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Machado NJ, Ardais AP, Nunes A, Szabó EC, Silveirinha V, Silva HB, Kaster MP, Cunha RA. Impact of Coffee Intake on Measures of Wellbeing in Mice. Nutrients 2024; 16:2920. [PMID: 39275237 PMCID: PMC11396897 DOI: 10.3390/nu16172920] [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: 07/23/2024] [Revised: 08/23/2024] [Accepted: 08/25/2024] [Indexed: 09/16/2024] Open
Abstract
Coffee intake is increasingly recognized as a life-style factor associated with the preservation of health, but there is still a debate on the relative effects of caffeinated and decaffeinated coffee. We now tested how the regular drinking of caffeinated and decaffeinated coffee for 3 weeks impacted on the behavior of male and female adult mice. Males drinking caffeinated coffee displayed statistically significant lower weight gain, increased sensorimotor coordination, greater motivation in the splash test, more struggling in the forced swimming test, faster onset of nest building, more marble burying and greater sociability. Females drinking caffeinated coffee displayed statistically significant increased hierarchy fighting, greater self-care and motivation in the splash test and faster onset of nest building. A post-hoc two-way ANOVA revealed sex-differences in the effects of caffeinated coffee (p values for interaction between the effect of caffeinated coffee and sex) on the hierarchy in the tube test (p = 0.044; dominance), in the time socializing (p = 0.044) and in the latency to grooming (p = 0.048; selfcare), but not in the marble burying test (p = 0.089). Intake of decaffeinated coffee was devoid of effects in males and females. Since caffeine targets adenosine receptors, we verified that caffeinated but not decaffeinated coffee intake increased the density of adenosine A1 receptors (A1R) and increased A1R-mediated tonic inhibition of synaptic transmission in the dorsolateral striatum and ventral but not dorsal hippocampus, the effects being more evident in the ventral hippocampus of females and striatum of males. In contrast, caffeinated and decaffeinated coffee both ameliorated the antioxidant status in the frontal cortex. It is concluded that caffeinated coffee increases A1R-mediated inhibition in mood-related areas bolstering wellbeing of both males and females, with increased sociability in males and hierarchy struggling and self-care in females.
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Affiliation(s)
- Nuno J Machado
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Ana Paula Ardais
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Ana Nunes
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Eszter C Szabó
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Vasco Silveirinha
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Henrique B Silva
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Manuella P Kaster
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Rodrigo A Cunha
- CNC-Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal
- Faculty of Medicine, University of Coimbra, 3004-504 Coimbra, Portugal
- MIA-Portugal, Multidisciplinary Institute of Aging, University of Coimbra, 3004-504 Coimbra, Portugal
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Ribeiro DE, Petiz LL, Glaser T, Oliveira-Giacomelli Á, Andrejew R, Saab FDAR, Milanis MDS, Campos HC, Sampaio VFA, La Banca S, Longo BM, Lameu C, Tang Y, Resende RR, Ferreira ST, Ulrich H. Purinergic signaling in cognitive impairment and neuropsychiatric symptoms of Alzheimer's disease. Neuropharmacology 2023; 226:109371. [PMID: 36502867 DOI: 10.1016/j.neuropharm.2022.109371] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 12/04/2022] [Accepted: 12/05/2022] [Indexed: 12/13/2022]
Abstract
About 10 million new cases of dementia develop worldwide each year, of which up to 70% are attributable to Alzheimer's disease (AD). In addition to the widely known symptoms of memory loss and cognitive impairment, AD patients frequently develop non-cognitive symptoms, referred to as behavioral and psychological symptoms of dementia (BPSDs). Sleep disorders are often associated with AD, but mood alterations, notably depression and apathy, comprise the most frequent class of BPSDs. BPSDs negatively affect the lives of AD patients and their caregivers, and have a significant impact on public health systems and the economy. Because treatments currently available for AD are not disease-modifying and mainly aim to ameliorate some of the cognitive symptoms, elucidating the mechanisms underlying mood alterations and other BPSDs in AD may reveal novel avenues for progress in AD therapy. Purinergic signaling is implicated in the pathophysiology of several central nervous system (CNS) disorders, such as AD, depression and sleep disorders. Here, we review recent findings indicating that purinergic receptors, mainly the A1, A2A, and P2X7 subtypes, are associated with the development/progression of AD. Current evidence suggests that targeting purinergic signaling may represent a promising therapeutic approach in AD and related conditions. This article is part of the Special Issue on "Purinergic Signaling: 50 years".
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Affiliation(s)
- Deidiane Elisa Ribeiro
- Department of Biochemistry, Chemistry Institute, University of São Paulo (USP), São Paulo, Brazil.
| | - Lyvia Lintzmaier Petiz
- Department of Biochemistry and Molecular Biology, Universidade Federal do Paraná, Curitiba, Brazil
| | - Talita Glaser
- Department of Biochemistry, Chemistry Institute, University of São Paulo (USP), São Paulo, Brazil
| | | | - Roberta Andrejew
- Department of Biochemistry, Chemistry Institute, University of São Paulo (USP), São Paulo, Brazil
| | | | - Milena da Silva Milanis
- Department of Biochemistry, Chemistry Institute, University of São Paulo (USP), São Paulo, Brazil
| | - Henrique Correia Campos
- Laboratory of Neurophysiology, Department of Physiology, Federal University of São Paulo (UNIFESP), São Paulo, Brazil
| | | | - Sophia La Banca
- Department of Biochemistry, Chemistry Institute, University of São Paulo (USP), São Paulo, Brazil
| | - Beatriz Monteiro Longo
- Laboratory of Neurophysiology, Department of Physiology, Federal University of São Paulo (UNIFESP), São Paulo, Brazil
| | - Claudiana Lameu
- Department of Biochemistry, Chemistry Institute, University of São Paulo (USP), São Paulo, Brazil
| | - Yong Tang
- International Collaborative Centre on Big Science Plan for Purinergic Signalling, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China; Acupuncture and Chronobiology Key Laboratory of Sichuan Province, Chengdu, 610075, China
| | - Rodrigo Ribeiro Resende
- Department of Biochemistry and Immunology, Federal University of Minas Gerais Belo Horizonte, MG, Brazil
| | - Sergio T Ferreira
- Institute of Biophysics Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; Institute of Medical Biochemistry Leopoldo de Meis, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Henning Ulrich
- Department of Biochemistry, Chemistry Institute, University of São Paulo (USP), São Paulo, Brazil; International Collaborative Centre on Big Science Plan for Purinergic Signalling, Chengdu University of Traditional Chinese Medicine, Chengdu, 610075, China.
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3
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IJzerman AP, Jacobson KA, Müller CE, Cronstein BN, Cunha RA. International Union of Basic and Clinical Pharmacology. CXII: Adenosine Receptors: A Further Update. Pharmacol Rev 2022; 74:340-372. [PMID: 35302044 PMCID: PMC8973513 DOI: 10.1124/pharmrev.121.000445] [Citation(s) in RCA: 74] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Our previous International Union of Basic and Clinical Pharmacology report on the nomenclature and classification of adenosine receptors (2011) contained a number of emerging developments with respect to this G protein-coupled receptor subfamily, including protein structure, protein oligomerization, protein diversity, and allosteric modulation by small molecules. Since then, a wealth of new data and results has been added, allowing us to explore novel concepts such as target binding kinetics and biased signaling of adenosine receptors, to examine a multitude of receptor structures and novel ligands, to gauge new pharmacology, and to evaluate clinical trials with adenosine receptor ligands. This review should therefore be considered a further update of our previous reports from 2001 and 2011. SIGNIFICANCE STATEMENT: Adenosine receptors (ARs) are of continuing interest for future treatment of chronic and acute disease conditions, including inflammatory diseases, neurodegenerative afflictions, and cancer. The design of AR agonists ("biased" or not) and antagonists is largely structure based now, thanks to the tremendous progress in AR structural biology. The A2A- and A2BAR appear to modulate the immune response in tumor biology. Many clinical trials for this indication are ongoing, whereas an A2AAR antagonist (istradefylline) has been approved as an anti-Parkinson agent.
