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Stone TW, Darlington LG, Badawy AAB, Williams RO. The Complex World of Kynurenic Acid: Reflections on Biological Issues and Therapeutic Strategy. Int J Mol Sci 2024; 25:9040. [PMID: 39201726 PMCID: PMC11354734 DOI: 10.3390/ijms25169040] [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: 07/23/2024] [Revised: 08/13/2024] [Accepted: 08/14/2024] [Indexed: 09/03/2024] Open
Abstract
It has been unequivocally established that kynurenic acid has a number of actions in a variety of cells and tissues, raising, in principle, the possibility of targeting its generation, metabolism or sites of action to manipulate those effects to a beneficial therapeutic end. However, many basic aspects of the biology of kynurenic acid remain unclear, potentially leading to some confusion and misinterpretations of data. They include questions of the source, generation, targets, enzyme expression, endogenous concentrations and sites of action. This essay is intended to raise and discuss many of these aspects as a source of reference for more balanced discussion. Those issues are followed by examples of situations in which modulating and correcting kynurenic acid production or activity could bring significant therapeutic benefit, including neurological and psychiatric conditions, inflammatory diseases and cell protection. More information is required to obtain a clear overall view of the pharmacological environment relevant to kynurenic acid, especially with respect to the active concentrations of kynurenine metabolites in vivo and changed levels in disease. The data and ideas presented here should permit a greater confidence in appreciating the sites of action and interaction of kynurenic acid under different local conditions and pathologies, enhancing our understanding of kynurenic acid itself and the many clinical conditions in which manipulating its pharmacology could be of clinical value.
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Affiliation(s)
- Trevor W. Stone
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford OX3 7FY, UK;
| | - L. Gail Darlington
- Worthing Hospital, University Hospitals Sussex NHS Foundation Trust, Worthing BN11 2DH, UK
| | - Abdulla A.-B. Badawy
- Formerly School of Health Sciences, Cardiff Metropolitan University, Cardiff CF5 2YB, UK
| | - Richard O. Williams
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford OX3 7FY, UK;
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2
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Pires AS, Gupta S, Barton SA, Vander Wall R, Tan V, Heng B, Phillips JK, Guillemin GJ. Temporal Profile of Kynurenine Pathway Metabolites in a Rodent Model of Autosomal Recessive Polycystic Kidney Disease. Int J Tryptophan Res 2022; 15:11786469221126063. [PMID: 36329761 PMCID: PMC9623391 DOI: 10.1177/11786469221126063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 08/27/2022] [Indexed: 11/28/2022] Open
Abstract
Autosomal recessive polycystic kidney disease (ARPKD) is an early onset genetic disorder characterized by numerous renal cysts resulting in end stage renal disease. Our study aimed to determine if metabolic reprogramming and tryptophan (Trp) metabolism via the kynurenine pathway (KP) is a critical dysregulated pathway in PKD. Using the Lewis polycystic kidney (LPK) rat model of PKD and Lewis controls, we profiled temporal trends for KP metabolites in plasma, urine, and kidney tissues from 6- and 12-week-old mixed sex animals using liquid and gas chromatography, minimum n = 5 per cohort. A greater kynurenine (KYN) concentration was observed in LPK kidney and plasma of 12-week rats compared to age matched Lewis controls (P ⩽ .05). LPK kidneys also showed an age effect (P ⩽ .05) with KYN being greater in 12-week versus 6-week LPK. The metabolites xanthurenic acid (XA), 3-hydroxykynurenine (3-HK), and 3-hydroxyanthranilic acid (3-HAA) were significantly greater in the plasma of 12-week LPK rats compared to age matched Lewis controls (P ⩽ .05). Plasma XA and 3-HK also showed an age effect (P ⩽ .05) being greater in 12-week versus 6-week LPK. We further describe a decrease in Trp levels in LPK plasma and kidney (strain effect P ⩽ .05). There were no differences in KP metabolites in urine between cohorts. Using the ratio of product and substrates in the KP, a significant age-strain effect (P ⩽ .05) was observed in the activity of the KYN/Trp ratio (tryptophan-2,3-dioxygenase [TDO] or indoleamine-2,3-dioxygenase [IDO] activity), kynurenine 3-monooxygenase (KMO), KAT A (kynurenine aminotransferase A), KAT B, total KAT, total KYNU (kynureninase), KYNU A, KYNU B, and total KYNU within LPK kidneys, supporting an activated KP. Confirmation of the activation of these enzymes will require verification through orthogonal techniques. In conclusion, we have demonstrated an up-regulation of the KP in alignment with progression of renal impairment in the LPK rat model, suggesting that KP activation may be a critical contributor to the pathobiology of PKD.
