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Heit BS, Chu A, McRay A, Richmond JE, Heckman CJ, Larson J. Interference with glutamate antiporter system x c - enables post-hypoxic long-term potentiation in hippocampus. Exp Physiol 2024. [PMID: 39153228 DOI: 10.1113/ep092045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2024] [Accepted: 06/28/2024] [Indexed: 08/19/2024]
Abstract
Our group previously showed that genetic or pharmacological inhibition of the cystine/glutamate antiporter, system xc -, mitigates excitotoxicity after anoxia by increasing latency to anoxic depolarization, thus attenuating the ischaemic core. Hypoxia, however, which prevails in the ischaemic penumbra, is a condition where neurotransmission is altered, but excitotoxicity is not triggered. The present study employed mild hypoxia to further probe ischaemia-induced changes in neuronal responsiveness from wild-type and xCT KO (xCT-/-) mice. Synaptic transmission was monitored in hippocampal slices from both genotypes before, during and after a hypoxic episode. Although wild-type and xCT-/- slices showed equal suppression of synaptic transmission during hypoxia, mutant slices exhibited a persistent potentiation upon re-oxygenation, an effect we termed 'post-hypoxic long-term potentiation (LTP)'. Blocking synaptic suppression during hypoxia by antagonizing adenosine A1 receptors did not preclude post-hypoxic LTP. Further examination of the induction and expression mechanisms of this plasticity revealed that post-hypoxic LTP was driven by NMDA receptor activation, as well as increased calcium influx, with no change in paired-pulse facilitation. Hence, the observed phenomenon engaged similar mechanisms as classical LTP. This was a remarkable finding as theta-burst stimulation-induced LTP was equivalent between genotypes. Importantly, post-hypoxic LTP was generated in wild-type slices pretreated with system xc - inhibitor, S-4-carboxyphenylglycine, thereby confirming the antiporter's role in this phenomenon. Collectively, these data indicate that system xc - interference enables neuroplasticity in response to mild hypoxia, and, together with its regulation of cellular damage in the ischaemic core, suggest a role for the antiporter in post-ischaemic recovery of the penumbra.
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Affiliation(s)
- Bradley S Heit
- Department of Neuroscience and Department of Biomedical Engineering, Northwestern University, Chicago, Illinois, USA
- Department of Psychiatry, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Alex Chu
- Department of Psychiatry, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Alyssa McRay
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Janet E Richmond
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Charles J Heckman
- Department of Neuroscience and Department of Biomedical Engineering, Northwestern University, Chicago, Illinois, USA
| | - John Larson
- Department of Psychiatry, University of Illinois at Chicago, Chicago, Illinois, USA
- Department of Biological Sciences, University of Illinois at Chicago, Chicago, Illinois, USA
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2
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Planas AM. Role of microglia in stroke. Glia 2024; 72:1016-1053. [PMID: 38173414 DOI: 10.1002/glia.24501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 12/07/2023] [Accepted: 12/19/2023] [Indexed: 01/05/2024]
Abstract
Microglia play key roles in the post-ischemic inflammatory response and damaged tissue removal reacting rapidly to the disturbances caused by ischemia and working to restore the lost homeostasis. However, the modified environment, encompassing ionic imbalances, disruption of crucial neuron-microglia interactions, spreading depolarization, and generation of danger signals from necrotic neurons, induce morphological and phenotypic shifts in microglia. This leads them to adopt a proinflammatory profile and heighten their phagocytic activity. From day three post-ischemia, macrophages infiltrate the necrotic core while microglia amass at the periphery. Further, inflammation prompts a metabolic shift favoring glycolysis, the pentose-phosphate shunt, and lipid synthesis. These shifts, combined with phagocytic lipid intake, drive lipid droplet biogenesis, fuel anabolism, and enable microglia proliferation. Proliferating microglia release trophic factors contributing to protection and repair. However, some microglia accumulate lipids persistently and transform into dysfunctional and potentially harmful foam cells. Studies also showed microglia that either display impaired apoptotic cell clearance, or eliminate synapses, viable neurons, or endothelial cells. Yet, it will be essential to elucidate the viability of engulfed cells, the features of the local environment, the extent of tissue damage, and the temporal sequence. Ischemia provides a rich variety of region- and injury-dependent stimuli for microglia, evolving with time and generating distinct microglia phenotypes including those exhibiting proinflammatory or dysfunctional traits and others showing pro-repair features. Accurate profiling of microglia phenotypes, alongside with a more precise understanding of the associated post-ischemic tissue conditions, is a necessary step to serve as the potential foundation for focused interventions in human stroke.
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Affiliation(s)
- Anna M Planas
- Cerebrovascular Research Laboratory, Department of Neuroscience and Experimental Therapeutics, Instituto de Investigaciones Biomédicas de Barcelona (IIBB), Consejo Superior de Investigaciones Científicas (CSIC), Barcelona, Spain
- Cerebrovascular Diseases, Area of Clinical and Experimental Neuroscience, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS)-Hospital Clínic, Barcelona, Spain
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Luchkanych AMS, Morse CJ, Boyes NG, Khan MR, Marshall RA, Morton JS, Tomczak CR, Olver TD. Cerebral sympatholysis: experiments on in vivo cerebrovascular regulation and ex vivo cerebral vasomotor control. Am J Physiol Heart Circ Physiol 2024; 326:H1105-H1116. [PMID: 38391313 DOI: 10.1152/ajpheart.00714.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 02/13/2024] [Accepted: 02/19/2024] [Indexed: 02/24/2024]
Abstract
Whether cerebral sympathetic-mediated vasomotor control can be modulated by local brain activity remains unknown. This study tested the hypothesis that the application or removal of a cognitive task during a cold pressor test (CPT) would attenuate and restore decreases in cerebrovascular conductance (CVC), respectively. Middle cerebral artery blood velocity (transcranial Doppler) and mean arterial pressure (finger photoplethysmography) were examined in healthy adults (n = 16; 8 females and 8 males) who completed a control CPT, followed by a CPT coupled with a cognitive task administered either 1) 30 s after the onset of the CPT and for the duration of the CPT or 2) at the onset of the CPT and terminated 30 s before the end of the CPT (condition order was counterbalanced). The major finding was that the CPT decreased the index of CVC, and such decreases were abolished when a cognitive task was completed concurrently and restored when the cognitive task was removed. As a secondary experiment, vasomotor interactions between sympathetic transduction pathways (α1-adrenergic and Y1-peptidergic) and compounds implicated in cerebral blood flow control [adenosine, and adenosine triphosphate (ATP)] were explored in isolated porcine cerebral arteries (wire myography). The data reveal α1-receptor agonism potentiated vasorelaxation modestly in response to adenosine, and preexposure to ATP attenuated contractile responses to α1-agonism. Overall, the data suggest a cognitive task attenuates decreases in CVC during sympathoexcitation, possibly related to an interaction between purinergic and α1-adrenergic signaling pathways.NEW & NOTEWORTHY The present study demonstrates that the cerebrovascular conductance index decreases during sympathoexcitation and this response can be positively and negatively modulated by the application or withdrawal of a nonexercise cognitive task. Furthermore, isolated vessel experiments reveal that cerebral α1-adrenergic agonism potentiates adenosine-mediated vasorelaxation and ATP attenuates α1-adrenergic-mediated vasocontraction.
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Affiliation(s)
- Adam M S Luchkanych
- College of Kinesiology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
- Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Cameron J Morse
- Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Natasha G Boyes
- College of Kinesiology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - M Rafique Khan
- College of Kinesiology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Rory A Marshall
- Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
- Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, British Columbia, Canada
| | - Jude S Morton
- Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Corey R Tomczak
- College of Kinesiology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - T Dylan Olver
- Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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Matsumura N, Aoyama K. Glutathione-Mediated Neuroprotective Effect of Purine Derivatives. Int J Mol Sci 2023; 24:13067. [PMID: 37685879 PMCID: PMC10487553 DOI: 10.3390/ijms241713067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 08/19/2023] [Accepted: 08/20/2023] [Indexed: 09/10/2023] Open
Abstract
Numerous basic studies have reported on the neuroprotective properties of several purine derivatives such as caffeine and uric acid (UA). Epidemiological studies have also shown the inverse association of appropriate caffeine intake or serum urate levels with neurodegenerative diseases such as Alzheimer disease (AD) and Parkinson's disease (PD). The well-established neuroprotective mechanisms of caffeine and UA involve adenosine A2A receptor antagonism and antioxidant activity, respectively. Our recent study found that another purine derivative, paraxanthine, has neuroprotective effects similar to those of caffeine and UA. These purine derivatives can promote neuronal cysteine uptake through excitatory amino acid carrier protein 1 (EAAC1) to increase neuronal glutathione (GSH) levels in the brain. This review summarizes the GSH-mediated neuroprotective effects of purine derivatives. Considering the fact that GSH depletion is a manifestation in the brains of AD and PD patients, administration of purine derivatives may be a new therapeutic approach to prevent or delay the onset of these neurodegenerative diseases.
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Affiliation(s)
- Nobuko Matsumura
- Department of Pharmacology, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi, Tokyo 173-8605, Japan
| | - Koji Aoyama
- Department of Pharmacology, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi, Tokyo 173-8605, Japan
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Venturini M, Cherchi F, Santalmasi C, Frulloni L, Dettori I, Catarzi D, Pedata F, Colotta V, Varano F, Coppi E, Pugliese AM. Pharmacological Characterization of P626, a Novel Dual Adenosine A 2A/A 2B Receptor Antagonist, on Synaptic Plasticity and during an Ischemic-like Insult in CA1 Rat Hippocampus. Biomolecules 2023; 13:894. [PMID: 37371474 DOI: 10.3390/biom13060894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 05/24/2023] [Accepted: 05/25/2023] [Indexed: 06/29/2023] Open
Abstract
In recent years, the use of multi-target compounds has become an increasingly pursued strategy to treat complex pathologies, including cerebral ischemia. Adenosine and its receptors (A1AR, A2AAR, A2BAR, A3AR) are known to play a crucial role in synaptic transmission either in normoxic or ischemic-like conditions. Previous data demonstrate that the selective antagonism of A2AAR or A2BAR delays anoxic depolarization (AD) appearance, an unequivocal sign of neuronal injury induced by a severe oxygen-glucose deprivation (OGD) insult in the hippocampus. Furthermore, the stimulation of A2AARs or A2BARs by respective selective agonists, CGS21680 and BAY60-6583, increases pre-synaptic neurotransmitter release, as shown by the decrease in paired-pulse facilitation (PPF) at Schaffer collateral-CA1 synapses. In the present research, we investigated the effect/s of the newly synthesized dual A2AAR/A2BAR antagonist, P626, in preventing A2AAR- and/or A2BAR-mediated effects by extracellular recordings of synaptic potentials in the CA1 rat hippocampal slices. We demonstrated that P626 prevented PPF reduction induced by CGS21680 or BAY60-6583 and delayed, in a concentration-dependent manner, AD appearance during a severe OGD. In conclusion, P626 may represent a putative neuroprotective compound for stroke treatment with the possible translational advantage of reducing side effects and bypassing differences in pharmacokinetics due to combined treatment.
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Affiliation(s)
- Martina Venturini
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy
| | - Federica Cherchi
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy
| | - Clara Santalmasi
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy
| | - Lucia Frulloni
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy
| | - Ilaria Dettori
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy
| | - Daniela Catarzi
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmaceutical and Nutraceutical Sciences, University of Florence, 50019 Sesto Fiorentino, Italy
| | - Felicita Pedata
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy
| | - Vittoria Colotta
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmaceutical and Nutraceutical Sciences, University of Florence, 50019 Sesto Fiorentino, Italy
| | - Flavia Varano
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmaceutical and Nutraceutical Sciences, University of Florence, 50019 Sesto Fiorentino, Italy
| | - Elisabetta Coppi
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy
| | - Anna Maria Pugliese
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy
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Schädlich IS, Winzer R, Stabernack J, Tolosa E, Magnus T, Rissiek B. The role of the ATP-adenosine axis in ischemic stroke. Semin Immunopathol 2023:10.1007/s00281-023-00987-3. [PMID: 36917241 DOI: 10.1007/s00281-023-00987-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 01/25/2023] [Indexed: 03/16/2023]
Abstract
In ischemic stroke, the primary neuronal injury caused by the disruption of energy supply is further exacerbated by secondary sterile inflammation. The inflammatory cascade is largely initiated by the purine adenosine triphosphate (ATP) which is extensively released to the interstitial space during brain ischemia and functions as an extracellular danger signaling molecule. By engaging P2 receptors, extracellular ATP activates microglia leading to cytokine and chemokine production and subsequent immune cell recruitment from the periphery which further amplifies post-stroke inflammation. The ectonucleotidases CD39 and CD73 shape and balance the inflammatory environment by stepwise degrading extracellular ATP to adenosine which itself has neuroprotective and anti-inflammatory signaling properties. The neuroprotective effects of adenosine are mainly mediated through A1 receptors and inhibition of glutamatergic excitotoxicity, while the anti-inflammatory capacities of adenosine have been primarily attributed to A2A receptor activation on infiltrating immune cells in the subacute phase after stroke. In this review, we summarize the current state of knowledge on the ATP-adenosine axis in ischemic stroke, discuss contradictory results, and point out potential pitfalls towards translating therapeutic approaches from rodent stroke models to human patients.
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Affiliation(s)
- Ines Sophie Schädlich
- Department of Neurology, University Medical Centre Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Riekje Winzer
- Institute of Immunology, University Medical Centre Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Joschi Stabernack
- Department of Neurology, University Medical Centre Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Eva Tolosa
- Institute of Immunology, University Medical Centre Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
| | - Tim Magnus
- Department of Neurology, University Medical Centre Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany.
| | - Björn Rissiek
- Department of Neurology, University Medical Centre Hamburg-Eppendorf, Martinistraße 52, 20246, Hamburg, Germany
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Purinergic signaling: a potential therapeutic target for ischemic stroke. Purinergic Signal 2023; 19:173-183. [PMID: 36370253 PMCID: PMC9984595 DOI: 10.1007/s11302-022-09905-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 10/30/2022] [Indexed: 11/15/2022] Open
Abstract
Pathogenesis of ischemic stroke is mainly characterized by thrombosis and neuroinflammation. Purinergic signaling pathway constitutes adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP), and adenosine (ADO). ATP is hydrolyzed to ADP and then to AMP by extracellular nucleotidase CD39; AMP is subsequently converted to adenosine by CD73. All these nucleotides and nucleosides act on purinergic receptors protecting against thrombosis and inhibit inflammation. In addition, many physical methods have been found to play a neuroprotective role through purinergic signaling. This review mainly introduces the role and potential mechanism of purinergic signalings in the treatment of ischemic stroke, so as to provide reference for seeking new treatment methods for stroke.
