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Reich N, Mannino M, Kotler S. Using caffeine as a chemical means to induce flow states. Neurosci Biobehav Rev 2024; 159:105577. [PMID: 38331128 DOI: 10.1016/j.neubiorev.2024.105577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 02/01/2024] [Accepted: 02/04/2024] [Indexed: 02/10/2024]
Abstract
Flow is an intrinsically rewarding state characterised by positive affect and total task absorption. Because cognitive and physical performance are optimal in flow, chemical means to facilitate this state are appealing. Caffeine, a non-selective adenosine receptor antagonist, has been emphasized as a potential flow-inducer. Thus, we review the psychological and biological effects of caffeine that, conceptually, enhance flow. Caffeine may facilitate flow through various effects, including: i) upregulation of dopamine D1/D2 receptor affinity in reward-associated brain areas, leading to greater energetic arousal and 'wanting'; ii) protection of dopaminergic neurons; iii) increases in norepinephrine release and alertness, which offset sleep-deprivation and hypoarousal; iv) heightening of parasympathetic high frequency heart rate variability, resulting in improved cortical stress appraisal, v) modification of striatal endocannabinoid-CB1 receptor-signalling, leading to enhanced stress tolerance; and vi) changes in brain network activity in favour of executive function and flow. We also discuss the application of caffeine to treat attention deficit hyperactivity disorder and caveats. We hope to inspire studies assessing the use of caffeine to induce flow.
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Affiliation(s)
- Niklas Reich
- Faculty of Health and Medicine, Biomedical & Life Sciences Division, Lancaster University, Lancaster LA1 4YQ, UK; The ALBORADA Drug Discovery Institute, University of Cambridge, Island Research Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0AH, UK.
| | - Michael Mannino
- Flow Research Collective, USA; Miami Dade College, Miami, FL, USA
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Lummertz Magenis M, Souza de Marcos P, Paganini Damiani A, Ricardo Cantareli da Silva A, Martins Longaretti L, Bahia Franca I, Da Silva J, Rodrigues Boeck C, Moraes de Andrade V. Genotoxic effects of caffeine in female mice exposed during pregnancy and lactation period and their offspring. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART C, TOXICOLOGY AND CARCINOGENESIS 2023; 41:36-60. [PMID: 37243358 DOI: 10.1080/26896583.2023.2213613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Caffeine is a widely consumed substance, and there is a discussion about its effects when ingested by women during pregnancy and lactation. We aimed to identify the genotoxic effects of caffeine in female mice that consumed it during pregnancy and lactation periods and its consequences in their offspring. Thirty-six couples of Swiss mice received water or caffeine (0.3 and 1.0 mg/mL) treatment during pregnancy and lactation. The male and female offspring were divided into 12 groups according to the treatment administered to the female mice. Genotoxicity was assessed using the comet assay and the micronucleus test. Both doses of caffeine showed genotoxic effects in pregnant and lactating mice groups compared to groups not administered caffeine. In relation to offspring, it can be observed that females and males of the offspring had low weight in early life. In both female and male offspring, genotoxicity was detected in the blood, liver, and kidney tissues. Thus, from the present study, we can suggest that the caffeine consumed by female mice during the periods of pregnancy and lactation led to genotoxic effects in their offspring.
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Affiliation(s)
- Marina Lummertz Magenis
- Laboratory of Translational Biomedicine, Graduate Program of Health Sciences, University of Southern Santa Catarina, Criciúma, Santa Catarina, Brazil
| | - Pamela Souza de Marcos
- Laboratory of Translational Biomedicine, Graduate Program of Health Sciences, University of Southern Santa Catarina, Criciúma, Santa Catarina, Brazil
| | - Adriani Paganini Damiani
- Laboratory of Translational Biomedicine, Graduate Program of Health Sciences, University of Southern Santa Catarina, Criciúma, Santa Catarina, Brazil
| | - Anderson Ricardo Cantareli da Silva
- Laboratory of Translational Biomedicine, Graduate Program of Health Sciences, University of Southern Santa Catarina, Criciúma, Santa Catarina, Brazil
| | - Luiza Martins Longaretti
- Laboratory of Translational Biomedicine, Graduate Program of Health Sciences, University of Southern Santa Catarina, Criciúma, Santa Catarina, Brazil
| | - Ive Bahia Franca
- Laboratory of Translational Biomedicine, Graduate Program of Health Sciences, University of Southern Santa Catarina, Criciúma, Santa Catarina, Brazil
| | - Juliana Da Silva
- Laboratory of Genetic Toxicology, Lutheran University of Brazil, Canoas, Rio Grande do Sul, Brazil
- La Salle University, Canoas, Rio Grande do Sul, Brazil
| | - Carina Rodrigues Boeck
- Graduate Program in Nanosciences, Master Degree in Health and Life Science, Franciscan University, Santa Maria, Rio Grande do Sul, Brazil
| | - Vanessa Moraes de Andrade
- Laboratory of Translational Biomedicine, Graduate Program of Health Sciences, University of Southern Santa Catarina, Criciúma, Santa Catarina, Brazil
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Lin YS, Weibel J, Landolt HP, Santini F, Slawik H, Borgwardt S, Cajochen C, Reichert CF. Brain activity during a working memory task after daily caffeine intake and caffeine withdrawal: a randomized double-blind placebo-controlled trial. Sci Rep 2023; 13:1002. [PMID: 36653409 PMCID: PMC9849460 DOI: 10.1038/s41598-022-26808-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Accepted: 12/20/2022] [Indexed: 01/19/2023] Open
Abstract
Acute caffeine intake has been found to increase working memory (WM)-related brain activity in healthy adults without improving behavioral performances. The impact of daily caffeine intake-a ritual shared by 80% of the population worldwide-and of its discontinuation on working memory and its neural correlates remained unknown. In this double-blind, randomized, crossover study, we examined working memory functions in 20 young healthy non-smokers (age: 26.4 ± 4.0 years; body mass index: 22.7 ± 1.4 kg/m2; and habitual caffeine intake: 474.1 ± 107.5 mg/day) in a 10-day caffeine (150 mg × 3 times/day), a 10-day placebo (3 times/day), and a withdrawal condition (9-day caffeine followed by 1-day placebo). Throughout the 10th day of each condition, participants performed four times a working memory task (N-Back, comprising 3- and 0-back), and task-related blood-oxygen-level-dependent (BOLD) activity was measured in the last session with functional magnetic resonance imaging. Compared to placebo, participants showed a higher error rate and a longer reaction time in 3- against 0-back trials in the caffeine condition; also, in the withdrawal condition we observed a higher error rate compared to placebo. However, task-related BOLD activity, i.e., an increased attention network and decreased default mode network activity in 3- versus 0-back, did not show significant differences among three conditions. Interestingly, irrespective of 3- or 0-back, BOLD activity was reduced in the right hippocampus in the caffeine condition compared to placebo. Adding to the earlier evidence showing increasing cerebral metabolic demands for WM function after acute caffeine intake, our data suggest that such demands might be impeded over daily intake and therefore result in a worse performance. Finally, the reduced hippocampal activity may reflect caffeine-associated hippocampal grey matter plasticity reported in the previous analysis. The findings of this study reveal an adapted neurocognitive response to daily caffeine exposure and highlight the importance of classifying impacts of caffeine on clinical and healthy populations.
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Affiliation(s)
- Yu-Shiuan Lin
- Centre for Chronobiology, University Psychiatric Clinics Basel, Wilhelm-Klein Strasse 27, 4002, Basel, Switzerland. .,Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland. .,Neuropsychiatry and Brain Imaging, Psychiatric Hospital of the University of Basel, Basel, Switzerland.
| | - Janine Weibel
- Centre for Chronobiology, University Psychiatric Clinics Basel, Wilhelm-Klein Strasse 27, 4002, Basel, Switzerland.,Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland
| | - Hans-Peter Landolt
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland.,Sleep and Health Zurich, University Center of Competence, University of Zurich, Zurich, Switzerland
| | - Francesco Santini
- Division of Radiological Physics, Department of Radiology, University Hospital Basel, Basel, Switzerland.,Department of Biomedical Engineering, University of Basel, Basel, Switzerland
| | - Helen Slawik
- Centre for Chronobiology, University Psychiatric Clinics Basel, Wilhelm-Klein Strasse 27, 4002, Basel, Switzerland.,Clinical Sleep Laboratory, Psychiatric Hospital of the University of Basel, Basel, Switzerland
| | - Stefan Borgwardt
- Neuropsychiatry and Brain Imaging, Psychiatric Hospital of the University of Basel, Basel, Switzerland
| | - Christian Cajochen
- Centre for Chronobiology, University Psychiatric Clinics Basel, Wilhelm-Klein Strasse 27, 4002, Basel, Switzerland. .,Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland.
| | - Carolin Franziska Reichert
- Centre for Chronobiology, University Psychiatric Clinics Basel, Wilhelm-Klein Strasse 27, 4002, Basel, Switzerland.,Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland
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Peng SL, Chu LWL, Su FY. Cerebral hemodynamic response to caffeine: effect of dietary caffeine consumption. NMR IN BIOMEDICINE 2022; 35:e4727. [PMID: 35285102 DOI: 10.1002/nbm.4727] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 02/14/2022] [Accepted: 03/06/2022] [Indexed: 06/14/2023]
Abstract
Caffeine has a significant effect on cerebrovascular systems, and the dual action of caffeine on both neural and vascular responses leads to concerns for the interpretation of blood oxygenation level-dependent (BOLD) functional MRI. However, potential differences in the brain response to caffeine with regard to consumption habits have not been fully elucidated, as BOLD responses may vary with the dietary caffeine consumption history. The main aim of this study was to characterize the acute effect of caffeine on cerebral hemodynamic responses in participants with different patterns of caffeine consumption habits. Fifteen non-habitual and 11 habitual volunteers were included in this study. The cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) to the breath-hold challenge were measured before and after 200 mg caffeine administration. The non-habitual individuals exhibited a pattern of progressive reduction in CBF with time. The CVR was diminished in the caffeinated condition (P < 0.05). In the habitual group, the pattern of CBF decrease was smaller and homogeneous across the brain, and reached steady state rapidly. The CVR was not affected in the presence of caffeine (P > 0.05). Our results demonstrated that the cerebral hemodynamic response to caffeine was subject to the habitual consumption patterns of the participants. The compromised CVR following caffeine administration in the non-habitual group may partially explain the suppressed BOLD response to a visual stimulation in low-caffeine-level users.