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Affiliation(s)
- Ananda Staats Pires
- Neuroinflammation Group, Macquarie
Medical School, Centre for Motor Neuron Disease Research, Faculty of Medicine,
Health and Human Sciences, Macquarie University, Sydney, NSW, Australia,Laboratório de Bioenergética e Estresse
Oxidativo, Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade
Federal de Santa Catarina, Florianópolis, Brasil
| | - Shabarni Gupta
- Autonomic and Sensory Neuroscience
Group, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences,
Macquarie University, Sydney, NSW, Australia
| | - Sean A Barton
- Autonomic and Sensory Neuroscience
Group, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences,
Macquarie University, Sydney, NSW, Australia
| | - Roshana Vander Wall
- Autonomic and Sensory Neuroscience
Group, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences,
Macquarie University, Sydney, NSW, Australia
| | - Vanessa Tan
- Neuroinflammation Group, Macquarie
Medical School, Centre for Motor Neuron Disease Research, Faculty of Medicine,
Health and Human Sciences, Macquarie University, Sydney, NSW, Australia
| | - Benjamin Heng
- Neuroinflammation Group, Macquarie
Medical School, Centre for Motor Neuron Disease Research, Faculty of Medicine,
Health and Human Sciences, Macquarie University, Sydney, NSW, Australia
| | - Jacqueline K Phillips
- Autonomic and Sensory Neuroscience
Group, Macquarie Medical School, Faculty of Medicine, Health and Human Sciences,
Macquarie University, Sydney, NSW, Australia,Jacqueline K Phillips, Autonomic and
Sensory Neuroscience Group, Macquarie Medical School,Department of Biomedical
Science, Faculty of Medicine, Health and Human Sciences, Macquarie University,
Level 1, 75 Talavera Road, Sydney, NSW 2109, Australia.
| | - Gilles J Guillemin
- Neuroinflammation Group, Macquarie
Medical School, Centre for Motor Neuron Disease Research, Faculty of Medicine,
Health and Human Sciences, Macquarie University, Sydney, NSW, Australia
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3
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Marszalek-Grabska M, Walczak K, Gawel K, Wicha-Komsta K, Wnorowska S, Wnorowski A, Turski WA. Kynurenine emerges from the shadows – Current knowledge on its fate and function. Pharmacol Ther 2021; 225:107845. [DOI: 10.1016/j.pharmthera.2021.107845] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 03/29/2021] [Indexed: 12/12/2022]
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4
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Mor A, Kalaska B, Pawlak D. Kynurenine Pathway in Chronic Kidney Disease: What’s Old, What’s New, and What’s Next? Int J Tryptophan Res 2020; 13:1178646920954882. [PMID: 35210786 PMCID: PMC8862190 DOI: 10.1177/1178646920954882] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 08/06/2020] [Indexed: 11/25/2022] Open
Abstract
Impaired kidney function and increased inflammatory process occurring in the course of Chronic Kidney Disease (CKD) contribute to the development of complex amino-acid alterations. The essential amino-acid tryptophan (TRP) undergoes extensive metabolism along several pathways, resulting in the production of many biologically active compounds. The results of many studies have shown that its metabolism via the kynurenine pathway is potently increased in the course of CKD. Metabolites of this pathway exhibit differential, sometimes opposite, roles in several biological processes. Their accumulation in the course of CKD may induce oxidative cell damage which stimulates inflammatory processes. They can also modulate the activity of numerous cellular signaling pathways through activation of the aryl hydrocarbon receptor, leading to the disruption of homeostasis of various organs. As a result, they can contribute to the development of the systemic disorders accompanying the course of chronic renal failure. This review gathers and systematizes reports concerning the knowledge connecting the kynurenine pathway metabolites to systemic disorders accompanying the development of CKD.
