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Fujikawa M, Ueda M, Maruyama K. Role of Kynurenine and Its Derivatives in the Neuroimmune System. Int J Mol Sci 2024; 25:7144. [PMID: 39000249 PMCID: PMC11241229 DOI: 10.3390/ijms25137144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2024] [Revised: 06/26/2024] [Accepted: 06/26/2024] [Indexed: 07/16/2024] Open
Abstract
In recent years, there has been a growing realization of intricate interactions between the nervous and immune systems, characterized by shared humoral factors and receptors. This interplay forms the basis of the neuroimmune system, the understanding of which will provide insights into the pathogenesis of neurological diseases, in which the involvement of the immune system has been overlooked. Kynurenine and its derivatives derived from tryptophan have long been implicated in the pathogenesis of various neurological diseases. Recent studies have revealed their close association not only with neurological disorders but also with sepsis-related deaths. This review provides an overview of the biochemistry of kynurenine and its derivatives, followed by a discussion of their role via the modulation of the neuroimmune system in various diseases.
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Affiliation(s)
- Makoto Fujikawa
- Department of Pharmacology, School of Medicine, Aichi Medical University, Nagakute 480-1195, Aichi, Japan
| | - Masashi Ueda
- Department of Pharmacology, School of Medicine, Aichi Medical University, Nagakute 480-1195, Aichi, Japan
| | - Kenta Maruyama
- Department of Pharmacology, School of Medicine, Aichi Medical University, Nagakute 480-1195, Aichi, Japan
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2
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Kondo T, Okada Y, Shizuya S, Yamaguchi N, Hatakeyama S, Maruyama K. Neuroimmune modulation by tryptophan derivatives in neurological and inflammatory disorders. Eur J Cell Biol 2024; 103:151418. [PMID: 38729083 DOI: 10.1016/j.ejcb.2024.151418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2023] [Revised: 05/02/2024] [Accepted: 05/03/2024] [Indexed: 05/12/2024] Open
Abstract
The nervous and immune systems are highly developed, and each performs specialized physiological functions. However, they work together, and their dysfunction is associated with various diseases. Specialized molecules, such as neurotransmitters, cytokines, and more general metabolites, are essential for the appropriate regulation of both systems. Tryptophan, an essential amino acid, is converted into functional molecules such as serotonin and kynurenine, both of which play important roles in the nervous and immune systems. The role of kynurenine metabolites in neurodegenerative and psychiatric diseases has recently received particular attention. Recently, we found that hyperactivity of the kynurenine pathway is a critical risk factor for septic shock. In this review, we first outline neuroimmune interactions and tryptophan derivatives and then summarized the changes in tryptophan metabolism in neurological disorders. Finally, we discuss the potential of tryptophan derivatives as therapeutic targets for neuroimmune disorders.
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Affiliation(s)
- Takeshi Kondo
- Department of Biochemistry, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Hokkaido 060-8636, Japan
| | - Yuka Okada
- Department of Ophthalmology, Wakayama Medical University School of Medicine, Wakayama 641-0012, Japan
| | - Saika Shizuya
- Department of Ophthalmology, Wakayama Medical University School of Medicine, Wakayama 641-0012, Japan
| | - Naoko Yamaguchi
- Department of Pharmacology, School of Medicine, Aichi Medical University, Aichi 480-1195, Japan
| | - Shigetsugu Hatakeyama
- Department of Biochemistry, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Hokkaido 060-8636, Japan
| | - Kenta Maruyama
- Department of Pharmacology, School of Medicine, Aichi Medical University, Aichi 480-1195, Japan.
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Verma K, Amitabh, Prasad DN, Reddy MPK, Kohli E. Kynurenines Dynamics in the Periphery and Central Nervous System Steers Behavioral Deficits in Rats under Hypobaric Hypoxia. ACS Chem Neurosci 2024; 15:1084-1095. [PMID: 38462729 DOI: 10.1021/acschemneuro.3c00632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2024] Open
Abstract
People travel to high-altitude regions as tourists, workers, and military personnel on duty. Despite the consistent 21% oxygen content in the atmosphere, ascending to higher altitudes results in a decrease in the partial pressure of oxygen, inducing a state known as hypobaric hypoxia (HH). HH is an environmental stress that is responsible for neuroinflammation and behavioral deficits (anxiety, depression, mood disturbance, etc.), but little is known about its metabolic pathways. The kynurenine pathway (KP) is a promising candidate to uncover the mysteries of HH stress, as it is an important regulator of the immune system and is associated with behavioral deficits. To investigate the role of KP under HH, the levels of KP metabolites in the serum, cerebrospinal fluid (CSF), and brain tissue (prefrontal cortex-PFC, neocortex, and hippocampus) of male Sprague-Dawley rats exposed to HH at 7620 m for 1, 3, and 7 days were estimated utilizing high-performance liquid chromatography (HPLC). The behavioral analogs for anxiety-like and depression-like behavior were assessed using the open field test and forced swim test, respectively. Upon HH exposure, crosstalk between the periphery and central nervous system and KP metabolite region-dependent differential expression in the brain were observed. KP metabolites showed a positive correlation with behavioral parameters. The results of our study are indicative that KP can be proposed as the etiology of behavioral deficits, and KP metabolite levels in serum or CSF can be used as plausible markers for anxiety-like and depression-like behaviors under HH stress with a scope of targeted therapeutic interventions.
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Affiliation(s)
- Kalyani Verma
- Department of Neurobiology, Defence Institute of Physiology and Allied Sciences, DRDO, Timarpur,Delhi 110054, India
| | - Amitabh
- Department of Neurobiology, Defence Institute of Physiology and Allied Sciences, DRDO, Timarpur,Delhi 110054, India
| | - Dipti N Prasad
- Department of Neurobiology, Defence Institute of Physiology and Allied Sciences, DRDO, Timarpur,Delhi 110054, India
| | - M Prasanna Kumar Reddy
- Department of Applied Physiology, Defence Institute of Physiology and Allied Sciences, DRDO, Timarpur, Delhi 110054, India
| | - Ekta Kohli
- Department of Neurobiology, Defence Institute of Physiology and Allied Sciences, DRDO, Timarpur,Delhi 110054, India
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Lodge S, Lawler NG, Gray N, Masuda R, Nitschke P, Whiley L, Bong SH, Yeap BB, Dwivedi G, Spraul M, Schaefer H, Gil-Redondo R, Embade N, Millet O, Holmes E, Wist J, Nicholson JK. Integrative Plasma Metabolic and Lipidomic Modelling of SARS-CoV-2 Infection in Relation to Clinical Severity and Early Mortality Prediction. Int J Mol Sci 2023; 24:11614. [PMID: 37511373 PMCID: PMC10380980 DOI: 10.3390/ijms241411614] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 07/10/2023] [Accepted: 07/15/2023] [Indexed: 07/30/2023] Open
Abstract
An integrative multi-modal metabolic phenotyping model was developed to assess the systemic plasma sequelae of SARS-CoV-2 (rRT-PCR positive) induced COVID-19 disease in patients with different respiratory severity levels. Plasma samples from 306 unvaccinated COVID-19 patients were collected in 2020 and classified into four levels of severity ranging from mild symptoms to severe ventilated cases. These samples were investigated using a combination of quantitative Nuclear Magnetic Resonance (NMR) spectroscopy and Mass Spectrometry (MS) platforms to give broad lipoprotein, lipidomic and amino acid, tryptophan-kynurenine pathway, and biogenic amine pathway coverage. All platforms revealed highly significant differences in metabolite patterns between patients and controls (n = 89) that had been collected prior to the COVID-19 pandemic. The total number of significant metabolites increased with severity with 344 out of the 1034 quantitative variables being common to all severity classes. Metabolic signatures showed a continuum of changes across the respiratory severity levels with the most significant and extensive changes being in the most severely affected patients. Even mildly affected respiratory patients showed multiple highly significant abnormal biochemical signatures reflecting serious metabolic deficiencies of the type observed in Post-acute COVID-19 syndrome patients. The most severe respiratory patients had a high mortality (56.1%) and we found that we could predict mortality in this patient sub-group with high accuracy in some cases up to 61 days prior to death, based on a separate metabolic model, which highlighted a different set of metabolites to those defining the basic disease. Specifically, hexosylceramides (HCER 16:0, HCER 20:0, HCER 24:1, HCER 26:0, HCER 26:1) were markedly elevated in the non-surviving patient group (Cliff's delta 0.91-0.95) and two phosphoethanolamines (PE.O 18:0/18:1, Cliff's delta = -0.98 and PE.P 16:0/18:1, Cliff's delta = -0.93) were markedly lower in the non-survivors. These results indicate that patient morbidity to mortality trajectories is determined relatively soon after infection, opening the opportunity to select more intensive therapeutic interventions to these "high risk" patients in the early disease stages.
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Affiliation(s)
- Samantha Lodge
- Australian National Phenome Center, Health Futures Institute, Murdoch University, Harry Perkins Building, Perth, WA 6150, Australia; (S.L.); (N.G.L.); (N.G.); (R.M.); (P.N.); (L.W.); (S.-H.B.); (E.H.)
- Center for Computational and Systems Medicine, Health Futures Institute, Murdoch University, Harry Perkins Building, Perth, WA 6150, Australia
| | - Nathan G. Lawler
- Australian National Phenome Center, Health Futures Institute, Murdoch University, Harry Perkins Building, Perth, WA 6150, Australia; (S.L.); (N.G.L.); (N.G.); (R.M.); (P.N.); (L.W.); (S.-H.B.); (E.H.)
- Center for Computational and Systems Medicine, Health Futures Institute, Murdoch University, Harry Perkins Building, Perth, WA 6150, Australia
| | - Nicola Gray
- Australian National Phenome Center, Health Futures Institute, Murdoch University, Harry Perkins Building, Perth, WA 6150, Australia; (S.L.); (N.G.L.); (N.G.); (R.M.); (P.N.); (L.W.); (S.-H.B.); (E.H.)
- Center for Computational and Systems Medicine, Health Futures Institute, Murdoch University, Harry Perkins Building, Perth, WA 6150, Australia
| | - Reika Masuda
- Australian National Phenome Center, Health Futures Institute, Murdoch University, Harry Perkins Building, Perth, WA 6150, Australia; (S.L.); (N.G.L.); (N.G.); (R.M.); (P.N.); (L.W.); (S.-H.B.); (E.H.)
| | - Philipp Nitschke
- Australian National Phenome Center, Health Futures Institute, Murdoch University, Harry Perkins Building, Perth, WA 6150, Australia; (S.L.); (N.G.L.); (N.G.); (R.M.); (P.N.); (L.W.); (S.-H.B.); (E.H.)
| | - Luke Whiley
- Australian National Phenome Center, Health Futures Institute, Murdoch University, Harry Perkins Building, Perth, WA 6150, Australia; (S.L.); (N.G.L.); (N.G.); (R.M.); (P.N.); (L.W.); (S.-H.B.); (E.H.)
- Center for Computational and Systems Medicine, Health Futures Institute, Murdoch University, Harry Perkins Building, Perth, WA 6150, Australia
| | - Sze-How Bong
- Australian National Phenome Center, Health Futures Institute, Murdoch University, Harry Perkins Building, Perth, WA 6150, Australia; (S.L.); (N.G.L.); (N.G.); (R.M.); (P.N.); (L.W.); (S.-H.B.); (E.H.)
| | - Bu B. Yeap
- Medical School, University of Western Australia, Perth, WA 6150, Australia; (B.B.Y.); (G.D.)
- Department of Endocrinology and Diabetes, Fiona Stanley Hospital, Perth, WA 6150, Australia
| | - Girish Dwivedi
- Medical School, University of Western Australia, Perth, WA 6150, Australia; (B.B.Y.); (G.D.)
- Department of Cardiology, Fiona Stanley Hospital, Perth, WA 6150, Australia
| | | | | | - Rubén Gil-Redondo
- Precision Medicine and Metabolism Laboratory, CIC bioGUNE, Parque Tecnológico de Bizkaia, Bld. 800, 48160 Derio, Spain; (R.G.-R.); (N.E.); (O.M.)
| | - Nieves Embade
- Precision Medicine and Metabolism Laboratory, CIC bioGUNE, Parque Tecnológico de Bizkaia, Bld. 800, 48160 Derio, Spain; (R.G.-R.); (N.E.); (O.M.)
| | - Oscar Millet
- Precision Medicine and Metabolism Laboratory, CIC bioGUNE, Parque Tecnológico de Bizkaia, Bld. 800, 48160 Derio, Spain; (R.G.-R.); (N.E.); (O.M.)
| | - Elaine Holmes
- Australian National Phenome Center, Health Futures Institute, Murdoch University, Harry Perkins Building, Perth, WA 6150, Australia; (S.L.); (N.G.L.); (N.G.); (R.M.); (P.N.); (L.W.); (S.-H.B.); (E.H.)
