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Fontes FL, Rooker SA, Lynn-Barbe JK, Lyons MA, Crans DC, Crick DC. Pyrazinoic acid, the active form of the anti-tuberculosis drug pyrazinamide, and aromatic carboxylic acid analogs are protonophores. Front Mol Biosci 2024; 11:1350699. [PMID: 38414662 PMCID: PMC10896915 DOI: 10.3389/fmolb.2024.1350699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 01/16/2024] [Indexed: 02/29/2024] Open
Abstract
Pyrazinoic acid is the active form of pyrazinamide, a first-line antibiotic used to treat Mycobacterium tuberculosis infections. However, the mechanism of action of pyrazinoic acid remains a subject of debate, and alternatives to pyrazinamide in cases of resistance are not available. The work presented here demonstrates that pyrazinoic acid and known protonophores including salicylic acid, benzoic acid, and carbonyl cyanide m-chlorophenyl hydrazone all exhibit pH-dependent inhibition of mycobacterial growth activity over a physiologically relevant range of pH values. Other anti-tubercular drugs, including rifampin, isoniazid, bedaquiline, and p-aminosalicylic acid, do not exhibit similar pH-dependent growth-inhibitory activities. The growth inhibition curves of pyrazinoic, salicylic, benzoic, and picolinic acids, as well as carbonyl cyanide m-chlorophenyl hydrazone, all fit a quantitative structure-activity relationship (QSAR) derived from acid-base equilibria with R2 values > 0.95. The QSAR model indicates that growth inhibition relies solely on the concentration of the protonated forms of these weak acids (rather than the deprotonated forms). Moreover, pyrazinoic acid, salicylic acid, and carbonyl cyanide m-chlorophenyl hydrazone all caused acidification of the mycobacterial cytoplasm at concentrations that inhibit bacterial growth. Thus, it is concluded that pyrazinoic acid acts as an uncoupler of oxidative phosphorylation and that disruption of proton motive force is the primary mechanism of action of pyrazinoic acid rather than the inhibition of a classic enzyme activity.
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Affiliation(s)
- Fabio L. Fontes
- Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO, United States
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Steven A. Rooker
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Jamie K. Lynn-Barbe
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Michael A. Lyons
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, United States
| | - Debbie C. Crans
- Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO, United States
- Department of Chemistry, Colorado State University, Fort Collins, CO, United States
| | - Dean C. Crick
- Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO, United States
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, United States
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Kim J, Wang J, Ashley DC, Sharma VK, Huang CH. Picolinic Acid-Mediated Catalysis of Mn(II) for Peracetic Acid Oxidation Processes: Formation of High-Valent Mn Species. Environ Sci Technol 2023; 57:18929-18939. [PMID: 37224105 PMCID: PMC10690714 DOI: 10.1021/acs.est.3c00765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 04/17/2023] [Accepted: 05/11/2023] [Indexed: 05/26/2023]
Abstract
Metal-based advanced oxidation processes (AOPs) with peracetic acid (PAA) have been extensively studied to degrade micropollutants (MPs) in wastewater. Mn(II) is a commonly used homogeneous metal catalyst for oxidant activation, but it performs poorly with PAA. This study identifies that the biodegradable chelating ligand picolinic acid (PICA) can significantly mediate Mn(II) activation of PAA for accelerated MP degradation. Results show that, while Mn(II) alone has minimal reactivity toward PAA, the presence of PICA accelerates PAA loss by Mn(II). The PAA-Mn(II)-PICA system removes various MPs (methylene blue, bisphenol A, naproxen, sulfamethoxazole, carbamazepine, and trimethoprim) rapidly at neutral pH, achieving >60% removal within 10 min in clean and wastewater matrices. Coexistent H2O2 and acetic acid in PAA play a negligible role in rapid MP degradation. In-depth evaluation with scavengers and probe compounds (tert-butyl alcohol, methanol, methyl phenyl sulfoxide, and methyl phenyl sulfone) suggested that high-valent Mn species (Mn(V)) is a likely main reactive species leading to rapid MP degradation, whereas soluble Mn(III)-PICA and radicals (CH3C(O)O• and CH3C(O)OO•) are minor reactive species. This study broadens the mechanistic understanding of metal-based AOPs using PAA in combination with chelating agents and indicates the PAA-Mn(II)-PICA system as a novel AOP for wastewater treatment.
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Affiliation(s)
- Juhee Kim
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Junyue Wang
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Daniel C. Ashley
- Department
of Chemistry and Biochemistry, Spelman College, Atlanta, Georgia 30314, United States
| | - Virender K. Sharma
- Department
of Environmental and Occupational Health, School of Public Health, Texas A&M University, College Station, Texas 77843, United States
| | - Ching-Hua Huang
- School
of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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Yang Z, Cui Y, Pan B, Pignatello JJ. Peroxymonosulfate Activation by Fe(III)-Picolinate Complexes for Efficient Water Treatment at Circumneutral pH: Fe(III)/Fe(IV) Cycle and Generation of Oxyl Radicals. Environ Sci Technol 2023; 57:18918-18928. [PMID: 37061925 DOI: 10.1021/acs.est.3c00777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Improving the reactivity of Fe(III) for activating peroxymonosulfate (PMS) at circumneutral pH is critical to propel the iron-activated PMS processes toward practical wastewater treatment but is yet challenging. Here we employed the complexes of Fe(III) with the biodegradable picolinic acid (PICA) to activate PMS for degradation of selected chlorinated phenols, antibiotics, pharmaceuticals, herbicides, and industrial compounds at pH 4.0-6.0. The FeIII-PICA complexes greatly outperformed the ligand-free Fe(III) and other Fe(III) complexes of common aminopolycarboxylate ligands. In the main activation pathway, the key intermediate is a peroxymonosulfate complex, tentatively identified as PICA-FeIII-OOSO3-, which undergoes O-O homolysis or reacts with FeIII-PICA and PMS to yield FeIV=O and SO4•- without the involvement of commonly invoked Fe(II). PICA-FeIII-OOSO3- can also react directly with certain compounds (chlorophenols and sulfamethoxazole). The relative contributions of PICA-FeIII-OOSO3-, FeIV=O, and SO4•- depend on the structure of target compounds. This work sets an eligible example to enhance the reactivity of Fe(III) toward PMS activation by ligands and sheds light on the previously unrecognized role of the metal-PMS complexes in directing the catalytic cycle and decontamination as well.
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Affiliation(s)
- Zhichao Yang
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, PR China
| | - Yaodan Cui
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, PR China
| | - Bingcai Pan
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, PR China
- Research Center for Environmental Nanotechnology (ReCENT), Nanjing University, Nanjing 210023, PR China
| | - Joseph J Pignatello
- Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, Connecticut 06511, United States
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Narayan R, Sharma M, Yadav R, Biji A, Khatun O, Kaur S, Kanojia A, Joy CM, Rajmani R, Sharma PR, Jeyasankar S, Rani P, Shandil RK, Narayanan S, Rao DC, Satchidanandam V, Das S, Agarwal R, Tripathi S. Picolinic acid is a broad-spectrum inhibitor of enveloped virus entry that restricts SARS-CoV-2 and influenza A virus in vivo. Cell Rep Med 2023; 4:101127. [PMID: 37463584 PMCID: PMC10439173 DOI: 10.1016/j.xcrm.2023.101127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 02/06/2023] [Accepted: 06/23/2023] [Indexed: 07/20/2023]
Abstract
The COVID-19 pandemic highlights an urgent need for effective antivirals. Targeting host processes co-opted by viruses is an attractive antiviral strategy with a high resistance barrier. Picolinic acid (PA) is a tryptophan metabolite endogenously produced in mammals. Here, we report the broad-spectrum antiviral activity of PA against enveloped viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza A virus (IAV), flaviviruses, herpes simplex virus, and parainfluenza virus. Mechanistic studies reveal that PA inhibits enveloped virus entry by compromising viral membrane integrity, inhibiting virus-cellular membrane fusion, and interfering with cellular endocytosis. More importantly, in pre-clinical animal models, PA exhibits promising antiviral efficacy against SARS-CoV-2 and IAV. Overall, our data establish PA as a broad-spectrum antiviral with promising pre-clinical efficacy against pandemic viruses SARS-CoV-2 and IAV.