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8
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Nucleoside transporters and immunosuppressive adenosine signaling in the tumor microenvironment: Potential therapeutic opportunities. Pharmacol Ther 2022; 240:108300. [PMID: 36283452 DOI: 10.1016/j.pharmthera.2022.108300] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 10/17/2022] [Accepted: 10/19/2022] [Indexed: 11/30/2022]
Abstract
Adenosine compartmentalization has a profound impact on immune cell function by regulating adenosine localization and, therefore, extracellular signaling capabilities, which suppresses immune cell function in the tumor microenvironment. Nucleoside transporters, responsible for the translocation and cellular compartmentalization of hydrophilic adenosine, represent an understudied yet crucial component of adenosine disposition in the tumor microenvironment. In this review article, we will summarize what is known regarding nucleoside transporter's function within the purinome in relation to currently devised points of intervention (i.e., ectonucleotidases, adenosine receptors) for cancer immunotherapy, alterations in nucleoside transporter expression reported in cancer, and potential avenues for targeting of nucleoside transporters for the desired modulation of adenosine compartmentalization and action. Further, we put forward that nucleoside transporters are an unexplored therapeutic opportunity, and modulation of nucleoside transport processes could attenuate the pathogenic buildup of immunosuppressive adenosine in solid tumors, particularly those enriched with nucleoside transport proteins.
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Simulated hypoxia modulates P2X7 receptor function in mice peritoneal macrophages. Int Immunopharmacol 2022; 110:109062. [PMID: 35863257 DOI: 10.1016/j.intimp.2022.109062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 07/08/2022] [Accepted: 07/12/2022] [Indexed: 11/23/2022]
Abstract
The inflammatory focus is similar to the tumor microenvironment, which contains a complex milieu with immune cells and macrophages. The accumulation of cells promotes local pH and O2 tension decline (hypoxia). Local O2 tension decline activates hypoxia-inducible factor α and β (HIF-1α and HIF-1β adenosine triphosphate (ATP) release. ATP activates the P2X7 receptor and modulates ischemic/hypoxic conditions. Similarly, α1α may regulate P2X7 receptor expression in the hypoxic microenvironment. Therefore, we investigated P2X7 receptor function under simulated hypoxic conditions by pretreating peritoneal macrophages with mitochondrial electron transport chain complex inhibitors (simulated hypoxia). Treatment with mitochondrial electron transport chain complex inhibitors until three hours of exposure did not cause LDH release. Additionally, mitochondrial electron transport chain complex inhibitors increased ATP-induced P2X7 receptor function without being able to directly activate this receptor. Other P2 receptor subtypes do not appear to participate in this mechanism. Simulated hypoxia augmented HIF-1α levels and suppressed HIF-1α and P2X7 receptor antagonists. Similarly, simulated hypoxia increased ATP-induced dye uptake and inhibited HIF-1α antagonists. Another factor activated in simulated hypoxic conditions was the intracellular P2X7 receptor regulator PIP2. Treatment with HIF-1α agonists increased PIP2 levels and reversed the effects of HIF-1α and P2X7 receptor antagonists. Additionally, the improved ATP-induced dye uptake caused by the simulated hypoxia stimulus was inhibited by P2X7 receptor and PIP2 antagonists. Therefore, simulated hypoxia may augment P2X7 receptor activity for a pathway dependent on HIF-1α and PIP2 activation.
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Schrader J. Ectonucleotidases as bridge between the ATP and adenosine world: reflections on Geoffrey Burnstock. Purinergic Signal 2022; 18:193-198. [PMID: 35522386 PMCID: PMC9123149 DOI: 10.1007/s11302-022-09862-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 04/04/2022] [Indexed: 11/23/2022] Open
Abstract
Historically, mainly by the work of Robert Berne, extracellular adenosine was the first purine compound recognized as an important signaling molecule linking energy metabolism to function by acting on membrane bound receptors. Geoffrey Burnstock by his vision and endurance pioneered the idea that cells release ATP that also acts as an extracellular signaling molecule under many physiological and pathophysiological circumstances. Only later, it was appreciated that extracellular ATP and adenosine are metabolically linked by the activity of several ectoenzymes which critically determine the concentrations of these purines at their respective receptors. In this brief review, I will report some personal recollections on Geoffrey Burnstock and his impressive personality. In addition, I will give a brief overview on our present knowledge of extracellular purine metabolism and its control and will address some still open issues.
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Affiliation(s)
- Jürgen Schrader
- Department of Molecular Cardiology, University of Düsseldorf, Medical Faculty, Universitaetsstr. 1, 40225, Duesseldorf, Germany.
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Jia X, Xie L, Liu Y, Liu T, Yang P, Hu J, Peng Z, Luo K, Du M, Chen C. Astragalus polysaccharide (APS) exerts protective effect against acute ischemic stroke (AIS) through enhancing M2 micoglia polarization by regulating adenosine triphosphate (ATP)/ purinergic receptor (P2X7R) axis. Bioengineered 2022; 13:4468-4480. [PMID: 35166175 PMCID: PMC8973874 DOI: 10.1080/21655979.2021.1980176] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Clinically, the effective treatment for patients with acute ischemic stroke (AIS) is very limited. Therefore, this paper aims to investigate the mechanism how astragalus polysaccharide (APS) exerts protective effect against AIS and provide a new method for the treatment of AIS. Cell surface antigen flow cytometry and immunofluorescence were used to identify M1 and M2 microglia. Western blot was used to evaluate the expression of associated protein. Oxygen-glucose deprivation (OGD) was used to simulate the effect of AIS on rat microglia. The middle cerebral artery occlusion (MCAO) model was established to simulate the effect of AIS in vivo. Evans blue dye (EBD) was used to evaluate the permeability of blood–brain barrier (BBB). Western blot and cell surface antigen flow cytometry results showed that APS promoted the M2 polarization of rat microglia by inhibiting the expression of purinergic receptor (P2X7R). APS reversed the effect of OGD on the polarization of rat microglia M1/ M2 by regulating P2X7R. APS reversed the effect of MCAO on the polarization of rat microglia M1/ M2 in vivo. Furthermore, APS inhibited the expression of P2X7R by promoting the degradation of adenosine triphosphate (ATP) in the cerebral cortex of MCAO rats. In addition, APS contributed to maintain the integrity of BBB. Summarily, APS can reduce brain injury by promoting the degradation of ATP in microglia and inhibiting the expression of P2X7R after AIS.
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Affiliation(s)
- Xiang Jia
- Department of Neurology, Guangzhou Hospital of Integrated Traditional and West Medicine, Guangzhou, China
| | - Liying Xie
- Department of Neurology, Guangzhou Hospital of Integrated Traditional and West Medicine, Guangzhou, China
| | - Yuan Liu
- Department of Neurology, Guangzhou Hospital of Integrated Traditional and West Medicine, Guangzhou, China
| | - Tianfu Liu
- Department of Neurology, Guangzhou Hospital of Integrated Traditional and West Medicine, Guangzhou, China
| | - Peiqun Yang
- Department of Neurology, Guangzhou Hospital of Integrated Traditional and West Medicine, Guangzhou, China
| | - Jianfang Hu
- Department of Neurology, Guangzhou Hospital of Integrated Traditional and West Medicine, Guangzhou, China
| | - Zhichao Peng
- Department of Neurology, Guangzhou Hospital of Integrated Traditional and West Medicine, Guangzhou, China
| | - Kangrui Luo
- Department of Neurology, Guangzhou Hospital of Integrated Traditional and West Medicine, Guangzhou, China
| | - Min Du
- Nursing Department, Guangzhou Hospital of Integrated Traditional and West Medicine, Guangzhou, China
| | - Chaojun Chen
- Department of Neurology, Guangzhou Hospital of Integrated Traditional and West Medicine, Guangzhou, China
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Khaksar S, Bigdeli M, Samiee A, Shirazi-zand Z. Antioxidant and Anti-apoptotic Effects of Cannabidiol in Model of Ischemic Stroke in Rats. Brain Res Bull 2022; 180:118-130. [DOI: 10.1016/j.brainresbull.2022.01.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 11/27/2021] [Accepted: 01/05/2022] [Indexed: 12/11/2022]
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13
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Gleizes M, Fonta C, Nowak LG. Inhibitors of ectonucleotidases have paradoxical effects on synaptic transmission in the mouse cortex. J Neurochem 2021; 160:305-324. [PMID: 34905223 DOI: 10.1111/jnc.15558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 12/08/2021] [Accepted: 12/09/2021] [Indexed: 11/30/2022]
Abstract
Extracellular adenosine plays prominent roles in the brain in both physiological and pathological conditions. Adenosine can be generated following the degradation of extracellular nucleotides by various types of ectonucleotidases. Several ectonucleotidases are present in the brain parenchyma: ecto-nucleotide triphosphate diphosphohydrolases 1 and 3 (NTPDase 1 and 3), ecto-nucleotide pyrophosphatase/phosphodiesterase 1 (NPP 1), ecto-5'-nucleotidase (eN), and tissue non-specific alkaline phosphatase (TNAP, whose function in the brain has received little attention). Here we examined, in a living brain preparation, the role of these ectonucleotidases in generating extracellular adenosine. We recorded local field potentials evoked by electrical stimulation of the lateral olfactory tract in the mouse piriform cortex in vitro. Variations in adenosine level were evaluated by measuring changes in presynaptic inhibition generated by adenosine A1 receptors (A1Rs) activation. A1R-mediated presynaptic inhibition was present endogenously and was enhanced by bath-applied AMP and ATP. We hypothesized that inhibiting ectonucleotidases would reduce extracellular adenosine concentration, which would result in a weakening of presynaptic inhibition. However, inhibiting TNAP had no effect in controlling endogenous adenosine action and no effect on presynaptic inhibition induced by bath-applied AMP. Furthermore, contrary to our expectation, inhibiting TNAP reinforced, rather than reduced, presynaptic inhibition induced by bath-applied ATP. Similarly, inhibition of NTPDase 1 and 3, NPP1 and eN induced stronger, rather than weaker, presynaptic inhibition, both in endogenous condition and with bath-applied ATP and AMP. Consequently, attempts to suppress the functions of extracellular adenosine by blocking its extracellular synthesis in living brain tissue could have functional impacts opposite to those anticipated.
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Affiliation(s)
- Marie Gleizes
- CerCo, Université Toulouse 3, CNRS, CHU Purpan, Pavillon Baudot, BP 25202, 31052, Toulouse Cedex
| | - Caroline Fonta
- CerCo, Université Toulouse 3, CNRS, CHU Purpan, Pavillon Baudot, BP 25202, 31052, Toulouse Cedex
| | - Lionel G Nowak
- CerCo, Université Toulouse 3, CNRS, CHU Purpan, Pavillon Baudot, BP 25202, 31052, Toulouse Cedex
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Ganesana M, Venton BJ. Spontaneous, transient adenosine release is not enhanced in the CA1 region of hippocampus during severe ischemia models. J Neurochem 2021; 159:887-900. [PMID: 34453336 PMCID: PMC8627433 DOI: 10.1111/jnc.15496] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 08/10/2021] [Accepted: 08/11/2021] [Indexed: 12/23/2022]
Abstract
Ischemic stroke causes damage in the brain, and a slow buildup of adenosine is neuroprotective during ischemic injury. Spontaneous, transient adenosine signaling, lasting only 3 s per event, has been discovered that increases in frequency in the caudate-putamen during early stages of mild ischemia-reperfusion injury. However, spontaneous adenosine changes have not been studied in the hippocampus during ischemia, an area highly susceptible to stroke. Here, we investigated changes of spontaneous, transient adenosine in the CA1 region of rat hippocampus during three different models of the varied intensity of ischemia. During the early stages of the milder bilateral common carotid artery occlusion (BCCAO) model, there were fewer spontaneous, transient adenosine, but no change in the concentration of individual events. In contrast, during the moderate 2 vertebral artery occlusion (2VAO) and severe 4 vessel occlusion (4VO) models, both the frequency of spontaneous, transient adenosine and the average event adenosine concentration decreased. Blood flow measurements validate that the ischemia models decreased blood flow, and corresponding pathological changes were observed by transmission electron microscopy (TEM). 4VO occlusion showed the most severe damage in histology and BCCAO showed the least. Overall, our data suggest that there is no enhanced spontaneous adenosine release in the hippocampus during moderate and severe ischemia, which could be due to depletion of the rapidly releasable adenosine pool. Thus, during ischemic stroke, there are fewer spontaneous adenosine events that could inhibit neurotransmission, which might lead to more damage and less neuroprotection in the hippocampus CA1 region. Read the Editorial Highlight for this article on page 800.
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Affiliation(s)
- Mallikarjunarao Ganesana
- Department of Chemistry and Neuroscience Graduate Program, University of Virginia, Charlottesville, VA, USA
| | - B. Jill Venton
- Department of Chemistry and Neuroscience Graduate Program, University of Virginia, Charlottesville, VA, USA
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15
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Role of Purinergic Signalling in Endothelial Dysfunction and Thrombo-Inflammation in Ischaemic Stroke and Cerebral Small Vessel Disease. Biomolecules 2021; 11:biom11070994. [PMID: 34356618 PMCID: PMC8301873 DOI: 10.3390/biom11070994] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 06/28/2021] [Accepted: 07/01/2021] [Indexed: 12/20/2022] Open
Abstract
The cerebral endothelium is an active interface between blood and the central nervous system. In addition to being a physical barrier between the blood and the brain, the endothelium also actively regulates metabolic homeostasis, vascular tone and permeability, coagulation, and movement of immune cells. Being part of the blood–brain barrier, endothelial cells of the brain have specialized morphology, physiology, and phenotypes due to their unique microenvironment. Known cardiovascular risk factors facilitate cerebral endothelial dysfunction, leading to impaired vasodilation, an aggravated inflammatory response, as well as increased oxidative stress and vascular proliferation. This culminates in the thrombo-inflammatory response, an underlying cause of ischemic stroke and cerebral small vessel disease (CSVD). These events are further exacerbated when blood flow is returned to the brain after a period of ischemia, a phenomenon termed ischemia-reperfusion injury. Purinergic signaling is an endogenous molecular pathway in which the enzymes CD39 and CD73 catabolize extracellular adenosine triphosphate (eATP) to adenosine. After ischemia and CSVD, eATP is released from dying neurons as a damage molecule, triggering thrombosis and inflammation. In contrast, adenosine is anti-thrombotic, protects against oxidative stress, and suppresses the immune response. Evidently, therapies that promote adenosine generation or boost CD39 activity at the site of endothelial injury have promising benefits in the context of atherothrombotic stroke and can be extended to current CSVD known pathomechanisms. Here, we have reviewed the rationale and benefits of CD39 and CD39 therapies to treat endothelial dysfunction in the brain.
