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Shen H, Xu X, Bai Y, Wang X, Wu Y, Zhong J, Wu Q, Luo Y, Shang T, Shen R, Xi M, Sun H. Therapeutic potential of targeting kynurenine pathway in neurodegenerative diseases. Eur J Med Chem 2023; 251:115258. [PMID: 36917881 DOI: 10.1016/j.ejmech.2023.115258] [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: 01/25/2023] [Revised: 02/17/2023] [Accepted: 03/07/2023] [Indexed: 03/11/2023]
Abstract
Kynurenine pathway (KP), the primary pathway of L-tryptophan (Trp) metabolism in mammals, contains several neuroactive metabolites such as kynurenic acid (KA) and quinolinic acid (QA). Its imbalance involved in aging and neurodegenerative diseases (NDs) has attracted much interest in therapeutically targeting KP enzymes and KP metabolite-associated receptors, especially kynurenine monooxygenase (KMO). Currently, many agents have been discovered with significant improvement in animal models but only one aryl hydrocarbon receptor (AHR) agonist 30 (laquinimod) has entered clinical trials for treating Huntington's disease (HD). In this review, we describe neuroactive KP metabolites, discuss the dysregulation of KP in aging and NDs and summarize the development of KP regulators in preclinical and clinical studies, offering an outlook of targeting KP for NDs treatment in future.
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Affiliation(s)
- Hualiang Shen
- Zhejiang Engineering Research Center of Fat-soluble Vitamin, Shaoxing University, Shaoxing, 312000, China; College of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing, 312000, China
| | - Xinde Xu
- Zhejiang Medicine Co. Ltd., Shaoxing, 312500, China
| | - Yalong Bai
- Zhejiang Medicine Co. Ltd., Shaoxing, 312500, China
| | | | - Yibin Wu
- College of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing, 312000, China
| | - Jia Zhong
- College of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing, 312000, China
| | - Qiyi Wu
- College of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing, 312000, China
| | - Yanjuan Luo
- Zhejiang Engineering Research Center of Fat-soluble Vitamin, Shaoxing University, Shaoxing, 312000, China; College of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing, 312000, China
| | - Tianbo Shang
- Zhejiang Engineering Research Center of Fat-soluble Vitamin, Shaoxing University, Shaoxing, 312000, China; College of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing, 312000, China
| | - Runpu Shen
- Zhejiang Engineering Research Center of Fat-soluble Vitamin, Shaoxing University, Shaoxing, 312000, China; College of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing, 312000, China
| | - Meiyang Xi
- Zhejiang Engineering Research Center of Fat-soluble Vitamin, Shaoxing University, Shaoxing, 312000, China; College of Chemistry and Chemical Engineering, Shaoxing University, Shaoxing, 312000, China.
| | - Haopeng Sun
- Department of Medicinal Chemistry, China Pharmaceutical University, Nanjing, 210009, China.
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2
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Livingstone K, Siebold K, Meyer S, Martín-Heras V, Daniliuc CG, Gilmour R. Skeletal Ring Contractions via I(I)/I(III) Catalysis: Stereoselective Synthesis of cis-α,α-Difluorocyclopropanes. ACS Catal 2022; 12:14507-14516. [PMID: 36504915 PMCID: PMC9724094 DOI: 10.1021/acscatal.2c04511] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 10/17/2022] [Indexed: 11/12/2022]
Abstract
The clinical success of α,α-difluorocyclopropanes, combined with limitations in the existing synthesis portfolio, inspired the development of an operationally simple, organocatalysis-based strategy to access cis-configured derivatives with high levels of stereoselectivity (up to >20:1 cis:trans). Leveraging an I(I)/I(III)-catalysis platform in the presence of an inexpensive HF source, it has been possible to exploit disubstituted bicyclobutanes (BCBs) as masked cyclobutene equivalents for this purpose. In situ generation of this strained alkene, enabled by Brønsted acid activation, facilitates an unprecedented 4 → 3 fluorinative ring contraction, to furnish cis-α,α-difluorinated cyclopropanes in a highly stereoselective manner (up to 88% yield). Mechanistic studies are disclosed together with conformational analysis (X-ray crystallography and NMR) to validate cis-α,α-difluorocyclopropanes as isosteres of the 1,4-dicarbonyl moiety. Given the importance of this unit in biology and the foundational no → π* interactions that manifest themselves in this conformation (e.g., collagen), it is envisaged that the title motif will find application in focused molecular design.
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3
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The Kynurenine Pathway and Kynurenine 3-Monooxygenase Inhibitors. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27010273. [PMID: 35011505 PMCID: PMC8747024 DOI: 10.3390/molecules27010273] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2021] [Revised: 12/21/2021] [Accepted: 12/22/2021] [Indexed: 12/20/2022]
Abstract
Under normal physiological conditions, the kynurenine pathway (KP) plays a critical role in generating cellular energy and catabolizing tryptophan. Under inflammatory conditions, however, there is an upregulation of the KP enzymes, particularly kynurenine 3-monooxygenase (KMO). KMO has garnered much attention due to its production of toxic metabolites that have been implicated in many diseases and disorders. With many of these illnesses having an inadequate or modest treatment, there exists a need to develop KMO inhibitors that reduce the production of these toxic metabolites. Though prior efforts to find an appropriate KMO inhibitor were unpromising, the development of a KMO crystal structure has provided the opportunity for a rational structure-based design in the development of inhibitors. Therefore, the purpose of this review is to describe the kynurenine pathway, the kynurenine 3-monooxygenase enzyme, and KMO inhibitors and their potential candidacy for clinical use.
