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Fongsaran C, Dineley KT, Paessler S, Cisneros IE. VEEV TC-83 Triggers Dysregulation of the Tryptophan-Kynurenine Pathway in the Central Nervous System That Correlates with Cognitive Impairment in Tg2576 Mice. Pathogens 2024; 13:397. [PMID: 38787249 PMCID: PMC11124172 DOI: 10.3390/pathogens13050397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 04/29/2024] [Accepted: 05/06/2024] [Indexed: 05/25/2024] Open
Abstract
Neurodegenerative diseases are chronic conditions affecting the central nervous system (CNS). Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the accumulation of amyloid beta in the limbic and cortical brain regions. AD is presumed to result from genetic abnormalities or environmental factors, including viral infections, which may have deleterious, long-term effects. In this study, we demonstrate that the Venezuelan equine encephalitis virus (VEEV) commonly induces neurodegeneration and long-term neurological or cognitive sequelae. Notably, the effects of VEEV infection can persistently influence gene expression in the mouse brain, suggesting a potential link between the observed neurodegenerative outcomes and long-term alterations in gene expression. Additionally, we show that alphavirus encephalitis exacerbates the neuropathological profile of AD through crosstalk between inflammatory and kynurenine pathways, generating a range of metabolites with potent effects. Using a mouse model for β-amyloidosis, Tg2576 mice, we found that cognitive deficits and brain pathology were more severe in Tg2576 mice infected with VEEV TC-83 compared to mock-infected controls. Thus, during immune activation, the kynurenine pathway plays a more active role in the VEEV TC-83-infected cells, leading to increases in the abundance of transcripts related to the kynurenine pathway of tryptophan metabolism. This pathway generates several metabolites with potent effects on neurotransmitter systems as well as on inflammation, as observed in VEEV TC-83-infected animals.
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Affiliation(s)
- Chanida Fongsaran
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA; (C.F.); (S.P.)
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX 77555, USA
- Neuroinfectious Diseases, University of Texas Medical Branch, Galveston, TX 77555, USA;
| | - Kelly T. Dineley
- Neuroinfectious Diseases, University of Texas Medical Branch, Galveston, TX 77555, USA;
- Mitchell Center for Neurodegenerative Diseases, Department of Neurology, University of Texas Medical Branch, Galveston, TX 77555, USA
- Center for Addiction Sciences and Therapeutics, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Slobodan Paessler
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA; (C.F.); (S.P.)
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX 77555, USA
- Neuroinfectious Diseases, University of Texas Medical Branch, Galveston, TX 77555, USA;
| | - Irma E. Cisneros
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA; (C.F.); (S.P.)
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX 77555, USA
- Neuroinfectious Diseases, University of Texas Medical Branch, Galveston, TX 77555, USA;
- Center for Addiction Sciences and Therapeutics, University of Texas Medical Branch, Galveston, TX 77555, USA
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2
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Fathi M, Vakili K, Yaghoobpoor S, Tavasol A, Jazi K, Mohamadkhani A, Klegeris A, McElhinney A, Mafi Z, Hajiesmaeili M, Sayehmiri F. Dynamic changes in kynurenine pathway metabolites in multiple sclerosis: A systematic review. Front Immunol 2022; 13:1013784. [PMID: 36426364 PMCID: PMC9680557 DOI: 10.3389/fimmu.2022.1013784] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Accepted: 10/04/2022] [Indexed: 11/05/2022] Open
Abstract
Background Multiple sclerosis (MS) is a debilitating neurodegenerative disorder characterized by axonal damage, demyelination, and perivascular inflammatory lesions in the white matter of the central nervous system (CNS). Kynurenine pathway (KP), which is the major route of tryptophan (TRP) metabolism, generates a variety of neurotoxic as well as neuroprotective compounds, affecting MS pathology and the severity of impairments. Alterations in KP have been described not only in MS, but also in various psychiatric and neurodegenerative diseases. The purpose of this systematic review is to investigate the previously reported dysregulation of KP and differences in its metabolites and enzymes in patients with MS compared to healthy control subjects. Method Electronic databases of PubMed, Scopus, Cochrane Database of Systematic Reviews, and Web of Science were searched to identify studies measuring concentrations of KP metabolites and enzymes in MS patients and control subjects. The following metabolites and enzymes implicated in the KP were investigated: TRP, kynurenine (KYN), kynurenic acid (KYNA), quinolinic acid (QUIN), picolinic acid (PIC), hydroxyindoleacetic acid (HIAA), indoleamine 2,3-dioxygenase (IDO), kynurenine aminotransferase (KAT), and their related ratios. Result Ten studies were included in our systematic review. Our review demonstrates that IDO expression is reduced in the peripheral blood mononuclear cells (PBMCs) of MS patients compared to healthy controls. Also, increased levels of QUIN and QUIN/KYNA in the serum and cerebrospinal fluid (CSF) of MS patients is observed. Differences in levels of other metabolites and enzymes of KP are also reported in some of the reviewed studies, however there are discrepancies among the included reports. Conclusion The results of this investigation suggest a possible connection between alterations in the levels of KP metabolite or enzymes and MS. QUIN levels in CSF were higher in MS patients than in healthy controls, suggesting that QUIN may be involved in the pathogenesis of MS. The data indicate that differences in the serum/blood or CSF levels of certain KP metabolites and enzymes could potentially be used to differentiate between MS patients and control subjects.