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16
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Kim KJ, Diaz JR, Presa JL, Muller PR, Brands MW, Khan MB, Hess DC, Althammer F, Stern JE, Filosa JA. Decreased parenchymal arteriolar tone uncouples vessel-to-neuronal communication in a mouse model of vascular cognitive impairment. GeroScience 2021; 43:1405-1422. [PMID: 33410092 PMCID: PMC8190257 DOI: 10.1007/s11357-020-00305-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 11/22/2020] [Indexed: 01/18/2023] Open
Abstract
Chronic hypoperfusion is a key contributor to cognitive decline and neurodegenerative conditions, but the cellular mechanisms remain ill-defined. Using a multidisciplinary approach, we sought to elucidate chronic hypoperfusion-evoked functional changes at the neurovascular unit. We used bilateral common carotid artery stenosis (BCAS), a well-established model of vascular cognitive impairment, combined with an ex vivo preparation that allows pressurization of parenchymal arterioles in a brain slice. Our results demonstrate that mild (~ 30%), chronic hypoperfusion significantly altered the functional integrity of the cortical neurovascular unit. Although pial cerebral perfusion recovered over time, parenchymal arterioles progressively lost tone, exhibiting significant reductions by day 28 post-surgery. We provide supportive evidence for reduced adenosine 1 receptor-mediated vasoconstriction as a potential mechanism in the adaptive response underlying the reduced baseline tone in parenchymal arterioles. In addition, we show that in response to the neuromodulator adenosine, the action potential frequency of cortical pyramidal neurons was significantly reduced in all groups. However, a significant decrease in adenosine-induced hyperpolarization was observed in BCAS 14 days. At the microvascular level, constriction-induced inhibition of pyramidal neurons was significantly compromised in BCAS mice. Collectively, these results suggest that BCAS uncouples vessel-to-neuron communication-vasculo-neuronal coupling-a potential early event in cognitive decline.
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Affiliation(s)
- Ki Jung Kim
- Department of Physiology, Augusta University, Augusta, GA, 30912, USA
| | - Juan Ramiro Diaz
- Department of Physiology, Augusta University, Augusta, GA, 30912, USA
| | - Jessica L Presa
- Department of Physiology, Augusta University, Augusta, GA, 30912, USA
| | - P Robinson Muller
- Department of Physiology, Augusta University, Augusta, GA, 30912, USA
| | - Michael W Brands
- Department of Physiology, Augusta University, Augusta, GA, 30912, USA
| | - Mohammad B Khan
- Department of Neurology, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - David C Hess
- Department of Neurology, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | | | - Javier E Stern
- Neuroscience Institute, Georgia State University, Atlanta, GA, USA
| | - Jessica A Filosa
- Department of Physiology, Augusta University, Augusta, GA, 30912, USA.
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17
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Pereira-Figueiredo D, Nascimento AA, Cunha-Rodrigues MC, Brito R, Calaza KC. Caffeine and Its Neuroprotective Role in Ischemic Events: A Mechanism Dependent on Adenosine Receptors. Cell Mol Neurobiol 2021; 42:1693-1725. [PMID: 33730305 DOI: 10.1007/s10571-021-01077-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Accepted: 03/05/2021] [Indexed: 02/07/2023]
Abstract
Ischemia is characterized by a transient, insufficient, or permanent interruption of blood flow to a tissue, which leads to an inadequate glucose and oxygen supply. The nervous tissue is highly active, and it closely depends on glucose and oxygen to satisfy its metabolic demand. Therefore, ischemic conditions promote cell death and lead to a secondary wave of cell damage that progressively spreads to the neighborhood areas, called penumbra. Brain ischemia is one of the main causes of deaths and summed with retinal ischemia comprises one of the principal reasons of disability. Although several studies have been performed to investigate the mechanisms of damage to find protective/preventive interventions, an effective treatment does not exist yet. Adenosine is a well-described neuromodulator in the central nervous system (CNS), and acts through four subtypes of G-protein-coupled receptors. Adenosine receptors, especially A1 and A2A receptors, are the main targets of caffeine in daily consumption doses. Accordingly, caffeine has been greatly studied in the context of CNS pathologies. In fact, adenosine system, as well as caffeine, is involved in neuroprotection effects in different pathological situations. Therefore, the present review focuses on the role of adenosine/caffeine in CNS, brain and retina, ischemic events.
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Affiliation(s)
- D Pereira-Figueiredo
- Neurobiology of the Retina Laboratory, Biomedical Sciences Program, Biomedical Institute, Fluminense Federal University, Niterói, RJ, Brazil
| | - A A Nascimento
- Neurobiology of the Retina Laboratory, Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, RJ, Brazil
| | - M C Cunha-Rodrigues
- Neurobiology of the Retina Laboratory, Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, RJ, Brazil
| | - R Brito
- Laboratory of Neuronal Physiology and Pathology, Cellular and Molecular Biology Department, Institute of Biology, Fluminense Federal University, Niterói, RJ, Brazil
| | - K C Calaza
- Neurobiology of the Retina Laboratory, Biomedical Sciences Program, Biomedical Institute, Fluminense Federal University, Niterói, RJ, Brazil. .,Neurobiology of the Retina Laboratory, Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, RJ, Brazil. .,Neurobiology Department, Biology Institute of Fluminense Federal University, Niteroi, RJ, Brazil.
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18
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Joya A, Ardaya M, Montilla A, Garbizu M, Plaza-García S, Gómez-Vallejo V, Padro D, Gutiérrez JJ, Rios X, Ramos-Cabrer P, Cossío U, Pulagam KR, Higuchi M, Domercq M, Cavaliere F, Matute C, Llop J, Martín A. In vivo multimodal imaging of adenosine A 1 receptors in neuroinflammation after experimental stroke. Theranostics 2021; 11:410-425. [PMID: 33391483 PMCID: PMC7681082 DOI: 10.7150/thno.51046] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 09/24/2020] [Indexed: 01/21/2023] Open
Abstract
Adenosine A1 receptors (A1ARs) are promising imaging biomarkers and targets for the treatment of stroke. Nevertheless, the role of A1ARs on ischemic damage and its subsequent neuroinflammatory response has been scarcely explored so far. Methods: In this study, the expression of A1ARs after transient middle cerebral artery occlusion (MCAO) was evaluated by positron emission tomography (PET) with [18F]CPFPX and immunohistochemistry (IHC). In addition, the role of A1ARs on stroke inflammation using pharmacological modulation was assessed with magnetic resonance imaging (MRI), PET imaging with [18F]DPA-714 (TSPO) and [18F]FLT (cellular proliferation), as well as IHC and neurofunctional studies. Results: In the ischemic territory, [18F]CPFPX signal and IHC showed the overexpression of A1ARs in microglia and infiltrated leukocytes after cerebral ischemia. Ischemic rats treated with the A1AR agonist ENBA showed a significant decrease in both [18F]DPA-714 and [18F]FLT signal intensities at day 7 after cerebral ischemia, a feature that was confirmed by IHC results. Besides, the activation of A1ARs promoted the reduction of the brain lesion, as measured with T2W-MRI, and the improvement of neurological outcome including motor, sensory and reflex responses. These results show for the first time the in vivo PET imaging of A1ARs expression after cerebral ischemia in rats and the application of [18F]FLT to evaluate glial proliferation in response to treatment. Conclusion: Notably, these data provide evidence for A1ARs playing a key role in the control of both the activation of resident glia and the de novo proliferation of microglia and macrophages after experimental stroke in rats.
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19
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Coppi E, Dettori I, Cherchi F, Bulli I, Venturini M, Lana D, Giovannini MG, Pedata F, Pugliese AM. A 2B Adenosine Receptors: When Outsiders May Become an Attractive Target to Treat Brain Ischemia or Demyelination. Int J Mol Sci 2020; 21:E9697. [PMID: 33353217 PMCID: PMC7766015 DOI: 10.3390/ijms21249697] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/16/2020] [Accepted: 12/16/2020] [Indexed: 12/14/2022] Open
Abstract
Adenosine is a signaling molecule, which, by activating its receptors, acts as an important player after cerebral ischemia. Here, we review data in the literature describing A2BR-mediated effects in models of cerebral ischemia obtained in vivo by the occlusion of the middle cerebral artery (MCAo) or in vitro by oxygen-glucose deprivation (OGD) in hippocampal slices. Adenosine plays an apparently contradictory role in this receptor subtype depending on whether it is activated on neuro-glial cells or peripheral blood vessels and/or inflammatory cells after ischemia. Indeed, A2BRs participate in the early glutamate-mediated excitotoxicity responsible for neuronal and synaptic loss in the CA1 hippocampus. On the contrary, later after ischemia, the same receptors have a protective role in tissue damage and functional impairments, reducing inflammatory cell infiltration and neuroinflammation by central and/or peripheral mechanisms. Of note, demyelination following brain ischemia, or autoimmune neuroinflammatory reactions, are also profoundly affected by A2BRs since they are expressed by oligodendroglia where their activation inhibits cell maturation and expression of myelin-related proteins. In conclusion, data in the literature indicate the A2BRs as putative therapeutic targets for the still unmet treatment of stroke or demyelinating diseases.
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Affiliation(s)
- Elisabetta Coppi
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy; (I.D.); (F.C.); (I.B.); (M.V.); (F.P.); (A.M.P.)
| | - Ilaria Dettori
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy; (I.D.); (F.C.); (I.B.); (M.V.); (F.P.); (A.M.P.)
| | - Federica Cherchi
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy; (I.D.); (F.C.); (I.B.); (M.V.); (F.P.); (A.M.P.)
| | - Irene Bulli
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy; (I.D.); (F.C.); (I.B.); (M.V.); (F.P.); (A.M.P.)
| | - Martina Venturini
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy; (I.D.); (F.C.); (I.B.); (M.V.); (F.P.); (A.M.P.)
| | - Daniele Lana
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, 50139 Florence, Italy; (D.L.); (M.G.G.)
| | - Maria Grazia Giovannini
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, 50139 Florence, Italy; (D.L.); (M.G.G.)
| | - Felicita Pedata
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy; (I.D.); (F.C.); (I.B.); (M.V.); (F.P.); (A.M.P.)
| | - Anna Maria Pugliese
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy; (I.D.); (F.C.); (I.B.); (M.V.); (F.P.); (A.M.P.)
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20
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Gomes JI, Farinha-Ferreira M, Rei N, Gonçalves-Ribeiro J, Ribeiro JA, Sebastião AM, Vaz SH. Of adenosine and the blues: The adenosinergic system in the pathophysiology and treatment of major depressive disorder. Pharmacol Res 2020; 163:105363. [PMID: 33285234 DOI: 10.1016/j.phrs.2020.105363] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 11/30/2020] [Accepted: 12/01/2020] [Indexed: 12/28/2022]
Abstract
Major depressive disorder (MDD) is the foremost cause of global disability, being responsible for enormous personal, societal, and economical costs. Importantly, existing pharmacological treatments for MDD are partially or totally ineffective in a large segment of patients. As such, the search for novel antidepressant drug targets, anchored on a clear understanding of the etiological and pathophysiological mechanisms underpinning MDD, becomes of the utmost importance. The adenosinergic system, a highly conserved neuromodulatory system, appears as a promising novel target, given both its regulatory actions over many MDD-affected systems and processes. With this goal in mind, we herein review the evidence concerning the role of adenosine as a potential player in pathophysiology and treatment of MDD, combining data from both human and animal studies. Altogether, evidence supports the assertions that the adenosinergic system is altered in both MDD patients and animal models, and that drugs targeting this system have considerable potential as putative antidepressants. Furthermore, evidence also suggests that modifications in adenosine signaling may have a key role in the effects of several pharmacological and non-pharmacological antidepressant treatments with demonstrated efficacy, such as electroconvulsive shock, sleep deprivation, and deep brain stimulation. Lastly, it becomes clear from the available literature that there is yet much to study regarding the role of the adenosinergic system in the pathophysiology and treatment of MDD, and we suggest several avenues of research that are likely to prove fruitful.
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Affiliation(s)
- Joana I Gomes
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal; Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Miguel Farinha-Ferreira
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal; Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Nádia Rei
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal; Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Joana Gonçalves-Ribeiro
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal; Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Joaquim A Ribeiro
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal; Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Ana M Sebastião
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal; Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - Sandra H Vaz
- Instituto de Farmacologia e Neurociências, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal; Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.
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21
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Kim SW, Davaanyam D, Seol SI, Lee HK, Lee H, Lee JK. Adenosine Triphosphate Accumulated Following Cerebral Ischemia Induces Neutrophil Extracellular Trap Formation. Int J Mol Sci 2020; 21:ijms21207668. [PMID: 33081303 PMCID: PMC7589755 DOI: 10.3390/ijms21207668] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 10/14/2020] [Accepted: 10/14/2020] [Indexed: 11/20/2022] Open
Abstract
In ischemic stroke, neutrophils infiltrate damaged brain tissue immediately following the ischemic insult and aggravate inflammation via various mechanisms which include neutrophil extracellular traps (NETs) formation. In the present study, we showed that adenosine triphosphate (ATP), a DAMP molecule, accumulates in the brain and induces NETosis in brain parenchyma and in circulating neutrophils (PMNs) isolated from a murine model of stroke induced by middle cerebral artery occlusion (MCAO). Expression of peptidylarginine deiminase-4 (PAD4), which induces citrullination of histones H3 (CitH3) and initiates NETosis, was significantly enhanced in brain parenchyma and blood PMNs following MCAO. ATP or BzATP (a prototypic P2X7R agonist) significantly enhanced the inductions of PAD4 and CitH3 in a P2X7R-dependent manner and intracellular Ca2+ influx, PKCα activation, and NADPH oxidase-dependent reactive oxygen species (ROS) production play critical roles in this ATP-P2X7R-mediated NETosis. In our MCAO animal model, NETosis was markedly suppressed by treatment with apyrase, an enzyme hydrolyzing ATP, but enhanced by co-treatment of BzATP, confirming ATP-P2X7R-mediated NETosis. Since ATP not only induced NETosis but was also extruded after NETosis, our results indicate that ATP accumulated in the ischemic brain induces NETosis, mediating a cross-talk linking NETosis with neuronal damage that might aggravate inflammation and brain damage.
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Affiliation(s)
- Seung-Woo Kim
- Department of Anatomy, Inha University School of Medicine, Incheon 22212, Korea; (S.-W.K.); (D.D.); (S.-I.S.); (H.-K.L.); (H.L.)
- Medical Research Center, Inha University School of Medicine, Incheon 22212, Korea
- Department of Biomedical Sciences, Inha University School of Medicine, Incheon 22212, Korea
| | - Dashdulam Davaanyam
- Department of Anatomy, Inha University School of Medicine, Incheon 22212, Korea; (S.-W.K.); (D.D.); (S.-I.S.); (H.-K.L.); (H.L.)
- Medical Research Center, Inha University School of Medicine, Incheon 22212, Korea
| | - Song-I Seol
- Department of Anatomy, Inha University School of Medicine, Incheon 22212, Korea; (S.-W.K.); (D.D.); (S.-I.S.); (H.-K.L.); (H.L.)
