101
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Is Ro 61-8048 a potential fast-acting antidepressant? J Neurol Sci 2012; 315:180; author reply 181-2. [DOI: 10.1016/j.jns.2011.11.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Revised: 10/18/2011] [Accepted: 11/29/2011] [Indexed: 11/18/2022]
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102
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Stone TW, Forrest CM, Darlington LG. Kynurenine pathway inhibition as a therapeutic strategy for neuroprotection. FEBS J 2012; 279:1386-97. [DOI: 10.1111/j.1742-4658.2012.08487.x] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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103
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Zunszain PA, Anacker C, Cattaneo A, Choudhury S, Musaelyan K, Myint AM, Thuret S, Price J, Pariante CM. Interleukin-1β: a new regulator of the kynurenine pathway affecting human hippocampal neurogenesis. Neuropsychopharmacology 2012; 37:939-49. [PMID: 22071871 PMCID: PMC3280640 DOI: 10.1038/npp.2011.277] [Citation(s) in RCA: 279] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
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.
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Affiliation(s)
- Patricia A Zunszain
- Section of Perinatal Psychiatry and Stress, Psychiatry and Immunology (SPI-lab), Department of Psychological Medicine, Institute of Psychiatry, King's College London, London, UK
| | - Christoph Anacker
- Section of Perinatal Psychiatry and Stress, Psychiatry and Immunology (SPI-lab), Department of Psychological Medicine, Institute of Psychiatry, King's College London, London, UK
| | - Annamaria Cattaneo
- Biology and Genetic Division, Department of Biomedical Sciences and Biotechnology, University of Brescia, Brescia, Italy
| | - Shanas Choudhury
- Section of Perinatal Psychiatry and Stress, Psychiatry and Immunology (SPI-lab), Department of Psychological Medicine, Institute of Psychiatry, King's College London, London, UK
| | - Ksenia Musaelyan
- Section of Perinatal Psychiatry and Stress, Psychiatry and Immunology (SPI-lab), Department of Psychological Medicine, Institute of Psychiatry, King's College London, London, UK
| | - Aye Mu Myint
- Psychiatric Hospital, Ludwig-Maximilian University, Munich, Germany
| | - Sandrine Thuret
- Centre for the Cellular Basis of Behaviour (CCBB), Institute of Psychiatry, King's College London, London, UK
| | - Jack Price
- Centre for the Cellular Basis of Behaviour (CCBB), Institute of Psychiatry, King's College London, London, UK
| | - Carmine M Pariante
- Section of Perinatal Psychiatry and Stress, Psychiatry and Immunology (SPI-lab), Department of Psychological Medicine, Institute of Psychiatry, King's College London, London, UK,Section of Perinatal Psychiatry and Stress, Psychiatry and Immunology (SPI-lab), Department of Psychological Medicine, Reader in Biological Psychiatry and Head of the Sections of Perinatal Psychiatry & Stress, Institute of Psychiatry, King's College London, The James Black Centre, 125 Coldharbour Lane, London SE5 9NU, UK, Tel: +44 (0) 20 7848 0807, Fax: +44 (0) 20 7848 0986, E-mail:
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104
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Szabó N, Kincses ZT, Toldi J, Vécsei L. Altered tryptophan metabolism in Parkinson's disease: A possible novel therapeutic approach. J Neurol Sci 2011; 310:256-60. [DOI: 10.1016/j.jns.2011.07.021] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2011] [Revised: 07/13/2011] [Accepted: 07/14/2011] [Indexed: 02/06/2023]
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105
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Sathyasaikumar KV, Stachowski EK, Wonodi I, Roberts RC, Rassoulpour A, McMahon RP, Schwarcz R. Impaired kynurenine pathway metabolism in the prefrontal cortex of individuals with schizophrenia. Schizophr Bull 2011; 37:1147-56. [PMID: 21036897 PMCID: PMC3196941 DOI: 10.1093/schbul/sbq112] [Citation(s) in RCA: 183] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
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.
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Affiliation(s)
- Korrapati V. Sathyasaikumar
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore
| | - Erin K. Stachowski
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore
| | - Ikwunga Wonodi
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore
| | - Rosalinda C. Roberts
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore,Present address: Department of Psychiatry and Behavioral Neurobiology, University of Alabama, Birmingham, AL 35294
| | - Arash Rassoulpour
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore
| | - Robert P. McMahon
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore
| | - Robert Schwarcz
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore,To whom correspondence should be addressed; Maryland Psychiatric Research Center, PO Box 21247, Baltimore, MD 21228; tel: 410-402-7635, fax: 410-747-2434, e-mail:
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106
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Campesan S, Green EW, Breda C, Sathyasaikumar KV, Muchowski PJ, Schwarcz R, Kyriacou CP, Giorgini F. The kynurenine pathway modulates neurodegeneration in a Drosophila model of Huntington's disease. Curr Biol 2011; 21:961-6. [PMID: 21636279 DOI: 10.1016/j.cub.2011.04.028] [Citation(s) in RCA: 189] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 04/18/2011] [Accepted: 04/18/2011] [Indexed: 11/26/2022]
Abstract
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.
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Affiliation(s)
- Susanna Campesan
- Department of Genetics, University of Leicester, Leicester LE1 7RH, UK
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107
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Wonodi I, Stine OC, Sathyasaikumar KV, Roberts RC, Mitchell BD, Hong LE, Kajii Y, Thaker GK, Schwarcz R. Downregulated kynurenine 3-monooxygenase gene expression and enzyme activity in schizophrenia and genetic association with schizophrenia endophenotypes. ACTA ACUST UNITED AC 2011; 68:665-74. [PMID: 21727251 DOI: 10.1001/archgenpsychiatry.2011.71] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CONTEXT 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. OBJECTIVES 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. DESIGN Case-control postmortem and clinical study. SETTING Maryland Brain Collection, outpatient clinics. PARTICIPANTS 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). MAIN OUTCOME MEASURES 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). RESULTS 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. CONCLUSION Our results provide converging lines of evidence implicating reduced KMO activity in the etiopathophysiology of schizophrenia and related neurocognitive deficits.
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Affiliation(s)
- Ikwunga Wonodi
- Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD 21228.
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108
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Abstract
Abnormalities in the kynurenine pathway are associated with neurodegenerative disorders. Zwilling et al. (2011) show that inhibition of kynurenine 3-monooxygenase in the body's periphery leads to an increase in kyneuric acid, a neuroprotective compound, in the brain. This intervention ameliorates neurodegeneration in mouse models of Alzheimer's disease and Huntington's disease.