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Affiliation(s)
- Mobina Fathi
- Student Research Committee, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Kimia Vakili
- Student Research Committee, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Shirin Yaghoobpoor
- Student Research Committee, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Arian Tavasol
- Student Research Committee, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Kimia Jazi
- Faculty of Medicine, Medical University of Qom, Qom, Iran
| | - Ashraf Mohamadkhani
- Liver and Pancreatobiliary Diseases Research Center, Digestive Disease Research Institute, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Andis Klegeris
- Department of Biology, Faculty of Science, University of British Columbia, Kelowna, BC, Canada
| | - Alyssa McElhinney
- Department of Biology, Faculty of Science, University of British Columbia, Kelowna, BC, Canada
| | - Zahedeh Mafi
- Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammadreza Hajiesmaeili
- Critical Care Quality Improvement Research Center, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Fatemeh Sayehmiri
- Student Research Committee, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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3
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Kucukkarapinar M, Yay-Pence A, Yildiz Y, Buyukkoruk M, Yaz-Aydin G, Deveci-Bulut TS, Gulbahar O, Senol E, Candansayar S. Psychological outcomes of COVID-19 survivors at sixth months after diagnose: the role of kynurenine pathway metabolites in depression, anxiety, and stress. J Neural Transm (Vienna) 2022; 129:1077-1089. [PMID: 35796878 PMCID: PMC9261222 DOI: 10.1007/s00702-022-02525-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 06/20/2022] [Indexed: 10/31/2022]
Abstract
Coronavirus disease 2019 (COVID-19) has resulted in long-term psychiatric symptoms because of the immunologic response to the virus itself as well as fundamental life changes related to the pandemic. This immune response leads to altered tryptophan (TRP)-kynurenine (KYN) pathway (TKP) metabolism, which plays an essential role in the pathophysiology of mental illnesses. We aimed to define TKP changes as a potential underlying mechanism of psychiatric disorders in post-COVID-19 patients. We measured plasma levels of several TKP markers, including KYN, TRP, kynurenic acid (KYNA), 3-hydroxykynurenine (3-HK), and quinolinic acid (QUIN), as well as the TRP/KYN, KYNA/3-HK, and KYNA/QUIN ratios, in 90 post-COVID-19 patients (on the first day of hospitalization) and 59 healthy controls (on the first admission to the Check-Up Center). An online questionnaire that included the Depression, Anxiety and Stress Scale-21 (DASS-21) was used 6 months after the initial assessment in both groups. A total of 32.2% of participants with COVID-19 showed depressive symptoms, 21.1% exhibited anxiety, and 33.3% had signs of stress at follow-up, while 6.6% of healthy controls exhibited depressive and anxiety symptoms and 18.6% had signs of stress. TRP and 3-HK were negative predictors of anxiety and stress, but KYN positively predicted anxiety and stress. Moreover, TRP negatively predicted depression, while KYNA/3-HK was a negative predictor of anxiety. The correlation between depression, anxiety, and stress and TKP activation in COVID-19 could provide prospective biomarkers, especially the reduction in TRP and 3HK levels and the increase in KYN. Our results suggest that the alteration of TKP is not only a potential biomarker of viral infection-related long-term psychiatric disorders but also that the therapy targets future viral infections related to depression and anxiety.
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Affiliation(s)
- Melike Kucukkarapinar
- Psychiatry Department, Faculty of Medicine, Gazi University, Emniyet Mah., Yenimahalle, 06560, Ankara, Turkey.
| | - Aysegul Yay-Pence
- Psychiatry Department, Faculty of Medicine, Gazi University, Emniyet Mah., Yenimahalle, 06560, Ankara, Turkey
| | - Yesim Yildiz
- Department of Infectious Diseases, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Merve Buyukkoruk
- Department of Infectious Diseases, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Gizem Yaz-Aydin
- Department of Medical Biochemistry, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Tuba S Deveci-Bulut
- Department of Medical Biochemistry, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Ozlem Gulbahar
- Department of Medical Biochemistry, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Esin Senol
- Department of Infectious Diseases, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Selcuk Candansayar
- Psychiatry Department, Faculty of Medicine, Gazi University, Emniyet Mah., Yenimahalle, 06560, Ankara, Turkey
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Cisneros IE, Cunningham KA. Covid-19 interface with drug misuse and substance use disorders. Neuropharmacology 2021; 198:108766. [PMID: 34454912 PMCID: PMC8388132 DOI: 10.1016/j.neuropharm.2021.108766] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 08/09/2021] [Accepted: 08/23/2021] [Indexed: 12/26/2022]
Abstract
The coronavirus disease 2019 (Covid-19) pandemic intensified the already catastrophic drug overdose and substance use disorder (SUD) epidemic, signaling a syndemic as social isolation, economic and mental health distress, and disrupted treatment services disproportionally impacted this vulnerable population. Along with these social and societal factors, biological factors triggered by intense stress intertwined with incumbent overactivity of the immune system and the resulting inflammatory outcomes may impact the functional status of the central nervous system (CNS). We review the literature concerning SARS-CoV2 infiltration and infection in the CNS and the prospects of synergy between stress, inflammation, and kynurenine pathway function during illness and recovery from Covid-19. Taken together, inflammation and neuroimmune signaling, a consequence of Covid-19 infection, may dysregulate critical pathways and underlie maladaptive changes in the CNS, to exacerbate the development of neuropsychiatric symptoms and in the vulnerability to develop SUD. This article is part of the special Issue on 'Vulnerabilities to Substance Abuse'.
