-induced type 2 diabetes mellitus (T2DM). Rats were divided into two groups: the control group (15% soybean oil, contains 0 g γ-oryzanol and 0 g γ-tocotrienol/150 g oil for 5 weeks) and the RBO group (15% RBO, contains 5.25 g γ-oryzanol and 0.9 g γ-tocotrienol/150 g oil for 5 weeks). Compared with the control group, the RBO group had a lower plasma nonesterified fatty acid concentration, ratio of total to high-density-lipoprotein cholesterol, hepatic cholesterol concentration, and area under the curve for insulin. The RBO group had a higher high-density-lipoprotein cholesterol concentration and greater excretion of fecal neutral sterols and bile acid than did the control group. RBO may improve lipid abnormalities, reduce the atherogenic index, and suppress the hyperinsulinemic response in rats with streptozotocin/nicotinamide-induced T2DM. In addition, RBO can lead to increased fecal neutral sterol and bile acid excretion. PMID:19590704

  20. Nicotinamide mononucleotide (NMN) supplementation ameliorates the impact of maternal obesity in mice: comparison with exercise.

    PubMed

    Uddin, Golam Mezbah; Youngson, Neil A; Doyle, Bronte M; Sinclair, David A; Morris, Margaret J

    2017-11-08

    Maternal overnutrition increases the risk of long-term metabolic dysfunction in offspring. Exercise improves metabolism partly by upregulating mitochondrial biogenesis or function, via increased levels of nicotinamide adenine dinucleotide (NAD + ). We have shown that the NAD + precursor, nicotinamide mononucleotide (NMN) can reverse some of the negative consequences of high fat diet (HFD) consumption. To investigate whether NMN can impact developmentally-set metabolic deficits, we compared treadmill exercise and NMN injection in offspring of obese mothers. Five week old lean and obese female C57BL6/J mice were mated with chow fed males. Female offspring weaned onto HFD were given treadmill exercise for 9 weeks, or NMN injection daily for 18 days. Maternal obesity programmed increased adiposity and liver triglycerides, with decreased glucose tolerance, liver NAD + levels and citrate synthase activity in offspring. Both interventions reduced adiposity, and showed a modest improvement in glucose tolerance and improved markers of mitochondrial function. NMN appeared to have stronger effects on liver fat catabolism (Hadh) and synthesis (Fasn) than exercise. The interventions appeared to exert the most global benefit in mice that were most metabolically challenged (HFD-consuming offspring of obese mothers). This work encourages further study to confirm the suitability of NMN for use in reversing metabolic dysfunction linked to programming by maternal obesity.

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

    PubMed

    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.

  2. Pyridine metabolism in tea plants: salvage, conjugate formation and catabolism.

    PubMed

    Ashihara, Hiroshi; Deng, Wei-Wei

    2012-11-01

    Pyridine compounds, including nicotinic acid and nicotinamide, are key metabolites of both the salvage pathway for NAD and the biosynthesis of related secondary compounds. We examined the in situ metabolic fate of [carbonyl-(14)C]nicotinamide, [2-(14)C]nicotinic acid and [carboxyl-(14)C]nicotinic acid riboside in tissue segments of tea (Camellia sinensis) plants, and determined the activity of enzymes involved in pyridine metabolism in protein extracts from young tea leaves. Exogenously supplied (14)C-labelled nicotinamide was readily converted to nicotinic acid, and some nicotinic acid was salvaged to nicotinic acid mononucleotide and then utilized for the synthesis of NAD and NADP. The nicotinic acid riboside salvage pathway discovered recently in mungbean cotyledons is also operative in tea leaves. Nicotinic acid was converted to nicotinic acid N-glucoside, but not to trigonelline (N-methylnicotinic acid), in any part of tea seedlings. Active catabolism of nicotinic acid was observed in tea leaves. The fate of [2-(14)C]nicotinic acid indicates that glutaric acid is a major catabolite of nicotinic acid; it was further metabolised, and carbon atoms were finally released as CO(2). The catabolic pathway observed in tea leaves appears to start with the nicotinic acid N-glucoside formation; this pathway differs from catabolic pathways observed in microorganisms. Profiles of pyridine metabolism in tea plants are discussed.

  3. Ligand Binding Phenomena that Pertain to the Metabolic Function of Renalase

    PubMed Central

    Beaupre, Brett A.; Roman, Joseph V.; Hoag, Matthew R.; Meneely, Kathleen M.; Silvaggi, Nicholas R.; Lamb, Audrey L.; Moran, Graham R.

    2017-01-01

    Renalase catalyzes the oxidation of isomers of β-NAD(P)H that carry the hydride in the 2 or 6 positions of the nicotinamide base to form β-NAD(P)+. This activity is thought to alleviate inhibition of multiple β-NAD(P)-dependent enzymes of primary and secondary metabolism by these isomers. Here we present evidence for a variety of ligand binding phenomena relevant to the function of renalase. We offer evidence of the potential for primary metabolism inhibition with structures of malate dehydrogenase and lactate dehydrogenase bound to the 6-dihydroNAD isomer. The previously observed preference of renalase from Pseudomonas for NAD-derived substrates over those derived from NADP is accounted for by the structure of the enzyme in complex with NADPH. We also show that nicotinamide nucleosides and mononucloetides reduced in the 2- and 6-positions are renalase substrates, but bind weakly. A seven-fold enhancement of acquisition (kred/Kd) for 6-dihydronicotinamide riboside was observed for human renalase in the presence of ADP. However, generally the addition of complement ligands, ADP for mononucloetide or AMP for nucleoside substrates, did not enhance the reductive half-reaction. Non-substrate nicotinamide nucleosides or nucleotides bind weakly suggesting that only β-NADH and β-NADPH compete with dinucleotide substrates for access to the active site. PMID:27769837

  4. Discovery of potent and selective sirtuin 2 (SIRT2) inhibitors using a fragment-based approach.

    PubMed

    Cui, Huaqing; Kamal, Zeeshan; Ai, Teng; Xu, Yanli; More, Swati S; Wilson, Daniel J; Chen, Liqiang

    2014-10-23

    Sirtuin 2 (SIRT2) is one of the sirtuins, a family of NAD(+)-dependent deacetylases that act on a variety of histone and non-histone substrates. Accumulating biological functions and potential therapeutic applications have drawn interest in the discovery and development of SIRT2 inhibitors. Herein we report our discovery of novel SIRT2 inhibitors using a fragment-based approach. Inspired by the purported close binding proximity of suramin and nicotinamide, we prepared two sets of fragments, namely, the naphthylamide sulfonic acids and the naphthalene-benzamides and -nicotinamides. Biochemical evaluation of these two series provided structure-activity relationship (SAR) information, which led to the design of (5-benzamidonaphthalen-1/2-yloxy)nicotinamide derivatives. Among these inhibitors, one compound exhibited high anti-SIRT2 activity (48 nM) and excellent selectivity for SIRT2 over SIRT1 and SIRT3. In vitro, it also increased the acetylation level of α-tubulin, a well-established SIRT2 substrate, in both concentration- and time-dependent manners. Further kinetic studies revealed that this compound behaves as a competitive inhibitor against the peptide substrate and most likely as a noncompetitive inhibitor against NAD(+). Taken together, these results indicate that we have discovered a potent and selective SIRT2 inhibitor whose novel structure merits further exploration.

  5. Effect of bevacizumab combined with boron neutron capture therapy on local tumor response and lung metastasis

    PubMed Central

    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

  6. Auxotrophic Actinobacillus pleurpneumoniae grows in multispecies biofilms without the need for nicotinamide-adenine dinucleotide (NAD) supplementation.

    PubMed

    Loera-Muro, Abraham; Jacques, Mario; Avelar-González, Francisco J; Labrie, Josée; Tremblay, Yannick D N; Oropeza-Navarro, Ricardo; Guerrero-Barrera, Alma L

    2016-06-27

    Actinobacillus pleuropneumoniae is the etiologic agent of porcine contagious pleuropneumonia, which causes important worldwide economic losses in the swine industry. Several respiratory tract infections are associated with biofilm formation, and A. pleuropneumoniae has the ability to form biofilms in vitro. Biofilms are structured communities of bacterial cells enclosed in a self-produced polymer matrix that are attached to an abiotic or biotic surface. Virtually all bacteria can grow as a biofilm, and multi-species biofilms are the most common form of microbial growth in nature. The goal of this study was to determine the ability of A. pleuropneumoniae to form multi-species biofilms with other bacteria frequently founded in pig farms, in the absence of pyridine compounds (nicotinamide mononucleotide [NMN], nicotinamide riboside [NR] or nicotinamide adenine dinucleotide [NAD]) that are essential for the growth of A. pleuropneumoniae. For the biofilm assay, strain 719, a field isolate of A. pleuropneumoniae serovar 1, was mixed with swine isolates of Streptococcus suis, Bordetella bronchiseptica, Pasteurella multocida, Staphylococcus aureus or Escherichia coli, and deposited in 96-well microtiter plates. Based on the CFU results, A. pleuropneumoniae was able to grow with every species tested in the absence of pyridine compounds in the culture media. Interestingly, A. pleuropneumoniae was also able to form strong biofilms when mixed with S. suis, B. bronchiseptica or S. aureus. In the presence of E. coli, A. pleuropneumoniae only formed a weak biofilm. The live and dead populations, and the matrix composition of multi-species biofilms were also characterized using fluorescent markers and enzyme treatments. The results indicated that poly-N-acetyl-glucosamine remains the primary component responsible for the biofilm structure. In conclusion, A. pleuropneumoniae apparently is able to satisfy the requirement of pyridine compounds through of other swine pathogens by cross-feeding, which enables A. pleuropneumoniae to grow and form multi-species biofilms.

  7. 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.

    PubMed

    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.

  8. Atomic-Resolution Structures of Horse Liver Alcohol Dehydrogenase with NAD[superscript +] and Fluoroalcohols Define Strained Michaelis Complexes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Plapp, Bryce V.; Ramaswamy, S.; Iowa)

    2013-01-16

    Structures of horse liver alcohol dehydrogenase complexed with NAD{sup +} and unreactive substrate analogues, 2,2,2-trifluoroethanol or 2,3,4,5,6-pentafluorobenzyl alcohol, were determined at 100 K at 1.12 or 1.14 {angstrom} resolution, providing estimates of atomic positions with overall errors of 0.02 {angstrom}, the geometry of ligand binding, descriptions of alternative conformations of amino acid residues and waters, and evidence of a strained nicotinamide ring. The four independent subunits from the two homodimeric structures differ only slightly in the peptide backbone conformation. Alternative conformations for amino acid side chains were identified for 50 of the 748 residues in each complex, and Leu-57 andmore » Leu-116 adopt different conformations to accommodate the different alcohols at the active site. Each fluoroalcohol occupies one position, and the fluorines of the alcohols are well-resolved. These structures closely resemble the expected Michaelis complexes with the pro-R hydrogens of the methylene carbons of the alcohols directed toward the re face of C4N of the nicotinamide rings with a C-C distance of 3.40 {angstrom}. The oxygens of the alcohols are ligated to the catalytic zinc at a distance expected for a zinc alkoxide (1.96 {angstrom}) and participate in a low-barrier hydrogen bond (2.52 {angstrom}) with the hydroxyl group of Ser-48 in a proton relay system. As determined by X-ray refinement with no restraints on bond distances and planarity, the nicotinamide rings in the two complexes are slightly puckered (quasi-boat conformation, with torsion angles of 5.9{sup o} for C4N and 4.8{sup o} for N1N relative to the plane of the other atoms) and have bond distances that are somewhat different compared to those found for NAD(P){sup +}. It appears that the nicotinamide ring is strained toward the transition state on the path to alcohol oxidation.« less

  9. Alteration in substrate specificity of horse liver alcohol dehydrogenase by an acyclic nicotinamide analog of NAD(+).

    PubMed

    Malver, Olaf; Sebastian, Mina J; Oppenheimer, Norman J

    2014-11-01

    A new, acyclic NAD-analog, acycloNAD(+) has been synthesized where the nicotinamide ribosyl moiety has been replaced by the nicotinamide (2-hydroxyethoxy)methyl moiety. The chemical properties of this analog are comparable to those of β-NAD(+) with a redox potential of -324mV and a 341nm λmax for the reduced form. Both yeast alcohol dehydrogenase (YADH) and horse liver alcohol dehydrogenase (HLADH) catalyze the reduction of acycloNAD(+) by primary alcohols. With HLADH 1-butanol has the highest Vmax at 49% that of β-NAD(+). The primary deuterium kinetic isotope effect is greater than 3 indicating a significant contribution to the rate limiting step from cleavage of the carbon-hydrogen bond. The stereochemistry of the hydride transfer in the oxidation of stereospecifically deuterium labeled n-butanol is identical to that for the reaction with β-NAD(+). In contrast to the activity toward primary alcohols there is no detectable reduction of acycloNAD(+) by secondary alcohols with HLADH although these alcohols serve as competitive inhibitors. The net effect is that acycloNAD(+) has converted horse liver ADH from a broad spectrum alcohol dehydrogenase, capable of utilizing either primary or secondary alcohols, into an exclusively primary alcohol dehydrogenase. This is the first example of an NAD analog that alters the substrate specificity of a dehydrogenase and, like site-directed mutagenesis of proteins, establishes that modifications of the coenzyme distance from the active site can be used to alter enzyme function and substrate specificity. These and other results, including the activity with α-NADH, clearly demonstrate the promiscuity of the binding interactions between dehydrogenases and the riboside phosphate of the nicotinamide moiety, thus greatly expanding the possibilities for the design of analogs and inhibitors of specific dehydrogenases. Copyright © 2014 Elsevier B.V. All rights reserved.

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

    PubMed

    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 Association, Inc.

  11. Depletion of NAD pool contributes to impairment of endothelial progenitor cell mobilization in diabetes.

    PubMed

    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 EPCs number in healthy individuals. At last, we found that the EPC intracellular NAMPT and NAD(+) levels were reduced in T2DM patients and enhancing NAD pool elevated the circulating blood EPCs number in T2DM patients. Our results indicate that the depletion of NAD pool may contribute to the impairment of EPCs mobilization in diabetic condition, and imply the potential therapeutic value of nicotinamide in the prevention and treatment for cardiovascular complications of diabetes. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Biarylmethoxy Nicotinamides As Novel and Specific Inhibitors of Mycobacterium tuberculosis.

    PubMed

    Kedari, Chaitanya Kumar; Roy Choudhury, Nilanjana; Sharma, Sreevalli; Kaur, Parvinder; Guptha, Supreeth; Panda, Manoranjan; Mukerjee, Kakoli; Ramachandran, Vasanthi; Bandodkar, Balachandra; Ramachandran, Sreekanth; Tantry, Subramanyam J

    2014-05-08

    A whole cell based screening effort on a focused library from corporate collection resulted in the identification of biarylmethoxy nicotinamides as novel inhibitors of M. tuberculosis (Mtu) H37Rv. The series exhibited tangible structure-activity relationships, and during hit to lead exploration, a cellular potency of 100 nM was achieved, which is an improvement of >200-fold from the starting point. The series is very specific to Mtu and noncytotoxic up to 250 μM as measured in the mammalian cell line THP-1 based cytotoxicity assay. This compound class retains its potency on several drug sensitive and single drug resistant clinical isolates, which indicate that the compounds could be acting through a novel mode of action.

  13. A novel cream formulation containing nicotinamide 4%, arbutin 3%, bisabolol 1%, and retinaldehyde 0.05% for treatment of epidermal melasma.

    PubMed

    Crocco, Elisete I; Veasey, John V; Boin, Maria F; Lellis, Rute F; Alves, Renata O

    2015-11-01

    Epidermal melasma is a common hyperpigmentation disorder that can be challenging to treat. Although current treatment options for melasma are limited, topical skin-lightening preparations have widely been used as alternatives to hydroquinone. In this prospective, single-arm, open-label study, treatment of epidermal melasma with a novel cream formulation containing nicotinamide 4%, arbutin 3%, bisabolol 1%, and retinaldehyde 0.05% was associated with reductions in Melasma Area and Severity Index (MASI) scores as well as total melasma surface area as measured by medical imaging software. Treatment outcomes including tolerance and safety profiles as well as patient satisfaction and product appreciation showed this novel cosmetic compound may be valuable in the treatment of epidermal melasma.

  14. Nicotinamide N-methyltransferase expression in SH-SY5Y neuroblastoma and N27 mesencephalic neurones induces changes in cell morphology via ephrin-B2 and Akt signalling

    PubMed Central

    Thomas, M G; Saldanha, M; Mistry, R J; Dexter, D T; Ramsden, D B; Parsons, R B

    2013-01-01

    Nicotinamide N-methyltransferase (NNMT, E.C. 2.1.1.1) N-methylates nicotinamide to produce 1-methylnicotinamide (MeN). We have previously shown that NNMT expression protected against neurotoxin-mediated cell death by increasing Complex I (CxI) activity, resulting in increased ATP synthesis. This was mediated via protection of the NDUFS3 subunit of CxI from degradation by increased MeN production. In the present study, we have investigated the effects of NNMT expression on neurone morphology and differentiation. Expression of NNMT in SH-SY5Y human neuroblastoma and N27 rat mesencephalic dopaminergic neurones increased neurite branching, synaptophysin expression and dopamine accumulation and release. siRNA gene silencing of ephrin B2 (EFNB2), and inhibition of Akt phosphorylation using LY294002, demonstrated that their sequential activation was responsible for the increases observed. Incubation of SH-SY5Y with increasing concentrations of MeN also increased neurite branching, suggesting that the effects of NNMT may be mediated by MeN. NNMT had no significant effect on the expression of phenotypic and post-mitotic markers, suggesting that NNMT is not involved in determining phenotypic fate or differentiation status. These results demonstrate that NNMT expression regulates neurone morphology in vitro via the sequential activation of the EFNB2 and Akt cellular signalling pathways. PMID:23764850

  15. Nicotinamide N-methyltransferase expression in SH-SY5Y neuroblastoma and N27 mesencephalic neurones induces changes in cell morphology via ephrin-B2 and Akt signalling.

    PubMed

    Thomas, M G; Saldanha, M; Mistry, R J; Dexter, D T; Ramsden, D B; Parsons, R B

    2013-06-13

    Nicotinamide N-methyltransferase (NNMT, E.C. 2.1.1.1) N-methylates nicotinamide to produce 1-methylnicotinamide (MeN). We have previously shown that NNMT expression protected against neurotoxin-mediated cell death by increasing Complex I (CxI) activity, resulting in increased ATP synthesis. This was mediated via protection of the NDUFS3 subunit of CxI from degradation by increased MeN production. In the present study, we have investigated the effects of NNMT expression on neurone morphology and differentiation. Expression of NNMT in SH-SY5Y human neuroblastoma and N27 rat mesencephalic dopaminergic neurones increased neurite branching, synaptophysin expression and dopamine accumulation and release. siRNA gene silencing of ephrin B2 (EFNB2), and inhibition of Akt phosphorylation using LY294002, demonstrated that their sequential activation was responsible for the increases observed. Incubation of SH-SY5Y with increasing concentrations of MeN also increased neurite branching, suggesting that the effects of NNMT may be mediated by MeN. NNMT had no significant effect on the expression of phenotypic and post-mitotic markers, suggesting that NNMT is not involved in determining phenotypic fate or differentiation status. These results demonstrate that NNMT expression regulates neurone morphology in vitro via the sequential activation of the EFNB2 and Akt cellular signalling pathways.

  16. Inhibitor of Nicotinamide Phosphoribosyltransferase Sensitizes Glioblastoma Cells to Temozolomide via Activating ROS/JNK Signaling Pathway.

    PubMed

    Feng, Jun; Yan, Peng-Fei; Zhao, Hong-Yang; Zhang, Fang-Cheng; Zhao, Wo-Hua; Feng, Min

    2016-01-01

    Overcoming temozolomide (TMZ) resistance is a great challenge in glioblastoma (GBM) treatment. Nicotinamide phosphoribosyltransferase (NAMPT) is a rate-limiting enzyme in the biosynthesis of nicotinamide adenine dinucleotide and has a crucial role in cancer cell metabolism. In this study, we investigated whether FK866 and CHS828, two specific NAMPT inhibitors, could sensitize GBM cells to TMZ. Low doses of FK866 and CHS828 (5 nM and 10 nM, resp.) alone did not significantly decrease cell viability in U251-MG and T98 GBM cells. However, they significantly increased the antitumor action of TMZ in these cells. In U251-MG cells, administration of NAMPT inhibitors increased the TMZ (100  μ M)-induced apoptosis and LDH release from GBM cells. NAMPT inhibitors remarkably enhanced the activities of caspase-1, caspase-3, and caspase-9. Moreover, NAMPT inhibitors increased reactive oxygen species (ROS) production and superoxide anion level but reduced the SOD activity and total antioxidative capacity in GBM cells. Treatment of NAMPT inhibitors increased phosphorylation of c-Jun and JNK. Administration of JNK inhibitor SP600125 or ROS scavenger tocopherol with TMZ and NAMPT inhibitors substantially attenuated the sensitization of NAMPT inhibitor on TMZ antitumor action. Our data indicate a potential value of NAMPT inhibitors in combined use with TMZ for GBM treatment.

  17. Protein kinase C epsilon regulates mitochondrial pools of Nampt and NAD following resveratrol and ischemic preconditioning in the rat cortex

    PubMed Central

    Morris-Blanco, Kahlilia C; Cohan, Charles H; Neumann, Jake T; Sick, Thomas J; Perez-Pinzon, Miguel A

    2014-01-01

    Preserving mitochondrial pools of nicotinamide adenine dinucleotide (NAD) or nicotinamide phosphoribosyltransferase (Nampt), an enzyme involved in NAD production, maintains mitochondrial function and confers neuroprotection after ischemic stress. However, the mechanisms involved in regulating mitochondrial-localized Nampt or NAD have not been defined. In this study, we investigated the roles of protein kinase C epsilon (PKCɛ) and AMP-activated protein kinase (AMPK) in regulating mitochondrial pools of Nampt and NAD after resveratrol or ischemic preconditioning (IPC) in the cortex and in primary neuronal-glial cortical cultures. Using the specific PKCɛ agonist ψɛRACK, we found that PKCɛ induced robust activation of AMPK in vitro and in vivo and that AMPK was required for PKCɛ-mediated ischemic neuroprotection. In purified mitochondrial fractions, PKCɛ enhanced Nampt levels in an AMPK-dependent manner and was required for increased mitochondrial Nampt after IPC or resveratrol treatment. Analysis of intrinsic NAD autofluorescence using two-photon microscopy revealed that PKCɛ modulated NAD in the mitochondrial fraction. Further assessments of mitochondrial NAD concentrations showed that PKCɛ has a key role in regulating the mitochondrial NAD+/nicotinamide adenine dinucleotide reduced (NADH) ratio after IPC and resveratrol treatment in an AMPK- and Nampt-dependent manner. These findings indicate that PKCɛ is critical to increase or maintain mitochondrial Nampt and NAD after pathways of ischemic neuroprotection in the brain. PMID:24667915

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

    PubMed

    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.

  19. Essential role of Bordetella NadC in a quinolinate salvage pathway for NAD biosynthesis.

    PubMed

    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.

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

    PubMed Central

    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

  1. Nicotinamide Riboside Is a Major NAD+ Precursor Vitamin in Cow Milk.

    PubMed

    Trammell, Samuel Aj; Yu, Liping; Redpath, Philip; Migaud, Marie E; Brenner, Charles

    2016-05-01

    Nicotinamide riboside (NR) is a recently discovered NAD(+) precursor vitamin with a unique biosynthetic pathway. Although the presence of NR in cow milk has been known for more than a decade, the concentration of NR with respect to the other NAD(+) precursors was unknown. We aimed to determine NAD(+) precursor vitamin concentration in raw samples of milk from individual cows and from commercially available cow milk. LC tandem mass spectrometry and isotope dilution technologies were used to quantify NAD(+) precursor vitamin concentration and to measure NR stability in raw and commercial milk. Nuclear magnetic resonance (NMR) spectroscopy was used to test for NR binding to substances in milk. Cow milk typically contained ∼12 μmol NAD(+) precursor vitamins/L, of which 60% was present as nicotinamide and 40% was present as NR. Nicotinic acid and other NAD(+) metabolites were below the limits of detection. Milk from samples testing positive for Staphylococcus aureus contained lower concentrations of NR (Spearman ρ = -0.58, P = 0.014), and NR was degraded by S. aureus Conventional milk contained more NR than milk sold as organic. Nonetheless, NR was stable in organic milk and exhibited an NMR spectrum consistent with association with a protein fraction in skim milk. NR is a major NAD(+) precursor vitamin in cow milk. Control of S. aureus may be important to preserve the NAD(+) precursor vitamin concentration of milk. © 2016 American Society for Nutrition.

  2. Pnc1p-Mediated Nicotinamide Clearance Modifies the Epigenetic Properties of rDNA Silencing in Saccharomyces cerevisiae

    PubMed Central

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

    2008-01-01

    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. PMID:18780747

  3. Repeat dose NRPT (nicotinamide riboside and pterostilbene) increases NAD+ levels in humans safely and sustainably: a randomized, double-blind, placebo-controlled study.

    PubMed

    Dellinger, Ryan W; Santos, Santiago Roel; Morris, Mark; Evans, Mal; Alminana, Dan; Guarente, Leonard; Marcotulli, Eric

    2017-01-01

    NRPT is a combination of nicotinamide riboside (NR), a nicotinamide adenine dinucleotide (NAD +) precursor vitamin found in milk, and pterostilbene (PT), a polyphenol found in blueberries. Here, we report this first-in-humans clinical trial designed to assess the safety and efficacy of a repeat dose of NRPT (commercially known as Basis). NRPT was evaluated in a randomized, double-blind, and placebo-controlled study in a population of 120 healthy adults between the ages of 60 and 80 years. The study consisted of three treatment arms: placebo, recommended dose of NRPT (NRPT 1X), and double dose of NRPT (NRPT 2X). All subjects took their blinded supplement daily for eight weeks. Analysis of NAD + in whole blood demonstrated that NRPT significantly increases the concentration of NAD + in a dose-dependent manner. NAD + levels increased by approximately 40% in the NRPT 1X group and approximately 90% in the NRPT 2X group after 4 weeks as compared to placebo and baseline. Furthermore, this significant increase in NAD + levels was sustained throughout the entire 8-week trial. NAD + levels did not increase for the placebo group during the trial. No serious adverse events were reported in this study. This study shows that a repeat dose of NRPT is a safe and effective way to increase NAD + levels sustainably.

  4. Ligand binding phenomena that pertain to the metabolic function of renalase.

    PubMed

    Beaupre, Brett A; Roman, Joseph V; Hoag, Matthew R; Meneely, Kathleen M; Silvaggi, Nicholas R; Lamb, Audrey L; Moran, Graham R

    2016-12-15

    Renalase catalyzes the oxidation of isomers of β-NAD(P)H that carry the hydride in the 2 or 6 positions of the nicotinamide base to form β-NAD(P) + . This activity is thought to alleviate inhibition of multiple β-NAD(P)-dependent enzymes of primary and secondary metabolism by these isomers. Here we present evidence for a variety of ligand binding phenomena relevant to the function of renalase. We offer evidence of the potential for primary metabolism inhibition with structures of malate dehydrogenase and lactate dehydrogenase bound to the 6-dihydroNAD isomer. The previously observed preference of renalase from Pseudomonas for NAD-derived substrates over those derived from NADP is accounted for by the structure of the enzyme in complex with NADPH. We also show that nicotinamide nucleosides and mononucleotides reduced in the 2- and 6-positions are renalase substrates, but bind weakly. A seven-fold enhancement of acquisition (k red /K d ) for 6-dihydronicotinamide riboside was observed for human renalase in the presence of ADP. However, generally the addition of complement ligands, AMP for mononucleotide or ADP for nucleoside substrates, did not enhance the reductive half-reaction. Non-substrate nicotinamide nucleosides or nucleotides bind weakly suggesting that only β-NADH and β-NADPH compete with dinucleotide substrates for access to the active site. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. A pre-steady state and steady state kinetic analysis of the N-ribosyl hydrolase activity of hCD157.

    PubMed

    Preugschat, Frank; Carter, Luke H; Boros, Eric E; Porter, David J T; Stewart, Eugene L; Shewchuk, Lisa M

    2014-12-15

    hCD157 catalyzes the hydrolysis of nicotinamide riboside (NR) and nicotinic acid riboside (NAR). The release of nicotinamide or nicotinic acid from NR or NAR was confirmed by spectrophotometric, HPLC and NMR analyses. hCD157 is inactivated by a mechanism-based inhibitor, 2'-deoxy-2'-fluoro-nicotinamide arabinoside (fNR). Modification of the enzyme during the catalytic cycle by NR, NAR, or fNR increased the intrinsic protein fluorescence by approximately 50%. Pre-steady state and steady state data were used to derive a minimal kinetic scheme for the hydrolysis of NR. After initial complex formation a reversible step (360 and 30s(-1)) is followed by a slow irreversible step (0.1s(-1)) that defined the rate limiting step, or kcat. The calculated KMapp value for NR in the hydrolytic reaction is 6nM. The values of the kinetic constants suggest that one biological function of cell-surface hCD157 is to bind and slowly hydrolyze NR, possibly converting it to a ligand-activated receptor. Differences in substrate preference between hCD157 and hCD38 were rationalized through a comparison of the crystal structures of the two proteins. This comparison identified several residues in hCD157 (F108 and F173) that can potentially hinder the binding of dinucleotide substrates (NAD+). Copyright © 2014 Elsevier Inc. All rights reserved.

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

    PubMed

    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.

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

    PubMed Central

    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

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

    PubMed

    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.

  9. CD38 Dictates Age-Related NAD Decline and Mitochondrial Dysfunction through an SIRT3-Dependent Mechanism.

    PubMed

    Camacho-Pereira, Juliana; Tarragó, Mariana G; Chini, Claudia C S; Nin, Veronica; Escande, Carlos; Warner, Gina M; Puranik, Amrutesh S; Schoon, Renee A; Reid, Joel M; Galina, Antonio; Chini, Eduardo N

    2016-06-14

    Nicotinamide adenine dinucleotide (NAD) levels decrease during aging and are involved in age-related metabolic decline. To date, the mechanism responsible for the age-related reduction in NAD has not been elucidated. Here we demonstrate that expression and activity of the NADase CD38 increase with aging and that CD38 is required for the age-related NAD decline and mitochondrial dysfunction via a pathway mediated at least in part by regulation of SIRT3 activity. We also identified CD38 as the main enzyme involved in the degradation of the NAD precursor nicotinamide mononucleotide (NMN) in vivo, indicating that CD38 has a key role in the modulation of NAD-replacement therapy for aging and metabolic diseases. Copyright © 2016 Elsevier Inc. All rights reserved.

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

    PubMed

    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 < 0.05). MDA, TOS and NO increased (p < 0.001) in diabetic rats compared with the control group, and decreased in garlic-treated diabetic rats compared with diabetic rats (p < 0.01). The level of TNF-α mRNA did not differ between groups but the TNF-α protein level in diabetic rats was higher than in the control rats (p < 0.01), whereas after treatment with garlic, it was close to the normal level (p < 0.01). These results indicate that garlic extract has hypoglycaemic, antioxidant and anti-inflammatory properties; therefore, it can be useful for the alleviation of diabetic complications.

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

    PubMed

    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, the proapoptotic action of palmitate seems not to be mediated by decreased NAD levels.

  12. Nicotinamide Riboside and Mitochondrial Biogenesis

    ClinicalTrials.gov

    2018-03-15

    Mitochondrial Diseases; Mitochondrial Myopathies; Progressive External Ophthalmoplegia; Progressive Ophthalmoplegia; Progressive; Ophthalmoplegia, External; Mitochondria DNA Deletion; MELAS; Mitochondrial Encephalomyopathy, Lactic Acidosis, and Stroke-Like Episodes; Mitochondrial Encephalopathy, Lactic Acidosis and Stroke-Like Episodes (MELAS Syndrome)

  13. Chem Ed Compacts

    ERIC Educational Resources Information Center

    Wolf, Walter A., Ed.

    1976-01-01

    Presents three activities: (1) the investigation of the purity and stability of nicotinamide and flavin coenzymes; (2) desk-computer fitting of a two-exponential function; and (3) an interesting and inexpensive solubility product experiment for introductory chemistry. (RH)

  14. Effect of ionic strength on the thermodynamic characteristics of complexation between Fe(III) ion and nicotinamide in water-ethanol and water-dimethyl sulfoxide mixtures

    NASA Astrophysics Data System (ADS)

    Gamov, G. A.; Grazhdan, K. V.; Gavrilova, M. A.; Dushina, S. V.; Sharnin, V. A.; Baranski, A.

    2013-06-01

    Solutions of iron(III) perchlorate in water, water-ethanol, and water-dimethyl sulfoxide solvents (x_{H_2 O} = 0.7 and 0.25 mole fractions) at ionic strength values I = 0.1, 0.25, and 0.5 are studied by IR spectroscopy. Analysis of the absorption bands of perchlorate ion shows that it does not participate in association processes. It is demonstrated that in the range of ionic strength values between 0 and 0.5 (NaClO4), it affects neither the results from potentiometric titration to determine the stability constants of the iron(III)-nicotinamide complex nor the thermal effects of complexation determined via direct calorimetry in a binary solvent containing 0.3 mole fractions (m.f.) of a non-aqueous component.

  15. Mannitol and Mannitol Dehydrogenases in Conidia of Aspergillus oryzae

    PubMed Central

    Horikoshi, Koki; Iida, Shigeji; Ikeda, Yonosuke

    1965-01-01

    Horikoshi, Koki (The Institute of Physical and Chemical Research, Tokyo, Japan), Shigeji Iida, and Yonosuke Ikeda. Mannitol and mannitol dehydrogenases in conidia of Aspergillus oryzae. J. Bacteriol. 89:326–330. 1965.—A sugar alcohol was isolated from the conidia of Aspergillus oryzae and identified as d-mannitol. Two types of d-mannitol dehydrogenases, nicotinamide adenine dinucleotide phosphate-linked and nicotinamide adenine dinucleotide-linked, were found in the conidia. Substrate specificities, pH optima, Michaelis-Menton constants, and the effects of inhibitors were studied. d-Mannitol was converted to fructose by the dehydrogenases. Synthesis of d-mannitol dehydrogenases was not observed during germination; the content of d-mannitol decreased at an early stage of germination. It was assumed, therefore, that d-mannitol might be used as the source of endogenous respiration and provide energy for the germination. PMID:14255698

  16. In vitro activity of nicotinamide/antileishmanial drug combinations.

    PubMed

    Gazanion, Elodie; Vergnes, Baptiste; Seveno, Marie; Garcia, Deborah; Oury, Bruno; Ait-Oudhia, Khatima; Ouaissi, Ali; Sereno, Denis

    2011-01-01

    To improve the management of leishmaniasis, new drugs and/or alternative therapeutic strategies are required. Combination therapy of antileishmanial drugs is currently considered as one of the most rational approaches to lower treatment failure rate and limit drug resistance spreading. Nicotinamide (NAm), also known as vitamin B3 that is already is used in human therapy, exerts in vitro antileishmanial activity. Drug combination studies, performed on L. infantum axenic amastigotes, revealed that NAm significantly improves the antileishmanial activity of trivalent antimony in a synergistic manner while it shows additive activity with amphotericin B and slightly antagonizes pentamidine activity. NAm also significantly increases the toxicity of pentavalent antimony against the intracellular forms of L. infantum, L. amazonensis and L. braziliensis. The potential of NAm to be used as adjuvant during leishmaniasis chemotherapy is further discussed. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  17. Localization and phosphorylation of Plasmodium falciparum nicotinamide/nicotinate mononucleotide adenylyltransferase (PfNMNAT) in intraerythrocytic stages.

    PubMed

    Nieto, Carlos A; Sánchez, Lina M; Sánchez, Diana M; Díaz, Gonzalo J; Ramírez, María H

    2018-04-11

    Nicotinamide adenine dinucleotide (NAD+) is an essential molecule in the energy metabolism of living beings, and it has various cellular functions. The main enzyme in the biosynthesis of this nucleotide is nicotinamide/nicotinate mononucleotide adenylyltransferase (NMNAT, EC 2.7.7.1/18) because it is the convergence point for all known biosynthetic pathways. NMNATs have divergences in both the number of isoforms detected and their distribution, depending on the organism. In the laboratory of basic research in biochemistry (LIBBIQ: acronym in Spanish) the NMNATs of protozoan parasites (Leishmania braziliensis, Plasmodium falciparum, Trypanosoma cruzi, and Giardia duodenalis) have been studied, analysing their catalytic properties through the use of proteins. Recombinants and their cellular distribution essentially. In 2014, O'Hara et al. determined the cytoplasmic localization of NMNAT of P. falciparum, using a transgene coupled to GFP, however, the addition of labels to the study protein can modify several of its characteristics, including its sub-cellular localization. This study confirms the cytoplasmic localization of this protein in the parasite through recognition of the endogenous protein in the different stages of the asexual life cycle. Additionally, the study found that PfNMNAT could be a phosphorylation target at serine, tyrosine and threonine residues, and it shows variations during the asexual life cycle. These experiments confirmed that the parasite is situated in the cytoplasm, fulfilling the required functions of NAD+ in this compartment, the PfNMNAT is regulated in post-transcription processes, and can be regulated by phosphorylation in its residues.

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

    PubMed

    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.

  19. Salicylate Treatment Improves Age-Associated Vascular Endothelial Dysfunction: Potential Role of Nuclear Factor κB and Forkhead Box O Phosphorylation

    PubMed Central

    Durrant, Jessica R.; Connell, Melanie L.; Folian, Brian J.; Donato, Anthony J.; Seals, Douglas R.

    2011-01-01

    We hypothesized that I kappa B kinase (IKK)-mediated nuclear factor kappa B and forkhead BoxO3a phosphorylation will be associated with age-related endothelial dysfunction. Endothelium-dependent dilation and aortic protein expression/phosphorylation were determined in young and old male B6D2F1 mice and old mice treated with the IKK inhibitor, salicylate. IKK activation was greater in old mice and was associated with greater nitrotyrosine and cytokines. Endothelium-dependent dilation, nitric oxide (NO), and endothelial NO synthase phosphorylation were lower in old mice. Endothelium-dependent dilation and NO bioavailability were restored by a superoxide dismutase mimetic. Nuclear factor kappa B and forkhead BoxO3a phosphorylation were greater in old and were associated with increased expression/activity of nicotinamide adenine dinucleotide phosphate oxidase and lower manganese superoxide dismutase expression. Salicylate lowered IKK phosphorylation and reversed age-associated changes in nitrotyrosine, endothelium-dependent dilation, NO bioavailability, endothelial NO synthase, nuclear factor kappa B and forkhead BoxO3a phosphorylation, nicotinamide adenine dinucleotide phosphate oxidase, and manganese superoxide dismutase. Increased activation of IKK with advancing age stimulates nuclear factor kappa B and inactivates forkhead BoxO3a. This altered transcription factor activation contributes to a pro-inflammatory/pro-oxidative arterial phenotype that is characterized by increased cytokines and nicotinamide adenine dinucleotide phosphate oxidase and decreased manganese superoxide dismutase leading to oxidative stress-mediated endothelial dysfunction. PMID:21303813

  20. Effect of the Polyphenol Rich Ethyl Acetate Fraction from the Leaves of Lycium chinenseMill. on Oxidative Stress, Dyslipidemia, and Diabetes Mellitus in Streptozotocin-Nicotinamide Induced Diabetic Rats.