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Affiliation(s)
- Peter H Reinhart
- Proteostasis Therapeutics, Inc., 200 Technology Square, Suite 402, Cambridge, MA 02139, USA
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109
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Zwilling D, Huang SY, Sathyasaikumar KV, Notarangelo FM, Guidetti P, Wu HQ, Lee J, Truong J, Andrews-Zwilling Y, Hsieh EW, Louie JY, Wu T, Scearce-Levie K, Patrick C, Adame A, Giorgini F, Moussaoui S, Laue G, Rassoulpour A, Flik G, Huang Y, Muchowski JM, Masliah E, Schwarcz R, Muchowski PJ. Kynurenine 3-monooxygenase inhibition in blood ameliorates neurodegeneration. Cell 2011; 145:863-74. [PMID: 21640374 DOI: 10.1016/j.cell.2011.05.020] [Citation(s) in RCA: 314] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2011] [Revised: 04/30/2011] [Accepted: 05/12/2011] [Indexed: 10/18/2022]
Abstract
Metabolites in the kynurenine pathway, generated by tryptophan degradation, are thought to play an important role in neurodegenerative disorders, including Alzheimer's and Huntington's diseases. In these disorders, glutamate receptor-mediated excitotoxicity and free radical formation have been correlated with decreased levels of the neuroprotective metabolite kynurenic acid. Here, we describe the synthesis and characterization of JM6, a small-molecule prodrug inhibitor of kynurenine 3-monooxygenase (KMO). Chronic oral administration of JM6 inhibits KMO in the blood, increasing kynurenic acid levels and reducing extracellular glutamate in the brain. In a transgenic mouse model of Alzheimer's disease, JM6 prevents spatial memory deficits, anxiety-related behavior, and synaptic loss. JM6 also extends life span, prevents synaptic loss, and decreases microglial activation in a mouse model of Huntington's disease. These findings support a critical link between tryptophan metabolism in the blood and neurodegeneration, and they provide a foundation for treatment of neurodegenerative diseases.
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Affiliation(s)
- Daniel Zwilling
- Gladstone Institute of Neurological Disease, University of California, San Francisco, San Francisco, CA 94158, USA
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110
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Stone TW, Forrest CM, Stoy N, Darlington LG. Involvement of kynurenines in Huntington's disease and stroke-induced brain damage. J Neural Transm (Vienna) 2011; 119:261-74. [PMID: 21695417 DOI: 10.1007/s00702-011-0676-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Accepted: 06/08/2011] [Indexed: 01/13/2023]
Abstract
Several components of the kynurenine pathway of tryptophan metabolism are now recognised to have actions of profound biological importance. These include the ability to modulate the activation of glutamate and nicotinic receptors, to modify the responsiveness of the immune system to inflammation and infection, and to modify the generation and removal of reactive oxygen species. As each of these factors is being recognised increasingly as contributing to major disorders of the central nervous system (CNS), so the potentially fundamental role of the kynurenine pathway in those disorders is presenting a valuable target both for understanding the progress of those disorders and for developing potential drug treatments. This review will summarise some of the evidence for an important contribution of the kynurenines to Huntington's disease and to stroke damage in the CNS. Together with preliminary evidence from a study of kynurenine metabolites after major surgery, an important conclusion is that kynurenine pathway activation closely reflects cognitive function, and may play a significant role in cognitive ability.
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Affiliation(s)
- Trevor W Stone
- Institute of Neuroscience and Psychology, West Medical Building, University of Glasgow, Glasgow, G12 8QQ, UK.
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111
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Inhibition of the kynurenine-NAD+ pathway leads to energy failure and exacerbates apoptosis in pneumococcal meningitis. J Neuropathol Exp Neurol 2010; 69:1096-104. [PMID: 20940631 DOI: 10.1097/nen.0b013e3181f7e7e9] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Pneumococcal meningitis causes neurological sequelae, including learning and memory deficits in up to half of the survivors. In both humans and in animal models of the disease, there is apoptotic cell death in the hippocampus, a brain region involved in learning and memory function. We previously demonstrated that in an infant rat model of pneumococcal meningitis, there is activation of the kynurenine (KYN) pathway in the hippocampus, and that there was a positive correlation between the concentration of 3-hydroxykynurenine and the extent of hippocampal apoptosis. To clarify the role of the KYN pathway in the pathogenesis of hippocampal apoptosis in pneumococcal meningitis, we specifically inhibited 2 key enzymes of the KYN pathway and assessed hippocampal apoptosis, KYN pathway metabolites, and nicotinamide adenine dinucleotide (NAD) concentrations by high-performance liquid chromatography. Pharmacological inhibition of kynurenine 3-hydroxylase and kynureninase led to decreased cellular NAD levels and increased apoptosis in the hippocampus. The cerebrospinal fluid levels of tumor necrosis factor and interleukin-1α and -β were not affected. Our data suggest that activation of the KYN pathway in pneumococcal meningitis is neuroprotective by compensating for an increased NAD demand caused by infection and inflammation;this mechanism may prevent energy failure and apoptosis in the hippocampus.
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112
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Rossi F, Valentina C, Garavaglia S, Sathyasaikumar KV, Schwarcz R, Kojima SI, Okuwaki K, Ono SI, Kajii Y, Rizzi M. Crystal structure-based selective targeting of the pyridoxal 5'-phosphate dependent enzyme kynurenine aminotransferase II for cognitive enhancement. J Med Chem 2010; 53:5684-9. [PMID: 20684605 DOI: 10.1021/jm100464k] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Fluctuations in the brain levels of the neuromodulator kynurenic acid may control cognitive processes and play a causative role in several catastrophic brain diseases. Elimination of the pyridoxal 5'-phosphate dependent enzyme kynurenine aminotransferase II reduces cerebral kynurenic acid synthesis and has procognitive effects. The present description of the crystal structure of human kynurenine aminotransferase II in complex with its potent and specific primary amine-bearing fluoroquinolone inhibitor (S)-(-)-9-(4-aminopiperazin-1-yl)-8-fluoro-3-methyl-6-oxo-2,3-dihydro-6H-1-oxa-3a-azaphenalene-5-carboxylic acid (BFF-122) should facilitate the structure-based development of cognition-enhancing drugs. From a medicinal chemistry perspective our results demonstrate that the issue of inhibitor specificity for highly conserved PLP-dependent enzymes could be successfully addressed.
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Affiliation(s)
- Franca Rossi
- University of Piemonte Orientale Amedeo Avogadro, Novara, Italy
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113
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Pittelli M, Formentini L, Faraco G, Lapucci A, Rapizzi E, Cialdai F, Romano G, Moneti G, Moroni F, Chiarugi A. Inhibition of nicotinamide phosphoribosyltransferase: cellular bioenergetics reveals a mitochondrial insensitive NAD pool. J Biol Chem 2010; 285:34106-14. [PMID: 20724478 DOI: 10.1074/jbc.m110.136739] [Citation(s) in RCA: 147] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The NAD rescue pathway consists of two enzymatic steps operated by nicotinamide phosphoribosyltransferase (Nampt) and nicotinamide mononucleotide adenylyltransferases. Recently, the potent Nampt inhibitor FK866 has been identified and evaluated in clinical trials against cancer. Yet, how Nampt inhibition affects NAD contents and bioenergetics is in part obscure. It is also unknown whether NAD rescue takes place in mitochondria, and FK866 alters NAD homeostasis within the organelle. Here, we show that FK866-dependent reduction of the NAD contents is paralleled by a concomitant increase of ATP in various cell types, in keeping with ATP utilization for NAD resynthesis. We also show that poly- and mono(ADP-ribose) transferases rather than Sirt-1 are responsible for NAD depletion in HeLa cells exposed to FK866. Mass spectrometry reveals that the drug distributes in the cytosolic and mitochondrial compartment. However, the cytoplasmic but not the mitochondrial NAD pool is reduced upon acute or chronic exposure to the drug. Accordingly, Nampt does not localize within the organelles and their bioenergetics is not affected by the drug. In the mouse, FK866-dependent reduction of NAD contents in various organs is prevented by inhibitors of poly(ADP-ribose) polymerases or the NAD precursor kynurenine. For the first time, our data indicate that mitochondria lack the canonical NAD rescue pathway, broadening current understanding of cellular bioenergetics.
