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Joghataei MT, Bakhtiarzadeh F, Dehghan S, Ketabforoush AHME, Golab F, Zarbakhsh S, Ahmadirad N. The role of neurotransmitters in glioblastoma multiforme-associated seizures. Int J Dev Neurosci 2023; 83:677-690. [PMID: 37563091 DOI: 10.1002/jdn.10294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 07/20/2023] [Accepted: 07/26/2023] [Indexed: 08/12/2023] Open
Abstract
GBM, or glioblastoma multiforme, is a brain tumor that poses a great threat to both children and adults, being the primary cause of death related to brain tumors. GBM is often associated with epilepsy, which can be debilitating. Seizures and the development of epilepsy are the primary symptoms that have a severe impact on the quality of life for GBM patients. It is increasingly apparent that the nervous system plays an essential role in the tumor microenvironment for all cancer types, including GBM. In recent years, there has been a growing understanding of how neurotransmitters control the progression of gliomas. Evidence suggests that neurotransmitters and neuromodulators found in the tumor microenvironment play crucial roles in the excitability, proliferation, quiescence, and differentiation of neurons, glial cells, and neural stem cells. The involvement of neurotransmitters appears to play a significant role in various stages of GBM. In this review, the focus is on presenting updated knowledge and emerging ideas regarding the interplay between neurotransmitters and neuromodulators, such as glutamate, GABA, norepinephrine, dopamine, serotonin, adenosine, and their relationship with GBM and the seizures induced by this condition. The review aims to explore the current understanding and provide new insights into the complex interactions between these neurotransmitters and neuromodulators in the context of GBM-related seizures.
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Affiliation(s)
| | - Fatemeh Bakhtiarzadeh
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Samaneh Dehghan
- Eye Research Center, The Five Senses Institute, Rasool Akram Hospital, Iran University of Medical Sciences, Tehran, Iran
- Stem Cell and Regenerative Medicine Research Center, Iran University of Medical Sciences, Tehran, Iran
| | | | - Fereshteh Golab
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Sam Zarbakhsh
- Nervous System Stem Cells Research Center, Semnan University of Medical Sciences, Semnan, Iran
| | - Nooshin Ahmadirad
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
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Vincenzi F, Pasquini S, Contri C, Cappello M, Nigro M, Travagli A, Merighi S, Gessi S, Borea PA, Varani K. Pharmacology of Adenosine Receptors: Recent Advancements. Biomolecules 2023; 13:1387. [PMID: 37759787 PMCID: PMC10527030 DOI: 10.3390/biom13091387] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 09/05/2023] [Accepted: 09/12/2023] [Indexed: 09/29/2023] Open
Abstract
Adenosine receptors (ARs) are widely acknowledged pharmacological targets yet are still underutilized in clinical practice. Their ubiquitous distribution in almost all cells and tissues of the body makes them, on the one hand, excellent candidates for numerous diseases, and on the other hand, intrinsically challenging to exploit selectively and in a site-specific manner. This review endeavors to comprehensively depict the substantial advancements witnessed in recent years concerning the development of drugs that modulate ARs. Through preclinical and clinical research, it has become evident that the modulation of ARs holds promise for the treatment of numerous diseases, including central nervous system disorders, cardiovascular and metabolic conditions, inflammatory and autoimmune diseases, and cancer. The latest studies discussed herein shed light on novel mechanisms through which ARs exert control over pathophysiological states. They also introduce new ligands and innovative strategies for receptor activation, presenting compelling evidence of efficacy along with the implicated signaling pathways. Collectively, these emerging insights underscore a promising trajectory toward harnessing the therapeutic potential of these multifaceted targets.
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Affiliation(s)
- Fabrizio Vincenzi
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (C.C.); (M.C.); (M.N.); (A.T.); (S.M.); (S.G.); (K.V.)
| | - Silvia Pasquini
- Department of Chemical, Pharmaceutical and Agricultural Sciences, University of Ferrara, 44121 Ferrara, Italy;
| | - Chiara Contri
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (C.C.); (M.C.); (M.N.); (A.T.); (S.M.); (S.G.); (K.V.)
| | - Martina Cappello
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (C.C.); (M.C.); (M.N.); (A.T.); (S.M.); (S.G.); (K.V.)
| | - Manuela Nigro
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (C.C.); (M.C.); (M.N.); (A.T.); (S.M.); (S.G.); (K.V.)
| | - Alessia Travagli
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (C.C.); (M.C.); (M.N.); (A.T.); (S.M.); (S.G.); (K.V.)
| | - Stefania Merighi
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (C.C.); (M.C.); (M.N.); (A.T.); (S.M.); (S.G.); (K.V.)
| | - Stefania Gessi
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (C.C.); (M.C.); (M.N.); (A.T.); (S.M.); (S.G.); (K.V.)
| | | | - Katia Varani
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (C.C.); (M.C.); (M.N.); (A.T.); (S.M.); (S.G.); (K.V.)
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3
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Purnell B, Murugan M, Jani R, Boison D. The Good, the Bad, and the Deadly: Adenosinergic Mechanisms Underlying Sudden Unexpected Death in Epilepsy. Front Neurosci 2021; 15:708304. [PMID: 34321997 PMCID: PMC8311182 DOI: 10.3389/fnins.2021.708304] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 06/17/2021] [Indexed: 01/07/2023] Open
Abstract
Adenosine is an inhibitory modulator of neuronal excitability. Neuronal activity results in increased adenosine release, thereby constraining excessive excitation. The exceptionally high neuronal activity of a seizure results in a surge in extracellular adenosine to concentrations many-fold higher than would be observed under normal conditions. In this review, we discuss the multifarious effects of adenosine signaling in the context of epilepsy, with emphasis on sudden unexpected death in epilepsy (SUDEP). We describe and categorize the beneficial, detrimental, and potentially deadly aspects of adenosine signaling. The good or beneficial characteristics of adenosine signaling in the context of seizures include: (1) its direct effect on seizure termination and the prevention of status epilepticus; (2) the vasodilatory effect of adenosine, potentially counteracting postictal vasoconstriction; (3) its neuroprotective effects under hypoxic conditions; and (4) its disease modifying antiepileptogenic effect. The bad or detrimental effects of adenosine signaling include: (1) its capacity to suppress breathing and contribute to peri-ictal respiratory dysfunction; (2) its contribution to postictal generalized EEG suppression (PGES); (3) the prolonged increase in extracellular adenosine following spreading depolarization waves may contribute to postictal neuronal dysfunction; (4) the excitatory effects of A2A receptor activation is thought to exacerbate seizures in some instances; and (5) its potential contributions to sleep alterations in epilepsy. Finally, the adverse effects of adenosine signaling may potentiate a deadly outcome in the form of SUDEP by suppressing breathing and arousal in the postictal period. Evidence from animal models suggests that excessive postictal adenosine signaling contributes to the pathophysiology of SUDEP. The goal of this review is to discuss the beneficial, harmful, and potentially deadly roles that adenosine plays in the context of epilepsy and to identify crucial gaps in knowledge where further investigation is necessary. By better understanding adenosine dynamics, we may gain insights into the treatment of epilepsy and the prevention of SUDEP.