- Center for Computational and Systems Medicine, Health Futures Institute, Murdoch University, Harry Perkins Building, Perth, WA 6150, Australia
- Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, Sir Alexander Fleming Building, South Kensington, London SW7 2AZ, UK
| | - Julien Wist
- Australian National Phenome Center, Health Futures Institute, Murdoch University, Harry Perkins Building, Perth, WA 6150, Australia; (S.L.); (N.G.L.); (N.G.); (R.M.); (P.N.); (L.W.); (S.-H.B.); (E.H.)
- Center for Computational and Systems Medicine, Health Futures Institute, Murdoch University, Harry Perkins Building, Perth, WA 6150, Australia
- Chemistry Department, Universidad del Valle, Cali 76001, Colombia
| | - Jeremy K. Nicholson
- Australian National Phenome Center, Health Futures Institute, Murdoch University, Harry Perkins Building, Perth, WA 6150, Australia; (S.L.); (N.G.L.); (N.G.); (R.M.); (P.N.); (L.W.); (S.-H.B.); (E.H.)
- Center for Computational and Systems Medicine, Health Futures Institute, Murdoch University, Harry Perkins Building, Perth, WA 6150, Australia
- Institute of Global Health Innovation, Faculty of Medicine, Imperial College London, Faculty Building, South Kensington Campus, London SW7 2NA, UK
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Midttun Ø, Ulvik A, Meyer K, Zahed H, Giles GG, Manjer J, Sandsveden M, Langhammer A, Sørgjerd EP, Behndig AF, Johansson M, Freedman ND, Huang WY, Chen C, Prentice R, Stevens VL, Wang Y, Le Marchand L, Weinstein SJ, Cai Q, Arslan AA, Chen Y, Shu XO, Zheng W, Yuan JM, Koh WP, Visvanathan K, Sesso HD, Zhang X, Gaziano JM, Fanidi A, Robbins HA, Brennan P, Johansson M, Ueland PM. A cross-sectional study of inflammatory markers as determinants of circulating kynurenines in the Lung Cancer Cohort Consortium. Sci Rep 2023; 13:1011. [PMID: 36653422 PMCID: PMC9849351 DOI: 10.1038/s41598-023-28135-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Accepted: 01/13/2023] [Indexed: 01/19/2023] Open
Abstract
Circulating concentrations of metabolites (collectively called kynurenines) in the kynurenine pathway of tryptophan metabolism increase during inflammation, particularly in response to interferon-gamma (IFN-γ). Neopterin and the kynurenine/tryptophan ratio (KTR) are IFN-γ induced inflammatory markers, and together with C-reactive protein (CRP) and kynurenines they are associated with various diseases, but comprehensive data on the strength of associations of inflammatory markers with circulating concentrations of kynurenines are lacking. We measured circulating concentrations of neopterin, CRP, tryptophan and seven kynurenines in 5314 controls from 20 cohorts in the Lung Cancer Cohort Consortium (LC3). The associations of neopterin, KTR and CRP with kynurenines were investigated using regression models. In mixed models, one standard deviation (SD) higher KTR was associated with a 0.46 SD higher quinolinic acid (QA), and 0.31 SD higher 3-hydroxykynurenine (HK). One SD higher neopterin was associated with 0.48, 0.44, 0.36 and 0.28 SD higher KTR, QA, kynurenine and HK, respectively. KTR and neopterin respectively explained 24.1% and 16.7% of the variation in QA, and 11.4% and 7.5% of HK. CRP was only weakly associated with kynurenines in regression models. In summary, QA was the metabolite that was most strongly associated with the inflammatory markers. In general, the inflammatory markers were most strongly related to metabolites located along the tryptophan-NAD axis, which may support suggestions of increased production of NAD from tryptophan during inflammation.
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Affiliation(s)
- Øivind Midttun
- Bevital AS, Laboratory Building, Jonas Lies Veg 87, 5021, Bergen, Norway.
| | - Arve Ulvik
- Bevital AS, Laboratory Building, Jonas Lies Veg 87, 5021, Bergen, Norway
| | - Klaus Meyer
- Bevital AS, Laboratory Building, Jonas Lies Veg 87, 5021, Bergen, Norway
| | - Hana Zahed
- Genomic Epidemiology Branch, International Agency for Research on Cancer, Lyon, France
| | - Graham G Giles
- Cancer Epidemiology Division, Cancer Council Victoria, Melbourne, Australia
- Centre for Epidemiology and Biostatistics, School of Population and Global Health, The University of Melbourne, Melbourne, Australia
- Precision Medicine, School of Clinical Sciences at Monash Health, Monash University, Melbourne, Australia
| | - Jonas Manjer
- Department of Surgery, Skane University Hospital, Malmö, Sweden
- Lund University, Malmö, Sweden
| | - Malte Sandsveden
- Department of Clinical Sciences Malmo, Lund University, Malmö, Sweden
| | - Arnulf Langhammer
- Department of Public Health and Nursing, Hunt Research Centre, Norwegian University of Science and Technology, Levanger, Norway
- Levanger Hospital, Nord-Trøndelag Hospital Trust, Levanger, Norway
| | - Elin Pettersen Sørgjerd
- Department of Public Health and Nursing, Hunt Research Centre, Norwegian University of Science and Technology, Levanger, Norway
- Department of Endocrinology, St. Olavs Hospital, Trondheim University Hospital, Levanger, Norway
| | - Annelie F Behndig
- Department of Public Health and Clinical Medicine, Umea University, Umeå, Sweden
| | - Mikael Johansson
- Department of Radiation Sciences, Oncology, Umea University, Umeå, Sweden
| | - Neal D Freedman
- Metabolic Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD, USA
| | - Wen-Yi Huang
- Metabolic Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD, USA
| | - Chu Chen
- Public Health Sciences Division, Fred Hutchinson Cancer Center, Seattle, USA
| | - Ross Prentice
- Public Health Sciences Division, Fred Hutchinson Cancer Center, Seattle, USA
| | | | - Ying Wang
- American Cancer Society, Atlanta, USA
| | - Loïc Le Marchand
- University of Hawai'i Cancer Center, University of Hawai'i at Mānoa, Honolulu, USA
| | - Stephanie J Weinstein
- Metabolic Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD, USA
| | - Qiuyin Cai
- Vanderbilt University Medical Center, Nashville, USA
| | - Alan A Arslan
- Department of Obstetrics and Gynecology, NYU Langone Health, New York, NY, USA
- Department of Population Health, NYU Langone Health, New York, NY, USA
- Perlmutter Comprehensive Cancer Center, NYU Langone Health, New York, NY, USA
| | - Yu Chen
- Department of Population Health, NYU Langone Health, New York, NY, USA
- Perlmutter Comprehensive Cancer Center, NYU Langone Health, New York, NY, USA
| | - Xiao-Ou Shu
- Department of Population Health, NYU Langone Health, New York, NY, USA
| | - Wei Zheng
- Department of Population Health, NYU Langone Health, New York, NY, USA
| | - Jian-Min Yuan
- University of Pittsburgh and UPMC Hillman Cancer Center, Pittsburgh, USA
| | - Woon-Puay Koh
- Healthy Longevity Translational Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Kala Visvanathan
- Johns Hopkins Institute for Clinical and Translational Research, Baltimore, USA
| | - Howard D Sesso
- Brigham and Women's Hospital, Harvard Medical School, Boston, USA
- Harvard T.H. Chan School of Public Health, Boston, USA
| | - Xuehong Zhang
- Brigham and Women's Hospital, Harvard Medical School, Boston, USA
- Harvard T.H. Chan School of Public Health, Boston, USA
| | - J Michael Gaziano
- Brigham and Women's Hospital, Boston, USA
- VA Boston Healthcare System, Boston, MA, USA
| | | | - Hilary A Robbins
- Genomic Epidemiology Branch, International Agency for Research on Cancer, Lyon, France
| | - Paul Brennan
- Genomic Epidemiology Branch, International Agency for Research on Cancer, Lyon, France
| | - Mattias Johansson
- Genomic Epidemiology Branch, International Agency for Research on Cancer, Lyon, France
| | - Per M Ueland
- Bevital AS, Laboratory Building, Jonas Lies Veg 87, 5021, Bergen, Norway
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The Combined Escherichia coli Nissle 1917 and Tryptophan Treatment Modulates Immune and Metabolome Responses to Human Rotavirus Infection in a Human Infant Fecal Microbiota-Transplanted Malnourished Gnotobiotic Pig Model. mSphere 2022; 7:e0027022. [PMID: 36073800 PMCID: PMC9599269 DOI: 10.1128/msphere.00270-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human rotavirus (HRV) is a major cause of childhood diarrhea in developing countries where widespread malnutrition contributes to the decreased oral vaccine efficacy and increased prevalence of other enteric infections, which are major concerns for global health. Neonatal gnotobiotic (Gn) piglets closely resemble human infants in their anatomy, physiology, and outbred status, providing a unique model to investigate malnutrition, supplementations, and HRV infection. To understand the molecular signatures associated with immune enhancement and reduced diarrheal severity by Escherichia coli Nissle 1917 (EcN) and tryptophan (TRP), immunological responses and global nontargeted metabolomics and lipidomics approaches were investigated on the plasma and fecal contents of malnourished pigs transplanted with human infant fecal microbiota and infected with virulent (Vir) HRV. Overall, EcN + TRP combined (rather than individual supplement action) promoted greater and balanced immunoregulatory/immunostimulatory responses associated with greater protection against HRV infection and disease in malnourished humanized piglets. Moreover, EcN + TRP treatment upregulated the production of several metabolites with immunoregulatory/immunostimulatory properties: amino acids (N-acetylserotonin, methylacetoacetyl-CoA), lipids (gamma-butyrobetaine, eicosanoids, cholesterol-sulfate, sphinganine/phytosphingosine, leukotriene), organic compound (biliverdin), benzenoids (gentisic acid, aminobenzoic acid), and nucleotides (hypoxathine/inosine/xanthine, cytidine-5'-monophosphate). Additionally, the levels of several proinflammatory metabolites of organic compounds (adenosylhomocysteine, phenylacetylglycine, urobilinogen/coproporphyrinogen) and amino acid (phenylalanine) were reduced following EcN + TRP treatment. These results suggest that the EcN + TRP effects on reducing HRV diarrhea in neonatal Gn pigs were at least in part due to altered metabolites, those involved in lipid, amino acid, benzenoids, organic compounds, and nucleotide metabolism. Identification of these important mechanisms of EcN/TRP prevention of HRV diarrhea provides novel targets for therapeutics development. IMPORTANCE Human rotavirus (HRV) is the most common cause of viral gastroenteritis in children, especially in developing countries, where the efficacy of oral HRV vaccines is reduced. Escherichia coli Nissle 1917 (EcN) is used to treat enteric infections and ulcerative colitis while tryptophan (TRP) is a biomarker of malnutrition, and its supplementation can alleviate intestinal inflammation and normalize intestinal microbiota in malnourished hosts. Supplementation of EcN + TRP to malnourished humanized gnotobiotic piglets enhanced immune responses and resulted in greater protection against HRV infection and diarrhea. Moreover, EcN + TRP supplementation increased the levels of immunoregulatory/immunostimulatory metabolites while decreasing the production of proinflammatory metabolites in plasma and fecal samples. Profiling of immunoregulatory and proinflammatory biomarkers associated with HRV perturbations will aid in the identification of treatments against HRV and other enteric diseases in malnourished children.
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Ren Z, Xu Y, Li T, Sun W, Tang Z, Wang Y, Zhou K, Li J, Ding Q, Liang K, Wu L, Yin Y, Sun Z. NAD+ and its possible role in gut microbiota: Insights on the mechanisms by which gut microbes influence host metabolism. ANIMAL NUTRITION 2022; 10:360-371. [PMID: 35949199 PMCID: PMC9356074 DOI: 10.1016/j.aninu.2022.06.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 03/01/2022] [Accepted: 06/15/2022] [Indexed: 11/26/2022]
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8
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Wang Y, Pleasure D, Deng W, Guo F. Therapeutic Potentials of Poly (ADP-Ribose) Polymerase 1 (PARP1) Inhibition in Multiple Sclerosis and Animal Models: Concept Revisiting. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2102853. [PMID: 34935305 PMCID: PMC8844485 DOI: 10.1002/advs.202102853] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 10/12/2021] [Indexed: 05/05/2023]
Abstract
Poly (ADP-ribose) polymerase 1 (PARP1) plays a fundamental role in DNA repair and gene expression. Excessive PARP1 hyperactivation, however, has been associated with cell death. PARP1 and/or its activity are dysregulated in the immune and central nervous system of multiple sclerosis (MS) patients and animal models. Pharmacological PARP1 inhibition is shown to be protective against immune activation and disease severity in MS animal models while genetic PARP1 deficiency studies reported discrepant results. The inconsistency suggests that the function of PARP1 and PARP1-mediated PARylation may be complex and context-dependent. The article reviews PARP1 functions, discusses experimental findings and possible interpretations of PARP1 in inflammation, neuronal/axonal degeneration, and oligodendrogliopathy, three major pathological components cooperatively determining MS disease course and neurological progression, and points out future research directions. Cell type specific PARP1 manipulations are necessary for revisiting the role of PARP1 in the three pathological components prior to moving PARP1 inhibition into clinical trials for MS therapy.