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Affiliation(s)
- Maria Pittelli
- Department of Preclinical and Clinical Pharmacology, University of Florence, 50139 Florence, Italy
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114
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Parvez A, Jyotsna M, Youssoufi MH, Hadda TB. Theoretical Calculations and Experimental Verification of the Antibacterial Potential of Some Monocyclic β-Lactams Containing Two Synergetic Buried Antibacterial Pharmacophore Sites. PHOSPHORUS SULFUR 2010. [DOI: 10.1080/10426500903095556] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Ali Parvez
- a Department of Chemistry , Rashtrasant Tukadoji Maharaj Nagpur University , Nagpur, India
| | - Meshram Jyotsna
- a Department of Chemistry , Rashtrasant Tukadoji Maharaj Nagpur University , Nagpur, India
| | - Moulay Hfid Youssoufi
- b Laboratoire de Chimie des Matériaux, Faculté des Sciences , Université Mohammed Premier , Oujda, Morocco
| | - Taibi Ben Hadda
- b Laboratoire de Chimie des Matériaux, Faculté des Sciences , Université Mohammed Premier , Oujda, Morocco
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115
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Synthesis, characterization and antitumor activity of Cu(II), Co(II), Zn(II) and Mn(II) complex compounds with aminothiazole acetate derivative. OPEN CHEM 2010. [DOI: 10.2478/s11532-010-0022-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractThis paper presents the synthesis of complex compounds of type [M(L1)2], where M(II)= Cu (1), Co (2), Zn (3), L1=2-aminothiazole-4-acetate and [Mn(L1)2(H2O)] (4) using ethyl 2-(2-aminothiazole-4-yl) acetate (L), and characterization by elemental analysis, magnetic susceptibilities, IR, 1H-NMR, UV-Vis spectroscopy and for [Mn(L1)2(H2O)] also by X-ray diffraction. In vitro cytotoxicity studies were performed on human cervix adenocarcinoma, HeLa cells. The antitumor selectivity was assessed using normal human peripheral blood mononuclear cells, PBMC as control.
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116
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Schwarcz R, Guidetti P, Sathyasaikumar KV, Muchowski PJ. Of mice, rats and men: Revisiting the quinolinic acid hypothesis of Huntington's disease. Prog Neurobiol 2010; 90:230-45. [PMID: 19394403 PMCID: PMC2829333 DOI: 10.1016/j.pneurobio.2009.04.005] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2009] [Accepted: 04/17/2009] [Indexed: 12/31/2022]
Abstract
The neurodegenerative disease Huntington's disease (HD) is caused by an expanded polyglutamine (polyQ) tract in the protein huntingtin (htt). Although the gene encoding htt was identified and cloned more than 15 years ago, and in spite of impressive efforts to unravel the mechanism(s) by which mutant htt induces nerve cell death, these studies have so far not led to a good understanding of pathophysiology or an effective therapy. Set against a historical background, we review data supporting the idea that metabolites of the kynurenine pathway (KP) of tryptophan degradation provide a critical link between mutant htt and the pathophysiology of HD. New studies in HD brain and genetic model organisms suggest that the disease may in fact be causally related to early abnormalities in KP metabolism, favoring the formation of two neurotoxic metabolites, 3-hydroxykynurenine and quinolinic acid, over the related neuroprotective agent kynurenic acid. These findings not only link the excitotoxic hypothesis of HD pathology to an impairment of the KP but also define new drug targets and therefore have direct therapeutic implications. Thus, pharmacological normalization of the imbalance in brain KP metabolism may provide clinical benefits, which could be especially effective in early stages of the disease.
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Affiliation(s)
- Robert Schwarcz
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, USA.
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117
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Modulation of the Kynurenine Pathway for the Potential Treatment of Neurodegenerative Diseases. TOPICS IN MEDICINAL CHEMISTRY 2010. [DOI: 10.1007/7355_2010_9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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118
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Costantino G. New promises for manipulation of kynurenine pathway in cancer and neurological diseases. Expert Opin Ther Targets 2009; 13:247-58. [PMID: 19236242 DOI: 10.1517/14728220802665734] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND The kynurenine pathway (KP), the primary route of tryptophan degradation in mammalian cells, consists of a cascade of enzymatic reactions eventually leading to NAD(+) formation. Many metabolites along the route have biological activities, especially in the nervous and immune systems. OBJECTIVE/METHODS This review focuses on three therapeutic areas, tumor immunoediting, schizophrenia, and Huntington's disease, apparently disconnected but linked by preliminary proof-of-concept of KP involvement. The potential embedded in drug discovery programs aimed at the identification of selective inhibitors with optimized pharmacodynamic and pharmacokinetic properties for human studies is discussed. RESULTS/CONCLUSIONS Recent advances have shifted the attention on the kynurenine pathway from a scientific curiosity to a clinically relevant collection of targets. A relatively large number of ligands able to interfere with individual enzymes of the pathway have been made available, but none have so far proceeded into advanced clinical studies.
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Affiliation(s)
- Gabriele Costantino
- Università degli Studi di Parma, Dipartimento Farmaceutico, Via GP Usberti 27/A-Campus Universitario, 43100 Parma, Italy.
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119
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Sukdolak S, Solujić S, Manojlović N, Vuković N, Krstić LJ. Hantzsch reaction of 3-(2-bromoacetyl)-4-hydroxy-chromen-2-one. Synthesis of 3-(thiazol-4-yl)-4-hydroxy coumarines. J Heterocycl Chem 2009. [DOI: 10.1002/jhet.5570410418] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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120
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Miu J, Ball HJ, Mellor AL, Hunt NH. Effect of indoleamine dioxygenase-1 deficiency and kynurenine pathway inhibition on murine cerebral malaria. Int J Parasitol 2008; 39:363-70. [PMID: 19000912 DOI: 10.1016/j.ijpara.2008.10.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2008] [Revised: 09/10/2008] [Accepted: 10/03/2008] [Indexed: 11/28/2022]
Abstract
Cerebral malaria (CM) can be a fatal manifestation of Plasmodium falciparum infection. In this study, two different approaches were used to examine the role of indoleamine 2,3-dioxygenase-1 (IDO-1) and its metabolites in the development of murine CM. Mice genetically deficient in IDO-1 were not protected against CM, but partial protection was observed in C57BL/6 mice treated with Ro 61-8048, an inhibitor of kynurenine-3-hydroxylase. This protection was associated with suppressed levels of picolinic acid (PA) within the brain, but not with changes in the levels of kynurenic acid (KA) or quinolinic acid (QA). These data suggest that although IDO-1 is not directly involved in the pathogenesis of CM in C57BL/6 mice, the production of the kynurenine pathway metabolite PA may contribute to the development of murine CM.