- Medical Research Center, Inha University School of Medicine, Incheon 22212, Korea
- Program in Biomedical Science & Engineering, Inha University School of Medicine, Incheon 22212, Korea
| | - Hye-Kyung Lee
- Department of Anatomy, Inha University School of Medicine, Incheon 22212, Korea; (S.-W.K.); (D.D.); (S.-I.S.); (H.-K.L.); (H.L.)
- Medical Research Center, Inha University School of Medicine, Incheon 22212, Korea
| | - Hahnbie Lee
- Department of Anatomy, Inha University School of Medicine, Incheon 22212, Korea; (S.-W.K.); (D.D.); (S.-I.S.); (H.-K.L.); (H.L.)
- Medical Research Center, Inha University School of Medicine, Incheon 22212, Korea
| | - Ja-Kyeong Lee
- Department of Anatomy, Inha University School of Medicine, Incheon 22212, Korea; (S.-W.K.); (D.D.); (S.-I.S.); (H.-K.L.); (H.L.)
- Medical Research Center, Inha University School of Medicine, Incheon 22212, Korea
- Program in Biomedical Science & Engineering, Inha University School of Medicine, Incheon 22212, Korea
- Correspondence: ; Tel.: +82-32-860-9893
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22
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Adenosinergic System Involvement in Ischemic Stroke Patients' Lymphocytes. Cells 2020; 9:cells9051072. [PMID: 32344922 PMCID: PMC7290971 DOI: 10.3390/cells9051072] [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: 04/01/2020] [Revised: 04/20/2020] [Accepted: 04/22/2020] [Indexed: 12/13/2022] Open
Abstract
Adenosine modulates many physiological processes through the interaction with adenosine receptors (ARs) named as A1, A2A, A2B, and A3ARs. During ischemic stroke, adenosine mediates neuroprotective and anti-inflammatory effects through ARs activation. One of the dominant pathways generating extracellular adenosine involves the dephosphorylation of ATP by ecto-nucleotidases CD39 and CD73, which efficiently hydrolyze extracellular ATP to adenosine. The aim of the study is to assess the presence of ARs in lymphocytes from ischemic stroke patients compared to healthy subjects and to analyze changes in CD39 and CD73 expression in CD4+ and CD8+ lymphocytes. Saturation binding experiments revealed that A2AARs affinity and density were significantly increased in ischemic stroke patients whilst no differences were found in A1, A2B, and A3ARs. These results were also confirmed in reverse transcription (RT)-polymerase chain reaction (PCR) assays where A2AAR mRNA levels of ischemic stroke patients were higher than in control subjects. In flow cytometry experiments, the percentage of CD73+ cells was significantly decreased in lymphocytes and in T-lymphocyte subclasses CD4+ and CD8+ obtained from ischemic stroke patients in comparison with healthy individuals. These data corroborate the importance of the adenosinergic system in ischemic stroke and could open the way to more targeted therapeutic approaches and biomarker development for ischemic stroke.
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23
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Pereira-Figueiredo D, Brito R, Araújo DSM, Nascimento AA, Lyra ESB, Cheibub AMSS, Pereira Netto AD, Ventura ALM, Paes-de-Carvalho R, Calaza KC. Caffeine exposure ameliorates acute ischemic cell death in avian developing retina. Purinergic Signal 2020; 16:41-59. [PMID: 32078115 PMCID: PMC7166236 DOI: 10.1007/s11302-020-09687-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 01/15/2020] [Indexed: 12/20/2022] Open
Abstract
In infants, the main cause of blindness is retinopathy of prematurity that stems in a hypoxic-ischemic condition. Caffeine is a psychoactive compound that at low to moderate concentrations, selectively inhibits adenosine A1 and A2A receptors. Caffeine exerts beneficial effects in central nervous system of adult animal models and humans, whereas it seems to have malefic effect on the developing tissue. We observed that 48-h exposure (during synaptogenesis) to a moderate dose of caffeine (30 mg/kg of egg) activated pro-survival signaling pathways, including ERK, CREB, and Akt phosphorylation, alongside BDNF production, and reduced retinal cell death promoted by oxygen glucose deprivation in the chick retina. Blockade of TrkB receptors and inhibition of CREB prevented caffeine protection effect. Similar signaling pathways were described in previously reported data concerning chemical preconditioning mechanism triggered by NMDA receptors activation, with low concentrations of agonist. In agreement to these data, caffeine increased NMDA receptor activity. Caffeine decreased the levels of the chloride co-transporter KCC2 and delayed the developmental shift on GABAA receptor response from depolarizing to hyperpolarizing. These results suggest that the caffeine-induced delaying in depolarizing effect of GABA could be facilitating NMDA receptor activity. DPCPX, an A1 adenosine receptor antagonist, but not A2A receptor inhibitor, mimicked the effect of caffeine, suggesting that the effect of caffeine occurs through A1 receptor blockade. In summary, an in vivo caffeine exposure could increase the resistance of the retina to ischemia-induced cell death, by triggering survival pathways involving CREB phosphorylation and BDNF production/TrkB activation.
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Affiliation(s)
- D. Pereira-Figueiredo
- Neurobiology of the Retina Laboratory, Fluminense Federal University, Niterói, RJ Brazil
- Laboratory of Neurochemistry, Department of Neurobiology and Program of Neurosciences, Fluminense Federal University, Niterói, RJ Brazil
| | - R. Brito
- Cellular Signaling and Metabolic Modulation Laboratory, Cellular and Molecular Biology Department, Institute of Biology, Fluminense Federal University, Niterói, RJ Brazil
| | - D. S. M. Araújo
- Neurobiology of the Retina Laboratory, Fluminense Federal University, Niterói, RJ Brazil
- Department of Health Sciences, Section of Clinical Pharmacology and Oncology, University of Florence, Florence, Italy
| | - A. A. Nascimento
- Neurobiology of the Retina Laboratory, Fluminense Federal University, Niterói, RJ Brazil
- Laboratory of Neurochemistry, Department of Neurobiology and Program of Neurosciences, Fluminense Federal University, Niterói, RJ Brazil
| | - E. S. B. Lyra
- Fundamental and Applied Analytical Chemistry Laboratory (LAQAFA), Department of Analytical Chemistry, Chemistry Institute, Fluminense Federal University, Niterói, RJ Brazil
| | - A. M. S. S. Cheibub
- Fundamental and Applied Analytical Chemistry Laboratory (LAQAFA), Department of Analytical Chemistry, Chemistry Institute, Fluminense Federal University, Niterói, RJ Brazil
| | - A. D. Pereira Netto
- Fundamental and Applied Analytical Chemistry Laboratory (LAQAFA), Department of Analytical Chemistry, Chemistry Institute, Fluminense Federal University, Niterói, RJ Brazil
| | - A. L. M. Ventura
- Laboratory of Neurochemistry, Department of Neurobiology and Program of Neurosciences, Fluminense Federal University, Niterói, RJ Brazil
- Neurobiology Department, Biology Institute of Fluminense Federal University, Niteroi, Rio de Janeiro Brazil
| | - R. Paes-de-Carvalho
- Laboratory of Cellular Neurobiology, Fluminense Federal University, Niterói, RJ Brazil
- Laboratory of Neurochemistry, Department of Neurobiology and Program of Neurosciences, Fluminense Federal University, Niterói, RJ Brazil
- Neurobiology Department, Biology Institute of Fluminense Federal University, Niteroi, Rio de Janeiro Brazil
| | - K. C. Calaza
- Neurobiology of the Retina Laboratory, Fluminense Federal University, Niterói, RJ Brazil
- Laboratory of Neurochemistry, Department of Neurobiology and Program of Neurosciences, Fluminense Federal University, Niterói, RJ Brazil
- Neurobiology Department, Biology Institute of Fluminense Federal University, Niteroi, Rio de Janeiro Brazil
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24
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Meng F, Guo Z, Hu Y, Mai W, Zhang Z, Zhang B, Ge Q, Lou H, Guo F, Chen J, Duan S, Gao Z. CD73-derived adenosine controls inflammation and neurodegeneration by modulating dopamine signalling. Brain 2020; 142:700-718. [PMID: 30689733 DOI: 10.1093/brain/awy351] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 11/09/2018] [Accepted: 11/22/2018] [Indexed: 12/21/2022] Open
Abstract
Ectonucleotidase-mediated ATP catabolism provides a powerful mechanism to control the levels of extracellular adenosine. While increased adenosine A2A receptor (A2AR) signaling has been well-documented in both Parkinson's disease models and patients, the source of this enhanced adenosine signalling remains unclear. Here, we show that the ecto-5'-nucleotidase (CD73)-mediated adenosine formation provides an important input to activate A2AR, and upregulated CD73 and A2AR in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease models coordinatively contribute to the elevated adenosine signalling. Importantly, we demonstrate that CD73-derived adenosine-A2AR signalling modulates microglial immunoresponses and morphological dynamics. CD73 inactivation significantly attenuated lipopolysaccharide-induced pro-inflammatory responses in microglia, but enhanced microglia process extension, movement and morphological transformation in the laser injury and acute MPTP-induced Parkinson's disease models. Limiting CD73-derived adenosine substantially suppressed microglia-mediated neuroinflammation and improved the viability of dopaminergic neurons and motor behaviours in Parkinson's disease models. Moreover, CD73 inactivation suppressed A2AR induction and A2AR-mediated pro-inflammatory responses, whereas replenishment of adenosine analogues restored these effects, suggesting that CD73 produces a self-regulating feed-forward adenosine formation to activate A2AR and promote neuroinflammation. We further provide the first evidence that A2A enhanced inflammation by antagonizing dopamine-mediated anti-inflammation, suggesting that the homeostatic balance between adenosine and dopamine signalling is key to microglia immunoresponses. Our study thus reveals a novel role for CD73-mediated nucleotide metabolism in regulating neuroinflammation and provides the proof-of-principle that targeting nucleotide metabolic pathways to limit adenosine production and neuroinflammation in Parkinson's disease might be a promising therapeutic strategy.
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Affiliation(s)
- Fan Meng
- Department of Neurobiology and Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhige Guo
- Department of Neurobiology and Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Yaling Hu
- Department of Neurobiology and Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Weihao Mai
- Department of Neurobiology and Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhenjie Zhang
- Department of Neurobiology and Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Bin Zhang
- Department of Neurobiology and Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Qianqian Ge
- Department of Neurobiology and Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Huifang Lou
- Department of Neurobiology and Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Fang Guo
- Department of Neurobiology and Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Jiangfan Chen
- Molecular Neuropharmacology Laboratory and State Key Laboratory of Optometry, Ophthalmology and Vision Science, School of Optometry and Ophthalmology, Wenzhou, Zhejiang, China
| | - Shumin Duan
- Department of Neurobiology and Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Zhihua Gao
- Department of Neurobiology and Second Affiliated Hospital, NHC and CAMS Key Laboratory of Medical Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
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25
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Ceruti S, Abbracchio MP. Adenosine Signaling in Glioma Cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1202:13-33. [PMID: 32034707 DOI: 10.1007/978-3-030-30651-9_2] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Purines and pyrimidines are fundamental signaling molecules in controlling the survival and proliferation of astrocytes, as well as in mediating cell-to-cell communication between glial cells and neurons in the healthy brain. The malignant transformation of astrocytes towards progressively more aggressive brain tumours (from astrocytoma to anaplastic glioblastoma) leads to modifications in both the survival and cell death pathways which overall confer a growth advantage to malignant cells and resistance to many cytotoxic stimuli. It has been demonstrated, however, that, in astrocytomas, several purinergic (in particular adenosinergic) pathways controlling cell survival and death are still effective and, in some cases, even enhanced, providing invaluable targets for purine-based chemotherapy, that still represents an appropriate pharmacological approach to brain tumours. In this chapter, the current knowledge on both receptor-mediated and receptor-independent adenosine pathways in astrocytomas will be reviewed, with a particular emphasis on the most promising targets which could be translated from in vitro studies to in vivo pharmacology. Additionally, we have included new original data from our laboratory demonstrating a key involvement of MAP kinases in the cytostastic and cytotoxic effects exerted by an adenosine analogue, 2-CdA, which with the name of Cladribine is already clinically utilized in haematological malignancies. Here we show that 2-CdA can activate multiple intracellular pathways leading to cell cycle block and cell death by apoptosis of a human astrocytoma cell line that bears several pro-survival genetic mutations. Although in vivo data are still lacking, our results suggest that adenosine analogues could therefore be exploited to overcome resistance to chemotherapy of brain tumours.
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Affiliation(s)
- Stefania Ceruti
- Laboratory of Molecular and Cellular Pharmacology of Purinergic Transmission, Department of Pharmacological Sciences, University of Milan - Università degli Studi di Milano, Milan, Italy.
| | - Maria P Abbracchio
- Laboratory of Molecular and Cellular Pharmacology of Purinergic Transmission, Department of Pharmacological Sciences, University of Milan - Università degli Studi di Milano, Milan, Italy
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26
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Mild hypothermia protects synaptic transmission from experimental ischemia through reduction in the function of nucleoside transporters in the mouse hippocampus. Neuropharmacology 2019; 163:107853. [PMID: 31734385 DOI: 10.1016/j.neuropharm.2019.107853] [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: 09/10/2019] [Revised: 10/28/2019] [Accepted: 11/12/2019] [Indexed: 12/24/2022]
Abstract
Ischemia, a severe metabolic stress, increases adenosine levels and causes the suppression of synaptic transmission through adenosine A1 receptors. Although temperature also regulates extracellular adenosine levels, the effect of temperature on ischemia-induced activation of adenosine receptors is not yet fully understood. Here we examined the role of adenosine A1 receptors in mild hypothermia-mediated neuroprotection during the acute phase of ischemia. Severe ischemia-induced neurosynaptic impairment was reproduced by oxygen-glucose deprivation at normothermia (36 °C) and assessed with extracellular recordings or whole-cell patch clamp recordings in acute hippocampal slices in mice. Mild hypothermia (32 °C) induced the protection of synaptic transmission by activating adenosine A1 receptors. Stricter hypothermia (28 °C) caused additional neuroprotective effects by extending the onset time to anoxic depolarization; however, this effect was not associated with adenosine A1 receptors. The response of exogenous adenosine-induced inhibition of hippocampal synaptic transmission was increased by lowering the temperature to 32 °C or 28 °C. Hypothermia also reduced the function of dipryidamole-sensitive nucleoside transporters. These findings suggest that an increased response of adenosine A1 receptors, caused by a reduction in the function of nucleoside transporters, is one mechanism by which therapeutic hypothermia (usually used within the mild range) mediates neurosynaptic protection in the acute phase of stroke.