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Affiliation(s)
- Adriaan P IJzerman
- Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands (A.P.IJ.); National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Molecular Recognition Section, Bethesda, Maryland (K.A.J.); Universität Bonn, Bonn, Germany (C.E.M.); New York University School of Medicine, New York, New York (B.N.C.); and Center for Neurosciences and Cell Biology and Faculty of Medicine, University of Coimbra, Coimbra, Portugal (R.A.C.)
| | - Kenneth A Jacobson
- Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands (A.P.IJ.); National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Molecular Recognition Section, Bethesda, Maryland (K.A.J.); Universität Bonn, Bonn, Germany (C.E.M.); New York University School of Medicine, New York, New York (B.N.C.); and Center for Neurosciences and Cell Biology and Faculty of Medicine, University of Coimbra, Coimbra, Portugal (R.A.C.)
| | - Christa E Müller
- Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands (A.P.IJ.); National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Molecular Recognition Section, Bethesda, Maryland (K.A.J.); Universität Bonn, Bonn, Germany (C.E.M.); New York University School of Medicine, New York, New York (B.N.C.); and Center for Neurosciences and Cell Biology and Faculty of Medicine, University of Coimbra, Coimbra, Portugal (R.A.C.)
| | - Bruce N Cronstein
- Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands (A.P.IJ.); National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Molecular Recognition Section, Bethesda, Maryland (K.A.J.); Universität Bonn, Bonn, Germany (C.E.M.); New York University School of Medicine, New York, New York (B.N.C.); and Center for Neurosciences and Cell Biology and Faculty of Medicine, University of Coimbra, Coimbra, Portugal (R.A.C.)
| | - Rodrigo A Cunha
- Leiden Academic Centre for Drug Research, Leiden University, Leiden, The Netherlands (A.P.IJ.); National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Molecular Recognition Section, Bethesda, Maryland (K.A.J.); Universität Bonn, Bonn, Germany (C.E.M.); New York University School of Medicine, New York, New York (B.N.C.); and Center for Neurosciences and Cell Biology and Faculty of Medicine, University of Coimbra, Coimbra, Portugal (R.A.C.)
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Frozi J, de Carvalho HW, Ottoni GL, Cunha RA, Lara DR. Distinct sensitivity to caffeine-induced insomnia related to age. J Psychopharmacol 2018; 32:89-95. [PMID: 28879806 DOI: 10.1177/0269881117722997] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Caffeine acts by antagonizing the effect of the endogenous homeostatic sleep factor adenosine. In the current study we aimed to evaluate the pattern of caffeine-induced insomnia and its relation to age and sex in a general population sample derived from a web survey. The sample included 75,534 participants (28.1% men) from 18 to 75 years who answered self-report questionnaires by accessing a website in Brazilian Portuguese (BRAINSTEP project). In our sample, 3620 (17.0%) men and 9920 (18.3%) women reported insomnia due to caffeine intake. Caffeine-induced insomnia increased with aging in both men and women. This difference remained after adjusting for sociodemographic, psychiatric and sleep related variables as well as caffeine intake. Women showed higher proportion of caffeine-induced insomnia than men, but this difference did not remain after controlling for covariates. Also, individuals with caffeine-induced insomnia reported poorer sleep quality, higher latency to fall asleep and a higher proportion of psychiatric diagnoses and daily use of hypnotic drugs. In conclusion, our results show an age-associated increase in caffeine-induced insomnia and poorer mental health indicators among people with caffeine-induced insomnia complaints.
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Affiliation(s)
- Júlia Frozi
- 1 Postgraduate Program in Psychiatry/Residency Program in Psychiatry-Hospital São Lucas-Pontifícia Universidade Católica-PUCRS, Porto Alegre, Brazil.,2 Department of Psychiatry and Legal Medicine, Medical School-PUCRS-Brazil, Porto Alegre, Brazil
| | | | - Gustavo L Ottoni
- 4 Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Brazil
| | - Rodrigo A Cunha
- 5 CNC-Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal.,6 FMUC-Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Diogo R Lara
- 7 Faculty of Biosciences, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil
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Mishina M, Kimura Y, Sakata M, Ishii K, Oda K, Toyohara J, Kimura K, Ishiwata K. Age-Related Decrease in Male Extra-Striatal Adenosine A 1 Receptors Measured Using11C-MPDX PET. Front Pharmacol 2017; 8:903. [PMID: 29326588 PMCID: PMC5741655 DOI: 10.3389/fphar.2017.00903] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 11/28/2017] [Indexed: 11/15/2022] Open
Abstract
Adenosine A1 receptors (A1Rs) are widely distributed throughout the entire human brain, while adenosine A2A receptors (A2ARs) are present in dopamine-rich areas of the brain, such as the basal ganglia. A past study using autoradiography reported a reduced binding ability of A1R in the striatum of old rats. We developed positron emission tomography (PET) ligands for mapping the adenosine receptors and we successfully visualized the A1Rs using 8-dicyclopropylmethyl-1-11C-methyl-3-propylxanthine (11C-MPDX). We previously reported that the density of A1Rs decreased with age in the human striatum, although we could not observe an age-related change in A2ARs. The aim of this study was to investigate the age-related change of the density of A1Rs in the thalamus and cerebral cortices of healthy participants using 11C-MPDX PET. We recruited eight young (22.0 ± 1.7 years) and nine elderly healthy male volunteers (65.7 ± 8.0 years). A dynamic series of decay-corrected PET scans was performed for 60 min starting with the injection of 11C-MPDX. We placed the circular regions of interest of 10 mm in diameter in 11C-MPDX PET images. The values for the binding potential (BPND) of 11C-MPDX in the thalamus, and frontal, temporal, occipital, and parietal cortices were calculated using a graphical analysis, wherein the reference region was the cerebellum. BPND of 11C-MPDX was significantly lower in elderly participants than young participants in the thalamus, and frontal, temporal, occipital, and parietal cortices. In the human brain, we could observe the age-related decrease in the distribution of A1Rs.