    PubMed

    Olatunji, Opeyemi J; Chen, Hongxia; Zhou, Yifeng

    2017-10-01

    Lycium chinenseMill., popularly known as boxthorn, is a plant that is traditionally used for treating night sweat, cough, inflammation and diabetes mellitus. However, the leaves have received little or no attention despite their potentials as a potent therapeutic agent. This study was aimed at investigating the hypoglycemic and hypolipidemic effects of the polyphenols-rich ethyl acetate fraction from the leaves of Lycium chinenseMill. on streptozotocin-nicotinamide induced diabetic rats. The ethyl acetate fraction (LFE) was selected and orally gavaged at 100, 200, and 400 mg/kg dose to streptozotocin (STZ)-nicotinamide induced diabetic rats. The rats' body weight, fasting blood glucose (FBG), lipid profile and oxidative stress markers were evaluated after the treatment period. Treatment with LFE resulted in a significant decrease in the FBG level, altered lipid profiles, and reduced the activities of the enzymes alkaline phosphatase (ALP), aspartate transaminase (AST), alanine transaminase (ALT) in the treated diabetic rats. Furthermore, LFE significantly elevated the antioxidant status (superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities) and reducing malondialdehyde (MDA) levels in the treated rats. The present study has revealed that L. chinenseMill. possess anti-hyperglycemic and anti-hyperlipidemic properties which is mediated through modulation of oxidative stress and polyphenolics might be responsible for the action. © 2017 Wiley-VHCA AG, Zurich, Switzerland.

  1. Identification of novel resistance mechanisms to NAMPT inhibition via the de novo NAD+ biosynthesis pathway and NAMPT mutation.

    PubMed

    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.

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

    PubMed

    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.

  3. Eliciting the mitochondrial unfolded protein response by nicotinamide adenine dinucleotide repletion reverses fatty liver disease in mice

    PubMed Central

    Gariani, Karim; Menzies, Keir J.; Ryu, Dongryeol; Wegner, Casey J.; Wang, Xu; Ropelle, Eduardo R.; Moullan, Norman; Zhang, Hongbo; Perino, Alessia; Lemos, Vera; Kim, Bohkyung; Park, Young‐Ki; Piersigilli, Alessandra; Pham, Tho X.; Yang, Yue; Ku, Chai Siah; Koo, Sung I.; Fomitchova, Anna; Cantó, Carlos; Schoonjans, Kristina; Sauve, Anthony A.

    2015-01-01

    With no approved pharmacological treatment, nonalcoholic fatty liver disease (NAFLD) is now the most common cause of chronic liver disease in Western countries and its worldwide prevalence continues to increase along with the growing obesity epidemic. Here, we show that a high‐fat high‐sucrose (HFHS) diet, eliciting chronic hepatosteatosis resembling human fatty liver, lowers hepatic nicotinamide adenine dinucleotide (NAD+) levels driving reductions in hepatic mitochondrial content, function, and adenosine triphosphate (ATP) levels, in conjunction with robust increases in hepatic weight, lipid content, and peroxidation in C57BL/6J mice. To assess the effect of NAD+ repletion on the development of steatosis in mice, nicotinamide riboside, a precursor of NAD+ biosynthesis, was added to the HFHS diet, either as a preventive strategy or as a therapeutic intervention. We demonstrate that NR prevents and reverts NAFLD by inducing a sirtuin (SIRT)1‐ and SIRT3‐dependent mitochondrial unfolded protein response, triggering an adaptive mitohormetic pathway to increase hepatic β‐oxidation and mitochondrial complex content and activity. The cell‐autonomous beneficial component of NR treatment was revealed in liver‐specific Sirt1 knockout mice (Sirt1hep−/−), whereas apolipoprotein E‐deficient mice (Apoe −/−) challenged with a high‐fat high‐cholesterol diet affirmed the use of NR in other independent models of NAFLD. Conclusion: Our data warrant the future evaluation of NAD+ boosting strategies to manage the development or progression of NAFLD. (Hepatology 2016;63:1190–1204) PMID:26404765

  4. Tissue-specific regulation of sirtuin and nicotinamide adenine dinucleotide biosynthetic pathways identified in C57Bl/6 mice in response to high-fat feeding.

    PubMed

    Drew, Janice E; Farquharson, Andrew J; Horgan, Graham W; Williams, Lynda M

    2016-11-01

    The sirtuin (SIRT)/nicotinamide adenine dinucleotide (NAD) system is implicated in development of type 2 diabetes (T2D) and diet-induced obesity, a major risk factor for T2D. Mechanistic links have not yet been defined. SIRT/NAD system gene expression and NAD/NADH levels were measured in liver, white adipose tissue (WAT) and skeletal muscle from mice fed either a low-fat diet or high-fat diet (HFD) for 3 days up to 16 weeks. An in-house custom-designed multiplex gene expression assay assessed all 7 mouse SIRTs (SIRT1-7) and 16 enzymes involved in conversion of tryptophan, niacin, nicotinamide riboside and metabolic precursors to NAD. Significantly altered transcription was correlated with body weight, fat mass, plasma lipids and hormones. Regulation of the SIRT/NAD system was associated with early (SIRT4, SIRT7, NAPRT1 and NMNAT2) and late phases (NMNAT3, NMRK2, ABCA1 and CD38) of glucose intolerance. TDO2 and NNMT were identified as markers of HFD consumption. Altered regulation of the SIRT/NAD system in response to HFD was prominent in liver compared with WAT or muscle. Multiple components of the SIRTs and NAD biosynthetic enzymes network respond to consumption of dietary fat. Novel molecular targets identified above could direct strategies for dietary/therapeutic interventions to limit metabolic dysfunction and development of T2D. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Recognition of Nucleoside Monophosphate Substrates by Haemophilus influenzae Class C Acid Phosphatase

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Singh, Harkewal; Schuermann, Jonathan P.; Reilly, Thomas J.

    2010-12-08

    The e (P4) phosphatase from Haemophilus influenzae functions in a vestigial NAD{sup +} utilization pathway by dephosphorylating nicotinamide mononucleotide to nicotinamide riboside. P4 is also the prototype of class C acid phosphatases (CCAPs), which are nonspecific 5{prime},3{prime}-nucleotidases localized to the bacterial outer membrane. To understand substrate recognition by P4 and other class C phosphatases, we have determined the crystal structures of a substrate-trapping mutant P4 enzyme complexed with nicotinamide mononucleotide, 5{prime}-AMP, 3{prime}-AMP, and 2{prime}-AMP. The structures reveal an anchor-shaped substrate-binding cavity comprising a conserved hydrophobic box that clamps the nucleotide base, a buried phosphoryl binding site, and three solvent-filled pocketsmore » that contact the ribose and the hydrogen-bonding edge of the base. The span between the hydrophobic box and the phosphoryl site is optimal for recognizing nucleoside monophosphates, explaining the general preference for this class of substrate. The base makes no hydrogen bonds with the enzyme, consistent with an observed lack of base specificity. Two solvent-filled pockets flanking the ribose are key to the dual recognition of 5{prime}-nucleotides and 3{prime}-nucleotides. These pockets minimize the enzyme's direct interactions with the ribose and provide sufficient space to accommodate 5{prime} substrates in an anti conformation and 3{prime} substrates in a syn conformation. Finally, the structures suggest that class B acid phosphatases and CCAPs share a common strategy for nucleotide recognition.« less

  6. In vivo assessment of antihyperglycemic and antioxidant activity from oil of seeds of brassica nigra in streptozotocin induced diabetic rats.

    PubMed

    Kumar, Manoj; Sharma, Sunil; Vasudeva, Neeru

    2013-01-01

    This study was made to investigate the antihyperglycemic and antioxidant potential of oil of seeds of Brassica nigra (BNO) in streptozotocin -nicotinamide (STZ) induced type 2 diabetic rats. BNO was orally administered to diabetic rats to study its effect in both acute and chronic antihyperglycemic study. The body weight, oral glucose tolerance test and biochemical parameters viz. glucose level, insulin level, liver glycogen content, glycosylated hemoglobin and antioxidant parameters were estimated for all treated groups and compared against diabetic control group. Administration of BNO at a dose 500 mg/kg and 1000 mg/kg body weight p.o. to STZ diabetic rats showed reduction in blood glucose level from 335 mg/dl to 280 mg/dl at 4th h and from 330 mg/dl to 265 mg/dl respectively which was found significant (p<0.01) as compared with diabetic control. BNO (500 mg/kg and 1000 mg/kg) and glibenclamide (0.6 mg/kg) in respective groups of diabetic animals administered for 28 days reduced the blood glucose level in streptozotocin-nicotinamide induced diabetic rats. There was significant increase in body weight, liver glycogen content, plasma insulin level and decrease in glycosylated hemoglobin in test groups as compared to control group. In vivo antioxidant studies on STZ-nicotinamide induced diabetic rat's revealed decreased malondialdehyde (MDA) and increased reduced glutathione (GSH). Thus the results showed that the oil of seeds of Brassica nigra has significant antihyperglycemic and antioxidant activity.

  7. Multiple isotope effects with alternative dinucleotide substrates as a probe of the malic enzyme reaction

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Weiss, P.M.; Urbauer, J.L.; Cleland, W.W.

    1991-06-11

    Deuterium isotope effects and {sup 13}C isotope effects with deuterium- and protium-labeled malate have been obtained for both NAD- and NADP-malic enzymes by using a variety of alternative dinucleotide substrates. With nicotinamide-containing dinucleotides as the oxidizing substrate, the {sup 13}C effect decreases when deuterated malate is the substrate compared to the value obtained with protium-labeled malate. These data are consistent with a stepwise chemical mechanism in which hydride transfer precedes decarboxylation of the oxalacetate intermediate as previously proposed. When dinucleotide substrates such as thio-NAD, 3-nicotinamide rings are used, the {sup 13}C effect increases when deuterated malate is the substrate comparedmore » to the value obtained with protium-labeled malate. These data, at face value, are consistent with a change in mechanism from stepwise to concerted for the oxidative decarboxylation portion of the mechanism. However, the increase in the deuterium isotope effect from 1.5 to 3 with a concomitant decrease in the {sup 13}C isotope effect from 1.034 to 1.003 as the dinucleotide substrate is changed suggests that the reaction may still be stepwise with the non-nicotinamide dinucleotides. A more likely explanation is that a {beta}-secondary {sup 13}C isotope effect accompanies hydride transfer as a result of hyperconjugation of the {beta}-carboxyl of malate as the transition state for the hydride transfer step is approached.« less

  8. NAD deamidation "a new reaction" by an enzyme from Aspergillus terreus DSM 826.

    PubMed

    Elzainy, Tahany A; Ali, Thanaa H

    2005-02-01

    NAD deamidation is a non-previously recognized reaction. This reaction has been found to be catalyzed by extracts of Aspergillus terreus DSM 826. Conversion of NAD to the biosynthetic intermediate, deamido NAD, by these extracts, at the optimum pH and temperature did not exceed about 55 of the amount of the substrate added. Completion of the reaction was achieved when the extracts were pre-heated at 50 degrees C for 15 min in absence of the substrate. In a very similar manner, the extracts catalyzed hydrolytic cleavage of the amide linkages of different biomolecules such as nicotinamide, nicotinamide riboside, nicotinamide mononucleotide, L-glutamine, L-asparagine and acetamide. Polyacrylamide was also deamidated under the same conditions. In addition, complete dephosphorylation of the dinucleotide molecule was also effected by the same extracts. Separation of the NAD deamidating enzyme from the NAD dephosphorylating enzyme was achieved on using either DEAE - Sephadex A-25 or Sephadex G-200 column chromatography. The obtained phosphohydrolase-free-deamidase showed optimum activity at pH 8 of 0.1 M phosphate buffer and 50 degrees C. It exhibited broad substrate specificity and hyperbolic substrate saturation kinetics. It was isosterically inhibited by the product of its activity and this inhibition was prevented by heating the extracts at 50 degrees C for 15 min. Its activity was not affected in presence of sodium fluoride, partially inhibited in presence of magnesium chloride and was retained in the freezer for some months.

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

    NASA Astrophysics Data System (ADS)

    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.

  10. Better than Nature: Nicotinamide Biomimetics That Outperform Natural Coenzymes.

    PubMed

    Knaus, Tanja; Paul, Caroline E; Levy, Colin W; de Vries, Simon; Mutti, Francesco G; Hollmann, Frank; Scrutton, Nigel S

    2016-01-27

    The search for affordable, green biocatalytic processes is a challenge for chemicals manufacture. Redox biotransformations are potentially attractive, but they rely on unstable and expensive nicotinamide coenzymes that have prevented their widespread exploitation. Stoichiometric use of natural coenzymes is not viable economically, and the instability of these molecules hinders catalytic processes that employ coenzyme recycling. Here, we investigate the efficiency of man-made synthetic biomimetics of the natural coenzymes NAD(P)H in redox biocatalysis. Extensive studies with a range of oxidoreductases belonging to the "ene" reductase family show that these biomimetics are excellent analogues of the natural coenzymes, revealed also in crystal structures of the ene reductase XenA with selected biomimetics. In selected cases, these biomimetics outperform the natural coenzymes. "Better-than-Nature" biomimetics should find widespread application in fine and specialty chemicals production by harnessing the power of high stereo-, regio-, and chemoselective redox biocatalysts and enabling reactions under mild conditions at low cost.

  11. INFLUENCE OF TOTAL BODY X-IRRADIATION ON THE LEVELS OF CREATINE PHOSPHATE, INORGANIC PHOSPHORUS AND ATP IN MUSCLE AND ON THE LEVELS OF CREATINE, CREATININE, N'-METHYL-NICOTINAMIDE AND NITROGEN IN URINE

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kumta, U.S.; Gurnani, S.U.; Sahasrabudhe, M.B.

    1957-09-01

    The influence of total-body irradiation on the levels of creatine phosphate (CP), adenosine triphosphate (ATP) and inorganic phosphorus (IP) in muscle has been investigated in rats. CP and ATP levels decrease by about 33% while those of 1P increase 4 times in irradiated rats. Studies on the influence of irradiation on the excretion of creatine, creatinine, and N'-methyl- nicotinamide in urine show that the excretion of creatine and N'-methyl- nlcotinamide is increased two-fold while that of creatinine is increased by 160%. It is suggested that the low levels of creatine phosphate are probably due to an impairment in the phosphorylationmore » of creatine or due to an adaptive breakdown of creatine phosphate leading to increased excretion of creatine and creatinine. (auth)« less

  12. Studying Catabolism of Protein ADP-Ribosylation.

    PubMed

    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.

  13. Paper microfluidic-based enzyme catalyzed double microreactor.

    PubMed

    Ferrer, Ivonne M; Valadez, Hector; Estala, Lissette; Gomez, Frank A

    2014-08-01

    We describe a paper microfluidic-based enzyme catalyzed double microreactor assay using fluorescent detection. Here, solutions of lactate dehydrogenase (LDH) and diaphorase (DI) were directly spotted onto the microfluidic paper-based analytical device (μPAD). Samples containing lactic acid, resazurin, and nicotinamide adenine dinucleotide oxidized form (NAD(+) ), potassium chloride (KCl), and BSA, in MES buffer were separately spotted onto the μPAD and MES buffer flowed through the device. A cascade reaction occurs upon the sample spot overlapping with LDH to form pyruvate and nicotinamide adenine dinucleotide reduced form (NADH). Subsequently, NADH is used in the conversion of resazurin to fluorescent resorufin by DI. The μPAD avoids the need of surface functionalization or enzyme immobilization steps. These microreactor devices are low cost and easy to fabricate and effect reaction based solely on buffer capillary action. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Binary and ternary cocrystals of sulfa drug acetazolamide with pyridine carboxamides and cyclic amides

    PubMed Central

    Bolla, Geetha; Nangia, Ashwini

    2016-01-01

    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). PMID:27006778

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

    NASA Astrophysics Data System (ADS)

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

    2016-09-01

    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.

  16. Adipose tissue NAD+ biology in obesity and insulin resistance: From mechanism to therapy.

    PubMed

    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.

  17. The human NAD metabolome: Functions, metabolism and compartmentalization

    PubMed Central

    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

  18. Reduction of mitomycin C is catalysed by human recombinant NRH:quinone oxidoreductase 2 using reduced nicotinamide adenine dinucleotide as an electron donating co-factor

    PubMed Central

    Jamieson, D; Tung, A T Y; Knox, R J; Boddy, A V

    2006-01-01

    NRH:Quinone Oxidoreductase 2 (NQO2) has been described as having no enzymatic activity with nicotinamide adenine dinucleotide (NADH) or NADPH as electron donating cosubstrates. Mitomycin C (MMC) is both a substrate for and a mechanistic inhibitor of the NQO2 homologue NQO1. NRH:quinone oxidoreductase 2 catalysed the reduction of MMC at pH 5.8 with NADH as a co-factor. This reaction results in species that inhibit the NQO2-mediated metabolism of CB1954. In addition, MMC caused an increase in DNA cross-links in a cell line transfected to overexpress NQO2 to an extent comparable to that observed with an isogenic NQO1-expressing cell line. These data indicate that NQO2 may contribute to the metabolism of MMC to cytotoxic species. PMID:17031400

  19. NAD⁺ repletion improves mitochondrial and stem cell function and enhances life span in mice.

    PubMed

    Zhang, Hongbo; Ryu, Dongryeol; Wu, Yibo; Gariani, Karim; Wang, Xu; Luan, Peiling; D'Amico, Davide; Ropelle, Eduardo R; Lutolf, Matthias P; Aebersold, Ruedi; Schoonjans, Kristina; Menzies, Keir J; Auwerx, Johan

    2016-06-17

    Adult stem cells (SCs) are essential for tissue maintenance and regeneration yet are susceptible to senescence during aging. We demonstrate the importance of the amount of the oxidized form of cellular nicotinamide adenine dinucleotide (NAD(+)) and its effect on mitochondrial activity as a pivotal switch to modulate muscle SC (MuSC) senescence. Treatment with the NAD(+) precursor nicotinamide riboside (NR) induced the mitochondrial unfolded protein response and synthesis of prohibitin proteins, and this rejuvenated MuSCs in aged mice. NR also prevented MuSC senescence in the mdx (C57BL/10ScSn-Dmd(mdx)/J) mouse model of muscular dystrophy. We furthermore demonstrate that NR delays senescence of neural SCs and melanocyte SCs and increases mouse life span. Strategies that conserve cellular NAD(+) may reprogram dysfunctional SCs and improve life span in mammals. Copyright © 2016, American Association for the Advancement of Science.

  20. Synthesis of new 2-substituted pyrido[2,3-d]pyrimidin-4(1H)-ones and their antibacterial activity.

    PubMed

    Lakshmi Narayana, B; Ram Rao, A Raghu; Shanthan Rao, P

    2009-03-01

    2-Substituted-5,7-dimethyl pyrido[2,3-d]pyrimidin-4(1H)-ones (8) were synthesized by oxidation of 2-substituted-5,7-dimethyl dihydropyrido[2,3-d]pyrimidin-4(1H)-ones (7) which were in turn prepared from 2-amino-4,6-dimethyl nicotinamide (5) and substituted aryl aldehydes (6). 2-Amino-4,6-dimethyl nicotinamide (5) was prepared from ethyl cyanoacetate (1) via malonamamidine hydrochloride (3). The compounds were characterized by IR, NMR, MS and elemental analyses. Compounds 7 and 8 were screened for antibacterial activity against gram positive and gram negative bacteria. Dehydrogenated compounds (8) showed less antibacterial activity than the compounds 7. Among all the test compounds screened for antibacterial activity 7c (1.25 microg/ml) showed greater activity. All the synthesized compounds were found inactive when screened for antifungal activity at the concentration of 200 microg/ml.

  1. Investigation of the Ionization Mechanism of NAD+/NADH-Modified Gold Electrodes in ToF-SIMS Analysis.

    PubMed

    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.

  2. Binary and ternary cocrystals of sulfa drug acetazolamide with pyridine carboxamides and cyclic amides.

    PubMed

    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).

  3. General approach to reversing ketol-acid reductoisomerase cofactor dependence from NADPH to NADH

    DOE PAGES

    Brinkmann-Chen, Sabine; Flock, Tilman; Cahn, Jackson K. B.; ...

    2013-06-17

    To date, efforts to switch the cofactor specificity of oxidoreductases from nicotinamide adenine dinucleotide phosphate (NADPH) to nicotinamide adenine dinucleotide (NADH) have been made on a case-by-case basis with varying degrees of success. Here we present a straightforward recipe for altering the cofactor specificity of a class of NADPH-dependent oxidoreductases, the ketol-acid reductoisomerases (KARIs). Combining previous results for an engineered NADH-dependent variant of Escherichia coli KARI with available KARI crystal structures and a comprehensive KARI-sequence alignment, we identified key cofactor specificity determinants and used this information to construct five KARIs with reversed cofactor preference. Additional directed evolution generated two enzymesmore » having NADH-dependent catalytic efficiencies that are greater than the wild-type enzymes with NADPH. As a result, high-resolution structures of a wild-type/variant pair reveal the molecular basis of the cofactor switch.« less

  4. Orofacial inflammatory pain affects the expression of MT1 and NADPH-d in rat caudal spinal trigeminal nucleus and trigeminal ganglion

    PubMed Central

    Huang, Fang; He, Hongwen; Fan, Wenguo; Liu, Yongliang; Zhou, Hongyu; Cheng, Bin

    2013-01-01

    Very little is known about the role of melatonin in the trigeminal system, including the function of melatonin receptor 1. In the present study, adult rats were injected with formaldehyde into the right vibrissae pad to establish a model of orofacial inflammatory pain. The distribution of melatonin receptor 1 and nicotinamide adenine dinucleotide phosphate diaphorase in the caudal spinal trigeminal nucleus and trigeminal ganglion was determined with immunohistochemistry and histochemistry. The results show that there are significant differences in melatonin receptor 1 expression and nicotinamide adenine dinucleotide phosphate diaphorase expression in the trigeminal ganglia and caudal spinal nucleus during the early stage of orofacial inflammatory pain. Our findings suggest that when melatonin receptor 1 expression in the caudal spinal nucleus is significantly reduced, melatonin's regulatory effect on pain is attenuated. PMID:25206619

  5. 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.

    PubMed

    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.

  6. Antitumor effect of combined NAMPT and CD73 inhibition in an ovarian cancer model

    PubMed Central

    Magnone, Mirko; Zamporlini, Federica; Emionite, Laura; Sturla, Laura; Bianchi, Giovanna; Vigliarolo, Tiziana; Nahimana, Aimable; Nencioni, Alessio; Raffaelli, Nadia; Bruzzone, Santina

    2016-01-01

    Nicotinamide phosphoribosyltransferase (NAMPT) is a crucial enzyme in the biosynthesis of intracellular NAD+. NAMPT inhibitors have potent anticancer activity in several preclinical models by depleting NAD+ and ATP levels. Recently, we demonstrated that CD73 enables the utilization of extracellular NAD+/nicotinamide mononucleotide (NMN) by converting them to Nicotinamide riboside (NR), which can cross the plasmamembrane and fuel intracellular NAD+ biosynthesis in human cells. These processes are herein confirmed to also occur in a human ovarian carcinoma cell line (OVCAR-3), by means of CD73 or NRK1 specific silencing. Next, we investigated the anti-tumor activity of the simultaneous inhibition of NAMPT (with FK866) and CD73 (with α, β-methylene adenosine 5′-diphosphate, APCP), in an in vivo human ovarian carcinoma model. Interestingly, the combined therapy was found to significantly decrease intratumor NAD+, NMN and ATP levels, compared with single treatments. In addition, the concentration of these nucleotides in ascitic exudates was more remarkably reduced in animals treated with both FK866 and APCP compared with single treatments. Importantly, tumors treated with FK866 in combination with APCP contained a statistically significant lower proportion of Ki67 positive proliferating cells and a higher percentage of necrotic area. Finally, a slight but significant increase in animal survival in response to the combined therapy, compared to the single agents, could be demonstrated. Our results indicate that the pharmacological inhibition of CD73 enzymatic activity could be considered as a means to potentiate the anti-cancer effects of NAMPT inhibitors. PMID:26658104

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

    PubMed Central

    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. PMID:29491854

  8. Inhibition of NAD glycohydrolase and ADP-ribosyl transferases by carbocyclic analogues of oxidized nicotinamide adenine dinucleotide.

    PubMed

    Slama, J T; Simmons, A M

    1989-09-19

    Analogues of oxidized nicotinamide adenine dinucleotide (NAD+) in which a 2,3-dihydroxycyclopentane ring replaces the beta-D-ribonucleotide ring of the nicotinamide riboside moiety of NAD+ have recently been synthesized [Slama, J. T., & Simmons, A. M. (1988) Biochemistry 27, 183]. Carbocyclic NAD+ analogues have been shown to inhibit NAD glycohydrolases and ADP-ribosyl transferases such as cholera toxin A subunit. In this study, the diastereomeric mixture of dinucleotides was separated, and the inhibitory capacity of each of the purified diastereomers was defined. The NAD+ analogue in which the D-dihydroxycyclopentane is substituted for the D-ribose is designated carba-NAD and was demonstrated to be a poor inhibitor of the Bungarus fasciatus venom NAD glycohydrolase. The diastereomeric dinucleotide pseudo-carbocyclic-NAD (psi-carba-NAD), containing L-dihydroxycyclopentane in place of the D-ribose of NAD+, was shown, however, to be a potent competitive inhibitor of the venom NAD glycohydrolase with an inhibitor dissociation constant (Ki) of 35 microM. This was surprising since psi-carba-NAD contains the carbocyclic analogue of the unnatural L-ribotide and was therefore expected to be a biologically inactive diastereomer. psi-Carba-NAD also competitively inhibited the insoluble brain NAD glycohydrolase from cow (Ki = 6.7 microM) and sheep (Ki = 31 microM) enzyme against which carba-NAD is ineffective. Sensitivity to psi-carba-NAD was found to parallel sensitivity to inhibition by isonicotinic acid hydrazide, another NADase inhibitor. psi-Carba-NAD is neither a substrate for nor an inhibitor of alcohol dehydrogenase, whereas carba-NAD is an efficient dehydrogenase substrate.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Hepatic NAD(+) deficiency as a therapeutic target for non-alcoholic fatty liver disease in ageing.

    PubMed

    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.

  10. Solubility enhancement of a bisnaphthalimide tumoricidal agent, DMP 840, through complexation.

    PubMed

    Raghavan, K S; Nemeth, G A; Gray, D B; Hussain, M A

    1996-10-01

    The purpose of this research was to enhance the aqueous solubility of DMP 840 by complexation with water-soluble and nontoxic agents, and to understand the nature of the interactions involved in complex formation using nuclear magnetic resonance (1H-NMR). The solubility of DMP 840 in water, saline, acetate buffers, and cosolvent mixtures was determined by high-performance liquid chromatography, and the effect of nicotinamide and pyridoxine concentrations on the solubility of DMP 840 was examined by the phase solubility method. 1H-NMR spectra were acquired in deuterated acetate buffer at 400 MHz on a Varian Unity-400 spectrometer. The aqueous solubility of DMP 840 was sensitive to the presence of chloride and acetate anions in solution, and did not improve in the presence of cosolvents. The use of the nontoxic and water-soluble complex-forming agents nicotinamide and pyridoxine, however, resulted in a linear increase in the aqueous solubility of DMP 840 with both ligands. The solubilization appears to be due to formation of 1:1 complexes between DMP 840 and the bioorganic ligands. The complexation constants were 15.57 M-1 for the DMP 840:nicotinamide complex and 13.36 M-1 for the DMP 840:pyridoxine complex. The NMR results indicate that the interaction is a result of vertical or plane-to-plane stacking and the complexation constants were in agreement with that obtained by phase solubility. The results suggest that the aqueous solubility of a poorly water soluble drug substance such as DMP 840 can be significantly enhanced by its complexation with water-soluble and nontoxic agents.

  11. Perinatal asphyxia: CNS development and deficits with delayed onset

    PubMed Central

    Herrera-Marschitz, Mario; Neira-Pena, Tanya; Rojas-Mancilla, Edgardo; Espina-Marchant, Pablo; Esmar, Daniela; Perez, Ronald; Muñoz, Valentina; Gutierrez-Hernandez, Manuel; Rivera, Benjamin; Simola, Nicola; Bustamante, Diego; Morales, Paola; Gebicke-Haerter, Peter J.

    2013-01-01

    Perinatal asphyxia constitutes a prototype of obstetric complications occurring when pulmonary oxygenation is delayed or interrupted. The primary insult relates to the duration of the period lacking oxygenation, leading to death if not re-established. Re-oxygenation leads to a secondary insult, related to a cascade of biochemical events required for restoring proper function. Perinatal asphyxia interferes with neonatal development, resulting in long-term deficits associated to mental and neurological diseases with delayed clinical onset, by mechanisms not yet clarified. In the experimental scenario, the effects observed long after perinatal asphyxia have been explained by overexpression of sentinel proteins, such as poly(ADP-ribose) polymerase-1 (PARP-1), competing for NAD+ during re-oxygenation, leading to the idea that sentinel protein inhibition constitutes a suitable therapeutic strategy. Asphyxia induces transcriptional activation of pro-inflammatory factors, in tandem with PARP-1 overactivation, and pharmacologically induced PARP-1 inhibition also down-regulates the expression of proinflammatory cytokines. Nicotinamide has been proposed as a suitable PARP-1 inhibitor. Its effect has been studied in an experimental model of global hypoxia in rats. In that model, the insult is induced by immersing rat fetus into a water bath for various periods of time. Following asphyxia, the pups are delivered, treated, and nursed by surrogate dams, pending further experiments. Nicotinamide rapidly distributes into the brain following systemic administration, reaching steady state concentrations sufficient to inhibit PARP-1 activity for several hours, preventing several of the long-term consequences of perinatal asphyxia, supporting the idea that nicotinamide constitutes a lead for exploring compounds with similar or better pharmacological profiles. PMID:24723845

  12. Eliciting the mitochondrial unfolded protein response by nicotinamide adenine dinucleotide repletion reverses fatty liver disease in mice.

    PubMed

    Gariani, Karim; Menzies, Keir J; Ryu, Dongryeol; Wegner, Casey J; Wang, Xu; Ropelle, Eduardo R; Moullan, Norman; Zhang, Hongbo; Perino, Alessia; Lemos, Vera; Kim, Bohkyung; Park, Young-Ki; Piersigilli, Alessandra; Pham, Tho X; Yang, Yue; Ku, Chai Siah; Koo, Sung I; Fomitchova, Anna; Cantó, Carlos; Schoonjans, Kristina; Sauve, Anthony A; Lee, Ji-Young; Auwerx, Johan

    2016-04-01

    With no approved pharmacological treatment, nonalcoholic fatty liver disease (NAFLD) is now the most common cause of chronic liver disease in Western countries and its worldwide prevalence continues to increase along with the growing obesity epidemic. Here, we show that a high-fat high-sucrose (HFHS) diet, eliciting chronic hepatosteatosis resembling human fatty liver, lowers hepatic nicotinamide adenine dinucleotide (NAD(+) ) levels driving reductions in hepatic mitochondrial content, function, and adenosine triphosphate (ATP) levels, in conjunction with robust increases in hepatic weight, lipid content, and peroxidation in C57BL/6J mice. To assess the effect of NAD(+) repletion on the development of steatosis in mice, nicotinamide riboside, a precursor of NAD(+) biosynthesis, was added to the HFHS diet, either as a preventive strategy or as a therapeutic intervention. We demonstrate that NR prevents and reverts NAFLD by inducing a sirtuin (SIRT)1- and SIRT3-dependent mitochondrial unfolded protein response, triggering an adaptive mitohormetic pathway to increase hepatic β-oxidation and mitochondrial complex content and activity. The cell-autonomous beneficial component of NR treatment was revealed in liver-specific Sirt1 knockout mice (Sirt1(hep-/-) ), whereas apolipoprotein E-deficient mice (Apoe(-/-) ) challenged with a high-fat high-cholesterol diet affirmed the use of NR in other independent models of NAFLD. Our data warrant the future evaluation of NAD(+) boosting strategies to manage the development or progression of NAFLD. © 2015 The Authors. Hepatology published by Wiley Periodicals, Inc., on behalf of the American Association for the Study of Liver Diseases.

  13. IDENTIFICATION OF NICOTINAMIDE MONONUCLEOTIDE DEAMIDASE OF THE BACTERIAL PYRIDINE NUCLEOTIDE CYCLE REVEALS A NOVEL BROADLY CONSERVED AMIDOHYDROLASE FAMILY

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Galeazzi, Luca; Bocci, Paolo; Amici, Adolfo

    2011-09-27

    The pyridine nucleotide cycle (PNC) is a network of salvage and recycling routes maintaining homeostasis of NAD(P) cofactor pool in the cell. Nicotinamide mononucleotide (NMN) deamidase (EC 3.5.1.42), one of the key enzymes of the bacterial PNC was originally described in Enterobacteria, but the corresponding gene eluded identification for over 30 years. A genomics-based reconstruction of NAD metabolism across hundreds bacterial species suggested that NMN deamidase reaction is the only possible way of nicotinamide salvage in the marine bacterium Shewanella oneidensis. This prediction was verified via purification of native NMN deamidase from S. oneidensis followed by the identification of themore » respective gene, termed pncC. Enzymatic characterization of the PncC protein, as well as phenotype analysis of deletion mutants, confirmed its proposed biochemical and physiological function in S. oneidensis. Of the three PncC homologs present in E. coli, NMN deamidase activity was confirmed only for the recombinant purified product of the ygaD gene. A comparative analysis at the level of sequence and three dimensional structure, which is available for one of the PncC family member, shows no homology with any previously described amidohydrolases. Multiple alignment analysis of functional and non functional PncC homologs, together with NMN docking experiments, allowed us to tentatively identify the active site area and conserved residues therein. An observed broad phylogenomic distribution of predicted functional PncCs in bacterial kingdom is consistent with a possible role in detoxification of NMN, resulting from NAD utilization by DNA ligase.« less

  14. Antitumor effect of combined NAMPT and CD73 inhibition in an ovarian cancer model.

    PubMed

    Sociali, Giovanna; Raffaghello, Lizzia; Magnone, Mirko; Zamporlini, Federica; Emionite, Laura; Sturla, Laura; Bianchi, Giovanna; Vigliarolo, Tiziana; Nahimana, Aimable; Nencioni, Alessio; Raffaelli, Nadia; Bruzzone, Santina

    2016-01-19

    Nicotinamide phosphoribosyltransferase (NAMPT) is a crucial enzyme in the biosynthesis of intracellular NAD+. NAMPT inhibitors have potent anticancer activity in several preclinical models by depleting NAD+ and ATP levels. Recently, we demonstrated that CD73 enables the utilization of extracellular NAD+/nicotinamide mononucleotide (NMN) by converting them to Nicotinamide riboside (NR), which can cross the plasmamembrane and fuel intracellular NAD+ biosynthesis in human cells. These processes are herein confirmed to also occur in a human ovarian carcinoma cell line (OVCAR-3), by means of CD73 or NRK1 specific silencing. Next, we investigated the anti-tumor activity of the simultaneous inhibition of NAMPT (with FK866) and CD73 (with α, β-methylene adenosine 5'-diphosphate, APCP), in an in vivo human ovarian carcinoma model. Interestingly, the combined therapy was found to significantly decrease intratumor NAD+, NMN and ATP levels, compared with single treatments. In addition, the concentration of these nucleotides in ascitic exudates was more remarkably reduced in animals treated with both FK866 and APCP compared with single treatments. Importantly, tumors treated with FK866 in combination with APCP contained a statistically significant lower proportion of Ki67 positive proliferating cells and a higher percentage of necrotic area. Finally, a slight but significant increase in animal survival in response to the combined therapy, compared to the single agents, could be demonstrated. Our results indicate that the pharmacological inhibition of CD73 enzymatic activity could be considered as a means to potentiate the anti-cancer effects of NAMPT inhibitors.

  15. Vibrio Phage KVP40 Encodes a Functional NAD+ Salvage Pathway.

    PubMed

    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 + for ADP-ribosylation of proteins involved in transcribing and translating the phage genome. We show here that phage KVP40 encodes a functional pyridine nucleotide scavenging pathway that is expressed during the metabolic period of the infection cycle. The pathway is conserved in other large, dsDNA phages in which the two genes, nadV and natV , share an evolutionary history in their respective phage-host group. Copyright © 2017 American Society for Microbiology.

  16. 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.

    PubMed

    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, relative activities toward Sia derivatives have been obtained. The preference of mouse CSS toward Neu5Ac and the ability of the rainbow trout enzyme to activate both KDN and Neu5Ac were confirmed. Thus, this simple and time-saving method is suitable for a systematic comparison of enzyme activity of structurally mutated enzymes based on the relative specific activity.

  17. Biochemical characterization of a new nicotinamidase from an unclassified bacterium thriving in a geothermal water stream microbial mat community

    PubMed Central

    Zapata-Pérez, Rubén; Martínez-Moñino, Ana-Belén; García-Saura, Antonio-Ginés; Cabanes, Juana; Takami, Hideto

    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. PMID:28750065

  18. Nicotinamide mononucleotide protects against pro-inflammatory cytokine-mediated impairment of mouse islet function.

    PubMed

    Caton, P W; Kieswich, J; Yaqoob, M M; Holness, M J; Sugden, M C

    2011-12-01

    Nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme for NAD(+) biosynthesis, exists as intracellular NAMPT (iNAMPT) and extracellular NAMPT (eNAMPT). eNAMPT, secreted from adipose tissue, promotes insulin secretion. Administration of nicotinamide mononucleotide (NMN), a product of the eNAMPT reaction, corrects impaired islet function in Nampt ( +/- ) mice. One of its potential targets is the NAD(+)-dependent deacetylase sirtuin 1. We hypothesised that altered NAMPT activity might contribute to the suppression of islet function associated with inflammation, and aimed to determine whether NMN could improve cytokine-mediated islet dysfunction. Acute effects of NMN on cytokine-mediated islet dysfunction were examined in islets incubated with TNFα and IL1β, and in mice fed a fructose-rich diet (FRD) for 16 weeks. Changes in iNAMPT, eNAMPT and inflammation levels were determined in FRD-fed mice. FRD-fed mice displayed markedly lower levels of circulating eNAMPT, with impaired insulin secretion and raised islet expression of Il1b. NMN administration lowered Il1b expression and restored suppressed insulin secretion in FRD-fed mice. NMN also restored insulin secretion in islets cultured with pro-inflammatory cytokines. The changes in islet function corresponded with changes in key markers of islet function and differentiation. The anti-inflammatory effects of NMN were partially blocked by inhibition of sirtuin 1. Chronic fructose feeding causes severe islet dysfunction in mice. Onset of beta cell failure in FRD-fed mice may occur via lowered secretion of eNAMPT, leading to increased islet inflammation and impaired beta cell function. Administration of exogenous NMN to FRD-fed mice corrects inflammation-induced islet dysfunction. Modulation of this pathway may be an attractive target for amelioration of islet dysfunction associated with inflammation.