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Affiliation(s)
- Jenny Miu
- Molecular Immunopathology Unit, Bosch Institute and School of Medical Sciences, University of Sydney, NSW, Australia
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121
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Vukovic N, Sukdolak S, Solujic S, Milosevic T. Synthesis and antimicrobial evaluation of some novel 2-aminothiazole derivatives of 4-hydroxy-chromene-2-one. Arch Pharm (Weinheim) 2008; 341:491-6. [PMID: 18623301 DOI: 10.1002/ardp.200700215] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Syntheses of 2-aminothiazole derivatives of 4-hydroxy-chromene-2-one 2c-10c are reported in this paper. These compounds 2c-10c were prepared from 3-(2-bromoacetyl)-4-hydroxy-chromene-2-one 1 and corresponding thiourea derivatives 2b-10b using Hantzsch reaction. The structures of all compounds were confirmed by IR and( 1)H-NMR spectroscopy and elemental analyses. The molecules 2c-10c were evaluated for in vitro antimicrobial activity against ten bacteria and twelve fungi. All tested compounds exhibited antibacterial and antifungal activity.
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Affiliation(s)
- Nenad Vukovic
- Faculty of Science, Department of Chemistry, Laboratory for Biochemistry, University of Kragujevac, Kragujevac, Serbia.
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122
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Abstract
L-kynurenine is an intermediate in the pathway of the metabolism of L-tryptophan to nicotinic acid. L-kynurenine is formed in the mammalian brain (40%) and is taken up from the periphery (60%), indicating that it can be transported across the BBB. It was discovered some 30 years ago that compounds in the kynurenine family have neuroactive properties. L-kynurenine, the central agent of this pathway, can be converted into two other important compounds: the neuroprotective kynurenic acid and the neurotoxic quinolinic acid. Kynurenines have been shown to be involved in many diverse physiological and pathological processes. There are a number of neurodegenerative disorders whose pathogenesis has been demonstrated to involve multiple imbalances of the kynurenine pathway metabolism. This review summarizes the main steps of the kynurenine pathway under normal conditions, discusses the metabolic disturbances and changes in this pathway in certain neurodegenerative disorders, and finally introduces the therapeutic possibilities with kynurenines.
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Affiliation(s)
- Hermina Robotka
- University of Szeged, Department of Physiology, Anatomy & Neuroscience, POB 533, and,Department of Neurology, POB 427, H-6701 Szeged, Hungary
| | - József Toldi
- University of Szeged, Department of Physiology, Anatomy & Neuroscience, POB 533, H-6701 Szeged, Hungary
| | - László Vécsei
- University of Szeged, Department of Neurology, POB 427, H-6701 Szeged, Hungary
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123
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Giorgini F, Möller T, Kwan W, Zwilling D, Wacker JL, Hong S, Tsai LCL, Cheah CS, Schwarcz R, Guidetti P, Muchowski PJ. Histone deacetylase inhibition modulates kynurenine pathway activation in yeast, microglia, and mice expressing a mutant huntingtin fragment. J Biol Chem 2007; 283:7390-400. [PMID: 18079112 DOI: 10.1074/jbc.m708192200] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The kynurenine pathway of tryptophan degradation is hypothesized to play an important role in Huntington disease, a neurodegenerative disorder caused by a polyglutamine expansion in the protein huntingtin. Neurotoxic metabolites of the kynurenine pathway, generated in microglia and macrophages, are present at increased levels in the brains of patients and mouse models during early stages of disease, but the mechanism by which kynurenine pathway up-regulation occurs in Huntington disease is unknown. Here we report that expression of a mutant huntingtin fragment was sufficient to induce transcription of the kynurenine pathway in yeast and that this induction was abrogated by impairing the activity of the histone deacetylase Rpd3. Moreover, numerous genetic suppressors of mutant huntingtin toxicity that are functionally unrelated converged unexpectedly on the kynurenine pathway, supporting a critical role for the kynurenine pathway in mediating mutant huntingtin toxicity in yeast. Histone deacetylase-dependent regulation of the kynurenine pathway was also observed in a mouse model of Huntington disease, in which treatment with a neuroprotective histone deacetylase inhibitor blocked activation of the kynurenine pathway in microglia expressing a mutant huntingtin fragment in vitro and in vivo. These findings suggest that a mutant huntingtin fragment can perturb transcriptional programs in microglia, and thus implicate these cells as potential modulators of neurodegeneration in Huntington disease that are worthy of further investigation.
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Affiliation(s)
- Flaviano Giorgini
- Department of Pharmacology, University of Washington, Seattle, Washington 98195, USA
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124
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125
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Poeggeler B, Rassoulpour A, Wu HQ, Guidetti P, Roberts RC, Schwarcz R. Dopamine receptor activation reveals a novel, kynurenate-sensitive component of striatal N-methyl-D-aspartate neurotoxicity. Neuroscience 2007; 148:188-97. [PMID: 17629627 PMCID: PMC2034343 DOI: 10.1016/j.neuroscience.2007.05.033] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2007] [Revised: 05/04/2007] [Accepted: 05/07/2007] [Indexed: 11/24/2022]
Abstract
The N-methyl-d-aspartate (NMDA) subtype of glutamate receptors plays an important role in brain physiology, but excessive receptor stimulation results in seizures and excitotoxic nerve cell death. NMDA receptor-mediated neuronal excitation and injury can be prevented by high, non-physiological concentrations of the neuroinhibitory tryptophan metabolite kynurenic acid (KYNA). Here we report that endogenous KYNA, which is formed in and released from astrocytes, controls NMDA receptors in vivo. This was revealed with the aid of the dopaminergic drugs d-amphetamine and apomorphine, which cause rapid, transient decreases in striatal KYNA levels in rats. Intrastriatal injections of the excitotoxins NMDA or quinolinate (but not the non-NMDA receptor agonist kainate) at the time of maximal KYNA reduction resulted in two- to threefold increases in excitotoxic lesion size. Pre-treatment with a kynurenine 3-hydroxylase inhibitor or with dopamine receptor antagonists, i.e., two classes of pharmacological agents that prevented the reduction in brain KYNA caused by dopaminergic stimulation, abolished the potentiation of neurotoxicity. Thus, the present study identifies a previously unappreciated role of KYNA as a functional link between dopamine receptor stimulation and NMDA neurotoxicity in the striatum.
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Affiliation(s)
- B Poeggeler
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, P.O. Box 21247, Baltimore, MD 21228, USA
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126
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Kazantsev AG. Developing a neuroprotective therapy for Parkinson’s and Huntington’s diseases. Expert Opin Ther Pat 2007. [DOI: 10.1517/13543776.17.2.159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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127
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Siddiqui HL, Zia-Ur-Rehman M, Ahmad N, Weaver GW, Lucas PD. Synthesis and Antibacterial Activity of Bis[2-amino-4-phenyl-5-thiazolyl] Disulfides. Chem Pharm Bull (Tokyo) 2007; 55:1014-7. [PMID: 17603192 DOI: 10.1248/cpb.55.1014] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Different dimeric disulfides, having the basic skeleton of bis[2-amino-4-phenyl-5-thiazolyl] disulfides were synthesized in a straightforward manner from acetophenones. 2-Amino-4-phenyl-1,3-thiazoles were prepared by the reaction of thiourea with substituted acetophenones in the presence of iodine which were then converted to the title compounds. All the compounds were subjected to preliminary evaluation for their biological activity against Gram positive and Gram negative bacteria. Some of the assayed compounds showed marked activity against Bacillus cereus and Pseudomonas aeruginosa.