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Affiliation(s)
- Yan Wang
- Department of NeurologySchool of MedicineUniversity of CaliforniaDavisCA95817USA
- Institute for Pediatric Regenerative MedicineUC Davis School of Medicine/Shriners Hospitals for ChildrenSacramentoCAUSA
| | - David Pleasure
- Department of NeurologySchool of MedicineUniversity of CaliforniaDavisCA95817USA
- Institute for Pediatric Regenerative MedicineUC Davis School of Medicine/Shriners Hospitals for ChildrenSacramentoCAUSA
| | - Wenbin Deng
- School of Pharmaceutical Sciences (Shenzhen)Sun Yat‐sen UniversityGuangzhou510006China
| | - Fuzheng Guo
- Department of NeurologySchool of MedicineUniversity of CaliforniaDavisCA95817USA
- Institute for Pediatric Regenerative MedicineUC Davis School of Medicine/Shriners Hospitals for ChildrenSacramentoCAUSA
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9
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Kim CK, Sachdev PS, Braidy N. Recent Neurotherapeutic Strategies to Promote Healthy Brain Aging: Are we there yet? Aging Dis 2022; 13:175-214. [PMID: 35111369 PMCID: PMC8782556 DOI: 10.14336/ad.2021.0705] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 07/05/2021] [Indexed: 12/21/2022] Open
Abstract
Owing to the global exponential increase in population ageing, there is an urgent unmet need to develop reliable strategies to slow down and delay the ageing process. Age-related neurodegenerative diseases are among the main causes of morbidity and mortality in our contemporary society and represent a major socio-economic burden. There are several controversial factors that are thought to play a causal role in brain ageing which are continuously being examined in experimental models. Among them are oxidative stress and brain inflammation which are empirical to brain ageing. Although some candidate drugs have been developed which reduce the ageing phenotype, their clinical translation is limited. There are several strategies currently in development to improve brain ageing. These include strategies such as caloric restriction, ketogenic diet, promotion of cellular nicotinamide adenine dinucleotide (NAD+) levels, removal of senescent cells, 'young blood' transfusions, enhancement of adult neurogenesis, stem cell therapy, vascular risk reduction, and non-pharmacological lifestyle strategies. Several studies have shown that these strategies can not only improve brain ageing by attenuating age-related neurodegenerative disease mechanisms, but also maintain cognitive function in a variety of pre-clinical experimental murine models. However, clinical evidence is limited and many of these strategies are awaiting findings from large-scale clinical trials which are nascent in the current literature. Further studies are needed to determine their long-term efficacy and lack of adverse effects in various tissues and organs to gain a greater understanding of their potential beneficial effects on brain ageing and health span in humans.
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Affiliation(s)
- Chul-Kyu Kim
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia
| | - Perminder S Sachdev
- Neuropsychiatric Institute, Euroa Centre, Prince of Wales Hospital, Sydney, Australia
| | - Nady Braidy
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia
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The effect of 2-amino-3-carboxymuconate-6-semialdehyde decarboxylase gene overexpression in the kynurenine pathway on the expression levels of indoleamine 2,3-dioxygenase 1 and interferon-γ in inflammatory conditions: an in vitro study. Mol Biol Rep 2021; 49:1103-1111. [PMID: 34775574 DOI: 10.1007/s11033-021-06935-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 11/05/2021] [Indexed: 10/19/2022]
Abstract
BACKGROUND The kynurenine pathway (KP) can be involved in the pathogenesis of neurodegenerative diseases and excessive neurotoxic metabolite production. This study aimed to evaluate the effects of overexpression of murine 2-amino-3-carboxymuconate-6-semialdehyde decarboxylase (Acmsd) gene in inflammatory conditions in RAW 264.7 cell line to present more information about the effect of this gene on inflammatory conditions and the KP cycle. METHODS AND RESULTS The coding sequence of the Acmsd gene was cloned into pCMV6-AC-IRES-GFP expression vector with a green fluorescent protein (GFP) marker. To simulate inflammatory conditions, RAW 264.7 macrophage cells were stimulated by Lipopolysaccharide (LPS) 24 h before transfection, and transfected by Polyethyleneimine (PEI) with constructed plasmids expressing the Acmsd gene. The effect of Acmsd gene expression level on murine Interferon-gamma (Ifn-γ) and murine Indoleamine 2,3-dioxygenase 1 (Ido1) gene expression level was investigated by Real-Time PCR. According to the results of this study, good transfection efficiency was observed 72 h after transfection, and Acmsd expression level increased 29-fold (P < 0.001) in transfected LPS-stimulated cells compared to the control group (LPS-stimulated cells that were not transfected). Additionally, increased Acmsd expression level significantly down-regulated Ifn-γ (P < 0.001) and Ido1 (P < 0.01) expression level in transfected LPS-stimulated cells compared to LPS-stimulated cells. CONCLUSIONS Acmsd gene overexpression in inflammatory conditions can reduce the expression levels of the Ido1 gene, and its regulator, Ifn-γ. Consequently, it may be considered as a novel regulatory factor in the KP balance.
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11
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Krupa A, Kowalska I. The Kynurenine Pathway-New Linkage between Innate and Adaptive Immunity in Autoimmune Endocrinopathies. Int J Mol Sci 2021; 22:9879. [PMID: 34576041 PMCID: PMC8469440 DOI: 10.3390/ijms22189879] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 09/09/2021] [Accepted: 09/10/2021] [Indexed: 12/18/2022] Open
Abstract
The kynurenine pathway (KP) is highly regulated in the immune system, where it promotes immunosuppression in response to infection or inflammation. Indoleamine 2,3-dioxygenase 1 (IDO1), the main enzyme of KP, has a broad spectrum of activity on immune cells regulation, controlling the balance between stimulation and suppression of the immune system at sites of local inflammation, relevant to a wide range of autoimmune and inflammatory diseases. Various autoimmune diseases, among them endocrinopathies, have been identified to date, but despite significant progress in their diagnosis and treatment, they are still associated with significant complications, morbidity, and mortality. The precise cellular and molecular mechanisms leading to the onset and development of autoimmune disease remain poorly clarified so far. In breaking of tolerance, the cells of the innate immunity provide a decisive microenvironment that regulates immune cells' differentiation, leading to activation of adaptive immunity. The current review provided a comprehensive presentation of the known role of IDO1 and KP activation in the regulation of the innate and adaptive arms of the immune system. Significant attention has been paid to the immunoregulatory role of IDO1 in the most prevalent, organ-specific autoimmune endocrinopathies-type 1 diabetes mellitus (T1DM) and autoimmune thyroiditis.
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Affiliation(s)
- Anna Krupa
- Department of Internal Medicine and Metabolic Diseases, Medical University of Bialystok, M. Sklodowskiej-Curie 24A, 15-276 Bialystok, Poland
| | - Irina Kowalska
- Department of Internal Medicine and Metabolic Diseases, Medical University of Bialystok, M. Sklodowskiej-Curie 24A, 15-276 Bialystok, Poland
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12
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Joisten N, Ruas JL, Braidy N, Guillemin GJ, Zimmer P. The kynurenine pathway in chronic diseases: a compensatory mechanism or a driving force? Trends Mol Med 2021; 27:946-954. [PMID: 34373202 DOI: 10.1016/j.molmed.2021.07.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 07/05/2021] [Accepted: 07/09/2021] [Indexed: 12/14/2022]
Abstract
The kynurenine (KYN) pathway (KP) of tryptophan (TRP) metabolism is dysregulated in inflammation-driven pathologies including oncological and brain diseases [e.g., multiple sclerosis (MS), depression] and thus is a promising therapeutic target. Both pathological and compensatory mechanisms underlie disease-associated KP activation. There is growing evidence for bioenergetic roles of certain KP metabolites such as kynurenic acid (KA), or quinolinic acid (QA) as an NAD+ precursor, which may explain its frequently observed 'pathological' overactivation. Disease- and tissue-specific aspects, negative feedback on inflammatory signals, and the balance of downstream metabolites are likely to be decisive factors in the interpretation of an imbalanced KP. Therapeutic strategies should consider the compensatory actions and bioenergetic roles of KP metabolites to successfully design future theragnostic approaches aimed at attenuating disease progression.
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Affiliation(s)
- Niklas Joisten
- Division of Performance and Health (Sports Medicine), Institute for Sport and Sport Science, Technical University Dortmund, Dortmund, Germany.
| | - Jorge L Ruas
- Molecular and Cellular Exercise Physiology, Department of Physiology and Pharmacology, Biomedicum, Karolinska Institutet, Stockholm, Sweden
| | - Nady Braidy
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, NSW, Australia
| | - Gilles J Guillemin
- Neuroinflammation Group, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, NSW, Australia
| | - Philipp Zimmer
- Division of Performance and Health (Sports Medicine), Institute for Sport and Sport Science, Technical University Dortmund, Dortmund, Germany
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13
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Cho SJ, Hong KS, Schenck E, Lee S, Harris R, Yang J, Choi AMK, Stout-Delgado H. Decreased IDO1-dependent tryptophan metabolism in aged lung during influenza. Eur Respir J 2021; 57:13993003.00443-2020. [PMID: 33243840 DOI: 10.1183/13993003.00443-2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 11/08/2020] [Indexed: 11/05/2022]
Abstract
Influenza epidemics remain a leading cause of morbidity and mortality worldwide. In the current study, we investigated the impact of chronological ageing on tryptophan metabolism in response to influenza infection.Examination of metabolites present in plasma collected from critically ill patients identified tryptophan metabolism as an important metabolic pathway utilised specifically in response to influenza. Using a murine model of influenza infection to further these findings illustrated that there was decreased production of kynurenine in aged lung in an indoleamine-pyrrole 2,3-dioxygenase-dependent manner that was associated with increased inflammatory and diminished regulatory responses. Specifically, within the first 7 days of influenza, there was a decrease in kynurenine pathway mediated metabolism of tryptophan, which resulted in a subsequent increase in ketone body catabolism in aged alveolar macrophages. Treatment of aged mice with mitoquinol, a mitochondrial targeted antioxidant, improved mitochondrial function and restored tryptophan metabolism.Taken together, our data provide additional evidence as to why older persons are more susceptible to influenza and suggest a possible therapeutic to improve immunometabolic responses in this population.
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Affiliation(s)
- Soo Jung Cho
- Dept of Medicine, Pulmonary and Critical Care, Weill Cornell Medicine, New York, NY, USA
| | - Kyung Sook Hong
- Dept of Medicine, Pulmonary and Critical Care, Weill Cornell Medicine, New York, NY, USA
| | - Edward Schenck
- Dept of Medicine, Pulmonary and Critical Care, Weill Cornell Medicine, New York, NY, USA
| | - Stefi Lee
- Dept of Medicine, Pulmonary and Critical Care, Weill Cornell Medicine, New York, NY, USA
| | - Rebecca Harris
- Dept of Medicine, Pulmonary and Critical Care, Weill Cornell Medicine, New York, NY, USA
| | - Jianjun Yang
- Dept of Medicine, Pulmonary and Critical Care, Weill Cornell Medicine, New York, NY, USA
| | - Augustine M K Choi
- Dept of Medicine, Pulmonary and Critical Care, Weill Cornell Medicine, New York, NY, USA
| | - Heather Stout-Delgado
- Dept of Medicine, Pulmonary and Critical Care, Weill Cornell Medicine, New York, NY, USA
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Biernacki T, Sandi D, Bencsik K, Vécsei L. Kynurenines in the Pathogenesis of Multiple Sclerosis: Therapeutic Perspectives. Cells 2020; 9:cells9061564. [PMID: 32604956 PMCID: PMC7349747 DOI: 10.3390/cells9061564] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 06/22/2020] [Accepted: 06/23/2020] [Indexed: 12/11/2022] Open
Abstract
Over the past years, an increasing amount of evidence has emerged in support of the kynurenine pathway’s (KP) pivotal role in the pathogenesis of several neurodegenerative, psychiatric, vascular and autoimmune diseases. Different neuroactive metabolites of the KP are known to exert opposite effects on neurons, some being neuroprotective (e.g., picolinic acid, kynurenic acid, and the cofactor nicotinamide adenine dinucleotide), while others are toxic to neurons (e.g., 3-hydroxykynurenine, quinolinic acid). Not only the alterations in the levels of the metabolites but also disturbances in their ratio (quinolinic acid/kynurenic acid) have been reported in several diseases. In addition to the metabolites, the enzymes participating in the KP have been unearthed to be involved in modulation of the immune system, the energetic upkeep of neurons and have been shown to influence redox processes and inflammatory cascades, revealing a sophisticated, intertwined system. This review considers various methods through which enzymes and metabolites of the kynurenine pathway influence the immune system, the roles they play in the pathogenesis of neuroinflammatory diseases based on current evidence with a focus on their involvement in multiple sclerosis, as well as therapeutic approaches.