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27
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Carmo M, Gonçalves FQ, Canas PM, Oses JP, Fernandes FD, Duarte FV, Palmeira CM, Tomé AR, Agostinho P, Andrade GM, Cunha RA. Enhanced ATP release and CD73-mediated adenosine formation sustain adenosine A 2A receptor over-activation in a rat model of Parkinson's disease. Br J Pharmacol 2019; 176:3666-3680. [PMID: 31220343 DOI: 10.1111/bph.14771] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2018] [Revised: 05/01/2019] [Accepted: 06/01/2019] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND AND PURPOSE Parkinson's disease (PD) involves an initial loss of striatal dopamine terminals evolving into degeneration of dopamine neurons in substantia nigra (SN), which can be modelled by 6-hydroxydopamine (6-OHDA) administration. Adenosine A2A receptor blockade attenuates PD features in animal models, but the source of the adenosine causing A2A receptor over-activation is unknown. As ATP is a stress signal, we have tested if extracellular catabolism of adenine nucleotides into adenosine (through ecto-5'-nucleotidase or CD73) leads to A2A receptor over-activation in PD. EXPERIMENTAL APPROACH Effects of blocking CD73 with α,β-methylene ADP (AOPCP) were assayed in 6-OHDA-treated rats and dopamine-differentiated neuroblastoma SH-SY5Y cells. KEY RESULTS 6-OHDA increased ATP release and extracellular conversion into adenosine through CD73 up-regulation in SH-SY5Y cells. Removing extracellular adenosine with adenosine deaminase, blocking CD73 with AOPCP, or blocking A2A receptors with SCH58261 were equi-effective in preventing 6-OHDA-induced damage in SH-SY5Y cells. In vivo striatal exposure to 6-OHDA increased ATP release and extracellular formation of adenosine from adenosine nucleotides and up-regulated CD73 and A2A receptors in striatal synaptosomes. Intracerebroventricular administration of AOPCP phenocopied effects of SCH58261, attenuating 6-OHDA-induced (a) increase of contralateral rotations after apomorphine, (b) reduction of dopamine content in striatum and SN, (c) loss of TH staining in striatum and SN, (d) motor dysfunction in the cylinder test, and (e) short-term memory impairment in the object recognition test. CONCLUSION AND IMPLICATIONS Our data indicate that increased ATP-derived adenosine formation is responsible for A2A receptor over-activation in PD, suggesting CD73 as a new target to manage PD.
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Affiliation(s)
- Marta Carmo
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Department of Physiology and Pharmacology, Federal University of Ceará, Fortaleza, Brazil
| | - Francisco Q Gonçalves
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Paula M Canas
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Jean-Pierre Oses
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Francisco D Fernandes
- Department of Physiology and Pharmacology, Federal University of Ceará, Fortaleza, Brazil
| | - Filipe V Duarte
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Carlos M Palmeira
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Department of Life Sciences, Faculty of Science and Technology, University of Coimbra, Coimbra, Portugal
| | - Angelo R Tomé
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Department of Life Sciences, Faculty of Science and Technology, University of Coimbra, Coimbra, Portugal
| | - Paula Agostinho
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,FMUC-Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Geanne M Andrade
- Department of Physiology and Pharmacology, Federal University of Ceará, Fortaleza, Brazil
| | - Rodrigo A Cunha
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,FMUC-Faculty of Medicine, University of Coimbra, Coimbra, Portugal
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28
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Fusco I, Cherchi F, Catarzi D, Colotta V, Varano F, Pedata F, Pugliese AM, Coppi E. Functional characterization of a novel adenosine A 2B receptor agonist on short-term plasticity and synaptic inhibition during oxygen and glucose deprivation in the rat CA1 hippocampus. Brain Res Bull 2019; 151:174-180. [PMID: 31132418 DOI: 10.1016/j.brainresbull.2019.05.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 04/30/2019] [Accepted: 05/02/2019] [Indexed: 12/22/2022]
Abstract
Adenosine is an endogenous neuromodulator exerting its biological functions via four receptor subtypes, A1, A2A, A2B, and A3. A2B receptors (A2BRs) are expressed at hippocampal level where they are known to inhibit paired pulse facilitation (PPF), whose reduction reflects an increase in presynaptic glutamate release. The effect of A2BRs on PPF is known to be sensitive not only to A2BR blockade but also to the A1R antagonist DPCPX, indicating that it involves A1R activation. In this study we provide the first functional characterization of the newly synthesized non-nucleoside like A2BR agonist P453, belonging to the amino-3,5-dicyanopyridine series. By extracellular electrophysiological recordings, we demonstrated that P453 mimicked the effect of the prototypical A2BR agonist BAY60-6583 in decreasing PPF at Schaffer collateral-CA1 synapses in rat acute hippocampal slices. This effect was prevented by two different A2BR antagonists, PSB603 and MRS1754, and by the A1R antagonist DPCPX. We also investigated the functional role of A2BR during a 2 min of oxygen and glucose deprivation (OGD) insult, known to produce a reversible fEPSP inhibition due to adenosine A1R activation. We found that P453 and BAY60-6583 significantly delayed the onset of fEPSP reduction induced by OGD and the effect was blocked by PSB603. We conclude that P453 is a functional A2BR agonist whose activation decreases PPF by increasing glutamate release at presynaptic terminals and delays A1R-mediated fEPSP inhibition during a 2-minute OGD insult.
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Affiliation(s)
- Irene Fusco
- Department of Neuroscience, Psychology, Drug Research and Child Health, NEUROFARBA, Section of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Federica Cherchi
- Department of Neuroscience, Psychology, Drug Research and Child Health, NEUROFARBA, Section of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Daniela Catarzi
- Section of Pharmaceutical and Nutraceutical Sciences, University of Florence, Florence, Italy
| | - Vittoria Colotta
- Section of Pharmaceutical and Nutraceutical Sciences, University of Florence, Florence, Italy
| | - Flavia Varano
- Section of Pharmaceutical and Nutraceutical Sciences, University of Florence, Florence, Italy
| | - Felicita Pedata
- Department of Neuroscience, Psychology, Drug Research and Child Health, NEUROFARBA, Section of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Anna Maria Pugliese
- Department of Neuroscience, Psychology, Drug Research and Child Health, NEUROFARBA, Section of Pharmacology and Toxicology, University of Florence, Florence, Italy
| | - Elisabetta Coppi
- Department of Neuroscience, Psychology, Drug Research and Child Health, NEUROFARBA, Section of Pharmacology and Toxicology, University of Florence, Florence, Italy.
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29
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Nedeljkovic N. Complex regulation of ecto-5'-nucleotidase/CD73 and A 2AR-mediated adenosine signaling at neurovascular unit: A link between acute and chronic neuroinflammation. Pharmacol Res 2019; 144:99-115. [PMID: 30954629 DOI: 10.1016/j.phrs.2019.04.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 04/01/2019] [Accepted: 04/03/2019] [Indexed: 12/20/2022]
Abstract
The review summarizes available data regarding the complex regulation of CD73 at the neurovascular unit (NVU) during neuroinflammation. Based on available data we propose the biphasic pattern of CD73 regulation at NVU, with an early attenuation and a postponed up-regulation of CD73 activity. Transient attenuation of CD73 activity on leukocyte/vascular endothelium and leukocyte/astrocyte surface, required for the initiation of a neuroinflammatory response, may be effectuated either by catalytic inhibition of CD73 and/or by shedding of the CD73 molecule from the cell surface, while postponed induction of CD73 is effectuated by transcriptional up-regulation of Nt5e and posttranslational modifications. Neuroinflammatory conditions are also associated with significant enhancement and gain-of-function of A2AR-mediated adenosine signaling. However, in contrast to the temporary prevalence of A2AR over A1R signaling during an acute inflammatory response, prolonged induction of A2AR and resulting perpetual CD73/A2AR coupling may be a contributing factors in the transition between acute and chronic neuroinflammation. Thus, pharmacological targeting of the CD73/A2AR axis may attenuate inflammatory response and ameliorate neurological deficits in chronic neuroinflammatory conditions.
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Affiliation(s)
- Nadezda Nedeljkovic
- Department of General Physiology and Biophysics, Faculty of Biology University of Belgrade, Studentski trg 3, Belgrade 11001, Serbia.
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30
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Zhou KQ, Green CR, Bennet L, Gunn AJ, Davidson JO. The Role of Connexin and Pannexin Channels in Perinatal Brain Injury and Inflammation. Front Physiol 2019; 10:141. [PMID: 30873043 PMCID: PMC6400979 DOI: 10.3389/fphys.2019.00141] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 02/07/2019] [Indexed: 12/21/2022] Open
Abstract
Perinatal brain injury remains a major cause of death and life-long disability. Perinatal brain injury is typically associated with hypoxia-ischemia and/or infection/inflammation. Both hypoxia-ischemia and infection trigger an inflammatory response in the brain. The inflammatory response can contribute to brain cell loss and chronic neuroinflammation leading to neurological impairments. It is now well-established that brain injury evolves over time, and shows a striking spread from injured to previously uninjured regions of the brain. There is increasing evidence that this spread is related to opening of connexin hemichannels and pannexin channels, both of which are large conductance membrane channels found in almost all cell types in the brain. Blocking connexin hemichannels within the first 3 h after hypoxia-ischemia has been shown to improve outcomes in term equivalent fetal sheep but it is important to also understand the downstream pathways linking membrane channel opening with the development of injury in order to identify new therapeutic targets. Open membrane channels release adenosine triphosphate (ATP), and other neuroactive molecules, into the extracellular space. ATP has an important physiological role, but has also been reported to act as a damage-associated molecular pattern (DAMP) signal mediated through specific purinergic receptors and so act as a primary signal 1 in the innate immune system inflammasome pathway. More crucially, extracellular ATP is a key inflammasome signal 2 activator, with purinergic receptor binding triggering the assembly of the multi-protein inflammasome complex. The inflammasome pathway and complex formation contribute to activation of inflammatory caspases, and the release of inflammatory cytokines, including interleukin (IL)-1β, tumor necrosis factor (TNF)-α, IL-18, and vascular endothelial growth factor (VEGF). We propose that the NOD-like receptor protein-3 (NLRP3) inflammasome, which has been linked to inflammatory responses in models of ischemic stroke and various inflammatory diseases, may be one mechanism by which connexin hemichannel opening especially mediates perinatal brain injury.
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Affiliation(s)
- Kelly Q Zhou
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Colin R Green
- Department of Ophthalmology, The University of Auckland, Auckland, New Zealand
| | - Laura Bennet
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Alistair J Gunn
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Joanne O Davidson
- Department of Physiology, The University of Auckland, Auckland, New Zealand.,Department of Ophthalmology, The University of Auckland, Auckland, New Zealand
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31
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Ferrari F, Viscardi P, Gorini A, Villa RF. Synaptic ATPases system of rat frontal cerebral cortex during aging. Neurosci Lett 2019; 694:74-79. [DOI: 10.1016/j.neulet.2018.11.028] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Revised: 11/01/2018] [Accepted: 11/19/2018] [Indexed: 01/28/2023]
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32
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Hackett TA. Adenosine A 1 Receptor mRNA Expression by Neurons and Glia in the Auditory Forebrain. Anat Rec (Hoboken) 2018; 301:1882-1905. [PMID: 30315630 PMCID: PMC6282551 DOI: 10.1002/ar.23907] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 12/05/2017] [Accepted: 01/10/2018] [Indexed: 12/30/2022]
Abstract
In the brain, purines such as ATP and adenosine can function as neurotransmitters and co‐transmitters, or serve as signals in neuron–glial interactions. In thalamocortical (TC) projections to sensory cortex, adenosine functions as a negative regulator of glutamate release via activation of the presynaptic adenosine A1 receptor (A1R). In the auditory forebrain, restriction of A1R‐adenosine signaling in medial geniculate (MG) neurons is sufficient to extend LTP, LTD, and tonotopic map plasticity in adult mice for months beyond the critical period. Interfering with adenosine signaling in primary auditory cortex (A1) does not contribute to these forms of plasticity, suggesting regional differences in the roles of A1R‐mediated adenosine signaling in the forebrain. To advance understanding of the circuitry, in situ hybridization was used to localize neuronal and glial cell types in the auditory forebrain that express A1R transcripts (Adora1), based on co‐expression with cell‐specific markers for neuronal and glial subtypes. In A1, Adora1 transcripts were concentrated in L3/4 and L6 of glutamatergic neurons. Subpopulations of GABAergic neurons, astrocytes, oligodendrocytes, and microglia expressed lower levels of Adora1. In MG, Adora1 was expressed by glutamatergic neurons in all divisions, and subpopulations of all glial classes. The collective findings imply that A1R‐mediated signaling broadly extends to all subdivisions of auditory cortex and MG. Selective expression by neuronal and glial subpopulations suggests that experimental manipulations of A1R‐adenosine signaling could impact several cell types, depending on their location. Strategies to target Adora1 in specific cell types can be developed from the data generated here. Anat Rec, 301:1882–1905, 2018. © 2018 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.
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Affiliation(s)
- Troy A Hackett
- Department of Hearing and Speech Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA.,Department of Psychology, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennessee, USA.,Vanderbilt Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, Tennessee, USA
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33
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van der Mierden S, Savelyev SA, IntHout J, de Vries RBM, Leenaars CHC. Intracerebral microdialysis of adenosine and adenosine monophosphate - a systematic review and meta-regression analysis of baseline concentrations. J Neurochem 2018; 147:58-70. [PMID: 30025168 PMCID: PMC6220825 DOI: 10.1111/jnc.14552] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 07/02/2018] [Accepted: 07/12/2018] [Indexed: 01/18/2023]
Abstract
Microdialysis is a method to study the extracellular space in vivo, based on the principle of diffusion. It can be used to measure various small molecules including the neuroregulator adenosine. Baseline levels of the compounds measured with microdialysis vary over studies. We systematically reviewed the literature to investigate the full range of reported baseline concentrations of adenosine and adenosine monophosphate in microdialysates. We performed a meta‐regression analysis to study the influence of flow rate, probe membrane surface area, species, brain area and anaesthesia versus freely behaving, on the adenosine concentration. Baseline adenosine concentrations in microdialysates ranged from 0.8 to 2100 nM. There was limited evidence on baseline adenosine monophosphate concentrations in microdialysates. Across studies, we found effects of flow rate and anaesthesia versus freely behaving on dialysate adenosine concentrations (p ≤ 0.001), but not of probe membrane surface, species, or brain area (p ≥ 0.14). With increasing flow rate, adenosine concentrations decreased. With anaesthesia, adenosine concentrations increased. The effect of other predictor variables on baseline adenosine concentrations, for example, post‐surgical recovery time, could not be analysed because of a lack of reported data. This study shows that meta‐regression can be used as an alternative to new animal experiments to answer research questions in the field of neurochemistry. However, current levels of reporting of primary studies are insufficient to reach the full potential of this approach; 63 out of 133 studies could not be included in the analysis because of insufficient reporting, and several potentially relevant factors had to be excluded from the analyses. The level of reporting of experimental detail needs to improve. ![]()
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Affiliation(s)
- Stevie van der Mierden
- SYRCLE, Department for Health Evidence, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.,Institute for Laboratory Animal Science, Hannover Medical School, Hannover, Germany
| | - Sergey A Savelyev
- Medical Biological Research & Development Centre 'Cytomed', St.-Petersburg, Russia
| | - Joanna IntHout
- Department for Health Evidence, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Rob B M de Vries
- SYRCLE, Department for Health Evidence, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Cathalijn H C Leenaars
- SYRCLE, Department for Health Evidence, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.,Institute for Laboratory Animal Science, Hannover Medical School, Hannover, Germany.,Department of Animals in Science and Society - Human-Animal Relationship, Utrecht University, Utrecht, The Netherlands
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34
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Pastor-Anglada M, Pérez-Torras S. Who Is Who in Adenosine Transport. Front Pharmacol 2018; 9:627. [PMID: 29962948 PMCID: PMC6010718 DOI: 10.3389/fphar.2018.00627] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 05/24/2018] [Indexed: 12/13/2022] Open
Abstract
Extracellular adenosine concentrations are regulated by a panel of membrane transporters which, in most cases, mediate its uptake into cells. Adenosine transporters belong to two gene families encoding Equilibrative and Concentrative Nucleoside Transporter proteins (ENTs and CNTs, respectively). The lack of appropriate pharmacological tools targeting every transporter subtype has introduced some bias on the current knowledge of the role of these transporters in modulating adenosine levels. In this regard, ENT1, for which pharmacology is relatively well-developed, has often been identified as a major player in purinergic signaling. Nevertheless, other transporters such as CNT2 and CNT3 can also contribute to purinergic modulation based on their high affinity for adenosine and concentrative capacity. Moreover, both transporter proteins have also been shown to be under purinergic regulation via P1 receptors in different cell types, which further supports its relevance in purinergic signaling. Thus, several transporter proteins regulate extracellular adenosine levels. Moreover, CNT and ENT proteins are differentially expressed in tissues but also in particular cell types. Accordingly, transporter-mediated fine tuning of adenosine levels is cell and tissue specific. Future developments focusing on CNT pharmacology are needed to unveil transporter subtype-specific events.
