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Verma S, Ambatwar R, Datusalia AK, Khatik GL. Convenient One-Pot Synthesis of Kynurenic Acid Ethyl Ester and Exploration to Direct Synthesis of Neuroprotective Kynurenic Acid and Amide Derivatives. J Org Chem 2023; 88:10494-10500. [PMID: 37463064 DOI: 10.1021/acs.joc.3c00446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
Kynurenic acid (KYNA) is an endogenous molecule, which is a non-selective antagonist of ionotropic glutamate receptors and has been found to have neuroprotective activity. A supplement of KYNA may be applicable for the treatment of neurodegenerative disease, but it does not cross the blood-brain barrier due to its polar nature. Therefore, its different esters and amide derivatives were explored as a prodrug, which can cross blood-brain barrier and transform into KYNA in situ. However, many esters and amide derivatives of KYNA are synthesized via coupling reaction or multi-step synthesis using different organic or metallic catalysts. Herein, we developed a novel one-pot, catalyst-free, convenient synthesis of KYNA ethyl esters using aniline and diethyl acetylene dicarboxylate in DMF under heating. We also explored the synthesis of KYNA and KYNA amide derivative in a simple manner with overall good yields via hydrolysis and condensation, respectively.
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Affiliation(s)
- Swati Verma
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research-Raebareli NIPER, Raebareli, Uttar Pradesh 226002, India
| | - Ramesh Ambatwar
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research-Raebareli NIPER, Raebareli, Uttar Pradesh 226002, India
| | - Ashok Kumar Datusalia
- Department of Pharmacology & Toxicology, National Institute of Pharmaceutical Education and Research-Raebareli NIPER, Raebareli, Uttar Pradesh 226002, India
| | - Gopal L Khatik
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research-Raebareli NIPER, Raebareli, Uttar Pradesh 226002, India
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Hornok V, Amin KWK, Kovács AN, Juhász Á, Katona G, Balogh GT, Csapó E. Increased blood-brain barrier permeability of neuroprotective drug by colloidal serum albumin carriers. Colloids Surf B Biointerfaces 2022; 220:112935. [DOI: 10.1016/j.colsurfb.2022.112935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 09/02/2022] [Accepted: 10/13/2022] [Indexed: 11/27/2022]
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Majerova P, Olesova D, Golisova G, Buralova M, Michalicova A, Vegh J, Piestansky J, Bhide M, Hanes J, Kovac A. Analog of kynurenic acid decreases tau pathology by modulating astrogliosis in rat model for tauopathy. Biomed Pharmacother 2022; 152:113257. [PMID: 35714514 DOI: 10.1016/j.biopha.2022.113257] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 05/30/2022] [Accepted: 06/06/2022] [Indexed: 11/17/2022] Open
Abstract
Kynurenines have immunomodulatory and neuroactive properties and can influence the central nervous system. Previous studies showed the involvement of the kynurenines in the pathogenesis and progression of neurodegenerative disease. In neurodegenerative disorders, including tauopathies, the tryptophan metabolism is shifted toward neurotoxic agents and the reduction of neuroprotectant products. Astrocyte-derived kynurenic acid serves as a neuroprotectant. However, systemic administration of kynurenic acid is not effective because of low permeability across the blood-brain barrier (BBB). We used a kynurenic acid analog with similar biological activity but higher brain permeability to overcome BBB limitations. In the present study, we used amide derivate of kynurenic acid N-(2-N, N-dimethylaminoethyl)- 4-oxo-1 H-quinoline-2-carboxamid (KYNA-1). We administered KYNA-1 for three months to tau transgenic rats SHR-24 and analyzed the effect on tau pathology and activation of glial cells. Primary glial cell cultures were applied to identify the mechanism of the KYNA-1 effect. KYNA-1 was not toxic to rats after chronic three-month administration. When chronically administered, KYNA-1 reduced hyperphosphorylation of insoluble tau in the brain of transgenic rats. Noteworthily, the plasma total tau was also reduced. We determined that the effect of KYNA-1 on tau pathology was induced through the modulation of glial activation. KYNA-1 inhibited LPS induced activation of astrocytes and induced transformation of microglia to M2 phenotype. We identified that the administration of KYNA-1 reduced tau hyperphosphorylation and neuroinflammation. KYNA-1 may serve as a promising treatment for tauopathies.
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Affiliation(s)
- Petra Majerova
- Institute of Neuroimmunology, Slovak Academy of Sciences, Dubravska cesta 9, 845 10 Bratislava, Slovakia.
| | - Dominika Olesova
- Institute of Neuroimmunology, Slovak Academy of Sciences, Dubravska cesta 9, 845 10 Bratislava, Slovakia; Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy in Kosice, Kosice, Slovakia.
| | - Greta Golisova
- Faculty of Natural Sciences, Department of Biochemistry, Comenius University in Bratislava, Mlynska dolina, Ilkovicova 6, 842 15 Bratislava, Slovakia.
| | - Martina Buralova
- Institute of Neuroimmunology, Slovak Academy of Sciences, Dubravska cesta 9, 845 10 Bratislava, Slovakia.
| | - Alena Michalicova
- Institute of Neuroimmunology, Slovak Academy of Sciences, Dubravska cesta 9, 845 10 Bratislava, Slovakia.
| | - Jozef Vegh
- Institute of Neuroimmunology, Slovak Academy of Sciences, Dubravska cesta 9, 845 10 Bratislava, Slovakia.
| | - Juraj Piestansky
- Department of Pharmaceutical Analysis and Nuclear Pharmacy, Faculty of Pharmacy, Comenius University in Bratislava, Odbojarov 10, SK-832 32 Bratislava, Slovakia.
| | - Mangesh Bhide
- Laboratory of Biomedical Microbiology and Immunology, The University of Veterinary Medicine and Pharmacy in Kosice, Kosice, Slovakia.
| | - Jozef Hanes
- Institute of Neuroimmunology, Slovak Academy of Sciences, Dubravska cesta 9, 845 10 Bratislava, Slovakia.
| | - Andrej Kovac
- Institute of Neuroimmunology, Slovak Academy of Sciences, Dubravska cesta 9, 845 10 Bratislava, Slovakia.
