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Stone TW, Williams RO. Tryptophan metabolism as a 'reflex' feature of neuroimmune communication: Sensor and effector functions for the indoleamine-2, 3-dioxygenase kynurenine pathway. J Neurochem 2024; 168:3333-3357. [PMID: 38102897 DOI: 10.1111/jnc.16015] [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: 08/08/2023] [Revised: 10/16/2023] [Accepted: 11/08/2023] [Indexed: 12/17/2023]
Abstract
Although the central nervous system (CNS) and immune system were regarded as independent entities, it is now clear that immune system cells can influence the CNS, and neuroglial activity influences the immune system. Despite the many clinical implications for this 'neuroimmune interface', its detailed operation at the molecular level remains unclear. This narrative review focuses on the metabolism of tryptophan along the kynurenine pathway, since its products have critical actions in both the nervous and immune systems, placing it in a unique position to influence neuroimmune communication. In particular, since the kynurenine pathway is activated by pro-inflammatory mediators, it is proposed that physical and psychological stressors are the stimuli of an organismal protective reflex, with kynurenine metabolites as the effector arm co-ordinating protective neural and immune system responses. After a brief review of the neuroimmune interface, the general perception of tryptophan metabolism along the kynurenine pathway is expanded to emphasize this environmentally driven perspective. The initial enzymes in the kynurenine pathway include indoleamine-2,3-dioxygenase (IDO1), which is induced by tissue damage, inflammatory mediators or microbial products, and tryptophan-2,3-dioxygenase (TDO), which is induced by stress-induced glucocorticoids. In the immune system, kynurenic acid modulates leucocyte differentiation, inflammatory balance and immune tolerance by activating aryl hydrocarbon receptors and modulates pain via the GPR35 protein. In the CNS, quinolinic acid activates N-methyl-D-aspartate (NMDA)-sensitive glutamate receptors, whereas kynurenic acid is an antagonist: the balance between glutamate, quinolinic acid and kynurenic acid is a significant regulator of CNS function and plasticity. The concept of kynurenine and its metabolites as mediators of a reflex coordinated protection against stress helps to understand the variety and breadth of their activity. It should also help to understand the pathological origin of some psychiatric and neurodegenerative diseases involving the immune system and CNS, facilitating the development of new pharmacological strategies for treatment.
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Affiliation(s)
- Trevor W Stone
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, UK
| | - Richard O Williams
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, UK
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Kelly DL, Glassman M, Wonodi I, Vyas G, Richardson CM, Nwulia E, Wehring HJ, Oduguwa T, Mackowick M, Hipolito MMS, Peters O, Rai N, Park J, Adebayo AO, Gorelick DA, Weiner E, Liu F, Kearns AM, Adams HA, Love RC, Chen S, Olaniyan A, Ambulos N, McKoy D, Nallani MC, Lanzkron S, Mengistab M, Barr B, Davis E, Lawal R, Buchanan RW, Adebayo R. Clozapine and neutrophil response in patients of African descent: A six-month, multinational, prospective, open-label clinical trial. Schizophr Res 2024; 268:312-322. [PMID: 37633776 PMCID: PMC10891303 DOI: 10.1016/j.schres.2023.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 08/04/2023] [Accepted: 08/05/2023] [Indexed: 08/28/2023]
Abstract
INTRODUCTION Clozapine is the most effective antipsychotic for treatment-resistant schizophrenia, but it is markedly underutilized, particularly in the US Black population, partly because of concern over clozapine-associated low absolute neutrophil count (ANC). People of African descent have a lower normative ANC range than the White population, which is associated with a specific "ACKR1-null" ("Duffy null") CC genotype (SNP rs2814778) on the ACKR1 gene, termed benign ethnic neutropenia (BEN). The range of ANC variability and safety of clozapine have not been established in people with BEN or examined prospectively in people of African descent. METHODS We completed a multisite, 6-month, prospective, open-label clinical trial of clozapine treatment in people of African descent with schizophrenia spectrum disorders for whom clozapine was clinically indicated, with or without the ACKR1-null genotype. We examined clozapine safety and weekly ANC during clozapine treatment and evaluated ANC variability by ACKR1-null genotype, sex, study site, and clozapine dosing using repeated measures analysis of covariance. Genotype was assayed using TaqMan® technology. RESULTS We enrolled 274 participants, of whom 227 (82.8 %) completed 6 months of clozapine treatment. There was one case of severe neutropenia (<500 cells/mm3) (0.36 %) over 1467.6 person-months of clozapine exposure. This participant recovered without sequelae after discontinuation of clozapine. Of the 249 participants with known genotypes, 199 (79.9 %) had the ACKR1-null genotype. Neutropenia (<1500 cells/mm3) occurred significantly more often in the ACKR1-null group (33 % [65/199]) than in those with the T allele (6 % (3/50); p < 0.001). Fourteen (5 %) patients discontinued due to adverse events. Rates of infection and fever were low and sialorrhea was the commonest side effect (N = 187, 68 %). CONCLUSION To our knowledge, this is the largest prospective clozapine trial in people of African descent. Severe neutropenia was rare, despite the high prevalence (80 %) of the ACKR1-null genotype. Our findings suggest that clozapine can be used safely in Black patients including those with BEN.
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Affiliation(s)
- Deanna L Kelly
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, United States of America.
| | - Matthew Glassman
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Ikwunga Wonodi
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, United States of America; Sheppard Pratt Health System, Baltimore, MD, United States of America
| | - Gopal Vyas
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, United States of America; Spring Grove Hospital Center, Catonsville, MD, United States of America
| | - Charles M Richardson
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, United States of America; Spring Grove Hospital Center, Catonsville, MD, United States of America
| | - Evaristus Nwulia
- Howard University Hospital, Washington, DC, United States of America
| | - Heidi J Wehring
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Taiwo Oduguwa
- Federal Neuropsychiatric Hospital Yaba, Lagos, Nigeria
| | - Marie Mackowick
- Clifton T. Perkins Hospital Center, Jessup, MD, United States of America
| | | | | | - Narayan Rai
- Howard University Hospital, Washington, DC, United States of America
| | - Jaeboon Park
- Clifton T. Perkins Hospital Center, Jessup, MD, United States of America
| | | | - David A Gorelick
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Elaine Weiner
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Fang Liu
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Ann Marie Kearns
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Heather A Adams
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, United States of America; Spring Grove Hospital Center, Catonsville, MD, United States of America
| | - Raymond C Love
- University of Maryland School of Pharmacy, Baltimore, MD, United States of America
| | - Shuo Chen
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | | | - Nicholas Ambulos
- University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Darius McKoy
- Howard University Hospital, Washington, DC, United States of America
| | - Madhulika C Nallani
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Sophie Lanzkron
- Johns Hopkins University, Baltimore, MD, United States of America
| | - Mulu Mengistab
- Howard University Hospital, Washington, DC, United States of America
| | - Brian Barr
- University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Erica Davis
- University of Maryland School of Pharmacy, Baltimore, MD, United States of America
| | - Rahman Lawal
- Federal Neuropsychiatric Hospital Yaba, Lagos, Nigeria
| | - Robert W Buchanan
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, United States of America
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Antenucci N, D'Errico G, Fazio F, Nicoletti F, Bruno V, Battaglia G. Changes in kynurenine metabolites in the gray and white matter of the dorsolateral prefrontal cortex of individuals affected by schizophrenia. SCHIZOPHRENIA (HEIDELBERG, GERMANY) 2024; 10:27. [PMID: 38413629 PMCID: PMC10899223 DOI: 10.1038/s41537-024-00447-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 02/02/2024] [Indexed: 02/29/2024]
Abstract
Alterations in the kynurenine pathway of tryptophan metabolism have been implicated in the pathophysiology of schizophrenia. Here, we performed an in-depth analysis of all metabolites of the kynurenine pathway, i.e., tryptophan (TRY), kynurenic acid (KYNA), L-kynurenine (KYN), 3-hydroxykynurenine (3-HK), anthranylic acid (ANA), 3-hydroxyanthranylic acid (3-HANA), xanthurenic acid (XA) and quinolinic acid (QUINA), in postmortem samples of the dorsolateral prefrontal cortex (DLPFC, Brodmann area 46, 9) of individuals affected by schizophrenia and non-schizophrenic controls. The analysis was carried out in the gray and white matter. Levels of KYN, 3-HK, ANA, and 3-HANA were significantly increased in both the gray and white matter of the DLPFC of individuals affected by schizophrenia, whereas levels of TRY, KYNA, and QUINA were increased exclusively in the white matter and remained unchanged in the gray matter. These increases in kynurenine metabolites did not correlate with age, sex, duration of the disease, and duration and type of antipsychotic medication. These findings suggest that the two major branches of the kynurenine pathway, i.e., the transamination of KYN into KYNA, and hydroxylation of KYN into 3-HK are activated in the white matter of individuals affected by schizophrenia, perhaps as a result of neuroinflammation, and support the evidence that abnormalities of the white matter are consistenly associated with schizophrenia.
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Affiliation(s)
- Nico Antenucci
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
- Department of Pharmacology and Neuroscience, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | | | - Francesco Fazio
- IRCCS Neuromed, Pozzilli, Italy
- Department of Psychiatry, University of California San Diego, La Jolla, CA, USA
| | - Ferdinando Nicoletti
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
- IRCCS Neuromed, Pozzilli, Italy
| | - Valeria Bruno
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy.
- IRCCS Neuromed, Pozzilli, Italy.
| | - Giuseppe Battaglia
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
- IRCCS Neuromed, Pozzilli, Italy
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Rust C, Malan-Muller S, van den Heuvel LL, Tonge D, Seedat S, Pretorius E, Hemmings SMJ. Platelets bridging the gap between gut dysbiosis and neuroinflammation in stress-linked disorders: A narrative review. J Neuroimmunol 2023; 382:578155. [PMID: 37523892 DOI: 10.1016/j.jneuroim.2023.578155] [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: 03/20/2023] [Revised: 07/21/2023] [Accepted: 07/23/2023] [Indexed: 08/02/2023]
Abstract
In this narrative review, we examine the association between gut dysbiosis, neuroinflammation, and stress-linked disorders, including depression, anxiety, and post-traumatic stress disorder (PTSD), and investigate whether tryptophan (TRP) metabolism and platelets play a role in this association. The mechanisms underlying the aetiology of stress-linked disorders are complex and not yet completely understood. However, a potential link between chronic inflammation and these disorders may potentially be found in TRP metabolism and platelets. By critically analysing existing literature on platelets, the gut microbiome, and stress-linked disorders, we hope to elicit the role of platelets in mediating the effects on serotonin (5-HT) levels and neuroinflammation. We have included studies specifically investigating platelets and TRP metabolism in relation to inflammation, neuroinflammation and neuropsychiatric disorders. Alteration in microbial composition due to stress could contribute to increased intestinal permeability, facilitating the translocation of microbial products, and triggering the release of pro-inflammatory cytokines. This causes platelets to become hyperactive and secrete 5-HT into the plasma. Increased levels of pro-inflammatory cytokines may also lead to increased permeability of the blood-brain barrier (BBB), allowing inflammatory mediators entry into the brain, affecting the balance of TRP metabolism products, such as 5-HT, kynurenic acid (KYNA), and quinolinic acid (QUIN). These alterations may contribute to neuroinflammation and possible neurological damage. Furthermore, platelets can cross the compromised BBB and interact with astrocytes and neurons, leading to the secretion of 5-HT and pro-inflammatory factors, exacerbating inflammatory conditions in the brain. The mechanisms underlying neuroinflammation resulting from peripheral inflammation are still unclear, but the connection between the brain and gut through the bloodstream could be significant. Identifying peripheral biomarkers and mechanisms in the plasma that reflect neuroinflammation may be important. This review serves as a foundation for further research on the association between the gut microbiome, blood microbiome, and neuropsychiatric disorders. The integration of these findings with protein and metabolite markers in the blood may expand our understanding of the subject.
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Affiliation(s)
- Carlien Rust
- Department of Psychiatry, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa; South African Medical Research Council/Stellenbosch University Genomics of Brain Disorders Unit, Cape Town, South Africa.
| | - Stefanie Malan-Muller
- Department of Pharmacology and Toxicology, Faculty of Medicine, Universidad Complutense de Madrid (UCM), Madrid, Spain; Biomedical Network Research Center of Mental Health (CIBERSAM), Institute of Health Carlos III, Madrid, Spain; Neurochemistry Research Institute UCM, Hospital 12 de Octubre Research Institute (Imas12), Madrid, Spain
| | - Leigh L van den Heuvel
- Department of Psychiatry, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa; South African Medical Research Council/Stellenbosch University Genomics of Brain Disorders Unit, Cape Town, South Africa
| | - Daniel Tonge
- School of Life Sciences, Faculty of Natural Sciences, Keele University, ST5 5BG Newcastle, England, UK
| | - Soraya Seedat
- Department of Psychiatry, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa; South African Medical Research Council/Stellenbosch University Genomics of Brain Disorders Unit, Cape Town, South Africa
| | - Etheresia Pretorius
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch, South Africa; Department of Biochemistry and Systems Biology, Institute of Systems, Molecular and Integrative Biology Biosciences Building, University of Liverpool, Liverpool, United Kingdom.
| | - Sian M J Hemmings
- Department of Psychiatry, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa; South African Medical Research Council/Stellenbosch University Genomics of Brain Disorders Unit, Cape Town, South Africa
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Marszalek-Grabska M, Gawel K, Kosheva N, Kocki T, Turski WA. Developmental Exposure to Kynurenine Affects Zebrafish and Rat Behavior. Cells 2023; 12:2224. [PMID: 37759447 PMCID: PMC10526278 DOI: 10.3390/cells12182224] [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: 08/10/2023] [Accepted: 09/04/2023] [Indexed: 09/29/2023] Open
Abstract
Proper nutrition and supplementation during pregnancy and breastfeeding are crucial for the development of offspring. Kynurenine (KYN) is the central metabolite of the kynurenine pathway and a direct precursor of other metabolites that possess immunoprotective or neuroactive properties, with the ultimate effect on fetal neurodevelopment. To date, no studies have evaluated the effects of KYN on early embryonic development. Thus, the aim of our study was to determine the effect of incubation of larvae with KYN in different developmental periods on the behavior of 5-day-old zebrafish. Additionally, the effects exerted by KYN administered on embryonic days 1-7 (ED 1-7) on the behavior of adult offspring of rats were elucidated. Our study revealed that the incubation with KYN induced changes in zebrafish behavior, especially when zebrafish embryos or larvae were incubated with KYN from 1 to 72 h post-fertilization (hpf) and from 49 to 72 hpf. KYN administered early during pregnancy induced subtle differences in the neurobehavioral development of adult offspring. Further research is required to understand the mechanism of these changes. The larval zebrafish model can be useful for studying disturbances in early brain development processes and their late behavioral consequences. The zebrafish-medium system may be applicable in monitoring drug metabolism in zebrafish.
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Affiliation(s)
- Marta Marszalek-Grabska
- Department of Experimental and Clinical Pharmacology, Medical University, Jaczewskiego 8b, 20-090 Lublin, Poland; (K.G.); (N.K.); (T.K.); (W.A.T.)