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4
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Role of Kynurenine Pathway in Oxidative Stress during Neurodegenerative Disorders. Cells 2021; 10:cells10071603. [PMID: 34206739 PMCID: PMC8306609 DOI: 10.3390/cells10071603] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 06/18/2021] [Accepted: 06/24/2021] [Indexed: 12/12/2022] Open
Abstract
Neurodegenerative disorders are chronic and life-threatening conditions negatively affecting the quality of patients’ lives. They often have a genetic background, but oxidative stress and mitochondrial damage seem to be at least partly responsible for their development. Recent reports indicate that the activation of the kynurenine pathway (KP), caused by an activation of proinflammatory factors accompanying neurodegenerative processes, leads to the accumulation of its neuroactive and pro-oxidative metabolites. This leads to an increase in the oxidative stress level, which increases mitochondrial damage, and disrupts the cellular energy metabolism. This significantly reduces viability and impairs the proper functioning of central nervous system cells and may aggravate symptoms of many psychiatric and neurodegenerative disorders. This suggests that the modulation of KP activity could be effective in alleviating these symptoms. Numerous reports indicate that tryptophan supplementation, inhibition of KP enzymes, and administration or analogs of KP metabolites show promising results in the management of neurodegenerative disorders in animal models. This review gathers and systematizes the knowledge concerning the role of metabolites and enzymes of the KP in the development of oxidative damage within brain cells during neurodegenerative disorders and potential strategies that could reduce the severity of this process.
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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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Liu CY, Huang TT, Chen JL, Chu PY, Lee CH, Lee HC, Lee YH, Chang YY, Yang SH, Jiang JK, Chen WS, Chao Y, Teng HW. Significance of Kynurenine 3-Monooxygenase Expression in Colorectal Cancer. Front Oncol 2021; 11:620361. [PMID: 33937026 PMCID: PMC8085544 DOI: 10.3389/fonc.2021.620361] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 02/18/2021] [Indexed: 12/22/2022] Open
Abstract
Colorectal cancer (CRC) is a leading cause of cancer-related deaths. Because of the lack of reliable prognostic and predictive biomarkers for CRC, most patients are often diagnosed at a late stage. The tryptophan–kynurenine pathway plays a crucial role in promoting cancer progression. Kynurenine is considered an oncometabolite in colon cancer, and its downstream metabolites are also associated with CRC. Kynurenine 3-monooxygenase (KMO), a pivotal enzyme that catalyzes kynurenine metabolism, is essential for several cellular processes. In the current study, we explored the role of KMO in CRC. Immunohistochemical results showed that KMO was upregulated in CRC tissues relative to paired healthy tissue and polyps. Moreover, CRC patients with higher KMO expression were associated with higher metastasis and poorer survival rates. Knockdown of KMO decreased the expression of cancer stem cell markers, as well as the sphere-forming, migration, and invasion abilities of CRC cells. Additionally, blockade of the enzymatic activity of KMO using an inhibitor suppressed sphere formation and cell motility in CRC cells. These findings suggest the clinical relevance of KMO in CRC tumorigenesis and aggressiveness.
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Affiliation(s)
- Chun-Yu Liu
- School of Medicine, National Yang-Ming University, Taipei, Taiwan.,Division of Transfusion Medicine, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan.,Division of Medical Oncology, Department of Oncology, Center for Immuno-Oncology, Taipei Veterans General Hospital, Taipei, Taiwan.,School of Medicine, National Yang Ming Chiao Tung University, Hsinchu, Taiwan
| | - Tzu-Ting Huang
- Division of Medical Oncology, Department of Oncology, Center for Immuno-Oncology, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Ji-Lin Chen
- Division of Medical Oncology, Department of Oncology, Center for Immuno-Oncology, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Pei-Yi Chu
- Department of Pathology, Show Chwan Memorial Hospital, Changhua City, Taiwan.,School of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan
| | - Chia-Han Lee
- Division of Medical Oncology, Department of Oncology, Center for Immuno-Oncology, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Hsin-Chen Lee
- School of Medicine, Institute of Pharmacology, National Yang-Ming Chiao Tung University, New Taipei City, Taiwan
| | - Yu-Hsuan Lee
- Division of Medical Oncology, Department of Oncology, Center for Immuno-Oncology, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Yuan-Ya Chang
- Division of Medical Oncology, Department of Oncology, Center for Immuno-Oncology, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Shung-Haur Yang
- School of Medicine, National Yang-Ming University, Taipei, Taiwan.,School of Medicine, National Yang Ming Chiao Tung University, Hsinchu, Taiwan.,Division of Colon and Rectum Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan.,Department of Surgery, National Yang Ming Chiao Tung University Hospital, Yilan, Taiwan
| | - Jeng-Kai Jiang
- School of Medicine, National Yang-Ming University, Taipei, Taiwan.,School of Medicine, National Yang Ming Chiao Tung University, Hsinchu, Taiwan.,Division of Colon and Rectum Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Wei-Shone Chen
- School of Medicine, National Yang-Ming University, Taipei, Taiwan.,School of Medicine, National Yang Ming Chiao Tung University, Hsinchu, Taiwan.,Division of Colon and Rectum Surgery, Department of Surgery, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Yee Chao
- School of Medicine, National Yang-Ming University, Taipei, Taiwan.,Division of Medical Oncology, Department of Oncology, Center for Immuno-Oncology, Taipei Veterans General Hospital, Taipei, Taiwan.,School of Medicine, National Yang Ming Chiao Tung University, Hsinchu, Taiwan
| | - Hao-Wei Teng
- School of Medicine, National Yang-Ming University, Taipei, Taiwan.,Division of Medical Oncology, Department of Oncology, Center for Immuno-Oncology, Taipei Veterans General Hospital, Taipei, Taiwan.,School of Medicine, National Yang Ming Chiao Tung University, Hsinchu, Taiwan