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128
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Finkbeiner S, Maria Cuervo A, Morimoto RI, Muchowski PJ. Disease-modifying pathways in neurodegeneration. J Neurosci 2006; 26:10349-57. [PMID: 17035516 PMCID: PMC6674695 DOI: 10.1523/jneurosci.3829-06.2006] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Affiliation(s)
- Steven Finkbeiner
- Gladstone Institute of Neurological Disease and
- Departments of Physiology
- Neurology, and
| | - Ana Maria Cuervo
- Department of Anatomy and Structural Biology, Marion Bessin Liver Research Center, Albert Einstein College of Medicine, Bronx, New York 10461, and
| | - Richard I. Morimoto
- Department of Biochemistry, Molecular Biology, and Cell Biology, Rice Institute for Biomedical Research, Northwestern University, Evanston, Illinois 60208
| | - Paul J. Muchowski
- Gladstone Institute of Neurological Disease and
- Neurology, and
- Biochemistry and Biophysics, University of California, San Francisco, San Francisco, California 94158
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129
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Guidetti P, Bates GP, Graham RK, Hayden MR, Leavitt BR, MacDonald ME, Slow EJ, Wheeler VC, Woodman B, Schwarcz R. Elevated brain 3-hydroxykynurenine and quinolinate levels in Huntington disease mice. Neurobiol Dis 2006; 23:190-7. [PMID: 16697652 DOI: 10.1016/j.nbd.2006.02.011] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2005] [Revised: 02/08/2006] [Accepted: 02/27/2006] [Indexed: 11/29/2022] Open
Abstract
The brain levels of the endogenous excitotoxin quinolinic acid (QUIN) and its bioprecursor, the free radical generator 3-hydroxykynurenine (3-HK), are elevated in early stage Huntington disease (HD). We now examined the status of these metabolites in three mouse models of HD. In R6/2 mice, 3-HK levels were significantly and selectively elevated in the striatum, cortex and cerebellum starting at 4 weeks of age. In contrast, both 3-HK and QUIN levels were increased in the striatum and cortex of the full-length HD models, beginning at 8 months (YAC128) and 15 months (Hdh(Q92) and Hdh(Q111)), respectively. No changes were seen in 13-month-old shortstop mice, which show no signs of motor or cognitive dysfunction or selective neuropathology. These results demonstrate both important parallels and intriguing differences in the progressive neurochemical changes in these HD mouse models and support the hypothesis that QUIN may play a role in the striatal and cortical neurodegeneration of HD.
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Affiliation(s)
- Paolo Guidetti
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD 21228, USA
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130
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Synthesis of new 3-(2-aminothiazol-4-yl)-4-hydroxy-2H-chromen-2-one derivatives. JOURNAL OF THE SERBIAN CHEMICAL SOCIETY 2006. [DOI: 10.2298/jsc0606581s] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Aminothiazole derivatives of 4-hydroxy-2H-chromen-2-one were prepared by the Hantzsch reaction1 using 3-(2-bromoacetyl)-4-hydroxy-2H-chromen-2-one and thiourea derivatives. Starting compound for this synthesis 3-(2-bromoacetyl)-4-hydroxy- 2H-chromen-2-one (1) was prepared previously.2 Also, for this synthesis we used thiourea derivatives (2a-j) as compounds which possess groups with biological activity. Reactions are carried out in refluxing ethanol for a period of 30 - 45 min. Final products (3a-j) are obtained in a high yield. Chemical structure of the obtained compounds was confirmed by elemental and structural analysis (IR and 1H NMR spectroscopy).
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131
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Samadi P, Grégoire L, Rassoulpour A, Guidetti P, Izzo E, Schwarcz R, Bédard PJ. Effect of kynurenine 3-hydroxylase inhibition on the dyskinetic and antiparkinsonian responses to levodopa in Parkinsonian monkeys. Mov Disord 2005; 20:792-802. [PMID: 15954116 DOI: 10.1002/mds.20596] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Homeostatic interactions between dopamine and glutamate are central to the normal physiology of the basal ganglia. This relationship is altered in Parkinsonism and in levodopa-induced dyskinesias (LID), resulting in an upregulation of corticostriatal glutamatergic function. Kynurenic acid (KYNA), a tryptophan metabolite with antagonist activity at ionotropic glutamate receptors and the capability to inhibit glutamate release presynaptically, might therefore be of therapeutic value in LID. To evaluate this hypothesis, we used a pharmacological tool, the kynurenine 3-hydroxylase inhibitor Ro 61-8048, which raises KYNA levels acutely. Ro 61-8048 was tested in MPTP cynomolgus monkeys with a stable parkinsonian syndrome and reproducible dyskinesias after each dose of levodopa. Serum and CSF concentrations of KYNA and its precursor kynurenine increased dose-dependently after Ro 61-8048 administration, alone or in combination with levodopa. Coadministration of Ro 61-8048 with levodopa produced a moderate but significant reduction in the severity of dyskinesias while maintaining the motor benefit. These results suggest that elevation of KYNA levels through inhibition of kynurenine 3-hydroxylase constitutes a promising novel approach for managing LID in Parkinson's disease.
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Affiliation(s)
- Pershia Samadi
- Centre de Recherche en Neurosciences, Centre Hospitalier Universitaire de Québec, Québec, Canada
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132
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Clark CJ, Mackay GM, Smythe GA, Bustamante S, Stone TW, Phillips RS. Prolonged survival of a murine model of cerebral malaria by kynurenine pathway inhibition. Infect Immun 2005; 73:5249-51. [PMID: 16041050 PMCID: PMC1201246 DOI: 10.1128/iai.73.8.5249-5251.2005] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
C57BL/6J mice infected with Plasmodium berghei ANKA develop neurological dysfunction and die within 7 days of infection. We show that treatment of infected mice with a kynurenine-3-hydroxylase inhibitor prevents them from developing neurological symptoms and extends their life span threefold until severe anemia develops.
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Affiliation(s)
- Catherine J Clark
- Division of Infection and Immunity, Institute of Biomedical and Life Sciences, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ, United Kingdom.
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133
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Moroni F, Cozzi A, Carpendo R, Cipriani G, Veneroni O, Izzo E. Kynurenine 3-mono-oxygenase inhibitors reduce glutamate concentration in the extracellular spaces of the basal ganglia but not in those of the cortex or hippocampus. Neuropharmacology 2005; 48:788-95. [PMID: 15829251 DOI: 10.1016/j.neuropharm.2004.10.019] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2004] [Revised: 09/11/2004] [Accepted: 10/01/2004] [Indexed: 11/20/2022]
Abstract
Kynurenine 3-mono-oxygenase (KMO, kynurenine hydroxylase) inhibitors increase brain kynurenic acid (KYNA) synthesis and cause pharmacological actions possibly mediated by a reduced activity of excitatory synapses. We used in vivo microdialysis and passive avoidance to study the effects of local KYNA or systemic KMO inhibitor administration on glutamate (GLU) neurotransmission. Local application of KYNA (30-100 nM) through reverse microdialysis reduced GLU content in caudate and cortical dialysates by 75 and 55%, respectively. No changes were found in the hippocampus. Systemic administration of Ro 61-8048 (4-40 mg/kg) increased KYNA levels in dialysates obtained from the cortex (from 10.3 +/- 1.9 to 45.5 +/- 15 nM), caudate (from 2.4 +/- 0.8 to 9.5 +/- 0.9 nM) and hippocampus (from 7.7 +/- 1.7 to 19.2 +/- 3.5 nM). It also caused a parallel robust decrease in GLU levels in the dialysates collected from the caudate (from 2.2 +/- 0.5 to 0.63 +/- 0.05 microM) but not in those collected from the parietal cortex or the hippocampus. In a passive avoidance paradigm, the administration of the NMDA receptor antagonist MK-801 (0.1 mg/kg) reduced, while Ro 61-8048 (4-80 mg/kg) did not change the latency time of entering into the dark compartment on the recall trial. Our data show that KMO inhibitors increase brain KYNA synthesis and selectively reduce GLU extracellular concentration in the basal ganglia.
