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Sample records for murine kynurenine aminotransferases

  1. Biochemical and Structural Properties of Mouse Kynurenine Aminotransferase III

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    Han, Q.; Robinson, H; Cai, T; Tagle, D; Li, J

    2009-01-01

    Kynurenine aminotransferase III (KAT III) has been considered to be involved in the production of mammalian brain kynurenic acid (KYNA), which plays an important role in protecting neurons from overstimulation by excitatory neurotransmitters. The enzyme was identified based on its high sequence identity with mammalian KAT I, but its activity toward kynurenine and its structural characteristics have not been established. In this study, the biochemical and structural properties of mouse KAT III (mKAT III) were determined. Specifically, mKAT III cDNA was amplified from a mouse brain cDNA library, and its recombinant protein was expressed in an insect cell protein expression system. We established that mKAT III is able to efficiently catalyze the transamination of kynurenine to KYNA and has optimum activity at relatively basic conditions of around pH 9.0 and at relatively high temperatures of 50 to 60C. In addition, mKAT III is active toward a number of other amino acids. Its activity toward kynurenine is significantly decreased in the presence of methionine, histidine, glutamine, leucine, cysteine, and 3-hydroxykynurenine. Through macromolecular crystallography, we determined the mKAT III crystal structure and its structures in complex with kynurenine and glutamine. Structural analysis revealed the overall architecture of mKAT III and its cofactor binding site and active center residues. This is the first report concerning the biochemical characteristics and crystal structures of KAT III enzymes and provides a basis toward understanding the overall physiological role of mammalian KAT III in vivo and insight into regulating the levels of endogenous KYNA through modulation of the enzyme in the mouse brain.

  2. Fragment Screening of Human Kynurenine Aminotransferase-II.

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    Jayawickrama, Gayan S; Nematollahi, Alireza; Sun, Guanchen; Church, W Bret

    2018-03-01

    Kynurenine aminotransferase-II (KAT-II) is a pyridoxal 5'-phosphate (PLP)-dependent enzyme that acts in the tryptophan metabolic pathway by catalyzing the transamination of kynurenine into kynurenic acid (KYNA). It is one of four isoforms in the KAT family, of which it is the primary homologue responsible for KYNA production in the mammalian brain. KAT-II is targeted for inhibition as KYNA is implicated in diseases such as schizophrenia, where it is found in elevated concentrations. Previously, many different approaches have been taken to develop KAT-II inhibitors, and herein fragment-based drug design (FBDD) approaches have been exploited to provide further lead compounds that can be designed into novel inhibitors. Surface plasmon resonance (SPR) was used to screen a fragment library containing 1000 compounds, of which 41 hits were identified. These hits were further evaluated with SPR, and 18 were selected for inhibition studies. From these hits, two fragments, F6037-0164 and F0037-7280, were pursued and determined to have an IC 50 of 524.5 (± 25.6) μM and 115.2 (± 4.5) μM, respectively. This strategy shows the viability of using FBDD in gleaning knowledge about KAT-II inhibition and generating leads for the production of KAT-II inhibitors.

  3. Structure Expression and Function of kynurenine Aminotransferases in Human and Rodent Brains

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    Q Han; T Cai; D Tagle; J Li

    2011-12-31

    Kynurenine aminotransferases (KATs) catalyze the synthesis of kynurenic acid (KYNA), an endogenous antagonist of N-methyl-D: -aspartate and alpha 7-nicotinic acetylcholine receptors. Abnormal KYNA levels in human brains are implicated in the pathophysiology of schizophrenia, Alzheimer's disease, and other neurological disorders. Four KATs have been reported in mammalian brains, KAT I/glutamine transaminase K/cysteine conjugate beta-lyase 1, KAT II/aminoadipate aminotransferase, KAT III/cysteine conjugate beta-lyase 2, and KAT IV/glutamic-oxaloacetic transaminase 2/mitochondrial aspartate aminotransferase. KAT II has a striking tertiary structure in N-terminal part and forms a new subgroup in fold type I aminotransferases, which has been classified as subgroup Iepsilon. Knowledge regarding KATs is vast and complex; therefore, this review is focused on recent important progress of their gene characterization, physiological and biochemical function, and structural properties. The biochemical differences of four KATs, specific enzyme activity assays, and the structural insights into the mechanism of catalysis and inhibition of these enzymes are discussed.

  4. Association of kynurenine aminotransferase II gene C401T polymorphism with immune response in patients with meningitis

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    Leib Stephen L

    2011-04-01

    Full Text Available Abstract Background The kynurenine (KYN pathway has been shown to be altered in several diseases which compromise the central nervous system (CNS including infectious diseases such as bacterial meningitis (BM. The aim of this study was to assess single nucleotide polymorphisms (SNPs in four genes of KYN pathway in patients with meningitis and their correlation with markers of immune response in BM. Methods One hundred and one individuals were enrolled in this study to investigate SNPs in the following genes: indoleamine-2,3-dioxygenase (IDO1 gene, kynureninase (KYNU gene, kynurenine aminotransferase I (CCBL1 gene, and kynurenine aminotransferase II (AADAT gene. SNP analyses were performed by primer-introduced restriction analysis-PCR (PIRA-PCR followed by RFLP. Cytokines were measured using multiplex bead assay while immunoglobulins (IG by immunodiffusion plates and NF-kappaB and c-Jun by dot blot assay. Results The variant allele of SNP AADAT+401C/T showed prevalent frequency in patients with BM. A significant decrease (p AADAT+401C/T. Furthermore, a significant (p p KYNU+715G/A was found with low frequency in the groups, and the SNPs in IDO1+434T/G, KYNU+693G/A, CCBL1+164T/C, and AADAT+650C/T had no frequency in this population. Conclusions This study is the first report of an association of SNP AADAT+401C/T with the host immune response to BM, suggesting that this SNP may affect the host ability in recruitment of leukocytes to the infection site. This finding may contribute to identifying potential targets for pharmacological intervention as adjuvant therapy for BM.

  5. Kynurenine aminotransferase in the supratentorial dura mater of the rat: effect of stimulation of the trigeminal ganglion.

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    Knyihár-Csillik, Elizabeth; Chadaide, Zoltán; Okuno, Etsuo; Krisztin-Péva, Beata; Toldi, József; Varga, Csaba; Molnár, Andor; Csillik, Bert; Vécsei, László

    2004-04-01

    Electrical stimulation of the trigeminal ganglion has been widely used as a model of nociception, characterizing migraine. This treatment is known to evoke release of neuropeptides and neurotransmitters from nerve fibers of the dura mater. On the basis of immunocytochemical investigations, we found that under normal conditions, surface membranes of Schwann cells surrounding nerve fibers in the supratentorial dura mater display kynurenine aminotransferase-immunoreaction (KAT-IR); also KAT-IR are the granules of mast cells and the cytoplasms of macrophages (histiocytes). In consequence of stimulation of the trigeminal ganglion, Schwann cells in the dura mater became conspicuously swollen while their KAT-IR decreased considerably; also KAT-IR of mast cells and macrophages decreased significantly. At the same time, nitric oxide synthase (NOS)-IR of nerve fibers in the dura mater increased, suggesting release of nitric oxide (NO), this is known to be involved in NMDA receptor activation leading to vasodilation followed by neurogenic inflammation. Because kynurenic acid (KYNA) is an antagonist of NMDA receptors, we hypothesize that KYNA and its synthesizing enzyme, KAT, may play a role in the prevention of migraine attacks.

  6. Kynurenine aminotransferase III and glutamine transaminase L are identical enzymes that have cysteine S-conjugate β-lyase activity and can transaminate L-selenomethionine.

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    Pinto, John T; Krasnikov, Boris F; Alcutt, Steven; Jones, Melanie E; Dorai, Thambi; Villar, Maria T; Artigues, Antonio; Li, Jianyong; Cooper, Arthur J L

    2014-11-07

    Three of the four kynurenine aminotransferases (KAT I, II, and IV) that synthesize kynurenic acid, a neuromodulator, are identical to glutamine transaminase K (GTK), α-aminoadipate aminotransferase, and mitochondrial aspartate aminotransferase, respectively. GTK/KAT I and aspartate aminotransferase/KAT IV possess cysteine S-conjugate β-lyase activity. The gene for the former enzyme, GTK/KAT I, is listed in mammalian genome data banks as CCBL1 (cysteine conjugate beta-lyase 1). Also listed, despite the fact that no β-lyase activity has been assigned to the encoded protein in the genome data bank, is a CCBL2 (synonym KAT III). We show that human KAT III/CCBL2 possesses cysteine S-conjugate β-lyase activity, as does mouse KAT II. Thus, depending on the nature of the substrate, all four KATs possess cysteine S-conjugate β-lyase activity. These present studies show that KAT III and glutamine transaminase L are identical enzymes. This report also shows that KAT I, II, and III differ in their ability to transaminate methyl-L-selenocysteine (MSC) and L-selenomethionine (SM) to β-methylselenopyruvate (MSP) and α-ketomethylselenobutyrate, respectively. Previous studies have identified these seleno-α-keto acids as potent histone deacetylase inhibitors. Methylselenol (CH3SeH), also purported to have chemopreventive properties, is the γ-elimination product of SM and the β-elimination product of MSC catalyzed by cystathionine γ-lyase (γ-cystathionase). KAT I, II, and III, in part, can catalyze β-elimination reactions with MSC generating CH3SeH. Thus, the anticancer efficacy of MSC and SM will depend, in part, on the endogenous expression of various KAT enzymes and cystathionine γ-lyase present in target tissue coupled with the ability of cells to synthesize in situ either CH3SeH and/or seleno-keto acid metabolites. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  7. Kynurenines in CNS disease: regulation by inflammatory cytokines

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    Campbell, Brian M.; Charych, Erik; Lee, Anna W.; Möller, Thomas

    2014-01-01

    The kynurenine pathway (KP) metabolizes the essential amino acid tryptophan and generates a number of neuroactive metabolites collectively called the kynurenines. Segregated into at least two distinct branches, often termed the “neurotoxic” and “neuroprotective” arms of the KP, they are regulated by the two enzymes kynurenine 3-monooxygenase and kynurenine aminotransferase, respectively. Interestingly, several enzymes in the pathway are under tight control of inflammatory mediators. Recent years have seen a tremendous increase in our understanding of neuroinflammation in CNS disease. This review will focus on the regulation of the KP by inflammatory mediators as it pertains to neurodegenerative and psychiatric disorders. PMID:24567701

  8. The kynurenine pathway is activated in human obesity and shifted toward kynurenine monooxygenase activation.

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    Favennec, Marie; Hennart, Benjamin; Caiazzo, Robert; Leloire, Audrey; Yengo, Loïc; Verbanck, Marie; Arredouani, Abdelilah; Marre, Michel; Pigeyre, Marie; Bessede, Alban; Guillemin, Gilles J; Chinetti, Giulia; Staels, Bart; Pattou, François; Balkau, Beverley; Allorge, Delphine; Froguel, Philippe; Poulain-Godefroy, Odile

    2015-10-01

    This study characterized the kynurenine pathway (KP) in human obesity by evaluating circulating levels of kynurenines and the expression of KP enzymes in adipose tissue. Tryptophan and KP metabolite levels were measured in serum of individuals from the D.E.S.I.R. cohort (case-cohort study: 212 diabetic, 836 randomly sampled) and in women with obesity, diabetic or normoglycemic, from the ABOS cohort (n = 100). KP enzyme gene expressions were analyzed in omental and subcutaneous adipose tissue of women from the ABOS cohort, in human primary adipocytes and in monocyte-derived macrophages. In the D.E.S.I.R. cohort, kynurenine levels were positively associated with body mass index (BMI) (P = 4.68 × 10(-19) ) and with a higher HOMA2-IR insulin resistance index (P = 6.23 × 10(-4) ). The levels of kynurenine, kynurenic acid, and quinolinic acid were associated with higher BMI (P KMO], and kynurenine aminotransferase III [CCBL2]) was increased in the omental adipose tissue of women with obesity compared to lean (P KMO that is not expressed in these cells. The expressions of IDO1, KYNU, KMO, and CCBL2 were higher in proinflammatory than in anti-inflammatory macrophages (P KMO activation. © 2015 The Obesity Society.

  9. Kynurenine pathway metabolic balance influences microglia activity: Targeting kynurenine monooxygenase to dampen neuroinflammation.

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    Garrison, Allison M; Parrott, Jennifer M; Tuñon, Arnulfo; Delgado, Jennifer; Redus, Laney; O'Connor, Jason C

    2018-08-01

    Chronic stress or inflammation increases tryptophan metabolism along the kynurenine pathway (KP), and the generation of neuroactive kynurenine metabolites contributes to subsequent depressive-like behaviors. Microglia regulate KP balance by preferentially producing oxidative metabolites, including quinolinic acid. Research has focused on the interplay between cytokines and HPA axis-derived corticosteroids in regulating microglial activity and effects of KP metabolites directly on neurons; however, the potential role that KP metabolites have directly on microglial activity is unknown. Here, murine microglia were stimulated with lipopolysaccharide(LPS). After 6 h, mRNA expression of interleukin(IL)-1β, IL-6, tumor necrosis factor(TNF)-α and inducible nitric oxide synthase(iNOS) was dose-dependently increased along with the rate-limiting enzymes for oxidative KP metabolism, indoleamine-2,3-dioxygenase(IDO)-1 and kynurenine 3-monooxygenase(KMO). By 24 h post-LPS, kynurenine and quinolinic acid in the media was elevated. Inhibiting KMO with Ro 61-8048 during LPS challenge attenuated extracellular nitrite accumulation and expression of KMO and TNF-α in response to LPS. Similarly, primary microglia isolated from KMO -/- mice exhibited a significantly reduced pro-inflammatory response to LPS compared to WT controls. To determine whether the substrate (kynurenine) or end product (quinolinic acid) of KMO-dependent metabolism modulates the LPS response, microglia were treated with increasing concentrations of L-kynurenine or quinolinic acid in combination with LPS or saline. Interestingly, quinolinic acid did not impact the microglial LPS response. However, L-kynurenine had dose-dependent inhibitory effect on the LPS response. These data are the first to show an anti-inflammatory effect of KMO inhibition on microglia during immune challenge and suggest that KP metabolic balance may play a direct role in regulating microglia activity. Published by Elsevier Ltd.

  10. Skeletal muscle PGC-1α1 modulates kynurenine metabolism and mediates resilience to stress-induced depression

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    Agudelo, Leandro Z; Femenía, Teresa; Orhan, Funda

    2014-01-01

    Depression is a debilitating condition with a profound impact on quality of life for millions of people worldwide. Physical exercise is used as a treatment strategy for many patients, but the mechanisms that underlie its beneficial effects remain unknown. Here, we describe a mechanism by which...... skeletal muscle PGC-1α1 induced by exercise training changes kynurenine metabolism and protects from stress-induced depression. Activation of the PGC-1α1-PPARα/δ pathway increases skeletal muscle expression of kynurenine aminotransferases, thus enhancing the conversion of kynurenine into kynurenic acid......, a metabolite unable to cross the blood-brain barrier. Reducing plasma kynurenine protects the brain from stress-induced changes associated with depression and renders skeletal muscle-specific PGC-1α1 transgenic mice resistant to depression induced by chronic mild stress or direct kynurenine administration...

  11. Challenges and Opportunities in the Discovery of New Therapeutics Targeting the Kynurenine Pathway.

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    Dounay, Amy B; Tuttle, Jamison B; Verhoest, Patrick R

    2015-11-25

    The kynurenine pathway is responsible for the metabolism of more than 95% of dietary tryptophan (TRP) and produces numerous bioactive metabolites. Recent studies have focused on three enzymes in this pathway: indoleamine dioxygenase (IDO1), kynurenine monooxygenase (KMO), and kynurenine aminotransferase II (KAT II). IDO1 inhibitors are currently in clinical trials for the treatment of cancer, and these agents may also have therapeutic utility in neurological disorders, including multiple sclerosis. KMO inhibitors are being investigated as potential treatments for neurodegenerative diseases, such as Huntington's and Alzheimer's diseases. KAT II inhibitors have been proposed in new therapeutic approaches toward psychiatric and cognitive disorders, including cognitive impairment associated with schizophrenia. Numerous medicinal chemistry studies are currently aimed at the design of novel, potent, and selective inhibitors for each of these enzymes. The emerging opportunities and significant challenges associated with pharmacological modulation of these enzymes will be explored in this review.

  12. Involvement of the kynurenine pathway in human glioma pathophysiology.

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    Seray Adams

    Full Text Available The kynurenine pathway (KP is the principal route of L-tryptophan (TRP catabolism leading to the production of kynurenine (KYN, the neuroprotectants, kynurenic acid (KYNA and picolinic acid (PIC, the excitotoxin, quinolinic acid (QUIN and the essential pyridine nucleotide, nicotinamide adenine dinucleotide (NAD(+. The enzymes indoleamine 2,3-dioxygenase-1 (IDO-1, indoleamine 2,3-dioxygenase-2 (IDO-2 and tryptophan 2,3-dioxygenase (TDO-2 initiate the first step of the KP. IDO-1 and TDO-2 induction in tumors are crucial mechanisms implicated to play pivotal roles in suppressing anti-tumor immunity. Here, we report the first comprehensive characterisation of the KP in 1 cultured human glioma cells and 2 plasma from patients with glioblastoma (GBM. Our data revealed that interferon-gamma (IFN-γ stimulation significantly potentiated the expression of the KP enzymes, IDO-1 IDO-2, kynureninase (KYNU, kynurenine hydroxylase (KMO and significantly down-regulated 2-amino-3-carboxymuconate semialdehyde decarboxylase (ACMSD and kynurenine aminotransferase-I (KAT-I expression in cultured human glioma cells. This significantly increased KP activity but significantly lowered the KYNA/KYN neuroprotective ratio in human cultured glioma cells. KP activation (KYN/TRP was significantly higher, whereas the concentrations of the neuroreactive KP metabolites TRP, KYNA, QUIN and PIC and the KYNA/KYN ratio were significantly lower in GBM patient plasma (n = 18 compared to controls. These results provide further evidence for the involvement of the KP in glioma pathophysiology and highlight a potential role of KP products as novel and highly attractive therapeutic targets to evaluate for the treatment of brain tumors, aimed at restoring anti-tumor immunity and reducing the capacity for malignant cells to produce NAD(+, which is necessary for energy production and DNA repair.

  13. Imbalanced Kynurenine Pathway in Schizophrenia

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    Magdalena E. Kegel

    2014-01-01

    Full Text Available Several studies suggest a role for kynurenic acid (KYNA in the pathophysiology of schizophrenia. It has been proposed that increased brain KYNA levels in schizophrenia result from a pathological shift in the kynurenine pathway toward enhanced KYNA formation, away from the other branch of the pathway leading to quinolinic acid (QUIN. Here we investigate the levels of QUIN in cerebrospinal fluid (CSF of patients with schizophrenia and healthy controls, and relate those to CSF levels of KYNA and other kynurenine metabolites from the same individuals. CSF QUIN levels from stable outpatients treated with olanzapine (n = 22 and those of controls (n = 26 were analyzed using liquid chromatography-mass spectrometry. No difference in CSF QUIN levels between patients and controls was observed (20.6 ± 1.5 nM vs. 18.2 ± 1.1 nM, P = 0.36. CSF QUIN was positively correlated to CSF kynurenine and CSF KYNA in patients but not in controls. The CSF QUIN/KYNA ratio was lower in patients than in controls ( P = 0.027. In summary, the present study offers support for an over-activated and imbalanced kynurenine pathway, favoring the production of KYNA over QUIN in patients with schizophrenia.

  14. Aspartate aminotransferase (AST) blood test

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    ... gov/ency/article/003472.htm Aspartate aminotransferase (AST) blood test To use the sharing features on this page, please enable JavaScript. The aspartate aminotransferase (AST) blood test measures the level of the enzyme AST in ...

  15. Kynurenine acid - metabolism and regulation of kynurenine pathway

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    Piotr Kozłowski

    2017-07-01

    Full Text Available Kynurenic acid (KYNA was first isolated from the dog's urine in 1853 by german chemist Justus von Liebig. KYNA probably plays an important role in the pathogenesis of many neurodegenerative and psychiatric diseases. Its elevated concentration were found in the brain (post mortem or in the cerebrospinal fluid patients  with schizophrenia, bipolar disorder, Alzheimer's disease, meningitis, autoimmune diseases, inflammatory processes and memory and learning disorders. The reduced KYNA concentration is characteristic for multiple sclerosis, Parkinson's disease, Huntington's disease and epilepsy. KYNA is an organic compound naturally occurring in nature. This amino acid belongs to the group of exogenous amino acids and can be synthesized by plants and bacteria alone. The largest amount of tryptophan about 95%is  metabolised by the kynurenine pathway. Only 1% of tryptophan supplied in the diet serves to produce serotonin in the brain. The process of regulation of KYNA synthesis in both the CNS and the periphery is complicated.

  16. Impaired kynurenine pathway metabolism in the prefrontal cortex of individuals with schizophrenia.

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    Sathyasaikumar, Korrapati V; Stachowski, Erin K; Wonodi, Ikwunga; Roberts, Rosalinda C; Rassoulpour, Arash; McMahon, Robert P; Schwarcz, Robert

    2011-11-01

    The levels of kynurenic acid (KYNA), an astrocyte-derived metabolite of the branched kynurenine pathway (KP) of tryptophan degradation and antagonist of α7 nicotinic acetylcholine and N-methyl-D-aspartate receptors, are elevated in the prefrontal cortex (PFC) of individuals with schizophrenia (SZ). Because endogenous KYNA modulates extracellular glutamate and acetylcholine levels in the PFC, these increases may be pathophysiologically significant. Using brain tissue from SZ patients and matched controls, we now measured the activity of several KP enzymes (kynurenine 3-monooxygenase [KMO], kynureninase, 3-hydroxyanthranilic acid dioxygenase [3-HAO], quinolinic acid phosphoribosyltransferase [QPRT], and kynurenine aminotransferase II [KAT II]) in the PFC, ie, Brodmann areas (BA) 9 and 10. Compared with controls, the activities of KMO (in BA 9 and 10) and 3-HAO (in BA 9) were significantly reduced in SZ, though there were no significant differences between patients and controls in kynureninase, QPRT, and KAT II. In the same samples, we also confirmed the increase in the tissue levels of KYNA in SZ. As examined in rats treated chronically with the antipsychotic drug risperidone, the observed biochemical changes were not secondary to medication. A persistent reduction in KMO activity may have a particular bearing on pathology because it may signify a shift of KP metabolism toward enhanced KYNA synthesis. The present results further support the hypothesis that the normalization of cortical KP metabolism may constitute an effective new treatment strategy in SZ.

  17. Polymorphism of Kynurenine Pathway-Related Genes, Kynurenic Acid, and Psychopathological Symptoms in HIV.

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    Douet, Vanessa; Tanizaki, Naomi; Franke, Adrian; Li, Xingnan; Chang, Linda

    2016-09-01

    HIV-infection is associated with neuroinflammation and greater psychopathological symptoms, which may be mediated by imbalances in the kynurenic pathway (KP). Two key KP enzymes that catabolize kynurenine include kynurenine-aminotransferase II (KATII), which yields antioxidative kynurenine acid [KYNA] in astrocytes, and kynurenine-3-monooxygenase (KMO), which produces neurotoxic metabolites in microglia. The relationships between polymorphisms in KMO and KATII, psychopathological symptoms, and cerebrospinal fluid (CSF) [KYNA] were evaluated in subjects with and without HIV-infection. Seventy-two HIV-positive and 72-seronegative (SN) participants were genotyped for KATII-rs1480544 and KMO-rs1053230. Although our participants were not currently diagnosed with depression or anxiety, they were assessed for psychopathological distress with Center for Epidemiologic Studies-Depression scale and Symptom Checklist-90-Revised. CSF-[KYNA] was also measured in 100 subjects (49 HIV/51 SN). HIV-participants had more psychopathological distress than SN, especially for anxiety. KATII-by-HIV interactions were found on anxiety, interpersonal sensitivity and obsessive compulsivity; KATII-C-carriers had lower scores than TT-carriers in SN but not in HIV. In contrast, the KMO-polymorphism had no influence on psychopathological symptoms in both groups. Overall, CSF-[KYNA] increased with age independently of HIV-serostatus, except KATII-TT-carriers tended to show no age-dependent variations. Therefore, the C-allele in KATII-rs1480544 appears to be protective against psychopathological distress in SN but not in HIV individuals, who had more psychopathological symptoms and likely greater neuroinflammation. The age-dependent increase in CSF-[KYNA] may reflect a compensatory response to age-related inflammation, which may be deficient in KATII-TT-carriers. Targeted treatments that decrease neuroinflammation and increase KYNA in at risk KATII-TT-carriers may reduce psychopathological symptoms

  18. Structural basis of kynurenine 3-monooxygenase inhibition.

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    Amaral, Marta; Levy, Colin; Heyes, Derren J; Lafite, Pierre; Outeiro, Tiago F; Giorgini, Flaviano; Leys, David; Scrutton, Nigel S

    2013-04-18

    Inhibition of kynurenine 3-monooxygenase (KMO), an enzyme in the eukaryotic tryptophan catabolic pathway (that is, kynurenine pathway), leads to amelioration of Huntington's-disease-relevant phenotypes in yeast, fruitfly and mouse models, as well as in a mouse model of Alzheimer's disease. KMO is a flavin adenine dinucleotide (FAD)-dependent monooxygenase and is located in the outer mitochondrial membrane where it converts l-kynurenine to 3-hydroxykynurenine. Perturbations in the levels of kynurenine pathway metabolites have been linked to the pathogenesis of a spectrum of brain disorders, as well as cancer and several peripheral inflammatory conditions. Despite the importance of KMO as a target for neurodegenerative disease, the molecular basis of KMO inhibition by available lead compounds has remained unknown. Here we report the first crystal structure of Saccharomyces cerevisiae KMO, in the free form and in complex with the tight-binding inhibitor UPF 648. UPF 648 binds close to the FAD cofactor and perturbs the local active-site structure, preventing productive binding of the substrate l-kynurenine. Functional assays and targeted mutagenesis reveal that the active-site architecture and UPF 648 binding are essentially identical in human KMO, validating the yeast KMO-UPF 648 structure as a template for structure-based drug design. This will inform the search for new KMO inhibitors that are able to cross the blood-brain barrier in targeted therapies against neurodegenerative diseases such as Huntington's, Alzheimer's and Parkinson's diseases.

  19. On the relationship between the two branches of the kynurenine pathway in the rat brain in vivo.

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    Amori, Laura; Guidetti, Paolo; Pellicciari, Roberto; Kajii, Yasushi; Schwarcz, Robert

    2009-04-01

    In the mammalian brain, kynurenine aminotransferase II (KAT II) and kynurenine 3-monooxygenase (KMO), key enzymes of the kynurenine pathway (KP) of tryptophan degradation, form the neuroactive metabolites kynurenic acid (KYNA) and 3-hydroxykynurenine (3-HK), respectively. Although physically segregated, both enzymes use the pivotal KP metabolite l-kynurenine as a substrate. We studied the functional consequences of this cellular compartmentalization in vivo using two specific tools, the KAT II inhibitor BFF 122 and the KMO inhibitor UPF 648. The acute effects of selective KAT II or KMO inhibition were studied using a radiotracing method in which the de novo synthesis of KYNA, and of 3-HK and its downstream metabolite quinolinic acid (QUIN), is monitored following an intrastriatal injection of (3)H-kynurenine. In naïve rats, intrastriatal BFF 122 decreased newly formed KYNA by 66%, without influencing 3-HK or QUIN production. Conversely, UPF 648 reduced 3-HK synthesis (by 64%) without affecting KYNA formation. Similar, selective effects of KAT II and KMO inhibition were observed when the inhibitors were applied acutely together with the excitotoxin QUIN, which impairs local KP metabolism. Somewhat different effects of KMO (but not KAT II) inhibition were obtained in rats that had received an intrastriatal QUIN injection 7 days earlier. In these neuron-depleted striata, UPF 648 not only decreased both 3-HK and QUIN production (by 77% and 66%, respectively) but also moderately raised KYNA synthesis (by 27%). These results indicate a remarkable functional segregation of the two pathway branches in the brain, boding well for the development of selective KAT II or KMO inhibitors for cognitive enhancement and neuroprotection, respectively.

  20. Altered hippocampal plasticity by prenatal kynurenine administration, kynurenine-3-monoxygenase (KMO) deletion or galantamine.

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    Forrest, C M; McNair, K; Pisar, M; Khalil, O S; Darlington, L G; Stone, T W

    2015-12-03

    Glutamate receptors sensitive to N-methyl-D-aspartate (NMDA) are involved in embryonic brain development but their activity may be modulated by the kynurenine pathway of tryptophan metabolism which includes an agonist (quinolinic acid) and an antagonist (kynurenic acid) at these receptors. Our previous work has shown that prenatal inhibition of the pathway produces abnormalities of brain development. In the present study kynurenine and probenecid (both 100mg/kg, doses known to increase kynurenic acid levels in the brain) were administered to female Wistar rats on embryonic days E14, E16 and E18 of gestation and the litter was allowed to develop to post-natal day P60. Western blotting revealed no changes in hippocampal expression of several proteins previously found to be altered by inhibition of the kynurenine pathway including the NMDA receptor subunits GluN1, GluN2A and GluN2B, as well as doublecortin, Proliferating Cell Nuclear Antigen (PCNA), sonic hedgehog and unco-ordinated (unc)-5H1 and 5H3. Mice lacking the enzyme kynurenine-3-monoxygenase (KMO) also showed no changes in hippocampal expression of several of these proteins or the 70-kDa and 100-kDa variants of Disrupted in Schizophrenia-1 (DISC1). Electrical excitability of pyramidal neurons in the CA1 region of hippocampal slices was unchanged, as was paired-pulse facilitation and inhibition. Long-term potentiation was decreased in the kynurenine-treated rats and in the KMO(-/-) mice, but galantamine reversed this effect in the presence of nicotinic receptor antagonists, consistent with evidence that it can potentiate glutamate at NMDA receptors. It is concluded that interference with the kynurenine pathway in utero can have lasting effects on brain function of the offspring, implying that the kynurenine pathway is involved in the regulation of early brain development. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. Elevated levels of interleukin 17A and kynurenine in candidemic patients, compared with levels in noncandidemic patients in the intensive care unit and those in healthy controls.

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    Krause, Robert; Zollner-Schwetz, Ines; Salzer, Helmut J F; Valentin, Thomas; Rabensteiner, Jasmin; Prüller, Florian; Raggam, Reinhard; Meinitzer, Andreas; Prattes, Jürgen; Rinner, Beate; Strohmaier, Heimo; Quehenberger, Franz; Strunk, Dirk; Heidrich, Katharina; Buzina, Walter; Hoenigl, Martin

    2015-02-01

    The interplay between Candida species and pattern recognition receptors, interleukins, kynurenine, and T cells has been studied in murine and ex vivo human studies, but data are lacking from patients with invasive fungal infections. Interleukin 17A (IL-17A) is considered an important component in host defense against Candida infections and is modulated by Candida-induced impairment of tryptophan-kynurenine metabolism. Dectin-1, Toll-like receptor 2, and Toll-like receptor 4 expression; regulatory T cell (Treg) percentages; and interleukin 6, interleukin 10, IL-17A, interleukin 22, interleukin 23, interferon γ, kynurenine, and tryptophan levels were determined in candidemic patients and compared to levels in noncandidemic patients who are in the intensive care unit (ICU) and receiving antibiotic therapy and those in healthy controls, both with and without Candida colonization. Candidemic patients had significantly higher IL-17A and kynurenine levels, compared with noncandidemic patients, including Candida-colonized ICU patients and healthy controls. Within candidemic patients, time-dependent elevation of IL-17A and kynurenine levels was detected. IL-17A areas under the curve for differentiation between patients with early candidemia and those without candidemia (ICU patients, including Candida-colonized patients, and healthy controls) were between 0.94 (95% confidence interval [CI], .89-.99) and 0.99 (95% CI, .99-1). Candidemic patients had significantly higher IL-17A and kynurenine levels, compared with noncandidemic patients. The statistically significant association between IL-17A and kynurenine levels and candidemia suggests their potential as biomarkers for anticipation of invasive candidiasis. NCT00786903. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  2. Activation of kynurenine pathway in ex vivo fibroblasts from patients with bipolar disorder or schizophrenia: cytokine challenge increases production of 3-hydroxykynurenine.

    Science.gov (United States)

    Johansson, Anne-Sofie; Owe-Larsson, Björn; Asp, Linnéa; Kocki, Tomasz; Adler, Mats; Hetta, Jerker; Gardner, Renee; Lundkvist, Gabriella B S; Urbanska, Ewa M; Karlsson, Håkan

    2013-11-01

    Accumulating data suggest a causative link between immune stimulation, disturbed metabolism of tryptophan, and pathogenesis of bipolar disorder and schizophrenia. The goal of this study was to examine the production of kynurenic acid (KYNA), 3-hydroxykynurenine (3-HK) and the expression of kynurenine pathway enzymes involved in their synthesis and metabolism in cultured skin fibroblasts obtained from patients with bipolar disorder, schizophrenia or from healthy control individuals. The assessment was performed under basal conditions or following treatment with interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, or their combinations, in cells exposed to exogenous kynurenine. In both groups of patients, the baseline production of KYNA and 3-HK was increased, as compared to control subjects. Case-treatment analyses revealed significant interactions between bipolar case status and IL-1β, IL-6, IFN-γ + TNF-α, or IFN-γ + IL-1β, as well as between schizophrenia case status and IL-1β, IFN-γ + TNF-α, or IFN-γ + IL-1β, in terms of higher 3-HK. Noteworthy, no case-treatment interactions in terms of KYNA production were found. Observed changes did not appear to correlate with the expression of genes encoding kynurenine aminotransferases (KATs), kynureninase (KYNU) or kynurenine-3-monooxygenase (KMO). The single nucleotide polymorphisms (SNPs), rs1053230 and rs2275163, in KMO influenced KYNA levels yet did not explain the case-treatment discrepancies. In conclusion, our present findings indicate the utility of skin-derived fibroblasts for kynurenines research and support the concept of kynurenine pathway alterations in bipolar disorder and schizophrenia. The increase in ratio between neurotoxic 3-HK and neuroinhibitory/neuroprotective KYNA following exposure to cytokines may account for altered neurogenesis and structural abnormalities characteristic for both diseases. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Assessing and Modulating Kynurenine Pathway Dynamics in Huntington's Disease: Focus on Kynurenine 3-Monooxygenase.

    Science.gov (United States)

    Sathyasaikumar, Korrapati V; Breda, Carlo; Schwarcz, Robert; Giorgini, Flaviano

    2018-01-01

    The link between disturbances in kynurenine pathway (KP) metabolism and Huntington's disease (HD) pathogenesis has been explored for a number of years. Several novel genetic and pharmacological tools have recently been developed to modulate key regulatory steps in the KP such as the reaction catalyzed by the enzyme kynurenine 3-monooxygenase (KMO). This insight has offered new options for exploring the mechanistic link between this metabolic pathway and HD, and provided novel opportunities for the development of candidate drug-like compounds. Here, we present an overview of the field, focusing on some novel approaches for interrogating the pathway experimentally.

  4. Kynurenine Pathway Metabolites in Humans: Disease and Healthy States

    Directory of Open Access Journals (Sweden)

    Yiquan Chen

    2009-01-01

    Full Text Available Tryptophan is an essential amino acid that can be metabolised through different pathways, a major route being the kynurenine pathway. The first enzyme of the pathway, indoleamine-2,3-dioxygenase, is strongly stimulated by inflammatory molecules, particularly interferon gamma. Thus, the kynurenine pathway is often systematically up-regulated when the immune response is activated. The biological significance is that 1 the depletion of tryptophan and generation of kynurenines play a key modulatory role in the immune response; and 2 some of the kynurenines, such as quinolinic acid, 3-hydroxykynurenine and kynurenic acid, are neuroactive. The kynurenine pathway has been demonstrated to be involved in many diseases and disorders, including Alzheimer's disease, amyotrophic lateral sclerosis, Huntington's disease, AIDS dementia complex, malaria, cancer, depression and schizophrenia, where imbalances in tryptophan and kynurenines have been found. This review compiles most of these studies and provides an overview of how the kynurenine pathway might be contributing to disease development, and the concentrations of tryptophan and kynurenines in the serum, cerebrospinal fluid and brain tissues in control and patient subjects.

  5. Plasma kynurenine and related measures in tic disorder patients

    NARCIS (Netherlands)

    Hoekstra, Pieter J.; Anderson, George M.; Troost, Pieter W.; Kallenberg, Cees G. M.; Minderaa, Ruud B.

    Objective Increased plasma kynurenine has been reported in tic disorder patients, and this observation has been suggested to be indicative of immune dysregulation. In the present study, we examined plasma levels of kynurenine and related molecules in a group of tic disorder patients. Methods Plasma

  6. Influence of convulsants on rat brain activities of alanine aminotransferase and aspartate aminotransferase

    Czech Academy of Sciences Publication Activity Database

    Netopilová, M.; Haugvicová, Renata; Kubová, Hana; Dršata, J.; Mareš, Pavel

    2001-01-01

    Roč. 26, č. 12 (2001), s. 1285-1291 ISSN 0364-3190 Institutional research plan: CEZ:AV0Z5011922 Keywords : alanine aminotransferase * aspartale aminotransferase Subject RIV: FH - Neurology Impact factor: 1.638, year: 2001

  7. Induction of indolamine 2,3-dioxygenase and kynurenine 3-monooxygenase in rat brain following a systemic inflammatory challenge: a role for IFN-gamma?

    Science.gov (United States)

    Connor, Thomas J; Starr, Neasa; O'Sullivan, Joan B; Harkin, Andrew

    2008-08-15

    Inflammation-mediated dysregulation of the kynurenine pathway has been implicated as a contributor to a number of major brain disorders. Consequently, we examined the impact of a systemic inflammatory challenge on kynurenine pathway enzyme expression in rat brain. Indoleamine 2,3-dioxygenase (IDO) expression was induced in cortex and hippocampus following systemic lipopolysaccharide (LPS) administration. Whilst IDO expression was paralleled by increased circulating interferon (IFN)-gamma concentrations, IFN-gamma expression in the brain was only modestly altered following LPS administration. In contrast, induction of IDO was associated with increased central tumour necrosis factor (TNF)-alpha and interleukin (IL)-6 expression. Similarly, in cultured glial cells LPS-induced IDO expression was accompanied by increased TNF-alpha and IL-6 expression, whereas IFN-gamma was not detectable. These findings indicate that IFN-gamma is not required for LPS-induced IDO expression in brain. A robust increase in kynurenine-3-monooxygenase (KMO) expression was observed in rat brain 24h post LPS, without any change in kynurenine aminotransferase II (KAT II) expression. In addition, we report that constitutive expression of KAT II is approximately 8-fold higher than KMO in cortex and 20-fold higher in hippocampus. Similarly, in glial cells constitutive expression of KAT II was approximately 16-fold higher than KMO, and expression of KMO but not KAT II was induced by LPS. These data are the first to demonstrate that a systemic inflammatory challenge stimulates KMO expression in brain; a situation that is likely to favour kynurenine metabolism in a neurotoxic direction. However, our observation that expression of KAT II is much higher than KMO in rat brain is likely to counteract potential neurotoxicity that could arise from KMO induction following an acute inflammation.

  8. The L-kynurenine signalling pathway in trigeminal pain processing

    DEFF Research Database (Denmark)

    Guo, Song; Vecsei, L; Ashina, Messoud

    2011-01-01

    In recent years the kynurenine family of compounds, metabolites of tryptophan, has become an area of intensive research because of its neuroactive properties. Two metabolites of this family have become of interest in relation to migraine and pain processing....

  9. The L-kynurenine signalling pathway in trigeminal pain processing

    DEFF Research Database (Denmark)

    Guo, Song; Vecsei, L; Ashina, Messoud

    2011-01-01

    In recent years the kynurenine family of compounds, metabolites of tryptophan, has become an area of intensive research because of its neuroactive properties. Two metabolites of this family have become of interest in relation to migraine and pain processing.......In recent years the kynurenine family of compounds, metabolites of tryptophan, has become an area of intensive research because of its neuroactive properties. Two metabolites of this family have become of interest in relation to migraine and pain processing....

  10. Immunohistochemical Studies of the Kynurenine Pathway in Morphea

    Directory of Open Access Journals (Sweden)

    Rowland Noakes

    2013-01-01

    Full Text Available Cutaneous sclerosis, resembling that seen in subcutaneous morphea, is a feature of eosinophilic fasciitis and eosinophilia-myalgia syndrome, two conditions in which the kynurenine pathway is known to be activated. To investigate the possibility of activation of the kynurenine pathway in morphea, skin biopsies were taken from involved and non-involved sites in a series of three patients with morphea. Immunohistochemical stains for quinolinic acid and indoleamine 2,3-dioxygenase (IDO were performed.

  11. Immunohistochemical Studies of the Kynurenine Pathway in Morphea

    OpenAIRE

    Noakes, Rowland; Mellick, Nick

    2013-01-01

    Cutaneous sclerosis, resembling that seen in subcutaneous morphea, is a feature of eosinophilic fasciitis and eosinophilia-myalgia syndrome, two conditions in which the kynurenine pathway is known to be activated. To investigate the possibility of activation of the kynurenine pathway in morphea, skin biopsies were taken from involved and non-involved sites in a series of three patients with morphea. Immunohistochemical stains for quinolinic acid and indoleamine 2,3-dioxygenase (IDO) were perf...

  12. Substrate and inhibitor specificity of kynurenine monooxygenase from Cytophaga hutchinsonii.

    Science.gov (United States)

    Phillips, Robert S; Anderson, Andrew D; Gentry, Harvey G; Güner, Osman F; Bowen, J Phillip

    2017-04-15

    Kynurenine monooxygenase (KMO) is a potential drug target for treatment of neurodegenerative disorders such as Huntington's and Alzheimer's diseases. We have evaluated substituted kynurenines as substrates or inhibitors of KMO from Cytophaga hutchinsonii. Kynurenines substituted with a halogen at the 5-position are excellent substrates, with values of k cat and k cat /K m comparable to or higher than kynurenine. However, kynurenines substituted in the 3-position are competitive inhibitors, with K I values lower than the K m for kynurenine. Bromination also enhances inhibition, and 3,5-dibromokynurenine is a potent competitive inhibitor with a K I value of 1.5μM. A pharmacophore model of KMO was developed, and predicted that 3,4-dichlorohippuric acid would be an inhibitor. The K I for this compound was found to be 34μM, thus validating the pharmacophore model. We are using these results and our model to design more potent inhibitors of KMO. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Kynurenine pathway metabolites and enzymes involved in redox reactions.

    Science.gov (United States)

    González Esquivel, D; Ramírez-Ortega, D; Pineda, B; Castro, N; Ríos, C; Pérez de la Cruz, V

    2017-01-01

    Oxido-reduction reactions are a fundamental part of the life due to support many vital biological processes as cellular respiration and glucose oxidation. In the redox reactions, one substance transfers one or more electrons to another substance. An important electron carrier is the coenzyme NAD + , which is involved in many metabolic pathways. De novo biosynthesis of NAD + is through the kynurenine pathway, the major route of tryptophan catabolism, which is sensitive to redox environment and produces metabolites with redox capacity, able to alter biological functions that are controlled by redox-responsive signaling pathways. Kynurenine pathway metabolites have been implicated in the physiology process and in the physiopathology of many diseases; processes that also share others factors as dysregulation of calcium homeostasis, mitochondrial dysfunction, oxidative stress, inflammation and cell death, which impact the redox environment. This review examines in detail the available evidence in which kynurenine pathway metabolites participate in redox reactions and their effect on cellular redox homeostasis, since the knowledge of the main factors and mechanisms that lead to cell death in many neurodegenative disorders and other pathologies, such as mitochondrial dysfunction, oxidative stress and kynurenines imbalance, will allow to develop therapies using them as targets. This article is part of the Special Issue entitled 'The Kynurenine Pathway in Health and Disease'. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Tryptophan and kynurenine determination in human hair by liquid chromatography.

    Science.gov (United States)

    Dario, Michelli F; Freire, Thamires Batello; Pinto, Claudinéia Aparecida Sales de Oliveira; Prado, María Segunda Aurora; Baby, André R; Velasco, Maria Valéria R

    2017-10-15

    Tryptophan, an amino acid found in hair proteinaceous structure is used as a marker of hair photodegradation. Also, protein loss caused by several chemical/physical treatments can be inferred by tryptophan quantification. Kynurenine is a photo-oxidation product of tryptophan, expected to be detected when hair is exposed mainly to UVB (290-320nm) radiation range. Tryptophan from hair is usually quantified directly as a solid or after alkaline hydrolysis, spectrofluorimetrically. However, these types of measure are not sufficiently specific and present several interfering substances. Thus, this work aimed to propose a quantification method for both tryptophan and kynurenine in hair samples, after alkali hydrolysis process, by using high-performance liquid chromatography (HPLC) with fluorimetric and UV detection. The tryptophan and kynurenine quantification method was developed and validated. Black, white, bleached and dyed (blond and auburn) hair tresses were used in this study. Tryptophan and kynurenine were separated within ∼9min by HPLC. Both black and white virgin hair samples presented similar concentrations of tryptophan, while bleaching caused a reduction in the tryptophan content as well as dyeing process. Unexpectedly, UV/vis radiation did not promote significantly the conversion of tryptophan into its photo-oxidation product and consequently, kynurenine was not detected. Thus, this works presented an acceptable method for quantification of tryptophan and its photooxidation metabolite kynurenine in hair samples. Also, the results indicated that bleaching and dyeing processes promoted protein/amino acids loss but tryptophan is not extensively degraded in human hair by solar radiation. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Kynurenine pathway in psychosis: evidence of increased tryptophan degradation.

    LENUS (Irish Health Repository)

    Barry, Sandra

    2009-05-01

    The kynurenine pathway of tryptophan degradation may serve to integrate disparate abnormalities heretofore identified in research aiming to elucidate the complex aetiopathogenesis of psychotic disorders. Post-mortem brain tissue studies have reported elevated kynurenine and kynurenic acid in the frontal cortex and upregulation of the first step of the pathway in the anterior cingulate cortex of individuals with schizophrenia. In this study, we examined kynurenine pathway activity by measuring tryptophan breakdown, a number of pathway metabolites and interferon gamma (IFN-gamma), which is the preferential activator of the first-step enzyme, indoleamine dioxygenase (IDO), in the plasma of patients with major psychotic disorder. Plasma tryptophan, kynurenine pathway metabolites were measured using high-performance liquid chromatography (HPLC) in 34 patients with a diagnosis on the psychotic spectrum (schizophrenia or schizoaffective disorder) and in 36 healthy control subjects. IFN-gamma was measured using enzyme-linked immunosorbent assay (ELISA). The mean tryptophan breakdown index (kynurenine\\/tryptophan) was significantly higher in the patient group compared with controls (P < 0.05). IFN-gamma measures did not differ between groups (P = 0.23). No relationship was found between measures of psychopathology, symptom severity and activity in the first step in the pathway. A modest correlation was established between the tryptophan breakdown index and illness duration. These results provide evidence for kynurenine pathway upregulation, specifically involving the first enzymatic step, in patients with major psychotic disorder. Increased tryptophan degradation in psychoses may have potential consequences for the treatment of these disorders by informing the development of novel therapeutic compounds.

  16. Increased liver alkaline phosphatase and aminotransferase ...

    African Journals Online (AJOL)

    The effect of daily, oral administration of ethanolic extract of Khaya senegalensis stem bark (2mg/kg body weight) for 18days on the alkaline phosphatase, aspartate and alanine aminotransferase activities of rat liver and serum were investigated. Compared with the control, the activities of liver alkaline phosphatase (ALP), ...

  17. The concentration of kynurenine in rat model of asthma.

    Directory of Open Access Journals (Sweden)

    Barbara Mroczko

    2008-06-01

    Full Text Available Asthma is a chronic inflammatory disease that involves the immune system activation. Evidence is accumulating about the role of kynurenine pathway in the immune system regulation. The kynurenine pathway includes several metabolites of tryptophan, among others kynurenine (KYN. To study the immunological system regulation in asthma a simple and sensitive models of asthma are required. In the present study we induced rat model of asthma using ovalbumin (OVA sensitization followed by challenge with OVA. The development of asthma has been confirmed by plasma total IgE measurement and the histological examination. The concentration of KYN has been determined in plasma, lungs and liver by high-performance liquid chromatography (HPLC. In OVA sensitized rats the concentration of total IgE was statistically significantly increased as compared to VEH sensitized control groups (437.6 +/- 97.7 kU/l vs 159.2 +/- 22.7 kU/l, respectively; p< 0.01. In asthmatic animals, the number of eosinophils, neutrophils and mast cells increased considerably, and epithelial lesion and the increase in airway epithelium goblet cells and edema of bronchial mucosa were present. We did not observe any significant changes in the concentration of KYN in plasma, lungs or liver between studied groups. In conclusion, the concentration of KYN remains unchanged in asthmatic animals as compared to control groups. Further studies using rat model of asthma are warranted to establish the role of kynurenine pathway regulation in asthma.

  18. Kynurenine 3-Monooxygenase: An Influential Mediator of Neuropathology.

    Science.gov (United States)

    Parrott, Jennifer M; O'Connor, Jason C

    2015-01-01

    Mounting evidence demonstrates that kynurenine metabolism may play an important pathogenic role in the development of multiple neurological and neuropsychiatric disorders. The kynurenine pathway consists of two functionally distinct branches that generate both neuroactive and oxidatively reactive metabolites. In the brain, the rate-limiting enzyme for one of these branches, kynurenine 3-monooxygenase (KMO), is predominantly expressed in microglia and has emerged as a pivotal point of metabolic regulation. KMO substrate and expression levels are upregulated by pro-inflammatory cytokines and altered by functional genetic mutations. Increased KMO metabolism results in the formation of metabolites that activate glutamate receptors and elevate oxidative stress, while recent evidence has revealed neurodevelopmental consequences of reduced KMO activity. Together, the evidence suggests that KMO is positioned at a critical metabolic junction to influence the development or trajectory of a myriad of neurological diseases. Understanding the mechanism(s) by which alterations in KMO activity are able to impair neuronal function, and viability will enhance our knowledge of related disease pathology and provide insight into novel therapeutic opportunities. This review will discuss the influence of KMO on brain kynurenine metabolism and the current understanding of molecular mechanisms by which altered KMO activity may contribute to neurodevelopment, neurodegenerative, and neuropsychiatric diseases.

  19. Kynurenine 3-monooxygenase: an influential mediator of neuropathology

    Directory of Open Access Journals (Sweden)

    Jennifer M Parrott

    2015-08-01

    Full Text Available Mounting evidence demonstrates that kynurenine metabolism may play an important pathogenic role in the development of multiple neurological and neuropsychiatric disorders. The kynurenine pathway consists of two functionally distinct branches that generate both neuroactive and oxidatively reactive metabolites. In the brain, the rate-limiting enzyme for one of these branches, kynurenine 3-monooxygenase (KMO, is predominantly expressed in microglia and has emerged as a pivotal point of metabolic regulation. KMO substrate and expression levels are up-regulated by pro-inflammatory cytokines and altered by functional genetic mutations. Increased KMO metabolism results in the formation of metabolites that activate glutamate receptors and elevate oxidative stress, while recent evidence has revealed neurodevelopmental consequences of reduced KMO activity. Together, the evidence suggests that KMO is positioned at a critical metabolic junction to influence the development or trajectory of a myriad of neurological diseases. Understanding the mechanism(s by which alterations in KMO activity are able to impair neuronal function and viability will enhance our knowledge of related disease pathology and provide insight into novel therapeutic opportunities. This review will discuss the influence of KMO on brain kynurenine metabolism and the current understanding of molecular mechanisms by which altered KMO activity may contribute to neurodevelopment, neurodegenerative and neuropsychiatric diseases.

  20. Serine:glyoxylate aminotransferase mutant of barley

    International Nuclear Information System (INIS)

    Blackwell, R.; Murray, A.; Joy, K.; Lea, P.

    1987-01-01

    A photorespiratory mutant of barley (LaPr 85/84), deficient in both of the major peaks of serine:glyoxylate aminotransferase activity detected in the wild type, also lacks serine:pyruvate and asparagine:glyoxylate aminotransferase activities. Genetic analysis of the mutation demonstrated that these three activities are all carried on the same enzyme. The mutant, when placed in air, accumulated a large pool of serine, showed the expected rate (50%) of ammonia release during photorespiration but produced CO 2 at twice the wild type rate when it was fed [ 14 C] glyoxylate. Compared with the wild type, LaPr 85/84 exhibited abnormal transient changes in chlorophyll a fluorescence when the CO 2 concentration of the air was altered, indicating that the rates of the fluorescence quenching mechanisms were affected in vivo by the lack of this enzyme

  1. Alanine Aminotransferase, ?-Glutamyltransferase, and Incident Diabetes

    OpenAIRE

    Fraser, Abigail; Harris, Ross; Sattar, Naveed; Ebrahim, Shah; Davey Smith, George; Lawlor, Debbie A.

    2009-01-01

    OBJECTIVE: To estimate and compare associations of alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT) with incident diabetes. RESEARCH DESIGN AND METHODS: ALT and GGT were studied as determinants of diabetes in the British Women's Heart and Health Study, a cohort of 4,286 women 60-79 years old (median follow-up 7.3 years). A systematic review and a meta-analysis of 21 prospective, population-based studies of ultrasonography, which diagnosed nonalcoholic fatty liver disease (NA...

  2. [Association of kynurenine-3-monooxygenase gene with schizophrenia].

    Science.gov (United States)

    Golimbet, V E; Lezheiko, T V; Alfimova, M V; Abramova, L I; Kondrat'ev, N V

    2014-06-01

    Neurotoxic products produced during tryptophan metabolism via the kynurenine pathway could be involved in schizophrenia pathogenesis. It has been shown that kynurenine-3-monooxygenase (KMO) is indirectly involved in these products' formation. KMO polymorphic loci rs2275163 (C/T) and rs1053230 (A/G) were examined in 187 schizophrenia patients and 229 healthy subjects. A genetic combination of allele T and genotype GG was observed more often in a patient group compared with healthy controls (p = 0.003, OR 2.0 (95% CI 1.2-2.9). In the latter group, this combination was associated with schizophrenia endophenotype (p = 0.04), which manifested in a higher expression of schizotypal personality traits assessed using the MMPI test.

  3. Bacterial expression of human kynurenine 3-monooxygenase: solubility, activity, purification.

    Science.gov (United States)

    Wilson, K; Mole, D J; Binnie, M; Homer, N Z M; Zheng, X; Yard, B A; Iredale, J P; Auer, M; Webster, S P

    2014-03-01

    Kynurenine 3-monooxygenase (KMO) is an enzyme central to the kynurenine pathway of tryptophan metabolism. KMO has been implicated as a therapeutic target in several disease states, including Huntington's disease. Recombinant human KMO protein production is challenging due to the presence of transmembrane domains, which localise KMO to the outer mitochondrial membrane and render KMO insoluble in many in vitro expression systems. Efficient bacterial expression of human KMO would accelerate drug development of KMO inhibitors but until now this has not been achieved. Here we report the first successful bacterial (Escherichia coli) expression of active FLAG™-tagged human KMO enzyme expressed in the soluble fraction and progress towards its purification. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

  4. Bacterial expression of human kynurenine 3-monooxygenase: Solubility, activity, purification☆

    Science.gov (United States)

    Wilson, K.; Mole, D.J.; Binnie, M.; Homer, N.Z.M.; Zheng, X.; Yard, B.A.; Iredale, J.P.; Auer, M.; Webster, S.P.

    2014-01-01

    Kynurenine 3-monooxygenase (KMO) is an enzyme central to the kynurenine pathway of tryptophan metabolism. KMO has been implicated as a therapeutic target in several disease states, including Huntington’s disease. Recombinant human KMO protein production is challenging due to the presence of transmembrane domains, which localise KMO to the outer mitochondrial membrane and render KMO insoluble in many in vitro expression systems. Efficient bacterial expression of human KMO would accelerate drug development of KMO inhibitors but until now this has not been achieved. Here we report the first successful bacterial (Escherichia coli) expression of active FLAG™-tagged human KMO enzyme expressed in the soluble fraction and progress towards its purification. PMID:24316190

  5. Kynurenine-3-monooxygenase: a review of structure, mechanism, and inhibitors.

    Science.gov (United States)

    Smith, Jason R; Jamie, Joanne F; Guillemin, Gilles J

    2016-02-01

    Kynurenine monooxygenase (KMO) is an enzyme of the kynurenine (Kyn) pathway (KP), which is the major catabolic route of tryptophan. Kyn represents a branch point of the KP, being converted into the neurotoxin 3-hydroxykynurenine via KMO, neuroprotectant kynurenic acid, and anthranilic acid. As a result of this branch point, KMO is an attractive drug target for several neurodegenerative and/or neuroinflammatory diseases, especially Huntington's (HD), Alzheimer's (AD), and Parkinson's (PD) diseases. Although a neurological target, administration of KMO inhibitors in the periphery has demonstrated promising pharmacological results. In light of a recent crystal structure release and reports of preclinical candidates, here we provide a concise yet comprehensive update on the current state of research into the enzymology of KMO and related drug discovery efforts, highlighting areas where further work is required. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Antioxidant Properties of Kynurenines: Density Functional Theory Calculations

    Science.gov (United States)

    2016-01-01

    Kynurenines, the main products of tryptophan catabolism, possess both prooxidant and anioxidant effects. Having multiple neuroactive properties, kynurenines are implicated in the development of neurological and cognitive disorders, such as Alzheimer's, Parkinson's, and Huntington's diseases. Autoxidation of 3-hydroxykynurenine (3HOK) and its derivatives, 3-hydroxyanthranilic acid (3HAA) and xanthommatin (XAN), leads to the hyperproduction of reactive oxygen species (ROS) which damage cell structures. At the same time, 3HOK and 3HAA have been shown to be powerful ROS scavengers. Their ability to quench free radicals is believed to result from the presence of the aromatic hydroxyl group which is able to easily abstract an electron and H-atom. In this study, the redox properties for kynurenines and several natural and synthetic antioxidants have been calculated at different levels of density functional theory in the gas phase and water solution. Hydroxyl bond dissociation enthalpy (BDE) and ionization potential (IP) for 3HOK and 3HAA appear to be lower than for xanthurenic acid (XAA), several phenolic antioxidants, and ascorbic acid. BDE and IP for the compounds with aromatic hydroxyl group are lower than for their precursors without hydroxyl group. The reaction rate for H donation to *O-atom of phenoxyl radical (Ph-O*) and methyl peroxy radical (Met-OO*) decreases in the following rankings: 3HOK ~ 3HAA > XAAOXO > XAAENOL. The enthalpy absolute value for Met-OO* addition to the aromatic ring of the antioxidant radical increases in the following rankings: 3HAA* < 3HOK* < XAAOXO* < XAAENOL*. Thus, the high free radical scavenging activity of 3HAA and 3HOK can be explained by the easiness of H-atom abstraction and transfer to O-atom of the free radical, rather than by Met-OO* addition to the kynurenine radical. PMID:27861556

  7. Kynurenine 3-monooxygenase inhibition in blood ameliorates neurodegeneration

    Science.gov (United States)

    Zwilling, Daniel; Huang, Shao-Yi; Sathyasaikumar, Korrapati V.; Notarangelo, Francesca M.; Guidetti, Paolo; Wu, Hui-Qiu; Lee, Jason; Truong, Jennifer; Andrews-Zwilling, Yaisa; Hsieh, Eric W.; Louie, Jamie Y.; Wu, Tiffany; Scearce-Levie, Kimberly; Patrick, Christina; Adame, Anthony; Giorgini, Flaviano; Moussaoui, Saliha; Laue, Grit; Rassoulpour, Arash; Flik, Gunnar; Huang, Yadong; Muchowski, Joseph M.; Masliah, Eliezer; Schwarcz, Robert; Muchowski, Paul J.

    2011-01-01

    SUMMARY Metabolites in the kynurenine pathway of tryptophan degradation are thought to play an important role in neurodegenerative disorders such as Alzheimer’s disease and Huntington’s disease. Metabolites that cause glutamate receptor-mediated excitotoxicity and free radical formation are elevated in the blood and vulnerable brain regions in these diseases, while levels of the neuroprotective metabolite kynurenic acid are often decreased. Here we describe the synthesis and characterization of JM6, a novel small-molecule pro-drug inhibitor of kynurenine 3-monooxygenase (KMO). JM6 raises kynurenic acid and reduces extracellular glutamate in the brain after chronic oral administration by inhibiting KMO in blood. In a transgenic mouse model of Alzheimer’s disease, JM6 prevented spatial memory deficits, anxiety-related behavior, and synaptic loss. JM6 also extended life span, prevented synaptic loss, and decreased microglial activation in a mouse model of Huntington’s disease. These findings support a critical link between blood cells and neurodegeneration that is mediated by KMO and the kynurenine pathway. PMID:21640374

  8. Effect of Orthodontic Tooth Movement on Salivary Aspartate Aminotransferase Activity

    Directory of Open Access Journals (Sweden)

    Steiven Adhitya

    2013-07-01

    Full Text Available 72 1024x768 Aspartate aminotransferase is one of biological indicator in gingival crevicular fluid (CGF. Force orthodontic application could increase activity of aspartate aminotransferase in CGF. However, the increase activity of aspartate aminotransferase in saliva due to orthodontic force and its correlation between aspartate aminotransferase activity and tooth movement remains unclear. Objectives: To evaluate application orthodontic force on the aspartate aminotransferase activity in saliva based on the duration of force and finding correlation between tooth movement and aspartate aminotransferase activity. Methods: Twenty saliva samples collected before extraction of first premolar, at the time of force application for canine retraction and after force application. The canines retraction used 100 grams of interrupted force (module chain for thirty days. The collection of saliva and the measurement of tooth movement were carried out 1 day, 7 days, 14 days, 21 days, and 28 days after force application. The measurement of aspartate aminotransferase activity in saliva was done using spectrophotometer. Results: Application of orthodontic force influences the salivary aspartate aminotransferase activity (F=25.290, p=0.000. Furthermore, tooth movement correlated with aspartate aminotransferase activity (F=0.429, p=0.000. Conclusion: Aspartate aminotransferase activity could be used as tooth movement indicator that related to the duration of force application.DOI : 10.14693/jdi.v20i1.128

  9. Targeted deletion of kynurenine 3-monooxygenase in mice: a new tool for studying kynurenine pathway metabolism in periphery and brain.

    Science.gov (United States)

    Giorgini, Flaviano; Huang, Shao-Yi; Sathyasaikumar, Korrapati V; Notarangelo, Francesca M; Thomas, Marian A R; Tararina, Margarita; Wu, Hui-Qiu; Schwarcz, Robert; Muchowski, Paul J

    2013-12-20

    Kynurenine 3-monooxygenase (KMO), a pivotal enzyme in the kynurenine pathway (KP) of tryptophan degradation, has been suggested to play a major role in physiological and pathological events involving bioactive KP metabolites. To explore this role in greater detail, we generated mice with a targeted genetic disruption of Kmo and present here the first biochemical and neurochemical characterization of these mutant animals. Kmo(-/-) mice lacked KMO activity but showed no obvious abnormalities in the activity of four additional KP enzymes tested. As expected, Kmo(-/-) mice showed substantial reductions in the levels of its enzymatic product, 3-hydroxykynurenine, in liver, brain, and plasma. Compared with wild-type animals, the levels of the downstream metabolite quinolinic acid were also greatly decreased in liver and plasma of the mutant mice but surprisingly were only slightly reduced (by ∼20%) in the brain. The levels of three other KP metabolites: kynurenine, kynurenic acid, and anthranilic acid, were substantially, but differentially, elevated in the liver, brain, and plasma of Kmo(-/-) mice, whereas the liver and brain content of the major end product of the enzymatic cascade, NAD(+), did not differ between Kmo(-/-) and wild-type animals. When assessed by in vivo microdialysis, extracellular kynurenic acid levels were found to be significantly elevated in the brains of Kmo(-/-) mice. Taken together, these results provide further evidence that KMO plays a key regulatory role in the KP and indicate that Kmo(-/-) mice will be useful for studying tissue-specific functions of individual KP metabolites in health and disease.

  10. Targeted Deletion of Kynurenine 3-Monooxygenase in Mice

    Science.gov (United States)

    Giorgini, Flaviano; Huang, Shao-Yi; Sathyasaikumar, Korrapati V.; Notarangelo, Francesca M.; Thomas, Marian A. R.; Tararina, Margarita; Wu, Hui-Qiu; Schwarcz, Robert; Muchowski, Paul J.

    2013-01-01

    Kynurenine 3-monooxygenase (KMO), a pivotal enzyme in the kynurenine pathway (KP) of tryptophan degradation, has been suggested to play a major role in physiological and pathological events involving bioactive KP metabolites. To explore this role in greater detail, we generated mice with a targeted genetic disruption of Kmo and present here the first biochemical and neurochemical characterization of these mutant animals. Kmo−/− mice lacked KMO activity but showed no obvious abnormalities in the activity of four additional KP enzymes tested. As expected, Kmo−/− mice showed substantial reductions in the levels of its enzymatic product, 3-hydroxykynurenine, in liver, brain, and plasma. Compared with wild-type animals, the levels of the downstream metabolite quinolinic acid were also greatly decreased in liver and plasma of the mutant mice but surprisingly were only slightly reduced (by ∼20%) in the brain. The levels of three other KP metabolites: kynurenine, kynurenic acid, and anthranilic acid, were substantially, but differentially, elevated in the liver, brain, and plasma of Kmo−/− mice, whereas the liver and brain content of the major end product of the enzymatic cascade, NAD+, did not differ between Kmo−/− and wild-type animals. When assessed by in vivo microdialysis, extracellular kynurenic acid levels were found to be significantly elevated in the brains of Kmo−/− mice. Taken together, these results provide further evidence that KMO plays a key regulatory role in the KP and indicate that Kmo−/− mice will be useful for studying tissue-specific functions of individual KP metabolites in health and disease. PMID:24189070

  11. IL-22 and IDO1 Affect Immunity and Tolerance to Murine and Human Vaginal Candidiasis

    Science.gov (United States)

    De Luca, Antonella; Carvalho, Agostinho; Cunha, Cristina; Iannitti, Rossana G.; Pitzurra, Lucia; Giovannini, Gloria; Mencacci, Antonella; Bartolommei, Lorenzo; Moretti, Silvia; Massi-Benedetti, Cristina; Fuchs, Dietmar; De Bernardis, Flavia; Puccetti, Paolo; Romani, Luigina

    2013-01-01

    The ability to tolerate Candida albicans, a human commensal of the gastrointestinal tract and vagina, implicates that host defense mechanisms of resistance and tolerance cooperate to limit fungal burden and inflammation at the different body sites. We evaluated resistance and tolerance to the fungus in experimental and human vulvovaginal candidiasis (VVC) as well as in recurrent VVC (RVVC). Resistance and tolerance mechanisms were both activated in murine VVC, involving IL-22 and IL-10-producing regulatory T cells, respectively, with a major contribution by the enzyme indoleamine 2,3-dioxygenase 1 (IDO1). IDO1 was responsible for the production of tolerogenic kynurenines, such that replacement therapy with kynurenines restored immunoprotection to VVC. In humans, two functional genetic variants in IL22 and IDO1 genes were found to be associated with heightened resistance to RVVC, and they correlated with increased local expression of IL-22, IDO1 and kynurenines. Thus, IL-22 and IDO1 are crucial in balancing resistance with tolerance to Candida, their deficiencies are risk factors for RVVC, and targeting tolerance via therapeutic kynurenines may benefit patients with RVVC. PMID:23853597

  12. Successful metformin treatment of insulin resistance is associated with down-regulation of the kynurenine pathway

    International Nuclear Information System (INIS)

    Muzik, Otto; Burghardt, Paul; Yi, Zhengping; Kumar, Ajay; Seyoum, Berhane

    2017-01-01

    Context: An extensive body of literature indicates a relationship between insulin resistance and the up-regulation of the kynurenine pathway, i.e. the preferential conversion of tryptophan to kynurenine, with subsequent overproduction of diabetogenic downstream metabolites, such as kynurenic acid. Case description: We have measured the concentration of kynurenine pathway metabolites (kynurenines) in the brain and pancreas of two young (27 and 28 yrs) insulin resistant, normoglycemic subjects (M-values 2 and 4 mg/kg/min, respectively) using quantitative C-11-alpha-methyl-tryptophan PET/CT imaging. Both subjects underwent a preventive 12-week metformin treatment regimen (500 mg daily) prior to the PET/CT study. Whereas treatment was successful in one of the subject (M-value increased from 2 to 12 mg/kg/min), response was poor in the other subjects (M-value changed from 4 to 5 mg/kg/min). Brain and pancreas concentrations of kynurenines observed in the responder were similar to that in a healthy control subject, whereas kynurenines determined in the non-responder were about 25% higher and similar to those found in a severely insulin resistant patient. Consistent with this outcome, M-values were negatively correlated with both kynurenic acid levels (R 2  = 0.68, p = 0.09) as well as with the kynurenine to tryptophan ratio (R 2  = 0.63, p = 0.11). Conclusion: The data indicates that kynurenine pathway metabolites are increased in subjects with insulin resistance prior to overt manifestation of hyperglycemia. Moreover, successful metformin treatment leads to a normalization of tryptophan metabolism, most likely as a result of decreased contribution from the kynurenine metabolic pathway.

  13. Kynurenine pathway changes in late-life depression.

    Science.gov (United States)

    Wu, Yujie; Zhong, Xiaomei; Mai, Naikeng; Wen, Yuguan; Shang, Dewei; Hu, Lijun; Chen, Ben; Zhang, Min; Ning, Yuping

    2018-08-01

    Kynurenine pathway (KP) activation is associated with several neuropsychiatric diseases, including major depression disorder (MDD). Although several investigations have been conducted on MDD, these have seldom shed light on KP changes in late-life depression (LLD). We aimed to investigate whether tryptophan (TRP) metabolism and kynurenine (KYN) metabolism are imbalanced in LLD patients and to explore the differences in KP characteristics between early onset depression (EOD) and late onset depression (LOD) patients. We investigated 170 LLD patients (EOD 90, LOD 80) and 135 normal controls. Serum concentrations of TRP, KYN and kynurenic acid (KYNA) were detected by the liquid chromatography-tandem mass spectrometry method. Depressive symptoms were assessed by the 17-item Hamilton Depression Scale (HAMD-17). LLD patients exhibited lower levels of TRP, KYN, KYNA and KYNA/KYN ratio and a higher level of KYN/TRY ratio than normal controls. The decrease in TRP and the increase in KYN/TRP ratio were found in LOD patients. A low TRP level without increased KYN/TRP ratio was found in EOD patients. The "Depression" factor, which was extracted from HAMD-17 by the principal component factor analysis, was correlated with the TRP level and KYNA/KYN ratio in the EOD group, but no such correlation was found in the LOD group. KP changes were observed in LLD patients; LOD patients showed profound shifts in TRP metabolism, while EOD patients showed low TRP level and a shift in KYN metabolism. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Loss of Kynurenine 3-Mono-oxygenase Causes Proteinuria.

    Science.gov (United States)

    Korstanje, Ron; Deutsch, Konstantin; Bolanos-Palmieri, Patricia; Hanke, Nils; Schroder, Patricia; Staggs, Lynne; Bräsen, Jan H; Roberts, Ian S D; Sheehan, Susan; Savage, Holly; Haller, Hermann; Schiffer, Mario

    2016-11-01

    Changes in metabolite levels of the kynurenine pathway have been observed in patients with CKD, suggesting involvement of this pathway in disease pathogenesis. Our recent genetic analysis in the mouse identified the kynurenine 3-mono-oxygenase (KMO) gene (Kmo) as a candidate gene associated with albuminuria. This study investigated this association in more detail. We compared KMO abundance in the glomeruli of mice and humans under normal and diabetic conditions, observing a decrease in glomerular KMO expression with diabetes. Knockdown of kmo expression in zebrafish and genetic deletion of Kmo in mice each led to a proteinuria phenotype. We observed pronounced podocyte foot process effacement on long stretches of the filtration barrier in the zebrafish knockdown model and mild podocyte foot process effacement in the mouse model, whereas all other structures within the kidney remained unremarkable. These data establish the candidacy of KMO as a causal factor for changes in the kidney leading to proteinuria and indicate a functional role for KMO and metabolites of the tryptophan pathway in podocytes. Copyright © 2016 by the American Society of Nephrology.

  15. The activation of the kynurenine pathway in a rat model with renovascular hypertension.

    Science.gov (United States)

    Bartosiewicz, Jacek; Kaminski, Tomasz; Pawlak, Krystyna; Karbowska, Malgorzata; Tankiewicz-Kwedlo, Anna; Pawlak, Dariusz

    2017-04-01

    Hypertension is a serious condition that can lead to many health problems. The mechanisms underlying this process are still not fully understood. The kynurenine pathway may be involved in the occurrence and progression of hypertension. The purpose of this study was to examine the activity of peripheral kynurenine pathway in rats with renovascular hypertension in Goldblatt 2K1C model. Hypertension was induced in the experimental groups by constricting the renal artery of the left kidney of the rats. Determination of tryptophan (Trp) and kynurenine pathway metabolites was assessed by high-performance liquid chromatography in plasma and tissues obtained at 4, 8, and 16 weeks after the surgical intervention or sham surgery. Levels of Ang II were evaluated using commercial immuno-enzymatic ELISA kits. Surgical treatment led to increased values of mean blood pressure and systolic blood pressure, whereas Trp concentrations were decreased in experimental animals compared to appropriate controls. Simultaneously, the considerable increment of kynurenine pathway components and a significant increase in the activity of tryptophan 2,3-dioxygenase were observed in rats with developed hypertension in comparison with controls. There were no differences between Ang II levels in controls and experimental groups. The inverse relationship was between plasma Trp and both SBP and Ang II values, and Trp independently affected Ang II concentrations in hypertensive rats. In contrast, tryptophan 2,3-dioxygenase activity and plasma kynurenine metabolites positively correlated with blood pressure values as well as with Ang II levels in these animals. Moreover, kynurenine was independently connected with MBP. Renovascular hypertension influences kynurenine pathway and leads to an imbalance in Trp and its metabolite levels. Tryptophan 2,3-dioxygenase and part of the kynurenine metabolites in plasma and tissues positively correlated with blood pressure values and Ang II levels. Although the

  16. The Kynurenine Pathway: a Proposed Mechanism Linking Diabetes and Periodontal Disease in Diabetic Patients

    Directory of Open Access Journals (Sweden)

    Rishabh Kapila

    2011-07-01

    Full Text Available Introduction: Diabetes mellitus is a metabolic disease characte-rized by dysregulation of carbohydrate, protein and lipid metabolism. Diabetes could result, in part, in activation of tryptophan metabolism. Diabetic patients are more susceptible to gingivitis and periodontitis than healthy subjects. The salivary kynurenine derivatives are also implicated in the onset and development of periodontal dis-ease in humans.The hypothesis: We propose that the tryptophan metabolites via kynurenine pathway may lead to diabetes and an increased severity of periodontal disease in diabetic patients, thus linking both diabetes and periodontal disease.Evaluation of the hypothesis: Tryptophan has been found in significant amount in saliva in diabetic individuals in some studies, particularly tryptophan metabolites like kynurenine and anthranilic acid. Moreover, altered tryptophan metabolism has also been reported in the onset of periodontal disease. Thus, this correlation between diabetes mellitus, periodontal disease and salivary tryptophan metabolite levels could be related to the impaired kynurenine pathway metabolism of tryptophan.

  17. Perfil da aspartato aminotransferase e alanina aminotransferase e biometria do fígado de codornas japonesas

    OpenAIRE

    Barbosa,Anderson de Almeida; Müller,Elisa Sialino; Moraes,George Henrique Kling de; Umigi,Regina Tie; Barreto,Sergio Luiz de Toledo; Ferreira,Ronaldo Martins

    2010-01-01

    Objetivou-se determinar o perfil da aspartato aminotransferase e alanina aminotransferase e a biometria do fígado de codornas poedeiras (Coturnix coturnix japonica) de 1 a 25 dias de idade. Avaliaram-se o peso vivo e o peso do fígado e as atividades das aspartato e alanina aminotransferases no fígado utilizando-se 90 codornas de 1 dia de idade. O delineamento experimental foi inteiramente casualizado com seis idades e cinco repetições, considerando cada animal uma unidade experimental. Aos 1,...

  18. Ornithine aminotransferase deficiency: Diagnostic difficulties in neonatal presentation

    NARCIS (Netherlands)

    Cleary, M. A.; Dorland, L.; de Koning, T. J.; Poll-The, B. T.; Duran, M.; Mandell, R.; Shih, V. E.; Berger, R.; Olpin, S. E.; Besley, G. T. N.

    2005-01-01

    We describe two unrelated cases of ornithine aminotransferase (OAT) deficiency with rare neonatal presentation of hyperammonaemia. The diagnosis in the neonatal presentation of OAT deficiency is hampered as hyperornithinaemia is absent. Enzyme and mutation studies confirmed the diagnosis. OAT

  19. Aminotransferase and glutamate dehydrogenase activities in lactobacilli and streptococci

    Directory of Open Access Journals (Sweden)

    Guillermo Hugo Peralta

    Full Text Available ABSTRACT Aminotransferases and glutamate dehydrogenase are two main types of enzymes involved in the initial steps of amino acid catabolism, which plays a key role in the cheese flavor development. In the present work, glutamate dehydrogenase and aminotransferase activities were screened in twenty one strains of lactic acid bacteria of dairy interest, either cheese-isolated or commercial starters, including fifteen mesophilic lactobacilli, four thermophilic lactobacilli, and two streptococci. The strains of Streptococcus thermophilus showed the highest glutamate dehydrogenase activity, which was significantly elevated compared with the lactobacilli. Aspartate aminotransferase prevailed in most strains tested, while the levels and specificity of other aminotransferases were highly strain- and species-dependent. The knowledge of enzymatic profiles of these starter and cheese-isolated cultures is helpful in proposing appropriate combinations of strains for improved or increased cheese flavor.

  20. The Kynurenine Pathway: a Proposed Mechanism Linking Diabetes and Periodontal Disease in Diabetic Patients

    OpenAIRE

    Rishabh Kapila; KS Nagesh; Asha R. Iyengar; Subash BV. Adiga

    2011-01-01

    Introduction: Diabetes mellitus is a metabolic disease characte-rized by dysregulation of carbohydrate, protein and lipid metabolism. Diabetes could result, in part, in activation of tryptophan metabolism. Diabetic patients are more susceptible to gingivitis and periodontitis than healthy subjects. The salivary kynurenine derivatives are also implicated in the onset and development of periodontal dis-ease in humans.The hypothesis: We propose that the tryptophan metabolites via kynurenine path...

  1. Stimulatory effect of repeated treatment with lipopolysaccharide on a key enzyme of the kynurenine pathway in both genders in rats

    Directory of Open Access Journals (Sweden)

    Csanova A.

    2016-09-01

    Full Text Available The neuroprotective or neurotoxic effects of the products of the kynurenine pathway of tryptophan metabolism highly depend on the action of kynurenine-3-monooxygenase (KMO. The present results show increased concentrations of the KMO in the plasma of rats repeatedly exposed to an immune challenge. Increased concentrations of this key enzyme are likely to cause a shift of kynurenine pathway towards enhanced production of neurotoxic metabolites.

  2. Development of a series of aryl pyrimidine kynurenine monooxygenase inhibitors as potential therapeutic agents for the treatment of Huntington's disease.

    Science.gov (United States)

    Toledo-Sherman, Leticia M; Prime, Michael E; Mrzljak, Ladislav; Beconi, Maria G; Beresford, Alan; Brookfield, Frederick A; Brown, Christopher J; Cardaun, Isabell; Courtney, Stephen M; Dijkman, Ulrike; Hamelin-Flegg, Estelle; Johnson, Peter D; Kempf, Valerie; Lyons, Kathy; Matthews, Kimberly; Mitchell, William L; O'Connell, Catherine; Pena, Paula; Powell, Kendall; Rassoulpour, Arash; Reed, Laura; Reindl, Wolfgang; Selvaratnam, Suganathan; Friley, Weslyn Ward; Weddell, Derek A; Went, Naomi E; Wheelan, Patricia; Winkler, Christin; Winkler, Dirk; Wityak, John; Yarnold, Christopher J; Yates, Dawn; Munoz-Sanjuan, Ignacio; Dominguez, Celia

    2015-02-12

    We report on the development of a series of pyrimidine carboxylic acids that are potent and selective inhibitors of kynurenine monooxygenase and competitive for kynurenine. We describe the SAR for this novel series and report on their inhibition of KMO activity in biochemical and cellular assays and their selectivity against other kynurenine pathway enzymes. We describe the optimization process that led to the identification of a program lead compound with a suitable ADME/PK profile for therapeutic development. We demonstrate that systemic inhibition of KMO in vivo with this lead compound provides pharmacodynamic evidence for modulation of kynurenine pathway metabolites both in the periphery and in the central nervous system.

  3. Expression of the Kynurenine Pathway in Human Peripheral Blood Mononuclear Cells: Implications for Inflammatory and Neurodegenerative Disease.

    Science.gov (United States)

    Jones, Simon P; Franco, Nunzio F; Varney, Bianca; Sundaram, Gayathri; Brown, David A; de Bie, Josien; Lim, Chai K; Guillemin, Gilles J; Brew, Bruce J

    2015-01-01

    The kynurenine pathway is a fundamental mechanism of immunosuppression and peripheral tolerance. It is increasingly recognized as playing a major role in the pathogenesis of a wide variety of inflammatory, neurodegenerative and malignant disorders. However, the temporal dynamics of kynurenine pathway activation and metabolite production in human immune cells is currently unknown. Here we report the novel use of flow cytometry, combined with ultra high-performance liquid chromatography and gas chromatography-mass spectrometry, to sensitively quantify the intracellular expression of three key kynurenine pathway enzymes and the main kynurenine pathway metabolites in a time-course study. This is the first study to show that up-regulation of indoleamine 2,3-dioxygenase (IDO-1), kynurenine 3-monoxygenase (KMO) and quinolinate phosphoribosyltransferase (QPRT) is lacking in lymphocytes treated with interferon gamma. In contrast, peripheral monocytes showed a significant elevation of kynurenine pathway enzymes and metabolites when treated with interferon gamma. Expression of IDO-1, KMO and QPRT correlated significantly with activation of the kynurenine pathway (kynurenine:tryptophan ratio), quinolinic acid concentration and production of the monocyte derived, pro-inflammatory immune response marker: neopterin. Our results also describe an original and sensitive methodological approach to quantify kynurenine pathway enzyme expression in cells. This has revealed further insights into the potential role of these enzymes in disease processes.

  4. A single-run liquid chromatography mass spectrometry method to quantify neuroactive kynurenine pathway metabolites in rat plasma.