  19. 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?

    PubMed

    Synesiou, Elena; Fairbanks, Lynnette D; Simmonds, H Anne; Slominska, Ewa M; Smolenski, Ryszard T; Carrey, Elizabeth A

    2011-06-01

    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, N(1)-methylnicotinamide and 4Py-riboside) and the major nicotinamide metabolite N(1)-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.

  20. Effects of Cavities at the Nicotinamide Binding Site of Liver Alcohol Dehydrogenase on Structure, Dynamics and Catalysis

    PubMed Central

    2015-01-01

    A role for protein dynamics in enzymatic catalysis of hydrogen transfer has received substantial scientific support, but the connections between protein structure and catalysis remain to be established. Valine residues 203 and 207 are at the binding site for the nicotinamide ring of the coenzyme in liver alcohol dehydrogenase and have been suggested to facilitate catalysis with “protein-promoting vibrations” (PPV). We find that the V207A substitution has small effects on steady-state kinetic constants and the rate of hydrogen transfer; the introduced cavity is empty and is tolerated with minimal effects on structure (determined at 1.2 Å for the complex with NAD+ and 2,3,4,5,6-pentafluorobenzyl alcohol). Thus, no evidence is found to support a role for Val-207 in the dynamics of catalysis. The protein structures and ligand geometries (including donor–acceptor distances) in the V203A enzyme complexed with NAD+ and 2,3,4,5,6-pentafluorobenzyl alcohol or 2,2,2-trifluoroethanol (determined at 1.1 Å) are very similar to those for the wild-type enzyme, except that the introduced cavity accommodates a new water molecule that contacts the nicotinamide ring. The structures of the V203A enzyme complexes suggest, in contrast to previous studies, that the diminished tunneling and decreased rate of hydride transfer (16-fold, relative to that of the wild-type enzyme) are not due to differences in ground-state ligand geometries. The V203A substitution may alter the PPV and the reorganization energy for hydrogen transfer, but the protein scaffold and equilibrium thermal motions within the Michaelis complex may be more significant for enzyme catalysis. PMID:24437493

  1. The sodium phosphate cotransporter family and nicotinamide phosphoribosyltransferase contribute to the daily oscillation of plasma inorganic phosphate concentration.

    PubMed

    Miyagawa, Atsumi; Tatsumi, Sawako; Takahama, Wako; Fujii, Osamu; Nagamoto, Kenta; Kinoshita, Emi; Nomura, Kengo; Ikuta, Kayo; Fujii, Toru; Hanazaki, Ai; Kaneko, Ichiro; Segawa, Hiroko; Miyamoto, Ken-Ichi

    2018-05-01

    Circulating inorganic phosphate exhibits a remarkable daily oscillation based on food intake. In humans and rodents, the daily oscillation in response to food intake may be coordinated to control the intestinal absorption, renal excretion, cellular shifts, and extracellular concentration of inorganic phosphate. However, mechanisms regulating the resulting oscillation are unknown. Here we investigated the roles of the sodium phosphate cotransporter SLC34 (Npt2) family and nicotinamide phosphoribosyltransferase (Nampt) in the daily oscillation of plasma inorganic phosphate levels. First, it is roughly linked to urinary inorganic phosphate excretion. Second, expression of renal Npt2a and Npt2c, and intestinal Npt2b proteins also exhibit a dynamic daily oscillation. Analyses of Npt2a, Npt2b, and Npt2c knockout mice revealed the importance of renal inorganic phosphate reabsorption and cellular inorganic phosphate shifts in the daily oscillation. Third, experiments in which nicotinamide and a specific Nampt inhibitor (FK866) were administered in the active and rest phases revealed that the Nampt/NAD + system is involved in renal inorganic phosphate excretion. Additionally, for cellular shifts, liver-specific Nampt deletion disturbed the daily oscillation of plasma phosphate during the rest but not the active phase. In systemic Nampt +/- mice, NAD levels were significantly reduced in the liver, kidney, and intestine, and the daily oscillation (active and rest phases) of the plasma phosphate concentration was attenuated. Thus, the Nampt/NAD + system for Npt2 regulation and cellular shifts to tissues such as the liver play an important role in generating daily oscillation of plasma inorganic phosphate levels. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  2. Biochemical characterization of a new nicotinamidase from an unclassified bacterium thriving in a geothermal water stream microbial mat community.

    PubMed

    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.

  3. Hypophosphatemia after Hepatectomy or Pancreatectomy: Role of the Nicotinamide Phosphoribosyltransferase.

    PubMed

    Zheng, Jian; Glezerman, Ilya G; Sadot, Eran; McNeil, Anjuli; Zarama, Cristina; Gönen, Mithat; Creasy, John; Pak, Linda M; Balachandran, Vinod P; D'Angelica, Michael I; Allen, Peter J; DeMatteo, Ronald P; Kingham, T Peter; Jarnagin, William R; Jaimes, Edgar A

    2017-10-01

    Postoperative hypophosphatemia is common and is associated with a lower risk of liver failure after hepatectomy, but higher morbidity after pancreatectomy. Whether different physiologic mechanisms underlie the hypophosphatemia associated with these very different clinical outcomes is unclear. This study aims to evaluate the underlying mechanism in postoperative hypophosphatemia. We prospectively enrolled 120 patients who underwent major hepatectomy (n = 30), minor hepatectomy (n = 30), pancreatectomy (n = 30), and laparotomy without resection (control group, n = 30). Preoperative and postoperative serum and urinary phosphorus, calcium, and creatinine, as well as phosphaturic factors, including serum nicotinamide phosphoribosyltransferase (NAMPT), fibroblast growth factor-23, and parathyroid hormone were measured. In addition, we evaluated urinary levels of nicotinamide catabolites, N-methyl-2-pyridone-5-carboxamide and N-methyl-4-pyridone-3-carboxamide. We found that significant hypophosphatemia occurred from postoperative day (POD) 1 to POD 2 in all 4 groups and was preceded by hyperphosphaturia from preoperative day to POD 1. Phosphate level alterations were associated with a significant increase in NAMPT levels from preoperative day to POD 2 in all 3 resected groups, but not in the control group. The fibroblast growth factor-23 levels were significantly decreased postoperatively in all 4 groups, and parathyroid hormone levels did not change in any of the 4 groups. Urine levels of N-methyl-2-pyridone-5-carboxamide and N-methyl-4-pyridone-3-carboxamide decreased significantly in all 4 groups postoperatively. This study demonstrates that the mechanism of hypophosphatemia is the same for both liver and pancreas resections. Postoperative hypophosphatemia is associated with increased NAMPT. The mechanism that upregulates NAMPT and its role on disparate clinical outcomes in postoperative patients warrant additional investigation. Copyright © 2017 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  4. Bone marrow niche-inspired, multi-phase expansion of megakaryocytic progenitors with high polyploidization potential

    PubMed Central

    Panuganti, Swapna; Papoutsakis, Eleftherios T.; Miller, William M.

    2010-01-01

    Background Megakaryopoiesis encompasses hematopoietic stem and progenitor cell (HSPC) commitment to the megakaryocytic cell (Mk) lineage, expansion of Mk progenitors and mature Mks, polyploidization, and platelet release. pH and pO2 increase from the endosteum to sinuses, and different cytokines are important for various stages of differentiation. We hypothesized that mimicking the changing conditions during Mk differentiation in the bone marrow would facilitate expansion of progenitors that could generate many high-ploidy Mks. Methods CD34+ HSPCs were cultured at pH 7.2 and 5% O2 with stem cell factor (SCF), thrombopoietin (Tpo), and all combinations of Interleukin (IL)-3, IL-6, IL-11, and Flt-3 ligand to promote Mk progenitor expansion. Cells cultured with selected cytokines were shifted to pH 7.4 and 20% O2 to generate mature Mks, and treated with nicotinamide to enhance polyploidization. Results Using Tpo+SCF+IL-3+IL-11, we obtained 3.5 CD34+CD41+ Mk progenitors per input HSPC, while increasing purity from 1% to 17%. Cytokine cocktails with IL-3 yielded more progenitors and mature Mks, although the purities were lower. Mk production was much greater at higher pH and pO2. Although fewer progenitors were present, shifting to 20% O2/pH 7.4 at day 5 (versus days 7 or 9) yielded the greatest mature Mk production, 14 per input HSPC. Nicotinamide more than doubled the percentage of high-ploidy Mks to 40%. Discussion We obtained extensive Mk progenitor expansion, while ensuring that the progenitors could produce high-ploidy Mks. We anticipate that subsequent optimization of cytokines for mature Mk production and delayed nicotinamide addition will greatly increase high-ploidy Mk production. PMID:20482285

  5. Umbilical cord blood expansion with nicotinamide provides long-term multilineage engraftment.

    PubMed

    Horwitz, Mitchell E; Chao, Nelson J; Rizzieri, David A; Long, Gwynn D; Sullivan, Keith M; Gasparetto, Cristina; Chute, John P; Morris, Ashley; McDonald, Carolyn; Waters-Pick, Barbara; Stiff, Patrick; Wease, Steven; Peled, Amnon; Snyder, David; Cohen, Einat Galamidi; Shoham, Hadas; Landau, Efrat; Friend, Etty; Peleg, Iddo; Aschengrau, Dorit; Yackoubov, Dima; Kurtzberg, Joanne; Peled, Tony

    2014-07-01

    Delayed hematopoietic recovery is a major drawback of umbilical cord blood (UCB) transplantation. Transplantation of ex vivo-expanded UCB shortens time to hematopoietic recovery, but long-term, robust engraftment by the expanded unit has yet to be demonstrated. We tested the hypothesis that a UCB-derived cell product consisting of stem cells expanded for 21 days in the presence of nicotinamide and a noncultured T cell fraction (NiCord) can accelerate hematopoietic recovery and provide long-term engraftment. In a phase I trial, 11 adults with hematologic malignancies received myeloablative bone marrow conditioning followed by transplantation with NiCord and a second unmanipulated UCB unit. Safety, hematopoietic recovery, and donor engraftment were assessed and compared with historical controls. No adverse events were attributable to the infusion of NiCord. Complete or partial neutrophil and T cell engraftment derived from NiCord was observed in 8 patients, and NiCord engraftment remained stable in all patients, with a median follow-up of 21 months. Two patients achieved long-term engraftment with the unmanipulated unit. Patients transplanted with NiCord achieved earlier median neutrophil recovery (13 vs. 25 days, P < 0.001) compared with that seen in historical controls. The 1-year overall and progression-free survival rates were 82% and 73%, respectively. UCB-derived hematopoietic stem and progenitor cells expanded in the presence of nicotinamide and transplanted with a T cell-containing fraction contain both short-term and long-term repopulating cells. The results justify further study of NiCord transplantation as a single UCB graft. If long-term safety is confirmed, NiCord has the potential to broaden accessibility and reduce the toxicity of UCB transplantation. Clinicaltrials.gov NCT01221857. Gamida Cell Ltd.

  6. Hepatic NAD+ deficiency as a therapeutic target for non‐alcoholic fatty liver disease in ageing

    PubMed Central

    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

  7. Synthesis and evaluation of novel radioiodinated nicotinamides for malignant melanoma.

    PubMed

    Liu, Xiang; Pham, Tien Q; Berghofer, Paula; Chapman, Janette; Greguric, Ivan; Mitchell, Peter; Mattner, Filomena; Loc'h, Christian; Katsifis, Andrew

    2008-10-01

    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. [(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. The iodonicotinamides displayed low-affinity binding for sigma(1)-sigma(2) receptors (K(i)>300 nM). In biodistribution studies in mice, N-(2-(diethylamino)ethyl)-5-[(123)I]iodonicotinamide ([(123)I]1) exhibited the fastest and highest uptake of the nicotinamide series in the B16F0 tumour at 1 h ( approximately 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 [(123)I]1, while the gastrointestinal tract amounted to 17% ID. Haloperidol was unable to reduce the uptake of [(123)I]1 in pigmented mice, indicating that this uptake was likely due to an interaction with melanin. SPECT imaging of [(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. These findings suggest that [(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.

  8. 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.

    PubMed

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

    2016-11-10

    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.

  9. 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

    PubMed Central

    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

  10. Curcumin and resveratrol rescue cortical-hippocampal system from chronic fluoride-induced neurodegeneration and enhance memory retrieval.

    PubMed

    Sharma, Chhavi; Suhalka, Pooja; Bhatnagar, Maheep

    2018-04-13

    The aim of this study was: (1) to evaluate the neuroprotective effect of resveratrol and curcumin on nicotinamide adenine dinucleotide phosphate diaphorase activity in neuronal cell in subregions of mice brain, (2) to evaluate the effects on antioxidant status and (3) to evaluate the protective effects of phytochemicals on learning and memory following fluoride exposure. Young mice (one month old, body weight (BW) 30 ± 5 mg) were provided with 120 ppm sodium fluoride dissolved in drinking water. They were given curcumin (30 mg/kg BW) or resveratrol (30 mg/kg BW) orally once in a day up to 30 days. Effects of resveratrol and curcumin on spatial learning and memory were studied using Morris water maze and classic maze test. Effects on brain antioxidants' (lactose dehydrogenase (LDH), malondialdehyde and reactive oxygen species) status were also studied in vitro. Histochemistry was done to assess the effect of treatments on nitric oxide neurotransmitter. Our study showed that in fluoride-treated animals, the number of nicotinamide adenine dinucleotide phosphate diaphorase positive neurons, intracellular Ca 2+ , reactive oxygen species level, LDH and malondialdehyde concentration increased significantly. Interestingly, after treatment with curcumin or resveratrol, a significant decrease in the number of nicotinamide adenine dinucleotide phosphate diaphorase positive neurons and antioxidant status was observed. This decrease was more considerable in resveratrol-treated group. Our study indicates that both antioxidants, curcumin and resveratrol, are useful in reducing neurodegeneration in selective areas of cornus ammonis 1 (CA1), CA3, dentate gyrus (DG) and the cortex of mice brain and in recuperating the loss of memory and learning caused due to fluoride exposure.

  11. Administration of nicotinamide riboside prevents oxidative stress and organ injury in sepsis.

    PubMed

    Hong, Guangliang; Zheng, Dong; Zhang, Lulu; Ni, Rui; Wang, Grace; Fan, Guo-Chang; Lu, Zhongqiu; Peng, Tianqing

    2018-08-01

    Sepsis-caused multiple organ failure remains the major cause of morbidity and mortality in intensive care units. Nicotinamide riboside (NR) is a precursor of nicotinamide adenine dinucleotide (NAD + ), which is important in regulating oxidative stress. This study investigated whether administration of NR prevented oxidative stress and organ injury in sepsis. Mouse sepsis models were induced by injection of lipopolysaccharides (LPS) or feces-injection-in-peritoneum. NR was given before sepsis onset. Cultured macrophages and endothelial cells were incubated with various agents. Administration of NR elevated the NAD + levels, and elicited a reduction of oxidative stress, inflammation and caspase-3 activity in lung and heart tissues, which correlated with attenuation of pulmonary microvascular permeability and myocardial dysfunction, leading to less mortality in sepsis models. These protective effects of NR were associated with decreased levels of plasma high mobility group box-1 (HMGB1) in septic mice. Consistently, pre-treatment of macrophages with NR increased NAD + content and reduced HMGB1 release upon LPS stimulation. NR also prevented reactive oxygen species (ROS) production and apoptosis in endothelial cells induced by a conditioned-medium collected from LPS-treated macrophages. Furthermore, inhibition of SIRT1 by EX527 offset the negative effects of NR on HMGB1 release in macrophages, and ROS and apoptosis in endothelial cells. Administration of NR prevents lung and heart injury, and improves the survival in sepsis, likely by inhibiting HMGB1 release and oxidative stress via the NAD + /SIRT1 signaling. Given NR has been used as a health supplement, it may be a useful agent to prevent organ injury in sepsis. Copyright © 2018 Elsevier Inc. All rights reserved.

  12. Nicotinamide riboside, a form of vitamin B3 and NAD+ precursor, relieves the nociceptive and aversive dimensions of paclitaxel-induced peripheral neuropathy in female rats.

    PubMed

    Hamity, Marta V; White, Stephanie R; Walder, Roxanne Y; Schmidt, Mark S; Brenner, Charles; Hammond, Donna L

    2017-05-01

    Injury to sensory afferents may contribute to the peripheral neuropathies that develop after administration of chemotherapeutic agents. Manipulations that increase levels of nicotinamide adenine dinucleotide (NAD) can protect against neuronal injury. This study examined whether nicotinamide riboside (NR), a third form of vitamin B3 and precursor of NAD, diminishes tactile hypersensitivity and place escape-avoidance behaviors in a rodent model of paclitaxel-induced peripheral neuropathy. Female Sprague-Dawley rats received 3 intravenous injections of 6.6 mg/kg paclitaxel over 5 days. Daily oral administration of 200 mg/kg NR beginning 7 days before paclitaxel treatment and continuing for another 24 days prevented the development of tactile hypersensitivity and blunted place escape-avoidance behaviors. These effects were sustained after a 2-week washout period. This dose of NR increased blood levels of NAD by 50%, did not interfere with the myelosuppressive effects of paclitaxel, and did not produce adverse locomotor effects. Treatment with 200 mg/kg NR for 3 weeks after paclitaxel reversed the well-established tactile hypersensitivity in a subset of rats and blunted escape-avoidance behaviors. Pretreatment with 100 mg/kg oral acetyl-L-carnitine (ALCAR) did not prevent paclitaxel-induced tactile hypersensitivity or blunt escape-avoidance behaviors. ALCAR by itself produced tactile hypersensitivity. These findings suggest that agents that increase NAD, a critical cofactor for mitochondrial oxidative phosphorylation systems and cellular redox systems involved with fuel utilization and energy metabolism, represent a novel therapeutic approach for relief of chemotherapy-induced peripheral neuropathies. Because NR is a vitamin B3 precursor of NAD and a nutritional supplement, clinical tests of this hypothesis may be accelerated.

  13. Thermodynamic and NMR analyses of NADPH binding to lipocalin-type prostaglandin D synthase

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Qin, Shubin; Shimamoto, Shigeru; Maruno, Takahiro

    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 formore » 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.« less

  14. Protective effect of dietary potassium against vascular injury in salt-sensitive hypertension.

    PubMed

    Kido, Makiko; Ando, Katsuyuki; Onozato, Maristela L; Tojo, Akihiro; Yoshikawa, Masahiro; Ogita, Teruhiko; Fujita, Toshiro

    2008-02-01

    Hypertensive cardiovascular damage is accelerated by salt loading but counteracted by dietary potassium supplementation. We suggested recently that antioxidant actions of potassium contribute to protection against salt-induced cardiac dysfunction. Therefore, we examined whether potassium supplementation ameliorated cuff-induced vascular injury in salt-sensitive hypertension via suppression of oxidative stress. Four-week-old Dahl salt-sensitive rats were fed a normal-salt (0.3% NaCl), high-salt (8% NaCl), or high-salt plus high-potassium (8% KCl) diet for 5 weeks, and some of the rats fed a high-salt diet were also given antioxidants. One week after the start of the treatments, a silicone cuff was implanted around the femoral artery. Examination revealed increased cuff-induced neointimal proliferation with adventitial macrophage infiltration in arteries from salt-loaded Dahl salt-sensitive rats compared with that in arteries from non-salt-loaded animals (intima/media ratio: 0.471+/-0.070 versus 0.302+/-0.037; P<0.05), associated with regional superoxide overproduction and reduced nicotinamide-adenine dinucleotide phosphate oxidase activation and mRNA overexpression. On the other hand, simultaneous potassium supplementation attenuated salt-induced neointimal hyperplasia (intima/media ratio: 0.205+/-0.012; P<0.001), adventitial macrophage infiltration, superoxide overproduction, and reduced nicotinamide-adenine dinucleotide phosphate oxidase activation and overexpression. Antioxidants, which decrease vascular oxidative stress, also reduced neointima formation induced by salt excess. In conclusion, high-potassium diets seems to have a protective effect against the development of vascular damage induced by salt loading mediated, at least in part, through suppression of the production of reactive oxygen species probably generated by reduced nicotinamide-adenine dinucleotide phosphate oxidase.

  15. Association of circulating levels of nicotinamide phosphoribosyltransferase (NAMPT/Visfatin) and of a frequent polymorphism in the promoter of the NAMPT gene with coronary artery disease in diabetic and non-diabetic subjects

    PubMed Central

    2013-01-01

    Background Nicotinamide phosphoribosyltransferase (NAMPT) is the limiting enzyme in one of pathways of synthesis of Nicotinamide Adenine Dinucleotide, a redox coenzyme. NAMPT is considered as an insulin-mimetic factor and a potential regulatory factor in inflammatory and immune processes. Associations of circulating NAMPT levels with cardiovascular disease (CVD) and insulin resistance have been reported. We investigated association of circulating NAMPT levels and the rs9770242 NAMPT gene polymorphism with coronary artery disease (CAD). Methods We studied 594 Brazilian subjects undergoing a coronary angiography (49% of whom had type 2 diabetes). CAD, defined as stenosis greater than 50% in one major coronary vessel or branch, was observed in 68% of subjects. Genetic studies were also performed in 858 North-American Non-Hispanic White subjects with type 2 diabetes (49% with CAD). Results We observed an interaction between glycemic and CAD status on the comparison of NAMPT levels by CAD status. NAMPT levels were higher in type 2 diabetic patients with CAD as compared to those without CAD: 5.27 ± 2.93 ng/ml vs. 4.43 ± 2.94 ng/ml, p = 0.006 (mean ± SD). NAMPT levels were not significantly different in non-diabetic subjects with or without CAD. The T-allele of rs9770242 was associated with CAD in the Brazilian cohort (OR 1.46, 95% CI 1.06 - 2.01, p = 0.02) while no association was observed in the North-American cohort. Conclusions Our data suggest that circulating NAMPT levels are associated with CAD in type 2 diabetic patients. NAMPT rs9770242 polymorphism may be associated with CAD in some populations. PMID:23968400

  16. NAMPT/PBEF1 enzymatic activity is indispensable for myeloma cell growth and osteoclast activity

    PubMed Central

    Venkateshaiah, Sathisha Upparahalli; Khan, Sharmin; Ling, Wen; Bam, Rakesh; Li, Xin; van Rhee, Frits; Usmani, Saad; Barlogie, Bart; Epstein, Joshua; Yaccoby, Shmuel

    2015-01-01

    Multiple myeloma (MM) cells typically grow in focal lesions, stimulating osteoclasts that destroy bone and support MM. Osteoclasts and MM cells are hypermetabolic. The coenzyme nicotinamide adenine dinucleotide (NAD+) is not only essential for cellular metabolism; it also affects activity of NAD-dependent enzymes, such as PARP-1 and SIRT-1. Nicotinamide phos-phoribosyltransferase (NAMPT/PBEF/visfatin, encoded by PBEF1) is a rate-limiting enzyme in NAD+ biosynthesis from nicotinamide. Coculture of primary MM cells with osteoclasts induced PBEF1 upregulation in both cell types. PBEF1 expression was higher in experimental myelomatous bones than in nonmyelomatous bone and higher in MM patients’ plasma cells than in healthy donors’ counterparts. APO866 is a specific PBEF1 inhibitor known to deplete cellular NAD+, APO866 at low nanomolar concentrations inhibited growth of primary MM cells or MM cell lines cultured alone or cocultured with osteoclasts and induced apoptosis in these cells. PBEF1 activity and NAD+ content were reduced in MM cells by APO866, resulting in lower activity of PARP-1 and SIRT-1. The inhibitory effect of APO866 on MM cell growth was abrogated by supplementation of extracellular NAD+ or NAM. APO866 inhibited NF-κB activity in osteoclast precursors and suppressed osteoclast formation and activity. PBEF1 knockdown similarly inhibited MM cell growth and osteoclast formation. In the SCID-rab model, APO866 inhibited growth of primary MM and H929 cells and prevented bone disease. These findings indicate that MM cells and osteoclasts are highly sensitive to NAD+ depletion and that PBEF1 inhibition represents a novel approach to target cellular metabolism and inhibit PARP-1 and bone disease in MM. PMID:23435312

  17. 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

    PubMed Central

    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. Methods: 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. Results: Body weight, serum luteinizing hormone (LH), follicle stimulating hormone (FSH), and testosterone levels, and sperm count (P < 0.05) and viability (P < 0.01) decreased in diabetic mice. Administration of glibenclamide significantly improved these reductions in diabetic animals (P < 0.05). However, the hydro alcoholic extract (300 mg/kg) enhanced sperm viability only in diabetic mice (P < 0.01). In addition, this dose of extract increased sperm count, LH, FSH, and testosterone in nondiabetic animals compared with the control group (P < 0.05). Conclusion: The results indicate that applied burdock root extract has anti-infertility effects in nondiabetic mice. Hence, this part of the A. lappa plant has an effect on the health of the reproductive system in order to improve diabetic conditions. PMID:26023292

  18. 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.

    PubMed

    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 < 0.05) and viability (P < 0.01) decreased in diabetic mice. Administration of glibenclamide significantly improved these reductions in diabetic animals (P < 0.05). However, the hydro alcoholic extract (300 mg/kg) enhanced sperm viability only in diabetic mice (P < 0.01). In addition, this dose of extract increased sperm count, LH, FSH, and testosterone in nondiabetic animals compared with the control group (P < 0.05). The results indicate that applied burdock root extract has anti-infertility effects in nondiabetic mice. Hence, this part of the A. lappa plant has an effect on the health of the reproductive system in order to improve diabetic conditions.

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

    PubMed

    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.

  20. Better than Nature: Nicotinamide Biomimetics That Outperform Natural Coenzymes

    PubMed Central

    2016-01-01

    The search for affordable, green biocatalytic processes is a challenge for chemicals manufacture. Redox biotransformations are potentially attractive, but they rely on unstable and expensive nicotinamide coenzymes that have prevented their widespread exploitation. Stoichiometric use of natural coenzymes is not viable economically, and the instability of these molecules hinders catalytic processes that employ coenzyme recycling. Here, we investigate the efficiency of man-made synthetic biomimetics of the natural coenzymes NAD(P)H in redox biocatalysis. Extensive studies with a range of oxidoreductases belonging to the “ene” reductase family show that these biomimetics are excellent analogues of the natural coenzymes, revealed also in crystal structures of the ene reductase XenA with selected biomimetics. In selected cases, these biomimetics outperform the natural coenzymes. “Better-than-Nature” biomimetics should find widespread application in fine and specialty chemicals production by harnessing the power of high stereo-, regio-, and chemoselective redox biocatalysts and enabling reactions under mild conditions at low cost. PMID:26727612

  1. Improved Ethanol Production from Xylose by Candida shehatae Induced by Dielectric Barrier Discharge Air Plasma

    NASA Astrophysics Data System (ADS)

    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.

  2. Injection order effects on efficacy of calcium chloride and sodium tripolyphosphate in controlling the pink color defect in uncured, intact turkey breast.

    PubMed

    Claus, James R; Sawyer, Christopher A; Vogel, Kurt D

    2010-04-01

    An experiment was conducted to test sequential injection of sodium tripolyphosphate (STP; 0.5% meat weight basis, mwb) followed by injection with or without addition of calcium chloride (CaCl(2), 500 ppm mwb), and to test the effect of post-injection delay prior to cooking. A second experiment evaluated the impact of injection order and delay time between independent addition of CaCl(2) (500 ppm mwb) and STP (0.5% mwb). Turkey was formulated without an added pink generating ligand (NONE), with nicotinamide (NIC; 0.1% mwb), or with sodium nitrite (NIT; 10 ppm mwb). A white colloid was observed in the extracellular space of treatments containing both STP and CaCl(2.) Addition of CaCl(2) decreased nitrosylhemochrome but did not reduce levels of nicotinamide hemochrome or CIE a(*) values. Injection order or delay between injections did not contribute to controlling the pink defect in cooked, intact turkey breast. Published by Elsevier Ltd.

  3. Effects of B Vitamins Overload on Plasma Insulin Level and Hydrogen Peroxide Generation in Rats.

    PubMed

    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.

  4. Terahertz spectroscopy and computational investigation of the flufenamic acid/nicotinamide cocrystal.

    PubMed

    Delaney, Sean P; Korter, Timothy M

    2015-04-02

    Terahertz spectroscopy probes the low-frequency vibrations that are sensitive to both the intermolecular and intramolecular interactions of molecules in the solid state. Thus, terahertz spectroscopy can be a useful tool in the investigation of crystalline pharmaceutical compounds, where slight changes in the packing arrangement can modify the overall effectiveness of a drug formulation. This is especially true for cases of polymorphic systems, hydrates/solvates, and cocrystals. In this work, the cocrystal of flufenamic acid with nicotinamide was investigated using terahertz spectroscopy and solid-state density functional theory. The solid-state simulations enable understanding of the low-frequency vibrations seen in the terahertz spectra, while also providing insight into the energetics involved in the formation of the cocrystal. The comparison of the cocrystal to the pure forms of the molecular components reveals that the cocrystal has better overall binding energy, driven by increased intermolecular hydrogen bond strength and greater London dispersion forces and that the trifluoromethyl torsional potential is significantly different between the studied solids.

  5. Baicalein-nicotinamide cocrystal with enhanced solubility, dissolution, and oral bioavailability.

    PubMed

    Huang, Yanting; Zhang, Bowen; Gao, Yuan; Zhang, Jianjun; Shi, Limin

    2014-08-01

    The purpose of this study was to investigate the effect of preparation methods on cocrystallization between baicalein (BE) and nicotinamide (NCT), their intermolecular interaction, and to demonstrate that BE-NCT cocrystal can achieve the simultaneous enhancement in solubility, dissolution, and oral bioavailability of BE. The cocrystals from three preparation methods have the similar differential scanning calorimetry thermograms and X-ray powder diffraction patterns. Compared with crystalline BE, BE-NCT cocrystal has significantly improved the solubility and dissolution of BE. In addition, the cocrystal exhibits a 2.49-fold higher peak plasma concentration (Cmax) and 2.80-fold higher area under the curve (AUC) in rats. This prominent improvement in oral bioavailability is even greater than the previously reported BE nanocrystal. This investigation enriched the present understanding of cocrystals on their behavior in vitro and in vivo, and built the groundwork for future development of BE as a promising compound into efficacious drug products. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  6. A General Tool for Engineering the NAD/NADP Cofactor Preference of Oxidoreductases.

    PubMed

    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).

  7. The SARM1 Toll/Interleukin-1 Receptor Domain Possesses Intrinsic NAD+ Cleavage Activity that Promotes Pathological Axonal Degeneration.

    PubMed

    Essuman, Kow; Summers, Daniel W; Sasaki, Yo; Mao, Xianrong; DiAntonio, Aaron; Milbrandt, Jeffrey

    2017-03-22

    Axonal degeneration is an early and prominent feature of many neurological disorders. SARM1 is the central executioner of the axonal degeneration pathway that culminates in depletion of axonal NAD + , yet the identity of the underlying NAD + -depleting enzyme(s) is unknown. Here, in a series of experiments using purified proteins from mammalian cells, bacteria, and a cell-free protein translation system, we show that the SARM1-TIR domain itself has intrinsic NADase activity-cleaving NAD + into ADP-ribose (ADPR), cyclic ADPR, and nicotinamide, with nicotinamide serving as a feedback inhibitor of the enzyme. Using traumatic and vincristine-induced injury models in neurons, we demonstrate that the NADase activity of full-length SARM1 is required in axons to promote axonal NAD + depletion and axonal degeneration after injury. Hence, the SARM1 enzyme represents a novel therapeutic target for axonopathies. Moreover, the widely utilized TIR domain is a protein motif that can possess enzymatic activity. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Emissive Synthetic Cofactors: An Isomorphic, Isofunctional, and Responsive NAD+ Analogue.

    PubMed

    Rovira, Alexander R; Fin, Andrea; Tor, Yitzhak

    2017-11-08

    The synthesis, photophysics, and biochemical utility of a fluorescent NAD + analogue based on an isothiazolo[4,3-d]pyrimidine core (N tz AD + ) are described. Enzymatic reactions, photophysically monitored in real time, show N tz AD + and N tz ADH to be substrates for yeast alcohol dehydrogenase and lactate dehydrogenase, respectively, with reaction rates comparable to that of the native cofactors. A drop in fluorescence is seen as N tz AD + is converted to N tz ADH, reflecting a complementary photophysical behavior to that of the native NAD + /NADH. N tz AD + and N tz ADH serve as substrates for NADase, which selectively cleaves the nicotinamide's glycosidic bond yielding tz ADP-ribose. N tz AD + also serves as a substrate for ribosyl transferases, including human adenosine ribosyl transferase 5 (ART5) and Cholera toxin subunit A (CTA), which hydrolyze the nicotinamide and transfer tz ADP-ribose to an arginine analogue, respectively. These reactions can be monitored by fluorescence spectroscopy, in stark contrast to the corresponding processes with the nonemissive NAD + .

  9. NAMPT and NAMPT-controlled NAD Metabolism in Vascular Repair.

    PubMed

    Wang, Pei; Li, Wen-Lin; Liu, Jian-Min; Miao, Chao-Yu

    2016-06-01

    Vascular repair plays important roles in postischemic remodeling and rehabilitation in cardiovascular and cerebrovascular disease, such as stroke and myocardial infarction. Nicotinamide adenine dinucleotide (NAD), a well-known coenzyme involved in electron transport chain for generation of adenosine triphosphate, has emerged as an important controller regulating various biological signaling pathways. Nicotinamide phosphoribosyltransferase (NAMPT) is the rate-limiting enzyme for NAD biosynthesis in mammals. NAMPT may also act in a nonenzymatic manner, presumably mediated by unknown receptor(s). Rapidly accumulating data in the past decade show that NAMPT and NAMPT-controlled NAD metabolism regulate fundamental biological functions in endothelial cells, vascular smooth muscle cells, and endothelial progenitor cells. The NAD-consuming proteins, including sirtuins, poly-ADP-ribose polymerases (PARPs), and CD38, may contribute to the regulatory effects of NAMPT-NAD axis in these cells and vascular repair. This review discusses the current data regarding NAMPT and NAMPT-controlled NAD metabolism in vascular repair and the clinical potential translational application of NAMPT-related products in treatment of cardiovascular and cerebrovascular disease.

  10. Transcriptional regulation of nicotinamide adenine dinucleotide phosphate: quinone oxidoreductase in murine hepatoma cells by 6-(methylsufinyl)hexyl isothiocyanate, an active principle of wasabi (Eutrema wasabi Maxim).

    PubMed

    Hou, D X; Fukuda, M; Fujii, M; Fuke, Y

    2000-12-20

    Wasabi is a very popular pungent spice in Japan. This study examined the ability of 6-(methylsufinyl)hexyl isothiocyanate (6-MITC), an active principle of wasabi, to induce the cellular expression of nicotinamide adenine dinucleotide phosphate: quinone oxidoreductase (QR) in Hepa 1c1c7 cells. The cells were treated with various concentrations of 6-MITC, and were then assessed for cell growth, QR activity and QR mRNA expression. The induction of QR activity and QR mRNA expression was time- and dose-responsive over a narrow range of 0.1-5 microM, with declining induction at higher concentrations due to cell toxicity. Furthermore, transfection studies demonstrated that the induction of transcription of the QR gene by 6-MITC involved an antioxidant/electrophile-responsive element (ARE/EpRE) activation. Our results suggest a novel mechanism by which dietary wasabi 6-MITC may be implicated in cancer chemoprevention.

  11. Synthesis of β-Nicotinamide Riboside Using an Efficient Two-Step Methodology.

    PubMed

    Zhang, Ning; Sauve, Anthony A

    2017-12-24

    A two-step chemical method for the synthesis of β-nicotinamide riboside (NR) is described. NR has achieved wide use as an NAD + precursor (vitamin B3) and can significantly increase central metabolite NAD + concentrations in mammalian cells. β-NR can be prepared with an efficient two-step procedure. The synthesis is initiated via coupling of commercially available 1,2,3,5-tetra-O-acetyl-β-D-ribofuranose with ethyl nicotinate in the presence of trimethylsilyl trifluoromethanesulfonate (TMSOTf). 1 H NMR showed that the product was formed with complete stereoselectivity to produce only the β-isomer in high yield (>90% versus starting sugar). The clean stereochemical result suggests that the coupling proceeds via a cationic cis-1,2-acyloxonium-sugar intermediate, which controls addition by nucleophiles to generate predominantly β-stereochemistry. The subsequent deprotection of esters in methanolic ammonia generates the desired product in 85% overall yield versus sugar. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

  12. The NAD+ precursor nicotinamide riboside enhances oxidative metabolism and protects against high-fat diet induced obesity

    PubMed Central

    Cantó, Carles; Houtkooper, Riekelt H.; Pirinen, Eija; Youn, Dou Y.; Oosterveer, Maaike H.; Cen, Yana; Fernandez-Marcos, Pablo J.; Yamamoto, Hiroyasu; Andreux, Pénélope A.; Cettour-Rose, Philippe; Gademann, Karl; Rinsch, Chris; Schoonjans, Kristina; Sauve, Anthony A.; Auwerx, Johan

    2013-01-01

    SUMMARY As NAD+ is a rate-limiting co-substrate for the sirtuin enzymes, its modulation is emerging as a valuable tool to regulate sirtuin function and, consequently, oxidative metabolism. In line with this premise, decreased activity of PARP-1 or CD38 —both NAD+ consumers— increases NAD+ bioavailability, resulting in SIRT1 activation and protection against metabolic disease. Here we evaluated whether similar effects could be achieved by increasing the supply of nicotinamide riboside (NR), a recently described natural NAD+ precursor with the ability to increase NAD+ levels, Sir2-dependent gene silencing and replicative lifespan in yeast. We show that NR supplementation in mammalian cells and mouse tissues increases NAD+ levels and activates SIRT1 and SIRT3, culminating in enhanced oxidative metabolism and protection against high fat diet-induced metabolic abnormalities. Consequently, our results indicate that the natural vitamin, NR, could be used as a nutritional supplement to ameliorate metabolic and age-related disorders characterized by defective mitochondrial function. PMID:22682224

  13. Effective treatment of mitochondrial myopathy by nicotinamide riboside, a vitamin B3

    PubMed Central

    Khan, Nahid A; Auranen, Mari; Paetau, Ilse; Pirinen, Eija; Euro, Liliya; Forsström, Saara; Pasila, Lotta; Velagapudi, Vidya; Carroll, Christopher J; Auwerx, Johan; Suomalainen, Anu

    2014-01-01

    Nutrient availability is the major regulator of life and reproduction, and a complex cellular signaling network has evolved to adapt organisms to fasting. These sensor pathways monitor cellular energy metabolism, especially mitochondrial ATP production and NAD+/NADH ratio, as major signals for nutritional state. We hypothesized that these signals would be modified by mitochondrial respiratory chain disease, because of inefficient NADH utilization and ATP production. Oral administration of nicotinamide riboside (NR), a vitamin B3 and NAD+ precursor, was previously shown to boost NAD+ levels in mice and to induce mitochondrial biogenesis. Here, we treated mitochondrial myopathy mice with NR. This vitamin effectively delayed early- and late-stage disease progression, by robustly inducing mitochondrial biogenesis in skeletal muscle and brown adipose tissue, preventing mitochondrial ultrastructure abnormalities and mtDNA deletion formation. NR further stimulated mitochondrial unfolded protein response, suggesting its protective role in mitochondrial disease. These results indicate that NR and strategies boosting NAD+ levels are a promising treatment strategy for mitochondrial myopathy. PMID:24711540

  14. Kynurenine Pathway Metabolism is Involved in the Maintenance of the Intracellular NAD+ Concentration in Human Primary Astrocytes

    PubMed Central

    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

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

    PubMed

    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.