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Tanaka M, Spekker E, Szabó Á, Polyák H, Vécsei L. Modelling the neurodevelopmental pathogenesis in neuropsychiatric disorders. Bioactive kynurenines and their analogues as neuroprotective agents-in celebration of 80th birthday of Professor Peter Riederer. J Neural Transm (Vienna) 2022; 129:627-642. [PMID: 35624406 DOI: 10.1007/s00702-022-02513-5] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Accepted: 05/05/2022] [Indexed: 02/06/2023]
Abstract
Following introduction of the monoamine oxidase type B inhibitor selegiline for the treatment of Parkinson's disease (PD), discovery of the action mechanism of Alzheimer's disease-modifying agent memantine, the role of iron in PD, and the loss of electron transport chain complex I in PD, and development of the concept of clinical neuroprotection, Peter Riederer launched one of the most challenging research project neurodevelopmental aspects of neuropsychiatric disorders. The neurodevelopmental theory holds that a disruption of normal brain development in utero or during early life underlies the subsequent emergence of neuropsychiatric symptoms during later life. Indeed, the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition and the International Classification of Diseases, 11th Revision categorize autism spectrum disorder and attention deficit hyperactivity disorder in neurodevelopmental disorders (NDDs). More and more evidence, especially from preclinical studies, is revealing that neurodevelopmental pathology is not limited to the diagnostic class above, but also contributes to the development of other psychiatric disorders such as schizophrenia, bipolar disorder, and obsessive-compulsive disorder as well as neurodegenerative diseases such as PD and Huntington's disease. Preclinical animal research is taking a lead in understanding the pathomechanisms of NDDs, searching for novel targets, and developing new neuroprotective agents against NDDs. This narrative review discusses emerging evidence of the neurodevelopmental etiology of neuropsychiatric disorders, recent advances in modelling neurodevelopmental pathogenesis, potential strategies of clinical neuroprotection using novel kynurenine metabolites and analogues, and future research direction for NDDs.
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Affiliation(s)
- Masaru Tanaka
- MTA-SZTE Neuroscience Research Group, Hungarian Academy of Sciences, University of Szeged (MTA-SZTE), Semmelweis u. 6, 6725, Szeged, Hungary
| | - Eleonóra Spekker
- MTA-SZTE Neuroscience Research Group, Hungarian Academy of Sciences, University of Szeged (MTA-SZTE), Semmelweis u. 6, 6725, Szeged, Hungary
| | - Ágnes Szabó
- Department of Neurology, Albert Szent-György Medical School, University of Szeged, Semmelweis u. 6, 6725, Szeged, Hungary
| | - Helga Polyák
- Department of Neurology, Albert Szent-György Medical School, University of Szeged, Semmelweis u. 6, 6725, Szeged, Hungary
| | - László Vécsei
- MTA-SZTE Neuroscience Research Group, Hungarian Academy of Sciences, University of Szeged (MTA-SZTE), Semmelweis u. 6, 6725, Szeged, Hungary. .,Department of Neurology, Albert Szent-György Medical School, University of Szeged, Semmelweis u. 6, 6725, Szeged, Hungary.
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Martos D, Tuka B, Tanaka M, Vécsei L, Telegdy G. Memory Enhancement with Kynurenic Acid and Its Mechanisms in Neurotransmission. Biomedicines 2022; 10:biomedicines10040849. [PMID: 35453599 PMCID: PMC9027307 DOI: 10.3390/biomedicines10040849] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Revised: 03/28/2022] [Accepted: 04/02/2022] [Indexed: 02/04/2023] Open
Abstract
Kynurenic acid (KYNA) is an endogenous tryptophan (Trp) metabolite known to possess neuroprotective property. KYNA plays critical roles in nociception, neurodegeneration, and neuroinflammation. A lower level of KYNA is observed in patients with neurodegenerative diseases such as Alzheimer’s and Parkinson’s diseases or psychiatric disorders such as depression and autism spectrum disorders, whereas a higher level of KYNA is associated with the pathogenesis of schizophrenia. Little is known about the optimal concentration for neuroprotection and the threshold for neurotoxicity. In this study the effects of KYNA on memory functions were investigated by passive avoidance test in mice. Six different doses of KYNA were administered intracerebroventricularly to previously trained CFLP mice and they were observed for 24 h. High doses of KYNA (i.e., 20–40 μg/2 μL) significantly decreased the avoidance latency, whereas a low dose of KYNA (0.5 μg/2 μL) significantly elevated it compared with controls, suggesting that the low dose of KYNA enhanced memory function. Furthermore, six different receptor blockers were applied to reveal the mechanisms underlying the memory enhancement induced by KYNA. The series of tests revealed the possible involvement of the serotonergic, dopaminergic, α and β adrenergic, and opiate systems in the nootropic effect. This study confirmed that a low dose of KYNA improved a memory component of cognitive domain, which was mediated by, at least in part, four systems of neurotransmission in an animal model of learning and memory.
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Affiliation(s)
- Diána Martos
- MTA-SZTE Neuroscience Research Group, Hungarian Academy of Sciences, University of Szeged (MTA-SZTE), Semmelweis u. 6, H-6725 Szeged, Hungary; (D.M.); (B.T.); (M.T.)
| | - Bernadett Tuka
- MTA-SZTE Neuroscience Research Group, Hungarian Academy of Sciences, University of Szeged (MTA-SZTE), Semmelweis u. 6, H-6725 Szeged, Hungary; (D.M.); (B.T.); (M.T.)
| | - Masaru Tanaka
- MTA-SZTE Neuroscience Research Group, Hungarian Academy of Sciences, University of Szeged (MTA-SZTE), Semmelweis u. 6, H-6725 Szeged, Hungary; (D.M.); (B.T.); (M.T.)
| | - László Vécsei
- MTA-SZTE Neuroscience Research Group, Hungarian Academy of Sciences, University of Szeged (MTA-SZTE), Semmelweis u. 6, H-6725 Szeged, Hungary; (D.M.); (B.T.); (M.T.)