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Affiliation(s)
- Shin-Lei Peng
- Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan
| | - Lok Wang Lauren Chu
- Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan
| | - Feng-Yi Su
- Department of Medical Imaging, China Medical University Hospital, Taichung, Taiwan
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Magenis ML, Damiani AP, Franca IB, de Marcos PS, Effting PS, Muller AP, de Bem Silveira G, Borges Correa MEA, Medeiros EB, Silveira PCL, Budni J, Boeck CR, de Andrade VM. Behavioral, genetic and biochemical changes in the brain of the offspring of female mice treated with caffeine during pregnancy and lactation. Reprod Toxicol 2022; 112:119-135. [PMID: 35868513 DOI: 10.1016/j.reprotox.2022.07.005] [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: 01/17/2022] [Revised: 07/07/2022] [Accepted: 07/16/2022] [Indexed: 11/17/2022]
Abstract
The intrauterine environment is a critical location for exposure to exogenous and endogenous factors that trigger metabolic changes through fetal programming. Among the external factors, chemical compounds stand out, which include caffeine, since its consumption is common among women, including during pregnancy. Thereby, the aim of the present study was to evaluate the behavioral, genetic, and biochemical parameters in the offspring of female mice treated with caffeine during pregnancy and lactation. Swiss female mice (60 days old) received tap water or caffeine at 0.3 or 1.0 mg/mL during copulation (7 days), pregnancy (21 days) and lactation (21 days). After the end of the lactation period, the offspring were divided into groups (water, caffeine 0.3 or 1.0 mg/mL) with 20 animals (10 animals aged 30 days and 10 animals aged 60 days per group per sex). Initially, the offspring were submitted to behavioral tasks and then euthanized for genetic and biochemical analysis in the brain (cortex, striatum, and hippocampus). Behavioral changes in memory, depression, and anxiety were observed in the offspring: 30-day-old female offspring at 1.0 mg /mL dose presented anxiogenic behavior and male offspring the 0.3 mg/mL dose at 30 days of age did not alter long-term memory. Furthermore, an increase in DNA damage and oxidative stress in the brain were observed in the offspring of both sexes. Furthermore, there were changes in Ape-1, BAX, and Bcl-2 in the female offspring hippocampus at 30 days of life. Thus, with this study, we can suggest genotoxicity, oxidative stress, and behavioral changes caused by caffeine during pregnancy and lactation in the offspring that were not treated directly, but received through their mothers; thus, it is important to raise awareness regarding caffeine consumption among pregnant and lactating females.
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Affiliation(s)
- Marina Lummertz Magenis
- Laboratory of Translational Biomedicine, Graduate Program of Health Sciences, University of Southern Santa Catarina - UNESC, Criciúma, SC, Brazil
| | - Adriani Paganini Damiani
- Laboratory of Translational Biomedicine, Graduate Program of Health Sciences, University of Southern Santa Catarina - UNESC, Criciúma, SC, Brazil
| | - Ive Bahia Franca
- Laboratory of Translational Biomedicine, Graduate Program of Health Sciences, University of Southern Santa Catarina - UNESC, Criciúma, SC, Brazil
| | - Pamela Souza de Marcos
- Laboratory of Translational Biomedicine, Graduate Program of Health Sciences, University of Southern Santa Catarina - UNESC, Criciúma, SC, Brazil
| | - Pauline Souza Effting
- Laboratory of Translational Biomedicine, Graduate Program of Health Sciences, University of Southern Santa Catarina - UNESC, Criciúma, SC, Brazil
| | - Alexandre Pastoris Muller
- Laboratory of Translational Biomedicine, Graduate Program of Health Sciences, University of Southern Santa Catarina - UNESC, Criciúma, SC, Brazil
| | - Gustavo de Bem Silveira
- Laboratory of Experimental Pathophysiology, Graduate Program of Health Sciences, University of Southern Santa Catarina - UNESC, Criciúma, SC, Brazil
| | - Maria Eduarda Anastácio Borges Correa
- Laboratory of Experimental Pathophysiology, Graduate Program of Health Sciences, University of Southern Santa Catarina - UNESC, Criciúma, SC, Brazil
| | - Eduarda Behenck Medeiros
- Laboratory of Experimental Neurology, Graduate Program of Health Sciences, University of Southern Santa Catarina - UNESC, Criciúma, SC, Brazil
| | - Paulo Cesar Lock Silveira
- Laboratory of Experimental Pathophysiology, Graduate Program of Health Sciences, University of Southern Santa Catarina - UNESC, Criciúma, SC, Brazil
| | - Josiane Budni
- Laboratory of Experimental Neurology, Graduate Program of Health Sciences, University of Southern Santa Catarina - UNESC, Criciúma, SC, Brazil
| | - Carina Rodrigues Boeck
- Graduate Program in Nanosciences, Franciscan University Center - UNIFRA, Santa Maria, RS, Brazil
| | - Vanessa Moraes de Andrade
- Laboratory of Translational Biomedicine, Graduate Program of Health Sciences, University of Southern Santa Catarina - UNESC, Criciúma, SC, Brazil.
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Effects of Postnatal Caffeine Exposure on Absence Epilepsy and Comorbid Depression: Results of a Study in WAG/Rij Rats. Brain Sci 2022; 12:brainsci12030361. [PMID: 35326317 PMCID: PMC8946037 DOI: 10.3390/brainsci12030361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 03/03/2022] [Accepted: 03/06/2022] [Indexed: 02/01/2023] Open
Abstract
The present study aims to investigate effect of early caffeine exposure on epileptogenesis and occurrence of absence seizures and comorbid depression in adulthood. For this purpose, Wistar Albino Glaxo from Rijswijk (WAG/Rij) rats were enrolled in a control and two experimental groups on the 7th day after the delivery. The rats in experimental groups received either 10 or 20 mg/kg caffeine subcutaneously while animals in control group had subcutaneous injections of 0.9% saline. The injections started at postnatal day 7 (PND7) and were continued each day for 5 days. At 6–7 months of age, electroencephalogram (EEG) recordings and behavioral recordings in the forced swimming test, sucrose consumption/preference test and locomotor activity test were carried out. At 6 months of age, 10 mg/kg and 20 mg/kg caffeine-treated WAG/Rij rats showed increased immobility latency and active swimming duration in forced swimming test when compared with the untreated controls. In addition, 20 mg/kg caffeine treatment decreased immobility time. In sucrose preference/consumption tests, WAG/Rij rats in 10 mg/kg caffeine group demonstrated higher sucrose consumption and preference compared to untreated controls. The rats treated with 20 mg/kg caffeine showed higher sucrose preference compared to control rats. The exploratory activity of rats in the 10 mg/kg caffeine-treated group was found to be higher than in the 20 mg/kg caffeine-treated and control groups in the locomotor activity test. At 7 months of age, caffeine-treated animals showed a decreased spike-wave discharge (SWD) number compared to the control animals. These results indicate that postnatal caffeine treatment may decrease the number of seizure and depression-like behaviors in WAG/Rij rats in later life. Caffeine blockade of adenosine receptors during the early developmental period may have beneficial effects in reducing seizure frequency and depression-like behaviors in WAG/Rij rat model.
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Bourgeois-Vionnet J, Ryvlin P, Elsensohn MH, Michel V, Valton L, Derambure P, Frazzini V, Hirsch E, Maillard L, Bartolomei F, Biberon J, Petit J, Biraben A, Crespel A, Thomas P, Lemesle-Martin M, Convers P, Leclercq M, Boulogne S, Roy P, Rheims S. Coffee consumption and seizure frequency in patients with drug-resistant focal epilepsy. Epilepsy Behav 2022; 126:108486. [PMID: 34929474 DOI: 10.1016/j.yebeh.2021.108486] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 11/28/2021] [Accepted: 11/29/2021] [Indexed: 11/03/2022]
Abstract
OBJECTIVE To assess the relation between coffee consumption and seizure frequency in patients with drug-resistant focal epilepsy. METHODS Cross-sectional analysis of data collected in the SAVE study, which included patients with drug-resistant focal epilepsy during long-term EEG monitoring. Patients in whom both coffee consumption and data about seizure frequency, including focal to bilateral tonic-clonic seizures (FBTCS), were available were selected. Coffee consumption was collected using a standardized self-report questionnaire and classified into four groups: none, rare (from less than 1 cup/week to up 3 cups/week), moderate (from 4 cups/week to 3 cups/day), and high (more than 4 cups/day). RESULTS Six hundred and nineteen patients were included. There was no relation between coffee consumption and total seizure frequency (p = 0.902). In contrast, the number of FBTCS reported over the past year was significantly associated with usual coffee consumption (p = 0.029). Specifically, number of FBCTS in patients who reported moderate coffee consumption was lower than in others. In comparison with patients with moderate coffee consumption, the odds ratio (95%CI) for reporting at least 1 FBTCS per year was 1.6 (1.03-2.49) in patients who never take coffee, 1.62 (1.02-2.57) in those with rare consumption and 2.05 (1.24-3.4) in those with high consumption. Multiple ordinal logistic regression showed a trend toward an association between coffee consumption and number of FBTCS (p = 0.08). CONCLUSIONS AND RELEVANCE Our data suggest that effect of coffee consumption on seizures might depend on dose with potential benefits on FBTCS frequency at moderate doses. These results will have to be confirmed by prospective studies.