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7
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Rojewska E, Ciapała K, Piotrowska A, Makuch W, Mika J. Pharmacological Inhibition of Indoleamine 2,3-Dioxygenase-2 and Kynurenine 3-Monooxygenase, Enzymes of the Kynurenine Pathway, Significantly Diminishes Neuropathic Pain in a Rat Model. Front Pharmacol 2018; 9:724. [PMID: 30050435 PMCID: PMC6050382 DOI: 10.3389/fphar.2018.00724] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 06/15/2018] [Indexed: 01/02/2023] Open
Abstract
Neuropathic pain caused by a primary injury or dysfunction in the peripheral or central nervous system is a tremendous therapeutic challenge. Here, we have collected the first evidence from a single study on the potential contributions to neuropathic pain development by enzymes in the kynurenine pathway [tryptophan 2,3-dioxygenase (TDO), indoleamine 2,3-dioxygenase (IDO1/2), kynurenine 3-monooxygenase (KMO); kynureninase, 3-hydroxyanthranilate-3,4-dioxygenase (HAOO)] at the spinal cord and dorsal root ganglia (DRG) levels. At the spinal cord, mRNA levels of IDO2, KMO, and HAOO were elevated as measured on day 7 after chronic constriction injury in a rat model, parallel to the C1q-positive cell activation. According to our data obtained from primary microglial cell cultures, all enzymes of the kynurenine pathway except TDO were derived from these cells; however, the activation of microglia induced stronger changes in IDO2 and KMO. Our pharmacological studies gave evidence that the repeated intraperitoneal administration of minocycline, a microglia/macrophage inhibitor, not only attenuated tactile and thermal hypersensitivity but also diminished the levels of IDO2 and KMO mRNA. Our further pharmacological studies confirmed that IDO2 and KMO enzymes take part in the development of neuropathic pain, since we observed that the repeated administration of IDO2 (1-methyl-D-tryptophan) and KMO [UPF 648 – (1S,2S)-2-(3,4-dichlorobenzoyl)cyclopropanecarboxylic acid] inhibitors diminished hypersensitivity development as measured on days 2 and 7. The results of our studies show that the kynurenine pathway is an important mediator of neuropathic pain pathology in rats and indicate that IDO2 and KMO represent novel pharmacological targets for treating neuropathy.
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Affiliation(s)
- Ewelina Rojewska
- Department of Pain Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Katarzyna Ciapała
- Department of Pain Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Anna Piotrowska
- Department of Pain Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Wioletta Makuch
- Department of Pain Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
| | - Joanna Mika
- Department of Pain Pharmacology, Institute of Pharmacology, Polish Academy of Sciences, Krakow, Poland
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8
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Sathyasaikumar KV, Breda C, Schwarcz R, Giorgini F. Assessing and Modulating Kynurenine Pathway Dynamics in Huntington's Disease: Focus on Kynurenine 3-Monooxygenase. Methods Mol Biol 2018; 1780:397-413. [PMID: 29856028 DOI: 10.1007/978-1-4939-7825-0_18] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The link between disturbances in kynurenine pathway (KP) metabolism and Huntington's disease (HD) pathogenesis has been explored for a number of years. Several novel genetic and pharmacological tools have recently been developed to modulate key regulatory steps in the KP such as the reaction catalyzed by the enzyme kynurenine 3-monooxygenase (KMO). This insight has offered new options for exploring the mechanistic link between this metabolic pathway and HD, and provided novel opportunities for the development of candidate drug-like compounds. Here, we present an overview of the field, focusing on some novel approaches for interrogating the pathway experimentally.
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Affiliation(s)
- Korrapati V Sathyasaikumar
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Carlo Breda
- Department of Genetics and Genome Biology, University of Leicester, Leicester, UK
| | - Robert Schwarcz
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Flaviano Giorgini
- Department of Genetics and Genome Biology, University of Leicester, Leicester, UK.
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Goeden N, Notarangelo FM, Pocivavsek A, Beggiato S, Bonnin A, Schwarcz R. Prenatal Dynamics of Kynurenine Pathway Metabolism in Mice: Focus on Kynurenic Acid. Dev Neurosci 2017; 39:519-528. [PMID: 29080891 DOI: 10.1159/000481168] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Accepted: 08/31/2017] [Indexed: 01/09/2023] Open
Abstract
The kynurenine pathway (KP), the major catabolic route of tryptophan in mammals, contains several neuroactive metabolites, including kynurenic acid (KYNA) and 3-hydroxykynurenine (3-HK). KP metabolism, and especially the fate of KYNA, during pregnancy is poorly understood, yet it may play a significant role in the development of psychiatric disorders later in life. The present study was designed to investigate the prenatal features of KP metabolism in vivo, with special focus on KYNA. To this end, pregnant CD-1 mice were treated systemically with kynurenine (100 mg/kg), KYNA (10 mg/kg), or saline on embryonic day 18. As expected, administration of either kynurenine or KYNA increased KYNA levels in the maternal plasma and placenta. Maternal kynurenine treatment also raised kynurenine levels in the fetal plasma and brain, demonstrating the ability of this pivotal KP metabolite to cross the placenta and increase the levels of both KYNA and 3-HK in the fetal brain. In contrast, maternal administration of KYNA caused only a small, nonsignificant elevation in KYNA levels in fetal plasma and brain. Complementary experiments using an ex vivo placental perfusion procedure confirmed the significant transplacental transfer of kynurenine and demonstrated that only a very small fraction of maternal kynurenine is converted to KYNA in the placenta and released into the fetal compartment under physiological conditions. Jointly, these results help to clarify the contributions of the maternal circulation and the placenta to fetal KYNA in the late prenatal period.