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Affiliation(s)
- Adrian Mor
- Department of Pharmacodynamics, Medical University of Bialystok, Bialystok, Poland
| | - Bartlomiej Kalaska
- Department of Pharmacodynamics, Medical University of Bialystok, Bialystok, Poland
| | - Dariusz Pawlak
- Department of Pharmacodynamics, Medical University of Bialystok, Bialystok, Poland
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Podkowińska A, Formanowicz D. Chronic Kidney Disease as Oxidative Stress- and Inflammatory-Mediated Cardiovascular Disease. Antioxidants (Basel) 2020; 9:E752. [PMID: 32823917 PMCID: PMC7463588 DOI: 10.3390/antiox9080752] [Citation(s) in RCA: 135] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/08/2020] [Accepted: 08/10/2020] [Indexed: 12/12/2022] Open
Abstract
Generating reactive oxygen species (ROS) is necessary for both physiology and pathology. An imbalance between endogenous oxidants and antioxidants causes oxidative stress, contributing to vascular dysfunction. The ROS-induced activation of transcription factors and proinflammatory genes increases inflammation. This phenomenon is of crucial importance in patients with chronic kidney disease (CKD), because atherosclerosis is one of the critical factors of their cardiovascular disease (CVD) and increased mortality. The effect of ROS disrupts the excretory function of each section of the nephron. It prevents the maintenance of intra-systemic homeostasis and leads to the accumulation of metabolic products. Renal regulatory mechanisms, such as tubular glomerular feedback, myogenic reflex in the supplying arteriole, and the renin-angiotensin-aldosterone system, are also affected. It makes it impossible for the kidney to compensate for water-electrolyte and acid-base disturbances, which progress further in the mechanism of positive feedback, leading to a further intensification of oxidative stress. As a result, the progression of CKD is observed, with a spectrum of complications such as malnutrition, calcium phosphate abnormalities, atherosclerosis, and anemia. This review aimed to show the role of oxidative stress and inflammation in renal impairment, with a particular emphasis on its influence on the most common disturbances that accompany CKD.
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Affiliation(s)
| | - Dorota Formanowicz
- Department of Clinical Biochemistry and Laboratory Medicine, Poznan University of Medical Sciences, Rokietnicka 8, 60-806 Poznan, Poland
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Chen Y, Xie Z, Xiao C, Zhang M, Li Z, Xie J, Zhang Y, Zhao X, Zeng P, Mo L, Liang X, Shi W. Peripheral kynurenine/tryptophan ratio is not a reliable marker of systemic indoleamine 2,3-dioxygenase: A lesson drawn from patients on hemodialysis. Oncotarget 2018; 8:25261-25269. [PMID: 28445957 PMCID: PMC5421927 DOI: 10.18632/oncotarget.15705] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 01/24/2017] [Indexed: 02/06/2023] Open
Abstract
Indoleamine 2,3-dioxygenase (IDO) has emerged as a pivotal enzyme for mediating immune tolerance. Because IDO metabolizes tryptophan into kynurenine, the plasma kynurenine/tryptophan (Kyn/Trp) ratio has been widely used as a marker of systemic IDO. Here, we evaluated the clinical value of using the plasma Kyn/Trp ratio to estimate cell-mediated immune responses to tuberculin skin testing and risk of new bacterial infection. We also compared the Kyn/Trp ratio to a novel IDO marker, the IDO median fluorescence index (MFI) of peripheral blood mononuclear cells, which was determined by flow cytometry. In 228 patients from two hemodialysis centers, the two IDO markers were higher in patients than in healthy controls but were not correlated with each other. In vitro experiments demonstrated that peripheral blood mononuclear cells could not metabolize tryptophan into kynurenine, indicating that the increased Kyn/Trp ratio was IDO-independent. Skin induration diameters of tuberculin skin testing were correlated with the IDO MFI (negatively), but not the Kyn/Trp ratio. Further, in a 24-month prospective cohort, the Kyn/Trp ratio was not correlated with clinical infection. Alternatively, patients with a higher IDO MFI had a lower accumulative infection-free survival rate. Using a Cox proportional hazard model, it was also revealed that a higher IDO MFI was significantly associated with new bacterial infection. Taken together, these results indicate that the Kyn/Trp ratio is not a reliable circulating IDO marker in hemodialysis patients. However, the IDO MFI reflects an immunocompromised state and thus might be a potential clinical marker of bacterial infection.