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Affiliation(s)
- I E Cisneros
- Center for Addiction Research, University of Texas Medical Branch, Galveston, TX, USA; Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA; Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, USA; Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, USA; Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, Galveston, TX, USA.
| | - K A Cunningham
- Center for Addiction Research, University of Texas Medical Branch, Galveston, TX, USA; Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, USA; Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, TX, USA
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5
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Imbeault S, Gubert Olivé M, Jungholm O, Erhardt S, Wigström H, Engberg G, Jardemark K. Blockade of KAT II Facilitates LTP in Kynurenine 3-Monooxygenase Depleted Mice. Int J Tryptophan Res 2021; 14:11786469211041368. [PMID: 34483669 PMCID: PMC8411644 DOI: 10.1177/11786469211041368] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 08/01/2021] [Indexed: 11/16/2022] Open
Abstract
Excess of brain kynurenic acid (KYNA), a neuroactive metabolite of the kynurenine
pathway, is known to elicit cognitive dysfunction. In the present study, we
investigated spatial working memory in mice with elevated levels of KYNA,
induced by targeted deletion of kynurenine 3-monooxygenase (KMO), as well as
long-term potentiation (LTP) of field excitatory postsynaptic potentials
(fEPSPs) in hippocampal brain slices from these mice. The KMO knock-out
(KMO−/−) mice performed more poorly in the spatial working memory
task as compared to their wild-type (WT) counterparts, as reflected by fewer
correct choices in a T-maze. Both fEPSPs, or LTP, did not significantly differ
between the 2 mouse strains. However, administration of PF-04859989, a
kynurenine aminotransferase (KAT) II inhibitor, limiting the production of KYNA,
facilitated fEPSP and enhanced LTP to a greater extent in hippocampal slices
from KMO−/− mice compared to WT mice. The results of the present
study point to an essential role for KYNA in modulating LTP in the hippocampus
of KMO−/− mice which may account for their dysfunctional spatial
working memory.
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Affiliation(s)
- Sophie Imbeault
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Max Gubert Olivé
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Oscar Jungholm
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Sophie Erhardt
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Holger Wigström
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.,Department of Medical Biophysics, Institute of Neuroscience and Physiology, University of Gothenburg, Sweden
| | - Göran Engberg
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Kent Jardemark
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
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6
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Yan J, Kuzhiumparambil U, Bandodkar S, Dale RC, Fu S. Cerebrospinal fluid metabolomics: detection of neuroinflammation in human central nervous system disease. Clin Transl Immunology 2021; 10:e1318. [PMID: 34386234 PMCID: PMC8343457 DOI: 10.1002/cti2.1318] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 04/26/2021] [Accepted: 07/06/2021] [Indexed: 12/15/2022] Open
Abstract
The high morbidity and mortality of neuroinflammatory diseases drives significant interest in understanding the underlying mechanisms involved in the innate and adaptive immune response of the central nervous system (CNS). Diagnostic biomarkers are important to define treatable neuroinflammation. Metabolomics is a rapidly evolving research area offering novel insights into metabolic pathways, and elucidation of reliable metabolites as biomarkers for diseases. This review focuses on the emerging literature regarding the detection of neuroinflammation using cerebrospinal fluid (CSF) metabolomics in human cohort studies. Studies of classic neuroinflammatory disorders such as encephalitis, CNS infection and multiple sclerosis confirm the utility of CSF metabolomics. Additionally, studies in neurodegeneration and neuropsychiatry support the emerging potential of CSF metabolomics to detect neuroinflammation in common CNS diseases such as Alzheimer's disease and depression. We demonstrate metabolites in the tryptophan-kynurenine pathway, nitric oxide pathway, neopterin and major lipid species show moderately consistent ability to differentiate patients with neuroinflammation from controls. Integration of CSF metabolomics into clinical practice is warranted to improve recognition and treatment of neuroinflammation.