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Affiliation(s)
- Benton Purnell
- Department of Neurosurgery, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, United States
| | - Madhuvika Murugan
- Department of Neurosurgery, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, United States
| | - Raja Jani
- Department of Neurosurgery, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, United States
| | - Detlev Boison
- Department of Neurosurgery, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, United States
- Rutgers Neurosurgery H.O.P.E. Center, Department of Neurosurgery, Rutgers University, New Brunswick, NJ, United States
- Brain Health Institute, Rutgers University, Piscataway, NJ, United States
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4
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Beamer E, Kuchukulla M, Boison D, Engel T. ATP and adenosine-Two players in the control of seizures and epilepsy development. Prog Neurobiol 2021; 204:102105. [PMID: 34144123 DOI: 10.1016/j.pneurobio.2021.102105] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 04/07/2021] [Accepted: 06/09/2021] [Indexed: 02/08/2023]
Abstract
Despite continuous advances in understanding the underlying pathogenesis of hyperexcitable networks and lowered seizure thresholds, the treatment of epilepsy remains a clinical challenge. Over one third of patients remain resistant to current pharmacological interventions. Moreover, even when effective in suppressing seizures, current medications are merely symptomatic without significantly altering the course of the disease. Much effort is therefore invested in identifying new treatments with novel mechanisms of action, effective in drug-refractory epilepsy patients, and with the potential to modify disease progression. Compelling evidence has demonstrated that the purines, ATP and adenosine, are key mediators of the epileptogenic process. Extracellular ATP concentrations increase dramatically under pathological conditions, where it functions as a ligand at a host of purinergic receptors. ATP, however, also forms a substrate pool for the production of adenosine, via the action of an array of extracellular ATP degrading enzymes. ATP and adenosine have assumed largely opposite roles in coupling neuronal excitability to energy homeostasis in the brain. This review integrates and critically discusses novel findings regarding how ATP and adenosine control seizures and the development of epilepsy. This includes purine receptor P1 and P2-dependent mechanisms, release and reuptake mechanisms, extracellular and intracellular purine metabolism, and emerging receptor-independent effects of purines. Finally, possible purine-based therapeutic strategies for seizure suppression and disease modification are discussed.
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Affiliation(s)
- Edward Beamer
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, University of Medicine and Health Sciences, Dublin D02 YN77, Ireland; Centre for Bioscience, Manchester Metropolitan University, John Dalton Building, All Saints Campus, Manchester M15 6BH, UK
| | - Manvitha Kuchukulla
- Department of Neurosurgery, Robert Wood Johnson & New Jersey Medical Schools, Rutgers University, Piscataway, NJ 08854, USA
| | - Detlev Boison
- Department of Neurosurgery, Robert Wood Johnson & New Jersey Medical Schools, Rutgers University, Piscataway, NJ 08854, USA.
| | - Tobias Engel
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, University of Medicine and Health Sciences, Dublin D02 YN77, Ireland; FutureNeuro, Science Foundation Ireland Research Centre for Chronic and Rare Neurological Diseases, Royal College of Surgeons in Ireland, University of Medicine and Health Sciences, Dublin D02 YN77, Ireland.
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5
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Spanoghe J, Larsen LE, Craey E, Manzella S, Van Dycke A, Boon P, Raedt R. The Signaling Pathways Involved in the Anticonvulsive Effects of the Adenosine A 1 Receptor. Int J Mol Sci 2020; 22:ijms22010320. [PMID: 33396826 PMCID: PMC7794785 DOI: 10.3390/ijms22010320] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 12/22/2020] [Accepted: 12/27/2020] [Indexed: 12/20/2022] Open
Abstract
Adenosine acts as an endogenous anticonvulsant and seizure terminator in the brain. Many of its anticonvulsive effects are mediated through the activation of the adenosine A1 receptor, a G protein-coupled receptor with a wide array of targets. Activating A1 receptors is an effective approach to suppress seizures. This review gives an overview of the neuronal targets of the adenosine A1 receptor focusing in particular on signaling pathways resulting in neuronal inhibition. These include direct interactions of G protein subunits, the adenyl cyclase pathway and the phospholipase C pathway, which all mediate neuronal hyperpolarization and suppression of synaptic transmission. Additionally, the contribution of the guanyl cyclase and mitogen-activated protein kinase cascades to the seizure-suppressing effects of A1 receptor activation are discussed. This review ends with the cautionary note that chronic activation of the A1 receptor might have detrimental effects, which will need to be avoided when pursuing A1 receptor-based epilepsy therapies.
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Affiliation(s)
- Jeroen Spanoghe
- 4Brain, Department of Head and Skin, Ghent University, 9000 Ghent, Belgium; (J.S.); (L.E.L.); (E.C.); (S.M.); (P.B.)
| | - Lars E. Larsen
- 4Brain, Department of Head and Skin, Ghent University, 9000 Ghent, Belgium; (J.S.); (L.E.L.); (E.C.); (S.M.); (P.B.)
| | - Erine Craey
- 4Brain, Department of Head and Skin, Ghent University, 9000 Ghent, Belgium; (J.S.); (L.E.L.); (E.C.); (S.M.); (P.B.)
| | - Simona Manzella
- 4Brain, Department of Head and Skin, Ghent University, 9000 Ghent, Belgium; (J.S.); (L.E.L.); (E.C.); (S.M.); (P.B.)
| | - Annelies Van Dycke
- Department of Neurology, General Hospital Sint-Jan Bruges, 8000 Bruges, Belgium;
| | - Paul Boon
- 4Brain, Department of Head and Skin, Ghent University, 9000 Ghent, Belgium; (J.S.); (L.E.L.); (E.C.); (S.M.); (P.B.)
| | - Robrecht Raedt
- 4Brain, Department of Head and Skin, Ghent University, 9000 Ghent, Belgium; (J.S.); (L.E.L.); (E.C.); (S.M.); (P.B.)
- Correspondence:
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6
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Ho SY, Chen IC, Chang KC, Lin HR, Tsai CW, Lin CJ, Liou HH. Equilibrative Nucleoside Transporters-1 Inhibitors Act as Anti-epileptic Agents by Inhibiting Glutamatergic Transmission. Front Neurosci 2020; 14:610898. [PMID: 33390891 PMCID: PMC7773772 DOI: 10.3389/fnins.2020.610898] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 11/30/2020] [Indexed: 01/08/2023] Open
Abstract
Background and Purpose: Adenosine dysregulation is associated with the occurrence of the epilepsy and equilibrative nucleoside transporters-1 (ENT-1) functions as an important regulator of extracellular adenosine in the brain. This study was aimed to prove the anti-epileptic effect of BBB permeable ENT-1 inhibitors, JMF1907 and J4, on animal models of various epilepsy, and the mechanisms that are involved. Experimental Approach: Maximal electroshock seizure (MES), pentylenetetrazol (PTZ)-induced seizure and kindling models were used as mouse models of generalized tonic-clonic epilepsy, generalized myoclonic epilepsy, and partial epilepsy, respectively. The epilepsy frequency, duration, and Racine score were evaluated. Whole-cell recordings were made from the hippocampal dentate granule cells by using a patch-clamp technique in the brain slice of the mice. Key Results: In MES, JMF1907 at a dose of 5 mg kg-1 was efficacious in decreasing hindlimb extension, while J4 did not decrease hindlimb extension until a higher dose (10 mg kg-1). Both JMF1907 and J4 were more potent in lengthening onset latency than ethosuximide (ETH) in PTZ-induced myoclonic epilepsy model, whereas ETH had better effects on the Racine score. In kindling model, JMF1907 and J4 at a dose of 1 mg kg-1 had effects on seizure frequency and duration, and the effects of JMF1907 were comparable with those of carbamazepine. Both JMF1907 and J4 can reduce the glutamatergic spontaneous excitatory post-synaptic currents (sEPSCs) frequency. The maximal inhibition was about 50% for JMF1907 at a concentration of 1 μg L-1, whereas J4 only inhibited 40% of sEPSCs frequency at a dose of 10 μg L-1. Conclusion and Implications: ENT-1 inhibitors, JMF1907 and J4, showed anti-epileptic effects in different epilepsy models and the effects involved pre-synaptic neuronal modulation.