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Xue C, Li G, Zheng Q, Gu X, Shi Q, Su Y, Chu Q, Yuan X, Bao Z, Lu J, Li L. Tryptophan metabolism in health and disease. Cell Metab 2023; 35:1304-1326. [PMID: 37352864 DOI: 10.1016/j.cmet.2023.06.004] [Citation(s) in RCA: 98] [Impact Index Per Article: 98.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 04/10/2023] [Accepted: 06/05/2023] [Indexed: 06/25/2023]
Abstract
Tryptophan (Trp) metabolism primarily involves the kynurenine, 5-hydroxytryptamine, and indole pathways. A variety of bioactive compounds produced via Trp metabolism can regulate various physiological functions, including inflammation, metabolism, immune responses, and neurological function. Emerging evidence supports an intimate relationship between Trp metabolism disorder and diseases. The levels or ratios of Trp metabolites are significantly associated with many clinical features. Additionally, studies have shown that disease progression can be controlled by modulating Trp metabolism. Indoleamine-2,3-dioxygenase, Trp-2,3-dioxygenase, kynurenine-3-monooxygenase, and Trp hydroxylase are the rate-limiting enzymes that are critical for Trp metabolism. These key regulatory enzymes can be targeted for treating several diseases, including tumors. These findings provide novel insights into the treatment of diseases. In this review, we have summarized the recent research progress on the role of Trp metabolites in health and disease along with their clinical applications.
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Affiliation(s)
- Chen Xue
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Ganglei Li
- Department of Neurosurgery, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Qiuxian Zheng
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Xinyu Gu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Qingmiao Shi
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Yuanshuai Su
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Qingfei Chu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Xin Yuan
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Zhengyi Bao
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Juan Lu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China.
| | - Lanjuan Li
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China.
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Battaglia MR, Di Fazio C, Battaglia S. Activated Tryptophan-Kynurenine metabolic system in the human brain is associated with learned fear. Front Mol Neurosci 2023; 16:1217090. [PMID: 37575966 PMCID: PMC10416643 DOI: 10.3389/fnmol.2023.1217090] [Citation(s) in RCA: 23] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 07/10/2023] [Indexed: 08/15/2023] Open
Affiliation(s)
- Maria Rita Battaglia
- Istituto di Ricovero e Cura a Carattere Scientifico Azienda Ospedaliero-Universitaria di Bologna, Policlinico S. Orsola, Bologna, Italy
| | - Chiara Di Fazio
- Department of Psychology, Center for Studies and Research in Cognitive Neuroscience, University of Bologna, Bologna, Italy
| | - Simone Battaglia
- Department of Psychology, Center for Studies and Research in Cognitive Neuroscience, University of Bologna, Bologna, Italy
- Department of Psychology, University of Turin, Turin, Italy
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Ciapała K, Pawlik K, Ciechanowska A, Mika J, Rojewska E. Effect of pharmacological modulation of the kynurenine pathway on pain-related behavior and opioid analgesia in a mouse model of neuropathic pain. Toxicol Appl Pharmacol 2023; 461:116382. [PMID: 36681127 DOI: 10.1016/j.taap.2023.116382] [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: 05/01/2022] [Revised: 10/26/2022] [Accepted: 01/14/2023] [Indexed: 01/19/2023]
Abstract
Dysfunction of the central nervous system are accompanied by changes in tryptophan metabolism, with the kynurenine pathway (KP) being the main route of its catabolism. Recently, KP metabolites, which are collectively called kynurenines, have become an area of intense research due to their ability to directly and indirectly affect a variety of classic neurotransmitter systems. However, the significance of KP in neuropathic pain is still poorly understood. Therefore, we designed several experiments to verify changes in the mRNA levels of KP enzymes in parallel with other factors related to this metabolic route after chronic constriction injury of the sciatic nerve (CCI model) in mice. The analysis revealed an increase in, Kmo, Kynu and Haoo mRNA levels in the spinal cord on the 7th day after CCI, while Kat1, Kat2, Tdo2, Ido2 and Qprt mRNA levels remain unchanged. Subsequent pharmacological studies provided evidence that modulation of KP by single intrathecal administration of 1-D-MT, UPF468 or L-kynurenine attenuates mechanical and thermal hypersensitivity and increases the effectiveness of selected opioids in mice as measured on day 7 after CCI. Moreover, our results provide the first evidence that the injection of L-kynurenine preceded by UPF468 (KMO inhibitor) is more effective at reducing hypersensitivity in animals with neuropathic pain. Importantly, L-kynurenine also exerts an analgesic effect after intravenous injections, which is enhanced by the administration of minocycline, an inhibitor of microglial activation. Additionally, L-kynurenine administered intrathecally and intravenously enhances analgesia evoked by all tested opioids (morphine, buprenorphine and oxycodone). Overall, our results indicate that the modulation of KP at different levels might be a new pharmacological tool in neuropathy management.
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Affiliation(s)
- Katarzyna Ciapała
- Maj Institute of Pharmacology, Polish Academy of Sciences, Department of Pain Pharmacology, Krakow, Poland
| | - Katarzyna Pawlik
- Maj Institute of Pharmacology, Polish Academy of Sciences, Department of Pain Pharmacology, Krakow, Poland
| | - Agata Ciechanowska
- Maj Institute of Pharmacology, Polish Academy of Sciences, Department of Pain Pharmacology, Krakow, Poland
| | - Joanna Mika
- Maj Institute of Pharmacology, Polish Academy of Sciences, Department of Pain Pharmacology, Krakow, Poland
| | - Ewelina Rojewska
- Maj Institute of Pharmacology, Polish Academy of Sciences, Department of Pain Pharmacology, Krakow, Poland.
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Hemmer S, Wagmann L, Pulver B, Westphal F, Meyer MR. In Vitro and In Vivo Toxicometabolomics of the Synthetic Cathinone PCYP Studied by Means of LC-HRMS/MS. Metabolites 2022; 12:metabo12121209. [PMID: 36557246 PMCID: PMC9783153 DOI: 10.3390/metabo12121209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 11/25/2022] [Accepted: 11/29/2022] [Indexed: 12/03/2022] Open
Abstract
Synthetic cathinones are one important group amongst new psychoactive substances (NPS) and limited information is available regarding their toxicokinetics and -dynamics. Over the past few years, nontargeted toxicometabolomics has been increasingly used to study compound-related effects of NPS to identify important exogenous and endogenous biomarkers. In this study, the effects of the synthetic cathinone PCYP (2-cyclohexyl-1-phenyl-2-(1-pyrrolidinyl)-ethanone) on in vitro and in vivo metabolomes were investigated. Pooled human-liver microsomes and blood and urine of male Wistar rats were used to generate in vitro and in vivo data, respectively. Samples were analyzed by liquid chromatography and high-resolution mass spectrometry using an untargeted metabolomics workflow. Statistical evaluation was performed using univariate and multivariate statistics. In total, sixteen phase I and one phase II metabolite of PCYP could be identified as exogenous biomarkers. Five endogenous biomarkers (e.g., adenosine and metabolites of tryptophan metabolism) related to PCYP intake could be identified in rat samples. The present data on the exogenous biomarker of PCYP are crucial for setting up analytical screening procedures. The data on the endogenous biomarker are important for further studies to better understand the physiological changes associated with cathinone abuse but may also serve in the future as additional markers for an intake.
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Affiliation(s)
- Selina Hemmer
- Department of Experimental and Clinical Toxicology, Institute of Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University, 66421 Homburg, Germany
| | - Lea Wagmann
- Department of Experimental and Clinical Toxicology, Institute of Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University, 66421 Homburg, Germany
| | - Benedikt Pulver
- State Bureau of Criminal Investigation Schleswig-Holstein, 24116 Kiel, Germany
| | - Folker Westphal
- State Bureau of Criminal Investigation Schleswig-Holstein, 24116 Kiel, Germany
| | - Markus R. Meyer
- Department of Experimental and Clinical Toxicology, Institute of Experimental and Clinical Pharmacology and Toxicology, Center for Molecular Signaling (PZMS), Saarland University, 66421 Homburg, Germany
- Correspondence:
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Stone TW, Clanchy FIL, Huang YS, Chiang NY, Darlington LG, Williams RO. An integrated cytokine and kynurenine network as the basis of neuroimmune communication. Front Neurosci 2022; 16:1002004. [PMID: 36507331 PMCID: PMC9729788 DOI: 10.3389/fnins.2022.1002004] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 10/31/2022] [Indexed: 11/25/2022] Open
Abstract
Two of the molecular families closely associated with mediating communication between the brain and immune system are cytokines and the kynurenine metabolites of tryptophan. Both groups regulate neuron and glial activity in the central nervous system (CNS) and leukocyte function in the immune system, although neither group alone completely explains neuroimmune function, disease occurrence or severity. This essay suggests that the two families perform complementary functions generating an integrated network. The kynurenine pathway determines overall neuronal excitability and plasticity by modulating glutamate receptors and GPR35 activity across the CNS, and regulates general features of immune cell status, surveillance and tolerance which often involves the Aryl Hydrocarbon Receptor (AHR). Equally, cytokines and chemokines define and regulate specific populations of neurons, glia or immune system leukocytes, generating more specific responses within restricted CNS regions or leukocyte populations. In addition, as there is a much larger variety of these compounds, their homing properties enable the superimposition of dynamic variations of cell activity upon local, spatially limited, cell populations. This would in principle allow the targeting of potential treatments to restricted regions of the CNS. The proposed synergistic interface of 'tonic' kynurenine pathway affecting baseline activity and the superimposed 'phasic' cytokine system would constitute an integrated network explaining some features of neuroimmune communication. The concept would broaden the scope for the development of new treatments for disorders involving both the CNS and immune systems, with safer and more effective agents targeted to specific CNS regions.
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Affiliation(s)
- Trevor W. Stone
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, United Kingdom,*Correspondence: Trevor W. Stone,
| | - Felix I. L. Clanchy
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, United Kingdom
| | - Yi-Shu Huang
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, United Kingdom
| | - Nien-Yi Chiang
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, United Kingdom
| | - L. Gail Darlington
- Department of Internal Medicine, Ashtead Hospital, Ashtead, United Kingdom
| | - Richard O. Williams
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, United Kingdom
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11
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Deficiency of kynurenine 3-monooxygenase exacerbates impairment of prepulse inhibition induced by phencyclidine. Biochem Biophys Res Commun 2022; 629:142-151. [PMID: 36116377 DOI: 10.1016/j.bbrc.2022.09.003] [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: 08/30/2022] [Accepted: 09/01/2022] [Indexed: 11/23/2022]
Abstract
Phencyclidine (PCP) causes mental symptoms that closely resemble schizophrenia through the inhibition of the glutamatergic system. The kynurenine (KYN) pathway (KP) generates metabolites that modulate glutamatergic systems such as kynurenic acid (KA), quinolinic acid (QA), and xanthurenic acid (XA). Kynurenine 3-monooxygenase (KMO) metabolizes KYN to 3-hydroxykynurenine (3-HK), an upstream metabolite of QA and XA. Clinical studies have reported lower KMO mRNA and higher KA levels in the postmortem brains of patients with schizophrenia and exacerbation of symptoms in schizophrenia by PCP. However, the association between KMO deficiency and PCP remains elusive. Here, we demonstrated that a non-effective dose of PCP induced impairment of prepulse inhibition (PPI) in KMO KO mice. KA levels were increased in the prefrontal cortex (PFC) and hippocampus (HIP) of KMO KO mice, but 3-HK levels were decreased. In wild-type C57BL/6 N mice, the PPI impairment induced by PCP is exacerbated by KA, while attenuated by 3-HK, QA and XA. Taken together, KMO KO mice were vulnerable to the PPI impairment induced by PCP through an increase in KA and a decrease in 3-HK, suggesting that an increase in the ratio of KA to 3-HK (QA and XA) may play an important role in the pathophysiology of schizophrenia.
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12
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Tryptophan Challenge in Healthy Controls and People with Schizophrenia: Acute Effects on Plasma Levels of Kynurenine, Kynurenic Acid and 5-Hydroxyindoleacetic Acid. Pharmaceuticals (Basel) 2022; 15:ph15081003. [PMID: 36015151 PMCID: PMC9416551 DOI: 10.3390/ph15081003] [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: 07/07/2022] [Revised: 08/01/2022] [Accepted: 08/04/2022] [Indexed: 12/27/2022] Open
Abstract
The pivotal tryptophan (TRP) metabolite kynurenine is converted to several neuroactive compounds, including kynurenic acid (KYNA), which is elevated in the brain and cerebrospinal fluid of people with schizophrenia (SZ) and may contribute to cognitive abnormalities in patients. A small proportion of TRP is metabolized to serotonin and further to 5-hydroxyindoleacetic acid (5-HIAA). Notably, KP metabolism is readily affected by immune stimulation. Here, we assessed the acute effects of an oral TRP challenge (6 g) on peripheral concentrations of kynurenine, KYNA and 5-HIAA, as well as the cytokines interferon-γ, TNF-α and interleukin-6, in 22 participants with SZ and 16 healthy controls (HCs) using a double-blind, placebo-controlled, crossover design. TRP raised the levels of kynurenine, KYNA and 5-HIAA in a time-dependent manner, causing >20-fold, >130-fold and 1.5-fold increases in kynurenine, KYNA and 5-HIAA concentrations, respectively, after 240 min. According to multivariate analyses, neither baseline levels nor the stimulating effects of TRP differed between participants with SZ and HC. Basal cytokine levels did not vary between groups, and remained unaffected by TRP. Although unlikely to be useful diagnostically, measurements of circulating metabolites following an acute TRP challenge may be informative for assessing the in vivo efficacy of drugs that modulate the neosynthesis of KYNA and other products of TRP degradation.
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Sandri BJ, Kim J, Lubach GR, Lock EF, Guerrero C, Higgins L, Markowski TW, Kling PJ, Georgieff MK, Coe CL, Rao RB. Multiomic profiling of iron-deficient infant monkeys reveals alterations in neurologically important biochemicals in serum and cerebrospinal fluid before the onset of anemia. Am J Physiol Regul Integr Comp Physiol 2022; 322:R486-R500. [PMID: 35271351 PMCID: PMC9054343 DOI: 10.1152/ajpregu.00235.2021] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 03/07/2022] [Accepted: 03/08/2022] [Indexed: 12/17/2022]
Abstract
The effects of iron deficiency (ID) during infancy extend beyond the hematologic compartment and include short- and long-term adverse effects on many tissues including the brain. However, sensitive biomarkers of iron-dependent brain health are lacking in humans. To determine whether serum and cerebrospinal fluid (CSF) biomarkers of ID-induced metabolic dysfunction are concordant in the pre/early anemic stage of ID before anemia in a nonhuman primate model of infantile iron deficiency anemia (IDA). ID (n = 7), rhesus infants at 4 mo (pre-anemic period) and 6 mo of age (anemic) were examined. Hematological, metabolomic, and proteomic profiles were generated via HPLC/MS at both time points to discriminate serum biomarkers of ID-induced brain metabolic dysfunction. We identified 227 metabolites and 205 proteins in serum. Abnormalities indicating altered liver function, lipid dysregulation, and increased acute phase reactants were present in ID. In CSF, we measured 210 metabolites and 1,560 proteins with changes in ID infants indicative of metabolomic and proteomic differences indexing disrupted synaptogenesis. Systemic and CSF proteomic and metabolomic changes were present and concurrent in the pre-anemic and anemic periods. Multiomic serum and CSF profiling uncovered pathways disrupted by ID in both the pre-anemic and anemic stages of infantile IDA, including evidence for hepatic dysfunction and activation of acute phase response. Parallel changes observed in serum and CSF potentially provide measurable serum biomarkers of ID that reflect at-risk brain processes prior to progression to clinical anemia.