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Affiliation(s)
- Masahiro Mishina
- Department of Neuro-pathophysiological Imaging, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan.,Research Team for Neuroimaging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.,Department of Neurological Science, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan
| | - Yuichi Kimura
- Research Team for Neuroimaging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.,Department of Computational Systems Biology, Faculty of Biology-Oriented Science and Technology, Kindai University, Kinokawa, Japan
| | - Muneyuki Sakata
- Research Team for Neuroimaging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan
| | - Kenji Ishii
- Research Team for Neuroimaging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan
| | - Keiichi Oda
- Research Team for Neuroimaging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.,Department of Radiological Technology, Faculty of Health Sciences, Hokkaido University of Science, Sapporo, Japan
| | - Jun Toyohara
- Research Team for Neuroimaging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan
| | - Kazumi Kimura
- Department of Neurological Science, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan
| | - Kiichi Ishiwata
- Research Team for Neuroimaging, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan.,Institute of Cyclotron and Drug Discovery Research, Southern TOHOKU Research Institute for Neuroscience, Koriyama, Japan.,Department of Biofunctional Imaging, Fukushima Medical University, Fukushima, Japan
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Mishina M, Ishii K, Kimura Y, Suzuki M, Kitamura S, Ishibashi K, Sakata M, Oda K, Kobayashi S, Kimura K, Ishiwata K. Adenosine A1receptors measured with11C-MPDX PET in early Parkinson's disease. Synapse 2017; 71. [DOI: 10.1002/syn.21979] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 04/02/2017] [Accepted: 04/10/2017] [Indexed: 01/16/2023]
Affiliation(s)
- Masahiro Mishina
- Department of Neuro-pathophysiological Imaging, Graduate School of Medicine; Nippon Medical School; 1-396 Kosugi, Nakahara Kawasaki Kanagawa 211-8533 Japan
- Research Team for Neuroimaging; Tokyo Metropolitan Institute of Gerontology; 35-2 Sakae-cho Itabashi Tokyo 173-0015 Japan
- Department of Neurology; Nippon Medical School, Musashi Kosugi Hospital; 1-396 Kosugi, Nakahara Kawasaki Kanagawa 211-8533 Japan
| | - Kenji Ishii
- Research Team for Neuroimaging; Tokyo Metropolitan Institute of Gerontology; 35-2 Sakae-cho Itabashi Tokyo 173-0015 Japan
| | - Yuichi Kimura
- Research Team for Neuroimaging; Tokyo Metropolitan Institute of Gerontology; 35-2 Sakae-cho Itabashi Tokyo 173-0015 Japan
- Department of Computational Systems Biology, Faculty of Biology-Oriented Science and Technology; Kinki University; 930 Nishimitani Kinokawa Wakayama 649-6493 Japan
| | - Masahiko Suzuki
- Research Team for Neuroimaging; Tokyo Metropolitan Institute of Gerontology; 35-2 Sakae-cho Itabashi Tokyo 173-0015 Japan
- Department of Neurology; Katsushika Medical Center, The Jikei University School of Medicine; 6-41-2 Aoto Katsushika Tokyo 125-850 Japan
| | - Shin Kitamura
- Department of Neurology; Nippon Medical School, Musashi Kosugi Hospital; 1-396 Kosugi, Nakahara Kawasaki Kanagawa 211-8533 Japan
| | - Kenji Ishibashi
- Research Team for Neuroimaging; Tokyo Metropolitan Institute of Gerontology; 35-2 Sakae-cho Itabashi Tokyo 173-0015 Japan
| | - Muneyuki Sakata
- Research Team for Neuroimaging; Tokyo Metropolitan Institute of Gerontology; 35-2 Sakae-cho Itabashi Tokyo 173-0015 Japan
| | - Keiichi Oda
- Research Team for Neuroimaging; Tokyo Metropolitan Institute of Gerontology; 35-2 Sakae-cho Itabashi Tokyo 173-0015 Japan
- Department of Radiological Technology, Faculty of Health Sciences; Hokkaido University of Science; 7-Jo 15-4-1 Maeda, Teine Sapporo Hokkaido 006-8585 Japan
| | - Shiro Kobayashi
- Department of Neurosurgery; Nippon Medical School, Chiba Hokusoh Hospital; 1715 Kamagari Inzai Chiba 270-1694 Japan
| | - Kazumi Kimura
- Department of Neurological Science, Graduate School of Medicine; Nippon Medical School; 1-1-5 Sendagi Bunkyo Tokyo 113-8602 Japan
| | - Kiichi Ishiwata
- Research Team for Neuroimaging; Tokyo Metropolitan Institute of Gerontology; 35-2 Sakae-cho Itabashi Tokyo 173-0015 Japan
- Institute of Cyclotron and Drug Discovery Research, Southern TOHOKU Research Institute for Neuroscience; 7-1 15 Yatsuyamada Koriyama Fukushima 963-8563 Japan
- Department of Biofunctional Imaging; Fukushima Medical University; 1 Hikariga-oka Fukushima Fukushima 960-1295 Japan
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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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Adenosine A1 Receptor-Mediated Endocytosis of AMPA Receptors Contributes to Impairments in Long-Term Potentiation (LTP) in the Middle-Aged Rat Hippocampus. Neurochem Res 2015; 41:1085-97. [PMID: 26700433 DOI: 10.1007/s11064-015-1799-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 12/09/2015] [Accepted: 12/09/2015] [Indexed: 12/20/2022]
Abstract
Aging causes multiple changes in the mammalian brain, including changes in synaptic signaling. Previous reports have shown increased extracellular adenosine in the aging brain, and we recently reported that activation of adenosine A1 receptors (A1Rs) induces AMPA receptor (AMPAR) internalization in rat hippocampus. This study investigated whether aging-related changes in the rat hippocampus include altered surface expression of adenosine A1 and A2A receptors, and whether these changes correspond to changes in AMPAR surface expression and altered synaptic plasticity. We found reduced A1R surface expression in middle-aged rat hippocampus, and also reduced GluA1 and GluA2 AMPAR subunit surface expression. Using a chemically-induced LTP (cLTP) experimental protocol, we recorded fEPSPs in young (1 month old) and middle-aged (7-12 month old) rat hippocampal slices. There were significant impairments in cLTP in middle-aged slices, suggesting impaired synaptic plasticity. Since we previously showed that the A1R agonist N(6)-cyclopentyladenosine (CPA) reduced both A1Rs and GluA2/GluA1 AMPARs, we hypothesized that the observed impaired synaptic plasticity in middle-aged brains is regulated by A1R-mediated AMPAR internalization by clathrin-mediated endocytosis. Following cLTP, we found a significant increase in GluA1 and GluA2 surface expression in young rats, which was blunted in middle-aged brains or in young brains pretreated with CPA. Blocking A1Rs with 8-cyclopentyl-1,3-dipropylxanthine or AMPAR endocytosis with either Tat-GluA2-3Y peptide or dynasore (dynamin inhibitor) similarly enhanced AMPAR surface expression following cLTP. These data suggest that age-dependent alteration in adenosine receptor expression contributes to increased AMPAR endocytosis and impaired synaptic plasticity in aged brains.
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9
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Gaytan SP, Pasaro R. Neonatal caffeine treatment up-regulates adenosine receptors in brainstem and hypothalamic cardio-respiratory related nuclei of rat pups. Exp Neurol 2012; 237:247-59. [DOI: 10.1016/j.expneurol.2012.06.028] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Revised: 06/08/2012] [Accepted: 06/20/2012] [Indexed: 01/23/2023]
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10
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Scherer EBS, Schmitz F, Vuaden FC, Savio LEB, Ferreira AGK, Tasca RAJC, Casali EA, Bogo MR, Bonan CD, Wyse ATS. Mild hyperhomocysteinemia alters extracellular adenine metabolism in rat brain. Neuroscience 2012; 223:28-34. [PMID: 22863571 DOI: 10.1016/j.neuroscience.2012.07.035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Revised: 07/10/2012] [Accepted: 07/23/2012] [Indexed: 12/20/2022]
Abstract
Since homocysteine (Hcy) is considered a risk factor to cerebral diseases and adenine nucleotides are important molecules to brain normal function, in the present study we investigated the effect of chronic mild hyperhomocysteinemia on ectonucleotidase activities and expression in rat cerebral cortex. The levels of ATP, ADP, AMP and adenosine (Ado) in cerebrospinal fluid (CSF) of adult rats also were evaluated by high-performance liquid chromatography. For the chronic chemically induced mild hyperhomocysteinemia, Hcy (0.03 μmol/g of body weight) was administered subcutaneously from the 30th to the 60th day of life. Control rats received saline solution in the same volumes. Results showed that Hcy significantly decreased nucleotide hydrolysis in the synaptosomal fraction and increased E-NTPDase1 and ecto-5'-nucleotidase transcripts in rat cerebral cortex. ATP levels were significantly increased, while Ado decreased in CSF of Hcy-treated rats. These findings suggest that the unbalance in ATP and Ado levels may be, at last in part, involved in the cerebral toxicity of mild hyperhomocysteinemia.