    Science.gov (United States)

    Orsatti, Laura; Speziale, Roberto; Orsale, Maria Vittoria; Caretti, Fulvia; Veneziano, Maria; Zini, Matteo; Monteagudo, Edith; Lyons, Kathryn; Beconi, Maria; Chan, Kelvin; Herbst, Todd; Toledo-Sherman, Leticia; Munoz-Sanjuan, Ignacio; Bonelli, Fabio; Dominguez, Celia

    2015-03-25

    Neuroactive metabolites in the kynurenine pathway of tryptophan catabolism are associated with neurodegenerative disorders. Tryptophan is transported across the blood-brain barrier and converted via the kynurenine pathway to N-formyl-L-kynurenine, which is further degraded to L-kynurenine. This metabolite can then generate a group of metabolites called kynurenines, most of which have neuroactive properties. The association of tryptophan catabolic pathway alterations with various central nervous system (CNS) pathologies has raised interest in analytical methods to accurately quantify kynurenines in body fluids. We here describe a rapid and sensitive reverse-phase HPLC-MS/MS method to quantify L-kynurenine (KYN), kynurenic acid (KYNA), 3-hydroxy-L-kynurenine (3HK) and anthranilic acid (AA) in rat plasma. Our goal was to quantify these metabolites in a single run; given their different physico-chemical properties, major efforts were devoted to develop a chromatography suitable for all metabolites that involves plasma protein precipitation with acetonitrile followed by chromatographic separation by C18 RP chromatography, detected by electrospray mass spectrometry. Quantitation range was 0.098-100 ng/ml for 3HK, 9.8-20,000 ng/ml for KYN, 0.49-1000 ng/ml for KYNA and AA. The method was linear (r>0.9963) and validation parameters were within acceptance range (calibration standards and QC accuracy within ±30%). Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Clinical Relevance of Kynurenine Pathway in HIV/AIDS : An Immune Checkpoint at the Crossroads of Metabolism and Inflammation

    NARCIS (Netherlands)

    Routy, Jean-Pierre; Mehraj, Vikram; Vyboh, Kishanda; Cao, Wei; Kema, Ido; Jenabian, Mohammad-Ali

    2015-01-01

    Tryptophan degradation along the kynurenine pathway is associated with a wide variety of pathophysiological processes, of which tumor tolerance and immune dysfunction in several chronic viral infections including HIV are well known. The kynurenine pathway is at the crossroads of metabolism and

  6. Interleukin-1β: A New Regulator of the Kynurenine Pathway Affecting Human Hippocampal Neurogenesis

    Science.gov (United States)

    Zunszain, Patricia A; Anacker, Christoph; Cattaneo, Annamaria; Choudhury, Shanas; Musaelyan, Ksenia; Myint, Aye Mu; Thuret, Sandrine; Price, Jack; Pariante, Carmine M

    2012-01-01

    Increased inflammation and reduced neurogenesis have been associated with the pathophysiology of major depression. Here, we show for the first time how IL-1β, a pro-inflammatory cytokine shown to be increased in depressed patients, decreases neurogenesis in human hippocampal progenitor cells. IL-1β was detrimental to neurogenesis, as shown by a decrease in the number of doublecortin-positive neuroblasts (−28%), and mature, microtubule-associated protein-2-positive neurons (−36%). Analysis of the enzymes that regulate the kynurenine pathway showed that IL-1β induced an upregulation of transcripts for indolamine-2,3-dioxygenase (IDO), kynurenine 3-monooxygenase (KMO), and kynureninase (42-, 12- and 30-fold increase, respectively, under differentiating conditions), the enzymes involved in the neurotoxic arm of the kynurenine pathway. Moreover, treatment with IL-1β resulted in an increase in kynurenine, the catabolic product of IDO-induced tryptophan metabolism. Interestingly, co-treatment with the KMO inhibitor Ro 61-8048 reversed the detrimental effects of IL-1β on neurogenesis. These observations indicate that IL-1β has a critical role in regulating neurogenesis whereas affecting the availability of tryptophan and the production of enzymes conducive to toxic metabolites. Our results suggest that inhibition of the kynurenine pathway may provide a new therapy to revert inflammatory-induced reduction in neurogenesis. PMID:22071871

  7. Vasorelaxing Action of the Kynurenine Metabolite, Xanthurenic Acid: The Missing Link in Endotoxin-Induced Hypotension?

    Directory of Open Access Journals (Sweden)

    Carmine Vecchione

    2017-05-01

    Full Text Available The kynurenine pathway of tryptophan metabolism is activated by pro-inflammatory cytokines. L-kynurenine, an upstream metabolite of the pathway, acts as a putative endothelium-derived relaxing factor, and has been hypothesized to play a causative role in the pathophysiology of inflammation-induced hypotension. Here, we show that xanthurenic acid (XA, the transamination product of 3-hydroxykynurenine, is more efficacious than L-kynurenine in causing relaxation of a resistance artery, but fails to relax pre-contracted aortic rings. In the mesenteric artery, XA enhanced activating phosphorylation of endothelial nitric oxide synthase (NOS, and the relaxing action of XA was abrogated by pharmacological inhibition of NOS and endothelial-derived hyperpolarizing factor. Systemic injection of XA reduced blood pressure in mice, and serum levels of XA increased by several fold in response to a pulse with the endotoxin, lipopolysaccharide (LPS. LPS-induced hypotension in mice was prevented by pre-treatment with the kynurenine monooxygenase (KMO inhibitor, Ro-618048, which lowered serum levels of XA but enhanced serum levels of L-kynurenine. UPF 648, another KMO inhibitor, could also abrogate LPS-induced hypotension. Our data identify XA as a novel vasoactive compound and suggest that formation of XA is a key event in the pathophysiology of inflammation-induced hypotension.

  8. Statin-related aminotransferase elevation according to baseline aminotransferases level in real practice in Korea.

    Science.gov (United States)

    Kim, H-S; Lee, S H; Kim, H; Lee, S-H; Cho, J H; Lee, H; Yim, H W; Kim, S-H; Choi, I-Y; Yoon, K-H; Kim, J H

    2016-06-01

    Higher rate of statin-related hepatotoxicity has been reported for Koreans than for Westerners. Moreover, statin-related aminotransferase elevation for those who show borderline levels of aspartate transaminase (AST) and alanine transaminase (ALT) (≤×3 of UNL) at baseline has not been fully investigated. Post-statin changes AST/ALT levels during the first year for 21 233 Korean outpatients at two large academic teaching hospitals from January 2009 to December 2013 were analysed using electronic health record data. The date of the first statin prescription was set as baseline. We also performed a comparative analysis of statin-related AST/ALT elevations according to the type of statin, followed by an analysis of clinical risk factors. The progression rate to abnormal AST/ALT values [>×3 the upper normal limit (UNL)] was significantly higher (2·4-16% vs. 0·3-1·7%, P ×1, but ≤×3 of UNL) compared with normal AST/ALT values at baseline. Those with normal baseline AST/ALT did not show significantly different progression rate between different statin medications (P = 0·801). However, patients taking pitavastatin (HR = 0·76, P = 0·657) were least likely to develop abnormal AST/ALT, whereas those taking fluvastatin (HR = 2·96, P = 0·029) were the most likely to develop abnormal AST/ALT compared with atorvastatin for patients who were with baseline borderline AST/ALT. However, given the small sample sizes and the observational nature of our study, these need further study. It is advisable to regularly monitor AST/ALT levels even in patients with AST/ALT increases >×1. Future studies should aim to determine the possible risk factors for each specific statin type by analysing various confounding variables. © 2016 The Authors. Journal of Clinical Pharmacy and Therapeutics Published by John Wiley & Sons Ltd.

  9. Changes in kynurenine pathway metabolism in Parkinson patients with L-DOPA-induced dyskinesia

    DEFF Research Database (Denmark)

    Havelund, Jesper F; Dammann Andersen, Andreas; Binzer, Michael

    2017-01-01

    L-DOPA is the most effective drug in the symptomatic treatment of Parkinson's disease, but chronic use is associated with L-DOPA-induced dyskinesia in more than half the patients after 10 years of treatment. L-DOPA treatment may affect tryptophan metabolism via the kynurenine pathway. Altered...... levels of kynurenine metabolites can affect glutamatergic transmission and may play a role in the development of L-DOPA-induced dyskinesia. In this study we assessed kynurenine metabolites in plasma and cerebrospinal fluid of Parkinson's disease patients and controls. Parkinson patients (n=26) were...... clinically assessed for severity of motor symptoms (UPDRS) and L-DOPA-induced dyskinesia (UDysRS). Plasma and cerebrospinal fluid samples were collected after overnight fasting and 1-2 hours after intake of L-DOPA or other anti-Parkinson medication. Metabolites were analyzed in plasma and cerebrospinal fluid...

  10. Kynurenine 3-monooxygenase polymorphisms: relevance for kynurenic acid synthesis in patients with schizophrenia and healthy controls.

    Science.gov (United States)

    Holtze, Maria; Saetre, Peter; Engberg, Göran; Schwieler, Lilly; Werge, Thomas; Andreassen, Ole A; Hall, Håkan; Terenius, Lars; Agartz, Ingrid; Jönsson, Erik G; Schalling, Martin; Erhardt, Sophie

    2012-01-01

    Patients with schizophrenia show increased brain and cerebrospinal fluid (CSF) concentrations of the endogenous N-methyl-D-aspartate receptor antagonist kynurenic acid (KYNA). This compound is an end-metabolite of the kynurenine pathway, and its formation indirectly depends on the activity of kynurenine 3-monooxygenase (KMO), the enzyme converting kynurenine to 3-hydroxykynurenine. We analyzed the association between KMO gene polymorphisms and CSF concentrations of KYNA in patients with schizophrenia and healthy controls. Fifteen single nucleotide polymorphisms (SNPs) were selected covering KMO and were analyzed in UNPHASED. We included 17 patients with schizophrenia and 33 controls in our study. We found an association between a KMO SNP (rs1053230), encoding an amino acid change of potential importance for substrate interaction, and CSF concentrations of KYNA. Given the limited sample size, the results are tentative until replication. Our results suggest that the nonsynonymous KMO SNP rs1053230 influences CSF concentrations of KYNA.

  11. Neurotoxic kynurenine metabolism is increased in the dorsal hippocampus and drives distinct depressive behaviors during inflammation.

    Science.gov (United States)

    Parrott, J M; Redus, L; Santana-Coelho, D; Morales, J; Gao, X; O'Connor, J C

    2016-10-18

    The kynurenine pathway of tryptophan metabolism has an important role in mediating the behavioral effects of inflammation, which has implications in understanding neuropsychiatric comorbidity and for the development of novel therapies. Inhibition of the rate-limiting enzyme, indoleamine 2,3-dioxygenase (IDO), prevents the development of many of these inflammation-induced preclinical behaviors. However, dysregulation in the balance of downstream metabolism, where neuroactive kynurenines are generated, is hypothesized to be a functionally important pathogenic feature of inflammation-induced depression. Here we utilized two novel transgenic mouse strains to directly test the hypothesis that neurotoxic kynurenine metabolism causes depressive-like behavior following peripheral immune activation. Wild-type (WT) or kynurenine 3-monooxygenase (KMO)-deficient (KMO -/- ) mice were administered either lipopolysaccharide (LPS, 0.5 mg kg -1 ) or saline intraperitoneally. Depressive-like behavior was measured across multiple domains 24 h after immune challenge. LPS precipitated a robust depressive-like phenotype, but KMO -/- mice were specifically protected from LPS-induced immobility in the tail suspension test (TST) and reduced spontaneous alternations in the Y-maze. Direct administration of 3-hydroxykynurenine, the metabolic product of KMO, caused a dose-dependent increase in depressive-like behaviors. Mice with targeted deletion of 3-hydroxyanthranilic acid dioxygenase (HAAO), the enzyme that generates quinolinic acid, were similarly challenged with LPS. Similar to KMO -/- mice, LPS failed to increase immobility during the TST. Whereas kynurenine metabolism was generally increased in behaviorally salient brain regions, a distinct shift toward KMO-dependent kynurenine metabolism occurred in the dorsal hippocampus in response to LPS. Together, these results demonstrate that KMO is a pivotal mediator of hippocampal-dependent depressive-like behaviors induced by peripheral

  12. Elevated Levels of Peripheral Kynurenine Decrease Bone Strength in Rats with Chronic Kidney Disease

    Directory of Open Access Journals (Sweden)

    Bartlomiej Kalaska

    2017-10-01

    Full Text Available The diagnosis and treatment of bone disorders in patients with chronic kidney disease (CKD represent a clinical challenge. CKD leads to mineral and bone complications starting early in the course of renal failure. Recently, we have observed the positive relationship between intensified central kynurenine turnover and bone strength in rats with subtotal 5/6 nephrectomy (5/6 Nx-induced CKD. The aim of the present study was to determine the association between peripheral kynurenine pathway metabolites and bone strength in rats with 5/6 Nx-induced CKD. The animals were sacrificed 1 and 3 months after 5/6 Nx or sham operation. Nephrectomized rats presented higher concentrations of serum creatinine, urea nitrogen, and parathyroid hormone both 1 and 3 months after nephrectomy. These animals revealed higher concentrations of kynurenine and 3-hydroxykynurenine in the serum and higher gene expression of aryl hydrocarbon receptor (AhR as a physiological receptor for kynurenine and AhR-dependent cytochrome in the bone tissue. Furthermore, nephrectomy significantly increased the number of osteoclasts in the bone without affecting their resorptive activity measured in serum. These changes were particularly evident in rats 1 month after 5/6 Nx. The main bone biomechanical parameters of the tibia were unchanged between nephrectomized and sham-operated rats but were significantly increased in older compared to younger animals. A similar trend was observed for geometrical parameters measured with calipers, bone mineral density based on Archimedes' method and image of bone microarchitecture obtained from micro-computed tomography analyses of tibial cortical bone. In nephrectomized animals, peripheral kynurenine levels correlated negatively with the main parameters of bone biomechanics, bone geometry, and bone mineral density values. In conclusion, our data suggest that CKD-induced elevated levels of peripheral kynurenine cause pathological changes in bone

  13. Metabolism of /sup 14/C-labelled L-tryptophan, L-kynurenine, and hydroxy-L-kynurenine in miners with scleroderma

    Energy Technology Data Exchange (ETDEWEB)

    Hankes, L.V.; De Bruin, E.; Jansen, C.R.; Vorster, L.; Schmaeler, M.

    1977-03-19

    Six South African white miners were studied with the 2-g L-tryptophan load test and tracer doses of L-tryptophan-7a-/sup 14/C, L-kynurenine-keto-/sup 14/C and hydroxy-L-kynurenine-keto-/sup 14/C. The breath /sup 14/CO/sub 2/ and 14 urinary metabolites were measured. When they were compared with a previous study of American women with scleroderma, similar /sup 14/CO/sub 2/ and tryptophan metabolite excretion patterns were observed in the data from the miners. The labelled quinolinic acid excretion was more significantly elevated in the South African miners' urine than in the urine of the American women. The data from both studies suggest that some patients with scleroderma have an altered step in the tryptophan metabolic pathway after hydroxy-anthranilic acid. What relationship exists between the induction of pulmonary silicosis and the subsequent development of scleroderma, requires additional human studies.

  14. UVA Light-excited Kynurenines Oxidize Ascorbate and Modify Lens Proteins through the Formation of Advanced Glycation End Products

    Science.gov (United States)

    Linetsky, Mikhail; Raghavan, Cibin T.; Johar, Kaid; Fan, Xingjun; Monnier, Vincent M.; Vasavada, Abhay R.; Nagaraj, Ram H.

    2014-01-01

    Advanced glycation end products (AGEs) contribute to lens protein pigmentation and cross-linking during aging and cataract formation. In vitro experiments have shown that ascorbate (ASC) oxidation products can form AGEs in proteins. However, the mechanisms of ASC oxidation and AGE formation in the human lens are poorly understood. Kynurenines are tryptophan oxidation products produced from the indoleamine 2,3-dioxygenase (IDO)-mediated kynurenine pathway and are present in the human lens. This study investigated the ability of UVA light-excited kynurenines to photooxidize ASC and to form AGEs in lens proteins. UVA light-excited kynurenines in both free and protein-bound forms rapidly oxidized ASC, and such oxidation occurred even in the absence of oxygen. High levels of GSH inhibited but did not completely block ASC oxidation. Upon UVA irradiation, pigmented proteins from human cataractous lenses also oxidized ASC. When exposed to UVA light (320–400 nm, 100 milliwatts/cm2, 45 min to 2 h), young human lenses (20–36 years), which contain high levels of free kynurenines, lost a significant portion of their ASC content and accumulated AGEs. A similar formation of AGEs was observed in UVA-irradiated lenses from human IDO/human sodium-dependent vitamin C transporter-2 mice, which contain high levels of kynurenines and ASC. Our data suggest that kynurenine-mediated ASC oxidation followed by AGE formation may be an important mechanism for lens aging and the development of senile cataracts in humans. PMID:24798334

  15. Acute Kynurenine Challenge Disrupts Sleep-Wake Architecture and Impairs Contextual Memory in Adult Rats.

    Science.gov (United States)

    Pocivavsek, Ana; Baratta, Annalisa M; Mong, Jessica A; Viechweg, Shaun S

    2017-11-01

    Tryptophan metabolism via the kynurenine pathway may represent a key molecular link between sleep loss and cognitive dysfunction. Modest increases in the kynurenine pathway metabolite kynurenic acid (KYNA), which acts as an antagonist at N-methyl-d-aspartate and α7 nicotinic acetylcholine receptors in the brain, result in cognitive impairments. As glutamatergic and cholinergic neurotransmissions are critically involved in modulation of sleep, our current experiments tested the hypothesis that elevated KYNA adversely impacts sleep quality. Adult male Wistar rats were treated with vehicle (saline) and kynurenine (25, 50, 100, and 250 mg/kg), the direct bioprecursor of KYNA, intraperitoneally at zeitgeber time (ZT) 0 to rapidly increase brain KYNA. Levels of KYNA in the brainstem, cortex, and hippocampus were determined at ZT 0, ZT 2, and ZT 4, respectively. Analyses of vigilance state-related parameters categorized as wake, rapid eye movement (REM), and non-REM (NREM) as well as spectra power analysis during NREM and REM were assessed during the light phase. Separate animals were tested in the passive avoidance paradigm, testing contextual memory. When KYNA levels were elevated in the brain, total REM duration was reduced and total wake duration was increased. REM and wake architecture, assessed as number of vigilance state bouts and average duration of each bout, and theta power during REM were significantly impacted. Kynurenine challenge impaired performance in the hippocampal-dependent contextual memory task. Our results introduce kynurenine pathway metabolism and formation of KYNA as a novel molecular target contributing to sleep disruptions and cognitive impairments. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

  16. Influence of kynurenine 3-monooxygenase (KMO) gene polymorphism on cognitive function in schizophrenia✰,✰✰

    Science.gov (United States)

    Wonodi, Ikwunga; McMahon, Robert P.; Krishna, Nithin; Mitchell, Braxton D.; Liu, Judy; Glassman, Matthew; Hong, L. Elliot; Gold, James M.

    2015-01-01

    Background Cognitive deficits compromise quality of life and productivity for individuals with schizophrenia and have no effective treatments. Preclinical data point to the kynurenine pathway of tryptophan metabolism as a potential target for pro-cognitive drug development. We have previously demonstrated association of a kynurenine 3-monooxygenase (KMO) gene variant with reduced KMO gene expression in postmortem schizophrenia cortex, and neurocognitive endophenotypic deficits in a clinical sample. KMO encodes kynurenine 3-monooxygenase (KMO), the rate-limiting microglial enzyme of cortical kynurenine metabolism. Aberration of the KMO gene might be the proximal cause of impaired cortical kynurenine metabolism observed in schizophrenia. However, the relationship between KMO variation and cognitive function in schizophrenia is unknown. This study examined the effects of the KMO rs2275163C>T C (risk) allele on cognitive function in schizophrenia. Methods We examined the association of KMO polymorphisms with general neuropsychological performance and P50 gating in a sample of 150 schizophrenia and 95 healthy controls. Results Consistent with our original report, the KMO rs2275163C>T C (risk) allele was associated with deficits in general neuropsychological performance, and this effect was more marked in schizophrenia compared with controls. Additionally, the C (Arg452) allele of the missense rs1053230C>T variant (KMO Arg452Cys) showed a trend effect on cognitive function. Neither variant affected P50 gating. Conclusions These data suggest that KMO variation influences a range of cognitive domains known to predict functional outcome. Extensive molecular characterization of this gene would elucidate its role in cognitive function with implications for vertical integration with basic discovery. PMID:25464917

  17. Adaptive and Behavioral Changes in Kynurenine 3-Monooxygenase Knockout Mice: Relevance to Psychotic Disorders.

    Science.gov (United States)

    Erhardt, Sophie; Pocivavsek, Ana; Repici, Mariaelena; Liu, Xi-Cong; Imbeault, Sophie; Maddison, Daniel C; Thomas, Marian A R; Smalley, Joshua L; Larsson, Markus K; Muchowski, Paul J; Giorgini, Flaviano; Schwarcz, Robert

    2017-11-15

    Kynurenine 3-monooxygenase converts kynurenine to 3-hydroxykynurenine, and its inhibition shunts the kynurenine pathway-which is implicated as dysfunctional in various psychiatric disorders-toward enhanced synthesis of kynurenic acid, an antagonist of both α7 nicotinic acetylcholine and N-methyl-D-aspartate receptors. Possibly as a result of reduced kynurenine 3-monooxygenase activity, elevated central nervous system levels of kynurenic acid have been found in patients with psychotic disorders, including schizophrenia. In the present study, we investigated adaptive-and possibly regulatory-changes in mice with a targeted deletion of Kmo (Kmo -/- ) and characterized the kynurenine 3-monooxygenase-deficient mice using six behavioral assays relevant for the study of schizophrenia. Genome-wide differential gene expression analyses in the cerebral cortex and cerebellum of these mice identified a network of schizophrenia- and psychosis-related genes, with more pronounced alterations in cerebellar tissue. Kynurenic acid levels were also increased in these brain regions in Kmo -/- mice, with significantly higher levels in the cerebellum than in the cerebrum. Kmo -/- mice exhibited impairments in contextual memory and spent less time than did controls interacting with an unfamiliar mouse in a social interaction paradigm. The mutant animals displayed increased anxiety-like behavior in the elevated plus maze and in a light/dark box. After a D-amphetamine challenge (5 mg/kg, intraperitoneal), Kmo -/- mice showed potentiated horizontal activity in the open field paradigm. Taken together, these results demonstrate that the elimination of Kmo in mice is associated with multiple gene and functional alterations that appear to duplicate aspects of the psychopathology of several neuropsychiatric disorders. Copyright © 2016. Published by Elsevier Inc.

  18. Kynurenine 3-monooxygenase is implicated in antidepressants-responsive depressive-like behaviors and monoaminergic dysfunctions.

    Science.gov (United States)

    Tashiro, Tomoyuki; Murakami, Yuki; Mouri, Akihiro; Imamura, Yukio; Nabeshima, Toshitaka; Yamamoto, Yasuko; Saito, Kuniaki

    2017-01-15

    l-Tryptophan (TRP) is metabolized via serotonin and kynurenine pathways (KP). Several studies have demonstrated that abnormality of both pathways is involved in the pathogenesis of major depressive disorder (MDD). Kynurenine 3-monooxygenase (KMO), a pivotal enzyme in the KP, has been suggested to play major roles in physiological and pathological events mediated by bioactive kynurenine metabolites. In this study, we investigated the role of KMO in the emotional and cognitive functions by using KMO knockout (KO) mice. We measured contents of TRP and monoamines and their metabolites in the serum and hippocampus of KMO KO mice. Further, we investigated whether antidepressants improved the depressive-like behaviors in KMO KO mice. KMO KO mice showed depressive-like behaviors such as decreased sucrose preference and increased immobility in the forced swimming test and high anxiety by decreased time spent in the center area of open field. But, there was no difference in spontaneous alternation in Y-maze test, counts of rearing or locomotor activity. Higher contents of TRP metabolites such as kynurenine (KYN), kynurenic acid (KA), anthranilic acid (AA), and 3-hydroxykynurenine (3-HK) in the serum and hippocampus and decreased serotonin turnover and higher content of normetanephrine (NM) in the hippocampus were observed in the KMO KO mice. Although both antidepressant attenuated increase of immobility, sertraline but not imipramine improved decrease of sucrose preference in the KMO KO mice. These findings suggested that KMO KO mice show antidepressants-responsive depressive-like behaviors and monoaminergic dysfunctions via abnormality of kynurenine metabolism with good validities as MDD model. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Influence of kynurenine 3-monooxygenase (KMO) gene polymorphism on cognitive function in schizophrenia.

    Science.gov (United States)

    Wonodi, Ikwunga; McMahon, Robert P; Krishna, Nithin; Mitchell, Braxton D; Liu, Judy; Glassman, Matthew; Hong, L Elliot; Gold, James M

    2014-12-01

    Cognitive deficits compromise quality of life and productivity for individuals with schizophrenia and have no effective treatments. Preclinical data point to the kynurenine pathway of tryptophan metabolism as a potential target for pro-cognitive drug development. We have previously demonstrated association of a kynurenine 3-monooxygenase (KMO) gene variant with reduced KMO gene expression in postmortem schizophrenia cortex, and neurocognitive endophenotypic deficits in a clinical sample. KMO encodes kynurenine 3-monooxygenase (KMO), the rate-limiting microglial enzyme of cortical kynurenine metabolism. Aberration of the KMO gene might be the proximal cause of impaired cortical kynurenine metabolism observed in schizophrenia. However, the relationship between KMO variation and cognitive function in schizophrenia is unknown. This study examined the effects of the KMO rs2275163C>T C (risk) allele on cognitive function in schizophrenia. We examined the association of KMO polymorphisms with general neuropsychological performance and P50 gating in a sample of 150 schizophrenia and 95 healthy controls. Consistent with our original report, the KMO rs2275163C>T C (risk) allele was associated with deficits in general neuropsychological performance, and this effect was more marked in schizophrenia compared with controls. Additionally, the C (Arg452) allele of the missense rs1053230C>T variant (KMO Arg452Cys) showed a trend effect on cognitive function. Neither variant affected P50 gating. These data suggest that KMO variation influences a range of cognitive domains known to predict functional outcome. Extensive molecular characterization of this gene would elucidate its role in cognitive function with implications for vertical integration with basic discovery. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Glial and tissue-specific regulation of Kynurenine Pathway dioxygenases by acute stress of mice

    Directory of Open Access Journals (Sweden)

    Carlos R. Dostal

    2017-12-01

    Full Text Available Stressors activate the hypothalamic-pituitary-adrenal (HPA axis and immune system eliciting changes in cognitive function, mood and anxiety. An important link between stress and altered behavior is stimulation of the Kynurenine Pathway which generates neuroactive and immunomodulatory kynurenines. Tryptophan entry into this pathway is controlled by rate-limiting indoleamine/tryptophan 2,3-dioxygenases (DOs: Ido1, Ido2, Tdo2. Although implicated as mediating changes in behavior, detecting stress-induced DO expression has proven inconsistent. Thus, C57BL/6J mice were used to characterize DO expression in brain-regions, astrocytes and microglia to characterize restraint-stress-induced DO expression. Stress increased kynurenine in brain and plasma, demonstrating increased DO activity. Of three Ido1 transcripts, only Ido1-v1 expression was increased by stress and within astrocytes, not microglia, indicating transcript- and glial-specificity. Stress increased Ido1-v1 only in frontal cortex and hypothalamus, indicating brain-region specificity. Of eight Ido2 transcripts, Ido2-v3 expression was increased by stress, again only within astrocytes. Likewise, stress increased Tdo2-FL expression in astrocytes, not microglia. Interestingly, Ido2 and Tdo2 transcripts were not correspondingly induced in Ido1-knockout (Ido1KO mice, suggesting that Ido1 is necessary for the central DO response to acute stress. Unlike acute inflammatory models resulting in DO induction within microglia, only astrocyte DO expression was increased by acute restraint-stress, defining their unique role during stress-dependent activation of the Kynurenine Pathway. Keywords: Stress, Ido, Tdo, Kynurenine, Astrocyte, Liver

  1. Kynurenine pathway metabolism following prenatal KMO inhibition and in Mecp2+/- mice, using liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Forrest, Caroline M; Kennedy, Peter G E; Rodgers, Jean; Dalton, R Neil; Turner, Charles; Darlington, L Gail; Cobb, Stuart R; Stone, Trevor W

    2016-11-01

    To quantify the full range of tryptophan metabolites along the kynurenine pathway, a liquid chromatography - tandem mass spectrometry method was developed and used to analyse brain extracts of rodents treated with the kynurenine-3-mono-oxygenase (KMO) inhibitor Ro61-8048 during pregnancy. There were significant increases in the levels of kynurenine, kynurenic acid, anthranilic acid and 3-hydroxy-kynurenine (3-HK) in the maternal brain after 5 h but not 24 h, while the embryos exhibited high levels of kynurenine, kynurenic acid and anthranilic acid after 5 h which were maintained at 24 h post-treatment. At 24 h there was also a strong trend to an increase in quinolinic acid levels (P = 0.055). No significant changes were observed in any of the other kynurenine metabolites. The results confirm the marked increase in the accumulation of some neuroactive kynurenines when KMO is inhibited, and re-emphasise the potential importance of changes in anthranilic acid. The prolonged duration of metabolite accumulation in the embryo brains indicates a trapping of compounds within the embryonic CNS independently of maternal levels. When brains were examined from young mice heterozygous for the meCP2 gene - a potential model for Rett syndrome - no differences were noted from control mice, suggesting that the proposed roles for kynurenines in autism spectrum disorder are not relevant to Rett syndrome, supporting its recognition as a distinct, independent, condition. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Indoleamine 2,3-dioxygenase-dependent neurotoxic kynurenine metabolism mediates inflammation-induced deficit in recognition memory

    Science.gov (United States)

    Heisler, Jillian M.; O’Connor, Jason C.

    2015-01-01

    Cognitive dysfunction in depression is a prevalent and debilitating symptom that is poorly treated by the currently available pharmacotherapies. Research over the past decade has provided evidence for proinflammatory involvement in the neurobiology of depressive disorders and symptoms associated with these disorders, including aspects of memory dysfunction. Recent clinical studies implicate inflammation-related changes in kynurenine metabolism as a potential pathogenic factor in the development of a range of depressive symptoms, including deficits in cognition and memory. Additionally, preclinical work has demonstrated a number of mood-related depressive-like behaviors to be dependent on indoleamine 2,3-dioxygenase-1 (IDO1), the inflammation-induced rate-limiting enzyme of the kynurenine pathway. Here, we demonstrate in a mouse model, that peripheral administration of endotoxin induced a deficit in recognition memory. Mice deficient in IDO were protected from cognitive impairment. Furthermore, endotoxin-induced inflammation increased kynurenine metabolism within the perirhinal/entorhinal cortices, brain regions which have been implicated in recognition memory. A single peripheral injection of kynurenine, the metabolic product of IDO1, was sufficient to induce a deficit in recognition memory in both control and IDO null mice. Finally, kynurenine monooxygenase (KMO) deficient mice were also protected from inflammation-induced deficits on novel object recognition. These data implicate IDO-dependent neurotoxic kynurenine metabolism as a pathogenic factor for cognitive dysfunction in inflammation-induced depressive disorders and a potential novel target for the treatment of these disorders. PMID:26130057

  3. Indoleamine 2,3-dioxygenase-dependent neurotoxic kynurenine metabolism mediates inflammation-induced deficit in recognition memory.

    Science.gov (United States)

    Heisler, Jillian M; O'Connor, Jason C

    2015-11-01

    Cognitive dysfunction in depression is a prevalent and debilitating symptom that is poorly treated by the currently available pharmacotherapies. Research over the past decade has provided evidence for proinflammatory involvement in the neurobiology of depressive disorders and symptoms associated with these disorders, including aspects of memory dysfunction. Recent clinical studies implicate inflammation-related changes in kynurenine metabolism as a potential pathogenic factor in the development of a range of depressive symptoms, including deficits in cognition and memory. Additionally, preclinical work has demonstrated a number of mood-related depressive-like behaviors to be dependent on indoleamine 2,3-dioxygenase-1 (IDO1), the inflammation-induced rate-limiting enzyme of the kynurenine pathway. Here, we demonstrate in a mouse model, that peripheral administration of endotoxin induced a deficit in recognition memory. Mice deficient in IDO were protected from cognitive impairment. Furthermore, endotoxin-induced inflammation increased kynurenine metabolism within the perirhinal/entorhinal cortices, brain regions which have been implicated in recognition memory. A single peripheral injection of kynurenine, the metabolic product of IDO1, was sufficient to induce a deficit in recognition memory in both control and IDO null mice. Finally, kynurenine monooxygenase (KMO) deficient mice were also protected from inflammation-induced deficits on novel object recognition. These data implicate IDO-dependent neurotoxic kynurenine metabolism as a pathogenic factor for cognitive dysfunction in inflammation-induced depressive disorders and a potential novel target for the treatment of these disorders. Published by Elsevier Inc.

  4. Biocatalytic potential of vanillin aminotransferase from Capsicum chinense

    Science.gov (United States)

    2014-01-01

    Background The conversion of vanillin to vanillylamine is a key step in the biosynthetic route towards capsaicinoids in pungent cultivars of Capsicum sp. The reaction has previously been annotated to be catalysed by PAMT (putative aminotransferase; [GenBank: AAC78480.1, Swiss-Prot: O82521]), however, the enzyme has previously not been biochemically characterised in vitro. Results The biochemical activity of the transaminase was confirmed by direct measurement of the reaction with purified recombinant enzyme. The enzyme accepted pyruvate, and oxaloacetate but not 2-oxoglutarate as co-substrate, which is in accordance with other characterised transaminases from the plant kingdom. The enzyme was also able to convert (S)-1-phenylethylamine into acetophenone with high stereo-selectivity. Additionally, it was shown to be active at a broad pH range. Conclusions We suggest PAMT to be renamed to VAMT (vanillin aminotransferase, abbreviation used in this study) as formation of vanillin from vanillylamine could be demonstrated. Furthermore, due to high stereoselectivity and activity at physiological pH, VAMT is a suitable candidate for biocatalytic transamination in a recombinant whole-cell system. PMID:24712445

  5. Salivary lactate dehydrogenase and aminotransferases in diabetic patients.

    Science.gov (United States)

    Malicka, Barbara; Skoskiewicz-Malinowska, Katarzyna; Kaczmarek, Urszula

    2016-11-01

    Diabetes mellitus (DM) is a group of metabolic diseases resulting from impaired insulin secretion and/or action. DM is characterized by hyperglycemia that can lead to the dysfunction or damage of organs, including the salivary glands.The aim of this study was to compare the levels of salivary lactate dehydrogenase (LDH), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) in diabetic patients.The study was approved by the Bioethics Committee of Wroclaw Medical University (Poland). The study comprised 90 adults of both sexes, aged 21 to 57 years. The patients were divided into 3 groups: type 1 diabetics (D1), type 2 diabetics (D2), and a healthy control group (C). Each group consisted of 30 age- and sex-matched subjects. Total protein (P, by Lowry method), LDH, AST, ALT (with Alpha Diagnostics kits), and salivary flow rate were measured in unstimulated mixed saliva. The level of glycosylated hemoglobin (HbA1c) was measured with DCA 2000 Reagent Kit. The obtained data were analyzed using the Mann-Whitney U test and the Spearman rank at a significance level of P salivary LDH, AST, and ALT in D1 compared with D2 and C confirm that salivary glands of D1 might be attributed to autoimmunological damage associated with the pathomechanism of DM.

  6. Role of aminotransferases in glutamate metabolism of human erythrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Ellinger, James J. [University of Wisconsin-Madison, Department of Biochemistry (United States); Lewis, Ian A. [Princeton University, Lewis-Sigler Institute for Integrative Genomics (United States); Markley, John L., E-mail: markley@nmrfam.wisc.edu [University of Wisconsin-Madison, Department of Biochemistry (United States)

    2011-04-15

    Human erythrocytes require a continual supply of glutamate to support glutathione synthesis, but are unable to transport this amino acid across their cell membrane. Consequently, erythrocytes rely on de novo glutamate biosynthesis from {alpha}-ketoglutarate and glutamine to maintain intracellular levels of glutamate. Erythrocytic glutamate biosynthesis is catalyzed by three enzymes, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and glutamine aminohydrolase (GA). Although the presence of these enzymes in RBCs has been well documented, the relative contributions of each pathway have not been established. Understanding the relative contributions of each biosynthetic pathway is critical for designing effective therapies for sickle cell disease, hemolytic anemia, pulmonary hypertension, and other glutathione-related disorders. In this study, we use multidimensional {sup 1}H-{sup 13}C nuclear magnetic resonance (NMR) spectroscopy and multiple reaction mode mass spectrometry (MRM-MS) to measure the kinetics of de novo glutamate biosynthesis via AST, ALT, and GA in intact cells and RBC lysates. We show that up to 89% of the erythrocyte glutamate pool can be derived from ALT and that ALT-derived glutamate is subsequently used for glutathione synthesis.

  7. Kynurenine 3-monooxygenase polymorphisms: relevance for kynurenic acid synthesis in patients with schizophrenia and healthy controls

    DEFF Research Database (Denmark)

    Holtze, Maria; Saetre, Peter; Engberg, Göran

    2012-01-01

    on the activity of kynurenine 3-monooxygenase (KMO), the enzyme converting kynurenine to 3-hydroxykynurenine. Methods: We analyzed the association between KMO gene polymorphisms and CSF concentrations of KYNA in patients with schizophrenia and healthy controls. Fifteen single nucleotide polymorphisms (SNPs) were...... selected covering KMO and were analyzed in UNPHASED. Results: We included 17 patients with schizophrenia and 33 controls in our study. We found an association between a KMO SNP (rs1053230), encoding an amino acid change of potential importance for substrate interaction, and CSF concentrations of KYNA....... Limitations: Given the limited sample size, the results are tentative until replication. Conclusion: Our results suggest that the nonsynonymous KMO SNP rs1053230 influences CSF concentrations of KYNA....

  8. The causative role and therapeutic potential of the kynurenine pathway in neurodegenerative disease.

    Science.gov (United States)

    Amaral, Marta; Outeiro, Tiago F; Scrutton, Nigel S; Giorgini, Flaviano

    2013-06-01

    Metabolites of the kynurenine pathway (KP), which arise from the degradation of tryptophan, have been studied in detail for over a century and garnered the interest of the neuroscience community in the late 1970s and early 1980s with work uncovering the neuromodulatory potential of this pathway. Much research in the following decades has found that perturbations in the levels of KP metabolites likely contribute to the pathogenesis of several neurodegenerative diseases. More recently, it has become apparent that targeting KP enzymes, in particular kynurenine 3-monooxygenase (KMO), may hold substantial therapeutic potential for these disorders. Here we provide an overview of the KP, the neuroactive properties of KP metabolites and their role in neurodegeneration. We also discuss KMO as a therapeutic target for these disorders, and our recent resolution of the crystallographic structure of KMO, which will permit the development of new and improved KMO inhibitors which may ultimately expedite clinical application of these compounds.

  9. The Genetic Link between Parkinson's Disease and the Kynurenine Pathway Is Still Missing.

    Science.gov (United States)

    Török, Nóra; Török, Rita; Szolnoki, Zoltán; Somogyvári, Ferenc; Klivényi, Péter; Vécsei, László

    2015-01-01

    Background. There is substantial evidence that the kynurenine pathway (KP) plays a role in the normal physiology of the brain and is involved in the pathology of neurodegenerative disorders such as Huntington's disease and Parkinson's disease (PD). Objective. We set out to investigate the potential roles in PD of single nucleotide polymorphisms (SNPs) from one of the key enzymes of the KP, kynurenine 3-monooxygenase (KMO). Methods. 105 unrelated, clinically definitive PD patients and 131 healthy controls were enrolled to investigate the possible effects of the different alleles of KMO. Fluorescently labeled TaqMan probes were used for allele discrimination. Results. None of the four investigated SNPs proved to be associated with PD or influenced the age at onset of the disease. Conclusions. The genetic link between the KP and PD is still missing. The investigated SNPs presumably do not appear to influence the function of KMO and probably do not contain binding sites for regulatory proteins of relevance in PD. This is the first study to assess the genetic background behind the biochemical alterations of the kynurenine pathway in PD, directing the attention to this previously unexamined field.

  10. Absence of kynurenine 3-monooxygenase reduces mortality of acute viral myocarditis in mice.

    Science.gov (United States)

    Kubo, Hisako; Hoshi, Masato; Mouri, Akihiro; Tashita, Chieko; Yamamoto, Yasuko; Nabeshima, Toshitaka; Saito, Kuniaki

    2017-01-01

    Infection of the encephalomyocarditis virus (EMCV) in mice is an established model for viral myocarditis. Previously, we have demonstrated that indoleamine 2,3-dioxygenase (IDO), an L-tryptophan - kynurenine pathway (KP) enzyme, affects acute viral myocarditis. However, the roles of KP metabolites in EMCV infection remain unclear. Kynurenine 3-monooxygenase (KMO) is one of the key regulatory enzymes, which metabolizes kynurenine to 3-hydroxykynurenine in the KP. Therefore, we examined the role of KMO in acute viral infection by comparing between KMO -/- mice and KMO +/+ mice. KMO deficiency resulted in suppressed mortality after EMCV infection. The number of infiltrating cells and F4/80 + cells in KMO -/- mice was suppressed compared with those in KMO +/+ mice. KMO -/- mice showed significantly increased levels of serum KP metabolites, and induction of KMO expression upon EMCV infection was involved in its effect on mortality through EMCV suppression. Furthermore, KMO -/- mice showed significantly suppression of CCL2, CCL3 and CCL4 on day 2 and CXCL1 on day 4 after infection. These results suggest that increased KP metabolites reduced chemokine production, resulting in suppressed mortality upon KMO knockdown in EMCV infection. KP metabolites may thus provide an effective strategy for treating acute viral myocarditis. Copyright © 2016 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  11. Kynurenine-3-monooxygenase inhibition prevents multiple organ failure in rodent models of acute pancreatitis.

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    Mole, Damian J; Webster, Scott P; Uings, Iain; Zheng, Xiaozhong; Binnie, Margaret; Wilson, Kris; Hutchinson, Jonathan P; Mirguet, Olivier; Walker, Ann; Beaufils, Benjamin; Ancellin, Nicolas; Trottet, Lionel; Bénéton, Véronique; Mowat, Christopher G; Wilkinson, Martin; Rowland, Paul; Haslam, Carl; McBride, Andrew; Homer, Natalie Z M; Baily, James E; Sharp, Matthew G F; Garden, O James; Hughes, Jeremy; Howie, Sarah E M; Holmes, Duncan S; Liddle, John; Iredale, John P

    2016-02-01

    Acute pancreatitis (AP) is a common and devastating inflammatory condition of the pancreas that is considered to be a paradigm of sterile inflammation leading to systemic multiple organ dysfunction syndrome (MODS) and death. Acute mortality from AP-MODS exceeds 20% (ref. 3), and the lifespans of those who survive the initial episode are typically shorter than those of the general population. There are no specific therapies available to protect individuals from AP-MODS. Here we show that kynurenine-3-monooxygenase (KMO), a key enzyme of tryptophan metabolism, is central to the pathogenesis of AP-MODS. We created a mouse strain that is deficient for Kmo (encoding KMO) and that has a robust biochemical phenotype that protects against extrapancreatic tissue injury to the lung, kidney and liver in experimental AP-MODS. A medicinal chemistry strategy based on modifications of the kynurenine substrate led to the discovery of the oxazolidinone GSK180 as a potent and specific inhibitor of KMO. The binding mode of the inhibitor in the active site was confirmed by X-ray co-crystallography at 3.2 Å resolution. Treatment with GSK180 resulted in rapid changes in the levels of kynurenine pathway metabolites in vivo, and it afforded therapeutic protection against MODS in a rat model of AP. Our findings establish KMO inhibition as a novel therapeutic strategy in the treatment of AP-MODS, and they open up a new area for drug discovery in critical illness.

  12. The Genetic Link between Parkinson’s Disease and the Kynurenine Pathway Is Still Missing

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    Nóra Török

    2015-01-01

    Full Text Available Background. There is substantial evidence that the kynurenine pathway (KP plays a role in the normal physiology of the brain and is involved in the pathology of neurodegenerative disorders such as Huntington’s disease and Parkinson’s disease (PD. Objective. We set out to investigate the potential roles in PD of single nucleotide polymorphisms (SNPs from one of the key enzymes of the KP, kynurenine 3-monooxygenase (KMO. Methods. 105 unrelated, clinically definitive PD patients and 131 healthy controls were enrolled to investigate the possible effects of the different alleles of KMO. Fluorescently labeled TaqMan probes were used for allele discrimination. Results. None of the four investigated SNPs proved to be associated with PD or influenced the age at onset of the disease. Conclusions. The genetic link between the KP and PD is still missing. The investigated SNPs presumably do not appear to influence the function of KMO and probably do not contain binding sites for regulatory proteins of relevance in PD. This is the first study to assess the genetic background behind the biochemical alterations of the kynurenine pathway in PD, directing the attention to this previously unexamined field.

  13. Serum γ-Glutamyltransferase, Alanine Aminotransferase and Aspartate Aminotransferase Activity in Healthy Blood Donor of Different Ethnic Groups in Gorgan.

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    Marjani, Abdoljalal; Mehrpouya, Masoumeh; Pourhashem, Zeinab

    2016-07-01

    Measure of liver enzymes may help to increase safety of blood donation for both blood donor and recipient. Determination of liver enzymes may prepare valuable clinical information. To assess serum γ-Glutamyltransferase (GGT), Alanine Aminotransferase (ALT), and Aspartate Aminotransferase (AST) activities in healthy blood donors in different ethnic groups in Gorgan. This study was performed in 450 healthy male blood donors, in three ethnic groups (Fars, Sistanee and Turkman) who attended Gorgan blood transfusion center. Liver enzymes (GGT, ALT and AST) were determined. Serum AST and ALT in three ethnic groups were significant except for serum GGT levels. There was significant correlation between family histories of liver disease and systolic blood pressure and AST in Fars, and GGT in Sistanee ethnic groups. Several factors, such as age, family history of diabetes mellitus, family history of liver disease and smoking habit had no effect on some liver enzymes in different ethnic groups in this area. Variation of AST, ALT, and GGT enzyme activities in healthy subjects was associated with some subjects in our study groups. According to our study, it suggests that screening of AST and GGT enzymes in subjects with family history of liver disease is necessary in different ethnic groups.

  14. Aspartate Aminotransferase and Alanine Aminotransferase Detection on Paper-Based Analytical Devices with Inkjet Printer-Sprayed Reagents

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    Hsiang-Li Wang

    2016-01-01

    Full Text Available General biochemistry detection on paper-based microanalytical devices (PADs uses pipette titration. However, such an approach is extremely time-consuming for large-scale detection processes. Furthermore, while automated methods are available for increasing the efficiency of large-scale PAD production, the related equipment is very expensive. Accordingly, this study proposes a low-cost method for PAD manufacture, in which the reagent is applied using a modified inkjet printer. The optimal reaction times for the detection of aspartate aminotransferase (AST and alanine aminotransferase (ALT are shown to be 6 and 7 min, respectively, given AST and ALT concentrations in the range of 5.4 to 91.2 U/L (R2 = 0.9932 and 5.38 to 86.1 U/L (R2 = 0.9944. The experimental results obtained using the proposed PADs for the concentration detection of AST and ALT in real human blood serum samples are found to be in good agreement with those obtained using a traditional spectrophotometric detection method by National Cheng Kung University hospital.

  15. Aminotransferases and Leucine Aminopeptidase Activity in Blood Plasma of Chickens

    International Nuclear Information System (INIS)

    Kraljevic, P.; Stojevic, Z.; Milinkovic-Tur, S.; Simpraga, M.; Miljanic, S.

    1998-01-01

    It has been reported that irradiation of mammals by gama-rays cause increase of some enzyme activity in their blood plasma (Miller and Gates 1949; Milch and Albaum 1959; Hughes 1958; Miholjcic et al. 1979). In our previous papers (Kraljevic et al., 1982; Kraljevic and Emanovic 1993) it has been shown that activities of some enzymes in the blood plasma of chickens after an intramuscular injection of radioactive isotope 32 P. In this paper an attempt has been made to investigate the influence of gamma-ray irradiation of the whole body of chickens upon activity of some enzymes in their blood plasma. We also wanted to investigate whether the activity of aspartate-aminotransferase (AST), alanine aminotransferase (ALT) and leucine-aminopeptidase (LAP) may serve as an additional test for functional liver damage in chickens caused by gamma-ray. Fifty day old hybrid male chickens of heavy Jata breeds were irradiated by gamma-ray in the dose of 7,23±0,95 Gy. Blood samples were taken from the wing vein on days 1, 3, 5, 7, 9 and 15 after irradiation. Activity of AST, ALT, and LAP in the blood plasma were determined spectrophotometrically using Boehringer Mannheim GmbH optimized kits. At the end of the experiment all birds were sacrificed and, as well as died birds were photomorphologically and histologically investigated. The obtained results showed decrease of activity of all three enzymes during the whole period of investigation, but significant decrease showed only AST and LAP. It seems that both enzymes may serve as additional test for functional liver damage in chickens by external gamma-rays. (author)

  16. Central Nervous System Infection with Borna Disease Virus Causes Kynurenine Pathway Dysregulation and Neurotoxic Quinolinic Acid Production.

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    Formisano, Simone; Hornig, Mady; Yaddanapudi, Kavitha; Vasishtha, Mansi; Parsons, Loren H; Briese, Thomas; Lipkin, W Ian; Williams, Brent L

    2017-07-15

    Central nervous system infection of neonatal and adult rats with Borna disease virus (BDV) results in neuronal destruction and behavioral abnormalities with differential immune-mediated involvement. Neuroactive metabolites generated from the kynurenine pathway of tryptophan degradation have been implicated in several human neurodegenerative disorders. Here, we report that brain expression of key enzymes in the kynurenine pathway are significantly, but differentially, altered in neonatal and adult rats with BDV infection. Gene expression analysis of rat brains following neonatal infection showed increased expression of kynurenine amino transferase II (KATII) and kynurenine-3-monooxygenase (KMO) enzymes. Additionally, indoleamine 2,3-dioxygenase (IDO) expression was only modestly increased in a brain region- and time-dependent manner in neonatally infected rats; however, its expression was highly increased in adult infected rats. The most dramatic impact on gene expression was seen for KMO, whose activity promotes the production of neurotoxic quinolinic acid. KMO expression was persistently elevated in brain regions of both newborn and adult BDV-infected rats, with increases reaching up to 86-fold. KMO protein levels were increased in neonatally infected rats and colocalized with neurons, the primary target cells of BDV infection. Furthermore, quinolinic acid was elevated in neonatally infected rat brains. We further demonstrate increased expression of KATII and KMO, but not IDO, in vitro in BDV-infected C6 astroglioma cells. Our results suggest that BDV directly impacts the kynurenine pathway, an effect that may be exacerbated by inflammatory responses in immunocompetent hosts. Thus, experimental models of BDV infection may provide new tools for discriminating virus-mediated from immune-mediated impacts on the kynurenine pathway and their relative contribution to neurodegeneration. IMPORTANCE BDV causes persistent, noncytopathic infection in vitro yet still elicits

  17. Acute Psychological Stress Modulates the Expression of Enzymes Involved in the Kynurenine Pathway throughout Corticolimbic Circuits in Adult Male Rats

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    Haley A. Vecchiarelli

    2016-01-01

    Full Text Available Tryptophan is an essential dietary amino acid that is necessary for protein synthesis, but also serves as the precursor for serotonin. However, in addition to these biological functions, tryptophan also serves as a precursor for the kynurenine pathway, which has neurotoxic (quinolinic acid and neuroprotective (kynurenic acid metabolites. Glucocorticoid hormones and inflammatory mediators, both of which are increased by stress, have been shown to bias tryptophan along the kynurenine pathway and away from serotonin synthesis; however, to date, there is no published data regarding the effects of stress on enzymes regulating the kynurenine pathway in a regional manner throughout the brain. Herein, we examined the effects of an acute psychological stress (120 min restraint on gene expression patterns of enzymes along the kynurenine pathway over a protracted time-course (1–24 h post-stress termination within the amygdala, hippocampus, hypothalamus, and medial prefrontal cortex. Time-dependent changes in differential enzymes along the kynurenine metabolism pathway, particularly those involved in the production of quinolinic acid, were found within the amygdala, hypothalamus, and medial prefrontal cortex, with no changes seen in the hippocampus. These regional differences acutely may provide mechanistic insight into processes that become dysregulated chronically in stress-associated disorders.

  18. Alanine aminotransferase/aspartate aminotransferase ratio is the best surrogate marker for insulin resistance in non-obese Japanese adults

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    Kawamoto Ryuichi

    2012-10-01

    Full Text Available Abstract Background The aim of the present study was to examine how liver markers are associated with insulin resistance in Japanese community-dwelling adults. Methods This cross-sectional study included 587 men aged 58 ± 14 (mean ± standard deviation; range, 20–89 years and 755 women aged 60 ± 12 (range, 21–88 years. The study sample consisted of 998 (74.4% non-obese [body mass index (BMI 2] and 344 (25.6% overweight (BMI ≥25 kg/m2 subjects. Insulin resistance was defined by homeostasis model assessment of insulin resistance (HOMA-IR of at least 2.5, and HOMA-IR and potential confounders were compared between the groups. Areas under the curve (AUC of the receiver operating characteristic curves (ROC were used to compare the power of these serum markers. Results In non-obese subjects, the best marker of insulin resistance was alanine aminotransferase (ALT/aspartate aminotransferase (AST ratio of 0.70 (95% confidence interval (CI, 0.63-0.77. In overweight subjects, AUC values for the ALT/AST ratio and ALT were 0.66 (0.59-0.72 and 0.66 (0.59-0.72, respectively. Multiple linear regression analyses for HOMA-IR showed that ALT/AST ratios were independently and significantly associated with HOMA-IR as well as other confounding factors in both non-obese and overweight subjects. The optimal cut-off point to identifying insulin resistance for these markers yielded the following values: ALT/AST ratio of ≥0.82 in non-obese subjects and ≥1.02 in overweight subjects. In non-obese subjects, the positive likelihood ratio was greatest for ALT/AST ratio. Conclusions In non-obese Japanese adults, ALT/AST ratio may be the best reliable marker of insulin resistance.

  19. Pre-Interventional Kynurenine Predicts Medium-Term Outcome after Contrast Media Exposure Due to Coronary Angiography.

    Science.gov (United States)

    Reichetzeder, Christoph; Heunisch, Fabian; Einem, Gina von; Tsuprykov, Oleg; Kellner, Karl-Heinz; Dschietzig, Thomas; Kretschmer, Axel; Hocher, Berthold

    2017-01-01

    Contrast induced acute kidney injury (CI-AKI) remains a serious complication of contrast media enhanced procedures like coronary angiography. There is still a lack of established biomarkers that help to identify patients at high risk for short and long-term complications. The aim of the current study was to evaluate plasma kynurenine as a predictive biomarker for CI-AKI and long-term complications, measured by the combined endpoint "major adverse kidney events" (MAKE) up to 120 days after CM application. In this prospective cohort study 245 patients undergoing coronary angiography were analyzed. Blood samples were obtained at baseline, 24h and 48h after contrast media (CM) application to diagnose CI-AKI. Patients were followed for 120 days for adverse clinical events including death, the need for dialysis, and a doubling of plasma creatinine. Occurrence of any of these events was summarized in the combined endpoint MAKE. Preinterventional plasma kynurenine was not associated with CI-AKI. Patients who later developed MAKE displayed significantly increased preinterventional plasma kynurenine levels (p<0.0001). ROC analysis revealed that preinterventional kynurenine is highly predictive for MAKE (AUC=0.838; p<0.0001). The optimal cutoff was found at ≥3.5 µmol/L Using this cutoff, the Kaplan-Meier estimator demonstrated that concentrations of plasma kynurenine ≥3.5 µmol/L were significantly associated with a higher prevalence of MAKE until follow up (p<0.0001). This association remained significant in multivariate Cox regression models adjusted for relevant factors of long-term renal outcome. Preinterventional plasma kynurenine might serve as a highly predictive biomarker for MAKE up to 120 days after coronary angiography. © 2017 The Author(s). Published by S. Karger AG, Basel.

  20. Pre-Interventional Kynurenine Predicts Medium-Term Outcome after Contrast Media Exposure Due to Coronary Angiography

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    Christoph Reichetzeder

    2017-05-01

    Full Text Available Background/Aims: Contrast induced acute kidney injury (CI-AKI remains a serious complication of contrast media enhanced procedures like coronary angiography. There is still a lack of established biomarkers that help to identify patients at high risk for short and long-term complications. The aim of the current study was to evaluate plasma kynurenine as a predictive biomarker for CI-AKI and long-term complications, measured by the combined endpoint "major adverse kidney events" (MAKE up to 120 days after CM application. Methods: In this prospective cohort study 245 patients undergoing coronary angiography were analyzed. Blood samples were obtained at baseline, 24h and 48h after contrast media (CM application to diagnose CI-AKI. Patients were followed for 120 days for adverse clinical events including death, the need for dialysis, and a doubling of plasma creatinine. Occurrence of any of these events was summarized in the combined endpoint MAKE. Results: Preinterventional plasma kynurenine was not associated with CI-AKI. Patients who later developed MAKE displayed significantly increased preinterventional plasma kynurenine levels (p<0.0001. ROC analysis revealed that preinterventional kynurenine is highly predictive for MAKE (AUC=0.838; p<0.0001. The optimal cutoff was found at ≥3.5 µmol/L Using this cutoff, the Kaplan-Meier estimator demonstrated that concentrations of plasma kynurenine ≥3.5 µmol/L were significantly associated with a higher prevalence of MAKE until follow up (p<0.0001. This association remained significant in multivariate Cox regression models adjusted for relevant factors of long-term renal outcome. Conclusion: Preinterventional plasma kynurenine might serve as a highly predictive biomarker for MAKE up to 120 days after coronary angiography.

  1. Serum concentrations of kynurenines in adult patients with attention-deficit hyperactivity disorder (ADHD): a case-control study.

    Science.gov (United States)

    Aarsland, Tore Ivar Malmei; Landaas, Elisabeth Toverud; Hegvik, Tor-Arne; Ulvik, Arve; Halmøy, Anne; Ueland, Per Magne; Haavik, Jan

    2015-11-05

    The essential amino acid tryptophan is catabolised mainly through the kynurenine pathway. Altered circulating levels of kynurenines have been reported in chronic inflammatory conditions and in several neuropsychiatric disorders, including depression and schizophrenia. Candidate gene studies suggest that genes related to the kynurenine catabolism may be associated with attention-deficit hyperactivity disorder (ADHD). Additionally, ADHD patients often report comorbid depression or anxiety. In this study we investigated serum levels of kynurenines in Norwegian adult ADHD patients and adult controls. We compared serum levels of tryptophan and the seven tryptophan metabolites kynurenine, kynurenic acid, anthranilic acid, 3-hydroxykynurenine, xanthurenic acid, 3-hydroxyanthranilic acid and quinolinic acid in 133 adult patients with ADHD and 131 adult controls (18-40 years). Riboflavin (vitamin B2), total vitamin B6 and the nicotine metabolite cotinine were also measured. Serum samples were analysed using mass spectrometry. Patients and controls reported comorbid disorders and past (childhood) and current ADHD symptoms using the Wender Utah Rating Scale (WURS) and the Adult ADHD Self-report Scale (ASRS). Logistic regression was used to calculate odds ratios for having an ADHD diagnosis for different serum levels of each metabolite. In addition, we used Spearman's correlation analysis to investigate the correlation between serum levels of tryptophan and kynurenines and ADHD symptom scores. Lower serum concentrations of tryptophan [odds ratio 0.61 (95 % confidence interval 0.45-0.83)], kynurenic acid [0.73 (0.53-0.99)], xanthurenic acid [0.65 (0.48-0.89)] and 3-hydroxyanthranilic acid [0.63 (0.46-0.85)], and higher levels of cotinine [7.17 (4.37-12.58)], were significantly associated with ADHD. After adjusting for tryptophan levels, only 3-hydroxyanthranilic acid and cotinine remained significant. Lower levels of tryptophan and kynurenine were also found to be correlated

  2. Ambient Ionization Mass Spectrometry Measurement of Aminotransferase Activity

    Science.gov (United States)

    Yan, Xin; Li, Xin; Zhang, Chengsen; Xu, Yang; Cooks, R. Graham

    2017-06-01

    A change in enzyme activity has been used as a clinical biomarker for diagnosis and is useful in evaluating patient prognosis. Current laboratory measurements of enzyme activity involve multi-step derivatization of the reaction products followed by quantitative analysis of these derivatives. This study simplified the reaction systems by using only the target enzymatic reaction and directly detecting its product. A protocol using paper spray mass spectrometry for identifying and quantifying the reaction product has been developed. Evaluation of the activity of aspartate aminotransferase (AST) was chosen as a proof-of-principle. The volume of sample needed is greatly reduced compared with the traditional method. Paper spray has a desalting effect that avoids sprayer clogging problems seen when examining serum samples by nanoESI. This very simple method does not require sample pretreatment and additional derivatization reactions, yet it gives high quality kinetic data, excellent limits of detection (60 ppb from serum), and coefficients of variation <10% in quantitation. [Figure not available: see fulltext.

  3. Tyrosine aminotransferase from Leishmania infantum: A new drug target candidate

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    Miguel Angel Moreno

    2014-12-01

    Full Text Available Leishmania infantum is the etiological agent of zoonotic visceral leishmaniasis in the Mediterranean basin. The disease is fatal without treatment, which has been based on antimonial pentavalents for more than 60 years. Due to resistances, relapses and toxicity to current treatment, the development of new drugs is required. The structure of the L. infantum tyrosine aminotransferase (LiTAT has been recently solved showing important differences with the mammalian orthologue. The characterization of LiTAT is reported herein. This enzyme is cytoplasmic and is over-expressed in the more infective stages and nitric oxide resistant parasites. Unlike the mammalian TAT, LiTAT is able to use ketomethiobutyrate as co-substrate. The pharmacophore model of LiTAT with this specific co-substrate is described herein. This may allow the identification of new inhibitors present in the databases. All the data obtained support that LiTAT is a good target candidate for the development of new anti-leishmanial drugs.

  4. Multiphoton manipulations of enzymatic photoactivity in aspartate aminotransferase.

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    Hill, Melissa P; Freer, Lucy H; Vang, Mai C; Carroll, Elizabeth C; Larsen, Delmar S

    2011-04-21

    The aspartate aminotransferase (AAT) enzyme utilizes the chromophoric pyridoxal 5'-phosphate (PLP) cofactor to facilitate the transamination of amino acids. Recently, we demonstrated that, upon exposure to blue light, PLP forms a reactive triplet state that rapidly (in microseconds) generates the high-energy quinonoid intermediate when bound to PLP-dependent enzymes [J. Am. Chem. Soc.2010, 132 (47), 16953-16961]. This increases the net catalytic activity (k(cat)) of AAT, since formation of the quinonoid is partially rate limiting via the thermally activated enzymatic pathway. The magnitude of observed photoenhancement initially scales linearly with pump fluence; however when a critical threshold is exceeded, the photoactivity saturates and is even suppressed at greater excitation fluences. The photodynamic mechanisms associated with this suppression behavior are characterized with the use of ultrafast multipulse pump-dump-probe and pump-repump-probe transient absorption techniques in combination with complementary two-color, steady-state excitation assays. Via multistate kinetic modeling of the transient ultrafast data and the steady-state assay data, the nonmonotonic incident power dependence of the photoactivty in AAT is decomposed into contributions from high-intensity dumping of the excited singlet state and repumping of the excited triplet state with induces the repopulation of the ground state via rapid intersystem crossing in the higher-lying triplet electronic manifold.

  5. Changes in kynurenine pathway metabolism in Parkinson patients with L-DOPA-induced dyskinesia.

    Science.gov (United States)

    Havelund, Jesper F; Andersen, Andreas D; Binzer, Michael; Blaabjerg, Morten; Heegaard, Niels H H; Stenager, Egon; Faergeman, Nils J; Gramsbergen, Jan Bert

    2017-09-01

    L-3,4-Dihydroxyphenylalanine (L-DOPA) is the most effective drug in the symptomatic treatment of Parkinson's disease, but chronic use is associated with L-DOPA-induced dyskinesia in more than half the patients after 10 years of treatment. L-DOPA treatment may affect tryptophan metabolism via the kynurenine pathway. Altered levels of kynurenine metabolites can affect glutamatergic transmission and may play a role in the development of L-DOPA-induced dyskinesia. In this study, we assessed kynurenine metabolites in plasma and cerebrospinal fluid of Parkinson's disease patients and controls. Parkinson patients (n = 26) were clinically assessed for severity of motor symptoms (UPDRS) and L-DOPA-induced dyskinesia (UDysRS). Plasma and cerebrospinal fluid samples were collected after overnight fasting and 1-2 h after intake of L-DOPA or other anti-Parkinson medication. Metabolites were analyzed in plasma and cerebrospinal fluid of controls (n = 14), Parkinson patients receiving no L-DOPA (n = 8), patients treated with L-DOPA without dyskinesia (n = 8), and patients with L-DOPA-induced dyskinesia (n = 10) using liquid chromatography-mass spectrometry. We observed approximately fourfold increase in the 3-hydroxykynurenine/kynurenic acid ratio in plasma of Parkinson's patients with L-DOPA-induced dyskinesia. Anthranilic acid levels were decreased in plasma and cerebrospinal fluid of this patient group. 5-Hydroxytryptophan levels were twofold increased in all L-DOPA-treated Parkinson's patients. We conclude that a higher 3-hydroxykynurenine/kynurenic acid ratio in plasma may serve as a biomarker for L-DOPA-induced dyskinesia. Longitudinal studies including larger patients cohorts are needed to verify whether the changes observed here may serve as a prognostic marker for L-DOPA-induced dyskinesia. © 2017 International Society for Neurochemistry.

  6. HMGB1 mediates depressive behavior induced by chronic stress through activating the kynurenine pathway.

    Science.gov (United States)

    Wang, Bo; Lian, Yong-Jie; Su, Wen-Jun; Peng, Wei; Dong, Xin; Liu, Lin-Lin; Gong, Hong; Zhang, Ting; Jiang, Chun-Lei; Wang, Yun-Xia

    2017-11-28

    Our previous study has reported that the proactive secretion and role of central high mobility group box 1 (HMGB1) in lipopolysaccharide-induced depressive behavior. Here, the potential mechanism of HMGB1 mediating chronic-stress-induced depression through the kynurenine pathway (KP) was further explored both in vivo and in vitro. Depression model was established with the 4-week chronic unpredictable mild stress (CUMS). Sucrose preference and Barnes maze test were performed to reflect depressive behaviors. The ratio of kynurenine (KYN)/tryptophan (Trp) represented the enzyme activity of indoleamine-2,3-dioxygenase (IDO). Gene transcription and protein expression were assayed by real-time RT-PCR and western-blot or ELISA kit respectively. Along with depressive behaviors, HMGB1 concentrations in the hippocampus and serum substantially increased post 4-week CUMS exposure. Concurrent with the upregulated HMGB1 protein, the regulator of translocation of HMGB1, sirtuin 1 (SIRT1) concentration in the hippocampus remarkably increased. In addition to HMGB1 and SIRT1, IDO, the rate limiting enzyme of KP, was upregulated at the level of mRNA expression and enzyme activity in stressed hippocampi and LPS/HMGB1-treated hippocampal slices. The gene transcription of kynurenine monooxygenase (KMO) and kynureninase (KYNU) in the downstream of KP also increased both in vivo and in vitro. Mice treated with ethyl pyruvate (EP), the inhibitor of HMGB1 releasing, were observed with lower tendency of developing depressive behaviors and reduced activation of enzymes in KP. All of these experiments demonstrate that the role of HMGB1 on the induction of depressive behavior is mediated by KP activation. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Pharmacological kynurenine 3-monooxygenase enzyme inhibition significantly reduces neuropathic pain in a rat model.

    Science.gov (United States)

    Rojewska, Ewelina; Piotrowska, Anna; Makuch, Wioletta; Przewlocka, Barbara; Mika, Joanna

    2016-03-01

    Recent studies have highlighted the involvement of the kynurenine pathway in the pathology of neurodegenerative diseases, but the role of this system in neuropathic pain requires further extensive research. Therefore, the aim of our study was to examine the role of kynurenine 3-monooxygenase (Kmo), an enzyme that is important in this pathway, in a rat model of neuropathy after chronic constriction injury (CCI) to the sciatic nerve. For the first time, we demonstrated that the injury-induced increase in the Kmo mRNA levels in the spinal cord and the dorsal root ganglia (DRG) was reduced by chronic administration of the microglial inhibitor minocycline and that this effect paralleled a decrease in the intensity of neuropathy. Further, minocycline administration alleviated the lipopolysaccharide (LPS)-induced upregulation of Kmo mRNA expression in microglial cell cultures. Moreover, we demonstrated that not only indirect inhibition of Kmo using minocycline but also direct inhibition using Kmo inhibitors (Ro61-6048 and JM6) decreased neuropathic pain intensity on the third and the seventh days after CCI. Chronic Ro61-6048 administration diminished the protein levels of IBA-1, IL-6, IL-1beta and NOS2 in the spinal cord and/or the DRG. Both Kmo inhibitors potentiated the analgesic properties of morphine. In summary, our data suggest that in neuropathic pain model, inhibiting Kmo function significantly reduces pain symptoms and enhances the effectiveness of morphine. The results of our studies show that the kynurenine pathway is an important mediator of neuropathic pain pathology and indicate that Kmo represents a novel pharmacological target for the treatment of neuropathy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Biochemistry and structural studies of kynurenine 3-monooxygenase reveal allosteric inhibition by Ro 61-8048.

    Science.gov (United States)

    Gao, Jingjing; Yao, Licheng; Xia, Tingting; Liao, Xuebin; Zhu, Deyu; Xiang, Ye

    2018-04-01

    The human kynurenine 3-monooxygenase (hKMO) is a potential therapeutic target for neurodegenerative and neurologic disorders. Inhibition of KMO by Ro 61-8048, a potent, selective, and the most widely used inhibitor of KMO, was shown effective in various models of neurodegenerative or neurologic disorders. However, the molecular basis of hKMO inhibition by Ro 61-8048 is not clearly understood. Here, we report biochemistry studies on hKMO and crystal structures of an hKMO homolog, pfKMO from Pseudomonas fluorescens, in complex with the substrate l-kynurenine and Ro 61-8048. We found that the C-terminal ∼110 aa are essential for the enzymatic activity of hKMO and the homologous C-terminal region of pfKMO folds into a distinct, all-α-helical domain, which associates with the N-terminal catalytic domain to form a unique tunnel in proximity to the substrate-binding pocket. The tunnel binds the Ro 61-8048 molecule, which fills most of the tunnel, and Ro 61-8048 is hydrogen bonded with several completely conserved residues, including an essential catalytic residue. Modification of Ro 61-8048 and biochemical studies of the modified Ro 61-8048 derivatives suggested that Ro 61-8048 inhibits the enzyme in an allosteric manner by affecting the conformation of the essential catalytic residue and by blocking entry of the substrate or product release. The unique binding sites distinguish Ro 61-8048 as a noncompetitive and highly selective inhibitor from other competitive inhibitors, which should facilitate further optimization of Ro 61-8048 and the development of new inhibitory drugs to hKMO.-Gao, J., Yao, L., Xia, T., Liao, X., Zhu, D., Xiang, Y. Biochemistry and structural studies of kynurenine 3-monooxygenase reveal allosteric inhibition by Ro 61-8048.

  9. Increasing kynurenine brain levels reduces ethanol consumption in mice by inhibiting dopamine release in nucleus accumbens.

    Science.gov (United States)

    Giménez-Gómez, Pablo; Pérez-Hernández, Mercedes; Gutiérrez-López, María Dolores; Vidal, Rebeca; Abuin-Martínez, Cristina; O'Shea, Esther; Colado, María Isabel

    2018-06-01

    Recent research suggests that ethanol (EtOH) consumption behaviour can be regulated by modifying the kynurenine (KYN) pathway, although the mechanisms involved have not yet been well elucidated. To further explore the implication of the kynurenine pathway in EtOH consumption we inhibited kynurenine 3-monooxygenase (KMO) activity with Ro 61-8048 (100 mg/kg, i.p.), which shifts the KYN metabolic pathway towards kynurenic acid (KYNA) production. KMO inhibition decreases voluntary binge EtOH consumption and EtOH preference in mice subjected to "drinking in the dark" (DID) and "two-bottle choice" paradigms, respectively. This effect seems to be a consequence of increased KYN concentration, since systemic KYN administration (100 mg/kg, i.p.) similarly deters binge EtOH consumption in the DID model. Despite KYN and KYNA being well-established ligands of the aryl hydrocarbon receptor (AhR), administration of AhR antagonists (TMF 5 mg/kg and CH-223191 20 mg/kg, i.p.) and of an agonist (TCDD 50 μg/kg, intragastric) demonstrates that signalling through this receptor is not involved in EtOH consumption behaviour. Ro 61-8048 did not alter plasma acetaldehyde concentration, but prevented EtOH-induced dopamine release in the nucleus accumbens shell. These results point to a critical involvement of the reward circuitry in the reduction of EtOH consumption induced by KYN and KYNA increments. PNU-120596 (3 mg/kg, i.p.), a positive allosteric modulator of α7-nicotinic acetylcholine receptors, partially prevented the Ro 61-8048-induced decrease in EtOH consumption. Overall, our results highlight the usefulness of manipulating the KYN pathway as a pharmacological tool for modifying EtOH consumption and point to a possible modulator of alcohol drinking behaviour. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Neopterin, kynurenine and tryptophan as new biomarkers for early detection of rectal anastomotic leakage.

    Science.gov (United States)

    Dusek, Tomas; Orhalmi, Julius; Sotona, Otakar; Krcmova, Lenka Kujovska; Javorska, Lenka; Dolejs, Josef; Paral, Jiri

    2018-03-01

    At present, there are no strong predictors, nor a useful scoring system, that clearly identifies patients at risk for anastomotic leakage. This study aimed to investigate a new method that assesses this risk by monitoring levels of neopterin, tryptophan, and kynurenine, in bodily fluids. This prospective study included patients who underwent elective rectal resection for carcinoma. The basic condition for inclusion was rectal anastomosis using the double-stapling technique. Preoperative levels of neopterin, tryptophan, kynurenine, and their ratios, were assessed with blood and urine samples. These levels were then monitored for 6 postoperative days in venous blood, urine, and abdominal drainage fluid. A total of 42 patients were enrolled in the study. Thirty-six patients underwent a laparoscopic resection and 6 patients had an open procedure. No differences were found among neopterin, tryptophan, and kynurenine serum levels. However, the groups were observed to have significant differences in the urinary neopterin/creatinine ratio: the preoperative neopterin/creatinine ratio was 139.5 μmol/mol in the group with leakage, vs 114.8 μmol/mol in the group without complications, p = 0.037. The same results were observed during the postoperative period, p = 0.012. Additionally, the group with complications had a higher mean value of neopterin in drainage fluid, p = 0.048. Our study demonstrated that high preoperative levels of urinary neopterin could be interpreted as a risk for anastomotic leakage. Moreover, pathological levels of neopterin in urine and abdominal drainage fluid could be useful for early identification of anastomotic leakage during the postoperative period prior to its clinical development.

  11. Tyrosine aminotransferase contributes to benzylisoquinoline alkaloid biosynthesis in opium poppy.

    Science.gov (United States)

    Lee, Eun-Jeong; Facchini, Peter J

    2011-11-01

    Tyrosine aminotransferase (TyrAT) catalyzes the transamination of L-Tyr and α-ketoglutarate, yielding 4-hydroxyphenylpyruvic acid and L-glutamate. The decarboxylation product of 4-hydroxyphenylpyruvic acid, 4-hydroxyphenylacetaldehyde, is a precursor to a large and diverse group of natural products known collectively as benzylisoquinoline alkaloids (BIAs). We have isolated and characterized a TyrAT cDNA from opium poppy (Papaver somniferum), which remains the only commercial source for several pharmaceutical BIAs, including codeine, morphine, and noscapine. TyrAT belongs to group I pyridoxal 5'-phosphate (PLP)-dependent enzymes wherein Schiff base formation occurs between PLP and a specific Lys residue. The amino acid sequence of TyrAT showed considerable homology to other putative plant TyrATs, although few of these have been functionally characterized. Purified, recombinant TyrAT displayed a molecular mass of approximately 46 kD and a substrate preference for L-Tyr and α-ketoglutarate, with apparent K(m) values of 1.82 and 0.35 mm, respectively. No specific requirement for PLP was detected in vitro. Liquid chromatography-tandem mass spectrometry confirmed the conversion of L-Tyr to 4-hydroxyphenylpyruvate. TyrAT gene transcripts were most abundant in roots and stems of mature opium poppy plants. Virus-induced gene silencing was used to evaluate the contribution of TyrAT to BIA metabolism in opium poppy. TyrAT transcript levels were reduced by at least 80% in silenced plants compared with controls and showed a moderate reduction in total alkaloid content. The modest correlation between transcript levels and BIA accumulation in opium poppy supports a role for TyrAT in the generation of alkaloid precursors, but it also suggests the occurrence of other sources for 4-hydroxyphenylacetaldehyde.

  12. Alanine aminotransferase variants conferring diverse NUE phenotypes in Arabidopsis thaliana.

    Science.gov (United States)

    McAllister, Chandra H; Good, Allen G

    2015-01-01

    Alanine aminotransferase (AlaAT, E.C. 2.6.1.2), is a pyridoxal-5'-phosphate-dependent (PLP) enzyme that catalyzes the reversible transfer of an amino group from alanine to 2-oxoglutarate to produce glutamate and pyruvate, or vice versa. It has been well documented in both greenhouse and field studies that tissue-specific over-expression of AlaAT from barley (Hordeum vulgare, HvAlaAT) results in a significant increase in plant NUE in both canola and rice. While the physical phenotypes associated with over-expression of HvAlaAT have been well characterized, the role this enzyme plays in vivo to create a more N efficient plant remains unknown. Furthermore, the importance of HvAlaAT, in contrast to other AlaAT enzyme homologues in creating this phenotype has not yet been explored. To address the role of AlaAT in NUE, AlaAT variants from diverse sources and different subcellular locations, were expressed in the wild-type Arabidopsis thaliana Col-0 background and alaat1;2 (alaat1-1;alaat2-1) knockout background in various N environments. The analysis and comparison of both the physical and physiological properties of AlaAT over-expressing transgenic plants demonstrated significant differences between plants expressing the different AlaAT enzymes under different external conditions. This analysis indicates that the over-expression of AlaAT variants other than HvAlaAT in crop plants could further increase the NUE phenotype(s) previously observed.

  13. Sensitive non-radioactive determination of aminotransferase stereospecificity for C-4' hydrogen transfer on the coenzyme.

    Science.gov (United States)

    Jomrit, Juntratip; Summpunn, Pijug; Meevootisom, Vithaya; Wiyakrutta, Suthep

    2011-02-25

    A sensitive non-radioactive method for determination of the stereospecificity of the C-4' hydrogen transfer on the coenzymes (pyridoxal phosphate, PLP; and pyridoxamine phosphate, PMP) of aminotransferases has been developed. Aminotransferase of unknown stereospecificity in its PLP form was incubated in (2)H(2)O with a substrate amino acid resulted in PMP labeled with deuterium at C-4' in the pro-S or pro-R configuration according to the stereospecificity of the aminotransferase tested. The [4'-(2)H]PMP was isolated from the enzyme protein and divided into two portions. The first portion was incubated in aqueous buffer with apo-aspartate aminotransferase (a reference si-face specific enzyme), and the other was incubated with apo-branched-chain amino acid aminotransferase (a reference re-face specific enzyme) in the presence of a substrate 2-oxo acid. The (2)H at C-4' is retained with the PLP if the aminotransferase in question transfers C-4' hydrogen on the opposite face of the coenzyme compared with the reference aminotransferase, but the (2)H is removed if the test and reference aminotransferases catalyze hydrogen transfer on the same face. PLP formed in the final reactions was analyzed by LC-MS/MS for the presence or absence of (2)H. The method was highly sensitive that for the aminotransferase with ca. 50 kDa subunit molecular weight, only 2mg of the enzyme was sufficient for the whole test. With this method, the use of radioactive substances could be avoided without compromising the sensitivity of the assay. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Serum alanine aminotransferase levels, hematocrit rate and body weight correlations before and after hemodialysis session

    Directory of Open Access Journals (Sweden)

    Edmundo Pessoa Lopes

    2009-01-01

    Full Text Available PURPOSE: To evaluate alanine aminotransferase levels before and after a hemodialysis session and to correlate these values with the hematocrit rate and weight loss during hemodialysis. PATIENTS AND METHODS: The serum alanine aminotransferase levels, hematocrit rate and body weight were measured and correlated before and after a single hemodialysis session for 146 patients with chronic renal failure. An receiver operating characteristic (ROC curve for the serum alanine aminotransferase levels collected before and after hemodialysis was plotted to identify hepatitis C virus-infected patients. RESULTS: The mean weight loss of the 146 patients during hemodialysis was 5.3% (p < 0.001. The mean alanine aminotransferase levels before and after hemodialysis were 18.8 and 23.9 IU/, respectively, denoting a significant 28.1% increase. An equally significant increase of 16.4% in the hematocrit rate also occurred after hemodialysis. The weight loss was inversely correlated with the rise in both the alanine aminotransferase level (r = 0.3; p < 0.001 and hematocrit rate (r = 0.5; p < 0.001. A direct correlation was found between the rise in alanine aminotransferase levels and the hematocrit during the hemodialysis session (r = 0.4; p < 0.001. Based on the ROC curve, the upper limit of the normal alanine aminotransferase level should be reduced by 40% relative to the upper limit of normal if the blood samples are collected before the hemodialysis session or by 60% if blood samples are collected after the session. CONCLUSION: In the present study, significant elevations in the serum alanine aminotransferase levels and hematocrit rates occurred in parallel to a reduction in body weight after the hemodialysis session. These findings suggest that one of the factors for low alanine aminotransferase levels prior to hemodialysis could be hemodilution in patients with chronic renal failure.

  15. The Kynurenine Pathway Modulates Neurodegeneration in a Drosophila Model of Huntington’s Disease

    Science.gov (United States)

    Campesan, Susanna; Green, Edward W.; Breda, Carlo; Sathyasaikumar, Korrapati V.; Muchowski, Paul J.; Schwarcz, Robert; Kyriacou, Charalambos P.; Giorgini, Flaviano

    2014-01-01

    Summary Neuroactive metabolites of the kynurenine pathway (KP) of tryptophan degradation have been implicated in the pathophysiology of neurodegenerative disorders, including Huntington’s disease (HD) [1]. A central hallmark of HD is neurodegeneration caused by a polyglutamine expansion in the huntingtin (htt) protein [2]. Here we exploit a transgenic Drosophila melanogaster model of HD to interrogate the therapeutic potential of KP manipulation. We observe that genetic and pharmacological inhibition of kynurenine 3-monooxygenase (KMO) increases levels of the neuroprotective metabolite kynurenic acid (KYNA) relative to the neurotoxic metabolite 3-hydroxykynurenine (3-HK) and ameliorates neurodegeneration. We also find that genetic inhibition of tryptophan 2,3-dioxygenase (TDO), the first and rate-limiting step in the pathway, leads to a similar neuroprotective shift toward KYNA synthesis. Importantly, we demonstrate that the feeding of KYNA and 3-HK to HD model flies directly modulates neurodegeneration, underscoring the causative nature of these metabolites. This study provides the first genetic evidence that inhibition of KMO and TDO activity protects against neurodegenerative disease in an animal model, indicating that strategies targeted at two key points within the KP may have therapeutic relevance in HD, and possibly other neurodegenerative disorders. PMID:21636279

  16. Kynurenine pathway and cognitive impairments in schizophrenia: Pharmacogenetics of galantamine and memantine

    Directory of Open Access Journals (Sweden)

    Maju Mathew Koola

    2016-06-01

    Full Text Available The Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS project designed to facilitate the development of new drugs for the treatment of cognitive impairments in people with schizophrenia, identified three drug mechanisms of particular interest: dopaminergic, cholinergic, and glutamatergic. Galantamine is an acetylcholinesterase inhibitor and a positive allosteric modulator of the α7 nicotinic receptors. Memantine is an N-methyl-D-aspartate (NMDA receptor antagonist. There is evidence to suggest that the combination of galantamine and memantine may be effective in the treatment of cognitive impairments in schizophrenia. There is a growing body of evidence that excess kynurenic acid (KYNA is associated with cognitive impairments in schizophrenia. The α-7 nicotinic and the NMDA receptors may counteract the effects of kynurenic acid (KYNA resulting in cognitive enhancement. Galantamine and memantine through its α-7 nicotinic and NMDA receptors respectively may counteract the effects of KYNA thereby improving cognitive impairments. The Single Nucleotide Polymorphisms in the Cholinergic Receptor, Nicotinic, Alpha 7 gene (CHRNA7, Glutamate (NMDA Receptor, Metabotropic 1 (GRM1 gene, Dystrobrevin Binding Protein 1 (DTNBP1 and kynurenine 3-monooxygenase (KMO gene may predict treatment response to galantamine and memantine combination for cognitive impairments in schizophrenia in the kynurenine pathway.

  17. Targeting kynurenine 3-monooxygenase (KMO): implications for therapy in Huntington's disease.

    Science.gov (United States)

    Thevandavakkam, Mathuravani A; Schwarcz, Robert; Muchowski, Paul J; Giorgini, Flaviano

    2010-12-01

    Huntington's disease (HD) is an adult onset neurodegenerative disease caused by a polyglutamine expansion in the huntingtin protein. Recent work has shown that perturbation of kynurenine pathway (KP) metabolism is a hallmark of HD pathology, and that changes in brain levels of KP metabolites may play a causative role in this disease. The KP contains three neuroactive metabolites, the neurotoxins 3-hydroxykynurenine (3-HK) and quinolinic acid (QUIN), and the neuroprotectant kynurenic acid (KYNA). In model systems in vitro and in vivo, 3-HK and QUIN have been shown to cause neurodegeneration via a combination of excitotoxic mechanisms and oxidative stress. Recent studies with HD patient samples and in HD model systems have supported the idea that a shift away from the synthesis of KYNA and towards the formation of 3-HK and QUIN may trigger the neuropathological features observed in HD. The enzyme kynurenine 3-monooxygenase (KMO) is located at a critical branching point in the KP such that inhibition of this enzyme by either pharmacological or genetic means shifts the flux in the pathway towards the formation of KYNA. This intervention ameliorates disease-relevant phenotypes in HD models. Here we review the work implicating the KP in HD pathology and discuss the potential of KMO as a therapeutic target for this disorder. As several neurodegenerative diseases exhibit alterations in KP metabolism, this concept has broader implications for the treatment of brain diseases.