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Affiliation(s)
- Brian J Sandri
- Division of Neonatology, Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota
- Masonic Institute for the Developing Brain, University of Minnesota, Minneapolis, Minnesota
| | - Jonathan Kim
- Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, Minnesota
| | - Gabriele R Lubach
- Harlow Center for Biological Psychology, University of Wisconsin, Madison, Wisconsin
| | - Eric F Lock
- Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, Minnesota
| | - Candace Guerrero
- Department of Biochemistry, Molecular Biology, & Biophysics, University of Minnesota, Minneapolis, Minnesota
| | - LeeAnn Higgins
- Department of Biochemistry, Molecular Biology, & Biophysics, University of Minnesota, Minneapolis, Minnesota
| | - Todd W Markowski
- Department of Biochemistry, Molecular Biology, & Biophysics, University of Minnesota, Minneapolis, Minnesota
| | - Pamela J Kling
- Division of Neonatology, Department of Pediatrics, University of Wisconsin, Madison, Wisconsin
| | - Michael K Georgieff
- Division of Neonatology, Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota
- Masonic Institute for the Developing Brain, University of Minnesota, Minneapolis, Minnesota
| | - Christopher L Coe
- Harlow Center for Biological Psychology, University of Wisconsin, Madison, Wisconsin
| | - Raghavendra B Rao
- Division of Neonatology, Department of Pediatrics, University of Minnesota, Minneapolis, Minnesota
- Masonic Institute for the Developing Brain, University of Minnesota, Minneapolis, Minnesota
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Sathyasaikumar KV, Pérez de la Cruz V, Pineda B, Vázquez Cervantes GI, Ramírez Ortega D, Donley DW, Severson PL, West BL, Giorgini F, Fox JH, Schwarcz R. Cellular Localization of Kynurenine 3-Monooxygenase in the Brain: Challenging the Dogma. Antioxidants (Basel) 2022; 11:315. [PMID: 35204197 PMCID: PMC8868204 DOI: 10.3390/antiox11020315] [Citation(s) in RCA: 2] [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: 01/13/2022] [Revised: 01/31/2022] [Accepted: 02/02/2022] [Indexed: 02/07/2023] Open
Abstract
Kynurenine 3-monooxygenase (KMO), a key player in the kynurenine pathway (KP) of tryptophan degradation, regulates the synthesis of the neuroactive metabolites 3-hydroxykynurenine (3-HK) and kynurenic acid (KYNA). KMO activity has been implicated in several major brain diseases including Huntington's disease (HD) and schizophrenia. In the brain, KMO is widely believed to be predominantly localized in microglial cells, but verification in vivo has not been provided so far. Here, we examined KP metabolism in the brain after depleting microglial cells pharmacologically with the colony stimulating factor 1 receptor inhibitor PLX5622. Young adult mice were fed PLX5622 for 21 days and were euthanized either on the next day or after receiving normal chow for an additional 21 days. Expression of microglial marker genes was dramatically reduced on day 22 but had fully recovered by day 43. In both groups, PLX5622 treatment failed to affect Kmo expression, KMO activity or tissue levels of 3-HK and KYNA in the brain. In a parallel experiment, PLX5622 treatment also did not reduce KMO activity, 3-HK and KYNA in the brain of R6/2 mice (a model of HD with activated microglia). Finally, using freshly isolated mouse cells ex vivo, we found KMO only in microglia and neurons but not in astrocytes. Taken together, these data unexpectedly revealed that neurons contain a large proportion of functional KMO in the adult mouse brain under both physiological and pathological conditions.
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Affiliation(s)
- Korrapati V. Sathyasaikumar
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD 21228, USA;
| | - Verónica Pérez de la Cruz
- Neurobiochemistry and Behavior Laboratory, National Institute of Neurology and Neurosurgery “Manuel Velasco Suárez”, Mexico City 14269, Mexico; (V.P.d.l.C.); (G.I.V.C.); (D.R.O.)
| | - Benjamín Pineda
- Neuroimmunology Department, National Institute of Neurology and Neurosurgery “Manuel Velasco Suárez”, Mexico City 14269, Mexico;
| | - Gustavo Ignacio Vázquez Cervantes
- Neurobiochemistry and Behavior Laboratory, National Institute of Neurology and Neurosurgery “Manuel Velasco Suárez”, Mexico City 14269, Mexico; (V.P.d.l.C.); (G.I.V.C.); (D.R.O.)
| | - Daniela Ramírez Ortega
- Neurobiochemistry and Behavior Laboratory, National Institute of Neurology and Neurosurgery “Manuel Velasco Suárez”, Mexico City 14269, Mexico; (V.P.d.l.C.); (G.I.V.C.); (D.R.O.)
| | - David W. Donley
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY 82071, USA; (D.W.D.); (J.H.F.)
| | - Paul L. Severson
- Plexxikon Inc., South San Francisco, CA 94080, USA; (P.L.S.); (B.L.W.)
| | - Brian L. West
- Plexxikon Inc., South San Francisco, CA 94080, USA; (P.L.S.); (B.L.W.)
| | - Flaviano Giorgini
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7JA, UK;
| | - Jonathan H. Fox
- Department of Veterinary Sciences, University of Wyoming, Laramie, WY 82071, USA; (D.W.D.); (J.H.F.)
| | - Robert Schwarcz
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD 21228, USA;
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15
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Shilov YE, Baymeeva NV, Brusov OS, Oleichik IV, Sizov SV, Tyurin IA. [Cinnabarinic acid as a potential prognostic marker of schizophrenia]. Zh Nevrol Psikhiatr Im S S Korsakova 2022; 122:138-142. [PMID: 36537644 DOI: 10.17116/jnevro2022122121138] [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: 06/17/2023]
Abstract
OBJECTIVE To develop a method for determining cinnabarinic acid (CA) and its immediate precursor 3-hydroxyanthranylic acid (3HAA) in blood plasma and to study their concentrations in patients with schizophrenia before and after treatment. MATERIAL AND METHODS The study was carried out on a sample of 23 female patients with an attack-like progredient schizophrenia (F20.01). The levels of CA and 3HAA in blood plasma were measured using liquid chromatography with tandem mass spectrometry. RESULTS We found an inverse statistically significant correlation of the sum of CA and 3HAA concentrations before treatment with the total PANSS score after treatment (R=-0.50; p<0.05). There was also an inverse correlation of the CA concentration of before treatment with the total PANSS score after treatment (R=-0.41, p=0.052), statistically significant at the trend level (0.05<p<0.1). CONCLUSION CA concentrations in human blood were determined for the first time. The obtained correlations with clinical data show the potential prognostic significance of determining the levels of CA and 3HAA in blood plasma and increase the relevance of further studies.
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Affiliation(s)
- Yu E Shilov
- Mental Health Research Center, Moscow, Russia
| | | | - O S Brusov
- Mental Health Research Center, Moscow, Russia
| | | | - S V Sizov
- Mental Health Research Center, Moscow, Russia
| | - I A Tyurin
- Sklifosovsky Research Institute of Emergency Medicine of Department of Health of Moscow, Moscow, Russia
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16
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Yang Q, Zhang Y, Yang K, Niu Y, Fan F, Chen S, Luo X, Tan S, Wang Z, Tong J, Yang F, Li CSR, Tan Y. Associations of the serum kynurenine pathway metabolites with P50 auditory gating in non-smoking patients with first-episode schizophrenia. Front Psychiatry 2022; 13:1036421. [PMID: 36339840 PMCID: PMC9632432 DOI: 10.3389/fpsyt.2022.1036421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Accepted: 10/05/2022] [Indexed: 11/21/2022] Open
Abstract
OBJECTIVE Our study aimed to investigate the associations between the serum level of kynurenine pathway (KP) metabolites and P50 auditory gating in non-smoking patients with first-episode schizophrenia (FES). MATERIALS AND METHODS In this study, 82 non-smoking patients with FES and 73 healthy controls (HC). P50 auditory gating was measured using a fully functional digital 64-channel EEG system, and the components included S1 amplitude, S2 amplitude, gating ratio (S2/S1), and amplitude difference (S1-S2). Serum levels of kynurenine and kynurenine acid were assessed using a combination of liquid chromatography with tandem mass spectrometry. Psychopathology was assessed by the Positive and Negative Syndrome Scale (PANSS). RESULTS The serum kynurenine (251.46 ± 65.93 ng/ml vs. 320.65 ± 65.89 ng/ml, t = -6.38, p < 0.001), and kynurenine acid levels (5.19 ± 2.22 ng/ml vs. 13.26 ± 4.23 ng/ml, t = -14.73, p < 0.001), S1 amplitude [2.88 (1.79, 3.78) μV vs. 3.08 (2.46, 4.56) μV, Z = -2.17, p = 0.030] and S1-S2 [1.60 (0.63, 2.49) μV vs. 1.92 (1.12, 2.93) μV, Z = -2.23, p = 0.026] in patients with FES were significantly lower than those in HC. The serum kynurenine and kynurenine acid levels were negatively associated with S1-S2 (r = -0.32, p = 0.004 and r = -0.42, p < 0.001; respectively) and positively correlated with S2/S1 ratio (r = 0.34, p = 0.002 and r = 0.35, p = 0.002; respectively) in patients. CONCLUSION Our findings suggested that neuroactive metabolites of the KP might play an important role in sensory gating deficit in first episode patients with schizophrenia. Furthermore, metabolites of the KP may be a new target for the treatment of cognitive impairments in schizophrenia.
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Affiliation(s)
- Qingyan Yang
- Peking University Huilongguan Clinical Medical School, Beijing Huilongguan Hospital, Beijing, China
| | - Yong Zhang
- Peking University Huilongguan Clinical Medical School, Beijing Huilongguan Hospital, Beijing, China
| | - Kebing Yang
- Peking University Huilongguan Clinical Medical School, Beijing Huilongguan Hospital, Beijing, China
| | - Yajuan Niu
- Peking University Huilongguan Clinical Medical School, Beijing Huilongguan Hospital, Beijing, China
| | - Fengmei Fan
- Peking University Huilongguan Clinical Medical School, Beijing Huilongguan Hospital, Beijing, China
| | - Song Chen
- Peking University Huilongguan Clinical Medical School, Beijing Huilongguan Hospital, Beijing, China
| | - Xingguang Luo
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Shuping Tan
- Peking University Huilongguan Clinical Medical School, Beijing Huilongguan Hospital, Beijing, China
| | - Zhiren Wang
- Peking University Huilongguan Clinical Medical School, Beijing Huilongguan Hospital, Beijing, China
| | - Jinghui Tong
- Peking University Huilongguan Clinical Medical School, Beijing Huilongguan Hospital, Beijing, China
| | - Fude Yang
- Peking University Huilongguan Clinical Medical School, Beijing Huilongguan Hospital, Beijing, China
| | - Chiang-Shan R Li
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States.,Department of Neuroscience, Yale University School of Medicine, New Haven, CT, United States
| | - Yunlong Tan
- Peking University Huilongguan Clinical Medical School, Beijing Huilongguan Hospital, Beijing, China
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Mangge H, Herrmann M, Meinitzer A, Pailer S, Curcic P, Sloup Z, Holter M, Prüller F. Increased Kynurenine Indicates a Fatal Course of COVID-19. Antioxidants (Basel) 2021; 10:1960. [PMID: 34943063 PMCID: PMC8750518 DOI: 10.3390/antiox10121960] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 12/02/2021] [Accepted: 12/06/2021] [Indexed: 12/15/2022] Open
Abstract
(1) Background: An inefficient immune response accompanied by an overwhelming inflammatory reaction is involved in severe courses of COVID-19. Kynurenine (KYN) has important immune-modulatory functions and may contribute to a failure in controlling SARS-CoV-2. The present study aims to explore biomarkers that hint at a fatal outcome of COVID-19 early on. (2) Methods: We established a cohort of 148 hospitalized COVID-19 patients for this study. Thirty-one patients died due to a severe COVID-19 course, and 117 recovered within 90 days. We built a biobank by collecting left-over material from these patients whenever blood arrived at the central laboratory of our University hospital for analysis of routine markers. The scientific laboratory analysis comprised KYN, Tryptophan (TRP), KYN/TRP ratio, ferritin, interleukin-6 (IL-6), C-reactive protein (CRP), creatinine, N-terminal pro-natriuretic peptide (NTproBNP), troponin T (TnT), fibrinogen, D-Dimer, prothrombin time (PT), activated partial thromboplastin time (aPTT), antithrombin (AT), protein C, protein S, factor XIII, lupus aPTT, angiotensin-2, vitamin D metabolites, and telomeres in all COVID-19 patients. Basic clinical characteristics and anteceding diseases including cardiovascular, oncologic, renal, hypertension, pulmonary, metabolic (diabetes, obesity) were recorded in a database together with the laboratory data. (3) Results: At the time of diagnosis of SARS-CoV-2 infection those patients who deceased within 90 days afterwards due to COVID-19, had a significantly higher age, higher KYN, KYN/TRP ratio, ferritin, creatinine, and NTproBNP values than SARS-CoV-2 patients who survived COVID-19 along the same time span. In a Kaplan-Meier analysis the variables age, KYN, ferritin, D-Dimer, TnT, NTproBNP, and creatinine showed a significant influence on survival time. Gender, however, showed no influence. In a combined Cox regression analysis KYN had the highest hazard ratio (1.188, 95% CI: 1.071-1.319) followed by age (1.041, 95% CI: 1.011-1.073). In a ROC analysis, KYN values above the cut off limit of 4.82 nmol/l (as specified by Youden index) had a sensitivity of 82% (95% CI: 66-95%) and a specificity of 72% (95% CI: 65-82%) to predict COVID-19 related death within 90 days observation time. (4) Conclusions: Kynurenine is a promising blood biomarker to predict an increased risk of mortality in SARS-CoV-2 infected people already at the time of the first positive SARS-CoV-2 verification detected in these persons.
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Affiliation(s)
- Harald Mangge
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, 8036 Graz, Austria; (M.H.); (A.M.); (S.P.); (P.C.); (Z.S.); (F.P.)
| | - Markus Herrmann
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, 8036 Graz, Austria; (M.H.); (A.M.); (S.P.); (P.C.); (Z.S.); (F.P.)
| | - Andreas Meinitzer
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, 8036 Graz, Austria; (M.H.); (A.M.); (S.P.); (P.C.); (Z.S.); (F.P.)
| | - Sabine Pailer
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, 8036 Graz, Austria; (M.H.); (A.M.); (S.P.); (P.C.); (Z.S.); (F.P.)
| | - Pero Curcic
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, 8036 Graz, Austria; (M.H.); (A.M.); (S.P.); (P.C.); (Z.S.); (F.P.)
| | - Zdenka Sloup
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, 8036 Graz, Austria; (M.H.); (A.M.); (S.P.); (P.C.); (Z.S.); (F.P.)
| | - Magdalena Holter
- Institute of Medical Informatics, Statistics and Documentation, Medical University of Graz, 8036 Graz, Austria;
| | - Florian Prüller
- Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, 8036 Graz, Austria; (M.H.); (A.M.); (S.P.); (P.C.); (Z.S.); (F.P.)