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Affiliation(s)
- Tamás Biernacki
- Department of Neurology, Faculty of General Medicine, Albert Szent-Györgyi Clinical Centre, University of Szeged, H-6725 Szeged, Hungary; (T.B.); (D.S.); (K.B.)
| | - Dániel Sandi
- Department of Neurology, Faculty of General Medicine, Albert Szent-Györgyi Clinical Centre, University of Szeged, H-6725 Szeged, Hungary; (T.B.); (D.S.); (K.B.)
| | - Krisztina Bencsik
- Department of Neurology, Faculty of General Medicine, Albert Szent-Györgyi Clinical Centre, University of Szeged, H-6725 Szeged, Hungary; (T.B.); (D.S.); (K.B.)
| | - László Vécsei
- Department of Neurology, Faculty of General Medicine, Albert Szent-Györgyi Clinical Centre, University of Szeged, H-6725 Szeged, Hungary; (T.B.); (D.S.); (K.B.)
- MTA—SZTE Neuroscience Research Group, H-6725 Szeged, Hungary
- Interdisciplinary Excellence Center, University of Szeged, H-6720 Szeged, Hungary
- Correspondence: ; Tel.: +36-62-545-356; Fax: +36-62-545-597
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15
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Moffett JR, Arun P, Puthillathu N, Vengilote R, Ives JA, Badawy AAB, Namboodiri AM. Quinolinate as a Marker for Kynurenine Metabolite Formation and the Unresolved Question of NAD + Synthesis During Inflammation and Infection. Front Immunol 2020; 11:31. [PMID: 32153556 PMCID: PMC7047773 DOI: 10.3389/fimmu.2020.00031] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 01/08/2020] [Indexed: 12/26/2022] Open
Abstract
Quinolinate (Quin) is a classic example of a biochemical double-edged sword, acting as both essential metabolite and potent neurotoxin. Quin is an important metabolite in the kynurenine pathway of tryptophan catabolism leading to the de novo synthesis of nicotinamide adenine dinucleotide (NAD+). As a precursor for NAD+, Quin can direct a portion of tryptophan catabolism toward replenishing cellular NAD+ levels in response to inflammation and infection. Intracellular Quin levels increase dramatically in response to immune stimulation [e.g., lipopolysaccharide (LPS) or pokeweed mitogen (PWM)] in macrophages, microglia, dendritic cells, and other cells of the immune system. NAD+ serves numerous functions including energy production, the poly ADP ribose polymerization (PARP) reaction involved in DNA repair, and the activity of various enzymes such as the NAD+-dependent deacetylases known as sirtuins. We used highly specific antibodies to protein-coupled Quin to delineate cells that accumulate Quin as a key aspect of the response to immune stimulation and infection. Here, we describe Quin staining in the brain, spleen, and liver after LPS administration to the brain or systemic PWM administration. Quin expression was strong in immune cells in the periphery after both treatments, whereas very limited Quin expression was observed in the brain even after direct LPS injection. Immunoreactive cells exhibited diverse morphology ranging from foam cells to cells with membrane extensions related to cell motility. We also examined protein expression changes in the spleen after kynurenine administration. Acute (8 h) and prolonged (48 h) kynurenine administration led to significant changes in protein expression in the spleen, including multiple changes involved with cytoskeletal rearrangements associated with cell motility. Kynurenine administration resulted in several expression level changes in proteins associated with heat shock protein 90 (HSP90), a chaperone for the aryl-hydrocarbon receptor (AHR), which is the primary kynurenine metabolite receptor. We propose that cells with high levels of Quin are those that are currently releasing kynurenine pathway metabolites as well as accumulating Quin for sustained NAD+ synthesis from tryptophan. Further, we propose that the kynurenine pathway may be linked to the regulation of cell motility in immune and cancer cells.
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Affiliation(s)
- John R. Moffett
- Departments of Anatomy, Physiology and Genetics and Neuroscience Program, Uniformed Services University Medical School, Bethesda, MD, United States
| | - Peethambaran Arun
- Departments of Anatomy, Physiology and Genetics and Neuroscience Program, Uniformed Services University Medical School, Bethesda, MD, United States
| | - Narayanan Puthillathu
- Departments of Anatomy, Physiology and Genetics and Neuroscience Program, Uniformed Services University Medical School, Bethesda, MD, United States
| | - Ranjini Vengilote
- Departments of Anatomy, Physiology and Genetics and Neuroscience Program, Uniformed Services University Medical School, Bethesda, MD, United States
| | - John A. Ives
- The Center for Brain, Mind, and Healing, Samueli Institute, Alexandria, VA, United States
| | | | - Aryan M. Namboodiri
- Departments of Anatomy, Physiology and Genetics and Neuroscience Program, Uniformed Services University Medical School, Bethesda, MD, United States
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16
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Braidy N, Liu Y. NAD+ therapy in age-related degenerative disorders: A benefit/risk analysis. Exp Gerontol 2020; 132:110831. [PMID: 31917996 DOI: 10.1016/j.exger.2020.110831] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/23/2019] [Accepted: 01/02/2020] [Indexed: 02/06/2023]
Abstract
Nicotinamide adenine dinucleotide (NAD+) is an essential pyridine nucleotide that is present in all living cells. NAD+ acts as an important cofactor and substrate for a multitude of biological processes including energy production, DNA repair, gene expression, calcium-dependent secondary messenger signalling and immunoregulatory roles. The de novo synthesis of NAD+ is primarily dependent on the kynurenine pathway (KP), although NAD+ can also be recycled from nicotinic acid (NA), nicotinamide (NAM) and nicotinamide riboside (NR). NAD+ levels have been reported to decline during ageing and age-related diseases. Recent studies have shown that raising intracellular NAD+ levels represents a promising therapeutic strategy for age-associated degenerative diseases in general and to extend lifespan in small animal models. A systematic review of the literature available on Medline, Embase and Pubmed was undertaken to evaluate the potential health and/or longevity benefits due to increasing NAD+ levels. A total of 1545 articles were identified and 147 articles (113 preclinical and 34 clinical) met criteria for inclusion. Most studies indicated that the NAD+ precursors NAM, NR, nicotinamide mononucleotide (NMN), and to a lesser extent NAD+ and NADH had a favourable outcome on several age-related disorders associated with the accumulation of chronic oxidative stress, inflammation and impaired mitochondrial function. While these compounds presented with a limited acute toxicity profile, evidence is still quite limited and long-term human clinical trials are still nascent in the current literature. Potential risks in raising NAD+ levels in various clinical disorders using NAD+ precursors include the accumulation of putative toxic metabolites, tumorigenesis and promotion of cellular senescence. Therefore, NAD+ metabolism represents a promising target and further studies are needed to recapitulate the preclinical benefits in human clinical trials.
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Affiliation(s)
- Nady Braidy
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia.
| | - Yue Liu
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia
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Williams AC, Hill LJ. Nicotinamide and Demographic and Disease transitions: Moderation is Best. Int J Tryptophan Res 2019; 12:1178646919855940. [PMID: 31320805 PMCID: PMC6610439 DOI: 10.1177/1178646919855940] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 05/03/2019] [Indexed: 12/13/2022] Open
Abstract
Good health and rapid progress depend on an optimal dose of nicotinamide. Too little meat triggers the neurodegenerative condition pellagra and tolerance of symbionts such as tuberculosis (TB), risking dysbioses and impaired resistance to acute infections. Nicotinamide deficiency is an overlooked diagnosis in poor cereal-dependant economies masquerading as 'environmental enteropathy' or physical and cognitive stunting. Too much meat (and supplements) may precipitate immune intolerance and autoimmune and allergic disease, with relative infertility and longevity, via the tryptophan-nicotinamide pathway. This switch favours a dearth of regulatory T (Treg) and an excess of T helper cells. High nicotinamide intake is implicated in cancer and Parkinson's disease. Pro-fertility genes, evolved to counteract high-nicotinamide-induced infertility, may now be risk factors for degenerative disease. Moderation of the dose of nicotinamide could prevent some common diseases and personalised doses at times of stress or, depending on genetic background or age, may treat some other conditions.
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Affiliation(s)
- Adrian C Williams
- Department of Neurology, University
Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Lisa J Hill
- School of Biomedical Sciences, Institute
of Clinical Sciences, University of Birmingham, Birmingham, UK
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18
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Braidy N, Berg J, Clement J, Khorshidi F, Poljak A, Jayasena T, Grant R, Sachdev P. Role of Nicotinamide Adenine Dinucleotide and Related Precursors as Therapeutic Targets for Age-Related Degenerative Diseases: Rationale, Biochemistry, Pharmacokinetics, and Outcomes. Antioxid Redox Signal 2019; 30:251-294. [PMID: 29634344 PMCID: PMC6277084 DOI: 10.1089/ars.2017.7269] [Citation(s) in RCA: 128] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 02/22/2018] [Accepted: 02/22/2018] [Indexed: 12/20/2022]
Abstract
Significance: Nicotinamide adenine dinucleotide (NAD+) is an essential pyridine nucleotide that serves as an essential cofactor and substrate for a number of critical cellular processes involved in oxidative phosphorylation and ATP production, DNA repair, epigenetically modulated gene expression, intracellular calcium signaling, and immunological functions. NAD+ depletion may occur in response to either excessive DNA damage due to free radical or ultraviolet attack, resulting in significant poly(ADP-ribose) polymerase (PARP) activation and a high turnover and subsequent depletion of NAD+, and/or chronic immune activation and inflammatory cytokine production resulting in accelerated CD38 activity and decline in NAD+ levels. Recent studies have shown that enhancing NAD+ levels can profoundly reduce oxidative cell damage in catabolic tissue, including the brain. Therefore, promotion of intracellular NAD+ anabolism represents a promising therapeutic strategy for age-associated degenerative diseases in general, and is essential to the effective realization of multiple benefits of healthy sirtuin activity. The kynurenine pathway represents the de novo NAD+ synthesis pathway in mammalian cells. NAD+ can also be produced by the NAD+ salvage pathway. Recent Advances: In this review, we describe and discuss recent insights regarding the efficacy and benefits of the NAD+ precursors, nicotinamide (NAM), nicotinic acid (NA), nicotinamide riboside (NR), and nicotinamide mononucleotide (NMN), in attenuating NAD+ decline in degenerative disease states and physiological aging. Critical Issues: Results obtained in recent years have shown that NAD+ precursors can play important protective roles in several diseases. However, in some cases, these precursors may vary in their ability to enhance NAD+ synthesis via their location in the NAD+ anabolic pathway. Increased synthesis of NAD+ promotes protective cell responses, further demonstrating that NAD+ is a regulatory molecule associated with several biochemical pathways. Future Directions: In the next few years, the refinement of personalized therapy for the use of NAD+ precursors and improved detection methodologies allowing the administration of specific NAD+ precursors in the context of patients' NAD+ levels will lead to a better understanding of the therapeutic role of NAD+ precursors in human diseases.
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Affiliation(s)
- Nady Braidy
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia
| | - Jade Berg
- Australasian Research Institute, Sydney Adventist Hospital, Sydney, Australia
| | | | - Fatemeh Khorshidi
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia
| | - Anne Poljak
- Mark Wainwright Analytical Centre, University of New South Wales, Sydney, Australia
- School of Medical Sciences, University of New South Wales, Sydney, Australia
| | - Tharusha Jayasena
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia
| | - Ross Grant
- Australasian Research Institute, Sydney Adventist Hospital, Sydney, Australia
- School of Medical Sciences, University of New South Wales, Sydney, Australia
- Sydney Medical School, University of Sydney, Sydney, Australia
| | - Perminder Sachdev
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Sydney, Australia
- Neuropsychiatric Institute, Euroa Centre, Prince of Wales Hospital, Sydney, Australia
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Clement J, Wong M, Poljak A, Sachdev P, Braidy N. The Plasma NAD + Metabolome Is Dysregulated in "Normal" Aging. Rejuvenation Res 2018; 22:121-130. [PMID: 30124109 PMCID: PMC6482912 DOI: 10.1089/rej.2018.2077] [Citation(s) in RCA: 124] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Nicotinamide adenine dinucleotide (NAD+) is an essential pyridine nucleotide that serves as an electron carrier in cellular metabolism and plays a crucial role in the maintenance of balanced redox homeostasis. Quantification of NAD+:NADH and NADP+:NADPH ratios are pivotal to a wide variety of cellular processes, including intracellular secondary messenger signaling by CD38 glycohydrolases, DNA repair by poly(adenosine diphosphate ribose) polymerase (PARP), epigenetic regulation of gene expression by NAD-dependent histone deacetylase enzymes known as sirtuins, and regulation of the oxidative pentose phosphate pathway. We quantified changes in the NAD+ metabolome in plasma samples collected from consenting healthy human subjects across a wide age range (20-87 years) using liquid chromatography coupled to tandem mass spectrometry. Our data show a significant decline in the plasma levels of NAD+, NADP+, and other important metabolites such as nicotinic acid adenine dinucleotide (NAAD) with age. However, an age-related increase in the reduced form of NAD+ and NADP+-NADH and NADPH-and nicotinamide (NAM), N-methyl-nicotinamide (MeNAM), and the products of adenosine diphosphoribosylation, including adenosine diphosphate ribose (ADPR) was also reported. Whereas, plasma levels of nicotinic acid (NA), nicotinamide mononucleotide (NMN), and nicotinic acid mononucleotide (NAMN) showed no statistically significant changes across age groups. Taken together, our data cumulatively suggest that age-related impairments are associated with corresponding alterations in the extracellular plasma NAD+ metabolome. Our future research will seek to elucidate the role of modulating NAD+ metabolites in the treatment and prevention of age-related diseases.