- Department of Neurology, Albert Szent-Györgyi Medical School, University of Szeged, Semmelweis u. 6, H-6725 Szeged, Hungary
- Correspondence: ; Tel.: +36-62-342-361
| | - Gyula Telegdy
- Department of Pathophysiology, Albert Szent-Györgyi Medical School, University of Szeged, Semmelweis u. 5, H-6725 Szeged, Hungary;
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Lo YC, Lin CL, Fang WY, Lőrinczi B, Szatmári I, Chang WH, Fülöp F, Wu SN. Effective Activation by Kynurenic Acid and Its Aminoalkylated Derivatives on M-Type K + Current. Int J Mol Sci 2021; 22:ijms22031300. [PMID: 33525680 PMCID: PMC7865226 DOI: 10.3390/ijms22031300] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/25/2021] [Accepted: 01/26/2021] [Indexed: 12/24/2022] Open
Abstract
Kynurenic acid (KYNA, 4-oxoquinoline-2-carboxylic acid), an intermediate of the tryptophan metabolism, has been recognized to exert different neuroactive actions; however, the need of how it or its aminoalkylated amide derivative N-(2-(dimethylamino)ethyl)-3-(morpholinomethyl)-4-oxo-1,4-dihydroquinoline-2-carboxamide (KYNA-A4) exerts any effects on ion currents in excitable cells remains largely unmet. In this study, the investigations of how KYNA and other structurally similar KYNA derivatives have any adjustments on different ionic currents in pituitary GH3 cells and hippocampal mHippoE-14 neurons were performed by patch-clamp technique. KYNA or KYNA-A4 increased the amplitude of M-type K+ current (IK(M)) and concomitantly enhanced the activation time course of the current. The EC50 value required for KYNA- or KYNA-A4 -stimulated IK(M) was yielded to be 18.1 or 6.4 μM, respectively. The presence of KYNA or KYNA-A4 shifted the relationship of normalized IK(M)-conductance versus membrane potential to more depolarized potential with no change in the gating charge of the current. The voltage-dependent hysteretic area of IK(M) elicited by long-lasting triangular ramp pulse was observed in GH3 cells and that was increased during exposure to KYNA or KYNA-A4. In cell-attached current recordings, addition of KYNA raised the open probability of M-type K+ channels, along with increased mean open time of the channel. Cell exposure to KYNA or KYNA-A4 mildly inhibited delayed-rectifying K+ current; however, neither erg-mediated K+ current, hyperpolarization-activated cation current, nor voltage-gated Na+ current in GH3 cells was changed by KYNA or KYNA-A4. Under whole-cell, current-clamp recordings, exposure to KYNA or KYNA-A4 diminished the frequency of spontaneous action potentials; moreover, their reduction in firing frequency was attenuated by linopirdine, yet not by iberiotoxin or apamin. In hippocampal mHippoE-14 neurons, the addition of KYNA also increased the IK(M) amplitude effectively. Taken together, the actions presented herein would be one of the noticeable mechanisms through which they modulate functional activities of excitable cells occurring in vivo.
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Affiliation(s)
- Yi-Ching Lo
- Department of Pharmacology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (W.-Y.F.); (W.-H.C.)
- Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Correspondence: (Y.-C.L.); (S.-N.W.); Tel.: +886-7-3234686 (Y.-C.L.); +886-6-2353535-5334 (S.-N.W.); Fax: +886-7-3234686 (Y.-C.L.); +886-6-2362780 (S.-N.W.)
| | - Chih-Lung Lin
- Department of Neurosurgery, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan;
- Department of Neurosurgery, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Wei-Yu Fang
- Department of Pharmacology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (W.-Y.F.); (W.-H.C.)
| | - Bálint Lőrinczi
- Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary; (B.L.); (I.S.); (F.F.)
| | - István Szatmári
- Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary; (B.L.); (I.S.); (F.F.)
| | - Wan-Hsuan Chang
- Department of Pharmacology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (W.-Y.F.); (W.-H.C.)
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Ferenc Fülöp
- Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary; (B.L.); (I.S.); (F.F.)
- MTA-SZTE Stereochemistry Research Group, Hungarian Academy of Sciences, Eötvös u. 6, H-6720 Szeged, Hungary
| | - Sheng-Nan Wu
- Institute of Basic Medical Sciences, National Cheng Kung University Medical College, Tainan City 70101, Taiwan
- Department of Physiology, National Cheng Kung University Medical College, Tainan City 70101, Taiwan
- Correspondence: (Y.-C.L.); (S.-N.W.); Tel.: +886-7-3234686 (Y.-C.L.); +886-6-2353535-5334 (S.-N.W.); Fax: +886-7-3234686 (Y.-C.L.); +886-6-2362780 (S.-N.W.)
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Fehér E, Szatmári I, Dudás T, Zalatnai A, Farkas T, Lőrinczi B, Fülöp F, Vécsei L, Toldi J. Structural Evaluation and Electrophysiological Effects of Some Kynurenic Acid Analogs. Molecules 2019; 24:molecules24193502. [PMID: 31561643 PMCID: PMC6803921 DOI: 10.3390/molecules24193502] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 09/23/2019] [Accepted: 09/24/2019] [Indexed: 01/28/2023] Open
Abstract
Kynurenic acid (KYNA), a metabolite of tryptophan, as an excitatory amino acid receptor antagonist is an effective neuroprotective agent in case of excitotoxicity, which is the hallmark of brain ischemia and several neurodegenerative processes. Therefore, kynurenine pathway, KYNA itself, and its derivatives came into the focus of research. During the past fifteen years, our research group has developed several neuroactive KYNA derivatives, some of which proved to be neuroprotective in preclinical studies. In this study, the synthesis of these KYNA derivatives and their evaluation with divergent molecular characteristics are presented together with their most typical effects on the monosynaptic transmission in CA1 region of the hippocampus of the rat. Their effects on the basic neuronal activity (on the field excitatory postsynaptic potentials: fEPSP) were studied in in vitro hippocampal slices in 1 and 200 μM concentrations. KYNA and its derivative 4 in both 1 and 200 μM concentrations proved to be inhibitory, while derivative 8 only in 200 μM decreased the amplitudes of fEPSPs. Derivative 5 facilitated the fEPSPs in 200 μM concentration. This is the first comparative study which evaluates the structural and functional differences of formerly and newly developed KYNA analogs. Considerations on possible relations between molecular structures and their physiological effects are presented.