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Affiliation(s)
- Rohan Narayan
- Emerging Viral Pathogens Laboratory, Infosys Wing, Centre for Infectious Disease Research, Indian Institute of Science, Bengaluru 560012, India; Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru 560012, India
| | - Mansi Sharma
- Emerging Viral Pathogens Laboratory, Infosys Wing, Centre for Infectious Disease Research, Indian Institute of Science, Bengaluru 560012, India; Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru 560012, India
| | - Rajesh Yadav
- Emerging Viral Pathogens Laboratory, Infosys Wing, Centre for Infectious Disease Research, Indian Institute of Science, Bengaluru 560012, India; Centre for BioSystems Science and Engineering, Indian Institute of Science, Bengaluru 560012, India
| | - Abhijith Biji
- Emerging Viral Pathogens Laboratory, Infosys Wing, Centre for Infectious Disease Research, Indian Institute of Science, Bengaluru 560012, India; Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru 560012, India
| | - Oyahida Khatun
- Emerging Viral Pathogens Laboratory, Infosys Wing, Centre for Infectious Disease Research, Indian Institute of Science, Bengaluru 560012, India; Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru 560012, India
| | - Sumandeep Kaur
- Emerging Viral Pathogens Laboratory, Infosys Wing, Centre for Infectious Disease Research, Indian Institute of Science, Bengaluru 560012, India; Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru 560012, India
| | - Aditi Kanojia
- Emerging Viral Pathogens Laboratory, Infosys Wing, Centre for Infectious Disease Research, Indian Institute of Science, Bengaluru 560012, India; Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru 560012, India
| | - Christy Margrat Joy
- Emerging Viral Pathogens Laboratory, Infosys Wing, Centre for Infectious Disease Research, Indian Institute of Science, Bengaluru 560012, India; Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru 560012, India
| | - Raju Rajmani
- Molecular Biophysics Unit, Indian Institute of Science, Bengaluru 560012, India
| | - Pallavi Raj Sharma
- Centre for BioSystems Science and Engineering, Indian Institute of Science, Bengaluru 560012, India
| | - Sharumathi Jeyasankar
- Centre for BioSystems Science and Engineering, Indian Institute of Science, Bengaluru 560012, India
| | - Priya Rani
- Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru 560012, India
| | - Radha Krishan Shandil
- Foundation for Neglected Disease Research, KIADB Industrial Area, Doddaballapur, Bengaluru 561203, India
| | - Shridhar Narayanan
- Foundation for Neglected Disease Research, KIADB Industrial Area, Doddaballapur, Bengaluru 561203, India
| | - Durga Chilakalapudi Rao
- Department of Biological Sciences, School of Engineering and Sciences, SRM University, Andhra Pradesh 522240, India
| | - Vijaya Satchidanandam
- Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru 560012, India
| | - Saumitra Das
- Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru 560012, India
| | - Rachit Agarwal
- Centre for BioSystems Science and Engineering, Indian Institute of Science, Bengaluru 560012, India
| | - Shashank Tripathi
- Emerging Viral Pathogens Laboratory, Infosys Wing, Centre for Infectious Disease Research, Indian Institute of Science, Bengaluru 560012, India; Department of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bengaluru 560012, India.
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Hawrysh PJ, Gao J, Tan S, Oh A, Nodwell J, Tompkins TA, McQuibban GA. PRKN/parkin-mediated mitophagy is induced by the probiotics Saccharomyces boulardii and Lactococcus lactis. Autophagy 2023; 19:2094-2110. [PMID: 36708254 PMCID: PMC10283409 DOI: 10.1080/15548627.2023.2172873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 01/19/2023] [Accepted: 01/20/2023] [Indexed: 01/29/2023] Open
Abstract
Mitochondrial impairment is a hallmark feature of neurodegenerative disorders, such as Parkinson disease, and PRKN/parkin-mediated mitophagy serves to remove unhealthy mitochondria from cells. Notably, probiotics are used to alleviate several symptoms of Parkinson disease including impaired locomotion and neurodegeneration in preclinical studies and constipation in clinical trials. There is some evidence to suggest that probiotics can modulate mitochondrial quality control pathways. In this study, we screened 49 probiotic strains and tested distinct stages of mitophagy to determine whether probiotic treatment could upregulate mitophagy in cells undergoing mitochondrial stress. We found two probiotics, Saccharomyces boulardii and Lactococcus lactis, that upregulated mitochondrial PRKN recruitment, phospho-ubiquitination, and MFN degradation in our cellular assays. Administration of these strains to Drosophila that were exposed to paraquat, a mitochondrial toxin, resulted in improved longevity and motor function. Further, we directly observed increased lysosomal degradation of dysfunctional mitochondria in the treated Drosophila brains. These effects were replicated in vitro and in vivo with supra-physiological concentrations of exogenous soluble factors that are released by probiotics in cultures grown under laboratory conditions. We identified methyl-isoquinoline-6-carboxylate as one candidate molecule, which upregulates mitochondrial PRKN recruitment, phospho-ubiquitination, MFN degradation, and lysosomal degradation of damaged mitochondria. Addition of methyl-isoquinoline-6-carboxylate to the fly food restored motor function to paraquat-treated Drosophila. These data suggest a novel mechanism that is facilitated by probiotics to stimulate mitophagy through a PRKN-dependent pathway, which could explain the potential therapeutic benefit of probiotic administration to patients with Parkinson disease.
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Affiliation(s)
| | - Jinghua Gao
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Stephanie Tan
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Amy Oh
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Justin Nodwell
- Department of Biochemistry, University of Toronto, Toronto, ON, Canada
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Feng T, Liu Q, Xu ZY, Li HT, Wei W, Shi RC, Zhang L, Cao YM, Liu SZ. Design, Synthesis, Herbicidal Activity, and Structure-Activity Relationship Study of Novel 6-(5-Aryl-Substituted-1-Pyrazolyl)-2- Picolinic Acid as Potential Herbicides. Molecules 2023; 28. [PMID: 36771096 DOI: 10.3390/molecules28031431] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 01/18/2023] [Accepted: 01/30/2023] [Indexed: 02/05/2023] Open
Abstract
Picolinic acid and picolinate compounds are a remarkable class of synthetic auxin herbicides. In recent years, two new picolinate compounds, halauxifen-methyl (ArylexTM active) and florpyrauxifen-benzyl (RinskorTM active), have been launched as novel herbicides. Using their structural skeleton as a template, 33 4-amino-3,5-dicholor-6-(5-aryl-substituted-1-pytazolyl)-2-picolinic acid compounds were designed and synthesized for the discovery of compounds with potent herbicidal activity. The compounds were tested for inhibitory activity against the growth of Arabidopsis thaliana roots, and the results demonstrated that the IC50 value of compound V-7 was 45 times lower than that of the halauxifen-methyl commercial herbicide. Molecular docking analyses revealed that compound V-7 docked with the receptor auxin-signaling F-box protein 5 (AFB5) more intensively than picloram. An adaptive three-dimensional quantitative structure-activity relationship model was constructed from these IC50 values to guide the next step of the synthetic strategy. Herbicidal tests of the new compounds indicated that compound V-8 exhibited better post-emergence herbicidal activity than picloram at a dosage of 300 gha-1, and it was also safe for corn, wheat, and sorghum at this dosage. These results demonstrated that 6-(5-aryl-substituted-1-pyrazolyl)-2-picolinic acid compounds could be used as potential lead structures in the discovery of novel synthetic auxin herbicides.