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Affiliation(s)
- Julie Bourgeois-Vionnet
- Department of Functional Neurology and Epileptology, Hospices Civils de Lyon and University of Lyon, Lyon, France
| | - Philippe Ryvlin
- Department of Clinical Neurosciences, Centre Hospitalo-Universitaire Vaudois, Lausanne, Switzerland
| | - Mad-Hélénie Elsensohn
- Lyon University, Lyon, France; Équipe Biostatistique Santé, Laboratoire de Biométrie et Biologie Évolutive, CNRS UMR 5558, Villeurbanne, France; Service de Biostatistique-Bioinformatique, Pôle Santé Publique, Hospices Civils de Lyon, Lyon, France
| | | | - Luc Valton
- Clinical Neurophysiology, Department of Neurology, University Hospital of Toulouse, CerCO CNRS UMR 5549, University of Toulouse, France
| | - Philippe Derambure
- Department of Clinical Neurophysiology, Lille University Medical Center, EA 1046, University of Lille 2, France
| | - Valerio Frazzini
- Epileptology Unit, Assistance Publique-Hôpitaux de Paris, Groupe hospitalier Pitié-Salpêtrière and Brain and Spine Institute (ICM; INSERM UMRS1127, CNRS UMR7225, UPMC University Paris 06), Paris, France
| | - Edouard Hirsch
- Department of Neurology, University Hospital of Strasbourg, Strasbourg, France
| | - Louis Maillard
- Neurology Department, University Hospital of Nancy, Nancy, France
| | - Fabrice Bartolomei
- Clinical Neurophysiology and Epileptology Department, Timone Hospital, Marseille, France
| | - Julien Biberon
- Department of Clinical Neurophysiology, INSERM U930, University Hospital of Tours, Tours, France
| | - Jerôme Petit
- La Teppe Epilepsy Center, Tain l'Hermitage, France
| | - Arnaud Biraben
- Department of Neurology, University Hospital of Rennes, Rennes, France
| | | | - Pierre Thomas
- Neurology Department University Hospitals of Nice, Nice, France
| | | | - Philippe Convers
- Department of Neurology, University Hospital of Saint-Etienne, Saint-Etienne, France
| | - Mathilde Leclercq
- Department of Functional Neurology and Epileptology, Hospices Civils de Lyon and University of Lyon, Lyon, France
| | - Sébastien Boulogne
- Department of Functional Neurology and Epileptology, Hospices Civils de Lyon and University of Lyon, Lyon, France; Lyon's Neuroscience Research Center, INSERM U1028 / CNRS UMR 5292 and Lyon 1 University, Lyon, France
| | - Pascal Roy
- Lyon University, Lyon, France; Équipe Biostatistique Santé, Laboratoire de Biométrie et Biologie Évolutive, CNRS UMR 5558, Villeurbanne, France; Service de Biostatistique-Bioinformatique, Pôle Santé Publique, Hospices Civils de Lyon, Lyon, France
| | - Sylvain Rheims
- Department of Functional Neurology and Epileptology, Hospices Civils de Lyon and University of Lyon, Lyon, France; Lyon's Neuroscience Research Center, INSERM U1028 / CNRS UMR 5292 and Lyon 1 University, Lyon, France; Epilepsy Institute, Lyon, France.
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Schamne JC, Ressetti JC, Bertuzzi R, Okuno NM, Lima-Silva AE. Acute Caffeine Intake Reduces Perceived Exertion But Not Muscle Pain during Moderate Intensity Cycling Exercise in Women with Fibromyalgia. J Am Coll Nutr 2021; 41:720-727. [PMID: 34383607 DOI: 10.1080/07315724.2021.1958102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
OBJECTIVE Exacerbated perceived exertion and muscle pain responses during exercise might limit physical activity practice in fibromyalgia patients. Thus, nutritional strategies that can reduce perceived exertion and muscle pain during exercise in fibromyalgia patients would be useful. The purpose of this study was to investigate the effects of acute caffeine intake on the perceptions of exertion and muscle pain during a moderate intensity exercise in women with fibromyalgia.Method: Using a randomized, double-blinded, placebo-controlled and crossover experimental design, eleven sedentary women diagnosed with fibromyalgia (age: 44.6 ± 10.5 years; body mass index: 28.5 ± 4.5 kg.m-2) ingested a capsule containing either caffeine (5 mg per kg of body mass) or cellulose (placebo), 60 minutes before performing a 30-minute constant-load cycling exercise, with work rate fixed at 50% of their individual peak workload attained in an incremental exercise test. Ratings of perceived leg muscle pain and perceived exertion were assessed every 5 minutes of exercise.Results: The perceived leg muscle pain was similar (F(1,10) = 1.18, p = 0.30, ŋ2 = 0.11) between caffeine (2.1 ± 1.2 arbitrary units) and placebo conditions (2.2 ± 0.9 arbitrary units). The perceived exertion, however, was on average 8 ± 6% lower (F(1,10) = 12.13; p = 0.006; ŋ2 = 0.55) during exercise in the caffeine condition (12.4 ± 1.3 arbitrary units) than in the placebo condition (13.1 ± 1.1 arbitrary units).Conclusions: These findings indicate that acute caffeine intake could be an attractive strategy to attenuate the exacerbated perceived exertion of fibromyalgia patients during moderate intensity exercise.
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Affiliation(s)
- Julio Cezar Schamne
- Human Performance Research Group, Academic Department of Physical Education, Federal University of Technology - Parana (UTFPR), Curitiba, Brazil.,Department of Physical Education, State University of Ponta Grossa (UEPG), Ponta Grossa, Brazil
| | - Juliana Campos Ressetti
- Department of Physical Education, State University of Ponta Grossa (UEPG), Ponta Grossa, Brazil
| | - Romulo Bertuzzi
- Endurance Performance Research Group (GEDAE-USP), University of São Paulo, São Paulo, Brazil
| | - Nilo Massaru Okuno
- Department of Physical Education, State University of Ponta Grossa (UEPG), Ponta Grossa, Brazil
| | - Adriano Eduardo Lima-Silva
- Human Performance Research Group, Academic Department of Physical Education, Federal University of Technology - Parana (UTFPR), Curitiba, Brazil
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Vu AT, Feinberg DA. The Role of Cerebral Metabolism in Improving Time Pressured Decisions. Front Psychol 2021; 12:690198. [PMID: 34354635 PMCID: PMC8329240 DOI: 10.3389/fpsyg.2021.690198] [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: 04/02/2021] [Accepted: 06/14/2021] [Indexed: 11/13/2022] Open
Abstract
Speed-accuracy tradeoff (SAT) theory dictates that decisions can be made more quickly by sacrificing accuracy. Here we investigate whether the human brain can operate in a brief metabolic overdrive to overcome SAT and successfully make decisions requiring both high levels of speed and accuracy. In the context of BOLD fMRI we expect “a brief metabolic overdrive” to involve an increase in cerebral oxygen metabolism prior to increased cerebral blood flow–a phenomenon known as the “initial dip” which results from a sudden drop in oxyhemoglobin in perfusing blood. Human subjects performed a motion discrimination task consisting of different difficulties while emphasizing either accuracy (i.e., without time pressure) or both speed and accuracy (i.e., with time pressure). Using simultaneous multi-slice fMRI, for very fast (333 ms) measurement of whole brain BOLD activity, revealed two modes of physiological overdrive responses when subjects emphasized both speed and accuracy. The majority of subjects exhibited the hypothesized enhancement of initial dip amplitude in posterior visual cortex (PVC) with the size of the enhancement significantly correlated with improvement in behavioral performance. For these subjects, the traditionally analyzed post-stimulus overshoot was not affected by task emphasis. These results demonstrate the complexity and variability of the BOLD hemodynamic response. The discovered relationships between BOLD response and behavior were only observed when subjects emphasized both speed and accuracy in more difficult trials suggesting that the brain can perform in a state of metabolic overdrive with enhanced neural processing of sensory information specifically in challenging situations.
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Affiliation(s)
- An Thanh Vu
- San Francisco VA Health Care System, San Francisco, CA, United States.,Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States
| | - David A Feinberg
- Advanced Magnetic Resonance Imaging (MRI) Technologies, Sebastopol, CA, United States.,Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, United States
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Lin YS, Weibel J, Landolt HP, Santini F, Meyer M, Brunmair J, Meier-Menches SM, Gerner C, Borgwardt S, Cajochen C, Reichert C. Daily Caffeine Intake Induces Concentration-Dependent Medial Temporal Plasticity in Humans: A Multimodal Double-Blind Randomized Controlled Trial. Cereb Cortex 2021; 31:3096-3106. [PMID: 33585896 DOI: 10.1093/cercor/bhab005] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 12/25/2020] [Accepted: 12/27/2020] [Indexed: 12/18/2022] Open
Abstract
Caffeine is commonly used to combat high sleep pressure on a daily basis. However, interference with sleep-wake regulation could disturb neural homeostasis and insufficient sleep could lead to alterations in human gray matter. Hence, in this double-blind, randomized, cross-over study, we examined the impact of 10-day caffeine (3 × 150 mg/day) on human gray matter volumes (GMVs) and cerebral blood flow (CBF) by fMRI MP-RAGE and arterial spin-labeling sequences in 20 habitual caffeine consumers, compared with 10-day placebo (3 × 150 mg/day). Sleep pressure was quantified by electroencephalographic slow-wave activity (SWA) in the previous nighttime sleep. Nonparametric voxel-based analyses revealed a significant reduction in GMV in the medial temporal lobe (mTL) after 10 days of caffeine intake compared with 10 days of placebo, voxel-wisely adjusted for CBF considering the decreased perfusion after caffeine intake compared with placebo. Larger GMV reductions were associated with higher individual concentrations of caffeine and paraxanthine. Sleep SWA was, however, neither different between conditions nor associated with caffeine-induced GMV reductions. Therefore, the data do not suggest a link between sleep depth during daily caffeine intake and changes in brain morphology. In conclusion, daily caffeine intake might induce neural plasticity in the mTL depending on individual metabolic processes.