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Affiliation(s)
- E B S Scherer
- Laboratório de Neuroproteção e Doenças Neurometabólicas, Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
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Mishina M, Kimura Y, Naganawa M, Ishii K, Oda K, Sakata M, Toyohara J, Kobayashi S, Katayama Y, Ishiwata K. Differential effects of age on human striatal adenosine A₁ and A(2A) receptors. Synapse 2012; 66:832-9. [PMID: 22623181 DOI: 10.1002/syn.21573] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Revised: 05/01/2012] [Accepted: 05/14/2012] [Indexed: 01/19/2023]
Abstract
The aim of this study was to investigate the effect of age on the distribution of adenosine A₁ receptors (A₁Rs) and adenosine A(2A) receptors (A(2A)Rs) in the striatum of healthy subjects using PET imaging with 8-dicyclopropylmethyl-1-[¹¹C]methyl-3-propylxanthine ([¹¹C]MPDX) and [7-methyl-¹¹C]-(E)-8-(3,4,5-trimethoxystyryl)-1,3,7-trimethylxanthine ([¹¹C]TMSX), respectively. We recruited 8 young (22.0 ± 1.7 years) and 10 elderly (65.4 ± 7.6 years) volunteers to undergo [¹¹C]MPDX PET scanning, and 11 young (22.7 ± 2.7 years) and six elderly (60.7 ± 8.5 years) volunteers to undergo [¹¹C]TMSX PET scanning. A dynamic series of decay-corrected PET scans was performed for 60 min following injection of [¹¹C]MPDX or [¹¹C]TMSX. We calculated the binding potential (BP(ND) ) of [¹¹C]MPDX and distribution volume ratio (DVR) of [¹¹C]TMSX in the striatum. The BP(ND) of [¹¹C]MPDX was significantly lower in elderly than in young subjects, both in the putamen and head of the caudate nucleus. The BP(ND) was negatively correlated with age in both the putamen and the head of the caudate nucleus. However, no difference was found between the DVR of [¹¹C]TMSX in the striata of young and elderly subjects, nor was there a correlation between age and the DVR of [¹¹C]TMSX. The effect of age on the distribution of A₁Rs in the human striatum described herein is similar to previous reports of age-related decreases in dopamine D₁ and D₂ receptors. Unlike A₁Rs, however, this study suggests that the distribution of A(2A) Rs does not change with age.
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Affiliation(s)
- Masahiro Mishina
- The Second Department of Internal Medicine, Nippon Medical School, Bunkyo-Ku, Tokyo, Japan; Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, Itabashi-Ku, Tokyo, Japan.
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12
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Endogenous adenosine induces NMDA receptor-independent persistent epileptiform discharges in dorsal and ventral hippocampus via activation of A2 receptors. Epilepsy Res 2012; 100:157-67. [DOI: 10.1016/j.eplepsyres.2012.02.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Revised: 01/14/2012] [Accepted: 02/11/2012] [Indexed: 11/19/2022]
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13
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Perlaki G, Orsi G, Kovacs N, Schwarcz A, Pap Z, Kalmar Z, Plozer E, Csatho A, Gabriel R, Komoly S, Janszky I, Janszky J. Coffee consumption may influence hippocampal volume in young women. Brain Imaging Behav 2011; 5:274-84. [DOI: 10.1007/s11682-011-9131-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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14
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Costenla AR, Diógenes MJ, Canas PM, Rodrigues RJ, Nogueira C, Maroco J, Agostinho PM, Ribeiro JA, Cunha RA, de Mendonça A. Enhanced role of adenosine A2A receptors in the modulation of LTP in the rat hippocampus upon ageing. Eur J Neurosci 2011; 34:12-21. [DOI: 10.1111/j.1460-9568.2011.07719.x] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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15
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Castillo CA, León D, Ruiz MA, Albasanz JL, Martín M. Modulation of adenosine A1 and A2A receptors in C6 glioma cells during hypoxia: involvement of endogenous adenosine. J Neurochem 2010; 105:2315-29. [PMID: 18315561 DOI: 10.1111/j.1471-4159.2008.05314.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
During hypoxia, extracellular adenosine levels are increased to prevent cell damage, playing a neuroprotective role mainly through adenosine A(1) receptors. The aim of the present study was to analyze the effect of hypoxia in both adenosine A(1) and A(2A) receptors endogenously expressed in C6 glioma cells. Two hours of hypoxia (5% O(2)) caused a significant decrease in adenosine A(1) receptors. The same effect was observed at 6 h and 24 h of hypoxia. However, adenosine A(2A) receptors were significantly increased at the same times. These effects were not due to hypoxia-induced alterations in cells number or viability. Changes in receptor density were not associated with variations in the rate of gene expression. Furthermore, hypoxia did not alter HIF-1alpha expression in C6 cells. However, HIF-3alpha, CREB and CREM were decreased. Adenosine A(1) and A(2A) receptor density in normoxic C6 cells treated with adenosine for 2, 6 and 24 h was similar to that observed in cells after oxygen deprivation. When C6 cells were subjected to hypoxia in the presence of adenosine deaminase, the density of receptors was not significantly modulated. Moreover, DPCPX, an A(1) receptor antagonist, blocked the effects of hypoxia on these receptors, while ZM241385, an A(2A) receptor antagonist, was unable to prevent these changes. These results suggest that moderate hypoxia modulates adenosine receptors and cAMP response elements in glial cells, through a mechanism in which endogenous adenosine and tonic A(1) receptor activation is involved.
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Affiliation(s)
- Carlos A Castillo
- Departamento de Química Inorgánica, Orgánica y Bioquímica, Facultad de Químicas, Centro Regional de Investigaciones Biomédicas, Universidad de Castilla-La Mancha, Ciudad Real, Spain
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16
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Brown M, Storlien L, Huang XF, Tapsell L, Else P, Higgins J, Brown I. Dietary Fat and Carbohydrate Composition. Front Neurosci 2009. [DOI: 10.1201/9781420067767-c21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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17
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Rytkönen KM, Wigren HK, Kostin A, Porkka-Heiskanen T, Kalinchuk AV. Nitric oxide mediated recovery sleep is attenuated with aging. Neurobiol Aging 2008; 31:2011-9. [PMID: 19058880 DOI: 10.1016/j.neurobiolaging.2008.10.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2008] [Revised: 09/27/2008] [Accepted: 10/11/2008] [Indexed: 11/28/2022]
Abstract
Nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) in the cholinergic basal forebrain (BF) during sleep deprivation (SD) is implicated in adenosine (AD) release and induction of recovery sleep. Aging is associated with impairments in sleep homeostasis, such as decrease in non-rapid eye movement sleep (NREM) intensity following SD. We hypothesized that age related changes in sleep homeostasis may be induced by impairments in NO-mediated sleep induction. To test this hypothesis we measured levels of NO and iNOS in the BF during SD as well as recovery sleep after SD and NO-donor (DETA/NO) infusion into the BF in three age groups of rats (young, 4 months; middle-aged, 14 months; old, 24 months). We found that in aged rats as compared to young (1) recovery NREM sleep intensity was significantly decreased, (2) neither iNOS nor NO increased in the BF during SD, and (3) DETA/NO infusion failed to induce sleep. Together, these results support our hypothesis that aging impairs the mechanism through which NO in the BF induces sleep.