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Affiliation(s)
- Yuanhan Chen
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Zhen Xie
- Department of Dermatology, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu, China
| | - Chenggen Xiao
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.,Division of Nephrology, Xiangya Hospital, Central South University, Hunan, China
| | - Min Zhang
- Department of Gastroenterology, The Sixth Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Zhilian Li
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Jianteng Xie
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Yusheng Zhang
- Second Division of Internal Medicine, Wuhua People's Hospital, Guangdong, China
| | - Xingchen Zhao
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.,Southern Medical University, Guangzhou, China
| | - Pengfei Zeng
- Second Division of Internal Medicine, Wuhua People's Hospital, Guangdong, China
| | - Liyi Mo
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.,Department of Nephrology, Dongguan People's Hospital, Guangdong Province, China
| | - Xinling Liang
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Wei Shi
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
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Decreased percentage of peripheral naïve T cells is independently associated with ischemic stroke in patients on hemodialysis. Int Urol Nephrol 2017; 49:2051-2060. [DOI: 10.1007/s11255-017-1691-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 08/29/2017] [Indexed: 01/09/2023]
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8
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Eleftheriadis T, Pissas G, Sounidaki M, Antoniadi G, Rountas C, Liakopoulos V, Stefanidis L. Tryptophan depletion under conditions that imitate insulin resistance enhances fatty acid oxidation and induces endothelial dysfunction through reactive oxygen species-dependent and independent pathways. Mol Cell Biochem 2017; 428:41-56. [PMID: 28161804 DOI: 10.1007/s11010-016-2915-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 12/21/2016] [Indexed: 12/25/2022]
Abstract
In atherosclerosis-associated pathologic entities characterized by malnutrition and inflammation, L-tryptophan (TRP) levels are low. Insulin resistance is an independent cardiovascular risk factor and induces endothelial dysfunction by increasing fatty acid oxidation. It is also associated with inflammation and low TRP levels. Low TRP levels have been related to worse cardiovascular outcome. This study evaluated the effect of TRP depletion on endothelial dysfunction under conditions that imitate insulin resistance. Fatty acid oxidation, harmful pathways due to increased fatty acid oxidation, and endothelial dysfunction were assessed in primary human aortic endothelial cells cultured under normal glucose, low insulin conditions in the presence or absence of TRP. TRP depletion activated general control non-derepressible 2 kinase and inhibited aryl hydrocarbon receptor. It increased fatty acid oxidation by increasing expression and activity of carnitine palmitoyltransferase 1. Elevated fatty acid oxidation increased the formation of reactive oxygen species (ROS) triggering the polyol and hexosamine pathways, and enhancing protein kinase C activity and methylglyoxal production. TRP absence inhibited nitric oxide synthase activity in a ROS-dependent way, whereas it increased the expression of ICAM-1 and VCAM-1 in a ROS independent and possibly p53-dependent manner. Thus, TRP depletion, an amino acid whose low levels have been related to worse cardiovascular outcome and to inflammatory atherosclerosis-associated pathologic entities, under conditions that imitate insulin resistance enhances fatty acid oxidation and induces endothelial dysfunction through ROS-dependent and independent pathways. These findings may offer new insights at the molecular mechanisms involved in accelerated atherosclerosis that frequently accompanies malnutrition and inflammation.