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Affiliation(s)
- Jingya Yan
- Centre for Forensic ScienceUniversity of Technology SydneySydneyNSWAustralia
| | | | - Sushil Bandodkar
- Department of Clinical BiochemistryThe Children's Hospital at WestmeadSydneyNSWAustralia
- Clinical SchoolThe Children's Hospital at WestmeadFaculty of Medicine and HealthUniversity of SydneySydneyNSWAustralia
| | - Russell C Dale
- Clinical SchoolThe Children's Hospital at WestmeadFaculty of Medicine and HealthUniversity of SydneySydneyNSWAustralia
| | - Shanlin Fu
- Centre for Forensic ScienceUniversity of Technology SydneySydneyNSWAustralia
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7
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Collier ME, Zhang S, Scrutton NS, Giorgini F. Inflammation control and improvement of cognitive function in COVID-19 infections: is there a role for kynurenine 3-monooxygenase inhibition? Drug Discov Today 2021; 26:1473-1481. [PMID: 33609782 PMCID: PMC7889466 DOI: 10.1016/j.drudis.2021.02.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 01/26/2021] [Accepted: 02/10/2021] [Indexed: 02/07/2023]
Abstract
The novel respiratory virus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), emerged during late 2019 and spread rapidly across the world. It is now recognised that the nervous system can be affected in COVID-19, with several studies reporting long-term cognitive problems in patients. The metabolic pathway of tryptophan degradation, known as the kynurenine pathway (KP), is significantly activated in patients with COVID-19. KP metabolites have roles in regulating both inflammatory/immune responses and neurological functions. In this review, we speculate on the effects of KP activation in patients with COVID-19, and how modulation of this pathway might impact inflammation and reduce neurological symptoms.
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Affiliation(s)
- Mary Ew Collier
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, UK.
| | - Shaowei Zhang
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK
| | - Nigel S Scrutton
- Manchester Institute of Biotechnology, Department of Chemistry, School of Natural Sciences, The University of Manchester, 131 Princess Street, Manchester M1 7DN, UK
| | - Flaviano Giorgini
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, UK
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8
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Turner C. Cerebrospinal fluid, neuroinflammation, and electrospray ionization mass spectrometry. Dev Med Child Neurol 2021; 63:496. [PMID: 33521939 DOI: 10.1111/dmcn.14824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/07/2021] [Indexed: 11/29/2022]
Affiliation(s)
- Charles Turner
- The WellChild Laboratory, Evelina London Children's Hospital, London, UK
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9
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Wickström R, Fowler Å, Goiny M, Millischer V, Ygberg S, Schwieler L. The Kynurenine Pathway is Differentially Activated in Children with Lyme Disease and Tick-Borne Encephalitis. Microorganisms 2021; 9:microorganisms9020322. [PMID: 33557172 PMCID: PMC7913947 DOI: 10.3390/microorganisms9020322] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/21/2021] [Accepted: 01/29/2021] [Indexed: 01/03/2023] Open
Abstract
In children, tick-borne encephalitis and neuroborreliosis are common infections affecting the central nervous system. As inflammatory pathways including cytokine expression are activated in these children and appear to be of importance for outcome, we hypothesized that induction of the kynurenine pathway may be part of the pathophysiological mechanism. Inflammatory biomarkers were analyzed in cerebrospinal fluid from 22 children with tick-borne encephalitis (TBE), 34 children with neuroborreliosis (NB) and 6 children with no central nervous system infection. Cerebrospinal fluid levels of kynurenine and kynurenic acid were increased in children with neuroborreliosis compared to the comparison group. A correlation was seen between expression of several cerebrospinal fluid cytokines and levels of kynurenine and kynurenic acid in children with neuroborreliosis but not in children with tick-borne encephalitis. These findings demonstrate a strong induction of the kynurenine pathway in children with neuroborreliosis which differs from that seen in children with tick-borne encephalitis. The importance of brain kynurenic acid (KYNA) in both immune modulation and neurotransmission raises the possibility that abnormal levels of the compound in neuroborreliosis might be of importance for the pathophysiology of the disease. Drugs targeting the enzymes of this pathway may open the venue for novel therapeutic interventions.
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Affiliation(s)
- Ronny Wickström
- Neuropediatric Unit, Department for Women’s and Children’s Health, Karolinska Institutet, 171 77 Stockholm, Sweden; (R.W.); (S.Y.)
| | - Åsa Fowler
- Division of Paediatrics, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, 141 52 Stockholm, Sweden;
| | - Michel Goiny
- Department of Physiology & Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden;
| | - Vincent Millischer
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, 1090 Vienna, Austria;
- Department of Molecular Medicine and Surgery (MMK), Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Sofia Ygberg
- Neuropediatric Unit, Department for Women’s and Children’s Health, Karolinska Institutet, 171 77 Stockholm, Sweden; (R.W.); (S.Y.)