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Affiliation(s)
- Evelin Fehér
- Department of Neurology, Interdisciplinary Excellence Centre, Albert Szent-Györgyi Clinical Center, Faculty of Medicine, University of Szeged, Semmelweis u. 6, H-6725 Szeged, Hungary.
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary.
| | - István Szatmári
- Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary.
- Stereochemistry Research Group of the Hungarian Academy of Sciences, Eötvös utca 6, H-6720 Szeged, Hungary.
- Institute of Pharmaceutical Chemistry, Interdisciplinary Excellence Centre, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary.
| | - Tamás Dudás
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary.
| | - Anna Zalatnai
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary.
| | - Tamás Farkas
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary.
| | - Bálint Lőrinczi
- Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary.
- Stereochemistry Research Group of the Hungarian Academy of Sciences, Eötvös utca 6, H-6720 Szeged, Hungary.
| | - Ferenc Fülöp
- Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary.
- Stereochemistry Research Group of the Hungarian Academy of Sciences, Eötvös utca 6, H-6720 Szeged, Hungary.
- Institute of Pharmaceutical Chemistry, Interdisciplinary Excellence Centre, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary.
| | - László Vécsei
- Department of Neurology, Interdisciplinary Excellence Centre, Albert Szent-Györgyi Clinical Center, Faculty of Medicine, University of Szeged, Semmelweis u. 6, H-6725 Szeged, Hungary.
- MTA-SZTE Neuroscience Research Group, Semmelweis u. 6, H-6725 Szeged, Hungary.
| | - József Toldi
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép fasor 52, H-6726 Szeged, Hungary.
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Zádori D, Veres G, Szalárdy L, Klivényi P, Vécsei L. Alzheimer's Disease: Recent Concepts on the Relation of Mitochondrial Disturbances, Excitotoxicity, Neuroinflammation, and Kynurenines. J Alzheimers Dis 2019; 62:523-547. [PMID: 29480191 DOI: 10.3233/jad-170929] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The pathomechanism of Alzheimer's disease (AD) certainly involves mitochondrial disturbances, glutamate excitotoxicity, and neuroinflammation. The three main aspects of mitochondrial dysfunction in AD, i.e., the defects in dynamics, altered bioenergetics, and the deficient transport, act synergistically. In addition, glutamatergic neurotransmission is affected in several ways. The balance between synaptic and extrasynaptic glutamatergic transmission is shifted toward the extrasynaptic site contributing to glutamate excitotoxicity, a phenomenon augmented by increased glutamate release and decreased glutamate uptake. Neuroinflammation in AD is predominantly linked to central players of the innate immune system, with central nervous system (CNS)-resident microglia, astroglia, and perivascular macrophages having been implicated at the cellular level. Several abnormalities have been described regarding the activation of certain steps of the kynurenine (KYN) pathway of tryptophan metabolism in AD. First of all, the activation of indolamine 2,3-dioxygenase, the first and rate-limiting step of the pathway, is well-demonstrated. 3-Hydroxy-L-KYN and its metabolite, 3-hydroxy-anthranilic acid have pro-oxidant, antioxidant, and potent immunomodulatory features, giving relevance to their alterations in AD. Another metabolite, quinolinic acid, has been demonstrated to be neurotoxic, promoting glutamate excitotoxicity, reactive oxygen species production, lipid peroxidation, and microglial neuroinflammation, and its abundant presence in AD pathologies has been demonstrated. Finally, the neuroprotective metabolite, kynurenic acid, has been associated with antagonistic effects at glutamate receptors, free radical scavenging, and immunomodulation, giving rise to potential therapeutic implications. This review presents the multiple connections of KYN pathway-related alterations to three main domains of AD pathomechanism, such as mitochondrial dysfunction, excitotoxicity, and neuroinflammation, implicating possible therapeutic options.
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Affiliation(s)
- Dénes Zádori
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary
| | - Gábor Veres
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary
| | - Levente Szalárdy
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary
| | - Péter Klivényi
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary
| | - László Vécsei
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Szeged, Hungary.,MTA-SZTE Neuroscience Research Group, Szeged, Hungary
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Lajkó E, Tuka B, Fülöp F, Krizbai I, Toldi J, Magyar K, Vécsei L, Kőhidai L. Kynurenic acid and its derivatives are able to modulate the adhesion and locomotion of brain endothelial cells. J Neural Transm (Vienna) 2018; 125:899-912. [PMID: 29332257 DOI: 10.1007/s00702-018-1839-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 01/03/2018] [Indexed: 01/26/2023]
Abstract
The neuroprotective actions of kynurenic acid (KYNA) and its derivatives in several neurodegenerative disorders [characterized by damage to the cerebral endothelium and to the blood-brain barrier (BBB)] are well established. Cell-extracellular matrix (ECM) adhesion is supposedly involved in recovery of impaired cerebral endothelium integrity (endothelial repair). The present work aimed to investigate the effects of KYNA and its synthetic derivatives on cellular behaviour (e.g. adhesion and locomotion) and on morphology of the GP8 rat brain endothelial cell line, modeling the BBB endothelium. The effects of KYNA and its derivatives on cell adhesion were measured using an impedance-based technique, the xCELLigence SP system. Holographic microscopy (Holomonitor™ M4) was used to analyse both chemokinetic responses and morphometry. The GP8 cells proved to be a suitable model cell line for investigating cell adhesion and the locomotion modulator effects of kynurenines. KYNA enhanced cell adhesion and spreading, and also decreased the migration/motility of GP8 cells at physiological concentrations (10-9 and 10-7 mol/L). The derivatives containing an amide side-chain at the C2 position (KYNA-A1 and A2) had lower adhesion inducer effects compared to KYNA. All synthetic analogues (except KYNA-A5) had a time-dependent inhibitory effect on GP8 cell adhesion at a supraphysiological concentration (10-3 mol/L). The immobilization promoting effect of KYNA and the adhesion inducer activity of its derivatives indicate that these compounds could contribute to maintaining or restoring the protective function of brain endothelium; they also suggest that cell-ECM adhesion and related cell responses (e.g. migration/motility) could be potential new targets of KYNA.