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Affiliation(s)
- Marçal Pastor-Anglada
- Molecular Pharmacology and Experimental Therapeutics, Department of Biochemistry and Molecular Biomedicine, Institute of Biomedicine, University of Barcelona, Barcelona, Spain
- Oncology Program, National Biomedical Research Institute on Liver and Gastrointestinal Diseases – CIBER ehd, Institut de Recerca Sant Joan de Déu, Barcelona, Spain
| | - Sandra Pérez-Torras
- Molecular Pharmacology and Experimental Therapeutics, Department of Biochemistry and Molecular Biomedicine, Institute of Biomedicine, University of Barcelona, Barcelona, Spain
- Oncology Program, National Biomedical Research Institute on Liver and Gastrointestinal Diseases – CIBER ehd, Institut de Recerca Sant Joan de Déu, Barcelona, Spain
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35
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Ganesana M, Venton BJ. Early changes in transient adenosine during cerebral ischemia and reperfusion injury. PLoS One 2018; 13:e0196932. [PMID: 29799858 PMCID: PMC5969733 DOI: 10.1371/journal.pone.0196932] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Accepted: 04/23/2018] [Indexed: 12/20/2022] Open
Abstract
Adenosine is an important neuromodulator in the central nervous system, and tissue adenosine levels increase during ischemic events, attenuating excitotoxic neuronal injury. Recently, our lab developed an electrochemical fast-scan cyclic voltammetry (FSCV) method that identified rapid, spontaneous changes in adenosine concentrations that last only about 3 seconds. Here, we investigated the effects of cerebral ischemia and reperfusion on the concentration and frequency of transient adenosine release in the caudate-putamen. In anesthetized rats, data were collected for four hours: two hours of normoxia, 30 min of cerebral ischemia induced by bilateral common carotid artery occlusion, and 90 min of reperfusion. Transient adenosine release was increased during the cerebral ischemia period and remained elevated during reperfusion. The total number of adenosine transients increased by 52% during cerebral ischemia and reperfusion compared to normoxia. The concentration of adenosine per event did not increase but the cumulative adenosine concentration during cerebral ischemia and reperfusion increased by 53% because of the higher frequency of events. Further, we evaluated the role of A2A antagonist, SCH442416, a putative neuroprotective agent to affect adenosine transients. SCH442416 significantly decreased the transient frequency during cerebral ischemia-reperfusion by 27% and the cumulative concentration by 31%. Our results demonstrate that this mode of rapid adenosine release increases during early cerebral ischemia-reperfusion injury. Rapid adenosine release could provide fast, local neuromodulation and neuroprotection during cerebral ischemia.
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Affiliation(s)
| | - B Jill Venton
- Department of Chemistry and Neuroscience Graduate Program, University of Virginia, Charlottesville, VA, United States of America
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36
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Stefani J, Tschesnokowa O, Parrilla M, Robaye B, Boeynaems JM, Acker-Palmer A, Zimmermann H, Gampe K. Disruption of the Microglial ADP Receptor P2Y 13 Enhances Adult Hippocampal Neurogenesis. Front Cell Neurosci 2018; 12:134. [PMID: 29867367 PMCID: PMC5966569 DOI: 10.3389/fncel.2018.00134] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 04/30/2018] [Indexed: 12/20/2022] Open
Abstract
In mammalian species, including humans, the hippocampal dentate gyrus (DG) is a primary region of adult neurogenesis. Aberrant adult hippocampal neurogenesis is associated with neurological pathologies. Understanding the cellular mechanisms controlling adult hippocampal neurogenesis is expected to open new therapeutic strategies for mental disorders. Microglia is intimately associated with neural progenitor cells in the hippocampal DG and has been implicated, under varying experimental conditions, in the control of the proliferation, differentiation and survival of neural precursor cells. But the underlying mechanisms remain poorly defined. Using fluorescent in situ hybridization we show that microglia in brain express the ADP-activated P2Y13 receptor under basal conditions and that P2ry13 mRNA is absent from neurons, astrocytes, and neural progenitor cells. Disrupting P2ry13 decreases structural complexity of microglia in the hippocampal subgranular zone (SGZ). But it increases progenitor cell proliferation and new neuron formation. Our data suggest that P2Y13 receptor-activated microglia constitutively attenuate hippocampal neurogenesis. This identifies a signaling pathway whereby microglia, via a nucleotide-mediated mechanism, contribute to the homeostatic control of adult hippocampal neurogenesis. Selective P2Y13R antagonists could boost neurogenesis in pathological conditions associated with impaired hippocampal neurogenesis.
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Affiliation(s)
- Jennifer Stefani
- Institute of Cell Biology and Neuroscience and Buchmann Institute for Molecular Life Sciences, Goethe-University, Frankfurt am Main, Germany
| | - Olga Tschesnokowa
- Institute of Cell Biology and Neuroscience and Buchmann Institute for Molecular Life Sciences, Goethe-University, Frankfurt am Main, Germany
| | - Marta Parrilla
- Institute of Cell Biology and Neuroscience and Buchmann Institute for Molecular Life Sciences, Goethe-University, Frankfurt am Main, Germany.,Max-Planck-Institute for Brain Research, Frankfurt am Main, Germany
| | - Bernard Robaye
- Institute of Interdisciplinary Research, School of Medicine, Université Libre de Bruxelles, Bruxelles, Belgium
| | - Jean-Marie Boeynaems
- Institute of Interdisciplinary Research, School of Medicine, Université Libre de Bruxelles, Bruxelles, Belgium
| | - Amparo Acker-Palmer
- Institute of Cell Biology and Neuroscience and Buchmann Institute for Molecular Life Sciences, Goethe-University, Frankfurt am Main, Germany.,Max-Planck-Institute for Brain Research, Frankfurt am Main, Germany.,Focus Program Translational Neurosciences (FTN), University of Mainz, Mainz, Germany
| | - Herbert Zimmermann
- Institute of Cell Biology and Neuroscience and Buchmann Institute for Molecular Life Sciences, Goethe-University, Frankfurt am Main, Germany
| | - Kristine Gampe
- Institute of Cell Biology and Neuroscience and Buchmann Institute for Molecular Life Sciences, Goethe-University, Frankfurt am Main, Germany
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37
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Martín A, Domercq M, Matute C. Inflammation in stroke: the role of cholinergic, purinergic and glutamatergic signaling. Ther Adv Neurol Disord 2018; 11:1756286418774267. [PMID: 29774059 PMCID: PMC5949933 DOI: 10.1177/1756286418774267] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 03/26/2018] [Indexed: 12/27/2022] Open
Abstract
The inflammatory response is a major factor in stroke pathophysiology and contributes to secondary neuronal damage in both acute and chronic stages of the ischemic injury. Recent work in experimental cerebral ischemia has demonstrated the involvement of neurotransmitter signaling in the modulation of neuroinflammation. The present review discusses recent findings on the therapeutic potential and diagnostic perspectives of cholinergic, purinergic and glutamatergic receptors and transporters in experimental stroke. It provides evidence of the role of neurotransmission signaling as a promising inflammatory biomarker in stroke. Finally, recent molecular imaging studies using positron emission tomography of cholinergic receptors and glutamatergic transporters are outlined along with their potential as novel anti-inflammatory therapy to reduce the outcome of cerebral ischemia.
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Affiliation(s)
- Abraham Martín
- Experimental Molecular Imaging, Molecular Imaging Unit, CIC biomaGUNE, Pº Miramon 182, San Sebastian, Spain
| | - María Domercq
- Department of Neurosciences, University of the Basque Country, Barrio Sarriena s/n, Leioa, Spain Achucarro Basque Center for Neuroscience-UPV/EHU, Zamudio, Spain Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Leioa, Spain
| | - Carlos Matute
- Department of Neurosciences, University of the Basque Country, Barrio Sarriena s/n, Leioa, Spain Achucarro Basque Center for Neuroscience-UPV/EHU, Zamudio, Spain Instituto de Salud Carlos III, Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Leioa, Spain
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38
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Dvoriantchikova G, Pronin A, Kurtenbach S, Toychiev A, Chou TH, Yee CW, Prindeville B, Tayou J, Porciatti V, Sagdullaev BT, Slepak VZ, Shestopalov VI. Pannexin 1 sustains the electrophysiological responsiveness of retinal ganglion cells. Sci Rep 2018; 8:5797. [PMID: 29643381 PMCID: PMC5895610 DOI: 10.1038/s41598-018-23894-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 03/20/2018] [Indexed: 12/16/2022] Open
Abstract
Pannexin 1 (Panx1) forms ATP-permeable membrane channels that play a key role in purinergic signaling in the nervous system in both normal and pathological conditions. In the retina, particularly high levels of Panx1 are found in retinal ganglion cells (RGCs), but the normal physiological function in these cells remains unclear. In this study, we used patch clamp recordings in the intact inner retina to show that evoked currents characteristic of Panx1 channel activity were detected only in RGCs, particularly in the OFF-type cells. The analysis of pattern electroretinogram (PERG) recordings indicated that Panx1 contributes to the electrical output of the retina. Consistently, PERG amplitudes were significantly impaired in the eyes with targeted ablation of the Panx1 gene in RGCs. Under ocular hypertension and ischemic conditions, however, high Panx1 activity permeated cell membranes and facilitated the selective loss of RGCs or stably transfected Neuro2A cells. Our results show that high expression of the Panx1 channel in RGCs is essential for visual function in the inner retina but makes these cells highly sensitive to mechanical and ischemic stresses. These findings are relevant to the pathophysiology of retinal disorders induced by increased intraocular pressure, such as glaucoma.
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Affiliation(s)
- Galina Dvoriantchikova
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, 900 NW 10 Ave., Miami, FL, 33136, USA
| | - Alexey Pronin
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, 1600 NW 10th Ave., Miami, FL, 33136, USA
| | - Sarah Kurtenbach
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, 900 NW 10 Ave., Miami, FL, 33136, USA
| | - Abduqodir Toychiev
- Department of Ophthalmology, Weill Cornell Medical College, 156 William St., New York, NY, 10038, USA
| | - Tsung-Han Chou
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, 900 NW 10 Ave., Miami, FL, 33136, USA
| | - Christopher W Yee
- Winifred Masterson Burke Medical Research Institute, New York, 785 Mamaroneck Ave., White Plains, NY, 10605, USA
| | - Breanne Prindeville
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, 900 NW 10 Ave., Miami, FL, 33136, USA
| | - Junior Tayou
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, 1600 NW 10th Ave., Miami, FL, 33136, USA
| | - Vittorio Porciatti
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, 900 NW 10 Ave., Miami, FL, 33136, USA
| | - Botir T Sagdullaev
- Department of Ophthalmology, Weill Cornell Medical College, 156 William St., New York, NY, 10038, USA
- Winifred Masterson Burke Medical Research Institute, New York, 785 Mamaroneck Ave., White Plains, NY, 10605, USA
| | - Vladlen Z Slepak
- Department of Molecular and Cellular Pharmacology, University of Miami Miller School of Medicine, 1600 NW 10th Ave., Miami, FL, 33136, USA
| | - Valery I Shestopalov
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, 900 NW 10 Ave., Miami, FL, 33136, USA.
- Department of Cell Biology, University of Miami Miller School of Medicine, 1600 NW 10th Ave., Miami, FL, 33136, USA.
- Vavilov Institute for General Genetics, Gubkina Str. 3, Russian Academy of Sciences, Moscow, Russia.
- Kharkevich Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow, Russia.
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Madry C, Arancibia-Cárcamo IL, Kyrargyri V, Chan VTT, Hamilton NB, Attwell D. Effects of the ecto-ATPase apyrase on microglial ramification and surveillance reflect cell depolarization, not ATP depletion. Proc Natl Acad Sci U S A 2018; 115:E1608-E1617. [PMID: 29382767 PMCID: PMC5816168 DOI: 10.1073/pnas.1715354115] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Microglia, the brain's innate immune cells, have highly motile processes which constantly survey the brain to detect infection, remove dying cells, and prune synapses during brain development. ATP released by tissue damage is known to attract microglial processes, but it is controversial whether an ambient level of ATP is needed to promote constant microglial surveillance in the normal brain. Applying the ATPase apyrase, an enzyme which hydrolyzes ATP and ADP, reduces microglial process ramification and surveillance, suggesting that ambient ATP/ADP maintains microglial surveillance. However, attempting to raise the level of ATP/ADP by blocking the endogenous ecto-ATPase (termed NTPDase1/CD39), which also hydrolyzes ATP/ADP, does not affect the cells' ramification or surveillance, nor their membrane currents, which respond to even small rises of extracellular [ATP] or [ADP] with the activation of K+ channels. This indicates a lack of detectable ambient ATP/ADP and ecto-ATPase activity, contradicting the results with apyrase. We resolve this contradiction by demonstrating that contamination of commercially available apyrase by a high K+ concentration reduces ramification and surveillance by depolarizing microglia. Exposure to the same K+ concentration (without apyrase added) reduced ramification and surveillance as with apyrase. Dialysis of apyrase to remove K+ retained its ATP-hydrolyzing activity but abolished the microglial depolarization and decrease of ramification produced by the undialyzed enzyme. Thus, applying apyrase affects microglia by an action independent of ATP, and no ambient purinergic signaling is required to maintain microglial ramification and surveillance. These results also have implications for hundreds of prior studies that employed apyrase to hydrolyze ATP/ADP.