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Affiliation(s)
| | - Matthew Wong
- 2 Centre for Healthy Brain Ageing, University of New South Wales, School of Psychiatry, Sydney, Australia
| | - Anne Poljak
- 2 Centre for Healthy Brain Ageing, University of New South Wales, School of Psychiatry, Sydney, Australia.,3 Mark Wainwright Analytical Centre, University of New South Wales, Sydney, Australia.,4 School of Medical Sciences, University of New South Wales, Sydney, Australia
| | - Perminder Sachdev
- 2 Centre for Healthy Brain Ageing, University of New South Wales, School of Psychiatry, Sydney, Australia.,5 Neuropsychiatric Institute, Euroa Centre, Prince of Wales Hospital, Sydney, Australia
| | - Nady Braidy
- 2 Centre for Healthy Brain Ageing, University of New South Wales, School of Psychiatry, Sydney, Australia
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Nicotinamide adenine dinucleotide and its related precursors for the treatment of Alzheimer's disease. Curr Opin Psychiatry 2018; 31:160-166. [PMID: 29232252 DOI: 10.1097/yco.0000000000000394] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
PURPOSE OF REVIEW The current review discusses the biology and metabolism of the essential pyridine nucleotide nicotinamide adenine dinucleotide (NAD+) in the central nervous system. We also review recent work suggesting important neuroprotective effects that may be associated with the promotion of NAD+ levels through NAD+ precursors against Alzheimer's disease. RECENT FINDINGS Perturbations in the physiological homoeostatic state of the brain during the ageing process can lead to impaired cellular function, and ultimately leads to loss of brain integrity and accelerates cognitive and memory decline. Increased oxidative stress has been shown to impair normal cellular bioenergetics and enhance the depletion of the essential nucleotides NAD+ and ATP. NAD+ and its precursors have been shown to improve cellular homoeostasis based on association with dietary requirements, and treatment and management of several inflammatory and metabolic diseases in vivo. Cellular NAD+ pools have been shown to be reduced in the ageing brain, and treatment with NAD+ precursors has been hypothesized to restore these levels and attenuate disruption in cellular bioenergetics. SUMMARY NAD+ and its precursors may represent an important therapeutic strategy to maintain optimal cellular homoeostatic functions in the brain. NAD+ precursors are available in a variety of foods and may be translated to the clinic in the form of supplements.
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Gao J, Xu K, Liu H, Liu G, Bai M, Peng C, Li T, Yin Y. Impact of the Gut Microbiota on Intestinal Immunity Mediated by Tryptophan Metabolism. Front Cell Infect Microbiol 2018; 8:13. [PMID: 29468141 PMCID: PMC5808205 DOI: 10.3389/fcimb.2018.00013] [Citation(s) in RCA: 710] [Impact Index Per Article: 118.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 01/12/2018] [Indexed: 12/12/2022] Open
Abstract
The gut microbiota influences the health of the host, especially with regard to gut immune homeostasis and the intestinal immune response. In addition to serving as a nutrient enhancer, L-tryptophan (Trp) plays crucial roles in the balance between intestinal immune tolerance and gut microbiota maintenance. Recent discoveries have underscored that changes in the microbiota modulate the host immune system by modulating Trp metabolism. Moreover, Trp, endogenous Trp metabolites (kynurenines, serotonin, and melatonin), and bacterial Trp metabolites (indole, indolic acid, skatole, and tryptamine) have profound effects on gut microbial composition, microbial metabolism, the host's immune system, the host-microbiome interface, and host immune system-intestinal microbiota interactions. The aryl hydrocarbon receptor (AhR) mediates the regulation of intestinal immunity by Trp metabolites (as ligands of AhR), which is beneficial for immune homeostasis. Among Trp metabolites, AhR ligands consist of endogenous metabolites, including kynurenine, kynurenic acid, xanthurenic acid, and cinnabarinic acid, and bacterial metabolites, including indole, indole propionic acid, indole acetic acid, skatole, and tryptamine. Additional factors, such as aging, stress, probiotics, and diseases (spondyloarthritis, irritable bowel syndrome, inflammatory bowel disease, colorectal cancer), which are associated with variability in Trp metabolism, can influence Trp-microbiome-immune system interactions in the gut and also play roles in regulating gut immunity. This review clarifies how the gut microbiota regulates Trp metabolism and identifies the underlying molecular mechanisms of these interactions. Increased mechanistic insight into how the microbiota modulates the intestinal immune system through Trp metabolism may allow for the identification of innovative microbiota-based diagnostics, as well as appropriate nutritional supplementation of Trp to prevent or alleviate intestinal inflammation. Moreover, this review provides new insight regarding the influence of the gut microbiota on Trp metabolism. Additional comprehensive analyses of targeted Trp metabolites (including endogenous and bacterial metabolites) are essential for experimental preciseness, as the influence of the gut microbiota cannot be neglected, and may explain contradictory results in the literature.
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Affiliation(s)
- Jing Gao
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Kang Xu
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
| | - Hongnan Liu
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
| | - Gang Liu
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
| | - Miaomiao Bai
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
| | - Can Peng
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
| | - Tiejun Li
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
| | - Yulong Yin
- National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- Key Laboratory of Agro-Ecology, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, Changsha, China
- University of Chinese Academy of Sciences, Beijing, China
- College of Life Science, Hunan Normal University, Changsha, Hunan, China
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22
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Cervenka I, Agudelo LZ, Ruas JL. Kynurenines: Tryptophan's metabolites in exercise, inflammation, and mental health. Science 2018; 357:357/6349/eaaf9794. [PMID: 28751584 DOI: 10.1126/science.aaf9794] [Citation(s) in RCA: 750] [Impact Index Per Article: 125.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Kynurenine metabolites are generated by tryptophan catabolism and regulate biological processes that include host-microbiome signaling, immune cell response, and neuronal excitability. Enzymes of the kynurenine pathway are expressed in different tissues and cell types throughout the body and are regulated by cues, including nutritional and inflammatory signals. As a consequence of this systemic metabolic integration, peripheral inflammation can contribute to accumulation of kynurenine in the brain, which has been associated with depression and schizophrenia. Conversely, kynurenine accumulation can be suppressed by activating kynurenine clearance in exercised skeletal muscle. The effect of exercise training on depression through modulation of the kynurenine pathway highlights an important mechanism of interorgan cross-talk mediated by these metabolites. Here, we discuss peripheral mechanisms of tryptophan-kynurenine metabolism and their effects on inflammatory, metabolic, oncologic, and psychiatric disorders.
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Affiliation(s)
- Igor Cervenka
- Department of Physiology and Pharmacology, Molecular and Cellular Exercise Physiology, Karolinska Institutet, SE-17177 Stockholm, Sweden
| | - Leandro Z Agudelo
- Department of Physiology and Pharmacology, Molecular and Cellular Exercise Physiology, Karolinska Institutet, SE-17177 Stockholm, Sweden
| | - Jorge L Ruas
- Department of Physiology and Pharmacology, Molecular and Cellular Exercise Physiology, Karolinska Institutet, SE-17177 Stockholm, Sweden.
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23
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Grant RS. Indoleamine 2,3-Dioxygenase Activity Increases NAD+ Production in IFN-γ-Stimulated Human Primary Mononuclear Cells. Int J Tryptophan Res 2018; 11:1178646917751636. [PMID: 29343967 PMCID: PMC5764136 DOI: 10.1177/1178646917751636] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Accepted: 12/05/2017] [Indexed: 11/15/2022] Open
Abstract
IFN-γ activation of mononuclear phagocytes significantly increases indoleamine 2,3-dioxygenase (IDO) and flux through the kynurenine pathway (KP). However, the effect of IDO on NAD+ synthesis, the end product of KP metabolism, is unknown. To investigate this, primary human peripheral blood mononuclear cells were cultured up to 10 days and activated with IFN-γ in the presence or absence of a poly(ADP-ribose) polymerase (PARP) inhibitor. Day 10 macrophages had significantly higher NAD+ levels compared with monocytes. IFN-γ activation of macrophages resulted in the highest induction of IDO but decreased intracellular NAD+ concentrations at both 24 and 48 hours. However, IFN-γ activation of both day 6 and day 10 macrophages in the presence of a PARP inhibitor resulted in significantly higher intracellular NAD+ levels at 24 hours. This study provides evidence for the first time that an immune-mediated increase in IDO activity increases NAD+ biosynthesis concomitantly with an increase in NAD+ catabolism in primary human macrophages.
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Affiliation(s)
- Ross S Grant
- Faculty of Medicine, School of Medical Sciences, University of New South Wales, Sydney, NSW, Australia
- Australasian Research Institute, Sydney Adventist Hospital, Sydney, NSW, Australia
- Sydney Adventist Hospital Clinical School, University of Sydney, Sydney, NSW, Australia
- Ross S Grant, Faculty of Medicine, School of Medical Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
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24
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Wang Z, Gao Y, Zhang C, Hu H, Guo D, Xu Y, Xu Q, Zhang W, Deng S, Lv P, Yang Y, Ding Y, Li Q, Weng C, Chen X, Gong S, Chen H, Niu J, Tang H. Quinolinate Phosphoribosyltransferase is an Antiviral Host Factor Against Hepatitis C Virus Infection. Sci Rep 2017; 7:5876. [PMID: 28724915 PMCID: PMC5517448 DOI: 10.1038/s41598-017-06254-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 06/09/2017] [Indexed: 01/09/2023] Open
Abstract
HCV infection can decrease NAD+/NADH ratio, which could convert lipid metabolism to favor HCV replication. In hepatocytes, quinolinate phosphoribosyl transferase (QPRT) catabolizes quinolinic acid (QA) to nicotinic acid mononucleotide (NAMN) for de novo NAD synthesis. However, whether and how HCV modulates QPRT hence the lipogenesis is unknown. In this work, we found QPRT was reduced significantly in livers of patients or humanized C/OTg mice with persistent HCV infection. Mechanistic studies indicated that HCV NS3/4A promoted proteasomal degradation of QPRT through Smurf2, an E3 ubiquitin-protein ligase, in Huh7.5.1 cells. Furthermore, QPRT enzymatic activity involved in suppression of HCV replication in cells. Activation of QPRT with clofibrate (CLO) or addition of QPRT catabolite NAD both inhibited HCV replication in cells, probably through NAD+-dependent Sirt1 inhibition of cellular lipogenesis. More importantly, administration of CLO, a hypolipidemic drug used in clinics, could significantly reduce the viral load in HCV infected C/OTg mice. Take together, these results suggested that HCV infection triggered proteasomal degradation of QPRT and consequently reduced de novo NAD synthesis and lipogenesis, in favor of HCV replication. Hepatic QPRT thus likely served as a cellular factor that dampened productive HCV replication.
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Affiliation(s)
- Zhilong Wang
- The Joint Laboratory for Translational Precision Medicine of Wuhan Institute of Virology, Chinese Academy of Sciences and Guangzhou Women and Children`s Medical Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, 430071, China.,CAS Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 10049, China
| | - Yanhang Gao
- Department of Hepatology, The First Hospital of Jilin University, Changchun, Jilin, 130021, China
| | - Chao Zhang
- CAS Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Haiming Hu
- The Joint Laboratory for Translational Precision Medicine of Wuhan Institute of Virology, Chinese Academy of Sciences and Guangzhou Women and Children`s Medical Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, 430071, China
| | - Dongwei Guo
- Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Heilong Jiang, 150001, China
| | - Yi Xu
- The Joint Laboratory for Translational Precision Medicine of Wuhan Institute of Virology, Chinese Academy of Sciences and Guangzhou Women and Children`s Medical Center, Guangzhou Women and Children's Medical Center, Guangzhou, 510623, China
| | - Qiuping Xu
- The Joint Laboratory for Translational Precision Medicine of Wuhan Institute of Virology, Chinese Academy of Sciences and Guangzhou Women and Children`s Medical Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, 430071, China.,Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Weihong Zhang
- The Joint Laboratory for Translational Precision Medicine of Wuhan Institute of Virology, Chinese Academy of Sciences and Guangzhou Women and Children`s Medical Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, 430071, China
| | - Sisi Deng
- The Joint Laboratory for Translational Precision Medicine of Wuhan Institute of Virology, Chinese Academy of Sciences and Guangzhou Women and Children`s Medical Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, 430071, China
| | - Pingyun Lv
- The Joint Laboratory for Translational Precision Medicine of Wuhan Institute of Virology, Chinese Academy of Sciences and Guangzhou Women and Children`s Medical Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, 430071, China
| | - Yan Yang
- The Joint Laboratory for Translational Precision Medicine of Wuhan Institute of Virology, Chinese Academy of Sciences and Guangzhou Women and Children`s Medical Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, 430071, China
| | - Yanhua Ding
- Department of Hepatology, The First Hospital of Jilin University, Changchun, Jilin, 130021, China
| | - Qingquan Li
- Department of Hepatology, The First Hospital of Jilin University, Changchun, Jilin, 130021, China
| | - Changjiang Weng
- Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Heilong Jiang, 150001, China
| | - Xinwen Chen
- The Joint Laboratory for Translational Precision Medicine of Wuhan Institute of Virology, Chinese Academy of Sciences and Guangzhou Women and Children`s Medical Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, 430071, China
| | - Sitang Gong
- The Joint Laboratory for Translational Precision Medicine of Wuhan Institute of Virology, Chinese Academy of Sciences and Guangzhou Women and Children`s Medical Center, Guangzhou Women and Children's Medical Center, Guangzhou, 510623, China
| | - Hairong Chen
- CAS Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Junqi Niu
- Department of Hepatology, The First Hospital of Jilin University, Changchun, Jilin, 130021, China
| | - Hong Tang
- The Joint Laboratory for Translational Precision Medicine of Wuhan Institute of Virology, Chinese Academy of Sciences and Guangzhou Women and Children`s Medical Center, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei, 430071, China. .,CAS Key Laboratory of Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China. .,Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, 200031, China.