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Affiliation(s)
- F Moroni
- Department of Pharmacology, University of Florence, Viale Pieraccini 6, 50134 Firenze, Italy.
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134
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Rassoulpour A, Wu HQ, Ferre S, Schwarcz R. Nanomolar concentrations of kynurenic acid reduce extracellular dopamine levels in the striatum. J Neurochem 2005; 93:762-5. [PMID: 15836634 DOI: 10.1111/j.1471-4159.2005.03134.x] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Precise regulation of dopaminergic activity is of obvious importance for the physiology and pathology of basal ganglia. We report here that nanomolar concentrations of the astrocyte-derived neuroinhibitory metabolite kynurenic acid (KYNA) potently reduce the extracellular levels of striatal dopamine in unanesthetized rats in vivo. This effect, which is initiated by the KYNA-induced blockade of alpha7 nicotinic acetylcholine receptors, highlights the functional relevance of glia-neuron interactions in the striatum and indicates that even modest increases in the brain levels of endogenous KYNA are capable of interfering with dopaminergic neurotransmission.
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Affiliation(s)
- Arash Rassoulpour
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, Maryland 21218, USA
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135
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Giorgini F, Guidetti P, Nguyen Q, Bennett SC, Muchowski PJ. A genomic screen in yeast implicates kynurenine 3-monooxygenase as a therapeutic target for Huntington disease. Nat Genet 2005; 37:526-31. [PMID: 15806102 PMCID: PMC1449881 DOI: 10.1038/ng1542] [Citation(s) in RCA: 270] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2004] [Accepted: 03/02/2005] [Indexed: 11/09/2022]
Abstract
Huntington disease is a fatal neurodegenerative disorder caused by expansion of a polyglutamine tract in the protein huntingtin (Htt), which leads to its aggregation in nuclear and cytoplasmic inclusion bodies. We recently identified 52 loss-of-function mutations in yeast genes that enhance the toxicity of a mutant Htt fragment. Here we report the results from a genome-wide loss-of-function suppressor screen in which we identified 28 gene deletions that suppress toxicity of a mutant Htt fragment. The suppressors are known or predicted to have roles in vesicle transport, vacuolar degradation, transcription and prion-like aggregation. Among the most potent suppressors was Bna4 (kynurenine 3-monooxygenase), an enzyme in the kynurenine pathway of tryptophan degradation that has been linked directly to the pathophysiology of Huntington disease in humans by a mechanism that may involve reactive oxygen species. This finding is suggestive of a conserved mechanism of polyglutamine toxicity from yeast to humans and identifies new candidate therapeutic targets for the treatment of Huntington disease.
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Affiliation(s)
- Flaviano Giorgini
- Department of Pharmacology, University of Washington, Seattle, Washington 98195, USA
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136
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Richter A, Hamann M. The kynurenine 3-hydroxylase inhibitor Ro 61-8048 improves dystonia in a genetic model of paroxysmal dyskinesia. Eur J Pharmacol 2004; 478:47-52. [PMID: 14555184 DOI: 10.1016/j.ejphar.2003.08.038] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The effects of the novel kynurenine 3-hydroxylase inhibitor 3,4-dimethoxy-N-[4-(3-nitrophenyl)thiazol-2-yl]benzenesulfonamide (Ro 61-8048) on severity of dystonia were examined in dt(sz) mutant hamsters, an animal model of paroxysmal dystonia, in which stress precipitates dystonic episodes. Ro 61-8048 (50, 100 and 150 mg/kg i.p.) significantly reduced the severity of dystonia in dt(sz) hamsters without leading to marked central side effects. Determinations of kynurenic acid concentrations in brain homogenates demonstrated that Ro 61-8048 (100 mg/kg i.p.) provoked a two- to threefold increase of the endogeneous broad spectrum glutamate receptor antagonist kynurenic acid in the striatum, cerebellum and brainstem of mutant hamsters. The antidystonic efficacy of Ro 61-8048 at well-tolerated doses suggests that kynurenine 3-hydroxylase inhibitors should be considered as new therapeutic candidates for the treatment of dyskinesias.
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Affiliation(s)
- Angelika Richter
- Institute of Pharmacology and Toxicology, School of Veterinary Medicine, Freie Universität Berlin, Koserstr. 20, 14195 Berlin, Germany.
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137
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Metwally MA, Abdel-Latif E, Amer FA, Kaupp G. Versatile 2-amino-4-substituted-1,3-thiazoles: synthesis and reactions. J Sulphur Chem 2004. [DOI: 10.1080/17415990310001632365] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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138
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Klivényi P, Toldi J, Vécsei L. Kynurenines in neurodegenerative disorders: therapeutic consideration. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2004; 541:169-83. [PMID: 14977214 DOI: 10.1007/978-1-4419-8969-7_10] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Affiliation(s)
- Péter Klivényi
- Department of Neurology, University of Szeged POB 427, H-6701, Szeged, Hungary
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139
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Synthesis of some 3-(thiazol- 4-yl)-4-hydroxy coumarines. JOURNAL OF THE SERBIAN CHEMICAL SOCIETY 2004. [DOI: 10.2298/jsc0405319s] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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140
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Pellicciari R, Amori L, Costantino G, Giordani A, Macchiarulo A, Mattoli L, Pevarello P, Speciale C, Varasi M. Modulation of the Kynurine Pathway of Tryptophan Metabolism in Search for Neuroprotective Agents. Focus on Kynurenine-3-Hydroxylase. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2003; 527:621-8. [PMID: 15206781 DOI: 10.1007/978-1-4615-0135-0_71] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A novel potent and selective kynurenine-3-hydroxylase inhibitor is descibed along a preliminary evaluation in a in vivo gerbil model of its ability to increase the kynurenine and kynurenic acid concentration in both plasma and brain. These data support the notion that kynurenine-3-hydroxylase inhibitors may have a sustained therapeutic potential in those diseases characterized by unbalance in the QUIN/KYNA branches of the kynurenine pathway.