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Orsatti L, Stiehl T, Dischinger K, Speziale R, Di Pasquale P, Monteagudo E, Müller-Tidow C, Radujkovic A, Dreger P, Luft T. Kynurenine pathway activation and deviation to anthranilic and kynurenic acid in fibrosing chronic graft-versus-host disease. CELL REPORTS MEDICINE 2021; 2:100409. [PMID: 34755129 PMCID: PMC8561165 DOI: 10.1016/j.xcrm.2021.100409] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 10/27/2020] [Accepted: 09/20/2021] [Indexed: 11/18/2022]
Abstract
Fibrosing chronic graft-versus-host disease (cGVHD) is a debilitating complication of allogeneic stem cell transplantation (alloSCT). A driver of fibrosis is the kynurenine (Kyn) pathway, and Kyn metabolism patterns and cytokines may influence cGVHD severity and manifestation (fibrosing versus gastrointestinal [GI] cGVHD). Using a liquid chromatography-tandem mass spectrometry approach on sera obtained from 425 patients with allografts, we identified high CXCL9, high indoleamine-2,3-dioxygenase (IDO) activity, and an activated Kyn pathway as common characteristics in all cGVHD subtypes. Specific Kyn metabolism patterns could be identified for non-severe cGVHD, severe GI cGVHD, and fibrosing cGVHD, respectively. Specifically, fibrosing cGVHD was associated with a distinct pathway shift toward anthranilic and kynurenic acid, correlating with reduced activity of the vitamin-B2-dependent kynurenine monooxygenase, low vitamin B6, and increased interleukin-18. The Kyn metabolite signature is a candidate biomarker for severe fibrosing cGVHD and provides a rationale for translational trials on prophylactic vitamin B2/B6 supplementation for cGVHD prevention. High IDO activity and an activated Kyn pathway are common in all cGVHD subtypes Specific Kyn metabolism patterns were identified for gastrointestinal and fibrosing cGVHD A pathway shift toward anthranilic and kynurenic acid was found in fibrosing cGVHD A rationale for vitamin B2/B6 adjustment for cGVHD prevention is presented
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Affiliation(s)
- Laura Orsatti
- ADME/DMPK Department, IRBM SpA, Pomezia, Rome, Italy
| | - Thomas Stiehl
- Institute for Computational Biomedicine–Disease Modeling, RWTH Aachen University, Aachen, Germany
| | | | | | | | | | | | | | - Peter Dreger
- Department of Medicine V, University of Heidelberg, Heidelberg, Germany
| | - Thomas Luft
- Department of Medicine V, University of Heidelberg, Heidelberg, Germany
- Corresponding author
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19
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Metzner C, Steuber V. The beta component of gamma-band auditory steady-state responses in patients with schizophrenia. Sci Rep 2021; 11:20387. [PMID: 34650135 PMCID: PMC8516862 DOI: 10.1038/s41598-021-99793-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Accepted: 09/24/2021] [Indexed: 01/18/2023] Open
Abstract
The mechanisms underlying circuit dysfunctions in schizophrenia (SCZ) remain poorly understood. Auditory steady-state responses (ASSRs), especially in the gamma and beta band, have been suggested as a potential biomarker for SCZ. While the reduction of 40 Hz power for 40 Hz drive has been well established and replicated in SCZ patients, studies are inconclusive when it comes to an increase in 20 Hz power during 40 Hz drive. There might be several factors explaining the inconsistencies, including differences in the sensitivity of the recording modality (EEG vs MEG), differences in stimuli (click-trains vs amplitude-modulated tones) and large differences in the amplitude of the stimuli. Here, we used a computational model of ASSR deficits in SCZ and explored the effect of three SCZ-associated microcircuit alterations: reduced GABA activity, increased GABA decay times and NMDA receptor hypofunction. We investigated the effect of input strength on gamma (40 Hz) and beta (20 Hz) band power during gamma ASSR stimulation and saw that the pronounced increase in beta power during gamma stimulation seen experimentally could only be reproduced in the model when GABA decay times were increased and only for a specific range of input strengths. More specifically, when the input was in this specific range, the rhythmic drive at 40 Hz produced a strong 40 Hz rhythm in the control network; however, in the 'SCZ-like' network, the prolonged inhibition led to a so-called 'beat-skipping', where the network would only strongly respond to every other input. This mechanism was responsible for the emergence of the pronounced 20 Hz beta peak in the power spectrum. The other two microcircuit alterations were not able to produce a substantial 20 Hz component but they further narrowed the input strength range for which the network produced a beta component when combined with increased GABAergic decay times. Our finding that the beta component only existed for a specific range of input strengths might explain the seemingly inconsistent reporting in experimental studies and suggests that future ASSR studies should systematically explore different amplitudes of their stimuli. Furthermore, we provide a mechanistic link between a microcircuit alteration and an electrophysiological marker in schizophrenia and argue that more complex ASSR stimuli are needed to disentangle the nonlinear interactions of microcircuit alterations. The computational modelling approach put forward here is ideally suited to facilitate the development of such stimuli in a theory-based fashion.
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Affiliation(s)
- Christoph Metzner
- Neural Information Processing Group, Institute of Software Engineering and Theoretical Computer Science, Technische Universität Berlin, Berlin, Germany.
- School of Physics, Engineering and Computer Science, University of Hertfordshire, Hatfield, UK.
| | - Volker Steuber
- School of Physics, Engineering and Computer Science, University of Hertfordshire, Hatfield, UK
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Skorobogatov K, De Picker L, Verkerk R, Coppens V, Leboyer M, Müller N, Morrens M. Brain Versus Blood: A Systematic Review on the Concordance Between Peripheral and Central Kynurenine Pathway Measures in Psychiatric Disorders. Front Immunol 2021; 12:716980. [PMID: 34630391 PMCID: PMC8495160 DOI: 10.3389/fimmu.2021.716980] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 09/08/2021] [Indexed: 12/19/2022] Open
Abstract
Objective Disturbances in the kynurenine pathway have been implicated in the pathophysiology of psychotic and mood disorders, as well as several other psychiatric illnesses. It remains uncertain however to what extent metabolite levels detectable in plasma or serum reflect brain kynurenine metabolism and other disease-specific pathophysiological changes. The primary objective of this systematic review was to investigate the concordance between peripheral and central (CSF or brain tissue) kynurenine metabolites. As secondary aims we describe their correlation with illness course, treatment response, and neuroanatomical abnormalities in psychiatric diseases. Methods We performed a systematic literature search until February 2021 in PubMed. We included 27 original research articles describing a correlation between peripheral and central kynurenine metabolite measures in preclinical studies and human samples from patients suffering from neuropsychiatric disorders and other conditions. We also included 32 articles reporting associations between peripheral KP markers and symptom severity, CNS pathology or treatment response in schizophrenia, bipolar disorder or major depressive disorder. Results For kynurenine and 3-hydroxykynurenine, moderate to strong concordance was found between peripheral and central concentrations not only in psychiatric disorders, but also in other (patho)physiological conditions. Despite discordant findings for other metabolites (mainly tryptophan and kynurenic acid), blood metabolite levels were associated with clinical symptoms and treatment response in psychiatric patients, as well as with observed neuroanatomical abnormalities and glial activity. Conclusion Only kynurenine and 3-hydroxykynurenine demonstrated a consistent and reliable concordance between peripheral and central measures. Evidence from psychiatric studies on kynurenine pathway concordance is scarce, and more research is needed to determine the validity of peripheral kynurenine metabolite assessment as proxy markers for CNS processes. Peripheral kynurenine and 3-hydroxykynurenine may nonetheless represent valuable predictive and prognostic biomarker candidates for psychiatric disorders.
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Affiliation(s)
- Katrien Skorobogatov
- Faculty of Medicine and Health Sciences, Collaborative Antwerp Psychiatric Research Institute (CAPRI), University of Antwerp, Antwerp, Belgium.,Scientific Initiative of Neuropsychiatric and Psychopharmacological Studies (SINAPS), University Psychiatric Centre Duffel, Duffel, Belgium
| | - Livia De Picker
- Faculty of Medicine and Health Sciences, Collaborative Antwerp Psychiatric Research Institute (CAPRI), University of Antwerp, Antwerp, Belgium.,Scientific Initiative of Neuropsychiatric and Psychopharmacological Studies (SINAPS), University Psychiatric Centre Duffel, Duffel, Belgium
| | - Robert Verkerk
- Laboratory of Medical Biochemistry, University of Antwerp, Antwerp, Belgium
| | - Violette Coppens
- Faculty of Medicine and Health Sciences, Collaborative Antwerp Psychiatric Research Institute (CAPRI), University of Antwerp, Antwerp, Belgium.,Scientific Initiative of Neuropsychiatric and Psychopharmacological Studies (SINAPS), University Psychiatric Centre Duffel, Duffel, Belgium
| | - Marion Leboyer
- INSERM U955, Equipe Psychiatrie Translationnelle, Créteil, France.,Fondation FondaMental - Hôpital Albert Chenevier - Pôle Psychiatrie, Créteil, France.,AP-HP, Hôpitaux Universitaires Henri Mondor, DHU Pepsy, Pôle de Psychiatrie et d'Addictologie, Créteil, France.,Université Paris Est Créteil, Faculté de Médecine, Creteil, France
| | - Norbert Müller
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University, München, Germany
| | - Manuel Morrens
- Faculty of Medicine and Health Sciences, Collaborative Antwerp Psychiatric Research Institute (CAPRI), University of Antwerp, Antwerp, Belgium.,Scientific Initiative of Neuropsychiatric and Psychopharmacological Studies (SINAPS), University Psychiatric Centre Duffel, Duffel, Belgium
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21
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Büki A, Kekesi G, Horvath G, Vécsei L. A Potential Interface between the Kynurenine Pathway and Autonomic Imbalance in Schizophrenia. Int J Mol Sci 2021; 22:10016. [PMID: 34576179 PMCID: PMC8467675 DOI: 10.3390/ijms221810016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/08/2021] [Accepted: 09/09/2021] [Indexed: 02/07/2023] Open
Abstract
Schizophrenia is a neuropsychiatric disorder characterized by various symptoms including autonomic imbalance. These disturbances involve almost all autonomic functions and might contribute to poor medication compliance, worsened quality of life and increased mortality. Therefore, it has a great importance to find a potential therapeutic solution to improve the autonomic disturbances. The altered level of kynurenines (e.g., kynurenic acid), as tryptophan metabolites, is almost the most consistently found biochemical abnormality in schizophrenia. Kynurenic acid influences different types of receptors, most of them involved in the pathophysiology of schizophrenia. Only few data suggest that kynurenines might have effects on multiple autonomic functions. Publications so far have discussed the implication of kynurenines and the alteration of the autonomic nervous system in schizophrenia independently from each other. Thus, the coupling between them has not yet been addressed in schizophrenia, although their direct common points, potential interfaces indicate the consideration of their interaction. The present review gathers autonomic disturbances, the impaired kynurenine pathway in schizophrenia, and the effects of kynurenine pathway on autonomic functions. In the last part of the review, the potential interaction between the two systems in schizophrenia, and the possible therapeutic options are discussed.
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Affiliation(s)
- Alexandra Büki
- Department of Physiology, Albert Szent-Györgyi Medical School, University of Szeged, Dóm tér 10., H-6720 Szeged, Hungary; (A.B.); (G.K.); (G.H.)
| | - Gabriella Kekesi
- Department of Physiology, Albert Szent-Györgyi Medical School, University of Szeged, Dóm tér 10., H-6720 Szeged, Hungary; (A.B.); (G.K.); (G.H.)
| | - Gyongyi Horvath
- Department of Physiology, Albert Szent-Györgyi Medical School, University of Szeged, Dóm tér 10., H-6720 Szeged, Hungary; (A.B.); (G.K.); (G.H.)
| | - László Vécsei
- Department of Neurology, Albert Szent-Györgyi Medical School, University of Szeged, Semmelweis u. 6., H-6725 Szeged, Hungary
- MTA-SZTE Neuroscience Research Group, H-6725 Szeged, Hungary
- Interdisciplinary Excellence Center, Department of Neurology, Albert Szent-Györgyi Medical School, University of Szeged, Semmelweis u. 6., H-6725 Szeged, Hungary
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22
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Behl T, Kaur I, Sehgal A, Singh S, Bhatia S, Al-Harrasi A, Zengin G, Bumbu AG, Andronie-Cioara FL, Nechifor AC, Gitea D, Bungau AF, Toma MM, Bungau SG. The Footprint of Kynurenine Pathway in Neurodegeneration: Janus-Faced Role in Parkinson's Disorder and Therapeutic Implications. Int J Mol Sci 2021; 22:6737. [PMID: 34201647 PMCID: PMC8268239 DOI: 10.3390/ijms22136737] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 06/17/2021] [Accepted: 06/21/2021] [Indexed: 02/06/2023] Open
Abstract
Progressive degeneration of neurons and aggravation of dopaminergic neurons in the substantia nigra pars compacta results in the loss of dopamine in the brain of Parkinson's disease (PD) patients. Numerous therapies, exhibiting transient efficacy have been developed; however, they are mostly accompanied by side effects and limited reliability, therefore instigating the need to develop novel optimistic treatment targets. Significant therapeutic targets have been identified, namely: chaperones, protein Abelson, glucocerebrosidase-1, calcium, neuromelanin, ubiquitin-proteasome system, neuroinflammation, mitochondrial dysfunction, and the kynurenine pathway (KP). The role of KP and its metabolites and enzymes in PD, namely quinolinic acid (QUIN), kynurenic acid (KYNA), 3-hydroxykynurenine (3-HK), 3-hydroxyanthranillic acid (3-HAA), kunurenine-3-monooxygenase (KMO), etc. has been reported. The neurotoxic QUIN, N-methyl-D-aspartate (NMDA) receptor agonist, and neuroprotective KYNA-which antagonizes QUIN actions-primarily justify the Janus-faced role of KP in PD. Moreover, KP has been reported to play a biomarker role in PD detection. Therefore, the authors detail the neurotoxic, neuroprotective, and immunomodulatory neuroactive components, alongside the upstream and downstream metabolic pathways of KP, forming a basis for a therapeutic paradigm of the disease while recognizing KP as a potential biomarker in PD, thus facilitating the development of a suitable target in PD management.
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Affiliation(s)
- Tapan Behl
- Department of Pharmacology, Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India; (I.K.); (A.S.); (S.S.)
| | - Ishnoor Kaur
- Department of Pharmacology, Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India; (I.K.); (A.S.); (S.S.)
| | - Aayush Sehgal
- Department of Pharmacology, Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India; (I.K.); (A.S.); (S.S.)
| | - Sukhbir Singh
- Department of Pharmacology, Chitkara College of Pharmacy, Chitkara University, Punjab 140401, India; (I.K.); (A.S.); (S.S.)
| | - Saurabh Bhatia
- Amity Institute of Pharmacy, Amity University, Gurugram, Haryana 122412, India;
- Natural and Medical Sciences Research Centre, University of Nizwa, P.O. Box 33, PC 616 Birkat Al Mouz, Nizwa 611, Oman;
| | - Ahmed Al-Harrasi
- Natural and Medical Sciences Research Centre, University of Nizwa, P.O. Box 33, PC 616 Birkat Al Mouz, Nizwa 611, Oman;
| | - Gokhan Zengin
- Department of Biology, Faculty of Science, Selcuk University Campus, Konya 42130, Turkey;
| | - Adrian Gheorghe Bumbu
- Department of Surgical Disciplines, Faculty of Medicine and Pharmacy, University of Oradea, 410073 Oradea, Romania;
| | - Felicia Liana Andronie-Cioara
- Department of Psycho-Neuroscience and Recovery, Faculty of Medicine and Pharmacy, University of Oradea, 410073 Oradea, Romania;
| | - Aurelia Cristina Nechifor
- Analytical Chemistry and Environmental Engineering Department, Polytechnic University of Bucharest, 011061 Bucharest, Romania;
| | - Daniela Gitea
- Department of Pharmacy, Faculty of Medicine and Pharmacy, University of Oradea, 410028 Oradea, Romania; (D.G.); (M.M.T.)
| | | | - Mirela Marioara Toma
- Department of Pharmacy, Faculty of Medicine and Pharmacy, University of Oradea, 410028 Oradea, Romania; (D.G.); (M.M.T.)