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Affiliation(s)
- Eszter Lajkó
- Department of Genetics, Cell- and Immunobiology, Semmelweis University, Nagyvárad tér 4, Budapest, 1089, Hungary
| | - Bernadett Tuka
- MTA-SZTE Neuroscience Research Group, Semmelweis u. 6, Szeged, 6725, Hungary
| | - Ferenc Fülöp
- Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, Szeged, 6720, Hungary
- Stereochemistry Research Group of the Hungarian Academy of Sciences, Eötvös utca 6, Szeged, H-6720, Hungary
| | - István Krizbai
- Institute of Biophysics, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62, Szeged, 6726, Hungary
| | - József Toldi
- MTA-SZTE Neuroscience Research Group, Semmelweis u. 6, Szeged, 6725, Hungary
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Közép Fasor 52, Szeged, 6726, Hungary
| | - Kálmán Magyar
- Department of Pharmacodynamics, Semmelweis University, Nagyvárad tér 4, Budapest, 1089, Hungary
| | - László Vécsei
- MTA-SZTE Neuroscience Research Group, Semmelweis u. 6, Szeged, 6725, Hungary
- Department of Neurology, University of Szeged, Semmelweis u. 6, Szeged, 6725, Hungary
| | - László Kőhidai
- Department of Genetics, Cell- and Immunobiology, Semmelweis University, Nagyvárad tér 4, Budapest, 1089, Hungary.
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10
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Samavati R, Zádor F, Szűcs E, Tuka B, Martos D, Veres G, Gáspár R, Mándity IM, Fülöp F, Vécsei L, Benyhe S, Borsodi A. Kynurenic acid and its analogue can alter the opioid receptor G-protein signaling after acute treatment via NMDA receptor in rat cortex and striatum. J Neurol Sci 2017; 376:63-70. [PMID: 28431630 DOI: 10.1016/j.jns.2017.02.053] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 02/21/2017] [Accepted: 02/23/2017] [Indexed: 01/15/2023]
Abstract
Previously, we have shown that the N-methyl d-aspartate (NMDA)-receptor antagonist kynurenic acid (KYNA) and its analogue KYNA1 do not bind directly to mu, kappa and delta opioid receptors in vitro. On the other hand, chronic administration of KYNA and KYNA1 resulted in region (cortex vs striatum) and opioid receptor-type specific alterations in G-protein activation of mouse brain homogenates. Here we describe for the first time the acute effect of KYNA and KYNA1 on opioid receptor function with the possible involvement of the NMDA receptor. The acute 30minute in vivo KYNA1 and KYNA treatments altered opioid receptor G-protein signaling or ligand potency depending on the opioid receptor type and brain region (rat cortex vs striatum) using [35S]GTPγS binding assays. Pretreatment with the NMDA receptor antagonist MK-801 impaired or reversed the effects of KYNA1 and KYNA. These results suggest an NMDA receptor mediated effect. After acute 30minute treatment HPLC measurements revealed a similar KYNA1 and a higher KYNA plasma concentration compared to cerebrospinal fluid concentrations. Finally, KYNA, KYNA1 and MK-801 showed comparable results in opioid receptor G-protein activity and ligand potency with acute in vivo treatments when they were administered in vitro for 30min on isolated cortex and striatum slices. We previously demonstrated that KYNA1 and KYNA acutely altered opioid receptor function in vivo and in vitro through the NMDA receptor depending on the opioid receptor type and brain region. This study may lead to a new, indirect approach to influence opioid receptor signaling.
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Affiliation(s)
- Reza Samavati
- Institute of Biochemistry, Biological Research Center, Hungarian Academy of Sciences, Temesvári krt. 62, H-6726 Szeged, Hungary; Institute of Pharmacodynamics and Biopharmacy, Faculty of Pharmacy, University of Szeged, Eötvös u. 6, 6720 Szeged, Hungary
| | - Ferenc Zádor
- Institute of Biochemistry, Biological Research Center, Hungarian Academy of Sciences, Temesvári krt. 62, H-6726 Szeged, Hungary.