| | - Lilly Schwieler
- Department of Physiology & Pharmacology, Karolinska Institutet, 171 77 Stockholm, Sweden;
- Correspondence: ; Tel.: +46-707489402; Fax: +46-8-310-622
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10
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Encephalitis and aseptic meningitis: short-term and long-term outcome, quality of life and neuropsychological functioning. Sci Rep 2019; 9:16158. [PMID: 31695095 PMCID: PMC6834582 DOI: 10.1038/s41598-019-52570-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 10/21/2019] [Indexed: 12/20/2022] Open
Abstract
For those surviving encephalitis, the influence on daily life of patients and their relatives may be substantial. In contrast, the prognosis after aseptic meningitis (ASM) is considered good. In this prospective study in patients with encephalitis (n = 20) and ASM (n = 46), we show that both groups experienced reduced Health Related Quality of Life (HRQoL) at two months after discharge, and that workability was reduced in 37% of the patients with ASM. However, 12 months after discharge no neuropsychological deficits were detected in the ASM group, whereas patients with encephalitis had lower scores on tests of fine motor and psychomotor skills as well as on learning and memory. We also found that for patients with encephalitis, neopterin, as a marker of Th1 cell induced macrophage activation, and a putatively neurotoxic ratio of the kynurenine pathway (KP) measured during the acute phase was associated with lower HRQoL. Our data show that not only encephalitis, but also ASM has substantial short-term influence on HRQoL and workability. For patients with encephalitis we suggest a link between immune activation and activation of the KP during the acute phase with impaired HRQoL.
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11
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Quist-Paulsen E, Aukrust P, Kran AMB, Dunlop O, Ormaasen V, Stiksrud B, Midttun Ø, Ueland T, Ueland PM, Mollnes TE, Dyrhol-Riise AM. High neopterin and IP-10 levels in cerebrospinal fluid are associated with neurotoxic tryptophan metabolites in acute central nervous system infections. J Neuroinflammation 2018; 15:327. [PMID: 30470234 PMCID: PMC6260858 DOI: 10.1186/s12974-018-1366-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 11/11/2018] [Indexed: 11/22/2022] Open
Abstract
Background The host response to intruders in the central nervous system (CNS) may be beneficial but could also be harmful and responsible for neurologic symptoms and sequelae in CNS infections. This immune response induces the activation of the kynurenine pathway (KP) with the production of neuroactive metabolites. Herein, we explored cytokine and KP responses in cerebrospinal fluid (CSF) and serum in patients with encephalitis, aseptic, and bacterial meningitis. Methods Cytokines were measured in CSF and serum by multiplex assay in adult patients with encephalitis of infectious, autoimmune or unknown etiology (n = 10), aseptic meningitis (ASM, n = 25), acute bacterial meningitis (ABM, n = 6), and disease control patients with similar symptoms but without pleocytosis in CSF (n = 42). Liquid chromatography-tandem mass spectrometry (LC-MS/ MS) was used to measure KP metabolites in CSF and serum. Results A characteristic pattern of increasing cytokine levels and KP metabolites was found in CSF from encephalitis to ASM, with the highest levels in ABM. In ASM and ABM, most inflammatory mediators, including IL-6, IL-8, and IFN-inducible protein-10 (IP-10), showed markedly elevated levels in CSF compared with serum, indicating production within the CNS. In contrast to most mediators, the highest level of IP-10 was found in the ASM group, suggesting a potential role for IP-10 in aseptic/viral meningitis. Neopterin and IP-10 were associated with marked changes in KP metabolites in CSF with increasing kynurenine/tryptophan ratio reflecting indoleamine 2,3-dioxygenase activity. Neopterin, a marker of IFN-γ activity, was associated with an unfavorable balance between neuroprotective and neurotoxic tryptophan metabolites. Conclusion We show that parenchymal and meningeal inflammations in CNS share a characteristic cytokine profile with a general immune response in the CSF with limited influence from the systemic circulation. IFN-γ activity, assessed by neopterin and IP-10 levels, may play a role in the activation of the KP pathway in these patients, potentially mediating neurotoxic effects. Electronic supplementary material The online version of this article (10.1186/s12974-018-1366-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Else Quist-Paulsen
- Department of Infectious Diseases, Oslo University Hospital, Ullevaal Hospital, P. O. Box 4956 Nydalen, N-0450, Oslo, Norway. .,Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
| | - Pål Aukrust
- Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Oslo, Norway.,Section of Clinical Immunology and Infectious Diseases, Oslo University Hospital Rikshospitalet, Oslo, Norway.,Faculty of Medicine, University of Oslo, Oslo, Norway.,K.G. Jebsen Inflammatory Research Center, University of Oslo, Oslo, Norway.,K.G. Jebsen Thrombosis Research and Expertise Center, Tromsø, Norway
| | - Anne-Marte Bakken Kran
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway.,Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Microbiology, Oslo University Hospital, Ullevaal, Oslo, Norway