  18. Tryptophan-2,3-dioxygenase (TDO) inhibition ameliorates neurodegeneration by modulation of kynurenine pathway metabolites.

    Science.gov (United States)

    Breda, Carlo; Sathyasaikumar, Korrapati V; Sograte Idrissi, Shama; Notarangelo, Francesca M; Estranero, Jasper G; Moore, Gareth G L; Green, Edward W; Kyriacou, Charalambos P; Schwarcz, Robert; Giorgini, Flaviano

    2016-05-10

    Metabolites of the kynurenine pathway (KP) of tryptophan (TRP) degradation have been closely linked to the pathogenesis of several neurodegenerative disorders. Recent work has highlighted the therapeutic potential of inhibiting two critical regulatory enzymes in this pathway-kynurenine-3-monooxygenase (KMO) and tryptophan-2,3-dioxygenase (TDO). Much evidence indicates that the efficacy of KMO inhibition arises from normalizing an imbalance between neurotoxic [3-hydroxykynurenine (3-HK); quinolinic acid (QUIN)] and neuroprotective [kynurenic acid (KYNA)] KP metabolites. However, it is not clear if TDO inhibition is protective via a similar mechanism or if this is instead due to increased levels of TRP-the substrate of TDO. Here, we find that increased levels of KYNA relative to 3-HK are likely central to the protection conferred by TDO inhibition in a fruit fly model of Huntington's disease and that TRP treatment strongly reduces neurodegeneration by shifting KP flux toward KYNA synthesis. In fly models of Alzheimer's and Parkinson's disease, we provide genetic evidence that inhibition of TDO or KMO improves locomotor performance and ameliorates shortened life span, as well as reducing neurodegeneration in Alzheimer's model flies. Critically, we find that treatment with a chemical TDO inhibitor is robustly protective in these models. Consequently, our work strongly supports targeting of the KP as a potential treatment strategy for several major neurodegenerative disorders and suggests that alterations in the levels of neuroactive KP metabolites could underlie several therapeutic benefits.

  19. Development of LC/MS/MS, high-throughput enzymatic and cellular assays for the characterization of compounds that inhibit kynurenine monooxygenase (KMO).

    Science.gov (United States)

    Winkler, Dirk; Beconi, Maria; Toledo-Sherman, Leticia M; Prime, Michael; Ebneth, Andreas; Dominguez, Celia; Muñoz-Sanjuan, Ignacio

    2013-09-01

    Kynurenine monooxygenase (KMO) catalyzes the conversion of kynurenine to 3-hydroxykynurenine. Modulation of KMO activity has been implicated in several neurodegenerative diseases, including Huntington disease. Our goal is to develop potent and selective small-molecule KMO inhibitors with suitable pharmacokinetic characteristics for in vivo proof-of-concept studies and subsequent clinical development. We developed a comprehensive panel of biochemical and cell-based assays that use liquid chromatography/tandem mass spectrometry to quantify unlabeled kynurenine and 3-hydroxykynurenine. We describe assays to measure KMO inhibition in cell and tissue extracts, as well as cellular assays including heterologous cell lines and primary rat microglia and human peripheral blood mononuclear cells.

  20. Importance of kynurenine 3-monooxygenase for spontaneous firing and pharmacological responses of midbrain dopamine neurons: Relevance for schizophrenia.

    Science.gov (United States)

    Tufvesson-Alm, Maximilian; Schwieler, Lilly; Schwarcz, Robert; Goiny, Michel; Erhardt, Sophie; Engberg, Göran

    2018-06-05

    Kynurenine 3-monooxygenase (KMO) is an essential enzyme of the kynurenine pathway, converting kynurenine into 3-hydroxykynurenine. Inhibition of KMO increases kynurenine, resulting in elevated levels of kynurenic acid (KYNA), an endogenous N-methyl-d-aspartate and α*7-nicotinic receptor antagonist. The concentration of KYNA is elevated in the brain of patients with schizophrenia, possibly as a result of a reduced KMO activity. In the present study, using in vivo single cell recording techniques, we investigated the electrophysiological characteristics of ventral tegmental area dopamine (VTA DA) neurons and their response to antipsychotic drugs in a KMO knock-out (K/O) mouse model. KMO K/O mice exhibited a marked increase in spontaneous VTA DA neuron activity as compared to wild-type (WT) mice. Furthermore, VTA DA neurons showed clear-cut, yet qualitatively opposite, responses to the antipsychotic drugs haloperidol and clozapine in the two genotypes. The anti-inflammatory drug parecoxib successfully lowered the firing activity of VTA DA neurons in KMO K/O, but not in WT mice. Minocycline, an antibiotic and anti-inflammatory drug, produced no effect in this regard. Taken together, the present data further support the usefulness of KMO K/O mice for studying distinct aspects of the pathophysiology and pharmacological treatment of psychiatric disorders such as schizophrenia. Copyright © 2018. Published by Elsevier Ltd.

  1. Characterization of Potential Antimicrobial Targets in Bacillus spp. II. Branched-Chain Aminotransferase and Methionine Regeneration in B. cereus and B. anthracis

    National Research Council Canada - National Science Library

    Berger, B

    2002-01-01

    .... Four putative family III aminotransferases, two with homology to branched-chain amino acid aminotransferases and two with homology to D- amino acid aminotransferases, were cloned from B. cereus...

  2. Relationship between neurotoxic kynurenine metabolites and reductions in right medial prefrontal cortical thickness in major depressive disorder.

    Science.gov (United States)

    Meier, Timothy B; Drevets, Wayne C; Wurfel, Brent E; Ford, Bart N; Morris, Harvey M; Victor, Teresa A; Bodurka, Jerzy; Teague, T Kent; Dantzer, Robert; Savitz, Jonathan

    2016-03-01

    Reductions in gray matter volume of the medial prefrontal cortex (mPFC), especially the rostral and subgenual anterior cingulate cortex (rACC, sgACC) are a widely reported finding in major depressive disorder (MDD). Inflammatory mediators, which are elevated in a subgroup of patients with MDD, activate the kynurenine metabolic pathway and increase production of neuroactive metabolites such as kynurenic acid (KynA), 3-hydroxykynurenine (3HK) and quinolinic acid (QA) which influence neuroplasticity. It is not known whether the alterations in brain structure and function observed in major depressive disorders are due to the direct effect of inflammatory mediators or the effects of neurotoxic kynurenine metabolites. Here, using partial posterior predictive distribution mediation analysis, we tested whether the serum concentrations of kynurenine pathway metabolites mediated reductions in cortical thickness in mPFC regions in MDD. Further, we tested whether any association between C-reactive protein (CRP) and cortical thickness would be mediated by kynurenine pathway metabolites. Seventy-three unmedicated subjects who met DSM-IV-TR criteria for MDD and 91 healthy controls (HC) completed MRI scanning using a pulse sequence optimized for tissue contrast resolution. Automated cortical parcellation was performed using the PALS-B12 Brodmann area atlas as implemented in FreeSurfer in order to compare the cortical thickness and cortical area of six PFC regions: Brodmann areas (BA) 9, 10, 11, 24, 25, and 32. Serum concentrations of kynurenine pathway metabolites were determined by high performance liquid chromatography (HPLC) with tandem mass spectrometry (MS/MS) detection, while high-sensitivity CRP concentration was measured immunoturbidimetrically. Compared with HCs, the MDD group showed a reduction in cortical thickness of the right BA24 (pdepressive episodes displayed thinner cortex in BA32 (pmediated the relationship between diagnosis and cortical thickness of right BA32

  3. A COMPARATIVE STUDY ON THE ACTIVITY OF ALANIN-AMINOTRANSFERASE IN HYPOPHTHALMICHTHYS MOLITRIX AND ARISTICHTHYS NOBILIS

    Directory of Open Access Journals (Sweden)

    Gabriela Vasile

    2006-08-01

    Full Text Available The present paper represents a comparative study on the activity of one aminotransferase - alaninaminotransferase, in the digestive tube of Hypophthalmichthys molitrix (silver carp and Aristichthys nobilis (bighead carp. The enzymatic activity has been determined colorimetrically, with 2, 4 - dinitrophenyl hydrazine, the results obtained being expressed as UE / g / min. It was observed that, comparatively with the alanin-aminotransferase activity recorded in silver carp, in the case of bighead carp, the values recorded are much lower.

  4. Kynurenine pathway metabolites are associated with hippocampal activity during autobiographical memory recall in patients with depression.

    Science.gov (United States)

    Young, Kymberly D; Drevets, Wayne C; Dantzer, Robert; Teague, T Kent; Bodurka, Jerzy; Savitz, Jonathan

    2016-08-01

    Inflammation-related changes in the concentrations of inflammatory mediators such as c-reactive protein (CRP), interleukin 1β (IL-1), and IL-6 as well as kynurenine metabolites are associated with major depressive disorder (MDD) and affect depressive behavior, cognition, and hippocampal plasticity in animal models. We previously reported that the ratios of kynurenic acid (KynA) to the neurotoxic metabolites, 3-hydroxykynurenine (3HK) and quinolinic acid (QA), were positively correlated with hippocampal volume in depression. The hippocampus is critical for autobiographical memory (AM) recall which is impaired in MDD. Here we tested whether the ratios, KynA/3HK and KynA/QA were associated with AM recall performance as well as hippocampal activity during AM recall. Thirty-five unmedicated depressed participants and 25 healthy controls (HCs) underwent fMRI scanning while recalling emotionally-valenced AMs and provided serum samples for the quantification of kynurenine metabolites, CRP, and cytokines (IL-1 receptor antagonist - IL-1RA; IL-6, tumor necrosis factor alpha - TNF, interferon gamma -IFN-γ, IL-10). KynA/3HK and KynA/QA were lower in the MDD group relative to the HCs. The concentrations of the CRP and the cytokines did not differ significantly between the HCs and the MDD group. Depressed individuals recalled fewer specific AMs and displayed increased left hippocampal activity during the recall of positive and negative memories. KynA/3HK was inversely associated with left hippocampal activity during specific AM recall in the MDD group. Further, KynA/QA was positively correlated with percent negative specific memories recalled in the MDD group and showed a non-significant trend toward a positive correlation with percent positive specific memories recalled in HCs. In contrast, neither CRP nor the cytokines were significantly associated with AM recall or activity of the hippocampus during AM recall. Conceivably, an imbalance in levels of KynA versus QA

  5. Cerebrospinal fluid kynurenine and kynurenic acid concentrations are associated with coma duration and long-term neurocognitive impairment in Ugandan children with cerebral malaria.

    Science.gov (United States)

    Holmberg, Dag; Franzén-Röhl, Elisabeth; Idro, Richard; Opoka, Robert O; Bangirana, Paul; Sellgren, Carl M; Wickström, Ronny; Färnert, Anna; Schwieler, Lilly; Engberg, Göran; John, Chandy C

    2017-07-28

    One-fourth of children with cerebral malaria (CM) retain cognitive sequelae up to 2 years after acute disease. The kynurenine pathway of the brain, forming neuroactive metabolites, e.g. the NMDA-receptor antagonist kynurenic acid (KYNA), has been implicated in long-term cognitive dysfunction in other CNS infections. In the present study, the association between the kynurenine pathway and neurologic/cognitive complications in children with CM was investigated. Cerebrospinal fluid (CSF) concentrations of KYNA and its precursor kynurenine in 69 Ugandan children admitted for CM to Mulago Hospital, Kampala, Uganda, between 2008 and 2013 were assessed. CSF kynurenine and KYNA were compared to CSF cytokine levels, acute and long-term neurologic complications, and long-term cognitive impairments. CSF kynurenine and KYNA from eight Swedish children without neurological or infectious disease admitted to Astrid Lindgren's Children's Hospital were quantified and used for comparison. Children with CM had significantly higher CSF concentration of kynurenine and KYNA than Swedish children (P coma duration in children of all ages (P = 0.003 and 0.04, respectively), and CSF kynurenine concentrations were associated with worse overall cognition (P = 0.056) and attention (P = 0.003) at 12-month follow-up in children ≥5 years old. CSF KYNA and kynurenine are elevated in children with CM, indicating an inhibition of glutamatergic and cholinergic signaling. This inhibition may lead acutely to prolonged coma and long-term to impairment of attention and cognition.

  6. Structural and mechanistic basis of differentiated inhibitors of the acute pancreatitis target kynurenine-3-monooxygenase

    Science.gov (United States)

    Hutchinson, Jonathan P.; Rowland, Paul; Taylor, Mark R. D.; Christodoulou, Erica M.; Haslam, Carl; Hobbs, Clare I.; Holmes, Duncan S.; Homes, Paul; Liddle, John; Mole, Damian J.; Uings, Iain; Walker, Ann L.; Webster, Scott P.; Mowat, Christopher G.; Chung, Chun-Wa

    2017-06-01

    Kynurenine-3-monooxygenase (KMO) is a key FAD-dependent enzyme of tryptophan metabolism. In animal models, KMO inhibition has shown benefit in neurodegenerative diseases such as Huntington's and Alzheimer's. Most recently it has been identified as a target for acute pancreatitis multiple organ dysfunction syndrome (AP-MODS); a devastating inflammatory condition with a mortality rate in excess of 20%. Here we report and dissect the molecular mechanism of action of three classes of KMO inhibitors with differentiated binding modes and kinetics. Two novel inhibitor classes trap the catalytic flavin in a previously unobserved tilting conformation. This correlates with picomolar affinities, increased residence times and an absence of the peroxide production seen with previous substrate site inhibitors. These structural and mechanistic insights culminated in GSK065(C1) and GSK366(C2), molecules suitable for preclinical evaluation. Moreover, revising the repertoire of flavin dynamics in this enzyme class offers exciting new opportunities for inhibitor design.

  7. Cognition and Emotions in Recurrent Depressive Disorders - The Role of Inflammation and the Kynurenine Pathway.

    Science.gov (United States)

    Talarowska, Monika; Galecki, Piotr

    2016-01-01

    Separating emotions from cognition seems impossible in everyday experiences of a human being. Emotional processes have an impact on the ability of planning and solving problems, or decision-making skills. They are a valuable source of information about ourselves, our partners in interactions and the surrounding world. Recent years have shown that axial symptoms of depression are caused by emotion regulation disorders, dysfunctions in the reward system and deficits of cognitive processes. There is a few studies concerning a link between emotional and inflammatory processes in depression. The aim of this article is to present results of contemporary research studies over mutual connections between social cognition, cognitive processes and inflammatory factors significant for the aetiology of recurrent depressive disorders, with particular reference to the role of kynurenine pathways.

  8. Peripheral kynurenine-3-monooxygenase deficiency as a potential risk factor for metabolic syndrome in schizophrenia patients.

    Science.gov (United States)

    Oxenkrug, Gregory; van der Hart, Marieke; Roeser, Julien; Summergrad, Paul

    2017-01-01

    Increased predisposition of schizophrenia patients (SP) to development of obesity and insulin resistance suggested common signaling pathway between metabolic syndrome (MetS) and schizophrenia. Deficiency of kynurenine-3-monooxygenase (KMO), enzyme catalyzing formation of 3-hydroxykynurenine (3-HK) from kynurenine (Kyn), a tryptophan (Trp) metabolite, might contribute to development of MetS as suggested by non-expression of KMO genes in human fat tissue and elevated serum concentrations of Kyn and its metabolites, kynurenic (KYNA) and anthranilic (ANA) acids, in diabetic patients and Zucker fatty rats (ZFR). Markers of KMO deficiency: decreased 3-HK and elevated Kyn, KYNA and ANA, were observed in brains and spinal fluids of SP, and in brains and serum of experimental animals with genetically- or pharmacologically-induced KMO deficiency. However, elevated concentrations of ANA and decreased 3-HK were reported in serum of SP without concurrent increase of Kyn and KYNA. Present study aimed to re-assess serum Kyn metabolites (HPLC-MS) in a sub-group of SP with elevated KYNA. We found increased Kyn concentrations (by 30%) and Kyn:Trp ratio (by 20%) in serum of SP with elevated KYNA concentrations (by 40%). Obtained results and our previous data suggest that peripheral KMO deficiency might be manifested by, at least, two different patterns: elevated ANA with decreased 3-HK; and elevated KYNA and KYN. The latter pattern was previously described in type 2 diabetes patients and might underline increased predisposition of SP to development of MetS. Assessment of peripheral KMO deficiency might identify SP predisposed to MetS. Attenuation of the consequences of peripheral KMO deficiency might be a new target for prevention/treatment of obesity and diabetes in SP.

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

    Directory of Open Access Journals (Sweden)

    Ross Grant

    2010-01-01

    Full Text Available Efficient synthesis of NAD + is critical to maintaining cell viability in all organs of the body. However, little is known of the pathway(s by which cells of the central nervous system produce NAD + . The aim of this study was to investigate the relationship, between tryptophan degradation via the kynurenine pathway (KP and de novo NAD + synthesis in human astrocytes, a major cell type within the brain. In this study we observed that inhibition of single enzymes of the KP resulted in significant decreases in NAD + levels in astroglial cells after a 24 hr period. We also observed that astrocytes cultured in media deficient in tryptophan, nicotinic acid and nicotinamide resulted in a 50% decrease in NAD + levels after 24 hrs. This decrease in NAD + was partially restored by supplementation of the culture media with either tryptophan or kynurenine, or nicotinic acid or with supply of the salvage pathway precursor nicotinamide.

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

    Science.gov (United States)

    Grant, Ross; Nguyen, Susan; Guillemin, Gilles

    2010-01-01

    Efficient synthesis of NAD+ is critical to maintaining cell viability in all organs of the body. However, little is known of the pathway(s) by which cells of the central nervous system produce NAD+. The aim of this study was to investigate the relationship, between tryptophan degradation via the kynurenine pathway (KP) and de novo NAD+ synthesis in human astrocytes, a major cell type within the brain. In this study we observed that inhibition of single enzymes of the KP resulted in significant decreases in NAD+ levels in astroglial cells after a 24 hr period. We also observed that astrocytes cultured in media deficient in tryptophan, nicotinic acid and nicotinamide resulted in a 50% decrease in NAD+ levels after 24 hrs. This decrease in NAD+ was partially restored by supplementation of the culture media with either tryptophan or kynurenine, or nicotinic acid or with supply of the salvage pathway precursor nicotinamide. PMID:22084595

  11. Dysbiosis of the Vaginal Microbiota and Higher Vaginal Kynurenine/Tryptophan Ratio Reveals an Association with Chlamydia trachomatis Genital Infections

    Directory of Open Access Journals (Sweden)

    Noa Ziklo

    2018-01-01

    Full Text Available The natural course of Chlamydia trachomatis urogenital tract infections varies between individuals. While protective immunity can occur, some women can become reinfected, contributing to the development of severe pathology. While the reasons for these differences are unknown, an individual's response to induced interferon-γ (IFN-γ is suggested to be critical. IFN-γ induction of the enzyme indoleamine 2,3-dioxygenase, which depletes tryptophan, may be the key. One hypothesis suggests that indole-producing bacteria in the vaginal microbiota can provide a substrate for the Chlamydia to synthesize tryptophan, rescuing the Chlamydia from host IFN-γ attack. We studied a cohort of 25 women who were either, Chlamydia negative, Chlamydia positive with a single infection, or Chlamydia positive with repeated infection, to test our hypothesis. We characterized their vaginal microbiota, cytokine response, as well as their tryptophan, kynurenine and indole concentrations directly in vaginal secretions. We found that C. trachomatis urogenital tract infections either initial or repeat infections, were associated with elevated vaginal kynurenine/tryptophan ratios, primarily as a result of elevated kynurenine levels. In addition, vaginal microbiota of community state type (CST IV showed significantly lower vaginal tryptophan levels compared to CST I and III, which might be related to a higher abundance of indole producers found within this group. Furthermore, we found a higher abundance of indole producers in women who cleared their Chlamydia infection post antibiotic treatment. This study demonstrates for the first time in vivo, the association between high vaginal kynurenine/tryptophan ratios and C. trachomatis infections. In addition, tryptophan depletion was associated with vaginal microbiota of CST IV.

  12. DYSFUNCTIONAL KYNURENINE PATHWAY METABOLISM IN THE R6/2 MOUSE MODEL OF HUNTINGTON’S DISEASE

    Science.gov (United States)

    Sathyasaikumar, Korrapati V.; Stachowski, Erin K.; Amori, Laura; Guidetti, Paolo; Muchowski, Paul J.; Schwarcz, Robert

    2013-01-01

    Elevated concentrations of neurotoxic metabolites of the kynurenine pathway (KP) of tryptophan degradation may play a causative role in Huntington’s disease (HD). The brain levels of one of these compounds, 3-hydroxykynurenine (3-HK), are increased in both HD and several mouse models of the disease. In the present study, we examined this impairment in greater detail using the R6/2 mouse, a well-established animal model of HD. Initially, mutant and age-matched wild-type mice received an intrastriatal injection of 3H-tryptophan to assess the acute, local de novo production of kynurenine, the immediate bioprecursor of 3-HK, in vivo. No effect of genotype was observed between 4 and 12 weeks of age. In contrast, intrastriatally applied 3H-kynurenine resulted in significantly increased neosynthesis of 3H-3-HK, but not other tritiated KP metabolites, in the R6/2 striatum. Subsequent ex vivo studies in striatal, cortical and cerebellar tissue revealed substantial increases in the activity of the biosynthetic enzyme of 3-HK, kynurenine 3-monooxygenase (KMO) and significant reductions in the activity of its degradative enzyme, kynureninase, in HD mice starting at 4 weeks of age. Decreased kynureninase activity was most evident in the cortex and preceded the increase in KMO activity. The activity of other KP enzymes showed no consistent brain abnormalities in the mutant mice. These findings suggest that impairments in its immediate metabolic enzymes jointly account for the abnormally high brain levels of 3-HK in the R6/2 model of HD. PMID:20236387

  13. Inhibition of the kynurenine pathway protects against reactive microglial-associated reductions in the complexity of primary cortical neurons.

    Science.gov (United States)

    O'Farrell, Katherine; Fagan, Eimear; Connor, Thomas J; Harkin, Andrew

    2017-09-05

    Brain glia possess the rate limiting enzyme indoleamine 2, 3-dioxygenase (IDO) which catalyses the conversion of tryptophan to kynurenine. Microglia also express kynurenine monooxygenase (KMO) and kynureninase (KYNU) which lead to the production of the free radical producing metabolites, 3-hydroxykynurenine and 3-hydroxyanthranillic acid respectively and subsequently production of the NMDA receptor agonist quinolinic acid. The aim of this study was to examine the effect of IFNγ-stimulated kynurenine pathway (KP) induction in microglia on neurite outgrowth and complexity, and to determine whether alterations could be abrogated using pharmacological inhibitors of the KP. BV-2 microglia were treated with IFNγ (5ng/ml) for 24h and conditioned media (CM) was placed on primary cortical neurons 3 days in vitro (DIV) for 48h. Neurons were fixed and neurite outgrowth and complexity was assessed using fluorescent immunocytochemistry followed by Sholl analysis. Results show increased mRNA expression of IDO, KMO and KYNU, and increased concentrations of tryptophan, kynurenine, and 3-hydroxykynurenine in the CM of IFNγ-stimulated BV-2 microglia. The IFNγ-stimulated BV-2 microglial CM reduced neurite outgrowth and complexity with reductions in various parameters of neurite outgrowth prevented when BV-2 microglia were pre-treated with either the IDO inhibitor, 1-methyltryptophan (1-MT) (L) (0.5mM; 30min), the KMO inhibitor, Ro 61-8048 (1μM; 30min), the synthetic glucocorticoid, dexamethasone (1μM; 2h) -which suppresses IFNγ-induced IDO - and the N-methyl-D-aspartate (NMDA) receptor antagonist, MK801 (0.1μM; 30min). Overall this study indicates that inhibition of the KP in microglia may be targeted to protect against reactive microglial-associated neuronal atrophy. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. New insight into the antidepressants action: modulation of kynurenine pathway by increasing the kynurenic acid/3-hydroxykynurenine ratio.

    Science.gov (United States)

    Kocki, Tomasz; Wnuk, Sebastian; Kloc, Renata; Kocki, Janusz; Owe-Larsson, Björn; Urbanska, Ewa M

    2012-02-01

    Altered function of kynurenine pathway has emerged recently as one of the factors contributing to the pathogenesis of depression. Neuroprotective kynurenic acid (KYNA) and neurotoxic 3-hydroxykynurenine (3-HK) are two immediate metabolites of L: -kynurenine. Here, we aimed to assess the hypothesis that antidepressant drugs that may change brain KYNA/3-HK ratio. In primary astroglial cultures, fluoxetine, citalopram, amitriptyline and imipramine (1-10 μM) increased de novo production of KYNA and diminished 3-HK synthesis (24 and 48, but not 2 h). RT-PCR studies revealed that Kat1, Kat2 and kynurenine-3-monooxygenase (Kmo) gene expressions were not altered after 2 h. At 24 h, the expression of Kat1 and Kat2 genes was enhanced by all studied drugs, whereas Kmo expression was diminished by citalopram, fluoxetine and amitriptyline, but not imipramine. After 48 h, the expression of Kat1 and Kat2 was further up-regulated, and Kmo expression was down-regulated by all antidepressants. The ratio KYNA/3-HK was increased by fluoxetine, citalopram, amitriptyline and imipramine in a time-dependent manner-the effect was not observed after 2 h, modest after 24 h and robust after 48 h incubation time. Our findings indicate that the action of antidepressants may involve re-establishing of the beneficial ratio between KYNA and 3-HK. Shift in the kynurenine pathway, observed after prolonged exposure to antidepressant drugs, may partly explain their delayed therapeutic effectiveness.

  15. Prenatal inhibition of the kynurenine pathway leads to structural changes in the hippocampus of adult rat offspring

    OpenAIRE

    Khalil, Omari S; Pisar, Mazura; Forrest, Caroline M; Vincenten, Maria C J; Darlington, L Gail; Stone, Trevor W

    2014-01-01

    Glutamate receptors for N-methyl-d-aspartate (NMDA) are involved in early brain development. The kynurenine pathway of tryptophan metabolism includes the NMDA receptor agonist quinolinic acid and the antagonist kynurenic acid. We now report that prenatal inhibition of the pathway in rats with 3,4-dimethoxy-N-[4-(3-nitrophenyl)thiazol-2-yl]benzenesulphonamide (Ro61-8048) produces marked changes in hippocampal neuron morphology, spine density and the immunocytochemical localisation of developme...

  16. Alanine aminotransferase, gamma-glutamyltransferase (GGT) and all-cause mortality: results from a population-based Danish twins study alanine aminotransferase, GGT and mortality in elderly twins

    DEFF Research Database (Denmark)

    Fraser, Abigail; Thinggaard, Mikael; Christensen, Kaare

    2009-01-01

    Abstract Background/Aims: Alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT) are widely used markers of liver disease. Several population-based cohort studies have found associations of these liver enzymes with all-cause mortality. None of these studies controlled for genetic...... for potential confounders and existing diabetes and cardiovascular disease. Environmental developmental origins may explain the association, but larger twin studies are required to replicate our findings....

  17. Smaller Dentate Gyrus and CA2 and CA3 Volumes Are Associated with Kynurenine Metabolites in Collegiate Football Athletes.

    Science.gov (United States)

    Meier, Timothy B; Savitz, Jonathan; Singh, Rashmi; Teague, T Kent; Bellgowan, Patrick S F

    2016-07-15

    An imbalance in kynurenine pathway metabolism is hypothesized to be associated with dysregulated glutamatergic neurotransmission, which has been proposed as a mechanism underlying the hippocampal volume loss observed in a variety of neurological disorders. Pre-clinical models suggest that the CA2-3 and dentate gyrus hippocampal subfields are particularly susceptible to excitotoxicity after experimental traumatic brain injury. We tested the hypothesis that smaller hippocampal volumes in collegiate football athletes with (n = 25) and without (n = 24) a concussion history would be most evident in the dentate gyrus and CA2-3 subfields relative to nonfootball healthy controls (n = 27). Further, we investigated whether the concentration of peripheral levels of kynurenine metabolites are altered in football athletes. Football athletes with and without a self-reported concussion history had smaller dentate gyrus (p Football athletes with and without a concussion history had a trend toward lower (p history had greater levels of quinolinic acid compared with athletes without a concussion history (p football athletes with a concussion history (p football athletes without a concussion history (p < 0.05). Our results raise the possibility that abnormalities of the kynurenine metabolic pathway constitute a mechanism for hippocampal volume differences in the context of sports-related brain injury.

  18. Overexpression of human kynurenine-3-monooxygenase protects against 3-hydroxykynurenine-mediated apoptosis through bidirectional nonlinear feedback.

    Science.gov (United States)

    Wilson, K; Auer, M; Binnie, M; Zheng, X; Pham, N T; Iredale, J P; Webster, S P; Mole, D J

    2016-04-14

    Kynurenine 3-monooxygenase (KMO) is a critical regulator of inflammation. The preferred KMO substrate, kynurenine, is converted to 3-hydroxykynurenine (3HK), and this product exhibits cytotoxicity through mechanisms that culminate in apoptosis. Here, we report that overexpression of human KMO with orthotopic localisation to mitochondria creates a metabolic environment during which the cell exhibits increased tolerance for exogenous 3HK-mediated cellular injury. Using the selective KMO inhibitor Ro61-8048, we show that KMO enzyme function is essential for cellular protection. Pan-caspase inhibition with Z-VAD-FMK confirmed apoptosis as the mode of cell death. By defining expression of pathway components upstream and downstream of KMO, we observed alterations in other key kynurenine pathway components, particularly tryptophan-2,3-dioxygenase upregulation, through bidirectional nonlinear feedback. KMO overexpression also increased expression of inducible nitric oxide synthase (iNOS). These changes in gene expression are functionally relevant, because siRNA knockdown of the pathway components kynureninase and quinolinate phosphoribosyl transferase caused cells to revert to a state of susceptibility to 3HK-mediated apoptosis. In summary, KMO overexpression, and importantly KMO activity, have metabolic repercussions that fundamentally affect resistance to cell stress.

  19. Alzheimer's disease evaluation using label-free, stainless, fluorescence to measure tryptophan metabolism along the kynurenine pathway

    Science.gov (United States)

    Sordillo, Laura A.; Zhang, Lin; Shi, Lingyan; Sriramoju, Vidyasagar; Sordillo, Peter P.; Alfano, Robert R.

    2018-02-01

    Under stress conditions, pro-inflammatory cytokines, such as tumor necrosis factor-alpha, interleukin-1 beta, interleukin 6 and interferon gamma are released. It is known that these cytokines stimulate indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO), which increase tryptophan metabolism through the kynurenine pathway, and that this can cause increased production of neurotoxic compounds. Brain tissues from Alzheimer's disease patients and agematched controls were investigated using label-free fluorescence spectroscopy. Tryptophan (exc. 280/ em. 340 nm) and its metabolites (N-formyl-L-kynurenine (exc. 325/em. 434 nm), kynurenine (exc. 365/em. 480 nm) and kynurenic acid (exc. 330/em. 390 nm)) have distinct spectral profiles. Preliminary results show a difference in the optical signatures in three important areas of the brain (hippocampus, BA 9, BA 17) between patients with Alzheimer's disease and agedmatched controls (normal), and a marked relative increase in tryptophan in the Alzheimer's patients. Thus determinations of tryptophan to tryptophan metabolite ratios could potentially be used to measure IDO and TDO activity and the degree of inflammation in the brain. This label-free optical technique may be useful in the study of Alzheimer's and other neurodegenerative diseases.

  20. Effects of Various Kynurenine Metabolites on Respiratory Parameters of Rat Brain, Liver and Heart Mitochondria

    Directory of Open Access Journals (Sweden)

    Halina Baran*

    2016-01-01

    Full Text Available Previously, we demonstrated that the endogenous glutamate receptor antagonist kynurenic acid dose-dependently and significantly affected rat heart mitochondria. Now we have investigated the effects of L-tryptophan, L-kynurenine, 3-hydroxykynurenine and kynurenic, anthranilic, 3-hydroxyanthranilic, xanthurenic and quinolinic acids on respiratory parameters (ie, state 2, state 3, respiratory control index (RC and ADP/oxygen ratio in brain, liver and heart mitochondria of adult rats. Mitochondria were incubated with glutamate/malate (5 mM or succinate (10 mM and in the presence of L-tryptophan metabolites (1 mM or in the absence, as control. Kynurenic and anthranilic acids significantly reduced RC values of heart mitochondria in the presence of glutamate/malate. Xanthurenic acid significantly reduced RC values of brain mitochondria in the presence of glutamate/malate. Furthermore, 3-hydroxykynurenine and 3-hydroxyanthranilic acid decreased RC values of brain, liver and heart mitochondria using glutamate/malate. In the presence of succinate, 3-hydroxykynurenine and 3-hydroxyanthranilic acid affected RC values of brain mitochondria, whereas in liver and heart mitochondria only 3-hydroxykynurenine lowered RC values significantly. Furthermore, lowered ADP/oxygen ratios were observed in brain mitochondria in the presence of succinate with 3-hydroxykynurenine and 3-hydroxyanthranilic acid, and to a lesser extent with glutamate/malate. In addition, 3-hydroxyanthranilic acid significantly lowered the ADP/oxygen ratio in heart mitochondria exposed to glutamate/malate, while in the liver mitochondria only a mild reduction was found. Tests of the influence of L-tryptophan and its metabolites on complex I in liver mitochondria showed that only 3-hydroxykynurenine, 3-hydroxyanthranilic acid and L-kynurenine led to a significant acceleration of NADH-driven complex I activities. The data indicate that L-tryptophan metabolites had different effects on brain, liver

  1. Liver alanine aminotransferase, insulin resistance and endothelial dysfunction in normotriglyceridaemic subjects with type 2 diabetes mellitus

    NARCIS (Netherlands)

    Schindhelm, RK; Diamant, M; Bakker, SJL; van Dijk, RAJM; Scheffer, PG; Teerlink, T; Kostense, PJ; Heine, RJ

    Background Plasma levels of liver transaminases, including alanine aminotransferase (ALT), are elevated in most cases of nonalcoholic fatty liver disease (NAFLD). Elevated ALT levels are associated with insulin resistance, and subjects with NAFLD have features of the metabolic syndrome that confer

  2. Alanine aminotransferase and mortality in patients with type 2 diabetes (ZODIAC-38)

    NARCIS (Netherlands)

    Deetman, Petronella E.; Alkhalaf, Alaa; Landman, Gijs W. D.; Groenier, Klaas H.; Kootstra-Ros, Jenny E.; Navis, Gerjan; Bilo, Henk J. G.; Kleefstra, Nanne; Bakker, Stephan J. L.

    Introduction Combined data suggest a bimodal association of alanine aminotransferase (ALT) with mortality in the general population. Little is known about the association of ALT with mortality in patients with type 2 diabetes. We therefore investigated the association of ALT with all-cause,

  3. Liver alanine aminotransferase, insulin resistance and endothelial dysfunction in normotriglyceridaemic subjects with type 2 diabetes mellitus

    NARCIS (Netherlands)

    Schindhelm, R.K.; Diamant, M.; Bakker, S.J.L.; van Dijk, R.A.; Scheffer, P.G.; Teerlink, T.; Kostense, P.J.; Heine, R.J.

    2005-01-01

    Background: Plasma levels of liver transaminases, including alanine aminotransferase (ALT), are elevated in most cases of nonalcoholic fatty liver disease (NAFLD). Elevated ALT levels are associated with insulin resistance, and subjects with NAFLD have features of the metabolic syndrome that confer

  4. Identification and Partial Characterization of an L-Tyrosine Aminotransferase (TAT from Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Pranav R. Prabhu

    2010-01-01

    Full Text Available The aminotransferase gene family in the model plant Arabidopsis thaliana consists of 44 genes. Twenty six of these enzymes are classified as characterized meaning that the reaction(s that the enzyme catalyzes are documented using experimental means. The remaining 18 enzymes are uncharacterized and are therefore deemed putative. Our laboratory is interested in elucidating the function(s of the remaining putative aminotransferase enzymes. To this end, we have identified and partially characterized an aminotransferase (TAT enzyme from Arabidopsis annotated by the locus tag At5g36160. The full-length cDNA was cloned and the purified recombinant enzyme was characterized using in vitro and in vivo experiments. In vitro analysis showed that the enzyme is capable of interconverting L-Tyrosine and 4-hydroxyphenylpyruvate, and L-Phenylalanine and phenylpyruvate. In vivo analysis by functional complementation showed that the gene was able to complement an E. coli with a background of aminotransferase mutations that confers auxotrophy for L-Tyrosine and L-Phenylalanine.

  5. Structural studies of Pseudomonas and Chromobacterium ω-aminotransferases provide insights into their differing substrate specificity

    International Nuclear Information System (INIS)

    Sayer, Christopher; Isupov, Michail N.; Westlake, Aaron; Littlechild, Jennifer A.

    2013-01-01

    The X-ray structures of two ω-aminotransferases from P. aeruginosa and C. violaceum in complex with an inhibitor offer the first detailed insight into the structural basis of the substrate specificity of these industrially important enzymes. The crystal structures and inhibitor complexes of two industrially important ω-aminotransferase enzymes from Pseudomonas aeruginosa and Chromobacterium violaceum have been determined in order to understand the differences in their substrate specificity. The two enzymes share 30% sequence identity and use the same amino acceptor, pyruvate; however, the Pseudomonas enzyme shows activity towards the amino donor β-alanine, whilst the Chromobacterium enzyme does not. Both enzymes show activity towards S-α-methylbenzylamine (MBA), with the Chromobacterium enzyme having a broader substrate range. The crystal structure of the P. aeruginosa enzyme has been solved in the holo form and with the inhibitor gabaculine bound. The C. violaceum enzyme has been solved in the apo and holo forms and with gabaculine bound. The structures of the holo forms of both enzymes are quite similar. There is little conformational difference observed between the inhibitor complex and the holoenzyme for the P. aeruginosa aminotransferase. In comparison, the crystal structure of the C. violaceum gabaculine complex shows significant structural rearrangements from the structures of both the apo and holo forms of the enzyme. It appears that the different rigidity of the protein scaffold contributes to the substrate specificity observed for the two ω-aminotransferases

  6. Transient Elastography vs. Aspartate Aminotransferase to Platelet Ratio Index in Hepatitis C: A Meta-Analysis.

    Science.gov (United States)

    Mattos, A Z; Mattos, A A

    Many different non-invasive methods have been studied with the purpose of staging liver fibrosis. The objective of this study was verifying if transient elastography is superior to aspartate aminotransferase to platelet ratio index for staging fibrosis in patients with chronic hepatitis C. A systematic review with meta-analysis of studies which evaluated both non-invasive tests and used biopsy as the reference standard was performed. A random-effects model was used, anticipating heterogeneity among studies. Diagnostic odds ratio was the main effect measure, and summary receiver operating characteristic curves were created. A sensitivity analysis was planned, in which the meta-analysis would be repeated excluding each study at a time. Eight studies were included in the meta-analysis. Regarding the prediction of significant fibrosis, transient elastography and aspartate aminotransferase to platelet ratio index had diagnostic odds ratios of 11.70 (95% confidence interval = 7.13-19.21) and 8.56 (95% confidence interval = 4.90-14.94) respectively. Concerning the prediction of cirrhosis, transient elastography and aspartate aminotransferase to platelet ratio index had diagnostic odds ratios of 66.49 (95% confidence interval = 23.71-186.48) and 7.47 (95% confidence interval = 4.88-11.43) respectively. In conclusion, there was no evidence of significant superiority of transient elastography over aspartate aminotransferase to platelet ratio index regarding the prediction of significant fibrosis, but the former proved to be better than the latter concerning prediction of cirrhosis.

  7. Apoenzyme of aspartate aminotransferase isozymes in serum and its diagnostic usefullness for hepatic diseases.

    Science.gov (United States)

    Kamei, S; Ohkubo, A; Yamanaka, M

    1979-08-15

    Aspartate aminotransferase in the sera of normal subjects and of patients with hepatic diseases has been immunologically separated into two isoenzymes, cytosolic aspartate aminotransferase and mitochondrial aspartate aminotransferase. The activity of the isoenzymes was measured in three different buffer solutions with or without pyridoxal 5'-phosphate. To attain maximal activation, the apoenzyme of mitochondrial fraction must be preincubated with pyridoxal 5'-phosphate longer than that of the cytosolic fraction in either of the three reaction mixtures. In most sera the activity of both isoenzymes increased substantially in the presence of pyridoxal 5'-phosphate regardless of the type of buffer solutions. Both the apoenzymatic activity and the ratio of apo- to holo-enzymatic activity of each of the isoenzymes varied among samples from the patients with hepatic diseases. However, significantly high ratios of apo- to holo-enzymatic activity of both isoenzymes were observed in the patients with hepatoma in contrast with those with other hepatic diseases. These findings suggest that the simultaneous measurement of both apo- and holo-enzyme activities of aspartate aminotransferase isoenzymes may be useful in the clinical assessment of hepatic diseases.

  8. Identification of (R)-selective ω-aminotransferases by exploring evolutionary sequence space.

    Science.gov (United States)

    Kim, Eun-Mi; Park, Joon Ho; Kim, Byung-Gee; Seo, Joo-Hyun

    2018-03-01

    Several (R)-selective ω-aminotransferases (R-ωATs) have been reported. The existence of additional R-ωATs having different sequence characteristics from previous ones is highly expected. In addition, it is generally accepted that R-ωATs are variants of aminotransferase group III. Based on these backgrounds, sequences in RefSeq database were scored using family profiles of branched-chain amino acid aminotransferase (BCAT) and d-alanine aminotransferase (DAT) to predict and identify putative R-ωATs. Sequences with two profile analysis scores were plotted on two-dimensional score space. Candidates with relatively similar scores in both BCAT and DAT profiles (i.e., profile analysis score using BCAT profile was similar to profile analysis score using DAT profile) were selected. Experimental results for selected candidates showed that putative R-ωATs from Saccharopolyspora erythraea (R-ωAT_Sery), Bacillus cellulosilyticus (R-ωAT_Bcel), and Bacillus thuringiensis (R-ωAT_Bthu) had R-ωAT activity. Additional experiments revealed that R-ωAT_Sery also possessed DAT activity while R-ωAT_Bcel and R-ωAT_Bthu had BCAT activity. Selecting putative R-ωATs from regions with similar profile analysis scores identified potential R-ωATs. Therefore, R-ωATs could be efficiently identified by using simple family profile analysis and exploring evolutionary sequence space. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. PPARα regulates the hepatotoxic biomarker alanine aminotransferase (ALT1) gene expression in human hepatocytes

    International Nuclear Information System (INIS)

    Thulin, Petra; Rafter, Ingalill; Stockling, Kenneth; Tomkiewicz, Celine; Norjavaara, Ensio; Aggerbeck, Martine; Hellmold, Heike; Ehrenborg, Ewa; Andersson, Ulf; Cotgreave, Ian; Glinghammar, Bjoern

    2008-01-01

    In this work, we investigated a potential mechanism behind the observation of increased aminotransferase levels in a phase I clinical trial using a lipid-lowering drug, the peroxisome proliferator-activated receptor (PPAR) α agonist, AZD4619. In healthy volunteers treated with AZD4619, serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were elevated without an increase in other markers for liver injury. These increases in serum aminotransferases have previously been reported in some patients receiving another PPARα agonist, fenofibrate. In subsequent in vitro studies, we observed increased expression of ALT1 protein and mRNA in human hepatocytes after treatment with fenofibric acid. The PPAR effect on ALT1 expression was shown to act through a direct transcriptional mechanism involving at least one PPAR response element (PPRE) in the proximal ALT1 promoter, while no effect of fenofibrate and AZD4619 was observed on the ALT2 promoter. Binding of PPARs to the PPRE located at - 574 bp from the transcriptional start site was confirmed on both synthetic oligonucleotides and DNA in hepatocytes. These data show that intracellular ALT expression is regulated by PPAR agonists and that this mechanism might contribute to increased ALT activity in serum

  10. Beta-alanine/alpha-ketoglutarate aminotransferase for 3-hydroxypropionic acid production

    Science.gov (United States)

    Jessen, Holly Jean [Chanhassen, MN; Liao, Hans H [Eden Prairie, MN; Gort, Steven John [Apple Valley, MN; Selifonova, Olga V [Plymouth, MN

    2011-10-04

    The present disclosure provides novel beta-alanine/alpha ketoglutarate aminotransferase nucleic acid and protein sequences having increased biological activity. Also provided are cells containing such enzymes, as well as methods of their use, for example to produce malonyl semialdehyde and downstream products thereof, such as 3-hydroxypropionic acid and derivatives thereof.

  11. Characterization of the different spectral forms of glutamate 1-semialdehyde aminotransferase by mass spectrometry

    DEFF Research Database (Denmark)

    Brody, S; Andersen, Jens S.; Kannangara, C G

    1995-01-01

    Glutamate 1-semialdehyde aminotransferase produces delta-aminolevulinate for the synthesis of chlorophyll, heme, and other tetrapyrrole pigments. The native enzyme from Synechococcus is pale yellow and has absorption maxima at 338 and 418 nm from vitamin B6. Yellow, colorless, and pink forms...

  12. Associated factors and clinical implications of serum aminotransferase elevation in scrub typhus.

    Science.gov (United States)

    Su, Tung-Hung; Liu, Chun-Jen; Shu, Pei-Yun; Fu, Yang-Hsien; Chang, Chi-Hsien; Jao, Ping; Kao, Jia-Horng

    2016-12-01

    Timely diagnosis and prompt treatment can reduce the complications of scrub typhus. It is thus important to find easy laboratory tests to help in the diagnosis, especially in patients without eschar at initial presentation. Because serum aminotransferase elevation is common in scrub typhus, its associated factors and clinical implications need further investigations. We conducted a retrospective study in Kinmen, Taiwan, to collect clinically suspected scrub typhus patients notified to Taiwan Centers for Disease Control for confirmation during 2005-2010. Scrub typhus was diagnosed and Orientia tsutsugamushi was genotyped by serological or molecular assays. The laboratory data and clinical information were recorded for analysis. Overall, 344 suspected scrub typhus patients were reported to Taiwan Centers for Disease Control and 288 of them were certified scrub typhus. Scrub typhus patients had significantly more thrombocytopenia, serum aminotransferase elevation (76% vs. 54%, p = 0.001), higher frequency of fever, eschar, and lymphadenopathy, compared with nontyphus patients. Hepatic dysfunction in scrub typhus was associated with older age, longer fever duration, and absence of lymphadenopathy, but seemed to be unrelated to the rickettsial genotypes. Multivariate analysis showed that serum aminotransferase elevation (odds ratio: 3.75; p = 0.003; 95% confidence interval: 1.56-9.01) independently predicted scrub typhus. Furthermore, in suspected scrub typhus patients without eschar, 92% of true typhus patients had serum aminotransferase elevation compared with the nontyphus ones (odds ratio: 6.47; p = 0.028, 95% confidence interval: 1.23-34.11). Hepatic dysfunction in scrub typhus patients is associated with older age, longer fever duration, and absence of lymphadenopathy. Serum aminotransferase elevation can aid in the diagnosis of scrub typhus, especially in suspected patients without eschar. Copyright © 2014. Published by Elsevier B.V.

  13. The Effects of Extra Virgin Olive Oil on Alanine Aminotransferase, Aspartate Aminotransferase, and Ultrasonographic Indices of Hepatic Steatosis in Nonalcoholic Fatty Liver Disease Patients Undergoing Low Calorie Diet

    Directory of Open Access Journals (Sweden)

    Farzad Shidfar

    2018-01-01

    Full Text Available Background. Coronary artery disease is the most common cause of death in the patients with nonalcoholic fatty liver disease (NAFLD. Studies have shown that there is a strong relation between the increase in the aminotransferase levels and fat accumulation in the liver with cardiovascular complications, independent of all aspects of the metabolic syndrome. This study aimed to examine the effect of virgin olive oil on alanine aminotransferase (ALT and aspartate aminotransferase (AST and the severity of steatosis in the NAFLD patients undergoing a weight-loss diet. Methods. This clinical trial was carried out on 50 patients with nonalcoholic fatty liver (mean age of 45.91 ± 9.61 years, mean BMI of 29.7 ± 0.58 Kg/m2 and the subjects were randomly assigned to the olive oil group (receiving the equivalent of 20% of their total daily energy requirement from olive oil or the control group (with normal consumption of oil for 12 weeks. All the patients received a hypocaloric diet during the study. At the beginning and the end of the study, the serum levels of ALT and AST and liver steatosis were measured. Findings. A significant decrease in the level of ALT enzymes was observed in the control group at the end of the study (P = 0.004. In the olive oil group, both enzymes decreased compared to baseline measurements (P<0.01. There were significant differences in the ALT and AST levels between the two groups (P<0.02. The severity of liver steatosis did not change significantly during the study. Conclusion. The consumption of a low calorie diet enriched with olive oil, along with slight weight reduction, reinforces the desired effects of weight loss in improving the levels of the hepatic enzymes.

  14. The Effects of Extra Virgin Olive Oil on Alanine Aminotransferase, Aspartate Aminotransferase, and Ultrasonographic Indices of Hepatic Steatosis in Nonalcoholic Fatty Liver Disease Patients Undergoing Low Calorie Diet.

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    Shidfar, Farzad; Bahrololumi, Samaneh Sadat; Doaei, Saeid; Mohammadzadeh, Assieh; Gholamalizadeh, Maryam; Mohammadimanesh, Ali

    2018-01-01

    Coronary artery disease is the most common cause of death in the patients with nonalcoholic fatty liver disease (NAFLD). Studies have shown that there is a strong relation between the increase in the aminotransferase levels and fat accumulation in the liver with cardiovascular complications, independent of all aspects of the metabolic syndrome. This study aimed to examine the effect of virgin olive oil on alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and the severity of steatosis in the NAFLD patients undergoing a weight-loss diet. This clinical trial was carried out on 50 patients with nonalcoholic fatty liver (mean age of 45.91 ± 9.61 years, mean BMI of 29.7 ± 0.58 Kg/m 2 ) and the subjects were randomly assigned to the olive oil group (receiving the equivalent of 20% of their total daily energy requirement from olive oil) or the control group (with normal consumption of oil) for 12 weeks. All the patients received a hypocaloric diet during the study. At the beginning and the end of the study, the serum levels of ALT and AST and liver steatosis were measured. A significant decrease in the level of ALT enzymes was observed in the control group at the end of the study ( P = 0.004). In the olive oil group, both enzymes decreased compared to baseline measurements ( P groups ( P < 0.02). The severity of liver steatosis did not change significantly during the study. The consumption of a low calorie diet enriched with olive oil, along with slight weight reduction, reinforces the desired effects of weight loss in improving the levels of the hepatic enzymes.

  15. Structural Basis for Inhibitor-Induced Hydrogen Peroxide Production by Kynurenine 3-Monooxygenase.

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    Kim, Hyun Tae; Na, Byeong Kwan; Chung, Jiwoung; Kim, Sulhee; Kwon, Sool Ki; Cha, Hyunju; Son, Jonghyeon; Cho, Joong Myung; Hwang, Kwang Yeon

    2018-04-19

    Kynurenine 3-monooxygenase (KMO) inhibitors have been developed for the treatment of neurodegenerative disorders. The mechanisms of flavin reduction and hydrogen peroxide production by KMO inhibitors are unknown. Herein, we report the structure of human KMO and crystal structures of Saccharomyces cerevisiae (sc) and Pseudomonas fluorescens (pf) KMO with Ro 61-8048. Proton transfer in the hydrogen bond network triggers flavin reduction in p-hydroxybenzoate hydroxylase, but the mechanism triggering flavin reduction in KMO is different. Conformational changes via π-π interactions between the loop above the flavin and substrate or non-substrate effectors lead to disorder of the C-terminal α helix in scKMO and shifts of domain III in pfKMO, stimulating flavin reduction. Interestingly, Ro 61-8048 has two different binding modes. It acts as a competitive inhibitor in scKMO and as a non-substrate effector in pfKMO. These findings provide understanding of the catalytic cycle of KMO and insight for structure-based drug design of KMO inhibitors. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. A magnetic bead-based ligand binding assay to facilitate human kynurenine 3-monooxygenase drug discovery.

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    Wilson, Kris; Mole, Damian J; Homer, Natalie Z M; Iredale, John P; Auer, Manfred; Webster, Scott P

    2015-02-01

    Human kynurenine 3-monooxygenase (KMO) is emerging as an important drug target enzyme in a number of inflammatory and neurodegenerative disease states. Recombinant protein production of KMO, and therefore discovery of KMO ligands, is challenging due to a large membrane targeting domain at the C-terminus of the enzyme that causes stability, solubility, and purification difficulties. The purpose of our investigation was to develop a suitable screening method for targeting human KMO and other similarly challenging drug targets. Here, we report the development of a magnetic bead-based binding assay using mass spectrometry detection for human KMO protein. The assay incorporates isolation of FLAG-tagged KMO enzyme on protein A magnetic beads. The protein-bound beads are incubated with potential binding compounds before specific cleavage of the protein-compound complexes from the beads. Mass spectrometry analysis is used to identify the compounds that demonstrate specific binding affinity for the target protein. The technique was validated using known inhibitors of KMO. This assay is a robust alternative to traditional ligand-binding assays for challenging protein targets, and it overcomes specific difficulties associated with isolating human KMO. © 2014 Society for Laboratory Automation and Screening.

  17. The Kynurenine Pathway As a Novel Link between Allergy and the Gut Microbiome

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    Aaron P. Van der Leek

    2017-11-01

    Full Text Available In the past few decades, the indoleamine 2,3 dioxygenase (IDO subset of the kynurenine (KYN pathway of tryptophan (TRP metabolism has been the subject of much research in the area of immune tolerance. In this review, we aim to incorporate new findings on this pathway in relation to allergy and the gut microbiome, while providing a comprehensive overview of the pathway itself. Stimulated by interferon gamma, IDO acts as a tolerogenic, immunosuppressive enzyme to attenuate allergic responses by the induction of the KYN-IDO pathway, resultant depletion of TRP, and elevation in KYN metabolites. Acting through the aryl hydrocarbon receptor, KYN metabolites cause T-cell anergy and apoptosis, proliferation of Treg and Th17 cells, and deviation of the Th1/Th2 response, although the outcome is highly dependent on the microenvironment. Moreover, new evidence from germ-free mice and human infants shows that gut microbiota and breast milk are key in determining the functioning of the KYN-IDO pathway. As such, we recommend further research on how this pathway may be a critical link between the microbiome and development of allergy.

  18. Clinical value of spleen acoustic radiation force impulse, aspartate aminotransferase-to-platelet ratio index, and aspartate aminotransferase/alanine aminotransferase ratio in predicting esophageal varices in patients with liver cirrhosis

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    ZHANG Dakun

    2018-03-01

    Full Text Available ObjectiveTo investigate the spleen stiffness of patients with chronic hepatitis and liver cirrhosis by spleen acoustic radiation force impulse (ARFI, aspartate aminotransferase-to-platelet ratio index (APRI, and aspartate aminotransferase/alanine aminotransferase ratio (AAR, as well as the clinical value of these three noninvasive techniques in predicting esophageal varices (EV in patients with liver cirrhosis. MethodsA total of 247 patients with chronic hepatitis and liver cirrhosis were enrolled, and ARFI was used to measure real-time spleen stiffness. APRI and AAR were calculated. Gastroscopy was performed within one week before and after measurement to clarify the degree of EV. With the results of gastroscopy as the gold standard, the receiver operating characteristic (ROC curve was used to compare the clinical value of spleen ARFI value, APRI, and AAR in the diagnosis of EV in patients with liver cirrhosis. The t-test was used for comparison of continuous data between two groups. ResultsThere were significant differences between the EV group (n=169 and the non-EV group (n=78 in spleen ARFI stiffness (3.64±0.53 m/s vs 2.97±0.65 m/s, t=-7.93, P<0.001, APRI (0.87±091 vs 0.52±0.80, t=-2.90, P=0.004, and AAR (1.54±0.67 vs 1.29±0.55, t=-2.93, P=0.004. Spleen ARFI, APRI, and AAR had an area under the ROC curve of 0.80, 0.72, and 0.63, respectively, in predicting EV in patients with liver cirrhosis, there was a significant difference between spleen ARFI stiffness and AAR (P=0.005, while there was no significant difference between spleen ARFI stiffness and APRI (P=0.10. ConclusionARFI is a real-time ultrasound elastography technique, and compared with APRI and AAR, spleen stiffness measured by ARFI can predict EV in patients with chronic hepatitis and liver cirrhosis more accurately and noninvasively and thus holds promise for clinical application.

  19. Association of the Aspartate Aminotransferase to Alanine Aminotransferase Ratio with BNP Level and Cardiovascular Mortality in the General Population: The Yamagata Study 10-Year Follow-Up

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    Miyuki Yokoyama

    2016-01-01

    Full Text Available Background. Early identification of high risk subjects for cardiovascular disease in health check-up is still unmet medical need. Cardiovascular disease is characterized by the superior increase in aspartate aminotransferase (AST to alanine aminotransferase (ALT. However, the association of AST/ALT ratio with brain natriuretic peptide (BNP levels and cardiovascular mortality remains unclear in the general population. Methods and Results. This longitudinal cohort study included 3,494 Japanese subjects who participated in a community-based health check-up, with a 10-year follow-up. The AST/ALT ratio increased with increasing BNP levels. And multivariate logistic analysis showed that the AST/ALT ratio was significantly associated with a high BNP (≥100 pg/mL. There were 250 all-cause deaths including 79 cardiovascular deaths. Multivariate Cox proportional hazard regression analysis revealed that a high AST/ALT ratio (>90 percentile was an independent predictor of all-cause and cardiovascular mortality after adjustment for confounding factors. Kaplan-Meier analysis demonstrated that cardiovascular mortality was higher in subjects with a high AST/ALT ratio than in those without. Conclusions. The AST/ALT ratio was associated with an increase in BNP and was predictive of cardiovascular mortality in a general population. Measuring the AST/ALT ratio during routine health check-ups may be a simple and cost-effective marker for cardiovascular mortality.

  20. Downregulated kynurenine 3-monooxygenase gene expression and enzyme activity in schizophrenia and genetic association with schizophrenia endophenotypes.

    Science.gov (United States)

    Wonodi, Ikwunga; Stine, O Colin; Sathyasaikumar, Korrapati V; Roberts, Rosalinda C; Mitchell, Braxton D; Hong, L Elliot; Kajii, Yasushi; Thaker, Gunvant K; Schwarcz, Robert

    2011-07-01

    Kynurenic acid, a metabolite of the kynurenine pathway of tryptophan degradation, is an antagonist at N-methyl-d-aspartate and α7 nicotinic acetylcholine receptors and modulates glutamate, dopamine, and acetylcholine signaling. Cortical kynurenic acid concentrations are elevated in the brain and cerebrospinal fluid of schizophrenia patients. The proximal cause may be an impairment of kynurenine 3-monooxygenase (KMO), a rate-limiting enzyme at the branching point of the kynurenine pathway. To examine KMO messenger RNA expression and KMO enzyme activity in postmortem tissue from the frontal eye field (FEF; Brodmann area 6) obtained from schizophrenia individuals compared with healthy control individuals and to explore the relationship between KMO single-nucleotide polymorphisms and schizophrenia oculomotor endophenotypes. Case-control postmortem and clinical study. Maryland Brain Collection, outpatient clinics. Postmortem specimens from schizophrenia patients (n = 32) and control donors (n = 32) and a clinical sample of schizophrenia patients (n = 248) and healthy controls (n = 228). Comparison of quantitative KMO messenger RNA expression and KMO enzyme activity in postmortem FEF tissue between schizophrenia patients and controls and association of KMO single-nucleotide polymorphisms with messenger RNA expression in postmortem FEF and schizophrenia and oculomotor endophenotypes (ie, smooth pursuit eye movements and oculomotor delayed response). In postmortem tissue, we found a significant and correlated reduction in KMO gene expression and KMO enzyme activity in the FEF in schizophrenia patients. In the clinical sample, KMO rs2275163 was not associated with a diagnosis of schizophrenia but showed modest effects on predictive pursuit and visuospatial working memory endophenotypes. Our results provide converging lines of evidence implicating reduced KMO activity in the etiopathophysiology of schizophrenia and related neurocognitive deficits.

  1. Genetic variants of the kynurenine-3-monooxygenase and postpartum depressive symptoms after cesarean section in Chinese women.

    Science.gov (United States)

    Wang, Sai-Ying; Duan, Kai-Ming; Tan, Xiao-Fang; Yin, Ji-Ye; Mao, Xiao-Yuan; Zheng, Wei; Wang, Chun-Yan; Yang, Mi; Peng, Cheng; Zhou, Hong-Hao; Liu, Zhao-Qian

    2017-06-01

    New conceptualizations of depression have emphasized the role of the kynurenine pathway (KP) in the pathogenesis of postpartum depressive symptoms (PDS). Kynurenine 3-monooxygenase (KMO) is a rate-limiting enzyme of the KP, where it catalyzes the conversion of kynurenine (KYN) to 3-hydroxykynurenine (3-HK). Previous work indicates that KMO is closely linked to the pathophysiology of depressive disorders. The purpose of this study is to investigate whether variations in the KMO gene affect PDS development after cesarean section. A total of 710 Chinese women receiving cesarean section were enrolled in this study. PDS was determined by an Edinburgh Postnatal Depression Scale (EPDS) score ≥13. Subsequently, 24 women with PDS and 48 matched women without PDS were randomly selected for investigation of perinatal serum concentrations of KYN, 3-HK and the 3-HK/KYN ratio. The 3-HK/KYN ratio indicates the activity of KMO. In addition, 6 single nucleotide polymorphisms of the KMO gene were examined. Following this genotyping, 36 puerperant women carrying the KMO rs1053230 AG genotype and 72 matched puerperant women carrying the KMO rs1053230 GG genotype were selected for comparisons of KYN, 3-HK and 3-HK/KYN ratio levels. The results show the incidence of PDS in the Chinese population to be 7.3%, with PDS characterized by increased serum 3-HK concentration and 3-HK/KYN ratio, versus matched postpartum women without PDS (PKMO rs1053230 are significantly associated with the incidence of PDS (PKMO rs1053230 AG genotype are significantly higher than those in matched postpartum women carrying the KMO rs1053230 GG genotype. The presented data highlight the contribution of alterations in the KP to the pathogenesis of postpartum depression. Heightened KMO activity, including as arising from KMO rs1053230 G/A genetic variations, are indicated as one possible mechanism driving the biological underpinnings of PDS. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Development of a Series of Kynurenine 3-Monooxygenase Inhibitors Leading to a Clinical Candidate for the Treatment of Acute Pancreatitis.

    Science.gov (United States)

    Walker, Ann L; Ancellin, Nicolas; Beaufils, Benjamin; Bergeal, Marylise; Binnie, Margaret; Bouillot, Anne; Clapham, David; Denis, Alexis; Haslam, Carl P; Holmes, Duncan S; Hutchinson, Jonathan P; Liddle, John; McBride, Andrew; Mirguet, Olivier; Mowat, Christopher G; Rowland, Paul; Tiberghien, Nathalie; Trottet, Lionel; Uings, Iain; Webster, Scott P; Zheng, Xiaozhong; Mole, Damian J

    2017-04-27

    Recently, we reported a novel role for KMO in the pathogenesis of acute pancreatitis (AP). A number of inhibitors of kynurenine 3-monooxygenase (KMO) have previously been described as potential treatments for neurodegenerative conditions and particularly for Huntington's disease. However, the inhibitors reported to date have insufficient aqueous solubility relative to their cellular potency to be compatible with the intravenous (iv) dosing route required in AP. We have identified and optimized a novel series of high affinity KMO inhibitors with favorable physicochemical properties. The leading example is exquisitely selective, has low clearance in two species, prevents lung and kidney damage in a rat model of acute pancreatitis, and is progressing into preclinical development.

  3. Molecular and phenotypic characterization of transgenic wheat and sorghum events expressing the barley alanine aminotransferase.

    Science.gov (United States)

    Peña, Pamela A; Quach, Truyen; Sato, Shirley; Ge, Zhengxiang; Nersesian, Natalya; Dweikat, Ismail M; Soundararajan, Madhavan; Clemente, Tom

    2017-12-01

    The expression of a barley alanine aminotransferase gene impacts agronomic outcomes in a C3 crop, wheat. The use of nitrogen-based fertilizers has become one of the major agronomic inputs in crop production systems. Strategies to enhance nitrogen assimilation and flux in planta are being pursued through the introduction of novel genetic alleles. Here an Agrobacterium-mediated approach was employed to introduce the alanine aminotransferase from barley (Hordeum vulgare), HvAlaAT, into wheat (Triticum aestivum) and sorghum (Sorghum bicolor), regulated by either constitutive or root preferred promoter elements. Plants harboring the transgenic HvAlaAT alleles displayed increased alanine aminotransferase (alt) activity. The enhanced alt activity impacted height, tillering and significantly boosted vegetative biomass relative to controls in wheat evaluated under hydroponic conditions, where the phenotypic outcome across these parameters varied relative to time of year study was conducted. Constitutive expression of HvAlaAT translated to elevation in wheat grain yield under field conditions. In sorghum, expression of HvAlaAT enhanced enzymatic activity, but no changes in phenotypic outcomes were observed. Taken together these results suggest that positive agronomic outcomes can be achieved through enhanced alt activity in a C3 crop, wheat. However, the variability observed across experiments under greenhouse conditions implies the phenotypic outcomes imparted by the HvAlaAT allele in wheat may be impacted by environment.

  4. Analysis of the enzymatic properties of a broad family of alanine aminotransferases.

    Directory of Open Access Journals (Sweden)

    Chandra H McAllister

    Full Text Available Alanine aminotransferase (AlaAT has been studied in a variety of organisms due to the involvement of this enzyme in mammalian processes such as non-alcoholic hepatocellular damage, and in plant processes such as C4 photosynthesis, post-hypoxic stress response and nitrogen use efficiency. To date, very few studies have made direct comparisons of AlaAT enzymes and fewer still have made direct comparisons of this enzyme across a broad spectrum of organisms. In this study we present a direct kinetic comparison of glutamate:pyruvate aminotransferase (GPAT activity for seven AlaATs and two glutamate:glyoxylate aminotransferases (GGAT, measuring the K(M values for the enzymes analyzed. We also demonstrate that recombinant expression of AlaAT enzymes in Eschericia coli results in differences in bacterial growth inhibition, supporting previous reports of AlaAT possessing bactericidal properties, attributed to lipopolysaccharide endotoxin recognition and binding. A probable lipopolysaccharide binding region within the AlaAT enzymes, homologous to a region of a lipopolysaccharide binding protein (LBP in humans, was also identified in this study. The AlaAT enzyme differences identified here indicate that AlaAT homologues have differentiated significantly and the roles these homologues play in vivo may also have diverged significantly. Specifically, the differing kinetics of AlaAT enzymes and how this may alter the nitrogen use efficiency in plants is discussed.

  5. Hepatic aminotransferases of normal and IUGR fetuses in cord blood at birth.

    Science.gov (United States)

    Kocylowski, Rafal; Dubiel, Mariusz; Gudmundsson, Saemundur; Fritzer, Elfriede; Kiserud, Torvid; von Kaisenberg, Constantin

    2012-07-01

    The accepted standard for assessing the wellbeing of the newborn is the Apgar score and blood gas analysis. However, the prediction of neonatal morbidity or mortality is limited. In small-for-gestation (SGA) fetuses at 18-38 weeks of gestation, pO(2) is normals. To test the hypothesis, that fetuses with intra uterine growth restriction (IUGR) have elevated AST (GOT) and ALT (GPT) aminotransferases as a result of hypoxic liver cell injury, and to establish references ranges. Prospective cohort study, serum of umbilical artery (n=156) and vein (n=180), 599 normal singletons at 37(+0)-42(+0)weeks, neonates with IUGR (n=41), analysis for pH, birthweight and maternal weight, spontaneous vs cesarean section, vein vs artery and for the sex. Aspartate aminotransferase (AST, GOT) and Alanine aminotransferase (ALT, GPT) were measured in normals and IUGR neonates. Neonates with IUGR (n=41) had AST values that were not different from the reference group, but had significantly lower ALT (-1.49, 95% CI -1.98 to -1.00 vs 0.14, 95% CI -0.42-0.13), (pblood were not elevated. Rather, a substantially reduced ALT suggests a down-regulated hepatic activity. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Protein Homeostasis Defects of Alanine-Glyoxylate Aminotransferase: New Therapeutic Strategies in Primary Hyperoxaluria Type I

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    Angel L. Pey

    2013-01-01

    Full Text Available Alanine-glyoxylate aminotransferase catalyzes the transamination between L-alanine and glyoxylate to produce pyruvate and glycine using pyridoxal 5′-phosphate (PLP as cofactor. Human alanine-glyoxylate aminotransferase is a peroxisomal enzyme expressed in the hepatocytes, the main site of glyoxylate detoxification. Its deficit causes primary hyperoxaluria type I, a rare but severe inborn error of metabolism. Single amino acid changes are the main type of mutation causing this disease, and considerable effort has been dedicated to the understanding of the molecular consequences of such missense mutations. In this review, we summarize the role of protein homeostasis in the basic mechanisms of primary hyperoxaluria. Intrinsic physicochemical properties of polypeptide chains such as thermodynamic stability, folding, unfolding, and misfolding rates as well as the interaction of different folding states with protein homeostasis networks are essential to understand this disease. The view presented has important implications for the development of new therapeutic strategies based on targeting specific elements of alanine-glyoxylate aminotransferase homeostasis.

  7. Assessment of the Human Kynurenine Pathway: Comparisons and Clinical Implications of Ethnic and Gender Differences in Plasma Tryptophan, Kynurenine Metabolites, and Enzyme Expressions at Baseline and after Acute Tryptophan Loading and Depletion

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    Abdulla A.-B. Badawy

    2016-01-01

    Full Text Available Tryptophan (Trp metabolism via the kynurenine pathway (KP was assessed in normal healthy US volunteers at baseline and after acute Trp depletion (ATD and acute Trp loading (ATL using amino acid formulations. The hepatic KP accounts for ~90% of overall Trp degradation. Liver Trp 2,3-dioxygenase (TDO contributes ~70% toward Trp oxidation, with the remainder achieved by subsequent rate-limiting enzymes in the KP. TDO is not influenced by a 1.15 g Trp load, but is maximally activated by a 5.15 g dose. We recommend a 30 mg/kg dose for future ATL studies. ATD activates TDO and enhances the Trp flux down the KP via its leucine component. Higher plasma free [Trp] and lower total [Trp] are observed in women, with no gender differences in kynurenines. Kynurenic acid is lower in female Caucasians, which may explain their lower incidence of schizophrenia. African-American and Hispanic women have a lower TDO and Trp oxidation relative to free Trp than the corresponding men. African-American women have a potentially higher 3-hydroxyanthranilic acid/anthranilic acid ratio, which may protect them against osteoporosis. Future studies of the KP in relation to health and disease should focus on gender and ethnic differences.

  8. Prognostic value of pretreatment serum alanine aminotransferase/aspartate aminotransferase (ALT/AST) ratio and gamma glutamyltransferase (GGT) in patients with esophageal squamous cell carcinoma.

    Science.gov (United States)

    Huang, Hao; Wang, Xue-Ping; Li, Xiao-Hui; Chen, Hao; Zheng, Xin; Lin, Jian-Hua; Kang, Ting; Zhang, Lin; Chen, Pei-Song

    2017-08-14

    The levels of liver function tests (LFTs) are often used to assess liver injury and non-liver disease-related mortality. In our study, the relationship between pretreatment serum LFTs and overall survival (OS) was evaluated in esophageal squamous cell carcinoma (ESCC) patients. Our purpose was to investigate the prognostic value of the preoperative alanine aminotransferase/aspartate aminotransferase (ALT/AST) ratio and gamma glutamyltransferase (GGT) in ESCC patients. A retrospective study was performed in 447 patients with ESCC, and follow-up period was at least 60 months until death. The prognostic significance of serum LFTs were determined by univariate and multivariate Cox hazard models. LFTs including ALT, AST, LSR, GGT, TBA and LDH were analyzed. Serum LSR (HR: 0.592, 95% CI = 0.457-0.768, p < 0.001 and GGT (HR: 1.507, 95% CI = 1.163-1.953, p = 0.002) levels were indicated as significant predictors of OS. The 5-year OS among patients with higher LSR levels was longer compared with those patients with decreased LSR levels, not only in the whole cohort but also in the subgroups stratified by pathological stage (T1-T2 subgroup, T3-T4 subgroup, N0 subgroup and M0 subgroup). We also found that patients with a higher GGT might predict worse OS than patients with a normal GGT, not only in the whole cohort but also in the subgroups stratified by pathological stage (T3-T4 subgroup and N1-N2 subgroup). Both increased levels of LSR and decreased levels of GGT might predict shorter overall survival in ESCC patients. Our findings suggest that serum LSR and GGT levels could be used as a key predictor of survival in patients with ESCC.

  9. Kynurenine 3-monooxygenase mediates inhibition of Th17 differentiation via catabolism of endogenous aryl hydrocarbon receptor ligands.

    Science.gov (United States)

    Stephens, Geoffrey L; Wang, Qun; Swerdlow, Bonnie; Bhat, Geetha; Kolbeck, Roland; Fung, Michael

    2013-07-01

    The aryl hydrocarbon receptor (AhR) is a key transcriptional regulator of Th17-cell differentiation. Although endogenous ligands have yet to be identified, evidence suggests that tryptophan metabolites can act as agonists for the AhR. Tryptophan metabolites are abundant in circulation, so we hypothesized that cell intrinsic factors might exist to regulate the exposure of Th17 cells to AhR-dependent activities. Here, we find that Th17 cells preferentially express kynurenine 3-monooxygenase (KMO), which is an enzyme involved in catabolism of the tryptophan metabolite kynurenine. KMO inhibition, either with a specific inhibitor or via siRNA-mediated silencing, markedly increased IL-17 production in vitro, whereas IFN-γ production by Th1 cells was unaffected. Inhibition of KMO significantly exacerbated disease in a Th17-driven model of autoimmune gastritis, suggesting that expression of KMO by Th17 cells serves to limit their continuous exposure to physiological levels of endogenous AhR ligands in vivo. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Prognostic significance of kynurenine 3-monooxygenase and effects on proliferation, migration, and invasion of human hepatocellular carcinoma.

    Science.gov (United States)

    Jin, Haojie; Zhang, Yurong; You, Haiyan; Tao, Xuemei; Wang, Cun; Jin, Guangzhi; Wang, Ning; Ruan, Haoyu; Gu, Dishui; Huo, Xisong; Cong, Wenming; Qin, Wenxin

    2015-06-23

    Kynurenine 3-monooxygenase (KMO) is a pivotal enzyme in the kynurenine pathway of tryptophan degradation and plays a critical role in Huntington's and Alzheimer's diseases. This study aimed to examine the expression of KMO in human hepatocellular carcinoma (HCC) and investigate the relationship between its expression and prognosis of HCC patients. We first analyzed KMO expression in 120 paired HCC samples (HCC tissues vs matched adjacent non-cancerous liver tissues), and 205 clinical HCC specimens using immunohistochemistry (IHC). Kaplan-Meier survival and Cox regression analyses were executed to evaluate the prognosis of HCC. The results of IHC analysis showed that KMO expression was significantly higher in HCC tissues than that in normal liver tissues (all p KMO was an independent prognostic factor for overall survival (OS) and time to recurrence (TTR) (both pKMO positively regulated proliferation, migration, and invasion of HCC cells. These results suggest that KMO exhibits tumor-promoting effects towards HCC and it may serve as a novel prognostic marker in HCC.

  11. Increased Tregs associated with elevated Indoleamine-2,3-dioxygenase activity and an imbalanced Kynurenine pathway in IFNpositive primary Sjögren's syndrome

    NARCIS (Netherlands)

    N.I. Maria (Naomi); C.G. van Helden-Meeuwsen; Z. Brkić (Zana); S.M.J. Paulissen (Sandra); E.C. Steenwijk (Eline); V.A.S.H. Dalm (Virgil); P.L.A. van Daele (Paul); M.P. van Hagen (Martin); F.G.M. Kroese (Frans G.); J.A.G. van Roon (J. A G); A. Harkin (Andrew); A.W. Dik (Willem); H.A. Drexhage (Hemmo); E.W. Lubberts (Erik); M.A. Versnel (Marjan)

    2016-01-01

    textabstractIntroduction Indoleamine-2,3-dioxygenase (IDO), the rate-limiting enzyme converting tryptophan (TRP) to kynurenine (KYN), is driven in part by type I/II IFNs. Naïve T cells are polarized into FoxP3+ regulatory T cells (Tregs) upon exposure to either IDO+ cells or KYN. Recent studies

  12. Sarcopenia is a risk factor for elevated aminotransferase in men independently of body mass index, dietary habits, and physical activity.

    Science.gov (United States)

    Yoo, Ki Deok; Jun, Dae Won; Lee, Kang Nyeong; Lee, Hang Lak; Lee, Oh Young; Yoon, Byung Chul; Choi, Ho Soon

    2015-04-01

    Aminotransferase activity is a surrogate marker of liver injury showing strong correlations with obesity and metabolic syndrome. However, elevated aminotransferase activity is not uncommon in non-obese and non-alcoholic patients in clinical practice. To examine the relationship between sarcopenia and aminotransferase activity in a large population-based cohort. Data from the Korean National Health and Nutrition Examinations were used. A total of 13,431 subjects were included. A whole-body dual X-ray absorptiometry scan was performed on each patient to measure total and regional muscle mass. Appendicular skeletal muscle mass indices were also obtained. The prevalence of sarcopenia was significantly higher in the group with elevated aminotransferase levels than in the normal liver enzyme group (males: 26.5% vs. 16.9%; females: 38.3% vs. 22.1%, plevels. The frequency of elevated aminotransferase increased in male patients with sarcopenia after adjusting for potential confounding factors including age, body mass index, fasting glucose level, dietary, and exercise habits. However, the correlation was no longer observed in women after adjusting for body mass index. Sarcopenia is a risk factor for elevated aminotransferase in men, independently of body mass index, dietary habits, and physical activity. Copyright © 2015 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  13. The Interactions Between Kynurenine, Folate, Methionine and Pteridine Pathways in Obesity.

    Science.gov (United States)

    Engin, Ayse Basak; Engin, Atilla

    2017-01-01

    Obesity activates both innate and adaptive immune responses in adipose tissue. Elevated levels of eosinophils with depression of monocyte and neutrophil indicate the deficiencies in the immune system of morbidly obese individuals. Actually, adipose tissue macrophages are functional antigen-presenting cells that promote the proliferation of interferon-gamma (IFN-gamma)-producing CD4+ T cells in adipose tissue of obese subjects. Eventually, diet-induced obesity is associated with the loss of tissue homeostasis and development of type 1 inflammatory responses in visceral adipose tissue. Activity of inducible indoleamine 2,3-dioxygenase-1 (IDO-1) plays a major role under pro-inflammatory, IFN-gamma dominated settings. One of the two rate-limiting enzymes which can metabolize tryptophan to kynurenine is IDO-1. Tumor necrosis factor-alpha (TNF-alpha) correlates with IDO-1 in adipose compartments. Actually, IDO-1-mediated tryptophan catabolism due to chronic immune activation is the cause of reduced tryptophan plasma levels and be considered as the driving force for food intake in morbidly obese patients. Thus, decrease in plasma tryptophan levels and subsequent reduction in serotonin (5-HT) production provokes satiety dysregulation that leads to increased caloric uptake and obesity. However, after bariatric surgery, weight reduction does not lead to normalization of IDO-1 activity. Furthermore, there is a connection between arginine and tryptophan metabolic pathways in the generation of reactive nitrogen intermediates. Hence, abdominal obesity is associated with vascular endothelial dysfunction and reduced nitric oxide (NO) availability. IFN-gamma-induced activation of the inducible nitric oxide synthase (iNOS) and dissociation of endothelial adenosine monophosphate activated protein kinase (AMPK)- phosphoinositide 3-kinase (PI3K)-protein kinase B (Akt)- endothelial NO synthase (eNOS) pathway enhances oxidative stress production secondary to high-fat diet. Thus, reduced

  14. The Relationships among Tryptophan, Kynurenine, Indoleamine 2,3-Dioxygenase, Depression, and Neuropsychological Performance.

    Science.gov (United States)

    Hestad, Knut A; Engedal, Knut; Whist, Jon E; Farup, Per G

    2017-01-01

    It has been suggested that the metabolic enzyme indoleamine 2,3-dioxygenase (IDO) is a biological mediator of inflammation related to the psychopathology of depression, with a Kynurenine (KYN) increase in the Tryptophan (TRP) metabolic pathway, resulting in reduced Serotonin. In this study, we examined KYN, TRP, and the ratio of KYN to TRP concentrations × 10 3 (KT Ratio) in serum and cerebrospinal fluid (CSF) in (a) a group of depressed patients and (b) a control group of patients referred to a neurologic outpatient clinic for whom no specific diagnosis could be established. The KT Ratio is considered an index that represents IDO. The participants were examined with the Beck Depression Inventory II (BDI-II), the Montgomery Aasberg Depression Rating Scale (MADRS), and a neuropsychological test battery. We found no significant differences between the two study groups with respect to TRP, KYN, or KT Ratio in serum or CSF. Differences in neuropsychological performance between the two patient groups could be seen in the following tests: Animal Fluency, Digit Symbol, the DKEFS Color-Interference Test (Naming Part), Trail Making Test A and B, and the Grooved Pegboard Non-dominant Hand. KYN in serum correlated highly with KYN in CSF. KYN in serum correlated significantly with both age and gender. When analyzing males and females separately, we found that women had a lower level of TRP in both serum (Mann-Whitney U -test: TRP in Serum; p = 0.001) and CSF (Mann-Whitney U -test: TRP in CSF; p = 0.003). Women had a lower level of KYN in serum ( p = 0.029) than men did. Age was positively associated with KYN. KYN in CSF correlated only with age, however; there were no gender differences. No significant relationship was seen between BDI-II and MADRS on the one hand, and KYN and TRP on the other. KYN in CSF as the KT Ratio in both serum and CSF was associated with neuropsychological performance. Thus, we suggest that KYN and KT Ratio are related more strongly to

  15. The Relationships among Tryptophan, Kynurenine, Indoleamine 2,3-Dioxygenase, Depression, and Neuropsychological Performance

    Directory of Open Access Journals (Sweden)

    Knut A. Hestad

    2017-10-01

    Full Text Available It has been suggested that the metabolic enzyme indoleamine 2,3-dioxygenase (IDO is a biological mediator of inflammation related to the psychopathology of depression, with a Kynurenine (KYN increase in the Tryptophan (TRP metabolic pathway, resulting in reduced Serotonin. In this study, we examined KYN, TRP, and the ratio of KYN to TRP concentrations × 103 (KT Ratio in serum and cerebrospinal fluid (CSF in (a a group of depressed patients and (b a control group of patients referred to a neurologic outpatient clinic for whom no specific diagnosis could be established. The KT Ratio is considered an index that represents IDO. The participants were examined with the Beck Depression Inventory II (BDI-II, the Montgomery Aasberg Depression Rating Scale (MADRS, and a neuropsychological test battery. We found no significant differences between the two study groups with respect to TRP, KYN, or KT Ratio in serum or CSF. Differences in neuropsychological performance between the two patient groups could be seen in the following tests: Animal Fluency, Digit Symbol, the DKEFS Color-Interference Test (Naming Part, Trail Making Test A and B, and the Grooved Pegboard Non-dominant Hand. KYN in serum correlated highly with KYN in CSF. KYN in serum correlated significantly with both age and gender. When analyzing males and females separately, we found that women had a lower level of TRP in both serum (Mann–Whitney U-test: TRP in Serum; p = 0.001 and CSF (Mann–Whitney U-test: TRP in CSF; p = 0.003. Women had a lower level of KYN in serum (p = 0.029 than men did. Age was positively associated with KYN. KYN in CSF correlated only with age, however; there were no gender differences. No significant relationship was seen between BDI-II and MADRS on the one hand, and KYN and TRP on the other. KYN in CSF as the KT Ratio in both serum and CSF was associated with neuropsychological performance. Thus, we suggest that KYN and KT Ratio are related more strongly to

  16. Clinical relevance and discriminatory value of elevated liver aminotransferase levels for dengue severity.

    Science.gov (United States)

    Lee, Linda K; Gan, Victor C; Lee, Vernon J; Tan, Adriana S; Leo, Yee Sin; Lye, David C

    2012-01-01

    Elevation of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) is prominent in acute dengue illness. The World Health Organization (WHO) 2009 dengue guidelines defined AST or ALT ≥ 1000 units/liter (U/L) as a criterion for severe dengue. We aimed to assess the clinical relevance and discriminatory value of AST or ALT for dengue hemorrhagic fever (DHF) and severe dengue. We retrospectively studied and classified polymerase chain reaction positive dengue patients from 2006 to 2008 treated at Tan Tock Seng Hospital, Singapore according to WHO 1997 and 2009 criteria for dengue severity. Of 690 dengue patients, 31% had DHF and 24% severe dengue. Elevated AST and ALT occurred in 86% and 46%, respectively. Seven had AST or ALT ≥ 1000 U/L. None had acute liver failure but one patient died. Median AST and ALT values were significantly higher with increasing dengue severity by both WHO 1997 and 2009 criteria. However, they were poorly discriminatory between non-severe and severe dengue (e.g., AST area under the receiver operating characteristic [ROC] curve=0.62; 95% confidence interval [CI]: 0.57-0.67) and between dengue fever (DF) and DHF (AST area under the ROC curve=0.56; 95% CI: 0.52-0.61). There was significant overlap in AST and ALT values among patients with dengue with or without warning signs and severe dengue, and between those with DF and DHF. Although aminotransferase levels increased in conjunction with dengue severity, AST or ALT values did not discriminate between DF and DHF or non-severe and severe dengue.