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Affiliation(s)
- Shih-Yin Ho
- Department of Neurology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan.,Department of Pharmacology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - I-Chun Chen
- Department of Pharmacology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Kai-Chieh Chang
- Department of Neurology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan.,National Taiwan University Hospital Yunlin Branch, Douliu, Taiwan
| | - Hsiao-Ru Lin
- School of Pharmacy, National Taiwan University, Taipei, Taiwan
| | - Che-Wen Tsai
- Department of Pharmacology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Chun-Jung Lin
- School of Pharmacy, National Taiwan University, Taipei, Taiwan
| | - Horng-Huei Liou
- Department of Neurology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan.,Department of Pharmacology, College of Medicine, National Taiwan University, Taipei, Taiwan.,National Taiwan University Hospital Yunlin Branch, Douliu, Taiwan
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7
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Zhou X, Chen Q, Huang H, Zhang J, Wang J, Chen Y, Peng Y, Zhang H, Zeng J, Feng Z, Xu Z. Inhibition of p38 MAPK regulates epileptic severity by decreasing expression levels of A1R and ENT1. Mol Med Rep 2020; 22:5348-5357. [PMID: 33174009 PMCID: PMC7647013 DOI: 10.3892/mmr.2020.11614] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 09/08/2020] [Indexed: 12/16/2022] Open
Abstract
Epilepsy is a chronic nervous system disease. Excessive increase of the excitatory neurotransmitter glutamate in the body results in an imbalance of neurotransmitters and excessive excitation of neurons, leading to epileptic seizures. Long‑term recurrent seizures lead to behavior and cognitive changes, and even increase the risk of death by 2‑ to 3‑fold relative to the general population. Adenosine A1 receptor (A1R), a member of the adenosine system, has notable anticonvulsant effects, and adenosine levels are controlled by the type 1 equilibrative nucleoside transporter (ENT1); in addition the p38 MAPK signaling pathway is involved in the regulation of ENT1, although the effect of its inhibitors on the expression levels of A1R and ENT1 is unclear. Therefore, in the present study, SB203580 was used to inhibit the p38 MAPK signaling pathway in rats, and the expression levels of A1R and ENT1 in the brain tissue of rats with acute LiCl‑pilocarpine‑induced status epilepticus was detected. SB203580 decreased pathological damage of hippocampal neurons, prolonged seizure latency, reduced the frequency of seizures, and decreased levels of A1R and ENT1 protein in rats.
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Affiliation(s)
- Xuejiao Zhou
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Qian Chen
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Hao Huang
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Jun Zhang
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Jing Wang
- Department of Prevention and Health Care, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Ya Chen
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Yan Peng
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Haiqing Zhang
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Junwei Zeng
- Department of Physiology, Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
| | - Zhanhui Feng
- Department of Neurology, Affiliated Hospital of Guizhou Medical University, Guiyang, Guizhou 550004, P.R. China
| | - Zucai Xu
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou 563003, P.R. China
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8
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Pons-Bennaceur A, Tsintsadze V, Bui TT, Tsintsadze T, Minlebaev M, Milh M, Scavarda D, Giniatullin R, Giniatullina R, Shityakov S, Wright M, Miller AD, Lozovaya N, Burnashev N. Diadenosine-Polyphosphate Analogue AppCH2ppA Suppresses Seizures by Enhancing Adenosine Signaling in the Cortex. Cereb Cortex 2020; 29:3778-3795. [PMID: 30295710 DOI: 10.1093/cercor/bhy257] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 08/15/2018] [Accepted: 09/14/2018] [Indexed: 01/16/2023] Open
Abstract
Epilepsy is a multifactorial disorder associated with neuronal hyperexcitability that affects more than 1% of the human population. It has long been known that adenosine can reduce seizure generation in animal models of epilepsies. However, in addition to various side effects, the instability of adenosine has precluded its use as an anticonvulsant treatment. Here we report that a stable analogue of diadenosine-tetraphosphate: AppCH2ppA effectively suppresses spontaneous epileptiform activity in vitro and in vivo in a Tuberous Sclerosis Complex (TSC) mouse model (Tsc1+/-), and in postsurgery cortical samples from TSC human patients. These effects are mediated by enhanced adenosine signaling in the cortex post local neuronal adenosine release. The released adenosine induces A1 receptor-dependent activation of potassium channels thereby reducing neuronal excitability, temporal summation, and hypersynchronicity. AppCH2ppA does not cause any disturbances of the main vital autonomous functions of Tsc1+/- mice in vivo. Therefore, we propose this compound to be a potent new candidate for adenosine-related treatment strategies to suppress intractable epilepsies.
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Affiliation(s)
- Alexandre Pons-Bennaceur
- INSERM UMR1249, Mediterranean Institute of Neurobiology (INMED), Aix-Marseille University, Parc Scientifique de Luminy, Marseille, France
| | - Vera Tsintsadze
- INSERM UMR1249, Mediterranean Institute of Neurobiology (INMED), Aix-Marseille University, Parc Scientifique de Luminy, Marseille, France.,Knight Cardiovascular Institute, Oregon Health and Science University, OR, USA
| | - Thi-Thien Bui
- B&A Therapeutics, Ben-Ari Institute of Neuroarcheology, Batiment Beret-Delaage, Zone Luminy Biotech Entreprises, Marseille, Cedex 09, France
| | - Timur Tsintsadze
- INSERM UMR1249, Mediterranean Institute of Neurobiology (INMED), Aix-Marseille University, Parc Scientifique de Luminy, Marseille, France
| | - Marat Minlebaev
- INSERM UMR1249, Mediterranean Institute of Neurobiology (INMED), Aix-Marseille University, Parc Scientifique de Luminy, Marseille, France.,Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia
| | - Mathieu Milh
- APHM, Department of Pediatric Neurosurgery and Neurology, CHU Timone, Marseille Cedex 5, France
| | - Didier Scavarda
- APHM, Department of Pediatric Neurosurgery and Neurology, CHU Timone, Marseille Cedex 5, France
| | - Rashid Giniatullin
- Laboratory of Neurobiology, Kazan Federal University, Kazan, Russia.,A.I. Virtanen Institute for Molecular Sciences, Department of Neurobiology, University of Eastern Finland, Kuopio, Finland
| | - Raisa Giniatullina
- A.I. Virtanen Institute for Molecular Sciences, Department of Neurobiology, University of Eastern Finland, Kuopio, Finland
| | - Sergey Shityakov
- Department of Anaesthesia and Critical Care, University of Würzburg, Josef-Schneider-Street 2, Würzburg, Germany
| | - Michael Wright
- School of Cancer and Pharmaceutical Sciences, King's College London, Franklin-Wilkins Building, Waterloo Campus, 150 Stamford Street, London, UK
| | - Andrew D Miller
- School of Cancer and Pharmaceutical Sciences, King's College London, Franklin-Wilkins Building, Waterloo Campus, 150 Stamford Street, London, UK.,Veterinary Research Institute, Hudcova 296/70, Brno, Czech Republic.,KP Therapeutics Ltd, 86 Deansgate, Manchester, UK
| | - Natalia Lozovaya
- B&A Therapeutics, Ben-Ari Institute of Neuroarcheology, Batiment Beret-Delaage, Zone Luminy Biotech Entreprises, Marseille, Cedex 09, France
| | - Nail Burnashev
- INSERM UMR1249, Mediterranean Institute of Neurobiology (INMED), Aix-Marseille University, Parc Scientifique de Luminy, Marseille, France
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9
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Activity- and pH-dependent adenosine shifts at the end of a focal seizure in the entorhinal cortex. Epilepsy Res 2020; 165:106401. [PMID: 32599416 DOI: 10.1016/j.eplepsyres.2020.106401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 06/05/2020] [Accepted: 06/14/2020] [Indexed: 11/24/2022]
Abstract
Adenosine (ADO) is an endogenous modulator of neuronal excitability, with anticonvulsant and neuroprotective effects. It has been proposed that the activity-dependent release of ADO promoted by the extracellular acidification occurring during seizures contributes to seizure termination. To verify this hypothesis, we recorded field potentials, pH and ADO changes measured with enzymatic biosensors during acute focal seizures in the medial entorhinal cortex (mEC) of the isolated guinea-pig brain maintained in vitro. The effect of ADO on seizure-like events (SLEs) induced by GABAa receptor antagonism with bicuculline methiodide (BMI; 50 μM) was assessed by arterial applications of 1 mM ADO. ADO either reduced or prevented epileptiform activity. The A1 receptor antagonist DPCPX (100-500 μM) prolonged BMI-induced seizures and was able to precipitate SLEs in the absence of proconvulsant. Simultaneous recordings of brain activity, extracellular ADO and pH shifts demonstrated that ADO decreases at the onset and progressively rises toward the end of SLEs induced by either BMI or 4-aminopyridine (4AP; 50 μM), reaching maximal values 1-5 min after SLE termination. ADO changes were preceded by a SLE-dependent extracellular acid shift. Both pH acidification and ADO changes were abolished by 22 mM HEPES in the arterial perfusate. In these conditions, SLE duration was prolonged. Our data confirm that ADO plays a role in regulating brain excitability. Its increase depends on seizure-induced acid pH shift and it is maximal after the end of the SLE. These findings strongly suggest that ADO contributes to termination of focal seizures and to the establishment of the postictal depression.