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Fathi M, Vakili K, Yaghoobpoor S, Tavasol A, Jazi K, Mohamadkhani A, Klegeris A, McElhinney A, Mafi Z, Hajiesmaeili M, Sayehmiri F. Dynamic changes in kynurenine pathway metabolites in multiple sclerosis: A systematic review. Front Immunol 2022; 13:1013784. [PMID: 36426364 PMCID: PMC9680557 DOI: 10.3389/fimmu.2022.1013784] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Accepted: 10/04/2022] [Indexed: 11/05/2022] Open
Abstract
Background Multiple sclerosis (MS) is a debilitating neurodegenerative disorder characterized by axonal damage, demyelination, and perivascular inflammatory lesions in the white matter of the central nervous system (CNS). Kynurenine pathway (KP), which is the major route of tryptophan (TRP) metabolism, generates a variety of neurotoxic as well as neuroprotective compounds, affecting MS pathology and the severity of impairments. Alterations in KP have been described not only in MS, but also in various psychiatric and neurodegenerative diseases. The purpose of this systematic review is to investigate the previously reported dysregulation of KP and differences in its metabolites and enzymes in patients with MS compared to healthy control subjects. Method Electronic databases of PubMed, Scopus, Cochrane Database of Systematic Reviews, and Web of Science were searched to identify studies measuring concentrations of KP metabolites and enzymes in MS patients and control subjects. The following metabolites and enzymes implicated in the KP were investigated: TRP, kynurenine (KYN), kynurenic acid (KYNA), quinolinic acid (QUIN), picolinic acid (PIC), hydroxyindoleacetic acid (HIAA), indoleamine 2,3-dioxygenase (IDO), kynurenine aminotransferase (KAT), and their related ratios. Result Ten studies were included in our systematic review. Our review demonstrates that IDO expression is reduced in the peripheral blood mononuclear cells (PBMCs) of MS patients compared to healthy controls. Also, increased levels of QUIN and QUIN/KYNA in the serum and cerebrospinal fluid (CSF) of MS patients is observed. Differences in levels of other metabolites and enzymes of KP are also reported in some of the reviewed studies, however there are discrepancies among the included reports. Conclusion The results of this investigation suggest a possible connection between alterations in the levels of KP metabolite or enzymes and MS. QUIN levels in CSF were higher in MS patients than in healthy controls, suggesting that QUIN may be involved in the pathogenesis of MS. The data indicate that differences in the serum/blood or CSF levels of certain KP metabolites and enzymes could potentially be used to differentiate between MS patients and control subjects.
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Affiliation(s)
- Mobina Fathi
- Student Research Committee, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Kimia Vakili
- Student Research Committee, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Shirin Yaghoobpoor
- Student Research Committee, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Arian Tavasol
- Student Research Committee, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Kimia Jazi
- Faculty of Medicine, Medical University of Qom, Qom, Iran
| | - Ashraf Mohamadkhani
- Liver and Pancreatobiliary Diseases Research Center, Digestive Disease Research Institute, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Andis Klegeris
- Department of Biology, Faculty of Science, University of British Columbia, Kelowna, BC, Canada
| | - Alyssa McElhinney
- Department of Biology, Faculty of Science, University of British Columbia, Kelowna, BC, Canada
| | - Zahedeh Mafi
- Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammadreza Hajiesmaeili
- Critical Care Quality Improvement Research Center, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Fatemeh Sayehmiri
- Student Research Committee, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Iikuni S, Tarumizu Y, Tsuchihashi S, Ohara T, Watanabe H, Ono M. Synthesis and Evaluation of Novel 111In-Labeled Picolinic Acid-Based Radioligands Containing an Albumin Binder for Development of a Radiotheranostic Platform. Mol Pharm 2022; 19:2725-2736. [PMID: 35758049 DOI: 10.1021/acs.molpharmaceut.2c00071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Picolinic acid-based metallic chelators, e.g., neunpa and octapa, have attracted much attention as promising scaffolds for radiotheranostic agents, particularly those containing larger α-emitting radiometals. Furthermore, albumin binder (ALB) moieties, which noncovalently bind to albumin, have been utilized to improve the pharmacokinetics of radioligands targeting various biomolecules. In this study, we designed and synthesized novel neunpa and octapa derivatives (Neunpa-2 and Octapa-2, respectively), which contained a prostate-specific membrane antigen (PSMA)-binding moiety (model targeting vector) and an ALB moiety. We evaluated the fundamental properties of these derivatives as radiotheranostic agents using 111In. In a cell-binding assay using LNCaP (PSMA-positive) cells, [111In]In-Neunpa-2 and [111In]In-Octapa-2 specifically bound to the LNCaP cells. In addition, a human serum albumin (HSA)-binding assay revealed that [111In]In-Neunpa-2 and [111In]In-Octapa-2 exhibited greater binding to HSA than their non-ALB-conjugated counterparts ([111In]In-Neunpa-1 and [111In]In-Octapa-1, respectively). A biodistribution assay conducted in LNCaP tumor-bearing mice showed that the introduction of the ALB moiety into the 111In-labeled neunpa and octapa derivatives resulted in markedly enhanced tumor uptake and retention of the radioligands. Furthermore, single-photon emission computed tomography imaging of LNCaP tumor-bearing mice with [111In]In-Octapa-2 produced tumor images. These results indicate that [111In]In-Octapa-2 may be a useful PSMA imaging probe and that picolinic acid-based ALB-conjugated radiometallic complexes may be promising candidates as radiotheranostic agents.
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Affiliation(s)
- Shimpei Iikuni
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 606-8501 Kyoto, Japan
| | - Yuta Tarumizu
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 606-8501 Kyoto, Japan
| | - Shohei Tsuchihashi
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 606-8501 Kyoto, Japan
| | - Takaki Ohara
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 606-8501 Kyoto, Japan
| | - Hiroyuki Watanabe
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 606-8501 Kyoto, Japan
| | - Masahiro Ono
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 606-8501 Kyoto, Japan
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Xu S, Wang X, Zhang F, Jiang Y, Zhang Y, Cheng M, Yan X, Hong Q, He J, Qiu J. PicR as a MarR Family Transcriptional Repressor Multiply Controls the Transcription of Picolinic Acid Degradation Gene Cluster pic in Alcaligenes faecalis JQ135. Appl Environ Microbiol 2022;:e0017222. [PMID: 35604228 DOI: 10.1128/aem.00172-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Picolinic acid (PA) is a natural toxic pyridine derivative as well as an important intermediate used in the chemical industry. In a previous study, we identified a gene cluster, pic, that responsible for the catabolism of PA in Alcaligenes faecalis JQ135. However, the transcriptional regulation of the pic cluster remains known. This study showed that the entire pic cluster was composed of 17 genes and transcribed as four operons: picR, picCDEF, picB4B3B2B1, and picT1A1A2A3T2T3MN. Deletion of picR, encoding a putative MarR-type regulator, greatly shortened the lag phase of PA degradation. An electrophoretic mobility shift assay and DNase I footprinting showed that PicR has one binding site in the picR-picC intergenic region and two binding sites in the picB-picT1 intergenic region. The DNA sequences of the three binding sites have the palindromic characteristics of TCAG-N4-CTNN: the space consists of four nonspecific bases, and the four palindromic bases on the left and the first two palindromic bases on the right are strictly conserved, while the last two bases on the right vary among the three binding sites. An in vivo β-galactosidase activity reporter assay indicated that 6-hydroxypicolinic acid but not PA acted as a ligand of PicR, preventing PicR from binding to promoter regions and thus derepressing the transcription of the pic cluster. This study revealed the negative transcriptional regulation mechanism of PA degradation by PicR in A. faecalis JQ135 and provides new insights into the structure and function of the MarR-type regulator. IMPORTANCE The pic gene cluster was found to be responsible for PA degradation and widely distributed in Alpha-, Beta-, and Gammaproteobacteria. Thus, it is very necessary to understand the regulation mechanism of the pic cluster in these strains. This study revealed that PicR binds to three sites of the promoter regions of the pic cluster to multiply regulate the transcription of the pic cluster, which enables A. faecalis JQ135 to efficiently utilize PA. Furthermore, the study also found a unique palindrome sequence for binding of the MarR-type regulator. This study enhanced our understanding of microbial catabolism of environmental toxic pyridine derivatives.