| | - Oona Dunlop
- Department of Acute Medicine, Oslo University Hospital, Ullevaal, Oslo, Norway
| | - Vidar Ormaasen
- Department of Infectious Diseases, Oslo University Hospital, Ullevaal Hospital, P. O. Box 4956 Nydalen, N-0450, Oslo, Norway
| | - Birgitte Stiksrud
- Department of Infectious Diseases, Oslo University Hospital, Ullevaal Hospital, P. O. Box 4956 Nydalen, N-0450, Oslo, Norway.,Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | | | - Thor Ueland
- Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Oslo, Norway.,Faculty of Medicine, University of Oslo, Oslo, Norway.,K.G. Jebsen Inflammatory Research Center, University of Oslo, Oslo, Norway.,K.G. Jebsen Thrombosis Research and Expertise Center, Tromsø, Norway
| | | | - Tom Eirik Mollnes
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway.,K.G. Jebsen Inflammatory Research Center, University of Oslo, Oslo, Norway.,K.G. Jebsen Thrombosis Research and Expertise Center, Tromsø, Norway.,Department of Immunology, Oslo University Hospital, Oslo, Norway.,Research Laboratory, Nordland Hospital, Bodø, Norway.,Faculty of Health Sciences, University of Tromsø, Tromsø, Norway.,Centre of Molecular Inflammation Research, Norwegian University of Science and Technology, Trondheim, Norway
| | - Anne Ma Dyrhol-Riise
- Department of Infectious Diseases, Oslo University Hospital, Ullevaal Hospital, P. O. Box 4956 Nydalen, N-0450, Oslo, Norway.,Institute of Clinical Medicine, University of Oslo, Oslo, Norway.,K.G. Jebsen Inflammatory Research Center, University of Oslo, Oslo, Norway.,Department of Clinical Science, University of Bergen, Bergen, Norway
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12
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Holmberg D, Franzén-Röhl E, Idro R, Opoka RO, Bangirana P, Sellgren CM, Wickström R, Färnert A, Schwieler L, Engberg G, John CC. Cerebrospinal fluid kynurenine and kynurenic acid concentrations are associated with coma duration and long-term neurocognitive impairment in Ugandan children with cerebral malaria. Malar J 2017; 16:303. [PMID: 28754152 PMCID: PMC5534063 DOI: 10.1186/s12936-017-1954-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 07/22/2017] [Indexed: 01/26/2023] Open
Abstract
Background One-fourth of children with cerebral malaria (CM) retain cognitive sequelae up to 2 years after acute disease. The kynurenine pathway of the brain, forming neuroactive metabolites, e.g. the NMDA-receptor antagonist kynurenic acid (KYNA), has been implicated in long-term cognitive dysfunction in other CNS infections. In the present study, the association between the kynurenine pathway and neurologic/cognitive complications in children with CM was investigated. Methods Cerebrospinal fluid (CSF) concentrations of KYNA and its precursor kynurenine in 69 Ugandan children admitted for CM to Mulago Hospital, Kampala, Uganda, between 2008 and 2013 were assessed. CSF kynurenine and KYNA were compared to CSF cytokine levels, acute and long-term neurologic complications, and long-term cognitive impairments. CSF kynurenine and KYNA from eight Swedish children without neurological or infectious disease admitted to Astrid Lindgren’s Children’s Hospital were quantified and used for comparison. Results Children with CM had significantly higher CSF concentration of kynurenine and KYNA than Swedish children (P < 0.0001 for both), and CSF kynurenine and KYNA were positively correlated. In children with CM, CSF kynurenine and KYNA concentrations were associated with coma duration in children of all ages (P = 0.003 and 0.04, respectively), and CSF kynurenine concentrations were associated with worse overall cognition (P = 0.056) and attention (P = 0.003) at 12-month follow-up in children ≥5 years old. Conclusions CSF KYNA and kynurenine are elevated in children with CM, indicating an inhibition of glutamatergic and cholinergic signaling. This inhibition may lead acutely to prolonged coma and long-term to impairment of attention and cognition.
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Affiliation(s)
- Dag Holmberg
- Department of Physiology & Pharmacology, Karolinska Institutet, Stockholm, Sweden.,Department of Medicine Solna, Unit of Infectious Diseases, Karolinska Institutet, Stockholm, Sweden
| | - Elisabeth Franzén-Röhl
- Department of Medicine Solna, Unit of Infectious Diseases, Karolinska Institutet, Stockholm, Sweden.,Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Richard Idro
- Department of Paediatrics and Child Health, Makerere University, Kampala, Uganda
| | - Robert O Opoka
- Department of Paediatrics and Child Health, Makerere University, Kampala, Uganda
| | - Paul Bangirana
- Department of Psychiatry, Makerere University, Kampala, Uganda
| | - Carl M Sellgren
- Department of Physiology & Pharmacology, Karolinska Institutet, Stockholm, Sweden.,Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Ronny Wickström
- Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Anna Färnert
- Department of Medicine Solna, Unit of Infectious Diseases, Karolinska Institutet, Stockholm, Sweden.,Department of Infectious Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Lilly Schwieler
- Department of Physiology & Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Göran Engberg
- Department of Physiology & Pharmacology, Karolinska Institutet, Stockholm, Sweden.