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Affiliation(s)
- Theodoros Eleftheriadis
- Department of Nephrology, Medical School, University of Thessaly, Neo Ktirio, Mezourlo Hill, 41110, Larissa, Greece.
| | - Georgios Pissas
- Department of Nephrology, Medical School, University of Thessaly, Neo Ktirio, Mezourlo Hill, 41110, Larissa, Greece
| | - Maria Sounidaki
- Department of Nephrology, Medical School, University of Thessaly, Neo Ktirio, Mezourlo Hill, 41110, Larissa, Greece
| | - Georgia Antoniadi
- Department of Nephrology, Medical School, University of Thessaly, Neo Ktirio, Mezourlo Hill, 41110, Larissa, Greece
| | - Christos Rountas
- Department of Interventional Radiology, Medical School, University of Thessaly, Larissa, Greece
| | - Vassilios Liakopoulos
- Department of Nephrology, Medical School, University of Thessaly, Neo Ktirio, Mezourlo Hill, 41110, Larissa, Greece
| | - Loannis Stefanidis
- Department of Nephrology, Medical School, University of Thessaly, Neo Ktirio, Mezourlo Hill, 41110, Larissa, Greece
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Yilmaz N, Ustundag Y, Kivrak S, Kahvecioglu S, Celik H, Kivrak I, Huysal K. Serum indoleamine 2,3 dioxygenase and tryptophan and kynurenine ratio using the UPLC-MS/MS method, in patients undergoing peritoneal dialysis, hemodialysis, and kidney transplantation. Ren Fail 2016; 38:1300-9. [PMID: 27466137 DOI: 10.1080/0886022x.2016.1209389] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
BACKGROUND The level and activity of indoleamine 2,3-dioxygenase (IDO) and the concentrations of L-tryptophan and its metabolite L-kynurenine were determined in association with various renal diseases. However, there have been no data regarding these parameters in patients on peritoneal dialysis compared to those undergoing hemodialysis or kidney transplantation. METHODS This study investigated the level and activity of IDO and determined oxidative balance by calculating the total oxidant status (TOS), total antioxidant status (TAS), and oxidative stress index (OSI). We enrolled 60 kidney disease patients, including 20 on peritoneal dialysis (PD group), 19 on hemodialysis (HD group), and 21 with kidney transplantation (KT group), as well as 21 control group. RESULTS IDO levels were increased in the PD, HD, and KT groups compared to the control group. The concentration of kynurenine was significantly increased in the PD group compared to the other groups (p < 0.01). The kynurenine/tryptophan ratio was increased in the PD group compared to the other groups (all p < 0.01). TAS levels in the PD and HD groups were significantly decreased compared to the control group (both p < 0.05). TAS levels in the PD group were significantly decreased compared to the KT group. TOS levels in the PD group were higher than in the HD and KT groups. CONCLUSION The results showed that IDO levels were increased in peritoneal dialysis and hemodialysis patients and in renal transplant recipients, while oxidative stress was found to be related to IDO activity and was most increased in the patients on peritoneal dialysis.