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10
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Kim J, Wang J, Ashley DC, Sharma VK, Huang CH. Enhanced Degradation of Micropollutants in a Peracetic Acid-Fe(III) System with Picolinic Acid. Environ Sci Technol 2022; 56:4437-4446. [PMID: 35319885 DOI: 10.1021/acs.est.1c08311] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Activation of peracetic acid (PAA) with iron species is an emerging advanced oxidation process (AOP). This study investigates the use of the chelating agent picolinic acid (PICA) to extend the pH range and enhance the performance of the PAA-Fe(III) AOP. Compared to the PAA-Fe(III) system, the PAA-Fe(III)-PICA system degrades various micropollutants (MPs: methylene blue, naproxen, sulfamethoxazole, carbamazepine, trimethoprim, diclofenac, and bisphenol-A) much more rapidly at higher pH, achieving almost complete removal of parent compounds within 10 min. PAA significantly outperforms the coexistent H2O2 and is the key oxidant for rapid compound degradation. Other chelating agents, EDTA, NTA, citric acid, proline, and nicotinic acid, could not enhance MP degradation in the PAA-Fe(III) system, while 2,6-pyridinedicarboxylic acid with a structure similar to PICA moderately enhanced MP degradation. Experiments with scavengers (tert-butyl alcohol and methyl phenyl sulfoxide) and a probe compound (benzoic acid) confirmed that high-valent iron species [Fe(IV) and/or Fe(V)], rather than radicals, are the major reactive species contributing to MP degradation. The oxidation products of methylene blue, naproxen, and sulfamethoxazole by PAA-Fe(III)-PICA were characterized and supported the proposed mechanism. This work demonstrates that PICA is an effective complexing ligand to assist the Fenton reaction of PAA by extending the applicable pH range and accelerating the catalytic ability of Fe(III).
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Affiliation(s)
- Juhee Kim
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Junyue Wang
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Daniel C Ashley
- Department of Chemistry and Biochemistry, Spelman College, Atlanta, Georgia 30314, United States
| | - Virender K Sharma
- Department of Environmental and Occupational Health, School of Public Health, Texas A&M University, College Station, Texas 77843, United States
| | - Ching-Hua Huang
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
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11
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Porter GA, O’Connor JC. Chronic Unpredictable Stress Alters Brain Tryptophan Metabolism and Impairs Working Memory in Mice without Causing Depression-Like Behaviour. Neurol Neurobiol (Tallinn) 2021; 4:10.31487/j.nnb.2021.03.03. [PMID: 35662811 PMCID: PMC9164423 DOI: 10.31487/j.nnb.2021.03.03] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Chronic stress is a well-known risk factor in major depressive disorder and disrupts the kynurenine and serotonin pathways of tryptophan metabolism. Here, we characterize the temporal central and peripheral changes in tryptophan metabolism and concomitant depressive-like behavioural phenotype induced during the progression of chronic unpredictable stress (CUS). Mice were exposed to 0, 10, 20, or 30 days of CUS followed by a panel of behavioural assays to determine depressive-like phenotypes. Immediately after behavioural testing, plasma and brain tissue were collected for metabolic analysis. While anhedonia-like and anxiety-like behaviours were unaffected by stress, nesting behaviour and cognitive deficits became apparent in response to CUS exposure. While CUS caused a transient reduction in circulating quinolinic acid, no other tryptophan metabolites significantly changed in response to CUS. In the brain, tryptophan, kynurenine, picolinic acid, and 5-hydroxyindoleacetic acid concentrations were significantly elevated in CUS-exposed mice compared with non-stress control animals, while kynurenic acid, xanthurenic acid, and serotonin decreased in CUS-exposed mice. Metabolic turnover of serotonin to the major metabolite 5- hydroxyindoleacetic acid was markedly increased in response to CUS. These results suggest that CUS impairs hippocampal-dependent working memory and enhances nascent nesting behaviour in C57BL/6J male mice, and these behaviours are associated with increased brain kynurenine pathway metabolism leading to accumulation of picolinic acid and a significant reduction in serotonin levels.
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Affiliation(s)
- Grace A. Porter
- Department of Pharmacology, UT Health San Antonio, San Antonio, Texas, USA
- Center for Biomedical Neuroscience, UT Health San Antonio, San Antonio, Texas, USA
| | - Jason C. O’Connor
- Audie L. Murphy VA Hospital, South Texas Veterans Health System, San Antonio, Texas, USA
- Department of Pharmacology, UT Health San Antonio, San Antonio, Texas, USA
- Center for Biomedical Neuroscience, UT Health San Antonio, San Antonio, Texas, USA
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12
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Soldin Ž, Kukovec BM, Matković-Čalogović D, Popović Z. The Solvent Effect on Composition and Dimensionality of Mercury(II) Complexes with Picolinic Acid. Molecules 2021; 26:molecules26165002. [PMID: 34443586 PMCID: PMC8400068 DOI: 10.3390/molecules26165002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/30/2021] [Accepted: 08/14/2021] [Indexed: 11/25/2022] Open
Abstract
Three new mercury(II) coordination compounds, {[HgCl(pic)]}n (1), [HgCl(pic)(picH)] (2), and [HgBr(pic)(picH)] (3) (picH = pyridine-2-carboxylic acid, picolinic acid) were prepared by reactions of the corresponding mercury(II) halides and picolinic acid in an aqueous (1) or alcohol–methanol or ethanol (2 and 3) solutions. Two different types of coordination compounds were obtained depending on the solvent used. The crystal structures were determined by the single-crystal X-ray structural analysis. Compound 1 is a one-dimensional (1-D) coordination polymer with mercury(II) ions bridged by chelating and bridging N,O,O′-picolinate ions. Each mercury(II) ion is four-coordinated with a bidentate picolinate ion, a carboxylate O atom from the symmetry-related picolinate ion and with a chloride ion; the resulting coordination environment can be described as a highly distorted tetrahedron. Compounds 2 and 3 are isostructural mononuclear coordination compounds, each mercury(II) ion being coordinated with the respective halide ion, N,O-bidentate picolinate ion, and N,O-bidentate picolinic acid in a highly distorted square-pyramidal coordination environment. Compounds 1–3 were characterized by IR spectroscopy, PXRD, and thermal methods (TGA/DSC) in the solid state and by 1H and 13C NMR spectroscopy in the DMSO solution.
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Affiliation(s)
- Željka Soldin
- Division of General and Inorganic Chemistry, Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, HR-10000 Zagreb, Croatia; (D.M.-Č.); (Z.P.)