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Affiliation(s)
- Roberto Pellicciari
- Dipartimento di Chimica e Tecnologia del Farmaco, Università di Perugia, Via del Liceo 1, 06123 Perugia, Italy
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141
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Takikawa O, Truscott RJW, Fukao M, Miwa S. Age-related nuclear cataract and indoleamine 2,3-dioxygenase-initiated tryptophan metabolism in the human lens. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2003; 527:277-85. [PMID: 15206741 DOI: 10.1007/978-1-4615-0135-0_31] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Tryptophan-derived UV filters (kynurenine and 3-hydroxylkynurenine glucoside) have recently been shown to bind to human lens proteins. These UV filter adducts increase in amount with age and appear to be mainly responsible for the yellowing of the lens in man. On the basis of research performed in other tissues, it has been assumed that indoleamine 2,3-dioxygenase (IDO) may be the first and probably rate-limiting enzyme in UV filter biosynthesis. In this study, 25 human lenses were examined by a reliable and sensitive assay method with a monoclonal antibody specific for IDO. IDO activity was detected in all lenses ranging from 26 to 80 years, and there was no clear relationship of IDO activity with age. The mean activity was 0.85 + 0.49 nmol of kynurenine/h/lens. The level in the iris/ciliary body was negligible (<0.05 nmol of kynurenine/h). The lens IDO activity is consistent with UV filter turnover values obtained previously. These findings indicate that IDO is the first enzyme in the UV filter pathway and that UV filter biosynthesis is active even in aged lenses. Yellowing of the aged lens may therefore be preventable by drug-induced suppression of IDO activity.
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Affiliation(s)
- Osamu Takikawa
- Australian Cataract Research Foundation, University of Wollongong, NSW 2522, Australia
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142
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Moroni F, Carpenedo R, Cozzi A, Meli E, Chiarugi A, Pellegrini-Giampietro DE. Studies on the neuroprotective action of kynurenine mono-oxygenase inhibitors in post-ischemic brain damage. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2003; 527:127-36. [PMID: 15206725 DOI: 10.1007/978-1-4615-0135-0_15] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Kynurenine 3-mono-oxygenase (KMO) inhibitors facilitate kynurenic acid (KYNA) neosynthesis and reduce the formation of 3OH-kynurenine (3-HK) and quinolinic acid (QUIN). They also attenuate post-ischemic brain damage and decrease glutamate (Glu) content in brain extracellular spaces. To investigate KMO mechanism(s) of neuroprotection, we performed experiments in gerbils subjected to bilateral carotid occlusion and in organotypic rat hippocampal slice cultures exposed to oxygen and glucose deprivation (OGD). In gerbils, direct application of KYNA (100 nM, through reverse microdialysis in the hippocampus) completely prevented the increase in Glu output induced by transient (5 min) occlusion of the carotids. In rat hippocampal slices exposed for 30 min to OGD, KMO inhibitors (m-nitrobenzoyl)-alanine (mNBA, 30-100 microM) or 3,4-dimethoxy-[-N-4-(nitrophenyl)thiazol-2yl]-benzenesulfonamide (Ro 61-8048, 1-10 microM) reduced post-ischemic neuronal death and increased KYNA concentrations in the incubation medium. KYNA may antagonize glycineb or alpha7 nicotinic acetylcholine receptors but the concentrations in the incubation medium never reached values that could efficiently antagonize receptor function. On the contrary, 3-HK (1-10 microM) added to slices exposed to OGD in the presence of KMO inhibitors completely prevented the neuroprotective effects of the inhibitors. Our findings suggest that KMO inhibitors reduce OGD-induced pyramidal cell death by decreasing 3-HK (and possibly QUIN) synthesis.
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Affiliation(s)
- Flavio Moroni
- Dipartimento di Farmacologia Preclinica e Clinica, Università di Firenze, Viale Pieraccini 6, 50139 Firenze, Italy.
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143
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Schwarcz R, Pellicciari R. Manipulation of brain kynurenines: glial targets, neuronal effects, and clinical opportunities. J Pharmacol Exp Ther 2002; 303:1-10. [PMID: 12235226 DOI: 10.1124/jpet.102.034439] [Citation(s) in RCA: 418] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Degradation of the essential amino acid tryptophan along the kynurenine pathway (KP) yields several neuroactive intermediates, including the free radical generator 3-hydroxykynurenine, the excitotoxic N-methyl-D-aspartate (NMDA) receptor agonist quinolinic acid, and the NMDA and alpha7 nicotinic acetylcholine receptor antagonist kynurenic acid. The ambient levels of these compounds are determined by several KP enzymes, which in the brain are preferentially localized in astrocytes and microglial cells. Normal fluctuations in the brain levels of neuroactive KP intermediates might modulate several neurotransmitter systems. Impairment of KP metabolism is functionally significant and occurs in a variety of diseases that affect the brain. Pharmacological agents targeting specific KP enzymes are now available to manipulate the concentration of neuroactive KP intermediates in the brain. These compounds can be used to normalize KP defects, show remarkable efficacy in animal models of central nervous system disorders, and offer novel therapeutic opportunities.
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Affiliation(s)
- Robert Schwarcz
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, USA.
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144
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Carpenedo R, Meli E, Peruginelli F, Pellegrini-Giampietro DE, Moroni F. Kynurenine 3-mono-oxygenase inhibitors attenuate post-ischemic neuronal death in organotypic hippocampal slice cultures. J Neurochem 2002; 82:1465-71. [PMID: 12354294 DOI: 10.1046/j.1471-4159.2002.01090.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Kynurenine 3-mono-oxygenase (KMO) inhibitors reduce 3-hydroxykynurenine (3-HK) and quinolinic acid (QUIN) neosynthesis and facilitate kynurenine metabolism towards kynurenic acid (KYNA) formation. They also reduce tissue damage in models of focal or transient global cerebral ischemia in vivo. We used organotypic hippocampal slice cultures exposed to oxygen and glucose deprivation (OGD) to investigate KMO mechanism(s) of neuroprotective activity. Exposure of the slices to 30 min of OGD caused CA1 pyramidal cell death and significantly decreased the amount of KYNA released in the incubation medium. The KMO inhibitors (m-nitrobenzoyl)-alanine (30-100 micro m) or 3,4-dimethoxy-[-N-4-(nitrophenyl)thiazol-2yl]-benzenesulfonamide (1-10 micro m) reduced post-ischemic neuronal death and increased KYNA concentrations in slice incubation media. The maximal concentration of KYNA detected in the incubation media of slices treated with KMO inhibitors was approximately 50 nm and was too low to efficiently interact with alpha7 nicotinic acetylcholine receptors or with the glycineb site of N-methyl-d-aspartate (NMDA) receptors. On the other hand, the addition of either 3-HK or QUIN (1-10 micro m) to OGD-exposed hippocampal slices prevented the neuroprotective activity of KMO inhibitors. Our results suggest that KMO inhibitors reduce the neuronal death found in the CA1 region of organotypic hippocampal slices exposed to 30 min of OGD by decreasing the local synthesis of 3-HK and QUIN.
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Affiliation(s)
- Raffaella Carpenedo
- Dipartimento di Farmacologia Preclinica e Clinica, Università di Firenze, Firenze, Italy
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145
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Stone TW, Darlington LG. Endogenous kynurenines as targets for drug discovery and development. Nat Rev Drug Discov 2002; 1:609-20. [PMID: 12402501 DOI: 10.1038/nrd870] [Citation(s) in RCA: 573] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The kynurenine pathway is the main pathway for tryptophan metabolism. It generates compounds that can modulate activity at glutamate receptors and possibly nicotinic receptors, in addition to some as-yet-unidentified sites. The pathway is in a unique position to regulate other aspects of the metabolism of tryptophan to neuroactive compounds, and also seems to be a key factor in the communication between the nervous and immune systems. It also has potentially important roles in the regulation of cell proliferation and tissue function in the periphery. As a result, the pathway presents a multitude of potential sites for drug discovery in neuroscience, oncology and visceral pathology.