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Affiliation(s)
- Nick Goeden
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
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10
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Jacobs KR, Castellano-Gonzalez G, Guillemin GJ, Lovejoy DB. Major Developments in the Design of Inhibitors along the Kynurenine Pathway. Curr Med Chem 2017; 24:2471-2495. [PMID: 28464785 PMCID: PMC5748880 DOI: 10.2174/0929867324666170502123114] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 03/13/2017] [Accepted: 04/18/2017] [Indexed: 12/20/2022]
Abstract
Disrupted kynurenine pathway (KP) metabolism has been implicated in the progression of neurodegenerative disease, psychiatric disorders and cancer. Modulation of enzyme activity along this pathway may therefore offer potential new therapeutic strategies for these conditions. Considering their prominent positions in the KP, the enzymes indoleamine 2,3-dioxygenase, kynurenine 3-monooxygenase and kynurenine aminotransferase, appear the most attractive targets. Already, increasing interest in this pathway has led to the identification of a number of potent and selective enzyme inhibitors with promising pre-clinical data and the elucidation of several enzyme crystal structures provides scope to rationalize the molecular mechanisms of inhibitor activity. The field seems poised to yield one or more inhibitors that should find clinical utility.
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Affiliation(s)
- Kelly R Jacobs
- Neuroinflammation Group, Department of Biomedical Research, Faculty of Medicine and Health Sciences, Macquarie University, Sydney. Australia
| | - Gloria Castellano-Gonzalez
- Neuroinflammation Group, Department of Biomedical Research, Faculty of Medicine and Health Sciences, Macquarie University, Sydney. Australia
| | - Gilles J Guillemin
- Department of Biomedical Research, Faculty of Medicine and Health Science, Macquarie University, 2 Technology Place, Sydney. Australia
| | - David B Lovejoy
- Department of Biomedical Research, Faculty of Medicine and Health Science, Macquarie University, 2 Technology Place, Sydney. Australia
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11
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Involvement of the kynurenine pathway in the pathogenesis of Parkinson’s disease. Prog Neurobiol 2017; 155:76-95. [DOI: 10.1016/j.pneurobio.2015.12.009] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 12/18/2015] [Accepted: 12/30/2015] [Indexed: 12/14/2022]
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12
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Fazio F, Carrizzo A, Lionetto L, Damato A, Capocci L, Ambrosio M, Battaglia G, Bruno V, Madonna M, Simmaco M, Nicoletti F, Vecchione C. Vasorelaxing Action of the Kynurenine Metabolite, Xanthurenic Acid: The Missing Link in Endotoxin-Induced Hypotension? Front Pharmacol 2017; 8:214. [PMID: 28507519 PMCID: PMC5410560 DOI: 10.3389/fphar.2017.00214] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 04/05/2017] [Indexed: 11/17/2022] Open
Abstract
The kynurenine pathway of tryptophan metabolism is activated by pro-inflammatory cytokines. L-kynurenine, an upstream metabolite of the pathway, acts as a putative endothelium-derived relaxing factor, and has been hypothesized to play a causative role in the pathophysiology of inflammation-induced hypotension. Here, we show that xanthurenic acid (XA), the transamination product of 3-hydroxykynurenine, is more efficacious than L-kynurenine in causing relaxation of a resistance artery, but fails to relax pre-contracted aortic rings. In the mesenteric artery, XA enhanced activating phosphorylation of endothelial nitric oxide synthase (NOS), and the relaxing action of XA was abrogated by pharmacological inhibition of NOS and endothelial-derived hyperpolarizing factor. Systemic injection of XA reduced blood pressure in mice, and serum levels of XA increased by several fold in response to a pulse with the endotoxin, lipopolysaccharide (LPS). LPS-induced hypotension in mice was prevented by pre-treatment with the kynurenine monooxygenase (KMO) inhibitor, Ro-618048, which lowered serum levels of XA but enhanced serum levels of L-kynurenine. UPF 648, another KMO inhibitor, could also abrogate LPS-induced hypotension. Our data identify XA as a novel vasoactive compound and suggest that formation of XA is a key event in the pathophysiology of inflammation-induced hypotension.
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Affiliation(s)
| | | | - Luana Lionetto
- Advanced Molecular Diagnostic, IDI Istituto Dermopatico dell'Immacolata (IRCCS),Rome, Italy
| | - Antonio Damato
- Istituto Neurologico Mediterraneo (IRCCS),Pozzilli, Italy
| | - Luca Capocci
- Istituto Neurologico Mediterraneo (IRCCS),Pozzilli, Italy
| | | | | | - Valeria Bruno
- Istituto Neurologico Mediterraneo (IRCCS),Pozzilli, Italy.,Department of Physiology and Pharmacology, Sapienza University of RomeRome, Italy
| | | | - Maurizio Simmaco
- School of Medicine and Psychology, NESMOS Department, Sant'Andrea Hospital, Sapienza University of RomeRome, Italy
| | - Ferdinando Nicoletti
- Istituto Neurologico Mediterraneo (IRCCS),Pozzilli, Italy.,Department of Physiology and Pharmacology, Sapienza University of RomeRome, Italy
| | - Carmine Vecchione
- Istituto Neurologico Mediterraneo (IRCCS),Pozzilli, Italy.,Department of Medicine and Surgery, University of SalernoBaronissi, Italy
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Notarangelo FM, Schwarcz R. Restraint Stress during Pregnancy Rapidly Raises Kynurenic Acid Levels in Mouse Placenta and Fetal Brain. Dev Neurosci 2017; 38:458-468. [PMID: 28214871 DOI: 10.1159/000455228] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 12/19/2016] [Indexed: 12/13/2022] Open
Abstract
Stressful events during pregnancy adversely affect brain development and may increase the risk of psychiatric disorders later in life. Early changes in the kynurenine (KYN) pathway (KP) of tryptophan (TRP) degradation, which contains several neuroactive metabolites, including kynurenic acid (KYNA), 3-hydroxykynurenine (3-HK), and quinolinic acid (QUIN), may constitute a molecular link between prenatal stress and delayed pathological consequences. To begin testing this hypothesis experimentally, we examined the effects of a 2-h restraint stress on KP metabolism in pregnant FVB/N mice on gestational day 17. TRP, KYN, KYNA, 3-HK, and QUIN levels were measured in maternal and fetal plasma and brain, as well as in the placenta, immediately after stress termination and 2 h later. In the same animals, we determined the activity of TRP 2,3-dioxygenase (TDO) in the maternal liver and in the placenta. Compared to unstressed controls, mostly transient changes in KP metabolism were observed in all of the tissues examined. Specifically, stress caused significant elevations of KYNA levels in the maternal plasma, placenta, and fetal brain, and also resulted in increased levels of TRP and KYN in the placenta, fetal plasma, and fetal brain. In contrast, 3-HK and QUIN levels remained unchanged from control values in all tissues at any time point. In the maternal liver, TDO activity was increased 2 h after stress cessation. Taken together, these findings indicate that an acute stress during the late gestational period preferentially affects the KYNA branch of KP metabolism in the fetal brain. Possible long-term consequences for postnatal brain development and pathology remain to be examined.