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Affiliation(s)
- Yu-Shiuan Lin
- Centre for Chronobiology, University Psychiatric Clinics, University of Basel, 4002 Basel, Switzerland.,Transfaculty Research Platform, Molecular and Cognitive Neurosciences, University of Basel, 4055 Basel, Switzerland.,Neuropsychiatry and Brain Imaging, University Psychiatric Clinics, University of Basel, 4002 Basel, Switzerland
| | - Janine Weibel
- Centre for Chronobiology, University Psychiatric Clinics, University of Basel, 4002 Basel, Switzerland.,Transfaculty Research Platform, Molecular and Cognitive Neurosciences, University of Basel, 4055 Basel, Switzerland
| | - Hans-Peter Landolt
- Institute of Pharmacology and Toxicology, University of Zurich, 8057 Zurich, Switzerland.,Sleep & Health Zurich, University Center of Competence, University of Zurich, 8091 Zurich, Switzerland
| | - Francesco Santini
- Department of Radiology, Division of Radiological Physics, University Hospital Basel, 4031 Basel, Switzerland.,Department of Biomedical Engineering, University of Basel, 4123 Allschwil, Switzerland
| | - Martin Meyer
- Centre for Chronobiology, University Psychiatric Clinics, University of Basel, 4002 Basel, Switzerland.,Transfaculty Research Platform, Molecular and Cognitive Neurosciences, University of Basel, 4055 Basel, Switzerland.,Clinical Sleep Laboratory, University Psychiatric Clinics, University of Basel, 4002 Basel, Switzerland
| | - Julia Brunmair
- Department of Analytical Chemistry, University of Vienna, 1090 Vienna A, Austria
| | | | - Christopher Gerner
- Department of Analytical Chemistry, University of Vienna, 1090 Vienna A, Austria.,Joint Metabolome Facility, University of Vienna and Medical University of Vienna, 1090 Vienna A, Austria
| | - Stefan Borgwardt
- Neuropsychiatry and Brain Imaging, University Psychiatric Clinics, University of Basel, 4002 Basel, Switzerland
| | - Christian Cajochen
- Centre for Chronobiology, University Psychiatric Clinics, University of Basel, 4002 Basel, Switzerland.,Transfaculty Research Platform, Molecular and Cognitive Neurosciences, University of Basel, 4055 Basel, Switzerland
| | - Carolin Reichert
- Centre for Chronobiology, University Psychiatric Clinics, University of Basel, 4002 Basel, Switzerland.,Transfaculty Research Platform, Molecular and Cognitive Neurosciences, University of Basel, 4055 Basel, Switzerland
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11
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Shih CT, Chiu SC, Peng SL. Caffeine enhances BOLD responses to electrical whisker pad stimulation in rats during alpha-chloralose anaesthesia. Eur J Neurosci 2020; 53:601-610. [PMID: 32926471 DOI: 10.1111/ejn.14968] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Accepted: 09/01/2020] [Indexed: 12/28/2022]
Abstract
By reducing the cerebral blood flow and thereby increasing the resting deoxyhaemoglobin concentration, many human studies have shown that caffeine has a beneficial effect on enhancing the magnitude of blood-oxygenation-level-dependent (BOLD) responses. However, the effect of caffeine on BOLD responses in animals under anaesthesia has not been demonstrated. In this study, we aimed to determine the effect of systemic caffeine administration on BOLD responses in rats under alpha-chloralose. By applying electric whisker pad stimulation to male Sprague-Dawley rats, we performed fMRI measurements before and after the caffeine injection (40 mg/kg, n = 7) or an equivalent volume of saline (n = 6) at 7T. To understand the potential perturbation of animal physiology during stimulation, arterial blood pressure was measured in a separate group of animals (n = 3) outside the scanner. Caffeine significantly decreased baseline BOLD signals (p = .05) due to the increased deoxyhaemoglobin level. Both BOLD responses and t-values in the primary somatosensory cortex were significantly increased (both p < .05). The blood pressure changed insignificantly (p > .05). No significant differences in BOLD responses and t-values were observed in the control condition of saline injection (both p > .05). These findings suggested that, although the cerebral activity was lower under alpha-chloralose anaesthesia, the higher level of deoxygemoglobin at the baseline under the caffeinated condition can benefit the magnitude of BOLD responses in rats. These findings suggest that animal models might serve as potential platforms for further caffeine-related fMRI research studies.
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Affiliation(s)
- Cheng-Ting Shih
- Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan
| | - Shao-Chieh Chiu
- Center for Advanced Molecular Imaging and Translation, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Shin-Lei Peng
- Department of Biomedical Imaging and Radiological Science, China Medical University, Taichung, Taiwan
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12
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Mafra FFP, Macedo MM, Lopes AV, do Nascimento Orphão J, Teixeira CDB, Gattai PP, Boim MA, Torres da Silva R, do Nascimento FD, Bjordal JM, Lopes-Martins RÁB. 904 nm Low-Level Laser Irradiation Decreases Expression of Catabolism-Related Genes in White Adipose Tissue of Wistar Rats: Possible Roles of Laser on Metabolism. PHOTOBIOMODULATION PHOTOMEDICINE AND LASER SURGERY 2019; 38:11-18. [PMID: 31846390 DOI: 10.1089/photob.2018.4609] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Background: Adipose tissue is the main energy storage tissue in the body. Its catabolic and anabolic responses depend on several factors, such as nutritional status, metabolic profile, and hormonal signaling. There are few studies addressing the effects of laser photobiomodulation (PBM) on adipose tissue and results are controversial. Objective: Our purpose was to investigate the metabolic effects of PBM on adipose tissue from Wistar rats supplemented or not with caffeine. Materials and methods: Wistar rats were divided into four groups: control (CTL), laser-treated [CTL (L)], caffeine (CAF), and caffeine+PBM [CAF (L)]. Blood was extracted for quantification of triglyceride and cholesterol levels and white adipose tissues were collected for analysis. We evaluated gene expression in the adipose tissue for the leptin receptor, lipase-sensitive hormone, tumor necrosis factor alpha, and beta adrenergic receptor. Results: We demonstrated that the low-level laser irradiation was able to increase the feed intake of the animals and the relative mass of the adipose tissue in the CTL (L) group compared with CTL. Laser treatment also increases serum triglycerides [CTL = 46.99 ± 5.87; CTL (L) = 57.46 ± 14.38; CAF = 43.98 ± 5.17; and CAF (L) = 56.9 ± 6.12; p = 0.007] and total cholesterol (CTL = 70.62 ± 6.80; CTL (L) = 79.41 ± 13.07; CAF = 71.01 ± 5.52; and CAF (L) = 79.23 ± 6.881; p = 0.003). Conclusions: Laser PBM decreased gene expression of the studied genes in the adipose tissue, indicating that PBM is able to block the catabolic responses of this tissue. Interestingly, the CAF (L) and CAF animals presented the same CLT (L) phenotype, however, without increasing the feed intake and the relative weight of the adipose tissue. The description of these phenomena opens a new perspective for the study of the action of low-level laser in adipose tissue.
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Affiliation(s)
- Fernando F P Mafra
- Technology Research Center, University of Mogi das Cruzes, Mogi das Cruzes, Brazil
| | - Michel M Macedo
- Technology Research Center, University of Mogi das Cruzes, Mogi das Cruzes, Brazil
| | - Arthur Vecchi Lopes
- Technology Research Center, University of Mogi das Cruzes, Mogi das Cruzes, Brazil
| | | | | | - Pedro P Gattai
- Renal Division, Molecular Biology Laboratory, Medicine Department, Federal University of São Paulo, UNIFESP, São Paulo, Brazil
| | - Mirian A Boim
- Renal Division, Molecular Biology Laboratory, Medicine Department, Federal University of São Paulo, UNIFESP, São Paulo, Brazil
| | | | | | - Jan Magnus Bjordal
- Physiotherapy Research Group, Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway
| | - Rodrigo Álvaro Brandão Lopes-Martins
- Laboratory of Biophotonics and Experimental Therapeutics, Institute of Research and Development, University of Vale do Paraíba-UNIVAP, São José dos Campos, São Paulo, Brazil.,Post-Graduate Program in Pharmacology, Faculty of Medical Sciences, State University of Campinas-UNICAMP, Campinas, São Paulo, Brazil
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13
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Borges-Martins VPP, Ferreira DDP, Souto AC, Oliveira Neto JG, Pereira-Figueiredo D, da Costa Calaza K, de Jesus Oliveira K, Manhães AC, de Melo Reis RA, Kubrusly RCC. Caffeine regulates GABA transport via A 1R blockade and cAMP signaling. Neurochem Int 2019; 131:104550. [PMID: 31563462 DOI: 10.1016/j.neuint.2019.104550] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Revised: 09/18/2019] [Accepted: 09/19/2019] [Indexed: 01/06/2023]
Abstract
Caffeine is the most consumed psychostimulant drug in the world, acting as a non-selective antagonist of adenosine receptors A1R and A2AR, which are widely expressed in retinal layers. We have previously shown that caffeine, when administered acutely, acts on A1R to potentiate the NMDA receptor-induced GABA release. Now we asked if long-term caffeine exposure also modifies GABA uptake in the avian retina and which mechanisms are involved in this process. Chicken embryos aged E11 were injected with a single dose of caffeine (30 mg/kg) in the air chamber. Retinas were dissected on E15 for ex vivo neurochemical assays. Our results showed that [3H]-GABA uptake was dependent on Na+ and blocked at 4 °C or by NO-711 and caffeine. This decrease was observed after 60 min of [3H]-GABA uptake assay at E15, which is accompanied by an increase in [3H]-GABA release. Caffeine increased the protein levels of A1R without altering ADORA1 mRNA and was devoid of effects on A2AR density or ADORA2A mRNA levels. The decrease of GABA uptake promoted by caffeine was reverted by A1R activation with N6-cyclohexyl adenosine (CHA) but not by A2AR activation with CGS 21680. Caffeine exposure increased cAMP levels and GAT-1 protein levels, which was evenly expressed between E11-E15. As expected, we observed an increase of GABA containing amacrine cells and processes in the IPL, also, cAMP pathway blockage by H-89 decreased caffeine mediated [3H]-GABA uptake. Our data support the idea that chronic injection of caffeine alters GABA transport via A1R during retinal development and that the cAMP/PKA pathway plays an important role in the regulation of GAT-1 function.