  17. Impact of increasing alanine aminotransferase levels within normal range on incident diabetes

    OpenAIRE

    Chong-Shan Wang; Ting-Tsung Chang; Wei-Jen Yao; Shan-Tair Wang; Pesus Chou

    2012-01-01

    Abnormal alanine aminotransferase level (ALT) levels might be associated with type 2 diabetes, but whether higher ALT levels within the normal range predict the risk is unknown. Methods: We followed a community-based cohort of 3446 individuals who were ≥35 years old without diabetes and hepatitis B or C in southern Taiwan for 8 years (1997–2004) to study the risk for type 2 diabetes with different normal ALT levels. Results: Among the 337 incident diabetes cases, 16.0% were from those w...

  18. Inhibition study of alanine aminotransferase enzyme using sequential online capillary electrophoresis analysis.

    Science.gov (United States)

    Liu, Lina; Chen, Yuanfang; Yang, Li

    2014-12-15

    We report the study of several inhibitors on alanine aminotransferase (ALT) enzyme using sequential online capillary electrophoresis (CE) assay. Using metal ions (Na(+) and Mg(2+)) as example inhibitors, we show that evolution of the ALT inhibition reaction can be achieved by automatically and simultaneously monitoring the substrate consumption and product formation as a function of reaction time. The inhibition mechanism and kinetic constants of ALT inhibition with succinic acid and two traditional Chinese medicines were derived from the sequential online CE assay. Our study could provide valuable information about the inhibition reactions of ALT enzyme. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Common reference intervals for aspartate aminotransferase (AST), alanine aminotransferase (ALT) and γ-glutamyl transferase (GGT) in serum: results from an IFCC multicenter study.

    Science.gov (United States)

    Ceriotti, Ferruccio; Henny, Joseph; Queraltó, Josep; Ziyu, Shen; Özarda, Yeşim; Chen, Baorong; Boyd, James C; Panteghini, Mauro

    2010-11-01

    Aspartate aminotransferase (AST), alanine aminotransferase (ALT) and γ-glutamyl transferase (GGT) measurements are important for the assessment of liver damage. The aim of this study was to define the reference intervals (RIs) for these enzymes in adults, paying attention to standardization of the methods used and careful selection of the reference population. AST, ALT and GGT were measured with commercial analytical systems standardized to the IFCC-recommended reference measurement systems. Three centers (two in Italy and one in China) measured their own freshly collected samples; one of these centers also measured frozen samples from the Nordic Countries RI Project and from a Turkish center. RIs were generated using non-parametric techniques from the results of 765 individuals (411 females and 354 males, 18-85 years old) selected on the basis of the results of other laboratory tests and a specific questionnaire. AST results from the four regions (Milan, Beijing, Bursa and Nordic Countries) were statistically different, but these differences were too small to be clinically relevant. Likewise, differences between the upper reference limits for genders was only 1.7 U/L (0.03 μkat/L), allowing a single RI of 11-34 U/L (0.18-0.57 μkat/L) to be defined. Interregional differences were not statistically significant for ALT, but partitioning was required due to significant gender differences. RIs for ALT were 8-41 U/L (0.13-0.68 μkat/L) for females and 9-59 U/L (0.15-0.99 μkat/L) for males, respectively. The upper reference limits for GGT from the Nordic Country population were higher than those from the other three regions and results from this group were excluded from final calculations. The GGT RIs were 6-40 U/L (0.11-0.66 μkat/L) for females and 12-68 U/L (0.20- 1.13 μkat/L) for males, respectively. For AST and ALT, the implementation of common RIs appears to be possible, because no differences between regions were observed. However, a common RI for GGT that is

  20. Regulation of the kynurenine metabolism pathway by Xiaoyao San and the underlying effect in the hippocampus of the depressed rat.

    Science.gov (United States)

    Wang, Jiajia; Li, Xiaofang; He, Shugui; Hu, Lijun; Guo, Jiewen; Huang, Xiangning; Hu, Jinqing; Qi, Yaoqun; Chen, Bin; Shang, Dewei; Wen, Yuguan

    2018-03-25

    Xiaoyao San (XYS) is a classic Chinese herbal formula for treatment of depression. The present study aimed to investigate the antidepressant effects of XYS in a rat model of chronic unpredictable mild stress (CUMS) and the underlying mechanisms. A CUMS rat model of depression was established via 4 weeks of unpredictable stimulation. Then the rats were orally administered paroxetine and XYS for 2 weeks with continued stress. Behavioral assessments, including an open field test (OFT), sucrose preference test (SPT) and forced swim test (FST), were conducted to evaluate the antidepressant effects of XYS. The concentrations in rat plasma of tryptophan (Trp) and its metabolic products, including kynurenine (Kyn) and quinolinic acid (QUIN), were determined using high performance liquid chromatography tandem mass spectrometry with electrochemical detection (HPLC-MS/MS). The mRNA and protein levels in rat hippocampus of depression-related brain derived neurotrophic factor (BDNF), cyclic AMP response element binding protein (CREB) and nerve cell adhesion molecule (NCAM) were determined by real-time qPCR and Western blot, respectively. Enzyme Linked Immunosorbent Assay (ELISA) was used to detect the activities of indoleamine 2,3-dioxygenase (IDO) and kynurenine-3-monooxygenase (KMO) in rat plasma. The results showed that a successful CUMS rat model was established through 4 weeks of continuous unpredictable stimulation, as indicated by the significant decrease in locomotor activity and increase in immobility time in the OFT, reduction in body weight and food intake etc. Compared with the normal group, the concentrations of Kyn and QUIN had significantly (p KMO. Compared with the normal group, the mRNA of NCAM, CREB and BDNF were significantly down-regulated (p < 0.001) in the control group, BDNF gene was up-regulated by paroxetine or XYS treatment, NCAM and CREB gene did not change in XYS group, protein expressions of BDNF and CREB were significantly increased, and NCAM was

  1. An LL-diaminopimelate aminotransferase defines a novel variant of the lysine biosynthesis pathway in plants.

    Science.gov (United States)

    Hudson, André O; Singh, Bijay K; Leustek, Thomas; Gilvarg, Charles

    2006-01-01

    Although lysine (Lys) biosynthesis in plants is known to occur by way of a pathway that utilizes diaminopimelic acid (DAP) as a central intermediate, the available evidence suggests that none of the known DAP-pathway variants found in nature occur in plants. A new Lys biosynthesis pathway has been identified in Arabidopsis (Arabidopsis thaliana) that utilizes a novel transaminase that specifically catalyzes the interconversion of tetrahydrodipicolinate and LL-diaminopimelate, a reaction requiring three enzymes in the DAP-pathway variant found in Escherichia coli. The LL-DAP aminotransferase encoded by locus At4g33680 was able to complement the dapD and dapE mutants of E. coli. This result, in conjunction with the kinetic properties and substrate specificity of the enzyme, indicated that LL-DAP aminotransferase functions in the Lys biosynthetic direction under in vivo conditions. Orthologs of At4g33680 were identified in all the cyanobacterial species whose genomes have been sequenced. The Synechocystis sp. ortholog encoded by locus sll0480 showed the same functional properties as At4g33680. These results demonstrate that the Lys biosynthesis pathway in plants and cyanobacteria is distinct from the pathways that have so far been defined in microorganisms.

  2. Elevated Aminotransferase Activity as an Indication of Muscular Dystrophy: Case Reports and Review of the Literature

    Directory of Open Access Journals (Sweden)

    S Zamora

    1996-01-01

    Full Text Available Five male children are reported in whom incidental recognition of elevated serum alanine aminotransferase (ALT activity initiated investigation to identify the cause of suspected hepatocellular injury. All five were later diagnosed with X chromosome-linked muscular dystrophy. The serum level of ALT, generally considered to be specific for hepatocellular injury, was increased two to 25 times above normal in all the reported cases. Paradoxically, the increase in ALT activity was greater than that of serum aspartate aminotransferase (three to 16 times normal, an enzyme whose elevation is generally recognized as being less specific and indicative of muscle, cardiac, kidney, pancreatic, red blood cell or hepatic injury. At presentation to the gastrointestinal service, one case, age 2.5 months, had no symptoms or signs of neuromuscular dysfunction, while the other four had previously unrecognized hypertrophy of the calves, proximal limb weakness, positive Gower’s sign or delayed gross motor skills. All five patients had marked elevation of serum creatine kinase activity and histopathologically confirmed muscular dystrophy. The practical clinical implication of this report is that children with elevated serum ALT, in the absence of other signs and symptoms of hepatic injury, may have occult muscular disease - most frequently muscular dystrophy. Although the clinical signs of muscular dystrophy may be subtle or absent, early determination of creatine kinase will suggest the correct diagnosis and minimize extensive and invasive investigation focusing on hepatic injury.

  3. Development of a Rapid Fluorescence-Based High-Throughput Screening Assay to Identify Novel Kynurenine 3-Monooxygenase Inhibitor Scaffolds.

    Science.gov (United States)

    Jacobs, K R; Guillemin, G J; Lovejoy, D B

    2018-02-01

    Kynurenine 3-monooxygenase (KMO) is a well-validated therapeutic target for the treatment of neurodegenerative diseases, including Alzheimer's disease (AD) and Huntington's disease (HD). This work reports a facile fluorescence-based KMO assay optimized for high-throughput screening (HTS) that achieves a throughput approximately 20-fold higher than the fastest KMO assay currently reported. The screen was run with excellent performance (average Z' value of 0.80) from 110,000 compounds across 341 plates and exceeded all statistical parameters used to describe a robust HTS assay. A subset of molecules was selected for validation by ultra-high-performance liquid chromatography, resulting in the confirmation of a novel hit with an IC 50 comparable to that of the well-described KMO inhibitor Ro-61-8048. A medicinal chemistry program is currently underway to further develop our novel KMO inhibitor scaffolds.

  4. Upregulation of neuronal kynurenine 3-monooxygenase mediates depression-like behavior in a mouse model of neuropathic pain.

    Science.gov (United States)

    Laumet, Geoffroy; Zhou, Wenjun; Dantzer, Robert; Edralin, Jules D; Huo, XiaoJiao; Budac, David P; O'Connor, Jason C; Lee, Anna W; Heijnen, Cobi J; Kavelaars, Annemieke

    2017-11-01

    Pain and depression often co-occur, but the underlying mechanisms have not been elucidated. Here, we used the spared nerve injury (SNI) model in mice to induce both neuropathic pain and depression-like behavior. We investigated whether brain interleukin (IL)-1 signaling and activity of kynurenine 3-monoxygenase (KMO), a key enzyme for metabolism of kynurenine into the neurotoxic NMDA receptor agonist quinolinic acid, are necessary for comorbid neuropathic pain and depression-like behavior. SNI mice showed increased expression levels of Il1b and Kmo mRNA in the contralateral side of the brain. The SNI-induced increase of Kmo mRNA was associated with increased KMO protein and elevated quinolinic acid and reduced kynurenic acid in the contralateral hippocampus. The increase in KMO-protein in response to SNI mostly took place in hippocampal NeuN-positive neurons rather than microglia. Inhibition of brain IL-1 signaling by intracerebroventricular administration of IL-1 receptor antagonist after SNI prevented the increase in Kmo mRNA and depression-like behavior measured by forced swim test. However, inhibition of brain IL-1 signaling has no effect on mechanical allodynia. In addition, intracerebroventricular administration of the KMO inhibitor Ro 61-8048 abrogated depression-like behavior without affecting mechanical allodynia after SNI. We show for the first time that the development of depression-like behavior in the SNI model requires brain IL-1 signaling and activation of neuronal KMO, while pain is independent of this pathway. Inhibition of KMO may represent a promising target for treating depression. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Mass spectrometric measurement of urinary kynurenine-to-tryptophan ratio in children with and without urinary tract infection.

    Science.gov (United States)

    Yarbrough, Melanie L; Briden, Kelleigh E; Mitsios, John V; Weindel, Annette L; Terrill, Cindy M; Hunstad, David A; Dietzen, Dennis J

    2018-04-19

    Indoleamine-2,3-dioxygenase (IDO) catalyzes the first step of tryptophan (Trp) catabolism, yielding kynurenine (Kyn) metabolites. The kynurenine-to-tryptophan (K/T) ratio is used as a surrogate for biological IDO enzyme activity. IDO expression is increased during Escherichia coli urinary tract infection (UTI). Thus, our objective was to develop a method for measurement of Kyn/Trp ratio in human blood and urine and evaluate its use as a biomarker of UTI. A mass spectrometric method was developed to measure Trp and Kyn in serum and urine specimens. The method was applied to clinical urine specimens from symptomatic pediatric patients with laboratory-confirmed UTI or other acute conditions and from healthy controls. The liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was linear to 500 μmol/L for both Trp and Kyn. Imprecision ranged from 5 to 15% for Trp and 6-20% for Kyn. Analytical recoveries of Trp and Kyn ranged from 96 to 119% in serum and 90-97% in urine. No correlation was found between the K/T ratio and circulating IDO mass (r = 0.110) in serum. Urinary Kyn and Trp in the pediatric test cohort demonstrated elevations in the K/T ratio in symptomatic patients with UTI (median 13.08) and without UTI (median 14.38) compared to healthy controls (median 4.93; p < 0.001 for both comparisons). No significant difference in K/T ratio was noted between symptomatic patients with and without UTI (p = 0.84). Measurement of Trp and Kyn by LC-MS/MS is accurate and precise in serum and urine specimens. While urinary K/T ratio is not a specific biomarker for UTI, it may represent a general indicator of a systemic inflammatory process. Copyright © 2018 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  6. Prenatal inhibition of the kynurenine pathway leads to structural changes in the hippocampus of adult rat offspring.

    Science.gov (United States)

    Khalil, Omari S; Pisar, Mazura; Forrest, Caroline M; Vincenten, Maria C J; Darlington, L Gail; Stone, Trevor W

    2014-05-01

    Glutamate receptors for N-methyl-d-aspartate (NMDA) are involved in early brain development. The kynurenine pathway of tryptophan metabolism includes the NMDA receptor agonist quinolinic acid and the antagonist kynurenic acid. We now report that prenatal inhibition of the pathway in rats with 3,4-dimethoxy-N-[4-(3-nitrophenyl)thiazol-2-yl]benzenesulphonamide (Ro61-8048) produces marked changes in hippocampal neuron morphology, spine density and the immunocytochemical localisation of developmental proteins in the offspring at postnatal day 60. Golgi-Cox silver staining revealed decreased overall numbers and lengths of CA1 basal dendrites and secondary basal dendrites, together with fewer basal dendritic spines and less overall dendritic complexity in the basal arbour. Fewer dendrites and less complexity were also noted in the dentate gyrus granule cells. More neurons containing the nuclear marker NeuN and the developmental protein sonic hedgehog were detected in the CA1 region and dentate gyrus. Staining for doublecortin revealed fewer newly generated granule cells bearing extended dendritic processes. The number of neuron terminals staining for vesicular glutamate transporter (VGLUT)-1 and VGLUT-2 was increased by Ro61-8048, with no change in expression of vesicular GABA transporter or its co-localisation with vesicle-associated membrane protein-1. These data support the view that constitutive kynurenine metabolism normally plays a role in early embryonic brain development, and that interfering with it has profound consequences for neuronal structure and morphology, lasting into adulthood. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  7. Ecotropic murine leukemia virus-induced fusion of murine cells

    International Nuclear Information System (INIS)

    Pinter, A.; Chen, T.; Lowy, A.; Cortez, N.G.; Silagi, S.

    1986-01-01

    Extensive fusion occurs upon cocultivation of murine fibroblasts producing ecotropic murine leukemia viruses (MuLVs) with a large variety of murine cell lines in the presence of the polyene antibiotic amphotericin B, the active component of the antifungal agent Fungizone. The resulting polykaryocytes contain nuclei from both infected and uninfected cells, as evidenced by autoradiographic labeling experiments in which one or the other parent cell type was separately labeled with [ 3 H]thymidine and fused with an unlabeled parent. This cell fusion specifically requires the presence of an ecotropic MuLV-producing parent and is not observed for cells producing xenotropic, amphotropic, or dualtropic viruses. Mouse cells infected with nonecotropic viruses retain their sensitivity toward fusion, whereas infection with ecotropic viruses abrogates the fusion of these cells upon cocultivation with other ecotropic MuLV-producing cells. Nonmurine cells lacking the ecotropic gp70 receptor are not fused under similar conditions. Fusion is effectively inhibited by monospecific antisera to gp70, but not by antisera to p15(E), and studies with monoclonal antibodies identify distinct amino- and carboxy-terminal gp70 regions which play a role in the fusion reaction. The enhanced fusion which occurs in the presence of amphotericin B provides a rapid and sensitive assay for the expression of ecotropic MuLVs and should facilitate further mechanistic studies of MuLV-induced fusion of murine cells

  8. Análise sérica das enzimas aspartato aminotransferase, alanina aminotransferase e gama glutamiltranspeptidase de coelhos adultos tratados com extrato bruto de própolis

    Directory of Open Access Journals (Sweden)

    J. N. Ribeiro

    2009-01-01

    Full Text Available

    Diversos trabalhos têm atribuído a própolis inúmeras propriedades farmacológicas, dentre elas podemos citar, como exemplo, efeitos antibacteriano, antiviral, antiinflamatório, regenerador do tecido cartilaginoso, inibidor da formação de radicais livres e redutor de níveis sangüíneo de glicose e triacilglicerol. Alguns efeitos colaterais são atribuídos à própolis principalmente em doses elevadas. Muitos efeitos tóxicos da própolis são atribuídos ao álcool etílico presente no extrato.Dentre alguns efeitos tóxicos citados em literatura como realmente da própolis temos a dermatite e o aumento da uréia sangüínea. O presente estudo teve como objetivo investigar se o extrato bruto de própolis ocasiona algum efeito adverso nos níveis séricos de alanina aminotransferase, aspartato aminotransferase e gama – glutamiltranspeptidase de coelhos saudáveis. O experimento teve 30 dias de duração, sendo as dosagens dos constituintes do sangue (alanina aminotransferase, aspartato aminotransferase e gama – glutamiltranspeptidase realizadas a 0, 15 e 30 dias. Os resultados indicaram que, de o extrato bruto de própolis na forma testadea, não ocasionou alteração relevante nos níveis séricos das enzimas marcadoras de metabolismo hepático. Palavras-chave: Própolis, alanina aminotransferase, aspartato aminotransferase, gama glutamiltranpeptidase, toxicologia.

  9. Associations of White Blood Cell Count,Alanine Aminotransferase,and Aspartate Aminotransferase in the First Trimester withGestational Diabetes Mellitus.

    Science.gov (United States)

    Zhao, Li-li; Li, Wei; Ping, Fan; Ma, Liang-kun; Nie, Min

    2016-06-10

    Objective To explore the associations of white blood cell (WBC) count,alanine aminotransferase (ALT),and aspartate aminotransferase(AST) in the first trimester of pregnancy with gestational diabetes mellitus (GDM). Methods Totally 725 GDM women and 935 women who remained euglycemic throughout pregnancy were enrolled in this study. Pre-pregnancy weight/height were recorded. WBC,ALT,and AST levels were detected between 8 and 12 weeks of pregnancy.At 24 to 28 weeks of pregnancy,the glucose and insulin levels were measured. The WBC,ALT,and AST levels were compared between two groups,and the associations of WBC,ALT,and AST levels with the blood glucose and insulin levels were retrospectively analyzed. Meanwhile,the potential associations of those factors with the occurrence of GDM were analzyed. Results WBC count [9.41(8.15,10.84)?10(9)/L vs. 9.04 (7.64,10.37)?10(9)/L,P=1.0?10(-5)] and ALT levels [18.00(12.00,30.00)U/L vs. 16.00 (11.00,26.00)U/L,P=0.004] in the first trimester of pregnancy were significantly increased in GDM subjects than in normal glucose tolerance(NGT)subjects;however,the AST level showed no significant difference between these two groups [41.00 (26.00,43.00)U/L vs. 41.00 (23.00,43.00)U/L,P=0.588]. Logistic regression analysis illustrated that elevated WBC count was an independent risk factor for GDM after adjustment for age,pre-pregnancy body mass index,blood pressure,and family history of diabetes(OR=1.119,P=0.001). The ROC curve revealed that threshold of WBC count was 7.965?10(9)/L(AUC=0.566,P=1?10(-5)),which had a sensitivity of 79.4% and a specificity of 31.3%. Multivariate linear regression analysis showed that homeostasis model assessment of insulin resistance was positively correlated with WBC count(B=0.051,P=0.022,R(2)=0.083);1-hour blood glucose after oral 50 grams of sugar (B=0.044,P=0.001,R(2)=0.044) and fasting plasma true insulin(B=0.214,P=0.032,R(2)=0.066) were positively correlated with WBC count;1-hour true insulin after 100 grams

  10. Sensitive, specific radioisotope assay for L-glutamine-D-fructose-6- phosphat aminotransferase

    International Nuclear Information System (INIS)

    Callahan, M.; Tourian, A.; Hung, W.Y.

    1981-01-01

    A sensitive and specific radioassay for L-glutamine-D-fructose-6-phosphate aminotransferase (EC 5.3.1.19) activity is presented. Picomoles of product are measurable, and the assay can be applied to systems having limited quantities of available protein, particularly in extracts of either cell or organ cultures. The assay is at least 10,000 times more sensitive under K 1 concentrations of fructose 6-phosphate than the modified Elson-Morgan colorimetric assay and 20 times more sensitive under saturating conditions of fructose 6-phosphate. As little as 0.5 μg of cell-extract protein will yield measurable product. In contrast, 280 μg of crude-extract protein from colon is required with the modified Elson-Morgan colorimetric assay

  11. A gene duplication led to specialized gamma-aminobutyrate and beta-alanine aminotransferase in yeast

    DEFF Research Database (Denmark)

    Andersen, Gorm; Andersen, Birgit; Dobritzsch, D.

    2007-01-01

    and related yeasts have two different genes/enzymes to apparently 'distinguish' between the two reactions in a single cell. It is likely that upon duplication similar to 200 million years ago, a specialized Uga1p evolved into a 'novel' transaminase enzyme with broader substrate specificity.......In humans, beta-alanine (BAL) and the neurotransmitter gamma-aminobutyrate (GABA) are transaminated by a single aminotransferase enzyme. Apparently, yeast originally also had a single enzyme, but the corresponding gene was duplicated in the Saccharomyces kluyveri lineage. SkUGA1 encodes a homologue...... to characterize the substrate specificity and kinetic parameters of the four enzymes. It was found that the cofactor pyridoxal 5'-phosphate is needed for enzymatic activity and alpha-ketoglutarate, and not pyruvate, as the amino group acceptor. SkPyd4p preferentially uses BAL as the amino group donor (V...

  12. Structure and mechanism of a cysteine sulfinate desulfinase engineered on the aspartate aminotransferase scaffold.

    Science.gov (United States)

    Fernandez, Francisco J; de Vries, Dominique; Peña-Soler, Esther; Coll, Miquel; Christen, Philipp; Gehring, Heinz; Vega, M Cristina

    2012-02-01

    The joint substitution of three active-site residues in Escherichia coli (L)-aspartate aminotransferase increases the ratio of l-cysteine sulfinate desulfinase to transaminase activity 10(5)-fold. This change in reaction specificity results from combining a tyrosine-shift double mutation (Y214Q/R280Y) with a non-conservative substitution of a substrate-binding residue (I33Q). Tyr214 hydrogen bonds with O3 of the cofactor and is close to Arg374 which binds the α-carboxylate group of the substrate; Arg280 interacts with the distal carboxylate group of the substrate; and Ile33 is part of the hydrophobic patch near the entrance to the active site, presumably participating in the domain closure essential for the transamination reaction. In the triple-mutant enzyme, k(cat)' for desulfination of l-cysteine sulfinate increased to 0.5s(-1) (from 0.05s(-1) in wild-type enzyme), whereas k(cat)' for transamination of the same substrate was reduced from 510s(-1) to 0.05s(-1). Similarly, k(cat)' for β-decarboxylation of l-aspartate increased fromcat)' for transamination was reduced from 530s(-1) to 0.13s(-1). l-Aspartate aminotransferase had thus been converted into an l-cysteine sulfinate desulfinase that catalyzes transamination and l-aspartate β-decarboxylation as side reactions. The X-ray structures of the engineered l-cysteine sulfinate desulfinase in its pyridoxal-5'-phosphate and pyridoxamine-5'-phosphate form or liganded with a covalent coenzyme-substrate adduct identified the subtle structural changes that suffice for generating desulfinase activity and concomitantly abolishing transaminase activity toward dicarboxylic amino acids. Apparently, the triple mutation impairs the domain closure thus favoring reprotonation of alternative acceptor sites in coenzyme-substrate intermediates by bulk water. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. Clinical characteristics associated with hepatic steatosis on ultrasonography in patients with elevated alanine aminotransferase

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    Janaína Luz Narciso-Schiavon

    Full Text Available CONTEXT AND OBJECTIVE: The main causes of hepatic steatosis (HS are alcoholic liver disease and nonalcoholic fatty liver disease (NAFLD. Although liver biopsy is the gold standard for NAFLD diagnosis, the finding of abnormal aminotransferases in abstinent individuals, without known liver disease, suggests the diagnosis of NAFLD in 80-90% of the cases. Identification of clinical factors associated with HS on abdominal ultrasound may enable diagnoses of fatty liver non-invasively and cost-effectively. The aim here was to identify clinical variables associated with HS in individuals with elevated alanine aminotransferase (ALT levels. DESIGN AND SETTING: Cross-sectional study in a single tertiary care center. METHODS: Individuals with elevated ALT, serologically negative for hepatitis B and C, were evaluated by reviewing medical files. Patients who did not undergo abdominal ultrasonography were excluded. RESULTS: Among 94 individuals included, 40% presented HS on ultrasonography. Compared with individuals without HS, those with fatty liver were older (P = 0.043, with higher body mass index (BMI (P = 0.003, diabetes prevalence (P = 0.024, fasting glucose levels (P = 0.001 and triglycerides (P = 0.003. Multivariate analysis showed that BMI (odds ratio, OR = 1.186; 95% confidence interval, CI: 1.049-1.341; P = 0.006 and diabetes mellitus (OR = 12.721; 95% CI: 1.380-117.247; P = 0.025 were independently associated with HS. CONCLUSIONS: Simple clinical findings such as history of diabetes and high BMI may predict the presence of HS on ultrasonography in individuals with elevated ALT and negative serological tests for hepatitis.

  14. Irritable Bowel Syndrome May Be Associated with Elevated Alanine Aminotransferase and Metabolic Syndrome.

    Science.gov (United States)

    Lee, Seung Hwa; Kim, Kyu Nam; Kim, Kwang Min; Joo, Nam Seok

    2016-01-01

    Recent studies have revealed close relationships between hepatic injury, metabolic pathways, and gut microbiota. The microorganisms in the intestine also cause irritable bowel syndrome (IBS). The aim of this study was to examine whether IBS was associated with elevated hepatic enzyme [alanine aminotransferase (ALT) and aspartate aminotransferase (AST)], gamma-glutamyl transferase (γ-GT) levels, and metabolic syndrome (MS). This was a retrospective, cross-sectional, case-control study. The case and control groups comprised subjects who visited our health promotion center for general check-ups from June 2010 to December 2010. Of the 1127 initially screened subjects, 83 had IBS according to the Rome III criteria. The control group consisted of 260 age- and sex-matched subjects without IBS who visited our health promotion center during the same period. Compared to control subjects, patients with IBS showed significantly higher values of anthropometric parameters (body mass index, waist circumference), liver enzymes, γ-GT, and lipid levels. The prevalences of elevated ALT (16.9% vs. 7.7%; p=0.015) and γ-GT (24.1% vs. 11.5%; p=0.037) levels were significantly higher in patients with IBS than in control subjects. A statistically significant difference was observed in the prevalence of MS between controls and IBS patients (12.7% vs. 32.5%; p<0.001). The relationships between elevated ALT levels, MS, and IBS remained statistically significant after controlling for potential confounding factors. On the basis of our study results, IBS may be an important condition in certain patients with elevated ALT levels and MS.

  15. Regional adipose tissue and elevations in serum aminotransferases in HIV-infected individuals.

    Science.gov (United States)

    Tien, Phyllis C; Kotler, Donald P; Overton, E Turner; Lewis, Cora E; Rimland, David; Bacchetti, Peter; Scherzer, Rebecca; Gripshover, Barbara

    2008-06-01

    The association of fat distribution with alanine aminotransferase (ALT) and aspartate aminotransferase (AST) elevations is not well-defined in HIV-infected individuals. Obesity is associated with hepatic steatosis, and ALT is a marker of steatosis in the general population. Cross-sectional analysis of 1119 HIV-infected and 284 control subjects. Hepatitis C virus (HCV) RNA testing determined HCV infection. Magnetic resonance imaging measured regional adipose tissue volume. After adjustment for demographic and lifestyle factors, visceral adipose tissue (VAT) was positively associated with ALT in HIV/HCV-coinfected subjects (+9.8%, 95% confidence interval [CI]: 2.8 to 17.6), HIV-monoinfected subjects (+8.0%, 95% CI: 4.2 to 12.1), and controls (+5.9%, 95% CI: 2.0 to 10.1). In contrast, lower trunk subcutaneous adipose tissue (SAT) was negatively associated with ALT in HIV/HCV-coinfected subjects (-14.3%, 95% CI: -24.7 to -4.2) and HIV-monoinfected subjects (-11.9%, 95% CI: -18.4 to -5.3); there was a trend toward an association in controls (-7.1%, 95% CI: -22.7 to 5.9). Estimated associations between regional adipose tissue and AST were small and did not reach statistical significance. More VAT and less lower trunk SAT are associated with elevated ALT, which likely reflects the presence of steatosis. There was little association with AST. HCV infection and having more VAT or less lower trunk SAT are independently associated with elevated ALT in HIV infection. Study regarding the association between VAT, trunk SAT, HCV, and progression of steatosis and fibrosis is needed in HIV-infected individuals.

  16. Simultaneous determination of plasma creatinine, uric acid, kynurenine and tryptophan by high-performance liquid chromatography: method validation and in application to the assessment of renal function.

    Science.gov (United States)

    Zhao, Jianxing

    2015-03-01

    A high-performance liquid chromatography with ultraviolet detection method has been developed for the simultaneous determination of a set of reliable markers of renal function, including creatinine, uric acid, kynurenine and tryptophan in plasma. Separation was achieved by an Agilent HC-C18 (2) analytical column. Gradient elution and programmed wavelength detection allowed the method to be used to analyze these compounds by just one injection. The total run time was 25 min with all peaks of interest being eluted within 13 min. Good linear responses were found with correlation coefficient >0.999 for all analytes within the concentration range of the relevant levels. The recovery was: creatinine, 101 ± 1%; uric acid, 94.9 ± 3.7%; kynurenine, 100 ± 2%; and tryptophan, 92.6 ± 2.9%. Coefficients of variation within-run and between-run of all analytes were ≤2.4%. The limit of detection of the method was: creatinine, 0.1 µmol/L; uric acid, 0.05 µmol/L; kynurenine, 0.02 µmol/L; and tryptophan, 1 µmol/L. The developed method could be employed as a useful tool for the detection of chronic kidney disease, even at an early stage. Copyright © 2014 John Wiley & Sons, Ltd.

  17. Cloning and inactivation of a branched-chain-amino-acid aminotransferase gene from Staphylococcus carnosus and characterization of the enzyme

    DEFF Research Database (Denmark)

    Madsen, Søren M; Beck, Hans Christian; Ravn, Peter

    2002-01-01

    . The first step in the catabolism is most likely a transamination reaction catalyzed by BCAA aminotransferases (IlvE proteins). In this study, we cloned the ilvE gene from S. carnosus by using degenerate oligonucleotides and PCR. We found that the deduced amino acid sequence was 80% identical...... were essential for optimal cell growth....

  18. Gamma-glutamyltransferase, aspartate aminotransferase and alkaline phosphatase as markers of alcohol consumption in out-patient alcoholics

    DEFF Research Database (Denmark)

    Gluud, C; Andersen, I; Dietrichson, O

    1981-01-01

    and alkaline phosphatase in 18% and 7%. Neither the activity of gamma-glutamyltransferase, aspartate aminotransferase nor alkaline phosphatase showed any significant (P greater than 0.05) correlation with the history of alcohol consumption. The activities of gamma-glutamyltransferase and aspartate...

  19. Attention-deficit hyperactivity disorder (ADHD and glial integrity: S100B, cytokines and kynurenine metabolism - effects of medication

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    Schwarz Markus J

    2010-05-01

    Full Text Available Abstract Background Children with attention-deficit/hyperactivity disorder (ADHD show a marked temporal variability in their display of symptoms and neuropsychological performance. This could be explained in terms of an impaired glial supply of energy to support neuronal activity. Method We pursued one test of the idea with measures of a neurotrophin reflecting glial integrity (S100B and the influences of 8 cytokines on the metabolism of amino-acids, and of tryptophan/kynurenine to neuroprotective or potentially toxic products that could modulate glial function. Serum samples from 21 medication-naïve children with ADHD, 21 typically-developing controls, 14 medicated children with ADHD and 7 healthy siblings were analysed in this preliminary exploration of group differences and associations. Results There were no marked group differences in levels of S100B, no major imbalance in the ratios of pro- to anti-inflammatory interleukins nor in the metabolism of kynurenine to toxic metabolites in ADHD. However, four trends are described that may be worthy of closer examination in a more extensive study. First, S100B levels tended to be lower in ADHD children that did not show oppositional/conduct problems. Second, in medicated children raised interleukin levels showed a trend to normalisation. Third, while across all children the sensitivity to allergy reflected increased levels of IL-16 and IL-10, the latter showed a significant inverse relationship to measures of S100B in the ADHD group. Fourthly, against expectations healthy controls tended to show higher levels of toxic 3-hydroxykynurenine (3 HK than those with ADHD. Conclusions Thus, there were no clear signs (S100B that the glial functions were compromised in ADHD. However, other markers of glial function require examination. Nonetheless there is preliminary evidence that a minor imbalance of the immunological system was improved on medication. Finally, if lower levels of the potentially toxic 3

  20. A quest for normal values of serum aminotransferase and its association with age and body mass index

    International Nuclear Information System (INIS)

    Farooq, M.A.; Farooq, Y.; Khan, M.A.

    2016-01-01

    Objective: To determine the reference range for serum alanine aminotransferase (ALT) levels for young healthy individuals in our population and to find out effects of age and body mass index on alanine aminotransferase. Study Design: Descriptive cross sectional study. Place and Duration of Study: Military Hospital Rawalpindi; from Dec 2009 to April 2010. Material and Methods: Five hundred and fifty three young healthy adults were included in the study. Detailed history was taken. Parameters like Age, height and weight were measured. Relevant investigations were carried out for each subject which included blood complete picture, Chest X-Ray, ECG, Urine routine examination, liver function tests, serum urea, serum creatinine, serum uric acid, plasma glucose (F), Anti HCV antibodies, HBsAg, HIV antibodies and VDRL. Data was analyzed using SPSS version 22. Results: Age of subjects ranged from 19 to 50 years (29 +- 6) years, BMI 15.59 to 29.8, (21.58 +- 2). Serum alanine aminotransferase ranged from 17 to 81 IU/l, (29.9 +- 8) IU/l. Serum alanine aminotransferase for subjects with body mass index more than 25 Kg/m2 was 29.6 +- 7 IU/L. There is no significant difference in value of mean ALT overall and in those with BMI of more than 25 (p=0.149) Conclusion: Mean serum alanine aminotransferase value in young healthy adults included in this study was 29.9 +- 8 IU/L which is lower than normal reference provided at present which is 40 IU/l. Statistical analysis revealed that serum ALT is not significantly influenced by age and BMI. (author)

  1. [Association between occupational stress and aminotransferase activity in patients with metabolic syndrome].

    Science.gov (United States)

    Zhao, H; Song, L; Qiang, Y; Liu, H R; Qiu, F Y; Li, X Z; Song, H

    2016-12-20

    Objective: To investigate the association between occupational stress and activity of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in patients with metabolic syndrome. Methods: A case-control study was performed. According to inclusion and exclusion criteria, among the staff members of enterprises and public institutions aged 20~60 years who underwent physical examination in The Affiliated Hospital of Ningxia Medical University and The People's Hospital of Wuzhong from October 2011 to October 2012, 622 patients with metabolic syndrome who did not have a blood relationship with each other were enrolled as case group, and 600 healthy staff members who also did not have a blood relationshipwith each otherwere enrolled as control group. Questionnaire investigation, chronic occupational stress investigation, physical examination, and laboratory tests were performed for all subjects. Results: Compared with the control group, the case group had significantly higher serum levels and abnormal rates of AST and ALT ( t =-4.338 and-5.485, χ(2)=11.168 and 34.302, all P occupational stresses in both groups ( F =2.192 and 2.567, χ(2)=2.694 and 5.402, all P >0.05) , but there were significant differencesbetween the subgroups in all subjects ( F =5.005, χ(2)=6.398, all P occupational stresses in the case group, the control group, and all subjects ( F =0.845, 0.450, and 1.416, χ(2)=2.564, 1.344, and 3.147, all P >0.05) . The partial correlation analysis showed that the total score of occupational stress was positively correlated withthe serum level of AST ( r =0.071, P 0.05) , and that the serum level of AST was positively correlated with that of ALT ( r =0.736, P occupational stress was positively correlated with the serum level of AST ( r =0.069, P 0.05) , and the serum level of AST was positively correlated with that of ALT ( r =0.730, P occupational stress ( b =0.131, P =0.013) . Conclusion: Occupational stress is associated with increased serum level

  2. A modified HPLC method improves the simultaneous determination of plasma kynurenine and tryptophan concentrations in patients following maintenance hemodialysis

    Science.gov (United States)

    XIAO, CHENGGEN; CHEN, YUANHAN; LIANG, XINLING; XIE, ZHEN; ZHANG, MIN; LI, RUIZHAO; LI, ZHILIAN; FU, XIA; YU, XIYONG; SHI, WEI

    2014-01-01

    The ratio between plasma kynurenine (Kyn) and tryptophan (Trp) serves as a marker of indoleamine 2,3-dioxygenase, a critical immunomodulatory molecule. Simultaneous detection of the two markers may be performed using high-pressure liquid chromatography (HPLC). However, for uremic patients, the conventional detection method may be affected by a range of accumulated toxins. The current study aimed to establish a method for the simultaneous measurement of Kyn and Trp in patients following maintenance hemodialysis via HPLC-ultraviolet detection. The procedure involved the use of a SinoChrom ODS-BP C18 column (4.6×150 mm; inner diameter, 4.5 μm) and a mobile phase of 15 mmol/l sodium acetate acetic acid solution (containing 5% acetonitrile, pH 4.8). The modified method was verified using plasma samples from 10 healthy controls and 91 maintenance hemodialysis patients. The results demonstrated that the modified method was successful in simultaneously detecting the concentrations of Trp and Kyn in the healthy controls and maintenance hemodialysis patients. The method is simple, fast, accurate and suitable for clinical and research purposes in maintenance hemodialysis patients. PMID:24669249

  3. Untargeted metabolomics of colonic digests reveals kynurenine pathway metabolites, dityrosine and 3-dehydroxycarnitine as red versus white meat discriminating metabolites

    Science.gov (United States)

    Rombouts, Caroline; Hemeryck, Lieselot Y.; Van Hecke, Thomas; De Smet, Stefaan; De Vos, Winnok H.; Vanhaecke, Lynn

    2017-01-01

    Epidemiological research has demonstrated that the consumption of red meat is an important risk factor for the development of colorectal cancer (CRC), diabetes mellitus and cardiovascular diseases. However, there is no holistic insight in the (by-) products of meat digestion that may contribute to disease development. To address this hiatus, an untargeted mass spectrometry (MS)-based metabolomics approach was used to create red versus white meat associated metabolic fingerprints following in vitro colonic digestion using the fecal inocula of ten healthy volunteers. Twenty-two metabolites were unequivocally associated with simulated colonic digestion of red meat. Several of these metabolites could mechanistically be linked to red meat-associated pathways including N’-formylkynurenine, kynurenine and kynurenic acid (all involved in tryptophan metabolism), the oxidative stress marker dityrosine, and 3-dehydroxycarnitine. In conclusion, the used MS-based metabolomics platform proved to be a powerful platform for detection of specific metabolites that improve the understanding of the causal relationship between red meat consumption and associated diseases. PMID:28195169

  4. Influence of ovarian hormones on cortical spreading depression and its suppression by L-kynurenine in rat.

    Directory of Open Access Journals (Sweden)

    Virginie Chauvel

    Full Text Available Migraine is sexually dimorphic and associated in 20-30% of patients with an aura most likely caused by cortical spreading depression (CSD. We have previously shown that systemic L-kynurenine (L-KYN, the precursor of kynurenic acid, suppresses CSD and that this effect depends on the stage of the estrous cycle in female rats. The objectives here are to determine the influence of ovarian hormones on KCl-induced CSD and its suppression after L-KYN by directly modulating estradiol or progesterone levels in ovariectomized rats. Adult female rats were ovariectomized and subcutaneously implanted with silastic capsules filled with progesterone or 17β-estradiol mixed with cholesterol, with cholesterol only or left empty. Two weeks after the ovariectomy/capsule implantation, the animals received an i.p. injection of L-KYN (300 mg/kg or NaCl as control. Thirty minutes later CSDs were elicited by applying KCl over the occipital cortex and recorded by DC electrocorticogram for 1 hour. The results show that both estradiol and progesterone increase CSD frequency after ovariectomy. The suppressive effect of L-KYN on CSD frequency, previously reported in normal cycling females, is not found anymore after ovariectomy, but reappears after progesterone replacement therapy. Taken together, these results emphasize the complex role of sex hormones on cortical excitability. The CSD increase by estradiol and, more surprisingly, progesterone may explain why clinically migraine with aura appears or worsens during pregnancy or with combined hormonal treatments.

  5. Inactivation of γ-aminobutyric acid aminotransferase by γ-ethynyl- and γ-vinyl GABA

    International Nuclear Information System (INIS)

    Silverman, R.B.; Burke, J.R.; Nanavati, S.M.

    1989-01-01

    γ-Ethynyl- and γ-vinyl GABA (vigabatrin) are anticonvulsant agents that have been shown to be mechanism-based inactivators of γ-aminobutyric acid aminotransferase (GABA-T). The inactivation mechanisms of these compounds have been investigated. Inactivation of GABA-T by [ 3 H]γ-ethynyl GABA led to the incorporation of 1.0 equiv of 3 H into the enzyme which is not released by enzyme denaturation. Inactivation by γ-ethynyl GABA of GABA-T reconstituted with [ 3 H]PLP followed by denaturation resulted in release of 3 H as PLP. Eight different possible adducts are consistent with that result. Experiments have been carried out to differentiate these possibilities. Similar studies have been carried out with γ-vinyl GABA. Inactivation by [ 14 C]γ-vinyl GABA resulted in the incorporation of 1.0 equiv of 14 C per active site. Unlike the case with γ-ethynyl GABA, γ-vinyl GABA inactivation of GABA-T reconstituted with [ 3 H]PLP followed by denaturation resulted in release of 3 H as PMP

  6. Tumor-promoting phorbol ester amplifies the inductions of tyrosine aminotransferase and ornithine decarboxylase by glucocorticoid

    International Nuclear Information System (INIS)

    Kido, H.; Fukusen, N.; Katunuma, N.

    1987-01-01

    In adrenalectomized rats, the tumor-promoting phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA) markedly enhanced the inductions of tyrosine aminotransferase (TAT) and ornithine decarboxylase by glucocorticoids, even with sufficient concentration of glucocorticoids to have a maximal effect, whereas it had no effect on TAT activity and increased ornithine decarboxylase activity only slightly in the absence of glucocorticoids. Phorbol derivatives and components of TPA such as 4β-phorbol, phorbol 12-tetradecanoate, phorbol 13-acetate, and 4-O-methylphorbol 12-tetradecanoate 13-acetate, which have no tumor-promoting activity or ability to activate protein kinase C, did not have any effect on TAT induction by glucocorticoid. TPA enhanced the induction of TAT by various glucocorticoids but had no effect on induction of TAT by glucagon or insulin and did not enhance the induction of glucose-6-phosphate dehydrogenase by 17β-estradiol. These results suggest that TPA specifically enhances the induction of TAT and ornithine decarboxylase by glucocorticoids. Similar effects of TPA on TAT induction by glucocorticoid were observed in primary cultures of adult rat hepatocytes. Another activator of protein kinase C, rac-1,2-dioctanoylglycerol, was also found to have similar effects on the cells

  7. Jasmonate is involved in the induction of tyrosine aminotransferase and tocopherol biosynthesis in Arabidopsis thaliana.

    Science.gov (United States)

    Sandorf, Iris; Holländer-Czytko, Heike

    2002-11-01

    Coronatine-inducible tyrosine aminotransferase (TAT), which catalyses the transamination from tyrosine to p-hydroxyphenylpyruvate, is the first enzyme of a pathway leading via homogentisic acid to plastoquinone and tocopherols, the latter of which are known to be radical scavengers in plants. TAT can be also induced by the octadecanoids methyl jasmonate (MeJA) and methyl-12-oxophytodienoic acid (MeOPDA), as well as by wounding, high light, UV light and the herbicide oxyfluorfen. In order to elucidate the role of octadecanoids in the process of TAT induction in Arabidopsis thaliana (L.) Heynh., the jasmonate-deficient mutant delayed dehiscence (dde1) was used, in which the gene for 12-oxophytodienoic acid reductase 3 is disrupted. The amount of immunodetectable TAT was low. The enzyme was still fully induced by coronatine as well as by MeJA although induction by the latter was to a lesser extent and later than in the wild type. Treatment with MeOPDA, wounding and UV light, however, had hardly any effects. Tocopherol levels that showed considerable increases in the wild type after some treatments were much less affected in the mutant. However, starting levels of tocopherol were higher in non-induced dde1 than in the wild type. We conclude that jasmonate plays an important role in the signal transduction pathway regulating TAT activity and the biosynthesis of its product tocopherol.

  8. Prevalence and predictors of alanine aminotransferase elevation among normal weight, overweight and obese youth in Mexico.

    Science.gov (United States)

    Purcell, Maura; Flores, Yvonne N; Zhang, Zuo-Feng; Denova-Gutiérrez, Edgar; Salmeron, Jorge

    2013-09-01

    This study aimed to determine the prevalence of and risk factors associated with elevated alanine aminotransferase (ALT) levels among a sample of normal weight, overweight and obese youth from two urban populations in Central Mexico. Baseline data from 1262 youth aged 8-19 years who participated in the Mexican Health Worker Cohort Study from March 2004 to April 2006 were reviewed, including 680 girls and 582 boys, with a total of 83 participants with elevated ALT level (>40 U/L). Information was obtained from self-administered questionnaires, anthropometric results and clinical measurements. Associations of interest were examined using multivariate logistic regression models. A total of 3.8% of girls and 9.8% of boys had elevated ALT levels. Elevated ALT was observed in 28.9% of the obese and 14.2% of the overweight participants. Metabolic syndrome (MS) occurred in 6.1% of the study population and those with MS had a high percentage of elevated ALT (14.5% of girls and 40.0% of boys, respectively). Abdominal obesity and insulin resistance were also associated with a greater risk of elevated ALT. Obesity and certain metabolic risk factors are important predictors for elevated ALT. Screening for ALT levels in obese youth could help to identify those at risk and reduce the possibility of future liver diseases. © 2013 Wiley Publishing Asia Pty Ltd and Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine.

  9. Diversification of Transcriptional Regulation Determines Subfunctionalization of Paralogous Branched Chain Aminotransferases in the Yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    González, James; López, Geovani; Argueta, Stefany; Escalera-Fanjul, Ximena; El Hafidi, Mohammed; Campero-Basaldua, Carlos; Strauss, Joseph; Riego-Ruiz, Lina; González, Alicia

    2017-11-01

    Saccharomyces cerevisiae harbors BAT1 and BAT2 paralogous genes that encode branched chain aminotransferases and have opposed expression profiles and physiological roles . Accordingly, in primary nitrogen sources such as glutamine, BAT1 expression is induced, supporting Bat1-dependent valine-isoleucine-leucine (VIL) biosynthesis, while BAT2 expression is repressed. Conversely, in the presence of VIL as the sole nitrogen source, BAT1 expression is hindered while that of BAT2 is activated, resulting in Bat2-dependent VIL catabolism. The presented results confirm that BAT1 expression is determined by transcriptional activation through the action of the Leu3-α-isopropylmalate (α-IPM) active isoform, and uncovers the existence of a novel α-IPM biosynthetic pathway operating in a put3 Δ mutant grown on VIL, through Bat2-Leu2-Leu1 consecutive action. The classic α-IPM biosynthetic route operates in glutamine through the action of the leucine-sensitive α-IPM synthases. The presented results also show that BAT2 repression in glutamine can be alleviated in a ure2 Δ mutant or through Gcn4-dependent transcriptional activation. Thus, when S. cerevisiae is grown on glutamine, VIL biosynthesis is predominant and is preferentially achieved through BAT1 ; while on VIL as the sole nitrogen source, catabolism prevails and is mainly afforded by BAT2 . Copyright © 2017 by the Genetics Society of America.

  10. Measurement and purification of Alanine aminotransferase (ALT enzyme activity in patients with celiac disease

    Directory of Open Access Journals (Sweden)

    Taghreed U. Mohammed

    2017-09-01

    Full Text Available Celiac disease (CD is the most common genetically - based disease in correlation with food intolerance. The aim of this study is to measure the activity of ALT enzyme and purify enzyme from sera women with celiac disease. Alanine aminotransferase (ALT activity has been assayed in (30 women serum samples with celiac disease, age range between (20-40 year and (30 serum of healthy women as control group, age range between (22-38 year. In the present study, the mean value of ALT activity was significantly higher in patients with celiac disease than healthy group (p<0.01. The ALT enzyme was partial purified from sera women with celiac disease by dialysis, gel filtration using Sephadex G- 50 and ion exchange chromatography using DEAE- cellulose A-50 . The results showed a single peak by using gel filtration and the activity reached 31-15 U/L .Two isoenzymes were obtained by using ion exchange chromatography and the purity degree of isoenzymse (I, II were (5.7 and (5.53 fold respectively

  11. Theoretical studies on the inactivation mechanism of γ-aminobutyric acid aminotransferase.

    Science.gov (United States)

    Durak, A T; Gökcan, H; Konuklar, F A S

    2011-07-21

    The inactivation mechanism of γ-aminobutyric acid aminotransferase (GABA-AT) in the presence of γ-vinyl-aminobutyric acid, an anti-epilepsy drug, has been studied by means of theoretical calculations. Density functional theory methods have been applied to compare the three experimentally proposed inactivation mechanisms (Silverman et al., J. Biol. Chem., 2004, 279, 363). All the calculations were performed at the B3LYP/6-31+G(d,p) level of theory. Single point solvent calculations were carried out in water, by means of an integral equation formalism-polarizable continuum model (IEFPCM) at the B3LYP/6-31+G(d,p) level of theory. The present calculations provide an insight into the mechanistic preferences of the inactivation reaction of GABA-AT. The results also allow us to elucidate the key factors behind the mechanistic preferences. The computations also confirm the importance of explicit water molecules around the reacting center in the proton transfer steps.

  12. Design and mechanism of tetrahydrothiophene-based γ-aminobutyric acid aminotransferase inactivators.

    Science.gov (United States)

    Le, Hoang V; Hawker, Dustin D; Wu, Rui; Doud, Emma; Widom, Julia; Sanishvili, Ruslan; Liu, Dali; Kelleher, Neil L; Silverman, Richard B

    2015-04-08

    Low levels of γ-aminobutyric acid (GABA), one of two major neurotransmitters that regulate brain neuronal activity, are associated with many neurological disorders, such as epilepsy, Parkinson's disease, Alzheimer's disease, Huntington's disease, and cocaine addiction. One of the main methods to raise the GABA level in human brain is to use small molecules that cross the blood-brain barrier and inhibit the activity of γ-aminobutyric acid aminotransferase (GABA-AT), the enzyme that degrades GABA. We have designed a series of conformationally restricted tetrahydrothiophene-based GABA analogues with a properly positioned leaving group that could facilitate a ring-opening mechanism, leading to inactivation of GABA-AT. One compound in the series is 8 times more efficient an inactivator of GABA-AT than vigabatrin, the only FDA-approved inactivator of GABA-AT. Our mechanistic studies show that the compound inactivates GABA-AT by a new mechanism. The metabolite resulting from inactivation does not covalently bind to amino acid residues of GABA-AT but stays in the active site via H-bonding interactions with Arg-192, a π-π interaction with Phe-189, and a weak nonbonded S···O═C interaction with Glu-270, thereby inactivating the enzyme.

  13. A Micro-Platinum Wire Biosensor for Fast and Selective Detection of Alanine Aminotransferase

    Directory of Open Access Journals (Sweden)

    Tran Nguyen Thanh Thuy

    2016-05-01

    Full Text Available In this study, a miniaturized biosensor based on permselective polymer layers (overoxidized polypyrrole (Ppy and Nafion® modified and enzyme (glutamate oxidase (GlutOx immobilized micro-platinum wire electrode for the detection of alanine aminotransferase (ALT was fabricated. The proposed ALT biosensor was measured electrochemically by constant potential amperometry at +0.7 V vs. Ag/AgCl. The ALT biosensor provides fast response time (~5 s and superior selectivity towards ALT against both negatively and positively charged species (e.g., ascorbic acid (AA and dopamine (DA, respectively. The detection range of the ALT biosensor is found to be 10–900 U/L which covers the range of normal ALT levels presented in the serum and the detection limit and sensitivity are found to be 8.48 U/L and 0.059 nA/(U/L·mm2 (N = 10, respectively. We also found that one-day storage of the ALT biosensor at −20 °C right after the sensor being fabricated can enhance the sensor sensitivity (1.74 times higher than that of the sensor stored at 4 °C. The ALT biosensor is stable after eight weeks of storage at −20 °C. The sensor was tested in spiked ALT samples (ALT activities: 20, 200, 400, and 900 U/L and reasonable recoveries (70%~107% were obtained.

  14. Molecular basis of ornithine aminotransferase deficiency in B-6-responsive and -nonresponsive forms of gyrate atrophy

    International Nuclear Information System (INIS)

    Ramesh, V.; McClatchey, A.I.; Ramesh, N.; Benoit, L.A.; Berson, E.L.; Shih, V.E.; Gusella, J.F.

    1988-01-01

    Gyrate atrophy (GA), a recessive eye disease involving progressive loss of vision due to chorioretinal degeneration, is associated with a deficiency of the mitochondrial enzyme ornithine aminotransferase with consequent hyperornithinemia. Genetic heterogeneity of GA has been suggested by the demonstration that administration of pyridoxine to increase the level of pyridoxal phosphate, a cofactor of OATase, reduces hyperornithinemia in a subset of patients. The authors have cloned and sequences cDNAs for OATase from two GA patients, one responsive and one nonresponsive to pyridoxine treatment. The respective cDNAs contained different single missense mutations, which were sufficient to eliminate OATase activity when each cDNA was tested in a eukaryotic expression system. However, like the enzyme in fibroblasts from the pyridoxine-responsive patient, OATase encoded by the corresponding cDNA from this individual showed a significant increase in activity when assayed in the presence of an increased pyridoxal phosphate concentration. These data firmly establish that both pyridoxine responsive and nonresponsive forms of GA result from mutations in the OATase structural gene. Moreover, they provide a molecular characterization of the primary lesion in a pyridoxine-responsive genetic disorder

  15. Aspartate aminotransferase: the kinetic barriers facing the covalent intermediates on the reaction pathway

    International Nuclear Information System (INIS)

    Kirsch, J.F.; Julin, D.A.; McLeish, M.; Wiesinger, H.

    1986-01-01

    The intermediates, aldimine (A), quinonoid (Q) and ketimine (K), along the transaminase reaction coordinate were probed by isotope transfer and solvent exchange kinetics. Less than 0.003% of 3 H is transferred from C/sub α/[ 3 H]-aspartate to pyridoxamine phosphate in the cytoplasmic aspartate aminotransferase (cAATase) reaction implying either that Q does not exist as a kinetically competent intermediate or that there is a rapid exchange of isotope with solvent. The ratio of the rate constants for C/sub α/ hydrogen exchange vs keto acid product formation (k/sub exge//k/sub prod/) are 2.5 and 0.5 for the reactions of cAATase with C/sub α/ [ 2 H]-aspartate and mitochondrial (m) AATase with C/sub α/[ 2 H]-glutamate respectively. The latter reaction was also probed from the α-keto-glutarate side with carbonyl 0-18 enriched keto acid. This experiment gave k/sub exge//k/sub prod/ = 1.0 for oxygen-18 exchange in α-ketoglutarate versus amino acid formation. The two exchange experiments with mAATase are interpreted in terms of a model in which the rate constant for diffusion of water from the active site is comparable with those for product forming steps

  16. Endocannabinoid receptor blockade reduces alanine aminotransferase in polycystic ovary syndrome independent of weight loss.

    Science.gov (United States)

    Dawson, Alison J; Kilpatrick, Eric S; Coady, Anne-Marie; Elshewehy, Abeer M M; Dakroury, Youssra; Ahmed, Lina; Atkin, Stephen L; Sathyapalan, Thozhukat

    2017-07-14

    Evidence suggests that endocannabinoid system activation through the cannabinoid receptor 1 (CB1) is associated with enhanced liver injury, and CB1 antagonism may be beneficial. The aim of this study was to determine the impact of rimonabant (CB1 antagonist) on alanine aminotransferase (ALT), a hepatocellular injury marker, and a hepatic inflammatory cytokine profile. Post hoc review of 2 studies involving 50 obese women with PCOS and well matched for weight, randomised to weight reducing therapy; rimonabant (20 mg od) or orlistat (120 mg tds), or to insulin sensitising therapy metformin, (500 mg tds), or pioglitazone (45 mg od). No subject had non-alcoholic fatty liver disease (NAFLD). Treatment with rimonabant for 12 weeks reduced both ALT and weight (p weight. There was a significant reduction of weight with orlistat (p weight loss and hepatic inflammatory markers in obese women with PCOS without NAFLD. ISRCTN58369615 (February 2007; retrospectively registered) ISRCTN75758249 (October 2007; retrospectively registered).

  17. Design and Mechanism of Tetrahydrothiophene-Based γ-Aminobutyric Acid Aminotransferase Inactivators

    Energy Technology Data Exchange (ETDEWEB)

    Le, Hoang V. [Departments; Hawker, Dustin D. [Departments; Wu, Rui [Department; Doud, Emma [Departments; Widom, Julia [Departments; Sanishvili, Ruslan [X-ray; Liu, Dali [Department; Kelleher, Neil L. [Departments; Silverman, Richard B. [Departments

    2015-03-25

    Low levels of gamma-aminobutyric acid (GABA), one of two major neurotransmitters that regulate brain neuronal activity, are associated with many neurological disorders, such as epilepsy, Parkinsons disease, Alzheimers disease, Huntingtons disease, and cocaine addiction. One of the main methods to raise the GABA level in human brain is to use small molecules that cross the bloodbrain barrier and inhibit the activity of gamma-aminobutyric acid aminotransferase (GABA-AT), the enzyme that degrades GABA. We have designed a series of conformationally restricted tetrahydrothiophene-based GABA analogues with a properly positioned leaving group that could facilitate a ring-opening mechanism, leading to inactivation of GABA-AT. One compound in the series is 8 times more efficient an inactivator of GABA-AT than vigabatrin, the only FDA-approved inactivator of GABA-AT. Our mechanistic studies show that the compound inactivates GABA-AT by a new mechanism. The metabolite resulting from inactivation does not covalently bind to amino acid residues of GABA-AT but stays in the active site via H-bonding interactions with Arg-192, a pi-pi interaction with Phe-189, and a weak nonbonded (SO)-O-...=C interaction with Glu-270, thereby inactivating the enzyme.

  18. Identification of factors for physicians to facilitate early differential diagnosis of scrub typhus, murine typhus, and Q fever from dengue fever in Taiwan.

    Science.gov (United States)

    Chang, Ko; Lee, Nan-Yao; Ko, Wen-Chien; Tsai, Jih-Jin; Lin, Wei-Ru; Chen, Tun-Chieh; Lu, Po-Liang; Chen, Yen-Hsu

    2017-02-01

    Dengue fever, rickettsial diseases, and Q fever are acute febrile illnesses with similar manifestations in tropical areas. Early differential diagnosis of scrub typhus, murine typhus, and Q fever from dengue fever may be made by understanding the distinguishing clinical characteristics and the significance of demographic and weather factors. We conducted a retrospective study to identify clinical, demographic, and meteorological characteristics of 454 dengue fever, 178 scrub typhus, 143 Q fever, and 81 murine typhus cases in three Taiwan hospitals. Case numbers of murine typhus and Q fever correlated significantly with temperature and rainfall; the scrub typhus case number was only significantly related with temperature. Neither temperature nor rainfall correlated with the case number of dengue fever. The rarity of dengue fever cases from January to June in Taiwan may be a helpful clue for diagnosis in the area. A male predominance was observed, as the male-to-female rate was 2.1 for murine typhus and 7.4 for Q fever. Multivariate analysis revealed the following six important factors for differentiating the rickettsial diseases and Q fever group from the dengue fever group: fever ≥8 days, alanine aminotransferase > aspartate aminotransferase, platelets >63,000/mL, C-reactive protein >31.9 mg/L, absence of bone pain, and absence of a bleeding syndrome. Understanding the rarity of dengue in the first half of a year in Taiwan and the six differentiating factors may help facilitate the early differential diagnosis of rickettsial diseases and Q fever from dengue fever, permitting early antibiotic treatment. Copyright © 2015. Published by Elsevier B.V.

  19. Imported rickettsioses : think of murine typhus

    NARCIS (Netherlands)

    van der Kleij, FGH; Gansevoort, RT; Kreeftenberg, HG

    Murine typhus is a disease still prevalent in many parts of the world. Because the incidence in the US and Europe has declined rapidly, physicians in these continents have become unfamiliar with the clinical picture. Murine typhus is associated with significant morbidity and fatalities do occur,

  20. Modifiable clinical and lifestyle factors are associated with elevated alanine aminotransferase levels in newly diagnosed type 2 diabetes patients

    DEFF Research Database (Denmark)

    Mor, Anil; Svensson, Elisabeth; Rungby, Jørgen

    2014-01-01

    BACKGROUND: Current literature lacks data on markers of non-alcoholic fatty liver disease (NAFLD) in newly diagnosed type 2 diabetes mellitus (T2DM) patients. We therefore, conducted a cross-sectional study to examine modifiable clinical and lifestyle factors associated with elevated alanine...... aminotransferase (ALT) levels as a marker of NAFLD in new T2DM patients. METHODS: Alanine aminotransferase levels were measured in 1026 incident T2DM patients enrolled in the nationwide Danish Centre for Strategic Research in Type 2 Diabetes (DD2) cohort. We examined prevalence of elevated ALT (>38 IU/L for women....../L (interquartile range: 22-41 IU/L) in men. Elevated ALT was found in 16% of incident T2DM patients. The risk of elevated ALT was increased in patients who were diabetes debut [adjusted prevalence ratio (aPR): 1.96, 95% confidence interval (CI): 1.15-3.33], in those with alcohol overuse (>14...

  1. Clinical significance of elevated serum aminotransferases levels in asymptomatic individuals with hepatitis C infection

    International Nuclear Information System (INIS)

    Nafees, M.; Ditta, A.; Jafferi, G.

    2010-01-01

    Background: Hepatitis C is a common and important cause of chronic liver disease that often remains asymptomatic and most of the times discovered incidentally by routine serologic or biochemical testing. Aminotransferases (AST and ALT) reflect alterations in liver function/inflammation in liver diseases. The current study was conducted to examine the utilization and limitations of these biochemical markers in subjects with asymptomatic HCV infection. Aims and Objectives: To find out how many subjects with asymptomatic HCV infection have normal or elevated serum AST and ALT levels. Subjects and Methods: Study Design: Cross sectional. Study Duration: Seven months from November 2008 to July 2009. Study Universe: Services Hospital, Lahore. Study Population: This study included 413 subjects attending the outpatient departments of hospital with minor complaints. The random population of subjects was referred to the clinical laboratory of Services Hospital, Lahore for LFTs, HBsAg and anti-HCV screening from OPD department of the hospital. A total of 413 persons of all ages were analyzed during this study. There were 263 subjects who were sero - positive for anti-HCV (141 females, 122 males; median age 35 +- 11.34 years) and 150 in the control group (80 of them were females and 70 males with median age 32 +- 12.97 years) were sero-negative for both HBsAg and anti - HCV. Subjects Selection Criteria: In this study, only anti - HCV sero - positive subjects were included who was sero - negative for HBsAg or dual infection (both HBsAg and anti - HCV) and not on anti - viral therapy. Control group was sero - negative for both - HBsAg and anti - HCV antibodies. Data Collection: We assayed levels of serum aminotransferases (AST and ALT) and screened blood for HBsAg and anti-HCV. ELISA technique was used for viral hepatitis markers. Results: Out of 263 subjects tested positive for anti-HCV antibodies in their blood, 90.76 % and 87.45 % had elevated AST and ALT levels (ALT = 40 U

  2. Relaxed evolution in the tyrosine aminotransferase gene tat in old world fruit bats (Chiroptera: Pteropodidae).

    Science.gov (United States)

    Shen, Bin; Fang, Tao; Yang, Tianxiao; Jones, Gareth; Irwin, David M; Zhang, Shuyi

    2014-01-01

    Frugivorous and nectarivorous bats fuel their metabolism mostly by using carbohydrates and allocate the restricted amounts of ingested proteins mainly for anabolic protein syntheses rather than for catabolic energy production. Thus, it is possible that genes involved in protein (amino acid) catabolism may have undergone relaxed evolution in these fruit- and nectar-eating bats. The tyrosine aminotransferase (TAT, encoded by the Tat gene) is the rate-limiting enzyme in the tyrosine catabolic pathway. To test whether the Tat gene has undergone relaxed evolution in the fruit- and nectar-eating bats, we obtained the Tat coding region from 20 bat species including four Old World fruit bats (Pteropodidae) and two New World fruit bats (Phyllostomidae). Phylogenetic reconstructions revealed a gene tree in which all echolocating bats (including the New World fruit bats) formed a monophyletic group. The phylogenetic conflict appears to stem from accelerated TAT protein sequence evolution in the Old World fruit bats. Our molecular evolutionary analyses confirmed a change in the selection pressure acting on Tat, which was likely caused by a relaxation of the evolutionary constraints on the Tat gene in the Old World fruit bats. Hepatic TAT activity assays showed that TAT activities in species of the Old World fruit bats are significantly lower than those of insectivorous bats and omnivorous mice, which was not caused by a change in TAT protein levels in the liver. Our study provides unambiguous evidence that the Tat gene has undergone relaxed evolution in the Old World fruit bats in response to changes in their metabolism due to the evolution of their special diet.

  3. Expression and Bioinformatic Analysis of Ornithine Aminotransferase 
in Non-small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Danfei ZHOU

    2012-09-01

    Full Text Available Background and objective It has been proven that ornithine aminotransferase (OAT might play an important role in the oncogenesis and progression of numerous malignant tumors. The aim of this study is to detect the mRNA and protein expression of OAT in non-small cell lung cancer (NSCLC, as well as to analyze the bioinformatic features and binary interactions. Methods OAT mRNA expression was detected in A549 and 16HBE cell lines by reverse transcription-polymerase chain reaction. OAT protein expression was determined in 55 cases of NSCLC and 17 cases of adjacent non-tumor lung tissues by immunohistochemical staining. The bioinformatic features and binary interactions of OAT were analyzed. Gene ontology annotation and signal pathway analysis were performed. Results OAT mRNA expression in A549 cells was 2.85-fold lower than that in 16HBE cells. OAT protein expression was significantly higher in NSCLC tissues than that in adjacent non-tumor lung tissues. A significant difference of OAT protein expression was existed between squamous cell lung cancer and adenocarcinoma (P<0.05, but was not correlated with the gender, age, lymph node metastasis, tumor size, and TNM stages. Bioinformatic analysis suggested that OAT was a highly homologous and stable protein located in the mitochondria. An aminotran-3 domain and several sites of phosphorylation, which may function in signal transduction, gene transcription, and molecular transit, were found. In the 54 selected binary interactions of OAT, TNF and TRAF6 play roles in the NF-κB pathway. Conclusion OAT may play an important role in the oncogenesis and progression of NSCLC. Thus, OAT may be a novel biomarker for the diagnosis of NSCLC or a new target for its treatment.

  4. High serum alanine aminotransferase is associated with the risk of colorectal adenoma in Korean men.

    Science.gov (United States)

    Moon, Chang Mo; Yun, Kyung Eun; Ryu, Seungho; Chang, Yoosoo; Park, Dong Il

    2017-07-01

    An elevated alanine aminotransferase (ALT) is frequently observed in subjects with metabolic syndrome, which is associated with the risk of colorectal adenoma (CRA). However, the relationship between ALT and CRA remains unclear. Therefore, we aimed to investigate whether high serum ALT is associated with the risk of CRA in a metabolically healthy population. We conducted this cross-sectional study in 27,717 asymptomatic Korean adults who underwent a health checkup. Subjects were categorized as adenoma-free, hyperplastic polyp, low-risk adenoma, or high-risk adenoma. High-risk adenoma was defined as three or more adenomas, any adenoma ≥ 10 mm, or adenoma with high-grade dysplasia or villous features. Among all participants, 10.3% and 1.5% of cases were categorized as low-risk and high-risk adenoma, respectively. In multivariate analyses adjusting for age, sex, body mass index, smoking habits, alcohol intake, regular exercise, aspirin and analgesics use, family history of colon cancer, education level, fatty liver, high-sensitivity C reactive protein, homeostasis model assessment of insulin resistance, total cholesterol, and triglyceride, an increase in ALT was positively associated with the prevalence of low-risk and high-risk adenoma (P for trend = 0.029 and 0.027, respectively). The highest quartile group of ALT level showed a significantly increased prevalence in low-risk (odds ratio, 1.17) and high-risk adenoma (odds ratio, 1.48) groups compared with the lowest quartile group. This phenomenon persisted in the subgroup analysis in men, but not in women. In the asymptomatic healthy population, high serum ALT is significantly associated with the risk of CRA. © 2016 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.

  5. Elevated alanine aminotransferase independently predicts new onset of depression in employees undergoing health screening examinations.

    Science.gov (United States)

    Zelber-Sagi, S; Toker, S; Armon, G; Melamed, S; Berliner, S; Shapira, I; Halpern, Z; Santo, E; Shibolet, O

    2013-12-01

    Non-alcoholic fatty liver disease (NAFLD) is the most common cause of elevated alanine aminotransferase (ALT). NAFLD is associated with insulin resistance and hepatic inflammation. Similarly, patients with depression exhibit insulin resistance and increased inflammatory markers. However, no study has shown a clear association between elevated ALT and the development of depression. The aim of the study was to test whether elevated ALT, a surrogate marker for NAFLD, predicts the development of depression. The present prospective cohort study investigated 12 180 employed adults referred for health examinations that included fasting blood tests and anthropometric measurements between 2003 and 2010. Exclusion criteria were: baseline minor/major depression, excessive alcohol consumption and other causes for ALT elevation. Depression was evaluated by the eight-item Patient Health Questionnaire (PHQ-8) score. The final cohort included 5984 subjects [69.4% men, aged 45.0 (s.d. = 10.24) years]. The incidence rate of minor and major depression was 3.8% and 1.4%, respectively. Elevated ALT was a significant independent predictor for the occurrence of minor [odds ratio (OR) 2.02, 95% confidence interval (CI) 1.40-2.92] and major (OR 3.132, 95% CI 1.81-5.40) depression after adjusting for age, gender, body mass index, education level, serum levels of lipids, glucose, smoking and physical activity. Adding subjective health and affective state parameters (sleep disturbances, self-rated health, anxiety and burnout) as potential mediators only slightly ameliorated the association. Persistently elevated ALT was associated with the greatest risk for minor or major depression as compared with elevation only at baseline or follow-up (p for trend depressive symptoms, thus suggesting that NAFLD may represent an independent modifiable risk factor for depression.

  6. Branched-Chain Aminotransferases Control TORC1 Signaling in Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Joanne M Kingsbury

    2015-12-01

    Full Text Available The conserved target of rapamycin complex 1 (TORC1 integrates nutrient signals to orchestrate cell growth and proliferation. Leucine availability is conveyed to control TORC1 activity via the leu-tRNA synthetase/EGOC-GTPase module in yeast and mammals, but the mechanisms sensing leucine remain only partially understood. We show here that both leucine and its α-ketoacid metabolite, α-ketoisocaproate, effectively activate the yeast TORC1 kinase via both EGOC GTPase-dependent and -independent mechanisms. Leucine and α-ketoisocaproate are interconverted by ubiquitous branched-chain aminotransferases (BCAT, which in yeast are represented by the mitochondrial and cytosolic enzymes Bat1 and Bat2, respectively. BCAT yeast mutants exhibit severely compromised TORC1 activity, which is partially restored by expression of Bat1 active site mutants, implicating both catalytic and structural roles of BCATs in TORC1 control. We find that Bat1 interacts with branched-chain amino acid metabolic enzymes and, in a leucine-dependent fashion, with the tricarboxylic acid (TCA-cycle enzyme aconitase. BCAT mutation perturbed TCA-cycle intermediate levels, consistent with a TCA-cycle block, and resulted in low ATP levels, activation of AMPK, and TORC1 inhibition. We propose the biosynthetic capacity of BCAT and its role in forming multicomplex metabolons connecting branched-chain amino acids and TCA-cycle metabolism governs TCA-cycle flux to activate TORC1 signaling. Because mammalian mitochondrial BCAT is known to form a supramolecular branched-chain α-keto acid dehydrogenase enzyme complex that links leucine metabolism to the TCA-cycle, these findings establish a precedent for understanding TORC1 signaling in mammals.

  7. L,L-diaminopimelate aminotransferase from Chlamydomonas reinhardtii: a target for algaecide development.

    Science.gov (United States)

    Dobson, Renwick C J; Girón, Irma; Hudson, André O

    2011-01-01

    In some bacterial species and photosynthetic cohorts, including algae, the enzyme L,L-diaminopimelate aminotransferase (DapL) (E.C. 2.6.1.83) is involved in the anabolism of the essential amino acid L-lysine. DapL catalyzes the conversion of tetrahydrodipicolinate (THDPA) to L,L-diaminopimelate (L,L-DAP), in one step bypassing the DapD, DapC and DapE enzymatic reactions present in the acyl DAP pathways. Here we present an in vivo and in vitro characterization of the DapL ortholog from the alga Chlamydomonas reinhardtii (Cr-DapL). The in vivo analysis illustrated that the enzyme is able to functionally complement the E. coli dap auxotrophs and was essential for plant development in Arabidopsis. In vitro, the enzyme was able to inter-convert THDPA and L,L-DAP, showing strong substrate specificity. Cr-DapL was dimeric in both solution and when crystallized. The structure of Cr-DapL was solved in its apo form, showing an overall architecture of a α/β protein with each monomer in the dimer adopting a pyridoxal phosphate-dependent transferase-like fold in a V-shaped conformation. The active site comprises residues from both monomers in the dimer and shows some rearrangement when compared to the apo-DapL structure from Arabidopsis. Since animals do not possess the enzymatic machinery necessary for the de novo synthesis of the amino acid L-lysine, enzymes involved in this pathway are attractive targets for the development of antibiotics, herbicides and algaecides.

  8. L,L-diaminopimelate aminotransferase from Chlamydomonas reinhardtii: a target for algaecide development.

    Directory of Open Access Journals (Sweden)

    Renwick C J Dobson

    Full Text Available In some bacterial species and photosynthetic cohorts, including algae, the enzyme L,L-diaminopimelate aminotransferase (DapL (E.C. 2.6.1.83 is involved in the anabolism of the essential amino acid L-lysine. DapL catalyzes the conversion of tetrahydrodipicolinate (THDPA to L,L-diaminopimelate (L,L-DAP, in one step bypassing the DapD, DapC and DapE enzymatic reactions present in the acyl DAP pathways. Here we present an in vivo and in vitro characterization of the DapL ortholog from the alga Chlamydomonas reinhardtii (Cr-DapL. The in vivo analysis illustrated that the enzyme is able to functionally complement the E. coli dap auxotrophs and was essential for plant development in Arabidopsis. In vitro, the enzyme was able to inter-convert THDPA and L,L-DAP, showing strong substrate specificity. Cr-DapL was dimeric in both solution and when crystallized. The structure of Cr-DapL was solved in its apo form, showing an overall architecture of a α/β protein with each monomer in the dimer adopting a pyridoxal phosphate-dependent transferase-like fold in a V-shaped conformation. The active site comprises residues from both monomers in the dimer and shows some rearrangement when compared to the apo-DapL structure from Arabidopsis. Since animals do not possess the enzymatic machinery necessary for the de novo synthesis of the amino acid L-lysine, enzymes involved in this pathway are attractive targets for the development of antibiotics, herbicides and algaecides.

  9. Relaxed evolution in the tyrosine aminotransferase gene tat in old world fruit bats (Chiroptera: Pteropodidae.

    Directory of Open Access Journals (Sweden)

    Bin Shen

    Full Text Available Frugivorous and nectarivorous bats fuel their metabolism mostly by using carbohydrates and allocate the restricted amounts of ingested proteins mainly for anabolic protein syntheses rather than for catabolic energy production. Thus, it is possible that genes involved in protein (amino acid catabolism may have undergone relaxed evolution in these fruit- and nectar-eating bats. The tyrosine aminotransferase (TAT, encoded by the Tat gene is the rate-limiting enzyme in the tyrosine catabolic pathway. To test whether the Tat gene has undergone relaxed evolution in the fruit- and nectar-eating bats, we obtained the Tat coding region from 20 bat species including four Old World fruit bats (Pteropodidae and two New World fruit bats (Phyllostomidae. Phylogenetic reconstructions revealed a gene tree in which all echolocating bats (including the New World fruit bats formed a monophyletic group. The phylogenetic conflict appears to stem from accelerated TAT protein sequence evolution in the Old World fruit bats. Our molecular evolutionary analyses confirmed a change in the selection pressure acting on Tat, which was likely caused by a relaxation of the evolutionary constraints on the Tat gene in the Old World fruit bats. Hepatic TAT activity assays showed that TAT activities in species of the Old World fruit bats are significantly lower than those of insectivorous bats and omnivorous mice, which was not caused by a change in TAT protein levels in the liver. Our study provides unambiguous evidence that the Tat gene has undergone relaxed evolution in the Old World fruit bats in response to changes in their metabolism due to the evolution of their special diet.

  10. Allele-specific characterization of alanine: glyoxylate aminotransferase variants associated with primary hyperoxaluria.

    Directory of Open Access Journals (Sweden)

    Melissa D Lage

    Full Text Available Primary Hyperoxaluria Type 1 (PH1 is a rare autosomal recessive kidney stone disease caused by deficiency of the peroxisomal enzyme alanine: glyoxylate aminotransferase (AGT, which is involved in glyoxylate detoxification. Over 75 different missense mutations in AGT have been found associated with PH1. While some of the mutations have been found to affect enzyme activity, stability, and/or localization, approximately half of these mutations are completely uncharacterized. In this study, we sought to systematically characterize AGT missense mutations associated with PH1. To facilitate analysis, we used two high-throughput yeast-based assays: one that assesses AGT specific activity, and one that assesses protein stability. Approximately 30% of PH1-associated missense mutations are found in conjunction with a minor allele polymorphic variant, which can interact to elicit complex effects on protein stability and trafficking. To better understand this allele interaction, we functionally characterized each of 34 mutants on both the major (wild-type and minor allele backgrounds, identifying mutations that synergize with the minor allele. We classify these mutants into four distinct categories depending on activity/stability results in the different alleles. Twelve mutants were found to display reduced activity in combination with the minor allele, compared with the major allele background. When mapped on the AGT dimer structure, these mutants reveal localized regions of the protein that appear particularly sensitive to interactions with the minor allele variant. While the majority of the deleterious effects on activity in the minor allele can be attributed to synergistic interaction affecting protein stability, we identify one mutation, E274D, that appears to specifically affect activity when in combination with the minor allele.

  11. Tyrosine Aminotransferase Contributes to Benzylisoquinoline Alkaloid Biosynthesis in Opium Poppy1[W

    Science.gov (United States)

    Lee, Eun-Jeong; Facchini, Peter J.

    2011-01-01

    Tyrosine aminotransferase (TyrAT) catalyzes the transamination of l-Tyr and α-ketoglutarate, yielding 4-hydroxyphenylpyruvic acid and l-glutamate. The decarboxylation product of 4-hydroxyphenylpyruvic acid, 4-hydroxyphenylacetaldehyde, is a precursor to a large and diverse group of natural products known collectively as benzylisoquinoline alkaloids (BIAs). We have isolated and characterized a TyrAT cDNA from opium poppy (Papaver somniferum), which remains the only commercial source for several pharmaceutical BIAs, including codeine, morphine, and noscapine. TyrAT belongs to group I pyridoxal 5′-phosphate (PLP)-dependent enzymes wherein Schiff base formation occurs between PLP and a specific Lys residue. The amino acid sequence of TyrAT showed considerable homology to other putative plant TyrATs, although few of these have been functionally characterized. Purified, recombinant TyrAT displayed a molecular mass of approximately 46 kD and a substrate preference for l-Tyr and α-ketoglutarate, with apparent Km values of 1.82 and 0.35 mm, respectively. No specific requirement for PLP was detected in vitro. Liquid chromatography-tandem mass spectrometry confirmed the conversion of l-Tyr to 4-hydroxyphenylpyruvate. TyrAT gene transcripts were most abundant in roots and stems of mature opium poppy plants. Virus-induced gene silencing was used to evaluate the contribution of TyrAT to BIA metabolism in opium poppy. TyrAT transcript levels were reduced by at least 80% in silenced plants compared with controls and showed a moderate reduction in total alkaloid content. The modest correlation between transcript levels and BIA accumulation in opium poppy supports a role for TyrAT in the generation of alkaloid precursors, but it also suggests the occurrence of other sources for 4-hydroxyphenylacetaldehyde. PMID:21949209

  12. Association between Serum Uric Acid and Elevated Alanine Aminotransferase in the General Population.

    Science.gov (United States)

    Chen, Shuang; Guo, Xiaofan; Yu, Shasha; Sun, Guozhe; Yang, Hongmei; Li, Zhao; Sun, Yingxian

    2016-08-24

    Both the serum uric acid (SUA) level and elevated alanine aminotransferase (ALT) are related to metabolic syndrome. However, the association between SUA and elevated ALT has not been elucidated in the general population. The objective of this study was to investigate the association between SUA and elevated ALT in the general population of China; A total of 11,572 adults (≥35 years of age) participated in this survey. Elevated ALT was defined as >40 U/L. SUA ≥ 7.0 mg/dL in males or ≥6.0 mg/dL in females was defined as hyperuricemia. SUA within the reference range was divided into quartiles, and its associations with elevated ALT were evaluated by logistic regressions; A total of 7.4% participants had elevated ALT. The prevalence of hyperuricemia was 14.9% in males and 7.3% in females. There was a significantly positive dose-response association between SUA levels and the prevalence of elevated ALT. After adjusting for potential confounders, a positive relationship for elevated ALT was observed in subjects with hyperuricemia (odds ratio [OR]: 2.032, 95% confidence interval [CI]: 1.443-2.861 for men; OR: 2.045, 95% CI: 1.221-3.425 for women, both p < 0.05). Within the reference range, the association between SUA and elevated ALT persisted in the fourth quartile (OR: 1.467, 95% CI: 1.063-2.025 for men; OR: 1.721, 95% CI: 1.146-2.585 for women, both p < 0.05); Our results indicated that an increased SUA level, even within the reference range, was independently associated with elevated ALT in Chinese adults.