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25
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Rodriguez Cetina Biefer H, Vasudevan A, Elkhal A. Aspects of Tryptophan and Nicotinamide Adenine Dinucleotide in Immunity: A New Twist in an Old Tale. Int J Tryptophan Res 2017; 10:1178646917713491. [PMID: 28659716 PMCID: PMC5476425 DOI: 10.1177/1178646917713491] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 04/07/2017] [Indexed: 12/26/2022] Open
Abstract
Increasing evidence underscores the interesting ability of tryptophan to regulate immune responses. However, the exact mechanisms of tryptophan's immune regulation remain to be determined. Tryptophan catabolism via the kynurenine pathway is known to play an important role in tryptophan's involvement in immune responses. Interestingly, quinolinic acid, which is a neurotoxic catabolite of the kynurenine pathway, is the major pathway for the de novo synthesis of nicotinamide adenine dinucleotide (NAD+). Recent studies have shown that NAD+, a natural coenzyme found in all living cells, regulates immune responses and creates homeostasis via a novel signaling pathway. More importantly, the immunoregulatory properties of NAD+ are strongly related to the overexpression of tryptophan hydroxylase 1 (Tph1). This review provides recent knowledge of tryptophan and NAD+ and their specific and intriguing roles in the immune system. Furthermore, it focuses on the mechanisms by which tryptophan regulates NAD+ synthesis as well as innate and adaptive immune responses.
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Affiliation(s)
| | - Anju Vasudevan
- Angiogenesis and Brain Development Laboratory, Division of Basic Neuroscience, McLean Hospital and Harvard Medical School, Belmont, MA, USA
| | - Abdallah Elkhal
- Division of Transplant Surgery and Transplantation Surgery Research Laboratory, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
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26
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Moon PK, Minhas PS. Reevaluating the role of IDO1: Examining NAD+ metabolism in inflammation. J Neuroimmunol 2017; 307:31-32. [PMID: 28495134 DOI: 10.1016/j.jneuroim.2017.03.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 03/26/2017] [Indexed: 10/19/2022]
Affiliation(s)
- Peter Kim Moon
- Department of Biology, Stanford University, Stanford, CA 94305, United States
| | - Paras Singh Minhas
- Department of Neurology & Neurological Sciences, School of Medicine, Stanford University, Stanford, CA 94305, United States.
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27
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Abstract
Immune-mediated activation of tryptophan (TRYP) catabolism via the kynurenine pathway (KP) is a consistent finding in all inflammatory disorders. Several studies by our group and others have examined the neurotoxic potential of neuroreactive TRYP metabolites, including quinolinic acid (QUIN) in neuroinflammatory neurological disorders, including Alzheimer's disease (AD), multiple sclerosis, amylotropic lateral sclerosis (ALS), and AIDS related dementia complex (ADC). Our current work aims to determine whether there is any benefit to the affected individuals in enhancing the catabolism of TRYP via the KP during an immune response. Under physiological conditions, QUIN is metabolized to the essential pyridine nucleotide, nicotinamide adenine dinucleotide (NAD+), which represents an important metabolic cofactor and electron transporter. NAD+ also serves as a substrate for the DNA ‘nick sensor’ and putative nuclear repair enzyme, poly(ADP-ribose) polymerase (PARP). Free radical initiated DNA damage, PARP activation and NAD+ depletion may contribute to brain dysfunction and cell death in neuroinflammatory disease.
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Affiliation(s)
- Nady Braidy
- Centre for Healthy Brain Ageing, School of Psychiatry, University of New South Wales, Faculty of Medicine, Sydney, Australia
| | - Ross Grant
- School of Medical Sciences, University of New South Wales, Faculty of Medicine, Sydney, Australia; Australasian Research Institute, Sydney Adventist Hospital, Sydney, Australia
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28
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Ruggieri S, Orsomando G, Sorci L, Raffaelli N. Regulation of NAD biosynthetic enzymes modulates NAD-sensing processes to shape mammalian cell physiology under varying biological cues. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2015; 1854:1138-49. [PMID: 25770681 DOI: 10.1016/j.bbapap.2015.02.021] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 02/26/2015] [Accepted: 02/27/2015] [Indexed: 12/25/2022]
Abstract
In addition to its role as a redox coenzyme, NAD is a substrate of various enzymes that split the molecule to either catalyze covalent modifications of target proteins or convert NAD into biologically active metabolites. The coenzyme bioavailability may be significantly affected by these reactions, with ensuing major impact on energy metabolism, cell survival, and aging. Moreover, through the activity of the NAD-dependent deacetylating sirtuins, NAD behaves as a beacon molecule that reports the cell metabolic state, and accordingly modulates transcriptional responses and metabolic adaptations. In this view, NAD biosynthesis emerges as a highly regulated process: it enables cells to preserve NAD homeostasis in response to significant NAD-consuming events and it can be modulated by various stimuli to induce, via NAD level changes, suitable NAD-mediated metabolic responses. Here we review the current knowledge on the regulation of mammalian NAD biosynthesis, with focus on the relevant rate-limiting enzymes. This article is part of a Special Issue entitled: Cofactor-dependent proteins: evolution, chemical diversity and bio-applications.
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Affiliation(s)
- Silverio Ruggieri
- Department of Agricultural, Food and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy
| | - Giuseppe Orsomando
- Department of Clinical Sciences, Section of Biochemistry, Polytechnic University of Marche, Ancona, Italy
| | - Leonardo Sorci
- Department of Clinical Sciences, Section of Biochemistry, Polytechnic University of Marche, Ancona, Italy
| | - Nadia Raffaelli
- Department of Agricultural, Food and Environmental Sciences, Polytechnic University of Marche, Ancona, Italy.
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29
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Protective effect of nicotinamide on high glucose/palmitate-induced glucolipotoxicity to INS-1 beta cells is attributed to its inhibitory activity to sirtuins. Arch Biochem Biophys 2013; 535:187-96. [PMID: 23562377 DOI: 10.1016/j.abb.2013.03.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Revised: 03/14/2013] [Accepted: 03/17/2013] [Indexed: 11/20/2022]
Abstract
This study was initiated to determine whether the protective effect of nicotinamide (NAM) on high glucose/palmitate (HG/PA)-induced INS-1 beta cell death was due to its role as an anti-oxidant, nicotinamide dinucleotide (NAD+) precursor, or inhibitor of NAD+-consuming enzymes such as poly (ADP-ribose) polymerase (PARP) or sirtuins. All anti-oxidants tested were not protective against HG/PA-induced INS-1 cell death. Direct supplementation of NAD+ or indirect supplementation through NAD+ salvage or de novo pathway did not protect the death. Knockdown of the NAD+ salvage pathway enzymes such as nicotinamide phosphoribosyl transferase (NAMPT) or nicotinamide mononucleotide adenyltransferase (NMNAT) did not augment death. On the other hand, pharmacological inhibition or knockdown of PARP did not affect death. However, sirtinol as an inhibitor of NAD-dependant deacetylase or knockdown of SIRT3 or SIRT4 significantly reduced the HG/PA-induced death. These data suggest that protective effect of NAM on beta cell glucolipotoxicity is attributed to its inhibitory activity on sirtuins.
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30
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Sahm F, Oezen I, Opitz CA, Radlwimmer B, von Deimling A, Ahrendt T, Adams S, Bode HB, Guillemin GJ, Wick W, Platten M. The endogenous tryptophan metabolite and NAD+ precursor quinolinic acid confers resistance of gliomas to oxidative stress. Cancer Res 2013; 73:3225-34. [PMID: 23548271 DOI: 10.1158/0008-5472.can-12-3831] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Quinolinic acid is a product of tryptophan degradation and may serve as a precursor for NAD(+), an important enzymatic cofactor for enzymes such as the DNA repair protein PARP. Pathologic accumulation of quinolinic acid has been found in neurodegenerative disorders including Alzheimer and Huntington disease, where it is thought to be toxic for neurons by activating the N-methyl-D-aspartate (NMDA) receptor and inducing excitotoxicity. Although many tumors including gliomas constitutively catabolize tryptophan, it is unclear whether quinolinic acid is produced in gliomas and whether it is involved in tumor progression. Here, we show that quinolinic acid accumulated in human gliomas and was associated with a malignant phenotype. Quinolinic acid was produced by microglial cells, as expression of the quinolinic acid-producing enzyme 3-hydroxyanthranilate oxygenase (3-HAO) was confined to microglia in glioma tissue. Human malignant glioma cells, but not nonneoplastic astrocytes, expressed quinolinic acid phosphoribosyltransferase (QPRT) to use quinolinic acid for NAD(+) synthesis and prevent apoptosis when de novo NAD(+) synthesis was blocked. Oxidative stress, temozolomide, and irradiation induced QPRT in glioma cells. QPRT expression increased with malignancy. In recurrent glioblastomas after radiochemotherapy, QPRT expression was associated with a poor prognosis in two independent datasets. Our data indicate that neoplastic transformation in astrocytes is associated with a QPRT-mediated switch in NAD(+) metabolism by exploiting microglia-derived quinolinic acid as an alternative source of replenishing intracellular NAD(+) pools. The elevated levels of QPRT expression increase resistance to oxidative stress induced by radiochemotherapy, conferring a poorer prognosis. These findings have implications for therapeutic approaches inducing intracellular NAD(+) depletion, such as alkylating agents or direct NAD(+) synthesis inhibitors, and identify QPRT as a potential therapeutic target in malignant gliomas.
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Affiliation(s)
- Felix Sahm
- Clinical Cooperation Unit Neuroimmunology and Brain Tumor Immunology, German Cancer Research Center (DKFZ), Frankfurt, Germany
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31
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Massudi H, Grant R, Guillemin GJ, Braidy N. NAD+ metabolism and oxidative stress: the golden nucleotide on a crown of thorns. Redox Rep 2012; 17:28-46. [PMID: 22340513 DOI: 10.1179/1351000212y.0000000001] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
In the twentieth century, NAD+ research generated multiple discoveries. Identification of the important role of NAD+ as a cofactor in cellular respiration and energy production was followed by discoveries of numerous NAD+ biosynthesis pathways. In recent years, NAD+ has been shown to play a unique role in DNA repair and protein deacetylation. As discussed in this review, there are close interactions between oxidative stress and immune activation, energy metabolism, and cell viability in neurodegenerative disorders and ageing. Profound interactions with regard to oxidative stress and NAD+ have been highlighted in the present work. This review emphasizes the pivotal role of NAD+ in the regulation of DNA repair, stress resistance, and cell death, suggesting that NAD+ synthesis through the kynurenine pathway and/or salvage pathway is an attractive target for therapeutic intervention in age-associated degenerative disorders. NAD+ precursors have been shown to slow down ageing and extend lifespan in yeasts, and protect severed axons from degeneration in animal models neurodegenerative diseases.
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Affiliation(s)
- Hassina Massudi
- Department of Pharmacology, School of Medical Sciences, University of New South Wales, Faculty of Medicine, and Australasian Research Institute, Sydney Adventist Hospital, Sydney, Australia
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32
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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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33
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Grant R, Nguyen S, Guillemin G. Kynurenine Pathway Metabolism is Involved in the Maintenance of the Intracellular NAD Concentration in Human Primary Astrocytes. Int J Tryptophan Res 2010; 3:151-6. [PMID: 22084595 PMCID: PMC3195244 DOI: 10.4137/ijtr.s4779] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
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.