| | - Chandy C John
- Department of Pediatrics, Indiana University, Indianapolis, IN, USA.,Department of Pediatrics, University of Minnesota, Minnesota, USA
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13
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Orhan F, Bhat M, Sandberg K, Ståhl S, Piehl F, Svensson C, Erhardt S, Schwieler L. Tryptophan Metabolism Along the Kynurenine Pathway Downstream of Toll-like Receptor Stimulation in Peripheral Monocytes. Scand J Immunol 2017; 84:262-271. [PMID: 27607184 DOI: 10.1111/sji.12479] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 09/04/2016] [Indexed: 01/19/2023]
Abstract
Tryptophan degradation along the kynurenine pathway is of central importance for the immune function. Toll-like receptors (TLRs), representing the first line of immune defence against pathogens, are expressed in various cell types. The most abundant expression is found on monocytes, macrophages and dendritic cells. The aim of this study was to investigate whether stimulation with different TLR ligands induces the kynurenine pathway in human peripheral monocytes. Cell supernatants were analysed using a liquid chromatography/mass spectrometry to measure kynurenine, kynurenic acid (KYNA), quinolinic acid (QUIN) and tryptophan. Stimulation of TLR-2, TLR-3, TLR-4, TLR-7/8 and TLR-9 was found to induce the production of kynurenine, but only stimulation of TLR-3 increased levels of further downstream metabolites, such as KYNA and QUIN. Stimulation of TLR-1, TLR-5 and TLR-6 did not induce the kynurenine pathway. Taken together, this study provides novel evidence demonstrating that TLR activation induces a pattern of downstream tryptophan degradation along the kynurenine pathway in monocytes. The results of this study may implicate that TLRs can be used as new drug targets for the regulation of aberrant tryptophan metabolism along this pathway, a potential therapeutic strategy that may be of importance in several disorders.
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Affiliation(s)
- F Orhan
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - M Bhat
- Protein Biomarkers, Personalized Healthcare & Biomarker Laboratories, Innovative Medicines, Gothenburg, Sweden
| | - K Sandberg
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.,Department of Medicinal Chemistry, Science for Life Laboratory, Biomedical Center, Uppsala University, Uppsala, Sweden
| | - S Ståhl
- Protein Biomarkers, Personalized Healthcare & Biomarker Laboratories, Innovative Medicines, Gothenburg, Sweden.,Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - F Piehl
- Department of Clinical Neuroscience Centre for Psychiatry Research, Karolinska Institutet, Stockholm, Sweden
| | | | - C Svensson
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - S Erhardt
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - L Schwieler
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
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14
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Brundin L. Reply. Acta Psychiatr Scand 2016; 133:427-8. [PMID: 26750325 DOI: 10.1111/acps.12544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- L Brundin
- Van Andel Research Institute, Grand Rapids, MI, USA.
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15
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Astrocytes as Pharmacological Targets in the Treatment of Schizophrenia. HANDBOOK OF BEHAVIORAL NEUROSCIENCE 2016. [DOI: 10.1016/b978-0-12-800981-9.00025-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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16
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Aeinehband S, Brenner P, Ståhl S, Bhat M, Fidock MD, Khademi M, Olsson T, Engberg G, Jokinen J, Erhardt S, Piehl F. Cerebrospinal fluid kynurenines in multiple sclerosis; relation to disease course and neurocognitive symptoms. Brain Behav Immun 2016; 51:47-55. [PMID: 26189678 DOI: 10.1016/j.bbi.2015.07.016] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2015] [Revised: 06/22/2015] [Accepted: 07/14/2015] [Indexed: 12/14/2022] Open
Abstract
Multiple sclerosis (MS) is a chronic inflammatory and neurodegenerative disease of the central nervous system, with a high rate of neurocognitive symptoms for which the molecular background is still uncertain. There is accumulating evidence for dysregulation of the kynurenine pathway (KP) in different psychiatric and neurodegenerative conditions. We here report the first comprehensive analysis of cerebrospinal fluid (CSF) kynurenine metabolites in MS patients of different disease stages and in relation to neurocognitive symptoms. Levels of tryptophan (TRP), kynurenine (KYN), kynurenic acid (KYNA) and quinolinic acid (QUIN) were determined with liquid chromatography mass spectrometry in cell-free CSF. At the group level MS patients (cohort 1; n=71) did not differ in absolute levels of TRP, KYN, KYNA or QUIN as compared to non-inflammatory neurological disease controls (n=20). Stratification of patients into different disease courses revealed that both absolute QUIN levels and the QUIN/KYN ratio were increased in relapsing-remitting MS (RRMS) patients in relapse. Interestingly, secondary progressive MS (SPMS) displayed a trend for lower TRP and KYNA, while primary progressive (PPMS) patients displayed increased levels of all metabolites, similar to a group of inflammatory neurological disease controls (n=13). In the second cohort (n=48), MS patients with active disease and short disease duration were prospectively evaluated for neuropsychiatric symptoms. In a supervised multivariate analysis using orthogonal projection to latent structures (OPLS-DA) depressed patients displayed higher KYNA/TRP and KYN/TRP ratios, mainly due to low TRP levels. Still, this model had low predictive value and could not completely separate the clinically depressed patients from the non-depressed MS patients. No correlation was evident for other neurocognitive measures. Taken together these results demonstrate that clinical disease activity and differences in disease courses are reflected by changes in KP metabolites. Increased QUIN levels of RRMS patients in relapse and generally decreased levels of TRP in SPMS may relate to neurotoxicity and failure of remyelination, respectively. In contrast, PPMS patients displayed a more divergent pattern more resembling inflammatory conditions such as systemic lupus erythematosus. The pattern of KP metabolites in RRMS patients could not predict neurocognitive symptoms.