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10
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The adenosine A1 receptor agonist WAG 994 suppresses acute kainic acid-induced status epilepticus in vivo. Neuropharmacology 2020; 176:108213. [PMID: 32615188 DOI: 10.1016/j.neuropharm.2020.108213] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 06/10/2020] [Accepted: 06/12/2020] [Indexed: 12/22/2022]
Abstract
Status epilepticus (SE) is a neurological emergency characterized by continuous seizure activity lasting longer than 5 min, often with no recovery between seizures (Trinka et al., 2015). SE is refractory to benzodiazepine and second-line treatments in about 30% cases. Novel treatment approaches are urgently needed as refractory SE is associated with mortality rates of up to 70%. Robust adenosinergic anticonvulsant effects have been known for decades, but translation into seizure treatments was hampered by cardiovascular side effects. However, the selective adenosine A1 receptor agonist SDZ WAG 994 (WAG) displays diminished cardiovascular side effects compared to classic A1R agonists and was safely administered systemically in human clinical trials. Here, we investigate the anticonvulsant efficacy of WAG in vitro and in vivo. WAG robustly inhibited high-K+-induced continuous epileptiform activity in rat hippocampal slices (IC50 = 52.5 nM). Importantly, WAG acutely suppressed SE in vivo induced by kainic acid (20 mg/kg i.p.) in mice. After SE was established, mice received three i.p. injections of WAG or diazepam (DIA, 5 mg/kg). Interestingly, DIA did not attenuate SE while the majority of WAG-treated mice (1 mg/kg) were seizure-free after three injections. Anticonvulsant effects were retained when a lower dose of WAG (0.3 mg/kg) was used. Importantly, all WAG-treated mice survived kainic acid induced SE. In summary, we report for the first time that an A1R agonist with an acceptable human side-effect profile can acutely suppress established SE in vivo. Our results suggest that WAG stops or vastly attenuates SE while DIA fails to mitigate SE in this model.
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11
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Effendi WI, Nagano T, Kobayashi K, Nishimura Y. Focusing on Adenosine Receptors as a Potential Targeted Therapy in Human Diseases. Cells 2020; 9:E785. [PMID: 32213945 PMCID: PMC7140859 DOI: 10.3390/cells9030785] [Citation(s) in RCA: 83] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 03/21/2020] [Accepted: 03/23/2020] [Indexed: 02/07/2023] Open
Abstract
Adenosine is involved in a range of physiological and pathological effects through membrane-bound receptors linked to G proteins. There are four subtypes of adenosine receptors, described as A1AR, A2AAR, A2BAR, and A3AR, which are the center of cAMP signal pathway-based drug development. Several types of agonists, partial agonists or antagonists, and allosteric substances have been synthesized from these receptors as new therapeutic drug candidates. Research efforts surrounding A1AR and A2AAR are perhaps the most enticing because of their concentration and affinity; however, as a consequence of distressing conditions, both A2BAR and A3AR levels might accumulate. This review focuses on the biological features of each adenosine receptor as the basis of ligand production and describes clinical studies of adenosine receptor-associated pharmaceuticals in human diseases.
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Affiliation(s)
- Wiwin Is Effendi
- Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan; (W.I.E.); (K.K.); (Y.N.)
- Department of Pulmonology and Respiratory Medicine, Medical Faculty of Airlangga University, Surabaya 60131, Indonesia
| | - Tatsuya Nagano
- Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan; (W.I.E.); (K.K.); (Y.N.)
| | - Kazuyuki Kobayashi
- Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan; (W.I.E.); (K.K.); (Y.N.)
| | - Yoshihiro Nishimura
- Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan; (W.I.E.); (K.K.); (Y.N.)
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12
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Li J, Hong X, Li G, Conti PS, Zhang X, Chen K. PET Imaging of Adenosine Receptors in Diseases. Curr Top Med Chem 2019; 19:1445-1463. [PMID: 31284861 DOI: 10.2174/1568026619666190708163407] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 01/26/2019] [Accepted: 02/02/2019] [Indexed: 01/08/2023]
Abstract
Adenosine receptors (ARs) are a class of purinergic G-protein-coupled receptors (GPCRs). Extracellular adenosine is a pivotal regulation molecule that adjusts physiological function through the interaction with four ARs: A1R, A2AR, A2BR, and A3R. Alterations of ARs function and expression have been studied in neurological diseases (epilepsy, Alzheimer's disease, and Parkinson's disease), cardiovascular diseases, cancer, and inflammation and autoimmune diseases. A series of Positron Emission Tomography (PET) probes for imaging ARs have been developed. The PET imaging probes have provided valuable information for diagnosis and therapy of diseases related to alterations of ARs expression. This review presents a concise overview of various ARs-targeted radioligands for PET imaging in diseases. The most recent advances in PET imaging studies by using ARs-targeted probes are briefly summarized.
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Affiliation(s)
- Jindian Li
- Department of Radiology, Molecular Imaging Center, Keck School of Medicine, University of Southern California, 2250 Alcazar Street, CSC103, Los Angeles, CA 90033, United States.,State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics & Center for Molecular Imaging and Translational Medicine, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Xingfang Hong
- Laboratory of Pathogen Biology, School of Basic Medical Sciences, Dali University, Dali 671000, China
| | - Guoquan Li
- Department of Radiology, Molecular Imaging Center, Keck School of Medicine, University of Southern California, 2250 Alcazar Street, CSC103, Los Angeles, CA 90033, United States
| | - Peter S Conti
- Department of Radiology, Molecular Imaging Center, Keck School of Medicine, University of Southern California, 2250 Alcazar Street, CSC103, Los Angeles, CA 90033, United States
| | - Xianzhong Zhang
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics & Center for Molecular Imaging and Translational Medicine, School of Public Health, Xiamen University, Xiamen 361102, China
| | - Kai Chen
- Department of Radiology, Molecular Imaging Center, Keck School of Medicine, University of Southern California, 2250 Alcazar Street, CSC103, Los Angeles, CA 90033, United States
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13
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Zavala-Tecuapetla C, Orozco-Suarez S, Manjarrez J, Cuellar-Herrera M, Vega-Garcia A, Buzoianu-Anguiano V. Activation of adenosine receptors modulates the efflux transporters in brain capillaries and restores the anticonvulsant effect of carbamazepine in carbamazepine resistant rats developed by window-pentylenetetrazole kindling. Brain Res 2019; 1726:146516. [PMID: 31634453 DOI: 10.1016/j.brainres.2019.146516] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 10/15/2019] [Accepted: 10/17/2019] [Indexed: 01/14/2023]
Abstract
Up-regulation of efflux transporters in brain capillaries may lead to the decreased therapeutic efficacy of antiepileptic drugs in patients with Drug Resistant Epilepsy. Adenosine receptor activation in brain capillaries can modulate blood-brain barrier permeability by decreasing the protein levels and function of efflux transporters. Therefore, we aimed to investigate whether the activation of adenosine receptors improves convulsions outcome in carbamazepine (CBZ) resistant animals and modulates the protein levels of efflux transporters (P-GP, MRP1, MRP2) in brain capillaries. We employed the window-pentylenetetrazol (PTZ) kindling model to develop CBZ resistant rats by CBZ administration during the post-kindling phase, and tested if these animals displayed subsequent resistance to other antiepileptic drugs. Crucially, we investigated if the administration of a broad-spectrum adenosine agonist (NECA) improves convulsions control in CBZ resistant rats. Of potential therapeutic relevance, in CBZ resistant rats NECA restored the anticonvulsant effect of CBZ. We also evaluated how the resistance to CBZ and the activation of adenosine receptors with NECA affect protein levels of efflux transporters in brain capillaries, as quantified by western blot. While CBZ resistance was associated with the up-regulation of both P-GP/MRP2 in brain capillaries, with the administration of NECA in CBZ resistant rats, we observed a decrease of P-GP and an increase of MRP2 levels, in brain capillaries. Since the activation of adenosine receptors improves the outcome of convulsions probably through the modulation of the efflux transporters protein levels in brain capillaries, adenosine agonists could be useful as an adjunct therapy for the control of Drug Resistant Epilepsy.