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18
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Neerhof MG, Jilling T, Synowiec S, Khan S, Thaete LG. Altered endothelin receptor binding in response to nitric oxide synthase inhibition in the pregnant rat. Reprod Sci 2008; 15:366-73. [PMID: 18325929 DOI: 10.1177/1933719107312627] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The authors evaluate the expression of endothelin-1 (ET-1) and its receptors in the uterus and placenta during maternal nitric oxide synthase (NOS) inhibition. Timed-pregnant rats received L-NAME (2.5 mg/kg/h) or saline from day 14 to 21 of gestation. Uterine and placental tissues collected on day 21 were assayed for preproET-1, ET( A), and ET(B) mRNA expression; localization and expression of ET-1 and receptor proteins; and receptor activity. NOS inhibition did not affect preproET-1 mRNA expression in the placenta or uterus. ET(A) expression decreased in the uterine free wall, but no other changes in receptor mRNA expression were observed in the uterus or placenta. ET-1 and receptor proteins were unchanged. Placental ET(A) and ET(B) receptor binding decreased. Uterine ET(A) receptor binding decreased in the placental bed. ET-1, a prominent mediator during NOS inhibition, is not of uterine or placental origin. Reduced receptor binding activity is the primary means by which these tissues regulate their response to ET-1 in the setting of NOS inhibition.
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Affiliation(s)
- Mark G Neerhof
- Department of Obstetrics, Evanston Northwestern Healthcare, Evanston, Illinois, USA
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19
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Thaete LG, Jilling T, Synowiec S, Khan S, Neerhof MG. Expression of endothelin 1 and its receptors in the hypoxic pregnant rat. Biol Reprod 2007; 77:526-32. [PMID: 17554077 PMCID: PMC1989130 DOI: 10.1095/biolreprod.107.061820] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Endothelin 1 (EDN1) plays a primary role in the pathophysiology of hypoxia-induced fetal growth restriction in the rat. In this study we evaluated the effects of chronic maternal hypoxia on the expression of endothelin and its receptors and on receptor binding activity in the uterus and placenta of the rat, in order to elucidate their roles in hypoxia-induced fetal growth restriction. Timed-pregnant Sprague-Dawley rats were maintained in either a normoxic or a normobaric hypoxic (12% O(2)) atmosphere from Gestational Days 18-21. Uterine and placental tissues collected on Gestational Day 21 were assayed for Edn1, Ednra, and Ednrb (endothelin receptors) mRNA expression by real-time quantitative RT-PCR, for localization of EDN1 and its receptors by immunohistochemistry, for EDNRA and EDNRB protein expression by Western blot, and for receptor binding activity by homologous competitive binding assays. EDN1 mRNA expression was significantly increased in the hypoxic placenta, but not in the uterus, compared with normoxic controls. Immunohistochemistry revealed increased EDN1 specifically in the labyrinth of the placenta. Receptor mRNA levels were not significantly affected by hypoxia, but EDNRA protein expression was significantly decreased specifically in the uterine placental beds. Receptor binding decreased significantly in response to hypoxia in all tissues investigated, compared with controls. These results suggest that chronic maternal hypoxia results in increased expression of EDN1 in the placenta but not in the uterus, and that reduced binding activity, rather than regulation of receptor expression, is a mechanism by which these tissues regulate the local hemodynamic response to increased endogenous placental EDN1 in the setting of hypoxia.
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MESH Headings
- Animals
- Binding, Competitive
- Blotting, Western
- Endothelin-1/biosynthesis
- Endothelin-1/genetics
- Endothelin-1/metabolism
- Female
- Hypoxia/metabolism
- Immunohistochemistry
- Male
- Placenta/metabolism
- Pregnancy
- Pregnancy Complications/metabolism
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
- Rats
- Rats, Sprague-Dawley
- Receptor, Endothelin A/biosynthesis
- Receptor, Endothelin A/genetics
- Receptor, Endothelin A/metabolism
- Receptor, Endothelin B/biosynthesis
- Receptor, Endothelin B/genetics
- Receptor, Endothelin B/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Uterus/metabolism
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Affiliation(s)
- Larry G Thaete
- Department of Obstetrics and Gynecology, Evanston Northwestern Healthcare, Evanston, Illinois 60201, USA.
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20
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Meyer PT, Elmenhorst D, Boy C, Winz O, Matusch A, Zilles K, Bauer A. Effect of aging on cerebral A1 adenosine receptors: A [18F]CPFPX PET study in humans. Neurobiol Aging 2006; 28:1914-24. [PMID: 16996650 DOI: 10.1016/j.neurobiolaging.2006.08.005] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2006] [Revised: 07/31/2006] [Accepted: 08/15/2006] [Indexed: 11/20/2022]
Abstract
Cerebral A(1) adenosine receptors (A(1)AR) fulfill important neuromodulatory and homeostatic functions. The present study examines possible age-related A(1)AR changes in living humans by positron emission tomography (PET) and the A(1)AR ligand [(18)F]CPFPX. Thirty-six healthy volunteers aged 22-74 years were included. The apparent binding potential (BP'2) of [(18)F]CPFPX in various cerebral regions was calculated non-invasively using the cerebellum as reference region. In addition, the total distribution volume (DV't) was assessed in 10 subjects undergoing arterial blood sampling. There was no significant association between regional DV't and age, gender, caffeine consumption or sleep duration. BP'2 showed a significant age-dependent decrease in all regions except cingulate gyrus (p=0.062). The BP'2 decline ranged from -17% (striatum) to -34% (postcentral gyrus), the average cortical decline being -23%. There was no significant effect of gender, caffeine consumption and sleep duration on BP'2. In line with in vitro animal studies, the present in vivo PET study detected an age-dependent A(1)AR loss in humans that may be of pathophysiological importance in various neurological diseases associated with aging. Because of the discrepant results of the invasive (DV't) and the non-invasive (BP'2) analyses the present study needs further validation.
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Affiliation(s)
- Philipp T Meyer
- Institute of Medicine/Brain Imaging Center West, Research Center Juelich, 52425 Juelich, Germany
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21
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Coelho JE, Rebola N, Fragata I, Ribeiro JA, de Mendonça A, Cunha RA. Hypoxia-induced desensitization and internalization of adenosine A1 receptors in the rat hippocampus. Neuroscience 2006; 138:1195-203. [PMID: 16442739 DOI: 10.1016/j.neuroscience.2005.12.012] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2005] [Revised: 10/21/2005] [Accepted: 12/02/2005] [Indexed: 12/20/2022]
Abstract
Activation of A1 adenosine receptors is important for both the neuromodulatory and neuroprotective effects of adenosine. However, short periods of global ischemia decrease A1 adenosine receptor density in the brain and it is not known if a parallel loss of functional efficiency of A1 adenosine receptors occurs. We now tested if hypoxia leads to changes in the density and efficiency of A1 adenosine receptors to inhibit excitatory synaptic transmission in rat hippocampal slices. In control conditions, the adenosine analog 2-chloroadenosine, inhibited field excitatory post-synaptic potentials with an EC50 of 0.23 microM. After hypoxia (95% N2 and 5% CO2, for 60 min) and reoxygenation (30 min), the EC50 increased to 0.73 microM. This EC50 shift was prevented by the presence of the A1 adenosine receptor antagonist 8-phenyltheophyline, but not by the A(2A)R antagonist 7-(2-phenylethyl)-5-amino-2-(2-furyl)-pyrazolo-[4,3-e]-1,2,4-triazolo[1,5-c] pyrimidine, during the hypoxic period. This decreased efficiency of A1 adenosine receptors was not paralleled by a global change of A1 adenosine receptor density or affinity (as evaluated by the binding parameters obtained in nerve terminal membranes). However, the density of biotinylated A1 adenosine receptors at the plasma membrane of nerve terminals was reduced by 30% upon hypoxia/reoxygenation, in a manner prevented by the A1 adenosine receptor antagonist 1,3-dipropyl-8-cyclopentylxanthine and mimicked by prolonged (60 min) supra-maximal activation of A1 adenosine receptors with 2-chloroadenosine (10 microM). These results indicate that hypoxia leads to a rapid (<90 min) homologous desensitization of A1 adenosine receptor-mediated inhibition of synaptic transmission that is likely due to an internalization of A1 adenosine receptors in nerve terminals.