  16. Flow-injection analysis with electrochemical detection of reduced nicotinamide adenine dinucleotide using 2,6-dichloroindophenol as a redox coupling agent.

    PubMed

    Tang, H T; Hajizadeh, K; Halsall, H B; Heineman, W R

    1991-01-01

    The determination of reduced nicotinamide adenine dinucleotide (NADH) by electrochemical oxidation requires a more positive potential than is predicted by the formal reduction potential for the NAD+/NADH couple. This problem is alleviated by use of 2,6-dichloroindophenol (DCIP) as a redox coupling agent for NADH. The electrochemical characteristics of DCIP at the glassy carbon electrode are examined by cyclic voltammetry and hydrodynamic voltammetry. NADH is determined by reaction with DCIP to form NAD+ and DCIPH2. DCIPH2 is then quantitated by flow-injection analysis with electrochemical detection by oxidation at a detector potential of +0.25 V at pH 7. NADH is determined over a linear range of 0.5 to 200 microM and with a detection limit of 0.38 microM. The lower detection potential for DCIPH2 compared to NADH helps to minimize interference from oxidizable components in serum samples.

  17. Isotope effect studies of the chemical mechanism of nicotinamide adenine dinucleotide malic enzyme from Crassula

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Grissom, C.B.; Willeford, O.; Wedding, R.T.

    1987-05-05

    The /sup 13/C primary kinetic isotope effect on the decarboxylation of malate by nicotinamide adenine dinucleotide malic enzyme from Crassula argentea is 1.0199 +/- 0.0006 with proteo L-malate-2-H and 1.0162 +/- 0.0003 with malate-2-d. The primary deuterium isotope effect is 1.45 +/- 0.10 on V/K and 1.93 +/- 0.13 on V/sub max/. This indicates a stepwise conversion of malate to pyruvate and CO/sub 2/ with hydride transfer preceding decarboxylation, thereby suggesting a discrete oxaloacetate intermediate. This is in agreement with the stepwise nature of the chemical mechanism of other malic enzymes despite the Crassula enzyme's inability to reduce or decarboxylatemore » oxaloacetate. Differences in morphology and allosteric regulation between enzymes suggest specialization of the Crassula malic enzyme for the physiology of crassulacean and acid metabolism while maintaining the catalytic events founds in malic enzymes from animal sources.« less

  18. Structural Basis for NADH/NAD+ Redox Sensing by a Rex Family Repressor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McLaughlin, K.J.; Soares, A.; Strain-Damerell, C. M.

    2010-05-28

    Nicotinamide adenine dinucleotides have emerged as key signals of the cellular redox state. Yet the structural basis for allosteric gene regulation by the ratio of reduced NADH to oxidized NAD{sup +} is poorly understood. A key sensor among Gram-positive bacteria, Rex represses alternative respiratory gene expression until a limited oxygen supply elevates the intracellular NADH:NAD{sup +} ratio. Here we investigate the molecular mechanism for NADH/NAD{sup +} sensing among Rex family members by determining structures of Thermus aquaticus Rex bound to (1) NAD{sup +}, (2) DNA operator, and (3) without ligand. Comparison with the Rex/NADH complex reveals that NADH releases Rexmore » from the DNA site following a 40{sup o} closure between the dimeric subunits. Complementary site-directed mutagenesis experiments implicate highly conserved residues in NAD-responsive DNA-binding activity. These rare views of a redox sensor in action establish a means for slight differences in the nicotinamide charge, pucker, and orientation to signal the redox state of the cell.« less

  19. Stereoselective synthesis of nicotinamide beta-riboside and nucleoside analogs.

    PubMed

    Franchetti, Palmarisa; Pasqualini, Michela; Petrelli, Riccardo; Ricciutelli, Massimo; Vita, Patrizia; Cappellacci, Loredana

    2004-09-20

    The beta-anomers of N-ribofuranosylnicotine-3-carboxamide (beta-NAR) and its nicotinic acid analog (beta-NaR) were obtained by stereoselective synthesis via glycosylation of the presilylated bases under Vorbruggen's protocol. A NAR analog, methylated in position 3 of the ribosylic moiety, is also reported.

  20. NAMPT is essential for the G-CSF-induced myeloid differentiation via a NAD+-sirtuin-1-dependent pathway

    USDA-ARS?s Scientific Manuscript database

    We identified nicotinamide phosphoribosyltransferase (NAMPT), also known as pre-B cell colony enhancing factor (PBEF), as an essential enzyme mediating granulocyte colony-stimulating factor (G-CSF)-triggered granulopoiesis in healthy individuals and in individuals with severe congenital neutropenia....

  1. Hyperthermophilic Archaeon Thermococcus kodakarensis Utilizes a Four-Step Pathway for NAD+ Salvage through Nicotinamide Deamination.

    PubMed

    Hachisuka, Shin-Ichi; Sato, Takaaki; Atomi, Haruyuki

    2018-06-01

    Many organisms possess pathways that regenerate NAD + from its degradation products, and two pathways are known to salvage NAD + from nicotinamide (Nm). One is a four-step pathway that proceeds through deamination of Nm to nicotinic acid (Na) by Nm deamidase and phosphoribosylation to nicotinic acid mononucleotide (NaMN), followed by adenylylation and amidation. Another is a two-step pathway that does not involve deamination and directly proceeds with the phosphoribosylation of Nm to nicotinamide mononucleotide (NMN), followed by adenylylation. Judging from genome sequence data, the hyperthermophilic archaeon Thermococcus kodakarensis is supposed to utilize the four-step pathway, but the fact that the adenylyltransferase encoded by TK0067 recognizes both NMN and NaMN also raises the possibility of a two-step salvage mechanism. Here, we examined the substrate specificity of the recombinant TK1676 protein, annotated as nicotinic acid phosphoribosyltransferase. The TK1676 protein displayed significant activity toward Na and phosphoribosyl pyrophosphate (PRPP) and only trace activity with Nm and PRPP. We further performed genetic analyses on TK0218 (quinolinic acid phosphoribosyltransferase) and TK1650 (Nm deamidase), involved in de novo biosynthesis and four-step salvage of NAD + , respectively. The ΔTK0218 mutant cells displayed growth defects in a minimal synthetic medium, but growth was fully restored with the addition of Na or Nm. The ΔTK0218 ΔTK1650 mutant cells did not display growth in the minimal medium, and growth was restored with the addition of Na but not Nm. The enzymatic and genetic analyses strongly suggest that NAD + salvage in T. kodakarensis requires deamination of Nm and proceeds through the four-step pathway. IMPORTANCE Hyperthermophiles must constantly deal with increased degradation rates of their biomolecules due to their high growth temperatures. Here, we identified the pathway that regenerates NAD + from nicotinamide (Nm) in the hyperthermophilic archaeon Thermococcus kodakarensis The organism utilizes a four-step pathway that initially hydrolyzes the amide bond of Nm to generate nicotinic acid (Na), followed by phosphoribosylation, adenylylation, and amidation. Although the two-step pathway, consisting of only phosphoribosylation of Nm and adenylylation, seems to be more efficient, Nm mononucleotide in the two-step pathway is much more thermolabile than Na mononucleotide, the corresponding intermediate in the four-step pathway. Although NAD + itself is thermolabile, this may represent an example of a metabolism that has evolved to avoid the use of thermolabile intermediates. Copyright © 2018 American Society for Microbiology.

  2. Multicomponent ternary cocrystals of the sulfonamide group with pyridine-amides and lactams.

    PubMed

    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.

  3. Pharmacological targeting of IDO-mediated tolerance for treating autoimmune disease.

    PubMed

    Penberthy, W Todd

    2007-04-01

    Cells at the maternal-fetal interface express indoleamine 2,3 dioxygenase (IDO) to consume all local tryptophan for the express purpose of starving adjacent maternal T cells of this most limiting and essential amino acid. This stops local T cell proliferation to ultimately result in the most dramatic example of immune tolerance, acceptance of the fetus. By contrast, inhibition of IDO using 1-methyl-tryptophan causes a sudden catastrophic rejection of the mammalian fetus. Immunomodulatory factors including IFNgamma, TNFalpha, IL-1, and LPS use IDO induction in responsive antigen presenting cells (APCs) also to transmit tolerogenic signals to T cells. Thus it makes sense to consider IDO induction towards tolerance for autoimmune diseases in general. Approaches to cell specific therapeutic IDO induction with NAD precursor supplementation to prevent the collateral non-T cell pathogenesis due to chronic TNFalpha-IDO activated tryptophan depletion in autoimmune diseases are reviewed. Tryptophan is an essential amino acid most immediately because it is the only precursor for the endogenous biosynthesis of nicotinamide adenine dinucleotide (NAD). Both autoimmune disease and the NAD deficiency disease pellagra occur in women at greater than twice the frequency of occurrence in men. The importance of IDO dysregulation manifest as autoimmune pellagric dementia is genetically illustrated for Nasu-Hakola Disease (or PLOSL), which is caused by a mutation in the IDO antagonizing genes TYROBP/DAP12 or TREM2. Loss of function leads to psychotic symptoms rapidly progressing to presenile dementia likely due to unchecked increases in microglial IDO expression, which depletes neurons of tryptophan causing neurodegeneration. Administration of NAD precursors rescued entire mental hospitals of dementia patients literally overnight in the 1930's and NAD precursors should help Nasu-Hakola patients as well. NAD depletion mediated by peroxynitrate PARP1 activation is one of the few established mechanisms of necrosis. Chronic elevation of TNFalpha leading to necrotic events by NAD depletion in autoimmune disease likely occurs via combination of persistent IDO activation and iNOS-peroxynitrate activation of PARP1 both of which deplete NAD. Pharmacological doses of NAD precursors repeatedly provide dramatic therapeutic benefit for rheumatoid arthritis, type 1 diabetes, multiple sclerosis, colitis, other autoimmune diseases, and schizophrenia in either the clinic or animal models. Collectively these observations support the idea that autoimmune disease may in part be considered as localized pellagra manifesting symptoms particular to the inflamed target tissues. Thus pharmacological doses of NAD precursors (nicotinic acid/niacin, nicotinamide/niacinamide, or nicotinamide riboside) should be considered as potentially essential to the therapeutic success of any IDO-inducing regimen for treating autoimmune diseases. Distinct among the NAD precursors, nicotinic acid specifically activates the g-protein coupled receptor (GPCR) GPR109a to produce the IDO-inducing tolerogenic prostaglandins PGE(2) and PGD(2). Next, PGD(2) is converted to the anti-inflammatory prostaglandin, 15d-PGJ(2). These prostaglandins exert potent anti-inflammatory activities through endogenous signaling mechanisms involving the GPCRs EP2, EP4, and DP1 along with PPARgamma respectively. Nicotinamide prevents type 1 diabetes and ameliorates multiple sclerosis in animal models, while nothing is known about the therapeutic potential of nicotinamide riboside. Alternatively the direct targeting of the non-redox NAD-dependent proteins using resveratrol to activate SIRT1 or PJ34 in order to inhibit PARP1 and prevent autoimmune pathogenesis are also given consideration.

  4. Saccharomyces cerevisiae engineered for xylose metabolism requires gluconeogenesis and the oxidative branch of the pentose phosphate pathway for aerobic xylose assimilation

    USDA-ARS?s Scientific Manuscript database

    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...

  5. Operation Brain Trauma Therapy

    DTIC Science & Technology

    2011-10-01

    Nicotinamide Choline Atorvastatin FK 506 Minocycline Lithium Rolipram Aniracetam Pentostatin...possible effects on CBF and trophic factor production. They confer benefit in experimental TBI.24,25 Atorvastatin , simvastatin, and lovastatin all show...promise after TBI in rats. Impressive benefit was seen with atorvastatin therapy by Wang et al.24 where improved perfor- mance on rotarod and Morris

  6. Effective immobilization of alcohol dehydrogenase on carbon nanoscaffolds for ethanol biofuel cell.

    PubMed

    Umasankar, Yogeswaran; Adhikari, Bal-Ram; Chen, Aicheng

    2017-12-01

    An efficient approach for immobilizing alcohol dehydrogenase (ADH) while enhancing its electron transfer ability has been developed using poly(2-(trimethylamino)ethyl methacrylate) (MADQUAT) cationic polymer and carbon nanoscaffolds. The carbon nanoscaffolds were comprised of single-walled carbon nanotubes (SWCNTs) wrapped with reduced graphene oxide (rGO). The ADH entrapped within the MADQUAT that was present on the carbon nanoscaffolds exhibited a high electron exchange capability with the electrode through its cofactor β-nicotinamide adenine dinucleotide hydrate and β-nicotinamide adenine dinucleotide reduced disodium salt hydrate (NAD + /NADH) redox reaction. The advantages of the carbon nanoscaffolds used as the support matrix and the MADQUAT employed for the entrapment of ADH versus physisorption were demonstrated via cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Our experimental results showed a higher electron transfer, electrocatalytic activity, and rate constant for MADQUAT entrapped ADH on the carbon nanoscaffolds. The immobilization of ADH using both MADQUAT and carbon nanoscaffolds exhibited strong potential for the development of an efficient bio-anode for ethanol powered biofuel cells. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. P7C3 neuroprotective chemicals block axonal degeneration and preserve function after traumatic brain injury.

    PubMed

    Yin, Terry C; Britt, Jeremiah K; De Jesús-Cortés, Héctor; Lu, Yuan; Genova, Rachel M; Khan, Michael Z; Voorhees, Jaymie R; Shao, Jianqiang; Katzman, Aaron C; Huntington, Paula J; Wassink, Cassie; McDaniel, Latisha; Newell, Elizabeth A; Dutca, Laura M; Naidoo, Jacinth; Cui, Huxing; Bassuk, Alexander G; Harper, Matthew M; McKnight, Steven L; Ready, Joseph M; Pieper, Andrew A

    2014-09-25

    The P7C3 class of neuroprotective aminopropyl carbazoles has been shown to block neuronal cell death in models of neurodegeneration. We now show that P7C3 molecules additionally preserve axonal integrity after injury, before neuronal cell death occurs, in a rodent model of blast-mediated traumatic brain injury (TBI). This protective quality may be linked to the ability of P7C3 molecules to activate nicotinamide phosphoribosyltransferase, the rate-limiting enzyme in nicotinamide adenine dinucleotide salvage. Initiation of daily treatment with our recently reported lead agent, P7C3-S243, 1 day after blast-mediated TBI blocks axonal degeneration and preserves normal synaptic activity, learning and memory, and motor coordination in mice. We additionally report persistent neurologic deficits and acquisition of an anxiety-like phenotype in untreated animals 8 months after blast exposure. Optimized variants of P7C3 thus offer hope for identifying neuroprotective agents for conditions involving axonal damage, neuronal cell death, or both, such as occurs in TBI. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  8. Discovery and Characterization of Novel Nonsubstrate and Substrate NAMPT Inhibitors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wilsbacher, Julie L.; Cheng, Min; Cheng, Dong

    Cancer cells are highly reliant on NAD+-dependent processes, including glucose metabolism, calcium signaling, DNA repair, and regulation of gene expression. Nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme for NAD+ salvage from nicotinamide, has been investigated as a target for anticancer therapy. Known NAMPT inhibitors with potent cell activity are composed of a nitrogen-containing aromatic group, which is phosphoribosylated by the enzyme. Here, we identified two novel types of NAM-competitive NAMPT inhibitors, only one of which contains a modifiable, aromatic nitrogen that could be a phosphoribosyl acceptor. Both types of compound effectively deplete cellular NAD+, and subsequently ATP, and produce cell deathmore » when NAMPT is inhibited in cultured cells for more than 48 hours. Careful characterization of the kinetics of NAMPT inhibition in vivo allowed us to optimize dosing to produce sufficient NAD+ depletion over time that resulted in efficacy in an HCT116 xenograft model. Our data demonstrate that direct phosphoribosylation of competitive inhibitors by the NAMPT enzyme is not required for potent in vitro cellular activity or in vivo antitumor efficacy. Mol Cancer Ther; 16(7); 1236–45.« less

  9. Enzymes inhibition and antidiabetic effect of isolated constituents from Dillenia indica.

    PubMed

    Kumar, Sunil; Kumar, Vipin; Prakash, Om

    2013-01-01

    This study was designed to investigate the enzyme inhibitory and antidiabetic activity for the constituents isolated from Dillenia indica. The leaves of D. indica were extracted with methanol and subjected to fractionation and chromatographic separation, which led to the isolation of seven compounds: betulinic acid (1), n-heptacosan-7-one (2), n-nonatriacontan-18-one (3), quercetin (4), β sitosterol (5), stigmasterol (6), and stigmasteryl palmitate (7). Among these isolates, compounds 1, 4, 5, and 6 were evaluated for in vitro enzyme inhibition and compounds 4, 5 and 6 were evaluated for antidiabetic activity in streptozotocin-nicotinamide induced diabetic mice. Compounds 1, 4, 5, and 6 showed 47.4, 55.2, 48.8, and 44.3% α -amylase inhibition, respectively, and 52.2, 78.2, 52.5, and 34.2% α -glucosidase inhibition, respectively, at the dose of 50 µg/kg. Compounds 4, 5 and 6 also showed significant (∗P < 0.05) antidiabetic activity in streptozotocin-nicotinamide induced diabetic mice at the dose of 10 mg/kg. These results provide evidence that Dillenia indica might be a potential source of antidiabetic agents.

  10. Renoprotective effect of Bacopa monnieri via inhibition of advanced glycation end products and oxidative stress in STZ-nicotinamide-induced diabetic nephropathy.

    PubMed

    Kishore, Lalit; Kaur, Navpreet; Singh, Randhir

    2016-10-01

    Hyperglycemia and oxidative stress are involved in the development of diabetic nephropathy (DN). This study was designed to evaluate the effect of alcohol and hydroalcohol extract of Bacopa monnieri and stigmasterol isolated from B. monnieri in the treatment of DN. Diabetes was induced in male wistar rats by streptozotocin (65 mg/kg i.p.) 15 min after nicotinamide (230 mg/kg, i.p.) administration. After 30 days, the rats were treated with different doses of extracts (100, 200, and 400 mg/kg) and stigmasterol (5 and 10 mg/kg) for 45 days to analyze their nephroprotective effect and produced significant attenuation in the serum glucose level, uric acid, creatinine, and lipid levels. Moreover, there is improvement in the level of superoxide dismutase (SOD), glutathione (GSH), and decrease in lipid peroxidation in terms of TBARS. The formation of AGEs in kidneys was also significantly reduced. These findings suggest that B. monnieri and its isolate (stigmasterol) might inhibit the progression of DN.

  11. Wld S protein requires Nmnat activity and a short N-terminal sequence to protect axons in mice.

    PubMed

    Conforti, Laura; Wilbrey, Anna; Morreale, Giacomo; Janeckova, Lucie; Beirowski, Bogdan; Adalbert, Robert; Mazzola, Francesca; Di Stefano, Michele; Hartley, Robert; Babetto, Elisabetta; Smith, Trevor; Gilley, Jonathan; Billington, Richard A; Genazzani, Armando A; Ribchester, Richard R; Magni, Giulio; Coleman, Michael

    2009-02-23

    The slow Wallerian degeneration (Wld(S)) protein protects injured axons from degeneration. This unusual chimeric protein fuses a 70-amino acid N-terminal sequence from the Ube4b multiubiquitination factor with the nicotinamide adenine dinucleotide-synthesizing enzyme nicotinamide mononucleotide adenylyl transferase 1. The requirement for these components and the mechanism of Wld(S)-mediated neuroprotection remain highly controversial. The Ube4b domain is necessary for the protective phenotype in mice, but precisely which sequence is essential and why are unclear. Binding to the AAA adenosine triphosphatase valosin-containing protein (VCP)/p97 is the only known biochemical property of the Ube4b domain. Using an in vivo approach, we show that removing the VCP-binding sequence abolishes axon protection. Replacing the Wld(S) VCP-binding domain with an alternative ataxin-3-derived VCP-binding sequence restores its protective function. Enzyme-dead Wld(S) is unable to delay Wallerian degeneration in mice. Thus, neither domain is effective without the function of the other. Wld(S) requires both of its components to protect axons from degeneration.

  12. High-Dose Nicotinamide Suppresses ROS Generation and Augments Population Expansion during CD8(+) T Cell Activation.

    PubMed

    Choi, Ho Jin; Jang, So-Young; Hwang, Eun Seong

    2015-10-01

    During T cell activation, mitochondrial content increases to meet the high energy demand of rapid cell proliferation. With this increase, the level of reactive oxygen species (ROS) also increases and causes the rapid apoptotic death of activated cells, thereby facilitating T cell homeostasis. Nicotinamide (NAM) has previously been shown to enhance mitochondria quality and extend the replicative life span of human fibroblasts. In this study, we examined the effect of NAM on CD8(+) T cell activation. NAM treatment attenuated the increase of mitochondrial content and ROS in T cells activated by CD3/CD28 antibodies. This was accompanied by an accelerated and higher-level clonal expansion resulting from attenuated apoptotic death but not increased division of the activated cells. Attenuation of ROS-triggered pro-apoptotic events and upregulation of Bcl-2 expression appeared to be involved. Although cells activated in the presence of NAM exhibited compromised cytokine gene expression, our results suggest a means to augment the size of T cell expansion during activation without consuming their limited replicative potential.

  13. 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)

    PubMed Central

    Blankfield, Adele

    2013-01-01

    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 disorders1 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. 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. PMID:23922501

  14. Effective treatment of mitochondrial myopathy by nicotinamide riboside, a vitamin B3.

    PubMed

    Khan, Nahid A; Auranen, Mari; Paetau, Ilse; Pirinen, Eija; Euro, Liliya; Forsström, Saara; Pasila, Lotta; Velagapudi, Vidya; Carroll, Christopher J; Auwerx, Johan; Suomalainen, Anu

    2014-06-01

    Nutrient availability is the major regulator of life and reproduction, and a complex cellular signaling network has evolved to adapt organisms to fasting. These sensor pathways monitor cellular energy metabolism, especially mitochondrial ATP production and NAD(+)/NADH ratio, as major signals for nutritional state. We hypothesized that these signals would be modified by mitochondrial respiratory chain disease, because of inefficient NADH utilization and ATP production. Oral administration of nicotinamide riboside (NR), a vitamin B3 and NAD(+) precursor, was previously shown to boost NAD(+) levels in mice and to induce mitochondrial biogenesis. Here, we treated mitochondrial myopathy mice with NR. This vitamin effectively delayed early- and late-stage disease progression, by robustly inducing mitochondrial biogenesis in skeletal muscle and brown adipose tissue, preventing mitochondrial ultrastructure abnormalities and mtDNA deletion formation. NR further stimulated mitochondrial unfolded protein response, suggesting its protective role in mitochondrial disease. These results indicate that NR and strategies boosting NAD(+) levels are a promising treatment strategy for mitochondrial myopathy. © 2014 The Authors. Published under the terms of the CC BY license.

  15. NAD+ and vitamin B3: from metabolism to therapies.

    PubMed

    Sauve, Anthony A

    2008-03-01

    The role of NAD(+) metabolism in health and disease is of increased interest as the use of niacin (nicotinic acid) has emerged as a major therapy for treatment of hyperlipidemias and with the recognition that nicotinamide can protect tissues and NAD(+) metabolism in a variety of disease states, including ischemia/reperfusion. In addition, a growing body of evidence supports the view that NAD(+) metabolism regulates important biological effects, including lifespan. NAD(+) exerts potent effects through the poly(ADP-ribose) polymerases, mono-ADP-ribosyltransferases, and the recently characterized sirtuin enzymes. These enzymes catalyze protein modifications, such as ADP-ribosylation and deacetylation, leading to changes in protein function. These enzymes regulate apoptosis, DNA repair, stress resistance, metabolism, and endocrine signaling, suggesting that these enzymes and/or NAD(+) metabolism could be targeted for therapeutic benefit. This review considers current knowledge of NAD(+) metabolism in humans and microbes, including new insights into mechanisms that regulate NAD(+) biosynthetic pathways, current use of nicotinamide and nicotinic acid as pharmacological agents, and opportunities for drug design that are directed at modulation of NAD(+) biosynthesis for treatment of human disorders and infections.

  16. The crystal structure of Pseudomonas aeruginosa exotoxin domain III with nicotinamide and AMP: conformational differences with the intact exotoxin.

    PubMed Central

    Li, M; Dyda, F; Benhar, I; Pastan, I; Davies, D R

    1995-01-01

    Domain III of Pseudomonas aeruginosa exotoxin A catalyses the transfer of ADP-ribose from NAD to a modified histidine residue of elongation factor 2 in eukaryotic cells, thus inactivating elongation factor 2. This domain III is inactive in the intact toxin but is active in the isolated form. We report here the 2.5-A crystal structure of this isolated domain crystallized in the presence of NAD and compare it with the corresponding structure in the intact Pseudomonas aeruginosa exotoxin A. We observe a significant conformational difference in the active site region from Arg-458 to Asp-463. Contacts with part of domain II in the intact toxin prevent the adoption of the isolated domain conformation and provide a structural explanation for the observed inactivity. Additional electron density in the active site region corresponds to separate AMP and nicotinamide and indicates that the NAD has been hydrolyzed. The structure has been compared with the catalytic domain of the diphtheria toxin, which was crystallized with ApUp. Images Fig. 1 PMID:7568123

  17. The NAD(+) precursor nicotinamide riboside enhances oxidative metabolism and protects against high-fat diet-induced obesity.

    PubMed

    Cantó, Carles; Houtkooper, Riekelt H; Pirinen, Eija; Youn, Dou Y; Oosterveer, Maaike H; Cen, Yana; Fernandez-Marcos, Pablo J; Yamamoto, Hiroyasu; Andreux, Pénélope A; Cettour-Rose, Philippe; Gademann, Karl; Rinsch, Chris; Schoonjans, Kristina; Sauve, Anthony A; Auwerx, Johan

    2012-06-06

    As NAD(+) is a rate-limiting cosubstrate for the sirtuin enzymes, its modulation is emerging as a valuable tool to regulate sirtuin function and, consequently, oxidative metabolism. In line with this premise, decreased activity of PARP-1 or CD38-both NAD(+) consumers-increases NAD(+) bioavailability, resulting in SIRT1 activation and protection against metabolic disease. Here we evaluated whether similar effects could be achieved by increasing the supply of nicotinamide riboside (NR), a recently described natural NAD(+) precursor with the ability to increase NAD(+) levels, Sir2-dependent gene silencing, and replicative life span in yeast. We show that NR supplementation in mammalian cells and mouse tissues increases NAD(+) levels and activates SIRT1 and SIRT3, culminating in enhanced oxidative metabolism and protection against high-fat diet-induced metabolic abnormalities. Consequently, our results indicate that the natural vitamin NR could be used as a nutritional supplement to ameliorate metabolic and age-related disorders characterized by defective mitochondrial function. Copyright © 2012 Elsevier Inc. All rights reserved.

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

    PubMed

    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.

  19. Mitochondrial inhibitor models of Huntington's disease and Parkinson's disease induce zinc accumulation and are attenuated by inhibition of zinc neurotoxicity in vitro or in vivo.

    PubMed

    Sheline, Christian T; Zhu, Julia; Zhang, Wendy; Shi, Chunxiao; Cai, Ai-Li

    2013-01-01

    Inhibition of mitochondrial function occurs in many neurodegenerative diseases, and inhibitors of mitochondrial complexes I and II are used to model them. The complex II inhibitor, 3-nitroproprionic acid (3-NPA), kills the striatal neurons susceptible in Huntington's disease. The complex I inhibitor N-methyl-4-phenylpyridium (MPP(+)) and 6-hydroxydopamine (6-OHDA) are used to model Parkinson's disease. Zinc (Zn(2+)) accumulates after 3-NPA, 6-OHDA and MPP(+) in situ or in vivo. We will investigate the role of Zn(2+) neurotoxicity in 3-NPA, 6-OHDA and MPP(+). Murine striatal/midbrain tyrosine hydroxylase positive, or near-pure cortical neuronal cultures, or animals were exposed to 3-NPA or MPP(+) and 6-OHDA with or without neuroprotective compounds. Intracellular zinc ([Zn(2+)](i)), nicotinamide adenine dinucleotide (NAD(+)), NADH, glycolytic intermediates and neurotoxicity were measured. We showed that compounds or genetics which restore NAD(+) and attenuate Zn(2+) neurotoxicity (pyruvate, nicotinamide, NAD(+), increased NAD(+) synthesis, sirtuin inhibition or Zn(2+) chelation) attenuated the neuronal death induced by these toxins. The increase in [Zn(2+)](i) preceded a reduction in the NAD(+)/NADH ratio that caused a reversible glycolytic inhibition. Pyruvate, nicotinamide and NAD(+) reversed the reductions in the NAD(+)/NADH ratio, glycolysis and neuronal death after challenge with 3-NPA, 6-OHDA or MPP(+), as was previously shown for exogenous Zn(2+). To test efficacy in vivo, we injected 3-NPA into the striatum of rats and systemically into mice, with or without pyruvate. We observed early striatal Zn(2+) fluorescence, and pyruvate significantly attenuated the 3-NPA-induced lesion and restored behavioral scores. Together, these studies suggest that Zn(2+) accumulation caused by MPP(+) and 3-NPA is a novel preventable mechanism of the resultant neurotoxicity. Copyright © 2012 S. Karger AG, Basel.

  20. Nicotinamide Phosphoribosyltransferase Upregulation by Phenylephrine Reduces Radiation Injury in Submandibular Gland

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Xiang, Bin, E-mail: xiangbin72@163.com; Han, Lichi; Wang, Xinyue

    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 determinedmore » 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, which help to understand the mechanism of the cytoprotective role of phenylephrine on irradiated tissues.« less

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

    PubMed

    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 reverse diet-induced obesity and validate NNMT as a viable target to treat obesity and related metabolic conditions. Increased flux of key cellular energy regulators, including NAD + and SAM, may potentially define the therapeutic mechanism-of-action of NNMT inhibitors. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Head to Head Comparison of Short-Term Treatment with the NAD(+) Precursor Nicotinamide Mononucleotide (NMN) and 6 Weeks of Exercise in Obese Female Mice.

    PubMed

    Uddin, Golam M; Youngson, Neil A; Sinclair, David A; Morris, Margaret J

    2016-01-01

    Obesity is well known to be a major cause of several chronic metabolic diseases, which can be partially counteracted by exercise. This is due, in part, to an upregulation of mitochondrial activity through increased nicotinamide adenine dinucleotide (NAD(+)). Recent studies have shown that NAD(+) levels can be increased by using the NAD(+) precursor, nicotinamide mononucleotide (NMN) leading to the suggestion that NMN could be a useful intervention in diet related metabolic disorders. In this study we compared the metabolic, and especially mitochondrial-associated, effects of exercise and NMN in ameliorating the consequences of high-fat diet (HFD) induced obesity in mice. Sixty female 5 week old C57BL6/J mice were allocated across five groups: Chow sedentary: CS; Chow exercise: CEX; HFD sedentary: HS; HFD NMN: HNMN; HFD exercise: HEX (12/group). After 6 weeks of diet, exercise groups underwent treadmill exercise (15 m/min for 45 min), 6 days per week for 6 weeks. NMN or vehicle (500 mg/kg body weight) was injected (i.p.) daily for the last 17 days. No significant alteration in body weight was observed in response to exercise or NMN. The HFD significantly altered adiposity, glucose tolerance, plasma insulin, NADH levels and citrate synthase activity in muscle and liver. HEX and HNMN groups both showed significantly improved glucose tolerance compared to the HS group. NAD(+) levels were increased significantly both in muscle and liver by NMN whereas exercise increased NAD(+) only in muscle. Both NMN and exercise ameliorated the HFD-induced reduction in liver citrate synthase activity. However, exercise, but not NMN, ameliorated citrate synthase activity in muscle. Overall these data suggest that while exercise and NMN-supplementation can induce similar reversal of the glucose intolerance induced by obesity, they are associated with tissue-specific effects and differential alterations to mitochondrial function in muscle and liver.

  3. Perinatal asphyxia leads to PARP-1 overactivity, p65 translocation, IL-1β and TNF-α overexpression, and apoptotic-like cell death in mesencephalon of neonatal rats: prevention by systemic neonatal nicotinamide administration.

    PubMed

    Neira-Peña, T; Rojas-Mancilla, E; Munoz-Vio, V; Perez, R; Gutierrez-Hernandez, M; Bustamante, D; Morales, P; Hermoso, M A; Gebicke-Haerter, P; Herrera-Marschitz, M

    2015-05-01

    Perinatal asphyxia (PA) is a leading cause of neuronal damage in newborns, resulting in long-term neurological and cognitive deficits, in part due to impairment of mesostriatal and mesolimbic neurocircuitries. The insult can be as severe as to menace the integrity of the genome, triggering the overactivation of sentinel proteins, including poly (ADP-ribose) polymerase-1 (PARP-1). PARP-1 overactivation implies increased energy demands, worsening the metabolic failure and depleting further NAD(+) availability. Using a global PA rat model, we report here evidence that hypoxia increases PARP-1 activity, triggering a signalling cascade leading to nuclear translocation of the NF-κB subunit p65, modulating the expression of IL-1β and TNF-α, pro-inflammatory molecules, increasing apoptotic-like cell death in mesencephalon of neonate rats, monitored with Western blots, qPCR, TUNEL and ELISA. PARP-1 activity increased immediately after PA, reaching a maximum 1-8 h after the insult, while activation of the NF-κB signalling pathway was observed 8 h after the insult, with a >twofold increase of p65 nuclear translocation. IL-1β and TNF-α mRNA levels were increased 24 h after the insult, together with a >twofold increase in apoptotic-like cell death. A single dose of the PARP-1 inhibitor nicotinamide (0.8 mmol/kg, i.p.), 1 h post delivery, prevented the effect of PA on PARP-1 activity, p65 translocation, pro-inflammatory cytokine expression and apoptotic-like cell death. The present study demonstrates that PA leads to PARP-1 overactivation, increasing the expression of pro-inflammatory cytokines and cell death in mesencephalon, effects prevented by systemic neonatal nicotinamide administration, supporting the idea that PARP-1 inhibition represents a therapeutic target against the effects of PA.

  4. Nicotinamide riboside, an unusual, non-typical, substrate of purified purine-nucleoside phosphorylases.

    PubMed

    Wielgus-Kutrowska, B; Kulikowska, E; Wierzchowski, J; Bzowska, A; Shugar, D

    1997-01-15

    Nicotinamide 1-beta-D-riboside (Nir), the cationic, reducible moiety of the coenzyme NAD+, has been confirmed as an unusual substrate for purified purine-nucleoside phosphorylase (PNP) from a mammalian source (calf spleen). It is also a substrate of the enzyme from Escherichia coli. The Km values at pH 7, 1.48 mM and 0.62 mM, respectively, were 1-2 orders of magnitude higher than for the natural substrate inosine, but the Vmax values were comparable, 96% and 35% that for Ino. The pseudo first-order rate constants, Vmax/Km, were 1.1% and 2.5% for the calf spleen and E. coli enzymes. The aglycon, nicotinamide, was neither a substrate nor an inhibitor of PNP. Nir was a weak inhibitor of inosine phosphorolysis catalyzed by both enzymes, with Ki values close to the Km for its phosphorolysis, consistent with simple competitive inhibition; this was further confirmed by Dixon plots. Phosphorolysis of the fluorescent positively charged substrate 7-methylguanosine was also inhibited in a competitive manner by both Ino and Nir. Phosphorolysis of Nir by both enzymes was inhibited competitively by several specific inhibitors of calf spleen and E. coli PNP, with Ki values similar to those for inhibition of other natural substrates. The pH dependence of the kinetic constants for the phosphorolysis of Nir and of a variety of other substrates, was extensively investigated, particularly in the alkaline pH range, where Nir exhibited abnormally high substrate activity relative to the reduced reaction rates of both enzymes towards other anionic or neutral substrates. The overall results are discussed in relation to present concepts regarding binding and phosphorolysis of substrates by PNP based on crystallographic data of enzyme-inhibitor complexes, and current studies on enzymatic and nonenzymatic mechanisms of the cleavage of the Nir glycosidic bond.

  5. Nicotinamide riboside attenuates alcohol induced liver injuries via activation of SirT1/PGC-1α/mitochondrial biosynthesis pathway.

    PubMed

    Wang, Sufan; Wan, Ting; Ye, Mingtong; Qiu, Yun; Pei, Lei; Jiang, Rui; Pang, Nengzhi; Huang, Yuanling; Liang, Baoxia; Ling, Wenhua; Lin, Xiaojun; Zhang, Zhenfeng; Yang, Lili

    2018-07-01

    Nicotinamide riboside (NR) is a nicotinamide adenine dinucleotide (NAD + ) precursor which is present in foods such as milk and beer. It was reported that NR can prevent obesity, increase longevity, and promote liver regeneration. However, whether NR can prevent ethanol-induced liver injuries is not known. This study aimed to explore the effect of NR on ethanol induced liver injuries and the underlying mechanisms. We fed C57BL/6 J mice with Lieber-DeCarli ethanol liquid diet with or without 400 mg/kg·bw NR for 16 days. Liver injuries and SirT1-PGC-1α-mitochondrial function were analyzed. In in vitro experiments, HepG2 cells (CYP2E1 over-expressing cells) were incubated with ethanol ± 0.5 mmol/L NR. Lipid accumulation and mitochondrial function were compared. SirT1 knockdown in HepG2 cells were further applied to confirm the role of SirT1 in the protection of NR on lipid accumulation. We found that ethanol significantly decreased the expression and activity of hepatic SirT1 and induced abnormal expression of enzymes of lipid metabolism in mice. Both in vivo and in vitro experiments showed that NR activated SirT1 through increasing NAD + levels, decreased oxidative stress, increased deacetylation of PGC-1α and mitochondrial function. In SirT1 knockdown HepG2 cells, NR lost its ability in enhancing mitochondrial function, and its protection against lipid accumulation induced by ethanol. NR can protect against ethanol induced liver injuries via replenishing NAD + , reducing oxidative stress, and activating SirT1-PGC-1α-mitochondrial biosynthesis. Our data indicate that SirT1 plays an important role in the protection of NR against lipid accumulation and mitochondrial dysfunctions induced by ethanol. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  6. [Reference values of niacin for the Venezuelan population].