- Doctoral School of Biomedical Sciences, University of Oradea, 410087 Oradea, Romania
| | - Simona Gabriela Bungau
- Department of Pharmacy, Faculty of Medicine and Pharmacy, University of Oradea, 410028 Oradea, Romania; (D.G.); (M.M.T.)
- Doctoral School of Biomedical Sciences, University of Oradea, 410087 Oradea, Romania
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23
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Mithaiwala MN, Santana-Coelho D, Porter GA, O’Connor JC. Neuroinflammation and the Kynurenine Pathway in CNS Disease: Molecular Mechanisms and Therapeutic Implications. Cells 2021; 10:1548. [PMID: 34205235 PMCID: PMC8235708 DOI: 10.3390/cells10061548] [Citation(s) in RCA: 70] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 06/13/2021] [Accepted: 06/15/2021] [Indexed: 12/16/2022] Open
Abstract
Diseases of the central nervous system (CNS) remain a significant health, social and economic problem around the globe. The development of therapeutic strategies for CNS conditions has suffered due to a poor understanding of the underlying pathologies that manifest them. Understanding common etiological origins at the cellular and molecular level is essential to enhance the development of efficacious and targeted treatment options. Over the years, neuroinflammation has been posited as a common link between multiple neurological, neurodegenerative and neuropsychiatric disorders. Processes that precipitate neuroinflammatory conditions including genetics, infections, physical injury and psychosocial factors, like stress and trauma, closely link dysregulation in kynurenine pathway (KP) of tryptophan metabolism as a possible pathophysiological factor that 'fuel the fire' in CNS diseases. In this study, we aim to review emerging evidence that provide mechanistic insights between different CNS disorders, neuroinflammation and the KP. We provide a thorough overview of the different branches of the KP pertinent to CNS disease pathology that have therapeutic implications for the development of selected and efficacious treatment strategies.
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Affiliation(s)
- Mustafa N. Mithaiwala
- Integrated Biomedical Sciences Program, Graduate School of Biomedical Sciences, UT Health San Antonio, San Antonio, TX 78229, USA; (M.N.M.); (D.S.-C.); (G.A.P.)
- Department of Pharmacology, Long School of Medicine, UT Health San Antonio, Mail Code 8864, San Antonio, TX 78229, USA
| | - Danielle Santana-Coelho
- Integrated Biomedical Sciences Program, Graduate School of Biomedical Sciences, UT Health San Antonio, San Antonio, TX 78229, USA; (M.N.M.); (D.S.-C.); (G.A.P.)
- Department of Pharmacology, Long School of Medicine, UT Health San Antonio, Mail Code 8864, San Antonio, TX 78229, USA
| | - Grace A. Porter
- Integrated Biomedical Sciences Program, Graduate School of Biomedical Sciences, UT Health San Antonio, San Antonio, TX 78229, USA; (M.N.M.); (D.S.-C.); (G.A.P.)
- Department of Pharmacology, Long School of Medicine, UT Health San Antonio, Mail Code 8864, San Antonio, TX 78229, USA
| | - Jason C. O’Connor
- Integrated Biomedical Sciences Program, Graduate School of Biomedical Sciences, UT Health San Antonio, San Antonio, TX 78229, USA; (M.N.M.); (D.S.-C.); (G.A.P.)
- Department of Pharmacology, Long School of Medicine, UT Health San Antonio, Mail Code 8864, San Antonio, TX 78229, USA
- Department of Research, Audie L. Murphy VA Hospital, South Texas Veterans Heath System, San Antonio, TX 78229, USA
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24
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Pharmacophore-Based Virtual Screening of Novel Competitive Inhibitors of the Neurodegenerative Disease Target Kynurenine-3-Monooxygenase. Molecules 2021; 26:molecules26113314. [PMID: 34073016 PMCID: PMC8199213 DOI: 10.3390/molecules26113314] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/26/2021] [Accepted: 05/26/2021] [Indexed: 11/27/2022] Open
Abstract
The pathogenesis of several neurodegenerative diseases such as Alzheimer’s or Huntington’s disease has been associated with metabolic dysfunctions caused by imbalances in the brain and cerebral spinal fluid levels of neuroactive metabolites. Kynurenine monooxygenase (KMO) is considered an ideal therapeutic target for the regulation of neuroactive tryptophan metabolites. Despite significant efforts, the known KMO inhibitors lack blood–brain barrier (BBB) permeability and upon the mimicking of the substrate binding mode, are subject to produce reactive oxygen species as a side reaction. The computational drug design is further complicated by the absence of complete crystal structure information for human KMO (hKMO). In the current work, we performed virtual screening of readily available compounds using several protein–ligand complex pharmacophores. Each of the pharmacophores accounts for one of three distinct reported KMO protein-inhibitor binding conformations. As a result, six novel KMO inhibitors were discovered based on an in vitro fluorescence assay. Compounds VS1 and VS6 were predicted to be BBB permeable and avoid the hydrogen peroxide production dilemma, making them valuable, novel hit compounds for further drug property optimization and advancement in the drug design pipeline.
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25
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Rudzki L, Stone TW, Maes M, Misiak B, Samochowiec J, Szulc A. Gut microbiota-derived vitamins - underrated powers of a multipotent ally in psychiatric health and disease. Prog Neuropsychopharmacol Biol Psychiatry 2021; 107:110240. [PMID: 33428888 DOI: 10.1016/j.pnpbp.2020.110240] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 11/19/2020] [Accepted: 12/30/2020] [Indexed: 02/06/2023]
Abstract
Despite the well-established roles of B-vitamins and their deficiencies in health and disease, there is growing evidence indicating a key role of those nutrients in functions of the central nervous system and in psychopathology. Clinical data indicate the substantial role of B-vitamins in various psychiatric disorders, including major depression, bipolar disorder, schizophrenia, autism, and dementia, including Alzheimer's and Parkinson's diseases. As enzymatic cofactors, B-vitamins are involved in many physiological processes such as the metabolism of glucose, fatty acids and amino acids, metabolism of tryptophan in the kynurenine pathway, homocysteine metabolism, synthesis and metabolism of various neurotransmitters and neurohormones including serotonin, dopamine, adrenaline, acetylcholine, GABA, glutamate, D-serine, glycine, histamine and melatonin. Those vitamins are highly involved in brain energetic metabolism and respiration at the cellular level. They have a broad range of anti-inflammatory, immunomodulatory, antioxidant and neuroprotective properties. Furthermore, some of those vitamins are involved in the regulation of permeability of the intestinal and blood-brain barriers. Despite the fact that a substantial amount of the above vitamins is acquired from various dietary sources, deficiencies are not uncommon, and it is estimated that micronutrient deficiencies affect about two billion people worldwide. The majority of gut-resident microbes and the broad range of bacteria available in fermented food, express genetic machinery enabling the synthesis and metabolism of B-vitamins and, consequently, intestinal microbiota and fermented food rich in probiotic bacteria are essential sources of B-vitamins for humans. All in all, there is growing evidence that intestinal bacteria-derived vitamins play a significant role in physiology and that dysregulation of the "microbiota-vitamins frontier" is related to various disorders. In this review, we will discuss the role of vitamins in mental health and explore the perspectives and potential of how gut microbiota-derived vitamins could contribute to mental health and psychiatric treatment.
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Affiliation(s)
- Leszek Rudzki
- The Charleston Centre, 49 Neilston Road, Paisley PA2 6LY, UK.
| | | | - Michael Maes
- Department of Psychiatry, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand; Department of Psychiatry, Medical University of Plovdiv, Bulgaria; IMPACT Strategic Research Center, Deakin University, Geelong, Australia
| | - Błażej Misiak
- Department of Psychiatry, Wroclaw Medical University, Pasteura 10 Street, 50-367 Wroclaw, Poland
| | - Jerzy Samochowiec
- Department of Psychiatry, Pomeranian Medical University, Broniewskiego 26 Street, 71-460 Szczecin, Poland
| | - Agata Szulc
- Department of Psychiatry, Medical University of Warsaw, Poland
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Corsi-Zuelli F, Deakin B. Impaired regulatory T cell control of astroglial overdrive and microglial pruning in schizophrenia. Neurosci Biobehav Rev 2021; 125:637-653. [PMID: 33713699 DOI: 10.1016/j.neubiorev.2021.03.004] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 02/16/2021] [Accepted: 03/06/2021] [Indexed: 02/07/2023]
Abstract
It is widely held that schizophrenia involves an active process of peripheral inflammation that induces or reflects brain inflammation with activation of microglia, the brain's resident immune cells. However, recent in vivo radioligand binding studies and large-scale transcriptomics in post-mortem brain report reduced markers of microglial inflammation. The findings suggest a contrary hypothesis; that microglia are diverted into their non-inflammatory synaptic remodelling phenotype that interferes with neurodevelopment and perhaps contributes to the relapsing nature of schizophrenia. Recent discoveries on the regulatory interactions between micro- and astroglial cells and immune regulatory T cells (Tregs) cohere with clinical omics data to suggest that: i) disinhibited astrocytes mediate the shift in microglial phenotype via the production of transforming growth factor-beta, which also contributes to the disturbances of dopamine and GABA function in schizophrenia, and ii) systemically impaired functioning of Treg cells contributes to the dysregulation of glial function, the low-grade peripheral inflammation, and the hitherto unexplained predisposition to auto-immunity and reduced life-expectancy in schizophrenia, including greater COVID-19 mortality.
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Affiliation(s)
- Fabiana Corsi-Zuelli
- Department of Neuroscience and Behaviour, Division of Psychiatry, Ribeirão Preto Medical School, University of São Paulo, 14048-900, Ribeirão Preto, São Paulo, Brazil
| | - Bill Deakin
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, M13 9PT, UK.
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Więdłocha M, Marcinowicz P, Janoska-Jaździk M, Szulc A. Gut microbiota, kynurenine pathway and mental disorders - Review. Prog Neuropsychopharmacol Biol Psychiatry 2021; 106:110145. [PMID: 33203568 DOI: 10.1016/j.pnpbp.2020.110145] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 10/13/2020] [Accepted: 10/16/2020] [Indexed: 02/08/2023]
Abstract
The intestine and the gut-associated limphoid tissue constitute the largest immunity organ of the human body. Among several possible tryptophan metabolism routes, the kynurenine pathway can be influenced by the gut microbiota. Disturbances of gut biodiversity may cause increased gut permeability and cause systemic inflammation, also related to central nervous system. Proinflammatory cytokines induce kynurenine pathway enzymes resulting in formation of neuroactive metabolites, which are being associated with several psychiatric disorders. The kynurenine pathway may also be influenced by certain bacteria species directly. The aim of this review is to highlight the current knowledge on the interaction of gut microbiota and the central nervous system with the kynurenine pathway taken into special account. Up to date study results on specific psychiatric disorders such as schizophrenia, bipolar disorder, Alzheimer's disease, autism spectrum disorders, depression and alcoholism are presented. Available evidence suggests that toxicity of kynurenine metabolites may be reduced by adjunction of probiotics which can affect proinflammatory cytokines. Due to their potential for modulation of the kynurenine pathway, gut microbiota pose an interesting target for future therapies.
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Affiliation(s)
- Magdalena Więdłocha
- Department of Psychiatry, Faculty of Health Sciences, Medical University of Warsaw, Poland.
| | - Piotr Marcinowicz
- Department of Psychiatry, Faculty of Health Sciences, Medical University of Warsaw, Poland
| | | | - Agata Szulc
- Department of Psychiatry, Faculty of Health Sciences, Medical University of Warsaw, Poland
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28
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Cao B, Chen Y, Ren Z, Pan Z, McIntyre RS, Wang D. Dysregulation of kynurenine pathway and potential dynamic changes of kynurenine in schizophrenia: A systematic review and meta-analysis. Neurosci Biobehav Rev 2021; 123:203-214. [PMID: 33513412 DOI: 10.1016/j.neubiorev.2021.01.018] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 01/19/2021] [Accepted: 01/20/2021] [Indexed: 12/26/2022]
Abstract
The kynurenine (KYN) pathway is postulated to play various roles in immune system dysregulation of schizophrenia (SCZ). We conducted a meta-analysis to explore the association between six key metabolites of KYN pathway (i.e., tryptophan (TRP), KYN, quinolinic acid (QUIN), and kynurenic acid (KYNA)) and SCZ. Priori Bonferroni adjustments were conducted for multiple comparisons. In total, 42 studies that examined the relationship between the metabolites in KYN pathway mentioned above and SCZ in 4217 participants and nine studies that examined alterations of these metabolites after antipsychotic treatments were included. The results demonstrate that (1) subjects with prescribed medication had significantly higher KYN levels when compared to controls; (2) higher KYN levels in cerebrospinal fluid (CSF), lower plasma KYN levels and higher CSF KYNA levels were associated with SCZ; (3) the KYN levels were higher in subjects with SCZ after antipsychotic treatments when compared with baseline. The evidence provides valuable insight of the potential underlying involvement of the KYN pathway in the pathogenesis of SCZ.
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Affiliation(s)
- Bing Cao
- Key Laboratory of Cognition and Personality, Faculty of Psychology, Ministry of Education, Southwest University (SWU), Chongqing, 400715, PR China; National Demonstration Center for Experimental Psychology Education (Southwest University), Chongqing, PR China.
| | - Yan Chen
- Dalla Lana School of Public Health, University of Toronto, 155 College St., Toronto, ON, Canada
| | - Zhongyu Ren
- College of Physical Education, Southwest University, Chongqing, PR China
| | - Zihang Pan
- Duke-NUS Medical School, Singapore, Singapore; Mood Disorders Psychopharmacology Unit, University Health Network, Toronto, Canada
| | - Roger S McIntyre
- Mood Disorders Psychopharmacology Unit, University Health Network, Toronto, Canada; Department of Psychiatry, University of Toronto, Toronto, Canada; Department of Pharmacology, University of Toronto, Toronto, Canada; Brain and Cognition Discovery Foundation, Toronto, ON, Canada
| | - Dongfang Wang
- NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, Chongqing, PR China; Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, PR China.
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29
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Blood-based kynurenine pathway alterations in schizophrenia spectrum disorders: A meta-analysis. Schizophr Res 2020; 223:43-52. [PMID: 32981827 DOI: 10.1016/j.schres.2020.09.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 08/06/2020] [Accepted: 09/14/2020] [Indexed: 02/06/2023]
Abstract
INTRODUCTION The kynurenine pathway (KP) has been proposed as indirect link between systemic immune responses and clinical symptom development in schizophrenia spectrum disorders (SSD). Empirical evidence for such immune-related KP shifts in SSD has however resulted in divergent findings. METHODS We conducted a systematic literature search in PubMed. Thirty papers (total number of patients n = 1506; controls: n = 1432) reported on peripheral concentrations of KP metabolites in SSD patients versus controls. Six KP metabolites were included in a meta-analysis, with secondary analysis of covariate and subgroup effects of patients' symptomatic state, age and duration of illness. RESULTS Tryptophan (SMD: -0.30; p = .003) and Xanthurenic Acid (SMD: -0.80; p < .001) were significantly decreased in SSD compared to controls, while Quinolinic Acid (SMD: -0.40; p = .08) and Kynurenic Acid (SMD: -0.39; p = .04) were only significantly decreased in patients with acute or highly symptomatic illness. Finally, in relatively older patient cohorts Kynurenine (SMD: -0.31; p = .02) and Kynurenic Acid (SMD: -0.40; p = .002) were found to be decreased. CONCLUSION A partial downregulation of the KP is observed in SSD patients, in particular during acute symptomatic states and in older age, effects that were independent from each other. In contrast, younger and stable or remitted patients display limited to no KP metabolite abnormalities. The current meta-analysis illustrates the dynamic nature of KP abnormalities. It should be noted that all included studies investigated peripheral KP metabolites, which do not necessarily reflect central KP metabolite abnormalities in schizophrenic patients.