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Affiliation(s)
- Trevor W Stone
- Institute of Biomedical and Life Sciences, West Medical Building, University of Glasgow, Glasgow G12 8QQ, UK.
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146
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Ferraris D, Young B, Cox C, Dudding T, Drury WJ, Ryzhkov L, Taggi AE, Lectka T. Catalytic, enantioselective alkylation of alpha-imino esters: the synthesis of nonnatural alpha-amino acid derivatives. J Am Chem Soc 2002; 124:67-77. [PMID: 11772063 DOI: 10.1021/ja016838j] [Citation(s) in RCA: 140] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Methodology for the practical synthesis of nonnatural amino acids has been developed through the catalytic, asymmetric alkylation of alpha-imino esters and N,O-acetals by enol silanes, ketene acetals, alkenes, and allylsilanes using chiral transition metal-phosphine complexes as catalysts (1-5 mol %). The alkylation products, which are prepared with high enantioselectivity (up to 99% ee) and diastereoselectivity (up to 25:1/anti:syn), are protected nonnatural amino acids that represent potential precursors to natural products and pharmaceuticals. A kinetic analysis of the catalyzed reaction of alkenes with alpha-imino esters is presented to shed light on the mechanism of this reaction.
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Affiliation(s)
- Dana Ferraris
- Department of Chemistry, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA
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147
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Abstract
In just under 20 years the kynurenine family of compounds has developed from a group of obscure metabolites of the essential amino acid tryptophan into a source of intensive research, with postulated roles for quinolinic acid in neurodegenerative disorders, most especially the AIDS-dementia complex and Huntington's disease. One of the kynurenines, kynurenic acid, has become a standard tool for use in the identification of glutamate-releasing synapses, and has been used as the parent for several groups of compounds now being developed as drugs for the treatment of epilepsy and stroke. The kynurenines represent a major success in translating a basic discovery into a source of clinical understanding and therapeutic application, with around 3000 papers published on quinolinic acid or kynurenic acid since the discovery of their effects in 1981 and 1982. This review concentrates on some of the recent work most directly relevant to the understanding and applications of kynurenines in medicine.
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Affiliation(s)
- T W Stone
- Institute of Biomedical and Life Sciences, University West Medical Building, University of Glasgow, Glasgow G12 8QQ, UK.
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148
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Chiarugi A, Cozzi A, Ballerini C, Massacesi L, Moroni F. Kynurenine 3-mono-oxygenase activity and neurotoxic kynurenine metabolites increase in the spinal cord of rats with experimental allergic encephalomyelitis. Neuroscience 2001; 102:687-95. [PMID: 11226705 DOI: 10.1016/s0306-4522(00)00504-2] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Kynurenine 3-mono-oxygenase, one of the key enzymes of the "kynurenine pathway", catalyses the formation of 3-hydroxykynurenine and may direct the neo-synthesis of quinolinic and kynurenic acids. While 3-hydroxykynurenine and quinolinic acid have neurotoxic properties, kynurenic acid antagonizes excitotoxic neuronal death. Here we report that the expression and activity of kynurenine 3-mono-oxygenase significantly increased in the spinal cord of rats with experimental allergic encephalopathy, an experimental model of multiple sclerosis. As a consequence of this increase, the spinal cord content of 3-hydroxykynurenine and quinolinic acid reached neurotoxic levels. We also report that systemic administration of Ro 61-8048, a selective kynurenine 3-mono-oxygenase inhibitor, reduced the increase of both 3-hydroxykynurenine and quinolinic acid, and caused accumulation of kynurenic acid. In the brain and spinal cord of the controls, kynurenine 3-mono-oxygenase immunoreactivity was located in granules (probably mitochondria) present in the cytoplasm of both neurons and astroglial cells. In the spinal cord of rats with experimental allergic encephalopathy, however, cells with a very intense kynurenine 3-mono-oxygenase immunoreactivity, also able to express class II major histocompatibility complex and inducible nitric oxide synthase, were found in perivascular, subependymal and subpial locations. These cells (most probably macrophages) were responsible for the large increase in 3-hydroxykynurenine and quinolinic acid found in the spinal cords of affected animals. The results show that cells of the immune system are responsible for the increased formation of 3-hydroxykynurenine and quinolinic acid, two neurotoxic metabolites that accumulate in the central nervous system of rats with experimental allergic encephalomyelitis. They also demonstrate that selective kynurenine 3-mono-oxygenase inhibitors reduce the neo-synthesis of these toxins.
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Affiliation(s)
- A Chiarugi
- Department of Preclinical and Clinical Pharmacology, Viale Pieraccini 6, 50139, Florence, Italy
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149
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Abstract
The kynurenine pathway accounts for the metabolism of around 80% of non-protein tryptophan metabolism. It includes both an agonist (quinolinic acid) at NMDA receptors and an antagonist (kynurenic acid). Since their discovery, there has been a major development of kynurenic acid analogues as neuroprotectants for the treatment of stroke and neurodegenerative disease. Several prodrugs of kynurenic acid or its analogues that can be hydrolysed within the CNS are also available. More recently, the pathway itself has proved to be a valuable drug target, affected by agents which reduce the synthesis of quinolinic acid and increase the formation of kynurenic acid. The change in the balance of these, away from the excitotoxin and towards the neuroprotectant, has anticonvulsant and neuroprotective properties.
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Affiliation(s)
- T W Stone
- Institute of Biomedical & Life Sciences, West Medical Building, University of Glasgow, Glasgow G12 8QQ, Scotland, UK.
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150
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Takikawa O, Littlejohn TK, Truscott RJ. Indoleamine 2,3-dioxygenase in the human lens, the first enzyme in the synthesis of UV filters. Exp Eye Res 2001; 72:271-7. [PMID: 11180976 DOI: 10.1006/exer.2000.0951] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Tryptophan-derived UV filters have recently been shown to bind to human lens proteins. These UV filter adducts increase in amount with age and appear to be mainly responsible for the yellowing of the lens in man. On the basis of research performed in other tissues, it has been assumed that indoleamine 2,3-dioxygenase (IDO) may be the first and probably rate-limiting enzyme in UV filter biosynthesis. In this study, 25 human lenses were examined by a reliable and sensitive assay method with a monoclonal antibody specific for IDO. IDO activity was detected in all lenses ranging from 26 to 80 years, and there was no clear relationship of IDO activity with age. The mean activity was 0.85 +/- 0.49 nmol of kynurenine formed hr(-1)per lens. IDO expression was found to be localized in the anterior cortex of the lens with little or no activity in the posterior cortex or nucleus. The level in the iris/ciliary body was negligible (<0.05 nmol of kynurenine formed hr(-1)). The lens IDO activity is consistent with UV filter turnover values obtained previously. These findings indicate that IDO is the first enzyme in the UV filter pathway and that UV filter biosynthesis is active even in aged lenses. Yellowing of the aged lens may therefore be preventable by drug-induced suppression of lens IDO activity.
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Affiliation(s)
- O Takikawa
- Australian Cataract Research Foundation, University of Wollongong, Wollongong, NSW 2522, Australia.
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