    PubMed

    Carias, Diamela; García-Casal, María Nieves; Soto de Sanabria, Ingrid; López Rodríguez, Ana Victoria

    2013-12-01

    Niacin is a water soluble vitamin, also known as nicotinic acid or Vitamin B3. Nicotinamide is a derivative of niacin (amide of nicotinic acid), and is used by the body to produce the coenzyme nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP), In preparing this review about the niacin requirements for Venezuela, it was found that there is not enough national data to establish recommendations, therefore, as in the 2000 review of the Venezuelan Recommended Dietary Allowances (RDAs), the actual recommendations for intake of niacin, are based on those reported for the United States population. The RDAs for Venezuela are: 2-4 mg/day for infants less than 1 year old, 6-8 mg/day for children between 1 and 8 years, 12 mg/day for children between 9 and 13 years, 14 mg/day for adolescents and female adults, 16 mg/day for adolescents and adult males, 18 mg/day during pregnancy and 17 mg/day during lactation. The estimated average requirement (EAR) is: 6-9 mg/day for children, 11 mg/ day for adolescents and female adults and 12 mg/day for adolescents and adult males, increasing to 14 mg/day during pregnancy and to 13 mg/day during lactation. The niacin Tolerable Upper Intake Levels (UL) are: 10 mg/day for children between 1 and 3 years, 15 mg/day for children between 4 and 8 years, 20 mg/day for children between 9 and 13 years, 30 mg/day for adolescents and 35 mg/day for adults. It is necessary to perform studies where the nutritional status of this vitamin is evaluated for different population groups, including not only the estimation of consumption, but the use of biochemical indicators, such as measuring the levels of the coenzymes NAD and NADP in erythrocytes or whole blood and determination of the major urinary metabolites of the vitamin.

  7. Enzymatic Basis for Differentiation of Rhizobium into Fast- and Slow-Growing Groups

    PubMed Central

    Drets, G. Martinez-De; Arias, A.

    1972-01-01

    Glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, and other enzymes related to carbohydrate metabolism were studied in rhizobia. A nicotinamide adenine dinucleotide phosphate-6-phosphogluconate dehydrogenase was detected in strains of the fast-growing group of Rhizobium but not in strains of the slow-growing group. An enzymatic differentiation of rhizobia was established. PMID:4400417

  8. Pleiotropic effects of the sirtuin inhibitor sirtinol involves concentration-dependent modulation of multiple nuclear receptor-mediated pathways in the androgen-responsive prostate cancer cell LNCaP

    USDA-ARS?s Scientific Manuscript database

    Sirtinol, a purported specific inhibitor of the nicotinamide adenine dinucleotide (NAD)-dependent type III histone deacetylase (also known as sirtuin), has been used extensively to identify chemopreventive/chemotherapeutic agents that modulate the activity of this group of enzymes. However, the mole...

  9. Ultra-performance liquid chromatography tandem mass-spectrometry (uplc-ms/ms) for the rapid, simultaneous analysis of thiamin, riboflavin, flavin adenine dinucleotide, nicotinamide and pyridoxal in human milk

    USDA-ARS?s Scientific Manuscript database

    A novel, rapid and sensitive Ultra Performance Liquid-Chromatography tandem Mass-Spectrometry (UPLC-MS/MS) method for the simultaneous determination of several B-vitamins in human milk was developed. Resolution by retention time or multiple reaction monitoring (MRM) for thiamin, riboflavin, flavin a...

  10. Quantitative determination of a-Arbutin, ß-Arbutin, Kojic acid, nicotinamide, hydroquinone, resorcinol, 4-methoxyphenol, 4-ethoxyphenol and ascorbic acid from skin whitening Products by HPLC-UV

    USDA-ARS?s Scientific Manuscript database

    Development of an analytical method for the simultaneous determination of multifarious skin whitening agents will provide an efficient tool to analyze skin whitening cosmetics. An HPLC-UV method was developed for quantitative analysis of six commonly used whitening agents, a-arbutin, ß-arbutin, koji...

  11. ENZYME ACTIVITIES DURING THE ASEXUAL CYCLE OF NEUROSPORA CRASSA

    PubMed Central

    Stine, G. J.

    1968-01-01

    Three enzymes, (a) nicotinamide adenine diphosphate-dependent glutamic dehydrogenase (NAD enzyme), (b) nictoinamide adenine triphosphate-dependent glutamic dehydrogenase (NADP enzyme), and (c) nicotinamide-adenine dinucleotidase (NADase), were measured in separate extracts of Neurospora crassa grown in Vogel's medium N and medium N + glutamate. Specific activities and total units per culture of each enzyme were determined at nine separate intervals phased throughout the asexual cycle. The separate dehydrogenases were lowest in the conidia, increased slowly during germination, and increased rapidly during logarithmic mycelial growth. The amounts of these enzymes present during germination were small when compared with those found later during the production of the conidiophores. The NAD enzyme may be necessary for pregermination synthesis. The NADP-enzyme synthesis was associated with the appearance of the germ tube. Although higher levels of the dehydrogenases in the conidiophores resulted in more enzyme being found in the differentiated conidia, the rate of germination was uneffected. The greatest activity for the NADase enzyme was associated with the conidia, early phases of germination, and later production of new conidia. NADase decreased significantly with the onset of logarithmic growth, remained low during the differentiation of conidiophores, and increased considerably as the conidiophores aged. PMID:4384627

  12. NMR-based metabonomic analysis of MnO-embedded iron oxide nanoparticles as potential dual-modal contrast agents

    NASA Astrophysics Data System (ADS)

    Li, Jinquan; Zhou, Zijian; Feng, Jianghua; Cai, Shuhui; Gao, Jinhao; Chen, Zhong

    2014-05-01

    MnO-embedded iron oxide nanoparticles (MnIO-NPs) can be treated as potential dual-modal contrast agents. However, their overall bio-effects and potential toxicity remain unknown. In this study, the metabolic effects of MnIO-NPs (dosed at 1 and 5 mg Fe/kg) on Sprague-Dawley rats were investigated using metabonomic analysis, histopathological examination, and conventional biochemical analysis. The histological changes included a focal inflammation in the liver at high-dose and a slightly enlarged area of splenic white pulp after 48 h post-dose. Blood biochemical analysis showed that albumin, globulins, aspartate aminotransferase, lactate dehydrogenase, blood urea nitrogen, and glucose changed distinctly compared to the control. The metabonomic analysis of body fluids (serum and urine) and tissues (liver, kidney, and spleen) indicated that MnIO-NPs induced metabolic perturbation in rats including energy, nucleotides, amino acids and phospholipid metabolisms. Besides, the variations of supportive nutrients: valine, leucine, isoleucine, nicotinamide adenine dinucleotide (phosphate), and nicotinamide, and the conjugation substrates: glycine, taurine, glutamine, glutathione, and methyl donors (formate, sarcosine, dimethylglycine, choline, and betaine) were involved in detoxification reaction of MnIO-NPs. The obtained information would provide identifiable ground for the candidate selection and optimization.

  13. Photosensitized oxidation of nicotinamide adenine dinucleotide by diethoxyphosphorus(V)tetraphenylporphyrin and its fluorinated derivative: Possibility of chain reaction

    NASA Astrophysics Data System (ADS)

    Hirakawa, Kazutaka; Murata, Atsushi

    2018-01-01

    Water-soluble porphyrins, diethoxyphosphorus(V)tetraphenylporphyrin (EtP(V)TPP) and its fluorinated analogue (FEtP(V)TPP), decreased the typical absorption around 340 nm of nicotinamide adenine dinucleotide (NADH) under visible light irradiation, indicating oxidative decomposition. A singlet oxygen quencher, sodium azide, and a triplet quencher, potassium iodide, slightly inhibited photosensitized NADH oxidation. However, these inhibitory effects were very small. Furthermore, the fluorescence lifetime of these P(V)porphyrins was decreased by NADH, suggesting the contribution of electron transfer to the singlet excited (S1) state of P(V)porphyrin. The redox potential measurement supports the electron transfer-mediated oxidation of NADH. The quantum yields of NADH photodecomposition by P(V)porphyrins could be estimated from the kinetic data and the effect of these quenchers on NADH oxidation. The obtained values suggest that the electron accepting by the S1 states of P(V)porphyrins triggers a chain reaction of NADH oxidation. This photosensitized reaction may play an important role in the photocytotoxicity of P(V)porphyrins. The axial ligand fluorination of P(V)porphyrins improved electron accepting ability. However, fluorination slightly suppressed static interaction with NADH, resulting in decreased oxidation quantum yield.

  14. Deproteinization is Necessary for the Accurate Determination of Ammonia Levels by Glutamate Dehydrogenase Assay in Blood Plasma From Subjects With Liver Injury.

    PubMed

    Vodenicarovova, Melita; Skalska, Hana; Holecek, Milan

    2017-11-08

    To determine the effect of presence of high concentrations of nicotinamide adenine dinucleotide (NADH)- and nicotinamide adenine dinucleotide phosphate (NADPH)-consuming enzymes on the accuracy of glutamate dehydrogenase (GLDH) assay for ammonia. We measured ammonia concentrations using GLDH and NADH or NADPH in blood-plasma specimens and specimens deproteinized by sulfosalicylic acid from CCl4-treated or control rats. The nonspecific oxidation of NADH and NADPH was measured in mixtures without GLDH. We observed a gradual decrease (~0.5%) in absorbance in the plasma of controls after the addition of NADH but not after adding NADPH. The decrease in absorbance in plasma of CCl4-treated animals was 13.2% and 5.2% after the addition of NADH and NADPH, respectively. The decrease in absorbance was not detected in deproteinized specimens. The values of ammonia concentration were higher in the plasma specimens compared with the deproteinized ones. Deproteinization is necessary for accurate measurement of ammonia using GLDH assay in the blood plasma of subjects with liver injury. © American Society for Clinical Pathology, 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  15. Radiosterilization of drugs in aqueous solutions may be achieved by the use of radioprotective excipients.

    PubMed

    Maquille, Aubert; Jiwan, Jean-Louis Habib; Tilquin, Bernard

    2008-02-12

    The aim of this study was to assess the feasibility of radiosterilization of drugs aqueous solutions and to evaluate the effects of some additives, such as mannitol, nicotinamide and pyridoxine, which might protect the drug from degradation. Metoclopramide was selected as a model drug. The structures of the degradation products were determined to gain insight on the radiolysis mechanisms in aqueous solution in order to design strategies to lower the drug degradation. Metoclopramide hydrochloride aqueous solutions with and without excipients were irradiated either with gamma rays or high-energy electrons. HPLC-DAD was used to measure the loss of chemical potency and to quantify the degradation products which were also characterized by LC-APCI-MS-MS. Metoclopramide recovery for gamma and electron beam-irradiated solutions containing either mannitol, pyridoxine or nicotinamide meets the pharmacopoeial specifications for metoclopramide content up to a 15 kGy irradiation so that metoclopramide solutions containing these excipients might be radiosterilized at 15 kGy either with gamma rays or high-energy electrons. Structures are proposed for the majority of radiolysis products. Similar radiolysis products were detected for gamma and electron beam irradiations but the chromatographic profiles were different (differences in the distribution of radiolysis products).

  16. Converting NADH to NAD+ by nicotinamide nucleotide transhydrogenase as a novel strategy against mitochondrial pathologies during aging.

    PubMed

    Olgun, Abdullah

    2009-08-01

    Mitochondrial DNA defects are involved supposedly via free radicals in many pathologies including aging and cancer. But, interestingly, free radical production was not found increased in prematurely aging mice having higher mutation rate in mtDNA. Therefore, some other mechanisms like the increase of mitochondrial NADH/NAD(+) and ubiquinol/ubiquinone ratios, can be in action in respiratory chain defects. NADH/NAD(+) ratio can be normalized by the activation or overexpression of nicotinamide nucleotide transhydrogenase (NNT), a mitochondrial enzyme catalyzing the following very important reaction: NADH + NADP(+ )<--> NADPH + NAD(+). The products NAD(+) and NADPH are required in many critical biological processes, e.g., NAD(+) is used by histone deacetylase Sir2 which regulates longevity in different species. NADPH is used in a number of biosynthesis reactions (e.g., reduced glutathione synthesis), and processes like apoptosis. Increased ubiquinol/ubiquinone ratio interferes the function of dihydroorotate dehydrogenase, the only mitochondrial enzyme involved in ubiquinone mediated de novo pyrimidine synthesis. Uridine and its prodrug triacetyluridine are used to compensate pyrimidine deficiency but their bioavailability is limited. Therefore, the normalization of the ubiquinol/ubiquinone ratio can be accomplished by allotopic expression of alternative oxidase, a mitochondrial ubiquinol oxidase which converts ubiquinol to ubiquinone.

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

    PubMed

    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.

  18. Cobalt dipicolinate complexes with nicotinamide and isonicotinamide ligands: Syntheses, crystal structures, spectroscopic, thermal and voltammetric studies

    NASA Astrophysics Data System (ADS)

    Uçar, İbrahim; Bulut, Ahmet; Karadağ, Ahmet; Kazak, Canan

    2007-06-01

    Two new dipicolinate complexes of cobalt, [Co(dpc)(na)(H 2O) 2]·H 2O ( 1) and [Co(dpc)(ina)(H 2O) 2] ( 2) [dpc is dipicolinate or pyridine-2,6-dicarboxylate, na is nicotinamide and ina is isonicotinamide], have been prepared and characterized by thermal analysis, IR spectroscopy and X-ray diffraction techniques. The complex ( 1) crystallizes in triclinic system, whereas the complex ( 2) crystallizes in monoclinic system. The Co(II) ion in both complexes is bonded to dpc ligand through pyridine N atom together with one O atom of each carboxylate group, two aqua ligands and N pyridine atom of na ( 1) or ina ( 2), forming the distorted octahedral geometry. The complex molecules ( 1) and ( 2) are connected via N sbnd H⋯O and O sbnd H⋯O hydrogen bonds. The voltammetric behaviour of complexes ( 1) and ( 2) was also investigated in DMSO (dimethylsulfoxide) solution by cyclic voltammetry using n-Bu 4NClO 4 supporting electrolyte. The complexes exhibit only metal centered electroactivity in the potential ±1.25 V versus Ag/AgCl reference electrode.

  19. Investigation of the effect of hydroxypropyl methylcellulose on the phase transformation and release profiles of carbamazepine-nicotinamide cocrystal.

    PubMed

    Li, Mingzhong; Qiu, Shi; Lu, Yan; Wang, Ke; Lai, Xiaojun; Rehan, Mohammad

    2014-09-01

    The aim of this work was to investigate the influence of hydroxypropyl methylcellulose (HPMC) on the phase transformation and release profile of carbamazepine-nicotinamide (CBZ-NIC) cocrystal in solution and in sustained release matrix tablets. The polymorphic transitions of the CBZ-NIC cocrystal and its crystalline properties were examined by differential scanning calorimetry (DSC), X-ray powder diffraction (XRPD), Raman spectroscopy, and scanning electron microscopy (SEM). The apparent CBZ solubility and dissolution rate of CBZ-NIC cocrystal were constant in different concentrations of HPMC solutions. In a lower percentage of HPMC in the matrix tablets, the CBZ release profile of the CBZ-NIC cocrystal was nonlinear and declined over time. With an increased HPMC content in the tablets, the CBZ-NIC cocrystal formulation showed a significantly higher CBZ release rate in comparison with the other two formulations of CBZ III and the physical mixture. Because of a significantly improved dissolution rate of the CBZ-NIC cocrystal, the rate of CBZ entering into solution is significantly faster than the rate of formation of the CBZ-HPMC soluble complex in solution, leading to a higher supersaturation level of CBZ and subsequently precipitation of CBZ dihydrate.

  20. Initial dissolution kinetics of cocrystal of carbamazepine with nicotinamide.

    PubMed

    Hattori, Yusuke; Sato, Maiko; Otsuka, Makoto

    2015-11-01

    Objectives of this study are investigating the initial dissolution kinetics of the cocrystal of carbamazepine (CBZ) with nicotinamide (NIC) and understanding its initial dissolution process. Cocrystal solids of CBZ with NIC were prepared by co-milling and solvent evaporation methods. The formation of cocrystal solid was verified via X-ray diffraction measurement. Dissolution tests of the solids were performed using an original flow cell and ultraviolet-visible spectroscopic detector. The spectra monitored in situ were analyzed to determine the dissolved compounds separately using the classical least squares regression method. The initial dissolution profiles were interpreted using simultaneous model of dissolution and phase changes. In the initial dissolution, CBZ in the cocrystal structure dissolved in water and it was suggested that CBZ reached a metastable intermediate state simultaneously with dissolution. The cocrystal solid prepared by solvent evaporation provided a higher rate constant of the phase change than that prepared by co-milling. Our results thus support the use of evaporation as the method of choice to produce ordered cocrystal structures. We suggest that CBZ forms dihydrate during the dissolution process; however, during the initial phase of dissolution, CBZ changes to a metastable intermediate phase. © 2015 Royal Pharmaceutical Society.

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

    PubMed

    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.

  2. Regulation of the Biosynthesis of Amino Acids of the Aspartate Family in Coliform Bacteria and Pseudomonads

    PubMed Central

    Cohen, G. N.; Stanier, R. Y.; Bras, Gisele Le

    1969-01-01

    The control of aspartokinase and homoserine dehydrogenase activities was compared in aerobic and fermentative pseudomonads (genera Pseudomonas and Aeromonas), and in coliform bacteria representative of the principal genera of the Enterobacteriaceae. Isofunctional aspartokinases subject to independent end-product control occur in the Enterobacteriaceae and in Aeromonas. In Pseudomonas, there appears to be a single aspartokinase, subject to concerted feedback inhibition by lysine and threonine. Within this genus, the sensitivity of aspartokinase to the single allosteric inhibitors varies considerably: the aspartokinase of the acidovorans group is little affected by the single inhibitors, whereas that of the fluorescent group is severely inhibited by either amino acid at high concentration. In all bacteria examined, homoserine dehydrogenase activity is inhibited by threonine; inhibition is more severe in aerobic pseudomonads than in the other groups. In most of the bacteria examined, either nicotinamide adenine dinucleotide (NAD) or nicotinamide adenine dinucleotide phosphate can serve as a cofactor for this enzyme, though the relative activity with the two pyridine nucleotides varies widely. Aerobic pseudomonads of the acidovorans group contain a homoserine dehydrogenase that is absolutely specific for NAD. The taxonomic implications of these findings are discussed. PMID:4391829

  3. Enzymes Inhibition and Antidiabetic Effect of Isolated Constituents from Dillenia indica

    PubMed Central

    Kumar, Sunil; Kumar, Vipin; Prakash, Om

    2013-01-01

    Aims. This study was designed to investigate the enzyme inhibitory and antidiabetic activity for the constituents isolated from Dillenia indica. Methods. The leaves of D. indica were extracted with methanol and subjected to fractionation and chromatographic separation, which led to the isolation of seven compounds: betulinic acid (1), n-heptacosan-7-one (2), n-nonatriacontan-18-one (3), quercetin (4), β sitosterol (5), stigmasterol (6), and stigmasteryl palmitate (7). Among these isolates, compounds 1, 4, 5, and 6 were evaluated for in vitro enzyme inhibition and compounds 4, 5 and 6 were evaluated for antidiabetic activity in streptozotocin-nicotinamide induced diabetic mice. Results. Compounds 1, 4, 5, and 6 showed 47.4, 55.2, 48.8, and 44.3% α-amylase inhibition, respectively, and 52.2, 78.2, 52.5, and 34.2% α-glucosidase inhibition, respectively, at the dose of 50 µg/kg. Compounds 4, 5 and 6 also showed significant (∗P < 0.05) antidiabetic activity in streptozotocin-nicotinamide induced diabetic mice at the dose of 10 mg/kg. Conclusion. These results provide evidence that Dillenia indica might be a potential source of antidiabetic agents. PMID:24307994

  4. Primitive Photosynthetic Architectures Based on Self-Organization and Chemical Evolution of Amino Acids and Metal Ions.

    PubMed

    Liu, Kai; Ren, Xiaokang; Sun, Jianxuan; Zou, Qianli; Yan, Xuehai

    2018-06-01

    The emergence of light-energy-utilizing metabolism is likely to be a critical milestone in prebiotic chemistry and the origin of life. However, how the primitive pigment is spontaneously generated still remains unknown. Herein, a primitive pigment model based on adaptive self-organization of amino acids (Cystine, Cys) and metal ions (zinc ion, Zn 2+ ) followed by chemical evolution under hydrothermal conditions is developed. The resulting hybrid microspheres are composed of radially aligned cystine/zinc (Cys/Zn) assembly decorated with carbonate-doped zinc sulfide (C-ZnS) nanocrystals. The part of C-ZnS can work as a light-harvesting antenna to capture ultraviolet and visible light, and use it in various photochemical reactions, including hydrogen (H 2 ) evolution, carbon dioxide (CO 2 ) photoreduction, and reduction of nicotinamide adenine dinucleotide (NAD + ) to nicotinamide adenine dinucleotide hydride (NADH). Additionally, guest molecules (e.g., glutamate dehydrogenase, GDH) can be encapsulated within the hierarchical Cys/Zn framework, which facilitates sustainable photoenzymatic synthesis of glutamate. This study helps deepen insight into the emergent functionality (conversion of light energy) and complexity (hierarchical architecture) from interaction and reaction of prebiotic molecules. The primitive pigment model is also promising to work as an artificial photosynthetic microreactor.

  5. Ebselen Reversibly Inhibits Human Glutamate Dehydrogenase at the Catalytic Site.

    PubMed

    Jin, Yanhong; Li, Di; Lu, Shiying; Zhao, Han; Chen, Zhao; Hou, Wei; Ruan, Benfang Helen

    Human glutamate dehydrogenase (GDH) plays an important role in neurological diseases, tumor metabolism, and hyperinsulinism-hyperammonemia syndrome (HHS). However, there are very few inhibitors known for human GDH. Recently, Ebselen was reported to crosslink with Escherichia coli GDH at the active site cysteine residue (Cys321), but the sequence alignment showed that the corresponding residue is Ala329 in human GDH. To investigate whether Ebselen could be an inhibitor for human GDH, we cloned and expressed an N-terminal His-tagged human GDH in E. coli. The recombinant human GDH enzyme showed expected properties such as adenosine diphosphate activation and nicotinamide adenine dinucleotide/nicotinamide adenine dinucleotide phosphate dual recognition. Further, we developed a 2-(3-(2-methoxy-4-nitrophenyl)-2-(4-nitrophenyl)-2H-tetrazol-3-ium-5-yl) benzenesulfonate sodium salt (EZMTT)-based assay for human GDH, which was highly sensitive and is suitable for high-throughput screening for potent GDH inhibitors. In addition, ForteBio binding assays demonstrated that Ebselen is a reversible active site inhibitor for human GDH. Since Ebselen is a multifunctional organoselenium compound in Phase III clinical trials for inflammation, an Ebselen-based GDH inhibitor might be valuable for future drug discovery for HHS patients.

  6. An NAD+-dependent transcriptional program governs self-renewal and radiation resistance in glioblastoma.

    PubMed

    Gujar, Amit D; Le, Son; Mao, Diane D; Dadey, David Y A; Turski, Alice; Sasaki, Yo; Aum, Diane; Luo, Jingqin; Dahiya, Sonika; Yuan, Liya; Rich, Keith M; Milbrandt, Jeffrey; Hallahan, Dennis E; Yano, Hiroko; Tran, David D; Kim, Albert H

    2016-12-20

    Accumulating evidence suggests cancer cells exhibit a dependency on metabolic pathways regulated by nicotinamide adenine dinucleotide (NAD + ). Nevertheless, how the regulation of this metabolic cofactor interfaces with signal transduction networks remains poorly understood in glioblastoma. Here, we report nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting step in NAD + synthesis, is highly expressed in glioblastoma tumors and patient-derived glioblastoma stem-like cells (GSCs). High NAMPT expression in tumors correlates with decreased patient survival. Pharmacological and genetic inhibition of NAMPT decreased NAD + levels and GSC self-renewal capacity, and NAMPT knockdown inhibited the in vivo tumorigenicity of GSCs. Regulatory network analysis of RNA sequencing data using GSCs treated with NAMPT inhibitor identified transcription factor E2F2 as the center of a transcriptional hub in the NAD + -dependent network. Accordingly, we demonstrate E2F2 is required for GSC self-renewal. Downstream, E2F2 drives the transcription of members of the inhibitor of differentiation (ID) helix-loop-helix gene family. Finally, we find NAMPT mediates GSC radiation resistance. The identification of a NAMPT-E2F2-ID axis establishes a link between NAD + metabolism and a self-renewal transcriptional program in glioblastoma, with therapeutic implications for this formidable cancer.

  7. A lectin receptor kinase as a potential sensor for extracellular nicotinamide adenine dinucleotide in Arabidopsis thaliana

    PubMed Central

    Wang, Chenggang; Zhou, Mingqi; Zhang, Xudong; Yao, Jin; Zhang, Yanping; Mou, Zhonglin

    2017-01-01

    Nicotinamide adenine dinucleotide (NAD+) participates in intracellular and extracellular signaling events unrelated to metabolism. In animals, purinergic receptors are required for extracellular NAD+ (eNAD+) to evoke biological responses, indicating that eNAD+ may be sensed by cell-surface receptors. However, the identity of eNAD+-binding receptors still remains elusive. Here, we identify a lectin receptor kinase (LecRK), LecRK-I.8, as a potential eNAD+ receptor in Arabidopsis. The extracellular lectin domain of LecRK-I.8 binds NAD+ with a dissociation constant of 436.5 ± 104.8 nM, although much higher concentrations are needed to trigger in vivo responses. Mutations in LecRK-I.8 inhibit NAD+-induced immune responses, whereas overexpression of LecRK-I.8 enhances the Arabidopsis response to NAD+. Furthermore, LecRK-I.8 is required for basal resistance against bacterial pathogens, substantiating a role for eNAD+ in plant immunity. Our results demonstrate that lectin receptors can potentially function as eNAD+-binding receptors and provide direct evidence for eNAD+ being an endogenous signaling molecule in plants. DOI: http://dx.doi.org/10.7554/eLife.25474.001 PMID:28722654

  8. Neuronal death induced by misfolded prion protein is due to NAD+ depletion and can be relieved in vitro and in vivo by NAD+ replenishment

    PubMed Central

    Zhou, Minghai; Ottenberg, Gregory; Sferrazza, Gian Franco; Hubbs, Christopher; Fallahi, Mohammad; Rumbaugh, Gavin; Brantley, Alicia F.

    2015-01-01

    The mechanisms of neuronal death in protein misfolding neurodegenerative diseases such as Alzheimer’s, Parkinson’s and prion diseases are poorly understood. We used a highly toxic misfolded prion protein (TPrP) model to understand neurotoxicity induced by prion protein misfolding. We show that abnormal autophagy activation and neuronal demise is due to severe, neuron-specific, nicotinamide adenine dinucleotide (NAD+) depletion. Toxic prion protein-exposed neuronal cells exhibit dramatic reductions of intracellular NAD+ followed by decreased ATP production, and are completely rescued by treatment with NAD+ or its precursor nicotinamide because of restoration of physiological NAD+ levels. Toxic prion protein-induced NAD+ depletion results from PARP1-independent excessive protein ADP-ribosylations. In vivo, toxic prion protein-induced degeneration of hippocampal neurons is prevented dose-dependently by intracerebral injection of NAD+. Intranasal NAD+ treatment of prion-infected sick mice significantly improves activity and delays motor impairment. Our study reveals NAD+ starvation as a novel mechanism of autophagy activation and neurodegeneration induced by a misfolded amyloidogenic protein. We propose the development of NAD+ replenishment strategies for neuroprotection in prion diseases and possibly other protein misfolding neurodegenerative diseases. PMID:25678560

  9. Antidiabetic, Lipid Normalizing, and Nephroprotective Actions of the Strawberry: A Potent Supplementary Fruit

    PubMed Central

    Mandave, Pallavi; Khadke, Suresh; Karandikar, Manjiri; Pandit, Vijaya; Ranjekar, Prabhakar; Kuvalekar, Aniket; Mantri, Nitin

    2017-01-01

    The study was designed to assess the effect of different strawberry extracts on glucose levels, lipid profiles, and oxidative stress in nicotinamide-streptozotocin (NIC-STZ) induced diabetic rats. The associated changes were evaluated through biochemical, molecular, and histological assays. Diabetes was induced by intraperitoneal injection of STZ to albino Wistar rats after treatment with nicotinamide. Aqueous, hydroalcoholic, and alcoholic strawberry extracts were administrated orally to diabetic rats. Treatment of strawberry extracts improved lipid profile, liver function, and serum creatinine and led to a significant increase in antioxidant status in diabetic rats. Real-time PCR expression analysis of genes from the liver of animals treated with strawberry extracts exhibited downregulation of several fatty acid synthesis genes, transcription factors, such as Sterol regulatory Element Binding Transcription factor (SREBP) and Nuclear Factor-κβ (NF-κβ), and inflammatory markers, like Interleukin 6 (IL6) and Tumor Necrosis Factor-α (TNF-α). Strawberry extracts also upregulated liver Peroxisome Proliferator Activated Receptor-γ (PPAR-γ). Histological examination confirmed the nephroprotective and β-cell regeneration/protection effects of strawberry extracts. The present study demonstrates several beneficial effects of strawberry extracts along with its probable mechanism of action. PMID:28085064

  10. Quantitative Determination of α-Arbutin, β-Arbutin, Kojic Acid, Nicotinamide, Hydroquinone, Resorcinol, 4-Methoxyphenol, 4-Ethoxyphenol, and Ascorbic Acid from Skin Whitening Products by HPLC-UV.

    PubMed

    Wang, Yan-Hong; Avonto, Cristina; Avula, Bharathi; Wang, Mei; Rua, Diego; Khan, Ikhlas A

    2015-01-01

    An HPLC-UV method was developed for the quantitative analysis of nine skin whitening agents in a single injection. These compounds are α-arbutin, β-arbutin, kojic acid, nicotinamide, resorcinol, ascorbic acid, hydroquinone, 4-methoxyphenol, and 4-ethoxyphenol. The separation was achieved on a reversed-phase C18 column within 30 min. The mobile phase was composed of water and methanol, both containing 0.1% acetic acid (v/v). The stability of the analytes was evaluated at different pH values between 2.3 and 7.6, and the extraction procedure was validated for different types of skin whitening product matrixes, which included two creams, a soap bar, and a capsule. The best solvent system for sample preparation was 20 mM NaH2PO4 containing 10% methanol at pH 2.3. The analytical method was validated for accuracy, precision, LOD, and LOQ. The developed HPLC-UV method was applied for the quantitation of the nine analytes in 59 skin whitening products including creams, lotions, sera, foams, gels, mask sheets, soap bars, tablets, and capsules.

  11. Catabolism of phloroglucinol by the rumen anaerobe coprococcus.

    PubMed

    Patel, T R; Jure, K G; Jones, G A

    1981-12-01

    A rumen isolate, Coprococcus, sp. Pe(1)5, was found to carry phloroglucinol reductase, which catalyzed the initial step in the breakdown of phloroglucinol. The organism uses phloroglucinol as the sole source of carbon and energy when grown in the absence of oxygen. Induced levels of enzyme were detected in cells grown either on phloroglucinol or on other carbon sources in the presence of limiting quantities of phloroglucinol. Although the organism is a strict anaerobe, the enzyme from anaerobically grown cells was insensitive to air. The partially purified enzyme required reduced nicotinamide adenine dinucleotide phosphate as an electron donor and was specific for phloroglucinol. However, partial enzyme activity (14 to 17%) was also detected in the presence of 2-methyl-1,4-naphthoquinone but not in the presence of several other phenolic compounds. The enzyme exhibited a higher affinity for phloroglucinol than for reduced nicotinamide adenine dinucleotide phosphate, with K(m) values of 3.0 x 10 M and 29.0 x 10 M, respectively. The optimum pH for maximal enzyme activity was 7.4, and the molecular weight of the native protein was about 130,000, as determined by the Sephadex gel filtration technique.

  12. Catabolism of Phloroglucinol by the Rumen Anaerobe Coprococcus

    PubMed Central

    Patel, T. R.; Jure, K. G.; Jones, G. A.

    1981-01-01

    A rumen isolate, Coprococcus, sp. Pe15, was found to carry phloroglucinol reductase, which catalyzed the initial step in the breakdown of phloroglucinol. The organism uses phloroglucinol as the sole source of carbon and energy when grown in the absence of oxygen. Induced levels of enzyme were detected in cells grown either on phloroglucinol or on other carbon sources in the presence of limiting quantities of phloroglucinol. Although the organism is a strict anaerobe, the enzyme from anaerobically grown cells was insensitive to air. The partially purified enzyme required reduced nicotinamide adenine dinucleotide phosphate as an electron donor and was specific for phloroglucinol. However, partial enzyme activity (14 to 17%) was also detected in the presence of 2-methyl-1,4-naphthoquinone but not in the presence of several other phenolic compounds. The enzyme exhibited a higher affinity for phloroglucinol than for reduced nicotinamide adenine dinucleotide phosphate, with Km values of 3.0 × 10−5 M and 29.0 × 10−5 M, respectively. The optimum pH for maximal enzyme activity was 7.4, and the molecular weight of the native protein was about 130,000, as determined by the Sephadex gel filtration technique. PMID:16345897

  13. [Influence exogenous nicotinamide adenine dinucleotide (NAD+) on contractile and bioelectric activity of the rat heart].

    PubMed

    Pustovit, K B; Kuz'min, V S; Sukhova, G S

    2014-04-01

    This study is aimed to the investigation of the nicotinamide adenine dinucleotide (NAD+) effects and mechanisms of action in a heart. NAD+ (mcM) induces multiphase alternation of contractile activity of isolated rat heart: short positive inotropic action is followed by a negative inotropic phase. NAD+ (1-100 mcM) induces decreasing of action potential duration (APD) in rat atrial myocardium (from 45 +/- 0.82 ms in control experiments to 39 +/- 1.05 (n = 8) and 32 +/- 2 (n = 8) during application of 10 and 100 mcM of NAD+, respectively). Significant APD increase (from 45 +/- 0.82 ms to 74 +/- 1.89 (n = 8) ms) was observed during washing out of NAD+ (100 mcM). ATP or adenosine was unable to increase APD both during application or washing out. NAD+ induced APD decrease was not suppressed by P1-antagonist theophylline. P1-purinoreceptor and metabolite independent direct action of NAD+ in rat heart is suggested. Activation of P2X or P2Y receptors, cyclic ADP-ribose accumulation in cardiomyocytes is proposed as a main mechanism of NAD(+)-induced effects in the heart.

  14. The 2.5 Å Crystal Structure of the SIRT1 Catalytic Domain Bound to Nicotinamide Adenine Dinucleotide (NAD + ) and an Indole (EX527 Analogue) Reveals a Novel Mechanism of Histone Deacetylase Inhibition

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhao, Xun; Allison, Dagart; Condon, Bradley

    2013-02-14

    The sirtuin SIRT1 is a NAD+-dependent histone deacetylase, a Sir2 family member, and one of seven human sirtuins. Sirtuins are conserved from archaea to mammals and regulate transcription, genome stability, longevity, and metabolism. SIRT1 regulates transcription via deacetylation of transcription factors such as PPARγ, NFκB, and the tumor suppressor protein p53. EX527 (27) is a nanomolar SIRT1 inhibitor and a micromolar SIRT2 inhibitor. To elucidate the mechanism of SIRT inhibition by 27, we determined the 2.5 Å crystal structure of the SIRT1 catalytic domain (residues 241–516) bound to NAD+ and the 27 analogue compound 35. 35 binds deep in themore » catalytic cleft, displacing the NAD+ nicotinamide and forcing the cofactor into an extended conformation. The extended NAD+ conformation sterically prevents substrate binding. The SIRT1/NAD+/35 crystal structure defines a novel mechanism of histone deacetylase inhibition and provides a basis for understanding, and rationally improving, inhibition of this therapeutically important target by drug-like molecules.« less

  15. Molecular Links between Caloric Restriction and Sir2/SIRT1 Activation

    PubMed Central

    2014-01-01

    Ageing is the most significant risk factor for a range of prevalent diseases, including cancer, cardiovascular disease, and diabetes. Accordingly, interventions are needed for delaying or preventing disorders associated with the ageing process, i.e., promotion of healthy ageing. Calorie restriction is the only nongenetic and the most robust approach to slow the process of ageing in evolutionarily divergent species, ranging from yeasts, worms, and flies to mammals. Although it has been known for more than 80 years that calorie restriction increases lifespan, a mechanistic understanding of this phenomenon remains elusive. Yeast silent information regulator 2 (Sir2), the founding member of the sirtuin family of protein deacetylases, and its mammalian homologue Sir2-like protein 1 (SIRT1), have been suggested to promote survival and longevity of organisms. SIRT1 exerts protective effects against a number of age-associated disorders. Caloric restriction increases both Sir2 and SIRT1 activity. This review focuses on the mechanistic insights between caloric restriction and Sir2/SIRT1 activation. A number of molecular links, including nicotinamide adenine dinucleotide, nicotinamide, biotin, and related metabolites, are suggested to be the most important conduits mediating caloric restriction-induced Sir2/SIRT1 activation and lifespan extension. PMID:25349818

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

    NASA Astrophysics Data System (ADS)

    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.

  17. Human sperm NADH and NADPH diaphorase cytochemistry: correlation with sperm motility.

    PubMed

    Zini, A; O'Bryan, M K; Israel, L; Schlegel, P N

    1998-03-01

    We have examined the correlation between the retention of residual sperm cytoplasm and sperm motility in semen from men presenting for infertility evaluation. Semen samples (n = 12) were obtained from nonazoospermic men presenting for infertility evaluation at our institution. Samples were fractionated into high-, intermediate-, and low-density subpopulations by Percoll gradients in order to examine the correlation between the retention of residual sperm cytoplasm and sperm motility. Residual sperm cytoplasm retention was detected by cytochemical staining of sperm for nicotinamide adenine dinucleotide (NADH)- or nicotinamide adenine dinucleotide phosphate (NADPH)-dependent diaphorase activity. The different sperm subpopulations (low, intermediate, and high density) had significantly different percentages of sperm with droplet retention (analysis of variance, P < 0.05). Using either NADH or NADPH diaphorase staining as a marker of the cytoplasmic space, a significant negative correlation was observed between the percentage of sperm with residual cytoplasmic droplets and the percentage of motile sperm (r = -0.58 and -0.61, respectively, P < 0.05). Assessment of residual sperm cytoplasm retention is a simple diagnostic test. Although this test is of unproven value in the management of infertile men, this and other studies suggest that it may provide useful data on sperm function.

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

    PubMed

    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.