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Blanco-Ayala T, Sathyasaikumar KV, Uys JD, Pérez-de-la-Cruz V, Pidugu LS, Schwarcz R. N-Acetylcysteine Inhibits Kynurenine Aminotransferase II. Neuroscience 2020; 444:160-169. [PMID: 32768617 DOI: 10.1016/j.neuroscience.2020.07.049] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 07/08/2020] [Accepted: 07/28/2020] [Indexed: 12/22/2022]
Abstract
The tryptophan metabolite kynurenic acid (KYNA) may play an important role in normal and abnormal cognitive processes, most likely by interfering with α7 nicotinic and NMDA receptor function. KYNA is formed from its immediate precursor kynurenine either by non-enzymatic oxidation or through irreversible transamination by kynurenine aminotransferases. In the mammalian brain, kynurenine aminotransferase II (KAT II) is the principal enzyme responsible for the neosynthesis of rapidly mobilizable KYNA, and therefore constitutes an attractive target for pro-cognitive interventions. N-acetylcysteine (NAC), a brain-penetrant drug with pro-cognitive efficacy in humans, has been proposed to exert its actions by increasing the levels of the anti-oxidant glutathione (GSH) in the brain. We report here that NAC, but not GSH, inhibits KAT II activity in brain tissue homogenates from rats and humans with IC50 values in the high micromolar to low millimolar range. With similar potency, the drug interfered with the de novo formation of KYNA in rat brain slices, and NAC was a competitive inhibitor of recombinant human KAT II (Ki: 450 μM). Furthermore, GSH failed to S-glutathionylate recombinant human KAT II treated with the dithiocarbamate drug disulfiram. Shown by microdialysis in the prefrontal cortex of rats treated with kynurenine (50 mg/kg, i.p.), peripheral administration of NAC (500 mg/kg, i.p., 120 and 60 min before the application of kynurenine) reduced KYNA neosynthesis by ∼50%. Together, these results suggest that NAC exerts its neurobiological effects at least in part by reducing cerebral KYNA formation via KAT II inhibition.
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Affiliation(s)
- T Blanco-Ayala
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - K V Sathyasaikumar
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - J D Uys
- Department of Cellular and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, SC, USA
| | - V Pérez-de-la-Cruz
- Laboratorio de Neurobioquimica y Conducta, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, S.S.A. Ciudad de México, Mexico
| | - L S Pidugu
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - R Schwarcz
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA.
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31
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Ulivieri M, Wierońska JM, Lionetto L, Martinello K, Cieslik P, Chocyk A, Curto M, Di Menna L, Iacovelli L, Traficante A, Liberatore F, Mascio G, Antenucci N, Giannino G, Vergassola M, Pittaluga A, Bruno V, Battaglia G, Fucile S, Simmaco M, Nicoletti F, Pilc A, Fazio F. The Trace Kynurenine, Cinnabarinic Acid, Displays Potent Antipsychotic-Like Activity in Mice and Its Levels Are Reduced in the Prefrontal Cortex of Individuals Affected by Schizophrenia. Schizophr Bull 2020; 46:1471-1481. [PMID: 32506121 PMCID: PMC7846105 DOI: 10.1093/schbul/sbaa074] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Cinnabarinic acid (CA) is a kynurenine metabolite that activates mGlu4 metabotropic glutamate receptors. Using a highly sensitive ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS-MS) method, we found that CA is present in trace amounts in human brain tissue. CA levels were largely reduced in the prefrontal cortex (PFC) of individuals affected by schizophrenia. This reduction did not correlate with age, sex, duration of the disease, and duration and type of antipsychotic medication and might, therefore, represent a trait of schizophrenia. Interestingly, systemic treatment with low doses of CA (<1 mg/kg, i.p.) showed robust efficacy in several behavioral tests useful to study antipsychotic-like activity in mice and rats and attenuated MK-801-evoked glutamate release. CA failed to display antipsychotic-like activity and inhibit excitatory synaptic transmission in mice lacking mGlu4 receptors. These findings suggest that CA is a potent endogenous antipsychotic-like molecule and reduced CA levels in the PFC might contribute to the pathophysiology of schizophrenia.
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Affiliation(s)
| | | | - Luana Lionetto
- Department of Medical-Surgical Sciences and Translational Medicine, DiMA (Advanced Molecular Diagnosis), Sant’Andrea Hospital—Sapienza University, Rome, Italy
| | | | - Paulina Cieslik
- Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland
| | - Agnieszka Chocyk
- Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland
| | - Martina Curto
- Department of Neurology and Psychiatry, Sapienza University, Rome, Italy,Department of Clinical and Molecular Medicine, Sapienza University, Rome, Italy,Bipolar & Psychotic Disorders Program, McLean Hospital, Belmont, MA
| | | | - Luisa Iacovelli
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | | | | | | | - Nico Antenucci
- Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | - Giuseppe Giannino
- School of Medicine and Psychology NESMOS Department, Sant’Andrea Hospital, Sapienza University, Rome, Italy
| | | | - Anna Pittaluga
- Department of Pharmacy, DiFAR, University of Genoa, Genoa, Italy,I.R.C.C.S. San Martino Hospital, Genoa, Italy
| | - Valeria Bruno
- I.R.C.C.S. Neuromed, Pozzilli, Italy,Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | - Giuseppe Battaglia
- I.R.C.C.S. Neuromed, Pozzilli, Italy,Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | - Sergio Fucile
- I.R.C.C.S. Neuromed, Pozzilli, Italy,Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | - Maurizio Simmaco
- Department of Medical-Surgical Sciences and Translational Medicine, DiMA (Advanced Molecular Diagnosis), Sant’Andrea Hospital—Sapienza University, Rome, Italy
| | - Ferdinando Nicoletti
- I.R.C.C.S. Neuromed, Pozzilli, Italy,Department of Physiology and Pharmacology, Sapienza University, Rome, Italy
| | - Andrzej Pilc
- Institute of Pharmacology, Polish Academy of Sciences, Kraków, Poland
| | - Francesco Fazio
- I.R.C.C.S. Neuromed, Pozzilli, Italy,To whom correspondence should be addressed; Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Rose F. Kennedy Center, 1410 Pelham Parkway South, room 610, New York City, NY, USA; tel: +1-718-430-2160, fax: +1-718-430-8932, e-mail:
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Discovery of sulfonamides and 9-oxo-2,8-diazaspiro[5,5]undecane-2-carboxamides as human kynurenine aminotransferase 2 (KAT2) inhibitors. Bioorg Med Chem Lett 2020; 30:127060. [PMID: 32113843 DOI: 10.1016/j.bmcl.2020.127060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 02/14/2020] [Accepted: 02/21/2020] [Indexed: 02/02/2023]
Abstract
Human kynurenine aminotransferase 2 (KAT2) inhibitors could be potentially used to treat the cognitive deficits associated with bipolar disease and schizophrenia. Although, there has been active drug research activity by several industrial and academic groups in developing KAT2 inhibitors over the years, no such compound has proceeded to the clinics. Here, we report two different chemical series of reversible KAT2 inhibitors with sub-micromolar activities. The first series was identified by a high-throughput screening of a diverse random library and the second one by structure-based virtual screening. Two novel crystal structures of KAT2 complexed with different reversible inhibitors were also deposited to the Protein databank which could be useful for future drug discovery efforts.
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Metabolomics Adaptation of Juvenile Pacific Abalone Haliotis discus hannai to Heat Stress. Sci Rep 2020; 10:6353. [PMID: 32286374 PMCID: PMC7156721 DOI: 10.1038/s41598-020-63122-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 03/23/2020] [Indexed: 11/13/2022] Open
Abstract
Temperature fluctuation is a key abiotic factor for the growth and survival of Pacific abalone Haliotis discus hannai, particularly during climate change. However, the physiological mechanism underlying the abalones’ response to heat stress remains unknown. We sought to understand the metabolic adaptation mechanism of Pacific abalone to heat stress for further analyzing its heat tolerance capacity. For two groups experienced different acclimate temperature (10 °C and 30 °C for 62 days), the Pacific abalone juveniles displayed significantly different survival rates under 31 °C acute heat treatment. A total of 1815 and 1314 differential metabolites were identified from the 10 °C and 30 °C acclimate groups respectively, by comparing mass spectrometry data of the samples before and after heat stimulation. Heat stress led to mitochondrial failure, resulting in incomplete oxidative metabolism of amino acids and fatty acids in the mitochondria, and massive accumulation of unstable metabolic intermediates in cells. The 10 °C acclimated group accumulated more harmful substances after heat stimulation, provoking further stress responses and pathophysiological processes. In comparison, the 30 °C acclimated group showed stronger regulation capacity to produce beneficial substances for metabolic homeostasis. The findings provided insight into the heat response of marine animals, especially concerning mitochondrial metabolism.
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Meng Q, Ding Y, Chen L, Li L. The medial agranular cortex mediates attentional enhancement of prepulse inhibition of the startle reflex. Behav Brain Res 2020; 383:112511. [DOI: 10.1016/j.bbr.2020.112511] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Revised: 01/15/2020] [Accepted: 01/24/2020] [Indexed: 12/12/2022]
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Huang YS, Ogbechi J, Clanchy FI, Williams RO, Stone TW. IDO and Kynurenine Metabolites in Peripheral and CNS Disorders. Front Immunol 2020; 11:388. [PMID: 32194572 PMCID: PMC7066259 DOI: 10.3389/fimmu.2020.00388] [Citation(s) in RCA: 95] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 02/18/2020] [Indexed: 12/12/2022] Open
Abstract
The importance of the kynurenine pathway in normal immune system function has led to an appreciation of its possible contribution to autoimmune disorders such as rheumatoid arthritis. Indoleamine-2,3-dioxygenase (IDO) activity exerts a protective function, limiting the severity of experimental arthritis, whereas deletion or inhibition exacerbates the symptoms. Other chronic disorder with an inflammatory component, such as atherosclerosis, are also suppressed by IDO activity. It is suggested that this overall anti-inflammatory activity is mediated by a change in the relative production or activity of Th17 and regulatory T cell populations. Kynurenines may play an anti-inflammatory role also in CNS disorders such as Huntington's disease, Alzheimer's disease and multiple sclerosis, in which signs of inflammation and neurodegeneration are involved. The possibility is discussed that in Huntington's disease kynurenines interact with other anti-inflammatory molecules such as Human Lymphocyte Antigen-G which may be relevant in other disorders. Kynurenine involvement may account for the protection afforded to animals with cerebral malaria and trypanosomiasis when they are treated with an inhibitor of kynurenine-3-monoxygenase (KMO). There is some evidence that changes in IL-10 may contribute to this protection and the relationship between kynurenines and IL-10 in arthritis and other inflammatory conditions should be explored. In addition, metabolites of kynurenine downstream of KMO, such as anthranilic acid and 3-hydroxy-anthranilic acid can influence inflammation, and the ratio of these compounds is a valuable biomarker of inflammatory status although the underlying molecular mechanisms of the changes require clarification. Hence it is essential that more effort be expended to identify their sites of action as potential targets for drug development. Finally, we discuss increasing awareness of the epigenetic regulation of IDO, for example by DNA methylation, a phenomenon which may explain differences between individuals in their susceptibility to arthritis and other inflammatory disorders.
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Affiliation(s)
- Yi-Shu Huang
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, United Kingdom
| | - Joy Ogbechi
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, United Kingdom
| | - Felix I Clanchy
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, United Kingdom
| | - Richard O Williams
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, United Kingdom
| | - Trevor W Stone
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, United Kingdom
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Steen NE, Dieset I, Hope S, Vedal TSJ, Smeland OB, Matson W, Kaddurah-Daouk R, Agartz I, Melle I, Djurovic S, Jönsson EG, Bogdanov M, Andreassen OA. Metabolic dysfunctions in the kynurenine pathway, noradrenergic and purine metabolism in schizophrenia and bipolar disorders. Psychol Med 2020; 50:595-606. [PMID: 30867076 DOI: 10.1017/s0033291719000400] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND We aimed at exploring potential pathophysiological processes across psychotic disorders, applying metabolomics in a large and well-characterized sample of patients and healthy controls. METHODS Patients with schizophrenia and bipolar disorders (N = 212) and healthy controls (N = 68) had blood sampling with subsequent metabolomics analyses using electrochemical coulometric array detection. Concentrations of 52 metabolites including tyrosine, tryptophan and purine pathways were compared between patients and controls while controlling for demographic and clinical characteristics. Significant findings were further tested in medication-free subsamples. RESULTS Significantly decreased plasma concentrations in patients compared to healthy controls were found for 3-hydroxykynurenine (3OHKY, p = 0.0008), xanthurenic acid (XANU, p = 1.5×10-5), vanillylmandelic acid (VMA, p = 4.5×10-5) and metanephrine (MN, p = 0.0001). Plasma concentration of xanthine (XAN) was increased in the patient group (p = 3.5×10-5). Differences of 3OHKY, XANU, VMA and XAN were replicated across schizophrenia spectrum disorders and bipolar disorders subsamples of medication-free individuals. CONCLUSIONS Although prone to residual confounding, the present results suggest the kynurenine pathway of tryptophan metabolism, noradrenergic and purinergic system dysfunction as trait factors in schizophrenia spectrum and bipolar disorders. Of special interest is XANU, a metabolite previously not found to be associated with bipolar disorders.
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Affiliation(s)
- Nils Eiel Steen
- NORMENT, KG Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital, and Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Ingrid Dieset
- NORMENT, KG Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital, and Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Sigrun Hope
- NORMENT, KG Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital, and Institute of Clinical Medicine, University of Oslo, Oslo, Norway
- Department of Neurohabilitation, Oslo University Hospital, Oslo, Norway
| | - Trude S J Vedal
- NORMENT, KG Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital, and Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Olav B Smeland
- NORMENT, KG Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital, and Institute of Clinical Medicine, University of Oslo, Oslo, Norway
- Department of Neuroscience, University of California San Diego, La Jolla, CA92093, USA
| | | | - Rima Kaddurah-Daouk
- Duke Molecular Physiology Institute, Duke University, Durham, NC, USA
- Duke Institute of Brain Sciences, Duke University, Durham, NC, USA
- Department of Medicine, Duke University, Durham, NC, USA
| | - Ingrid Agartz
- NORMENT, KG Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital, and Institute of Clinical Medicine, University of Oslo, Oslo, Norway
- Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway
| | - Ingrid Melle
- NORMENT, KG Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital, and Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Srdjan Djurovic
- NORMENT, KG Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital, and Institute of Clinical Medicine, University of Oslo, Oslo, Norway
- Department of Medical Genetics, Oslo University Hospital, Oslo, Norway
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Erik G Jönsson
- NORMENT, KG Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital, and Institute of Clinical Medicine, University of Oslo, Oslo, Norway
- Department of Clinical Neuroscience, Centre for Psychiatric Research, Karolinska Institutet, Stockholm, Sweden
| | | | - Ole A Andreassen
- NORMENT, KG Jebsen Centre for Psychosis Research, Division of Mental Health and Addiction, Oslo University Hospital, and Institute of Clinical Medicine, University of Oslo, Oslo, Norway
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Lu Y, Shao M, Wu T. Kynurenine-3-monooxygenase: A new direction for the treatment in different diseases. Food Sci Nutr 2020; 8:711-719. [PMID: 32148781 PMCID: PMC7020307 DOI: 10.1002/fsn3.1418] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 11/24/2019] [Accepted: 12/21/2019] [Indexed: 12/14/2022] Open
Abstract
Kynurenine-3-monooxygenase (KMO) is an enzyme that relies on nicotinamide adenine dinucleotide phosphate (NADP), a key site in the kynurenine pathway (KP), which has great effects on neurological diseases, cancer, and peripheral inflammation. This review mainly pay attention to the research of KMO mechanism for the treatment of different diseases, and hopes to provide assistance for clinical and drug use. KMO controlling the chief division of the KP, which directly controls downstream product quinolinic acid (QUIN) and indirectly controls kynurenic acid (KYNA), plays an important role in many diseases, especially neurological diseases.