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Affiliation(s)
- Nigar Yilmaz
- a Department of Biochemistry, Medical Faculty , Mugla Sitki Kocman University , Mugla , Turkey
| | - Yasemin Ustundag
- b Department of Biochemistry , Bursa Yuksek Ihtisas Education and Research Hospital , Bursa , Turkey
| | - Seyda Kivrak
- c Department of Nutrition and Dietetics, Faculty of Health Sciences , Mugla Sitki Kocman University , Mugla , Turkey
| | - Serdar Kahvecioglu
- d Department of Nephrology , Bursa Yuksek Ihtisas Education and Research Hospital , Bursa , Turkey
| | - Huseyin Celik
- e Department of Nephrology and Organ Transplantation , Acibadem Hospital , Bursa , Turkey
| | - Ibrahim Kivrak
- f Department of Chemistry and Chemical Treatment Techniques, Mugla Vocational School of Higher Education , Mugla Sitki Kocman University , Mugla , Turkey
| | - Kağan Huysal
- b Department of Biochemistry , Bursa Yuksek Ihtisas Education and Research Hospital , Bursa , Turkey
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Wang Q, Liu D, Song P, Zou MH. Tryptophan-kynurenine pathway is dysregulated in inflammation, and immune activation. Front Biosci (Landmark Ed) 2015; 20:1116-43. [PMID: 25961549 DOI: 10.2741/4363] [Citation(s) in RCA: 236] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The kynurenine (Kyn) pathway is the major route for tryptophan (Trp) metabolism, and it contributes to several fundamental biological processes. Trp is constitutively oxidized by tryptophan 2, 3-dioxygenase in liver cells. In other cell types, it is catalyzed by an alternative inducible indoleamine-pyrrole 2, 3-dioxygenase (IDO) under certain pathophysiological conditions, which consequently increases the formation of Kyn metabolites. IDO is up-regulated in response to inflammatory conditions as a novel marker of immune activation in early atherosclerosis. Besides, IDO and the IDO-related pathway are important mediators of the immunoinflammatory responses in advanced atherosclerosis. In particular, Kyn, 3-hydroxykynurenine, and quinolinic acid are positively associated with inflammation, oxidative stress (SOX), endothelial dysfunction, and carotid artery intima-media thickness values in end-stage renal disease patients. Moreover, IDO is a potential novel contributor to vessel relaxation and metabolism in systemic infections, which is also activated in acute severe heart attacks. The Kyn pathway plays a key role in the increased prevalence of cardiovascular disease by regulating inflammation, SOX, and immune activation.
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Affiliation(s)
| | | | | | - Ming-Hui Zou
- Division of Molecular Medicine, Department of Medicine, and Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA,
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11
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Metabolomic analysis of clinical plasma from cerebral infarction patients presenting with blood stasis. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2015; 2015:453423. [PMID: 25834622 PMCID: PMC4365334 DOI: 10.1155/2015/453423] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 02/17/2015] [Accepted: 02/18/2015] [Indexed: 12/18/2022]
Abstract
Blood stasis (BS) is characterized as a disorder of blood circulation. In traditional Korean medicine (TKM), it is viewed as a cause factor of diseases such as multiple sclerosis and stroke. This study investigated differences in the plasma metabolites profiles of subjects displaying BS or non-BS patterns. Thirty-one patients with cerebral infarction diagnosed with BS and an equal number of sex- and age-matched non-BS patients were enrolled. Metabolic profiling was performed using UPLC-MS. The ratio of subjects with a rough pulse and purple coloration of the tongue was higher in patients presenting with BS pattern. Through metabolomics analysis, 82 metabolites that differed significantly between the BS and non-BS pattern were identified, and the two groups were significantly separated using an orthogonal partial least square-discriminant analysis model (P < 0.001). Of these 82 metabolites, acetyl carnitine, leucine, kynurenine, phosphocholine, hexanoyl carnitine, and decanoyl carnitine were present in significantly higher levels in patients with a BS pattern than those with a non-BS pattern. Our results also demonstrated that seven plasma metabolites, including acyl-carnitines and kynurenine, were associated with a BS pattern, suggesting that variant plasma metabolic profiles may serve as a biomarker for diagnosis of BS in patients with cerebral infarction.
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Xiao C, Chen Y, Liang X, Xie Z, Zhang M, Li R, Li Z, Fu X, Yu X, Shi W. A modified HPLC method improves the simultaneous determination of plasma kynurenine and tryptophan concentrations in patients following maintenance hemodialysis. Exp Ther Med 2014; 7:907-910. [PMID: 24669249 PMCID: PMC3961120 DOI: 10.3892/etm.2014.1512] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Accepted: 01/14/2014] [Indexed: 01/20/2023] Open
Abstract
The ratio between plasma kynurenine (Kyn) and tryptophan (Trp) serves as a marker of indoleamine 2,3-dioxygenase, a critical immunomodulatory molecule. Simultaneous detection of the two markers may be performed using high-pressure liquid chromatography (HPLC). However, for uremic patients, the conventional detection method may be affected by a range of accumulated toxins. The current study aimed to establish a method for the simultaneous measurement of Kyn and Trp in patients following maintenance hemodialysis via HPLC-ultraviolet detection. The procedure involved the use of a SinoChrom ODS-BP C18 column (4.6×150 mm; inner diameter, 4.5 μm) and a mobile phase of 15 mmol/l sodium acetate acetic acid solution (containing 5% acetonitrile, pH 4.8). The modified method was verified using plasma samples from 10 healthy controls and 91 maintenance hemodialysis patients. The results demonstrated that the modified method was successful in simultaneously detecting the concentrations of Trp and Kyn in the healthy controls and maintenance hemodialysis patients. The method is simple, fast, accurate and suitable for clinical and research purposes in maintenance hemodialysis patients.