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Affiliation(s)
- Christian Madry
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, United Kingdom;
- Institute of Neurophysiology, Charité Universitätsmedizin, 10117 Berlin, Germany
| | - I Lorena Arancibia-Cárcamo
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, United Kingdom
| | - Vasiliki Kyrargyri
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, United Kingdom
| | - Victor T T Chan
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, United Kingdom
| | - Nicola B Hamilton
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, United Kingdom;
- Wolfson Centre for Age-Related Diseases, King's College London, London SE1 1UL, United Kingdom
| | - David Attwell
- Department of Neuroscience, Physiology and Pharmacology, University College London, London WC1E 6BT, United Kingdom;
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40
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Rodrigues-Neves AC, Aires ID, Vindeirinho J, Boia R, Madeira MH, Gonçalves FQ, Cunha RA, Santos PF, Ambrósio AF, Santiago AR. Elevated Pressure Changes the Purinergic System of Microglial Cells. Front Pharmacol 2018; 9:16. [PMID: 29416510 PMCID: PMC5787565 DOI: 10.3389/fphar.2018.00016] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 01/05/2018] [Indexed: 12/20/2022] Open
Abstract
Glaucoma is the second cause of blindness worldwide and is characterized by the degeneration of retinal ganglion cells (RGCs) and optic nerve atrophy. Increased microglia reactivity is an early event in glaucoma that may precede the loss of RGCs, suggesting that microglia and neuroinflammation are involved in the pathophysiology of this disease. Although global changes of the purinergic system have been reported in experimental and human glaucoma, it is not known if this is due to alterations of the purinergic system of microglial cells, the resident immune cells of the central nervous system. We now studied if elevated hydrostatic pressure (EHP), mimicking ocular hypertension, changed the extracellular levels of ATP and adenosine and the expression, density and activity of enzymes, transporters and receptors defining the purinergic system. The exposure of the murine microglial BV-2 cell line to EHP increased the extracellular levels of ATP and adenosine, increased the density of ecto-nucleoside triphosphate diphosphohydrolase 1 (E-NTPDase1, CD39) and decreased the density of the equilibrative nucleotide transporter 2 as well as the activity of adenosine deaminase. The expression of adenosine A1 receptor also decreased, but the adenosine A3 receptor was not affected. Notably, ATP and adenosine selectively control migration rather than phagocytosis, both bolstered by EHP. The results show that the purinergic system is altered in microglia in conditions of elevated pressure. Understanding the impact of elevated pressure on the purinergic system will help to unravel the mechanisms underlying inflammation and neurodegeneration associated with glaucoma.
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Affiliation(s)
- Ana C Rodrigues-Neves
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI Consortium, University of Coimbra, Coimbra, Portugal
| | - Inês D Aires
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI Consortium, University of Coimbra, Coimbra, Portugal
| | - Joana Vindeirinho
- CNC.IBILI Consortium, University of Coimbra, Coimbra, Portugal.,Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Raquel Boia
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI Consortium, University of Coimbra, Coimbra, Portugal
| | - Maria H Madeira
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI Consortium, University of Coimbra, Coimbra, Portugal
| | - Francisco Q Gonçalves
- CNC.IBILI Consortium, University of Coimbra, Coimbra, Portugal.,Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Rodrigo A Cunha
- CNC.IBILI Consortium, University of Coimbra, Coimbra, Portugal.,Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Paulo F Santos
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI Consortium, University of Coimbra, Coimbra, Portugal.,Department of Life Sciences, Faculty of Sciences and Technology, University of Coimbra, Coimbra, Portugal
| | - António F Ambrósio
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI Consortium, University of Coimbra, Coimbra, Portugal.,Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal
| | - Ana R Santiago
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,CNC.IBILI Consortium, University of Coimbra, Coimbra, Portugal.,Faculty of Medicine, University of Coimbra, Coimbra, Portugal.,Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal
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41
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Caglayan B, Caglayan AB, Beker MC, Yalcin E, Beker M, Kelestemur T, Sertel E, Ozturk G, Kilic U, Sahin F, Kilic E. Evidence that activation of P2X7R does not exacerbate neuronal death after optic nerve transection and focal cerebral ischemia in mice. Exp Neurol 2017; 296:23-31. [PMID: 28669743 DOI: 10.1016/j.expneurol.2017.06.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 06/01/2017] [Accepted: 06/29/2017] [Indexed: 12/19/2022]
Abstract
Conflicting data in the literature about the function of P2X7R in survival following ischemia necessitates the conductance of in-depth studies. To investigate the impacts of activation vs inhibition of the receptor on neuronal survival as well as the downstream signaling cascades, in addition to optic nerve transection (ONT), 30min and 90min of middle cerebral artery occlusion (MCAo) models were performed in mice. Intracellular calcium levels were assessed in primary cortical neuron cultures. Here, we show that P2X7R antagonist Brilliant Blue G (BBG) decreased DNA fragmentation, infarct volume, brain swelling, neurological deficit scores and activation of microglial cells after focal cerebral ischemia. BBG also significantly increased the number of surviving retinal ganglion cells (RGCs) after ONT and the number of surviving neurons following MCAo. Importantly, receptor agonist BzATP resulted in increased activation of microglial cells and induced phosphorylation of ERK, AKT and JNK. These results indicated that inhibition of P2X7R with BBG promoted neuronal survival, not through the activation of survival kinase pathways, but possibly by improved intracellular Ca2+ overload and decreased the levels of Caspase 1, IL-1β and Bax proteins. On the other hand, BzATP-mediated increased number of activated microglia and increased survival kinase levels in addition to increased caspase-1 and IL-1β levels indicate the complex nature of the P2X7 receptor-mediated signaling in neuronal injury.
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Affiliation(s)
- Berrak Caglayan
- Istanbul Medipol University, Regenerative and Restorative Medical Research Center, Istanbul, Turkey; Istanbul Medipol University, Dept. of Physiology, Istanbul, Turkey; Yeditepe University, Dept. of Genetics and Bioengineering, Istanbul, Turkey
| | - Ahmet B Caglayan
- Istanbul Medipol University, Regenerative and Restorative Medical Research Center, Istanbul, Turkey; Istanbul Medipol University, Dept. of Physiology, Istanbul, Turkey
| | - Mustafa C Beker
- Istanbul Medipol University, Regenerative and Restorative Medical Research Center, Istanbul, Turkey; Istanbul Medipol University, Dept. of Physiology, Istanbul, Turkey
| | - Esra Yalcin
- Istanbul Medipol University, Regenerative and Restorative Medical Research Center, Istanbul, Turkey; Istanbul Medipol University, Dept. of Physiology, Istanbul, Turkey
| | - Merve Beker
- Bezmialem Vakif University, Dept. of Medical Biology, Istanbul, Turkey
| | - Taha Kelestemur
- Istanbul Medipol University, Regenerative and Restorative Medical Research Center, Istanbul, Turkey; Istanbul Medipol University, Dept. of Physiology, Istanbul, Turkey
| | - Elif Sertel
- Istanbul Medipol University, Regenerative and Restorative Medical Research Center, Istanbul, Turkey; Istanbul Medipol University, Dept. of Physiology, Istanbul, Turkey
| | - Gürkan Ozturk
- Istanbul Medipol University, Regenerative and Restorative Medical Research Center, Istanbul, Turkey; Istanbul Medipol University, Dept. of Physiology, Istanbul, Turkey
| | - Ulkan Kilic
- Istanbul Medipol University, Regenerative and Restorative Medical Research Center, Istanbul, Turkey; Istanbul Medipol University, Medical Biology, Istanbul, Turkey
| | - Fikrettin Sahin
- Yeditepe University, Dept. of Genetics and Bioengineering, Istanbul, Turkey
| | - Ertugrul Kilic
- Istanbul Medipol University, Regenerative and Restorative Medical Research Center, Istanbul, Turkey; Istanbul Medipol University, Dept. of Physiology, Istanbul, Turkey.
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42
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Ye X, Shen T, Hu J, Zhang L, Zhang Y, Bao L, Cui C, Jin G, Zan K, Zhang Z, Yang X, Shi H, Zu J, Yu M, Song C, Wang Y, Qi S, Cui G. Purinergic 2X7 receptor/NLRP3 pathway triggers neuronal apoptosis after ischemic stroke in the mouse. Exp Neurol 2017; 292:46-55. [DOI: 10.1016/j.expneurol.2017.03.002] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2016] [Revised: 02/19/2017] [Accepted: 03/03/2017] [Indexed: 12/31/2022]
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43
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Yue N, Huang H, Zhu X, Han Q, Wang Y, Li B, Liu Q, Wu G, Zhang Y, Yu J. Activation of P2X7 receptor and NLRP3 inflammasome assembly in hippocampal glial cells mediates chronic stress-induced depressive-like behaviors. J Neuroinflammation 2017; 14:102. [PMID: 28486969 PMCID: PMC5424302 DOI: 10.1186/s12974-017-0865-y] [Citation(s) in RCA: 224] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 04/14/2017] [Indexed: 12/24/2022] Open
Abstract
Background In recent years, proinflammatory cytokine interleukin-1β (IL-1β) was considered to play a critical role in the pathogenesis of depression. In addition, P2X7 receptor (P2X7R), a member of the purinergic receptor family, which is predominantly present on microglia, as well as on astrocytes and neurons in lesser amounts in the central nervous system, was suggested to be involved in the processing and releasing of IL-1β. Here, we investigated the role of P2X7R in the pathogenesis of depression. Methods Male Sprague-Dawley rats were subjected to chronic unpredictable stressors (CUS) for 3 weeks. At the end of week 1, 2, and 3, extracellular ATP, caspase 1, IL-1β, and components and activation of NLRP3 inflammasome (nucleotide-binding, leucine-rich repeat, pyrin domain containing 3) were evaluated as biomarker of neuroinflammation. In separate experiments, the rats were microinjected with P2X7R agonists ATP, BzATP, and saline into the hippocampus, respectively, or exposed to CUS combined with hippocampal microinjection with P2X7R antagonist, BBG and A438079, and saline, respectively, for 3 weeks, followed by exposed to forced swimming test and open-field test. Moreover, we also evaluated the depressive and anxiety-like behavior of P2X7-null mice in forced swimming test, open-field test, and elevated plus maze. Results Along with stress accumulation, extracellular ATP, cleaved-caspase 1, IL-1β, and ASC were significantly enhanced in the hippocampus, but P2X7R and NLRP3 were not. Immunoprecipitation assay indicated that along with the accumulation of stress, assembly of NLRP3 inflammasome and cleaved caspase 1 in NLRP3 inflammasome were significantly increased. Moreover, antagonists of P2X7R, either BBG or A438079, prevented the development of depressive-like behaviors induced by chronic unpredictable stress in rats. Meanwhile, we could not observe any depressive-like or anxiety-like behaviors of P2X7-null mice after they had been exposed to CUS. The results implied that P2X7 knockout could impede the development of depressive-like and anxiety-like behaviors induced by CUS. In contrast, chronic administration of agonists of P2X7R, either ATP or BzATP, could induce depressive-like behaviors. Conclusions The activation of P2X7R and subsequent NLRP3 inflammasome in hippocampal microglial cells could mediate depressive-like behaviors, which suggests a new therapeutic target for the prevention and treatment of depression. Electronic supplementary material The online version of this article (doi:10.1186/s12974-017-0865-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Na Yue
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institues of Brain Science, State Key Laboratory of Medical Neurobiology and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China
| | - Huijie Huang
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institues of Brain Science, State Key Laboratory of Medical Neurobiology and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China
| | - Xiaocang Zhu
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institues of Brain Science, State Key Laboratory of Medical Neurobiology and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China
| | - Qiuqin Han
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institues of Brain Science, State Key Laboratory of Medical Neurobiology and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China
| | - Yalin Wang
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institues of Brain Science, State Key Laboratory of Medical Neurobiology and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China
| | - Bing Li
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institues of Brain Science, State Key Laboratory of Medical Neurobiology and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China
| | - Qiong Liu
- Department of Anatomy, Histology and Embryology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, 200032, China.,Key Laboratory of Medical Imaging Computing and Computer Assisted Intervention of Shanghai, Shanghai, 200032, China
| | - Gencheng Wu
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institues of Brain Science, State Key Laboratory of Medical Neurobiology and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China
| | - Yuqiu Zhang
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institues of Brain Science, State Key Laboratory of Medical Neurobiology and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China.
| | - Jin Yu
- Department of Integrative Medicine and Neurobiology, School of Basic Medical Sciences, Institues of Brain Science, State Key Laboratory of Medical Neurobiology and Collaborative Innovation Center for Brain Science, Fudan University, Shanghai, 200032, China.
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44
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Yamashiro K, Fujii Y, Maekawa S, Morita M. Multiple pathways for elevating extracellular adenosine in the rat hippocampal CA1 region characterized by adenosine sensor cells. J Neurochem 2016; 140:24-36. [PMID: 27896810 DOI: 10.1111/jnc.13888] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 10/03/2016] [Accepted: 10/19/2016] [Indexed: 12/17/2022]
Abstract
Extracellular adenosine in the brain, which modulates various physiological and pathological processes, fluctuates in a complicated manner that reflects the circadian cycle, neuronal activity, metabolism, and disease states. The dynamics of extracellular adenosine in the brain are not fully understood, largely because of the lack of simple and reliable methods of measuring time-dependent changes in tissue adenosine distribution. This study describes the development of a biosensor, designated an adenosine sensor cell, expressing adenosine A1 receptor, and a genetically modified G protein. This biosensor was used to characterize extracellular adenosine elevation in brain tissue by measuring intracellular calcium elevation in response to adenosine. Placement of adenosine sensor cells below hippocampal slices successfully detected adenosine releases from these slices in response to neuronal activity and astrocyte swelling by conventional calcium imaging. Pharmacological analyses indicated that high-frequency electrical stimulation-induced post-synaptic adenosine release in a manner dependent on L-type calcium channels and calcium-induced calcium release. Adenosine release following treatments that cause astrocyte swelling is independent of calcium channels, but dependent on aquaporin 4, an astrocyte-specific water channel subtype. The ability of ectonucleotidase inhibitors to inhibit adenosine release following astrocyte swelling, but not electrical stimulation, suggests that the former reflects astrocytic ATP release and subsequent enzymatic breakdown, whereas the latter reflects direct adenosine release from neurons. These results suggest that distinct mechanisms are responsible for extracellular adenosine elevations by neurons and astrocytes, allowing exquisite regulation of extracellular adenosine in the brain.