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Affiliation(s)
- Yifei Lu
- Institute of Interdisciplinary Integrative Medicine ResearchShanghai University of Traditional Chinese MedicineShanghaiChina
| | - Mingmei Shao
- Institute of Interdisciplinary Integrative Medicine ResearchShanghai University of Traditional Chinese MedicineShanghaiChina
| | - Tao Wu
- Institute of Interdisciplinary Integrative Medicine ResearchShanghai University of Traditional Chinese MedicineShanghaiChina
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Dysregulation of kynurenine metabolism is related to proinflammatory cytokines, attention, and prefrontal cortex volume in schizophrenia. Mol Psychiatry 2020; 25:2860-2872. [PMID: 30940904 PMCID: PMC7577855 DOI: 10.1038/s41380-019-0401-9] [Citation(s) in RCA: 131] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 02/22/2019] [Accepted: 03/05/2019] [Indexed: 11/09/2022]
Abstract
The kynurenine pathway (KP) of tryptophan (TRP) catabolism links immune system activation with neurotransmitter signaling. The KP metabolite kynurenic acid (KYNA) is increased in the brains of people with schizophrenia. We tested the extent to which: (1) brain KP enzyme mRNAs, (2) brain KP metabolites, and (3) plasma KP metabolites differed on the basis of elevated cytokines in schizophrenia vs. control groups and the extent to which plasma KP metabolites were associated with cognition and brain volume in patients displaying elevated peripheral cytokines. KP enzyme mRNAs and metabolites were assayed in two independent postmortem brain samples from a total of 71 patients with schizophrenia and 72 controls. Plasma KP metabolites, cognition, and brain volumes were measured in an independent cohort of 96 patients with schizophrenia and 81 healthy controls. Groups were stratified based on elevated vs. normal proinflammatory cytokine mRNA levels. In the prefrontal cortex (PFC), kynurenine (KYN)/TRP ratio, KYNA levels, and mRNA for enzymes, tryptophan dioxygenase (TDO) and kynurenine aminotransferases (KATI/II), were significantly increased in the high cytokine schizophrenia subgroup. KAT mRNAs significantly correlated with mRNA for glial fibrillary acidic protein in patients. In plasma, the high cytokine schizophrenia subgroup displayed an elevated KYN/TRP ratio, which correlated inversely with attention and dorsolateral prefrontal cortex (DLPFC) volume. This study provides further evidence for the role of inflammation in a subgroup of patients with schizophrenia and suggests a molecular mechanism through which inflammation could lead to schizophrenia. Proinflammatory cytokines may elicit conversion of TRP to KYN in the periphery and increase the N-methyl-D-aspartate receptor antagonist KYNA via increased KAT mRNA and possibly more enzyme synthesis activity in brain astrocytes, leading to DLPFC volume loss, and attention impairment in schizophrenia.
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The Role of Parvalbumin-positive Interneurons in Auditory Steady-State Response Deficits in Schizophrenia. Sci Rep 2019; 9:18525. [PMID: 31811155 PMCID: PMC6898379 DOI: 10.1038/s41598-019-53682-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Accepted: 10/12/2019] [Indexed: 12/19/2022] Open
Abstract
Despite an increasing body of evidence demonstrating subcellular alterations in parvalbumin-positive (PV+) interneurons in schizophrenia, their functional consequences remain elusive. Since PV+ interneurons are involved in the generation of fast cortical rhythms, these changes have been hypothesized to contribute to well-established alterations of beta and gamma range oscillations in patients suffering from schizophrenia. However, the precise role of these alterations and the role of different subtypes of PV+ interneurons is still unclear. Here we used a computational model of auditory steady-state response (ASSR) deficits in schizophrenia. We investigated the differential effects of decelerated synaptic dynamics, caused by subcellular alterations at two subtypes of PV+ interneurons: basket cells and chandelier cells. Our simulations suggest that subcellular alterations at basket cell synapses rather than chandelier cell synapses are the main contributor to these deficits. Particularly, basket cells might serve as target for innovative therapeutic interventions aiming at reversing the oscillatory deficits.
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Boros FA, Vécsei L. Immunomodulatory Effects of Genetic Alterations Affecting the Kynurenine Pathway. Front Immunol 2019; 10:2570. [PMID: 31781097 PMCID: PMC6851023 DOI: 10.3389/fimmu.2019.02570] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 10/16/2019] [Indexed: 12/15/2022] Open
Abstract
Several enzymes and metabolites of the kynurenine pathway (KP) have immunomodulatory effects. Modulation of the activities and levels of these molecules might be of particular importance under disease conditions when the amelioration of overreacting immune responses is desired. Results obtained by the use of animal and tissue culture models indicate that by eliminating or decreasing activities of key enzymes of the KP, a beneficial shift in disease outcome can be attained. This review summarizes experimental data of models in which IDO, TDO, or KMO activity modulation was achieved by interventions affecting enzyme production at a genomic level. Elimination of IDO activity was found to improve the outcome of sepsis, certain viral infections, chronic inflammation linked to diabetes, obesity, aorta aneurysm formation, and in anti-tumoral processes. Similarly, lack of TDO activity was advantageous in the case of anti-tumoral immunity, while KMO inhibition was found to be beneficial against microorganisms and in the combat against tumors, as well. On the other hand, the complex interplay among KP metabolites and immune function in some cases requires an increase in a particular enzyme activity for the desired immune response modulation, as was shown by the exacerbation of liver fibrosis due to the elimination of IDO activity and the detrimental effects of TDO inhibition in a mouse model of autoimmune gastritis. The relevance of these studies concerning possible human applications are discussed and highlighted. Finally, a brief overview is presented on naturally occurring genetic variants affecting immune functions via modulation of KP enzyme activity.
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Affiliation(s)
- Fanni A. Boros
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary
| | - László Vécsei
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary
- MTA-SZTE Neuroscience Research Group of the Hungarian Academy of Sciences, University of Szeged, Szeged, Hungary
- Department of Neurology, Interdisciplinary Excellence Centre, University of Szeged, Szeged, Hungary
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Harper MM, Woll AW, Evans LP, Delcau M, Akurathi A, Hedberg-Buenz A, Soukup DA, Boehme N, Hefti MM, Dutca LM, Anderson MG, Bassuk AG. Blast Preconditioning Protects Retinal Ganglion Cells and Reveals Targets for Prevention of Neurodegeneration Following Blast-Mediated Traumatic Brian Injury. Invest Ophthalmol Vis Sci 2019; 60:4159-4170. [PMID: 31598627 PMCID: PMC6785841 DOI: 10.1167/iovs.19-27565] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 08/22/2019] [Indexed: 12/13/2022] Open
Abstract
Purpose The purpose of this study was to examine the effect of multiple blast exposures and blast preconditioning on the structure and function of retinal ganglion cells (RGCs), to identify molecular pathways that contribute to RGC loss, and to evaluate the role of kynurenine-3-monooxygenase (KMO) inhibition on RGC structure and function. Methods Mice were subjected to sham blast injury, one single blast injury, or three blast injuries separated by either 1 hour or 1 week, using a blast intensity of 20 PSI. To examine the effect of blast preconditioning, mice were subjected to sham blast injury, one single 20-PSI injury, or three blast injuries separated by 1 week (5 PSI, 5 PSI, 20 PSI and 5 PSI, 5 PSI, 5 PSI). RGC structure was analyzed by optical coherence tomography (OCT) and function was analyzed by the pattern electroretinogram (PERG). BRN3A-positive cells were quantified to determine RGC density. RNA-seq analysis was used to identify transcriptional changes between groups. Results Analysis of mice with multiple blast exposures of 20 PSI revealed no significant differences compared to one 20-pounds per square inch (PSI) exposure using OCT, PERG, or BRN3A cell counts. Analysis of mice exposed to two preconditioning 5-PSI blasts prior to one 20-PSI blast showed preservation of RGC structure and function. RNA-seq analysis of the retina identified multiple transcriptomic changes between conditions. Pharmacologic inhibition of KMO preserved RGC responses compared to vehicle-treated mice. Conclusions Preconditioning protects RGC from blast injury. Protective effects appear to involve changes in KMO activity, whose inhibition is also protective.
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Affiliation(s)
- Matthew M. Harper
- The Iowa City Department of Veterans Affairs Medical Center, Center for the Prevention and Treatment of Visual Loss, Iowa City, Iowa
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa, United States
| | - Addison W. Woll
- The Iowa City Department of Veterans Affairs Medical Center, Center for the Prevention and Treatment of Visual Loss, Iowa City, Iowa
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa, United States
| | - Lucy P. Evans
- Medical Scientist Training Program, University of Iowa, Iowa City, Iowa, United States
- Department of Pediatrics, University of Iowa, Iowa City, Iowa, United States
| | - Michael Delcau
- The Iowa City Department of Veterans Affairs Medical Center, Center for the Prevention and Treatment of Visual Loss, Iowa City, Iowa
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa, United States
| | - Abhigna Akurathi
- The Iowa City Department of Veterans Affairs Medical Center, Center for the Prevention and Treatment of Visual Loss, Iowa City, Iowa
| | - Adam Hedberg-Buenz
- The Iowa City Department of Veterans Affairs Medical Center, Center for the Prevention and Treatment of Visual Loss, Iowa City, Iowa
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa, United States
| | - Dana A. Soukup
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa, United States
| | - Nickolas Boehme
- The Iowa City Department of Veterans Affairs Medical Center, Center for the Prevention and Treatment of Visual Loss, Iowa City, Iowa
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa, United States
| | - Marco M. Hefti
- Department of Pathology, University of Iowa, Iowa City, Iowa, United States
| | - Laura M. Dutca
- The Iowa City Department of Veterans Affairs Medical Center, Center for the Prevention and Treatment of Visual Loss, Iowa City, Iowa
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa, United States
| | - Michael G. Anderson
- The Iowa City Department of Veterans Affairs Medical Center, Center for the Prevention and Treatment of Visual Loss, Iowa City, Iowa
- Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa, United States
- Department of Molecular Physiology and Biophysics, University of Iowa, Iowa City, Iowa, United States
| | - Alexander G. Bassuk
- Department of Pediatrics, University of Iowa, Iowa City, Iowa, United States
- Department of Neurology, University of Iowa, Iowa City, Iowa, United States
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Solvang SEH, Nordrehaug JE, Aarsland D, Lange J, Ueland PM, McCann A, Midttun Ø, Tell GS, Giil LM. Kynurenines, Neuropsychiatric Symptoms, and Cognitive Prognosis in Patients with Mild Dementia. Int J Tryptophan Res 2019; 12:1178646919877883. [PMID: 31632053 PMCID: PMC6769202 DOI: 10.1177/1178646919877883] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 08/31/2019] [Indexed: 01/13/2023] Open
Abstract
Introduction: Circulating tryptophan (Trp) and its downstream metabolites, the kynurenines,
are potentially neuroactive. Consequently, they could be associated with
neuropsychiatric symptoms and cognitive prognosis in patients with
dementia. Objective: The objective of this study was to assess associations between circulating
kynurenines, cognitive prognosis, and neuropsychiatric symptoms. Methods: We measured baseline serum Trp, neopterin, pyridoxal 5′-phosphate (PLP), and
9 kynurenines in 155 patients with mild dementia (90 with Alzheimer’s
disease, 65 with Lewy body dementia). The ratios between kynurenine and Trp
and kynurenic acid (KA) to kynurenine (KKR) were calculated. The Mini-Mental
State Examination (MMSE) and the Neuropsychiatric Inventory (NPI) were
administered at baseline and annually over 5 years. Associations between
baseline metabolite concentrations with MMSE and the NPI total score were
assessed using a generalized structural equation model (mixed-effects
multiprocess model), adjusted for age, sex, current smoking, glomerular
filtration rate, and PLP. Post hoc associations between KKRs and individual
NPI items were assessed using logistic mixed-effects models. False discovery
rate (0.05)–adjusted P values (Q values)
are reported. Results: Kynurenine had a nonlinear quadratic relationship with the intercept of the
MMSE scores over 5 years (Q < 0.05), but not with the
slope of MMSE decline. Kynurenine was associated with a higher NPI total
score over time (Q < 0.001). Post hoc, both KKR and KA
were associated with more hallucinations (Q < 0.05). Conclusions: Kynurenine has a complex relationship with cognition, where both low and high
levels were associated with poor cognitive performance. A higher KKR
indicated risk for neuropsychiatric symptoms, especially hallucinations.
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Affiliation(s)
- Stein-Erik Hafstad Solvang
- Department of Internal Medicine, Haraldsplass Deaconess Hospital, Bergen, Norway.,Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Jan Erik Nordrehaug
- Department of Internal Medicine, Haraldsplass Deaconess Hospital, Bergen, Norway.,Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Dag Aarsland
- Department of Old Age Psychiatry, King's College University, London, UK
| | - Johannes Lange
- The Norwegian Centre for Movement Disorders, Stavanger University Hospital, Stavanger, Norway.,Centre for Organelle Research (CORE), University of Stavanger, Stavanger, Norway
| | | | | | | | - Grethe S Tell
- Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway.,Division of Mental and Physical Health, Norwegian Institute of Public Health, Bergen, Norway
| | - Lasse Melvaer Giil
- Department of Internal Medicine, Haraldsplass Deaconess Hospital, Bergen, Norway.,Department of Clinical Science, University of Bergen, Bergen, Norway
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Badawy AAB, Guillemin G. The Plasma [Kynurenine]/[Tryptophan] Ratio and Indoleamine 2,3-Dioxygenase: Time for Appraisal. Int J Tryptophan Res 2019; 12:1178646919868978. [PMID: 31488951 PMCID: PMC6710706 DOI: 10.1177/1178646919868978] [Citation(s) in RCA: 128] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 07/19/2019] [Indexed: 12/01/2022] Open
Abstract
The plasma kynurenine to tryptophan ([Kyn]/[Trp]) ratio is frequently used to express or reflect the activity of the extrahepatic Trp-degrading enzyme indoleamine 2,3-dioxygenase (IDO). This ratio is increasingly used instead of measurement of IDO activity, which is often low or undetectable in immune and other cells under basal conditions, but is greatly enhanced after immune activation. The use of this ratio is valid in in vitro studies, eg, in cell cultures or isolated organs, but its ‘blanket’ use in in vivo situations is not, because of modulating factors, such as supply of nutrients; the presence of multiple cell types; complex structural and functional tissue arrangements; the extracellular matrix; and hormonal, cytokine, and paracrine interactions. Determinants other than IDO may therefore be involved in vivo. These are hepatic tryptophan 2,3-dioxygenase (TDO) activity and the flux of plasma-free Trp down the Kyn pathway. In addition, conditions leading to accumulation of Kyn, eg, inhibition of activities of Kyn monooxygenase and kynureninase, could lead to elevation of the aforementioned ratio. In this review, the origin of use of this ratio will be discussed, variations in extent of its elevation will be described, evidence against its indiscriminate use will be presented, and examining determinants other than IDO activity and their correlates will be proposed for future studies.