- Correspondence: (Ž.S.); (B.-M.K.)
| | - Boris-Marko Kukovec
- Department of Physical Chemistry, Faculty of Chemistry and Technology, University of Split, Ruđera Boškovića 35, HR-21000 Split, Croatia
- Correspondence: (Ž.S.); (B.-M.K.)
| | - Dubravka Matković-Čalogović
- Division of General and Inorganic Chemistry, Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, HR-10000 Zagreb, Croatia; (D.M.-Č.); (Z.P.)
| | - Zora Popović
- Division of General and Inorganic Chemistry, Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, HR-10000 Zagreb, Croatia; (D.M.-Č.); (Z.P.)
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13
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Yang Z, Shan C, Pan B, Pignatello JJ. The Fenton Reaction in Water Assisted by Picolinic Acid: Accelerated Iron Cycling and Co-generation of a Selective Fe-Based Oxidant. Environ Sci Technol 2021; 55:8299-8308. [PMID: 34032409 DOI: 10.1021/acs.est.1c00230] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The Fenton reaction is limited by a narrow acidic pH range, the slow reduction of Fe(III), and susceptibility of the nonselective hydroxyl radical (HO•) to scavenging by water constituents. Here, we employed the biodegradable chelating agent picolinic acid (PICA) to address these concerns. Compared to the classical Fenton reaction at pH 3.0, PICA greatly accelerated the degradation of atrazine, sulfamethazine, and various substituted phenols at pH 5.0 in a reaction with autocatalytic characteristics. Although HO• served as the principal oxidant, a high-spin, end-on hydroperoxo intermediate, tentatively identified as PICA-FeIII-OOH, also exhibited reactivity toward several test compounds. Chloride release from the oxidation of 2,4,6-trichlorophenol and the positive slope of the Hammett correlation for a series of halogenated phenols were consistent with PICA-FeIII-OOH reacting as a nucleophilic oxidant. Compared to HO•, PICA-FeIII-OOH is less sensitive to potential scavengers in environmental water samples. Kinetic analysis reveals that PICA facilitates Fe(III)/Fe(II) transformation by accelerating Fe(III) reduction by H2O2. Autocatalysis is ascribed to the buildup of Fe(II) from the reduction of Fe(III) by H2O2 as well as PICA oxidation products. PICA assistance in the Fenton reaction may be beneficial to wastewater treatment because it favors iron cycling, extends the pH range, and balances oxidation universality with selectivity.
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Affiliation(s)
- Zhichao Yang
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, PR China
- Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, Connecticut 06511, United States
| | - Chao Shan
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, PR China
- Research Center for Environmental Nanotechnology (ReCENT), Nanjing University, Nanjing 210023, PR China
| | - Bingcai Pan
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, PR China
- Research Center for Environmental Nanotechnology (ReCENT), Nanjing University, Nanjing 210023, PR China
| | - Joseph J Pignatello
- Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, Connecticut 06511, United States
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14
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Evtushenko DN, Arkhipov SG, Fateev AV, Izaak TI, Egorova LA, Skorik NA, Vodyankina OV, Boldyreva EV. A cocrystal of L-ascorbic acid with picolinic acid: the role of O-H...O, N-H...O and C-H...O hydrogen bonds and L-ascorbic acid conformation in structure stabilization. Acta Crystallogr B Struct Sci Cryst Eng Mater 2020; 76:967-978. [PMID: 33289709 DOI: 10.1107/s2052520620012421] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 09/09/2020] [Indexed: 06/12/2023]
Abstract
A new 1:1 cocrystal (L-Asc-Pic) of L-ascorbic acid (vitamin C) with picolinic acid was prepared as a powder and as single crystals. The crystal structure was solved and refined from single-crystal X-ray diffraction (SCXRD) data collected at 293 (2) and 100 (2) K. The samples of the L-Asc-Pic cocrystal were characterized by elemental (HCNS) analysis and titrimetric methods, TG/DTG/DSC, and IR and Raman spectroscopy. The asymmetric unit comprises a picolinic acid zwitterion and an L-ascorbic acid molecule. The stabilization energy of intermolecular interactions involving hydrogen bonds, the vibrational spectrum and the energies of the frontier molecular orbitals were calculated using the GAUSSIAN09 and the CrystalExplorer17 programs. The charge distribution on the atoms of the L-Asc-Pic cocrystal, L-ascorbic acid itself and its 12 known cocrystals (structures from Version 5.40 of the Cambridge Structural Database) were calculated by the methods of Mulliken, Voronoi and Hirshfeld charge analyses (ADF) at the bp86/TZ2P+ level of theory. The total effective charges and conformations of the L-ascorbic acid molecules in the new and previously reported cocrystals were compared with those of the two symmetry-independent molecules in the crystals of L-ascorbic acid. A correlation between molecular conformation and its effective charge is discussed.
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Affiliation(s)
- Diana N Evtushenko
- National Research Tomsk State University, Lenin Ave. 36, Tomsk, 634050, Russian Federation
| | - Sergey G Arkhipov
- Boreskov Institute of Catalysis SB RAS, Lavrentiev Ave. 5, Novosibirsk, 630090, Russian Federation
| | - Alexander V Fateev
- National Research Tomsk State University, Lenin Ave. 36, Tomsk, 634050, Russian Federation
| | - Tatyana I Izaak
- National Research Tomsk State University, Lenin Ave. 36, Tomsk, 634050, Russian Federation
| | - Lidia A Egorova
- National Research Tomsk State University, Lenin Ave. 36, Tomsk, 634050, Russian Federation
| | - Nina A Skorik
- National Research Tomsk State University, Lenin Ave. 36, Tomsk, 634050, Russian Federation
| | - Olga V Vodyankina
- National Research Tomsk State University, Lenin Ave. 36, Tomsk, 634050, Russian Federation
| | - Elena V Boldyreva
- Boreskov Institute of Catalysis SB RAS, Lavrentiev Ave. 5, Novosibirsk, 630090, Russian Federation
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15
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Ferrier MG, Li Y, Chyan MK, Wong R, Li L, Spreckelmeyer S, Hamlin DK, Mastren T, Fassbender ME, Orvig C, Wilbur DS. Thorium chelators for targeted alpha therapy: Rapid chelation of thorium-226. J Labelled Comp Radiopharm 2020; 63:502-516. [PMID: 32812275 DOI: 10.1002/jlcr.3875] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 08/06/2020] [Accepted: 08/06/2020] [Indexed: 12/26/2022]
Abstract
One of the main challenges in targeted alpha therapy is assuring delivery of the α-particle dose to the targeted cells. Thus, it is critical to identify ligands for α-emitting radiometals that will form complexes that are very stable, both in vitro and in vivo. In this investigation, thorium-227 (t1/2 = 18.70 days) chelation of ligands containing hydroxypyridinonate (HOPO) or picolinic acid (pa) moieties and the stability of the resultant complexes were studied. Chelation reactions were followed by reversed-phased HPLC and gamma spectroscopy. Studies revealed that high 227 Th chelation yields could be obtained within 2.5 h or less with ligands containing four Me-3,2-HOPO moieties, 1 (83%) and 2 (65%), and also with ligands containing pa moieties, H4 octapa 3 (65%) and H4 py4pa 6 (87%). No reaction occurred with H4 neunpa-p-Bn-NO2 4, and the chelation reaction with another pa ligand H4 pypa 5 gave inconsistent yields with a very broad radio-HPLC peak. The ligands spermine-(Me-3,2-HOPO)4 1, H4 octapa 3, and H4 py4pa 6 had high stability (i.e., 87% of 227 Th still bound to the ligand) in phosphate-buffered saline at room temperature over a 6-day period. Preliminary studies with ligand 6 demonstrated efficient chelation of thorium-226 (t1/2 = 30.57 min) when heated to 80°C for 5 min.