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Affiliation(s)
- Chenggen Xiao
- Nanfang Medical University, Guangzhou, Guandong 510080, P.R. China ; Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guandong 510080, P.R. China
| | - Yuanhan Chen
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guandong 510080, P.R. China
| | - Xinling Liang
- Nanfang Medical University, Guangzhou, Guandong 510080, P.R. China ; Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guandong 510080, P.R. China
| | - Zhen Xie
- Department of Dermatology, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, Sichuan 610000, P.R. China
| | - Min Zhang
- Department of Gastroenterology, The Sixth Affiliated Hospital, Sun Yat-Sen University, Guangzhou, Guangdong 510081, P.R. China
| | - Ruizhao Li
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guandong 510080, P.R. China
| | - Zhilian Li
- Nanfang Medical University, Guangzhou, Guandong 510080, P.R. China ; Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guandong 510080, P.R. China
| | - Xia Fu
- Nanfang Medical University, Guangzhou, Guandong 510080, P.R. China ; Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guandong 510080, P.R. China
| | - Xiyong Yu
- Medical Research Center, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guangdong 510081, P.R. China
| | - Wei Shi
- Division of Nephrology, Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangzhou, Guandong 510080, P.R. China
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Tanaka A, Kato A, Suzuki Y, Suzuki M, Ohmori H, Sumimoto R, Ohdan H. Association of increased indoleamine 2, 3-dioxygenase with impaired natural killer cell activity in hemodialysis patients. Ther Apher Dial 2013; 18:19-23. [PMID: 24499080 DOI: 10.1111/1744-9987.12071] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Indoleamine 2, 3-dioxygenase (IDO) suppresses adaptive immune response. However, there was no study to examine whether IDO activity is associated with immune parameters in dialysis patients. In this study, we estimated serum IDO activity by the kynurenine/tryptophan ratio (KTR), and compared KTR with natural killer (NK) cell activity, soluble interleukin-2 receptor (sIL-2R) and serum levels of trace elements such as selenium (Se) and zinc (Zn) that affect T-cell function in 28 hemodialysis (HD) patients (age: 72 ± 13 years old, time on HD: 79 ± 89 months). NK cell activity was decreased in 35.7% of the patients. KTR values were almost 10-times higher in HD patients (380.81 ± 385.46 mM/M) than those in the referred controls (32.9 ± 9.10 mM/M). KTR was lower in patients with impaired NK cell activity than those without (279 ± 111 vs. 565 ± 603 mM/M, P = 0.07). There was no relationship between KTR and sIL-2R and Zn, while KTR was significantly and negatively correlated with serum Se levels that can impair cellular immunity (r = -0.41, P < 0.05). Our findings suggest that increased IDO activity with Se deficiency may be associated with impaired NK cell function in HD patients.