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Affiliation(s)
- J E Coelho
- Laboratory of Neurosciences, Institute of Molecular Medicine, Faculty of Medicine, University of Lisbon, 1649-028 Lisboa, Portugal
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22
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du Bois TM, Deng C, Bell W, Huang XF. Fatty acids differentially affect serotonin receptor and transporter binding in the rat brain. Neuroscience 2006; 139:1397-403. [PMID: 16600514 DOI: 10.1016/j.neuroscience.2006.02.068] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2005] [Revised: 01/30/2006] [Accepted: 02/22/2006] [Indexed: 11/24/2022]
Abstract
The aim of this study was to examine the influence of different fat diets on serotonin receptor and transporter binding. Male Sprague-Dawley rats were fed a diet of either high saturated fat, omega-6 polyunsaturated fatty acid, omega-3 polyunsaturated fatty acid or low fat (control) for eight weeks. Using Beta-Imager quantification techniques, [(3)H]ketanserin, [(3)H]mesulergine and [(3)H]paroxetine binding to serotonin (5-HT)(2A), 5-HT(2C) receptors and 5-HT transporters (5-HTT) was measured throughout the brain in all four groups. All three high fatty acid diets influenced serotonin receptor binding, however the most pronounced effects were that compared with the low fat control group, i) 5-HT(2A) receptor binding was increased in the caudate putamen, but reduced in the mammillary nucleus in high saturated fat and high omega-6 polyunsaturated fatty acid diet groups; ii) 5-HT(2C) receptor binding was reduced in the mamillary nucleus of saturated fat group and reduced in prefrontal cortex of the omega-6 polyunsaturated fatty acid and omega-3 polyunsaturated fatty acid groups; and iii) 5-HTT binding was reduced in the hippocampus in the omega-6 polyunsaturated fatty acid group. Overall, the omega-6 polyunsaturated fatty acid diet exerted the most influence on serotonin receptor and transporter binding. These results may be of importance in relation to neuropsychiatric diseases such as schizophrenia, where associations between altered fatty acid levels and the serotonergic system have been made.
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Affiliation(s)
- T M du Bois
- Neuroscience Institute for Schizophrenia and Allied Disorders, Neurobiology Research Centre for Metabolic and Psychiatric Disorders, Department of Biomedical Science, University of Wollongong, Wollongong, NSW, Australia.
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23
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Bordayo EZ, Fawcett JR, Lagalwar S, Svitak AL, Frey WH. Inhibition of ligand binding to G protein-coupled receptors by arachidonic acid. J Mol Neurosci 2005; 27:185-94. [PMID: 16186629 DOI: 10.1385/jmn:27:2:185] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2005] [Accepted: 03/24/2005] [Indexed: 11/11/2022]
Abstract
Arachidonic acid (AA), released in response to muscarinic acetylcholine receptor (mAChR) stimulation, previously has been reported to function as a reversible feedback inhibitor of the mAChR. To determine if the effects of AA on binding to the mAChR are subtype specific and whether AA inhibits ligand binding to other G protein-coupled receptors (GPCRs), the effects of AA on ligand binding to the mAChR subtypes (M1, M2, M3, M4, and M5) and to the micro-opioid receptor, beta2-adrenergic receptor (beta2-AR), 5-hydroxytryptamine receptor (5-HTR), and nicotinic receptors were examined. AA was found to inhibit ligand binding to all mAChR subtypes, to the beta2-AR, the 5-HTR, and to the micro-opioid receptor. However, AA does not inhibit ligand binding to the nicotinic receptor, even at high concentrations of AA. Thus, AA inhibits several types of GPCRs, with 50% inhibition occurring at 3-25 MuM, whereas the nicotinic receptor, a non-GPCR, remains unaffected. Further research is needed to determine the mechanism by which AA inhibits GPCR function.
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Affiliation(s)
- Elizabeth Z Bordayo
- Alzheimer's Research Center, HealthPartners Research Foundation, Saint Paul, MN 55101-2502, USA
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24
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Cunha RA. Neuroprotection by adenosine in the brain: From A(1) receptor activation to A (2A) receptor blockade. Purinergic Signal 2005; 1:111-34. [PMID: 18404497 PMCID: PMC2096528 DOI: 10.1007/s11302-005-0649-1] [Citation(s) in RCA: 404] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2004] [Accepted: 11/10/2004] [Indexed: 12/11/2022] Open
Abstract
Adenosine is a neuromodulator that operates via the most abundant inhibitory adenosine A(1) receptors (A(1)Rs) and the less abundant, but widespread, facilitatory A(2A)Rs. It is commonly assumed that A(1)Rs play a key role in neuroprotection since they decrease glutamate release and hyperpolarize neurons. In fact, A(1)R activation at the onset of neuronal injury attenuates brain damage, whereas its blockade exacerbates damage in adult animals. However, there is a down-regulation of central A(1)Rs in chronic noxious situations. In contrast, A(2A)Rs are up-regulated in noxious brain conditions and their blockade confers robust brain neuroprotection in adult animals. The brain neuroprotective effect of A(2A)R antagonists is maintained in chronic noxious brain conditions without observable peripheral effects, thus justifying the interest of A(2A)R antagonists as novel protective agents in neurodegenerative diseases such as Parkinson's and Alzheimer's disease, ischemic brain damage and epilepsy. The greater interest of A(2A)R blockade compared to A(1)R activation does not mean that A(1)R activation is irrelevant for a neuroprotective strategy. In fact, it is proposed that coupling A(2A)R antagonists with strategies aimed at bursting the levels of extracellular adenosine (by inhibiting adenosine kinase) to activate A(1)Rs might constitute the more robust brain neuroprotective strategy based on the adenosine neuromodulatory system. This strategy should be useful in adult animals and especially in the elderly (where brain pathologies are prevalent) but is not valid for fetus or newborns where the impact of adenosine receptors on brain damage is different.
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Affiliation(s)
- Rodrigo A Cunha
- Center for Neuroscience of Coimbra, Institute of Biochemistry, Faculty of Medicine, University of Coimbra, Coimbra, Portugal,
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25
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du Bois TM, Bell W, Deng C, Huang XF. A high n-6 polyunsaturated fatty acid diet reduces muscarinic M2/M4 receptor binding in the rat brain. J Chem Neuroanat 2005; 29:282-8. [PMID: 15927789 DOI: 10.1016/j.jchemneu.2005.03.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2004] [Revised: 03/07/2005] [Accepted: 03/08/2005] [Indexed: 11/20/2022]
Abstract
The aim of this study was to examine the influence of different fat diets on muscarinic acetylcholine receptor binding. Nineteen male Sprague-Dawley rats were divided into four groups and fed a diet of either high saturated fat, n-6 polyunsaturated fatty acid (PUFA), n-3 PUFA or low fat (control) for 8 weeks. Using quantitative autoradiography, [(3)H]pirenzepine binding to muscarinic M1/M4 receptors and [(3)H]AF-DX384 binding to M2/M4 receptors were measured throughout the brain in all four groups. The main findings were that compared to the low fat control group, M2/M4 receptor binding was significantly reduced in the dorsolateral, dorsomedial and ventromedial parts of the caudate putamen (61-64%, p < 0.05), anterior cingulate cortex (59%, p < 0.01), dentate gyrus and CA1-3 fields of the hippocampus (32-43%, p < 0.01) of rats on a high n-6 PUFA diet; however, no differences in M1/M4 receptor binding densities between the four groups were observed. These results suggest that a diet high in n-6 PUFA, but not of n-3 PUFAs or saturated fat, may selectively alter M2/M4 receptor-mediated signal transduction in the rat brain.