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Affiliation(s)
- C Zavala-Tecuapetla
- Laboratory of Physiology of Reticular Formation, National Institute of Neurology and Neurosurgery, Insurgentes Sur 3877, La Fama, 14269 Mexico City, Mexico.
| | - S Orozco-Suarez
- Medical Research Unit in Neurological Diseases, Specialty Hospital, National Medical Center XXI Century, IMSS, Cuauhtemoc 330, Doctores, 06720 Mexico City, Mexico
| | - J Manjarrez
- Laboratory of Physiology of Reticular Formation, National Institute of Neurology and Neurosurgery, Insurgentes Sur 3877, La Fama, 14269 Mexico City, Mexico
| | - M Cuellar-Herrera
- Epilepsy Clinic, Hospital General de México, Dr. Eduardo Liceaga, Dr. Balmis 148, Doctores, 06720 Mexico City, Mexico
| | - A Vega-Garcia
- Medical Research Unit in Neurological Diseases, Specialty Hospital, National Medical Center XXI Century, IMSS, Cuauhtemoc 330, Doctores, 06720 Mexico City, Mexico; Department of Physiology, Faculty of Medicine, National Autonomous University of Mexico, Av. Universidad 3000, C.U., 04510 Mexico City, Mexico
| | - V Buzoianu-Anguiano
- Medical Research Unit in Neurological Diseases, Specialty Hospital, National Medical Center XXI Century, IMSS, Cuauhtemoc 330, Doctores, 06720 Mexico City, Mexico
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Weltha L, Reemmer J, Boison D. The role of adenosine in epilepsy. Brain Res Bull 2019; 151:46-54. [PMID: 30468847 PMCID: PMC6527499 DOI: 10.1016/j.brainresbull.2018.11.008] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 11/01/2018] [Accepted: 11/15/2018] [Indexed: 12/13/2022]
Abstract
Adenosine is a well-characterized endogenous anticonvulsant and seizure terminator of the brain. Through a combination of adenosine receptor-dependent and -independent mechanisms, adenosine affects seizure generation (ictogenesis), as well as the development of epilepsy and its progression (epileptogenesis). Maladaptive changes in adenosine metabolism, in particular increased expression of the astroglial enzyme adenosine kinase (ADK), play a major role in epileptogenesis. Increased expression of ADK has dual roles in both reducing the inhibitory tone of adenosine in the brain, which consequently reduces the threshold for seizure generation, and also driving an increased flux of methyl-groups through the transmethylation pathway, thereby increasing global DNA methylation. Through these mechanisms, adenosine is uniquely positioned to link metabolism with epigenetic outcome. Therapeutic adenosine augmentation therefore not only holds promise for the suppression of seizures in epilepsy, but moreover the prevention of epilepsy and its progression overall. This review will focus on adenosine-related mechanisms implicated in ictogenesis and epileptogenesis and will discuss therapeutic opportunities and challenges.
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Affiliation(s)
- Landen Weltha
- Robert Stone Dow Neurobiology Laboratories, Legacy Research Institute, Portland, OR, USA
| | - Jesica Reemmer
- Robert Stone Dow Neurobiology Laboratories, Legacy Research Institute, Portland, OR, USA
| | - Detlev Boison
- Robert Stone Dow Neurobiology Laboratories, Legacy Research Institute, Portland, OR, USA.
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Inhibition of T-Type calcium channels in mEC layer II stellate neurons reduces neuronal hyperexcitability associated with epilepsy. Epilepsy Res 2019; 154:132-138. [PMID: 31132598 DOI: 10.1016/j.eplepsyres.2019.05.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 05/01/2019] [Accepted: 05/07/2019] [Indexed: 01/20/2023]
Abstract
Temporal lobe epilepsy (TLE) is a form of adult epilepsy involving the entorhinal cortex (EC). Layer II neurons of the medial EC (mEC) are spared and become hyperexcitable in TLE. Studies have suggested a role for T-type calcium channels (T-type Ca2+ channels) in facilitating increases in neuronal activity associated with TLE within the hippocampus. We sought to determine if T-type Ca2+ channels play a role in facilitating neuronal hyperexcitability of layer II mEC stellate neurons in TLE. TLE was induced in rats by electrical stimulation of the hippocampus to induce status epilepticus (SE). Brain slices were prepared from rats exhibiting spontaneous seizures and compared with age-matched control rats. Action potentials (APs) were evoked either by current injection steps or via presynaptic stimulation of mEC deep layers. The selective T-type Ca2+ channel antagonist, TTA-P2 (1 μM), was applied to determine the role of T-type Ca2+ channels in maintaining neuronal excitability. Quantitative PCR techniques were used to assess T-type Ca2+ channel isoform mRNA levels within the mEC layer II. TLE mEC layer II stellate neurons were hyperexcitable compared to control neurons, evoking a higher frequency of APs and generating bursts of APs when synaptically stimulated. TTA-P2 (1 μM) reduced firing frequencies in TLE and control neurons and reduced AP burst firing in TLE stellate neurons. TTA-P2 had little effect on synaptically evoked AP's in control neurons. TTA-P2 also inhibited rebound APs evoked in TLE neurons to a greater degree than in control neurons. TLE tissue had almost a 3-fold increase in Cav3.1 mRNA compared to controls. Cav3.2 or Cav3.3 levels were unchanged. These findings support a role for T-type Ca2+ channel in establishing neuronal hyperexcitability of mEC layer II stellate neurons in TLE. Increased expression of Cav3.1 may be important for establishing neuronal hyperexcitability of mEC layer II neurons in TLE.
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16
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Borea PA, Gessi S, Merighi S, Vincenzi F, Varani K. Pharmacology of Adenosine Receptors: The State of the Art. Physiol Rev 2018; 98:1591-1625. [PMID: 29848236 DOI: 10.1152/physrev.00049.2017] [Citation(s) in RCA: 455] [Impact Index Per Article: 75.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Adenosine is a ubiquitous endogenous autacoid whose effects are triggered through the enrollment of four G protein-coupled receptors: A1, A2A, A2B, and A3. Due to the rapid generation of adenosine from cellular metabolism, and the widespread distribution of its receptor subtypes in almost all organs and tissues, this nucleoside induces a multitude of physiopathological effects, regulating central nervous, cardiovascular, peripheral, and immune systems. It is becoming clear that the expression patterns of adenosine receptors vary among cell types, lending weight to the idea that they may be both markers of pathologies and useful targets for novel drugs. This review offers an overview of current knowledge on adenosine receptors, including their characteristic structural features, molecular interactions and cellular functions, as well as their essential roles in pain, cancer, and neurodegenerative, inflammatory, and autoimmune diseases. Finally, we highlight the latest findings on molecules capable of targeting adenosine receptors and report which stage of drug development they have reached.