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Affiliation(s)
- Asuka Tanaka
- Department of Gastroenterological Surgery and Transplant Surgery, Applied Life Sciences, Institute of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan
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Zhao J. Plasma Kynurenic Acid/Tryptophan Ratio: A Sensitive and Reliable Biomarker for the Assessment of Renal Function. Ren Fail 2013; 35:648-53. [DOI: 10.3109/0886022x.2013.790301] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Eleftheriadis T, Yiannaki E, Antoniadi G, Liakopoulos V, Pissas G, Galaktidou G, Stefanidis I. Plasma indoleamine 2,3-dioxygenase and arginase type I may contribute to decreased blood T-cell count in hemodialysis patients. Ren Fail 2012; 34:1118-22. [PMID: 22897519 DOI: 10.3109/0886022x.2012.713297] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Acquired immunity is impaired in hemodialysis (HD) patients, and decreased T-cell number may contribute. Indoleamine 2,3-dioxygenase (IDO) and arginase type I (ARG) catabolize tryptophane and arginine, respectively, and exert proapoptotic and antiproliferative effects on T-cells. Plasma levels of IDO and ARG and their relation to blood T-cell number were evaluated in HD patients. METHODS Thirty-two HD patients and 20 healthy controls participated in the study. Plasma IDO and ARG were measured by means of enzyme-linked immunosorbent assay. T-cell number was assessed by means of flow cytometry. RESULTS IDO concentration was significantly higher in HD patients than in healthy volunteers (44.30 ± 31.83 ng/mL vs. 21.28 ± 26.21 ng/mL, p = 0.009). There was a trend for higher ARG concentration in HD patients (13.43 ± 11.91 ng/mL) than in healthy volunteers (9.56 ± 4.03 ng/mL), which, however, did not reach statistic significance (p = 0.099). Absolute T-cell count was significantly lower in HD patients than in healthy controls (1176.99 ± 567.71 cells/mm3 vs. 1519.85 ± 594.96 cells/mm3, p = 0.040). Absolute blood T-cell number was inversely related to plasma IDO (r = -0.490, p = 0.004) and to plasma ARG (r = -0.387, p = 0.029) concentrations. CONCLUSIONS Plasma IDO and ARG may contribute to decreased blood T-cell count in HD patients.
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Ogawa K, Hara T, Shimizu M, Ninomiya S, Nagano J, Sakai H, Hoshi M, Ito H, Tsurumi H, Saito K, Seishima M, Tanaka T, Moriwaki H. Suppression of azoxymethane-induced colonic preneoplastic lesions in rats by 1-methyltryptophan, an inhibitor of indoleamine 2,3-dioxygenase. Cancer Sci 2012; 103:951-8. [PMID: 22320717 DOI: 10.1111/j.1349-7006.2012.02237.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Revised: 02/03/2012] [Accepted: 02/04/2012] [Indexed: 12/16/2022] Open
Abstract
The escape of preneoplastic cells from the immune system, which is caused by immune tolerance, occurs during the development of several types of tumors. Indoleamine 2,3-dioxygenase (IDO) plays a critical role in the induction of immune tolerance. In the present study we investigated the effects of 1-methyltryptophan (1-MT), an IDO inhibitor, and (-)-epigallocatechin gallate (EGCG), the major catechin in green tea, on the development of azoxymethane (AOM)-induced colonic preneoplastic lesions by focusing on the inhibition of IDO. To induce colonic premalignant lesions, male F344 rats were injected with AOM (20 mg/kg body weight, s.c.) once a week for 2 weeks. They also received 0.2% 1-MT or 0.1% EGCG in their drinking water for 4 weeks, starting 1 week before the first dose of AOM. Both 1-MT and EGCG significantly decreased the total number of aberrant crypt foci and β-catenin-accumulated crypts, which overexpressed IDO protein. Treatment with EGCG decreased IDO mRNA expression in both the colonic epithelium and stroma of rats induced by AOM. The AOM-induced increase in cyclooxygenase-2 mRNA expression in the colonic stroma was significantly decreased by EGCG. Furthermore, AOM-induced increases in IDO activity in the serum and stroma were significantly inhibited by 1-MT and EGCG. Inhibition of IDO activity by 1-MT and EGCG was also observed in cell-free assays. These findings suggest that upregulation of IDO activity is observed in the early stages of colon carcinogenesis and that the use of IDO inhibitors, such as 1-MT and EGCG, which suppress the occurrence of colonic preneoplastic lesions, could be a novel strategy for the chemoprevention of colon cancer.
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Affiliation(s)
- Kengo Ogawa
- First Department of Internal Medicine, Gifu University Graduate School of Medicine, Gifu, Japan
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