  13. Hb and dyslipidaemia as predicting markers of serum alanine aminotransferase elevation in Chinese adolescents.

    Science.gov (United States)

    Chao, Kuo-Ching; Chang, Chun-Chao; Owaga, Eddy; Bai, Chyi-Huey; Huang, Tzu-chieh; Pan, Wen-Harn; Chang, Jung-Su

    2016-04-01

    Fe is an essential element for erythropoiesis and Hb synthesis. High Hb levels affect the blood's viscosity and are associated with cardiovascular dysfunction. The aim of the present study was to examine relationships of Hb and cardiometabolic abnormalities with the risk of alanine aminotransferase (ALT) elevation in adolescents. A population-based, cross-sectional study. National Nutrition and Health Survey in Taiwan (2010-2011, adolescents). Healthy adolescents aged 13-18 years. In total, 1941 adolescents (963 boys and 978 girls) were entered in the study. The mean age was 15·3 (sd 0·1) years (boys, 15·3 (sd 0·1) years; girls, 15·2 (sd 0·1) years). ALT tertile cut-off points for boys were 11 and 16 U/l, and for girls were 9 and 12 U/l. Girls without dyslipidaemia and presenting in the highest quartile (Q1) of Hb (>13·6 g/dl) were 1·89 and 3·76 times more likely to have raised serum ALT (9 and >12 U/l, respectively) than the reference (lowest quartile of Hb (Q1), 12 U/l) than the reference (Q1 of Hb, 15·4 g/dl), who were 7·40 times more likely to have elevated serum ALT of >16 U/l than the reference (Q1 of Hb, Hb level is a predictor of elevated serum ALT in adolescent girls with dyslipidaemia. Our study also highlights the importance of further research to establish cut-off points for Hb and its utility in diagnosing and preventing the onset of dyslipidaemia in adolescents.

  14. 4-aminobutyrate aminotransferase (ABAT: genetic and pharmacological evidence for an involvement in gastro esophageal reflux disease.

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    Johan Jirholt

    Full Text Available Gastro-esophageal reflux disease (GERD is partly caused by genetic factors. The underlying susceptibility genes are currently unknown, with the exception of COL3A1. We used three independent GERD patient cohorts to identify GERD susceptibility genes. Thirty-six families, demonstrating dominant transmission of GERD were subjected to whole genome microsatellite genotyping and linkage analysis. Five linked regions were identified. Two families shared a linked region (LOD 3.9 and 2.0 on chromosome 16. We used two additional independent GERD patient cohorts, one consisting of 219 trios (affected child with parents and the other an adult GERD case control cohort consisting of 256 cases and 485 controls, to validate individual genes in the linked region through association analysis. Sixty six single nucleotide polymorphism (SNP markers distributed over the nine genes present in the linked region were genotyped in the independent GERD trio cohort. Transmission disequilibrium test analysis followed by multiple testing adjustments revealed a significant genetic association for one SNP located in an intron of the gene 4-aminobutyrate aminotransferase (ABAT (P(adj = 0.027. This association did not replicate in the adult case-control cohort, possibly due to the differences in ethnicity between the cohorts. Finally, using the selective ABAT inhibitor vigabatrin (γ-vinyl GABA in a dog study, we were able to show a reduction of transient lower esophageal sphincter relaxations (TLESRs by 57.3 ± 11.4 % (p = 0.007 and the reflux events from 3.1 ± 0.4 to 0.8 ± 0.4 (p = 0.007. Our results demonstrate the direct involvement of ABAT in pathways affecting lower esophageal sphincter (LES control and identifies ABAT as a genetic risk factor for GERD.

  15. 4-aminobutyrate aminotransferase (ABAT): genetic and pharmacological evidence for an involvement in gastro esophageal reflux disease.

    Science.gov (United States)

    Jirholt, Johan; Asling, Bengt; Hammond, Paul; Davidson, Geoffrey; Knutsson, Mikael; Walentinsson, Anna; Jensen, Jörgen M; Lehmann, Anders; Agreus, Lars; Lagerström-Fermer, Maria

    2011-04-28

    Gastro-esophageal reflux disease (GERD) is partly caused by genetic factors. The underlying susceptibility genes are currently unknown, with the exception of COL3A1. We used three independent GERD patient cohorts to identify GERD susceptibility genes. Thirty-six families, demonstrating dominant transmission of GERD were subjected to whole genome microsatellite genotyping and linkage analysis. Five linked regions were identified. Two families shared a linked region (LOD 3.9 and 2.0) on chromosome 16. We used two additional independent GERD patient cohorts, one consisting of 219 trios (affected child with parents) and the other an adult GERD case control cohort consisting of 256 cases and 485 controls, to validate individual genes in the linked region through association analysis. Sixty six single nucleotide polymorphism (SNP) markers distributed over the nine genes present in the linked region were genotyped in the independent GERD trio cohort. Transmission disequilibrium test analysis followed by multiple testing adjustments revealed a significant genetic association for one SNP located in an intron of the gene 4-aminobutyrate aminotransferase (ABAT) (P(adj) = 0.027). This association did not replicate in the adult case-control cohort, possibly due to the differences in ethnicity between the cohorts. Finally, using the selective ABAT inhibitor vigabatrin (γ-vinyl GABA) in a dog study, we were able to show a reduction of transient lower esophageal sphincter relaxations (TLESRs) by 57.3 ± 11.4 % (p = 0.007) and the reflux events from 3.1 ± 0.4 to 0.8 ± 0.4 (p = 0.007). Our results demonstrate the direct involvement of ABAT in pathways affecting lower esophageal sphincter (LES) control and identifies ABAT as a genetic risk factor for GERD.

  16. First molecular modeling report on novel arylpyrimidine kynurenine monooxygenase inhibitors through multi-QSAR analysis against Huntington's disease: A proposal to chemists!

    Science.gov (United States)

    Amin, Sk Abdul; Adhikari, Nilanjan; Jha, Tarun; Gayen, Shovanlal

    2016-12-01

    Huntington's disease (HD) is caused by mutation of huntingtin protein (mHtt) leading to neuronal cell death. The mHtt induced toxicity can be rescued by inhibiting the kynurenine monooxygenase (KMO) enzyme. Therefore, KMO is a promising drug target to address the neurodegenerative disorders such as Huntington's diseases. Fiftysix arylpyrimidine KMO inhibitors are structurally explored through regression and classification based multi-QSAR modeling, pharmacophore mapping and molecular docking approaches. Moreover, ten new compounds are proposed and validated through the modeling that may be effective in accelerating Huntington's disease drug discovery efforts. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. High Prevalence of Nonalcoholic Fatty Liver Disease in Patients With Type 2 Diabetes Mellitus and Normal Plasma Aminotransferase Levels.

    Science.gov (United States)

    Portillo-Sanchez, Paola; Bril, Fernando; Maximos, Maryann; Lomonaco, Romina; Biernacki, Diane; Orsak, Beverly; Subbarayan, Sreevidya; Webb, Amy; Hecht, Joan; Cusi, Kenneth

    2015-06-01

    Nonalcoholic fatty liver disease (NAFLD) and its more severe form with steatohepatitis (NASH) are common in patients with type 2 diabetes mellitus (T2DM). However, they are usually believed to largely affect those with elevated aminotransferases. The aim of this study was to determine the prevalence of NAFLD by the gold standard, liver magnetic resonance spectroscopy ((1)H-MRS) in patients with T2DM and normal aminotransferases, and to characterize their metabolic profile. We recruited 103 patients with T2DM and normal plasma aminotransferases (age, 60 ± 8 y; body mass index [BMI], 33 ± 5 kg/m(2); glycated hemoglobin [A1c], 7.6 ± 1.3%). We measured the following: 1) liver triglyceride content by (1)H-MRS; 2) systemic insulin sensitivity (homeostasis model assessment-insulin resistance); and 3) adipose tissue insulin resistance, both fasting (as the adipose tissue insulin resistance index: fasting plasma free fatty acids [FFA] × insulin) and during an oral glucose tolerance test (as the suppression of FFA). The prevalence of NAFLD and NASH were much higher than expected (50% and 56% of NAFLD patients, respectively). The prevalence of NAFLD was higher in obese compared with nonobese patients as well as with increasing BMI (P = .001 for trend). Higher plasma A1c was associated with a greater prevalence of NAFLD and worse liver triglyceride accumulation (P = .01). Compared with nonobese patients without NAFLD, patients with NAFLD had severe systemic (liver/muscle) and, particularly, adipose tissue (fasting/postprandial) insulin resistance (all P < .01). The prevalence of NAFLD is much higher than previously believed in overweight/obese patients with T2DM and normal aminotransferases. Moreover, many are at increased risk of NASH. Physicians should have a lower threshold for screening patients with T2DM for NAFLD/NASH.

  18. The Association of Elevated Serum Alanine Aminotransferase with Metabolic Syndrome in A Military Population in Southern Iran

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    B Sabayan

    2010-06-01

    Full Text Available Background: Metabolic syndrome (MetS is rapidly rising at an alarming rate through all parts of the world. Elevated serum aminotransferase was proposed as a marker for early detection of MetS. In this investigation we primarily aimed to evaluate the prevalence of MetS and its components among army and secondly to explore the association between elevated serum aminotransferase and the components of metabolic syndrome. Methods: A total of 380 army personnel from a military camp in Southern Iran participated in this cross-sectional study. Life style related characteristics, anthropometric features, serum aminotransferase and components of MetS, based on National Cholesterol Education Program—Adult Treatment Panel III, were measured. Statistical significant was set as p value less than 0.05. Results: The mean age of participants was 35.0± 7.5 year-old and the prevalence of metabolic syndrome was 8.1%. The prevalence of the components of MetS including; central obesity, abnormal fasting blood glucose, hypertension, hypertriglycridemia and low HDL cholesterol level was 8.6%, 10.4%, 18.5%, 31%, and 45.5% respectively. MetS had significant relationship with obesity (P<0.001 and abnormal Waist Circumferance/Hip Circumference ratio (P<0.001. Twenty-six percent of subjects had ALT ≥ 41 U/L and 4.9% of them had ALT ≥ 81. Elevated serum aminotransferase had significant association with presence of MetS (P= 0.007. Conclusion: Although prevalence of metabolic syndrome among the studied army population was not high, life style modification of army members is recommended. Liver function tests should be included in routine health checkup of military personnel.

  19. Effects of Nordic Walking and Pilates training programs on aminotransferase activity in overweight and obese elderly women

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    Magdalena Hagner-Derengowska

    2015-12-01

    3 Chair of Vascular and Internal Diseases, Faculty of Health Sciences, Nicolaus Copernicus University in Toruń, Poland     Corresponding author: Magdalena Hagner-Derengowska, PT, PhD Chair of Clinical Neuropsychology, Nicolaus Copernicus University in Toruń M. Skłodowskiej-Curie 9 Street, 85-094 Bydgoszcz, Poland E-mail address: m_hagner-derengowska@wp.pl     ABSTRACT Background & Aims: Elevation of alanine (ALT and aspartate aminotransferase (AST activities may appear as liver injury due to fat storage and other enzyme sources, such as rhabdomyolysis. Elevated ALT is associated with all-cause and cardiovascular mortality in an elderly population. The aims of this study was to determine the effect of a 10-weeks training program on the serum activity of these enzymes in postmenopausal women with overweight and obesity. Methods: The study comprised 81 postmenopausal women with overweight and obesity: 34 (42% of whom completed a 10-weeks Nordic Walking (NW rehabilitation program, 27 (33% of whom completed a Pilates rehabilitation program, and 20 (25% of whom were the control group. Blood for testing for ALT, AST, and other parameters of metabolic syndrome was collected before the program commenced and after it finished. Results: Elevated (> 34 U/l ALT and AST activities presented in 9 (11% and 7 (9% of the patients, respectively. A reduction in ALT and AST activities was observed in 43 (53% of the subjects, and in 61%, 59% and 40%, and 47%, 63% and 50% of the individuals who completed the NW and Pilates programs and were in the control group, respectively. Conclusions: The outcome of the training programs on aminotransferase serum activities in postmenopausal women with overweight and obesity was individually different and not related to exercise type.   Keywords: alanine aminotransferase, aspartate aminotransferase, obesity, Nordic Walking, Pilates.

  20. Effect of streptococcal preparation (picibanil) on the postoperative rise in serum alanine aminotransferase activity in patients with urogenital cancer.

    OpenAIRE

    Taketa, Kazuhisa; Ohmori, Hiroyuki; Matsumura, Yonesuke; Asahi, Toshihiko; Okimune, Masaaki

    1980-01-01

    The effect of Picibanil, a streptococcal agent, on the development of liver injury after operations for urogenital cancer was studied retrospectively in the light of serum alanine aminotransferase (ALT) activity. The series comprised 32 cases receiving Picibanil and 33 controls with otherwise comparable clinical backgrounds. Picibanil reduced the incidence of postoperative ALT rise over 50 U/l within 6 weeks but increased it thereafter. The increase in ALT activity after 6 weeks was relativel...

  1. Accuracy of the paracetamol-aminotransferase product to predict hepatotoxicity in paracetamol overdose treated with a 2-bag acetylcysteine regimen.

    Science.gov (United States)

    Wong, Anselm; Sivilotti, Marco L A; Gunja, Naren; McNulty, Richard; Graudins, Andis

    2018-03-01

    Paracetamol concentration is a highly accurate risk predictor for hepatotoxicity following overdose with known time of ingestion. However, the paracetamol-aminotransferase multiplication product can be used as a risk predictor independent of timing or ingestion type. Validated in patients treated with the traditional, "three-bag" intravenous acetylcysteine regimen, we evaluated the accuracy of the multiplication product in paracetamol overdose treated with a two-bag acetylcysteine regimen. We examined consecutive patients treated with the two-bag regimen from five emergency departments over a two-year period. We assessed the predictive accuracy of initial multiplication product for the primary outcome of hepatotoxicity (peak alanine aminotransferase ≥1000IU/L), as well as for acute liver injury (ALI), defined peak alanine aminotransferase ≥2× baseline and above 50IU/L). Of 447 paracetamol overdoses treated with the two-bag acetylcysteine regimen, 32 (7%) developed hepatotoxicity and 73 (16%) ALI. The pre-specified cut-off points of 1500 mg/L × IU/L (sensitivity 100% [95% CI 82%, 100%], specificity 62% [56%, 67%]) and 10,000 mg/L × IU/L (sensitivity 70% [47%, 87%], specificity of 97% [95%, 99%]) were highly accurate for predicting hepatotoxicity. There were few cases of hepatotoxicity irrespective of the product when acetylcysteine was administered within eight hours of overdose, when the product was largely determined by a high paracetamol concentration but normal aminotransferase. The multiplication product accurately predicts hepatotoxicity when using a two-bag acetylcysteine regimen, especially in patients treated more than eight hours post-overdose. Further studies are needed to assess the product as a method to adjust for exposure severity when testing efficacy of modified acetylcysteine regimens.

  2. Comparison of blood aminotransferase methods for assessment of myopathy and hepatopathy in Florida manatees (Trichechus manatus latirostris).

    Science.gov (United States)

    Harr, Kendal E; Allison, Kathryn; Bonde, Robert K; Murphy, David; Harvey, John W

    2008-06-01

    Muscle injury is common in Florida manatees (Trichechus manatus latirostris). Plasma aspartate aminotransferase (AST) is frequently used to assess muscular damage in capture myopathy and traumatic injury. Therefore, accurate measurement of AST and alanine aminotransferase (ALT) is important in managed, free-ranging animals, as well as in those rehabilitating from injury. Activities of these enzymes, however, are usually not increased in manatees with either acute or chronic muscle damage, despite marked increases in plasma creatine kinase activity. It is hypothesized that this absence of response is due to apoenzymes in the blood not detected by commonly used veterinary assays. Addition of coenzyme pyridoxal-5-phosphate (P5P or vitamin B6) should, therefore, result in higher measured enzyme activities. The objective of this study was to determine the most accurate, precise, and diagnostically useful method for aminotransferase measurement in manatees that can be used in veterinary practices and diagnostic laboratories. Additionally, appropriate collection and storage techniques were assessed. The use of an optimized commercial wet chemical assay with 100 micromol P5P resulted in a positive bias of measured enzyme activities in a healthy population of animals. However, AST and ALT were still much lower than that typically observed in domestic animals and should not be used alone in the assessment of capture myopathy and muscular trauma. Additionally, the dry chemistry analyzer, typically used in clinics, reported significantly higher and less precise AST and ALT activities with poor correlation to those measured with wet chemical methods found in diagnostic laboratories. Therefore, these results cannot be clinically compared. Overall, the optimized wet chemical method was the most precise and diagnostically useful measurement of aminotransferase in samples. Additionally, there was a statistically significant difference between paired serum and plasma measurement

  3. Activity of aminotransferases in organs of rats during hypoxia of enclosed space of the action of thiamine bromide

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    Сніжана Сергіївна Чернадчук

    2015-05-01

    Full Text Available It is studied an aminotransferase activity during injection of thiamin bromide in rat tissues in normal and hypoxic enclosed space. After injection of thiamine bromide we have set reduction of AST and ALT activity, relative to control, except by the brain tissue, where there was an increase of investigated indicators. The decrease of activity of the investigated elements is occurred in animals which before hypoxia were injection of thiamine bromide

  4. Effect of Phenanthrene on the Tissue Structure of Liver and Aminotransferase Enzymes in Yellowfin Seabream (Acanthopagrus latus

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    Mehrnaz Shirmohammadi*

    2017-06-01

    Full Text Available Background: Polycyclic aromatic hydrocarbons (PAHs such as phenanthrene (Phe represent one of the most abundant forms of organic pollutants. The aim of this study was to assess changes in plasma levels of aminotransferase enzymes, total protein and liver tissue as biomarkers of yellowfin seabream (Acanthopagrus latus exposed to Phe for 14 d. Methods: The research was carried out in January 2016 at Khorramshahr University of Marine Sciences and Technology, Khorramshahr, Iran. Some 72 fish were injected with 2, 20, 40 and 70 mg/kg of Phe. Then tissue and blood samples were obtained at 1, 4, 7 and 14 d after injection. Results: Exposure of fish to Phe resulted in a significant increase of alanine aminotransferase (ALT, aspartate aminotransferase (AST and decrease of total protein after 7 d of the experiment (P<0.05. The main histopathological alteration was showed in different sampling days including nucleus margination, hypertrophy, vacuolation, melanomacrophages aggregates, sinusoid dilation, degeneration and picnotic nucleus. Degree of tissue change (DTC of liver was recorded in the Phe-exposed fish from normal range to moderate changes. Conclusion: The studied biomarkers such as changes in concentrations of ALT, AST and total protein as well as tissue damages in liver may be served as beneficial biomarker to assess Phe toxicity in yellowfin seabream.

  5. The Kynurenine 3-Monooxygenase Encoding Gene, BcKMO, Is Involved in the Growth, Development, and Pathogenicity of Botrytis cinerea

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    Kang Zhang

    2018-05-01

    Full Text Available A pathogenic mutant, BCG183, was obtained by screening the T-DNA insertion library of Botrytis cinerea. A novel pathogenicity-related gene BcKMO, which encodes kynurenine 3-monooxygenase (KMO, was isolated and identified via thermal asymmetric interlaced PCR, bioinformatics analyses, and KMO activity measurement. The mutant BCG183 grew slowly, did not produce conidia and sclerotia, had slender hyphae, and presented enhanced pathogenicity. The phenotype and pathogenicity of the BcKMO-complementing mutant (BCG183/BcKMO were similar to those of the wild-type (WT strain. The activities of polymethylgalacturonase, polygalacturonase, and toxins were significantly higher, whereas acid production was significantly decreased in the mutant BCG183, when compared with those in the WT and BCG183/BcKMO. Moreover, the sensitivity of mutant BCG183 to NaCl and KCl was remarkably increased, whereas that to fluconazole, Congo Red, menadione, H2O2, and SQ22536 and U0126 [cAMP-dependent protein kinase (cAMP and mitogen-activated protein kinase (MAPK signaling pathways inhibitors, respectively] were significantly decreased compared with the other strains. Furthermore, the key genes involved in the cAMP and MAPK signaling pathways, Pka1, Pka2, PkaR, Bcg2, Bcg3, bmp1, and bmp3, were significantly upregulated or downregulated in the mutant BCG183. BcKMO expression levels were also upregulated or downregulated in the RNAi mutants of the key genes involved in the cAMP and MAPK signaling pathways. These findings indicated that BcKMO positively regulates growth and development, but negatively regulates pathogenicity of B. cinerea. Furthermore, BcKMO was found to be involved in controlling cell wall degrading enzymes activity, toxins activity, acid production, and cell wall integrity, and participate in cAMP and MAPK signaling pathways of B. cinerea.

  6. The Kynurenine 3-Monooxygenase Encoding Gene, BcKMO, Is Involved in the Growth, Development, and Pathogenicity of Botrytis cinerea.

    Science.gov (United States)

    Zhang, Kang; Yuan, Xuemei; Zang, Jinping; Wang, Min; Zhao, Fuxin; Li, Peifen; Cao, Hongzhe; Han, Jianmin; Xing, Jihong; Dong, Jingao

    2018-01-01

    A pathogenic mutant, BCG183, was obtained by screening the T-DNA insertion library of Botrytis cinerea . A novel pathogenicity-related gene BcKMO , which encodes kynurenine 3-monooxygenase (KMO), was isolated and identified via thermal asymmetric interlaced PCR, bioinformatics analyses, and KMO activity measurement. The mutant BCG183 grew slowly, did not produce conidia and sclerotia, had slender hyphae, and presented enhanced pathogenicity. The phenotype and pathogenicity of the BcKMO -complementing mutant (BCG183/ BcKMO ) were similar to those of the wild-type (WT) strain. The activities of polymethylgalacturonase, polygalacturonase, and toxins were significantly higher, whereas acid production was significantly decreased in the mutant BCG183, when compared with those in the WT and BCG183/ BcKMO . Moreover, the sensitivity of mutant BCG183 to NaCl and KCl was remarkably increased, whereas that to fluconazole, Congo Red, menadione, H 2 O 2 , and SQ22536 and U0126 [cAMP-dependent protein kinase (cAMP) and mitogen-activated protein kinase (MAPK) signaling pathways inhibitors, respectively] were significantly decreased compared with the other strains. Furthermore, the key genes involved in the cAMP and MAPK signaling pathways, Pka1 , Pka2 , PkaR , Bcg2 , Bcg3 , bmp1 , and bmp3, were significantly upregulated or downregulated in the mutant BCG183. BcKMO expression levels were also upregulated or downregulated in the RNAi mutants of the key genes involved in the cAMP and MAPK signaling pathways. These findings indicated that BcKMO positively regulates growth and development, but negatively regulates pathogenicity of B. cinerea . Furthermore, BcKMO was found to be involved in controlling cell wall degrading enzymes activity, toxins activity, acid production, and cell wall integrity, and participate in cAMP and MAPK signaling pathways of B. cinerea .

  7. Dual role of the carboxyl-terminal region of pig liver L-kynurenine 3-monooxygenase: mitochondrial-targeting signal and enzymatic activity.

    Science.gov (United States)

    Hirai, Kumiko; Kuroyanagi, Hidehito; Tatebayashi, Yoshitaka; Hayashi, Yoshitaka; Hirabayashi-Takahashi, Kanako; Saito, Kuniaki; Haga, Seiich; Uemura, Tomihiko; Izumi, Susumu

    2010-12-01

    l-kynurenine 3-monooxygenase (KMO) is an NAD(P)H-dependent flavin monooxygenase that catalyses the hydroxylation of l-kynurenine to 3-hydroxykynurenine, and is localized as an oligomer in the mitochondrial outer membrane. In the human brain, KMO may play an important role in the formation of two neurotoxins, 3-hydroxykynurenine and quinolinic acid, both of which provoke severe neurodegenerative diseases. In mosquitos, it plays a role in the formation both of eye pigment and of an exflagellation-inducing factor (xanthurenic acid). Here, we present evidence that the C-terminal region of pig liver KMO plays a dual role. First, it is required for the enzymatic activity. Second, it functions as a mitochondrial targeting signal as seen in monoamine oxidase B (MAO B) or outer membrane cytochrome b(5). The first role was shown by the comparison of the enzymatic activity of two mutants (C-terminally FLAG-tagged KMO and carboxyl-terminal truncation form, KMOΔC50) with that of the wild-type enzyme expressed in COS-7 cells. The second role was demonstrated with fluorescence microscopy by the comparison of the intracellular localization of the wild-type, three carboxyl-terminal truncated forms (ΔC20, ΔC30 and ΔC50), C-terminally FLAG-tagged wild-type and a mutant KMO, where two arginine residues, Arg461-Arg462, were replaced with Ser residues.

  8. Fibrosis index based on four factors better predicts advanced fibrosis or cirrhosis than aspartate aminotransferase/platelet ratio index in chronic hepatitis C patients

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    Chia-Chi Wang

    2015-10-01

    Conclusion: FIB-4 could predict hepatic fibrosis in CHC patients. By adding two parameters (age and alanine aminotransferase, FIB-4 better predicts advanced fibrosis and cirrhosis than APRI in CHC patients.

  9. Early changes in GABA and dlutamine levels and aminotransferase activity in rat brain after total-body γ-irradiation with absolutely lethal doses

    International Nuclear Information System (INIS)

    Rozanov, V.A.; Karpovich, G.A.

    1985-01-01

    The contents of gaama-aminobutyric acid (GABA) and glutamate (GL) as well as GABA-aspartate- and alanine aminotransferase activities were measured in rat cerebellum, cerebral cortex and truncus cerebri 1, 3, 6, 24 and 48 hr following total-body γ-irradiation ( 60 Co) with a dose of 30 Gy. All the indices under study changed in a similar way in the cortex and truncus cerebri while in the cerebellum, GABA level increased and GABA-α-ketoglutarate aminotransfearse activity decreased 60 min after irradiation. The levels of GABA and GL in the cortex and truncus cerebri decreased immediately and increased 24 hr after irradiation. Activity of aminotransferases changed in a phase manner: changes in aspartate- and alanine aminotransferase activity were more pronounced than those of GABA-α-ketoglutarate aminotransferase activity and correlated with the glutamate level changes

  10. Embryo yolk sac membrane kynurenine formamidase of l-tryptophan to NAD+ pathway as a primary target for organophosphorus insecticides (OPI) in OPI-induced NAD-associated avian teratogenesis.

    Science.gov (United States)

    Seifert, Josef

    2017-10-01

    The objective of this study was to provide in ovo evidence for the proposed role of kynurenine formamidase of l-tryptophan to NAD + pathway in embryo yolk sac membranes as a primary target for organophosphorus insecticide (OPI) teratogens in OPI-induced NAD-associated avian teratogenesis. Slices prepared from yolk sac membranes or embryo livers of chicken eggs treated with the OPI dicrotophos and/or methyl parathion were incubated with l-tryptophan. Yolk sac membrane slices metabolized l-tryptophan in the pathway to NAD + before that function was established in livers. OPI interfered in ovo with the second step of l-tryptophan to NAD + biosynthesis by inhibiting kynurenine formamidase. Its inhibition due to the teratogen dicrotophos occurred in yolk sac membranes during the period of embryo highest susceptibility to OPI teratogens in contrast to delayed and lower inhibition caused by the nonteratogen methyl parathion. Both OPI affected liver kynurenine formamidase in a similar manner. The onsets of liver enzyme inhibition, however, were delayed by about two days and occurred at the time of the reduced embryo susceptibility to teratogens. The early disruption of l-tryptophan metabolism and higher inhibition of kynurenine formamidase in yolk sac membranes may be the factors that determine action of OPI as teratogens in chicken embryos. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Accuracy of the paracetamol-aminotransferase multiplication product to predict hepatotoxicity in modified-release paracetamol overdose.

    Science.gov (United States)

    Wong, Anselm; Sivilotti, Marco L A; Graudins, Andis

    2017-06-01

    The paracetamol-aminotransferase multiplication product (APAP × ALT) is a risk predictor of hepatotoxicity that is somewhat independent of time and type of ingestion. However, its accuracy following ingestion of modified-release formulations is not known, as the product has been derived and validated after immediate-release paracetamol overdoses. The aim of this retrospective cohort study was to evaluate the accuracy of the multiplication product to predict hepatotoxicity in a cohort of patients with modified-release paracetamol overdose. We assessed all patients with modified-release paracetamol overdose presenting to our hospital network from October 2009 to July 2016. Ingestion of a modified-release formulation was identified by patient self-report or retrieval of the original container. Hepatotoxicity was defined as peak alanine aminotransferase ≥1000 IU/L, and acute liver injury (ALI) as a doubling of baseline ALT to more than 50 IU/L. Of 1989 paracetamol overdose presentations, we identified 73 modified-release paracetamol exposures treated with acetylcysteine. Five patients developed hepatotoxicity, including one who received acetylcysteine within eight hours of an acute ingestion. No patient with an initial multiplication product paracetamol overdose treated with acetylcysteine, the paracetamol-aminotransferase multiplication product demonstrated similar accuracy and temporal profile to previous reports involving mostly immediate-release formulations. Above a cut-point of 10,000 mg/L × IU/L, it was very strongly associated with the development of acute liver injury and hepatotoxicity, especially when calculated more than eight hours post-ingestion. When below 1500 mg/L × IU/L the likelihood of developing hepatotoxicity was very low. Persistently high serial multiplication product calculations were associated with the greatest risk of hepatotoxicity.

  12. Correlation between Aminotransferase Ratio (AST/ALT and Other Biochemical Parameters in Chronic Liver Disease of Viral Origin

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    Shah Md Fazlul Karim

    2015-03-01

    Full Text Available Background: In recent years the ratio of aspartate aminotransferase (AST to alanine aminotransferase (ALT in patients of chronic liver disease (CLD of various origins has gained much attention. This variable is readily available, easy to interpret, and inexpensive and the clinical utility of the AST/ALT ratio in the diagnostic workup of patients with CLD is quite promising. Objective: The present study was designed to find out the link between aminotransferase (AST/ALT ratio with commonly measured biochemical parameters of liver function tests in CLD of viral origin. Materials and method: This cross sectional study was carried out in the department of Biochemistry, Sir Salimullah Medical College, Dhaka, Bangladesh. Forty four biopsy proven diagnosed subjects of chronic viral hepatitis without cirrhosis of both sex were selected purposively. With aseptic precaution 5 mL venous blood was collected from each subject and common liver function tests (serum AST, ALT, AST/ALT ratio, alkaline phosphatase, total bilirubin, serum total protein, serum albumin, serum globulin, serum albumin/globulin ratio, prothrombin time and viral serology (HBsAg, Anti HDV antibody, Anti HCV antibody were performed. Data were analyzed by SPSS version 19 for Windows. Pearson’s correlation test was done to determine association between AST/ALT with other biochemical parameters. Results: Mean(±SD age of the study subjects was 32.55±10.55 years (range 20-50 years with 48 (77.7% male and 14 (22.6% female subjects. Pearson’s correlation test was done between AST to ALT ratio with other biochemical parameters and prothrombin time showed significant positive correlation (p <0.01. Conclusion: In our study we found significant positive correlation between AST/ALT with prothrombin time in CLD subjects without cirrhosis.

  13. Does tryptophan degradation along the kynurenine pathway mediate the association between pro-inflammatory immune activity and depressive symptoms?

    Science.gov (United States)

    Quak, Jacqueline; Doornbos, Bennard; Roest, Annelieke M; Duivis, Hester E; Vogelzangs, Nicole; Nolen, Willem A; Penninx, Brenda W J H; Kema, Ido P; de Jonge, Peter

    2014-07-01

    Several studies have suggested that induced tryptophan (TRP) degradation through the kynurenine (KYN) pathway by the enzyme indoleamine 2,3-dioxygenase (IDO) is implicated in the relation between depression and inflammation. We investigated the role of tryptophan degradation in the relationship between inflammatory markers and depressive symptoms in the Netherlands Study of Depression and Anxiety (NESDA) and hypothesized that tryptophan degradation would mediate (part of) this association. 2812 Participants of NESDA were included in this study including 1042 persons with current major depressive disorder (MDD). Assessments of C-reactive protein (CRP), interleukin (IL)-6, tumor-necrosis factor (TNF)-α, KYN and TRP were obtained from fasting blood samples at the baseline assessment. Tryptophan degradation was estimated by calculating the ratio [KYN/TRP]. Depressive symptoms were measured with the Inventory of Depressive Symptomatology. Significant associations between inflammation and depressive symptoms were found for CRP and IL-6, for the total group and the subgroup of patients with current MDD. Adjustment for KYN/TRP did not attenuate these associations. There were no significant indirect effects for CRP on depressive symptoms mediated by KYN/TRP for the whole group (B=-0.032; 95% CI: -0.103 to 0.028) and for the subgroup of patients with current MDD (B=0.059; 95% CI: -0.037 to 0.165). Also IL-6 did not indirectly affect depressive symptoms through KYN/TRP in the total group (B=-0.023; 95% CI: -0.093 to 0.045) and in the MDD subgroup B=0.052; 95% CI: -0.019 to 0.144). Finally, no significant relation between depressive symptoms and KYN/TRP was found in the whole group (β=-0.019, p=0.311) nor in the subgroup with MDD (β=0.025, p=0.424). We did not find indications for tryptophan degradation, measured by KYN/TRP, to mediate the relationship between inflammation and depressive symptoms. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Purification and characterization of a branched-chain amino acid aminotransferase from Lactobacillus paracasei subsp paracasei CHCC 2115

    DEFF Research Database (Denmark)

    Thage, B.V.; Rattray, F.P.; Laustsen, M.W.

    2004-01-01

    Purification and characterization of an aminotransferase (AT) specific for the degradation of branched-chain amino acids from Lactobacillus paracasei subsp. paracasei CHCC 2115. Methods and Results: The purification protocol consisted of anion exchange chromatography, affinity chromatography...... of other metal ions, thiol- and carbonyl-binding agents. The N-terminal sequence of the enzyme was SVNIDWNNLGFDYMQLPYRYVAHXKDGVXD, and had at the amino acid level, 60 and 53% identity to a branched-chain amino acid AT of Lact. plantarum and Lactococcus lactis, respectively. Conclusions: The results suggest...

  15. Plasma Levels of Alanine Aminotransferase in the First Trimester Identify High Risk Chinese Women for Gestational Diabetes

    OpenAIRE

    Leng, Junhong; Zhang, Cuiping; Wang, Peng; Li, Nan; Li, Weiqin; Liu, Huikun; Zhang, Shuang; Hu, Gang; Yu, Zhijie; Ma, Ronald CW; Chan, Juliana CN; Yang, Xilin

    2016-01-01

    Alanine aminotransferase (ALT) predicts type 2 diabetes but it is uncertain whether it also predicts gestational diabetes mellitus (GDM). We recruited 17359 Chinese women with ALT measured in their first trimester. At 24?28?weeks of gestation, all women underwent a 50-gram 1-hour glucose challenge test (GCT) followed by a 75-gram 2-hour oral glucose tolerance test if GCT result was ?7.8?mmol/L. Restricted cubic spline analysis was used to examine full-range risk associations of ALT levels wit...

  16. Effects of Nordic Walking and Pilates training programs on aminotransferase activity in overweight and obese elderly women

    OpenAIRE

    Magdalena Hagner-Derengowska; Krystian Kałużny; Jacek Budzyński

    2015-01-01

    Hagner-Derengowska Magdalena, Kałużny Krystian, Budzyński Jacek. Effects of Nordic Walking and Pilates training programs on aminotransferase activity in overweight and obese elderly women. Journal of Education, Health and Sport. 2015;5(12):563-580. eISSN 2391-8306. DOIhttp://dx.doi.org/10.5281/zenodo.44249 http://ojs.ukw.edu.pl/index.php/johs/article/view/2015%3B5%2812%29%3A563-580 http://pbn.nauka.gov.pl/works/687148 Formerly Journal of Health Sciences. ISSN 1429-9623 / 2300-665X...

  17. Effects of Nordic Walking and Pilates training programs on aminotransferase activity in overweight and obese elderly women

    OpenAIRE

    Hagner-Derengowska, Magdalena; Kałużny, Krystian; Budzyński, Jacek

    2015-01-01

    Hagner-Derengowska Magdalena, Kałużny Krystian, Budzyński Jacek. Effects of Nordic Walking and Pilates training programs on aminotransferase activity in overweight and obese elderly women. Journal of Education, Health and Sport. 2015;5(12):563-580. eISSN 2391-8306. DOI http://dx.doi.org/10.5281/zenodo.44248 http://ojs.ukw.edu.pl/index.php/johs/article/view/2015%3B5%2812%29%3A563-580 http://pbn.nauka.gov.pl/works/687148 Formerly Journal of Health Sciences. ISSN 1429-9623 / 2300-665...

  18. Role of L-lysine-alpha-ketoglutarate aminotransferase in catabolism of lysine as a nitrogen source for Rhodotorula glutinis.

    Science.gov (United States)

    Kinzel, J J; Winston, M K; Bhattacharjee, J K

    1983-01-01

    Wild-type and saccharopine dehydrogenaseless mutant strains of Rhodotorula glutinis grew in minimal medium containing lysine as the sole nitrogen source and simultaneously accumulated, in the culture supernatant, large amounts of a product identified as alpha-aminoadipic-delta-semialdehyde. The saccharopine dehydrogenase and pipecolic acid oxidase levels remained unchanged in wild-type cells grown in the presence of ammonium or lysine as the nitrogen source. Lysine-alpha-ketoglutarate aminotransferase activity was demonstrated in ammonium-grown cells. This activity was depressed in cells grown in the presence of lysine as the sole source of nitrogen. PMID:6408065

  19. Effect of X-irradiation on the alanine- and aspartate aminotransferase activity in the liver, kidney and spleen of mice

    Energy Technology Data Exchange (ETDEWEB)

    Jungowska-Klin, B; Lozinska, M; Wojtaszek, J [Wroclaw Univ. (Poland)

    1975-01-01

    The alanine- and aspartate aminotransferase (GOT and GPT) activities and the protein content were measured in the liver, kidney and spleen homogenates of mice exposed to a single whole body X-irradiation with a 900 R dose. The assays were performed in 6 h intervals during the first day and 24 h intervals from the 2nd until the 6th day after the exposure. Significant differences in the enzymatic activity were found in the course of 24 h in control animals and a marked increase of this activity was found after irradiation. This may be explained by changes in the permeability of the mitochondrial membrane for enzyme molecules.

  20. Crystallization and preliminary X-ray diffraction analysis of l,l-diaminopimelate aminotransferase (DapL) from Chlamydomonas reinhardtii

    International Nuclear Information System (INIS)

    Hudson, André O.; Girón, Irma; Dobson, Renwick C. J.

    2010-01-01

    A variant of the diaminopimelate/lysine pathway has recently been defined following the discovery of the enzyme l,l-diaminopimelate aminotransferase (DapL). The cloning of the cDNA, recombinant expression, purification and preliminary diffraction analysis of DapL from the alga C. reinhardtii are presented. In the anabolic synthesis of diaminopimelate and lysine in plants and in some bacteria, the enzyme l,l-diaminopimelate aminotransferase (DapL; EC 2.6.1.83) catalyzes the conversion of tetrahydrodipicolinic acid (THDPA) to l,l-diaminopimelate, bypassing the DapD, DapC and DapE enzymatic steps in the bacterial acyl pathways. Here, the cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of DapL from the alga Chlamydomonas reinhardtii are presented. Protein crystals were grown in conditions containing 25%(w/v) PEG 3350 and 200 mM lithium sulfate and initially diffracted to ∼1.35 Å resolution. They belonged to space group P2 1 2 1 2 1 , with unit-cell parameters a = 58.9, b = 91.8, c = 162.9 Å. The data were processed to 1.55 Å resolution with an R merge of 0.081, an R p.i.m. of 0.044, an R r.i.m of 0.093 and a V M of 2.28 Å 3 Da −1

  1. An ll-Diaminopimelate Aminotransferase Defines a Novel Variant of the Lysine Biosynthesis Pathway in Plants1[W

    Science.gov (United States)

    Hudson, André O.; Singh, Bijay K.; Leustek, Thomas; Gilvarg, Charles

    2006-01-01

    Although lysine (Lys) biosynthesis in plants is known to occur by way of a pathway that utilizes diaminopimelic acid (DAP) as a central intermediate, the available evidence suggests that none of the known DAP-pathway variants found in nature occur in plants. A new Lys biosynthesis pathway has been identified in Arabidopsis (Arabidopsis thaliana) that utilizes a novel transaminase that specifically catalyzes the interconversion of tetrahydrodipicolinate and ll-diaminopimelate, a reaction requiring three enzymes in the DAP-pathway variant found in Escherichia coli. The ll-DAP aminotransferase encoded by locus At4g33680 was able to complement the dapD and dapE mutants of E. coli. This result, in conjunction with the kinetic properties and substrate specificity of the enzyme, indicated that ll-DAP aminotransferase functions in the Lys biosynthetic direction under in vivo conditions. Orthologs of At4g33680 were identified in all the cyanobacterial species whose genomes have been sequenced. The Synechocystis sp. ortholog encoded by locus sll0480 showed the same functional properties as At4g33680. These results demonstrate that the Lys biosynthesis pathway in plants and cyanobacteria is distinct from the pathways that have so far been defined in microorganisms. PMID:16361515

  2. Effect of heavy metals (Cu, Cd and Pb) on aspartate and alanine aminotransferase in Ruditapes philippinarum (Mollusca: Bivalvia)

    International Nuclear Information System (INIS)

    Blasco, J.; Puppo, J.

    1999-01-01

    The accumulation of cadmium, copper and lead and their effects on aspartate and alanine aminotransferases in digestive gland, gills, foot and soft body in the clam Ruditapes philippinarum were examined. The animals were exposed to different concentrations: Cd (200-600 μg·l -1 ), Pb (350-700 μg·l -1 ) and Cu (10-20 μg·l -1 ) for 7 days. The highest concentrations were found in digestive gland for cadmium and copper, and in gills for lead, and the lowest values were observed in the foot. Aspartate aminotransferase activity (AST), in general, was not inhibited by cadmium, lead or copper during the exposure. Only in clams exposed to cadmium (600 μg·l -1 , 7 days) and copper (20 μg·l -1 , 5 days) were observed significant differences (P -1 . A significant correlation (P<0.05) was observed between ALT and metal accumulation for cadmium, copper and lead in gills. In the case of soft body, only cadmium and lead showed a significant correlation. In summary, R. philippinarum can be considered a bioindicator species for cadmium and lead accumulation and ALT could be useful as biomarker of sublethal stress for these metals in soft tissues and gills. Only gills can be considered an adequate target tissue for copper. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  3. Inhibition of hypoxia-associated response and kynurenine production in response to hyperbaric oxygen as mechanisms involved in protection against experimental cerebral malaria.

    Science.gov (United States)

    Bastos, Marcele F; Kayano, Ana Carolina A V; Silva-Filho, João Luiz; Dos-Santos, João Conrado K; Judice, Carla; Blanco, Yara C; Shryock, Nathaniel; Sercundes, Michelle K; Ortolan, Luana S; Francelin, Carolina; Leite, Juliana A; Oliveira, Rafaella; Elias, Rosa M; Câmara, Niels O S; Lopes, Stefanie C P; Albrecht, Letusa; Farias, Alessandro S; Vicente, Cristina P; Werneck, Claudio C; Giorgio, Selma; Verinaud, Liana; Epiphanio, Sabrina; Marinho, Claudio R F; Lalwani, Pritesh; Amino, Rogerio; Aliberti, Julio; Costa, Fabio T M

    2018-03-20

    Cerebral malaria (CM) is a multifactorial syndrome involving an exacerbated proinflammatory status, endothelial cell activation, coagulopathy, hypoxia, and accumulation of leukocytes and parasites in the brain microvasculature. Despite significant improvements in malaria control, 15% of mortality is still observed in CM cases, and 25% of survivors develop neurologic sequelae for life-even after appropriate antimalarial therapy. A treatment that ameliorates CM clinical signs, resulting in complete healing, is urgently needed. Previously, we showed a hyperbaric oxygen (HBO)-protective effect against experimental CM. Here, we provide molecular evidence that HBO targets brain endothelial cells by decreasing their activation and inhibits parasite and leukocyte accumulation, thus improving cerebral microcirculatory blood flow. HBO treatment increased the expression of aryl hydrocarbon receptor over hypoxia-inducible factor 1-α (HIF-1α), an oxygen-sensitive cytosolic receptor, along with decreased indoleamine 2,3-dioxygenase 1 expression and kynurenine levels. Moreover, ablation of HIF-1α expression in endothelial cells in mice conferred protection against CM and improved survival. We propose that HBO should be pursued as an adjunctive therapy in CM patients to prolong survival and diminish deleterious proinflammatory reaction. Furthermore, our data support the use of HBO in therapeutic strategies to improve outcomes of non-CM disorders affecting the brain.-Bastos, M. F., Kayano, A. C. A. V., Silva-Filho, J. L., Dos-Santos, J. C. K., Judice, C., Blanco, Y. C., Shryock, N., Sercundes, M. K., Ortolan, L. S., Francelin, C., Leite, J. A., Oliveira, R., Elias, R. M., Câmara, N. O. S., Lopes, S. C. P., Albrecht, L., Farias, A. S., Vicente, C. P., Werneck, C. C., Giorgio, S., Verinaud, L., Epiphanio, S., Marinho, C. R. F., Lalwani, P., Amino, R., Aliberti, J., Costa, F. T. M. Inhibition of hypoxia-associated response and kynurenine production in response to hyperbaric oxygen

  4. Metabolomic changes demonstrate reduced bioavailability of tyrosine and altered metabolism of tryptophan via the kynurenine pathway with ingestion of medical foods in phenylketonuria.

    Science.gov (United States)

    Ney, Denise M; Murali, Sangita G; Stroup, Bridget M; Nair, Nivedita; Sawin, Emily A; Rohr, Fran; Levy, Harvey L

    2017-06-01

    Deficiencies of the monoamine neurotransmitters, such as dopamine synthesized from Tyr and serotonin synthesized from Trp, are of concern in PKU. Our objective was to utilize metabolomics analysis to assess monoamine metabolites in subjects with PKU consuming amino acid medical foods (AA-MF) and glycomacropeptide medical foods (GMP-MF). Subjects with PKU consumed a low-Phe diet combined with AA-MF or GMP-MF for 3weeks each in a randomized, controlled, crossover study. Metabolomic analysis was conducted by Metabolon, Inc. on plasma (n=18) and urine (n=9) samples. Catecholamines and 6-sulfatoxymelatonin were measured in 24-h urine samples. Intake of Tyr and Trp was ~50% higher with AA-MF, and AA-MF were consumed in larger quantities, less frequently during the day compared with GMP-MF. Performance on neuropsychological tests and concentrations of neurotransmitters derived from Tyr and Trp were not significantly different with AA-MF or GMP-MF. Plasma serotonin levels of gut origin were higher in subjects with variant compared with classical PKU, and with GMP-MF compared with AA-MF in subjects with variant PKU. Metabolomics analysis identified higher levels of microbiome-derived compounds synthesized from Tyr, such as phenol sulfate, and higher levels of compounds synthesized from Trp in the kynurenine pathway, such as quinolinic acid, with ingestion of AA-MF compared with GMP-MF. The Tyr from AA-MF is less bioavailable due, in part, to greater degradation by intestinal microbes compared with the Tyr from prebiotic GMP-MF. Research is needed to understand how metabolism of Trp via the kynurenine pathway and changes in the intestinal microbiota affect health for individuals with PKU. This trial is registered at www.clinicaltrials.gov as NCT01428258. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  5. Abnormalities in Functional Connectivity in Collegiate Football Athletes with and without a Concussion History: Implications and Role of Neuroactive Kynurenine Pathway Metabolites.

    Science.gov (United States)

    Meier, Timothy B; Lancaster, Melissa A; Mayer, Andrew R; Teague, T Kent; Savitz, Jonathan

    2017-02-15

    There is a great need to identify potential long-term consequences of contact sport exposure and to identify molecular pathways that may be associated with these changes. We tested the hypothesis that football players with (Ath-mTBI) (n = 25) and without a concussion history (Ath) (n = 24) have altered resting state functional connectivity in regions with previously documented structural changes relative to healthy controls without football or concussion history (HC) (n = 27). As a secondary aim, we tested the hypothesis that group differences in functional connectivity are moderated by the relative ratio of neuroprotective to neurotoxic metabolites of the kynurenine pathway. Ath-mTBI had significantly increased connectivity of motor cortex to the supplementary motor area relative to Ath and HC. In contrast, both Ath-mTBI and Ath had increased connectivity between the left orbital frontal cortex and the right lateral frontal cortex, and between the left cornu ammonis areas 2 and 3/dentate gyrus (CA2-3/DG) of the hippocampus and the middle and posterior cingulate cortices, relative to HC. The relationship between the ratio of plasma concentrations of kynurenic acid to quinolinic acid (KYNA/QUIN) and left pregenual anterior cingulate cortex connectivity to multiple regions as well as KYNA/QUIN and right CA2-3/DG connectivity to multiple regions differed significantly according to football and concussion history. The results suggest that football exposure with and without concussion history can have a significant effect on intrinsic brain connectivity and implicate the kynurenine metabolic pathway as one potential moderator of functional connectivity dependent on football exposure and concussion history.

  6. The inhibition of the kynurenine pathway prevents behavioral disturbances and oxidative stress in the brain of adult rats subjected to an animal model of schizophrenia.

    Science.gov (United States)

    Réus, Gislaine Z; Becker, Indianara R T; Scaini, Giselli; Petronilho, Fabricia; Oses, Jean P; Kaddurah-Daouk, Rima; Ceretta, Luciane B; Zugno, Alexandra I; Dal-Pizzol, Felipe; Quevedo, João; Barichello, Tatiana

    2018-02-02

    Evidence has shown that the kynurenine pathway (KP) plays a role in the onset of oxidative stress and also in the pathophysiology of schizophrenia. The aim of this study was to use a pharmacological animal model of schizophrenia induced by ketamine to investigate if KP inhibitors could protect the brains of Wistar rats against oxidative stress and behavioral changes. Ketamine, injected at the dose of 25mg/kg, increased spontaneous locomotor activity. However, the inhibitors of tryptophan 2,3-dioxygenase (TDO), indoleamine 2,3-dioxygenase (IDO) and kynurenine-3-monooxygenase (KMO) were able to reverse these changes. In addition, the IDO inhibitor prevented lipid peroxidation, and decreased the levels of protein carbonyl in the prefrontal cortex (PFC), hippocampus and striatum. It also increased the activity of superoxide dismutase (SOD) in the hippocampus, as well as increasing the levels of catalase activity in the PFC and hippocampus. The TDO inhibitor prevented lipid damage in the striatum and reduced the levels of protein carbonyl in the hippocampus and striatum. Also, the TDO inhibitor increased the levels of SOD activity in the striatum and CAT activity in the hippocampus of ketamine-induced pro-oxidant effects. Lipid damage was not reversed by the KMO inhibitor. The KMO inhibitor increased the levels of SOD activity in the hippocampus, and reduced the levels of protein carbonyl while elevating the levels of CAT activity in the striatum of rats that had been injected with ketamine. Our findings revealed that the KP pathway could be a potential mechanism by which a schizophrenia animal model induced by ketamine could cause interference by producing behavioral disturbance and inducing oxidative stress in the brain, suggesting that the inhibition of the KP pathway could be a potential target in treating schizophrenia. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Development of a Surface Plasmon Resonance Assay for the Characterization of Small-Molecule Binding Kinetics and Mechanism of Binding to Kynurenine 3-Monooxygenase.

    Science.gov (United States)

    Poda, Suresh B; Kobayashi, Masakazu; Nachane, Ruta; Menon, Veena; Gandhi, Adarsh S; Budac, David P; Li, Guiying; Campbell, Brian M; Tagmose, Lena

    2015-10-01

    Kynurenine 3-monooxygenase (KMO), a pivotal enzyme in the kynurenine pathway, was identified as a potential therapeutic target for treating neurodegenerative and psychiatric disorders. In this article, we describe a surface plasmon resonance (SPR) assay that delivers both kinetics and the mechanism of binding (MoB) data, enabling a detailed characterization of KMO inhibitors for the enzyme in real time. SPR assay development included optimization of the protein construct and the buffer conditions. The stability and inhibitor binding activity of the immobilized KMO were significantly improved when the experiments were performed at 10°C using a buffer containing 0.05% n-dodecyl-β-d-maltoside (DDM) as the detergent. The KD values of the known KMO inhibitors (UPF648 and RO61-8048) from the SPR assay were in good accordance with the biochemical LC/MS/MS assay. Also, the SPR assay was able to differentiate the binding kinetics (k(a) and k(d)) of the selected unknown KMO inhibitors. For example, the inhibitors that showed comparable IC50 values in the LC/MS/MS assay displayed differences in their residence time (τ = 1/k(d)) in the SPR assay. To better define the MoB of the inhibitors to KMO, an SPR-based competition assay was developed, which demonstrated that both UPF648 and RO61-8048 bound to the substrate-binding site. These results demonstrate the potential of the SPR assay for characterizing the affinity, the kinetics, and the MoB profiles of the KMO inhibitors.

  8. Systemic L-Kynurenine sulfate administration disrupts object recognition memory, alters open field behavior and decreases c-Fos immunopositivity in C57Bl/6 mice.

    Science.gov (United States)

    Varga, Dániel; Herédi, Judit; Kánvási, Zita; Ruszka, Marian; Kis, Zsolt; Ono, Etsuro; Iwamori, Naoki; Iwamori, Tokuko; Takakuwa, Hiroki; Vécsei, László; Toldi, József; Gellért, Levente

    2015-01-01

    L-Kynurenine (L-KYN) is a central metabolite of tryptophan degradation through the kynurenine pathway (KP). The systemic administration of L-KYN sulfate (L-KYNs) leads to a rapid elevation of the neuroactive KP metabolite kynurenic acid (KYNA). An elevated level of KYNA may have multiple effects on the synaptic transmission, resulting in complex behavioral changes, such as hypoactivity or spatial working memory deficits. These results emerged from studies that focused on rats, after low-dose L-KYNs treatment. However, in several studies neuroprotection was achieved through the administration of high-dose L-KYNs. In the present study, our aim was to investigate whether the systemic administration of a high dose of L-KYNs (300 mg/bwkg; i.p.) would produce alterations in behavioral tasks (open field or object recognition) in C57Bl/6j mice. To evaluate the changes in neuronal activity after L-KYNs treatment, in a separate group of animals we estimated c-Fos expression levels in the corresponding subcortical brain areas. The L-KYNs treatment did not affect the general ambulatory activity of C57Bl/6j mice, whereas it altered their moving patterns, elevating the movement velocity and resting time. Additionally, it seemed to increase anxiety-like behavior, as peripheral zone preference of the open field arena emerged and the rearing activity was attenuated. The treatment also completely abolished the formation of object recognition memory and resulted in decreases in the number of c-Fos-immunopositive-cells in the dorsal part of the striatum and in the CA1 pyramidal cell layer of the hippocampus. We conclude that a single exposure to L-KYNs leads to behavioral disturbances, which might be related to the altered basal c-Fos protein expression in C57Bl/6j mice.

  9. Enzyme characteristics of aminotransferase FumI of Sphingopyxis sp. MTA144 for deamination of hydrolyzed fumonisin B₁.

    Science.gov (United States)

    Hartinger, Doris; Schwartz, Heidi; Hametner, Christian; Schatzmayr, Gerd; Haltrich, Dietmar; Moll, Wulf-Dieter

    2011-08-01

    Fumonisins are carcinogenic mycotoxins that are frequently found as natural contaminants in maize from warm climate regions around the world. The aminotransferase FumI is encoded as part of a gene cluster of Sphingopyxis sp. MTA144, which enables this bacterial strain to degrade fumonisin B(1) and related fumonisins. FumI catalyzes the deamination of the first intermediate of the catabolic pathway, hydrolyzed fumonisin B(1). We used a preparation of purified, His-tagged FumI, produced recombinantly in Escherichia coli in soluble form, for enzyme characterization. The structure of the reaction product was studied by NMR and identified as 2-keto hydrolyzed fumonisin B(1). Pyruvate was found to be the preferred co-substrate and amino group receptor (K (M) = 490 μM at 10 μM hydrolyzed fumonisin B(1)) of FumI, but other α-keto acids were also accepted as co-substrates. Addition of the co-enzyme pyridoxal phosphate to the enzyme preparation enhanced activity, and saturation was already reached at the lowest tested concentration of 10 μM. The enzyme showed activity in the range of pH 6 to 10 with an optimum at pH 8.5, and in the range of 6°C to 50°C with an optimum at 35°C. The aminotransferase worked best at low salt concentration. FumI activity could be recovered after preincubation at pH 4.0 or higher, but not lower. The aminotransferase was denatured after preincubation at 60°C for 1 h, and the residual activity was also reduced after preincubation at lower temperatures. At optimum conditions, the kinetic parameters K (M) = 1.1 μM and k (cat) = 104/min were determined with 5 mM pyruvate as co-substrate. Based on the enzyme characteristics, a technological application of FumI, in combination with the fumonisin carboxylesterase FumD for hydrolysis of fumonisins, for deamination and detoxification of hydrolyzed fumonisins seems possible, if the enzyme properties are considered.

  10. Preoperative Aspartate Aminotransferase-to-Platelet Ratio Index Predicts Perioperative Liver-Related Complications Following Liver Resection for Colorectal Cancer Metastases

    DEFF Research Database (Denmark)

    Amptoulach, S.; Gross, G.; Sturesson, C.

    2017-01-01

    -related). In multivariate regression analysis, the aspartate aminotransferase-to-platelet ratio index was independently associated with liver-related complications (odds ratio: 1.149, p = 0.003) and perioperative liver failure (odds ratio: 1.155, p = 0.012). The latter was also true in the subcohort of patients......Background and Aims: There are limited data on the potential role of preoperative non-invasive markers, specifically the aspartate-to-alanine aminotransferase ratio and the aspartate aminotransferase-to-platelet ratio index, in predicting perioperative liver-related complications after hepatectomy...... collected from medical records. The nontumorous liver parenchyma in the surgical specimens of 31 patients was re-evaluated. Results: Overall, 215 patients were included. In total, 40% underwent neoadjuvant chemotherapy and 47% major resection, while 47% had perioperative complications (6% liver...

  11. Aminotransferase elevation in HIV/hepatitis B virus co-infected patients treated with two active hepatitis B virus drugs.

    Science.gov (United States)

    Jain, Mamta K; Parekh, Nimisha K; Hester, Jill; Lee, William M

    2006-12-01

    Discerning drug hepatotoxicity from viral hepatitis flares remains an ongoing problem unique to patients coinfected with HIV and hepatitis B (HBV). We present three such coinfected patients who have been on two anti-HBV agents, lamivudine and tenofovir disoproxil fumarate simultaneously, as part of highly active antiretroviral therapy (HAART). All three developed significant aminotransferase elevations 6-12 weeks after initiation of HAART despite being on two active HBV drugs. Two of the three patients were initially thought to have drug-related hepatotoxicity from HIV medications. It seems more likely that all three patients demonstrated hepatitis B reactivation of differing severity as the result of varying degrees of immune recovery. Distinguishing clearly between drug-related hepatotoxicity and hepatitis reactivation may be difficult but is important as their clinical management differs.

  12. Indole-3-acetic acid biosynthetic pathway and aromatic amino acid aminotransferase activities in Pantoea dispersa strain GPK.

    Science.gov (United States)

    Kulkarni, G B; Nayak, A S; Sajjan, S S; Oblesha, A; Karegoudar, T B

    2013-05-01

    This investigation deals with the production of IAA by a bacterial isolate Pantoea dispersa strain GPK (PDG) identified by 16S rRNA gene sequence analysis. HPLC and Mass spectral analysis of metabolites from bacterial spent medium revealed that, IAA production by PDG is Trp-dependent and follows indole-3-pyruvic acid (IPyA) pathway. Substrate specificity study of aromatic amino acid aminotransferase (AAT) showed high activities, only when tryptophan (Trp) and α-ketoglutarate (α-kg) were used as substrates. AAT is highly specific for Trp and α-kg as amino group donor and acceptor, respectively. The effect of exogenous IAA on bacterial growth was established. Low concentration of exogenous IAA induced the growth, whereas high concentration decreased the growth of bacterium. PDG treatment significantly increased the root length, shoot length and dry mass of the chickpea and pigeon pea plants. © 2013 The Society for Applied Microbiology.

  13. Identification of branched-chain amino acid aminotransferases active towards (R)-(+)-1-phenylethylamine among PLP fold type IV transaminases.

    Science.gov (United States)

    Bezsudnova, Ekaterina Yu; Dibrova, Daria V; Nikolaeva, Alena Yu; Rakitina, Tatiana V; Popov, Vladimir O

    2018-04-10

    New class IV transaminases with activity towards L-Leu, which is typical of branched-chain amino acid aminotransferases (BCAT), and with activity towards (R)-(+)-1-phenylethylamine ((R)-PEA), which is typical of (R)-selective (R)-amine:pyruvate transaminases, were identified by bioinformatics analysis, obtained in recombinant form, and analyzed. The values of catalytic activities in the reaction with L-Leu and (R)-PEA are comparable to those measured for characteristic transaminases with the corresponding specificity. Earlier, (R)-selective class IV transaminases were found to be active, apart from (R)-PEA, only with some other (R)-primary amines and D-amino acids. Sequences encoding new transaminases with mixed type of activity were found by searching for changes in the conserved motifs of sequences of BCAT by different bioinformatics tools. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Mycobacterium Lysine ε-aminotransferase is a novel alarmone metabolism related persister gene via dysregulating the intracellular amino acid level.

    Science.gov (United States)

    Duan, Xiangke; Li, Yunsong; Du, Qinglin; Huang, Qinqin; Guo, Siyao; Xu, Mengmeng; Lin, Yanping; Liu, Zhidong; Xie, Jianping

    2016-01-25

    Bacterial persisters, usually slow-growing, non-replicating cells highly tolerant to antibiotics, play a crucial role contributing to the recalcitrance of chronic infections and treatment failure. Understanding the molecular mechanism of persister cells formation and maintenance would obviously inspire the discovery of new antibiotics. The significant upregulation of Mycobacterium tuberculosis Rv3290c, a highly conserved mycobacterial lysine ε-aminotransferase (LAT) during hypoxia persistent model, suggested a role of LAT in persistence. To test this, a lat deleted Mycobacterium smegmatis was constructed. The expression of transcriptional regulator leucine-responsive regulatory protein (LrpA) and the amino acids abundance in M. smegmatis lat deletion mutants were lowered. Thus, the persistence capacity of the deletion mutant was impaired upon norfloxacin exposure under nutrient starvation. In summary, our study firstly reported the involvement of mycobacterium LAT in persister formation, and possibly through altering the intracellular amino acid metabolism balance.

  15. Branched-chain fatty acid biosynthesis in a branched-chain amino acid aminotransferase mutant of Staphylococcus carnosus

    DEFF Research Database (Denmark)

    Beck, Hans Christian

    2005-01-01

    Fatty acid biosynthesis by a mutant strain of Staphylococcus carnosus deficient in branched-chain amino acid aminotransferase (IlvE) activity was analysed. This mutant was unable to produce the appropriate branched-chain alpha-ketoacid precursors for branched-chain fatty acid biosynthesis from...... in rich medium and growth in defined medium supplemented with 2-methylpropanoic acid lead to extensive alteration of the fatty acid composition in the cell membrane. In rich medium, a change from 51.7% to 17.1% anteiso-C15:0, and from 3.6% to 33.9% iso-C14:0 fatty acids as compared to the wild-type strain...... for 2-methylpropanoic acid production, revealing that the IlvE protein plays an important, but not essential role in the biosynthesis of branched-chain fatty acids and secondary metabolites in S. carnosus....

  16. Enhancement of solubility in Escherichia coli and purification of an aminotransferase from Sphingopyxis sp. MTA144 for deamination of hydrolyzed fumonisin B1

    Directory of Open Access Journals (Sweden)

    Hartinger Doris

    2010-08-01

    Full Text Available Abstract Background Fumonisin B1 is a cancerogenic mycotoxin produced by Fusarium verticillioides and other fungi. Sphingopyxis sp. MTA144 can degrade fumonisin B1, and a key enzyme in the catabolic pathway is an aminotransferase which removes the C2-amino group from hydrolyzed fumonisin B1. In order to study this aminotransferase with respect to a possible future application in enzymatic fumonisin detoxification, we attempted expression of the corresponding fumI gene in E. coli and purification of the enzyme. Since the aminotransferase initially accumulated in inclusion bodies, we compared the effects of induction level, host strain, expression temperature, solubility enhancers and a fusion partner on enzyme solubility and activity. Results When expressed from a T7 promoter at 30°C, the aminotransferase accumulated invariably in inclusion bodies in DE3 lysogens of the E. coli strains BL21, HMS174, Rosetta 2, Origami 2, or Rosetta-gami. Omission of the isopropyl-beta-D-thiogalactopyranoside (IPTG used for induction caused a reduction of expression level, but no enhancement of solubility. Likewise, protein production but not solubility correlated with the IPTG concentration in E. coli Tuner(DE3. Addition of the solubility enhancers betaine and sorbitol or the co-enzyme pyridoxal phosphate showed no effect. Maltose-binding protein, used as an N-terminal fusion partner, promoted solubility at 30°C or less, but not at 37°C. Low enzyme activity and subsequent aggregation in the course of purification and cleavage indicated that the soluble fusion protein contained incorrectly folded aminotransferase. Expression in E. coli ArcticExpress(DE3, which co-expresses two cold-adapted chaperonins, at 11°C finally resulted in production of appreciable amounts of active enzyme. Since His tag-mediated affinity purification from this strain was hindered by co-elution of chaperonin, two steps of chromatography with optimized imidazole concentration in the

  17. The efficacy of aspartate aminotransferase-toplatelet ratio index for assessing hepatic fibrosis in childhood nonalcoholic steatohepatitis for medical practice

    Directory of Open Access Journals (Sweden)

    Earl Kim

    2013-01-01

    Full Text Available Purpose: Childhood obesity is associated with nonalcoholic fatty liver disease (NAFLD, and it has become one of the most common causes of childhood chronic liver diseases which significant as a cause of liver related mortality and morbidity in children in the United States. The development of simpler and easier clinical indices for medical practice is needed to identify advanced hepatic fibrosis in childhood NAFLD instead of invasive method like liver biopsy. FibroScan and aspartate aminotransferase (AST-to-platelet ratio index (APRI have been proposed as a simple and noninvasive predictor to evaluate hepatic fibrosis in several liver diseases. APRI could be a good alternative to detect pathologic change in childhood NAFLD. The purpose of this study is to validate the efficacy of APRI for assessing hepatic fibrosis in childhood NAFLD based on FibroScan. Methods: This study included 23 children with NAFLD who underwent FibroScan. Clinical, laboratory and radiological evaluation including APRI was performed. To confirm the result of this study, 6 patients received liver biopsy. Results: Factors associated with hepatic fibrosis (stiffness measurement &gt;5.9 kPa Fibroscan were triglyceride, AST, alanine aminotransferase, platelet count, APRI and collagen IV. In multivariate analysis, APRI were correlated with hepatic fibrosis (&gt;5.9 kPa. In receiver operating characteristics curve, APRI of meaningful fibrosis (cutoff value, 0.4669; area under the receiver operating characteristics, 0.875 presented sensitivity of 94%, specificity of 66%, positive predictive value of 94%, and negative predictive value of 64%. Conclusion: APRI might be a noninvasive, simple, and readily available method for medical practice to predict hepatic fibrosis of childhood NAFLD.

  18. Effects of 45Ca on murine skeletal muscle. 3

    International Nuclear Information System (INIS)

    Malhotra, R.K.; Asotra, K.; Katoch, S.S.; Krishan, K.

    1983-01-01

    Swiss albino mice were injected intraperitoneally with 3.7x10 4 Bq and 7.4x10 4 Bq 45 Ca/g body weight. Mice of both dose groups were autopsied on days 1, 3, 5, 7, 14 and 28 and activities of alanine aminotransferase and aspartate aminotransferase bioassayed in diaphragm and gastrocnemius in 45 Ca-treated and normal mice. Alanine aminotransferase activity in the two muscles increased in response to 45 Ca administration suggesting a stepped up utilization of alanine in glucose generation. Aspartate aminotransferase levels, on the other hand, diminished in both the 45 Ca-treated muscles and are maintained at low values throughout the 28 day period of study. The results suggest an innate ability of skeletal muscle to selectively utilize either of the two glucogenic amino acids during radiation stress. The data are discussed in light of previous findings on glycogen accumulation in irradiated skeletal muscle. (author)

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

    Directory of Open Access Journals (Sweden)

    Adele Blankfield

    2013-01-01

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

  20. Reemergence of Murine Typhus in the US

    Centers for Disease Control (CDC) Podcasts

    2015-04-21

    Dr. Lucas Blanton discusses the Reemergence of Murine Typhus in Galveston Texas in 2013.  Created: 4/21/2015 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 4/27/2015.

  1. SERUM ACTIVITIES OF ASPARTATE AMINOTRANSFERASE, CREATINE KINASE AND LACTATE DEHYDROGENASE IN HORSES WITH COLIC ATIVIDADE SÉRICA DAS ENZIMAS ASPARTATO AMINOTRANSFERASE, CREATINA QUINASE E LACTATO DESIDROGENASE EM EQÜINOS COM CÓLICA

    Directory of Open Access Journals (Sweden)

    Aureo Evangelista Santana

    2008-12-01

    Full Text Available Seventy equines distributed in two experimental groups were used, G1 (20 healthy equines, and G2 (50 equines with colic. Blood samples were obtained by jugular vein puncture in ten different moments. The variables aspartate aminotransferase (AST, creatine kinase (CK, and lactate dehydrogenase (LDH were determined by spectrophotometric assay using specific reagents. The average values presented by the animals of the G2 for variables CK, AST, and LDH were higher (P<0.05 than the values presented by the animals of the G1 in all the evaluation moments. The results showed for G2 animals suggest the existence of acute muscle injury. The muscle injuries in equines with colic were attributed to the tissue hypoperfusion, and the muscular damage.

    KEY WORDS: Acute abdomen, horses, muscles enzyme. De setenta eqüinos, distribuídos em dois grupos experimentais – G1 (vinte eqüinos hígidos e G2 (cinqüenta eqüinos com cólica –, colheram-se amostras de sangue em dez diferentes momentos, mediante punção da jugular, para a determinação da atividade sérica das enzimas aspartato aminotransferase (AST, creatina quinase (CK e lactato desidrogenase (LDH. Os valores médios apresentados pelos animais do G2, para as variáveis CK, AST e LDH, foram superiores (P<0,05 aos valores médios apresentados pelos animais do G1 em todos os momentos de avaliação. Os resultados apresentados pelos animais com cólica (G2 sugerem a existência de lesão muscular aguda, porém com tendência a cura, e foram atribuídos a hipoperfusão tecidual e a traumas musculares. A análise seriada das enzimas CK, AST e LDH auxilia tanto no diagnóstico de lesões musculares em eqüinos com cólica como no acompanhamento da evolução do processo de cura.

    PALAVRAS-CHAVES: Abdômen agudo, cavalos, enzimas musculares.

  2. (1S, 3S)-3-amino-4-difluoromethylenyl-1-cyclopentanoic acid (CPP-115), a potent gamma-aminobutyric acid aminotransferase inactivator for the treatment of cocaine addiction

    DEFF Research Database (Denmark)

    Pan, Yue; Gerasimov, Madina R; Kvist, Trine

    2012-01-01

    Vigabatrin, a GABA aminotransferase (GABA-AT) inactivator, is used to treat infantile spasms and refractory complex partial seizures and is in clinical trials to treat addiction. We evaluated a novel GABA-AT inactivator (CPP-115) and observed that it does not exhibit other GABAergic or off-target...

  3. Coffee consumption is associated with lower serum aminotransferases in the general Korean population and in those at high risk for hepatic disease.

    Science.gov (United States)

    Oh, Myueng Guen; Han, Mi Ah; Kim, Man Woo; Park, Chan Guk; Kim, Young Dae; Lee, Jun

    2016-12-01

    The favourable effects of coffee on liver enzymes have been reported worldwide. This study investigated the association between coffee consumption and serum aminotransferase concentration in Korean adults. Data were obtained from the fourth and fifth Korea National Health and Nutrition Examination Surveys. Elevated alanine aminotransferase (ALT) and aspartate aminotransferase (AST) concentration were defined as >30 IU/L for men and >19 IU/L for women. The risk of elevated ALT and AST according to general characteristics and frequency of coffee consumption were tested by chi-square tests and multiple logistic regression analyses. The prevalence of elevated ALT was 27.4%, 27.8%, and 26.9% in subjects who drank =2 times/day, respectively. The proportions of individuals with elevated AST were 32.5%, 33.1%, and 26.7% in subjects who drank =2 times/day, respectively. The aORs for elevated ALT and AST were significantly lower in subjects who drank >=2 times of coffee/day than in those who drank =2 times/day was associated with lower ORs for elevated ALT in the high-risk group overall and in the viral hepatitis and obesity subgroups, respectively. In sensitivity analysis, reduced frequency of coffee consumption was associated with an increased risk for elevated liver enzymes, although an association between coffee consumption and elevated ALT was not observed in women or current smokers. Higher coffee consumption was associated with lower risk of elevated aminotransferase concentration in Korean adults.

  4. Serum aminotransferases in nonalcoholic fatty liver disease are a signature of liver metabolic perturbations at the amino acid and Krebs cycle level.

    Science.gov (United States)

    Sookoian, Silvia; Castaño, Gustavo O; Scian, Romina; Fernández Gianotti, Tomas; Dopazo, Hernán; Rohr, Cristian; Gaj, Graciela; San Martino, Julio; Sevic, Ina; Flichman, Diego; Pirola, Carlos J

    2016-02-01

    Extensive epidemiologic studies have shown that cardiovascular disease and the metabolic syndrome (MetS) are associated with serum concentrations of liver enzymes; however, fundamental characteristics of this relation are currently unknown. We aimed to explore the role of liver aminotransferases in nonalcoholic fatty liver disease (NAFLD) and MetS. Liver gene- and protein-expression changes of aminotransferases, including their corresponding isoforms, were evaluated in a case-control study of patients with NAFLD (n = 42), which was proven through a biopsy (control subjects: n = 10). We also carried out a serum targeted metabolite profiling to the glycolysis, gluconeogenesis, and Krebs cycle (n = 48) and an exploration by the next-generation sequencing of aminotransferase genes (n = 96). An in vitro study to provide a biological explanation of changes in the transcriptional level and enzymatic activity of aminotransferases was included. Fatty liver was associated with a deregulated liver expression of aminotransferases, which was unrelated to the disease severity. Metabolite profiling showed that serum aminotransferase concentrations are a signature of liver metabolic perturbations, particularly at the amino acid metabolism and Krebs cycle level. A significant and positive association between systolic hypertension and liver expression levels of glutamic-oxaloacetic transaminase 2 (GOT2) messenger RNA (Spearman R = 0.42, P = 0.03) was observed. The rs6993 located in the 3' untranslated region of the GOT2 locus was significantly associated with features of the MetS, including arterial hypertension [P = 0.028; OR: 2.285 (95% CI: 1.024, 5.09); adjusted by NAFLD severity] and plasma lipid concentrations. In the context of an abnormal hepatic triglyceride accumulation, circulating aminotransferases rise as a consequence of the need for increased reactions of transamination to cope with the liver metabolic derangement that is associated with greater gluconeogenesis and

  5. Attention-deficit hyperactivity disorder (ADHD and glial integrity: an exploration of associations of cytokines and kynurenine metabolites with symptoms and attention

    Directory of Open Access Journals (Sweden)

    Schimmelmann Benno G

    2010-06-01

    Full Text Available Abstract Background In contrast to studies of depression and psychosis, the first part of this study showed no major differences in serum levels of cytokines and tryptophan metabolites between healthy children and those with attention-deficit/hyperactivity disorder of the combined type (ADHD. Yet, small decreases of potentially toxic kynurenine metabolites and increases of cytokines were evident in subgroups. Therefore we examined predictions of biochemical associations with the major symptom clusters, measures of attention and response variability. Methods We explored systematically associations of 8 cytokines (indicators of pro/anti-inflammatory function and 5 tryptophan metabolites with symptom ratings (e.g. anxiety, opposition, inattention and continuous performance test (CPT measures (e.g. movement, response time (RT, variability in 35 ADHD (14 on medication and 21 control children. Predictions from linear regressions (controlled by the false discovery rate confirmed or disconfirmed partial correlations accounting for age, body mass and socio-economic status. Results (1 Total symptom ratings were associated with increases of the interleukins IL-16 and IL-13, where relations of IL-16 (along with decreased S100B with hyperactivity, and IL-13 with inattention were notable. Opposition ratings were predicted by increased IL-2 in ADHD and IL-6 in control children. (2 In the CPT, IL-16 related to motor measures and errors of commission, while IL-13 was associated with errors of omission. Increased RT variability related to lower TNF-α, but to higher IFN-γ levels. (3 Tryptophan metabolites were not significantly related to symptoms. But increased tryptophan predicted errors of omission, its breakdown predicted errors of commission and kynurenine levels related to faster RTs. Conclusions Many associations were found across diagnostic groups even though they were more marked in one group. This confirms the quantitative trait nature of these

  6. Alanine aminotransferase is associated with an adverse nocturnal blood glucose profile in individuals with normal glucose regulation.

    Directory of Open Access Journals (Sweden)

    Jian Zhou

    Full Text Available OBJECTIVE: Although the association between alanine aminotransferase (ALT levels and risk of type 2 diabetes is well-studied, the effects of slightly increased ALT levels within the normal range on the temporal normal glucose profile remains poorly understood. METHODS: A total of 322 Chinese subjects without impaired glucose tolerance or previous diagnoses of diabetes were recruited for study from 10 hospitals in urban areas across China. All subjects wore a continuous glucose monitoring (CGM system for three consecutive days. The diurnal (06∶00-20∶00 and nocturnal (20∶00-06∶00 mean blood glucose (MBG levels were calculated. Subjects were stratified by ALT quartile level and correlation analyses were performed. RESULTS: The median ALT level was 17 IU/L, and subjects with ALT ≥17 IU/L had higher nocturnal MBG level than those with ALT 0.05. Multivariate stepwise regression analysis of elevated nocturnal MBG identified increased HOMA-IR, elevated ALT levels, and decreased homeostatic model assessment of ß-cell function as independent factors (all, P<0.05. CONCLUSIONS: Mildly elevated ALT levels, within the normal range, are associated with unfavorable nocturnal glucose profiles in Chinese subjects with normal glucose regulation.

  7. Crystallization and preliminary X-ray diffraction analysis of L,L-diaminopimelate aminotransferase (DapL) from Chlamydomonas reinhardtii.

    Science.gov (United States)

    Hudson, André O; Girón, Irma; Dobson, Renwick C J

    2011-01-01

    In the anabolic synthesis of diaminopimelate and lysine in plants and in some bacteria, the enzyme L,L-diaminopimelate aminotransferase (DapL; EC 2.6.1.83) catalyzes the conversion of tetrahydrodipicolinic acid (THDPA) to L,L-diaminopimelate, bypassing the DapD, DapC and DapE enzymatic steps in the bacterial acyl pathways. Here, the cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of DapL from the alga Chlamydomonas reinhardtii are presented. Protein crystals were grown in conditions containing 25% (w/v) PEG 3350 and 200 mM lithium sulfate and initially diffracted to ∼1.35 Å resolution. They belonged to space group P2(1)2(1)2(1), with unit-cell parameters a=58.9, b=91.8, c=162.9 Å. The data were processed to 1.55 Å resolution with an Rmerge of 0.081, an Rp.i.m. of 0.044, an Rr.i.m of 0.093 and a VM of 2.28 Å3 Da(-1).

  8. Prevalence of metabolic syndrome and risks of abnormal serum alanine aminotransferase in Hispanics: a population-based study.

    Directory of Open Access Journals (Sweden)

    Jen-Jung Pan

    Full Text Available Study the prevalence of metabolic syndrome (MS and risk factors for and association with elevated alanine aminotransferase (ALT as markers of hepatic injury in a large Hispanic health disparity cohort with high rates of obesity.Analysis of data from a prospective cross-sectional population based study. From 2004-7, we randomly recruited 2000 community participants to the Cameron County Hispanic Cohort collecting extensive socioeconomic, clinical and laboratory data. We excluded 153 subjects due to critical missing data. Pearson chi-square tests and Student's t-tests were used for categorical and continuous variable analysis, respectively. Logistic regression analysis was performed to determine the risk factors for elevated ALT.The mean age of the cohort was 45 years and 67% were females. The majority of the cohort was either overweight (32.4% or obese (50.7%. Almost half (43.7% had MS and nearly one-third diabetes. Elevated ALT level was more prevalent in males than females. Obesity was a strong risk for abnormal ALT in both genders. Hypertriglyceridemia, hypercholesterolemia and young age were risks for elevated ALT in males only, whereas increased fasting plasma glucose was associated with elevated ALT in females only.We identified high prevalence of MS and markers of liver injury in this large Mexican American cohort with gender differences in prevalence and risk factors, with younger males at greatest risk.

  9. Ornithine aminotransferase (OAT): recombination between an X-linked OAT sequence (7.5 kb) and the Norrie disease locus.

    Science.gov (United States)

    Ngo, J T; Bateman, J B; Spence, M A; Cortessis, V; Sparkes, R S; Kivlin, J D; Mohandas, T; Inana, G

    1990-01-01

    A human ornithine aminotransferase (OAT) locus has been mapped to the Xp11.2, as has the Norrie disease locus. We used a cDNA probe to investigate a 3-generation UCLA family with Norrie disease; a 4.2-kb RFLP was detected and a maximum lod score of 0.602 at zero recombination fraction was calculated. We used the same probe to study a second multigeneration family with Norrie disease from Utah. A different RFLP of 7.5 kb in size was identified and a recombinational event between the OAT locus represented by this RFLP and the disease loci was observed. Linkage analysis of these two loci in this family revealed a maximum load score of 1.88 at a recombination fraction of 0.10. Although both families have affected members with the same disease, the lod scores are reported separately because the 4.2- and 7.5-kb RFLPs may represent two different loci for the X-linked OAT.

  10. Aspartate aminotransferase-to-platelet ratio index for fibrosis and cirrhosis prediction in chronic hepatitis C patients

    Directory of Open Access Journals (Sweden)

    Roberto Gomes da Silva Junior

    Full Text Available In chronic hepatitis C (CHC, liver biopsy is the gold standard method for assessing liver histology, however it is invasive and can have complications. Non-invasive markers have been proposed and aspartate aminotransferase (AST-to-platelet ratio index (APRI has been shown as an easy and inexpensive marker of liver fibrosis. This study evaluated the diagnostic performance of APRI for significant fibrosis and cirrhosis prediction in CHC patients. This study included treatment-naive CHC patients who had undergone liver biopsy from January 2000 to August 2006. All histological slides were reviewed according to the METAVIR system. APRI was calculated based on laboratory results performed within four months from the biopsy. Twenty-eight (56% patients had significant fibrosis (F2-F4 and 13 (26% had cirrhosis (F4. The area under ROC curves of APRI for predicting significant fibrosis and cirrhosis were 0.92 (0.83-1.00 and 0.92 (0.85-1.00, respectively. Using cut-off values recommended by prior studies, significant fibrosis could be identified, in accordance with liver biopsy, in 44% and cirrhosis in 66% of patients. APRI could identify significant fibrosis and cirrhosis at a high degree of accuracy in studied patients.

  11. Liver peroxisomal alanine:glyoxylate aminotransferase and the effects of mutations associated with Primary Hyperoxaluria Type I: An overview.