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Affiliation(s)
- Francesca M Notarangelo
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
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Barkhuizen M, van den Hove DLA, Vles JSH, Steinbusch HWM, Kramer BW, Gavilanes AWD. 25 years of research on global asphyxia in the immature rat brain. Neurosci Biobehav Rev 2017; 75:166-182. [PMID: 28161509 DOI: 10.1016/j.neubiorev.2017.01.042] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 01/27/2017] [Accepted: 01/29/2017] [Indexed: 10/20/2022]
Abstract
Hypoxic-ischemic encephalopathy remains a common cause of brain damage in neonates. Preterm infants have additional complications, as prematurity by itself increases the risk of encephalopathy. Currently, therapy for this subset of asphyxiated infants is limited to supportive care. There is an urgent need for therapies in preterm infants - and for representative animal models for preclinical drug development. In 1991, a novel rodent model of global asphyxia in the preterm infant was developed in Sweden. This method was based on the induction of asphyxia during the birth processes itself by submerging pups, still in the uterine horns, in a water bath followed by C-section. This insult occurs at a time-point when the rodent brain maturity resembles the brain of a 22-32 week old human fetus. This model has developed over the past 25 years as an established model of perinatal global asphyxia in the early preterm brain. Here we summarize the knowledge gained on the short- and long-term neuropathological and behavioral effects of asphyxia on the immature central nervous system.
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Affiliation(s)
- M Barkhuizen
- Department of Pediatrics, Maastricht University Medical Center (MUMC), Maastricht, The Netherlands; Department of Translational Neuroscience, School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands; DST/NWU Preclinical Drug Development Platform, North-West University, Potchefstroom, South Africa
| | - D L A van den Hove
- Department of Translational Neuroscience, School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands; Department of Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, Würzburg, Germany
| | - J S H Vles
- Department of Translational Neuroscience, School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands; Child Neurology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - H W M Steinbusch
- Department of Translational Neuroscience, School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands
| | - B W Kramer
- Department of Pediatrics, Maastricht University Medical Center (MUMC), Maastricht, The Netherlands; Department of Translational Neuroscience, School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands
| | - A W D Gavilanes
- Department of Pediatrics, Maastricht University Medical Center (MUMC), Maastricht, The Netherlands; Department of Translational Neuroscience, School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands; Institute of Biomedicine, Facultad de Ciencias Médicas, Universidad Católica de Santiago de Guayaquil, Ecuador.
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15
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Abstract
OBJECTIVE There is a growing interest in the role of kynurenine pathway and tryptophan metabolites in the pathophysiology of depression. In the present study, the metabolism of tryptophan along the kynurenine pathway was analysed in a rat model of depression. METHODS Kynurenic acid (KYNA) and 3-hydroxykynurenine (3-HK) were measured by high-performance liquid chromatography (HPLC) in prefrontal cortex (PFC) and frontal cortex (FC) in a rat model of depression, the Flinders Sensitive Line (FSL) and their controls, the Flinders Resistant Line (FRL) rats. In addition, KYNA was also measured in hippocampus, striatum and cerebellum. RESULTS KYNA levels were reduced in the PFC of FSL rats compared with FRL rats, but did not differ with regard to the FC, hippocampus, striatum or cerebellum. 3-HK levels in PFC and FC, representing the activity of the microglial branch of the kynurenine pathway, did not differ between the FSL and FRL strains. CONCLUSION Our results suggest an imbalanced metabolism of the kynurenine pathway in the PFC of FSL rats.
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Forrest CM, McNair K, Pisar M, Khalil OS, Darlington LG, Stone TW. Altered hippocampal plasticity by prenatal kynurenine administration, kynurenine-3-monoxygenase (KMO) deletion or galantamine. Neuroscience 2015; 310:91-105. [PMID: 26365611 PMCID: PMC4642643 DOI: 10.1016/j.neuroscience.2015.09.022] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 08/11/2015] [Accepted: 09/07/2015] [Indexed: 11/16/2022]
Abstract
Glutamate receptors sensitive to N-methyl-D-aspartate (NMDA) are involved in embryonic brain development but their activity may be modulated by the kynurenine pathway of tryptophan metabolism which includes an agonist (quinolinic acid) and an antagonist (kynurenic acid) at these receptors. Our previous work has shown that prenatal inhibition of the pathway produces abnormalities of brain development. In the present study kynurenine and probenecid (both 100mg/kg, doses known to increase kynurenic acid levels in the brain) were administered to female Wistar rats on embryonic days E14, E16 and E18 of gestation and the litter was allowed to develop to post-natal day P60. Western blotting revealed no changes in hippocampal expression of several proteins previously found to be altered by inhibition of the kynurenine pathway including the NMDA receptor subunits GluN1, GluN2A and GluN2B, as well as doublecortin, Proliferating Cell Nuclear Antigen (PCNA), sonic hedgehog and unco-ordinated (unc)-5H1 and 5H3. Mice lacking the enzyme kynurenine-3-monoxygenase (KMO) also showed no changes in hippocampal expression of several of these proteins or the 70-kDa and 100-kDa variants of Disrupted in Schizophrenia-1 (DISC1). Electrical excitability of pyramidal neurons in the CA1 region of hippocampal slices was unchanged, as was paired-pulse facilitation and inhibition. Long-term potentiation was decreased in the kynurenine-treated rats and in the KMO(-/-) mice, but galantamine reversed this effect in the presence of nicotinic receptor antagonists, consistent with evidence that it can potentiate glutamate at NMDA receptors. It is concluded that interference with the kynurenine pathway in utero can have lasting effects on brain function of the offspring, implying that the kynurenine pathway is involved in the regulation of early brain development.