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Affiliation(s)
- Maryline G Ferrier
- Department of Radiation Oncology, University of Washington, Seattle, Washington, USA.,Nuclear and Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, California, USA
| | - Yawen Li
- Department of Radiation Oncology, University of Washington, Seattle, Washington, USA
| | - Ming-Kuan Chyan
- Department of Radiation Oncology, University of Washington, Seattle, Washington, USA
| | - Roger Wong
- Department of Radiation Oncology, University of Washington, Seattle, Washington, USA
| | - Lily Li
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada.,Life Sciences Division, TRIUMF, Vancouver, British Columbia, Canada
| | - Sarah Spreckelmeyer
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada
| | - Donald K Hamlin
- Department of Radiation Oncology, University of Washington, Seattle, Washington, USA
| | - Tara Mastren
- Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
| | | | - Chris Orvig
- Medicinal Inorganic Chemistry Group, Department of Chemistry, University of British Columbia, Vancouver, British Columbia, Canada
| | - D Scott Wilbur
- Department of Radiation Oncology, University of Washington, Seattle, Washington, USA
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16
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Schwieler L, Trepci A, Krzyzanowski S, Hermansson S, Granqvist M, Piehl F, Venckunas T, Brazaitis M, Kamandulis S, Lindqvist D, Jones AD, Erhardt S, Brundin L. A novel, robust method for quantification of multiple kynurenine pathway metabolites in the cerebrospinal fluid. Bioanalysis 2020; 12:379-92. [PMID: 32209024 DOI: 10.4155/bio-2019-0303] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Aim: Kynurenine metabolites are potential modulators of psychiatric disease. We aimed to develop a highly sensitive biochemical analysis of cerebrospinal fluid (CSF) tryptophan (TRP) metabolites, to investigate the stability of metabolites and to confirm our previous findings of aberrant CSF quinolinic acid (QUIN) and picolinic acid (PIC) in suicide attempters using this method. Methodology & results: Ten CSF TRP metabolites were analyzed with ultraperformance LC–MS/MS. The method showed small intra- and interassay variation. Metabolites were stable following freeze–thaw cycles. A decreased CSF PIC/QUIN ratio was found in suicide attempters. Conclusion: The feasibility of reliably determining CSF TRP metabolites were demonstrated, including separation of the two isomers PIC and nicotinic acid (NA) and the finding of a reduced PIC/QUIN ratio replicated in suicide attempters.
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17
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Santisukwongchote K, Amornlertwatana Y, Sastraruji T, Jaikang C. Possible Use of Blood Tryptophan Metabolites as Biomarkers for Coronary Heart Disease in Sudden Unexpected Death. Metabolites 2019; 10:E6. [PMID: 31861670 PMCID: PMC7022541 DOI: 10.3390/metabo10010006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 11/22/2019] [Accepted: 12/17/2019] [Indexed: 11/28/2022] Open
Abstract
Coronary heart disease (CHD) is the major cause of death in sudden unexpected death (SUD) cases. Tryptophan (TRP) and its metabolites are correlated with the CHD patient but less studies in the SUD. The aim of this study was to evaluate the relationship of TRP and its metabolites with the CHD in the SUD cases. Blood samples and heart tissues were collected from CHD subjects (n = 31) and the control group (n = 72). Levels of kynurenine (KYN), kynurenic acid (KYA), xanthurenic acid (XAN), 3-hydroxyanthranillic acid (HAA), quinolinic acid (QA), picolinic acid (PA) and 5-hydroxyindoleacetic acid (HIAA) were determined by HPLC-DAD. A severity of heart occlusion was categorized into four groups, and the relationship was measured with the TRP metabolites. The HIAA and The KYN levels significantly differed (p < 0.01) between the CHD group and the control group. Lower levels of QA/XAN, PA/KA, HAA/XAN, KYN/XAN and KYN/TRP were found in the CHD group. However, PA/HAA, PA/HIAA, PA/KYN and XAN/KA values in the CHD group were higher than the control group (p < 0.05). This study revealed that the values of PA/KA and PA/HAA provided better choices for a CHD biomarker in postmortem bodies.
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Affiliation(s)
- Kobchai Santisukwongchote
- Department of Forensic Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand;
| | - Yutti Amornlertwatana
- Department of Forensic Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand;
| | - Thanapat Sastraruji
- Center of Excellence in Oral and Maxillofacial Biology, Faculty of Dentistry, Chiang Mai University, Chiang Mai 50200, Thailand;
| | - Churdsak Jaikang
- Department of Forensic Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai 50200, Thailand;
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18
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Ervik AO, Solvang SEH, Nordrehaug JE, Ueland PM, Midttun Ø, Hildre A, McCann A, Nygård O, Aarsland D, Giil LM. The Associations Between Cognitive Prognosis and Kynurenines Are Modified by the Apolipoprotein ε4 Allele Variant in Patients With Dementia. Int J Tryptophan Res 2019; 12:1178646919885637. [PMID: 31798303 PMCID: PMC6859685 DOI: 10.1177/1178646919885637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Accepted: 10/08/2019] [Indexed: 12/04/2022] Open
Abstract
Background: The apolipoprotein E ε4 gene variant (APOEε4) confers considerable risk for
dementia and affects neuroinflammation, brain metabolism, and synaptic
function. The kynurenine pathway (KP) gives rise to neuroactive metabolites,
which have inflammatory, redox, and excitotoxic effects in the brain. Aim: To assess whether the presence of at least one APOEε4 allele modifies the
association between kynurenines and the cognitive prognosis. Methods: A total of 152 patients with sera for metabolite measurements and APOE
genotype were included from the Dementia Study of Western
Norway. The participants had mild Alzheimer disease and Lewy body dementia.
Apolipoprotein E ε4 gene variant allele status was classified as one or more
ε4 versus any other. Mini-Mental State Examination (MMSE) was measured at
baseline and for 5 consecutive years. Mann-Whitney U tests
and linear mixed-effects models were used for statistical analysis. Results: There were no significant differences in serum concentrations of tryptophan
and kynurenine according to the presence or absence of APOEε4. High serum
concentrations of kynurenic acid, quinolinic acid, and picolinic acid, and a
higher kynurenine-to-tryptophan ratio, were all associated with more
cognitive decline in patients without APOEε4 compared to those with the
APOEε4 allele (P-value of the interactions < .05). Conclusions: Kynurenic acid, quinolinic acid, picolinic acid, and the
kynurenine-to-tryptophan ratio were associated with a significant increase
in cognitive decline when the APOEε4 variant was absent, whereas there was a
relatively less decline when the APOEε4 variant was present.