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Affiliation(s)
- Shahin Aeinehband
- Department of Clinical Neuroscience, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
| | - Philip Brenner
- Department of Clinical Neuroscience, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Sara Ståhl
- Department of Clinical Neuroscience, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Maria Bhat
- Department of Clinical Neuroscience, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden; AstraZeneca, Research & Development, Innovative Medicines, Personalized Healthcare & Biomarkers, Science for Life Laboratory, Stockholm, Sweden
| | - Mark D Fidock
- AstraZeneca, Research & Development, Innovative Medicines, Personalized Healthcare & Biomarkers, Science for Life Laboratory, Stockholm, Sweden
| | - Mohsen Khademi
- Department of Clinical Neuroscience, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Tomas Olsson
- Department of Clinical Neuroscience, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Göran Engberg
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Jussi Jokinen
- Department of Clinical Neuroscience, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden; Department of Clinical Sciences, Umeå University, Umeå, Sweden
| | - Sophie Erhardt
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Fredrik Piehl
- Department of Clinical Neuroscience, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
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17
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Bay-Richter C, Linderholm KR, Lim CK, Samuelsson M, Träskman-Bendz L, Guillemin GJ, Erhardt S, Brundin L. A role for inflammatory metabolites as modulators of the glutamate N-methyl-D-aspartate receptor in depression and suicidality. Brain Behav Immun 2015; 43:110-7. [PMID: 25124710 DOI: 10.1016/j.bbi.2014.07.012] [Citation(s) in RCA: 203] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 07/16/2014] [Accepted: 07/25/2014] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Patients with depression and suicidality suffer from low-grade neuroinflammation. Pro-inflammatory cytokines activate indoleamine 2,3-dioxygenase, an initial enzyme of the kynurenine pathway. This pathway produces neuroactive metabolites, including quinolinic- and kynurenic acid, binding to the glutamate N-methyl-d-aspartate-receptor, which is hypothesized to be part of the neural mechanisms underlying symptoms of depression. We therefore hypothesized that symptoms of depression and suicidality would fluctuate over time in patients prone to suicidal behavior, depending on the degree of inflammation and kynurenine metabolite levels in the cerebrospinal fluid (CSF). METHODS We measured cytokines and kynurenine metabolites in CSF, collected from suicide attempters at repeated occasions over 2 years (total patient samples n=143, individuals n=30) and healthy controls (n=36). The association between the markers and psychiatric symptoms was assessed using the Montgomery Asberg Depression Rating Scale and the Suicide Assessment Scale. RESULTS Quinolinic acid was increased and kynurenic acid decreased over time in suicidal patients versus healthy controls. Furthermore, we found a significant association between low kynurenic acid and severe depressive symptoms, as well as between high interleukin-6 levels and more severe suicidal symptoms. CONCLUSIONS We demonstrate a long-term dysregulation of the kynurenine pathway in the central nervous system of suicide attempters. An increased load of inflammatory cytokines was coupled to more severe symptoms. We therefore suggest that patients with a dysregulated kynurenine pathway are vulnerable to develop depressive symptoms upon inflammatory conditions, as a result the excess production of the NMDA-receptor agonist quinolinic acid. This study provides a neurobiological framework supporting the use of NMDA-receptor antagonists in the treatment of suicidality and depression.
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Affiliation(s)
- Cecilie Bay-Richter
- Translational Neuropsychiatry Unit, Department of Clinical Medicine, Aarhus University, Risskov, Denmark.
| | - Klas R Linderholm
- Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden
| | - Chai K Lim
- Neuroinflammation Group, Australian School of Advanced Medicine, Macquarie University, NSW, Australia
| | - Martin Samuelsson
- Faculty of Health Sciences, Department of Clinical and Experimental Medicine, Division of Psychiatry, Linköping University, Linköping, Sweden
| | - Lil Träskman-Bendz
- Department of Clinical Sciences, Section of Psychiatry, Lund University, Lund, Sweden
| | - Gilles J Guillemin
- Neuroinflammation Group, Australian School of Advanced Medicine, Macquarie University, NSW, Australia
| | - Sophie Erhardt
- Department of Physiology and Pharmacology, Karolinska Institute, Stockholm, Sweden
| | - Lena Brundin
- Division of Psychiatry and Behavioral Medicine, Michigan State University, Grand Rapids, MI, USA; Laboratory of Behavioral Medicine, Van Andel Research Institute, Grand Rapids, MI, USA
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