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Affiliation(s)
| | - Danielle Dias Pinto Ferreira
- Laboratório de Doenças Neurodegenerativas, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Arthur Cardoso Souto
- Laboratório de Neurofarmacologia, Departamento de Fisiologia e Farmacologia, Universidade Federal Fluminense, Niterói, Brazil.
| | - Jessika Geisebel Oliveira Neto
- Laboratório de Fisiologia Endócrina e Metabologia, Departamento de Fisiologia e Farmacologia, Universidade Federal Fluminense, Niterói, Brazil.
| | - Danniel Pereira-Figueiredo
- Laboratório de Neurobiologia da Retina, Departmento de Neurobiologia, Instituto de Biologia, Universidade Federal Fluminense, Niterói, Brazil.
| | - Karin da Costa Calaza
- Laboratório de Neurobiologia da Retina, Departmento de Neurobiologia, Instituto de Biologia, Universidade Federal Fluminense, Niterói, Brazil.
| | - Karen de Jesus Oliveira
- Laboratório de Fisiologia Endócrina e Metabologia, Departamento de Fisiologia e Farmacologia, Universidade Federal Fluminense, Niterói, Brazil.
| | - Alex Christian Manhães
- Laboratório de Neurofisiologia, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Ricardo Augusto de Melo Reis
- Laboratório de Neuroquímica, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Regina Célia Cussa Kubrusly
- Laboratório de Neurofarmacologia, Departamento de Fisiologia e Farmacologia, Universidade Federal Fluminense, Niterói, Brazil.
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14
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Peng SL, Chiu H, Wu CY, Huang CW, Chung YH, Shih CT, Shen WC. The effect of caffeine on cerebral metabolism during alpha-chloralose anesthesia differs from isoflurane anesthesia in the rat brain. Psychopharmacology (Berl) 2019; 236:1749-1757. [PMID: 30604185 DOI: 10.1007/s00213-018-5157-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Accepted: 12/19/2018] [Indexed: 10/27/2022]
Abstract
RATIONALE Caffeine is a widely studied psychostimulant, even though its exact effect on brain activity remains to be elucidated. Positron emission tomography (PET) allows studying mechanisms underlying cerebral metabolic responses to caffeine in caffeine-naïve rats. Rodent studies are typically performed under anesthesia. However, the anesthesia may affect neurotransmitter systems targeted by tested drugs. OBJECTIVES The scope of the present study was to address the impairing or enhancing effect of two common anesthetics, alpha-chloralose and isoflurane, on the kinetics of caffeine. METHODS The first group of rats (n = 15) were anesthetized under 1.5% isoflurane anesthesia. The second group of rats (n = 15) were anesthetized under alpha-chloralose (80 mg/kg). These rats received an intravenous injection of saline (n = 5) or of 2.5 mg/kg (n = 5) or 40 mg/kg (n = 5) caffeine for both groups. RESULTS With 2.5 mg/kg or 40 mg/kg caffeine, whole-brain cerebral metabolism was significantly reduced by 17.2% and 17% (both P < 0.01), respectively, under alpha-chloralose anesthesia. However, the lower dose of caffeine (2.5 mg/kg) had a limited effect on brain metabolism, whereas its higher dose (40 mg/kg) produced enhancements in brain metabolism in the striatum, hippocampus, and thalamus (all P < 0.05) under isoflurane anesthesia. CONCLUSION These findings demonstrate significant differences in brain responses to caffeine on the basic of the anesthesia regimen used, which highlights the importance of attention to the anesthetic used when interpreting findings from animal pharmacological studies because of possible interactions between the anesthetic and the drug under study.
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Affiliation(s)
- Shin-Lei Peng
- Department of Biomedical Imaging and Radiological Science, China Medical University, 91 Hsueh-Shih Road, Taichung, 40402, Taiwan.
| | - Han Chiu
- Center for Advanced Molecular Imaging and Translation, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Chun-Yi Wu
- Department of Biomedical Imaging and Radiological Science, China Medical University, 91 Hsueh-Shih Road, Taichung, 40402, Taiwan
| | - Chiun-Wei Huang
- Center for Advanced Molecular Imaging and Translation, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Yi-Hsiu Chung
- Center for Advanced Molecular Imaging and Translation, Chang Gung Memorial Hospital, Taoyuan, Taiwan
| | - Cheng-Ting Shih
- Department of Medical Imaging and Radiological Sciences, Chung Shan Medical University, Taichung, Taiwan
| | - Wu-Chung Shen
- Department of Biomedical Imaging and Radiological Science, China Medical University, 91 Hsueh-Shih Road, Taichung, 40402, Taiwan.,Department of Radiology, China Medical University Hospital, Taichung, Taiwan
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15
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Abstract
PURPOSE OF REVIEW Caffeine is the most widely consumed central nervous stimulant. For people with epilepsy, it is often unclear whether drinking coffee carries a risk of triggering seizures. RECENT FINDINGS The relationship between caffeine, seizures, epilepsy, and anti-seizure drugs is not fully understood. Clinical studies are scarce. In animal models, caffeine can increase seizure susceptibility but can also protect from seizures. Effects seem dose-dependent and are influenced by the duration of intake and the developmental stage at which caffeine exposure started. Caffeine reduces the efficacy of several anti-seizure medications, especially topiramate. It is unclear how these findings, mainly from animal studies, can be translated to the clinical condition. At present, there is no evidence to advise people with epilepsy against the use or overuse of caffeine. Until clinical studies suggest otherwise, caffeine intake should be considered as a factor in achieving and maintaining seizure control in epilepsy.
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16
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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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17
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van Koert RR, Bauer PR, Schuitema I, Sander JW, Visser GH. Caffeine and seizures: A systematic review and quantitative analysis. Epilepsy Behav 2018; 80:37-47. [PMID: 29414557 DOI: 10.1016/j.yebeh.2017.11.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 10/31/2017] [Accepted: 11/01/2017] [Indexed: 01/30/2023]
Abstract
PURPOSE Caffeine is the most commonly used central nervous system (CNS) stimulant. The relationship between caffeine, seizures, epilepsy, and antiepileptic drugs (AEDs) is complex and not fully understood. Case reports suggest that caffeine triggers seizures in susceptible people. Our systematic review reports on the relationship between caffeine, seizures, and drugs in animal and human studies. Quantitative analyses were also done on animal studies regarding the effects of caffeine on AEDs. METHODS PubMed was searched for studies assessing the effects of caffeine on seizure susceptibility, epilepsy, and drug interactions in people and in animal models. To quantify the interaction between AEDs and caffeine, the data of six animal studies were pooled and analyzed using a general linear model univariate analysis or One-way Analysis of Variance (ANOVA). RESULTS In total, 442 items were identified from which we included 105 studies. Caffeine can increase seizure susceptibility and protect from seizures, depending on the dose, administration type (chronic or acute), and the developmental stage at which caffeine exposure started. In animal studies, caffeine decreased the antiepileptic potency of some drugs; this effect was strongest in topiramate. CONCLUSION Preclinical studies suggest that caffeine increases seizure susceptibility. In some cases, chronic use of caffeine may protect against seizures. Caffeine lowers the efficacy of several drugs, especially topiramate. It is unclear how these findings in models can be translated to the clinical condition. Until clinical studies suggest otherwise, caffeine intake should be considered as a factor in achieving and maintaining seizure control in epilepsy.
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Affiliation(s)
- Rick R van Koert
- Health, Medical and Neuropsychology Unit, Institute of Psychology, Leiden University, Leiden, The Netherlands
| | - Prisca R Bauer
- Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, The Netherlands; NIHR University College London Hospitals Biomedical Research Centre, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK
| | - Ilse Schuitema
- Health, Medical and Neuropsychology Unit, Institute of Psychology, Leiden University, Leiden, The Netherlands
| | - Josemir W Sander
- Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, The Netherlands; NIHR University College London Hospitals Biomedical Research Centre, UCL Institute of Neurology, Queen Square, London WC1N 3BG, UK; Chalfont Centre for Epilepsy, Chalfont St Peter, UK.
| | - Gerhard H Visser
- Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, The Netherlands
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18
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Changes of Cerebral and/or Peripheral Adenosine A₁ Receptor and IGF-I Concentrations under Extended Sleep Duration in Rats. Int J Mol Sci 2017; 18:ijms18112439. [PMID: 29149028 PMCID: PMC5713406 DOI: 10.3390/ijms18112439] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 11/10/2017] [Accepted: 11/14/2017] [Indexed: 12/31/2022] Open
Abstract
Extended sleep improves sustained attention and reduces sleep pressure in humans. Downregulation of adenosine A₁ receptor (A₁R) and modulation of the neurotrophic factor insulin growth factor-1 (IGF-I) in brain structures controlling attentional capacities could be involved. In the frontal cortex and hippocampus of rats, we measured adenosine A₁R and IGF-I protein concentrations after photoperiod-induced sleep extension. Two groups of twelve rats were adapted over 14 days to a habitual (CON) 12:12 light-dark (LD) schedule and an extended (EXT) 16:8 LD schedule. IGF-I content was also measured in plasma, liver, and skeletal muscle. In EXT, compared to CON rats, A₁R content in the frontal cortex was significantly lower (p < 0.05), while IGF-I content was higher (p < 0.001), and no significant change was observed in the hippocampus. IGF-I content in plasma and muscle was higher (p < 0.001 and p < 0.01), while it was lower in liver (p < 0.001). The absolute weight and weight gain were higher in EXT rats (p < 0.01). These data suggest that 14 days under a 16:8 LD photoperiod respectively down- and upregulated cortical A₁R and IGF-I levels. This photoperiod induced an anabolic profile with increased weight gain and circulating and muscular IGF-I levels. An extension of sleep duration might favor cerebral and peripheral anabolism, which may help attentional and physical capacities.