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Affiliation(s)
- C M Forrest
- Institute of Neuroscience and Psychology, West Medical Building, University of Glasgow, Glasgow G12 8QQ, UK
| | - K McNair
- Institute of Neuroscience and Psychology, West Medical Building, University of Glasgow, Glasgow G12 8QQ, UK
| | - M Pisar
- Institute of Neuroscience and Psychology, West Medical Building, University of Glasgow, Glasgow G12 8QQ, UK
| | - O S Khalil
- Institute of Neuroscience and Psychology, West Medical Building, University of Glasgow, Glasgow G12 8QQ, UK
| | - L G Darlington
- Ashtead Hospital, The Warren, Ashtead, Surrey KT21 2SB, UK
| | - T W Stone
- Institute of Neuroscience and Psychology, West Medical Building, University of Glasgow, Glasgow G12 8QQ, UK.
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Reyes Ocampo J, Lugo Huitrón R, González-Esquivel D, Ugalde-Muñiz P, Jiménez-Anguiano A, Pineda B, Pedraza-Chaverri J, Ríos C, Pérez de la Cruz V. Kynurenines with neuroactive and redox properties: relevance to aging and brain diseases. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2014; 2014:646909. [PMID: 24693337 PMCID: PMC3945746 DOI: 10.1155/2014/646909] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/10/2013] [Revised: 12/12/2013] [Accepted: 12/15/2013] [Indexed: 11/18/2022]
Abstract
The kynurenine pathway (KP) is the main route of tryptophan degradation whose final product is NAD(+). The metabolism of tryptophan can be altered in ageing and with neurodegenerative process, leading to decreased biosynthesis of nicotinamide. This fact is very relevant considering that tryptophan is the major source of body stores of the nicotinamide-containing NAD(+) coenzymes, which is involved in almost all the bioenergetic and biosynthetic metabolism. Recently, it has been proposed that endogenous tryptophan and its metabolites can interact and/or produce reactive oxygen species in tissues and cells. This subject is of great importance due to the fact that oxidative stress, alterations in KP metabolites, energetic deficit, cell death, and inflammatory events may converge each other to enter into a feedback cycle where each one depends on the other to exert synergistic actions among them. It is worth mentioning that all these factors have been described in aging and in neurodegenerative processes; however, has so far no one established any direct link between alterations in KP and these factors. In this review, we describe each kynurenine remarking their redox properties, their effects in experimental models, their alterations in the aging process.
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Affiliation(s)
- Jazmin Reyes Ocampo
- Departamento de Neuroquímica, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, S.S.A., Insurgentes Sur 3877, 14269 México, DF, Mexico
- Área de Neurociencias, Departamento de Biología de la Reproducción, Universidad Autónoma Metropolitana-Iztapalapa, 09340 México, DF, Mexico
| | - Rafael Lugo Huitrón
- Departamento de Neuroquímica, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, S.S.A., Insurgentes Sur 3877, 14269 México, DF, Mexico
| | - Dinora González-Esquivel
- Departamento de Neuroquímica, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, S.S.A., Insurgentes Sur 3877, 14269 México, DF, Mexico
| | - Perla Ugalde-Muñiz
- Departamento de Neuroquímica, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, S.S.A., Insurgentes Sur 3877, 14269 México, DF, Mexico
| | - Anabel Jiménez-Anguiano
- Área de Neurociencias, Departamento de Biología de la Reproducción, Universidad Autónoma Metropolitana-Iztapalapa, 09340 México, DF, Mexico
| | - Benjamín Pineda
- Laboratorio de Neuroinmunología, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, S.S.A., 14269 México, DF, Mexico
| | - José Pedraza-Chaverri
- Departamento de Biología, Facultad de Química, Universidad Nacional Autónoma de México, 04510 México, DF, Mexico
| | - Camilo Ríos
- Departamento de Neuroquímica, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, S.S.A., Insurgentes Sur 3877, 14269 México, DF, Mexico
| | - Verónica Pérez de la Cruz
- Departamento de Neuroquímica, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, S.S.A., Insurgentes Sur 3877, 14269 México, DF, Mexico
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Amaral M, Outeiro TF, Scrutton NS, Giorgini F. The causative role and therapeutic potential of the kynurenine pathway in neurodegenerative disease. J Mol Med (Berl) 2013; 91:705-13. [PMID: 23636512 DOI: 10.1007/s00109-013-1046-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Revised: 04/11/2013] [Accepted: 04/17/2013] [Indexed: 12/16/2022]
Abstract
Metabolites of the kynurenine pathway (KP), which arise from the degradation of tryptophan, have been studied in detail for over a century and garnered the interest of the neuroscience community in the late 1970s and early 1980s with work uncovering the neuromodulatory potential of this pathway. Much research in the following decades has found that perturbations in the levels of KP metabolites likely contribute to the pathogenesis of several neurodegenerative diseases. More recently, it has become apparent that targeting KP enzymes, in particular kynurenine 3-monooxygenase (KMO), may hold substantial therapeutic potential for these disorders. Here we provide an overview of the KP, the neuroactive properties of KP metabolites and their role in neurodegeneration. We also discuss KMO as a therapeutic target for these disorders, and our recent resolution of the crystallographic structure of KMO, which will permit the development of new and improved KMO inhibitors which may ultimately expedite clinical application of these compounds.