  19. Targeting MUC1 mediated tumor stromal metabolic interaction in Triple negative Breast Cancer

    DTIC Science & Technology

    2016-11-01

    biosynthesis, D- Glutamine and D-glutamate metabolism, Nicotinate and nicotinamide metabolism, and Nitrogen metabolism were amongst the redundant...pathways identified in MDA- MB-468 (Fig 3). Nitrogen metabolism and D- Glutamine and D-glutamate metabolism pathways were filtered out as potential...Figure 4. MUC1 alters TNBC metabolism. Representation of (A) D- Glutamine and D- glutamate metabolism and (B

  20. Targeting MUC1-Mediated Tumor-Stromal Metabolic Interaction in Triple-Negative Breast Cancer

    DTIC Science & Technology

    2016-11-01

    biosynthesis, D- Glutamine and D-glutamate metabolism, Nicotinate and nicotinamide metabolism, and Nitrogen metabolism were amongst the redundant...pathways identified in MDA- MB-468 (Fig 3). Nitrogen metabolism and D- Glutamine and D-glutamate metabolism pathways were filtered out as potential...Figure 4. MUC1 alters TNBC metabolism. Representation of (A) D- Glutamine and D- glutamate metabolism and (B

  1. Death by Protein Damage in Irradiated Cells

    DTIC Science & Technology

    2011-01-01

    tardigrades, J. Exp. Biol. 212 (2009) 4033– 4039. [63] A. Oren, N. Gunde-Cimerman, Mycosporines and mycosporine - like amino acids : UV protectants or...catalytically remove superoxide via a disproportionation mechanism [29,46]; and amino acids and peptides, which scav- enge hydroxyl radicals very efficiently...most radiation resistant mutants of B. pumilus displayed mul- tiple amino acid auxotrophies and a requirement for nicotinamide adenine dinucleotide

  2. The Tail Wagging the Dog: Insights into Catalysis in R67 Dihydrofolate Reductase

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kamath, Ganesh K; Agarwal, Pratul K

    2010-01-01

    Plasmid-encoded R67 dihydrofolate reductase (DHFR) catalyzes a hydride transfer reaction between substrate dihydrofolate (DHF) and its cofactor, nicotinamide adenine dinucleotide phosphate (NADPH). R67 DHFR is a homotetramer that exhibits numerous characteristics of a primitive enzyme, including promiscuity in binding of substrate and cofactor, formation of nonproductive complexes, and the absence of a conserved acid in its active site. Furthermore, R67's active site is a pore, which is mostly accessible by bulk solvent. This study uses a computational approach to characterize the mechanism of hydride transfer. Not surprisingly, NADPH remains fixed in one-half of the active site pore using numerous interactionsmore » with R67. Also, stacking between the nicotinamide ring of the cofactor and the pteridine ring of the substrate, DHF, at the hourglass center of the pore, holds the reactants in place. However, large movements of the p-aminobenzoylglutamate tail of DHF occur in the other half of the pore because of ion pair switching between symmetry-related K32 residues from two subunits. This computational result is supported by experimental results that the loss of these ion pair interactions (located >13 {angstrom} from the center of the pore) by addition of salt or in asymmetric K32M mutants leads to altered enzyme kinetics [Hicks, S. N., et al. (2003) Biochemistry 42, 10569-10578; Hicks, S. N., et al. (2004) J. Biol. Chem. 279, 46995?47002]. The tail movement at the edge of the active site, coupled with the fixed position of the pteridine ring in the center of the pore, leads to puckering of the pteridine ring and promotes formation of the transition state. Flexibility coupled to R67 function is unusual as it contrasts with the paradigm that enzymes use increased rigidity to facilitate attainment of their transition states. A comparison with chromosomal DHFR indicates a number of similarities, including puckering of the nicotinamide ring and changes in the DHF tail angle, accomplished by different elements of the dissimilar protein folds.« less

  3. Two new compounds from the aerial parts of Bergenia himalaica Boriss and their anti-hyperglycemic effect in streptozotocin-nicotinamide induced diabetic rats.

    PubMed

    Siddiqui, Bina S; Hasan, Mashooda; Mairaj, Farah; Mehmood, Iffat; Hafizur, Rahman Md; Hameed, Abdul; Khan Shinwari, Zabta

    2014-03-28

    Bergenia himalaica Boriss is mainly distributed in the temperate Himalayas between altitudes of 900 and 3000m ranging from the southeastern regions in central Asia and northern regions in South Asia. The plant has a long history of its use in traditional medicine for the treatment of various diseases such as diabetes, urinary complaints, kidney stones, hemorrhagic diseases and epilepsy. The aim of this study is to isolate pure compounds from Bergenia himalaica Boriss, elucidate their structures and determine their blood glucose lowering activity to obtain additional scientific evidence for its usage in traditional medicine for the management of diabetes. The crude methanolic extract from the aerial parts of Bergenia himalaica Boriss was separated into EtOAc and water sub-extracts and the EtOAc sub-extract was further divided into petroleum ether soluble and insoluble fractions. The pet-ether insoluble fraction was subjected to fractionation through column chromatography followed by prep. TLC. The blood glucose lowering activity of the 2 new compounds was evaluated in streptozotocin-nicotinamide induced diabetic rats. Additionally, glucose-stimulated insulin secretion was measured on isolated mice islets. Two new compounds bergenicin and bergelin were isolated and their structures determined on the basis of spectral analysis. Significant decrease of blood glucose was observed at 1-h (1.0mg/kg) and 2-h (0.5mg/kg), after bergenicin administration to the diabetic rats and at 2-h (1.0mg/kg) and 3-h (0.5mg/kg), after bergelin administration. Bergenicin, but not bergelin, enhanced glucose-stimulated insulin secretion in isolated pancreatic islets. In the present studies two new compounds, bergenicin and bergelin were isolated from Bergenia himalaica Boriss and their structures were elucidated. Both the compounds showed anti-hyperglycemic effects in streptozotocin-nicotinamide induced diabetic rats. Bergenicin showed insulinotropic effect; suggesting that the anti-hyperglycemic effect is mostly due to enhancement of insulin secretion from pancreatic β-cells. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  4. Nicotinamide riboside restores cognition through an upregulation of proliferator-activated receptor-γ coactivator 1α regulated β-secretase 1 degradation and mitochondrial gene expression in Alzheimer’s mouse models

    PubMed Central

    Gong, Bing; Pan, Yong; Vempati, Prashant; Zhao, Wei; Knable, Lindsay; Ho, Lap; Wang, Jun; Sastre, Magdalena; Ono, Kenjiro; Sauve, Anthony A.; Pasinetti, Giulio M.

    2013-01-01

    Nicotinamide adenine dinucleotide (NAD)+, a coenzyme involved in redox activities in the mitochondrial electron transport chain, has been identified as a key regulator of the lifespan-extending effects, and the activation of NAD+ expression has been linked with a decrease in beta-amyloid (Aβ) toxicity in Alzheimer’s disease (AD). Nicotinamide riboside (NR) is a NAD+ precursor, it promotes peroxisome proliferator-activated receptor-γ coactivator 1 (PGC)-1α expression in the brain. Evidence has shown that PGC-1α is a crucial regulator of Aβ generation because it affects β-secretase (BACE1) degradation. In this study we tested the hypothesis that NR treatment in an AD mouse model could attenuate Aβ toxicity through the activation of PGC-1α-mediated BACE1 degradation. Using the Tg2576 AD mouse model, using in vivo behavioral analyses, biochemistry assays, small hairpin RNA (shRNA) gene silencing and electrophysiological recording, we found (1) dietary treatment of Tg2576 mice with 250 mg/kg/day of NR for 3 months significantly attenuates cognitive deterioration in Tg2576 mice and coincides with an increase in the steady-state levels of NAD+ in the cerebral cortex; (2) application of NR to hippocampal slices (10 µM) for 4 hours abolishes the deficits in long-term potentiation recorded in the CA1 region of Tg2576 mice; (3) NR treatment promotes PGC-1α expression in the brain coinciding with enhanced degradation of BACE1 and the reduction of Aβ production in Tg2576 mice. Further in vitro studies confirmed that BACE1 protein content is decreased by NR treatment in primary neuronal cultures derived from Tg2576 embryos, in which BACE1 degradation was prevented by PGC-1α-shRNA gene silencing; and (4) NR treatment and PGC-1α overexpression enhance BACE1 ubiquitination and proteasomal degradation. Our studies suggest that dietary treatment with NR might benefit AD cognitive function and synaptic plasticity, inpart by promoting PGC-1α-mediated BACE1 ubiquitination and degradation, thus preventing Aβ production in the brain. PMID:23312803

  5. Emodin suppresses silica-induced lung fibrosis by promoting Sirt1 signaling via direct contact.

    PubMed

    Yang, Tian; Wang, Jinyuan; Pang, Yamei; Dang, Xiaomin; Ren, Hui; Liu, Ya; Chen, Mingwei; Shang, Dong

    2016-11-01

    Pulmonary silicosis is characterized by lung fibrosis, which leads to impairment of pulmonary function; the specific mechanism remains to be fully elucidated Emodin shows antifibrotic effects in several organs with fibrosis, however, it has not been investigated in pulmonary silicosis. In the present study, the possible mechanism of lung fibrosis and the antifibrotic effect of emodin in silica inhalation‑induced lung fibrosis were investigated. Pulmonary silica particle inhalation was used to induce lung fibrosis in mice. Emodin and or the sirtuin 1 (Sirt1) inhibitor, nicotinamide, were used to treat the modeled animals. Pulmonary function was assessed using an occlusion method. The deposition of collagen I and α‑smooth muscle actin (SMA) in the lung tissue were detected using fluorescence staining; transforming growth factor‑β1 (TGF‑β1) in the bronchoalveolar lavage fluid (BALF) was examined using an enzyme‑linked immunosorbent assay; TGF-β1/Sirt1/small mothers against decapentaplegic (Smad) signaling activation in lung tissue was also examined. The molecular contacts between emodin were evaluated using liquid chromatography‑mass spectrometry analysis. The deposition of collagen I and α‑SMA in lung tissues were found to be elevated following silica exposure, however, this was relieved by emodin treatment. The pulmonary function of the animals was impaired by silica inhalation, and this was improved by emodin administration. However, the therapeutic effects of emodin on lung fibrosis were impaired by nicotinamide administration. The levels of TGF‑β1 in the BALF and lung tissue were elevated by silica inhalation, however, they were not affected by either emodin or nicotinamide treatment. Additionally, emodin was found to increase the expression level of Sirt1, which decreased the level of deacetylated Smad3 to attenuate collagen deposition. Furthermore, the data suggested that there was direct binding between emodin and Sirt1. Sirt1‑regulated TGF‑β1/Smad signaling was involved in silica inhalation‑induced lung fibrosis. Emodin attenuated this lung fibrosis to improve pulmonary function by targeting Sirt1, which regulated TGF-β1/Smad fibrotic signaling.

  6. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schuster, Susanne, E-mail: Susanne.Schuster@medizin.uni-leipzig.de; Penke, Melanie; Gorski, Theresa

    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 complex1more » (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 AMPKα and downregulates mTOR signaling. • NMN abrogates the effects of FK866-induced NAMPT inhibition. • Non-cancerous human hepatocytes are less sensitive to FK866.« less

  7. Inhibition of Nicotinamide Phosphoribosyltransferase (NAMPT), an Enzyme Essential for NAD+ Biosynthesis, Leads to Altered Carbohydrate Metabolism in Cancer Cells*

    PubMed Central

    Tan, Bo; Dong, Sucai; Shepard, Robert L.; Kays, Lisa; Roth, Kenneth D.; Geeganage, Sandaruwan; Kuo, Ming-Shang; Zhao, Genshi

    2015-01-01

    Nicotinamide phosphoribosyltransferase (NAMPT) has been extensively studied due to its essential role in NAD+ biosynthesis in cancer cells and the prospect of developing novel therapeutics. To understand how NAMPT regulates cellular metabolism, we have shown that the treatment with FK866, a specific NAMPT inhibitor, leads to attenuation of glycolysis by blocking the glyceraldehyde 3-phosphate dehydrogenase step (Tan, B., Young, D. A., Lu, Z. H., Wang, T., Meier, T. I., Shepard, R. L., Roth, K., Zhai, Y., Huss, K., Kuo, M. S., Gillig, J., Parthasarathy, S., Burkholder, T. P., Smith, M. C., Geeganage, S., and Zhao, G. (2013) Pharmacological inhibition of nicotinamide phosphoribosyltransferase (NAMPT), an enzyme essential for NAD+ biosynthesis, in human cancer cells: metabolic basis and potential clinical implications. J. Biol. Chem. 288, 3500–3511). Due to technical limitations, we failed to separate isotopomers of phosphorylated sugars. In this study, we developed an enabling LC-MS methodology. Using this, we confirmed the previous findings and also showed that NAMPT inhibition led to accumulation of fructose 1-phosphate and sedoheptulose 1-phosphate but not glucose 6-phosphate, fructose 6-phosphate, and sedoheptulose 7-phosphate as previously thought. To investigate the metabolic basis of the metabolite formation, we carried out biochemical and cellular studies and established the following. First, glucose-labeling studies indicated that fructose 1-phosphate was derived from dihydroxyacetone phosphate and glyceraldehyde, and sedoheptulose 1-phosphate was derived from dihydroxyacetone phosphate and erythrose via an aldolase reaction. Second, biochemical studies showed that aldolase indeed catalyzed these reactions. Third, glyceraldehyde- and erythrose-labeling studies showed increased incorporation of corresponding labels into fructose 1-phosphate and sedoheptulose 1-phosphate in FK866-treated cells. Fourth, NAMPT inhibition led to increased glyceraldehyde and erythrose levels in the cell. Finally, glucose-labeling studies showed accumulated fructose 1,6-bisphosphate in FK866-treated cells mainly derived from dihydroxyacetone phosphate and glyceraldehyde 3-phosphate. Taken together, this study shows that NAMPT inhibition leads to attenuation of glycolysis, resulting in further perturbation of carbohydrate metabolism in cancer cells. The potential clinical implications of these findings are also discussed. PMID:25944913

  8. Metabolic Profiling of Geobacter sulfurreducens during Industrial Bioprocess Scale-Up.

    PubMed

    Muhamadali, Howbeer; Xu, Yun; Ellis, David I; Allwood, J William; Rattray, Nicholas J W; Correa, Elon; Alrabiah, Haitham; Lloyd, Jonathan R; Goodacre, Royston

    2015-05-15

    During the industrial scale-up of bioprocesses it is important to establish that the biological system has not changed significantly when moving from small laboratory-scale shake flasks or culturing bottles to an industrially relevant production level. Therefore, during upscaling of biomass production for a range of metal transformations, including the production of biogenic magnetite nanoparticles by Geobacter sulfurreducens, from 100-ml bench-scale to 5-liter fermentors, we applied Fourier transform infrared (FTIR) spectroscopy as a metabolic fingerprinting approach followed by the analysis of bacterial cell extracts by gas chromatography-mass spectrometry (GC-MS) for metabolic profiling. FTIR results clearly differentiated between the phenotypic changes associated with different growth phases as well as the two culturing conditions. Furthermore, the clustering patterns displayed by multivariate analysis were in agreement with the turbidimetric measurements, which displayed an extended lag phase for cells grown in a 5-liter bioreactor (24 h) compared to those grown in 100-ml serum bottles (6 h). GC-MS analysis of the cell extracts demonstrated an overall accumulation of fumarate during the lag phase under both culturing conditions, coinciding with the detected concentrations of oxaloacetate, pyruvate, nicotinamide, and glycerol-3-phosphate being at their lowest levels compared to other growth phases. These metabolites were overlaid onto a metabolic network of G. sulfurreducens, and taking into account the levels of these metabolites throughout the fermentation process, the limited availability of oxaloacetate and nicotinamide would seem to be the main metabolic bottleneck resulting from this scale-up process. Additional metabolite-feeding experiments were carried out to validate the above hypothesis. Nicotinamide supplementation (1 mM) did not display any significant effects on the lag phase of G. sulfurreducens cells grown in the 100-ml serum bottles. However, it significantly improved the growth behavior of cells grown in the 5-liter bioreactor by reducing the lag phase from 24 h to 6 h, while providing higher yield than in the 100-ml serum bottles. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  9. Emodin suppresses silica-induced lung fibrosis by promoting Sirt1 signaling via direct contact

    PubMed Central

    Yang, Tian; Wang, Jinyuan; Pang, Yamei; Dang, Xiaomin; Ren, Hui; Liu, Ya; Chen, Mingwei; Shang, Dong

    2016-01-01

    Pulmonary silicosis is characterized by lung fibrosis, which leads to impairment of pulmonary function; the specific mechanism remains to be fully elucidated Emodin shows antifibrotic effects in several organs with fibrosis, however, it has not been investigated in pulmonary silicosis. In the present study, the possible mechanism of lung fibrosis and the antifibrotic effect of emodin in silica inhalation-induced lung fibrosis were investigated. Pulmonary silica particle inhalation was used to induce lung fibrosis in mice. Emodin and or the sirtuin 1 (Sirt1) inhibitor, nicotinamide, were used to treat the modeled animals. Pulmonary function was assessed using an occlusion method. The deposition of collagen I and α-smooth muscle actin (SMA) in the lung tissue were detected using fluorescence staining; transforming growth factor-β1 (TGF-β1) in the bronchoalveolar lavage fluid (BALF) was examined using an enzyme-linked immunosorbent assay; TGF-β1/Sirt1/small mothers against decapentaplegic (Smad) signaling activation in lung tissue was also examined. The molecular contacts between emodin were evaluated using liquid chromatography-mass spectrometry analysis. The deposition of collagen I and α-SMA in lung tissues were found to be elevated following silica exposure, however, this was relieved by emodin treatment. The pulmonary function of the animals was impaired by silica inhalation, and this was improved by emodin administration. However, the therapeutic effects of emodin on lung fibrosis were impaired by nicotinamide administration. The levels of TGF-β1 in the BALF and lung tissue were elevated by silica inhalation, however, they were not affected by either emodin or nicotinamide treatment. Additionally, emodin was found to increase the expression level of Sirt1, which decreased the level of deacetylated Smad3 to attenuate collagen deposition. Furthermore, the data suggested that there was direct binding between emodin and Sirt1. Sirt1-regulated TGF-β1/Smad signaling was involved in silica inhalation-induced lung fibrosis. Emodin attenuated this lung fibrosis to improve pulmonary function by targeting Sirt1, which regulated TGF-β1/Smad fibrotic signaling. PMID:27748907

  10. STUDIES ON MAMMALIAN AND HUMAN PYRUVATE AND ALPHA-KETOGLUTARATE DEHYDROGENATION COMPLEXES.

    DTIC Science & Technology

    Enzyme systems that catalyze a coenzyme A- and nicotinamide adenine dinucleotide-linked oxidative decarboxylation of pyruvate and alpha - ketoglutarate ...The pig heart pyruvate dehydrogenase complex was strongly inhibited by EDTA at low concentration, but the pig heart alpha - ketoglutarate ...On the oxidative decarboxylation of alpha -keto acids in pig heart complexes, Ca(2+) was strongly stimulatory to the same or more extent than Mg(2

  11. Nutrition and the brain.

    PubMed

    Morley, John E

    2010-02-01

    Severe nutritional deficiencies, such as protein energy malnutrition and deficiency of nicotinamide, vitamin B(12), folate, and thiamine, have long been recognized to cause severe confusion. Lesser vitamin deficiencies have been linked to the pathogenesis of delirium. Hypo- and hyperglycemia and hypertriglyceridemia can cause cognitive deficits. Epidemiologic and animal studies have linked several other nutrients (omega-3 fatty acids, lutein, alpha-lipoic acid, and the Mediterranean diet) to cognitive performance and the prevention of dementia.

  12. ROS open roads to roundworm infection.

    PubMed

    Feng, Baomin; Shan, Libo

    2014-04-08

    The rapid production of reactive oxygen species (ROS) upon pathogen attack is generally considered a defense mechanism for microbial killing and an initiation of host defense responses in plants and animals. In this issue, Siddique et al. show that nicotinamide adenine dinucleotide phosphate oxidase-derived ROS function as a pathogenicity factor to promote the roundworm nematode infection in Arabidopsis thaliana, revealing the complex action of ROS in host-pathogen interactions.

  13. Restoring NAD(+) Levels with NAD(+) Intermediates, the Second Law of Thermodynamics and Aging Delay.

    PubMed

    Poljsak, Borut; Milisav, Irina

    2018-04-26

    The hypothesis regarding the role of increased nicotinamide adenine dinucleotide (NAD+) levels with reference to the fundamental concepts of ageing and entropy is presented. Considering the second law of thermodynamics, NAD+ seems the appropriate candidate for reversing many aging-associated pathologies. NAD+ is presented as an essential compound that enables organisms to stay highly organized and well-maintained, with a lower entropy state.

  14. Roles of Nicotinamide Adenine Dinucleotide Phosphate (NADPH) Oxidase in Angiogenesis: Isoform-Specific Effects

    PubMed Central

    Wang, Haibo; Hartnett, M. Elizabeth

    2017-01-01

    Angiogenesis is the formation of new blood vessels from preexisting ones and is implicated in physiologic vascular development, pathologic blood vessel growth, and vascular restoration. This is in contrast to vasculogenesis, which is de novo growth of vessels from vascular precursors, or from vascular repair that occurs when circulating endothelial progenitor cells home into an area and develop into blood vessels. The objective of this review is to discuss the isoform-specific role of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) in physiologic and pathologic angiogenesis and vascular repair, but will not specifically address vasculogenesis. As the major source of reactive oxygen species (ROS) in vascular endothelial cells (ECs), NOX has gained increasing attention in angiogenesis. Activation of NOX leads to events necessary for physiologic and pathologic angiogenesis, including EC migration, proliferation and tube formation. However, activation of different NOX isoforms has different effects in angiogenesis. Activation of NOX2 promotes pathologic angiogenesis and vascular inflammation, but may be beneficial in revascularization in the hindlimb ischemic model. In contrast, activation of NOX4 appears to promote physiologic angiogenesis mainly by protecting the vasculature during ischemia, hypoxia and inflammation and by restoring vascularization, except in models of oxygen-induced retinopathy and diabetes where NOX4 activation leads to pathologic angiogenesis. PMID:28587189

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

    NASA Astrophysics Data System (ADS)

    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.

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

    PubMed

    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.

  17. Ethanol and liver: Recent insights into the mechanisms of ethanol-induced fatty liver

    PubMed Central

    Liu, Jinyao

    2014-01-01

    Alcoholic fatty liver disease (AFLD), a potentially pathologic condition, can progress to steatohepatitis, fibrosis, and cirrhosis, leading to an increased probability of hepatic failure and death. Alcohol induces fatty liver by increasing the ratio of reduced form of nicotinamide adenine dinucleotide to oxidized form of nicotinamide adenine dinucleotide in hepatocytes; increasing hepatic sterol regulatory element-binding protein (SREBP)-1, plasminogen activator inhibitor (PAI)-1, and early growth response-1 activity; and decreasing hepatic peroxisome proliferator-activated receptor-α activity. Alcohol activates the innate immune system and induces an imbalance of the immune response, which is followed by activated Kupffer cell-derived tumor necrosis factor (TNF)-α overproduction, which is in turn responsible for the changes in the hepatic SREBP-1 and PAI-1 activity. Alcohol abuse promotes the migration of bone marrow-derived cells (BMDCs) to the liver and then reprograms TNF-α expression from BMDCs. Chronic alcohol intake triggers the sympathetic hyperactivity-activated hepatic stellate cell (HSC) feedback loop that in turn activates the HSCs, resulting in HSC-derived TNF-α overproduction. Carvedilol may block this feedback loop by suppressing sympathetic activity, which attenuates the progression of AFLD. Clinical studies evaluating combination therapy of carvedilol with a TNF-α inhibitor to treat patients with AFLD are warranted to prevent the development of alcoholic liver disease. PMID:25356030

  18. Antihyperglycemic activity of Albizzia lebbeck bark extract in streptozotocin-nicotinamide induced type II diabetes mellitus rats.

    PubMed

    Patel, Priyank A; Parikh, Mihir P; Johari, Sarika; Gandhi, Tejal R

    2015-01-01

    Albizzia lebbeck (L.) Benth. (Family - Leguminosae) extract is a proven mast cell stabilizing agent. Mast cells are involved in the inflammatory processes leading to the diabetes mellitus. To evaluate the effect of A. lebbeck against experimentally induced type 2 diabetes mellitus in rats. Female Sprague-Dawley rats were randomly allocated to six groups (n = 6). Diabetes was induced by single intraperitoneal injection of streptozotocin (50 mg/kg) given after 15 min of nicotinamide administration (110 mg/kg). Treatment with methanolic extract of A. lebbeck bark (MEAL) and metformin drug as standard was given for 21 days. Serum glucose (GLU) levels were measured on the 0 day and on 1(st), 7(th), 14(th) and 21(st) day after diabetes induction. After completion of study period, various biochemical parameters in serum such as - GLU, lipid profile, urea and creatinine were estimated. One-way analysis of variance followed with post-hoc Dunnett's test was used to analyse the data. Statistical significance for the values was set at P< 0.05. MEAL significantly decreased the level of serum GLU, creatinine, urea, cholesterol, triglycerides, low-density lipoprotein-cholesterol, very low-density lipoprotein-cholesterol and increased high-density lipoprotein levels. A. lebbeck bark extract showed antihyperglycaemic activity along with antihyperlipidemic effect.

  19. Singlet Oxygen Generation by UVA Light Exposure of Endogenous Photosensitizers

    PubMed Central

    Baier, Jürgen; Maisch, Tim; Maier, Max; Engel, Eva; Landthaler, Michael; Bäumler, Wolfgang

    2006-01-01

    UVA light (320–400 nm) has been shown to produce deleterious biological effects in tissue due to the generation of singlet oxygen by substances like flavins or urocanic acid. Riboflavin, flavin mononucleotide (FMN), flavin adenine dinucleotide (FAD), β-nicotinamide adenine dinucleotide (NAD), and β-nicotinamide adenine dinucleotide phosphate (NADP), urocanic acid, or cholesterol in solution were excited at 355 nm. Singlet oxygen was directly detected by time-resolved measurement of its luminescence at 1270 nm. NAD, NADP, and cholesterol showed no luminescence signal possibly due to the very low absorption coefficient at 355 nm. Singlet oxygen luminescence of urocanic acid was clearly detected but the signal was too weak to quantify a quantum yield. The quantum yield of singlet oxygen was precisely determined for riboflavin (ΦΔ = 0.54 ± 0.07), FMN (ΦΔ = 0.51 ± 0.07), and FAD (ΦΔ = 0.07 ± 0.02). In aerated solution, riboflavin and FMN generate more singlet oxygen than exogenous photosensitizers such as Photofrin, which are applied in photodynamic therapy to kill cancer cells. With decreasing oxygen concentration, the quantum yield of singlet oxygen generation decreased, which must be considered when assessing the role of singlet oxygen at low oxygen concentrations (inside tissue). PMID:16751234

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

    PubMed Central

    Sugiyama, Kou-ichi

    2011-01-01

    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 promoted the activities of glyceraldehyde-3-phosephate dehydrogenase (G-3-PD), nicotinamide adenine dinucleotide-specific isocitrate dehydrogenase (NAD-ICDH), succinate dehydrogenase (SDH) and cytochrome-c oxidase (Cyt-c OD) in seedlings. Moreover, 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. PMID:21900743

  1. Loss of the RNA polymerase III repressor MAF1 confers obesity resistance

    PubMed Central

    Bonhoure, Nicolas; Byrnes, Ashlee; Moir, Robyn D.; Hodroj, Wassim; Preitner, Frédéric; Praz, Viviane; Marcelin, Genevieve; Chua, Streamson C.; Martinez-Lopez, Nuria; Singh, Rajat; Moullan, Norman; Auwerx, Johan; Willemin, Gilles; Shah, Hardik; Hartil, Kirsten; Vaitheesvaran, Bhavapriya; Kurland, Irwin

    2015-01-01

    MAF1 is a global repressor of RNA polymerase III transcription that regulates the expression of highly abundant noncoding RNAs in response to nutrient availability and cellular stress. Thus, MAF1 function is thought to be important for metabolic economy. Here we show that a whole-body knockout of Maf1 in mice confers resistance to diet-induced obesity and nonalcoholic fatty liver disease by reducing food intake and increasing metabolic inefficiency. Energy expenditure in Maf1−/− mice is increased by several mechanisms. Precursor tRNA synthesis was increased in multiple tissues without significant effects on mature tRNA levels, implying increased turnover in a futile tRNA cycle. Elevated futile cycling of hepatic lipids was also observed. Metabolite profiling of the liver and skeletal muscle revealed elevated levels of many amino acids and spermidine, which links the induction of autophagy in Maf1−/− mice with their extended life span. The increase in spermidine was accompanied by reduced levels of nicotinamide N-methyltransferase, which promotes polyamine synthesis, enables nicotinamide salvage to regenerate NAD+, and is associated with obesity resistance. Consistent with this, NAD+ levels were increased in muscle. The importance of MAF1 for metabolic economy reveals the potential for MAF1 modulators to protect against obesity and its harmful consequences. PMID:25934505

  2. Mitochondrial respiratory complex I probed by delayed luminescence spectroscopy

    NASA Astrophysics Data System (ADS)

    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.

  3. QSAR analysis of nicotinamidic compounds and design of potential Bruton's tyrosine kinase (Btk) inhibitors.

    PubMed

    Santos-Garcia, Letícia; Assis, Letícia C; Silva, Daniela R; Ramalho, Teodorico C; da Cunha, Elaine F F

    2016-07-01

    Bruton's tyrosine kinase (Btk) is an important enzyme in B-lymphocyte development and differentiation. Furthermore, Btk expression is considered essential for the proliferation and survival of these cells. Btk inhibition has become an attractive strategy for treating autoimmune diseases, B-cell leukemia, and lymphomas. With the objective of proposing new candidates for Btk inhibitors, we applied receptor-dependent four-dimensional quantitative structure-activity relationship (QSAR) methodology to a series of 96 nicotinamide analogs useful as Btk modulators. The QSAR models were developed using 71 compounds, the training set, and externally validated using 25 compounds, the test set. The conformations obtained by molecular dynamics simulation were overlapped in a virtual three-dimensional cubic box comprised of 2 and 5 Å cells, according to the six trial alignments. The models were generated by combining genetic function approximation and partial least squares regression technique. The analyses suggest that Model 1a yields the best results. The best equation shows [Formula: see text], r(2) = .743, RMSEC = .831, RMSECV = .879. Given the importance of the Tyr551, this residue could become a strategic target for the design of novel Btk inhibitors with improved potency. In addition, the good potency predicted for the proposed M2 compound indicates this compound as a potential Btk inhibitor candidate.

  4. In vivo native fluorescence spectroscopy and nicotinamide adinine dinucleotide/flavin adenine dinucleotide reduction and oxidation states of oral submucous fibrosis for chemopreventive drug monitoring

    NASA Astrophysics Data System (ADS)

    Sivabalan, Shanmugam; Vedeswari, C. Ponranjini; Jayachandran, Sadaksharam; Koteeswaran, Dornadula; Pravda, Chidambaranathan; Aruna, Prakasa Rao; Ganesan, Singaravelu

    2010-01-01

    Native fluorescence spectroscopy has shown potential to characterize and diagnose oral malignancy. We aim at extending the native fluorescence spectroscopy technique to characterize normal and oral submucous fibrosis (OSF) patients under pre- and post-treated conditions, and verify whether this method could also be considered in the monitoring of therapeutic prognosis noninvasively. In this study, 28 normal subjects and 28 clinically proven cases of OSF in the age group of 20 to 40 years are diagnosed using native fluorescence spectroscopy. The OSF patients are given dexamethasone sodium phosphate and hyaluronidase twice a week for 6 weeks, and the therapeutic response is monitored using fluorescence spectroscopy. The fluorescence emission spectra of normal and OSF cases of both pre- and post-treated conditions are recorded in the wavelength region of 350 to 600 nm at an excitation wavelength of 330 nm. The statistical significance is verified using discriminant analysis. The oxidation-reduction ratio of the tissue is also calculated using the fluorescence emission intensities of flavin adenine dinucleotide and nicotinamide adinine dinucleotide at 530 and 440 nm, respectively, and they are compared with conventional physical clinical examinations. This study suggests that native fluorescence spectroscopy could also be extended to OSF diagnosis and therapeutic prognosis.

  5. An investigation of indomethacin-nicotinamide cocrystal formation induced by thermal stress in the solid or liquid state.

    PubMed

    Lin, Hong-Liang; Zhang, Gang-Chun; Huang, Yu-Ting; Lin, Shan-Yang

    2014-08-01

    The impact of thermal stress on indomethacin (IMC)-nicotinamide (NIC) cocrystal formation with or without neat cogrinding was investigated using differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) microspectroscopy, and simultaneous DSC-FTIR microspectroscopy in the solid or liquid state. Different evaporation methods for preparing IMC-NIC cocrystals were also compared. The results indicated that even after cogrinding for 40 min, the FTIR spectra for all IMC-NIC ground mixtures were superimposable on the FTIR spectra of IMC and NIC components, suggesting there was no cocrystal formation between IMC and NIC after cogrinding. However, these IMC-NIC ground mixtures appear to easily undergo cocrystal formation after the application of DSC determination. Under thermal stress induced by DSC, the amount of cocrystal formation increased with increasing cogrinding time. Moreover, simultaneous DSC-FTIR microspectroscopy was a useful one-step technique to induce and clarify the thermal-induced stepwise mechanism of IMC-NIC cocrystal formation from the ground mixture in real time. Different solvent evaporation rates induced by thermal stress significantly influenced IMC-NIC cocrystal formation in the liquid state. In particular, microwave heating may promote IMC-NIC cocrystal formation in a short time. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  6. [Synthesis, characterization and antitumor activity of 5-fluorouracil-nicotinamide cocrystal].

    PubMed

    Min, W U; Xingang, Liu; Yu, Xue; Qi, Chen; Xiurong, H U; Jun, Zhou; Guping, Tang

    2017-03-25

    Objective: To synthesize 5-fluorouracil-nicotinamide (5-FU-NCT) cocrystal and to investigate its physicochemical and biological properties. Methods: The cocrystal of 5-Fu-NCT was prepared through the cooling technology. PXRD, NMR, FTIR and DSC were used to characterize the structure of 5-FU-NCT cocrystal. Solubility was measured by HPLC method. Drug resistant human liver cancer BEL-7402/5-FU cells were treated with 5-FU-NCT cocrystal, the inhibition effect was tested by MTT and HE staining, and cancer cell migration was determined by scratch test. Results: According to PXRD, NMR, FTIR and DSC results, the cocrystal of 5-Fu-NCT had been synthesized successfully. The characteristic diffraction peaks (2θ/°) of the cocrystal were 16.4, 20.4, 22.3, 27.9 and 30.1. The solubility of 5-FU-NCT was 13.5 g/L as measured by HPLC. The antitumor activity tests showed that 5-FU-NCT cocrystal enhanced anticancer effect of 5-FU, and the IC50 of 5-FU and 5-FU-NCT was 129.6 μg/mL and 42.6 μg/mL, respectively. Conclusion: 5-Fu-NCT cocrystal have been synthesized successfully through the cooling technology and it shows an enhanced anticancer effect in comparison to 5-FU on BEL-7402/5-FU cells.

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

    PubMed

    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.

  8. Budding Yeast Silencing Complexes and Regulation of Sir2 Activity by Protein-Protein Interactions

    PubMed Central

    Tanny, Jason C.; Kirkpatrick, Donald S.; Gerber, Scott A.; Gygi, Steven P.; Moazed, Danesh

    2004-01-01

    Gene silencing in the budding yeast Saccharomyces cerevisiae requires the enzymatic activity of the Sir2 protein, a highly conserved NAD-dependent deacetylase. In order to study the activity of native Sir2, we purified and characterized two budding yeast Sir2 complexes: the Sir2/Sir4 complex, which mediates silencing at mating-type loci and at telomeres, and the RENT complex, which mediates silencing at the ribosomal DNA repeats. Analyses of the protein compositions of these complexes confirmed previously described interactions. We show that the assembly of Sir2 into native silencing complexes does not alter its selectivity for acetylated substrates, nor does it allow the deacetylation of nucleosomal histones. The inability of Sir2 complexes to deacetylate nucleosomes suggests that additional factors influence Sir2 activity in vivo. In contrast, Sir2 complexes show significant enhancement in their affinities for acetylated substrates and their sensitivities to the physiological inhibitor nicotinamide relative to recombinant Sir2. Reconstitution experiments showed that, for the Sir2/Sir4 complex, these differences stem from the physical interaction of Sir2 with Sir4. Finally, we provide evidence that the different nicotinamide sensitivities of Sir2/Sir4 and RENT in vitro could contribute to locus-specific differences in how Sir2 activity is regulated in vivo. PMID:15282295

  9. Effects of Nicotinamide Adenine Dinucleotide (NAD(+)) and Diadenosine Tetraphosphate (Ap4A) on Electrical Activity of Working and Pacemaker Atrial Myocardium in Guinea Pigs.

    PubMed

    Pustovit, K B; Abramochkin, D V

    2016-04-01

    Effects of nucleotide polyphosphate compounds (nicotinamide adenine dinucleotide, NAD(+); diadenosine tetraphosphate, Ap4A) on the confi guration of action potentials were studied in isolated preparations of guinea pig sinoatrial node and right atrial appendage (auricle). In the working myocardium, NAD(+) and Ap4A in concentrations of 10(-5) and 10(-4) M had no effect on resting potential, but significantly reduced the duration of action potentials; the most pronounced decrease was found at 25% repolarization. In the primary pacemaker of the sinoatrial node, both concentrations of NAD(+) and Ap4A induced hyperpolarization and reduction in the rate of slow diastolic depolarization, but significant slowing of the sinus rhythm was produced by these substances only in the concentration of 10(-4) M. Moreover, AP shortening and marked acceleration of AP upstroke were observed in the pacemaker myocardium after application of polyphosphates. Comparative analysis of the effects of NAD(+) and Ap4A in the working and pacemaker myocardium drove us to a hypothesis on inhibitory effects of these substances on L-type calcium current accompanied by stimulation of one or several potassium currents, which induce enhancement of repolarization and hyperpolarization of membranes probably mediated by the activation of purine receptors.

  10. Upregulation of mitochondrial NAD+ levels impairs the clonogenicity of SSEA1+ glioblastoma tumor-initiating cells.

    PubMed

    Son, Myung Jin; Ryu, Jae-Sung; Kim, Jae Yun; Kwon, Youjeong; Chung, Kyung-Sook; Mun, Seon Ju; Cho, Yee Sook

    2017-06-09

    Emerging evidence has emphasized the importance of cancer therapies targeting an abnormal metabolic state of tumor-initiating cells (TICs) in which they retain stem cell-like phenotypes and nicotinamide adenine dinucleotide (NAD + ) metabolism. However, the functional role of NAD + metabolism in regulating the characteristics of TICs is not known. In this study, we provide evidence that the mitochondrial NAD + levels affect the characteristics of glioma-driven SSEA1 + TICs, including clonogenic growth potential. An increase in the mitochondrial NAD + levels by the overexpression of the mitochondrial enzyme nicotinamide nucleotide transhydrogenase (NNT) significantly suppressed the sphere-forming ability and induced differentiation of TICs, suggesting a loss of the characteristics of TICs. In addition, increased SIRT3 activity and reduced lactate production, which are mainly observed in healthy and young cells, appeared following NNT-overexpressed TICs. Moreover, in vivo tumorigenic potential was substantially abolished by NNT overexpression. Conversely, the short interfering RNA-mediated knockdown of NNT facilitated the maintenance of TIC characteristics, as evidenced by the increased numbers of large tumor spheres and in vivo tumorigenic potential. Our results demonstrated that targeting the maintenance of healthy mitochondria with increased mitochondrial NAD + levels and SIRT3 activity could be a promising strategy for abolishing the development of TICs as a new therapeutic approach to treating aging-associated tumors.