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19
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The Role of Adenosine Signaling in Headache: A Review. Brain Sci 2017; 7:brainsci7030030. [PMID: 28335379 PMCID: PMC5366829 DOI: 10.3390/brainsci7030030] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Revised: 03/05/2017] [Accepted: 03/07/2017] [Indexed: 12/18/2022] Open
Abstract
Migraine is the third most prevalent disease on the planet, yet our understanding of its mechanisms and pathophysiology is surprisingly incomplete. Recent studies have built upon decades of evidence that adenosine, a purine nucleoside that can act as a neuromodulator, is involved in pain transmission and sensitization. Clinical evidence and rodent studies have suggested that adenosine signaling also plays a critical role in migraine headache. This is further supported by the widespread use of caffeine, an adenosine receptor antagonist, in several headache treatments. In this review, we highlight evidence that supports the involvement of adenosine signaling in different forms of headache, headache triggers, and basic headache physiology. This evidence supports adenosine A2A receptors as a critical adenosine receptor subtype involved in headache pain. Adenosine A2A receptor signaling may contribute to headache via the modulation of intracellular Cyclic adenosine monophosphate (cAMP) production or 5' AMP-activated protein kinase (AMPK) activity in neurons and glia to affect glutamatergic synaptic transmission within the brainstem. This evidence supports the further study of adenosine signaling in headache and potentially illuminates it as a novel therapeutic target for migraine.
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20
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Atik A, Harding R, De Matteo R, Kondos-Devcic D, Cheong J, Doyle LW, Tolcos M. Caffeine for apnea of prematurity: Effects on the developing brain. Neurotoxicology 2016; 58:94-102. [PMID: 27899304 DOI: 10.1016/j.neuro.2016.11.012] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 11/20/2016] [Accepted: 11/25/2016] [Indexed: 12/20/2022]
Abstract
Caffeine is a methylxanthine that is widely used to treat apnea of prematurity (AOP). In preterm infants, caffeine reduces the duration of respiratory support, improves survival rates and lowers the incidence of cerebral palsy and cognitive delay. There is, however, little evidence relating to the immediate and long-term effects of caffeine on brain development, especially at the cellular and molecular levels. Experimental data are conflicting, with studies showing that caffeine can have either adverse or benefical effects in the developing brain. The aim of this article is to review current understanding of how caffeine ameliorates AOP, the cellular and molecular mechanisms by which caffeine exerts its effects and the effects of caffeine on brain development. A better knowledge of the effects of caffeine on the developing brain at the cellular and/or molecular level is essential in order to understand the basis for the impact of caffeine on postnatal outcome. The studies reviewed here suggest that while caffeine has respiratory benefits for preterm infants, it may have adverse molecular and cellular effects on the developing brain; indeed a majority of experimental studies suggest that regardless of dose or duration of administration, caffeine leads to detrimental changes within the developing brain. Thus there is an urgent need to assess the impact of caffeine, at a range of doses, on the structure and function of the developing brain in preclinical studies, particularly using clinically relevant animal models. Future studies should focus on determining the maximal dose of caffeine that is safe for the preterm brain.
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Affiliation(s)
- Anzari Atik
- Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Richard Harding
- Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Robert De Matteo
- Department of Anatomy and Developmental Biology, Monash University, Clayton, Victoria, Australia
| | - Delphi Kondos-Devcic
- School of Health and Biomedical Sciences, RMIT University, Bundoora, Victoria, Australia
| | - Jeanie Cheong
- Department of Neonatal Services, Royal Women's Hospital, Victorian Infant Brain Studies, Murdoch Children's Research Institute, and Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, Victoria, Australia
| | - Lex W Doyle
- Department of Neonatal Services, Royal Women's Hospital, Victorian Infant Brain Studies, Murdoch Children's Research Institute, and Department of Obstetrics and Gynaecology, University of Melbourne, Melbourne, Victoria, Australia
| | - Mary Tolcos
- School of Health and Biomedical Sciences, RMIT University, Bundoora, Victoria, Australia; The Ritchie Centre, Hudson Institute of Medical Research, Clayton, Victoria, Australia; Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia.
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Beaumont R, Cordery P, Funnell M, Mears S, James L, Watson P. Chronic ingestion of a low dose of caffeine induces tolerance to the performance benefits of caffeine. J Sports Sci 2016; 35:1920-1927. [DOI: 10.1080/02640414.2016.1241421] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Ross Beaumont
- School of Sport, Exercise and Health Sciences, Loughborough University, Leicestershire, UK
| | - Philip Cordery
- School of Sport, Exercise and Health Sciences, Loughborough University, Leicestershire, UK
| | - Mark Funnell
- School of Sport, Exercise and Health Sciences, Loughborough University, Leicestershire, UK
| | - Stephen Mears
- School of Sport, Exercise and Health Sciences, Loughborough University, Leicestershire, UK
| | - Lewis James
- School of Sport, Exercise and Health Sciences, Loughborough University, Leicestershire, UK
| | - Phillip Watson
- Department of Human Physiology and Sports Medicine, Vrije Universiteit Brussel, Brussels, Belgium
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Brito R, Pereira-Figueiredo D, Socodato R, Paes-de-Carvalho R, Calaza KC. Caffeine exposure alters adenosine system and neurochemical markers during retinal development. J Neurochem 2016; 138:557-70. [PMID: 27221759 DOI: 10.1111/jnc.13683] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 05/11/2016] [Accepted: 05/12/2016] [Indexed: 01/18/2023]
Abstract
Evidence points to beneficial properties of caffeine in the adult central nervous system, but teratogenic effects have also been reported. Caffeine exerts most of its effects by antagonizing adenosine receptors, especially A1 and A2A subtypes. In this study, we evaluated the role of caffeine on the expression of components of the adenosinergic system in the developing avian retina and the impact of caffeine exposure upon specific markers for classical neurotransmitter systems. Caffeine exposure (5-30 mg/kg by in ovo injection) to 14-day-old chick embryos increased the expression of A1 receptors and concomitantly decreased A2A adenosine receptors expression after 48 h. Accordingly, caffeine (30 mg/kg) increased [(3) H]-8-cyclopentyl-1,3-dipropylxanthine (A1 antagonist) binding and reduced [(3) H]-ZM241385 (A2A antagonist) binding. The caffeine time-response curve demonstrated a reduction in A1 receptors 6 h after injection, but an increase after 18 and 24 h. In contrast, caffeine exposure increased the expression of A2A receptors from 18 and 24 h. Kinetic assays of [(3) H]-S-(4-nitrobenzyl)-6-thioinosine binding to the equilibrative adenosine transporter ENT1 revealed an increase in Bmax with no changes in Kd , an effect accompanied by an increase in adenosine uptake. Immunohistochemical analysis showed a decrease in retinal content of tyrosine hydroxylase, calbindin and choline acetyltransferase, but not Brn3a, after 48 h of caffeine injection. Furthermore, retinas exposed to caffeine had increased levels of phosphorylated extracellular signal-regulated kinase and cAMP-response element binding protein. Overall, we show an in vivo regulation of the adenosine system, extracellular signal-regulated kinase and cAMP-response element binding protein function and protein expression of specific neurotransmitter systems by caffeine in the developing retina. The beneficial or maleficent effects of caffeine have been demonstrated by the work of different studies. It is known that during animal development, caffeine can exert harmful effects, impairing the correct formation of CNS structures. In this study, we demonstrated cellular and tissue effects of caffeine's administration on developing chick embryo retinas. Those effects include modulation of adenosine receptors (A1 , A2 ) content, increasing in cAMP response element-binding protein (pCREB) and extracellular signal-regulated kinase phosphorylation (pERK), augment of adenosine equilibrative transporter content/activity, and a reduction of some specific cell subpopulations. ENT1, Equilibrative nucleoside transporter 1.
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Affiliation(s)
- Rafael Brito
- Neurobiology of the Retina Laboratory, Department of Neurobiology and Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil.,Laboratory of Cellular Neurobiology, Department of Neurobiology and Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil
| | - Danniel Pereira-Figueiredo
- Neurobiology of the Retina Laboratory, Department of Neurobiology and Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil
| | - Renato Socodato
- Instituto de Investigação e Inovação em Saúde (i3S) and Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto, Porto, Portugal
| | - Roberto Paes-de-Carvalho
- Laboratory of Cellular Neurobiology, Department of Neurobiology and Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil
| | - Karin C Calaza
- Neurobiology of the Retina Laboratory, Department of Neurobiology and Program of Neurosciences, Institute of Biology, Fluminense Federal University, Niterói, Rio de Janeiro, Brazil
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Francikowski J, Baran B, Płachetka-Bożek A, Krzyżowski M, Augustyniak M. Caffeine effects on AdoR mRNA expression in Drosophila melanogaster. Open Life Sci 2016. [DOI: 10.1515/biol-2016-0034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
AbstractIn this study, we aimed to evaluate whether exposure to caffeine in the early stages of development affect AdoR mRNA expression levels in the fruit fly (Drosophila melanogaster) and how this will relate to the developmental success of flies. Adenosine receptors are seen as the most important biochemical targets of caffeine. Simultaneously adenosine signaling orchestrates the development and growth of insects. We demonstrate that AdoR mRNA expression in D. melanogaster is persistent from early stages till imago. Strong alterations in AdoR expression were observed in larvae that had been treated with caffeine. However, after the imaginal molt, the differences in AdoR expression between the insects from all of the test groups evened out despite a wide range of developmental success in the groups. Taken together, these results suggest that caffeine affects the expression of its cellular targets even from the early stages of fruit fly development and thus there is a significantly lower larvae-to-adult survival rate. Moreover, we also proved that the expression of AdoR undergoes a peculiar reset during the maturation of D. melanogaster despite the conditions in which larvae developed.