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MESH Headings
- Acetylcholine/metabolism
- Animals
- Arachidonic Acid/metabolism
- Binding, Competitive/drug effects
- Binding, Competitive/physiology
- Brain/drug effects
- Brain/metabolism
- Brain Mapping
- Down-Regulation/drug effects
- Down-Regulation/physiology
- Fatty Acids, Omega-3/metabolism
- Fatty Acids, Omega-3/pharmacology
- Fatty Acids, Omega-6/metabolism
- Fatty Acids, Omega-6/pharmacology
- Food, Formulated
- Food, Fortified
- Male
- Muscarinic Antagonists/metabolism
- Parasympatholytics/metabolism
- Pirenzepine/metabolism
- Radioligand Assay
- Rats
- Rats, Sprague-Dawley
- Receptor, Muscarinic M2/drug effects
- Receptor, Muscarinic M2/metabolism
- Receptor, Muscarinic M4/drug effects
- Receptor, Muscarinic M4/metabolism
- Signal Transduction/drug effects
- Synaptic Transmission/physiology
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Affiliation(s)
- Teresa Marie du Bois
- Neuroscience Institute of Schizophrenia and Allied Disorders (NISAD), Molecular Neurobiology Laboratory, Department of Biomedical Science, University of Wollongong, NSW, Australia
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26
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Fredholm BB, Chen JF, Cunha RA, Svenningsson P, Vaugeois JM. Adenosine and Brain Function. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2005; 63:191-270. [PMID: 15797469 DOI: 10.1016/s0074-7742(05)63007-3] [Citation(s) in RCA: 500] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Bertil B Fredholm
- Department of Physiology and Pharmacology, Karolinska Institutet Stockholm, Sweden
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27
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Rebola N, Canas PM, Oliveira CR, Cunha RA. Different synaptic and subsynaptic localization of adenosine A2A receptors in the hippocampus and striatum of the rat. Neuroscience 2005; 132:893-903. [PMID: 15857695 DOI: 10.1016/j.neuroscience.2005.01.014] [Citation(s) in RCA: 154] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2004] [Revised: 01/03/2005] [Accepted: 01/06/2005] [Indexed: 11/30/2022]
Abstract
Adenosine A(2A) receptors are most abundant in the striatum where they control the striatopallidal pathway thus controlling locomotion. Extra-striatal A(2A) receptors are considerably less abundant but their blockade confers robust neuroprotection. We now have investigated if striatal and extra-striatal A(2A) receptors have a different neuronal location to understand their different functions. The binding density of the A(2A) antagonist, [(3)H]-7-(2-phenylethyl)-5-amino-2-(2-furyl)pyrazolo[4,3e][1,2,4]triazolo[1,5-c]pyrimidine ([(3)H]SCH 58261), was enriched in nerve terminals membranes (B(max)=103+/-12 fmol/mg protein) compared with total membranes (B(max)=29+/-4 fmol/mg protein) from the hippocampus, the same occurring with A(2A) receptor immunoreactivity. In contrast, there was no enrichment of [(3)H]SCH 58261 binding or A(2A) receptor immunoreactivity in synaptosomal compared with total membranes from the striatum. Further subcellular fractionation of hippocampal nerve terminals revealed that A(2A) receptor immunoreactivity was enriched in the active zone of presynaptic nerve terminals, whereas it was predominantly located in the postsynaptic density in the striatum, although a minority of striatal A(2A) receptors were located in the presynaptic active zone. These results indicate that A(2A) receptors in the striatum are not enriched in synapses in agreement with the preponderant role of A(2A) receptors in signal processing in striatopallidal neurons. In contrast, hippocampal A(2A) receptors are enriched in synapses, mainly in the active zone, in accordance with their role in controlling neurotransmitter release. This regional variation in the neuronal distribution of A(2A) receptors reinforces the care required to extrapolate our knowledge from striatal A(2A) receptors to other brain preparations.
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Affiliation(s)
- N Rebola
- Center for Neurosciences of Coimbra, Institute of Biochemistry, Faculty of Medicine, University of Coimbra, Portugal
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Meyer PT, Bier D, Holschbach MH, Boy C, Olsson RA, Coenen HH, Zilles K, Bauer A. Quantification of cerebral A1 adenosine receptors in humans using [18F]CPFPX and PET. J Cereb Blood Flow Metab 2004; 24:323-33. [PMID: 15091113 DOI: 10.1097/01.wcb.0000110531.48786.9d] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Adenosine is an important neuromodulator. Basic cerebral effects of adenosine are exerted by the A1 adenosine receptor (A1AR), which is accessible in vivo by the novel ligand [F]8-cyclopentyl-3-(3-fluoropropyl)-1-propylxanthine ([F]CPFPX) and positron emission tomography (PET). The present study investigates the applicability of kinetic models to describe the cerebral kinetics of [F]CPFPX in order to quantify A1AR density in vivo. Six healthy volunteers underwent dynamic PET scanning and arterial blood sampling after bolus injection of [F]CPFPX. For quantitative analysis, a standard two-tissue compartment model (2TCM) was compared with a one-tissue compartment model (1TCM) and Logan's graphical analysis (GA). The 2TCM described the cerebral kinetics of [F]CPFPX significantly better than the 1TCM (in all regions and subjects examined). The estimated values of the regional total distribution volumes (DVt) correlated strongly between the 2TCM and GA (linear regression r = 0.99, slope: 1.007). The DVt correlation between the 2TCM and the 1TCM was comparably high, but there was a significant bias towards lower DVt estimates given by the 1TCM (r: 0.99, slope: 0.929). It is concluded that a 2TCM satisfactorily accounts for the cerebral kinetics of [F]CPFPX. GA represents an attractive alternative method of analysis.
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Affiliation(s)
- Philipp T Meyer
- Institute of Medicine, Research Center Juelich, Juelich, Germany.
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Ashton KJ, Nilsson U, Willems L, Holmgren K, Headrick JP. Effects of aging and ischemia on adenosine receptor transcription in mouse myocardium. Biochem Biophys Res Commun 2003; 312:367-72. [PMID: 14637147 DOI: 10.1016/j.bbrc.2003.10.127] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The well-documented age-related change in ischemic tolerance may result from impaired adenosine-mediated cardioprotection. Additionally, ischemia itself may potentially modify adenosine signalling, contributing to the post-ischemic phenotype. This study investigates age- and ischemia-dependent changes in adenosine receptor transcript levels (Adora) for the A(1), A(2A), A(2B), and A(3) receptor subtypes in mouse myocardium. Hearts from young (2-4 months) and moderately aged (16-18 months) mice were subjected to 20-min ischemia and 45-min reperfusion. Ischemic tolerance was impaired in aged hearts, which recovered less than 30% ventricular pressure development (compared with approximately 70% in young hearts), and lost 2-fold higher levels of lactate dehydrogenase during reperfusion (reflecting cellular disruption). Real-time PCR analyses revealed an age-related decline in Adora3 levels and induction of Adora2B. Curiously, this effect was mimicked by ischemia, which acutely reduced Adora3 levels and induced Adora2B in young (but not old) hearts. In contrast, in aged hearts ischemia selectively reduced levels of Adora1 transcript ( approximately 2-fold) without altering transcript levels for the other receptors. These results demonstrate selective modulation of cardioprotective adenosine receptor transcription by both aging and ischemia. Reduced A(3) adenosine receptor transcription may contribute to impaired ischemic tolerance in aged hearts, whereas changes in Adora transcription induced by ischemia may impact on the post-ischemic phenotype at later time points.