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Affiliation(s)
- Marta Amaral
- Department of Genetics, University of Leicester, Leicester, LE1 7RH, UK
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19
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Structural basis of kynurenine 3-monooxygenase inhibition. Nature 2013; 496:382-5. [PMID: 23575632 PMCID: PMC3736096 DOI: 10.1038/nature12039] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Accepted: 02/22/2013] [Indexed: 12/02/2022]
Abstract
Inhibition of kynurenine 3-monooxygenase (KMO), an enzyme in the eukaryotic tryptophan catabolic pathway (i.e. kynurenine pathway), leads to amelioration of Huntington’s disease-relevant phenotypes in yeast, fruit fly, and mouse models1–5, as well as a mouse model of Alzheimer’s disease3. KMO is a FAD-dependent monooxygenase, and is located in the outer mitochondrial membrane where it converts L-kynurenine to 3-hydroxykynurenine. Perturbations in the levels of kynurenine pathway metabolites have been linked to the pathogenesis of a spectrum of brain disorders6, as well as cancer7,8, and several peripheral inflammatory conditions9. Despite the importance of KMO as a target for neurodegenerative disease, the molecular basis of KMO inhibition by available lead compounds has remained hitherto unknown. Here we report the first crystal structure of KMO, in the free form and in complex with the tight-binding inhibitor UPF 648. UPF 648 binds close to the FAD cofactor and perturbs the local active site structure, preventing productive binding of the substrate kynurenine. Functional assays and targeted mutagenesis revealed that the active site architecture and UPF 648 binding are essentially identical in human KMO, validating the yeast KMO:UPF 648 structure as a template for structure-based drug design. This will inform the search for new KMO inhibitors that are able to cross the blood-brain barrier in targeted therapies against neurodegenerative diseases such as Huntington’s, Alzheimer’s, and Parkinson’s diseases.
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20
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Schwarcz R, Bruno JP, Muchowski PJ, Wu HQ. Kynurenines in the mammalian brain: when physiology meets pathology. Nat Rev Neurosci 2012; 13:465-77. [PMID: 22678511 DOI: 10.1038/nrn3257] [Citation(s) in RCA: 1030] [Impact Index Per Article: 85.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The essential amino acid tryptophan is not only a precursor of serotonin but is also degraded to several other neuroactive compounds, including kynurenic acid, 3-hydroxykynurenine and quinolinic acid. The synthesis of these metabolites is regulated by an enzymatic cascade, known as the kynurenine pathway, that is tightly controlled by the immune system. Dysregulation of this pathway, resulting in hyper-or hypofunction of active metabolites, is associated with neurodegenerative and other neurological disorders, as well as with psychiatric diseases such as depression and schizophrenia. With recently developed pharmacological agents, it is now possible to restore metabolic equilibrium and envisage novel therapeutic interventions.
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Affiliation(s)
- Robert Schwarcz
- University of Maryland School of Medicine, Baltimore, Maryland 21228, USA. rschwarc@mprc. umaryland.edu
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21
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Feng Y, Bowden BF, Kapoor V. Ianthellamide A, a selective kynurenine-3-hydroxylase inhibitor from the Australian marine sponge Ianthella quadrangulata. Bioorg Med Chem Lett 2012; 22:3398-401. [PMID: 22525315 DOI: 10.1016/j.bmcl.2012.04.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Revised: 03/29/2012] [Accepted: 04/02/2012] [Indexed: 12/27/2022]
Abstract
Ianthellamide A (1), a novel octopamine derivative, was isolated from the Australian marine sponge Ianthella quadrangulata. Compound 1 selectively inhibited the activity of kynurenine 3-hydroxylase with an IC(50) value of 1.5 μM. It also significantly increased the level of endogenous kynurenic acid in rat brain and hence has the potential as a neuroprotective agent in the treatment of neurodegenerative disorders.
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Affiliation(s)
- Yunjiang Feng
- Eskitis Institute, Griffith University, Brisbane, QLD 4111, Australia.
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22
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An exploration of the associations of pregnancy and perinatal features with cytokines and tryptophan/kynurenine metabolism in children with attention-deficit hyperactivity disorder (ADHD). ACTA ACUST UNITED AC 2011; 3:301-18. [PMID: 21785943 DOI: 10.1007/s12402-011-0062-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Accepted: 07/08/2011] [Indexed: 10/18/2022]
Abstract
Intra-individual variability of the characteristics of children with attention-deficit hyperactivity (ADHD) may reflect compromised glial energy supply in the synapse. We reported recently that while serum levels of a glial marker, the cytokine S100B, were not seriously altered, levels of other cytokines and tryptophan metabolites were related to symptoms, attention and variability. Here, we explore with a regression analysis whether levels of these substances were associated with features of the index pregnancy of potential aetiological significance. Serum was taken from 35 children with DSM-IV ADHD (14 on medication) and 21 typically developing controls to measure 8 cytokines (S100B, IL-2, IL-6, IL-10, IL-13, IL-16, TNF-α and IFN-γ) and 5 metabolites (Tryptophan, Kynurenine, Kynurenate [KA], 3-hydroxy-kynurenine [3HK] and 5-hydroxyindole acetic acid [5-HIAA]). The mothers received a 124-item questionnaire on features surrounding the pregnancy. (1) For children with ADHD, a shorter pregnancy and smaller birth weight were associated statistically with increased 3HK and IFN-γ and for obstetric problems with decreased TNF-α levels. (2) Maternal smoking related to decreasing kynurenine and increasing 3HK and S100B levels in ADHD children. Paternal smoking was associated with increased tryptophan in the controls and increased IL-6 levels in ADHD children. (3) The taking of supplements often related to decreasing TNF-α, increasing IL-10 and lower 5-HIAA levels in the ADHD children. Less 5-HIAA but more tryptophan was associated with earlier and later life events, respectively. (4) Increased IL-16 and 5-HIAA levels in the ADHD group related to reports of poorer infant health. Unexpectedly, more child care (seafood and time together) in ADHD than healthy families was implicated by lower tryptophan levels and an altered balance of pro-inflammatory cytokines. Across measures control families generally showed either non-significant associations or the opposite to those of the ADHD group. In ADHD children more than controls, the balance of potentially toxic or protective kynurenine metabolites and of pro- over anti-inflammatory cytokines may reflect the perinatal experience associated with stress, but not with maternal illness.