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Affiliation(s)
- Jacek Francikowski
- 1Department of Animal Physiology and Ecotoxicology, Faculty of Biology and Environmental Protection, University of Silesia, Bankowa 9, 40-007 Katowice, Poland
| | - Bartosz Baran
- 1Department of Animal Physiology and Ecotoxicology, Faculty of Biology and Environmental Protection, University of Silesia, Bankowa 9, 40-007 Katowice, Poland
| | - Anna Płachetka-Bożek
- 1Department of Animal Physiology and Ecotoxicology, Faculty of Biology and Environmental Protection, University of Silesia, Bankowa 9, 40-007 Katowice, Poland
| | - Michał Krzyżowski
- 1Department of Animal Physiology and Ecotoxicology, Faculty of Biology and Environmental Protection, University of Silesia, Bankowa 9, 40-007 Katowice, Poland
| | - Maria Augustyniak
- 1Department of Animal Physiology and Ecotoxicology, Faculty of Biology and Environmental Protection, University of Silesia, Bankowa 9, 40-007 Katowice, Poland
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Nazario LR, Antonioli RJ, Capiotti KM, Hallak JEC, Zuardi AW, Crippa JAS, Bonan CD, da Silva RS. Reprint of "Caffeine protects against memory loss induced by high and non-anxiolytic dose of cannabidiol in adult zebrafish (Danio rerio)". Pharmacol Biochem Behav 2015; 139 Pt B:134-40. [PMID: 26569549 DOI: 10.1016/j.pbb.2015.11.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Revised: 06/03/2015] [Accepted: 06/13/2015] [Indexed: 12/18/2022]
Abstract
Cannabidiol (CBD) has been investigated in a wide spectrum of clinical approaches due to its psychopharmacological properties. CBD has low affinity for cannabinoid neuroreceptors and agonistic properties to 5-HT receptors. An interaction between cannabinoid and purinergic receptor systems has been proposed. The purpose of this study is to evaluate CBD properties on memory behavioral and locomotor parameters and the effects of pre-treatment of adenosine receptor blockers on CBD impacts on memory using adult zebrafish. CBD (0.1, 0.5, 5, and 10mg/kg) was tested in the avoidance inhibitory paradigm and anxiety task. We analyzed the effect of a long-term caffeine pre-treatment (~20mg/L - four months). Also, acute block of adenosine receptors was performed in co-administration with CBD exposure in the memory assessment. CBD promoted an inverted U-shaped dose-response curve in the anxiety task; in the memory assessment, CBD in the dose of 5mg/Kg promoted the strongest effects without interfering with social and aggressive behavior. Caffeine treatment was able to prevent CBD (5mg/kg) effects on memory when CBD was given after the training session. CBD effects on memory were partially prevented by co-treatment with a specific A2A adenosine receptor antagonist when given prior to or after the training session, while CBD effects after the training session were fully prevented by adenosine A1 receptor antagonist. These results indicated that zebrafish have responses to CBD anxiolytic properties that are comparable to other animal models, and high doses changed memory retention in a way dependent on adenosine.
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Affiliation(s)
- Luiza Reali Nazario
- Laboratório de Neuroquímica e Psicofarmacologia, Departamento de Biologia Celular e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul, Avenida Ipiranga, 6681, Caixa Postal 1429, 90619-900 Porto Alegre, RS, Brazil
| | - Régis Junior Antonioli
- Laboratório de Neuroquímica e Psicofarmacologia, Departamento de Biologia Celular e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul, Avenida Ipiranga, 6681, Caixa Postal 1429, 90619-900 Porto Alegre, RS, Brazil
| | - Katiucia Marques Capiotti
- Laboratório de Neuroquímica e Psicofarmacologia, Departamento de Biologia Celular e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul, Avenida Ipiranga, 6681, Caixa Postal 1429, 90619-900 Porto Alegre, RS, Brazil
| | - Jaime Eduardo Cecílio Hallak
- Departamento de Neurociências e Ciências do Comportamento, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Brazil; Instituto Nacional de Ciência e Tecnologia Translacional em Medicina (INCT-TM), 90035-003 Porto Alegre, RS, Brazil
| | - Antonio Waldo Zuardi
- Departamento de Neurociências e Ciências do Comportamento, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Brazil; Instituto Nacional de Ciência e Tecnologia Translacional em Medicina (INCT-TM), 90035-003 Porto Alegre, RS, Brazil
| | - José Alexandre S Crippa
- Departamento de Neurociências e Ciências do Comportamento, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Brazil; Instituto Nacional de Ciência e Tecnologia Translacional em Medicina (INCT-TM), 90035-003 Porto Alegre, RS, Brazil
| | - Carla Denise Bonan
- Laboratório de Neuroquímica e Psicofarmacologia, Departamento de Biologia Celular e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul, Avenida Ipiranga, 6681, Caixa Postal 1429, 90619-900 Porto Alegre, RS, Brazil; Instituto Nacional de Ciência e Tecnologia Translacional em Medicina (INCT-TM), 90035-003 Porto Alegre, RS, Brazil
| | - Rosane Souza da Silva
- Laboratório de Neuroquímica e Psicofarmacologia, Departamento de Biologia Celular e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul, Avenida Ipiranga, 6681, Caixa Postal 1429, 90619-900 Porto Alegre, RS, Brazil; Instituto Nacional de Ciência e Tecnologia Translacional em Medicina (INCT-TM), 90035-003 Porto Alegre, RS, Brazil.
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Kim Y, Elmenhorst D, Weisshaupt A, Wedekind F, Kroll T, McCarley RW, Strecker RE, Bauer A. Chronic sleep restriction induces long-lasting changes in adenosine and noradrenaline receptor density in the rat brain. J Sleep Res 2015; 24:549-558. [PMID: 25900125 PMCID: PMC4583343 DOI: 10.1111/jsr.12300] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Accepted: 03/15/2015] [Indexed: 01/10/2023]
Abstract
Although chronic sleep restriction frequently produces long-lasting behavioural and physiological impairments in humans, the underlying neural mechanisms are unknown. Here we used a rat model of chronic sleep restriction to investigate the role of brain adenosine and noradrenaline systems, known to regulate sleep and wakefulness, respectively. The density of adenosine A1 and A2a receptors and β-adrenergic receptors before, during and following 5 days of sleep restriction was assessed with autoradiography. Rats (n = 48) were sleep-deprived for 18 h day(-1) for 5 consecutive days (SR1-SR5), followed by 3 unrestricted recovery sleep days (R1-R3). Brains were collected at the beginning of the light period, which was immediately after the end of sleep deprivation on sleep restriction days. Chronic sleep restriction increased adenosine A1 receptor density significantly in nine of the 13 brain areas analysed with elevations also observed on R3 (+18 to +32%). In contrast, chronic sleep restriction reduced adenosine A2a receptor density significantly in one of the three brain areas analysed (olfactory tubercle which declined 26-31% from SR1 to R1). A decrease in β-adrenergic receptors density was seen in substantia innominata and ventral pallidum which remained reduced on R3, but no changes were found in the anterior cingulate cortex. These data suggest that chronic sleep restriction can induce long-term changes in the brain adenosine and noradrenaline receptors, which may underlie the long-lasting neurocognitive impairments observed in chronic sleep restriction.
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Affiliation(s)
- Youngsoo Kim
- Department of Psychiatry, VA Boston Healthcare System, Research Service and Harvard Medical School, Brockton, MA, USA
| | - David Elmenhorst
- Department of Psychiatry, VA Boston Healthcare System, Research Service and Harvard Medical School, Brockton, MA, USA
- Institute for Neuroscience and Medicine (INM-2), Forschungszentrum Jülich, Jülich, Germany
| | - Angela Weisshaupt
- Institute for Neuroscience and Medicine (INM-2), Forschungszentrum Jülich, Jülich, Germany
| | - Franziska Wedekind
- Institute for Neuroscience and Medicine (INM-2), Forschungszentrum Jülich, Jülich, Germany
| | - Tina Kroll
- Institute for Neuroscience and Medicine (INM-2), Forschungszentrum Jülich, Jülich, Germany
| | - Robert W McCarley
- Department of Psychiatry, VA Boston Healthcare System, Research Service and Harvard Medical School, Brockton, MA, USA
| | - Robert E Strecker
- Department of Psychiatry, VA Boston Healthcare System, Research Service and Harvard Medical School, Brockton, MA, USA
| | - Andreas Bauer
- Institute for Neuroscience and Medicine (INM-2), Forschungszentrum Jülich, Jülich, Germany
- Neurological Department, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
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26
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Caffeine protects against memory loss induced by high and non-anxiolytic dose of cannabidiol in adult zebrafish (Danio rerio). Pharmacol Biochem Behav 2015; 135:210-6. [DOI: 10.1016/j.pbb.2015.06.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Revised: 06/03/2015] [Accepted: 06/13/2015] [Indexed: 02/02/2023]
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Dodd FL, Kennedy DO, Riby LM, Haskell-Ramsay CF. A double-blind, placebo-controlled study evaluating the effects of caffeine and L-theanine both alone and in combination on cerebral blood flow, cognition and mood. Psychopharmacology (Berl) 2015; 232:2563-76. [PMID: 25761837 PMCID: PMC4480845 DOI: 10.1007/s00213-015-3895-0] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 02/11/2015] [Indexed: 01/09/2023]
Abstract
RATIONALE Evidence suggests interactive effects of the tea components caffeine and L-theanine on behaviour, yet no data exists exploring the impact of the two on cerebral blood flow (CBF). OBJECTIVES The current placebo-controlled, double-blind, counterbalanced, crossover study examined the effects of caffeine and L-theanine on CBF and extended previous cognitive and mood findings by using lower doses than previous studies of a similar methodology, which more closely reflect the ratios present in tea. METHODS Twelve habitual consumers and 12 non-habitual consumers of caffeine each received 75 mg caffeine, 50 mg L-theanine, 75 mg caffeine plus 50 mg L-theanine, and placebo in a counterbalanced order across four separate visits. CBF was measured via near-infrared spectroscopy with cognition and mood assessed at baseline and 30 min post-dose. Salivary caffeine and peripheral haemodynamics were co-monitored. RESULTS Caffeine reduced oxygenated haemoglobin (oxy-Hb), increased deoxygenated haemoglobin (deoxy-Hb), improved performance on attention tasks and increased overall mood ratings. Increases in deoxy-Hb following caffeine were more pronounced in non-consumers. Some evidence for increased deoxy-Hb remained when caffeine was combined with L-theanine, but this effect was attenuated and the effects of caffeine on oxy-Hb, cognition and mood were eradicated. CONCLUSIONS Combining L-theanine with caffeine, at levels and ratios equivalent to one to two cups of tea, eliminated the vasoconstrictive effect and behavioural effects of caffeine. This supports previous findings of an interaction between these substances, despite a lack of effects of L-theanine in isolation. However, at the levels tested here, this did not lead to a positive impact on behaviour.