    Science.gov (United States)

    Oppici, Elisa; Montioli, Riccardo; Cellini, Barbara

    2015-09-01

    Liver peroxisomal alanine:glyoxylate aminotransferase (AGT) (EC 2.6.1.44) catalyses the conversion of l-alanine and glyoxylate to pyruvate and glycine, a reaction that allows glyoxylate detoxification. Inherited mutations on the AGXT gene encoding AGT lead to Primary Hyperoxaluria Type I (PH1), a rare disorder characterized by the deposition of calcium oxalate crystals primarily in the urinary tract. Here we describe the results obtained on the biochemical features of AGT as well as on the molecular and cellular effects of polymorphic and pathogenic mutations. A complex scenario on the molecular pathogenesis of PH1 emerges in which the co-inheritance of polymorphic changes and the condition of homozygosis or compound heterozygosis are two important factors that determine the enzymatic phenotype of PH1 patients. All the reported data represent relevant steps toward the understanding of genotype/phenotype correlations, the prediction of the response of the patients to the available therapies, and the development of new therapeutic approaches. This article is part of a Special Issue entitled: Cofactor-dependent proteins: evolution, chemical diversity and bio-applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Effect of Arsenic and Chromium on the Serum Amino-Transferases Activity in Indian Major Carp, Labeo rohita

    Directory of Open Access Journals (Sweden)

    Anjaneyulu Yerramilli

    2007-09-01

    Full Text Available Arsenic and hexavalent chromium toxicity results from their ability to interact with sulfahydryl groups of proteins and enzymes, and to substitute phosphorus in a variety of biochemical reactions. Alanine aminotransferase (ALT; E.C: 2.6.1.2 and Aspartate amino transferase (AST; EC 2.6.1.1 play a crucial role in transamination reactions and can be used as potential biomarkers to indicate hepatotoxicity and cellular damage. While histopathological studies in liver tissue require more time and expertise, simple and reliable biochemical analysis of ALT and AST can be used for a rapid assessment of tissue and cellular damage within 96 h. The main objective of this study was to determine the acute effects of arsenic and hexavalent chromium on the activity of ALT and AST in the Indian major carp, Labeo rohita for 24 h and 96 h. Significant increase in the activity of ALT (P < 0.01 from controls in arsenic exposed fish indicates serious hepatic damage and distress condition to the fish. However, no such significant changes were observed in chromium-exposed fish suggesting that arsenic is more toxic to the fish. These findings indicate that ALT and AST are candidate biomarkers for arsenic-induced hepatotoxicity in Labeo rohita.

  13. Increased alanine aminotransferase levels and associated characteristics among newly diagnosed type 2 diabetes patients: Results from the DD2 study

    DEFF Research Database (Denmark)

    Mor, Anil; Thomsen, Reimar W.; Rungby, Jørgen

    Objectives: Elevated levels of serum alanine aminotransferase (ALAT) have been linked with non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), insulin resistance and the metabolic syndrome in type 2 diabetes (T2D) patients. We examined ALAT levels in newly diagnosed T2D...... quartile (>32IU/L / >41IU/L for women/men). As compared to people with ALAT values in the lowest quartile, those with high ALAT were younger (median age 57 vs. 64 years, pobese (median BMI 31.2 vs. 29.1 kg/m2, p=0.004), and had a larger waist circumference (111 vs. 101 cm, p....0001) and higher median CRP levels (2.8 vs. 1.8 mg/L, p=0.0147). They also had substantially poorer glucose control (HbA1c 7.40 vs. 6.90%, p=0.084; fasting blood glucose 7.56 vs. 6.86 mmol/L, pvs. 4.15 mmol/L, p=0.006), whereas blood pressure was similar...

  14. Relationship of creatine kinase, aspartate aminotransferase, lactate dehydrogenase, and proteinuria to cardiomyopathy in the owl monkey (Aotus vociferans)

    Energy Technology Data Exchange (ETDEWEB)

    Gozalo, Alfonso S.; Chavera, Alfonso; Montoya, Enrique J.; Takano, Juan; Weller, Richard E.

    2008-02-01

    The purpose of this study was to determine serum reference values for crea- tine kinase (CK), aspartate aminotransferase (AST), and lactate dehydroge- nase (LDH) in captive-born and wild-caught owl monkeys to assess their usefulness for diagnosing myocardial disease. Urine samples were also collected and semi-quantitative tests performed. There was no statistically significant difference between CK, AST, and LDH when comparing both groups. However, when comparing monkeys with proteinuria to those without proteinuria, a statistically significant difference in CK value was observed (P = 0.021). In addition, the CK/AST ratio revealed that 29% of the animals included in this study had values suggesting cardiac infarction. Grossly, cardiac concentric hypertrophy of the left ventricle and small, pitted kidneys were the most common findings. Microscopically, myocardial fibrosis, contraction band necrosis, hypertrophy and hyperplasia of coronary arteries, medium-sized renal arteries, and afferent glomerular arteriolae were the most significant lesions, along with increased mesangial matrix and hypercellularity of glomeruli, Bowman’s capsule, and peritubular space fibroplasia. These findings suggest that CK, AST, and LDH along with urinalysis provide a reliable method for diagnosing cardiomyopathies in the owl monkey. In addition, CK/AST ratio, proteinuria, and the observed histological and ultrastructural changes suggest that Aotus vociferans suffer from arterial hypertension and chronic myocardial infarction.

  15. Signaling pathways regulating murine pancreatic development

    DEFF Research Database (Denmark)

    Serup, Palle

    2012-01-01

    The recent decades have seen a huge expansion in our knowledge about pancreatic development. Numerous lineage-restricted transcription factor genes have been identified and much has been learned about their function. Similarly, numerous signaling pathways important for pancreas development have...... been identified and the specific roles have been investigated by genetic and cell biological methods. The present review presents an overview of the principal signaling pathways involved in regulating murine pancreatic growth, morphogenesis, and cell differentiation....

  16. Kynurenine promotes the goblet cell differentiation of HT-29 colon carcinoma cells by modulating Wnt, Notch and AhR signals.

    Science.gov (United States)

    Park, Joo-Hung; Lee, Jeong-Min; Lee, Eun-Jin; Kim, Da-Jeong; Hwang, Won-Bhin

    2018-04-01

    Various amino acids regulate cell growth and differentiation. In the present study, we examined the ability of HT-29 cells to differentiate into goblet cells in RPMI and DMEM which are largely different in the amounts of numerous amino acids. Most of the HT-29 cells differentiated into goblet cells downregulating the stem cell marker Lgr5 when cultured in DMEM, but remained undifferentiated in RPMI. The goblet cell differentiation in DMEM was inhibited by 1-methyl-tryptophan (1-MT), an inhibitor of indoleamine 2,3 dioxygenase-1 which is the initial enzyme in tryptophan metabolism along the kynurenine (KN) pathway, whereas tryptophan and KN induced goblet cell differentiation in RPMI. The levels of Notch1 and its activation product Notch intracytoplasmic domain in HT-29 cells were lower in DMEM than those in RPMI and were increased by 1-MT in both media. HT-29 cells grown in both media expressed β-catenin at the same level on day 2 when goblet cell differentiation was not observed. β-catenin expression, which was increased by 1-MT in both media, was decreased by KN. DMEM reduced Hes1 expression while enhancing Hath1 expression. Finally, aryl hydrocarbon receptor (AhR) activation moderately induced goblet cell differentiation. Our results suggest that KN promotes goblet cell differentiation by regulating Wnt, Notch, and AhR signals and expression of Hes1 and Hath1.

  17. DMPD: The actions of bacterial DNA on murine macrophages. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 10534106 The actions of bacterial DNA on murine macrophages. Sester DP, Stacey KJ, ... Show The actions of bacterial DNA on murine macrophages. PubmedID 10534106 Title The actions of bacterial DNA on murine macrophage

  18. Effects of x-rays or aseptic inflammatory reaction on the circadian rythm of tyrosine aminotransferase in mouse liver (TAT activity of mouse liver)

    International Nuclear Information System (INIS)

    Jungowska-Klin, B.

    1979-01-01

    The circadian rhythm of tyrosine aminotransferase (TAT) was investigated during 48 hours in the liver of mice subjected to: a/ subcutaneous inflammatory reaction, b/ ionizing radiation. The cyclic changes in the circadian enzyme activity were described with a harmonic function. In relation to the control mice in the experimental mice statistically significant changes were demonstrated in the activity of tyrosine aminotransferase associated with desynchronization of the circadian TAT rhythm, particularly evident in the first hours of the first day of the experiment. The functions of enzyme activity changed in the second 24-hours period showed, both qualitatively and quantitatively, a tendency for a gradual return of normal TAT activity in the 24-hour periods. (author)

  19. Fast-food-based hyper-alimentation can induce rapid and profound elevation of serum alanine aminotransferase in healthy subjects.

    Science.gov (United States)

    Kechagias, S; Ernersson, A; Dahlqvist, O; Lundberg, P; Lindström, T; Nystrom, F H

    2008-05-01

    To study the effect of fast-food-based hyper-alimentation on liver enzymes and hepatic triglyceride content (HTGC). Prospective interventional study with parallel control group. University Hospital of Linköping, Sweden. 12 healthy men and six healthy women with a mean (SD) age of 26 (6.6) years and a matched control group. Subjects in the intervention group aimed for a body weight increase of 5-15% by eating at least two fast-food-based meals a day with the goal to double the regular caloric intake in combination with adoption of a sedentary lifestyle for 4 weeks. Weekly changes of serum aminotransferases and HTGC measured by proton nuclear magnetic resonance spectroscopy at baseline and after the intervention. Subjects in the intervention group increased from 67.6 (9.1) kg to 74.0 (11) kg in weight (p19 U/l, men >30 U/l) during the intervention. Sugar (mono- and disaccharides) intake during week 3 correlated with the maximal ALT/baseline ALT ratio (r = 0.62, p = 0.006). HTGC increased from 1.1 (1.9)% to 2.8 (4.8)%, although this was not related to the increase in ALT levels. ALT levels were unchanged in controls. Hyper-alimentation per se can induce profound ALT elevations in less than 4 weeks. Our study clearly shows that in the evaluation of subjects with elevated ALT the medical history should include not only questions about alcohol intake but also explore whether recent excessive food intake has occurred.

  20. Pre-steady-state kinetics of Escherichia coli aspartate aminotransferase catalyzed reactions and thermodynamic aspects of its substrate specificity

    International Nuclear Information System (INIS)

    Kuramitsu, Seiki; Hiromi, Keitaro; Hayashi, Hideyuki; Morino, Yoshimasa; Kagamiyama, Hiroyuki

    1990-01-01

    The four half-transamination reactions [the pyridoxal form of Escherichia coli aspartate aminotransferase (AspAT) with aspartate or glutamate and the pyridoxamine form of the enzyme with oxalacetate or 2-oxoglutarate] were followed in a stopped-flow spectrometer by monitoring the absorbance change at either 333 or 358 nm. The reaction progress curves in all cases gave fits to a monophasic exponential process. Kinetic analyses of these reactions showed that each half-reaction is composed of the following three processes: (1) the rapid binding of an amino acid substrate to the pyridoxal form of the enzyme; (2) the rapid binding of the corresponding keto acid to the pyridoxamine form of the enzyme; (3) the rate-determining interconversion between the two complexes. This mechanism was supported by the findings that the equilibrium constants for half- and overall-transamination reactions and the steady-state kinetic constants agreed well with the predicted values on the basis of the above mechanism using pre-steady-state kinetic parameters. The significant primary kinetic isotope effect observed in the reaction with deuterated amino acid suggests that the withdrawal of the α-proton of the substrates is rate determining. The pyridoxal form of E. coli AspAT reacted with a variety of amino acids as substrates. The substrate specificity of the E. coli enzyme was much broader than that of pig isoenzymes, reflecting some subtle but distinct difference in microenvironment accommodating the side chain of the substrate between e. coli and mammalian AspATs

  1. Expression of Mitochondrial Branched-Chain Aminotransferase and α-Keto-Acid Dehydrogenase in Rat Brain: Implications for Neurotransmitter Metabolism

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    Jeffrey Thomas Cole

    2012-05-01

    Full Text Available In the brain, metabolism of the essential branched chain amino acids (BCAAs leucine, isoleucine and valine, is regulated in part by protein synthesis requirements. Excess BCAAs are catabolized or excreted. The first step in BCAA catabolism is catalyzed by the branched chain aminotransferase (BCAT isozymes, mitochondrial BCATm and cytosolic BCATc. A product of this reaction, glutamate, is the major excitatory neurotransmitter and precursor of the major inhibitory neurotransmitter -aminobutyric acid (GABA. The BCATs are thought to participate in an α-keto-acid nitrogen shuttle that provides nitrogen for synthesis of glutamate from -ketoglutarate. The branched-chain α-keto acid dehydrogenase enzyme complex (BCKDC catalyzes the second and first irreversible step in BCAA metabolism, which is oxidative decarboxylation of the branched-chain α-keto acid (BCKA products of the BCAT reaction. Maple Syrup Urine Disease (MSUD results from genetic defects in BCKDC, which leads to accumulation of toxic levels of BCAAs and BCKAs that result in brain swelling. Immunolocalization of BCATm and BCKDC in rats revealed that BCATm is present in astrocytes in white matter and in neuropil, while BCKDC is expressed only in neurons. BCATm appears uniformly distributed in astrocyte cell bodies throughout the brain. The segregation of BCATm to astrocytes and BCKDC to neurons provides further support for the existence of a BCAA-dependent glial-neuronal nitrogen shuttle since the data show that BCKAs produced by glial BCATm must be exported to neurons. Additionally, the neuronal localization of BCKDC suggests that MSUD is a neuronal defect involving insufficient oxidation of BCKAs, with secondary effects extending beyond the neuron.

  2. Expression of mitochondrial branched-chain aminotransferase and α-keto-acid dehydrogenase in rat brain: implications for neurotransmitter metabolism

    Science.gov (United States)

    Cole, Jeffrey T.; Sweatt, Andrew J.; Hutson, Susan M.

    2012-01-01

    In the brain, metabolism of the essential branched chain amino acids (BCAAs) leucine, isoleucine, and valine, is regulated in part by protein synthesis requirements. Excess BCAAs are catabolized or excreted. The first step in BCAA catabolism is catalyzed by the branched chain aminotransferase (BCAT) isozymes, mitochondrial BCATm and cytosolic BCATc. A product of this reaction, glutamate, is the major excitatory neurotransmitter and precursor of the major inhibitory neurotransmitter γ-aminobutyric acid (GABA). The BCATs are thought to participate in a α-keto-acid nitrogen shuttle that provides nitrogen for synthesis of glutamate from α-ketoglutarate. The branched-chain α-keto acid dehydrogenase enzyme complex (BCKDC) catalyzes the second, irreversible step in BCAA metabolism, which is oxidative decarboxylation of the branched-chain α-keto acid (BCKA) products of the BCAT reaction. Maple Syrup Urine Disease (MSUD) results from genetic defects in BCKDC, which leads to accumulation of toxic levels of BCAAs and BCKAs that result in brain swelling. Immunolocalization of BCATm and BCKDC in rats revealed that BCATm is present in astrocytes in white matter and in neuropil, while BCKDC is expressed only in neurons. BCATm appears uniformly distributed in astrocyte cell bodies throughout the brain. The segregation of BCATm to astrocytes and BCKDC to neurons provides further support for the existence of a BCAA-dependent glial-neuronal nitrogen shuttle since the data show that BCKAs produced by glial BCATm must be exported to neurons. Additionally, the neuronal localization of BCKDC suggests that MSUD is a neuronal defect involving insufficient oxidation of BCKAs, with secondary effects extending beyond the neuron. PMID:22654736

  3. Complex association of serum alanine aminotransferase with the risk of future cardiovascular disease in type 2 diabetes.

    Science.gov (United States)

    Afarideh, Mohsen; Aryan, Zahra; Ghajar, Alireza; Noshad, Sina; Nakhjavani, Manouchehr; Baber, Usman; Mechanick, Jeffrey I; Esteghamati, Alireza

    2016-11-01

    We aimed to determine the prospective association between baseline serum levels of alanine aminotransferase (ALT) and the incident cardiovascular disease (CVD) in people with type 2 diabetes. In an open cohort setting, people with type 2 diabetes were followed for their first ever CVD presentation from 1995 to 2015. Statistical methods included Cox regression analysis for reporting of hazard ratios (HRs), artificial neural network modelings, and risk reclassification analyses. We found a nearly constant CVD hazard with baseline serum ALT levels below the 30 IU/L mark, whereas baseline serum ALT levels ≥ 30 IU/L remained an independent predictor of lower CVD rates in patients with type 2 diabetes in the final multivariate Cox proportional hazards regression model (HR: 0.204, 95%CI [0.060-0.689], p for trend value = 0.006). Age, male gender and fasting plasma insulin levels independently predicted baseline serum ALT ≥ 30 IU/L among the population cohort. Augmentation of serum ALT into the weighted Framingham risk score resulted in a considerable net reclassification improvement (NRI) of coronary heart disease (CHD) risk prediction in the study population (NRI = 9.05% (8.01%-10.22%), p value < 0.05). Serum ALT could successfully reclassify about 9% of the population with type 2 diabetes across the CHD-affected and CHD-free categories. Overall, our findings demonstrate a complex and nonlinear relationship for the risk of future CVD by baseline serum ALT levels in patients with type 2 diabetes. Further studies are warranted to confirm whether this complex association could be translated into a clearly visible U or J-shaped figure. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  4. Peroxisomal alanine: glyoxylate aminotransferase AGT1 is indispensable for appressorium function of the rice blast pathogen, Magnaporthe oryzae.

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    Vijai Bhadauria

    Full Text Available The role of β-oxidation and the glyoxylate cycle in fungal pathogenesis is well documented. However, an ambiguity still remains over their interaction in peroxisomes to facilitate fungal pathogenicity and virulence. In this report, we characterize a gene encoding an alanine, glyoxylate aminotransferase 1 (AGT1 in Magnaporthe oryzae, the causative agent of rice blast disease, and demonstrate that AGT1 is required for pathogenicity of M. oryzae. Targeted deletion of AGT1 resulted in the failure of penetration via appressoria; therefore, mutants lacking the gene were unable to induce blast symptoms on the hosts rice and barley. This penetration failure may be associated with a disruption in lipid mobilization during conidial germination as turgor generation in the appressorium requires mobilization of lipid reserves from the conidium. Analysis of enhanced green fluorescent protein expression using the transcriptional and translational fusion with the AGT1 promoter and open reading frame, respectively, revealed that AGT1 expressed constitutively in all in vitro grown cell types and during in planta colonization, and localized in peroxisomes. Peroxisomal localization was further confirmed by colocalization with red fluorescent protein fused with the peroxisomal targeting signal 1. Surprisingly, conidia produced by the Δagt1 mutant were unable to form appressoria on artificial inductive surfaces, even after prolonged incubation. When supplemented with nicotinamide adenine dinucleotide (NAD(++pyruvate, appressorium formation was restored on an artificial inductive surface. Taken together, our data indicate that AGT1-dependent pyruvate formation by transferring an amino group of alanine to glyoxylate, an intermediate of the glyoxylate cycle is required for lipid mobilization and utilization. This pyruvate can be converted to non-fermentable carbon sources, which may require reoxidation of NADH generated by the β-oxidation of fatty acids to NAD(+ in

  5. Role of arginine-292 in the substrate specificity of aspartate aminotransferase as examined by site-directed mutagenesis

    International Nuclear Information System (INIS)

    Cronin, C.N.; Kirsch, J.F.

    1988-01-01

    X-ray crystallographic data have implicated Arg-292 as the residue responsible for the preferred side-chain substrate specificity of asparate aminotransferase. It forms a salt bridge with the β or γ carboxylate group of the substrate. In order to test this proposal and, in addition, to attempt to reverse the substrate charge specificity of this enzyme, Arg-292 has been converted to Asp-292 by site-directed mutagenesis. The activity k/sub cat//K/sub M/) of the mutant enzyme, R292D, toward the natural anionic substrates L-aspartate, L-glutamate, and α-ketoglutarate is depressed by over 5 orders of magnitude, whereas the activity toward the keto acid pyruvate and a number of aromatic and other neutral amino acids is reduced by only 2-9-fold. These results confirm the proposal that Arg-292 is critical for the rapid turnover of substrates bearing anionic side chains and show further that, apart from the desired alteration no major perturbations of the remainder of the molecule have been made. The activity of R292D toward the cationic amino acids L-arginine, L-lysine, and L-ornithine is increased by 9-16-fold over that of wild type and the ratio (k/sub cat//K/sub M/)/sub cationic//(k/sub cat//K/sub M/)/sub anionic/ is in the range 2-40-fold for R292D, whereas this ratio has a range of [(0.3-6) x 10 -6 ]-fold for wild type. Thus, the mutation has produced an inversion of the substrate charge specificity. Possible explanations for the less-than-expected reactivity of R292D with arginine are discussed

  6. Serum alanine aminotransferase predicts interventricular septum thickness and left ventricular mass in patients with nonalcoholic fatty liver disease.

    Science.gov (United States)

    Ybarra, Juan; Fernández, Sandra; Sánchez-Hernández, Joan; Romeo, June H; Ballesta-Lopez, Carlos; Guell, Javier; Mearin, Fermin

    2014-06-01

    Alanine aminotransferase (ALT) is a marker of nonalcoholic fatty liver disease (NAFLD) and predicts type 2 diabetes mellitus (DM2) as well as coronary events independently of traditional risk factors and the features of the metabolic syndrome. The extent to which interventricular septum thickness (IVS) and left ventricular mass (LVM) are associated with ALT levels in cohorts of individuals with body weights ranging from overweight to morbid obesity and NAFLD remains still unknown. This was a cross-sectional pilot study involving 151 young White participants with liver ultrasound-proven NAFLD. Standard echocardiograms were used to define LVM, IVS, and left ventricle diastolic function [mitral inflow velocity pattern (E/A ratio) and mitral annulus velocity by tissue Doppler imaging (Em/Am ratio)]. Participants were classified according to ALT quartiles: p25, p50, p75, and p100. The study included 36 men and 115 women with an age of 38.4 ± 0.7 years and BMI of 43.9 ± 0.6 kg/m2. p100 participants disclosed significantly higher homeostasis model assessment (P=0.003), DM2 (P=0.002), and hypertension (P=0.01) prevalence, whereas LVM, IVS, E/A, and Em/Am ratios were significantly higher in this group when compared with their p25 peers (PDM2. ALT levels predict both IVS and LVM in NAFLD individuals irrespective of their BMI, DM2, hypertension, age, and sex. ALT levels behave as a surrogate marker of left ventricular hypertrophy in overweight and/or obese NAFLD patients. Hence, it seems worth obtaining cardiac ultrasounds in NAFLD patients with elevated ALT levels.

  7. Saccharomyces cerevisiae Bat1 and Bat2 aminotransferases have functionally diverged from the ancestral-like Kluyveromyces lactis orthologous enzyme.

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    Maritrini Colón

    Full Text Available BACKGROUND: Gene duplication is a key evolutionary mechanism providing material for the generation of genes with new or modified functions. The fate of duplicated gene copies has been amply discussed and several models have been put forward to account for duplicate conservation. The specialization model considers that duplication of a bifunctional ancestral gene could result in the preservation of both copies through subfunctionalization, resulting in the distribution of the two ancestral functions between the gene duplicates. Here we investigate whether the presumed bifunctional character displayed by the single branched chain amino acid aminotransferase present in K. lactis has been distributed in the two paralogous genes present in S. cerevisiae, and whether this conservation has impacted S. cerevisiae metabolism. PRINCIPAL FINDINGS: Our results show that the KlBat1 orthologous BCAT is a bifunctional enzyme, which participates in the biosynthesis and catabolism of branched chain aminoacids (BCAAs. This dual role has been distributed in S. cerevisiae Bat1 and Bat2 paralogous proteins, supporting the specialization model posed to explain the evolution of gene duplications. BAT1 is highly expressed under biosynthetic conditions, while BAT2 expression is highest under catabolic conditions. Bat1 and Bat2 differential relocalization has favored their physiological function, since biosynthetic precursors are generated in the mitochondria (Bat1, while catabolic substrates are accumulated in the cytosol (Bat2. Under respiratory conditions, in the presence of ammonium and BCAAs the bat1Δ bat2Δ double mutant shows impaired growth, indicating that Bat1 and Bat2 could play redundant roles. In K. lactis wild type growth is independent of BCAA degradation, since a Klbat1Δ mutant grows under this condition. CONCLUSIONS: Our study shows that BAT1 and BAT2 differential expression and subcellular relocalization has resulted in the distribution of the

  8. Influence of Preoperative Serum Aspartate Aminotransferase (AST Level on the Prognosis of Patients with Non-Small Cell Lung Cancer

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    Shu-Lin Chen

    2016-09-01

    Full Text Available The purpose of this work is to analyze preoperative serum aspartate aminotransferase (AST levels and their effect on the prognosis of patients with non-small cell lung cancer (NSCLC after surgical operation. These analyses were performed retrospectively in patients with NSCLC followed by surgery; participants were recruited between January 2004 and January 2008. All clinical information and laboratory results were collected from medical records. We explored the association between preoperative serum AST and recurrence-free survival (RFS, and the overall survival (OS of NSCLC patients. Kaplan–Meier analysis and Cox multivariate analysis, stratified by the AST median value, were used to evaluate the prognostic effect. A chi-squared test was performed to compare clinical characteristics in different subgroups. A p-value of ≤0.05 was considered to be statistically significant. A total of 231 patients were enrolled. The median RFS and OS were 22 and 59 months, respectively. The AST levels were divided into two groups, using a cut-off value of 19 U/L: High AST (>19 U/L, n = 113 vs. low AST (≤19 U/L, n = 118. Multivariate analysis indicated that preoperative serum AST > 19 U/L (hazard ratio (HR = 0.685, 95% confidence interval (CI: 0.493–0.994, p = 0.046 for RFS, HR = 0.646, 95% CI: 0.438–0.954, p = 0.028 for OS was an independent prognostic factor for both RFS and OS. High preoperative serum AST levels may serve as a valuable marker to predict the prognosis of NSCLC after operation.

  9. Azithromycin prophylaxis and treatment of murine toxoplasmosis.

    Science.gov (United States)

    Tabbara, Khalid F; Hammouda, Ehab; Tawfik, Abdulkader; Al-Omar, Othman M; Abu El-Asrar, Ahmed M

    2005-03-01

    To evaluate the azithromycin effects alone and in combination with other agents in the prophylaxis and treatment of murine toxoplasmosis. A total of 280 BALB/c mice were included, and 2 x 103 Toxoplasma organisms of the RH strain Toxoplasma gondii strain ATCC50174 were given intraperitoneally to each mouse. In experiment one, 40 animals were given azithromycin 200 milligram/kilogram/daily for 3 days starting the day of inoculation, 40 mice were control. In experiment 2, the treatment was started 48 hours after inoculation and given daily for 3 days: one group received azithromycin 200 milligram/kilogram/day, the second group received pyrimethamine 25 milligram/kilogram/day, and the sulfadiazine 100 milligram/kilogram/day. The third group was control. In experiment 3, 7 groups of animals received one of the following (1) none, (2) azithromycin 200 milligram/kilogram/day, (3) pyrimethamine 25 milligram/kilogram/day and sulfadiazine 100 milligram/kilogram/day, (4) azithromycin and sulfadiazine, (5) azithromycin and pyrimethamine, (6) azithromycin with sulfadiazine and pyrimethamine, (7) sulfadiazine alone. Treatment was initiated 72 hours after inoculation for 3 days. The study was conducted at the Animal Care Facility of King Saud University, Riyadh, Kingdom of Saudi Arabia. Animals that received azithromycin simultaneously with inoculation survived, and all control animals died. All animals died in groups receiving single drug therapy. Animals treated with azithromycin and sulfadiazine showed a survival rate of 40%, sulfadiazine and pyrimethamine 40%, or azithromycin with sulfadiazine and pyrimethamine 95% (p<0.0001). Azithromycin alone was found to be effective in the prophylaxis of murine toxoplasmosis. Combination therapy was effective in the treatment of murine toxoplasmosis.

  10. Efficacy of posaconazole in murine experimental sporotrichosis.

    Science.gov (United States)

    Fernández-Silva, Fabiola; Capilla, Javier; Mayayo, Emilio; Guarro, Josep

    2012-05-01

    We developed a murine model of systemic sporotrichosis by using three strains of each of the two commonest species causing sporotrichosis, i.e., Sporothrix schenckii sensu stricto and Sporothrix brasiliensis, in order to evaluate the efficacy of posaconazole (PSC). The drug was administered at a dose of 2.5 or 5 mg/kg of body weight twice a day by gavage, and one group was treated with amphotericin B (AMB) as a control treatment. Posaconazole, especially at 5 mg/kg, showed good efficacy against all the strains tested, regardless of their MICs, as measured by prolonged survival, tissue burden reduction, and histopathology.

  11. Irradiation Design for an Experimental Murine Model

    International Nuclear Information System (INIS)

    Ballesteros-Zebadua, P.; Moreno-Jimenez, S.; Suarez-Campos, J. E.; Celis, M. A.; Larraga-Gutierrez, J. M.; Garcia-Garduno, O. A.; Rubio-Osornio, M. C.; Custodio-Ramirez, V.; Paz, C.

    2010-01-01

    In radiotherapy and stereotactic radiosurgery, small animal experimental models are frequently used, since there are still a lot of unsolved questions about the biological and biochemical effects of ionizing radiation. This work presents a method for small-animal brain radiotherapy compatible with a dedicated 6MV Linac. This rodent model is focused on the research of the inflammatory effects produced by ionizing radiation in the brain. In this work comparisons between Pencil Beam and Monte Carlo techniques, were used in order to evaluate accuracy of the calculated dose using a commercial planning system. Challenges in this murine model are discussed.

  12. Thrombopoietin inhibits murine mast cell differentiation

    Science.gov (United States)

    Martelli, Fabrizio; Ghinassi, Barbara; Lorenzini, Rodolfo; Vannucchi, Alessandro M; Rana, Rosa Alba; Nishikawa, Mitsuo; Partamian, Sandra; Migliaccio, Giovanni; Migliaccio, Anna Rita

    2009-01-01

    We have recently shown that Mpl, the thrombopoietin receptor, is expressed on murine mast cells and on their precursors and that targeted deletion of the Mpl gene increases mast cell differentiation in mice. Here we report that treatment of mice with thrombopoietin, or addition of this growth factor to bone marrow-derived mast cell cultures, severely hampers the generation of mature cells from their precursors by inducing apoptosis. Analysis of the expression profiling of mast cells obtained in the presence of thrombopoietin suggests that thrombopoietin induces apoptosis of mast cells by reducing expression of the transcription factor Mitf and its target anti-apoptotic gene Bcl2. PMID:18276801

  13. Increased levels of IL-6 in the cerebrospinal fluid of patients with chronic schizophrenia — significance for activation of the kynurenine pathway

    Science.gov (United States)

    Schwieler, Lilly; Larsson, Markus K.; Skogh, Elisabeth; Kegel, Magdalena E.; Orhan, Funda; Abdelmoaty, Sally; Finn, Anja; Bhat, Maria; Samuelsson, Martin; Lundberg, Kristina; Dahl, Marja-Liisa; Sellgren, Carl; Schuppe-Koistinen, Ina; Svensson, Camilla I.; Erhardt, Sophie; Engberg, Göran

    2015-01-01

    Background Accumulating evidence indicates that schizophrenia is associated with brain immune activation. While a number of reports suggest increased cytokine levels in patients with schizophrenia, many of these studies have been limited by their focus on peripheral cytokines or confounded by various antipsychotic treatments. Here, well-characterized patients with schizophrenia, all receiving olanzapine treatment, and healthy volunteers were analyzed with regard to cerebrospinal fluid (CSF) levels of cytokines. We correlated the CSF cytokine levels to previously analyzed metabolites of the kynurenine (KYN) pathway. Methods We analyzed the CSF from patients and controls using electrochemiluminescence detection with regard to cytokines. Cell culture media from human cortical astrocytes were analyzed for KYN and kynurenic acid (KYNA) using high-pressure liquid chromatography or liquid chromatography/mass spectrometry. Results We included 23 patients and 37 controls in our study. Patients with schizophrenia had increased CSF levels of interleukin (IL)-6 compared with healthy volunteers. In patients, we also observed a positive correlation between IL-6 and the tryptophan:KYNA ratio, indicating that IL-6 activates the KYN pathway. In line with this, application of IL-6 to cultured human astrocytes increased cell medium concentration of KYNA. Limitations The CSF samples had been frozen and thawed twice before analysis of cytokines. Median age differed between patients and controls. When appropriate, all present analyses were adjusted for age. Conclusion We have shown that IL-6, KYN and KYNA are elevated in patients with chronic schizophrenia, strengthening the idea of brain immune activation in patients with this disease. Our concurrent cell culture and clinical findings suggest that IL-6 induces the KYN pathway, leading to increased production of the N-methyl-d-aspartate receptor antagonist KYNA in patients with schizophrenia. PMID:25455350

  14. A murine model of type 2 autoimmune hepatitis: Xenoimmunization with human antigens.

    Science.gov (United States)

    Lapierre, Pascal; Djilali-Saiah, Idriss; Vitozzi, Susana; Alvarez, Fernando

    2004-04-01

    Autoimmune hepatitis (AIH) is characterized by an immune-mediated injury of the hepatic parenchyma of unknown pathogenesis. Type 2 AIH is identified by the presence of anti-liver-kidney microsomes type 1 (anti-LKM1) and anti-liver cytosol type 1 (anti-LC1) autoantibodies. The current study shows that a murine model of AIH can be generated by DNA immunization against type 2 AIH self-antigens (P450 2D6 and formiminotransferase-cyclodeaminase). A pCMV plasmid containing the N-terminal region of mouse CTLA-4 and the antigenic region of human CYP2D6 (672-1,377 bp) and human formiminotransferase cyclodeaminase (FTCD; 1,232-1,668 bp) was used for DNA immunization of C57BL/6 female mice. Immunized mice showed elevated levels of alanine aminotransferase (ALT), with peaks at 4 and 7 months postinjection. Periportal, portal, and intralobular liver inflammatory infiltrates were observed at histology. Mainly CD4+ lymphocytes, but also CD8+ and B lymphocytes, were found in the liver. Cytotoxic-specific T cells were found in both the liver and spleen of these animals. Mice developed anti-LKM1 and anti-LC1 antibodies of immunoglobulin G2 (IgG2) subclass, against specific mouse autoantigens. The ALT levels correlated with both the presence of anti-LKM1/anti-LC1 antibodies and the presence of liver necroinflammation. In conclusion, in mice, DNA immunization against human autoantigens breaks tolerance and induces an autoimmune liver disease. Molecular mimicry between foreign and self-antigens explains the liver injury. This model of AIH resembles human type 2 AIH and will be helpful for the study of its pathogenesis.

  15. Elevated alanine aminotransferase is strongly associated with incident metabolic syndrome: a meta-analysis of prospective studies.

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    Zhengtao Liu

    Full Text Available BACKGROUND: The incidence of metabolic syndrome (MetS is rapidly increasing worldwide and associated with alanine aminotransferase (ALT activity. However, the impact of ALT activity on MetS incidence is inconsistent in published literature. We therefore estimated the association between elevated ALT activity and incident MetS through a meta-analysis of prospective cohort studies. METHODS/PRINCIPAL FINDINGS: All published prospective cohort studies on the association between elevated ALT activity and incident MetS were retrieved from Pubmed, Embase, and the Institute for Scientific Information (ISI. In all, seven prospective cohort studies, with 31545 participants and 2873 cases of incident MetS were recruited. If there was insignificant heterogeneity (P-value>0.05 and I(2<50%, the fixed-effect model was used to calculate the pooled relative risks (RRs of incident MetS induced by raised ALT. Otherwise, the random-effect model was used. The calculated RR was 1.81 (95% confidence interval [CI]: 1.49-2.14 when the incidence of MetS was compared between the highest versus the lowest classification of ALT activities. The pooled RR was 1.13 (95% CI: 1.11-1.16 in dose-response analysis with 5 units per liter (U/l of ALT increment. Subgroup analysis suggested that gender disparity might be the main origin of heterogeneity in overall analysis (P = 0.007 between RRs of gender-specific subgroups evaluated with 5 U/l increments of ALT. Women had a higher dose-response risk of MetS incidence (1.38, 95% CI: 1.20-1.55 than men. Furthermore, sensitivity analysis confirmed the stability of results. No publication bias was found in our meta-analysis. CONCLUSIONS/SIGNIFICANCE: Current evidence from prospective studies supports the association between ALT elevation and increasing MetS incidence. This association is closer and more consistent in female population. Further studies are needed to confirm this association and to investigate the potential mechanism of

  16. Sex-Specific Association between Metabolic Abnormalities and Elevated Alanine Aminotransferase Levels in a Military Cohort: The CHIEF Study

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    Kai-Wen Chen

    2018-03-01

    Full Text Available The association of metabolic syndrome (MetS components with elevated serum alanine aminotransferase (ALT levels, a marker of hepatic injury, may differ between men and women. However, the sex-specific association in a military young population which has a low prevalence of MetS was unclear. We conducted a cross-sectional examination in 6738 men and 766 women, aged 18–50 years, from the cardiorespiratory fitness study in armed forces (CHIEF in eastern Taiwan. The components of MetS were defined according to the updated International Diabetes Federation (IDF ethnic criteria for Asians. Elevated ALT levels were defined as ≥40 U/L for both sexes and ≥30 U/L for women alternatively. Multivariate logistic regression analysis was performed to determine the sex-specific association between MetS components and elevated ALT. The prevalence of MetS and elevated ALT in men were 11.9% and 12.7% respectively, and in women were 3.5%, and 3.8% respectively. In men, high-density lipoprotein < 40 mg/dL, blood pressures ≥ 130/85 mmHg, serum triglycerides ≥ 150 mg/dL, and waist size ≥ 90 cm were associated with elevated ALT (odds ratios (OR and 95% confidence intervals: 1.59 (1.34–1.90, 1.40 (1.19–1.65, 2.00 (1.68–2.39, and 1.68 (1.38–2.04; all p < 0.001; whereas in women, only fasting plasma glucose ≥ 100 mg/dL was associated with elevated ALT ≥ 40 U/L (OR: 7.59 (2.35–24.51, p = 0.001 and ALT ≥ 30 U/L (2.67 (0.89–7.95, p = 0.08. Our findings suggest that the relationship between metabolic abnormalities and elevated ALT may differ by sex, possibly due to the MetS more prevalent in young adult men than in women.

  17. Effect of mammals’ excretory function on aspartate aminotransferase activity in Glechoma hederacea leaves in conditions of Cd pollution

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    O. M. Vasilyuk

    2014-07-01

    Full Text Available The paper includes analysis of research of Cd impact on the activity of the enzyme of aspartate aminotransferase (AST nitrogen metabolism and the content of water-soluble protein fraction (albumin in Glechoma hederacea L. leaves, which dominated in the research area (in natural floodplain oak forest with Stellaria holostea L.. Cd was introduced in the form of salts of Cd(NO32 in the range of concentrations of: 0.25, 1.25, 2.5 g/m2, equivalent to the inclusion of Cd in 1, 5, 10 doses of MAC. Increase (P < 0.05 in the activity of AST 2.6–3.0 times (with adding Cd salts at a dose of 1 and 5 МAС and albumin content by 37% (with adding Cd salts at a dose of 10 МAС compared to control (the area without Cd pollution and excretory activity of mammals was shown. Using of excreta of some representatives of mammals (for example, Capreolus capreolus L. contributed to reduction of Cd toxic effects and restoring of the functional metabolic activity of AST by 23% (with Cd 1 МAС and by 34% (Cd 5 МAС. It is the evidence of protective function of mammals and their normalization effect at the above concentrations of Cd. Whereas the adding of Cd salts at a dose of 10 МAС led to 3 times’ inhibition of AST activity, the toxic effect of metal by excretory function of mammals was not reduced. Observations revealed the albumin content normalization by 22% in the presence of Cd 1MAC respectively (with the introduction of C. capreolus excreta and to the control level (the area without Cd pollution and excretory activity of mammals with the excreta of Sus scrofa L. in the setting of Cd 10 MAC. It proves the need to use the different mammal species for integrated and comprehensive normalization of ecosystems under conditions of uncontrolled anthropogenic pollution.

  18. [Virulence of Sporothrix globosa in murine models].

    Science.gov (United States)

    Cruz Choappa, Rodrigo; Pérez Gaete, Salomón; Rodríguez Badilla, Valentina; Vieille Oyarzo, Peggy; Opazo Sanchez, Héctor

    The sporothricosis disease is an infection caused by species included in Sporothrix schenkii complex. Verify the virulence of a strain of S. globosa using two different concentrations of inoculum by intraperitoneally and subcutaneously, into a mouse model. Nonrandomized pilot study, in murine inoculated with a strain of S. globosa (CBS 14.076M) by intraperitoneally and subcutaneously with inoculum concentrations of 0.5 and 4 McFarland. For this purpose 18 rodents CF-1 (ISP, Santiago, Chile) were used. The studied strain did not induce illness or injury on animals, they all survived and neither the tissue culture nor the histopathological analysis showed fungal growth or suggestive infection by organ abnormalities. The S. globosa strain did not present any virulence enough to cause disease at 0.5 and 4.0 McFarland concentration inoculum when inoculated in both intraperitoneally and subcutaneously, in murine models. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  19. Lactoferrin dampens high-fructose corn syrup-induced hepatic manifestations of the metabolic syndrome in a murine model.

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    Yi-Chieh Li

    Full Text Available Hepatic manifestations of the metabolic syndrome are related obesity, type 2 diabetes/insulin resistance and non-alcoholic fatty liver disease. Here we investigated how the anti-inflammatory properties of lactoferrin can protect against the onset of hepatic manifestations of the metabolic syndrome by using a murine model administered with high-fructose corn syrup. Our results show that a high-fructose diet stimulates intestinal bacterial overgrowth and increases intestinal permeability, leading to the introduction of endotoxin into blood circulation and liver. Immunohistochemical staining of Toll-like receptor-4 and thymic stromal lymphopoietin indicated that lactoferrin can modulate lipopolysaccharide-mediated inflammatory cascade. The important regulatory roles are played by adipokines including interleukin-1β, interleukin-6, tumor necrosis factor-α, monocyte chemotactic protein-1, and adiponectin, ultimately reducing hepatitis and decreasing serum alanine aminotransferase release. These beneficial effects of lactoferrin related to the downregulation of the lipopolysaccharide-induced inflammatory cascade in the liver. Furthermore, lactoferrin reduced serum and hepatic triglycerides to prevent lipid accumulation in the liver, and reduced lipid peroxidation, resulting in 4-hydroxynonenal accumulation. Lactoferrin reduced oral glucose tolerance test and homeostasis model assessment-insulin resistance. Lactoferrin administration thus significantly lowered liver weight, resulting from a decrease in the triglyceride and cholesterol synthesis that activates hepatic steatosis. Taken together, these results suggest that lactoferrin protected against high-fructose corn syrup induced hepatic manifestations of the metabolic syndrome.

  20. Lactoferrin dampens high-fructose corn syrup-induced hepatic manifestations of the metabolic syndrome in a murine model.

    Science.gov (United States)

    Li, Yi-Chieh; Hsieh, Chang-Chi

    2014-01-01

    Hepatic manifestations of the metabolic syndrome are related obesity, type 2 diabetes/insulin resistance and non-alcoholic fatty liver disease. Here we investigated how the anti-inflammatory properties of lactoferrin can protect against the onset of hepatic manifestations of the metabolic syndrome by using a murine model administered with high-fructose corn syrup. Our results show that a high-fructose diet stimulates intestinal bacterial overgrowth and increases intestinal permeability, leading to the introduction of endotoxin into blood circulation and liver. Immunohistochemical staining of Toll-like receptor-4 and thymic stromal lymphopoietin indicated that lactoferrin can modulate lipopolysaccharide-mediated inflammatory cascade. The important regulatory roles are played by adipokines including interleukin-1β, interleukin-6, tumor necrosis factor-α, monocyte chemotactic protein-1, and adiponectin, ultimately reducing hepatitis and decreasing serum alanine aminotransferase release. These beneficial effects of lactoferrin related to the downregulation of the lipopolysaccharide-induced inflammatory cascade in the liver. Furthermore, lactoferrin reduced serum and hepatic triglycerides to prevent lipid accumulation in the liver, and reduced lipid peroxidation, resulting in 4-hydroxynonenal accumulation. Lactoferrin reduced oral glucose tolerance test and homeostasis model assessment-insulin resistance. Lactoferrin administration thus significantly lowered liver weight, resulting from a decrease in the triglyceride and cholesterol synthesis that activates hepatic steatosis. Taken together, these results suggest that lactoferrin protected against high-fructose corn syrup induced hepatic manifestations of the metabolic syndrome.

  1. Clearance of 131I-labeled murine monoclonal antibody from patients' blood by intravenous human anti-murine immunoglobulin antibody

    International Nuclear Information System (INIS)

    Stewart, J.S.; Sivolapenko, G.B.; Hird, V.; Davies, K.A.; Walport, M.; Ritter, M.A.; Epenetos, A.A.

    1990-01-01

    Five patients treated with intraperitoneal 131I-labeled mouse monoclonal antibody for ovarian cancer also received i.v. exogenous polyclonal human anti-murine immunoglobulin antibody. The pharmacokinetics of 131I-labeled monoclonal antibody in these patients were compared with those of 28 other patients receiving i.p.-radiolabeled monoclonal antibody for the first time without exogenous human anti-murine immunoglobulin, and who had no preexisting endogenous human anti-murine immunoglobulin antibody. Patients receiving i.v. human anti-murine immunoglobulin antibody demonstrated a rapid clearance of 131I-labeled monoclonal antibody from their circulation. The (mean) maximum 131I blood content was 11.4% of the injected activity in patients receiving human anti-murine immunoglobulin antibody compared to 23.3% in patients not given human anti-murine immunoglobulin antibody. Intravenous human anti-murine immunoglobulin antibody decreased the radiation dose to bone marrow (from 131I-labeled monoclonal antibody in the vascular compartment) 4-fold. Following the injection of human anti-murine immunoglobulin antibody, 131I-monoclonal/human anti-murine immunoglobulin antibody immune complexes were rapidly transported to the liver. Antibody dehalogenation in the liver was rapid, with 87% of the injected 131I excreted in 5 days. Despite the efficient hepatic uptake of immune complexes, dehalogenation of monoclonal antibody was so rapid that the radiation dose to liver parenchyma from circulating 131I was decreased 4-fold rather than increased. All patients developed endogenous human anti-murine immunoglobulin antibody 2 to 3 weeks after treatment

  2. Anatomy and Histology of the Human and Murine Prostate.

    Science.gov (United States)

    Ittmann, Michael

    2018-05-01

    The human and murine prostate glands have similar functional roles in the generation of seminal fluid to assist in reproduction. There are significant differences in the anatomy and histology of murine and human prostate and knowledge of the normal anatomy and histology of the murine prostate is essential to interpreting changes in genetically engineered mouse models. In this review, the normal anatomy and histology of both human and mouse prostate will be described. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

  3. Murine leukemia viruses: objects and organisms.

    Science.gov (United States)

    Rein, Alan

    2011-01-01

    Murine leukemia viruses (MLVs) are among the simplest retroviruses. Prototypical gammaretroviruses encode only the three polyproteins that will be used in the assembly of progeny virus particles. These are the Gag polyprotein, which is the structural protein of a retrovirus particle, the Pol protein, comprising the three retroviral enzymes-protease, which catalyzes the maturation of the particle, reverse transcriptase, which copies the viral RNA into DNA upon infection of a new host cell, and integrase, which inserts the DNA into the chromosomal DNA of the host cell, and the Env polyprotein, which induces the fusion of the viral membrane with that of the new host cell, initiating infection. In general, a productive MLV infection has no obvious effect upon host cells. Although gammaretroviral structure and replication follow the same broad outlines as those of other retroviruses, we point out a number of significant differences between different retroviral genera.

  4. Proliferative capacity of murine hematopoietic stem cells

    International Nuclear Information System (INIS)

    Hellman, S.; Botnick, L.E.; Hannon, E.C.; Vigneulle, R.M.

    1978-01-01

    The present study demonstrates a decrease in self-renewal capacity with serial transfer of murine hematopoietic stem cells. Production of differentiated cell progeny is maintained longer than stem cell self-renewal. In normal animals the capacity for self-renewal is not decreased with increasing donor age. The stem cell compartment in normal animals, both young and old, appears to be proliferatively quiescent. After apparent recovery from the alkylating agent busulfan, the probability of stem cell self-renewal is decreased, there is a permanent defect in the capacity of the bone marrow for serial transplantation, and the stem cells are proliferatively active. These findings support a model of the hematopoietic stem cell compartment as a continuum of cells with decreasing capacities for self-renewal, increasing likelihood for differentiation, and increasing proliferative activity. Cells progress in the continuum in one direction and such progression is not reversible

  5. Murine model of long term obstructive jaundice

    Science.gov (United States)

    Aoki, Hiroaki; Aoki, Masayo; Yang, Jing; Katsuta, Eriko; Mukhopadhyay, Partha; Ramanathan, Rajesh; Woelfel, Ingrid A.; Wang, Xuan; Spiegel, Sarah; Zhou, Huiping; Takabe, Kazuaki

    2016-01-01

    Background With the recent emergence of conjugated bile acids as signaling molecules in cancer, a murine model of obstructive jaundice by cholestasis with long-term survival is in need. Here, we investigated the characteristics of 3 murine models of obstructive jaundice. Methods C57BL/6J mice were used for total ligation of the common bile duct (tCL), partial common bile duct ligation (pCL), and ligation of left and median hepatic bile duct with gallbladder removal (LMHL) models. Survival was assessed by Kaplan-Meier method. Fibrotic change was determined by Masson-Trichrome staining and Collagen expression. Results 70% (7/10) of tCL mice died by Day 7, whereas majority 67% (10/15) of pCL mice survived with loss of jaundice. 19% (3/16) of LMHL mice died; however, jaundice continued beyond Day 14, with survival of more than a month. Compensatory enlargement of the right lobe was observed in both pCL and LMHL models. The pCL model demonstrated acute inflammation due to obstructive jaundice 3 days after ligation but jaundice rapidly decreased by Day 7. The LHML group developed portal hypertension as well as severe fibrosis by Day 14 in addition to prolonged jaundice. Conclusion The standard tCL model is too unstable with high mortality for long-term studies. pCL may be an appropriate model for acute inflammation with obstructive jaundice but long term survivors are no longer jaundiced. The LHML model was identified to be the most feasible model to study the effect of long-term obstructive jaundice. PMID:27916350

  6. Formation and maturation of the murine meniscus.

    Science.gov (United States)

    Gamer, Laura W; Xiang, Lin; Rosen, Vicki

    2017-08-01

    Meniscal injuries are commonplace, but current surgical repair procedures do not prevent degenerative joint changes that occur after meniscal injury and often lead to osteoarthritis. Successful tissue regeneration in adults often recapitulates events that occur during embryogenesis, suggesting that understanding the regulatory pathways controlling these early processes may provide clues for developing strategies for tissue repair. While the mouse is now widely used to study joint diseases, detailed knowledge of the basic biology of murine meniscus is not readily available. Here, we examine meniscal morphogenesis in mice from embryonic day 13.5 (E13.5) to 6 months of age using histology, in situ hybridization, and immunohistochemistry. We find that the meniscus is a morphologically distinct structure at E16 when it begins to regionalize. At birth, the meniscus has a distinguishable inner, avascular, round chondrocyte cell region, an outer, vascularized, fibroblast cell region, and a surface superficial zone. Maturation begins at 2 weeks of age when the meniscus expresses type I collagen, type II collagen, type X collagen, and MMP-13 in specific patterns. By 4 weeks of age, small areas of ossification are detected in the anterior meniscal horn, a common feature seen in rodents. Maturation appears complete at 8 weeks of age, when the meniscus resembles the adult structure complete with ossifying tissue that contains bone marrow like areas. Our results provide, the first systematic study of mouse meniscal development and will be a valuable tool for analyzing murine models of knee joint formation and disease. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1683-1689, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  7. Kynurenine 3-Monooxygenase Gene Associated With Nicotine Initiation and Addiction: Analysis of Novel Regulatory Features at 5′ and 3′-Regions

    Directory of Open Access Journals (Sweden)

    Hassan A. Aziz

    2018-06-01

    Full Text Available Tobacco smoking is widespread behavior in Qatar and worldwide and is considered one of the major preventable causes of ill health and death. Nicotine is part of tobacco smoke that causes numerous health risks and is incredibly addictive; it binds to the α7 nicotinic acetylcholine receptor (α7nAChR in the brain. Recent studies showed α7nAChR involvement in the initiation and addiction of smoking. Kynurenic acid (KA, a significant tryptophan metabolite, is an antagonist of α7nAChR. Inhibition of kynurenine 3-monooxygenase enzyme encoded by KMO enhances the KA levels. Modulating KMO gene expression could be a useful tactic for the treatment of tobacco initiation and dependence. Since KMO regulation is still poorly understood, we aimed to investigate the 5′ and 3′-regulatory factors of KMO gene to advance our knowledge to modulate KMO gene expression. In this study, bioinformatics methods were used to identify the regulatory sequences associated with expression of KMO. The displayed differential expression of KMO mRNA in the same tissue and different tissues suggested the specific usage of the KMO multiple alternative promoters. Eleven KMO alternative promoters identified at 5′-regulatory region contain TATA-Box, lack CpG Island (CGI and showed dinucleotide base-stacking energy values specific to transcription factor binding sites (TFBSs. The structural features of regulatory sequences can influence the transcription process and cell type-specific expression. The uncharacterized LOC105373233 locus coding for non-coding RNA (ncRNA located on the reverse strand in a convergent manner at the 3′-side of KMO locus. The two genes likely expressed by a promoter that lacks TATA-Box harbor CGI and two TFBSs linked to the bidirectional transcription, the NRF1, and ZNF14 motifs. We identified two types of microRNA (miR in the uncharacterized LOC105373233 ncRNA, which are like hsa-miR-5096 and hsa-miR-1285-3p and can target the miR recognition

  8. Characterization of a bordetella pertussis diaminopimelate (DAP) biosynthesis locus identifies dapC, a novel gene coding for an N-succinyl-L,L-DAP aminotransferase.

    Science.gov (United States)

    Fuchs, T M; Schneider, B; Krumbach, K; Eggeling, L; Gross, R

    2000-07-01

    The functional complementation of two Escherichia coli strains defective in the succinylase pathway of meso-diaminopimelate (meso-DAP) biosynthesis with a Bordetella pertussis gene library resulted in the isolation of a putative dap operon containing three open reading frames (ORFs). In line with the successful complementation of the E. coli dapD and dapE mutants, the deduced amino acid sequences of two ORFs revealed significant sequence similarities with the DapD and DapE proteins of E. coli and many other bacteria which exhibit tetrahydrodipicolinate succinylase and N-succinyl-L,L-DAP desuccinylase activity, respectively. The first ORF within the operon showed significant sequence similarities with transaminases and contains the characteristic pyridoxal-5'-phosphate binding motif. Enzymatic studies revealed that this ORF encodes a protein with N-succinyl-L,L-DAP aminotransferase activity converting N-succinyl-2-amino-6-ketopimelate, the product of the succinylase DapD, to N-succinyl-L,L-DAP, the substrate of the desuccinylase DapE. Therefore, this gene appears to encode the DapC protein of B. pertussis. Apart from the pyridoxal-5'-phosphate binding motif, the DapC protein does not show further amino acid sequence similarities with the only other known enzyme with N-succinyl-L,L-DAP aminotransferase activity, ArgD of E. coli.

  9. Murine Ileocolic Bowel Resection with Primary Anastomosis

    Science.gov (United States)

    Perry, Troy; Borowiec, Anna; Dicken, Bryan; Fedorak, Richard; Madsen, Karen

    2014-01-01

    Intestinal resections are frequently required for treatment of diseases involving the gastrointestinal tract, with Crohn’s disease and colon cancer being two common examples. Despite the frequency of these procedures, a significant knowledge gap remains in describing the inherent effects of intestinal resection on host physiology and disease pathophysiology. This article provides detailed instructions for an ileocolic resection with primary end-to-end anastomosis in mice, as well as essential aspects of peri-operative care to maximize post-operative success. When followed closely, this procedure yields a 95% long-term survival rate, no failure to thrive, and minimizes post-operative complications of bowel obstruction and anastomotic leak. The technical challenges of performing the procedure in mice are a barrier to its wide spread use in research. The skills described in this article can be acquired without previous surgical experience. Once mastered, the murine ileocolic resection procedure will provide a reproducible tool for studying the effects of intestinal resection in models of human disease. PMID:25406841

  10. Glycosaminoglycan interactions in murine gammaherpesvirus-68 infection.

    Directory of Open Access Journals (Sweden)

    Laurent Gillet

    2007-04-01

    Full Text Available Glycosaminoglycans (GAGs commonly participate in herpesvirus entry. They are thought to provide a reversible attachment to cells that promotes subsequent receptor binding. Murine gamma-herpesvirus-68 (MHV-68 infection of fibroblasts and epithelial cells is highly GAG-dependent. This is a function of the viral gp150, in that gp150-deficient mutants are much less GAG-dependent than wild-type. Here we show that the major MHV-68 GAG-binding protein is not gp150 but gp70, a product of ORF4. Surprisingly, ORF4-deficient MHV-68 showed normal cell binding and was more sensitive than wild-type to inhibition by soluble heparin rather than less. Thus, the most obvious viral GAG interaction made little direct contribution to infection. Indeed, a large fraction of the virion gp70 had its GAG-binding domain removed by post-translational cleavage. ORF4 may therefore act mainly to absorb soluble GAGs and prevent them from engaging gp150 prematurely. In contrast to gp70, gp150 bound poorly to GAGs, implying that it provides little in the way of adhesion. We hypothesize that it acts instead as a GAG-sensitive switch that selectively activates MHV-68 entry at cell surfaces.

  11. Kynurenine 3-monooxygenase from Pseudomonas fluorescens: substrate-like inhibitors both stimulate flavin reduction and stabilize the flavin-peroxo intermediate yet result in the production of hydrogen peroxide.

    Science.gov (United States)

    Crozier-Reabe, Karen R; Phillips, Robert S; Moran, Graham R

    2008-11-25

    Kynurenine 3-monooxygenase (KMO) is a flavin-dependent hydroxylase that catalyzes the conversion of l-kynurenine (l-Kyn) to 3-hydroxykynurenine (3OHKyn) in the pathway for tryptophan catabolism. KMO inhibition has been widely suggested as an early treatment for stroke and other neurological disorders that involve ischemia. We have investigated the reductive and the oxidative half-reactions of a stable form of KMO from Pseudomonas fluorescens (KMO). The binding of l-Kyn by the enzyme is relatively slow and involves at least two reversible steps. The rate constant for reduction of the flavin cofactor by NADPH increases by a factor of approximately 2.5 x 10(3) when l-Kyn is bound. The rate of reduction of the KMO.l-Kyn complex is 160 s(-1), and the K(d) for the NADPH complex is 200 microM with charge-transfer absorption bands for the KMO(RED).l-Kyn.NADP(+) complex accumulating after reduction. The reduction potential of KMO is -188 mV and is unresponsive to the addition of l-Kyn or other inhibitory ligands. KMO inhibitors whose structures are reminiscent of l-Kyn such as m-nitrobenzoylalanine and benzoylalanine also stimulate reduction of flavin by NADPH and, in the presence of dioxygen, result in the stoichiometric liberation of hydrogen peroxide, diminishing the perceived therapeutic potential of inhibitors of this type. In the presence of the native substrate, the oxidative half-reaction exhibits triphasic absorbance data. A spectrum consistent with that of a peroxyflavin species accumulates and then decays to yield the oxidized enzyme. This species then undergoes minor spectral changes that, based on flavin difference spectra defined in the presence of 3OHKyn, can be correlated with product release. The oxidative half-reaction observed in the presence of saturating benzoylalanine or m-nitrobenzoylalanine also shows the accumulation of a peroxyflavin species that then decays to yield hydrogen peroxide without hydroxylation.

  12. Correlation of circadian changes in tyrosine aminotransferase and tryptophan-2-3-dioxygenase in rat liver to irradiation at different times of the day

    International Nuclear Information System (INIS)

    Toropila, M.; Ahlers, I.; Datelinka, I.; Ahlersova, E.

    1987-01-01

    Male SPF Wistar rats adapted to a 12:12 h light:dark regimen were irradiated at 3-hour intervals in the course of 24 h with a dose of 14.35 Gy of X-rays; 24 h after irradiation or sham irradiation and starvation for the same length of time, and also in fed intact rats, tyrosine aminotransferase and tryptophan-2-3-dioxygenase activities in the liver, and the serum corticosterone level were determined. Although lethal irradiation modified the given enzyme activities, it did not abolish their circadian rhythm, evidently in association with the low sensitivity of the liver to ionizing radiation. In the irradiated animals (compared with sham-irradiated animals), the serum corticosterone concentration fell during the light part of the day and at the beginning of the dark part. (author). 3 figs., 13 refs

  13. Cumulative effect of X-ray radiation and inflammatory reaction on the circadian rhythm of tyrosine aminotransferase in the liver of mice

    International Nuclear Information System (INIS)

    Jungowska-Klin, B.

    1980-01-01

    The activity of tyrosine aminotransferase (TAT) in the liver of mice subjected simultaneously to ionizing radiation and to local inflammatory process showed in the first 24 hours of the experiment statistically significant changes resulting from summation of the harmful effects of both factors. In the second 24-hour period an evident tendency was observed for return of a normal circadian rhythm of the enzyme. This points to presence of an endogenous mechanism of suppression of the manifestations of significant desynchronization of the circadian rhythm. The paper contains also a trial of mathematical analysis of changes in TAT activity in the circadian rhythm, a description and analysis or the suppression process, qualitative and quantitative determination of the phenomenon of cumulation of the effects of powerful stress factors acting on the animal organism. The obtained results were compared with the results of investigations of TAT activity changes obtained in the case of separate application of the stress factors selected for this experiment. (author)

  14. Analysis of cardiomyocyte movement in the developing murine heart

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Hisayuki [Department of Cardiology, Keio University School of Medicine, Tokyo (Japan); Yuasa, Shinsuke, E-mail: yuasa@a8.keio.jp [Department of Cardiology, Keio University School of Medicine, Tokyo (Japan); Tabata, Hidenori [Department of Anatomy, Keio University School of Medicine, Tokyo (Japan); Tohyama, Shugo; Seki, Tomohisa; Egashira, Toru; Hayashiji, Nozomi; Hattori, Fumiyuki; Kusumoto, Dai; Kunitomi, Akira; Takei, Makoto; Kashimura, Shin; Yozu, Gakuto; Shimojima, Masaya; Motoda, Chikaaki; Muraoka, Naoto [Department of Cardiology, Keio University School of Medicine, Tokyo (Japan); Nakajima, Kazunori [Department of Anatomy, Keio University School of Medicine, Tokyo (Japan); Sakaue-Sawano, Asako; Miyawaki, Atsushi [Life Function and Dynamics, ERATO, JST, 2-1 Hirosawa, Wako-city, Saitama 351-0198 (Japan); Laboratory for Cell Function and Dynamics, Advanced Technology Development Group, Brain Science Institute, RIKEN, 2-1 Hirosawa, Wako-city, Saitama 351-0198 (Japan); Fukuda, Keiichi [Department of Cardiology, Keio University School of Medicine, Tokyo (Japan)

    2015-09-04

    The precise assemblage of several types of cardiac precursors controls heart organogenesis. The cardiac precursors show dynamic movement during early development and then form the complicated heart structure. However, cardiomyocyte movements inside the newly organized mammalian heart remain unclear. We previously established the method of ex vivo time-lapse imaging of the murine heart to study cardiomyocyte behavior by using the Fucci (fluorescent ubiquitination-based cell cycle indicator) system, which can effectively label individual G1, S/G2/M, and G1/S-transition phase nuclei in living cardiomyocytes as red, green, and yellow, respectively. Global analysis of gene expression in Fucci green positive ventricular cardiomyocytes confirmed that cell cycle regulatory genes expressed in G1/S, S, G2/M, and M phase transitions were upregulated. Interestingly, pathway analysis revealed that many genes related to the cell cycle were significantly upregulated in the Fucci green positive ventricular cardiomyocytes, while only a small number of genes related to cell motility were upregulated. Time-lapse imaging showed that murine proliferating cardiomyocytes did not exhibit dynamic movement inside the heart, but stayed on site after entering the cell cycle. - Highlights: • We directly visualized cardiomyocyte movement inside the developing murine heart. • Cell cycle related genes were upregulated in the proliferating cardiomyocytes. • Time-lapse imaging revealed that proliferating murine cardiomyocytes stayed in place. • Murine ventricular cardiomyocytes proliferate on site during development.

  15. Murine Typhus: An Important Consideration for the Nonspecific Febrile Illness

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    Gurjot Basra

    2012-01-01

    Full Text Available Murine typhus is a widely distributed flea-borne infection caused by Rickettsia typhi. Symptoms of murine typhus are nonspecific and mimic a variety of other infectious diseases. We herein report a case of murine typhus in an area where the broad use of DDT in the mid-20th century has now made it a rare disease. The patient described presented with headache, fever, and a faint macular rash. Initial laboratory studies revealed a slight transaminase elevation. Further questioning revealed exposure to opossums, prompting the consideration of murine typhus as a diagnosis. Although typhus group antibodies were not present during the patient’s acute illness, empiric therapy with doxycycline was initiated, and the patient defervesced. One month after convalescence, the patient returned to clinic with serum that contained typhus group antibodies with an IgG titer of 1 : 1024. Murine typhus is an important consideration during the workup of a patient with a nonspecific febrile illness. Exposure to reservoir hosts and the flea vector place humans at risk for this disease. Clinician recognition of this entity is required for diagnosis and effective therapy.

  16. L,L-diaminopimelate aminotransferase, a trans-kingdom enzyme shared by Chlamydia and plants for synthesis of diaminopimelate/lysine.

    Science.gov (United States)

    McCoy, Andrea J; Adams, Nancy E; Hudson, André O; Gilvarg, Charles; Leustek, Thomas; Maurelli, Anthony T

    2006-11-21

    The synthesis of meso-diaminopimelic acid (m-DAP) in bacteria is essential for both peptidoglycan and lysine biosynthesis. From genome sequencing data, it was unclear how bacteria of the Chlamydiales order would synthesize m-DAP in the absence of dapD, dapC, and dapE, which are missing from the genome. Here, we assessed the biochemical capacity of Chlamydia trachomatis serovar L2 to synthesize m-DAP. Expression of the chlamydial asd, dapB, and dapF genes in the respective Escherichia coli m-DAP auxotrophic mutants restored the mutants to DAP prototrophy. Screening of a C. trachomatis genomic library in an E. coli DeltadapD DAP auxotroph identified ct390 as encoding an enzyme that restored growth to the Escherichia coli mutant. ct390 also was able to complement an E. coli DeltadapD DeltadapE, but not a DeltadapD DeltadapF mutant, providing genetic evidence that it encodes an aminotransferase that may directly convert tetrahydrodipicolinate to L,L-diaminopimelic acid. This hypothesis was supported by in vitro kinetic analysis of the CT390 protein and the fact that similar properties were demonstrated for the Protochlamydia amoebophila homologue, PC0685. In vivo, the C. trachomatis m-DAP synthesis genes are expressed as early as 8 h after infection. An aminotransferase activity analogous to CT390 recently has been characterized in plants and cyanobacteria. This previously undescribed pathway for m-DAP synthesis supports an evolutionary relationship among the chlamydiae, cyanobacteria, and plants and strengthens the argument that chlamydiae synthesize a cell wall despite the inability of efforts to date to detect peptidoglycan in these organisms.

  17. The mechanical fingerprint of murine excisional wounds.

    Science.gov (United States)

    Pensalfini, Marco; Haertel, Eric; Hopf, Raoul; Wietecha, Mateusz; Werner, Sabine; Mazza, Edoardo

    2018-01-01

    A multiscale mechanics approach to the characterization of murine excisional wounds subjected to uniaxial tensile loading is presented. Local strain analysis at a physiological level of tension uncovers the presence of two distinct regions within the wound: i) a very compliant peripheral cushion and ii) a core area undergoing modest deformation. Microstructural visualizations of stretched wound specimens show negligible engagement of the collagen located in the center of a 7-day old wound; fibers remain coiled despite the applied tension, confirming the existence of a mechanically isolated wound core. The compliant cushion located at the wound periphery appears to protect the newly-formed tissue from excessive deformation during the phase of new tissue formation. The early remodeling phase (day 14) is characterized by a restored mechanical connection between far field and wound center. The latter remains less deformable, a characteristic possibly required for cell activities during tissue remodeling. The distribution of fibrillary collagens at these two time points corresponds well to the identified heterogeneity of mechanical properties of the wound region. This novel approach provides new insight into the mechanical properties of wounded skin and will be applicable to the analysis of compound-treated wounds or wounds in genetically modified tissue. Biophysical characterization of healing wounds is crucial to assess the recovery of the skin barrier function and the associated mechanobiological processes. For the first time, we performed highly resolved local deformation analysis to identify mechanical characteristics of the wound and its periphery. Our results reveal the presence of a compliant cushion surrounding a stiffer wound core; we refer to this heterogeneous mechanical behavior as "mechanical fingerprint" of the wound. The mechanical response is shown to progress towards that of the intact skin as healing takes place. Histology and multiphoton microscopy

  18. Preclinical Murine Models for Lung Cancer: Clinical Trial Applications

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    Amelia Kellar

    2015-01-01

    Full Text Available Murine models for the study of lung cancer have historically been the backbone of preliminary preclinical data to support early human clinical trials. However, the availability of multiple experimental systems leads to debate concerning which model, if any, is best suited for a particular therapeutic strategy. It is imperative that these models accurately predict clinical benefit of therapy. This review provides an overview of the current murine models used to study lung cancer and the advantages and limitations of each model, as well as a retrospective evaluation of the uses of each model with respect to accuracy in predicting clinical benefit of therapy. A better understanding of murine models and their uses, as well as their limitations may aid future research concerning the development and implementation of new targeted therapies and chemotherapeutic agents for lung cancer.

  19. Murine Models of Gastric Corpus PreneoplasiaSummary

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    Christine P. Petersen

    2017-01-01

    Full Text Available Intestinal-type gastric adenocarcinoma evolves in a field of pre-existing metaplasia. Over the past 20 years, a number of murine models have been developed to address aspects of the physiology and pathophysiology of metaplasia induction. Although none of these models has achieved true recapitulation of the induction of adenocarcinoma, they have led to important insights into the factors that influence the induction and progression of metaplasia. Here, we review the pathologic definitions relevant to alterations in gastric corpus lineages and classification of metaplasia by specific lineage markers. In addition, we review present murine models of the induction and progression of spasmolytic polypeptide (TFF2–expressing metaplasia, the predominant metaplastic lineage observed in murine models. These models provide a basis for the development of a broader understanding of the physiological and pathophysiological roles of metaplasia in the stomach. Keywords: SPEM, Intestinal Metaplasia, Gastric Cancer, TFF2, Chief Cell, Hyperplasia

  20. A rapid murine coma and behavior scale for quantitative assessment of murine cerebral malaria.

    Directory of Open Access Journals (Sweden)

    Ryan W Carroll

    Full Text Available BACKGROUND: Cerebral malaria (CM is a neurological syndrome that includes coma and seizures following malaria parasite infection. The pathophysiology is not fully understood and cannot be accounted for by infection alone: patients still succumb to CM, even if the underlying parasite infection has resolved. To that effect, there is no known adjuvant therapy for CM. Current murine CM (MCM models do not allow for rapid clinical identification of affected animals following infection. An animal model that more closely mimics the clinical features of human CM would be helpful in elucidating potential mechanisms of disease pathogenesis and evaluating new adjuvant therapies. METHODOLOGY/PRINCIPAL FINDINGS: A quantitative, rapid murine coma and behavior scale (RMCBS comprised of 10 parameters was developed to assess MCM manifested in C57BL/6 mice infected with Plasmodium berghei ANKA (PbA. Using this method a single mouse can be completely assessed within 3 minutes. The RMCBS enables the operator to follow the evolution of the clinical syndrome, validated here by correlations with intracerebral hemorrhages. It provides a tool by which subjects can be identified as symptomatic prior to the initiation of trial treatment. CONCLUSIONS/SIGNIFICANCE: Since the RMCBS enables an operator to rapidly follow the course of disease, label a subject as affected or not, and correlate the level of illness with neuropathologic injury, it can ultimately be used to guide the initiation of treatment after the onset of cerebral disease (thus emulating the situation in the field. The RMCBS is a tool by which an adjuvant therapy can be objectively assessed.

  1. Nanoelectroablation therapy for murine basal cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Nuccitelli, Richard, E-mail: rich@bioelectromed.com [BioElectroMed Corp., 849 Mitten Rd., Suite 104, Burlingame, CA 94010 (United States); Tran, Kevin; Athos, Brian; Kreis, Mark; Nuccitelli, Pamela [BioElectroMed Corp., 849 Mitten Rd., Suite 104, Burlingame, CA 94010 (United States); Chang, Kris S.; Epstein, Ervin H. [The Children' s Hospital Oakland Research Institute, Oakland, CA 94609 (United States); Tang, Jean Y. [The Children' s Hospital Oakland Research Institute, Oakland, CA 94609 (United States); Stanford University, Stanford, CA 94305 (United States)

    2012-08-03

    Highlights: Black-Right-Pointing-Pointer Nanoelectroablation is a new, non-thermal therapy that triggers apoptosis in tumors. Black-Right-Pointing-Pointer Low energy, ultrashort, high voltage pulses ablate the tumor with little or no scar. Black-Right-Pointing-Pointer Nanoelectroablation eliminates 99.8% of the BCC but may leave a few remnants behind. Black-Right-Pointing-Pointer Pilot clinical trials on human BCCs are ongoing and leave no remnants in most cases. -- Abstract: When skin tumors are exposed to non-thermal, low energy, nanosecond pulsed electric fields (nsPEF), apoptosis is initiated both in vitro and in vivo. This nanoelectroablation therapy has already been proven effective in treating subdermal murine allograft tumors. We wanted to determine if this therapy would be equally effective in the treatment of autochthonous BCC tumors in Ptch1{sup +/-}K14-Cre-ER p53 fl/fl mice. These tumors are similar to human BCCs in histology and in response to drug therapy . We have treated 27 BCCs across 8 mice with either 300 pulses of 300 ns duration or 2700 pulses of 100 ns duration, all at 30 kV/cm and 5-7 pulses per second. Every nsPEF-treated BCC began to shrink within a day after treatment and their initial mean volume of 36 {+-} 5 (SEM) mm{sup 3} shrunk by 76 {+-} 3% over the ensuing two weeks. After four weeks, they were 99.8% ablated if the size of the treatment electrode matched the tumor size. If the tumor was larger than the 4 mm wide electrode, multiple treatments were needed for complete ablation. Treated tumors were harvested for histological analysis at various times after treatment and exhibited apoptosis markers. Specifically, pyknosis of nuclei was evident as soon as 2 days after nsPEF treatment, and DNA fragmentation as detected via TUNEL staining was also evident post treatment. Nanoelectroablation is effective in triggering apoptosis and remission of radiation-induced BCCs with a single 6 min-long treatment of 2700 pulses.

  2. Concentrações de creatino quinase, aspartato aminotransferase e desidrogenase lática em potros do nascimento até os seis meses de idade Concentration of creatine kinase, aspartate aminotransferase and lactate dehydrogenase in foals from birth up to sixth month

    Directory of Open Access Journals (Sweden)

    Elisiane Lourdes Da Cás

    2001-12-01

    Full Text Available Dez potros da raça Puro Sangue de Corrida (PSC, de ambos os sexos, foram avaliados quanto à concentração das enzimas séricas creatino quinase (CK, aspartato aminotransferase (AST e deshidrogenase lática (DHL. Foram colhidas amostras sangüíneas diariamente do 1º ao 7ºdia de vida e depois aos 15, 30, 60, 90, 120, 150 e 180 dias de idade. A concentração da CK mostrou um decréscimo significativo (pTen Thoroughbred foals, male and female, had the seric concentration of creatine kinase (CK, aspartate aminotransferase (AST and lactate dehydrogenase (LDH determined. Blood samples were collected every day from days 1 to 7 and on days 15, 30, 60, 90, 120, 150 and 180 of age. CK activity decreased significantly (p< 0.0003 in the first week and showed significant variation between day 15 and 6 months of age. AST showed a significant (p< 0.0001 increase in its values until 102 days of age, decreasing subsequently until 6 months of age. LDH values decreased significantly (p< 0.0002 between days 15 and 120, increasing subsequently until 6 months of age. At 6 months of age CK, AST and LDH activities were close to those of adult horses.

  3. Directed evolution and targeted mutagenesis to murinize Listeria monocytogenes Internalin A for enhanced infectivity in the murine oral infection model

    LENUS (Irish Health Repository)

    Monk, Ian R

    2010-12-13

    Abstract Background Internalin A (InlA) is a critical virulence factor which mediates the initiation of Listeria monocytogenes infection by the oral route in permissive hosts. The interaction of InlA with the host cell ligand E-cadherin efficiently stimulates L. monocytogenes entry into human enterocytes, but has only a limited interaction with murine cells. Results We have created a surface display library of randomly mutated InlA in a non-invasive heterologous host Lactococcus lactis in order to create and screen novel variants of this invasion factor. After sequential passage through a murine cell line (CT-26), multiple clones with enhanced invasion characteristics were identified. Competitive index experiments were conducted in mice using selected mutations introduced into L. monocytogenes EGD-e background. A novel single amino acid change was identified which enhanced virulence by the oral route in the murine model and will form the basis of further engineering approaches. As a control a previously described EGD-InlAm murinized strain was also re-created as part of this study with minor modifications and designated EGD-e InlA m*. The strain was created using a procedure that minimizes the likelihood of secondary mutations and incorporates Listeria-optimized codons encoding the altered amino acids. L. monocytogenes EGD-e InlA m* yielded consistently higher level murine infections by the oral route when compared to EGD-e, but did not display the two-fold increased invasion into a human cell line that was previously described for the EGD-InlAm strain. Conclusions We have used both site-directed mutagenesis and directed evolution to create variants of InlA which may inform future structure-function analyses of this protein. During the course of the study we engineered a murinized strain of L. monocytogenes EGD-e which shows reproducibly higher infectivity in the intragastric murine infection model than the wild type, but does not display enhanced entry into human

  4. Directed evolution and targeted mutagenesis to murinize listeria monocytogenes internalin A for enhanced infectivity in the murine oral infection model

    Directory of Open Access Journals (Sweden)

    Hill Colin

    2010-12-01

    Full Text Available Abstract Background Internalin A (InlA is a critical virulence factor which mediates the initiation of Listeria monocytogenes infection by the oral route in permissive hosts. The interaction of InlA with the host cell ligand E-cadherin efficiently stimulates L. monocytogenes entry into human enterocytes, but has only a limited interaction with murine cells. Results We have created a surface display library of randomly mutated InlA in a non-invasive heterologous host Lactococcus lactis in order to create and screen novel variants of this invasion factor. After sequential passage through a murine cell line (CT-26, multiple clones with enhanced invasion characteristics were identified. Competitive index experiments were conducted in mice using selected mutations introduced into L. monocytogenes EGD-e background. A novel single amino acid change was identified which enhanced virulence by the oral route in the murine model and will form the basis of further engineering approaches. As a control a previously described EGD-InlAm murinized strain was also re-created as part of this study with minor modifications and designated EGD-e InlAm*. The strain was created using a procedure that minimizes the likelihood of secondary mutations and incorporates Listeria-optimized codons encoding the altered amino acids. L. monocytogenes EGD-e InlAm* yielded consistently higher level murine infections by the oral route when compared to EGD-e, but did not display the two-fold increased invasion into a human cell line that was previously described for the EGD-InlAm strain. Conclusions We have used both site-directed mutagenesis and directed evolution to create variants of InlA which may inform future structure-function analyses of this protein. During the course of the study we engineered a murinized strain of L. monocytogenes EGD-e which shows reproducibly higher infectivity in the intragastric murine infection model than the wild type, but does not display enhanced

  5. Transgene stability for three replication competent murine leukemia virus vectors

    DEFF Research Database (Denmark)

    Duch, M.; Carrasco, M.L.; Jespersen, T.

    2004-01-01

    cassette consisting of an internal ribosome entry site followed by the enhanced green fluorescent protein coding sequence inserted in different configurations into murine leukemia virus genomes. In two of the constructs, the insert was located in the upstream part of the U3 region while in the third...

  6. Murine alpha1-adrenoceptor subtypes. I. Radioligand binding studies

    NARCIS (Netherlands)

    Yang, M.; Reese, J.; Cotecchia, S.; Michel, M. C.

    1998-01-01

    Alpha1-adrenoceptors were identified in murine tissues by [3H]prazosin saturation binding studies, with a rank order of cerebral cortex > cerebellum > liver > lung > kidney > heart > spleen, with the spleen not exhibiting detectable expression. Competition binding studies were performed with

  7. Reversal of Liver Fibrosis in Chronic Murine Schistosomiasis ...

    African Journals Online (AJOL)

    NO Al-Harbi, SA Bahashwan, MS Aboonq, MA Ramadan, AA Bahashwan. Abstract. Purpose: To evaluate the safety, pharmacological effect and mechanism of action of an antifibrotic compound, safironil (SAF)/praziquantel (PZQ) combination on reversal of liver fibrogenesis in chronic murine Schistosomiasis mansoni.

  8. Protective antitumor activity induced by a fusion vaccine with murine ...

    African Journals Online (AJOL)

    Targeting angiogenesis is an effective strategy for anticancer therapy. The vascular endothelialcadherin (VE-cad) regulated angiogenesis is a potential target for anti-angiogenesis. Here, we develop a fusion vaccine plasmid DNA pSec-MBD2-VE-cad from VE-cad and murine beta defensin2 (MBD2) to induce immunity for ...

  9. Topical Apigenin Alleviates Cutaneous Inflammation in Murine Models

    Directory of Open Access Journals (Sweden)

    Mao-Qiang Man

    2012-01-01

    Full Text Available Herbal medicines have been used in preventing and treating skin disorders for centuries. It has been demonstrated that systemic administration of chrysanthemum extract exhibits anti-inflammatory properties. However, whether topical applications of apigenin, a constituent of chrysanthemum extract, influence cutaneous inflammation is still unclear. In the present study, we first tested whether topical applications of apigenin alleviate cutaneous inflammation in murine models of acute dermatitis. The murine models of acute allergic contact dermatitis and acute irritant contact dermatitis were established by topical application of oxazolone and phorbol 12-myristate 13-acetate (TPA, respectively. Inflammation was assessed in both dermatitis models by measuring ear thickness. Additionally, the effect of apigenin on stratum corneum function in a murine subacute allergic contact dermatitis model was assessed with an MPA5 physiology monitor. Our results demonstrate that topical applications of apigenin exhibit therapeutic effects in both acute irritant contact dermatitis and allergic contact dermatitis models. Moreover, in comparison with the vehicle treatment, topical apigenin treatment significantly reduced transepidermal water loss, lowered skin surface pH, and increased stratum corneum hydration in a subacute murine allergic contact dermatitis model. Together, these results suggest that topical application of apigenin could provide an alternative regimen for the treatment of dermatitis.

  10. Turnover of T cells in murine gammaherpesvirus 68-infected mice

    DEFF Research Database (Denmark)

    Hamilton-Easton, A M; Christensen, Jan Pravsgaard; Doherty, P C

    1999-01-01

    Respiratory challenge of C57BL/6 mice with murine gammaherpesvirus 68 induces proliferation of T lymphocytes early after infection, as evidenced by incorporation of the DNA precursor bromodeoxyuridine. Using pulse-chase analysis, splenic and peripheral blood activated T lymphocytes were found...