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Affiliation(s)
- Ross Grant
- School of Medical Sciences, University of New South Wales, Sydney NSW Australia
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34
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Grant RS, Coggan SE, Smythe GA. The physiological action of picolinic Acid in the human brain. Int J Tryptophan Res 2009; 2:71-9. [PMID: 22084583 PMCID: PMC3195224 DOI: 10.4137/ijtr.s2469] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Picolinic Acid is an endogenous metabolite of L-tryptophan (TRP) that has been reported to possess a wide range of neuroprotective, immunological, and anti-proliferative affects within the body. However the salient physiological function of this molecule is yet to be established. The synthesis of picolinic acid as a product of the kynurenine pathway (KP) suggests that, similar to other KP metabolites, picolinic acid may play a role in the pathogenesis of inflammatory disorders within the CNS and possibly other organs. In this paper we review the limited body of literature dealing with the physiological actions of picolinic acid in the CNS and its associated synthesis via the kynurenine pathway in health and disease. Discrepancies and gaps in our current knowledge of picolinic acid are identified highlighting areas of research to promote a more complete understanding of its endogenous function in the brain.
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Affiliation(s)
- R S Grant
- School of Medical Sciences, Faculty of Medicine, University of New South Wales, Sydney NSW, 2052
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Braidy N, Grant R, Brew BJ, Adams S, Jayasena T, Guillemin GJ. Effects of Kynurenine Pathway Metabolites on Intracellular NAD Synthesis and Cell Death in Human Primary Astrocytes and Neurons. Int J Tryptophan Res 2009; 2:61-9. [PMID: 22084582 PMCID: PMC3195228 DOI: 10.4137/ijtr.s2318] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The kynurenine pathway (KP) is a major route of L-tryptophan catabolism resulting in the production of the essential pyridine nucleotide nicotinamide adenine dinucleotide, (NAD+). Up-regulation of the KP during inflammation leads to the release of a number of biologically active metabolites into the brain. We hypothesised that while some of the extracellular KP metabolites may be beneficial for intracellular NAD+ synthesis and cell survival at physiological concentrations, they may contribute to neuronal and astroglial dysfunction and cell death at pathophysiological concentrations. In this study, we found that treatment of human primary neurons and astrocytes with 3-hydroxyanthranilic acid (3-HAA), 3-hydroxykynurenine (3-HK), quinolinic acid (QUIN), and picolinic acid (PIC) at concentrations below 100 nM significantly increased intracellular NAD+ levels compared to non-treated cells. However, a dose dependent decrease in intracellular NAD+ levels and increased extracellular LDH activity was observed in human astrocytes and neurons treated with 3-HAA, 3-HK, QUIN and PIC at concentrations >100 nM and kynurenine (KYN), at concentrations above 1 μM. Intracellular NAD+ levels were unchanged in the presence of the neuroprotectant, kynurenic acid (KYNA), and a dose dependent increase in intracellular NAD+ levels was observed for TRP up to 1 mM. While anthranilic acid (AA) increased intracellular NAD+ levels at concentration below 10 μM in astrocytes. NAD+ depletion and cell death was observed in AA treated neurons at concentrations above 500 nM. Therefore, the differing responses of astrocytes and neurons to an increase in KP metabolites should be considered when assessing KP toxicity during neuroinflammation.
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Affiliation(s)
- Nady Braidy
- University of New South Wales, Faculty of Medicine, Sydney, Australia
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Coggan SE, Smythe GA, Bilgin A, Grant RS. Age and circadian influences on picolinic acid concentrations in human cerebrospinal fluid. J Neurochem 2009; 108:1220-5. [DOI: 10.1111/j.1471-4159.2009.05868.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
The etiology of multiple sclerosis (MS) is unknown but it manifests as a chronic inflammatory demyelinating disease in the central nervous system (CNS). During chronic CNS inflammation, nicotinamide adenine dinucleotide (NAD) concentrations are altered by (T helper) Th1-derived cytokines through the coordinated induction of both indoleamine 2,3-dioxygenase (IDO) and the ADP cyclase CD38 in pathogenic microglia and lymphocytes. While IDO activation may keep auto-reactive T cells in check, hyper-activation of IDO can leave neuronal CNS cells starving for extracellular sources of NAD. Existing data indicate that glia may serve critical functions as an essential supplier of NAD to neurons during times of stress. Administration of pharmacological doses of non-tryptophan NAD precursors ameliorates pathogenesis in animal models of MS. Animal models of MS involve artificially stimulated autoimmune attack of myelin by experimental autoimmune encephalomyelitis (EAE) or by viral-mediated demyelination using Thieler's murine encephalomyelitis virus (TMEV). The Wld(S) mouse dramatically resists razor axotomy mediated axonal degeneration. This resistance is due to increased efficiency of NAD biosynthesis that delays stress-induced depletion of axonal NAD and ATP. Although the Wld(S) genotype protects against EAE pathogenesis, TMEV-mediated pathogenesis is exacerbated. In this review, we contrast the role of NAD in EAE versus TMEV demyelinating pathogenesis to increase our understanding of the pharmacotherapeutic potential of NAD signal transduction pathways. We speculate on the importance of increased SIRT1 activity in both PARP-1 inhibition and the potentially integral role of neuronal CD200 interactions through glial CD200R with induction of IDO in MS pathogenesis. A comprehensive review of immunomodulatory control of NAD biosynthesis and degradation in MS pathogenesis is presented. Distinctive pharmacological approaches designed for NAD-complementation or targeting NAD-centric proteins (SIRT1, SIRT2, PARP-1, GPR109a, and CD38) are outlined towards determining which approach may work best in the context of clinical application.
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Affiliation(s)
- W Todd Penberthy
- Department of Molecular Genetics, Biochemistry, and Microbiology, University of Cincinnati, Cincinnati, Ohio 45237, USA.
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Immunosuppression routed via the kynurenine pathway: a biochemical and pathophysiologic approach. Adv Clin Chem 2008; 45:155-97. [PMID: 18429497 DOI: 10.1016/s0065-2423(07)00007-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In the past years, it has been shown that kynurenines pathway is a regulator of both the innate and the adaptive immune responses. Particularly, the initial enzyme of this pathway, indoleamine 2,3-dioxygenase (IDO), is implicated in maintaining tolerance during pregnancy, and also can be expressed in tumors to avoid the immune attack. In this chapter, we will describe how the kynurenine pathway affects the immune system with important implications both in physiology and in pathology. The incorrect activation or blockade suppressive properties of the kynurenine pathway are also implicated in a number of other diseases such as AIDS or autoimmune diseases.
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Hara T, Ogasawara N, Akimoto H, Takikawa O, Hiramatsu R, Kawabe T, Isobe KI, Nagase F. High-affinity uptake of kynurenine and nitric oxide-mediated inhibition of indoleamine 2,3-dioxygenase in bone marrow-derived myeloid dendritic cells. Immunol Lett 2007; 116:95-102. [PMID: 18179826 DOI: 10.1016/j.imlet.2007.11.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2007] [Revised: 11/14/2007] [Accepted: 11/27/2007] [Indexed: 11/26/2022]
Abstract
Indoleamine 2,3-dioxygenase (IDO)-initiated tryptophan metabolism along the kynurenine (Kyn) pathway in some dendritic cells (DC) such as plasmacytoid DC (pDC) regulates T-cell responses. It is unclear whether bone marrow-derived myeloid DC (BMDC) express functional IDO. The IDO expression was examined in CD11c(+)CD11b(+) BMDC differentiated from mouse bone marrow cells using GM-CSF. CpG oligodeoxynucleotides (CpG) induced the expression of IDO protein with the production of nitric oxide (NO) in BMDC in cultures for 24h. In the enzyme assay using cellular extracts of BMDC, the IDO activity of BMDC stimulated with CpG was enhanced by the addition of a NO synthase (NOS) inhibitor, suggesting that IDO activity was suppressed by NO production. On the other hand, the concentration of Kyn in the culture supernatant of BMDC was not increased by stimulation with CpG. Exogenously added Kyn was taken up by BMDC independently of CpG stimulation and NO production, and the uptake of Kyn was inhibited by a transport system L-specific inhibitor or high concentrations of tryptophan. The uptake of tryptophan by BMDC was markedly lower than that of Kyn. In conclusion, IDO activity in BMDC is down-regulated by NO production, whereas BMDC strongly take up exogenous Kyn.
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Affiliation(s)
- Toshiaki Hara
- Department of Medical Technology, Nagoya University School of Health Sciences, 1-20 Daikominami-1-chome, Higashi-ku, Nagoya, Aichi, 461-8673, Japan
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Kujundzić RN, Lowenthal JW. The role of tryptophan metabolism in iNOS transcription and nitric oxide production by chicken macrophage cells upon treatment with interferon gamma. Immunol Lett 2007; 115:153-9. [PMID: 18082271 DOI: 10.1016/j.imlet.2007.11.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2007] [Revised: 10/20/2007] [Accepted: 11/07/2007] [Indexed: 12/29/2022]
Abstract
The influence of de novo synthesis of nicotinamide adenine dinucleotide (NAD) through the kynurenine (KYN) pathway of tryptophan (TRP) degradation on gene transcription of inducible nitric oxide synthase (iNOS) and nitric oxide (NO) production in chicken interferon gamma (ChIFN-gamma)-stimulated and non-stimulated chicken macrophage cell line HD11 was investigated. Interferon gamma up regulation of iNOS transcription and NO production was dependent on an undisturbed flow through the KYN pathway. Inhibition of indoleamine-2,3-dioxygenase, the rate-limiting enzyme of TRP catabolism, by 1-methyl-l-tryptophan (1-mTRP) down regulated both iNOS gene transcription and NO production. Addition of KYN to 1-mTRP-treated, ChIFN-gamma-stimulated macrophages circumvented the down regulation of iNOS transcription and NO production. Inhibition of poly(ADP-ribose) polymerase (PARP), a nuclear enzyme involved in DNA repair, replication and transcription, which cleaves NAD into nicotinamide and ADP-ribose, down regulated iNOS gene transcription and NO production in ChIFN-gamma-stimulated HD11 cells. Our results suggest that prevention of NAD depletion in HD11 cells by ChIFN-gamma-mediated induction of IDO facilitates iNOS transcription and NO production. This effect is most likely a result of PARP1 automodification in the presence of NAD, known to facilitate transcription by changing chromatin structure and to allow NFkappaB binding to iNOS promoter which is hindered by direct protein-protein interaction between NFkappaB and unmodified PARP1.
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Affiliation(s)
- Renata Novak Kujundzić
- Division of molecular medicine, Ruder Bosković Institute, Bijenicka 54, 10000 Zagreb, Croatia.
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Keskin DB, Marshall B, Munn D, Mellor AL, Gearhart DA. Decreased protein nitration in macrophages that overexpress indoleamine 2, 3-dioxygenase. Cell Mol Biol Lett 2006; 12:82-102. [PMID: 17103092 PMCID: PMC6275707 DOI: 10.2478/s11658-006-0048-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2006] [Accepted: 09/26/2006] [Indexed: 11/20/2022] Open
Abstract
The activity of indoleamine 2, 3-dioxygenase (IDO; E.C. 1.13.11.42) catalyzes the oxidative cleavage of tryptophan to form kynurenine. IDO activity consumes superoxide anions; therefore, we postulated that over-expression of IDO might mitigate superoxide-anion dependent, oxidative modification of cellular proteins in vitro. We prepared and characterized RAW 264.7 macrophages that were stably transfected with either an IDO expression vector or the control (empty) vector. We detected IDO mRNA, protein, and enzyme activity in the IDO-transfected macrophages, but not in the macrophages transfected with the empty vector. To generate superoxide anions in situ, we treated the IDO-and control-transfected cultures with xanthine or hypoxanthine, and then used ELISA methods to quantitate the relative levels of oxidatively modified proteins in total cell lysates. The levels of protein carbonyls were similar in IDO-transfected and vector-transfected macrophages; however, protein nitration was significantly less in IDO-transfected cells compared to control transfectants. In addition, steady-state levels of superoxide anions were significantly lower in the IDO-transfected cultures compared with control transfectants. Our results are consistent with the concept that, besides degrading tryptophan, IDO activity may protect cells from oxidative damage.