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Affiliation(s)
- Kunihiko Yamashiro
- Department of Biology, Kobe University Graduate School of Science, Kobe, Japan
| | - Yuki Fujii
- Department of Biology, Kobe University Graduate School of Science, Kobe, Japan
| | - Shohei Maekawa
- Department of Biology, Kobe University Graduate School of Science, Kobe, Japan
| | - Mitsuhiro Morita
- Department of Biology, Kobe University Graduate School of Science, Kobe, Japan
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Guitart X, Bonaventura J, Rea W, Orrú M, Cellai L, Dettori I, Pedata F, Brugarolas M, Cortés A, Casadó V, Chang CP, Narayanan M, Chern Y, Ferré S. Equilibrative nucleoside transporter ENT1 as a biomarker of Huntington disease. Neurobiol Dis 2016; 96:47-53. [PMID: 27567601 DOI: 10.1016/j.nbd.2016.08.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 08/05/2016] [Accepted: 08/22/2016] [Indexed: 02/03/2023] Open
Abstract
The initial goal of this study was to investigate alterations in adenosine A2A receptor (A2AR) density or function in a rat model of Huntington disease (HD) with reported insensitivity to an A2AR antagonist. Unsuspected negative results led to the hypothesis of a low striatal adenosine tone and to the search for the mechanisms involved. Extracellular striatal concentrations of adenosine were measured with in vivo microdialysis in two rodent models of early neuropathological stages of HD disease, the Tg51 rat and the zQ175 knock-in mouse. In view of the crucial role of the equilibrative nucleoside transporter (ENT1) in determining extracellular content of adenosine, the binding properties of the ENT1 inhibitor [3H]-S-(4-Nitrobenzyl)-6-thioinosine were evaluated in zQ175 mice and the differential expression and differential coexpression patterns of the ENT1 gene (SLC29A1) were analyzed in a large human cohort of HD disease and controls. Extracellular striatal levels of adenosine were significantly lower in both animal models as compared with control littermates and striatal ENT1 binding sites were significantly upregulated in zQ175 mice. ENT1 transcript was significantly upregulated in HD disease patients at an early neuropathological severity stage, but not those with a higher severity stage, relative to non-demented controls. ENT1 transcript was differentially coexpressed (gained correlations) with several other genes in HD disease subjects compared to the control group. The present study demonstrates that ENT1 and adenosine constitute biomarkers of the initial stages of neurodegeneration in HD disease and also predicts that ENT1 could constitute a new therapeutic target to delay the progression of the disease.
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Affiliation(s)
- Xavier Guitart
- Integrative Neurobiology Section, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, United States
| | - Jordi Bonaventura
- Integrative Neurobiology Section, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, United States
| | - William Rea
- Integrative Neurobiology Section, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, United States
| | - Marco Orrú
- Integrative Neurobiology Section, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, United States
| | - Lucrezia Cellai
- Department NEUROFARBA, Division of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy
| | - Ilaria Dettori
- Department NEUROFARBA, Division of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy
| | - Felicita Pedata
- Department NEUROFARBA, Division of Pharmacology and Toxicology, University of Florence, 50139 Florence, Italy
| | - Marc Brugarolas
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona and Center for Biomedical Research in Neurodegenerative Diseases Network and Institute of Biomedicine, 08028 Barcelona, Spain
| | - Antonio Cortés
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona and Center for Biomedical Research in Neurodegenerative Diseases Network and Institute of Biomedicine, 08028 Barcelona, Spain
| | - Vicent Casadó
- Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Barcelona and Center for Biomedical Research in Neurodegenerative Diseases Network and Institute of Biomedicine, 08028 Barcelona, Spain
| | - Ching-Pang Chang
- Division of Neuroscience Institute of Biomedical Sciences, Academia Sinica, 11529 Taipei, Taiwan
| | - Manikandan Narayanan
- Systems Genomics and Bioinformatics Unit, Laboratory of Systems Biology, National Institute of Allergy and Infectious Diseases, Intramural Research Program, National Institutes of Health, Bethesda, MD 20892, United States
| | - Yijuang Chern
- Division of Neuroscience Institute of Biomedical Sciences, Academia Sinica, 11529 Taipei, Taiwan
| | - Sergi Ferré
- Integrative Neurobiology Section, National Institute on Drug Abuse, Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, United States.
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Cunha RA. How does adenosine control neuronal dysfunction and neurodegeneration? J Neurochem 2016; 139:1019-1055. [PMID: 27365148 DOI: 10.1111/jnc.13724] [Citation(s) in RCA: 320] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 05/23/2016] [Accepted: 06/23/2016] [Indexed: 12/11/2022]
Abstract
The adenosine modulation system mostly operates through inhibitory A1 (A1 R) and facilitatory A2A receptors (A2A R) in the brain. The activity-dependent release of adenosine acts as a brake of excitatory transmission through A1 R, which are enriched in glutamatergic terminals. Adenosine sharpens salience of information encoding in neuronal circuits: high-frequency stimulation triggers ATP release in the 'activated' synapse, which is locally converted by ecto-nucleotidases into adenosine to selectively activate A2A R; A2A R switch off A1 R and CB1 receptors, bolster glutamate release and NMDA receptors to assist increasing synaptic plasticity in the 'activated' synapse; the parallel engagement of the astrocytic syncytium releases adenosine further inhibiting neighboring synapses, thus sharpening the encoded plastic change. Brain insults trigger a large outflow of adenosine and ATP, as a danger signal. A1 R are a hurdle for damage initiation, but they desensitize upon prolonged activation. However, if the insult is near-threshold and/or of short-duration, A1 R trigger preconditioning, which may limit the spread of damage. Brain insults also up-regulate A2A R, probably to bolster adaptive changes, but this heightens brain damage since A2A R blockade affords neuroprotection in models of epilepsy, depression, Alzheimer's, or Parkinson's disease. This initially involves a control of synaptotoxicity by neuronal A2A R, whereas astrocytic and microglia A2A R might control the spread of damage. The A2A R signaling mechanisms are largely unknown since A2A R are pleiotropic, coupling to different G proteins and non-canonical pathways to control the viability of glutamatergic synapses, neuroinflammation, mitochondria function, and cytoskeleton dynamics. Thus, simultaneously bolstering A1 R preconditioning and preventing excessive A2A R function might afford maximal neuroprotection. The main physiological role of the adenosine modulation system is to sharp the salience of information encoding through a combined action of adenosine A2A receptors (A2A R) in the synapse undergoing an alteration of synaptic efficiency with an increased inhibitory action of A1 R in all surrounding synapses. Brain insults trigger an up-regulation of A2A R in an attempt to bolster adaptive plasticity together with adenosine release and A1 R desensitization; this favors synaptotocity (increased A2A R) and decreases the hurdle to undergo degeneration (decreased A1 R). Maximal neuroprotection is expected to result from a combined A2A R blockade and increased A1 R activation. This article is part of a mini review series: "Synaptic Function and Dysfunction in Brain Diseases".
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Affiliation(s)
- Rodrigo A Cunha
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,FMUC-Faculty of Medicine, University of Coimbra, Coimbra, Portugal
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Ou Y, Chan G, Zuo J, Rattner JB, van der Hoorn FA. Purinergic A2b Receptor Activation by Extracellular Cues Affects Positioning of the Centrosome and Nucleus and Causes Reduced Cell Migration. J Biol Chem 2016; 291:15388-403. [PMID: 27226580 DOI: 10.1074/jbc.m116.721241] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Indexed: 12/20/2022] Open
Abstract
The tight, relative positioning of the nucleus and centrosome in mammalian cells is important for the regulation of cell migration. Under pathophysiological conditions, the purinergic A2b receptor can regulate cell motility, but the underlying mechanism remains unknown. Expression of A2b, normally low, is increased in tissues experiencing adverse physiological conditions, including hypoxia and inflammation. ATP is released from such cells. We investigated whether extracellular cues can regulate centrosome-nucleus positioning and cell migration. We discovered that hypoxia as well as extracellular ATP cause a reversible increase in the distance between the centrosome and nucleus and reduced cell motility. We uncovered the underlying pathway: both treatments act through the A2b receptor and specifically activate the Epac1/RapGef3 pathway. We show that cells lacking A2b do not respond in this manner to hypoxia or ATP but transfection of A2b restores this response, that Epac1 is critically involved, and that Rap1B is important for the relative positioning of the centrosome and nucleus. Our results represent, to our knowledge, the first report demonstrating that pathophysiological conditions can impact the distance between the centrosome and nucleus. Furthermore, we identify the A2b receptor as a central player in this process.
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Affiliation(s)
- Young Ou
- From the Departments of Biochemistry and Molecular Biology and
| | - Gordon Chan
- the Department of Oncology and Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton, Alberta T6G 1Z2, Canada
| | - Jeremy Zuo
- From the Departments of Biochemistry and Molecular Biology and
| | - Jerome B Rattner
- Cell Biology and Anatomy, Cumming School of Medicine, University of Calgary, Calgary, Alberta T2N 4N1, Canada and
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Lietsche J, Imran I, Klein J. Extracellular levels of ATP and acetylcholine during lithium-pilocarpine induced status epilepticus in rats. Neurosci Lett 2015; 611:69-73. [PMID: 26610905 DOI: 10.1016/j.neulet.2015.11.028] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 11/12/2015] [Accepted: 11/17/2015] [Indexed: 01/23/2023]
Abstract
Acetylcholine (ACh) and ATP are rapidly acting neurotransmitters with a putative role in epileptic seizures. In the present study we investigated extracellular concentrations of both neurotransmitters in parallel by microdialysis in rat hippocampus. We found that infusion of neostigmine increases, while calcium-free perfusion and infusion of tetrodotoxin (TTX) decreases, ACh levels. Calcium-free perfusion also decreased ATP levels which were, however, not affected by neostigmine or TTX. During status epilepticus, ACh levels were increased threefold but returned to baseline after the termination of seizures by diazepam. ATP levels were unchanged during status epilepticus but a several-fold increase was seen when AOPCP, an inhibitor of 5'-endonucleotidase, was infused. The results demonstrate an increase of ATP levels during epileptic seizures which, however, was not of neuronal origin.
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Affiliation(s)
- Jana Lietsche
- Department of Pharmacology, College of Pharmacy, Goethe University of Frankfurt, Germany
| | - Imran Imran
- Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan
| | - Jochen Klein
- Department of Pharmacology, College of Pharmacy, Goethe University of Frankfurt, Germany.
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Pedata F, Dettori I, Coppi E, Melani A, Fusco I, Corradetti R, Pugliese AM. Purinergic signalling in brain ischemia. Neuropharmacology 2015; 104:105-30. [PMID: 26581499 DOI: 10.1016/j.neuropharm.2015.11.007] [Citation(s) in RCA: 117] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 11/04/2015] [Accepted: 11/06/2015] [Indexed: 12/18/2022]
Abstract
Ischemia is a multifactorial pathology characterized by different events evolving in the time. After ischemia a primary damage due to the early massive increase of extracellular glutamate is followed by activation of resident immune cells, i.e microglia, and production or activation of inflammation mediators. Protracted neuroinflammation is now recognized as the predominant mechanism of secondary brain injury progression. Extracellular concentrations of ATP and adenosine in the brain increase dramatically during ischemia in concentrations able to stimulate their respective specific P2 and P1 receptors. Both ATP P2 and adenosine P1 receptor subtypes exert important roles in ischemia. Although adenosine exerts a clear neuroprotective effect through A1 receptors during ischemia, the use of selective A1 agonists is hampered by undesirable peripheral effects. Evidence up to now in literature indicate that A2A receptor antagonists provide protection centrally by reducing excitotoxicity, while agonists at A2A (and possibly also A2B) and A3 receptors provide protection by controlling massive infiltration and neuroinflammation in the hours and days after brain ischemia. Among P2X receptors most evidence indicate that P2X7 receptor contribute to the damage induced by the ischemic insult due to intracellular Ca(2+) loading in central cells and facilitation of glutamate release. Antagonism of P2X7 receptors might represent a new treatment to attenuate brain damage and to promote proliferation and maturation of brain immature resident cells that can promote tissue repair following cerebral ischemia. Among P2Y receptors, antagonists of P2Y12 receptors are of value because of their antiplatelet activity and possibly because of additional anti-inflammatory effects. Moreover strategies that modify adenosine or ATP concentrations at injury sites might be of value to limit damage after ischemia. This article is part of the Special Issue entitled 'Purines in Neurodegeneration and Neuroregeneration'.
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Affiliation(s)
- Felicita Pedata
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Viale Pieraccini, 6, 50139 Florence, Italy.
| | - Ilaria Dettori
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Viale Pieraccini, 6, 50139 Florence, Italy
| | - Elisabetta Coppi
- Department of Health Sciences, University of Florence, Viale Pieraccini, 6, 50139 Florence, Italy
| | - Alessia Melani
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Viale Pieraccini, 6, 50139 Florence, Italy
| | - Irene Fusco
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Viale Pieraccini, 6, 50139 Florence, Italy
| | - Renato Corradetti
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Viale Pieraccini, 6, 50139 Florence, Italy
| | - Anna Maria Pugliese
- Department of Neuroscience, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Viale Pieraccini, 6, 50139 Florence, Italy
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50
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Zimmermann H. Extracellular ATP and other nucleotides-ubiquitous triggers of intercellular messenger release. Purinergic Signal 2015; 12:25-57. [PMID: 26545760 DOI: 10.1007/s11302-015-9483-2] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 10/29/2015] [Indexed: 12/21/2022] Open
Abstract
Extracellular nucleotides, and ATP in particular, are cellular signal substances involved in the control of numerous (patho)physiological mechanisms. They provoke nucleotide receptor-mediated mechanisms in select target cells. But nucleotides can considerably expand their range of action. They function as primary messengers in intercellular communication by stimulating the release of other extracellular messenger substances. These in turn activate additional cellular mechanisms through their own receptors. While this applies also to other extracellular messengers, its omnipresence in the vertebrate organism is an outstanding feature of nucleotide signaling. Intercellular messenger substances released by nucleotides include neurotransmitters, hormones, growth factors, a considerable variety of other proteins including enzymes, numerous cytokines, lipid mediators, nitric oxide, and reactive oxygen species. Moreover, nucleotides activate or co-activate growth factor receptors. In the case of hormone release, the initially paracrine or autocrine nucleotide-mediated signal spreads through to the entire organism. The examples highlighted in this commentary suggest that acting as ubiquitous triggers of intercellular messenger release is one of the major functional roles of extracellular nucleotides. While initiation of messenger release by nucleotides has been unraveled in many contexts, it may have been overlooked in others. It can be anticipated that additional nucleotide-driven messenger functions will be uncovered with relevance for both understanding physiology and development of therapy.
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Affiliation(s)
- Herbert Zimmermann
- Institute of Cell Biology and Neuroscience, Molecular and Cellular Neurobiology, Goethe University, Max-von-Laue-Str. 13, Frankfurt am Main, Germany.
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