  11. Expression of biologically active murine interleukin-18 in Lactococcus lactis.

    Science.gov (United States)

    Feizollahzadeh, Sadegh; Khanahmad, Hossein; Rahimmanesh, Ilnaz; Ganjalikhani-Hakemi, Mazdak; Andalib, Alireza; Sanei, Mohammad Hossein; Rezaei, Abbas

    2016-11-01

    The food-grade bacterium Lactococcus lactis is increasingly used for heterologous protein expression in therapeutic and industrial applications. The ability of L. lactis to secrete biologically active cytokines may be used for the generation of therapeutic cytokines. Interleukin (IL)-18 enhances the immune response, especially on mucosal surfaces, emphasizing its therapeutic potential. However, it is produced as an inactive precursor and has to be enzymatically cleaved for maturation. We genetically manipulated L. lactis to secrete murine IL-18. The mature murine IL-18 gene was inserted downstream of a nisin promoter in pNZ8149 plasmid and the construct was used to transform L. lactis NZ3900. The transformants were selected on Elliker agar and confirmed by restriction enzyme digestion and sequencing. The expression and secretion of IL-18 protein was verified by SDS-PAGE, western blotting and ELISA. The biological activity of recombinant IL-18 was determined by its ability to induce interferon (IFN)-γ production in L. lactis co-cultured with murine splenic T cells. The amounts of IL-18 in bacterial lysates and supernatants were 3-4 μg mL -1 and 0.6-0.7 ng mL -1 , respectively. The successfully generated L. lactis strain that expressed biologically active murine IL-18 can be used to evaluate the possible therapeutic effects of IL-18 on mucosal surfaces. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  12. Simple serum markers for significant liver inflammation in chronic hepatitis B patients with an alanine aminotransferase level lower than 2 times upper limit of normal

    Directory of Open Access Journals (Sweden)

    LI Qiang

    2016-06-01

    Full Text Available ObjectiveTo investigate the simple serum markers for significant liver inflammation in chronic hepatitis B (CHB patients with an alanine aminotransferase (ALT level of <2 times upper limit of normal (ULN. MethodsThe clinical data of 278 CHB patients with ALT <2×ULN (ULN=40 U/L were analyzed retrospectively. Significant liver inflammation was defined as a liver inflammatory activity grade (G ≥2. The t-test was used for comparison of normally distributed continuous data between groups, and the Kruskal-Wallis rank sum test was used for non-normally distributed continuous data; the chi-square test was used for comparison of categorical data between groups. Multivariate logistic regression analysis was used to identify independent predictors for significant liver inflammation in CHB patients with ALT <2×ULN. The receiver operating characteristic (ROC curve was used to evaluate the diagnostic value of serum markers in significant liver inflammation. ResultsOf the 278 CHB patients enrolled, 175 (62.9% had no significant liver inflammation (G0-1 group and 103 (37.1% had significant liver inflammation (G2-4 group. There were significant differences in ALT, aspartate aminotransferase, alkaline phosphatase, gamma-glutamyl transpeptidase (GGT, albumin, globulin, prothrombin time (PT, platelet, absolute neutrophil count, hyaluronic acid (HA, glycocholic acid, precollagen Ⅲ, and collagen type Ⅳ(ⅣC between the two groups (all P<0.05. The multivariate regression analysis showed that GGT, PT, ⅣC, and HA were independent predictors for significant liver inflammation in CHB patients with ALT<2×ULN (OR=1.015, 1.600, 1.151, and 1.014, P=0.008, 0.021, 0.003, and 0.018. The areas under the ROC curve for GGT, PT, IVC, and HA to diagnose significant liver inflammation were 0.804, 0.722, 0.707, and 0.632, respectively. The cut-off value of 48.5 U/L for GGT to predict significant liver inflammation had a specificity of 90.3% and a negative

  13. Inhibition of the aryl hydrocarbon receptor prevents Western diet-induced obesity. Model for AHR activation by kynurenine via oxidized-LDL, TLR2/4, TGFβ, and IDO1

    Energy Technology Data Exchange (ETDEWEB)

    Moyer, Benjamin J. [Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Dartmouth Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH 03756 (United States); Rojas, Itzel Y. [Department of Medicine, Geisel School of Medicine at Dartmouth, Dartmouth Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH 03756 (United States); Department of Pharmacology & Toxicology, Geisel School of Medicine at Dartmouth, Dartmouth Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH 03756 (United States); Kerley-Hamilton, Joanna S. [Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Dartmouth Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH 03756 (United States); Hazlett, Haley F. [Department of Pharmacology & Toxicology, Geisel School of Medicine at Dartmouth, Dartmouth Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH 03756 (United States); Department of Immunology & Microbiology, Geisel School of Medicine at Dartmouth, Dartmouth Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH 03756 (United States); Nemani, Krishnamurthy V. [Department of Radiology, Geisel School of Medicine at Dartmouth, Dartmouth Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH 03756 (United States); Trask, Heidi W.; West, Rachel J. [Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Dartmouth Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH 03756 (United States); Lupien, Leslie E. [Department of Medicine, Geisel School of Medicine at Dartmouth, Dartmouth Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH 03756 (United States); Collins, Alan J. [Department of Immunology & Microbiology, Geisel School of Medicine at Dartmouth, Dartmouth Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH 03756 (United States); and others

    2016-06-01

    Obesity is an increasingly urgent global problem, yet, little is known about its causes and less is known how obesity can be effectively treated. We showed previously that the aryl hydrocarbon receptor (AHR) plays a role in the regulation of body mass in mice fed Western diet. The AHR is a ligand-activated nuclear receptor that regulates genes involved in a number of biological pathways, including xenobiotic metabolism and T cell polarization. This study was an investigation into whether inhibition of the AHR prevents Western diet-based obesity. Male C57Bl/6J mice were fed control and Western diets with and without the AHR antagonist α-naphthoflavone or CH-223191, and a mouse hepatocyte cell line was used to delineate relevant cellular pathways. Studies are presented showing that the AHR antagonists α-naphthoflavone and CH-223191 significantly reduce obesity and adiposity and ameliorates liver steatosis in male C57Bl/6J mice fed a Western diet. Mice deficient in the tryptophan metabolizing enzyme indoleamine 2,3-dioxygenase 1 (IDO1) were also resistant to obesity. Using an AHR-directed, luciferase-expressing mouse hepatocyte cell line, we show that the transforming growth factor β1 (TGFβ1) signaling pathway via PI3K and NF-κB and the toll-like receptor 2/4 (TLR2/4) signaling pathway stimulated by oxidized low-density lipoproteins via NF-κB, each induce luciferase expression; however, TLR2/4 signaling was significantly reduced by inhibition of IDO1. At physiological levels, kynurenine but not kynurenic acid (both tryptophan metabolites and known AHR agonists) activated AHR-directed luciferase expression. We propose a hepatocyte-based model, in which kynurenine production is increased by enhanced IDO1 activity stimulated by TGFβ1 and TLR2/4 signaling, via PI3K and NF-κB, to perpetuate a cycle of AHR activation to cause obesity; and inhibition of the AHR, in turn, blocks the cycle's output to prevent obesity. The AHR with its broad ligand binding

  14. Inhibition of the aryl hydrocarbon receptor prevents Western diet-induced obesity. Model for AHR activation by kynurenine via oxidized-LDL, TLR2/4, TGFβ, and IDO1

    International Nuclear Information System (INIS)

    Moyer, Benjamin J.; Rojas, Itzel Y.; Kerley-Hamilton, Joanna S.; Hazlett, Haley F.; Nemani, Krishnamurthy V.; Trask, Heidi W.; West, Rachel J.; Lupien, Leslie E.; Collins, Alan J.

    2016-01-01

    Obesity is an increasingly urgent global problem, yet, little is known about its causes and less is known how obesity can be effectively treated. We showed previously that the aryl hydrocarbon receptor (AHR) plays a role in the regulation of body mass in mice fed Western diet. The AHR is a ligand-activated nuclear receptor that regulates genes involved in a number of biological pathways, including xenobiotic metabolism and T cell polarization. This study was an investigation into whether inhibition of the AHR prevents Western diet-based obesity. Male C57Bl/6J mice were fed control and Western diets with and without the AHR antagonist α-naphthoflavone or CH-223191, and a mouse hepatocyte cell line was used to delineate relevant cellular pathways. Studies are presented showing that the AHR antagonists α-naphthoflavone and CH-223191 significantly reduce obesity and adiposity and ameliorates liver steatosis in male C57Bl/6J mice fed a Western diet. Mice deficient in the tryptophan metabolizing enzyme indoleamine 2,3-dioxygenase 1 (IDO1) were also resistant to obesity. Using an AHR-directed, luciferase-expressing mouse hepatocyte cell line, we show that the transforming growth factor β1 (TGFβ1) signaling pathway via PI3K and NF-κB and the toll-like receptor 2/4 (TLR2/4) signaling pathway stimulated by oxidized low-density lipoproteins via NF-κB, each induce luciferase expression; however, TLR2/4 signaling was significantly reduced by inhibition of IDO1. At physiological levels, kynurenine but not kynurenic acid (both tryptophan metabolites and known AHR agonists) activated AHR-directed luciferase expression. We propose a hepatocyte-based model, in which kynurenine production is increased by enhanced IDO1 activity stimulated by TGFβ1 and TLR2/4 signaling, via PI3K and NF-κB, to perpetuate a cycle of AHR activation to cause obesity; and inhibition of the AHR, in turn, blocks the cycle's output to prevent obesity. The AHR with its broad ligand binding

  15. Current Translational Research and Murine Models For Duchenne Muscular Dystrophy

    Science.gov (United States)

    Rodrigues, Merryl; Echigoya, Yusuke; Fukada, So-ichiro; Yokota, Toshifumi

    2016-01-01

    Duchenne muscular dystrophy (DMD) is an X-linked genetic disorder characterized by progressive muscle degeneration. Mutations in the DMD gene result in the absence of dystrophin, a protein required for muscle strength and stability. Currently, there is no cure for DMD. Since murine models are relatively easy to genetically manipulate, cost effective, and easily reproducible due to their short generation time, they have helped to elucidate the pathobiology of dystrophin deficiency and to assess therapies for treating DMD. Recently, several murine models have been developed by our group and others to be more representative of the human DMD mutation types and phenotypes. For instance, mdx mice on a DBA/2 genetic background, developed by Fukada et al., have lower regenerative capacity and exhibit very severe phenotype. Cmah-deficient mdx mice display an accelerated disease onset and severe cardiac phenotype due to differences in glycosylation between humans and mice. Other novel murine models include mdx52, which harbors a deletion mutation in exon 52, a hot spot region in humans, and dystrophin/utrophin double-deficient (dko), which displays a severe dystrophic phenotype due the absence of utrophin, a dystrophin homolog. This paper reviews the pathological manifestations and recent therapeutic developments in murine models of DMD such as standard mdx (C57BL/10), mdx on C57BL/6 background (C57BL/6-mdx), mdx52, dystrophin/utrophin double-deficient (dko), mdxβgeo, Dmd-null, humanized DMD (hDMD), mdx on DBA/2 background (DBA/2-mdx), Cmah-mdx, and mdx/mTRKO murine models. PMID:27854202

  16. Directed evolution and targeted mutagenesis to murinize Listeria monocytogenes internalin A for enhanced infectivity in the murine oral infection model.

    LENUS (Irish Health Repository)

    Monk, Ian R

    2010-01-01

    Internalin A (InlA) is a critical virulence factor which mediates the initiation of Listeria monocytogenes infection by the oral route in permissive hosts. The interaction of InlA with the host cell ligand E-cadherin efficiently stimulates L. monocytogenes entry into human enterocytes, but has only a limited interaction with murine cells.

  17. Single Amino Acid Insertion in Loop 4 Confers Amphotropic Murine Leukemia Virus Receptor Function upon Murine Pit1

    DEFF Research Database (Denmark)

    Lundorf, Mikkel D.; Pedersen, Finn Skou; O'Hara, Bryan

    1998-01-01

    Pit1 is the human receptor for gibbon ape leukemia virus (GALV) and feline leukemia virus subgroup B (FeLV-B), while the related human protein Pit2 is a receptor for amphotropic murine leukemia virus (A-MuLV). The A-MuLV-related isolate 10A1 can utilize both Pit1 and Pit2 as receptors. A stretch...

  18. Biochemical and phylogenetic characterization of a novel diaminopimelate biosynthesis pathway in prokaryotes identifies a diverged form of LL-diaminopimelate aminotransferase.

    Science.gov (United States)

    Hudson, André O; Gilvarg, Charles; Leustek, Thomas

    2008-05-01

    A variant of the diaminopimelate (DAP)-lysine biosynthesis pathway uses an LL-DAP aminotransferase (DapL, EC 2.6.1.83) to catalyze the direct conversion of L-2,3,4,5-tetrahydrodipicolinate to LL-DAP. Comparative genomic analysis and experimental verification of DapL candidates revealed the existence of two diverged forms of DapL (DapL1 and DapL2). DapL orthologs were identified in eubacteria and archaea. In some species the corresponding dapL gene was found to lie in genomic contiguity with other dap genes, suggestive of a polycistronic structure. The DapL candidate enzymes were found to cluster into two classes sharing approximately 30% amino acid identity. The function of selected enzymes from each class was studied. Both classes were able to functionally complement Escherichia coli dapD and dapE mutants and to catalyze LL-DAP transamination, providing functional evidence for a role in DAP/lysine biosynthesis. In all cases the occurrence of dapL in a species correlated with the absence of genes for dapD and dapE representing the acyl DAP pathway variants, and only in a few cases was dapL coincident with ddh encoding meso-DAP dehydrogenase. The results indicate that the DapL pathway is restricted to specific lineages of eubacteria including the Cyanobacteria, Desulfuromonadales, Firmicutes, Bacteroidetes, Chlamydiae, Spirochaeta, and Chloroflexi and two archaeal groups, the Methanobacteriaceae and Archaeoglobaceae.

  19. PsAAT3, an oomycete-specific aspartate aminotransferase, is required for full pathogenicity of the oomycete pathogen Phytophthora sojae.

    Science.gov (United States)

    Wang, Rongbo; Zhang, Meixiang; Liu, Hong; Xu, Jing; Yu, Jia; He, Feng; Zhang, Xiong; Dong, Suomeng; Dou, Daolong

    2016-04-01

    Pathogen nutrient acquisition and metabolism are critical for successful infection and colonization. However, the nutrient requirements and metabolic pathways related to pathogenesis in oomycete pathogens are unknown. In this study, we bioinformatically identified Phytophthora sojae aspartate aminotransferases (AATs), which are key enzymes that coordinate carbon and nitrogen metabolism. We demonstrated that P. sojae encodes more AATs than the analysed fungi. Some of the AATs contained additional prephenate dehydratase and/or prephenate dehydrogenase domains in their N-termini, which are unique to oomycetes. Silencing of PsAAT3, an infection-inducible expression gene, reduced P. sojae pathogenicity on soybean plants and affected the growth under N-starving condition, suggesting that PsAAT3 is involved in pathogen pathogenicity and nitrogen utilisation during infection. Our results suggest that P. sojae and other oomycete pathogens may have distinct amino acid metabolism pathways and that PsAAT3 is important for its full pathogenicity. Copyright © 2016 The British Mycological Society. Published by Elsevier Ltd. All rights reserved.

  20. Keratin-18 and microRNA-122 complement alanine aminotransferase as novel safety biomarkers for drug-induced liver injury in two human cohorts.

    Science.gov (United States)

    Thulin, Petra; Nordahl, Gunnar; Gry, Marcus; Yimer, Getnet; Aklillu, Eleni; Makonnen, Eyasu; Aderaye, Getachew; Lindquist, Lars; Mattsson, C Mikael; Ekblom, Björn; Antoine, Daniel J; Park, B Kevin; Linder, Stig; Harrill, Alison H; Watkins, Paul B; Glinghammar, Björn; Schuppe-Koistinen, Ina

    2014-03-01

    There is a demand for more sensitive, specific and predictive biomarkers for drug-induced liver injury (DILI) than the gold standard used today, alanine aminotransferase (ALT). The aim of this study was to qualify novel DILI biomarkers (keratin-18 markers M65/M30, microRNA-122, glutamate dehydrogenase and alpha-foetoprotein) in human DILI. Levels of the novel biomarkers were measured by enzyme-linked immunosorbent assay or real-time quantitative reverse-transcription PCR (qRT-PCR) in two human DILI cohorts: a human volunteer study with acetaminophen and a human immunodeficiency virus (HIV)/tuberculosis (TB) study. In the acetaminophen study, serum M65 and microRNA-122 levels were significantly increased at an earlier time point than ALT. Furthermore, the maximal elevation of M65 and microRNA-122 exceeded the increase in ALT. In the HIV/TB study, all the analysed novel biomarkers increased after 1 week of treatment. In contrast to ALT, the novel biomarkers remained stable in a human cohort with exercise-induced muscular injury. M65 and microRNA-122 are potential biomarkers of DILI superior to ALT with respect to sensitivity and specificity. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Partial amino acid sequence of the branched chain amino acid aminotransferase (TmB) of E. coli JA199 pDU11

    International Nuclear Information System (INIS)

    Feild, M.J.; Armstrong, F.B.

    1987-01-01

    E. coli JA199 pDU11 harbors a multicopy plasmid containing the ilv GEDAY gene cluster of S. typhimurium. TmB, gene product of ilv E, was purified, crystallized, and subjected to Edman degradation using a gas phase sequencer. The intact protein yielded an amino terminal 31 residue sequence. Both carboxymethylated apoenzyme and [ 3 H]-NaBH-reduced holoenzyme were then subjected to digestion by trypsin. The digests were fractionated using reversed phase HPLC, and the peptides isolated were sequenced. The borohydride-treated holoenzyme was used to isolate the cofactor-binding peptide. The peptide is 27 residues long and a comparison with known sequences of other aminotransferases revealed limited homology. Peptides accounting for 211 of 288 predicted residues have been sequenced, including 9 residues of the carboxyl terminus. Comparison of peptides with the inferred amino acid sequence of the E. coli K-12 enzyme has helped determine the sequence of the amino terminal 59 residues; only two differences between the sequences are noted in this region

  2. Evaluation of Milk Trace Elements, Lactate Dehydrogenase, Alkaline Phosphatase and Aspartate Aminotransferase Activity of Subclinical Mastitis as and Indicator of Subclinical Mastitis in Riverine Buffalo (Bubalus bubalis).

    Science.gov (United States)

    Guha, Anirban; Gera, Sandeep; Sharma, Anshu

    2012-03-01

    Mastitis is a highly morbid disease that requires detection at the subclinical stage. Tropical countries like India mainly depend on milch buffaloes for milk. The present study was conducted to investigate whether the trace minerals viz. copper (Cu), iron (Fe), zinc (Zn), cobalt (Co) and manganese (Mn) and enzyme activity of lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and aspartate aminotransferase (AST) in riverine buffalo milk can be used as an indicator of subclinical mastitis (SCM) with the aim of developing suitable diagnostic kit for SCM. Trace elements and enzyme activity in milk were estimated with Atomic absorption Spectrophotometer, GBC 932 plus and biochemical methods, respectively. Somatic cell count (SCC) was done microscopically. The cultural examination revealed Gram positive bacteria as the most prevalent etiological agent. A statistically significant (pnegative bacteria. The percent sensitivity, specificity and accuracy, predictive values and likelihood ratios were calculated taking bacterial culture examination and SCC≥2×10(5) cells/ml of milk as the benchmark. Only ALP and Zn, the former being superior, were found to be suitable for diagnosis of SCM irrespective of etiological agents. LDH, Co and Fe can be introduced in the screening programs where Gram positive bacteria are omnipresent. It is recommended that both ALP and Zn be measured together in milk to diagnose buffalo SCM, irrespective of etiology.

  3. Norrie disease: linkage analysis using a 4.2-kb RFLP detected by a human ornithine aminotransferase cDNA probe.

    Science.gov (United States)

    Ngo, J T; Bateman, J B; Cortessis, V; Sparkes, R S; Mohandas, T; Inana, G; Spence, M A

    1989-05-01

    Previous study has shown that the usual DNA marker for Norrie disease, the L1.28 probe which identifies the DXS7 locus, can recombine with the disease locus. In this study, we used a human ornithine aminotransferase (OAT) cDNA which detects OAT-related DNA sequences mapped to the same region on the X chromosome as that of the L1.28 probe to investigate the family with Norrie disease who exhibited the recombinational event. When genomic DNA from this family was digested with the PvuII restriction endonuclease, we found a restriction fragment length polymorphism (RFLP) of 4.2 kb in size. This fragment was absent in the affected males and cosegregated with the disease locus; we calculated a lod score of 0.602, at theta = 0.00. No deletion could be detected by chromosomal analysis or on Southern blots with other enzymes. These results suggest that one of the OAT-related sequences on the X chromosome may be in close proximity to the Norrie disease locus and represent the first report which indicates that the OAT cDNA may be useful for the identification of carrier status and/or prenatal diagnosis.

  4. Serum Alanine Aminotransferase Levels within Normal Range Have Different Associations with Augmentation Index and Other Cardiometabolic Risk Factors in Nondrinkers and Drinkers: A Chinese Community-Based Analysis

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    Shihui Fu

    2017-01-01

    Full Text Available Background. To investigate whether serum alanine aminotransferase (ALT levels within normal range were associated with augmentation index (AIx and cardiometabolic risk factors in nondrinkers and drinkers in Chinese community-dwelling population. Methods. There were 4165 participants with serum ALT levels within normal range. Results. Alcohol drinking was observed in 1173 participants (28.2%. In multivariate analysis, serum ALT levels of nondrinkers were independently associated with age, sex, body mass index (BMI, hypertension, diabetes mellitus, diastolic blood pressure, triglyceride, low-density lipoprotein-cholesterol (LDL-c, and AIx, while serum ALT levels of drinkers were independently associated with age, sex, BMI, triglyceride, and LDL-c (p<0.05 for all. Conclusions. Associations of serum ALT levels within normal range with age, sex, body height and weight, and blood lipid were simultaneously present in participants with and without alcohol drinking, while associations of serum ALT levels within normal range with AIx, blood pressure, and glucose were seen in nondrinkers rather than in drinkers. These findings not only provide the evidence that serum ALT levels, even within the normal range, have different associations with arteriosclerosis and cardiometabolic risk factors in nondrinkers and drinkers but also are helpful in understanding the underlying pathophysiologic mechanisms linking the hepatic function to arteriosclerosis and cardiometabolic risk factors.

  5. The antioxidant effects of vitamin C on liver enzymes: aspartate aminotransferase, alanine aminotranferease, alkaline phosphatase and gamma-glutamyltransferase activities in rats under Paraquat insult

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    Benjamin Nnamdi Okolonkwo

    2013-06-01

    Full Text Available Paraquat (PQ is a bipyridylium herbicide; applied around trees in orchards and between crop rows to control broad-leaved and grassy weeds. Its oxidation results in the formation of superoxides which causes damage to cellular components. In this study, we determined the antioxidant effect vitamin C has on the liver enzymes [aspartate aminotransferase (SGOT, alanine aminotranferease (SGPT, alkaline phosphatase (ALP, and gamma-glutamyltransferase (GGT] of rats under this toxic insult. Male rats in groups (A, B, C and D were intraperitoneally injected with different sublethal increasing doses (0, 0.02, 0.04 and 0.06 g/kg body weigh of PQ respectively on monthly basis. Subsequently, the subgroups (A2, B2, C2 and D2 were given orally, 200 mg/L vitamin C, while the subgroups A1, B1, C1, and D1, received only water. Four animals per subgroup were decapitated on monthly basis and blood samples taken for enzyme assay. The parameters studied were - SGOT, SGPT, ALP and GGT - liver enzymes. The dose and time dependent PQ toxicity effect resulted in highly elevated Liver enzymes activities. The subgroups on vitamin C had significantly lower enzyme activities when compared to the same subgroups on only PQ insult. But the values were high when compared to the control subgroups (A1 and A2. These results were indication that vitamin C when given at moderate doses and maintained for a longer period could be a life saving adjunct to toxic insult.

  6. Identificação de ponto de corte no nível sérico da alanina aminotransferase para rastreamento da hepatite C em pacientes com insuficiência renal crônica em hemodiálise Identification of the cutoff value for serum alanine aminotransferase in hepatitis C screening of patients with chronic renal failure on hemodialysis

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    Ericson Cavalcanti Gouveia

    2004-02-01

    Full Text Available Pacientes com insuficiência renal crônica em hemodiálise apresentam níveis séricos mais baixos de alanina aminotransferase. Para estabelecer melhor ponto de corte nos níveis de ALT, no diagnóstico da hepatite C, avaliaram-se mensalmente, durante 6 meses os níveis desta enzima em 235 pacientes em hemodiálise, sendo excluídos aqueles que apresentassem média acima do limite superior da normalidade. O ponto de corte foi identificado através da construção de curva ROC. Entre 202 pacientes, 15 (7,4% apresentavam anti-VHC positivo e 187 (92,6% negativo, com média de ALT de 0,7 e de 0,5 do limite superior (p The patients with chronic renal failure in hemodialysis present low levels of serum alanine aminotransferases. In order to establish a better cutoff value for ALT in hepatitis C screening of hemodialysis patients, the ALT levels were measured monthly in 235 patients, being excluded those that presented average above the upper limit of normality. The cutoff value was identified by construction of a ROC curve (receiver operating characteristic. Among 202 patients, 15 (7.4% presented antibodies to hepatitis C virus (anti-HCV and 187 (92.6% were anti-HCV negative , with an ALT average of 0.7 and of 0.5 from ULN (p <0.0001, respectively. The better cutoff value for ALT was at 0.6 from ULN, with sensitivity of 67% and specificity of 75% in anti-HCV screening. These results suggest that ULN of ALT could be reduced for 60% from conventional limit, when we are evaluating patients with CRF in hemodialysis.

  7. Antibody responses against xenotropic murine leukemia virus-related virus envelope in a murine model.

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    Natalia Makarova

    2011-04-01

    Full Text Available Xenotropic murine leukemia virus-related virus (XMRV was recently discovered to be the first human gammaretrovirus that is associated with chronic fatigue syndrome and prostate cancer (PC. Although a mechanism for XMRV carcinogenesis is yet to be established, this virus belongs to the family of gammaretroviruses well known for their ability to induce cancer in the infected hosts. Since its original identification XMRV has been detected in several independent investigations; however, at this time significant controversy remains regarding reports of XMRV detection/prevalence in other cohorts and cell type/tissue distribution. The potential risk of human infection, coupled with the lack of knowledge about the basic biology of XMRV, warrants further research, including investigation of adaptive immune responses. To study immunogenicity in vivo, we vaccinated mice with a combination of recombinant vectors expressing codon-optimized sequences of XMRV gag and env genes and virus-like particles (VLP that had the size and morphology of live infectious XMRV.Immunization elicited Env-specific binding and neutralizing antibodies (NAb against XMRV in mice. The peak titers for ELISA-binding antibodies and NAb were 1:1024 and 1:464, respectively; however, high ELISA-binding and NAb titers were not sustained and persisted for less than three weeks after immunizations.Vaccine-induced XMRV Env antibody titers were transiently high, but their duration was short. The relatively rapid diminution in antibody levels may in part explain the differing prevalences reported for XMRV in various prostate cancer and chronic fatigue syndrome cohorts. The low level of immunogenicity observed in the present study may be characteristic of a natural XMRV infection in humans.

  8. Higher Ratio of Serum Alpha-Fetoprotein Could Predict Outcomes in Patients with Hepatitis B Virus-Associated Hepatocellular Carcinoma and Normal Alanine Aminotransferase.

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    Young-Il Kim

    Full Text Available The role of serum alpha-fetoprotein (AFP levels in the surveillance and diagnosis of hepatocellular carcinoma (HCC is controversial. The aim of this study was to investigate the value of serially measured serum AFP levels in HCC progression or recurrence after initial treatment.A total of 722 consecutive patients newly diagnosed with HCC and treated at the National Cancer Center, Korea, between January 2004 and December 2009 were enrolled. The AFP ratios between 4-8 weeks post-treatment and those at the time of HCC progression or recurrence were obtained. Multivariate logistic regression analysis was performed to correlate the post-treatment AFP ratios with the presence of HCC progression or recurrence.The etiology of HCC was related to chronic hepatitis B virus (HBV infection in 562 patients (77.8%, chronic hepatitis C virus (HCV infection in 74 (10.2%, and non-viral cause in 86 (11.9%. There was a significant decrease in serum AFP levels from the baseline to 4 to 8 weeks after treatment (median AFP, 319.6 ng/mL vs. 49.6 ng/mL; p 1.0 was an independently associated with HCC progression or recurrence. Among the different causes of HCC analyzed, this association was significant only for HCC related to chronic hepatitis B (p< 0.001 and non-viral causes (p<0.05, and limited only to patients who had normal alanine aminotransferase (ALT levels.Serial measurements of serum AFP ratios could be helpful in detecting progression or recurrence in treated patients with HBV-HCC and normal ALT.

  9. Higher Ratio of Serum Alpha-Fetoprotein Could Predict Outcomes in Patients with Hepatitis B Virus-Associated Hepatocellular Carcinoma and Normal Alanine Aminotransferase

    Science.gov (United States)

    Park, Joong-Won

    2016-01-01

    Background The role of serum alpha-fetoprotein (AFP) levels in the surveillance and diagnosis of hepatocellular carcinoma (HCC) is controversial. The aim of this study was to investigate the value of serially measured serum AFP levels in HCC progression or recurrence after initial treatment. Methods A total of 722 consecutive patients newly diagnosed with HCC and treated at the National Cancer Center, Korea, between January 2004 and December 2009 were enrolled. The AFP ratios between 4–8 weeks post-treatment and those at the time of HCC progression or recurrence were obtained. Multivariate logistic regression analysis was performed to correlate the post-treatment AFP ratios with the presence of HCC progression or recurrence. Results The etiology of HCC was related to chronic hepatitis B virus (HBV) infection in 562 patients (77.8%), chronic hepatitis C virus (HCV) infection in 74 (10.2%), and non-viral cause in 86 (11.9%). There was a significant decrease in serum AFP levels from the baseline to 4 to 8 weeks after treatment (median AFP, 319.6 ng/mL vs. 49.6 ng/mL; p 1.0 was an independently associated with HCC progression or recurrence. Among the different causes of HCC analyzed, this association was significant only for HCC related to chronic hepatitis B (p< 0.001) and non-viral causes (p<0.05), and limited only to patients who had normal alanine aminotransferase (ALT) levels. Conclusion Serial measurements of serum AFP ratios could be helpful in detecting progression or recurrence in treated patients with HBV-HCC and normal ALT. PMID:27304617

  10. Essential roles of aspartate aminotransferase 1 and vesicular glutamate transporters in β-cell glutamate signaling for incretin-induced insulin secretion.

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    Naoya Murao

    Full Text Available Incretins (GLP-1 and GIP potentiate insulin secretion through cAMP signaling in pancreatic β-cells in a glucose-dependent manner. We recently proposed a mechanistic model of incretin-induced insulin secretion (IIIS that requires two critical processes: 1 generation of cytosolic glutamate through the malate-aspartate (MA shuttle in glucose metabolism and 2 glutamate transport into insulin granules by cAMP signaling to promote insulin granule exocytosis. To directly prove the model, we have established and characterized CRISPR/Cas9-engineered clonal mouse β-cell lines deficient for the genes critical in these two processes: aspartate aminotransferase 1 (AST1, gene symbol Got1, a key enzyme in the MA shuttle, which generates cytosolic glutamate, and the vesicular glutamate transporters (VGLUT1, VGLUT2, and VGLUT3, gene symbol Slc17a7, Slc17a6, and Slc17a8, respectively, which participate in glutamate transport into secretory vesicles. Got1 knockout (KO β-cell lines were defective in cytosolic glutamate production from glucose and showed impaired IIIS. Unexpectedly, different from the previous finding that global Slc17a7 KO mice exhibited impaired IIIS from pancreatic islets, β-cell specific Slc17a7 KO mice showed no significant impairment in IIIS, as assessed by pancreas perfusion experiment. Single Slc17a7 KO β-cell lines also retained IIIS, probably due to compensatory upregulation of Slc17a6. Interestingly, triple KO of Slc17a7, Slc17a6, and Slc17a8 diminished IIIS, which was rescued by exogenously introduced wild-type Slc17a7 or Slc17a6 genes. The present study provides direct evidence for the essential roles of AST1 and VGLUTs in β-cell glutamate signaling for IIIS and also shows the usefulness of the CRISPR/Cas9 system for studying β-cells by simultaneous disruption of multiple genes.

  11. Longitudinal association of obesity, metabolic syndrome and diabetes with risk of elevated aminotransferase levels in a cohort of Mexican health workers.

    Science.gov (United States)

    Flores, Yvonne N; Auslander, Allyn; Crespi, Catherine M; Rodriguez, Michael; Zhang, Zuo-Feng; Durazo, Francisco; Salmerón, Jorge

    2016-05-01

    In Mexico, chronic liver disease have been increasingly found along with the rapidly growing prevalence of obesity, diabetes and metabolic syndrome (MS). We aimed to investigate the longitudinal association between these three factors and risk of elevated alanine aminotransferase (ALT) levels (>40 U/L), a marker for liver damage, in a cohort of Mexican adults. Data were obtained from two separate waves of the Mexican Health Worker Cohort Study: Wave 1 (2004-2006) and Wave 2 (2011-2013). Unconditional logistic regression models were employed to determine the cross-sectional and longitudinal association between these risk factors and elevated ALT levels. The prevalence of elevated ALT was significantly higher among men, individuals aged under 60 years, those who were overweight or obese, diabetic, with MS or heavy/binge drinkers. The longitudinal results indicated that weight gain between waves that resulted in a change in body mass index, along with remaining overweight or obese, were significantly associated with an increased risk of elevated ALT levels. A significantly increased risk of developing elevated ALT was also observed among those who acquired diabetes or MS from Wave 1 to Wave 2. Weight gain and acquiring diabetes or MS are associated with a significant risk of having elevated ALT. These results, within the context of the rapid increase in global obesity rates, call urgently for programs to help to prevent chronic liver disease. © 2016 Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.

  12. Mechanism of inactivation of γ-aminobutyric acid aminotransferase by (1S,3S)-3-amino-4-difluoromethylene-1-cyclopentanoic acid (CPP-115).

    Science.gov (United States)

    Lee, Hyunbeom; Doud, Emma H; Wu, Rui; Sanishvili, Ruslan; Juncosa, Jose I; Liu, Dali; Kelleher, Neil L; Silverman, Richard B

    2015-02-25

    γ-Aminobutyric acid aminotransferase (GABA-AT) is a pyridoxal 5'-phosphate (PLP)-dependent enzyme that degrades GABA, the principal inhibitory neurotransmitter in mammalian cells. When the concentration of GABA falls below a threshold level, convulsions can occur. Inhibition of GABA-AT raises GABA levels in the brain, which can terminate seizures as well as have potential therapeutic applications in treating other neurological disorders, including drug addiction. Among the analogues that we previously developed, (1S,3S)-3-amino-4-difluoromethylene-1-cyclopentanoic acid (CPP-115) showed 187 times greater potency than that of vigabatrin, a known inactivator of GABA-AT and approved drug (Sabril) for the treatment of infantile spasms and refractory adult epilepsy. Recently, CPP-115 was shown to have no adverse effects in a Phase I clinical trial. Here we report a novel inactivation mechanism for CPP-115, a mechanism-based inactivator that undergoes GABA-AT-catalyzed hydrolysis of the difluoromethylene group to a carboxylic acid with concomitant loss of two fluoride ions and coenzyme conversion to pyridoxamine 5'-phosphate (PMP). The partition ratio for CPP-115 with GABA-AT is about 2000, releasing cyclopentanone-2,4-dicarboxylate (22) and two other precursors of this compound (20 and 21). Time-dependent inactivation occurs by a conformational change induced by the formation of the aldimine of 4-aminocyclopentane-1,3-dicarboxylic acid and PMP (20), which disrupts an electrostatic interaction between Glu270 and Arg445 to form an electrostatic interaction between Arg445 and the newly formed carboxylate produced by hydrolysis of the difluoromethylene group in CPP-115, resulting in a noncovalent, tightly bound complex. This represents a novel mechanism for inactivation of GABA-AT and a new approach for the design of mechanism-based inactivators in general.

  13. Crystal structure of the S187F variant of human liver alanine: Aminotransferase associated with primary hyperoxaluria type I and its functional implications

    Science.gov (United States)

    Oppici, Elisa; Fodor, Krisztian; Paiardini, Alessandro; Williams, Chris; Voltattorni, Carla Borri; Wilmanns, Matthias; Cellini, Barbara

    2013-01-01

    The substitution of Ser187, a residue located far from the active site of human liver peroxisomal alanine:glyoxylate aminotransferase (AGT), by Phe gives rise to a variant associated with primary hyperoxaluria type I. Unexpectedly, previous studies revealed that the recombinant form of S187F exhibits a remarkable loss of catalytic activity, an increased pyridoxal 5′-phosphate (PLP) binding affinity and a different coenzyme binding mode compared with normal AGT. To shed light on the structural elements responsible for these defects, we solved the crystal structure of the variant to a resolution of 2.9 Å. Although the overall conformation of the variant is similar to that of normal AGT, we noticed: (i) a displacement of the PLP-binding Lys209 and Val185, located on the re and si side of PLP, respectively, and (ii) slight conformational changes of other active site residues, in particular Trp108, the base stacking residue with the pyridine cofactor moiety. This active site perturbation results in a mispositioning of the AGT-pyridoxamine 5′-phosphate (PMP) complex and of the external aldimine, as predicted by molecular modeling studies. Taken together, both predicted and observed movements caused by the S187F mutation are consistent with the following functional properties of the variant: (i) a 300- to 500-fold decrease in both the rate constant of L-alanine half-transamination and the kcat of the overall transamination, (ii) a different PMP binding mode and affinity, and (iii) a different microenvironment of the external aldimine. Proposals for the treatment of patients bearing S187F mutation are discussed on the basis of these results. Proteins 2013; 81:1457–1465. © 2013 Wiley Periodicals, Inc. PMID:23589421

  14. High serum carotenoids are associated with lower risk for developing elevated serum alanine aminotransferase among Japanese subjects: the Mikkabi cohort study.

    Science.gov (United States)

    Sugiura, Minoru; Nakamura, Mieko; Ogawa, Kazunori; Ikoma, Yoshinori; Yano, Masamichi

    2016-04-01

    Many recent studies have shown that antioxidant vitamins and/or carotenoids may reduce liver disease, but this association has not been well established with thorough longitudinal cohort studies. The objective of this study was to longitudinally investigate whether serum carotenoids at baseline are associated with the risk of developing elevated serum alanine aminotransferase (ALT) among Japanese subjects. We conducted a follow-up study of 1073 males and females aged between 30 and 79 years at baseline from the Mikkabi prospective cohort study. Those who participated in the baseline study and completed follow-up surveys were examined longitudinally. Exclusions included excessive alcohol consumption (≥60 g alcohol/d), hepatitis B and C and having a history of medication use for liver disease. A cohort of 213 males and 574 females free of elevated serum ALT (>30 IU/ml) at baseline was studied. Over a mean follow-up period of 7·4 (sd 3·1) years, thirty-one males and forty-nine females developed new elevated serum ALT. After adjustments for confounders, the hazard ratios for elevated serum ALT in the highest tertiles of basal serum β-carotene, β-cryptoxanthin and total provitamin A carotenoids against the lowest tertiles were 0·43 (95 % CI 0·22, 0·81), 0·51 (CI 0·27, 0·94) and 0·52 (CI 0·28, 0·97), respectively. For α-carotene and lycopene, borderline reduced risks were also observed; however, these were not significant. Our results further support the hypothesis that antioxidant carotenoids, especially provitamin A carotenoids, might help prevent earlier pathogenesis of non-alcoholic liver disease in Japanese subjects.

  15. Liver biomarker and in vitro assessment confirm the hepatic origin of aminotransferase elevations lacking histopathological correlate in beagle dogs treated with GABAA receptor antagonist NP260

    International Nuclear Information System (INIS)

    Harrill, Alison H.; Eaddy, John S.; Rose, Kelly; Cullen, John M.; Ramanathan, Lakshmi; Wanaski, Stephen; Collins, Stephen; Ho, Yu; Watkins, Paul B.; LeCluyse, Edward L.

    2014-01-01

    NP260 was designed as a first-in-class selective antagonist of α4-subtype GABA A receptors that had promising efficacy in animal models of pain, epilepsy, psychosis, and anxiety. However, development of NP260 was complicated following a 28-day safety study in dogs in which pronounced elevations of serum aminotransferase levels were observed, although there was no accompanying histopathological indication of hepatocellular injury. To further investigate the liver effects of NP260, we assayed stored serum samples from the 28-day dog study for liver specific miRNA (miR-122) as well as enzymatic biomarkers glutamate dehydrogenase and sorbitol dehydrogenase, which indicate liver necrosis. Cytotoxicity assessments were conducted in hepatocytes derived from dog, rat, and human liver samples to address the species specificity of the liver response to NP260. All biomarkers, except ALT, returned toward baseline by Day 29 despite continued drug treatment, suggesting adaptation to the initial injury. In vitro analysis of the toxicity potential of NP260 to primary hepatocytes indicated a relative sensitivity of dog > human > rat, which may explain, in part, why the liver effects were not evident in the rodent safety studies. Taken together, the data indicate that a diagnostic biomarker approach, coupled with sensitive in vitro screening strategies, may facilitate interpretation of toxicity potential when an adaptive event masks the underlying toxicity. - Highlights: • NP260 caused ALT elevations in dogs without evidence of hepatocellular injury. • SDH, GLDH, and miRNA-122 elevations occurred, confirming hepatocellular necrosis. • NP260 toxicity is greater in dog and human hepatocytes than in rat hepatocytes. • Species sensitivity may explain why the rodent studies failed to indicate risk. • Diagnostic biomarkers and hepatocyte studies aid interpretation of hepatotoxicity

  16. Evaluation of the effects of a VEGFR-2 inhibitor compound on alanine aminotransferase gene expression and enzymatic activity in the rat liver.

    Science.gov (United States)

    Fuentealba, Carmen; Bera, Monali; Jessen, Bart; Sace, Fred; Stevens, Greg J; Trajkovic, Dusko; Yang, Amy H; Evering, Winston

    2011-08-17

    Traditional assessment of drug-induced hepatotoxicity includes morphological examination of the liver and evaluation of liver enzyme activity in serum. The objective of the study was to determine the origin of drug-related elevation in serum alanine aminotransferase (ALT) activity in the absence of morphologic changes in the liver by utilizing molecular and immunohistochemical techniques. Sixteen female Sprague-Dawley rats were divided into 2 groups (control and treated, n = 4 per group) and treated rats were dosed orally twice daily (400 mg/kg/day) for 7 days with a VEGFR-2 compound (AG28262), which in a previous study caused ALT elevation without morphological changes. Serum of both treated and control animals were evaluated on day 3 of treatment and at day 8. Three separate liver lobes (caudate, right medial, and left lateral) were examined for determination of ALT tissue activity, ALT gene expression and morphological changes. ALT activity was significantly (p < 0.01) elevated on day 3 and further increased on day 8. Histologic changes or increase in TUNEL and caspase3 positive cells were not observed in the liver lobes examined. ALT gene expression in the caudate lobe was significantly up-regulated by 63%. ALT expression in the left lateral lobe was not significantly affected. Statistically significant increased liver ALT enzymatic activity occurred in the caudate (96%) and right medial (41%) lobes but not in the left lateral lobe. AG28262, a VEFG-r2 inhibitor, causes an increase in serum ALT, due in part to both gene up-regulation. Differences between liver lobes may be attributable to differential distribution of blood from portal circulation. Incorporation of molecular data, such as gene and protein expression, and sampling multiple liver lobes may shed mechanistic insight to the evaluation of hepatotoxicity.

  17. Three-dimensional alginate spheroid culture system of murine osteosarcoma.

    Science.gov (United States)

    Akeda, Koji; Nishimura, Akinobu; Satonaka, Haruhiko; Shintani, Ken; Kusuzaki, Katsuyuki; Matsumine, Akihiko; Kasai, Yuichi; Masuda, Koichi; Uchida, Atsumasa

    2009-11-01

    Osteosarcoma (OS) is the most common primary malignant tumor of the bone and often forms pulmonary metastases, which are the most important prognostic factor. For further elucidation of the mechanism underlying the progression and metastasis of human OS, a culture system mimicking the microenvironment of the tumor in vivo is needed. We report a novel three-dimensional (3D) alginate spheroid culture system of murine osteosarcoma. Two different metastatic clones, the parental Dunn and its derivative line LM8, which has a higher metastatic potential to the lungs, were encapsulated in alginate beads to develop the 3D culture system. The beads containing murine OS cells were also transplanted into mice to determine their metastatic potential in vivo. In this culture system, murine OS cells encapsulated in alginate beads were able to grow in a 3D structure with cells detaching from the alginate environment. The number of detaching cells was higher in the LM8 cell line than the Dunn cell line. In the in vivo alginate bead transplantation model, the rate of pulmonary metastasis was higher with LM8 cells compared with that of Dunn cells. The cell characteristics and kinetics in this culture system closely reflect the original malignant potential of the cells in vivo.

  18. Enhancement of tumor radioresponse by combined chemotherapy in murine hepatocarcinoma

    International Nuclear Information System (INIS)

    Seong, Jin Sil; Kim, Sung Hee; Suh, Chang Ok

    2000-01-01

    The purpose of this study was to identify drugs that can enhance radioresponse of murine hepatocarcinoma. C3H/HeJ mice bearing 8 mm tumors of murine hepatocarcinoma, HCa-l, were treated with 25 Gy radiation and one of the following drugs: 5-Fu, 150 mg/kg; adriamycin, 8 mg/kg; cisplatin, 6 mg/kg; paclitaxel, 40 mg/kg; and gemcitabine, 50 mg/kg. Tumor response to the treatment was determined by tumor growth delay assay and by enhancement factor. Apoptotic level was assessed in tissue sections. Expression of regulating molecules was analyzed by western blotting for p53, 8c1-2, Sax, Bel-XL, Bd-XS, and p21 WAF1/CIP1 . Among the drugs tested, only gemcitabine enhanced the antitumor effect of radiation, with enhancement factor of 1.6. Induction of apoptosis by a combination of gerncitabine and radiation was shown as only additive level. In analysis of radiation-induced expression of regulating molecules, the most significant change by combining gemcitabine was activation of p21 WAF1/CIP1 . Gemcitabine is the first drug showing an enhancement of radioresponse in murine hepatocarcinoma, when combined with radiation. The key element of enhancement is thought to be p21 WAF1/CIP1

  19. Enhancement of tumor radioresponse by combined chemotherapy in murine hepatocarcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Seong, Jin Sil; Kim, Sung Hee; Suh, Chang Ok [College of Medicine, Yonsei Univ., Seoul (Korea, Republic of)

    2000-12-01

    The purpose of this study was to identify drugs that can enhance radioresponse of murine hepatocarcinoma. C3H/HeJ mice bearing 8 mm tumors of murine hepatocarcinoma, HCa-l, were treated with 25 Gy radiation and one of the following drugs: 5-Fu, 150 mg/kg; adriamycin, 8 mg/kg; cisplatin, 6 mg/kg; paclitaxel, 40 mg/kg; and gemcitabine, 50 mg/kg. Tumor response to the treatment was determined by tumor growth delay assay and by enhancement factor. Apoptotic level was assessed in tissue sections. Expression of regulating molecules was analyzed by western blotting for p53, 8c1-2, Sax, Bel-XL, Bd-XS, and p21{sup WAF1/CIP1}. Among the drugs tested, only gemcitabine enhanced the antitumor effect of radiation, with enhancement factor of 1.6. Induction of apoptosis by a combination of gerncitabine and radiation was shown as only additive level. In analysis of radiation-induced expression of regulating molecules, the most significant change by combining gemcitabine was activation of p21 {sup WAF1/CIP1}. Gemcitabine is the first drug showing an enhancement of radioresponse in murine hepatocarcinoma, when combined with radiation. The key element of enhancement is thought to be p21{sup WAF1/CIP1}.

  20. The Role of the MHV Receptor and Related Glycoproteins in Murine Hepatitis Virus Infection of Murine Cell Lines

    Science.gov (United States)

    1995-04-13

    vaccinia virus-T7 RNA polymerase s y stem for e xpression of target genes . Mol . Cell . BioI . 7 : 2538-2544 . Gagneten , S ., Gout , 0 ., Dubois-Dalcq...glycoprotein. These results showed f or the first time that two murine CEA- related genes can be co-expressed in some cell lines from inbred mice...49 Southern Hybridization ................ . ............ 50 Subcloning of PCR Products and Gene Cloning ........ 51 Growth

  1. Alanine-glyoxylate aminotransferase 2 (AGXT2 polymorphisms have considerable impact on methylarginine and β-aminoisobutyrate metabolism in healthy volunteers.

    Directory of Open Access Journals (Sweden)

    Anja Kittel

    Full Text Available Elevated plasma concentrations of asymmetric (ADMA and symmetric (SDMA dimethylarginine have repeatedly been linked to adverse clinical outcomes. Both methylarginines are substrates of alanine-glyoxylate aminotransferase 2 (AGXT2. It was the aim of the present study to simultaneously investigate the functional relevance and relative contributions of common AGXT2 single nucleotide polymorphisms (SNPs to plasma and urinary concentrations of methylarginines as well as β-aminoisobutyrate (BAIB, a prototypic substrate of AGXT2. In a cohort of 400 healthy volunteers ADMA, SDMA and BAIB concentrations were determined in plasma and urine using HPLC-MS/MS and were related to the coding AGXT2 SNPs rs37369 (p.Val140Ile and rs16899974 (p.Val498Leu. Volunteers heterozygous or homozygous for the AGXT2 SNP rs37369 had higher SDMA plasma concentrations by 5% and 20% (p = 0.002 as well as higher BAIB concentrations by 54% and 146%, respectively, in plasma and 237% and 1661%, respectively, in urine (both p<0.001. ADMA concentrations were not affected by both SNPs. A haplotype analysis revealed that the second investigated AGXT2 SNP rs16899974, which was not significantly linked to the other AGXT2 SNP, further aggravates the effect of rs37369 with respect to BAIB concentrations in plasma and urine. To investigate the impact of the amino acid exchange p.Val140Ile, we established human embryonic kidney cell lines stably overexpressing wild-type or mutant (p.Val140Ile AGXT2 protein and assessed enzyme activity using BAIB and stable-isotope labeled [²H₆]-SDMA as substrate. In vitro, the amino acid exchange of the mutant protein resulted in a significantly lower enzyme activity compared to wild-type AGXT2 (p<0.05. In silico modeling of the SNPs indicated reduced enzyme stability and substrate binding. In conclusion, SNPs of AGXT2 affect plasma as well as urinary BAIB and SDMA concentrations linking methylarginine metabolism to the common genetic trait of hyper

  2. Performance of an Optimized Paper-Based Test for Rapid Visual Measurement of Alanine Aminotransferase (ALT in Fingerstick and Venipuncture Samples.

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    Sidhartha Jain

    Full Text Available A paper-based, multiplexed, microfluidic assay has been developed to visually measure alanine aminotransferase (ALT in a fingerstick sample, generating rapid, semi-quantitative results. Prior studies indicated a need for improved accuracy; the device was subsequently optimized using an FDA-approved automated platform (Abaxis Piccolo Xpress as a comparator. Here, we evaluated the performance of the optimized paper test for measurement of ALT in fingerstick blood and serum, as compared to Abaxis and Roche/Hitachi platforms. To evaluate feasibility of remote results interpretation, we also compared reading cell phone camera images of completed tests to reading the device in real time.96 ambulatory patients with varied baseline ALT concentration underwent fingerstick testing using the paper device; cell phone images of completed devices were taken and texted to a blinded off-site reader. Venipuncture serum was obtained from 93/96 participants for routine clinical testing (Roche/Hitachi; subsequently, 88/93 serum samples were captured and applied to paper and Abaxis platforms. Paper test and reference standard results were compared by Bland-Altman analysis.For serum, there was excellent agreement between paper test and Abaxis results, with negligible bias (+4.5 U/L. Abaxis results were systematically 8.6% lower than Roche/Hitachi results. ALT values in fingerstick samples tested on paper were systematically lower than values in paired serum tested on paper (bias -23.6 U/L or Abaxis (bias -18.4 U/L; a correction factor was developed for the paper device to match fingerstick blood to serum. Visual reads of cell phone images closely matched reads made in real time (bias +5.5 U/L.The paper ALT test is highly accurate for serum testing, matching the reference method against which it was optimized better than the reference methods matched each other. A systematic difference exists between ALT values in fingerstick and paired serum samples, and can be

  3. Evaluation of the aspartate aminotransferase/platelet ratio index and enhanced liver fibrosis tests to detect significant fibrosis due to chronic hepatitis C.

    Science.gov (United States)

    Petersen, John R; Stevenson, Heather L; Kasturi, Krishna S; Naniwadekar, Ashutosh; Parkes, Julie; Cross, Richard; Rosenberg, William M; Xiao, Shu-Yuan; Snyder, Ned

    2014-04-01

    The assessment of liver fibrosis in chronic hepatitis C patients is important for prognosis and making decisions regarding antiviral treatment. Although liver biopsy is considered the reference standard for assessing hepatic fibrosis in patients with chronic hepatitis C, it is invasive and associated with sampling and interobserver variability. Serum fibrosis markers have been utilized as surrogates for a liver biopsy. We completed a prospective study of 191 patients in which blood draws and liver biopsies were performed on the same visit. Using liver biopsies the sensitivity, specificity, and negative and positive predictive values for both aspartate aminotransferase/platelet ratio index (APRI) and enhanced liver fibrosis (ELF) were determined. The patients were divided into training and validation patient sets to develop and validate a clinically useful algorithm for differentiating mild and significant fibrosis. The area under the ROC curve for the APRI and ELF tests for the training set was 0.865 and 0.880, respectively. The clinical sensitivity in separating mild (F0-F1) from significant fibrosis (F2-F4) was 80% and 86.0% with a clinical specificity of 86.7% and 77.8%, respectively. For the validation sets the area under the ROC curve for the APRI and ELF tests was, 0.855 and 0.780, respectively. The clinical sensitivity of the APRI and ELF tests in separating mild (F0-F1) from significant (F2-F4) fibrosis for the validation set was 90.0% and 70.0% with a clinical specificity of 73.3% and 86.7%, respectively. There were no differences between the APRI and ELF tests in distinguishing mild from significant fibrosis for either the training or validation sets (P=0.61 and 0.20, respectively). Using APRI as the primary test followed by ELF for patients in the intermediate zone, would have decreased the number of liver biopsies needed by 40% for the validation set. Overall, use of our algorithm would have decreased the number of patients who needed a liver biopsy

  4. The Enantiomers of 4-Amino-3-fluorobutanoic Acid as Substrates for γ-Aminobutyric Acid Aminotransferase. Conformational Probes for GABA Binding†

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    Clift, Michael; Ji, Haitao; Deniau, Gildas P.; O’Hagan, David; Silverman, Richard B.

    2008-01-01

    γ-Aminobutyric acid aminotransferase (GABA-AT), a pyridoxal 5’-phosphate dependent enzyme, catalyzes the degradation of the inhibitory neurotransmitter γ-aminobutyric acid (GABA) to succinic semialdehyde with concomitant conversion of pyridoxal 5’-phosphate (PLP) to pyridoxamine 5’-phosphate (PMP). The enzyme then catalyzes the conversion of α-ketoglutarate to the excitatory neurotransmitter L-glutamate. Racemic 4-amino-3-fluorobutanoic acid (3-F-GABA) was shown previously to act as a substrate for GABA-AT, not for transamination, but for HF elimination. Here we report studies of the reaction catalyzed by GABA-AT on (R)- and (S)-3-F-GABA. Neither enantiomer is a substrate for transamination. Very little elimination from the (S)-enantiomer was detected using a coupled enzyme assay; The rate of elimination of HF from the (R)-enantiomer is at least 10 times greater than that for the (S)-enantiomer. The (R)-enantiomer is about 20 times more efficient as a substrate for GABA-AT catalyzed HF elimination than GABA is a substrate for transamination. The (R)-enantiomer also inhibits the transamination of GABA 10 times more effectively than the (S)-enantiomer. Using a combination of computer modeling and the knowledge that vicinal C-F and C-NH3+ bonds have a strong preference to align gauche rather than anti to each other, it is concluded that on binding of free 3-F-GABA to GABA-AT the optimal conformation places the C-NH3+ and C-F bonds gauche in the (R)-enantiomer but anti in the (S)-enantiomer. Furthermore, the dynamic binding process and the bioactive conformation of GABA bound to GABA-AT have been inferred based on the different biological behavior of the two enantiomers of 3-F-GABA when they bind to the enzyme. The present study suggests that the C-F bond can be utilized as a conformational probe to explore the dynamic binding process and provide insight into the bioactive conformation of substrates, which cannot be easily determined by other biophysical

  5. Effect of Capreolus capreolus and Sus scrofa excreta on alanine aminotransferase activity in Glechoma hederacea leaves in conditions of Cd pollution

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    O. M. Vasilyuk

    2015-06-01

    Full Text Available The paper reflects the analysis of Cd impact on the total activity (nM pyruvic acid/ml s of alanine aminotransferase (ALT, EC 2.6.1.2 nitrogen metabolism and the content (mg/ml of water-soluble protein fraction (albumin in Glechoma hederacea L. leaves subject, which dominated in the research area (natural floodplain oak with Stellaria holostea L.. Cd was introduced in the form of salts Cd(NO32 in the concentrations of 0.25, 1.25 and 2.50 g/m2, equivalent to Cd in 1, 5 and 10 doses of MAC. The content of doses of MAC of Cd (5 mg/kg soil was taken into account during introduction. We observed the inhibition of the activity of ALT 3–4 times (with adding the Cd salts at a dose of 1 and 5 МAС compared to controls (area without pollution of Cd and excreta of mammals. This stress reaction took place in the protein complex as well. Thus, albumin content was equal to 72% and 80% (with Cd 1 and 5 MAC compared to control (the area without pollution and excretory functions of mammals. It proved nonspecific response to stress. Using excreta of Capreolus capreolus L. and Sus scrofa L. shows the reduction of Cd effects and increasing the metabolic activity of ALT by 41% and 105%, respectively (with adding of Cd 1 MAC compared to control (pollution by Cd at a dose 1 MAC. The effect of Cd 5 MAC is offset (only with the introduction of C. capreolus excreta compared to control (pollution by Cd at a dose 5 MAC. Normalization of the albumin content (with adding of Cd 1 and 5 MAC compared to control (сontrol of Cd at a dose 1 MAC and сontrol of Cd at a dose 5 MAC with using of excreta of C. capreolus was observed. In conditions of Cd at a doze 10 MAC the ALT activity was reduced 2 times with the introduction of excreta of C. capreolus as S. scrofa compared to control (Cd at a dose 10 MAC. The introduction of excreta of S. scrofa compared with C. capreolus restored the albumin content by 10% to the control. Thus, the feasibility of using different biological

  6. Independent predictive factors for significant liver histological changes in patients with HBeAg-positive high-viral-load chronic HBV infection and a normal alanine aminotransferase level

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    LI Qiang

    2016-07-01

    Full Text Available Objective To investigate the independent predictive factors for significant liver histological changes (SLHCs in patients with HBeAg-positive high-viral-load chronic hepatitis B virus (HBV infection and a normal alanine aminotransferase (ALT level. MethodsA retrospective analysis was performed on the clinical data of 116 previously untreated patients with HBeAg-positive high-viral-load (HBV DNA≥105 copies/ml chronic HBV infection and a normal ALT level (<50 U/L who were hospitalized in Shanghai Public Health Clinical Center Affiliated to Fudan University from June 2013 to August 2015. The definition of SLHCs was inflammation ≥G2 and/or fibrosis≥S2. The t-test or Mann-Whitney U rank sum test was used for comparison of continuous data between groups, and the chi-square test was used for comparison of categorical data between groups. Univariate and multivariate regression analyses were used to determine independent predictive factors for SLHCs. ResultsOf all the 116 patients, 47(40.5% had SLHCs. The multivariate analysis showed that age (OR=2.828, P<0.05, ALT (OR=1.011, P<0.05, and gamma-glutamyl transpeptidase (GGT (OR=1.089, P<0.05 were independent predictors for SLHCs in patients with HBeAg-positive high-viral-load chronic HBV infection and a normal ALT level. The patients aged ≤30 years had a significantly lower incidence rate of SLHCs than those aged>30 years (21.6% vs 49.4%, χ2=6.42, P=0.015, the patients with ALT ≤30 U/L had a significantly lower incidence rate of SLHCs than those with 30 U/L<ALT≤50 U/L (17.6% vs 50.0%, χ2=19.86, P<0.001, and the patients with GGT≤40 U/L had a significantly lower incidence rate of SLHCs than those with GGT>40 U/L (28.8% vs 66.7%, χ2=28.63, P<0.001. ConclusionIn patients with HBeAg-positive high-viral-load chronic HBV infection and a normal ALT level, those with an age of>30 years, ALT>30 U/L, and GGT>40 U/L tend to develop SLHCs and need liver biopsy.

  7. Safety and efficacy of the immunosuppressive agent 6-tioguanine in murine model of acute and chronic colitis

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    van Bodegraven Adriaan A

    2011-05-01

    Full Text Available Abstract Background Oral thiopurines are effective and widely used in treatment of inflammatory bowel disease (IBD in humans, although their use is limited due the development of adverse events. Here, we examine the efficacy and toxicity of oral treatment with 6-tioguanine (6-TG and azathioprine (AZA in a murine model of IBD. Methods We induced acute or chronic colitis in BALB/c mice by one or four cycles of 3% dextran sulphate sodium (DSS, respectively. Mice were treated by daily gavages of various dosages of 6-tioguanine, azathioprine, or by phosphate buffered saline (PBS starting the first day of DSS or after two cycles of DSS, respectively. We monitored the efficacy and toxicity by measuring the weight change and serum alanine aminotransferase (ALT activity and by disease severity and histology, at the end of the experiment. Moreover, we measured cytokine production after colon fragment cultivation by enzyme-linked immunoabsorbent assay and numbers of apoptotic cells in the spleen by flow cytometry. Results 6-TG is effective in the treatment of acute DSS-induced colitis in a dose-dependent manner and 40 μg of 6-TG is significantly more effective in the treatment of acute colitis than both AZA and PBS. This effect is accompanied by decrease of IL-6 and IFN-γ production in colon. We did not observe histological abnormalities in liver samples from control (PBS or 6-TG treated mice. However, liver samples from most mice treated with AZA showed mild, yet distinct signs of hepatotoxicity. In chronic colitis, all thiopurine derivatives improved colitis, 20 μg of 6-TG per dose was superior. High doses of 6-TG led to significant weight loss at the end of the therapy, but none of the thiopurine derivatives increased levels of serum ALT. Both thiopurine derivatives reduced the proportion of apoptotic T helper cells, but a high production of both IL-6 and TGF-β was observed only in colon of AZA-treated mice. Conclusions Use of 6-TG in the treatment

  8. [Evaluation of Fusarium spp. pathogenicity in plant and murine models].

    Science.gov (United States)

    Forero-Reyes, Consuelo M; Alvarado-Fernández, Angela M; Ceballos-Rojas, Ana M; González-Carmona, Lady C; Linares-Linares, Melva Y; Castañeda-Salazar, Rubiela; Pulido-Villamarín, Adriana; Góngora-Medina, Manuel E; Cortés-Vecino, Jesús A; Rodríguez-Bocanegra, María X

    The genus Fusarium is widely recognized for its phytopathogenic capacity. However, it has been reported as an opportunistic pathogen in immunocompetent and immunocompromised patients. Thus, it can be considered a microorganism of interest in pathogenicity studies on different hosts. Therefore, this work evaluated the pathogenicity of Fusarium spp. isolates from different origins in plants and animals (murine hosts). Twelve isolates of Fusarium spp. from plants, animal superficial mycoses, and human superficial and systemic mycoses were inoculated in tomato, passion fruit and carnation plants, and in immunocompetent and immunosuppressed BALB/c mice. Pathogenicity tests in plants did not show all the symptoms associated with vascular wilt in the three plant models; however, colonization and necrosis of the vascular bundles, regardless of the species and origin of the isolates, showed the infective potential of Fusarium spp. in different plant species. Moreover, the pathogenicity tests in the murine model revealed behavioral changes. It was noteworthy that only five isolates (different origin and species) caused mortality. Additionally, it was observed that all isolates infected and colonized different organs, regardless of the species and origin of the isolates or host immune status. In contrast, the superficial inoculation test showed no evidence of epidermal injury or colonization. The observed results in plant and murine models suggest the pathogenic potential of Fusarium spp. isolates in different types of hosts. However, further studies on pathogenicity are needed to confirm the multihost capacity of this genus. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  9. Characterization of a Novel Murine Model to Study Zika Virus.

    Science.gov (United States)

    Rossi, Shannan L; Tesh, Robert B; Azar, Sasha R; Muruato, Antonio E; Hanley, Kathryn A; Auguste, Albert J; Langsjoen, Rose M; Paessler, Slobodan; Vasilakis, Nikos; Weaver, Scott C

    2016-06-01

    The mosquito-borne Zika virus (ZIKV) is responsible for an explosive ongoing outbreak of febrile illness across the Americas. ZIKV was previously thought to cause only a mild, flu-like illness, but during the current outbreak, an association with Guillain-Barré syndrome and microcephaly in neonates has been detected. A previous study showed that ZIKV requires murine adaptation to generate reproducible murine disease. In our study, a low-passage Cambodian isolate caused disease and mortality in mice lacking the interferon (IFN) alpha receptor (A129 mice) in an age-dependent manner, but not in similarly aged immunocompetent mice. In A129 mice, viremia peaked at ∼10(7) plaque-forming units/mL by day 2 postinfection (PI) and reached high titers in the spleen by day 1. ZIKV was detected in the brain on day 3 PI and caused signs of neurologic disease, including tremors, by day 6. Robust replication was also noted in the testis. In this model, all mice infected at the youngest age (3 weeks) succumbed to illness by day 7 PI. Older mice (11 weeks) showed signs of illness, viremia, and weight loss but recovered starting on day 8. In addition, AG129 mice, which lack both type I and II IFN responses, supported similar infection kinetics to A129 mice, but with exaggerated disease signs. This characterization of an Asian lineage ZIKV strain in a murine model, and one of the few studies reporting a model of Zika disease and demonstrating age-dependent morbidity and mortality, could provide a platform for testing the efficacy of antivirals and vaccines. © The American Society of Tropical Medicine and Hygiene.

  10. The effect of isotretinoin on triglycerides and liver aminotransferases Influência da isotretinoína nas transaminases hepáticas e triglicerídeos

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    Andreia Salezze Vieira

    2012-06-01

    Full Text Available BACKGROUND: Isotretinoin has been used to treat the most severe cases of acne; however, it may provoke adverse events in mucocutaneous and hepatic tissues, lead to alterations in lipid levels and cause teratogenicity. OBJECTIVE: The objective of this study was to evaluate the profile of changes in alanine aminotransferase (ALT, aspartate aminotransferase (AST and triglyceride levels in patients who had been treated with oral isotretinoin dispensed by the São Mateus/ES pharmacy for special drugs. METHODS: A retrospective, observational, longitudinal study was conducted by carrying out a secondary analysis of each patient's data. RESULTS: Of the 130 patients who received isotretinoin between January and December 2009, only 70 were actually treated for 3 months or more and handed in the results of their laboratory tests. Of these 70 patients, 39 (55.7% were female. The mean age of the women (23.9 years was higher than the mean age of the men (20.1 years. There was a statistically significant increase in the levels of triglycerides (87.01 ± 48.25 versus 105.32 ± 48.76 mg/dL, AST (20.44 ± 6.26 versus 24.38 ± 11.92 U/L and ALT (18.24 ± 8.31 versus 23.34 ± 20.03 U/L performed prior to and 3 months or more after oral isotretinoin treatment. After treatment with oral isotretinoin, triglyceride levels had increased beyond the normal range in 11% of the patients, while 8.6% had elevated AST levels and 7.3% had increased ALT levels. CONCLUSION: The results in this population show that the use of oral isotretinoin for the treatment of acne may result in altered triglyceride, AST and ALT levels. These findings are in accordance with data published previously in the scientific literature, confirming the need to monitor these patients.FUNDAMENTOS: A isotretinoína tem sido usada no tratamento dos casos mais graves de acne, embora possa induzir reações adversas nos tecidos mucocutâneos e hepáticos, alterações nos níveis lipídicos e

  11. Corn silk induced cyclooxygenase-2 in murine macrophages.

    Science.gov (United States)

    Kim, Kyung A; Shin, Hyun-Hee; Choi, Sang Kyu; Choi, Hye-Seon

    2005-10-01

    Stimulation of murine macrophages with corn silk induced cyclooxygenase (COX)-2 with secretion of PGE2. Expression of COX-2 was inhibited by pyrolidine dithiocarbamate (PDTC), and increased DNA binding by nuclear factor kappa B (NF-kappaB), indicating that COX-2 induction proceeds also via the NF-kappaB signaling pathway. A specific inhibitor of COX-2 decreased the expression level of inducible nitric oxide synthase (iNOS) stimulated by corn silk. PGE2 elevated the expression level of iNOS, probably via EP2 and EP4 receptors on the surface of the macrophages.

  12. Collagen-Induced Arthritis: A model for Murine Autoimmune Arthritis

    OpenAIRE

    Pietrosimone, K. M.; Jin, M.; Poston, B.; Liu, P.

    2015-01-01

    Collagen-induced arthritis (CIA) is a common autoimmune animal model used to study rheumatoid arthritis (RA). The development of CIA involves infiltration of macrophages and neutrophils into the joint, as well as T and B cell responses to type II collagen. In murine CIA, genetically susceptible mice (DBA/1J) are immunized with a type II bovine collagen emulsion in complete Freund’s adjuvant (CFA), and receive a boost of type II bovine collagen in incomplete Freund’s adjuvant (IFA) 21 days aft...

  13. Murine nephrotoxic nephritis as a model of chronic kidney disease

    DEFF Research Database (Denmark)

    Ougaard, M. K.E.; Kvist, P. H.; Jensen, H. E.

    2018-01-01

    Using the nonaccelerated murine nephrotoxic nephritis (NTN) as a model of chronic kidney disease (CKD) could provide an easily inducible model that enables a rapid test of treatments. Originally, the NTN model was developed as an acute model of glomerulonephritis, but in this study we evaluate...... progressive mesangial expansion and significant renal fibrosis within three weeks suggesting CKD development. CD1 and C57BL/6 females showed a similar disease progression, but female mice seemed more susceptible to NTS compared to male mice. The presence of albuminuria, GFR decline, mesangial expansion...

  14. Biological markers as predictors of radiosensitivity in syngeneic murine tumors

    International Nuclear Information System (INIS)

    Chang, Sei Kyung; Shin, Hyun Soo; Seong, Jin Sil; Kim, Sung Hee

    2006-01-01

    We investigated whether a relationship exists between tumor control dose 50 (TCD 50 ) or tumor growth delay (TGD) and radiation induced apoptosis (RIA) in syngeneic murine tumors. Also we investigated the biological markers that can predict radiosensitivity in murine tumor system through analysis of relationship between TCD 50 , TGD, RIA and constitutive expression levels of the genetic products regulating RIA. Syngeneic murine tumors such as ovarian adenocarcinoma, mammary carcinoma, squamous cell carcinoma, fibrosarcoma, hepatocarcinoma were used in this study. C3H/HeJ mice were bred and maintained in our specific pathogen free mouse colony and were 8 ∼ 12 weeks old when used for the experiments. The tumors, growing in the right hind legs of mice, were analyzed for TCD 50 , TGD, and RIA at 8 mm in diameter. The tumors were also analyzed for the constitutive expression levels of p53, p21 WAF1/CIP1 , BAX, Bcl-2, Bcl-x L , Bcl-x S , and p34. Correlation analysis was performed whether the level of RIA were correlated with TCD 50 or TGD, and the constitutive expression levels of genetic products regulating RIA were correlated with TCD 50 , TGD, RIA. The level of RIA showed a significant positive correlation (R = 0.922, ρ = 0.026) with TGD, and showed a trend to correlation (R = -0.848), marginally significant correlation with TCD 50 (ρ = 0.070). It indicates that tumors that respond to radiation with high percentage of apoptosis were more radiosensitive. The constitutive expression levels of p21 WAF1/CIP1 and p34 showed a significant correlation either with TCD 50 (R = 0.893, ρ = 0.041 and R = 0.904, ρ = 0.035) or with TGD (R = -0.922, ρ 0.026 and R = -0.890, ρ = 0.043). The tumors with high constitutive expression levels of p21 WAF1/CIP1 or p34 were less radiosensitive than those with low expression. Radiosensitivity may be predicted with the level of RIA in murine tumors. The constitutive expression levels of p21 WAF1/CIP1 or p34 can be used as biological

  15. Anticonvulsive evaluation of THIP in the murine pentylenetetrazole kindling model

    DEFF Research Database (Denmark)

    Simonsen, Charlotte; Boddum, Kim; von Schoubye, Nadia L

    2017-01-01

    . Evaluation of THIP as a potential anticonvulsant has given contradictory results in different animal models and for this reason, we reevaluated the anticonvulsive properties of THIP in the murine pentylenetetrazole (PTZ) kindling model. As loss of δ-GABAA R in the dentate gyrus has been associated...... the observed upregulation of δ-GABAA Rs. Even in the demonstrated presence of functional δ-GABAA Rs, THIP (0.5-4 mg/kg) showed no anticonvulsive effect in the PTZ kindling model using a comprehensive in vivo evaluation of the anticonvulsive properties....

  16. Production of antibodies which recognize opiate receptors on murine leukocytes

    Energy Technology Data Exchange (ETDEWEB)

    Carr, D.J.J.; Bost, K.L.; Blalock, J.E.

    1988-01-01

    An antibody has been developed which recognizes opiate receptors on cells of the immune system. This antibody blocks specific binding of the radiolabeled opiate receptor ligand, /sup 3/H-dihydromorphine, to receptors on murine splenocytes. Additionally, the anti-receptor antibody competes with ..beta..-endorphin, meta-enkephalin, and naloxone for the same binding site on the leukocytes. Moreover, the anti-receptor antibody possesses agonist activity similar to ..beta..-endorphin in suppressing cAMP production by lymphocytes. These results suggest the development of an antibody which recognizes classical opiate receptors on cells of the immune system.

  17. Murine cell glycolipids customization by modular expression of glycosyltransferases.

    Science.gov (United States)

    Cid, Emili; Yamamoto, Miyako; Buschbeck, Marcus; Yamamoto, Fumiichiro

    2013-01-01

    Functional analysis of glycolipids has been hampered by their complex nature and combinatorial expression in cells and tissues. We report an efficient and easy method to generate cells with specific glycolipids. In our proof of principle experiments we have demonstrated the customized expression of two relevant glycosphingolipids on murine fibroblasts, stage-specific embryonic antigen 3 (SSEA-3), a marker for stem cells, and Forssman glycolipid, a xenoantigen. Sets of genes encoding glycosyltansferases were transduced by viral infection followed by multi-color cell sorting based on coupled expression of fluorescent proteins.

  18. Studies on murine plasmocytoma treatment with mistletoe lectin I

    International Nuclear Information System (INIS)

    Raabe, F.; Storch, H.

    1987-01-01

    Mistletoe lectin I was tested in vivo and in vitro for its cytotoxic activity against murine plasmacytoma cells P3/X63-Ag8. As a result of this treatment, 30 to 60% of the BALB/c mice developed complete tumor regressions. 83% of the mice treated with mistletoe lectin I were resistant to viable tumor cell challenge after 100 days. The cytotoxic activity in vitro tested by 3 H-thymidine incorporation into P3/X63-Ag8 cells was very high. The rate was markedly reduced at concentrations up to 0.07 ng/ml. (author)

  19. Adrenaline influences the release of interleukin-6 from murine pituicytes

    DEFF Research Database (Denmark)

    Christensen, J D; Hansen, E W; Frederiksen, C

    1999-01-01

    In this study, we examined the effect of adrenaline and interleukin-1beta on interleukin-6 secretion from cultured murine neurohypophyseal cells. Cells were cultured from neurohypophyses of 3- to 5-week-old mice and experiments were performed after 13 days in culture. Interleukin-6 was measured...... in 24-h samples using a sandwich fluoroimmunoassay. Unstimulated cells released 19+/-3 fmol interleukin-6/neurohypophysis/24 h (mean +/- S.E.M., n = 42). Adrenaline and interleukin-1beta increased the release of interleukin-6 from the cells in a concentration-dependent manner. Incubation with adrenaline...

  20. Biological markers as predictors of radiosensitivity in syngeneic murine tumors

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Sei Kyung; Shin, Hyun Soo [Bundang CHA General Hospital, Seongnam (Korea, Republic of); Seong, Jin Sil; Kim, Sung Hee [Yonsei Cancer Center, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2006-06-15

    We investigated whether a relationship exists between tumor control dose 50 (TCD{sub 50}) or tumor growth delay (TGD) and radiation induced apoptosis (RIA) in syngeneic murine tumors. Also we investigated the biological markers that can predict radiosensitivity in murine tumor system through analysis of relationship between TCD{sub 50}, TGD, RIA and constitutive expression levels of the genetic products regulating RIA. Syngeneic murine tumors such as ovarian adenocarcinoma, mammary carcinoma, squamous cell carcinoma, fibrosarcoma, hepatocarcinoma were used in this study. C3H/HeJ mice were bred and maintained in our specific pathogen free mouse colony and were 8 {approx} 12 weeks old when used for the experiments. The tumors, growing in the right hind legs of mice, were analyzed for TCD{sub 50}, TGD, and RIA at 8 mm in diameter. The tumors were also analyzed for the constitutive expression levels of p53, p21{sup WAF1/CIP1}, BAX, Bcl-2, Bcl-x{sub L}, Bcl-x{sub S}, and p34. Correlation analysis was performed whether the level of RIA were correlated with TCD{sub 50} or TGD, and the constitutive expression levels of genetic products regulating RIA were correlated with TCD{sub 50}, TGD, RIA. The level of RIA showed a significant positive correlation (R = 0.922, {rho} = 0.026) with TGD, and showed a trend to correlation (R = -0.848), marginally significant correlation with TCD{sub 50} ({rho} = 0.070). It indicates that tumors that respond to radiation with high percentage of apoptosis were more radiosensitive. The constitutive expression levels of p21{sup WAF1/CIP1} and p34 showed a significant correlation either with TCD{sub 50} (R = 0.893, {rho} = 0.041 and R = 0.904, {rho} = 0.035) or with TGD (R = -0.922, {rho} 0.026 and R = -0.890, {rho} = 0.043). The tumors with high constitutive expression levels of p21{sup WAF1/CIP1} or p34 were less radiosensitive than those with low expression. Radiosensitivity may be predicted with the level of RIA in murine tumors. The

  1. Determinação das atividades séricas de creatina quinase, lactato desidrogenase e aspartato aminotransferase em eqüinos de diferentes categorias de atividade Determination of serum activities of creatine kinase, lactate dehydrogenase, and aspartate aminotransferase in horses of different activities classes

    Directory of Open Access Journals (Sweden)

    I.A. Câmara e Silva

    2007-02-01

    Full Text Available The creatine kinase (CK, lactate dehydrogenase (LDH, and aspartate aminotransferase (AST seric activities in horses of different activity classes (athlete, traction, and reproduction, were compared. Fifty-eight horses were alloted into three groups - group 1 with 20 athletes, "vaquejada" competitors; group 2 with 20 breeding horses; and group 3 with 18 draft horses, averaging 10 working hours daily. The average values for CK serum activity were 80.2, 83.9, and 94.4 U/l in groups 1, 2, and 3, respectively. Result of group 3 was significantly different from the other groups. The averages values for LDH were 102.5, 98.6, and 112.8 U/l in groups 1, 2, and 3, respectively, with no statistical difference between groups. The AST averages were 56.8, 33.0, and 50.1 U/l in groups 1, 2, and 3, respectively, with group 2 significantly differing from the others. Clinical biochemistry values of muscular function in horses varied according to activity category.

  2. Analysis of the capacity to produce IL-3 in murine AIDS

    DEFF Research Database (Denmark)

    Neuenschwander, A U; Marker, O; Thomsen, Allan Randrup

    1994-01-01

    Adult C57BL/6 mice infected with LP-BM5 murine leukaemia virus represent a model of murine AIDS (MAIDS). In this study we have analysed the capacity of CD4+ T cells from infected mice to produce IL-3 following stimulation with ConA for 24-72 h. In contrast to the position with IL-2, the production...

  3. Murine typhus in two travelers returning from Bali, Indonesia: an underdiagnosed disease.

    Science.gov (United States)

    Takeshita, Nozomi; Imoto, Kazuya; Ando, Shuji; Yanagisawa, Kunio; Ohji, Goh; Kato, Yasuyuki; Sakata, Akiko; Hosokawa, Naoto; Kishimoto, Toshio

    2010-01-01

    Two Japanese travelers from Bali were diagnosed with murine typhus in Japan during the same period. Although one had only mild illness, the other experienced liver and kidney dysfunction. Murine typhus may be missed not only in endemic areas around the world, but also in travelers, especially those returning from marine resorts in these areas. © 2010 International Society of Travel Medicine.

  4. Global Liver Gene Expression Analysis on a Murine Metabolic Syndrome Model Treated by Low-molecular-weight Lychee Fruit Polyphenol (Oligonol®).

    Science.gov (United States)

    Uchiyama, Hironobu; Uehara, Kaori; Nagashima, Takayuki; Nakata, Akifumi; Sato, Keisuke; Mihara, Yoshihiro; Komatsu, Ken-Ich; Takanari, Jun; Shimizu, Shigeomi; Wakame, Koji

    2016-07-01

    Oligonol® (OLG) is a low-molecular-weight lychee fruit polyphenol mainly containing catechin-type monomers and oligomers of proanthocyanidins. Dietary OLG supplementation reportedly improves lipid metabolism disorder and lowers the visceral fat level in animal and human studies. Thus, we investigated the mechanism behind the protective and beneficial effects of OLG on a Western diet (WD)-induced metabolic syndrome (MetS) of a murine model. Using the C57BL/6J mouse for the MetS model, mice were divided into three groups: control (normal diet: ND), Western diet (WD) and WD + 0.5% OLG (OLG) groups. The WD group was fed a high-calorie (high fructose plus high fat) diet for 12 weeks to develop MetS. At week 12, all mice were sacrificed and the blood and liver were obtained for histological and biological examinations and RNA sequencing (RNA-Seq). Body weight, liver weight, plasma triglycerides (TG), total cholesterol (T-Cho) and alanine aminotransferase (ATS) levels of both OLG groups were significantly lower than those of the WD group. On histological examination of the liver, the area of fatty deposits was shown to be suppressed by OLG administration. Expression gene analysis in the liver of WD- versus OLG-fed mice by RNA-Seq showed that 464/45,706 genes exhibited a significant change of expression (corrected p-value metabolism-related genes Lpin1, Adig and Cidea were regulated by OLG administration. OLG may function to suppress MetS and the progression of geriatric diseases in WD-fed mice by regulating the expression of lipid metabolism, inflammation and tumor-related genes in the liver. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  5. β-Arrestin2 mediates progression of murine primary myelofibrosis.

    Science.gov (United States)

    Rein, Lindsay Am; Wisler, James W; Kim, Jihee; Theriot, Barbara; Huang, LiYin; Price, Trevor; Yang, Haeyoon; Chen, Minyong; Chen, Wei; Sipkins, Dorothy; Fedoriw, Yuri; Walker, Julia Kl; Premont, Richard T; Lefkowitz, Robert J

    2017-12-21

    Primary myelofibrosis is a myeloproliferative neoplasm associated with significant morbidity and mortality, for which effective therapies are lacking. β-Arrestins are multifunctional adaptor proteins involved in developmental signaling pathways. One isoform, β-arrestin2 (βarr2), has been implicated in initiation and progression of chronic myeloid leukemia, another myeloproliferative neoplasm closely related to primary myelofibrosis. Accordingly, we investigated the relationship between βarr2 and primary myelofibrosis. In a murine model of MPLW515L-mutant primary myelofibrosis, mice transplanted with donor βarr2-knockout (βarr2-/-) hematopoietic stem cells infected with MPL-mutant retrovirus did not develop myelofibrosis, whereas controls uniformly succumbed to disease. Although transplanted βarr2-/- cells homed properly to marrow, they did not repopulate long-term due to increased apoptosis and decreased self-renewal of βarr2-/- cells. In order to assess the effect of acute loss of βarr2 in established primary myelofibrosis in vivo, we utilized a tamoxifen-induced Cre-conditional βarr2-knockout mouse. Mice that received Cre (+) donor cells and developed myelofibrosis had significantly improved survival compared with controls. These data indicate that lack of antiapoptotic βarr2 mediates marrow failure of murine hematopoietic stem cells overexpressing MPLW515L. They also indicate that βarr2 is necessary for progression of primary myelofibrosis, suggesting that it may serve as a novel therapeutic target in this disease.

  6. Scanning electron microscopy of the neuropathology of murine cerebral malaria

    Directory of Open Access Journals (Sweden)

    Brenneis Christian

    2006-11-01

    Full Text Available Abstract Background The mechanisms leading to death and functional impairments due to cerebral malaria (CM are yet not fully understood. Most of the knowledge about the pathomechanisms of CM originates from studies in animal models. Though extensive histopathological studies of the murine brain during CM are existing, alterations have not been visualized by scanning electron microscopy (SEM so far. The present study investigates the neuropathological features of murine CM by applying SEM. Methods C57BL/6J mice were infected with Plasmodium berghei ANKA blood stages. When typical symptoms of CM developed perfused brains were processed for SEM or light microscopy, respectively. Results Ultrastructural hallmarks were disruption of vessel walls, parenchymal haemorrhage, leukocyte sequestration to the endothelium, and diapedesis of macrophages and lymphocytes into the Virchow-Robin space. Villous appearance of observed lymphocytes were indicative of activated state. Cerebral oedema was evidenced by enlargement of perivascular spaces. Conclusion The results of the present study corroborate the current understanding of CM pathophysiology, further support the prominent role of the local immune system in the neuropathology of CM and might expose new perspectives for further interventional studies.