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Affiliation(s)
- Arne Olav Ervik
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | - Stein-Erik Hafstad Solvang
- Department of Clinical Science, University of Bergen, Bergen, Norway.,Department of Internal Medicine, Haraldsplass Deaconess Hospital, Bergen, Norway
| | - Jan Erik Nordrehaug
- Department of Clinical Science, University of Bergen, Bergen, Norway.,Department of Internal Medicine, Haraldsplass Deaconess Hospital, Bergen, Norway
| | | | | | - Audun Hildre
- Department of Clinical Science, University of Bergen, Bergen, Norway
| | | | - Ottar Nygård
- Department of Internal Medicine, Haraldsplass Deaconess Hospital, Bergen, Norway.,Department of Heart Disease, Haukeland University Hospital, Bergen, Norway
| | - Dag Aarsland
- Department of Old Age Psychiatry, King's College London, London, UK
| | - Lasse Melvaer Giil
- Department of Clinical Science, University of Bergen, Bergen, Norway.,Department of Internal Medicine, Haraldsplass Deaconess Hospital, Bergen, Norway
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19
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Hasse D, Hülsemann J, Carlsson GH, Valegård K, Andersson I. Structure and mechanism of piperideine-6-carboxylate dehydrogenase from Streptomyces clavuligerus. Acta Crystallogr D Struct Biol 2019; 75:1107-1118. [PMID: 31793904 DOI: 10.1107/s2059798319014852] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Accepted: 11/04/2019] [Indexed: 11/11/2022]
Abstract
The core of β-lactam antibiotics originates from amino acids of primary metabolism in certain microorganisms. β-Lactam-producing bacteria, including Streptomyces clavuligerus, synthesize the precursor of the amino acid α-aminoadipic acid by the catabolism of lysine in two steps. The second reaction, the oxidation of piperideine-6-carboxylate (or its open-chain form α-aminoadipate semialdehyde) to α-aminoadipic acid, is catalysed by the NAD+-dependent enzyme piperideine-6-carboxylate dehydrogenase (P6CDH). This structural study, focused on ligand binding and catalysis, presents structures of P6CDH from S. clavuligerus in its apo form and in complexes with the cofactor NAD+, the product α-aminoadipic acid and a substrate analogue, picolinic acid. P6CDH adopts the common aldehyde dehydrogenase fold, consisting of NAD-binding, catalytic and oligomerization domains. The product binds in the oxyanion hole, close to the catalytic residue Cys299. Clear density is observed for the entire cofactor, including the nicotinamide riboside, in the binary complex. NAD+ binds in an extended conformation with its nicotinamide ring overlapping with the binding site of the carboxylate group of the product, implying that the conformation of the cofactor may change during catalysis. The binding site of the substrate analogue overlaps with that of the product, suggesting that the cyclic form of the substrate, piperideine-6-carboxylate, may be accepted as a substrate by the enzyme. The catalytic mechanism and the roles of individual residues are discussed in light of these results.
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Affiliation(s)
- Dirk Hasse
- Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, Husargatan 3, Box 596, SE-751 24 Uppsala, Sweden
| | - Janne Hülsemann
- Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, Husargatan 3, Box 596, SE-751 24 Uppsala, Sweden
| | - Gunilla H Carlsson
- Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, Husargatan 3, Box 596, SE-751 24 Uppsala, Sweden
| | - Karin Valegård
- Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, Husargatan 3, Box 596, SE-751 24 Uppsala, Sweden
| | - Inger Andersson
- Laboratory of Molecular Biophysics, Department of Cell and Molecular Biology, Uppsala University, Husargatan 3, Box 596, SE-751 24 Uppsala, Sweden
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20
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Sampaio-Dias IE, Silva-Reis SC, García-Mera X, Brea J, Loza MI, Alves CS, Algarra M, Rodríguez-Borges JE. Synthesis, Pharmacological, and Biological Evaluation of MIF-1 Picolinoyl Peptidomimetics as Positive Allosteric Modulators of D 2R. ACS Chem Neurosci 2019; 10:3690-3702. [PMID: 31347842 DOI: 10.1021/acschemneuro.9b00259] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
This work describes the synthesis and pharmacological evaluation of picolinoyl-based peptidomimetics of melanocyte stimulating hormone release inhibiting factor 1 (MIF-1) as dopamine modulating agents. Eight novel peptidomimetics were tested for their ability to enhance the maximal effect of tritiated N-propylapomorphine ([3H]-NPA) at dopamine D2 receptors (D2R). Methyl picolinoyl-l-valyl-l-alaninate (compound 6b) produced a statistically significant increase in the maximal [3H]-NPA response at 0.01 nM (11.9 ± 3.7%), which is close to the effect of MIF-1 in this assay at same concentration (18.3 ± 9.1%). Functional assays measuring cAMP mobilization in the presence of dopamine corroborate the activity of peptidomimetic 6b as a positive allosteric modulator (PAM) of D2R. In this assay, 6b produced a typical bell-shaped dose-response curve similar to that of the parent neuropeptide (18.3 ± 7.1% for 6b vs 15.4 ± 5.5% for MIF-1, both at 0.1 nM). Dose-response curves for dopamine in the presence of 6b show EC50 (0.33 ± 0.21 μM for 6b vs 0.17 ± 0.07 μM for MIF-1) and Emax (86.0 ± 5.4% for 6b vs 93.6 ± 4.4% for MIF-1) comparable to those of MIF-1, both at 0.01 nM. Furthermore, peptidomimetic 6b was tested for agonist activity at the human D2R and the results show that it displays no intrinsic agonism effect, endorsing its activity as a PAM of D2R. Cytotoxic and neurotoxic assays were performed for peptidomimetic 6b using HEK 293T cells and cortex neurons from 19 day old Wistar-Kyoto rat embryos, respectively, suggesting this analogue displays no toxicity effect in these assays up to 100 μM. Conformational energy minimization for 6b shows that this peptidomimetic cannot adopt the postulated type-II β-turn bioactive conformation, endorsing the possibility of an extended bioactive conformation as claimed by other researchers as a second bioactive conformation of MIF-1. Overall, the pharmacological and toxicological profile of peptidomimetic 6b together with its favorable druglike properties and structural simplicity makes it a potential lead compound for further development and optimization.
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Affiliation(s)
- Ivo E. Sampaio-Dias
- LAQV/REQUIMTE, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal
| | - Sara C. Silva-Reis
- LAQV/REQUIMTE, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal
| | - Xerardo García-Mera
- Department of Organic Chemistry, Faculty of Pharmacy, University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - José Brea
- Innopharma Screening Platform, Biofarma Research Group, Centre of Research in Molecular Medicine and Chronic Diseases (CIMUS), University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - M. Isabel Loza
- Innopharma Screening Platform, Biofarma Research Group, Centre of Research in Molecular Medicine and Chronic Diseases (CIMUS), University of Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - Carla S. Alves
- CQM - Centro de Química da Madeira, Universidade da Madeira, Campus Universitário
da Penteada, 9020-105 Funchal, Portugal
| | - Manuel Algarra
- CQM - Centro de Química da Madeira, Universidade da Madeira, Campus Universitário
da Penteada, 9020-105 Funchal, Portugal
| | - José E. Rodríguez-Borges
- LAQV/REQUIMTE, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal
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Qiu J, Zhao L, Xu S, Chen Q, Chen L, Liu B, Hong Q, Lu Z, He J. Identification and Characterization of a Novel pic Gene Cluster Responsible for Picolinic Acid Degradation in Alcaligenes faecalis JQ135. J Bacteriol 2019; 201:e00077-19. [PMID: 31160400 DOI: 10.1128/JB.00077-19] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 05/30/2019] [Indexed: 11/20/2022] Open
Abstract
Picolinic acid (PA) is a natural toxic pyridine derivative. Microorganisms can degrade and utilize PA for growth. However, the full catabolic pathway of PA and its physiological and genetic foundation remain unknown. In this study, we identified a gene cluster, designated picRCEDFB4B3B2B1A1A2A3, responsible for the degradation of PA from Alcaligenes faecalis JQ135. Our results suggest that PA degradation pathway occurs as follows: PA was initially 6-hydroxylated to 6-hydroxypicolinic acid (6HPA) by PicA (a PA dehydrogenase). 6HPA was then 3-hydroxylated by PicB, a four-component 6HPA monooxygenase, to form 3,6-dihydroxypicolinic acid (3,6DHPA), which was then converted into 2,5-dihydroxypyridine (2,5DHP) by the decarboxylase PicC. 2,5DHP was further degraded to fumaric acid through PicD (2,5DHP 5,6-dioxygenase), PicE (N-formylmaleamic acid deformylase), PicF (maleamic acid amidohydrolase), and PicG (maleic acid isomerase). Homologous pic gene clusters with diverse organizations were found to be widely distributed in Alpha-, Beta-, and Gammaproteobacteria Our findings provide new insights into the microbial catabolism of environmental toxic pyridine derivatives.IMPORTANCE Picolinic acid is a common metabolite of l-tryptophan and some aromatic compounds and is an important intermediate in organic chemical synthesis. Although the microbial degradation/detoxification of picolinic acid has been studied for over 50 years, the underlying molecular mechanisms are still unknown. Here, we show that the pic gene cluster is responsible for the complete degradation of picolinic acid. The pic gene cluster was found to be widespread in other Alpha-, Beta-, and Gammaproteobacteria These findings provide a new perspective for understanding the catabolic mechanisms of picolinic acid in bacteria.