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Affiliation(s)
- Pier Andrea Borea
- Department of Medical Sciences, University of Ferrara , Ferrara , Italy
| | - Stefania Gessi
- Department of Medical Sciences, University of Ferrara , Ferrara , Italy
| | - Stefania Merighi
- Department of Medical Sciences, University of Ferrara , Ferrara , Italy
| | - Fabrizio Vincenzi
- Department of Medical Sciences, University of Ferrara , Ferrara , Italy
| | - Katia Varani
- Department of Medical Sciences, University of Ferrara , Ferrara , Italy
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17
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Zhang J, Chen X, Kårbø M, Zhao Y, An L, Wang R, Wang K, Huang Z. Anticonvulsant effect of dipropofol by enhancing native GABA currents in cortical neurons in mice. J Neurophysiol 2018; 120:1404-1414. [DOI: 10.1152/jn.00241.2018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Temporal lobe epilepsy (TLE), the most common pharmacoresistant focal epilepsy disorder, remains a major unmet medical need. Propofol is used as a short-acting medication for general anesthesia and refractory status epilepticus with issues of decreased consciousness and memory loss. Dipropofol, a derivative of propofol, has been reported to exert antioxidative and antibacterial activities. Here we report that dipropofol exerted anticonvulsant activity in a mouse model of kainic acid-induced seizures. Whole cell patch-clamp recordings of brain slices from the medial entorhinal cortex (mEC) revealed that dipropofol hyperpolarized the resting membrane potential and reduced the number of action potential firings, resulting in suppression of cortical neuronal excitability. Furthermore, dipropofol activated native tonic GABAA currents of mEC layer II stellate neurons in a dose-dependent manner with an EC50 value of 9.3 ± 1.6 μM (mean ± SE). Taken together, our findings show that dipropofol activated GABAA currents and exerted anticonvulsant activities in mice, thus possessing developmental potential for new anticonvulsant therapy. NEW & NOTEWORTHY The anticonvulsant effect of dipropofol was shown in a mouse model of kainic acid-induced seizures. Whole cell patch-clamp recordings of brain slices showed suppression of cortical neuronal excitability by dipropofol. Dipropofol activated the native tonic GABAA currents in a dose-dependent manner.
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Affiliation(s)
- Jingliang Zhang
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing, China
| | - Xiaoling Chen
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing, China
| | - Matti Kårbø
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing, China
| | - Yi Zhao
- Tech-Development Department, Xi’an Libang Pharmaceutical Company, Xi’an, China
| | - Long An
- Tech-Development Department, Xi’an Libang Pharmaceutical Company, Xi’an, China
| | - Rutao Wang
- Tech-Development Department, Xi’an Libang Pharmaceutical Company, Xi’an, China
| | - KeWei Wang
- Department of Pharmacology, Qingdao University School of Pharmacy, Qingdao, China
| | - Zhuo Huang
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing, China
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18
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Luan G, Wang X, Gao Q, Guan Y, Wang J, Deng J, Zhai F, Chen Y, Li T. Upregulation of Neuronal Adenosine A1 Receptor in Human Rasmussen Encephalitis. J Neuropathol Exp Neurol 2017; 76:720-731. [DOI: 10.1093/jnen/nlx053] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
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19
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Klaft ZJ, Hollnagel JO, Salar S, Calişkan G, Schulz SB, Schneider UC, Horn P, Koch A, Holtkamp M, Gabriel S, Gerevich Z, Heinemann U. Adenosine A1 receptor-mediated suppression of carbamazepine-resistant seizure-like events in human neocortical slices. Epilepsia 2016; 57:746-56. [PMID: 27087530 DOI: 10.1111/epi.13360] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/18/2016] [Indexed: 02/02/2023]
Abstract
OBJECTIVE The need for alternative pharmacologic strategies in treatment of epilepsies is pressing for about 30% of patients with epilepsy who do not experience satisfactory seizure control with present treatments. In temporal lobe epilepsy (TLE) even up to 80% of patients are pharmacoresistant, and surgical resection of the ictogenic tissue is only possible for a minority of TLE patients. In this study we investigate purinergic modulation of drug-resistant seizure-like events (SLEs) in human temporal cortex slices. METHODS Layer V/VI field potentials from a total of 77 neocortical slices from 17 pharmacoresistant patients were recorded to monitor SLEs induced by application of 8 mM [K(+) ] and 50 μm bicuculline. RESULTS Activating A1 receptors with a specific agonist completely suppressed SLEs in 73% of human temporal cortex slices. In the remaining slices, incidence of SLEs was markedly reduced. Because a subportion of slices can be pharmacosensitive, we tested effects of an A1 agonist, in slices insensitive to a high dose of carbamazepine (50 μm). Also in these cases the A1 agonist was equally efficient. Moreover, ATP and adenosine blocked or modulated SLEs, an effect mediated not by P2 receptors but rather by adenosine A1 receptors. SIGNIFICANCE Selective activation of A1 receptors mediates a strong anticonvulsant action in human neocortical slices from pharmacoresistant patients. We propose that our human slice model of seizure-like activity is a feasible option for future studies investigating new antiepileptic drug (AED) candidates.
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Affiliation(s)
- Zin-Juan Klaft
- Institute of Neurophysiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Jan-Oliver Hollnagel
- Institute of Neurophysiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Seda Salar
- Institute of Neurophysiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Gürsel Calişkan
- Institute of Neurophysiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Steffen B Schulz
- Institute of Neurophysiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Ulf C Schneider
- Department of Neurosurgery, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Peter Horn
- Department of Neurosurgery, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Arend Koch
- Department of Neuropathology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Martin Holtkamp
- Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Epilepsy-Center Berlin-Brandenburg, Krankenhaus Königin Elisabeth Herzberge, Berlin, Germany
| | - Siegrun Gabriel
- Institute of Neurophysiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Zoltan Gerevich
- Institute of Neurophysiology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Uwe Heinemann
- Institute of Neurophysiology, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Neuroscience Research Center, Charité - Universitätsmedizin Berlin, Berlin, Germany
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Differential Expression of Adenosine P1 Receptor ADORA1 and ADORA2A Associated with Glioma Development and Tumor-Associated Epilepsy. Neurochem Res 2016; 41:1774-83. [PMID: 27038930 DOI: 10.1007/s11064-016-1893-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Revised: 03/03/2016] [Accepted: 03/17/2016] [Indexed: 12/12/2022]
Abstract
Level of adenosine, an endogenous astrocyte-based neuromodulator, is primarily regulated by adenosine P1 receptors. This study assessed expression of adenosine P1 receptors, ADORA1 (adenosine A1 receptor) and ADORA2A (adenosine A2a receptor) and their association with glioma development and epilepsy in glioma patients. Expression of ADORA1/ADORA2A was assessed immunohistochemically in 65 surgically removed glioma tissue and 21 peri-tumor tissues and 8 cases of normal brain tissues obtained from hematoma patients with cerebral trauma. Immunofluorescence, Western blot, and qRT-PCR were also used to verify immunohistochemical data. Adenosine P1 receptor ADORA1 and ADORA2A proteins were localized in the cell membrane and cytoplasm and ADORA1/ADORA2A immunoreactivity was significantly stronger in glioma and peri-tumor tissues that contained infiltrating tumor cells than in normal brain tissues (p < 0.05). The World Health Organization (WHO) grade III gliomas expressed even higher level of ADORA1 and ADORA2A. Western blot and qRT-PCR confirmed immunohistochemical data. Moreover, higher levels of ADORA1 and ADORA2A expression occurred in high-grade gliomas, in which incidence of epilepsy were lower (p < 0.05). In contrast, a lower level of ADORA1/ADORA2A expression was found in peri-tumor tissues with tumor cell presence from patients with epilepsy compared to patients without epilepsy (p < 0.05). The data from the current study indicates that dysregulation in ADORA1/ADORA2A expression was associated with glioma development, whereas low level of ADORA1/ADORA2A expression could increase susceptibility of tumor-associated epilepsy.