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Affiliation(s)
| | - Gilles Guillemin
- Centre for MND Research, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
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45
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Abstract
Approximately 20%-30% of schizophrenia patients are resistant to current standard pharmacotherapies. Recent schizophrenia research aims to identify specific pathophysiological abnormalities and novel targets in the disease, with the goals of identifying at-risk individuals, facilitating diagnosis, prompting early and personalized interventions, and helping predict response to treatment. Metabolomics involves the systematic study of the profile of biochemical alterations early in the course of a given disorder. Major aspects of the schizophrenia metabolome have been characterized, uncovering potential selective biomarkers for the disease that may change how the disorder is diagnosed, and how patients are stratified and treated. This review focuses on the most common metabolomic fingerprints of the different pathways involved in the pathophysiology of schizophrenia, and the potential development of novel metabolomic-related pharmacotherapies for improved treatment of schizophrenia and other related idiopathic psychotic disorders.
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Rudzki L, Ostrowska L, Pawlak D, Małus A, Pawlak K, Waszkiewicz N, Szulc A. Probiotic Lactobacillus Plantarum 299v decreases kynurenine concentration and improves cognitive functions in patients with major depression: A double-blind, randomized, placebo controlled study. Psychoneuroendocrinology 2019; 100:213-222. [PMID: 30388595 DOI: 10.1016/j.psyneuen.2018.10.010] [Citation(s) in RCA: 269] [Impact Index Per Article: 53.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 10/13/2018] [Accepted: 10/14/2018] [Indexed: 12/19/2022]
Abstract
BACKGROUND Interactions between the digestive system and the brain functions have become in recent years an important field of psychiatric research. These multidirectional interactions take place in the so called microbiota-gut-brain axis and emerging scientific data indicate to the significant role of microbiota in the modulation of the central nervous system (CNS) including affective and cognitive functions. OBJECTIVE An assessment of psychobiotic and immunomodulatory effects of probiotic bacteria Lactobacillus Plantarum 299v (LP299v) by measuring affective, cognitive functions and biochemical parameters in patients with MDD undergoing treatment with selective serotonin reuptake inhibitors (SSRI). DESIGN Seventy nine patients with MDD were randomized and allocated to a double-blind, placebo-controlled trial. Participants received either a SSRI with the probiotic LP299v (n = 40) for a period of 8 weeks or a SSRI with the placebo of the probiotic (n = 39) for the same period. The severity of psychiatric symptoms was assessed using Hamilton Depression Rating Scale (HAM-D 17), Symptom Checklist (SCL-90) and Perceived Stress Scale (PSS-10). Cognitive functions were assessed using the Attention and Perceptivity Test (APT), Stroop Test parts A and B, Ruff Figural Fluency Test (RFFT), Trail Making Test (TMT) Parts A and B and the California Verbal Learning Test (CVLT). Biochemical parameters such as tryptophan (TRP), kynurenine (KYN), kynurenic acid (KYNA), 3-hydroxykynurenine (3HKYN), anthranilic acid (AA), 3-hydroxy anthranilic acid (3HAA), tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), interleukin 1-beta (IL-1b) and cortisol plasma concentrations were measured. RESULTS Sixty participants finished the study and were analyzed: 30 participants in the LP299v group and 30 participants in the placebo group. There was an improvement in APT and in CVLT total recall of trials 1-5 in the LP299v group compared with the placebo between baseline and after 8 weeks of intervention. There was a significant decrease in KYN concentration in the LP299v group compared to the placebo group. We also observed significant increase in 3HKYN:KYN ratio in the LP299v group compared with the placebo group. Additionally, Repeated Measures ANOVA revealed a significant effect of interaction of Treatment x time for AA concentration. However, results of post hoc analysis did not reach statistical significance in neither probiotic nor placebo group. There were no significant changes of TNF-α, IL-6 and IL-1b and cortisol concentrations in neither probiotic nor placebo groups. CONCLUSIONS Augmentation of SSRI treatment with probiotic bacteria Lactobacillus Plantarum 299v improved cognitive performance and decreased KYN concentration in MDD patients. Decreased KYN concentration could contribute to the improvement of cognitive functions in the LP299v group compared to the placebo group. To our knowledge results of this study are the first evidence of improvement of cognitive functions in MDD patients due to probiotic bacteria and this is the first evidence of decreased KYN concentration in MDD patients due to probiotic bacteria.
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Affiliation(s)
- Leszek Rudzki
- Department of Psychiatry, Medical University of Bialystok, Poland.
| | - Lucyna Ostrowska
- Department of Dietetics and Clinical Nutrition, Medical University of Bialystok, Poland.
| | - Dariusz Pawlak
- Department of Pharmacodynamics, Medical University of Bialystok, Poland.
| | - Aleksandra Małus
- Department of Psychiatry, Medical University of Bialystok, Poland.
| | - Krystyna Pawlak
- Department of Monitored Pharmacotherapy, Medical University of Bialystok, Poland.
| | | | - Agata Szulc
- Department of Psychiatry, Medical University of Warsaw, Poland.
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Nicoletti F, Orlando R, Di Menna L, Cannella M, Notartomaso S, Mascio G, Iacovelli L, Matrisciano F, Fazio F, Caraci F, Copani A, Battaglia G, Bruno V. Targeting mGlu Receptors for Optimization of Antipsychotic Activity and Disease-Modifying Effect in Schizophrenia. Front Psychiatry 2019; 10:49. [PMID: 30890967 PMCID: PMC6413697 DOI: 10.3389/fpsyt.2019.00049] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 01/23/2019] [Indexed: 01/03/2023] Open
Abstract
Metabotropic glutamate (mGlu) receptors are considered as candidate drug targets for the treatment of schizophrenia. These receptors form a family of eight subtypes (mGlu1 to -8), of which mGlu1 and -5 are coupled to Gq/11, and all other subtypes are coupled to Gi/o. Here, we discuss the possibility that selective ligands of individual mGlu receptor subtypes may be effective in controlling the core symptoms of schizophrenia, and, in some cases, may impact mechanisms underlying the progression of the disorder. Recent evidence indicates that activation of mGlu1 receptors inhibits dopamine release in the meso-striatal system. Hence, selective positive allosteric modulators (PAMs) of mGlu1 receptors hold promise for the treatment of positive symptoms of schizophrenia. mGlu5 receptors are widely expressed in the CNS and regulate the activity of cells that are involved in the pathophysiology of schizophrenia, such as cortical GABAergic interneurons and microglial cells. mGlu5 receptor PAMs are under development for the treatment of schizophrenia and cater the potential to act as disease modifiers by restraining neuroinflammation. mGlu2 receptors have attracted considerable interest because they negatively modulate 5-HT2A serotonin receptor signaling in the cerebral cortex. Both mGlu2 receptor PAMs and orthosteric mGlu2/3 receptor agonists display antipsychotic-like activity in animal models, and the latter drugs are inactive in mice lacking mGlu2 receptors. So far, mGlu3 receptors have been left apart as drug targets for schizophrenia. However, activation of mGlu3 receptors boosts mGlu5 receptor signaling, supports neuronal survival, and drives microglial cells toward an antiinflammatory phenotype. This strongly encourages research of mGlu3 receptors in schizophrenia. Finally, preclical studies suggest that mGlu4 receptors might be targeted by novel antipsychotic drugs, whereas studies of mGlu7 and mGlu8 receptors in animal models of psychosis are still at their infancy.
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Affiliation(s)
- Ferdinando Nicoletti
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy.,IRCCS Neuromed, Pozzilli, Italy
| | - Rosamaria Orlando
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | | | | | | | | | - Luisa Iacovelli
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Francesco Matrisciano
- Department of Psychiatry, The Psychiatric Institute, College of Medicine, University of Illinois, Chicago, IL, United States
| | | | - Filippo Caraci
- Department of Drug Sciences, University of Catania, Catania, Italy.,Oasi Research Institute (IRCCS), Troina, Italy
| | - Agata Copani
- Department of Drug Sciences, University of Catania, Catania, Italy.,Institute of Biostructure and Bioimaging, National Research Council, Catania, Italy
| | | | - Valeria Bruno
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy.,IRCCS Neuromed, Pozzilli, Italy
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Qin Y, Wang N, Zhang X, Han X, Zhai X, Lu Y. IDO and TDO as a potential therapeutic target in different types of depression. Metab Brain Dis 2018; 33:1787-1800. [PMID: 30014175 DOI: 10.1007/s11011-018-0290-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 07/10/2018] [Indexed: 12/20/2022]
Abstract
Depression is highly prevalent worldwide and a leading cause of disabilty. However, the medications currently available to treat depression fail to adequately relieve depressive symptoms for a large number of patients. Research into the aberrant overactivation of the kynurenine pathway and the production of various active metabolites has brought new insight into the progression of depression. IDO and TDO are the first and rate-limiting enzymes in the kynurenine pathway and regulate the production of active metabolites. There is substantial evidence that TDO and IDO enzyme are activated during depression, and therefore, IDO and TDO inhibitors have been identified as ideal therapeutic targets for depressive disorder. Hence, this review will focus on the kynurenine branch of tryptophan metabolism and describe the role of IDO and TDO in the pathology of depression. In addition, this review will compare the relative imbalance between KYNA and neurotoxic kynurenine metabolites in different psychiatric disorders. Finally, this review is also directed toward assessing whether IDO and TDO are potential therapeutic target in depression associated with other diseases such as diabetes and/or cancer, as well as the development of potent IDO and TDO inhibitors.
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Affiliation(s)
- Yanjie Qin
- Department of Pharmacy, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Nanxi Wang
- Department of Pharmacy, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Xinlin Zhang
- Department of Pharmacy, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Xuemei Han
- Department of Pharmacy, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Xuejia Zhai
- Department of Pharmacy, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
| | - Yongning Lu
- Department of Pharmacy, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
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49
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Beggiato S, Notarangelo FM, Sathyasaikumar KV, Giorgini F, Schwarcz R. Maternal genotype determines kynurenic acid levels in the fetal brain: Implications for the pathophysiology of schizophrenia. J Psychopharmacol 2018; 32:1223-1232. [PMID: 30354938 DOI: 10.1177/0269881118805492] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND Several studies suggest a pathophysiologically relevant association between increased brain levels of the neuroinhibitory tryptophan metabolite kynurenic acid and cognitive dysfunctions in people with schizophrenia. Elevated kynurenic acid in schizophrenia may be secondary to a genetic alteration of kynurenine 3-monooxygenase, a pivotal enzyme in the kynurenine pathway of tryptophan degradation. In rats, prenatal exposure to kynurenine, the direct bioprecursor of kynurenic acid, induces cognitive impairments reminiscent of schizophrenia in adulthood, suggesting a developmental dimension to the link between kynurenic acid and schizophrenia. AIM The purpose of this study was to explore the possible impact of the maternal genotype on kynurenine pathway metabolism. METHODS We exposed pregnant wild-type ( Kmo+/+ ) and heterozygous ( Kmo+/-) mice to kynurenine (10 mg/day) during the last week of gestation and determined the levels of kynurenic acid and two other neuroactive kynurenine pathway metabolites, 3-hydroxykynurenine and quinolinic acid, in fetal brain and placenta on embryonic day 17/18. RESULTS Maternal kynurenine treatment raised kynurenic acid levels significantly more in the brain of heterozygous offspring of Kmo+/- than in the brain of Kmo+/+ offspring. Conversely, 3-hydroxykynurenine and quinolinic acid levels in the fetal brain tended to be lower in heterozygous animals derived from kynurenine-treated Kmo+/- mice than in corresponding Kmo+/+ offspring. Genotype-related effects on the placenta were qualitatively similar but less pronounced. Kynurenine treatment also caused a preferential elevation in cerebral kynurenic acid levels in Kmo+/- compared to Kmo+/+ dams. CONCLUSIONS The disproportionate kynurenic acid increase in the brain of Kmo+/- animals indicates that the maternal Kmo genotype may play a key role in the pathophysiology of schizophrenia.
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Affiliation(s)
- Sarah Beggiato
- 1 Department of Life Sciences and Biotechnologies, University of Ferrara, Ferrara, Italy.,2 Laboratory for the Technology of Advanced Therapies (LTTA Centre), University of Ferrara, Ferrara, Italy
| | - Francesca M Notarangelo
- 3 Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, USA
| | | | - Flaviano Giorgini
- 4 Department of Genetics and Genome Biology, University of Leicester, Leicester, UK
| | - Robert Schwarcz
- 3 Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, USA
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Chiappelli J, Notarangelo FM, Pocivavsek A, Thomas MAR, Rowland LM, Schwarcz R, Hong LE. Influence of plasma cytokines on kynurenine and kynurenic acid in schizophrenia. Neuropsychopharmacology 2018; 43. [PMID: 29520060 PMCID: PMC6006321 DOI: 10.1038/s41386-018-0038-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Abnormalities in the kynurenine pathway (KP) of tryptophan degradation, leading to the dysfunction of neuroactive KP metabolites in the brain, have been implicated in the pathophysiology of schizophrenia (SZ). One plausible mechanism involves dysregulation of various pro-inflammatory cytokines associated with the disease, which affect indoleamine-2,3-dioxygenase (IDO), a key enzyme for tryptophan to kynurenine conversion. In order to test this hypothesis directly, we measured plasma levels of the major KP metabolites kynurenine and kynurenic acid (KYNA), as well as four major cytokines, in a sample of 106 SZ patients and 104 control participants. In contrast to the replicable findings of elevation of KYNA in the central nervous system in SZ, plasma levels of KYNA were significantly lower in SZ compared to controls (p = .004). Kynurenine levels were significantly correlated with levels of interferon-γ (p < .001), which is involved in the regulation of IDO, in both patients and controls. However, although patients had higher levels of interleukin-6 (IL-6) compared to controls (p = .012), IL-6 levels were not correlated with kynurenine or KYNA, and did not explain group differences in KYNA. Based on the lack of evidence that pro-inflammatory cytokines were significantly related to the KP abnormality in SZ despite an adequate sample size, further studies must consider alternative hypotheses to identify the origins of the KP abnormalities in SZ.
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Affiliation(s)
- Joshua Chiappelli
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, USA.
| | - Francesca M. Notarangelo
- 0000 0001 2175 4264grid.411024.2Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD USA
| | - Ana Pocivavsek
- 0000 0001 2175 4264grid.411024.2Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD USA
| | - Marian A. R. Thomas
- 0000 0001 2175 4264grid.411024.2Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD USA
| | - Laura M. Rowland
- 0000 0001 2175 4264grid.411024.2Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD USA
| | - Robert Schwarcz
- 0000 0001 2175 4264grid.411024.2Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD USA
| | - L. Elliot Hong
- 0000 0001 2175 4264grid.411024.2Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD USA
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