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Peripheral and cerebral metabolic abnormalities of the tryptophan-kynurenine pathway in a murine model of major depression. Behav Brain Res 2010; 210:84-91. [PMID: 20153778 DOI: 10.1016/j.bbr.2010.02.014] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 02/02/2010] [Accepted: 02/05/2010] [Indexed: 11/26/2022]
Abstract
Occurring both peripherally and centrally, the kynurenine pathway (KP) - an alternative pathway to 5-HT synthesis from tryptophan (TRP) - could be of particular value to better understand the link between peripheral changes of circulating levels of glucocorticoids (GC)/proinflammatory cytokines and altered neurotransmission observed in depressed patients. Indeed, it is activated by these mediators of stress and can produce several neuroactive compounds like quinolinic acid (QUIN) and kynurenic acid (KYNA) that can respectively increase and decrease glutamate concentration in brain. In order to characterize the role of both the peripheral and cerebral KP in the pathophysiology of depressive disorders, we used the Unpredictable Chronic Mild Stress (UCMS) to induce a depressive-like syndrome and we then measured the level of relevant TRP-KYN pathway metabolites: KYN, 3-hydroxykynurenine (3HK; precursor of QUIN) and KYNA. We also measured TRP-5HT pathway metabolites: TRP, 5-HT, 5-HIAA. We showed that UCMS increased TRP catabolism along the KP in the periphery. 5-HT and KYN were found to be strongly negatively correlated in all brain structures of control mice and of UCMS mice except in the hippocampus. More importantly we found that KYN was preferentially metabolized along the QUIN pathway at the subcortical level (amygdala/striatum) whereas, at the cortical level (cingulate cortex), the QUIN pathway was reduced. Considering the role of these metabolites on the glutamatergic neurotransmission, we propose that such KP alterations could participate to the cortical/subcortical glutamatergic alterations reported in depressed patients.
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Amori L, Guidetti P, Pellicciari R, Kajii Y, Schwarcz R. On the relationship between the two branches of the kynurenine pathway in the rat brain in vivo. J Neurochem 2009; 109:316-25. [PMID: 19226371 DOI: 10.1111/j.1471-4159.2009.05893.x] [Citation(s) in RCA: 118] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In the mammalian brain, kynurenine aminotransferase II (KAT II) and kynurenine 3-monooxygenase (KMO), key enzymes of the kynurenine pathway (KP) of tryptophan degradation, form the neuroactive metabolites kynurenic acid (KYNA) and 3-hydroxykynurenine (3-HK), respectively. Although physically segregated, both enzymes use the pivotal KP metabolite l-kynurenine as a substrate. We studied the functional consequences of this cellular compartmentalization in vivo using two specific tools, the KAT II inhibitor BFF 122 and the KMO inhibitor UPF 648. The acute effects of selective KAT II or KMO inhibition were studied using a radiotracing method in which the de novo synthesis of KYNA, and of 3-HK and its downstream metabolite quinolinic acid (QUIN), is monitored following an intrastriatal injection of (3)H-kynurenine. In naïve rats, intrastriatal BFF 122 decreased newly formed KYNA by 66%, without influencing 3-HK or QUIN production. Conversely, UPF 648 reduced 3-HK synthesis (by 64%) without affecting KYNA formation. Similar, selective effects of KAT II and KMO inhibition were observed when the inhibitors were applied acutely together with the excitotoxin QUIN, which impairs local KP metabolism. Somewhat different effects of KMO (but not KAT II) inhibition were obtained in rats that had received an intrastriatal QUIN injection 7 days earlier. In these neuron-depleted striata, UPF 648 not only decreased both 3-HK and QUIN production (by 77% and 66%, respectively) but also moderately raised KYNA synthesis (by 27%). These results indicate a remarkable functional segregation of the two pathway branches in the brain, boding well for the development of selective KAT II or KMO inhibitors for cognitive enhancement and neuroprotection, respectively.
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Affiliation(s)
- Laura Amori
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, Maryland, USA
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25
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Induction of the kynurenine pathway by neurotropic influenza a virus infection. J Neurosci Res 2008; 86:3674-83. [DOI: 10.1002/jnr.21799] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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26
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Abstract
L-kynurenine is an intermediate in the pathway of the metabolism of L-tryptophan to nicotinic acid. L-kynurenine is formed in the mammalian brain (40%) and is taken up from the periphery (60%), indicating that it can be transported across the BBB. It was discovered some 30 years ago that compounds in the kynurenine family have neuroactive properties. L-kynurenine, the central agent of this pathway, can be converted into two other important compounds: the neuroprotective kynurenic acid and the neurotoxic quinolinic acid. Kynurenines have been shown to be involved in many diverse physiological and pathological processes. There are a number of neurodegenerative disorders whose pathogenesis has been demonstrated to involve multiple imbalances of the kynurenine pathway metabolism. This review summarizes the main steps of the kynurenine pathway under normal conditions, discusses the metabolic disturbances and changes in this pathway in certain neurodegenerative disorders, and finally introduces the therapeutic possibilities with kynurenines.
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Affiliation(s)
- Hermina Robotka
- University of Szeged, Department of Physiology, Anatomy & Neuroscience, POB 533, and,Department of Neurology, POB 427, H-6701 Szeged, Hungary
| | - József Toldi
- University of Szeged, Department of Physiology, Anatomy & Neuroscience, POB 533, H-6701 Szeged, Hungary
| | - László Vécsei
- University of Szeged, Department of Neurology, POB 427, H-6701 Szeged, Hungary
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