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Qiu J, Zhang Y, Yao S, Ren H, Qian M, Hong Q, Lu Z, He J. Novel 3,6-Dihydroxy picolinic Acid Decarboxylase-Mediated Picolinic Acid Catabolism in Alcaligenes faecalis JQ135. J Bacteriol 2019; 201:e00665-18. [PMID: 30692170 DOI: 10.1128/JB.00665-18] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Accepted: 01/18/2019] [Indexed: 11/20/2022] Open
Abstract
Picolinic acid (PA), a typical C-2-carboxylated pyridine derivative, is a metabolite of l-tryptophan and many other aromatic compounds in mammalian and microbial cells. Microorganisms can degrade and utilize PA for growth. However, the precise mechanism of PA metabolism remains unknown. Alcaligenes faecalis strain JQ135 utilizes PA as its carbon and nitrogen source for growth. In this study, we screened a 6-hydroxypicolinic acid (6HPA) degradation-deficient mutant through random transposon mutagenesis. The mutant hydroxylated 6HPA into an intermediate, identified as 3,6-dihydroxypicolinic acid (3,6DHPA), with no further degradation. A novel decarboxylase, PicC, was identified to be responsible for the decarboxylation of 3,6DHPA to 2,5-dihydroxypyridine. Although, PicC belonged to the amidohydrolase 2 family, it shows low similarity (<45%) compared to other reported amidohydrolase 2 family decarboxylases. Moreover, PicC was found to form a monophyletic group in the phylogenetic tree constructed using PicC and related proteins. Further, the genetic deletion and complementation results demonstrated that picC was essential for PA degradation. The PicC was Zn2+-dependent nonoxidative decarboxylase that can specifically catalyze the irreversible decarboxylation of 3,6DHPA to 2,5-dihydroxypyridine. The Km and k cat toward 3,6DHPA were observed to be 13.44 μM and 4.77 s-1, respectively. Site-directed mutagenesis showed that His163 and His216 were essential for PicC activity. This study provides new insights into the microbial metabolism of PA at molecular level.IMPORTANCE Picolinic acid is a natural toxic pyridine derived from l-tryptophan metabolism and other aromatic compounds in mammalian and microbial cells. Microorganisms can degrade and utilize picolinic acid for their growth, and thus a microbial degradation pathway of picolinic acid has been proposed. Picolinic acid is converted into 6-hydroxypicolinic acid, 3,6-dihydroxypicolinic acid, and 2,5-dihydroxypyridine in turn. However, there was no physiological and genetic validation for this pathway. This study demonstrated that 3,6-dihydroxypicolinic acid was an intermediate in picolinic acid catabolism and further identified and characterized a novel amidohydrolase 2 family decarboxylase PicC. PicC was also shown to catalyze the decarboxylation of 3,6-dihydroxypicolinic acid into 2,5-dihydroxypyridine. This study provides a basis for understanding picolinic acid degradation and its underlying molecular mechanism.
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Myint AM, Kim YK. Network beyond IDO in psychiatric disorders: revisiting neurodegeneration hypothesis. Prog Neuropsychopharmacol Biol Psychiatry 2014; 48:304-13. [PMID: 24184687 DOI: 10.1016/j.pnpbp.2013.08.008] [Citation(s) in RCA: 158] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2012] [Revised: 08/08/2013] [Accepted: 08/17/2013] [Indexed: 12/16/2022]
Abstract
The involvement of immune system activation in the pathophysiology of certain psychiatric disorders is well documented. Inflammatory molecules such as pro-inflammatory cytokines could enhance the activity of the indoleamine 2,3-dioxygenase (IDO) enzyme which is the first rate-limiting enzyme of the tryptophan degradation pathway, the kynurenine pathway. The increased tryptophan degradation could induce serotonin depletion and depressive mood. On the other hand, the downstream metabolites from this pathway, such as 3-hydroxykynurenine, quinolinic acid and kynurenic acid, are neuroactive metabolites which can modulate several neurotransmissions, such as glutamatergic, GABAergic, dopaminergic and noradrenergic neurotransmissions, which in turn induce changes in neuronal-glial network and neuropsychiatric consequences. In this issue, we have revised the previous 'neurodegeneration hypothesis,' which explained the involvement of cytokines and IDO pathway interaction in depression, with a further extended view related to the network beyond IDO, the network between immune molecules, tryptophan metabolites and different neurotransmitters, in depression and other major psychiatric disorders such as schizophrenia, bipolar disorder and childhood psychiatric disorders.
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Affiliation(s)
- Aye-Mu Myint
- Psychiatric Hospital, Ludwig Maximilian University, Nussbaumstrasse 7; D-80336 Munich, Germany; School for Mental Health and Neuroscience, Maastricht University, The Netherlands.
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Wang X, Davis I, Liu A, Shamsi SA. Development of a CZE-ESI-MS assay with a sulfonated capillary for profiling picolinic acid and quinolinic acid formation in multienzyme system. Electrophoresis 2013; 34:1828-35. [PMID: 23576119 PMCID: PMC4153595 DOI: 10.1002/elps.201200679] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 01/26/2013] [Accepted: 01/27/2013] [Indexed: 11/08/2022]
Abstract
This article describes the development of a reliable CZE-ESI-MS method to simultaneously separate and quantitate three specific metabolites (3-hydroxyanthranilic acid (3-HAA), quinolinic acid (QA), and picolinic acid (PA)) of the kynurenine pathway (KP) of tryptophan catabolism. Using a covalently bonded sulfonated capillary, the parameters such as pH, type of background electrolyte, type of organic solvent, nebulizer pressure as well as both negative and positive ESI-MS modes were optimized to achieve the best Rs and S/N of three KP metabolites. The developed CZE-ESI-MS assay provided high resolution of PA/QA, high specificity, a total analysis time of 10 min with satisfactory intraday and interday repeatability of migration time and peak areas. Under optimized CZE-ESI-MS conditions, the calibration curves over a concentration range of 19-300 μM for 3-HAA and QA, and 75-300 μM for PA were simultaneously generated. The method was successfully applied for the first time to profile the concentrations of initial substrate, 3-HAA, and its eventual products, PA and QA, formed in the complex multienzyme system. As the ratio of two enzymes, 3-hydroxyanthranilate 3,4-dioxygenase (HAO) and α-amino-β-carboxymuconate-ε-semialdehyde decarboxylase (ACMSD) decreases, the concentration of QA approaches essentially zero indicating that all ACMS formed by the action of HAO is consumed by ACMSD rather than its spontaneous decay to QA.
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Affiliation(s)
- Xiaochun Wang
- Department of Chemistry, Center of Diagnostics and Therapeutics, Georgia State University, 50 Decatur Street, Atlanta, GA 30303, USA
| | - Ian Davis
- Department of Chemistry, Center of Diagnostics and Therapeutics, Georgia State University, 50 Decatur Street, Atlanta, GA 30303, USA
| | - Aimin Liu
- Department of Chemistry, Center of Diagnostics and Therapeutics, Georgia State University, 50 Decatur Street, Atlanta, GA 30303, USA
| | - Shahab A. Shamsi
- Department of Chemistry, Center of Diagnostics and Therapeutics, Georgia State University, 50 Decatur Street, Atlanta, GA 30303, USA
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