| | - Edina Szűcs
- Institute of Biochemistry, Biological Research Center, Hungarian Academy of Sciences, Temesvári krt. 62, H-6726 Szeged, Hungary
| | - Bernadett Tuka
- Department of Neurology, Faculty of Medicine, University of Szeged, Semmelweis utca 6, H-6725 Szeged, Hungary; MTA-SZTE Neuroscience Research Group, University of Szeged, Semmelweis utca 6, H-6725 Szeged, Hungary
| | - Diána Martos
- Department of Neurology, Faculty of Medicine, University of Szeged, Semmelweis utca 6, H-6725 Szeged, Hungary
| | - Gábor Veres
- Department of Neurology, Faculty of Medicine, University of Szeged, Semmelweis utca 6, H-6725 Szeged, Hungary; MTA-SZTE Neuroscience Research Group, University of Szeged, Semmelweis utca 6, H-6725 Szeged, Hungary
| | - Róbert Gáspár
- Institute of Pharmacodynamics and Biopharmacy, Faculty of Pharmacy, University of Szeged, Eötvös u. 6, 6720 Szeged, Hungary
| | - István M Mándity
- Institute of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Szeged, Eötvös u. 6, 6720 Szeged, Hungary
| | - Ferenc Fülöp
- Institute of Pharmaceutical Chemistry, Faculty of Pharmacy, University of Szeged, Eötvös u. 6, 6720 Szeged, Hungary
| | - László Vécsei
- Department of Neurology, Faculty of Medicine, University of Szeged, Semmelweis utca 6, H-6725 Szeged, Hungary; MTA-SZTE Neuroscience Research Group, University of Szeged, Semmelweis utca 6, H-6725 Szeged, Hungary
| | - Sándor Benyhe
- Institute of Biochemistry, Biological Research Center, Hungarian Academy of Sciences, Temesvári krt. 62, H-6726 Szeged, Hungary
| | - Anna Borsodi
- Institute of Biochemistry, Biological Research Center, Hungarian Academy of Sciences, Temesvári krt. 62, H-6726 Szeged, Hungary; Bio-Targeting Ltd., Vitez u. 1, 6722 Szeged, Hungary
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11
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A four-component Pfitzinger reaction: synthesis of 2-pyronylquinolin-4-carbamides. RESEARCH ON CHEMICAL INTERMEDIATES 2017. [DOI: 10.1007/s11164-017-2885-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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12
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Majláth Z, Török N, Toldi J, Vécsei L. Memantine and Kynurenic Acid: Current Neuropharmacological Aspects. Curr Neuropharmacol 2016; 14:200-9. [PMID: 26564141 PMCID: PMC4825950 DOI: 10.2174/1570159x14666151113123221] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 04/22/2015] [Accepted: 12/03/2015] [Indexed: 12/31/2022] Open
Abstract
Glutamatergic neurotransmission, of special importance in the human brain, is implicated in key brain functions such as synaptic plasticity and memory. The excessive activation of N-methyl- D-aspartate (NMDA) receptors may result in excitotoxic neuronal damage; this process has been implicated in the pathomechanism of different neurodegenerative disorders, such as Alzheimer’s disease (AD). Memantine is an uncompetitive antagonist of NMDA receptors with a favorable pharmacokinetic profile, and is therefore clinically well tolerated. Memantine is approved for the treatment of AD, but may additionally be beneficial for other dementia forms and pain conditions. Kynurenic acid
(KYNA) is an endogenous antagonist of NMDA receptors which has been demonstrated under experimental conditions to be neuroprotective. The development of a well-tolerated NMDA antagonist may offer a novel therapeutic option for the treatment of neurodegenerative disease and pain syndromes. KYNA may be a valuable candidate for future drug development.
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Affiliation(s)
| | | | | | - László Vécsei
- Department of Neurology, Faculty of Medicine, University of Szeged, Albert Szent-Györgyi Clinical Center, Semmelweis u. 6. H-6725 Szeged, Hungary.
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13
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Veres G, Fejes-Szabó A, Zádori D, Nagy-Grócz G, László AM, Bajtai A, Mándity I, Szentirmai M, Bohár Z, Laborc K, Szatmári I, Fülöp F, Vécsei L, Párdutz Á. A comparative assessment of two kynurenic acid analogs in the formalin model of trigeminal activation: a behavioral, immunohistochemical and pharmacokinetic study. J Neural Transm (Vienna) 2016; 124:99-112. [PMID: 27629500 DOI: 10.1007/s00702-016-1615-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 08/31/2016] [Indexed: 12/20/2022]
Abstract
Kynurenic acid (KYNA) has well-established protective properties against glutamatergic neurotransmission, which plays an essential role in the activation and sensitization process during some primary headache disorders. The goal of this study was to compare the effects of two KYNA analogs, N-(2-N,N-dimethylaminoethyl)-4-oxo-1H-quinoline-2-carboxamide hydrochloride (KA-1) and N-(2-N-pyrrolidinylethyl)-4-oxo-1H-quinoline-2-carboxamide hydrochloride (KA-2), in the orofacial formalin test of trigeminal pain. Following pretreatment with KA-1 or KA-2, rats were injected with subcutaneous formalin solution in the right whisker pad. Thereafter, the rubbing activity and c-Fos immunoreactivity changes in the spinal trigeminal nucleus pars caudalis (TNC) were investigated. To obtain pharmacokinetic data, KA-1, KA-2 and KYNA concentrations were measured following KA-1 or KA-2 injection. Behavioral tests demonstrated that KA-2 induced larger amelioration of formalin-evoked alterations as compared with KA-1 and the assessment of c-Fos immunoreactivity in the TNC yielded similar results. Although KA-1 treatment resulted in approximately four times larger area under the curve values in the serum relative to KA-2, the latter resulted in a higher KYNA elevation than in the case of KA-1. With regard to TNC, the concentration of KA-1 was under the limit of detection, while that of KA-2 was quite small and there was no major difference in the approximately tenfold KYNA elevations. These findings indicate that the differences between the beneficial effects of KA-1 and KA-2 may be explained by the markedly higher peripheral KYNA levels following KA-2 pretreatment. Targeting the peripheral component of trigeminal pain processing would provide an option for drug design which might prove beneficial in headache conditions.
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Affiliation(s)
- Gábor Veres
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Semmelweis u. 6, 6725, Szeged, Hungary.,MTA-SZTE Neuroscience Research Group, Szeged, Hungary
| | - Annamária Fejes-Szabó
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Semmelweis u. 6, 6725, Szeged, Hungary
| | - Dénes Zádori
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Semmelweis u. 6, 6725, Szeged, Hungary
| | - Gábor Nagy-Grócz
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Semmelweis u. 6, 6725, Szeged, Hungary.,Faculty of Health Sciences and Social Studies, University of Szeged, Szeged, Hungary
| | - Anna M László
- Department of Biometrics and Agricultural Informatics, Faculty of Horticultural Science, Szent Istvan University, Budapest, Hungary
| | - Attila Bajtai
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Semmelweis u. 6, 6725, Szeged, Hungary
| | - István Mándity
- Institute of Pharmaceutical Chemistry, University of Szeged, Szeged, Hungary
| | - Márton Szentirmai
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Semmelweis u. 6, 6725, Szeged, Hungary
| | - Zsuzsanna Bohár
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Semmelweis u. 6, 6725, Szeged, Hungary.,MTA-SZTE Neuroscience Research Group, Szeged, Hungary
| | - Klaudia Laborc
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Semmelweis u. 6, 6725, Szeged, Hungary
| | - István Szatmári
- Institute of Pharmaceutical Chemistry, University of Szeged, Szeged, Hungary
| | - Ferenc Fülöp
- Institute of Pharmaceutical Chemistry, University of Szeged, Szeged, Hungary
| | - László Vécsei
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Semmelweis u. 6, 6725, Szeged, Hungary. .,MTA-SZTE Neuroscience Research Group, Szeged, Hungary.