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21
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Borea PA, Gessi S, Merighi S, Varani K. Adenosine as a Multi-Signalling Guardian Angel in Human Diseases: When, Where and How Does it Exert its Protective Effects? Trends Pharmacol Sci 2016; 37:419-434. [PMID: 26944097 DOI: 10.1016/j.tips.2016.02.006] [Citation(s) in RCA: 203] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 02/08/2016] [Accepted: 02/09/2016] [Indexed: 12/20/2022]
Abstract
The importance of adenosine for human health cannot be overstated. Indeed, this ubiquitous nucleoside is an integral component of ATP, and regulates the function of every tissue and organ in the body. Acting via receptor-dependent and -independent mechanisms [the former mediated via four G-protein-coupled receptors (GPCRs), A1, A2A, A2B, and A3,], it has a significant role in protecting against cell damage in areas of increased tissue metabolism, and combating organ dysfunction in numerous pathological states. Accordingly, raised levels of adenosine have been demonstrated in epilepsy, ischaemia, pain, inflammation, and cancer, in which its behaviour can be likened to that of a guardian angel, even though there are instances in which overproduction of adenosine is pathological. In this review, we condense the current body of knowledge on the issue, highlighting when, where, and how adenosine exerts its protective effects in both the brain and the periphery.
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Affiliation(s)
- Pier Andrea Borea
- Department of Medical Sciences, Pharmacology Section, University of Ferrara, Via Fossato di Mortara, 17-19, 44121 Ferrara, Italy.
| | - Stefania Gessi
- Department of Medical Sciences, Pharmacology Section, University of Ferrara, Via Fossato di Mortara, 17-19, 44121 Ferrara, Italy.
| | - Stefania Merighi
- Department of Medical Sciences, Pharmacology Section, University of Ferrara, Via Fossato di Mortara, 17-19, 44121 Ferrara, Italy.
| | - Katia Varani
- Department of Medical Sciences, Pharmacology Section, University of Ferrara, Via Fossato di Mortara, 17-19, 44121 Ferrara, Italy
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22
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Huang J, He Y, Chen M, Du J, Li G, Li S, Liu W, Long X. Adenosine deaminase and adenosine kinase expression in human glioma and their correlation with glioma‑associated epilepsy. Mol Med Rep 2015; 12:6509-16. [PMID: 26329539 PMCID: PMC4626129 DOI: 10.3892/mmr.2015.4285] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 08/05/2015] [Indexed: 12/21/2022] Open
Abstract
The aim of the present study was to investigate adenosine deaminase (ADA) and adenosine kinase (ADK) expression in human glioma and to explore its correlation with glioma-associated epilepsy. Tumor tissues (n=45) and peritumoral tissues (n=14) were obtained from glioma patients undergoing surgery. Normal control tissues (n=8) were obtained from brain trauma patients. The disease grade was determined by histological evaluation and the degree of tumor invasion was evaluated using immunofluorescence analyses. mRNA and protein expression of ADA and ADK were evaluated using reverse transcription quantitative polymerase chain reaction or western blot analysis, respectively. Based on histological evaluations, four cases were classified as Grade I gliomas, 18 cases as Grade II, 17 cases as Grade III and six cases were considered Grade IV. Increased ADA and ADK expression was observed in tumor tissues. ADA was predominantly distributed in the cytoplasm of tumor cells, whereas ADK was detected in the cytoplasm as well as in the nuclei. ADA and ADK levels were upregulated in patients with Grade II and Grade III gliomas compared to those in control subjects (p<0.05). In addition, tumor invasion was detected in peritumoral tissues. The number of ADA-positive or ADK-positive cells in tumor tissues was similar between glioma patients with and without epilepsy (p>0.05). However, ADA and ADK expression was upregulated in peritumoral tissues derived from patients with epilepsy compared to that in glioma patients without epilepsy. The results of the present study suggested that ADA and ADK are involved in glioma progression, and that increased ADA and ADK levels in peritumoral tissues may be associated with epilepsy in glioma patients.
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Affiliation(s)
- Jun Huang
- Department of Neurosurgery, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China
| | - Yujiao He
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China
| | - Mingna Chen
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China
| | - Juan Du
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China
| | - Guoliang Li
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China
| | - Shuyu Li
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China
| | - Weiping Liu
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China
| | - Xiaoyan Long
- Department of Neurology, Xiangya Hospital of Central South University, Changsha, Hunan 410008, P.R. China
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23
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Boison D. Adenosinergic signaling in epilepsy. Neuropharmacology 2015; 104:131-9. [PMID: 26341819 DOI: 10.1016/j.neuropharm.2015.08.046] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 08/27/2015] [Accepted: 08/28/2015] [Indexed: 12/12/2022]
Abstract
Despite the introduction of at least 20 new antiepileptic drugs (AEDs) into clinical practice over the past decades, about one third of all epilepsies remain refractory to conventional forms of treatment. In addition, currently used AEDs have been developed to suppress neuronal hyperexcitability, but not necessarily to address pathogenic mechanisms involved in epilepsy development or progression (epileptogenesis). For those reasons endogenous seizure control mechanisms of the brain may provide alternative therapeutic opportunities. Adenosine is a well characterized endogenous anticonvulsant and seizure terminator of the brain. Several lines of evidence suggest that endogenous adenosine-mediated seizure control mechanisms fail in chronic epilepsy, whereas therapeutic adenosine augmentation effectively prevents epileptic seizures, even those that are refractory to conventional AEDs. New findings demonstrate that dysregulation of adenosinergic mechanisms are intricately involved in the development of epilepsy and its comorbidities, whereas adenosine-associated epigenetic mechanisms may play a role in epileptogenesis. The first goal of this review is to discuss how maladaptive changes of adenosinergic mechanisms contribute to the expression of seizures (ictogenesis) and the development of epilepsy (epileptogenesis) by focusing on pharmacological (adenosine receptor dependent) and biochemical (adenosine receptor independent) mechanisms as well as on enzymatic and transport based mechanisms that control the availability (homeostasis) of adenosine. The second goal of this review is to highlight innovative adenosine-based opportunities for therapeutic intervention aimed at reconstructing normal adenosine function and signaling for improved seizure control in chronic epilepsy. New findings suggest that transient adenosine augmentation can have lasting epigenetic effects with disease modifying and antiepileptogenic outcome. This article is part of the Special Issue entitled 'Purines in Neurodegeneration and Neuroregeneration'.
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Affiliation(s)
- Detlev Boison
- Robert Stone Dow Neurobiology Laboratories, Legacy Research Institute, Portland, OR 97232, USA.
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24
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Miranda MF, Hamani C, de Almeida ACG, Amorim BO, Macedo CE, Fernandes MJS, Nobrega JN, Aarão MC, Madureira AP, Rodrigues AM, Andersen ML, Tufik S, Mello LE, Covolan L. Role of adenosine in the antiepileptic effects of deep brain stimulation. Front Cell Neurosci 2014; 8:312. [PMID: 25324724 PMCID: PMC4183090 DOI: 10.3389/fncel.2014.00312] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2014] [Accepted: 09/17/2014] [Indexed: 12/20/2022] Open
Abstract
Despite the effectiveness of anterior thalamic nucleus (AN) deep brain stimulation (DBS) for the treatment of epilepsy, mechanisms responsible for the antiepileptic effects of this therapy remain elusive. As adenosine modulates neuronal excitability and seizure activity in animal models, we hypothesized that this nucleoside could be one of the substrates involved in the effects of AN DBS. We applied 5 days of stimulation to rats rendered chronically epileptic by pilocarpine injections and recorded epileptiform activity in hippocampal slices. We found that slices from animals given DBS had reduced hippocampal excitability and were less susceptible to develop ictal activity. In live animals, AN DBS significantly increased adenosine levels in the hippocampus as measured by microdialysis. The reduced excitability of DBS in vitro was completely abolished in animals pre-treated with A1 receptor antagonists and was strongly potentiated by A1 receptor agonists. We conclude that some of the antiepileptic effects of DBS may be mediated by adenosine.