  7. Targeted destruction of murine macrophage cells with bioconjugated gold nanorods

    Energy Technology Data Exchange (ETDEWEB)

    Pissuwan, Dakrong [University of Technology Sydney, Institute for Nanoscale Technology (Australia); Valenzuela, Stella M. [University of Technology Sydney, Department of Medical and Molecular Biosciences (Australia)], E-mail: stella.valenzuela@uts.edu.au; Killingsworth, Murray C. [Sydney South West Pathology Service (Australia)], E-mail: murray.killingsworth@swsahs.nsw.gov.au; Xu, Xiaoda; Cortie, Michael B. [University of Technology Sydney, Institute for Nanoscale Technology (Australia)], E-mail: michael.cortie@uts.edu.au

    2007-12-15

    Gold nanorods manifest a readily tunable longitudinal plasmon resonance with light and consequently have potential for use in photothermal therapeutics. Recent work by others has shown how gold nanoshells and rods can be used to target cancer cells, which can then be destroyed using relatively high power laser radiation ({approx}1x10{sup 5} to 1x10{sup 10} W/m{sup 2}). Here we extend this concept to demonstrate how gold nanorods can be modified to bind to target macrophage cells, and show that high intensity laser radiation is not necessary, with even 5x10{sup 2} W/m{sup 2} being sufficient, provided that a total fluence of {approx}30 J/cm{sup 2} is delivered. We used the murine cell line RAW 264.7 and the monoclonal antibody CD11b, raised against murine macrophages, as our model system and a 5 mW solid state diode laser as our energy source. Exposure of the cells labeled with gold nanorods to a laser fluence of 30 J/cm{sup 2} resulted in 81% cell death compared to only 0.9% in the control, non-labeled cells.

  8. Targeted destruction of murine macrophage cells with bioconjugated gold nanorods

    Science.gov (United States)

    Pissuwan, Dakrong; Valenzuela, Stella M.; Killingsworth, Murray C.; Xu, Xiaoda; Cortie, Michael B.

    2007-12-01

    Gold nanorods manifest a readily tunable longitudinal plasmon resonance with light and consequently have potential for use in photothermal therapeutics. Recent work by others has shown how gold nanoshells and rods can be used to target cancer cells, which can then be destroyed using relatively high power laser radiation (˜1×105 to 1×1010 W/m2). Here we extend this concept to demonstrate how gold nanorods can be modified to bind to target macrophage cells, and show that high intensity laser radiation is not necessary, with even 5×102 W/m2 being sufficient, provided that a total fluence of ˜30 J/cm2 is delivered. We used the murine cell line RAW 264.7 and the monoclonal antibody CD11b, raised against murine macrophages, as our model system and a 5 mW solid state diode laser as our energy source. Exposure of the cells labeled with gold nanorods to a laser fluence of 30 J/cm2 resulted in 81% cell death compared to only 0.9% in the control, non-labeled cells.

  9. Targeted destruction of murine macrophage cells with bioconjugated gold nanorods

    International Nuclear Information System (INIS)

    Pissuwan, Dakrong; Valenzuela, Stella M.; Killingsworth, Murray C.; Xu, Xiaoda; Cortie, Michael B.

    2007-01-01

    Gold nanorods manifest a readily tunable longitudinal plasmon resonance with light and consequently have potential for use in photothermal therapeutics. Recent work by others has shown how gold nanoshells and rods can be used to target cancer cells, which can then be destroyed using relatively high power laser radiation (∼1x10 5 to 1x10 10 W/m 2 ). Here we extend this concept to demonstrate how gold nanorods can be modified to bind to target macrophage cells, and show that high intensity laser radiation is not necessary, with even 5x10 2 W/m 2 being sufficient, provided that a total fluence of ∼30 J/cm 2 is delivered. We used the murine cell line RAW 264.7 and the monoclonal antibody CD11b, raised against murine macrophages, as our model system and a 5 mW solid state diode laser as our energy source. Exposure of the cells labeled with gold nanorods to a laser fluence of 30 J/cm 2 resulted in 81% cell death compared to only 0.9% in the control, non-labeled cells

  10. Activation of DNA damage repair pathways by murine polyomavirus

    Energy Technology Data Exchange (ETDEWEB)

    Heiser, Katie; Nicholas, Catherine; Garcea, Robert L., E-mail: Robert.Garcea@Colorado.edu

    2016-10-15

    Nuclear replication of DNA viruses activates DNA damage repair (DDR) pathways, which are thought to detect and inhibit viral replication. However, many DNA viruses also depend on these pathways in order to optimally replicate their genomes. We investigated the relationship between murine polyomavirus (MuPyV) and components of DDR signaling pathways including CHK1, CHK2, H2AX, ATR, and DNAPK. We found that recruitment and retention of DDR proteins at viral replication centers was independent of H2AX, as well as the viral small and middle T-antigens. Additionally, infectious virus production required ATR kinase activity, but was independent of CHK1, CHK2, or DNAPK signaling. ATR inhibition did not reduce the total amount of viral DNA accumulated, but affected the amount of virus produced, indicating a defect in virus assembly. These results suggest that MuPyV may utilize a subset of DDR proteins or non-canonical DDR signaling pathways in order to efficiently replicate and assemble. -- Highlights: •Murine polyomavirus activates and recruits DNA damage repair (DDR) proteins to replication centers. •Large T-antigen mediates recruitment of DDR proteins to viral replication centers. •Inhibition or knockout of CHK1, CHK2, DNA-PK or H2AX do not affect viral titers. •Inhibition of ATR activity reduces viral titers, but not viral DNA accumulation.

  11. Application of murine monoclonal antibodies to the serodiagnosis of tuberculosis

    International Nuclear Information System (INIS)

    Ivanyl, J.; Coates, A.R.M.; Krambovitis, E.

    1982-01-01

    The immune response during infectious diseases leads to a rise in antibody titre to the various different antigenic determinants of the causative organism. The response is further complicated by the fact that it is relatively unusual for one individual to respond to all antigenic components of an organism. Demonstration of the specific immune response of an infected host by serological tests is often hampered by the broad cross-reactivity between several bacterial antigens. The authors report on a serodiagnostic application of murine monoclonal antibodies (MAB), specific for a human pathogen, M. tuberculosis by a technique which is applicable in principle to the serodiagnosis of many other infectious diseases. The serum diagnostic test is based on the competitive inhibition by human sera of the binding of 125 I-labelled murine monoclonal antibodies to M. tuberculosis-coated polyvinyl plates. Five monoclonal antibodies binding to distinct antigenic determinants of the organism were used as structural probes which conferred their stringent combining site specificities to the polyclonal mixture of antibodies from patients' sera. When compared with healthy controls, increased titres of inhibitory antibodies were found in about 70% of patients with active tuberculosis. The diagnostic value of the individual monoclonal antibodies as well as the benefit from the use of multiple specificity probes has been qualified

  12. Murine models of osteosarcoma: A piece of the translational puzzle.

    Science.gov (United States)

    Walia, Mannu K; Castillo-Tandazo, Wilson; Mutsaers, Anthony J; Martin, Thomas John; Walkley, Carl R

    2018-06-01

    Osteosarcoma (OS) is the most common cancer of bone in children and young adults. Despite extensive research efforts, there has been no significant improvement in patient outcome for many years. An improved understanding of the biology of this cancer and how genes frequently mutated contribute to OS may help improve outcomes for patients. While our knowledge of the mutational burden of OS is approaching saturation, our understanding of how these mutations contribute to OS initiation and maintenance is less clear. Murine models of OS have now been demonstrated to be highly valid recapitulations of human OS. These models were originally based on the frequent disruption of p53 and Rb in familial OS syndromes, which are also common mutations in sporadic OS. They have been applied to significantly improve our understanding about the functions of recurrently mutated genes in disease. The murine models can be used as a platform for preclinical testing and identifying new therapeutic targets, in addition to testing the role of additional mutations in vivo. Most recently these models have begun to be used for discovery based approaches and screens, which hold significant promise in furthering our understanding of the genetic and therapeutic sensitivities of OS. In this review, we discuss the mouse models of OS that have been reported in the last 3-5 years and newly identified pathways from these studies. Finally, we discuss the preclinical utilization of the mouse models of OS for identifying and validating actionable targets to improve patient outcome. © 2017 Wiley Periodicals, Inc.

  13. Neurological Disorders in a Murine Model of Chronic Renal Failure

    Directory of Open Access Journals (Sweden)

    Jean-Marc Chillon

    2014-01-01

    Full Text Available Cardiovascular disease is highly prevalent in patients with chronic renal failure (CRF. However, data on the impact of CRF on the cerebral circulatory system are scarce—despite the fact that stroke is the third most common cause of cardiovascular death in people with CRF. In the present study, we examined the impact of CRF on behavior (anxiety, recognition and ischemic stroke severity in a well-defined murine model of CRF. We did not observe any significant increases between CRF mice and non-CRF mice in terms of anxiety. In contrast, CRF mice showed lower levels of anxiety in some tests. Recognition was not impaired (vs. controls after 6 weeks of CRF but was impaired after 10 weeks of CRF. Chronic renal failure enhances the severity of ischemic stroke, as evaluated by the infarct volume size in CRF mice after 34 weeks of CRF. Furthermore, neurological test results in non-CRF mice tended to improve in the days following ischemic stroke, whereas the results in CRF mice tended to worsen. In conclusion, we showed that a murine model of CRF is suitable for evaluating uremic toxicity and the associated neurological disorders. Our data confirm the role of uremic toxicity in the genesis of neurological abnormalities (other than anxiety.

  14. Differential chemokine responses in the murine brain following lyssavirus infection.

    Science.gov (United States)

    Hicks, D J; Núñez, A; Banyard, A C; Williams, A; Ortiz-Pelaez, A; Fooks, A R; Johnson, N

    2013-11-01

    The hallmark of lyssavirus infection is lethal encephalomyelitis. Previous studies have reported distinct lyssavirus isolate-related differences in severity of cellular recruitment into the encephalon in a murine model of infection following peripheral inoculation with rabies virus (RABV) and European bat lyssavirus (EBLV)-1 and -2. In order to understand the role of chemokines in this process, comparative studies of the chemokine pattern, distribution and production in response to infection with these lyssaviruses were undertaken. Expression of CCL2, CCL5 and CXCL10 was observed throughout the murine brain with a distinct caudal bias in distribution, similar to both inflammatory changes and virus antigen distribution. CCL2 immunolabelling was localized to neuronal and astroglial populations. CCL5 immunolabelling was only detected in the astroglia, while CXCL10 labelling, although present in the astroglia, was more prominent in neurons. Isolate-dependent differences in the amount of chemokine immunolabelling in specific brain regions and chemokine production by neurons in vitro were observed, with a greater expression of CCL5 in vivo and CXCL10 production in vitro after EBLV infection. Additionally, strong positive associations between chemokine immunolabelling and perivascular cuffing and, to a lesser extent, virus antigen score were also observed. These differences in chemokine expression may explain the variation in severity of encephalitic changes observed in animals infected with different lyssavirus isolates. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  15. Development of a murine model of acute radiation encephalopathy

    International Nuclear Information System (INIS)

    Xing Yigang; Tang Yamei; Liu Jun; Sun Ying

    2003-01-01

    Objective: To develop a murine model of acute radiation encephalopathy. Methods: A total of 40 rats were subjected to local γ-irradiation to the brain with the dosage of 7 Gy/d for 6 consecutive days. The amount of food intake, hairs and skin of irradiated field, body weight, general activities, CNS symptoms and signs were examined and recorded after irradiation. On day 3, 7, 14 and 30, the brain tissue was removed to observe histopathologic changes. Results: During the first two days after irradiation, the irradiated rats were agitated, and the amount of food intake decreased from day 2 onwards. No serious skin reaction to irradiation was observed. Survived rats had normal activities without any abnormal nervous signs. Histopathologic changes showed slight neuronal degeneration, smaller cell body, red-colored cytoplasm, disappearance of Nissl body, vacuolation, typical cell shrinkage, chromatin condensation and nuclear divergence. On the 14th and 30th days, hypochromatism, loose and reticular necrotic foci were found in some samples. Conclusion: The murine model of acute radiation encephalopathy is useful and practical in radiobiological studies

  16. [Nuclear matrix organization of the chromocenters in cultured murine fibroblasts].

    Science.gov (United States)

    Sheval', E V; Poliakov, V Iu

    2010-01-01

    In the current work, the structural organization of nuclear matrix of pericentromeric heterochromatin blocks (chromocenters) inside cultured murine fibroblasts was investigated. After 2 M NaCl extraction without DNase I treatment, chromocenters were extremely swelled, and it was impossible to detect them using conventional electron microscopy. Using immunogolding with anti-topoisomerase IIalpha antibody, we demonstrated that residual chromocenters were subdivided into numerous discrete aggregates. After 2 M NaCl extraction with DNase I treatment, the residual chromocenters appeared as a dense meshwork of thin fibers, and using this feature, the residual chromocenters were easily distinguished from the rest of nuclear matrix. After extraction with dextran sulfate and heparin, the chromocenters were decondensed, and chromatin complexes having rosette organization (central core from which numerous DNA fibers radiated) were seen. Probably, the appearance of these rosettes was a consequence of incomplete chromatin extraction. Thus, the nuclear matrix of pericentromeric chromosome regions in cultured murine fibroblasts differs morphologically from the rest of nuclear matrix.

  17. Effects of the murine skull in optoacoustic brain microscopy.

    Science.gov (United States)

    Kneipp, Moritz; Turner, Jake; Estrada, Héctor; Rebling, Johannes; Shoham, Shy; Razansky, Daniel

    2016-01-01

    Despite the great promise behind the recent introduction of optoacoustic technology into the arsenal of small-animal neuroimaging methods, a variety of acoustic and light-related effects introduced by adult murine skull severely compromise the performance of optoacoustics in transcranial imaging. As a result, high-resolution noninvasive optoacoustic microscopy studies are still limited to a thin layer of pial microvasculature, which can be effectively resolved by tight focusing of the excitation light. We examined a range of distortions introduced by an adult murine skull in transcranial optoacoustic imaging under both acoustically- and optically-determined resolution scenarios. It is shown that strong low-pass filtering characteristics of the skull may significantly deteriorate the achievable spatial resolution in deep brain imaging where no light focusing is possible. While only brain vasculature with a diameter larger than 60 µm was effectively resolved via transcranial measurements with acoustic resolution, significant improvements are seen through cranial windows and thinned skull experiments. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Rediscovering peritoneal macrophages in a murine endometriosis model.

    Science.gov (United States)

    Yuan, Ming; Li, Dong; An, Min; Li, Qiuju; Zhang, Lu; Wang, Guoyun

    2017-01-01

    What are the features of peritoneal macrophage subgroups and T helper cells in the development of murine endometriosis? During the development of endometriosis in a murine model, large peritoneal macrophages (LPMs) and small peritoneal macrophages (SPMs) are polarized into M1 and M2 cells, respectively, and the proportions of T helper (Th) 1, Th17 and T regulatory (T reg ) cells are increased. Numerous studies investigating the etiology and pathogenesis of endometriosis have focused on the polarization states of peritoneal macrophages in endometriosis models and patients, but the results are inconclusive. Further studies indicate that peritoneal macrophages are composed of two distinct subsets: LPMs and SPMs, although their roles in endometriosis are unknown. This study involves a prospective and randomized experiment. Fifty C57BL/6 female mice were randomly allocated to five control and five experimental groups (n = 5/group) according to the presence or absence of transplantation. The transplant periods are 0.25, 3, 14, 28 and 42 days. C57BL/6 mice were utilized to establish an endometriosis model by i.p. injection of allogeneic endometrial segments. Dynamic changes of peritoneal macrophage subsets and polarization profiles were evaluated by flow cytometry (FCM). Macrophage morphology and density were assessed by cell counting under a microscope. Dynamic changes of Th1, Th2, Th17 and T reg cells were estimated by FCM. Peritoneal macrophages are composed of two distinct subsets: LPMs and SPMs. The proportion of SPMs increased immediately after peritoneal injection of endometrial tissues, whereas LPMs showed an opposite trend. Peritoneal macrophages differentiated into both M1 and M2 macrophages. The bidirectional polarization of macrophages was caused by the inverse trends of polarization of LPMs and SPMs. Consistently, the proportions of Th1, Th17 and T reg cells were all increased in mice with endometriosis. N/A. In this study, detection was only performed in a

  19. Nanoliposomal artemisinin for the treatment of murine visceral leishmaniasis

    Directory of Open Access Journals (Sweden)

    Want MY

    2017-03-01

    Full Text Available Muzamil Y Want,1 Mohammad Islammudin,1 Garima Chouhan,1 Hani A Ozbak,2 Hassan A Hemeg,2 Asoke P Chattopadhyay,3 Farhat Afrin2 1Parasite Immunology Laboratory, Department of Biotechnology, Jamia Hamdard, Hamdard University, New Delhi, India; 2Department of Clinical Laboratory Sciences, Faculty of Applied Medical Sciences, Taibah University, Medina, Saudi Arabia; 3Department of Chemistry, University of Kalyani, Kalyani, India Abstract: Visceral leishmaniasis (VL is a fatal, vector-borne disease caused by the intracellular protozoa of the genus Leishmania. Most of the therapeutics for VL are toxic, expensive, or ineffective. Sesquiterpenes are a new class of drugs with proven antimicrobial and antiviral activities. Artemisinin is a sesquiterpene lactone with potent antileishmanial activity, but with limited access to infected cells, being a highly lipophilic molecule. Association of artemisinin with liposome is a desirable strategy to circumvent the problem of poor accessibility, thereby improving its efficacy, as demonstrated in a murine model of experimental VL. Nanoliposomal artemisinin (NLA was prepared by thin-film hydration method and optimized using Box–Behnken design with a mean particle diameter of 83±16 nm, polydispersity index of 0.2±0.03, zeta potential of -27.4±5.7 mV, and drug loading of 33.2%±2.1%. Morphological study of these nanoliposomes by microscopy showed a smooth and spherical surface. The mechanism of release of artemisinin from the liposomes followed the Higuchi model in vitro. NLA was free from concomitant signs of toxicity, both ex vivo in murine macrophages and in vivo in healthy BALB/c mice. NLA significantly denigrated the intracellular infection of Leishmania donovani amastigotes and the number of infected macrophages ex vivo with an IC50 of 6.0±1.4 µg/mL and 5.1±0.9 µg/mL, respectively. Following treatment in a murine model of VL, NLA demonstrated superior efficacy compared to artemisinin with a

  20. Forced recombination of psi-modified murine leukaemia virus-based vectors with murine leukaemia-like and VL30 murine endogenous retroviruses

    DEFF Research Database (Denmark)

    Mikkelsen, J G; Lund, Anders Henrik; Duch, M

    1999-01-01

    Co-encapsidation of retroviral RNAs into virus particles allows for the generation of recombinant proviruses through events of template switching during reverse transcription. By use of a forced recombination system based on recombinational rescue of replication- defective primer binding site-imp....... We note that recombination-based rescue of primer binding site knock-out retroviral vectors may constitute a sensitive assay to register putative genetic interactions involving endogenous retroviral RNAs present in cells of various species.......-impaired Akv-MLV-derived vectors, we here examine putative genetic interactions between vector RNAs and copackaged endogenous retroviral RNAs of the murine leukaemia virus (MLV) and VL30 retroelement families. We show (i) that MLV recombination is not blocked by nonhomology within the 5' untranslated region...... harbouring the supposed RNA dimer-forming cis -elements and (ii) that copackaged retroviral RNAs can recombine despite pronounced sequence dissimilarity at the cross-over site(s) and within parts of the genome involved in RNA dimerization, encapsidation and strand transferring during reverse transcription...

  1. The murine Cd48 gene: allelic polymorphism in the IgV-like region.

    Science.gov (United States)

    Cabrero, J G; Freeman, G J; Reiser, H

    1998-12-01

    The murine CD48 molecule is a member of the immunoglobulin superfamily which regulates the activation of T lymphocytes. prior cloning experiments using mRNA from two different mouse strains had yielded discrepant sequences within the IgV-like domain of murine CD48. To resolve this issue, we have directly sequenced genomic DNA of 10 laboratory strains and two inbred strains of wild origin. The results of our analysis reveal an allelic polymorphism within the IgV-like domain of murine CD48.

  2. Preparation of Murine Submandibular Salivary Gland for Upright Intravital Microscopy.

    Science.gov (United States)

    Ficht, Xenia; Thelen, Flavian; Stolp, Bettina; Stein, Jens V

    2018-05-07

    The submandibular salivary gland (SMG) is one of the three major salivary glands, and is of interest for many different fields of biological research, including cell biology, oncology, dentistry, and immunology. The SMG is an exocrine gland comprised of secretory epithelial cells, myofibroblasts, endothelial cells, nerves, and extracellular matrix. Dynamic cellular processes in the rat and mouse SMG have previously been imaged, mostly using inverted multi-photon microscope systems. Here, we describe a straightforward protocol for the surgical preparation and stabilization of the murine SMG in anesthetized mice for in vivo imaging with upright multi-photon microscope systems. We present representative intravital image sets of endogenous and adoptively transferred fluorescent cells, including the labeling of blood vessels or salivary ducts and second harmonic generation to visualize fibrillar collagen. In sum, our protocol allows for surgical preparation of mouse salivary glands in upright microscopy systems, which are commonly used for intravital imaging in the field of immunology.

  3. Corn silk induces nitric oxide synthase in murine macrophages.

    Science.gov (United States)

    Kim, Kyung A; Choi, Sang Kyu; Choi, Hye Seon

    2004-12-31

    Corn silk has been purified as an anticoagulant previously and the active component is a polysaccharide with a molecular mass of 135 kDa. It activates murine macrophages to induce nitric oxide synthase (NOS) and generate substantial amounts of NO in time and dose-dependent manners. It was detectable first at 15 h after stimulation by corn silk, peaked at 24 h, and undetectable by 48 h. Induction of NOS is inhibited by pyrolidine dithiocarbamate (PDTC) and genistein, an inhibitor of nuclear factor kappa B (NF-kappaB) and tyrosine kinase, respectively, indicating that iNOS stimulated by corn silk is associated with tyrosine kinase and NF-kappaB signaling pathways. IkappaB-alpha degradation was detectible at 10 min, and the level was restored at 120 min after treatment of corn silk. Corn silk induced nuclear translocation of NF-kappaB by phosphorylation and degradation of IkappaB-alpha.

  4. Flow cytometric quantification of radiation responses of murine peritoneal cells

    International Nuclear Information System (INIS)

    Tokita, N.; Raju, M.R.

    1982-01-01

    Methods have been developed to distinguish subpopulations of murine peritoneal cells, and these were applied to the measurement of early changes in peritoneal cells after irradiation. The ratio of the two major subpopulations in the peritoneal fluid, lymphocytes and macrophages, was measured rapidly by means of cell volume distribution analysis as well as by hypotonic propidium iodide (PI) staining. After irradiation, dose and time dependent changes were noted in the cell volume distributions: a rapid loss of peritoneal lymphocytes, and an increase in the mean cell volume of macrophages. The hypotonic PI staining characteristics of the peritoneal cells showed two or three distinctive G 1 peaks. The ratio of the areas of these peaks was also found to be dependent of the radiation dose and the time after irradiation. These results demonstrate that these two parameters may be used to monitor changes induced by irradiation (biological dosimetry), and to sort different peritoneal subpopulations

  5. A novel inexpensive murine model of oral chronic digitalization.

    Science.gov (United States)

    Helber, Izo; Kanashiro, Rosemeire M; Alarcon, Ernesto A; Antonio, Ednei L; Tucci, Paulo J F

    2004-01-01

    A novel inexpensive murine model of oral administration of digitoxin (100 micro g/kg per day) added to routine chow is described. Serum digitoxin levels achieved after oral (n = 5; 116 +/- 14 ng/mL) and subcutaneous (n = 5; 124 +/- 11 ng/mL) administration were similar. A significant increase in the maximal left ventricular pressure rise of treated (n = 9) compared with control (n = 6) rats (dP/dt: 8956 +/- 233 vs 7980 +/- 234 mmHg/s, respectively; P = 0.01) characterized the positive inotropic action of digitoxin. In addition, no differences were observed in treated compared with control rats with regard to the electrocardiogram and systolic and diastolic left ventricular pressures.

  6. The kin17 Protein in Murine Melanoma Cells

    Directory of Open Access Journals (Sweden)

    Anelise C. Ramos

    2015-11-01

    Full Text Available kin17 has been described as a protein involved in the processes of DNA replication initiation, DNA recombination, and DNA repair. kin17 has been studied as a potential molecular marker of breast cancer. This work reports the detection and localization of this protein in the murine melanoma cell line B16F10-Nex2 and in two derived subclones with different metastatic potential, B16-8HR and B16-10CR. Nuclear and chromatin-associated protein fractions were analyzed, and kin17 was detected in all fractions, with an elevated concentration observed in the chromatin-associated fraction of the clone with low metastatic potential, suggesting that the kin17 expression level could be a marker of melanoma.

  7. Haemopedia: An Expression Atlas of Murine Hematopoietic Cells

    Directory of Open Access Journals (Sweden)

    Carolyn A. de Graaf

    2016-09-01

    Full Text Available Hematopoiesis is a multistage process involving the differentiation of stem and progenitor cells into distinct mature cell lineages. Here we present Haemopedia, an atlas of murine gene-expression data containing 54 hematopoietic cell types, covering all the mature lineages in hematopoiesis. We include rare cell populations such as eosinophils, mast cells, basophils, and megakaryocytes, and a broad collection of progenitor and stem cells. We show that lineage branching and maturation during hematopoiesis can be reconstructed using the expression patterns of small sets of genes. We also have identified genes with enriched expression in each of the mature blood cell lineages, many of which show conserved lineage-enriched expression in human hematopoiesis. We have created an online web portal called Haemosphere to make analyses of Haemopedia and other blood cell transcriptional datasets easier. This resource provides simple tools to interrogate gene-expression-based relationships between hematopoietic cell types and genes of interest.

  8. Macropinocytosis is the Entry Mechanism of Amphotropic Murine Leukemia Virus

    DEFF Research Database (Denmark)

    Rasmussen, Izabela; Vilhardt, Frederik

    2015-01-01

    of infection. Understanding how pathogens and toxins exploit or divert endocytosis pathways has advanced our understanding of membrane trafficking pathways, which benefits development of new therapeutical schemes and methods of drug delivery. We show here that Murine Leukemia Virus (A-MLV) pseudotyped......, or NIH-3T3 cells knocked-down for caveolin expression, was unaffected. Conversely, A-MLV infection of NIH-3T3 and HeLa cells was sensitive to amiloride analogues and actin-depolymerizing drugs that interfere with macropinocytosis. Further manipulation of the actin cytoskeleton through conditional...... with the amphotropic (expands the host range to many mammalian cells) envelope protein gains entry into host cells by macropinocytosis. Macropinosomes form as large, fluid-filled vacuoles (up to 10 μm) following collapse of cell surface protrusions and membrane scission. We use drugs or introduction of mutant proteins...

  9. Effects of trichostatins on differentiation of murine erythroleukemia cells

    International Nuclear Information System (INIS)

    Yoshida, M.; Nomura, S.; Beppu, T.

    1987-01-01

    The fungistatic antibiotics trichostatins (TS) A and C were isolated from culture broth of Streptomyces platensis No. 145 and were found to be potent inducers of differentiation in murine erythroleukemia (Friend and RV133) cells at concentrations of 1.5 X 10(-8) M for TSA and 5 X 10(-7) M for TSC. Differentiation induced by TS was cooperatively enhanced by UV irradiation but not by treatment with dimethyl sulfoxide. This enhanced activity was completely inhibited by adding cycloheximide to the culture medium 2 h after exposure to TS, suggesting that TS are dimethyl sulfoxide-type inducers of erythroid differentiation. No inhibitory effect of TS was observed on macromolecular synthesis in cultured cells

  10. First transplantation of isolated murine follicles in alginate.

    Science.gov (United States)

    Vanacker, Julie; Dolmans, Marie-Madeleine; Luyckx, Valérie; Donnez, Jacques; Amorim, Christiani A

    2014-01-01

    Our aim is to develop an artificial ovary allowing survival and growth of isolated follicles and ovarian cells, to restore fertility in women diagnosed with pathologies at high risk of ovarian involvement. For this, alginate beads containing isolated preantral follicles and ovarian cells were autografted to immunocompetent mice. One week after grafting, the beads were invaded by proliferating murine cells (12.1%) and capillaries. The recovery rate of follicles per graft ranged from 0% to 35.5%. Of the analyzed follicles, 77% were Ki67-positive and 81%, TUNEL-negative. Three antral follicles were also identified, evidencing their ability to grow in the matrix. Our results suggest that an artificial ovary is now conceivable, opening new perspectives to restore fertility in women.

  11. Murine model of long-term obstructive jaundice.

    Science.gov (United States)

    Aoki, Hiroaki; Aoki, Masayo; Yang, Jing; Katsuta, Eriko; Mukhopadhyay, Partha; Ramanathan, Rajesh; Woelfel, Ingrid A; Wang, Xuan; Spiegel, Sarah; Zhou, Huiping; Takabe, Kazuaki

    2016-11-01

    With the recent emergence of conjugated bile acids as signaling molecules in cancer, a murine model of obstructive jaundice by cholestasis with long-term survival is in need. Here, we investigated the characteristics of three murine models of obstructive jaundice. C57BL/6J mice were used for total ligation of the common bile duct (tCL), partial common bile duct ligation (pCL), and ligation of left and median hepatic bile duct with gallbladder removal (LMHL) models. Survival was assessed by Kaplan-Meier method. Fibrotic change was determined by Masson-Trichrome staining and Collagen expression. Overall, 70% (7 of 10) of tCL mice died by day 7, whereas majority 67% (10 of 15) of pCL mice survived with loss of jaundice. A total of 19% (3 of 16) of LMHL mice died; however, jaundice continued beyond day 14, with survival of more than a month. Compensatory enlargement of the right lobe was observed in both pCL and LMHL models. The pCL model demonstrated acute inflammation due to obstructive jaundice 3 d after ligation but jaundice rapidly decreased by day 7. The LHML group developed portal hypertension and severe fibrosis by day 14 in addition to prolonged jaundice. The standard tCL model is too unstable with high mortality for long-term studies. pCL may be an appropriate model for acute inflammation with obstructive jaundice, but long-term survivors are no longer jaundiced. The LHML model was identified to be the most feasible model to study the effect of long-term obstructive jaundice. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Gene expression in IFN-g-activated murine macrophages

    Directory of Open Access Journals (Sweden)

    Pereira C.A.

    2004-01-01

    Full Text Available Macrophages are critical for natural immunity and play a central role in specific acquired immunity. The IFN-gamma activation of macrophages derived from A/J or BALB/c mice yielded two different patterns of antiviral state in murine hepatitis virus 3 infection, which were related to a down-regulation of the main virus receptor. Using cDNA hybridization to evaluate mRNA accumulation in the cells, we were able to identify several genes that are differently up- or down-regulated by IFN-gamma in A/J (267 and 266 genes, respectively, up- and down-regulated or BALB/c (297 and 58 genes, respectively, up- and down-regulated mouse macrophages. Macrophages from mice with different genetic backgrounds behave differently at the molecular level and comparison of the patterns of non-activated and IFN-gamma-activated A/J or BALB/c mouse macrophages revealed, for instance, an up-regulation and a down-regulation of genes coding for biological functions such as enzymatic reactions, nucleic acid synthesis and transport, protein synthesis, transport and metabolism, cytoskeleton arrangement and extracellular matrix, phagocytosis, resistance and susceptibility to infection and tumors, inflammation, and cell differentiation or activation. The present data are reported in order to facilitate future correlation of proteomic/transcriptomic findings as well as of results obtained from a classical approach for the understanding of biological phenomena. The possible implication of the role of some of the gene products relevant to macrophage biology can now be further scrutinized. In this respect, a down-regulation of the main murine hepatitis virus 3 receptor gene was detected only in IFN-gamma-activated macrophages of resistant mice.

  13. Alanine-aminotransferase: an early marker for insulin resistance? Alanino-aminotransferasa: ¿un marcador temprano de resistencia a la insulina?

    Directory of Open Access Journals (Sweden)

    Martín R. Salazar

    2007-04-01

    Full Text Available In a population-based sample, after excluding alcohol consumption, hepatotoxic drugs and hepatitis Band C infected, we investigated if alanine-aminotransferase (ALT was associated with metabolic syndrome and insulin resistance, and if this association was caused by non-alcoholic fatty liver disease (NAFLD. The sample (432 female and 119 male was divided into two ALT thresholds corresponding to the 50th and 75th percentiles (P (female ≤ 15 and ≤ 19 U/L; male ≤ 17 and ≤ 23 U/l, respectively. Blood pressure, body mass index, waist circumference, cholesterol, HDL cholesterol (HDLc, triglyceride (TG, TG/HDLc ratio, glycemia and homeostasis model assessment of insulin resistance (HOMA-IR were compared between those above and below each ALT threshold. Female placed above the 50th P of ALT had higher levels of TG/HDLc ratio (p=0.029, glycemia (p=0.028, and homeostasis model assessment of insulin resistance, (p=0.045, and above the 75th P had higher SBP (p=0.036, DBP (p=0.018, TG (p=0.024, TG/HDLc ratio (p=0.028, glycemia (p=0.004 and HOMA-IR (p=0.0014. Male placed above the 50th P of ALT had higher BMI (p=0.017 and TG/HDLc ratio (p=0.048, and above the 75th P had lower values of HDLc (p=0.042. Only 16.5% of women and 14.5% of men, above the 75th P of ALT, showed an increase in liver brightness in the echography. This work shows in woman an early association of ALT with TG/HDLc ratio and HOMA-IR. Since the last two are independent predictors of cardiovascular risk, attention should be drawn to ALT values near the upper limit of the normal range even in the absence of NAFLD and obesity.En una muestra poblacional, luego de excluir a quienes consumían alcohol y drogas hepatotóxicas y a los infectados con virus B y C de la hepatitis, investigamos si la alanino-aminotransferasa (ALT, o transaminasa glutámico pirúvica (TGP, se asociaba con el síndrome metabólico y con resistencia a la insulina y si esta asociación se explicaba por enfermedad hep

  14. Chimeric anti-tenascin antibody 81C6: Increased tumor localization compared with its murine parent

    International Nuclear Information System (INIS)

    Zalutsky, Michael R.; Archer, Gary E.; Garg, Pradeep K.; Batra, Surinder K.; Bigner, Darell D.

    1996-01-01

    When labeled using the Iodogen method, a chimeric antibody composed of the human IgG 2 constant region and the variable regions of murine anti-tenascin 81C6 exhibited superior uptake in human glioma xenografts compared with its murine parent. In the current study, three paired-label experiments were performed in athymic mice with subcutaneous D-54 MG human glioma xenografts to evaluate further the properties of radioiodinated chimeric 81C6. These studies demonstrated that (a) the enhanced tumor uptake of chimeric 81C6 is specific; (b) when labeling was performed using N-succinimidyl 3-iodobenzoate, chimeric 81C6 again showed preferential accumulation in tumor compared with murine 81C6; and (c) the tumor uptake advantage observed previously with murine 81C6 for N-succinimidyl 3-iodobenzoate compared with Iodogen labeling did not occur with chimeric 81C6

  15. Responses of the Murine Myeloid Colony-Forming Cell to Ansamycin Antibiotics

    Science.gov (United States)

    Horoszewicz, Julius S.; Carter, William A.

    1974-01-01

    The in vitro susceptibility of murine myeloid colony-forming cells to the antiproliferative activities of three ansamycin antibiotics was determined. These cells were found to be 10- to 40-fold more susceptible than the corresponding human ones. PMID:4151701

  16. Diagnosing hypoxia in murine models of rheumatoid arthritis from reflectance multispectral images

    Science.gov (United States)

    Glinton, Sophie; Naylor, Amy J.; Claridge, Ela

    2017-07-01

    Spectra computed from multispectral images of murine models of Rheumatoid Arthritis show a characteristic decrease in reflectance within the 600-800nm region which is indicative of the reduction in blood oxygenation and is consistent with hypoxia.

  17. Acute Febrile Illness and Complications Due to Murine Typhus, Texas, USA1,2.

    Science.gov (United States)

    Afzal, Zeeshan; Kallumadanda, Sunand; Wang, Feng; Hemmige, Vagish; Musher, Daniel

    2017-08-01

    Murine typhus occurs relatively commonly in southern Texas, as well as in California. We reviewed records of 90 adults and children in whom murine typhus was diagnosed during a 3-year period in 2 hospitals in southern Texas, USA. Most patients lacked notable comorbidities; all were immunocompetent. Initial signs and symptoms included fever (99%), malaise (82%), headache (77%), fatigue (70%), myalgias (68%), and rash (39%). Complications, often severe, in 28% of patients included bronchiolitis, pneumonia, meningitis, septic shock, cholecystitis, pancreatitis, myositis, and rhabdomyolysis; the last 3 are previously unreported in murine typhus. Low serum albumin and elevated procalcitonin, consistent with bacterial sepsis, were observed in >70% of cases. Rash was more common in children; thrombocytopenia, hyponatremia, elevated hepatic transaminases, and complications were more frequent in adults. Murine typhus should be considered as a diagnostic possibility in cases of acute febrile illness in southern and even in more northern US states.

  18. A fluorescence model of the murine lung for optical detection of pathogenic bacteria

    Science.gov (United States)

    Durkee, Madeleine S.; Cirillo, Jeffrey D.; Maitland, Kristen C.

    2017-07-01

    We present a computer model of intravital excitation and external fluorescence detection in the murine lungs validated with a three-dimensional lung tissue phantom. The model is applied to optical detection of pulmonary tuberculosis infection.

  19. Radiobiological studies on target cell populations in murine bone marrow transplantation recipients.

    NARCIS (Netherlands)

    van Os, Ronald Peter

    1994-01-01

    The experiments presented in this thesis were designed to investigate the role of total body irradiation (TBI) in conditioning murine recipients of syngeneic and allogeneic bone marrow transplantation (BMT). ... Zie: Summary

  20. Acute lethal toxicity following passive immunization for treatment of murine cryptococcosis.

    OpenAIRE

    Savoy, A C; Lupan, D M; Manalo, P B; Roberts, J S; Schlageter, A M; Weinhold, L C; Kozel, T R

    1997-01-01

    Passive immunization with monoclonal antibodies (MAbs) specific for the major capsular polysaccharide of Cryptococcus neoformans alters the course of murine cryptococcosis. During studies of passive immunization for treatment of murine cryptococcosis, we noted the occurrence of an acute, lethal toxicity. Toxicity was characterized by scratching, lethargy, respiratory distress, collapse, and death within 20 to 60 min after injection of antibody. The toxic effect was observed only in mice with ...

  1. Behavior of a cloned murine interferon alpha/beta receptor expressed in homospecific or heterospecific background.

    Science.gov (United States)

    Uzé, G; Lutfalla, G; Bandu, M T; Proudhon, D; Mogensen, K E

    1992-05-15

    A murine interferon (IFN) alpha/beta receptor was cloned from the IFN-sensitive L1210 cell line on the basis of its homology with the human receptor. A combination of methods that includes the screening of random-primed and oligo(dT)-primed cDNA libraries and polymerase chain reactions with a single-side specificity was used. At the amino acid level, the murine IFN-alpha/beta shows 46% identity with its human counterpart. Both human WISH cells presenting a low sensitivity to mouse IFN and a murine L1210 mutant subline that does not express the receptor have been stably transfected with the murine IFN-alpha/beta receptor. Whereas transfected human cells became sensitive to a limited number of mouse IFN-alpha/beta subtypes, the transfected murine L1210 mutant was found to be fully complemented and became sensitive to all mouse IFN-alpha/beta subtypes tested, including those that were not active on transfected human cells. These results strongly suggest that the receptor described here is implicated in the mediation of the activities of all murine IFN-alpha/beta subtypes.

  2. A role for smoothened during murine lens and cornea development.

    Directory of Open Access Journals (Sweden)

    Janet J Y Choi

    Full Text Available Various studies suggest that Hedgehog (Hh signalling plays roles in human and zebrafish ocular development. Recent studies (Kerr et al., Invest Ophthalmol Vis Sci. 2012; 53, 3316-30 showed that conditionally activating Hh signals promotes murine lens epithelial cell proliferation and disrupts fibre differentiation. In this study we examined the expression of the Hh pathway and the requirement for the Smoothened gene in murine lens development. Expression of Hh pathway components in developing lens was examined by RT-PCR, immunofluorescence and in situ hybridisation. The requirement of Smo in lens development was determined by conditional loss-of-function mutations, using LeCre and MLR10 Cre transgenic mice. The phenotype of mutant mice was examined by immunofluorescence for various markers of cell cycle, lens and cornea differentiation. Hh pathway components (Ptch1, Smo, Gli2, Gli3 were detected in lens epithelium from E12.5. Gli2 was particularly localised to mitotic nuclei and, at E13.5, Gli3 exhibited a shift from cytosol to nucleus, suggesting distinct roles for these transcription factors. Conditional deletion of Smo, from ∼E12.5 (MLR10 Cre did not affect ocular development, whereas deletion from ∼E9.5 (LeCre resulted in lens and corneal defects from E14.5. Mutant lenses were smaller and showed normal expression of p57Kip2, c-Maf, E-cadherin and Pax6, reduced expression of FoxE3 and Ptch1 and decreased nuclear Hes1. There was normal G1-S phase but decreased G2-M phase transition at E16.5 and epithelial cell death from E14.5-E16.5. Mutant corneas were thicker due to aberrant migration of Nrp2+ cells from the extraocular mesenchyme, resulting in delayed corneal endothelial but normal epithelial differentiation. These results indicate the Hh pathway is required during a discrete period (E9.5-E12.5 in lens development to regulate lens epithelial cell proliferation, survival and FoxE3 expression. Defective corneal development occurs

  3. Handling stress may confound murine gut microbiota studies

    Directory of Open Access Journals (Sweden)

    Cary R. Allen-Blevins

    2017-01-01

    Full Text Available Background Accumulating evidence indicates interactions between human milk composition, particularly sugars (human milk oligosaccharides or HMO, the gut microbiota of human infants, and behavioral effects. Some HMO secreted in human milk are unable to be endogenously digested by the human infant but are able to be metabolized by certain species of gut microbiota, including Bifidobacterium longum subsp. infantis (B. infantis, a species sensitive to host stress (Bailey & Coe, 2004. Exposure to gut bacteria like B. infantisduring critical neurodevelopment windows in early life appears to have behavioral consequences; however, environmental, physical, and social stress during this period can also have behavioral and microbial consequences. While rodent models are a useful method for determining causal relationships between HMO, gut microbiota, and behavior, murine studies of gut microbiota usually employ oral gavage, a technique stressful to the mouse. Our aim was to develop a less-invasive technique for HMO administration to remove the potential confound of gavage stress. Under the hypothesis that stress affects gut microbiota, particularly B. infantis, we predicted the pups receiving a prebiotic solution in a less-invasive manner would have the highest amount of Bifidobacteria in their gut. Methods This study was designed to test two methods, active and passive, of solution administration to mice and the effects on their gut microbiome. Neonatal C57BL/6J mice housed in a specific-pathogen free facility received increasing doses of fructooligosaccharide (FOS solution or deionized, distilled water. Gastrointestinal (GI tracts were collected from five dams, six sires, and 41 pups over four time points. Seven fecal pellets from unhandled pups and two pellets from unhandled dams were also collected. Qualitative real-time polymerase chain reaction (qRT-PCR was used to quantify and compare the amount of Bifidobacterium, Bacteroides, Bacteroidetes, and

  4. Assessment of carbon nanoparticle exposure on murine macrophage function

    Science.gov (United States)

    Suro-Maldonado, Raquel M.

    There is growing concern about the potential cytotoxicity of nanoparticles. Exposure to respirable ultrafine particles (2.5uM) can adversely affect human health and have been implicated with episodes of increased respiratory diseases such as asthma and allergies. Nanoparticles are of particular interest because of their ability to penetrate into the lung and potentially elicit health effects triggering immune responses. Nanoparticles are structures and devises with length scales in the 1 to 100-nanometer range. Black carbon (BC) nanoparticles have been observed to be products of combustion, especially flame combustion and multi-walled carbon nanotubes (MWCNT) have been shown to be found in both indoor and outdoor air. Furthermore, asbestos, which have been known to cause mesothelioma as well as lung cancer, have been shown to be structurally identical to MWCNTs. The aims of these studies were to examine the effects of carbon nanoparticles on murine macrophage function and clearance mechanisms. Macrophages are immune cells that function as the first line of defense against invading pathogens and are likely to be amongst the first cells affected by nanoparticles. Our research focused on two manufactured nanoparticles, MWCNT and BC. The two were tested against murine-derived macrophages in a chronic contact model. We hypothesized that long-term chronic exposure to carbon nanoparticles would decrease macrophages ability to effectively respond to immunological challenge. Production of nitric oxide (NO), tumor necrosis factor alpha (TNF-alpha), cell surface macrophage; activation markers, reactive oxygen species formation (ROS), and antigen processing and presentation were examined in response to lipopolysaccharide (LPS) following a 144hr exposure to the particulates. Data demonstrated an increase in TNF-alpha, and NO production; a decrease in phagocytosis and antigen processing and presentation; and a decrease in the expression levels of cell surface macrophage

  5. Expression, purification, crystallization, data collection and preliminary biochemical characterization of methicillin-resistant Staphylococcus aureus Sar2028, an aspartate/tyrosine/phenylalanine pyridoxal-5′-phosphate-dependent aminotransferase

    International Nuclear Information System (INIS)

    Seetharamappa, Jaldappagari; Oke, Muse; Liu, Huanting; McMahon, Stephen A.; Johnson, Kenneth A.; Carter, Lester; Dorward, Mark; Zawadzki, Michal; Overton, Ian M.; Niekirk, C. A. Johannes van; Graham, Shirley; Botting, Catherine H.; Taylor, Garry L.; White, Malcolm F.; Barton, Geoffrey J.; Coote, Peter J.; Naismith, James H.

    2007-01-01

    As part of work on S. aureus, the crystallization of Sar2028, a protein that is upregulated in MRSA, is reported. Sar2028, an aspartate/tyrosine/phenylalanine pyridoxal-5′-phosphate-dependent aminotransferase with a molecular weight of 48 168 Da, was overexpressed in methicillin-resistant Staphylococcus aureus compared with a methicillin-sensitive strain. The protein was expressed in Escherichia coli, purified and crystallized. The protein crystallized in a primitive orthorhombic Laue group with unit-cell parameters a = 83.6, b = 91.3, c = 106.0 Å, α = β = γ = 90°. Analysis of the systematic absences along the three principal axes indicated the space group to be P2 1 2 1 2 1 . A complete data set was collected to 2.5 Å resolution

  6. DMPD: Toll-like receptor 9 in murine lupus: more friend than foe! [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 18241699 Toll-like receptor 9 in murine lupus: more friend than foe! Yu P, Musette ...us: more friend than foe! PubmedID 18241699 Title Toll-like receptor 9 in murine lupus...P, Peng SL. Immunobiology. 2008;213(2):151-7. Epub 2007 Sep 21. (.png) (.svg) (.html) (.csml) Show Toll-like receptor 9 in murine lup

  7. Murine Models of Heart Failure With Preserved Ejection Fraction

    Directory of Open Access Journals (Sweden)

    Maria Valero-Muñoz, PhD

    2017-12-01

    Full Text Available Heart failure with preserved ejection fraction (HFpEF is characterized by signs and symptoms of heart failure in the presence of a normal left ventricular ejection fraction. Despite accounting for up to 50% of all clinical presentations of heart failure, the mechanisms implicated in HFpEF are poorly understood, thus precluding effective therapy. The pathophysiological heterogeneity in the HFpEF phenotype also contributes to this disease and likely to the absence of evidence-based therapies. Limited access to human samples and imperfect animal models that completely recapitulate the human HFpEF phenotype have impeded our understanding of the mechanistic underpinnings that exist in this disease. Aging and comorbidities such as atrial fibrillation, hypertension, diabetes and obesity, pulmonary hypertension, and renal dysfunction are highly associated with HFpEF, yet the relationship and contribution between them remains ill-defined. This review discusses some of the distinctive clinical features of HFpEF in association with these comorbidities and highlights the advantages and disadvantage of commonly used murine models used to study the HFpEF phenotype.

  8. Murine colon proteome and characterization of the protein pathways

    Directory of Open Access Journals (Sweden)

    Magdeldin Sameh

    2012-08-01

    Full Text Available Abstract Background Most of the current proteomic researches focus on proteome alteration due to pathological disorders (i.e.: colorectal cancer rather than normal healthy state when mentioning colon. As a result, there are lacks of information regarding normal whole tissue- colon proteome. Results We report here a detailed murine (mouse whole tissue- colon protein reference dataset composed of 1237 confident protein (FDR I and Mw ranged from 3–12 and 4–600 KDa, respectively. Gravy index scoring predicted 19.5% membranous and 80.5% globularly located proteins. GO hierarchies and functional network analysis illustrated proteins function together with their relevance and implication of several candidates in malignancy such as Mitogen- activated protein kinase (Mapk8, 9 in colorectal cancer, Fibroblast growth factor receptor (Fgfr 2, Glutathione S-transferase (Gstp1 in prostate cancer, and Cell division control protein (Cdc42, Ras-related protein (Rac1,2 in pancreatic cancer. Protein abundances calculated with 3 different algorithms (NSAF, PAF and emPAI provide a relative quantification under normal condition as guidance. Conclusions This highly confidence colon proteome catalogue will not only serve as a useful reference for further experiments characterizing differentially expressed proteins induced from diseased conditions, but also will aid in better understanding the ontology and functional absorptive mechanism of the colon as well.

  9. A murine model of targeted infusion for intracranial tumors.

    Science.gov (United States)

    Kim, Minhyung; Barone, Tara A; Fedtsova, Natalia; Gleiberman, Anatoli; Wilfong, Chandler D; Alosi, Julie A; Plunkett, Robert J; Gudkov, Andrei; Skitzki, Joseph J

    2016-01-01

    Historically, intra-arterial (IA) drug administration for malignant brain tumors including glioblastoma multiforme (GBM) was performed as an attempt to improve drug delivery. With the advent of percutaneous neuorovascular techniques and modern microcatheters, intracranial drug delivery is readily feasible; however, the question remains whether IA administration is safe and more effective compared to other delivery modalities such as intravenous (IV) or oral administrations. Preclinical large animal models allow for comparisons between treatment routes and to test novel agents, but can be expensive and difficult to generate large numbers and rapid results. Accordingly, we developed a murine model of IA drug delivery for GBM that is reproducible with clear readouts of tumor response and neurotoxicities. Herein, we describe a novel mouse model of IA drug delivery accessing the internal carotid artery to treat ipsilateral implanted GBM tumors that is consistent and reproducible with minimal experience. The intent of establishing this unique platform is to efficiently interrogate targeted anti-tumor agents that may be designed to take advantage of a directed, regional therapy approach for brain tumors.

  10. Antinociception induced by rosuvastatin in murine neuropathic pain.

    Science.gov (United States)

    Miranda, Hugo F; Sierralta, Fernando; Aranda, Nicolas; Poblete, Paula; Castillo, Rodrigo L; Noriega, Viviana; Prieto, Juan Carlos

    2018-06-01

    Neuropathic pain, and subsequent hypernociception, can be induced in mice by paclitaxel (PTX) administration and partial sciatic nerve ligation (PSNL). Its pharmacotherapy has been a clinical challenge, due to a lack of effective treatment. In two models of mouse neuropathic pain (PTX and PSNL) the antinociception induced by rosuvastatin and the participation of proinflammatory biomarkers, interleukin (IL)- 1β, TBARS and glutathione were evaluated. A dose-response curve for rosuvastatin ip was obtained on cold plate, hot plate and Von Frey assays. Changes on spinal cord levels of IL-1β, glutathione and lipid peroxidation were measured at 7 and 14days in PTX and PSNL murine models. PTX or PSNL were able to induce in mice peripheral neuropathy with hypernociception, either to 7 and 14days. Rosuvastatin induced a dose dependent antinociception in hot plate, cold plate and Von Frey assays. The increased levels of IL-1β or TBARS induced by pretreatment with PTX or PSNL were reduced by rosuvastatin. The reduction of spinal cord glutathione, by PTX or PSNL, expressed as the ratio GSH/GSSG, were increased significantly in animals pretreated with rosuvastatin. The anti-inflammatory properties of statins could underlie their beneficial effects on neuropathic pain by reduction of proinflammatory biomarkers and activation of glia. The findings of this study suggest a potential usefulness of rosuvastatin in the treatment of neuropathic pain. Copyright © 2018 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  11. Murine leukemia virus (MLV replication monitored with fluorescent proteins

    Directory of Open Access Journals (Sweden)

    Bittner Alexandra

    2004-12-01

    Full Text Available Abstract Background Cancer gene therapy will benefit from vectors that are able to replicate in tumor tissue and cause a bystander effect. Replication-competent murine leukemia virus (MLV has been described to have potential as cancer therapeutics, however, MLV infection does not cause a cytopathic effect in the infected cell and viral replication can only be studied by immunostaining or measurement of reverse transcriptase activity. Results We inserted the coding sequences for green fluorescent protein (GFP into the proline-rich region (PRR of the ecotropic envelope protein (Env and were able to fluorescently label MLV. This allowed us to directly monitor viral replication and attachment to target cells by flow cytometry. We used this method to study viral replication of recombinant MLVs and split viral genomes, which were generated by replacement of the MLV env gene with the red fluorescent protein (RFP and separately cloning GFP-Env into a retroviral vector. Co-transfection of both plasmids into target cells resulted in the generation of semi-replicative vectors, and the two color labeling allowed to determine the distribution of the individual genomes in the target cells and was indicative for the occurrence of recombination events. Conclusions Fluorescently labeled MLVs are excellent tools for the study of factors that influence viral replication and can be used to optimize MLV-based replication-competent viruses or vectors for gene therapy.

  12. Collagen-Induced Arthritis: A model for Murine Autoimmune Arthritis.

    Science.gov (United States)

    Pietrosimone, K M; Jin, M; Poston, B; Liu, P

    2015-10-20

    Collagen-induced arthritis (CIA) is a common autoimmune animal model used to study rheumatoid arthritis (RA). The development of CIA involves infiltration of macrophages and neutrophils into the joint, as well as T and B cell responses to type II collagen. In murine CIA, genetically susceptible mice (DBA/1J) are immunized with a type II bovine collagen emulsion in complete Freund's adjuvant (CFA), and receive a boost of type II bovine collagen in incomplete Freund's adjuvant (IFA) 21 days after the first injection. These mice typically develop disease 26 to 35 days after the initial injection. C57BL/6J mice are resistant to arthritis induced by type II bovine collagen, but can develop arthritis when immunized with type II chicken collagen in CFA, and receive a boost of type II chicken collagen in IFA 21 days after the first injection. The concentration of heat-killed Mycobacterium tuberculosis H37RA (MT) in CFA also differs for each strain. DBA/1J mice develop arthritis with 1 mg/ml MT, while C57BL/6J mice require and 3-4 mg/ml MT in order to develop arthritis. CIA develops slowly in C57BL/6J mice and cases of arthritis are mild when compared to DBA/1J mice. This protocol describes immunization of DBA/1J mice with type II bovine collagen and the immunization of C57BL/6J mice with type II chicken collagen.

  13. An in vitro model of murine middle ear epithelium.

    Science.gov (United States)

    Mulay, Apoorva; Akram, Khondoker M; Williams, Debbie; Armes, Hannah; Russell, Catherine; Hood, Derek; Armstrong, Stuart; Stewart, James P; Brown, Steve D M; Bingle, Lynne; Bingle, Colin D

    2016-11-01

    Otitis media (OM), or middle ear inflammation, is the most common paediatric disease and leads to significant morbidity. Although understanding of underlying disease mechanisms is hampered by complex pathophysiology it is clear that epithelial abnormalities underpin the disease. There is currently a lack of a well-characterised in vitro model of the middle ear (ME) epithelium that replicates the complex cellular composition of the middle ear. Here, we report the development of a novel in vitro model of mouse middle ear epithelial cells (mMECs) at an air-liquid interface (ALI) that recapitulates the characteristics of the native murine ME epithelium. We demonstrate that mMECs undergo differentiation into the varied cell populations seen within the native middle ear. Proteomic analysis confirmed that the cultures secrete a multitude of innate defence proteins from their apical surface. We showed that the mMECs supported the growth of the otopathogen, nontypeable Haemophilus influenzae (NTHi), suggesting that the model can be successfully utilised to study host-pathogen interactions in the middle ear. Overall, our mMEC culture system can help to better understand the cell biology of the middle ear and improve our understanding of the pathophysiology of OM. The model also has the potential to serve as a platform for validation of treatments designed to reverse aspects of epithelial remodelling that underpin OM development. © 2016. Published by The Company of Biologists Ltd.

  14. Hamster and Murine Models of Severe Destructive Lyme Arthritis

    Science.gov (United States)

    Munson, Erik; Nardelli, Dean T.; Du Chateau, Brian K.; Callister, Steven M.; Schell, Ronald F.

    2012-01-01

    Arthritis is a frequent complication of infection in humans with Borrelia burgdorferi. Weeks to months following the onset of Lyme borreliosis, a histopathological reaction characteristic of synovitis including bone, joint, muscle, or tendon pain may occur. A subpopulation of patients may progress to a chronic, debilitating arthritis months to years after infection which has been classified as severe destructive Lyme arthritis. This arthritis involves focal bone erosion and destruction of articular cartilage. Hamsters and mice are animal models that have been utilized to study articular manifestations of Lyme borreliosis. Infection of immunocompetent LSH hamsters or C3H mice results in a transient synovitis. However, severe destructive Lyme arthritis can be induced by infecting irradiated hamsters or mice and immunocompetent Borrelia-vaccinated hamsters, mice, and interferon-gamma- (IFN-γ-) deficient mice with viable B. burgdorferi. The hamster model of severe destructive Lyme arthritis facilitates easy assessment of Lyme borreliosis vaccine preparations for deleterious effects while murine models of severe destructive Lyme arthritis allow for investigation of mechanisms of immunopathology. PMID:22461836

  15. Mechanism of immunotoxicological effects of tributyltin chloride on murine thymocytes.

    Science.gov (United States)

    Sharma, Neelima; Kumar, Anoop

    2014-04-01

    Tributyltin-chloride, a well-known organotin compound, is a widespread environmental toxicant. The immunotoxic effects of tributyltin-chloride on mammalian system and its mechanism is still unclear. This study is designed to explore the mode of action of tributyltin-induced apoptosis and other parallel apoptotic pathways in murine thymocytes. The earliest response in oxidative stress followed by mitochondrial membrane depolarization and caspase-3 activation has been observed. Pre-treatment with N-acetyl cysteine and buthionine sulfoximine effectively inhibited the tributyltin-induced apoptotic DNA and elevated the sub G1 population, respectively. Caspase inhibitors pretreatment prevent tributyltin-induced apoptosis. Western blot and flow cytometry indicate no translocation of apoptosis-inducing factor and endonuclease G in the nuclear fraction from mitochondria. Intracellular Ca(2+) levels are significantly raised by tributyltin chloride. These results clearly demonstrate caspase-dependent apoptotic pathway and support the role of oxidative stress, mitochondrial membrane depolarization, caspase-3 activation, and calcium during tributyltin-chloride (TBTC)-induced thymic apoptosis.

  16. Genomic rearrangement in radiation-induced murine myeloid leukemia

    International Nuclear Information System (INIS)

    Ishihara, Hiroshi

    1994-01-01

    After whole body irradiation of 3Gy X ray to C3H/He male mice, acute myeloid leukemia is induced at an incidence of 20 to 30% within 2 years. We have studied the mechanism of occurrence of this radiation-induced murine myeloid leukemia. Detection and isolation of genomic structural aberration which may be accumulated accompanied with leukemogenesis are helpful in analyzing the complicated molecular process from radiation damage to leukemogenesis. So, our research work was done in three phases. First, structures of previously characterized oncogenes and cytokine-related genes were analyzed, and abnormal structures of fms(protooncogene encoding M-CSF receptor gene)-related and myc-related genes were found in several leukemia cells. Additionally, genomic structural aberration of IL-3 gene was observed in some leukemia cells, so that construction of genomic libraries and cloning of the abnormal IL-3 genomic DNAs were performed to characterize the structure. Secondly, because the breakage of chromosome 2 that is frequently observed in myeloid leukemia locates in proximal position of IL-1 gene cluster in some cases, the copy number of IL-1 gene was determined and the gene was cloned. Lastly, the abnormal genome of leukemia cell was cloned by in-gel competence reassociation method. We discussed these findings and evaluated the analysis of the molecular process of leukemogenesis using these cloned genomic fragments. (author)

  17. Effect of SPG (Sonifilan) immunotherapy and PDT on murine tumor

    International Nuclear Information System (INIS)

    Korbelik, M.; Krosl, G.; Dougherty, G.J.; Chaplin, D.J.

    1992-01-01

    PhotoDynamic Therapy of solid tumors is unique in eliciting a strong host immune response unparalleled in other cancer therapies. This immune response is manifested as an acute inflammatory reaction, and can be readily seen as redness and edema around the treated area. Destruction of typical solid tumor cannot be accomplished solely by direct phototoxic action. This was shown to be the case even with drugs more potent in this direct killing effect than Photofrin, the photosensitizer presently used in clinical PDT. Limiting factors seem to be regional insufficiencies in supply of molecular oxygen, needed for generation of phototoxic species. They can be ascribed to the existence of chronically and acute hypoxic tumor regions, oxygen consumption by the photodynamic process, and vascular shutdown induced during PDT. The remaining tumor mass is eradicated by an indirect effect, necrosis induced by destruction of tumor vasculature. Since most events in PDT treated tumor that lead to vascular collapse are, in fact, typical inflammatory manifestations, it was suggested that PDT-induced acute inflammatory reaction actually leads to vascular damage. In a related report characteristics are shown of cellular inflammatory infiltrate in PDT-treated murine tumor. This work examines the effect of combining PDT with immunotherapy, in an attempt to investigate a possibility of amplification of immune reaction to PDT and its direction towards more pervasive destruction of treated tumors. (authors). 6 refs

  18. Reduction in DNA repair capacity following differentiation of murine proadipocytes

    International Nuclear Information System (INIS)

    Tofilon, P.J.; Meyn, R.E.

    1988-01-01

    It has been suggested that terminally differentiated mammalian cells have a decreased DNA repair capacity, compared with proliferating stem cells. To investigate this hypothesis, we have examined γ-ray-induced DNA strand breaks and their repair in the murine proadipocyte stem cell line 3T3-T. By exposure to human plasma, 3T3-T cells can be induced to undergo nonterminal and then terminal differentiation. DNA strand breaks were evaluated using the technique of alkaline elution. No difference was detected among stem, nonterminally differentiated, and terminally differentiated cells in the initial levels of radiation-induced DNA strand breaks. Each of the strand break dose responses increased as a linear function of γ-ray dose. The strand breaks induced by 4 Gy rejoined following biphasic kinetics for each cell type. At each time point examined after irradiation, however, the percentage of strand breaks that had not rejoined in terminally differentiated cells was three to six times greater than in stem cells. The rate of strand break rejoining in nonterminally differentiated cells was of an intermediate value between that of the stem and of the terminally differentiated cells. These results indicate that, at least for 3T3-T cells, differentiated cells have a reduced capacity for DNA repair

  19. Enterocin CRL35 inhibits Listeria monocytogenes in a murine model.

    Science.gov (United States)

    Salvucci, Emiliano; Saavedra, Lucila; Hebert, Elvira Maria; Haro, Cecilia; Sesma, Fernando

    2012-01-01

    Listeria monocytogenes is a foodborne pathogen causative of opportunistic infections. Listeriosis is associated with severe infections in pregnant women causing abortion or neonatal listeriosis. An alternative to antibiotics are safe novel bacteriocins peptides such as enterocin CRL35 with strong antilisterial activity produced by Enterococcus mundtii CRL35. In the present paper, our goal is to study the effectiveness of this peptide and the producer strain in a murine model of pregnancy-associated listeriosis. A single dose of 5×10(9) colony-forming unit of L. monocytogenes FBUNT (Faculty of Biochemistry-University of Tucumán) resulted in translocation of pathogen to liver and spleen of BALB/c pregnant mice. The maximum level of Listeria was observed on day 3 postinfection. Interestingly, the intragastric administration of enterocin CRL35 significantly reduced the translocation of the pathogen to vital organs. On the other hand, the preadministration of E. mundtii CRL35 slightly inhibited this translocation. Listeria infection caused a significant increase in polymorphonuclear leukocytes at day 3 postinfection compared to the noninfected group. This value was reduced after the administration of enterocin CRL35. No significant changes were observed in either white blood cells or lymphocytes counts. Based on the data presented in the present work enterocin CRL35 would be a promising alternative for the prevention of Listeria infections.

  20. Effects of spaceflight on the muscles of the murine shoulder.

    Science.gov (United States)

    Shen, Hua; Lim, Chanteak; Schwartz, Andrea G; Andreev-Andrievskiy, Alexander; Deymier, Alix C; Thomopoulos, Stavros

    2017-12-01

    Mechanical loading is necessary for the development and maintenance of the musculoskeletal system. Removal of loading via microgravity, paralysis, or bed rest leads to rapid loss of muscle mass and function; however, the molecular mechanisms that lead to these changes are largely unknown, particularly for the spaceflight (SF) microgravity environment. Furthermore, few studies have explored these effects on the shoulder, a dynamically stabilized joint with a large range of motion; therefore, we examined the effects of microgravity on mouse shoulder muscles for the 15-d Space Transportation System (STS)-131, 13-d STS-135, and 30-d Bion-M1 missions. Mice from STS missions were euthanized within 4 h after landing, whereas mice from the Bion-M1 mission were euthanized within 14 h after landing. The motion-generating deltoid muscle was more sensitive to microgravity than the joint-stabilizing rotator cuff muscles. Mice from the STS-131 mission exhibited reduced myogenic ( Myf5 and -6 ) and adipogenic ( Pparg , Cebpa , and Lep ) gene expression, whereas either no change or an increased expression of these genes was observed in mice from the Bion-M1 mission. In summary, muscle responses to microgravity were muscle-type specific, short-duration SF caused dramatic molecular changes to shoulder muscles and responses to reloading upon landing were rapid.-Shen, H., Lim, C., Schwartz, A. G., Andreev-Andrievskiy, A., Deymier, A. C., Thomopoulos, S. Effects of spaceflight on the muscles of the murine shoulder. © FASEB.

  1. Megakaryocytes compensate for Kit insufficiency in murine arthritis.

    Science.gov (United States)

    Cunin, Pierre; Penke, Loka R; Thon, Jonathan N; Monach, Paul A; Jones, Tatiana; Chang, Margaret H; Chen, Mary M; Melki, Imene; Lacroix, Steve; Iwakura, Yoichiro; Ware, Jerry; Gurish, Michael F; Italiano, Joseph E; Boilard, Eric; Nigrovic, Peter A

    2017-05-01

    The growth factor receptor Kit is involved in hematopoietic and nonhematopoietic development. Mice bearing Kit defects lack mast cells; however, strains bearing different Kit alleles exhibit diverse phenotypes. Herein, we investigated factors underlying differential sensitivity to IgG-mediated arthritis in 2 mast cell-deficient murine lines: KitWsh/Wsh, which develops robust arthritis, and KitW/Wv, which does not. Reciprocal bone marrow transplantation between KitW/Wv and KitWsh/Wsh mice revealed that arthritis resistance reflects a hematopoietic defect in addition to mast cell deficiency. In KitW/Wv mice, restoration of susceptibility to IgG-mediated arthritis was neutrophil independent but required IL-1 and the platelet/megakaryocyte markers NF-E2 and glycoprotein VI. In KitW/Wv mice, platelets were present in numbers similar to those in WT animals and functionally intact, and transfer of WT platelets did not restore arthritis susceptibility. These data implicated a platelet-independent role for the megakaryocyte, a Kit-dependent lineage that is selectively deficient in KitW/Wv mice. Megakaryocytes secreted IL-1 directly and as a component of circulating microparticles, which activated synovial fibroblasts in an IL-1-dependent manner. Transfer of WT but not IL-1-deficient megakaryocytes restored arthritis susceptibility to KitW/Wv mice. These findings identify functional redundancy among Kit-dependent hematopoietic lineages and establish an unanticipated capacity of megakaryocytes to mediate IL-1-driven systemic inflammatory disease.

  2. Chromosomal mechanisms in murine radiation acute myeloid leukemogenesis

    International Nuclear Information System (INIS)

    Bouffler, S.D.; Breckon, G.; Cox, R.

    1996-01-01

    Chromosome 2 abnormalities, particularly interstitial deletions, characterize murine radiation-induced acute myeloid leukaemias (AMLs). Here, G-band analyses in CBA/H mice of early (1-6 month) post 3 Gy X-radiation events in bone marrow cells in vivo and karyotype evolution in one unusual AML are presented. The early event analysis showed that all irradiated animals carry chromosome 2 abnormalities, that chromosome 2 abnormalities are more frequent than expected and that interstitial deletions are more common in chromosome 2 than in the remainder of the genome. On presentation AML case N122 carried a t(2; 11) terminal translocation which, with passaging, evolved into a del2(C3F3). Therefore two pathways in leukaemogenesis might exist, one deletion-driven, the other terminal tranlocation-driven involving interstitial genes and terminal genes respectively of chromosome 2. As all irradiated individuals carried chromosome 2 abnormalities, the formation of these aberrations does not determine individual leukaemogenic sensitivity as only 20-25% of animals would be expected to develop AML. Similar lines of argument suggest that chromosome 2 abnormalities are necessary but not sufficient for radiation leukaemogenesis in CBA/H nor are they rate limiting in leukaemogenesis. (Author)

  3. Retino-hypothalamic regulation of light-induced murine sleep

    Directory of Open Access Journals (Sweden)

    Fanuel eMuindi

    2014-08-01

    Full Text Available The temporal organization of sleep is regulated by an interaction between the circadian clock and homeostatic processes. Light indirectly modulates sleep through its ability to phase shift and entrain the circadian clock. Light can also exert a direct, circadian-independent effect on sleep. For example, acute exposure to light promotes sleep in nocturnal animals and wake in diurnal animals. The mechanisms whereby light directly influences sleep and arousal are not well understood. In this review, we discuss the direct effect of light on sleep at the level of the retina and hypothalamus in rodents. We review murine data from recent publications showing the roles of rod-, cone- and melanopsin-based photoreception on the initiation and maintenance of light-induced sleep. We also present hypotheses about hypothalamic mechanisms that have been advanced to explain the acute control of sleep by light. Specifically, we review recent studies assessing the roles of the ventrolateral preoptic area and the suprachiasmatic nucleus. We also discuss how light might differentially promote sleep and arousal in nocturnal and diurnal animals respectively. Lastly, we suggest new avenues for research on this topic which is still in its early stages.

  4. Tofacitinib Ameliorates Murine Lupus and Its Associated Vascular Dysfunction.

    Science.gov (United States)

    Furumoto, Yasuko; Smith, Carolyne K; Blanco, Luz; Zhao, Wenpu; Brooks, Stephen R; Thacker, Seth G; Abdalrahman, Zarzour; Sciumè, Giuseppe; Tsai, Wanxia L; Trier, Anna M; Nunez, Leti; Mast, Laurel; Hoffmann, Victoria; Remaley, Alan T; O'Shea, John J; Kaplan, Mariana J; Gadina, Massimo

    2017-01-01

    Dysregulation of innate and adaptive immune responses contributes to the pathogenesis of systemic lupus erythematosus (SLE) and its associated premature vascular damage. No drug to date targets both systemic inflammatory disease and the cardiovascular complications of SLE. Tofacitinib is a JAK inhibitor that blocks signaling downstream of multiple cytokines implicated in lupus pathogenesis. While clinical trials have shown that tofacitinib exhibits significant clinical efficacy in various autoimmune diseases, its role in SLE and the associated vascular pathology remains to be characterized. MRL/lpr lupus-prone mice were administered tofacitinib or vehicle by gavage for 6 weeks (therapeutic arm) or 8 weeks (preventive arm). Nephritis, skin inflammation, serum levels of autoantibodies and cytokines, mononuclear cell phenotype and gene expression, neutrophil extracellular traps (NETs) release, endothelium-dependent vasorelaxation, and endothelial differentiation were compared in treated and untreated mice. Treatment with tofacitinib led to significant improvement in measures of disease activity, including nephritis, skin inflammation, and autoantibody production. In addition, tofacitinib treatment reduced serum levels of proinflammatory cytokines and interferon responses in splenocytes and kidney tissue. Tofacitinib also modulated the formation of NETs and significantly increased endothelium-dependent vasorelaxation and endothelial differentiation. The drug was effective in both preventive and therapeutic strategies. Tofacitinib modulates the innate and adaptive immune responses, ameliorates murine lupus, and improves vascular function. These results indicate that JAK inhibitors have the potential to be beneficial in SLE and its associated vascular damage. © 2016, American College of Rheumatology.

  5. Combination effect of cisplatin and radiation in murine solid tumors

    International Nuclear Information System (INIS)

    Egawa, Shin; Lee, Kan-ei; Ishibashi, Akira; Komiyama, Hiroki; Umezawa, Iwao.

    1986-01-01

    The combination effect of cisplatin and radiation was studied using the two different murine systems of sarcoma 180 and Ehrlich solid tumors. In sarcoma 180 solid tumor the minimal effective doses (MED) of cisplatin and radiation were 19.5 mg/kg and 10375 rad respectively whereas these doses did not show any effective antitumor activity practically. Administration of cisplatin with a doses of 9 mg/kg given 24 hours before radiation (1000 rad), however, showed synergistic antitumor activity. In Ehrlich solid tumor the MED of cisplatin and radiation were 13.8 mg/kg and 2892 rad respectively. Treatment with cisplatin, 3, 6 or 9 mg/kg, given 24 hours before radiation (1000 rad) showed also synergistic antitumor activity also. Sodium thiosulfate (STS) rescue was effective in reducing toxicity of cisplatin on combined use of the drug with radiation. Cell kinetics of sarcoma 180 solid tumor in vivo after the combined treatment was analyzed by computer aided flowcytometry. Accumulation of cells in the radiosensitive G 2 + M phase was observed 18 to 42 hours after a single intraperitoneal administration of 9 mg/kg of cisplatin. It is strongly suggested that this synchronization is one of the mechanisms of the synergism in the combination therapy. (author)

  6. High salt intake does not exacerbate murine autoimmune thyroiditis

    Science.gov (United States)

    Kolypetri, P; Randell, E; Van Vliet, B N; Carayanniotis, G

    2014-01-01

    Recent studies have shown that high salt (HS) intake exacerbates experimental autoimmune encephalomyelitis and have raised the possibility that a HS diet may comprise a risk factor for autoimmune diseases in general. In this report, we have examined whether a HS diet regimen could exacerbate murine autoimmune thyroiditis, including spontaneous autoimmune thyroiditis (SAT) in non-obese diabetic (NOD.H2h4) mice, experimental autoimmune thyroiditis (EAT) in C57BL/6J mice challenged with thyroglobulin (Tg) and EAT in CBA/J mice challenged with the Tg peptide (2549–2560). The physiological impact of HS intake was confirmed by enhanced water consumption and suppressed aldosterone levels in all strains. However, the HS treatment failed to significantly affect the incidence and severity of SAT or EAT or Tg-specific immunoglobulin (Ig)G levels, relative to control mice maintained on a normal salt diet. In three experimental models, these data demonstrate that HS intake does not exacerbate autoimmune thyroiditis, indicating that a HS diet is not a risk factor for all autoimmune diseases. PMID:24528002

  7. An in vitro model of murine middle ear epithelium

    Directory of Open Access Journals (Sweden)

    Apoorva Mulay

    2016-11-01

    Full Text Available Otitis media (OM, or middle ear inflammation, is the most common paediatric disease and leads to significant morbidity. Although understanding of underlying disease mechanisms is hampered by complex pathophysiology it is clear that epithelial abnormalities underpin the disease. There is currently a lack of a well-characterised in vitro model of the middle ear (ME epithelium that replicates the complex cellular composition of the middle ear. Here, we report the development of a novel in vitro model of mouse middle ear epithelial cells (mMECs at an air–liquid interface (ALI that recapitulates the characteristics of the native murine ME epithelium. We demonstrate that mMECs undergo differentiation into the varied cell populations seen within the native middle ear. Proteomic analysis confirmed that the cultures secrete a multitude of innate defence proteins from their apical surface. We showed that the mMECs supported the growth of the otopathogen, nontypeable Haemophilus influenzae (NTHi, suggesting that the model can be successfully utilised to study host–pathogen interactions in the middle ear. Overall, our mMEC culture system can help to better understand the cell biology of the middle ear and improve our understanding of the pathophysiology of OM. The model also has the potential to serve as a platform for validation of treatments designed to reverse aspects of epithelial remodelling that underpin OM development.

  8. Snake venoms components with antitumor activity in murine melanoma cells

    International Nuclear Information System (INIS)

    Queiroz, Rodrigo Guimaraes

    2012-01-01

    Despite the constant advances in the treatment of cancer, this disease remains one of the main causes of mortality worldwide. So, the development of new treatment modalities is imperative. Snake venom causes a variety of biological effects because they constitute a complex mixture of substances as disintegrins, proteases (serine and metalo), phospholipases A2, L-amino acid oxidases and others. The goal of the present work is to evaluate a anti-tumor activity of some snake venoms fractions. There are several studies of components derived from snake venoms with this kind of activity. After fractionation of snake venoms of the families Viperidae and Elapidae, the fractions were assayed towards murine melanoma cell line B16-F10 and fibroblasts L929. The results showed that the fractions of venom of the snake Notechis ater niger had higher specificity and potential antitumor activity on B16-F10 cell line than the other studied venoms. Since the components of this venom are not explored yet coupled with the potential activity showed in this work, we decided to choose this venom to develop further studies. The cytotoxic fractions were evaluated to identify and characterize the components that showed antitumoral activity. Western blot assays and zymography suggests that these proteins do not belong to the class of metallo and serine proteinases. (author)

  9. Electrocautery effect on intestinal vascularisation in a murine model.

    Science.gov (United States)

    Tremblay, Jean-François; Sideris, Lucas; Leblond, François A; Trépanier, Jean-Sébastien; Badrudin, David; Drolet, Pierre; Mitchell, Andrew; Dubé, Pierre

    2016-09-01

    The use of electrocautery devices is associated with complications such as perforation or fistulisation when used near intestinal structures. This is likely due to its effect on vascularisation of the bowel wall. To test this hypothesis we established a murine model to quantify the effect of electrocautery injury on the intestinal microvascularisation. Sprague-Dawley rats were subjected to five electrocautery injuries on the small bowel in coagulation mode (30 W intensity) and in cut mode (40 W, 80 W and 200 W intensities) for durations of 1, 2 and 5 s. 5 mg/kg of fluorescein was injected intravenously, the injured bowel segments harvested and the rat sacrificed. The segments were analysed to measure the fluorescence of injured bowel compared to adjacent unharmed tissue. A significant decrease in bowel wall microvascularisation occurred with increasing intensity (coag 30 W/cut 40 W versus cut 200 W 1 s: p electrocautery injury (cut 40 W 1/2 s versus 5 s: p electrocautery injury, a significantly greater microvascularisation decrease was observed in jejunum compared to ileum (p electrocautery use. Unsurprisingly, the decrease in microvascularisation is greater with higher intensity and duration of electrocautery and is associated with more perforations in the experimental model. The jejunum seems more vulnerable to electrocautery injury than the ileum. These observations support caution when using electrocautery devices near intestinal structures.

  10. Melatonin modulates adiponectin expression on murine colitis with sleep deprivation.

    Science.gov (United States)

    Kim, Tae Kyun; Park, Young Sook; Baik, Haing-Woon; Jun, Jin Hyun; Kim, Eun Kyung; Sull, Jae Woong; Sung, Ho Joong; Choi, Jin Woo; Chung, Sook Hee; Gye, Myung Chan; Lim, Ju Yeon; Kim, Jun Bong; Kim, Seong Hwan

    2016-09-07

    To determine adiponectin expression in colonic tissue of murine colitis and systemic cytokine expression after melatonin treatments and sleep deprivation. The following five groups of C57BL/6 mice were used in this study: (1) group I, control; (2) group II, 2% DSS induced colitis for 7 d; (3) group III, 2% DSS induced colitis and melatonin treatment; (4) group IV, 2% DSS induced colitis with sleep deprivation (SD) using specially designed and modified multiple platform water baths; and (5) group V, 2% DSS induced colitis with SD and melatonin treatment. Melatonin (10 mg/kg) or saline was intraperitoneally injected daily to mice for 4 d. The body weight was monitored daily. The degree of colitis was evaluated histologically after sacrificing the mice. Immunohistochemical staining and Western blot analysis was performed using anti-adiponectin antibody. After sampling by intracardiac punctures, levels of serum cytokines were measured by ELISA. Sleep deprivation in water bath exacerbated DSS induced colitis and worsened weight loss. Melatonin injection not only alleviated the severity of mucosal injury, but also helped survival during stressful condition. The expression level of adiponectin in mucosa was decreased in colitis, with the lowest level observed in colitis combined with sleep deprivation. Melatonin injection significantly (P sleep deprivation.

  11. Concepts for treatment of micrometastases developed in murine systems

    International Nuclear Information System (INIS)

    Schabel, F.M. Jr.

    1976-01-01

    Current knowledge of tumor cell population growth kinetics indicates that the growth fraction (viable tumor cells undergoing active cell replication) is inversely related to population size. Tumor cells in micrometastases should, therefore, be more sensitive to anticancer drugs active against anabolizing cells than are tumor cells in the larger, grossly apparent primary tumor from which they were derived. This indicates the probability that micrometastases will be effectively responsive to more drugs than is the primary and clinically apparent tumor from which they came. Studies with at least four metastatic and uniformly fatal murine solid tumors (lung, breast, colon, and melanoma) have demonstrated significantly improved cure rates with drug treatment following surgical removal of the grossly apparent primary tumor than can be obtained with either surgery or drug treatment when used alone. Further, both disease staging and drug dosage have been shown to influence cure rates of combined-modality treatment. With several mouse tumors, a significantly smaller number of viable tumor cells can establish lethal tumors in the presence of radiation-inactivated tumor cells than in their absence. This suggests that small numbers of residual viable tumor cells in radiation-treated tumor sites may be a greater threat to clinical cure than smaller tumor cell populations remaining in situ after surgery

  12. Serial passaging of Candida albicans in systemic murine infection suggests that the wild type strain SC5314 is well adapted to the murine kidney.

    Directory of Open Access Journals (Sweden)

    Anja Lüttich

    Full Text Available The opportunistic fungal pathogen Candida albicans has a remarkable ability to adapt to unfavorable environments by different mechanisms, including microevolution. For example, a previous study has shown that passaging through the murine spleen can cause new phenotypic characteristics. Since the murine kidney is the main target organ in murine Candida sepsis and infection of the spleen differs from the kidney in several aspects, we tested whether C. albicans SC5314 could evolve to further adapt to infection and persistence within the kidney. Therefore, we performed a long-term serial passage experiment through the murine kidney of using a low infectious dose. We found that the overall virulence of the commonly used wild type strain SC5314 did not change after eight passages and that the isolated pools showed only very moderate changes of phenotypic traits on the population level. Nevertheless, the last passage showed a higher phenotypic variability and a few individual strains exhibited phenotypic alterations suggesting that microevolution has occurred. However, the majority of the tested single strains were phenotypically indistinguishable from SC5314. Thus, our findings indicate that characteristics of SC5314 which are important to establish and maintain kidney infection over a prolonged time are already well developed.

  13. Differential activation of murine herpesvirus 68- and Kaposi's sarcoma-associated herpesvirus-encoded ORF74 G protein-coupled receptors by human and murine chemokines

    NARCIS (Netherlands)

    Verzijl, D.; Fitzsimons, C.P.; Van Dijk, M.; Stewart, J.P.; Timmerman, H.; Smit, M.J.; Leurs, R.

    2004-01-01

    Infection of mice with murine gammaherpesvirus 68 (MHV-68) is a well-characterized small animal model for the study of gammaherpesvirus infection. MHV-68 belongs to the same herpesvirus family as herpesvirus saimiri (HVS) of New World squirrel monkeys and human herpesvirus 8 (HHV-8) (also referred

  14. Chest radiographic findings of tsutsugamushi disease and murine typhus in Chunchon

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Heung Chul; Han, Tae Giun; Jang, Won Ho; Hwang, Woo Chul; Park, Man Soo; Lee, Myoung Gu; Kim, Yoon Won [School of Medicine, Hallym University, Chuncheon (Korea, Republic of); Park, Choong Ki [College of Medicine, Hanyang University, Guri (Korea, Republic