| | - Árpád Párdutz
- Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Center, University of Szeged, Semmelweis u. 6, 6725, Szeged, Hungary
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14
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Varga N, Csapó E, Majláth Z, Ilisz I, Krizbai IA, Wilhelm I, Knapp L, Toldi J, Vécsei L, Dékány I. Targeting of the kynurenic acid across the blood-brain barrier by core-shell nanoparticles. Eur J Pharm Sci 2016; 86:67-74. [PMID: 26924227 DOI: 10.1016/j.ejps.2016.02.012] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 01/29/2016] [Accepted: 02/21/2016] [Indexed: 11/26/2022]
Abstract
Core-shell nanoparticles (CSNPs) were developed to get over therapeutic amount of kynurenic acid (KYNA) across the blood-brain barrier (BBB). Bovine serum albumin (BSA) was used as core for encapsulation of KYNA and the BSA/KYNA composite was finally encapsulated by poly(allylamine) hydrochloride (PAH) polymer as shell. In the interest of the optimization of the synthesis the BSA and KYNA interaction was studied by two-dimensional surface plasmon resonance (SPR) technique as well. The average size of d~100 nm was proven by dynamic light scattering (DLS) and transmission electron microscopy (TEM), while the structure of the composites was characterized by fluorescence (FL) and circular dichroism (CD) spectroscopy. The in vitro release properties of KYNA were investigated by a vertical diffusion cell at 25.0 °C and 37.5 °C and the kinetic of the release were discussed. The penetration capacity of the NPs into the central nervous system (CNS) was tested by an in vitro BBB model. The results demonstrated that the encapsulated KYNA had significantly higher permeability compared to free KYNA molecules. In the neurobiological serial of in vivo experiments the effects of peripherally administered KYNA with CSNPs were studied in comparison with untreated KYNA. These results clearly proved that KYNA in the CSNPs, administrated peripherally is suitable to cross the BBB and to induce electrophysiological effects within the CNS. As the neuroprotective properties of KYNA nowadays are proven, the importance of the results is obvious.
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Affiliation(s)
- N Varga
- MTA-SZTE Supramolecular and Nanostructured Materials Research Group, Department of Medical Chemistry, Faculty of Medicine, University of Szeged, H-6720 Dóm tér 8, Szeged, Hungary
| | - E Csapó
- MTA-SZTE Supramolecular and Nanostructured Materials Research Group, Department of Medical Chemistry, Faculty of Medicine, University of Szeged, H-6720 Dóm tér 8, Szeged, Hungary
| | - Z Majláth
- Department of Neurology, University of Szeged, H-6725 Semmelweis u. 6, Szeged, Hungary
| | - I Ilisz
- Department of Inorganic and Analytical Chemistry, University of Szeged, H-6720 Dóm tér 7, Szeged, Hungary
| | - I A Krizbai
- Institute of Biophysics, Biological Research Centre of the Hungarian Academy of Sciences, H-6726 Temesvári krt. 62, Szeged, Hungary
| | - I Wilhelm
- Institute of Biophysics, Biological Research Centre of the Hungarian Academy of Sciences, H-6726 Temesvári krt. 62, Szeged, Hungary
| | - L Knapp
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, H-6726 Közép fasor 52, Szeged, Hungary
| | - J Toldi
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, H-6726 Közép fasor 52, Szeged, Hungary; MTA-SZTE Neuroscience Research Group, H-6725 Semmelweis u. 6, Szeged, Hungary
| | - L Vécsei
- Department of Neurology, University of Szeged, H-6725 Semmelweis u. 6, Szeged, Hungary; Department of Physiology, Anatomy and Neuroscience, University of Szeged, H-6726 Közép fasor 52, Szeged, Hungary
| | - I Dékány
- MTA-SZTE Supramolecular and Nanostructured Materials Research Group, Department of Medical Chemistry, Faculty of Medicine, University of Szeged, H-6720 Dóm tér 8, Szeged, Hungary.
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15
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Kassai F, Kedves R, Gyertyán I, Tuka B, Fülöp F, Toldi J, Lendvai B, Vécsei L. Effect of a kynurenic acid analog on home-cage activity and body temperature in rats. Pharmacol Rep 2015; 67:1188-92. [PMID: 26481540 DOI: 10.1016/j.pharep.2015.04.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 04/20/2015] [Accepted: 04/24/2015] [Indexed: 11/17/2022]
Abstract
BACKGROUND N-(2-N,N-Dimethylaminoethyl)-4-oxo-1H-quinoline-2-carboxamide hydrochloride (SzR-72) is a kynurenic acid (KYNA) amide analog that displays neuroprotective action. Whereas its brain penetration ability and its solubility limit the therapeutic use of KYNA: the corresponding properties of the analog exceed those of the parent compound. Although SzR-72 has been extensively studied, its exact mechanism of action has not yet been fully clarified. As KYNA induces hypothermia in laboratory rodents, it may be hypothesized that SzR-72 may have a similar effect. This would be of major importance, since the hypothermia generated by external cooling is neuroprotective, thus a putative hypothermic effect of SzR-72 could contribute to its neuroprotective action. METHODS The effects of SzR-72 on the body temperature and home-cage activity of rats were studied by using a telemetry system. In order to follow the longitudinal changes in the effects of the compound, subchronic drug administration was applied. RESULTS The initial administration of the compound induced substantial hypothermia and reduced the home-cage activity. During the 5 days of SzR-72 administration, partial tolerance developed to the hypothermic effect, while the inhibition of home-cage activity detected after the acute administration was completely tolerated. CONCLUSIONS On the basis of these results, it cannot be excluded that the hypothermic effect of SzR-72 contributes to its neuroprotective action.