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Affiliation(s)
- Kevin J Ashton
- Heart Foundation Research Centre, Griffith University Gold Coast, Southport, Qld 4217, Australia
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30
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Rebola N, Coelho JE, Costenla AR, Lopes LV, Parada A, Oliveira CR, Soares-da-Silva P, de Mendonça A, Cunha RA. Decrease of adenosine A1 receptor density and of adenosine neuromodulation in the hippocampus of kindled rats. Eur J Neurosci 2003; 18:820-8. [PMID: 12925008 DOI: 10.1046/j.1460-9568.2003.02815.x] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Adenosine is a neuromodulator that has been proposed to be a major endogenous anticonvulsant acting via A1 receptors. We tested if implementation of kindling through stimulation of the amygdala affected A1 receptor-mediated neuromodulation in hippocampal slices taken from rats 4 weeks after the last stage 5 seizure. The A1 receptor agonist, N6-cyclopentyladenosine (CPA) (6-100 nm), inhibited field excitatory postsynaptic potential (fEPSP) slope with an EC50 of 19.1-19.5 nm in control and sham-operated rats, but was less potent in kindled rats (EC50 = 42.7 nm). This might result from a decreased number of A1 receptors in hippocampal nerve terminal membranes, because A1 receptor immunoreactivity decreased by 28 +/- 3% and the binding density of the A1 receptor agonist [3H]R-PIA decreased from 1702 +/- 64 to 962 +/- 78 fmol/mg protein in kindled compared with control rats. The tonic inhibition of hippocampal synaptic transmission by endogenous adenosine was also lower in kindled rats, because A1 receptor blockade with 50 nm 1,3-dipropyl-8-cyclopentyladenosine (DPCPX) enhanced fEPSP slope by 23 +/- 3% and theta-burst-induced long-term potentiation by 94 +/- 4% in control rats but was virtually devoid of effects in kindled rats. The evoked release of adenosine from hippocampal slices or nerve terminals was 56-71% lower in kindled rats probably due to the combined decrease in the capacity of adenosine transporters and decreased release of adenosine 5'-triphosphate (ATP), which was partially compensated by a higher extracellular catabolism of ATP into adenosine in kindled rats. These results indicate that, although adenosine might inhibit the onset of epileptogenesis, once kindling is installed, the efficiency of the adenosine inhibitory system is impaired.
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Affiliation(s)
- Nelson Rebola
- Center for Neuroscience of Coimbra, Institute of Biochemistry, Faculty of Medicine, University of Coimbra, 3004-504 Coimbra, Portugal
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Arosio B, Perlini S, Calabresi C, Tozzi R, Palladini G, Ferrari AU, Vergani C, Annoni G. Adenosine A1 and A2A receptor cross-talk during ageing in the rat myocardium. Exp Gerontol 2003; 38:855-61. [PMID: 12915207 DOI: 10.1016/s0531-5565(03)00095-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Adenosine (Ado), a naturally occurring autacoid, exerts cardioprotective effects against myocardial ischemia and reperfusion injury, through activation of its receptors type 1 (A1) and 2A (A2A). Since ageing involves a complex change in these effects, we evaluated A1 and A2A gene expression in left (LV) and right ventricle (RV) from 2-, 5-, 12-, and 21-month-old Sprague-Dawley rats. LV end-diastolic (EDD) and end-systolic (ESD) internal dimensions (mm) and LV fractional shortening (FS, %) were measured by M-mode echocardiography. Senescence was associated with a reduction in FS (42+/-1, 38+/-2, 39+/-2 and 35+/-2, in 2-, 5-, 12- and 21-month-old rats; p<0.02) and increases in EDD (7.5+/-0.2, 8.1+/-0.2, 8.5+/-0.2 and 8.8+/-0.2; p<0.001) and ESD (4.2+/-0.1, 4.4+/-0.2, 4.7+/-0.2 and 5.1+/-0.2; p=0.002). Ado A1 mRNA levels were highest in 12 and 21-month-old animals in both ventricles (LV: p<0.001; RV: p=0.001). By contrast, Ado A2A gene expression was lower in the aged LV (p<0.001), but higher in the aged RV (p<0.001). These modifications of Ado receptor gene expression and especially the increase in A1 receptor mRNA may partially explain the stronger antiadrenergic effects of Ado in the senescent heart.
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Affiliation(s)
- Beatrice Arosio
- Department of Internal Medicine and Gerontology, Ospedale Maggiore IRCCS, Cattedra di Geron. e Geriatria, Via Pace 9, 20122 Milan, Italy
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Headrick JP, Willems L, Ashton KJ, Holmgren K, Peart J, Matherne GP. Ischaemic tolerance in aged mouse myocardium: the role of adenosine and effects of A1 adenosine receptor overexpression. J Physiol 2003; 549:823-33. [PMID: 12717009 PMCID: PMC2342972 DOI: 10.1113/jphysiol.2003.041541] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
The genesis of the ischaemia intolerant phenotype in aged myocardium is poorly understood. We tested the hypothesis that impaired adenosine-mediated protection contributes to ischaemic intolerance, and examined whether this is countered by A1 adenosine receptor (A1AR) overexpression. Responses to 20 min ischaemia and 45 min reperfusion were assessed in perfused hearts from young (2-4 months) and moderately aged (16-18 months) mice. Post-ischaemic contractility was impaired by ageing with elevated ventricular diastolic (32 +/- 2 vs. 18 +/- 2 mmHg in young) and reduced developed (37 +/- 3 vs. 83 +/- 6 mmHg in young) pressures. Lactate dehydrogenase (LDH) loss was exaggerated (27 +/- 2 vs. 16 +/- 2 IU g-1 in young) whereas the incidence of tachyarrhythmias was similar in young (15 +/- 1 %) and aged hearts (16 +/- 1 %). Functional analysis confirmed equipotent effects of 50 micro M adenosine at A1 and A2 receptors in young and aged hearts. Nonetheless, while 50 micro M adenosine improved diastolic (5 +/- 1 mmHg) and developed pressures (134 +/- 7 mmHg) and LDH loss (6 +/- 2 IU g-1) in young hearts, it did not alter these variables in the aged group. Adenosine did attenuate arrhythmogenesis for both ages (to ~10 %). In contrast to adenosine, 50 micro M diazoxide reduced ischaemic damage and arrhythmogenesis for both ages. Contractile and anti-necrotic effects of adenosine were limited by 100 micro M 5-hydroxydecanoate (5-HD) and 3 micro M chelerythrine. Anti-arrhythmic effects were limited by 5-HD but not chelerythrine. Non-selective (100 micro M 8-sulfophenyltheophylline) and A1-selective (150 nM 8-cyclopentyl-1,3-dipropylxanthine) adenosine receptor antagonism impaired ischaemic tolerance in young but not aged hearts. Quantitative real-time PCR and radioligand analysis indicated that impaired protection is unrelated to changes in A1AR mRNA transcription, or receptor density (~8 fmol mg-1 protein in both age groups). However, A1AR overexpression improved tolerance for both ages, restoring adenosine-mediated protection. These data reveal impaired protection via exogenous and endogenous adenosine contributes to ischaemic intolerance with ageing. This is independent of A1AR expression, and involves ineffective activation of a 5-HD-/diazoxide-sensitive process. The effects of A1AR overexpression indicate that the age-related failure in signalling can be overcome.
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Affiliation(s)
- John P Headrick
- Heart Foundation Research Centre, School of Health Science, Griffith University, Southport, QLD 4217, Australia.
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