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Affiliation(s)
- Derin B. Keskin
- Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA 30912 USA
| | - Brendan Marshall
- Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA 30912 USA
| | - David Munn
- Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA 30912 USA
| | - Andrew L. Mellor
- Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA 30912 USA
| | - Debra A. Gearhart
- Cellular Biology and Anatomy, Medical College of Georgia, Augusta, GA 30912 USA
- Department of Veterans Affairs Medical Center Medical Research Service, Augusta, Georgia USA
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Iqbal J, Zaidi M. TNF regulates cellular NAD+ metabolism in primary macrophages. Biochem Biophys Res Commun 2006; 342:1312-8. [PMID: 16516847 DOI: 10.1016/j.bbrc.2006.02.109] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2006] [Accepted: 02/16/2006] [Indexed: 11/18/2022]
Abstract
The inflammatory cytokine TNF is known to affect glucose and lipid metabolism, where its action leads to a cachexic state. Despite a well-established connection of TNF to metabolism, the relationship between TNF and NAD(+) metabolism remains unclear. In this report, we evaluated the effects of TNF on NAD(+) metabolism in cells that are TNF's primary autocrine target-macrophages. We designed real-time PCR primers to all NAD(+) metabolic enzymes, which we used to examine TNF-induced changes over time. We found that TNF paradoxically up-regulated enzymes that served to increase NAD(+) levels, such as IDO and PBEF, as well as enzymes that decrease NAD(+) levels, such as CD38 and CD157. The significance of these mRNA changes was evaluated by examining TNF-mediated changes in cellular NAD(+) levels. Treatment of macrophages with TNF decreased NAD(+) levels over time, suggesting that increases in NAD(+)-degrading enzymes were dominant. To evaluate whether this was the case, we measured TNF-mediated changes in NAD(+) levels in animals where CD38 was genetically deleted. In CD38-/- macrophages, the effects of TNF were reversed, with TNF increasing NAD(+) levels over time. The significance of our findings is threefold: (1) we establish that TNF affects NAD(+) metabolism by regulating the expression of major NAD(+) metabolic enzymes, (2) TNF-induced decreases in cellular NAD(+) levels were carried out through the up-regulation of extracellularly situated enzymes, and (3) we provide a mechanism for the observed clinical connection of TNF-dependent diseases to tissue reductions in NAD(+) content.
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Affiliation(s)
- Jameel Iqbal
- Department of Endocrinology and Mount Sinai Bone Program, Mount Sinai School of Medicine, New York, NY 10029, USA
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Szabó C. Pathophysiological aspects of cellular pyridine nucleotide metabolism: focus on the vascular endothelium. Review. ACTA ACUST UNITED AC 2004; 90:175-93. [PMID: 14594189 DOI: 10.1556/aphysiol.90.2003.3.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In recent years, pyridine nucleotides NAD(H) and NADP(H) have been established as an important molecules in physiological and pathophysiological signaling and cell injury pathways. Protein modification is catalyzed by ADP-ribosyl transferases that attach the ADP-ribose moiety of NAD+ to specific aminoacid residues of the acceptor proteins, with significant changes in the function of these acceptors. Mono(ADP-ribosyl)ation reactions have been implicated to play a role both in physiological responses and in cellular responses to bacterial toxins. Cyclic ADP-ribose formation also utilizes NAD+ and primarily serves as physiological, signal transduction mechanisms regulating intracellular calcium homeostasis. In pathophysiological conditions associated with oxidative stress (such as various forms of inflammation and reperfusion injury), activation of the nuclear enzyme poly(ADP-ribose) polymerase (PARP) occurs, with subsequent, substantial fall in cellular NAD+ and ATP levels, which can determine the viability and function of the affected cells. In addition, NADPH oxidases can significantly affect the balance and fate of NAD+ and NADP in oxidatively stressed cells and can facilitate the generation of various positive feedback cycles of injury. Under severe oxidant conditions, direct oxidative damage to NAD+ has also been reported. The current review focuses on PARP and on NADPH oxidases, as pathophysiologically relevant factors in creating disturbances in the cellular pyridine nucleotide balance. A separate section describes how these mechanisms apply to the pathogenesis of endothelial cell injury in selected cardiovascular pathophysiological conditions.
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Affiliation(s)
- Cs Szabó
- Institute of Human Physiology and Clinical Experimental Research, Semmelweis University, Budapest, Hungary.
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Grant R, Kapoor V. Inhibition of indoleamine 2,3-dioxygenase activity in IFN-gamma stimulated astroglioma cells decreases intracellular NAD levels. Biochem Pharmacol 2003; 66:1033-6. [PMID: 12963490 DOI: 10.1016/s0006-2952(03)00464-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Astroglia provide essential metabolic and neurotropic support to cells within the CNS and participate in the cellular immune response with microglia/macrophages following activation by the pro-inflammatory cytokine IFN-gamma. Activation of glial cells results in local oxidative stress and induction of a number of proteins including the enzyme indoleamine 2,3-dioxygenase (IDO). As a rate-limiting enzyme, IDO regulates tryptophan catabolism via the kynurenine pathway producing a series of metabolic precursors (some of which are neurotoxic) before complete oxidation to the essential pyridine nucleotide NAD. Inhibition of this pathway may therefore prove therapeutic in neuroinflammatory disease by reducing production of cell toxins. However, kynurenine metabolism may also be cytoprotective through de novo synthesis of cellular NAD levels. We investigated the hypothesis that IDO activity is directly involved in maintenance of intracellular [NAD] in activated astroglial cells through control of de novo synthesis. Exposure to IFN-gamma increased IDO activity from 7+/-1 nmol to 129+/-11 nmol kynurenine/hr/mg protein. Inhibition of IDO activity with either 6-chloro-D-tryptophan (competitive inhibition), or 3-ethoxy beta-carboline (non-competitive inhibition) resulted in a dose-dependent decrease in IDO activity that correlated directly with decreasing [NAD] (R(2)=0.92 and 0.81, respectively). These results support the hypothesis that one important consequence of increasing IDO activity in astroglial cells during inflammation is to maintain NAD levels through de novo synthesis from tryptophan. Inhibition of kynurenine pathway metabolism under these conditions may significantly decrease cell viability and CNS functions unless alternate precursors for NAD synthesis are available.
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Affiliation(s)
- Ross Grant
- Biomedical Mass Spectrometry Facility, Faculty of Medicine, University of NSW, Sydney 2000, Australia.
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Bitterman KJ, Medvedik O, Sinclair DA. Longevity regulation in Saccharomyces cerevisiae: linking metabolism, genome stability, and heterochromatin. Microbiol Mol Biol Rev 2003; 67:376-99, table of contents. [PMID: 12966141 PMCID: PMC193872 DOI: 10.1128/mmbr.67.3.376-399.2003] [Citation(s) in RCA: 165] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
When it was first proposed that the budding yeast Saccharomyces cerevisiae might serve as a model for human aging in 1959, the suggestion was met with considerable skepticism. Although yeast had proved a valuable model for understanding basic cellular processes in humans, it was difficult to accept that such a simple unicellular organism could provide information about human aging, one of the most complex of biological phenomena. While it is true that causes of aging are likely to be multifarious, there is a growing realization that all eukaryotes possess surprisingly conserved longevity pathways that govern the pace of aging. This realization has come, in part, from studies of S. cerevisiae, which has emerged as a highly informative and respected model for the study of life span regulation. Genomic instability has been identified as a major cause of aging, and over a dozen longevity genes have now been identified that suppress it. Here we present the key discoveries in the yeast-aging field, regarding both the replicative and chronological measures of life span in this organism. We discuss the implications of these findings not only for mammalian longevity but also for other key aspects of cell biology, including cell survival, the relationship between chromatin structure and genome stability, and the effect of internal and external environments on cellular defense pathways. We focus on the regulation of replicative life span, since recent findings have shed considerable light on the mechanisms controlling this process. We also present the specific methods used to study aging and longevity regulation in S. cerevisiae.
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Affiliation(s)
- Kevin J Bitterman
- Department of Pathology, Harvard Medical School, Boston, Massachusetts 02115, USA
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Abstract
The immune system continuously modulates the balance between responsiveness to pathogens and tolerance to non-harmful antigens. The mechanisms that mediate tolerance are not well understood, but recent findings have implicated tryptophan catabolism through the kynurenine metabolic pathway as one of many mechanisms involved. The enzymes that break down tryptophan through this pathway are found in numerous cell types, including cells of the immune system. Some of these enzymes are induced by immune activation, including the rate limiting enzyme present in macrophages and dendritic cells, indoleamine 2,3-dioxygenase (IDO). It has recently been found that inhibition of IDO can result in the rejection of allogenic fetuses, suggesting that tryptophan breakdown is necessary for maintaining aspects of immune tolerance. Two theories have been proposed to explain how tryptophan catabolism facilitates tolerance. One theory posits that tryptophan breakdown suppresses T cell proliferation by dramatically reducing the supply of this critical amino acid. The other theory postulates that the downstream metabolites of tryptophan catabolism act to suppress certain immune cells, probably by pro-apoptotic mechanisms. Reconciling these disparate views is crucial to understanding immune-related tryptophan catabolism and the roles it plays in immune tolerance. In this review we examine the issue in detail, and offer additional insight provided by studies with antibodies to quinolinate, a tryptophan catabolite which is also necessary for nicotinamide adenine dinucleotide (NAD +) production. In addition to the immunomodulatory actions of tryptophan catabolites, we discuss the possible involvement of quinolinate as a means of replenishing NAD + in leucocytes, which is depleted by oxidative stress during an immune response.
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Affiliation(s)
- John R Moffett
- Department of Anatomy, Uniformed Services University of the Health Sciences, Building C, Room 2109, 4301 Jones Bridge Road, Bethesda, MD 20814, USA.
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Chiarugi A, Rovida E, Dello Sbarba P, Moroni F. Tryptophan availability selectively limits NO-synthase induction in macrophages. J Leukoc Biol 2003; 73:172-7. [PMID: 12525575 DOI: 10.1189/jlb.0502220] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
We studied the effects of tryptophan (TRP) availability on the synthesis and release of nitric oxide (NO) and tumor necrosis factor alpha (TNF-alpha) in interferon-gamma (IFN-gamma)-activated murine macrophages of the BAC1.2F5 cell line. IFN-gamma (100 U/ml) not only increased the synthesis and release of NO and TNF-alpha from these cells but also induced indoleamine-2,3-dioxygenase, the rate-limiting enzyme of TRP catabolism. This led to an increased metabolic flow through the kynurenine pathway and significantly decreased TRP levels in macrophage incubation media. Low TRP concentrations in the media, however, modified IFN-gamma effects. In TRP-"starved" cultures, in fact, the IFN-gamma-mediated NO synthase induction was significantly reduced, and the increased TNF-alpha synthesis and release were not affected. Our results suggest that a reduced local TRP availability may modify macrophage function and possibly the outcome of immune responses.
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Affiliation(s)
- Alberto Chiarugi
- Department of Preclinical and Clinical Pharmacology, University of Florence, Viale Pieraccini 6, 50139 Florence, Italy
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Xie G, Bonner CA, Jensen RA. Dynamic diversity of the tryptophan pathway in chlamydiae: reductive evolution and a novel operon for tryptophan recapture. Genome Biol 2002; 3:research0051. [PMID: 12225590 PMCID: PMC126876 DOI: 10.1186/gb-2002-3-9-research0051] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2002] [Revised: 05/06/2002] [Accepted: 07/02/2002] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Complete genomic sequences of closely related organisms, such as the chlamydiae, afford the opportunity to assess significant strain differences against a background of many shared characteristics. The chlamydiae are ubiquitous intracellular parasites that are important pathogens of humans and other organisms. Tryptophan limitation caused by production of interferon-gamma by the host and subsequent induction of indoleamine dioxygenase is a key aspect of the host-parasite interaction. It appears that the chlamydiae have learned to recognize tryptophan depletion as a signal for developmental remodeling. The consequent non-cultivable state of persistence can be increasingly equated to chronic disease conditions. RESULTS The genes encoding enzymes of tryptophan biosynthesis were the focal point of this study. Chlamydophila psittaci was found to possess a compact operon containing PRPP synthase, kynureninase, and genes encoding all but the first step of tryptophan biosynthesis. All but one of the genes exhibited translational coupling. Other chlamydiae (Chlamydia trachomatis, C. muridarum and Chlamydophila pneumoniae) lack genes encoding PRPP synthase, kynureninase, and either lack tryptophan-pathway genes altogether or exhibit various stages of reductive loss. The origin of the genes comprising the trp operon does not seem to have been from lateral gene transfer. CONCLUSIONS The factors that accommodate the transition of different chlamydial species to the persistent (chronic) state of pathogenesis include marked differences in strategies deployed to obtain tryptophan from host resources. C. psittaci appears to have a novel mechanism for intercepting an early intermediate of tryptophan catabolism and recycling it back to tryptophan. In effect, a host-parasite metabolic mosaic has evolved for tryptophan recycling.
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Affiliation(s)
- Gary Xie
- Department of Microbiology and Cell Science, Gainesville, FL 32611, USA
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Abstract
The model organism Saccharomyces cerevisiae is providing new insights into the molecular and cellular changes that are related to aging. The yeast protein Sir2p (Silent Information Regulator 2) is a histone deacetylase involved in transcriptional silencing and the control of genomic stability. Recent results have led to the identification of Sir2p as a crucial determinant of yeast life span. Dosage, intracellular localization, and activity of Sir2p all have important effects on yeast longevity. For instance, calorie restriction apparently increases yeast life span by increasing Sir2p activity. Since Sir2p-related proteins have been identified in many prokaryotic and eukaryotic organisms, the fundamental principles derived from the studies in yeast may prove valuable in directing our future research toward an understanding of the mechanisms of aging in higher eukaryotes. BioEssays 23:327-332, 2001.
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Affiliation(s)
- P A Defossez
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA.
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