  11. NAD+ Supplementation Attenuates Methylmercury Dopaminergic and Mitochondrial Toxicity in Caenorhabditis Elegans

    PubMed Central

    Caito, Samuel W.; Aschner, Michael

    2016-01-01

    Methylmercury (MeHg) is a neurotoxic contaminant of our fish supply that has been linked to dopaminergic (DAergic) dysfunction that characterizes Parkinson’s disease. We have previously shown that MeHg causes both morphological and behavioral changes in the Caenorhabditis elegans DAergic neurons that are associated with oxidative stress. We were therefore interested in whether the redox sensitive cofactor nicotinamide adenine dinucleotide (NAD+) may be affected by MeHg and whether supplementation of NAD + may prevent MeHg-induced toxicities. Worms treated with MeHg showed depletion in cellular NAD + levels, which was prevented by NAD + supplementation prior to MeHg treatment. NAD + supplementation also prevented DAergic neurodegeneration and deficits in DAergic-dependent behavior upon MeHg exposure. In a mutant worm line that cannot synthesize NAD + from nicotinamide, MeHg lethality and DAergic behavioral deficits were more sensitive to MeHg than wildtype worms, demonstrating the importance of NAD + in MeHg toxicity. In wildtype worms, NAD + supplementation provided protection from MeHg-induced oxidative stress and mitochondrial dysfunction. These data show the importance of NAD + levels in the response to MeHg exposure. NAD + supplementation may be beneficial for MeHg-induced toxicities and preventing cellular damage involved in Parkinson’s disease. PMID:26865665

  12. Independent AMP and NAD signaling regulates C2C12 differentiation and metabolic adaptation.

    PubMed

    Hsu, Chia George; Burkholder, Thomas J

    2016-12-01

    The balance of ATP production and consumption is reflected in adenosine monophosphate (AMP) and nicotinamide adenine dinucleotide (NAD) content and has been associated with phenotypic plasticity in striated muscle. Some studies have suggested that AMPK-dependent plasticity may be an indirect consequence of increased NAD synthesis and SIRT1 activity. The primary goal of this study was to assess the interaction of AMP- and NAD-dependent signaling in adaptation of C2C12 myotubes. Changes in myotube developmental and metabolic gene expression were compared following incubation with 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) and nicotinamide mononucleotide (NMN) to activate AMPK- and NAD-related signaling. AICAR showed no effect on NAD pool or nampt expression but significantly reduced histone H3 acetylation and GLUT1, cytochrome C oxidase subunit 2 (COX2), and MYH3 expression. In contrast, NMN supplementation for 24 h increased NAD pool by 45 % but did not reduce histone H3 acetylation nor promote mitochondrial gene expression. The combination of AMP and NAD signaling did not induce further metabolic adaptation, but NMN ameliorated AICAR-induced myotube reduction. We interpret these results as indication that AMP and NAD contribute to C2C12 differentiation and metabolic adaptation independently.

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

    PubMed

    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 (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.

  14. Synthesis and characterization of Ag+-decorated poly(glycidyl methacrylate) microparticle design for the adsorption of nucleic acids.

    PubMed

    Erol, Kadir; Uzunoglu, Aytekin; Köse, Kazım; Sarıca, Büşra; Avcı, Emre; Köse, Dursun A

    2018-04-01

    In this study, we report on the adsorption of RNA and DNA molecules by exploiting the high binding affinity of these nucleic acids to Ag + ions anchored on magnetic poly(glycidyl methacrylate) (PGMA) microparticles. PGMA microparticles were synthesized and modified with nicotinamide which enabled to anchor Ag + ions on the surface. The successful preparation of PGMA was confirmed by the presence of characteristic FTIR peaks. The ESR results showed that the incorporation of FeNi salt to the polymeric structure provided a magnetic property to the microparticles. The amount of nicotinamide and Ag + ions used to modify the surface of the particles were found to be 1.79 wt% and 52.6 mg Ag/g microparticle, respectively. The high affinity of nucleic acids to Ag + ions were exploited for the adsorption studies. At the optimum working conditions, the adsorption capacity of microparticles was found to be 40.1 and 11.48 mg nucleic acid/g microparticle for RNA and DNA, respectively. Our study indicated that the use of novel Ag + -decorated magnetic PGMA particles can be successfully employed as adsorbents for fast, easy, and cost-friendly adsorption of nucleic acids with high purity as well as high in quantity. Copyright © 2018 Elsevier B.V. All rights reserved.

  15. Nicotinamide Riboside Opposes Type 2 Diabetes and Neuropathy in Mice

    PubMed Central

    Trammell, Samuel A.J.; Weidemann, Benjamin J.; Chadda, Ankita; Yorek, Matthew S.; Holmes, Amey; Coppey, Lawrence J.; Obrosov, Alexander; Kardon, Randy H.; Yorek, Mark A.; Brenner, Charles

    2016-01-01

    Male C57BL/6J mice raised on high fat diet (HFD) become prediabetic and develop insulin resistance and sensory neuropathy. The same mice given low doses of streptozotocin are a model of type 2 diabetes (T2D), developing hyperglycemia, severe insulin resistance and diabetic peripheral neuropathy involving sensory and motor neurons. Because of suggestions that increased NAD+ metabolism might address glycemic control and be neuroprotective, we treated prediabetic and T2D mice with nicotinamide riboside (NR) added to HFD. NR improved glucose tolerance, reduced weight gain, liver damage and the development of hepatic steatosis in prediabetic mice while protecting against sensory neuropathy. In T2D mice, NR greatly reduced non-fasting and fasting blood glucose, weight gain and hepatic steatosis while protecting against diabetic neuropathy. The neuroprotective effect of NR could not be explained by glycemic control alone. Corneal confocal microscopy was the most sensitive measure of neurodegeneration. This assay allowed detection of the protective effect of NR on small nerve structures in living mice. Quantitative metabolomics established that hepatic NADP+ and NADPH levels were significantly degraded in prediabetes and T2D but were largely protected when mice were supplemented with NR. The data justify testing of NR in human models of obesity, T2D and associated neuropathies. PMID:27230286

  16. Nicotinamide Riboside Opposes Type 2 Diabetes and Neuropathy in Mice.

    PubMed

    Trammell, Samuel A J; Weidemann, Benjamin J; Chadda, Ankita; Yorek, Matthew S; Holmes, Amey; Coppey, Lawrence J; Obrosov, Alexander; Kardon, Randy H; Yorek, Mark A; Brenner, Charles

    2016-05-27

    Male C57BL/6J mice raised on high fat diet (HFD) become prediabetic and develop insulin resistance and sensory neuropathy. The same mice given low doses of streptozotocin are a model of type 2 diabetes (T2D), developing hyperglycemia, severe insulin resistance and diabetic peripheral neuropathy involving sensory and motor neurons. Because of suggestions that increased NAD(+) metabolism might address glycemic control and be neuroprotective, we treated prediabetic and T2D mice with nicotinamide riboside (NR) added to HFD. NR improved glucose tolerance, reduced weight gain, liver damage and the development of hepatic steatosis in prediabetic mice while protecting against sensory neuropathy. In T2D mice, NR greatly reduced non-fasting and fasting blood glucose, weight gain and hepatic steatosis while protecting against diabetic neuropathy. The neuroprotective effect of NR could not be explained by glycemic control alone. Corneal confocal microscopy was the most sensitive measure of neurodegeneration. This assay allowed detection of the protective effect of NR on small nerve structures in living mice. Quantitative metabolomics established that hepatic NADP(+) and NADPH levels were significantly degraded in prediabetes and T2D but were largely protected when mice were supplemented with NR. The data justify testing of NR in human models of obesity, T2D and associated neuropathies.

  17. Celecoxib:Nicotinamide Dissociation: Using Excipients to Capture the Cocrystal's Potential

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Remenar,J.; Peterson, M.; Stephens, P.

    2007-01-01

    The cocrystal of celecoxib and nicotinamide (Cel:Nic) was crystallized from chloroform in a 1:1 ratio, and the structure has been solved from powder X-ray diffraction data. The dissolution and solubility of Cel:Nic are medium dependent and can be attributed to differences in conversion of Cel:Nic to celecoxib polymorphs I and III (Cel-I and Cel-III). The presence of low concentrations of surfactants facilitates the rapid conversion of neat Cel:Nic to large aggregates of Cel-III that dissolve more slowly than commercial Cel-III into 1% SDS solution. In contrast, combinations of Cel:Nic with both 1-10% solid SDS and PVP wet rapidly and convertmore » to a mixture of amorphous celecoxib and a micron-sized crystalline celecoxib form IV (Cel-IV), which has recently been shown to be up to 4-fold more bioavailable than marketed Cel-III. More than 90% of the suspended material dissolves within 2 min at 37 C when transferred to 1% SDS solution. This example highlights the importance of exploring the form conversion of cocrystals in aqueous media prior to pharmacokinetic studies, and illustrates the potential of simple formulations to overcome the limitations caused by rapid dissociation of cocrystals and recrystallization of poorly soluble forms in aqueous media.« less

  18. Celecoxib: Nicotinamide Dissociateion: Using Excipients to Capture the Cocrystal's Potential

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Remenar,J.; Peterson, M.; Stephens, P.

    2007-01-01

    The cocrystal of celecoxib and nicotinamide (Cel:Nic) was crystallized from chloroform in a 1:1 ratio, and the structure has been solved from powder X-ray diffraction data. The dissolution and solubility of Cel:Nic are medium dependent and can be attributed to differences in conversion of Cel:Nic to celecoxib polymorphs I and III (Cel-I and Cel-III). The presence of low concentrations of surfactants facilitates the rapid conversion of neat Cel:Nic to large aggregates of Cel-III that dissolve more slowly than commercial Cel-III into 1% SDS solution. In contrast, combinations of Cel:Nic with both 1-10% solid SDS and PVP wet rapidly and convertmore » to a mixture of amorphous celecoxib and a micron-sized crystalline celecoxib form IV (Cel-IV), which has recently been shown to be up to 4-fold more bioavailable than marketed Cel-III. More than 90% of the suspended material dissolves within 2 min at 37 C when transferred to 1% SDS solution. This example highlights the importance of exploring the form conversion of cocrystals in aqueous media prior to pharmacokinetic studies, and illustrates the potential of simple formulations to overcome the limitations caused by rapid dissociation of cocrystals and recrystallization of poorly soluble forms in aqueous media.« less

  19. Amino Acid and Vitamin Requirements of Several Bacteroides Strains

    PubMed Central

    Quinto, Grace

    1966-01-01

    Nutritional studies were performed on nine Bacteroides strains, by use of the methodology and media of anaerobic rumen microbiology. Ristella perfoetens CCI required l-arginine hydrochloride, l-tryptophan, l-leucine, l-histidine hydrochloride, l-cysteine hydrochloride, dl-valine, dl-tyrosine, and the vitamin calcium-d-pantothenate, since scant turbidity developed in media without these nutrients. R. perfoetens was stimulated by glycine, dl-lysine hydrochloride, dl-isoleucine, l-proline, l-glutamic acid, dl-alanine, dl-phenylalanine, dl-methionine, and the vitamins nicotinamide and p-aminobenzoic acid, since maximal turbidity developed more slowly in media without these nutrients than in complete medium. Medium A-23, which was devised for R. perfoetens, contained salts, 0.0002% nicotinamide and calcium d-pantothenate, 0.00001% p-aminobenzoic acid, 0.044% l-tryptophan, 0.09% l-glutamic acid, and 0.1% of the other 13 amino acids listed above. Zuberella clostridiformis and seven strains of R. pseudoinsolita did not require vitamins, and showed no absolute requirement for any one amino acid. Various strains produced maximal turbidity more slowly in media deficient in l-proline, glycine, l-glutamic acid, dl-serine, l-histidine hydrochloride, dl-alanine, or l-cysteine hydrochloride, than in complete medium. These eight strains grew optimally in medium A-23 plus 0.1% dl-serine but without vitamins. PMID:16349673

  20. In situ monitoring of cocrystals in formulation development using low-frequency Raman spectroscopy.

    PubMed

    Otaki, Takashi; Tanabe, Yuta; Kojima, Takashi; Miura, Masaru; Ikeda, Yukihiro; Koide, Tatsuo; Fukami, Toshiro

    2018-05-05

    In recent years, to guarantee a quality-by-design approach to the development of pharmaceutical products, it is important to identify properties of raw materials and excipients in order to determine critical process parameters and critical quality attributes. Feedback obtained from real-time analyses using various process analytical technology (PAT) tools has been actively investigated. In this study, in situ monitoring using low-frequency (LF) Raman spectroscopy (10-200 cm -1 ), which may have higher discriminative ability among polymorphs than near-infrared spectroscopy and conventional Raman spectroscopy (200-1800 cm -1 ), was investigated as a possible application to PAT. This is because LF-Raman spectroscopy obtains information about intermolecular and/or lattice vibrations in the solid state. The monitoring results obtained from Furosemide/Nicotinamide cocrystal indicate that LF-Raman spectroscopy is applicable to in situ monitoring of suspension and fluidized bed granulation processes, and is an effective technique as a PAT tool to detect the conversion risk of cocrystals. LF-Raman spectroscopy is also used as a PAT tool to monitor reactions, crystallizations, and manufacturing processes of drug substances and products. In addition, a sequence of conversion behaviors of Furosemide/Nicotinamide cocrystals was determined by performing in situ monitoring for the first time. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Caffeine at a Moderate Dose Did Not Affect the Skeletal System of Rats with Streptozotocin-Induced Diabetes.

    PubMed

    Folwarczna, Joanna; Janas, Aleksandra; Cegieła, Urszula; Pytlik, Maria; Śliwiński, Leszek; Matejczyk, Magdalena; Nowacka, Anna; Rudy, Karolina; Krivošíková, Zora; Štefíková, Kornélia; Gajdoš, Martin

    2017-10-30

    Diabetes may lead to the development of osteoporosis. Coffee drinking, apart from its health benefits, is taken into consideration as an osteoporosis risk factor. Data from human and animal studies on coffee and caffeine bone effects are inconsistent. The aim of the study was to investigate effects of caffeine at a moderate dose on the skeletal system of rats in two models of experimental diabetes induced by streptozotocin. Effects of caffeine administered orally (20 mg/kg aily for four weeks) were investigated in three-month-old female Wistar rats, which, two weeks before the start of caffeine administration, received streptozotocin (60 mg/kg, intraperitoneally) alone or streptozotocin after nicotinamide (230 mg/kg, intraperitoneally). Bone turnover markers, mass, mineral density, histomorphometric parameters, and mechanical properties were examined. Streptozotocin induced diabetes, with profound changes in the skeletal system due to increased bone resorption and decreased bone formation. Although streptozotocin administered after nicotinamide induced slight increases in glucose levels at the beginning of the experiment only, slight, but significant unfavorable changes in the skeletal system were demonstrated. Administration of caffeine did not affect the investigated skeletal parameters of rats with streptozotocin-induced disorders. In conclusion, caffeine at a moderate dose did not exert a damaging effect on the skeletal system of diabetic rats.

  2. Redox-linked Conformational Dynamics in Apoptosis Inducing Factor

    PubMed Central

    Sevrioukova, Irina F.

    2009-01-01

    Apoptosis inducing factor (AIF) is a bifunctional mitochondrial flavoprotein critical for energy metabolism and induction of caspase-independent apoptosis, whose exact role in normal mitochondria remains unknown. Upon reduction with NADH, AIF undergoes dimerization and forms tight, long-lived FADH2-NAD charge-transfer complexes (CTC) proposed to be functionally important. To get a deeper insight into structure/function relations and redox mechanism of this vitally important protein, we determined the x-ray structures of oxidized and NADH-reduced forms of naturally folded recombinant murine AIF. Our structures reveal that CTC with the pyridine nucleotide is stabilized by (i) π-stacking interactions between coplanar nicotinamide, isoalloxazine and Phe309 rings, (ii) rearrangement of multiple aromatic residues in the C-terminal domain, likely serving as an electron delocalization site, and (iii) an extensive hydrogen-bonding network involving His453, a key residue undergoing a conformational switch to directly interact and orient the nicotinamide in position optimal for charge transfer. Via the His453-containing peptide, redox changes in the active site are transmitted to the surface, promoting AIF dimerization and restricting access to a primary nuclear localization signal through which the apoptogenic form is transported to the nucleus. Structural findings agree with the biochemical data and support the hypothesis that both normal and apoptogenic functions of AIF are controlled by NADH. PMID:19447115

  3. Photosensitized oxidation of nicotinamide adenine dinucleotide by diethoxyphosphorus(V)tetraphenylporphyrin and its fluorinated derivative: Possibility of chain reaction.

    PubMed

    Hirakawa, Kazutaka; Murata, Atsushi

    2018-01-05

    Water-soluble porphyrins, diethoxyphosphorus(V)tetraphenylporphyrin (EtP(V)TPP) and its fluorinated analogue (FEtP(V)TPP), decreased the typical absorption around 340nm of nicotinamide adenine dinucleotide (NADH) under visible light irradiation, indicating oxidative decomposition. A singlet oxygen quencher, sodium azide, and a triplet quencher, potassium iodide, slightly inhibited photosensitized NADH oxidation. However, these inhibitory effects were very small. Furthermore, the fluorescence lifetime of these P(V)porphyrins was decreased by NADH, suggesting the contribution of electron transfer to the singlet excited (S 1 ) state of P(V)porphyrin. The redox potential measurement supports the electron transfer-mediated oxidation of NADH. The quantum yields of NADH photodecomposition by P(V)porphyrins could be estimated from the kinetic data and the effect of these quenchers on NADH oxidation. The obtained values suggest that the electron accepting by the S 1 states of P(V)porphyrins triggers a chain reaction of NADH oxidation. This photosensitized reaction may play an important role in the photocytotoxicity of P(V)porphyrins. The axial ligand fluorination of P(V)porphyrins improved electron accepting ability. However, fluorination slightly suppressed static interaction with NADH, resulting in decreased oxidation quantum yield. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Defining the Structural Basis for Allosteric Product Release from E. coli Dihydrofolate Reductase Using NMR Relaxation Dispersion.

    PubMed

    Oyen, David; Fenwick, R Bryn; Aoto, Phillip C; Stanfield, Robyn L; Wilson, Ian A; Dyson, H Jane; Wright, Peter E

    2017-08-16

    The rate-determining step in the catalytic cycle of E. coli dihydrofolate reductase is tetrahydrofolate (THF) product release, which can occur via an allosteric or an intrinsic pathway. The allosteric pathway, which becomes accessible when the reduced cofactor NADPH is bound, involves transient sampling of a higher energy conformational state, greatly increasing the product dissociation rate as compared to the intrinsic pathway that obtains when NADPH is absent. Although the kinetics of this process are known, the enzyme structure and the THF product conformation in the transiently formed excited state remain elusive. Here, we use side-chain proton NMR relaxation dispersion measurements, X-ray crystallography, and structure-based chemical shift predictions to explore the structural basis of allosteric product release. In the excited state of the E:THF:NADPH product release complex, the reduced nicotinamide ring of the cofactor transiently enters the active site where it displaces the pterin ring of the THF product. The p-aminobenzoyl-l-glutamate tail of THF remains weakly bound in a widened binding cleft. Thus, through transient entry of the nicotinamide ring into the active site, the NADPH cofactor remodels the enzyme structure and the conformation of the THF to form a weakly populated excited state that is poised for rapid product release.

  5. A critical role of nicotinamide phosphoribosyltransferase in human telomerase reverse transcriptase induction by resveratrol in aortic smooth muscle cells

    PubMed Central

    Huang, Peixin; Riordan, Sean M.; Heruth, Daniel P.; Grigoryev, Dmitry N.; Zhang, Li Qin; Ye, Shui Qing

    2015-01-01

    Aging is the predominant risk factor for cardiovascular diseases and contributes to a considerably more severe outcome in patients with acute myocardial infarction. Resveratrol, a polyphenol found in red wine, is a caloric restriction mimetic with potential anti-aging properties which has emerged as a beneficial nutraceutical for patients with cardiovascular disease. Although resveratrol is widely consumed as a nutritional supplement, its mechanism of action remains to be elucidated fully. Here, we report that resveratrol activates human nicotinamide phosphoribosyltransferase (NAMPT), SIRT4 and telomerase reverse transcriptase (hTERT) in human aortic smooth muscle cells. Similar observations were obtained in resveratrol treated C57BL/6J mouse heart and liver tissues. Resverotrol can also augment telomerase activity in both human pulmonary microvascular endothelial cells and A549 cells. Blocking NAMPT and SIRT4 expression prevents induction of hTERT in human aortic smooth muscle cells while overexpression of NAMPT elevates the telomerase activity induced by resveratrol in A549 cells. Together, these results identify a NAMPT-SIRT4-hTERT axis as a novel mechanism by which resveratrol may affect the anti-aging process in human aortic smooth muscle cells, mouse hearts and other cells. These findings enrich our understanding of the positive effects of resveratrol in human cardiovascular diseases. PMID:25926556

  6. HILIC separation and quantitation of water-soluble vitamins using diol column.

    PubMed

    Karatapanis, Andreas E; Fiamegos, Yiannis C; Stalikas, Constantine D

    2009-04-01

    Hydrophilic interaction liquid-chromatography (HILIC) in conjunction with diode array detection has been applied for the separation of selected-water-soluble vitamins using an end-capped HILIC-diol column. Vitamins with significant biological importance, such as thiamine (B(1)), riboflavin (B(2)), nicotinic acid (B(3)), nicotinamide (B(3)), pyridoxine (B(6)), folic acid (B(9)), cyanocobalamin (B(12)) and ascorbic acid (vitamin C) were simultaneously separated. Chromatographic conditions including type and percentage of organic modifier in the mobile phase, pH, type and concentration of buffer salt and flow rate were investigated. ACN was shown to offer superior separation for the compounds tested as compared to methanol, isopropanol and THF. Isocratic separation and analysis were achieved for six vitamins (B(1), B(2), nicotinic acid/nicotinamide, B(6) and C) at ACN-H(2)O 90:10, containing ammonium acetate 10 mM, triethylamine 20 mM, pH 5.0, using a flow rate of 0.8 mL/min, while a gradient was necessary to resolve a mixture of all eight water-soluble vitamins. The HILIC method was validated and successfully applied to the analysis of a pharmaceutical formulation and an energy drink negating the need for time consuming clean-up steps.

  7. Fluorescence decay kinetics and imaging of NAD(P)H and flavins as metabolic indicators

    NASA Astrophysics Data System (ADS)

    Schneckenburger, Herbert; Koenig, Karsten

    1992-07-01

    The intrinsic fluorescence of various cell cultures in the blue and green spectral range has been attributed mainly to hydrated nicotinamide adenine dinucleotide (NADH) and flavin molecules. Their fluorescence decay curves were measured with subnanosecond resolution. The reduced coenzymes NADH and hydrated nicotinamide adenine dinucleotide phosphate NADPH, both showed a biexponential decay pattern in solution with similar time constants, but different relative intensities of the two components. They could thus be distinguished from one another as well as from their oxidized forms. The NADPH fluorescence of Saccharomyces cerevisiae was located within the cytoplasm and its organelles and was by about a factor of 4 higher for respiratory-deficient than for intact yeast strains. Intracellular flavin fluorescence showed a triexponential behavior--probably due to a superposition of protein-bound and free flavin molecules. The lifetime of the shortest component varied within the range of 0.20 to 0.50 ns between respiratory-deficient and intact yeast strains, and the relative intensity of this component was most pronounced for the intact strain DL1. Time- resolved fluorescence seems therefore to be an appropriate method of probe the function of the respiratory chain and--in the further step--to differentiate between various types of cells and tissues in medical diagnosis or environmental research.

  8. Blood modulates the kinetics of reactive oxygen release in pancreatic ischemia-reperfusion injury.

    PubMed

    Neeff, Hannes P; Sommer, Olaf; Meyer, Sebastian; Tinelli, Anja; Scholtes, Moritz; Hopt, Ulrich T; Drognitz, Oliver; von Dobschuetz, Ernst

    2012-10-01

    Reason for the unsuccessful use of antioxidants in transplantation might be the unknown kinetics of reactive oxygen species (ROS) release. In this study, we compared the kinetics of ROS release from rat pancreata in the presence and absence of blood. In vivo, ischemia-reperfusion injury (IRI) was induced in pancreata of male Wistar rats by occlusion of the arterial blood supply for 1 or 2 hours. In vitro, isolated pancreata were single-pass perfused with Krebs-Henseleit bicarbonate solution. Reactive oxygen species were quantified by electron spin resonance spectroscopy using CMH (1-hydroxy-3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine) as spin label. Thiols (glutathione), nicotinamide adenine dinucleotide phosphate-oxidase activity, myeloperoxidase activity, and adenosine triphosphate content were measured. During reperfusion, an increase in IRI-induced ROS in arterial blood was noted after 2 hours of warm ischemia. In sharp contrast, ROS release was immediate and short lived in blood-free perfused organs. The degree of tissue damage correlated with nicotinamide adenine dinucleotide phosphate-oxidase activity and adenosine triphosphate content. Antioxidative capacity of tissues was reduced. Electron spin resonance spectroscopy in conjunction with spin labels allows for the detection of ROS kinetics in pancreatic IRI. Reactive oxygen species kinetics are dependent on the length of the ischemic period and the presence or absence of blood.

  9. Label-free in vivo flow cytometry in zebrafish using two-photon autofluorescence imaging.

    PubMed

    Zeng, Yan; Xu, Jin; Li, Dong; Li, Li; Wen, Zilong; Qu, Jianan Y

    2012-07-01

    We demonstrate a label-free in vivo flow cytometry in zebrafish blood vessels based on two-photon excited autofluorescence imaging. The major discovery in this work is the strong autofluorescence emission from the plasma in zebrafish blood. The plasma autofluorescence provides excellent contrast for visualizing blood vessels and counting blood cells. In addition, the cellular nicotinamide adenine dinucleotide autofluorescence enables in vivo imaging and counting of white blood cells (neutrophils).

  10. Mutations in Nicotinamide Nucleotide Transhydrogenase (NNT) cause familial glucocorticoid deficiency

    PubMed Central

    Meimaridou, Eirini; Kowalczyk, Julia; Guasti, Leonardo; Hughes, Claire R.; Wagner, Florian; Frommolt, Peter; Nürnberg, Peter; Mann, Nicholas P.; Banerjee, Ritwik; Saka, H. Nurcin; Chapple, J. Paul; King, Peter J.; Clark, Adrian J.L.; Metherell, Louise A.

    2012-01-01

    Using targeted exome sequencing we identified mutations in NNT, an antioxidant defence gene, in patients with familial glucocorticoid deficiency. In mice with Nnt loss, higher levels of adrenocortical cell apoptosis and impaired glucocorticoid production were observed. NNT knockdown in a human adrenocortical cell line resulted in impaired redox potential and increased ROS levels. Our results suggest that NNT may have a role in ROS detoxification in human adrenal glands. PMID:22634753

  11. Engineered Approaches to In Situ Bioremediation of Chlorinated Solvents: Fundamentals and Field Applications

    DTIC Science & Technology

    2000-07-01

    scale system that consists of three injection wells currently is being installed at the site. The wells will deliver fructose corn syrup to the...aerobic reaction). The energy gained is stored as high energy compounds, such as ATP and low- energy compounds, such as nicotinamide adenine...processes at high redox potential values is limited; efficiency improves as the redox potential decreases. Pilot studies have been conducted at a variety of

  12. Biomarkers and Biological Spectral Imaging

    DTIC Science & Technology

    2001-01-23

    Image t iZ ~ Rotator SSteping r De m oo ontroler Frmegabe (single ams) ... Software -= • . ... PCCm ue Data acquisition Rotator control PC Co puterImage...the depth of bum injury", Bums, 7, pp. 197-202, 1981. 7. R. A. De Blasi, M. Cope, C. Elwell, F. Safoue and M. Ferrari, "Noninvasive measurement of...nicotinamide adenine dinucleotide (NADH), oxidized flavin adenine dinucleotide (FAD) and porphyrins. A number of studies have shown that the measured

  13. Salvaging hope: Is increasing NAD(+) a key to treating mitochondrial myopathy?

    PubMed

    Lightowlers, Robert N; Chrzanowska-Lightowlers, Zofia M A

    2014-06-01

    Mitochondrial diseases can arise from mutations either in mitochondrial DNA or in nuclear DNA encoding mitochondrially destined proteins. Currently, there is no cure for these diseases although treatments to ameliorate a subset of the symptoms are being developed. In this issue of EMBO Molecular Medicine, Khan et al (2014) use a mouse model to test the efficacy of a simple dietary supplement of nicotinamide riboside to treat and prevent mitochondrial myopathies.

  14. Chemical synthesis of benzamide riboside.

    PubMed

    Krohn, K; Dörner, H; Zukowski, M

    2002-04-01

    The C-glycosidic nicotinamide riboside analogue (1) was prepared by reaction of ribonolactone 16 with the lithiated 2-oxazoline 13 followed by triethylsilane reduction of the hemiacetal 17 to the tetrahydrofurane 18. Cleavage of the oxazoline group in 20 to the acid 21, conversion of the acid chloride 22 to the amide 23, and hydrogenative debenzylation afforded the benzamide riboside 1. Phosphorylation of the acetonide 26 and acid-catalyzed cleavage of the resulting ketal yielded the pseudonucleotide 27.

  15. Printable Organic Nanoelectronics for Memory, Sensors and Display

    DTIC Science & Technology

    2014-02-01

    central ion but associated with ring- based processes during oxidation and reduction. The electrochromic behaviour of the film was examined by cyclic...Fluorine-doped tin oxide 12  satDI Saturation current 9 scI Short circuit current 10 LiClO4 Lithium perchlorate 14 NADH reduced nicotinamide...resistor R and capacitor C , connected in parallel. The net current I is the sum of the circulating current and displacement components in the form

  16. Nicotinamide riboside restores cognition through an upregulation of proliferator-activated receptor-γ coactivator 1α regulated β-secretase 1 degradation and mitochondrial gene expression in Alzheimer's mouse models.

    PubMed

    Gong, Bing; Pan, Yong; Vempati, Prashant; Zhao, Wei; Knable, Lindsay; Ho, Lap; Wang, Jun; Sastre, Magdalena; Ono, Kenjiro; Sauve, Anthony A; Pasinetti, Giulio M

    2013-06-01

    Nicotinamide adenine dinucleotide (NAD)(+), a coenzyme involved in redox activities in the mitochondrial electron transport chain, has been identified as a key regulator of the lifespan-extending effects, and the activation of NAD(+) expression has been linked with a decrease in beta-amyloid (Aβ) toxicity in Alzheimer's disease (AD). Nicotinamide riboside (NR) is a NAD(+) precursor, it promotes peroxisome proliferator-activated receptor-γ coactivator 1 (PGC)-1α expression in the brain. Evidence has shown that PGC-1α is a crucial regulator of Aβ generation because it affects β-secretase (BACE1) degradation. In this study we tested the hypothesis that NR treatment in an AD mouse model could attenuate Aβ toxicity through the activation of PGC-1α-mediated BACE1 degradation. Using the Tg2576 AD mouse model, using in vivo behavioral analyses, biochemistry assays, small hairpin RNA (shRNA) gene silencing and electrophysiological recording, we found (1) dietary treatment of Tg2576 mice with 250 mg/kg/day of NR for 3 months significantly attenuates cognitive deterioration in Tg2576 mice and coincides with an increase in the steady-state levels of NAD(+) in the cerebral cortex; (2) application of NR to hippocampal slices (10 μM) for 4 hours abolishes the deficits in long-term potentiation recorded in the CA1 region of Tg2576 mice; (3) NR treatment promotes PGC-1α expression in the brain coinciding with enhanced degradation of BACE1 and the reduction of Aβ production in Tg2576 mice. Further in vitro studies confirmed that BACE1 protein content is decreased by NR treatment in primary neuronal cultures derived from Tg2576 embryos, in which BACE1 degradation was prevented by PGC-1α-shRNA gene silencing; and (4) NR treatment and PGC-1α overexpression enhance BACE1 ubiquitination and proteasomal degradation. Our studies suggest that dietary treatment with NR might benefit AD cognitive function and synaptic plasticity, in part by promoting PGC-1α-mediated BACE1 ubiquitination and degradation, thus preventing Aβ production in the brain. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Salvaging hope: Is increasing NAD+ a key to treating mitochondrial myopathy?

    PubMed Central

    Lightowlers, Robert N; Chrzanowska-Lightowlers, Zofia MA

    2014-01-01

    Mitochondrial diseases can arise from mutations either in mitochondrial DNA or in nuclear DNA encoding mitochondrially destined proteins. Currently, there is no cure for these diseases although treatments to ameliorate a subset of the symptoms are being developed. In this issue of EMBO Molecular Medicine, Khan et al (2014) use a mouse model to test the efficacy of a simple dietary supplement of nicotinamide riboside to treat and prevent mitochondrial myopathies. PMID:24838280

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

    PubMed

    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.

  19. A water-forming NADH oxidase from Lactobacillus pentosus suitable for the regeneration of synthetic biomimetic cofactors

    PubMed Central

    Nowak, Claudia; Beer, Barbara; Pick, André; Roth, Teresa; Lommes, Petra; Sieber, Volker

    2015-01-01

    The cell-free biocatalytic production of fine chemicals by oxidoreductases has continuously grown over the past years. Since especially dehydrogenases depend on the stoichiometric use of nicotinamide pyridine cofactors, an integrated efficient recycling system is crucial to allow process operation under economic conditions. Lately, the variety of cofactors for biocatalysis was broadened by the utilization of totally synthetic and cheap biomimetics. Though, to date the regeneration has been limited to chemical or electrochemical methods. Here, we report an enzymatic recycling by the flavoprotein NADH-oxidase from Lactobacillus pentosus (LpNox). Since this enzyme has not been described before, we first characterized it in regard to its optimal reaction parameters. We found that the heterologously overexpressed enzyme only contained 13% FAD. In vitro loading of the enzyme with FAD, resulted in a higher specific activity towards its natural cofactor NADH as well as different nicotinamide derived biomimetics. Apart from the enzymatic recycling, which gives water as a by-product by transferring four electrons onto oxygen, unbound FAD can also catalyze the oxidation of biomimetic cofactors. Here a two electron process takes place yielding H2O2 instead. The enzymatic and chemical recycling was compared in regard to reaction kinetics for the natural and biomimetic cofactors. With LpNox and FAD, two recycling strategies for biomimetic cofactors are described with either water or hydrogen peroxide as by-product. PMID:26441891

  20. Near infra red spectroscopy as a multivariate process analytical tool for predicting pharmaceutical co-crystal concentration.

    PubMed

    Wood, Clive; Alwati, Abdolati; Halsey, Sheelagh; Gough, Tim; Brown, Elaine; Kelly, Adrian; Paradkar, Anant

    2016-09-10

    The use of near infra red spectroscopy to predict the concentration of two pharmaceutical co-crystals; 1:1 ibuprofen-nicotinamide (IBU-NIC) and 1:1 carbamazepine-nicotinamide (CBZ-NIC) has been evaluated. A partial least squares (PLS) regression model was developed for both co-crystal pairs using sets of standard samples to create calibration and validation data sets with which to build and validate the models. Parameters such as the root mean square error of calibration (RMSEC), root mean square error of prediction (RMSEP) and correlation coefficient were used to assess the accuracy and linearity of the models. Accurate PLS regression models were created for both co-crystal pairs which can be used to predict the co-crystal concentration in a powder mixture of the co-crystal and the active pharmaceutical ingredient (API). The IBU-NIC model had smaller errors than the CBZ-NIC model, possibly due to the complex CBZ-NIC spectra which could reflect the different arrangement of hydrogen bonding associated with the co-crystal compared to the IBU-NIC co-crystal. These results suggest that NIR spectroscopy can be used as a PAT tool during a variety of pharmaceutical co-crystal manufacturing methods and the presented data will facilitate future offline and in-line NIR studies involving pharmaceutical co-crystals. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  1. Antihyperglycemic activity of Albizzia lebbeck bark extract in streptozotocin-nicotinamide induced type II diabetes mellitus rats

    PubMed Central

    Patel, Priyank A.; Parikh, Mihir P.; Johari, Sarika; Gandhi, Tejal R.

    2015-01-01

    Introduction: Albizzia lebbeck (L.) Benth. (Family - Leguminosae) extract is a proven mast cell stabilizing agent. Mast cells are involved in the inflammatory processes leading to the diabetes mellitus. Aim: To evaluate the effect of A. lebbeck against experimentally induced type 2 diabetes mellitus in rats. Materials and Method: Female Sprague-Dawley rats were randomly allocated to six groups (n = 6). Diabetes was induced by single intraperitoneal injection of streptozotocin (50 mg/kg) given after 15 min of nicotinamide administration (110 mg/kg). Treatment with methanolic extract of A. lebbeck bark (MEAL) and metformin drug as standard was given for 21 days. Serum glucose (GLU) levels were measured on the 0 day and on 1st, 7th, 14th and 21st day after diabetes induction. After completion of study period, various biochemical parameters in serum such as - GLU, lipid profile, urea and creatinine were estimated. One-way analysis of variance followed with post-hoc Dunnett's test was used to analyse the data. Statistical significance for the values was set at P< 0.05. Results: MEAL significantly decreased the level of serum GLU, creatinine, urea, cholesterol, triglycerides, low-density lipoprotein-cholesterol, very low-density lipoprotein-cholesterol and increased high-density lipoprotein levels. Conclusion: A. lebbeck bark extract showed antihyperglycaemic activity along with antihyperlipidemic effect. PMID:27313423

  2. Loss of the RNA polymerase III repressor MAF1 confers obesity resistance.

    PubMed

    Bonhoure, Nicolas; Byrnes, Ashlee; Moir, Robyn D; Hodroj, Wassim; Preitner, Frédéric; Praz, Viviane; Marcelin, Genevieve; Chua, Streamson C; Martinez-Lopez, Nuria; Singh, Rajat; Moullan, Norman; Auwerx, Johan; Willemin, Gilles; Shah, Hardik; Hartil, Kirsten; Vaitheesvaran, Bhavapriya; Kurland, Irwin; Hernandez, Nouria; Willis, Ian M

    2015-05-01

    MAF1 is a global repressor of RNA polymerase III transcription that regulates the expression of highly abundant noncoding RNAs in response to nutrient availability and cellular stress. Thus, MAF1 function is thought to be important for metabolic economy. Here we show that a whole-body knockout of Maf1 in mice confers resistance to diet-induced obesity and nonalcoholic fatty liver disease by reducing food intake and increasing metabolic inefficiency. Energy expenditure in Maf1(-/-) mice is increased by several mechanisms. Precursor tRNA synthesis was increased in multiple tissues without significant effects on mature tRNA levels, implying increased turnover in a futile tRNA cycle. Elevated futile cycling of hepatic lipids was also observed. Metabolite profiling of the liver and skeletal muscle revealed elevated levels of many amino acids and spermidine, which links the induction of autophagy in Maf1(-/-) mice with their extended life span. The increase in spermidine was accompanied by reduced levels of nicotinamide N-methyltransferase, which promotes polyamine synthesis, enables nicotinamide salvage to regenerate NAD(+), and is associated with obesity resistance. Consistent with this, NAD(+) levels were increased in muscle. The importance of MAF1 for metabolic economy reveals the potential for MAF1 modulators to protect against obesity and its harmful consequences. © 2015 Bonhoure et al.; Published by Cold Spring Harbor Laboratory Press.

  3. Effect of Nicotinamide on the Photolysis of Riboflavin in Aqueous Solution

    PubMed Central

    Ahmad, Iqbal; Ahmed, Sofia; Sheraz, Muhammad Ali; Anwar, Zubair; Qadeer, Kiran; Noor, Adnan; Evstigneev, Maxim P.