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Affiliation(s)
- Ferenc Kassai
- Gedeon Richter Plc, Pharmacology and Drug Safety Department, Budapest, Hungary; MTA SE NAP B Cognitive Translational Behavioral Pharmacology Group, Budapest, Hungary.
| | - Rita Kedves
- Gedeon Richter Plc, Pharmacology and Drug Safety Department, Budapest, Hungary
| | - István Gyertyán
- Gedeon Richter Plc, Pharmacology and Drug Safety Department, Budapest, Hungary; MTA SE NAP B Cognitive Translational Behavioral Pharmacology Group, Budapest, Hungary
| | - Bernadett Tuka
- MTA-SZTE Neuroscience Research Group, University of Szeged, Szeged, Hungary
| | - Ferenc Fülöp
- Institute of Pharmaceutical Chemistry and Stereochemistry Research Group of the Hungarian Academy of Sciences, University of Szeged, Szeged, Hungary
| | - József Toldi
- Department of Physiology, Anatomy and Neuroscience, University of Szeged, Szeged, Hungary
| | - Balázs Lendvai
- Gedeon Richter Plc, Pharmacology and Drug Safety Department, Budapest, Hungary
| | - László Vécsei
- MTA-SZTE Neuroscience Research Group, University of Szeged, Szeged, Hungary; Department of Neurology, Faculty of Medicine, Albert Szent-Györgyi Clinical Centre, University of Szeged, Szeged, Hungary
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16
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Stone TW, Darlington LG. The kynurenine pathway as a therapeutic target in cognitive and neurodegenerative disorders. Br J Pharmacol 2014; 169:1211-27. [PMID: 23647169 DOI: 10.1111/bph.12230] [Citation(s) in RCA: 180] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 04/16/2013] [Accepted: 04/24/2013] [Indexed: 02/06/2023] Open
Abstract
Understanding the neurochemical basis for cognitive function is one of the major goals of neuroscience, with a potential impact on the diagnosis, prevention and treatment of a range of psychiatric and neurological disorders. In this review, the focus will be on a biochemical pathway that remains under-recognized in its implications for brain function, even though it can be responsible for moderating the activity of two neurotransmitters fundamentally involved in cognition - glutamate and acetylcholine. Since this pathway - the kynurenine pathway of tryptophan metabolism - is induced by immunological activation and stress, it also stands in a unique position to mediate the effects of environmental factors on cognition and behaviour. Targeting the pathway for new drug development could, therefore, be of value not only for the treatment of existing psychiatric conditions, but also for preventing the development of cognitive disorders in response to environmental pressures.
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Affiliation(s)
- Trevor W Stone
- Institute of Neuroscience & Psychology, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow, UK.
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17
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Majláth Z, Toldi J, Vécsei L. The potential role of kynurenines in Alzheimer's disease: pathomechanism and therapeutic possibilities by influencing the glutamate receptors. J Neural Transm (Vienna) 2013; 121:881-9. [PMID: 24346138 DOI: 10.1007/s00702-013-1135-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 12/03/2013] [Indexed: 12/14/2022]
Abstract
The pathomechanism of neurodegenerative disorders still poses a challenge to neuroscientists, and continuous research is under way with the aim of attaining an understanding of the exact background of these devastating diseases. The pathomechanism of Alzheimer's disease (AD) is associated with characteristic neuropathological features such as extracellular amyloid-β and intracellular tau deposition. Glutamate excitotoxicity and neuroinflammation are also factors that are known to contribute to the neurodegenerative process, but a cerebrovascular dysfunction has recently also been implicated in AD. Current therapeutic tools offer moderate symptomatic treatment, but fail to reduce disease progression. The kynurenine pathway (KP) has been implicated in the development of neurodegenerative processes, and alterations in the KP have been demonstrated in both acute and chronic neurological disorders. Kynurenines have been suggested to be involved in the regulation of neurotransmission and in immunological processes. Targeting the KP, therefore, offers a valuable strategic option for the attenuation of glutamatergic excitotoxicity, and for neuroprotection.
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Affiliation(s)
- Zsófia Majláth
- Department of Neurology, University of Szeged, Semmelweis u. 6, Szeged, 6725, Hungary
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18
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Paradox effects of kynurenines on LTP induction in the Wistar rat. An in vivo study. Neurosci Lett 2013; 553:138-41. [PMID: 23978510 DOI: 10.1016/j.neulet.2013.08.028] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 08/05/2013] [Accepted: 08/14/2013] [Indexed: 11/20/2022]
Abstract
Kynurenic acid (KYNA), a neuroactive metabolite of tryptophan that acts on different receptors (e.g. those of N-methyl-D-aspartate (NMDA) and presynaptic α7 nicotinic acetylcholine (nACh)), exerts fundamentally antiglutamatergic effects. In view of its antiglutamatergic properties, an elevation of the KYNA level within the brain might result in neuroprotection. However, the use of KYNA as a neuroprotective agent is rather limited, because it crosses the blood-brain barrier (BBB) to only a poor extent. During recent years, new KYNA derivatives have been developed which can readily traverse the BBB and also exert neuroprotection. However, as KYNA and its derivatives are able to interfere with glutamatergic and cholinergic transmission, the potential risks of interfering with cognitive functions cannot be excluded. This in vivo study on anesthetized rats therefore tested the effects of the administration of KYNA and a KYNA derivative (SZR72) (in a dosage that exerted neuroprotection) on long-term potentiation (LTP) and pure field excitatory postsynaptic potentials induced by contralateral CA3 region stimulation and recorded in the pyramidal layer of the CA1 region of the hippocampus. Surprisingly, KYNA and this derivative did not reduce, but rather increased the induceability of LTP. The possible explanation is discussed in detail. In brief: an elevated KYNA level in the perisynaptic area produced, for example, by exogenous prodrug or derivative administration exerts preferential effects on the extrasynaptic NMDA receptors and the nACh receptors on presynaptic glutamatergic terminals, while sparing the currents mediated by synaptic NMDA and α-amino-3-hydroxy-5-methyl-4-isoxazoleproprionic acid receptors. This might be the explanation why the treatment with the prodrug of KYNA or the KYNA derivative in a dosage which induced neuroprotection did not reduce the cognitive functions or the LTP.
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