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Affiliation(s)
- Maisa F Miranda
- Laboratório de Neurociência Experimental e Computacional, Universidade Federal de São João del-Rei São João del-Rei, Brazil
| | - Clement Hamani
- Disciplina de Neurofisiologia, Universidade Federal de São Paulo São Paulo, Brazil ; Behavioural Neurobiology Laboratory, Centre for Addiction and Mental Health Toronto, Canada ; Division of Neurosurgery, Toronto Western Hospital, University of Toronto Toronto, Canada
| | - Antônio-Carlos G de Almeida
- Laboratório de Neurociência Experimental e Computacional, Universidade Federal de São João del-Rei São João del-Rei, Brazil
| | - Beatriz O Amorim
- Disciplina de Neurofisiologia, Universidade Federal de São Paulo São Paulo, Brazil
| | - Carlos E Macedo
- Departamento de Psicobiologia, Universidade Federal de São Paulo São Paulo, Brazil
| | - Maria José S Fernandes
- Disciplina de Neurologia Experimental, Universidade Federal de São Paulo São Paulo, Brazil
| | - José N Nobrega
- Behavioural Neurobiology Laboratory, Centre for Addiction and Mental Health Toronto, Canada
| | - Mayra C Aarão
- Laboratório de Neurociência Experimental e Computacional, Universidade Federal de São João del-Rei São João del-Rei, Brazil
| | - Ana Paula Madureira
- Laboratório de Neurociência Experimental e Computacional, Universidade Federal de São João del-Rei São João del-Rei, Brazil
| | - Antônio M Rodrigues
- Laboratório de Neurociência Experimental e Computacional, Universidade Federal de São João del-Rei São João del-Rei, Brazil
| | - Monica L Andersen
- Departamento de Psicobiologia, Universidade Federal de São Paulo São Paulo, Brazil
| | - Sergio Tufik
- Departamento de Psicobiologia, Universidade Federal de São Paulo São Paulo, Brazil
| | - Luiz E Mello
- Disciplina de Neurofisiologia, Universidade Federal de São Paulo São Paulo, Brazil
| | - Luciene Covolan
- Disciplina de Neurofisiologia, Universidade Federal de São Paulo São Paulo, Brazil
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25
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Bertram EH. Electrophysiology in epilepsy surgery: Roles and limitations. Ann Indian Acad Neurol 2014; 17:S40-4. [PMID: 24791088 PMCID: PMC4001233 DOI: 10.4103/0972-2327.128649] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Revised: 01/15/2014] [Accepted: 01/15/2014] [Indexed: 11/04/2022] Open
Abstract
Successful epilepsy surgery depends on the localization of the seizure onset zone in an area of the brain that can be safely resected. Defining these zones uses multiple diagnostic approaches, which include different types of electroencephalography (EEG) and imaging, and the results are best when all of the tests point to the same region. Although EEG obtained with scalp recordings is often sufficient for the purposes of localization, there are times when intracranial recordings directly from the brain are needed; but the planning, use, value, and interpretation of the these recordings are not standardized, in part because the questions that are to be answered vary considerably across many patients and their heterogenous types of epilepsy that are investigated. Furthermore, there is a desire to use the opportunity of direct brain recordings to understand the pathophysiology of epilepsy, as these recordings are viewed as an opportunity to answer questions that cannot be otherwise answered. In this review, we examine the situations that may require intracranial electrodes and discuss the broad issues that this powerful diagnostic tool can help address, for identifying the seizure focus and for understanding the large scale circuits of the seizures.
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Affiliation(s)
- Edward H Bertram
- Department of Neurology, University of Virginia, Charlottesville, Virginia, USA
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26
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Masino SA, Kawamura M, Ruskin DN. Adenosine receptors and epilepsy: current evidence and future potential. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2014; 119:233-55. [PMID: 25175969 PMCID: PMC6026023 DOI: 10.1016/b978-0-12-801022-8.00011-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Adenosine receptors are a powerful therapeutic target for regulating epileptic seizures. As a homeostatic bioenergetic network regulator, adenosine is perfectly suited to establish or restore an ongoing balance between excitation and inhibition, and its anticonvulsant efficacy is well established. There is evidence for the involvement of multiple adenosine receptor subtypes in epilepsy, but in particular the adenosine A1 receptor subtype can powerfully and bidirectionally regulate seizure activity. Mechanisms that regulate adenosine itself are increasingly appreciated as targets to thus influence receptor activity and seizure propensity. Taken together, established evidence for the powerful potential of adenosine-based epilepsy therapies and new strategies to influence receptor activity can combine to capitalize on this endogenous homeostatic neuromodulator.
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Affiliation(s)
- Susan A Masino
- Department of Psychology and Neuroscience Program, Trinity College, Hartford, Connecticut, USA.
| | - Masahito Kawamura
- Department of Pharmacology, Jikei University School of Medicine, Minato-ku, Tokyo, Japan
| | - David N Ruskin
- Department of Psychology and Neuroscience Program, Trinity College, Hartford, Connecticut, USA
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27
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Klaft ZJ, Schulz SB, Maslarova A, Gabriel S, Heinemann U, Gerevich Z. Extracellular ATP differentially affects epileptiform activity via purinergic P2X7 and adenosine A1 receptors in naive and chronic epileptic rats. Epilepsia 2012; 53:1978-86. [PMID: 23106524 DOI: 10.1111/j.1528-1167.2012.03724.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
PURPOSE Adenosine is considered an endogenous anticonvulsant. However, much less is known about the putative effects of its precursor, ATP, on epilepsy. Therefore, we tested whether ATP and its receptors are able to modulate epileptiform activity in the medial entorhinal cortex of the rat. METHODS Recurrent epileptiform discharges (REDs) were induced by elevating extracellular potassium concentration combined with application of bicuculline in brain slices from naive and pilocarpine-treated chronic epileptic rats. Field potentials were recorded from layer V/VI of the medial entorhinal cortex. KEY FINDINGS REDs in slices from naive animals had a higher incidence and a shorter duration than in slices from chronic epileptic animals. Exogenous application of ATP reversibly reduced the incidence of REDs in naive and chronic epileptic slices via activation of adenosine A(1) receptors without discernible P2 receptor effects. This effect was stronger in slices from chronic epileptic rats. In slices from naive rats, the P2X7 receptor antagonist A 740003 slightly but significantly reduced the amplitude of slow field potentials of REDs. In slices from chronic epileptic rats, none of the P2 receptor antagonists affected the parameters of REDs. SIGNIFICANCE Our results suggest that endogenously released ATP differentially modulates REDs by activation of A(1) and P2X7 receptors. Although it has a minor proepileptic effect by direct activation of P2X7 receptors, its metabolite adenosine reduces the epileptiform activity via activation of A(1) receptors. The exact effect of ATP on neural activity depends on the actual activity of ectonucleotidases and the expression level of the purinergic receptors, which both alter during epileptogenesis. In addition, our data suggest that P2X7 receptor antagonists have a minor antiepileptic effect.
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Affiliation(s)
- Zin-Juan Klaft
- Institute of Neurophysiology, Charité-Universitätsmedizin Berlin, Charitplatz 1, Berlin, Germany
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