    2016-01-01

    The photolysis of riboflavin (RF) in aqueous solution in the presence of nicotinamide (NA) by visible light has been studied in the pH range 1.0–12.0 and the various photoproducts have been identified as known compounds. RF has been determined in degraded solutions by a specific multicomponent spectrometric method in the presence of its photoproducts and NA. The second-order rate constants (k2) for the bimolecular interaction of RF and NA range from 0.54 (pH 1.0) to 9.66 M–1 min–1 (pH 12.0). The log k2–pH profile for the photolysis reaction follows a sigmoid curve showing a gradual increase in the rate of pH due to a change in the ionization behavior of the molecule. The lower rate in the acid region is probably due to protonation of the molecule since the cationic form of RF is less susceptible to photolysis than the neutral form. Similarly, a slowing of the rate in the alkaline region is due to anion formation of the molecule. NA is involved as an electron acceptor during the sequence of reactions and thus enhances the rate of photolysis of RF. Absorption and fluorescence measurements did not provide evidence for the complex formation between the two compounds under the present conditions. PMID:27222605

  4. Upregulation of mitochondrial NAD+ levels impairs the clonogenicity of SSEA1+ glioblastoma tumor-initiating cells

    PubMed Central

    Son, Myung Jin; Ryu, Jae-Sung; Kim, Jae Yun; Kwon, Youjeong; Chung, Kyung-Sook; Mun, Seon Ju; Cho, Yee Sook

    2017-01-01

    Emerging evidence has emphasized the importance of cancer therapies targeting an abnormal metabolic state of tumor-initiating cells (TICs) in which they retain stem cell-like phenotypes and nicotinamide adenine dinucleotide (NAD+) metabolism. However, the functional role of NAD+ metabolism in regulating the characteristics of TICs is not known. In this study, we provide evidence that the mitochondrial NAD+ levels affect the characteristics of glioma-driven SSEA1+ TICs, including clonogenic growth potential. An increase in the mitochondrial NAD+ levels by the overexpression of the mitochondrial enzyme nicotinamide nucleotide transhydrogenase (NNT) significantly suppressed the sphere-forming ability and induced differentiation of TICs, suggesting a loss of the characteristics of TICs. In addition, increased SIRT3 activity and reduced lactate production, which are mainly observed in healthy and young cells, appeared following NNT-overexpressed TICs. Moreover, in vivo tumorigenic potential was substantially abolished by NNT overexpression. Conversely, the short interfering RNA-mediated knockdown of NNT facilitated the maintenance of TIC characteristics, as evidenced by the increased numbers of large tumor spheres and in vivo tumorigenic potential. Our results demonstrated that targeting the maintenance of healthy mitochondria with increased mitochondrial NAD+ levels and SIRT3 activity could be a promising strategy for abolishing the development of TICs as a new therapeutic approach to treating aging-associated tumors. PMID:28604662

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

    PubMed

    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.

  6. Structural basis for the inhibition of poly(ADP-ribose) polymerases 1 and 2 by BMN 673, a potent inhibitor derived from dihydropyridophthalazinone

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aoyagi-Scharber, Mika, E-mail: maoyagi@bmrn.com; Gardberg, Anna S.; Yip, Bryan K.

    2014-08-29

    BMN 673, a novel PARP1/2 inhibitor in clinical development with substantial tumor cytotoxicity, forms extensive hydrogen-bonding and π-stacking in the nicotinamide pocket, with its unique disubstituted scaffold extending towards the less conserved edges of the pocket. These interactions might provide structural insight into the ability of BMN 673 to both inhibit catalysis and affect DNA-binding activity. Poly(ADP-ribose) polymerases 1 and 2 (PARP1 and PARP2), which are involved in DNA damage response, are targets of anticancer therapeutics. BMN 673 is a novel PARP1/2 inhibitor with substantially increased PARP-mediated tumor cytotoxicity and is now in later-stage clinical development for BRCA-deficient breast cancers.more » In co-crystal structures, BMN 673 is anchored to the nicotinamide-binding pocket via an extensive network of hydrogen-bonding and π-stacking interactions, including those mediated by active-site water molecules. The novel di-branched scaffold of BMN 673 extends the binding interactions towards the outer edges of the pocket, which exhibit the least sequence homology among PARP enzymes. The crystallographic structural analyses reported here therefore not only provide critical insights into the molecular basis for the exceptionally high potency of the clinical development candidate BMN 673, but also new opportunities for increasing inhibitor selectivity.« less

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

    PubMed

    Soares, Frederico L F; Carneiro, Renato L

    2017-06-05

    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. Copyright © 2017 Elsevier B.V. All rights reserved.

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

    PubMed Central

    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

  9. Hydrogen peroxide-induced injury of cells and its prevention by inhibitors of poly(ADP-ribose) polymerase.

    PubMed Central

    Schraufstatter, I U; Hyslop, P A; Hinshaw, D B; Spragg, R G; Sklar, L A; Cochrane, C G

    1986-01-01

    H2O2, in concentrations achieved in the proximity of stimulated leukocytes, induces injury and lysis of target cells. This may be an important aspect of inflammatory injury of tissues. Cell lysis in two target cells, the murine macrophage-like tumor cell line P388D1 and human peripheral lymphocytes, was found to be associated with activation of poly(ADP-ribose) polymerase (EC 2.4.2.30), a nuclear enzyme. This enzyme is activated under various conditions of DNA damage. Poly(ADP-ribose) polymerase utilizes nicotinamide adenine dinucleotide (NAD) as substrate and has been previously shown to consume NAD during exposure of cells to oxidants that was associated with inhibition of glycolysis, a decrease in cellular ATP, and cell death. In the current studies, inhibition of poly(ADP-ribose) polymerase by 3-aminobenzamide, nicotinamide, or theophylline in cells exposed to lethal concentrations of H2O2 prevented the sequence of events that eventually led to cell lysis--i.e., the decrease in NAD, followed by depletion of ATP, influx of extracellular Ca2+, actin polymerization and, finally, cell death. DNA damage, the initial stimulus for poly(ADP-ribose) polymerase activation, occurred despite the inhibition of this enzyme. Cells exposed to oxidant in the presence of the poly(ADP-ribose) polymerase inhibitor 3-aminobenzamide failed to demonstrate repair of DNA strand breaks. PMID:2941760

  10. Pyruvate dehydrogenase complex and nicotinamide nucleotide transhydrogenase constitute an energy consuming redox circuit

    PubMed Central

    Fisher-Wellman, Kelsey H.; Lin, Chien-Te; Ryan, Terence E.; Reese, Lauren R.; Gilliam, Laura A. A.; Cathey, Brook L.; Lark, Daniel S.; Smith, Cody D.; Muoio, Deborah M.; Neufer, P. Darrell

    2015-01-01

    SUMMARY Cellular proteins rely on reversible redox reactions to establish and maintain biological structure and function. How redox catabolic (NAD+:NADH) and anabolic (NADP+:NADPH) processes integrate during metabolism to maintain cellular redox homeostasis however is unknown. The present work identifies a continuously cycling, mitochondrial membrane potential-dependent redox circuit between the pyruvate dehydrogenase complex (PDHC) and nicotinamide nucleotide transhydrogenase (NNT). PDHC is shown to produce H2O2 in relation to reducing pressure within the complex. The H2O2 produced however is effectively masked by a continuously cycling redox circuit that links, via glutathione/thioredoxin, to NNT, which catalyzes the regeneration of NADPH from NADH at the expense of the mitochondrial membrane potential. The net effect is an automatic fine tuning of NNT-mediated energy expenditure to metabolic balance at the level of PDHC. In mitochondria, genetic or pharmacological disruptions in the PDHC-NNT redox circuit negate counterbalance changes in energy expenditure. At the whole animal level, mice lacking functional NNT (C57BL/6J) are characterized by lower energy expenditure rates, consistent with their well known susceptibility to diet-induced obesity. These findings suggest the integration of redox sensing of metabolic balance with compensatory changes in energy expenditure provides a potential mechanism by which cellular redox homeostasis is maintained and body weight is defended during periods of positive and negative energy balance. PMID:25643703

  11. The NAD+/PARP1/SIRT1 Axis in Aging.

    PubMed

    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.

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

    PubMed

    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.

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

    PubMed

    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.

  14. The NAD+ precursor nicotinic acid improves genomic integrity in human peripheral blood mononuclear cells after X-irradiation.

    PubMed

    Weidele, Kathrin; Beneke, Sascha; Bürkle, Alexander

    2017-04-01

    NAD + is an essential cofactor for enzymes catalyzing redox-reactions as well as an electron carrier in energy metabolism. Aside from this, NAD + consuming enzymes like poly(ADP-ribose) polymerases and sirtuins are important regulators involved in chromatin-restructuring processes during repair and epigenetics/transcriptional adaption. In order to replenish cellular NAD + levels after cleavage, synthesis starts from precursors such as nicotinamide, nicotinamide riboside or nicotinic acid to match the need for this essential molecule. In the present study, we investigated the impact of supplementation with nicotinic acid on resting and proliferating human mononuclear blood cells with a focus on DNA damage and repair processes. We observed that nicotinic acid supplementation increased NAD + levels as well as DNA repair efficiency and enhanced genomic stability evaluated by micronucleus test after x-ray treatment. Interestingly, resting cells displayed lower basal levels of DNA breaks compared to proliferating cells, but break-induction rates were identical. Despite similar levels of p53 protein upregulation after irradiation, higher NAD + concentrations led to reduced acetylation of this protein, suggesting enhanced SIRT1 activity. Our data reveal that even in normal primary human cells cellular NAD + levels may be limiting under conditions of genotoxic stress and that boosting the NAD + system with nicotinic acid can improve genomic stability. Copyright © 2017 Elsevier B.V. All rights reserved.

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

    NASA Astrophysics Data System (ADS)

    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.

  16. Diaqua­bis­(4-meth­oxy­benzoato-κO 1)bis­(nicotinamide-κN 1)cobalt(II) dihydrate

    PubMed Central

    Hökelek, Tuncer; Dal, Hakan; Tercan, Barış; Tenlik, Erdinç; Necefoğlu, Hacali

    2010-01-01

    In the mononuclear title compound, [Co(C8H7O3)2(C6H6N2O)2(H2O)2]·2H2O, the CoII ion is located on a crystallographic inversion center. The asymmetric unit is completed by one 4-meth­oxy­benzoate anion, one nicotinamide (NA) ligand and one coordinated and one uncoordinated water mol­ecule. All ligands act in a monodentate mode. The four O atoms in the equatorial plane around the CoII ion form a slightly distorted square-planar arrangement, while the slightly distorted octa­hedral coordination is completed by the two pyridine N atoms of the NA ligands in the axial positions. The dihedral angle between the carboxyl­ate group and the attached benzene ring is 6.47 (7)°, while the pyridine and benzene rings are oriented at a dihedral angle of 72.80 (4)°. An O—H⋯O hydrogen bond links the uncoordinated water mol­ecule to one of the carboxyl­ate groups. In the crystal structure, inter­molecular O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonds link the mol­ecules into a three-dimensional network. PMID:21588149

  17. Nicotinamide treatment ameliorates the course of experimental colitis mediated by enhanced neutrophil-specific antibacterial clearance.

    PubMed

    Bettenworth, Dominik; Nowacki, Tobias M; Ross, Matthias; Kyme, Pierre; Schwammbach, Daniela; Kerstiens, Linda; Thoennissen, Gabriela B; Bokemeyer, Carsten; Hengst, Karin; Berdel, Wolfgang E; Heidemann, Jan; Thoennissen, Nils H

    2014-07-01

    In previous studies, we could show that the B vitamin nicotinamide (NAM) enhanced antimicrobial activity of neutrophils. Here, we assessed the effects of NAM in two models of experimental colitis. Colitis was induced in C57BL/6 mice either by oral infection with Citrobacter rodentium or by DSS (dextran sodium sulphate) administration, and animals were systemically treated with NAM. Ex vivo bacterial clearance was assessed in murine and human whole blood, as well as isolated human neutrophils. In C. rodentium-induced colitis, NAM treatment resulted in markedly decreased systemic bacterial invasion, histological damage and increased fecal clearance of C. rodentium by up to 600-fold. In contrast, NAM had no effect when administered to neutrophil-depleted mice. Ex vivo stimulation of isolated human neutrophils, as well as murine and human whole blood with NAM led to increased clearance of C. rodentium and enhanced expression of antimicrobial peptides in neutrophils. Moreover, NAM treatment significantly ameliorated the course of DSS colitis, as assessed by body weight, histological damage and myeloperoxidase activity. Pharmacological application of NAM mediates beneficial effects in bacterial and chemically induced colitis. Future studies are needed to explore the clinical potential of NAM in the context of intestinal bacterial infections and human inflammatory bowel disease (IBD). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Two continuous coupled assays for ornithine-δ-aminotransferase.

    PubMed

    Juncosa, Jose I; Lee, Hyunbeom; Silverman, Richard B

    2013-09-15

    We have developed two new continuous coupled assays for ornithine-δ-aminotransferase (OAT) that are more sensitive than previous methods, measure activity in real time, and can be carried out in multiwell plates for convenience and high throughput. The first assay is based on the reduction of Δ(1)-pyrroline-5-carboxylate (P5C), generated from ornithine by OAT, using human pyrroline 5-carboxylate reductase 1 (PYCR1), which results in the concomitant oxidation of NADH (nicotinamide adenine dinucleotide, reduced form) to NAD⁺ (nicotinamide adenine dinucleotide, oxidized form). This procedure was found to be three times more sensitive than previous methods and is suitable for the study of small molecules as inhibitors or inactivators of OAT or as a method to determine OAT activity in unknown samples. The second method involves the detection of L-glutamate, produced during the regeneration of the cofactor pyridoxal 5'-phosphate (PLP) of OAT by an unamplified modification of the commercially available Amplex Red L-glutamate detection kit (Life Technologies). This assay is recommended for the determination of the substrate activity of small molecules against OAT; measuring the transformation of L-ornithine at high concentrations by this assay is complicated by the fact that it also acts as a substrate for the L-glutamate oxidase (GluOx) reporter enzyme. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Short communication: Nutrient consumption patterns of Lactobacillus acidophilus KLDS 1.0738 in controlled pH batch fermentations.

    PubMed

    Lv, Xuepeng; Liu, Gefei; Sun, Xiaomei; Chen, Hongyu; Sun, Jiahui; Feng, Zhen

    2017-07-01

    This work focused on elucidating the nutrient consumption patterns of Lactobacillus acidophilus to guide the design of media for high-cell-density culture. We investigated the nutrient consumption patterns of L. acidophilus KLDS 1.0738 in chemically defined media in controlled pH batch fermentations. The most abundantly consumed amino acids, vitamins, ions, and purines and pyrimidines were Glu and Gly, pyridoxine and nicotinamide, K + and PO 4 3- , and guanine and uracil, respectively. The highest consumption rates for amino acids, vitamins, ions, and purines and pyrimidines were Asp and Arg, folic acid and pyridoxine, Fe 2+ and Mn 2+ , and uracil and thymine, respectively. Furthermore, most of the amino acids, as well as guanine, thymine, pyridoxine, folic acid, nicotinamide, Mg 2+ , PO 4 3- , and K + had the highest bioavailability from the end of the lag growth phase to the mid-exponential growth phase. The overall consumption of glucose, adenine nucleotides, 2'-deoxyguanosine monohydrate, calcium pantothenate, Fe 2+ and Mn 2+ decreased with increasing average growth rate, indicating more effective use of these nutritional components at a higher average growth rate, as biomass yield based on nutritional component consumption increased. Our findings help to formulate complex media for high-cell-density cultivation and provide a theoretical basis for L. acidophilus feeding strategies. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  20. Extracellular visfatin activates gluconeogenesis in HepG2 cells through the classical PKA/CREB-dependent pathway.

    PubMed

    Choi, Y J; Choi, S-E; Ha, E S; Kang, Y; Han, S J; Kim, D J; Lee, K W; Kim, H J

    2014-04-01

    Adipokines reportedly affect hepatic gluconeogenesis, and the adipokine visfatin is known to be related to insulin resistance and type 2 diabetes. However, whether visfatin contributes to hepatic gluconeogenesis remains unclear. Visfatin, also known as nicotinamide phosphoribosyltransferase (NAMPT), modulates sirtuin1 (SIRT1) through the regulation of nicotinamide adenine dinucleotide (NAD). Therefore, we investigated the effect of extracellular visfatin on glucose production in HepG2 cells, and evaluated whether extracellular visfatin affects hepatic gluconeogenesis via an NAD+-SIRT1-dependent pathway. Treatment with visfatin significantly increased glucose production and the mRNA expression and protein levels of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) in HepG2 cells in a time- and concentration-dependent manner. Knockdown of SIRT1 had no remarkable effect on the induction of gluconeogenesis by visfatin. Subsequently, we evaluated if extracellular visfatin stimulates the production of gluconeogenic enzymes through the classical protein kinase A (PKA)/cyclic AMP-responsive element (CRE)-binding protein (CREB)-dependent process. The phosphorylation of CREB and PKA increased significantly in HepG2 cells treated with visfatin. Additionally, knockdown of CREB and PKA inhibited visfatin-induced gluconeogenesis in HepG2 cells. In summary, extracellular visfatin modulates glucose production in HepG2 cells through the PKA/CREB pathway, rather than via SIRT1 signaling. © Georg Thieme Verlag KG Stuttgart · New York.

  1. Pyruvate dehydrogenase complex and nicotinamide nucleotide transhydrogenase constitute an energy-consuming redox circuit.

    PubMed

    Fisher-Wellman, Kelsey H; Lin, Chien-Te; Ryan, Terence E; Reese, Lauren R; Gilliam, Laura A A; Cathey, Brook L; Lark, Daniel S; Smith, Cody D; Muoio, Deborah M; Neufer, P Darrell

    2015-04-15

    Cellular proteins rely on reversible redox reactions to establish and maintain biological structure and function. How redox catabolic (NAD+/NADH) and anabolic (NADP+/NADPH) processes integrate during metabolism to maintain cellular redox homoeostasis, however, is unknown. The present work identifies a continuously cycling mitochondrial membrane potential (ΔΨm)-dependent redox circuit between the pyruvate dehydrogenase complex (PDHC) and nicotinamide nucleotide transhydrogenase (NNT). PDHC is shown to produce H2O2 in relation to reducing pressure within the complex. The H2O2 produced, however, is effectively masked by a continuously cycling redox circuit that links, via glutathione/thioredoxin, to NNT, which catalyses the regeneration of NADPH from NADH at the expense of ΔΨm. The net effect is an automatic fine-tuning of NNT-mediated energy expenditure to metabolic balance at the level of PDHC. In mitochondria, genetic or pharmacological disruptions in the PDHC-NNT redox circuit negate counterbalance changes in energy expenditure. At the whole animal level, mice lacking functional NNT (C57BL/6J) are characterized by lower energy-expenditure rates, consistent with their well-known susceptibility to diet-induced obesity. These findings suggest the integration of redox sensing of metabolic balance with compensatory changes in energy expenditure provides a potential mechanism by which cellular redox homoeostasis is maintained and body weight is defended during periods of positive and negative energy balance.

  2. Synergistic Effect of Hydrotrope and Surfactant on Solubility and Dissolution of Atorvastatin Calcium: Screening Factorial Design Followed by Ratio Optimization

    PubMed Central

    Patel, V. F.; Sarai, J.

    2014-01-01

    The present study was aimed at investigating the effect of hydrotrope and surfactant on poor solubility of atorvastatin calcium. Excipients screening followed by factorial design was performed to study effect of excipients and manufacturing methods on solubility of drug. Three independent factors (carrier, surfactant and manufacturing method) were evaluated at two levels using solubility as a dependant variable. Solid-state characterisation was performed using Fourier transform infrared spectroscopy and differential scanning calorimetry. Optimised complex were incorporated into orally disintegrating micro tablets and in vitro dissolution test was performed. Nicotinamide, Plasdone and sodium dodecyl sulphate were emerged as promising excipients from excipient screening. General regression analysis revealed only the type of carrier has significantly enhanced (P<0.05) the solubility of drug while other factors were found to be nonsignificant. Ratio optimisation trial revealed that drug to nicotinamide ratio is more critical in enhancing the solubility of drug (40 fold increases in solubility compared to pure drug) in comparison to drug-surfactant ratio; however the presence of surfactant deemed essential. Significantly higher rate and extent of dissolution was observed from solid dispersion complex and tablets compared to dissolution of pure drug (P<0.05). Study revealed hydrotrope and surfactant have synergistic effect on solubility and dissolution of atorvastatin calcium and this can be explored further. PMID:25593381

  3. Iron oxide/carbon black (Fe2O3/CB) composite electrode for the detection of reduced nicotinamide cofactors using an amperometric method under a low overpotential.

    PubMed

    Kim, Yang Hee; Kim, Taeho; Ryu, Ji Heon; Yoo, Young Je

    2010-01-15

    An amperometric biosensor for the detection of the reduced nicotinamide cofactors NADH and NADPH was designed, based on the electrochemical oxidation of NAD(P)H with an iron oxide/carbon black composite (Fe(2)O(3)/CB) electrode. The electrode exhibited excellent performances in that it led to a substantial decrease in the overpotential of electrochemical NADH oxidation. Iron oxide plays a significant role as a catalyst for NADH oxidation and the reaction occurs at +0.00 V (vs. Ag/AgCl). The method of the sensor construction is very simple and the sensor performed well, giving high sensitivity, high stability, and a broad detection range. The sensitivity of this system is 2.54 microA mM(-1) and the limit of detection (S/N=3) is 10 microM. A linear range was observed between 10 microM and 1000 microM of NADH (R(2)=0.993), which is preferable to that of the previous studies. The Fe(2)O(3)/CB electrode also oxidizes NADPH under the same condition and can be applied as an NADPH sensor. Moreover, when the sensor system was integrated into a dehydrogenase-based sensor system, it also showed a good sensing performance. Copyright 2009 Elsevier B.V. All rights reserved.

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

    PubMed

    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.

  5. Molecular MRI in the Earth's Magnetic Field Using Continuous Hyperpolarization of a Biomolecule in Water.

    PubMed

    Rovedo, Philipp; Knecht, Stephan; Bäumlisberger, Tim; Cremer, Anna Lena; Duckett, Simon B; Mewis, Ryan E; Green, Gary G R; Burns, Michael; Rayner, Peter J; Leibfritz, Dieter; Korvink, Jan G; Hennig, Jürgen; Pütz, Gerhard; von Elverfeldt, Dominik; Hövener, Jan-Bernd

    2016-06-30

    In this work, we illustrate a method to continuously hyperpolarize a biomolecule, nicotinamide, in water using parahydrogen and signal amplification by reversible exchange (SABRE). Building on the preparation procedure described recently by Truong et al. [ J. Phys. Chem. B , 2014 , 118 , 13882 - 13889 ], aqueous solutions of nicotinamide and an Ir-IMes catalyst were prepared for low-field NMR and MRI. The (1)H-polarization was continuously renewed and monitored by NMR experiments at 5.9 mT for more than 1000 s. The polarization achieved corresponds to that induced by a 46 T magnet (P = 1.6 × 10(-4)) or an enhancement of 10(4). The polarization persisted, although reduced, if cell culture medium (DPBS with Ca(2+) and Mg(2+)) or human cells (HL-60) were added, but was no longer observable after the addition of human blood. Using a portable MRI unit, fast (1)H-MRI was enabled by cycling the magnetic field between 5 mT and the Earth's field for hyperpolarization and imaging, respectively. A model describing the underlying spin physics was developed that revealed a polarization pattern depending on both contact time and magnetic field. Furthermore, the model predicts an opposite phase of the dihydrogen and substrate signal after one exchange, which is likely to result in the cancelation of some signal at low field.

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

    PubMed

    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.

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

    PubMed Central

    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

  8. Reactions of Charged Substrates. 5. The Solvolysis and Sodium Azide Substitution Reactions of Benzylpyridinium Ions in Deuterium Oxide.

    PubMed

    Buckley, Neil; Oppenheimer, Norman J.

    1996-10-18

    Second-order rate constants and activation values were measured for the reactions with NaN(3) of a series of 4-Y-substituted (Y = MeO, Me, H, Cl, and NO(2)) benzyl 3'-Z-substituted (Z = CN, CONH(2), H, F, Ac) pyridinium chlorides in deuterium oxide. 3'-Cyanopyridine substrates reacted much faster than nicotinamide and pyridine substrates; in the pyridine series the 4-Me, 4-H, and 4-Cl benzyl analogs did not react for up to 6 months at 96()() degrees C in 1.7 M NaN(3). The 3'-cyanopyridine substrates do not exhibit borderline kinetic behavior, but the nicotinamide substrates do. The Hammett plot is flat for the NaN(3) reaction of 3'-cyanopyridine substrates and increasingly V-shaped for the nicotinamide and pyridine substrates. The values of beta(LG) (four-point plot) for the NaN(3) reaction of the 4-MeO benzyl substrates is -1.45, which is usually interpreted as being a very "late" activated complex. Two-point Brønsted "plots" for the other benzyl derivatives and for two N-methylpyridinium ions give values of beta(LG) in the same range. The second-order rate constant and activation values for N-methyl-3'-cyanopyridinium iodide are within the same range as those for the benzyl substrates. For the hydrolysis reaction, the Hammett plot is linear for 3'-cyanopyridine substrates (rho(+) = -1.24) and flat for the nicotinamide substrates. The extent of hydrolysis of 0.005-0.05 M solutions of the 3'-cyanopyridinie substrates depended on the initial concentration of substrate, and hydrolysis was slowed significantly or stopped completely in the presence of exogenous 3-cyanopyridine. These results show that an equilibrium is established among the products for the 4-MeO, 4-Me, 4-H, and 4-Cl substrates; the 4-NO(2) substrate reacted too slowly to discern any difference. Data for the extent of hydrolysis were fitted by an equation derived assuming the equilibrium. Despite this limitation on a classic test of mechanism, the rates and rho values are consistent with direct displacement by solvent and not with a unimolecular process. These results, which are rationalized in terms of the Pross-Shaik model, suggest that there are no ion-dipole complex intermediates in the benzyl series and show that borderline kinetic behavior is a function of leaving group ability and is not necessarily related to a change in mechanism. A computational approach was used to evaluate anomalous beta(LG) values for the hydrolysis and nucleophilic substitution reactions of the methypyridinium ion substrates. It was found that neither the Nu-substrate bond lengths nor the difference in charge matched the beta(LG) values. The value of DeltaDeltaS() of -15 gibbs/mol between (4-methoxybenzyl)-3'-cyanopyridinium chloride and the corresponding dimethylsulfonium chloride in the NaN(3) reaction, which is the result of the solvation of the pyridine at the transition state and the lack of solvation of SMe(2), is used to argue that the source of NAD(+) glycohydrolase "catalysis" of NAD(+) bond cleavage is the result of desolvation of the leaving group upon binding.

  9. Progress in utilisation of graphene for electrochemical biosensors.

    PubMed

    Lawal, Abdulazeez T

    2018-05-30

    This review discusses recent graphene (GR) electrochemical biosensor for accurate detection of biomolecules, including glucose, hydrogen peroxide, dopamine, ascorbic acid, uric acid, nicotinamide adenine dinucleotide, DNA, metals and immunosensor through effective immobilization of enzymes, including glucose oxidase, horseradish peroxidase, and haemoglobin. GR-based biosensors exhibited remarkable performance with high sensitivities, wide linear detection ranges, low detection limits, and long-term stabilities. Future challenges for the field include miniaturising biosensors and simplifying mass production are discussed. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Crystal structure of the vitamin B3 transporter PnuC, a full-length SWEET homolog.

    PubMed

    Jaehme, Michael; Guskov, Albert; Slotboom, Dirk Jan

    2014-11-01

    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 not previously observed in any protein. The high symmetry of PnuC with a single NR bound in the center suggests a simple alternating-access translocation mechanism.

  11. Discovery of Novel N-Nicotinamide Methyltransferase Inhibitors to Combat Obesity-Linked Osteoarthritis and Metabolic Disease Among Veterans and Beneficiaries

    DTIC Science & Technology

    2016-10-01

    Medical Branch at Galveston Galveston, TX 77555 REPORT DATE: October 2016 TYPE OF REPORT: Annual PREPARED FOR: U.S. Army Medical Research and...SPONSOR/MONITOR’S ACRONYM(S) U.S. Army Medical Research and Materiel Command Fort Detrick, Maryland 21702-5012 11. SPONSOR/MONITOR’S REPORT NUMBER(S...testing of in silico hits 1.1. Complete project hiring Research scientists hired February 1, 2016 and February 15, 2016. Research technician hired

  12. Native fluorescence spectroscopy of blood plasma of rats with experimental diabetes: identifying fingerprints of glucose-related metabolic pathways

    NASA Astrophysics Data System (ADS)

    Shirshin, Evgeny; Cherkasova, Olga; Tikhonova, Tatiana; Berlovskaya, Elena; Priezzhev, Alexander; Fadeev, Victor

    2015-05-01

    We present the results of a native fluorescence spectroscopy study of blood plasma of rats with experimental diabetes. It was shown that the fluorescence emission band shape at 320 nm excitation is the most indicative of hyperglycemia in the blood plasma samples. We provide the interpretation of this fact based on the changes in reduced nicotinamide adenine dinucleotide phosphate concentration due to glucose-related metabolic pathways and protein fluorescent cross-linking formation following nonenzymatic glycation.

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

    PubMed

    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.

  14. Induced Fit and the Catalytic Mechanism of Isocitrate Dehydrogenase†

    PubMed Central

    Gonçalves, Susana; Miller, Stephen P.; Carrondo, Maria A.; Dean, Anthony M.; Matias, Pedro M.

    2012-01-01

    NADP+ dependent isocitrate dehydrogenase (IDH; EC 1.1.1.42) belongs to a large family of α-hydroxyacid oxidative β-decarboxylases that catalyze similar three-step reactions, with dehydrogenation to an oxaloacid intermediate preceding β-decarboxylation to an enol intermediate followed by tautomerization to the final α-ketone product. A comprehensive view of the induced fit needed for catalysis is revealed on comparing the first “fully closed” crystal structures of a pseudo-Michaelis complex of wild-type Escherichia coli IDH (EcoIDH) and the “fully closed” reaction product complex of the K100M mutant with previously obtained “quasi-closed” and “open” conformations. Conserved catalytic residues, binding the nicotinamide ring of NADP+ and the metal-bound substrate, move as rigid bodies during domain closure by a hinge motion that spans the central β-sheet in each monomer. Interactions established between Thr105 and Ser113, which flank the “phosphorylation loop”, and the nicotinamide mononucleotide moiety of NADP+ establish productive coenzyme binding. Electrostatic interactions of a Lys100-Leu103-Asn115-Glu336 tetrad play a pivotal role in assembling a catalytically competent active site. As predicted, Lys230* is positioned to deprotonate/reprotonate the α-hydroxyl in both reaction steps and Tyr160 moves into position to protonate C3 following β-decarboxylation. A proton relay from the catalytic triad Tyr160-Asp307-Lys230* connects the α-hydroxyl of isocitrate to the bulk solvent to complete the picture of the catalytic mechanism. PMID:22891681

  15. Mitochondrial and nuclear localization of a novel pea thioredoxin: identification of its mitochondrial target proteins.

    PubMed

    Martí, María C; Olmos, Enrique; Calvete, Juan J; Díaz, Isabel; Barranco-Medina, Sergio; Whelan, James; Lázaro, Juan J; Sevilla, Francisca; Jiménez, Ana

    2009-06-01

    Plants contain several genes encoding thioredoxins (Trxs), small proteins involved in the regulation of the activity of many enzymes through dithiol-disulfide exchange. In addition to chloroplastic and cytoplasmic Trx systems, plant mitochondria contain a reduced nicotinamide adenine dinucleotide phosphate-dependent Trx reductase and a specific Trx o, and to date, there have been no reports of a gene encoding a plant nuclear Trx. We report here the presence in pea (Pisum sativum) mitochondria and nuclei of a Trx isoform (PsTrxo1) that seems to belong to the Trx o group, although it differs from this Trx type by its absence of introns in the genomic sequence. Western-blot analysis with isolated mitochondria and nuclei, immunogold labeling, and green fluorescent protein fusion constructs all indicated that PsTrxo1 is present in both cell compartments. Moreover, the identification by tandem mass spectrometry of the native mitochondrial Trx after gel filtration using the fast-protein liquid chromatography system of highly purified mitochondria and the in vitro uptake assay into isolated mitochondria also corroborated a mitochondrial location for this protein. The recombinant PsTrxo1 protein has been shown to be reduced more effectively by the Saccharomyces cerevisiae mitochondrial Trx reductase Trr2 than by the wheat (Triticum aestivum) cytoplasmic reduced nicotinamide adenine dinucleotide phosphate-dependent Trx reductase. PsTrxo1 was able to activate alternative oxidase, and it was shown to interact with a number of mitochondrial proteins, including peroxiredoxin and enzymes mainly involved in the photorespiratory process.

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

    PubMed

    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.

  17. Comparison of oral nicotinamide adenine dinucleotide (NADH) versus conventional therapy for chronic fatigue syndrome.

    PubMed

    Santaella, María L; Font, Ivonne; Disdier, Orville M

    2004-06-01

    To compare effectiveness of oral therapy with reduced nicotinamide adenine dinucleotide (NADH) to conventional modalities of treatment in patients with chronic fatigue syndrome (CFS). CFS is a potentially disabling condition of unknown etiology. Although its clinical presentation is associated to a myriad of symptoms, fatigue is a universal and essential finding for its diagnosis. No therapeutic regimen has proven effective for this condition. A total of 31 patients fulfilling the Centers for Disease Control criteria for CFS, were randomly assigned to either NADH or nutritional supplements and psychological therapy for 24 months. A thorough medical history, physical examination and completion of a questionnaire on the severity of fatigue and other symptoms were performed each trimester of therapy. In addition, all of them underwent evaluation in terms of immunological parameters and viral antibody titers. Statistical analysis was applied to the demographic data, as well as to symptoms scores at baseline and at each trimester of therapy. The twelve patients who received NADH had a dramatic and statistically significant reduction of the mean symptom score in the first trimester (p < 0.001). However, symptom scores in the subsequent trimesters of therapy were similar in both treatment groups. Elevated IgG and Ig E antibody levels were found in a significant number of patients. Observed effectiveness of NADH over conventional treatment in the first trimester of the trial and the trend of improvement of that modality in the subsequent trimesters should be further assessed in a larger patient sample.

  18. The NAMPT/E2F2/SIRT1 axis promotes proliferation and inhibits p53-dependent apoptosis in human melanoma cells.

    PubMed

    Zhao, Hailong; Tang, Weiwei; Chen, Xiaowen; Wang, Siyu; Wang, Xianyan; Xu, Haiyan; Li, Lijuan

    2017-11-04

    Melanoma is the most common primary malignant neoplasm in adults, causing more deaths than any other skin cancer, necessitating the development of new target-based approaches. Current evidence suggests SIRT1, the mammalian nicotinamide adenine dinucleotide (NAD + )-dependent protein deacetylase, and nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting NAD + biosynthetic enzyme, together comprise a novel systemic regulatory network to play a pivotal role in cell proliferation and apoptosis. Nevertheless, how the regulation of this cofactor interfaces with signal transduction network remains poorly understood in melanoma. Here, we report NAMPT is highly expressed in melanomaassociated with poor overall survival in patients. Pharmacological and genetic inhibition of NAMPT decreased NAD + levels and melanoma cell proliferation capacity, and NAMPT knockdown induced apoptosis through the activity of the tumor suppressor p53. Next, we demonstrate NAMPT regulates the transcription factor E2F family member 2 (E2F2) in the apoptosis process. Downstream, E2F2 control the mRNA and protein levels of SIRT1. Finally, we find NAMPT mediates the apoptosis resistance of melanoma cells through NAMPT-E2F2-SIRT1 axis, more than NAD + -driven transcriptional program. Accordingly, our results demonstrated that NAMPT is a prognostic marker in melanoma, and the identificationofNAMPT-E2F2-SIRT1 pathway establishes another link between NAMPT and apoptosis events in melanoma, with therapeutic implications for this deadly cancer. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Characterization of the type 2 NADH:menaquinone oxidoreductases from Staphylococcus aureus and the bactericidal action of phenothiazines.

    PubMed

    Schurig-Briccio, Lici A; Yano, Takahiro; Rubin, Harvey; Gennis, Robert B

    2014-07-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is currently one of the principal multiple drug resistant bacterial pathogens causing serious infections, many of which are life-threatening. Consequently, new therapeutic targets are required to combat such infections. In the current work, we explore the type 2 Nicotinamide adenine dinucleotide reduced form (NADH) dehydrogenases (NDH-2s) as possible drug targets and look at the effects of phenothiazines, known to inhibit NDH-2 from Mycobacterium tuberculosis. NDH-2s are monotopic membrane proteins that catalyze the transfer of electrons from NADH via flavin adenine dinucleotide (FAD) to the quinone pool. They are required for maintaining the NADH/Nicotinamide adenine dinucleotide (NAD(+)) redox balance and contribute indirectly to the generation of proton motive force. NDH-2s are not present in mammals, but are the only form of respiratory NADH dehydrogenase in several pathogens, including S. aureus. In this work, the two putative ndh genes present in the S. aureus genome were identified, cloned and expressed, and the proteins were purified and characterized. Phenothiazines were shown to inhibit both of the S. aureus NDH-2s with half maximal inhibitory concentration (IC50) values as low as 8μM. However, evaluating the effects of phenothiazines on whole cells of S. aureus was complicated by the fact that they are also acting as uncouplers of oxidative phosphorylation. This article is part of a Special Issue entitled: 18th European Bioenergetic Conference. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Monitoring ibuprofen-nicotinamide cocrystal formation during solvent free continuous cocrystallization (SFCC) using near infrared spectroscopy as a PAT tool.

    PubMed

    Kelly, A L; Gough, T; Dhumal, R S; Halsey, S A; Paradkar, A

    2012-04-15

    The purpose of this work was to explore NIR spectroscopy as a PAT tool to monitor the formation of ibuprofen and nicotinamide cocrystals during extrusion based solvent free continuous cocrystallization (SFCC). Drug and co-former were gravimetrically fed into a heated co-rotating twin screw extruder to form cocrystals. Real-time process monitoring was performed using a high temperature NIR probe in the extruder die to assess cocrystal content and subsequently compared to off-line powder X-ray diffraction measurements. The effect of processing variables, such as temperature and mixing intensity, on the extent of cocrystal formation was investigated. NIR spectroscopy was sensitive to cocrystal formation with the appearance of new peaks and peak shifts, particularly in the 4800-5200 cm(-1) wave-number region. PXRD confirmed an increased conversion of the mixture into cocrystal with increase in barrel temperature and screw mixing intensity. A decrease in screw rotation speed also provided improved cocrystal yield due to the material experiencing longer residence times within the process. A partial least squares analysis in this region of NIR spectrum correlated well with PXRD data, providing a best fit with cocrystal conversion when a limited range of process conditions were considered, for example a single set temperature. The study suggests that NIR spectroscopy could be used to monitor cocrystal purity on an industrial scale using this continuous, solvent-free process. Copyright © 2011 Elsevier B.V. All rights reserved.

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