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Affiliation(s)
- F. L. Dodd
- Brain, Performance and Nutrition Research Centre, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST UK
| | - D. O. Kennedy
- Brain, Performance and Nutrition Research Centre, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST UK
| | - L. M. Riby
- Brain, Performance and Nutrition Research Centre, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST UK
| | - C. F. Haskell-Ramsay
- Brain, Performance and Nutrition Research Centre, Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST UK
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Hohoff C, Garibotto V, Elmenhorst D, Baffa A, Kroll T, Hoffmann A, Schwarte K, Zhang W, Arolt V, Deckert J, Bauer A. Association of adenosine receptor gene polymorphisms and in vivo adenosine A1 receptor binding in the human brain. Neuropsychopharmacology 2014; 39:2989-99. [PMID: 24943643 PMCID: PMC4229568 DOI: 10.1038/npp.2014.150] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 05/13/2014] [Accepted: 05/27/2014] [Indexed: 11/09/2022]
Abstract
Adenosine A1 receptors (A1ARs) and the interacting adenosine A2A receptors are implicated in neurological and psychiatric disorders. Variants within the corresponding genes ADORA1 and ADORA2A were shown associated with pathophysiologic alterations, particularly increased anxiety. It is unknown so far, if these variants might modulate the A1AR distribution and availability in different brain regions. In this pilot study, the influence of ADORA1 and ADORA2A variants on in vivo A1AR binding was assessed with the A1AR-selective positron emission tomography (PET) radioligand [(18)F]CPFPX in brains of healthy humans. Twenty-eight normal control subjects underwent PET procedures to calculate the binding potential BPND of [(18)F]CPFPX in cerebral regions and to assess ADORA1 and ADORA2A single nucleotide polymorphism (SNP) effects on regional BPND data. Our results revealed SNPs of both genes associated with [(18)F]CPFPX binding to the A1AR. The strongest effects that withstood even Bonferroni correction of multiple SNP testing were found in non-smoking subjects (N=22) for ADORA2A SNPs rs2236624 and rs5751876 (corr. Pall<0.05). SNP alleles previously identified at risk for increased anxiety like the rs5751876 T-allele corresponded to consistently higher A1AR availability in all brain regions. Our data indicate for the first time that variation of A1AR availability was associated with ADORA SNPs. The finding of increased A1AR availability in regions of the fear network, particularly in ADORA2A risk allele carriers, strongly warrants evaluation and replication in further studies including individuals with increased anxiety.
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Affiliation(s)
- Christa Hohoff
- Department of Psychiatry and Psychotherapy, University of Münster, Münster, Germany,Department of Psychiatry and Psychotherapy,, University of Münster, Albert-Schweitzer-Campus 1, A9, 48149 Münster, Germany, Phone: +4925 1835 7122; Fax: +4925 1835 7123, E-mail:
| | - Valentina Garibotto
- Institute of Neuroscience and Medicine (INM-2), Forschungszentrum Jülich, Jülich, Germany
| | - David Elmenhorst
- Institute of Neuroscience and Medicine (INM-2), Forschungszentrum Jülich, Jülich, Germany
| | - Anna Baffa
- Department of Psychiatry and Psychotherapy, University of Münster, Münster, Germany
| | - Tina Kroll
- Institute of Neuroscience and Medicine (INM-2), Forschungszentrum Jülich, Jülich, Germany
| | - Alana Hoffmann
- Department of Psychiatry and Psychotherapy, University of Münster, Münster, Germany
| | - Kathrin Schwarte
- Department of Psychiatry and Psychotherapy, University of Münster, Münster, Germany
| | - Weiqi Zhang
- Department of Psychiatry and Psychotherapy, University of Münster, Münster, Germany
| | - Volker Arolt
- Department of Psychiatry and Psychotherapy, University of Münster, Münster, Germany
| | - Jürgen Deckert
- Department of Psychiatry, Psychosomatics and Psychotherapy, University of Würzburg, Würzburg, Germany
| | - Andreas Bauer
- Institute of Neuroscience and Medicine (INM-2), Forschungszentrum Jülich, Jülich, Germany
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Ardais A, Borges M, Rocha A, Sallaberry C, Cunha R, Porciúncula L. Caffeine triggers behavioral and neurochemical alterations in adolescent rats. Neuroscience 2014; 270:27-39. [DOI: 10.1016/j.neuroscience.2014.04.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2014] [Revised: 03/31/2014] [Accepted: 04/01/2014] [Indexed: 12/01/2022]
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Pitchon DN, Zook M, Rhoads DE. A Pattern of Adolescent Caffeine Consumption that Reduces Alcohol Withdrawal Severity. JOURNAL OF CAFFEINE RESEARCH 2013. [DOI: 10.1089/jcr.2013.0011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Darsi N. Pitchon
- Department of Biology, Monmouth University, W. Long Branch, New Jersey
| | - Michelle Zook
- Department of Biology, Monmouth University, W. Long Branch, New Jersey
| | - Dennis E. Rhoads
- Department of Biology, Monmouth University, W. Long Branch, New Jersey
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Lu M, Farnebo LO, Bränström R, Larsson C. Inhibition of parathyroid hormone secretion by caffeine in human parathyroid cells. J Clin Endocrinol Metab 2013; 98:E1345-51. [PMID: 23788688 PMCID: PMC4207951 DOI: 10.1210/jc.2013-1466] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
CONTEXT AND OBJECTIVE Caffeine is a highly consumed psychoactive substance present in our daily drinks. Independent studies have reported associations between caffeine consumption, low bone mineral density, and urinary calcium loss, as well as impaired bone development in vitro and in vivo. Calcium (Ca(2+)), vitamin D, and PTH are critical regulators of bone remodeling. A possible association between caffeine and parathyroid gland function has been suggested in the literature. DESIGN, SETTING, AND PATIENTS Effects of caffeine on PTH secretion and Ca(2+) levels were determined by batch incubation and Fura-2, respectively, in pathological parathyroid cells. Protein expressions were studied by Western blot and immunohistochemistry in normal and parathyroid adenoma tissues. Alterations in gene expressions of adenosine receptor A1 (ADORA1) and A2 (ADORA2A) and PTH were quantified by PCR; intracellular cAMP levels and protein kinase A activity were analyzed by an antibody-based assay. RESULTS We studied physiological concentrations of caffeine ranging from 1 to 50 μm and found that 50 μm caffeine caused a significant decrease of PTH secretion and PTH gene expression. This decrease occurred in parallel with a decrease of the intracellular cAMP level, protein kinase A activity, and ADORA1 gene expression, indicating a possible causal relationship. The intracellular level of Ca(2+) was unaffected even by high concentrations of caffeine. Protein expressions demonstrated two main targets for caffeine-ADORA1 and ADORA2A. CONCLUSION A physiological high dose of caffeine inhibits PTH secretion in human parathyroid cells, possibly due to a decrease of the intracellular level of cAMP. The observation demonstrates a functional link between caffeine and parathyroid cell function.
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Affiliation(s)
- Ming Lu
- Department of Molecular Medicine and Surgery, Karolinska Institutet, SE-171 76 Stockholm, Sweden.
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Profile of nucleotide catabolism and ectonucleotidase expression from the hippocampi of neonatal rats after caffeine exposure. Neurochem Res 2011; 37:23-30. [PMID: 21842269 DOI: 10.1007/s11064-011-0577-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Revised: 07/18/2011] [Accepted: 08/04/2011] [Indexed: 10/17/2022]
Abstract
Nucleotides and nucleosides play an important role in neurodevelopment acting through specific receptors. Ectonucleotidases are the major enzymes involved in controlling the availability of purinergic receptors ligands. ATP is co-released with several neurotransmitters and is the most important source of extracellular adenosine by catabolism exerted by ectonucleotidases. The main ectonucleotidases are named NTPDases (1-8) and 5'-nucleotidase. Adenosine is a powerful modulator of neurotransmitter release. Caffeine blocks adenosine receptor activity as well as adenosine-mediated neuromodulation. Considering the susceptibility of the immature brain to caffeine and the need for correct purinergic signaling during fetal development, we have analyzed the effects of caffeine exposure during gestational and lactational periods on nucleotide degradation and ectonucleotidase expression from the hippocampi of 7-, 14- and 21-days-old rats. Nucleotides hydrolysis was assessed by colorimetric determination of inorganic phosphate released. Ectonucleotidases expression was performed by RT-PCR. ATP and ADP hydrolysis displayed parallel age-dependent decreases in both control and caffeine-treated groups. AMP hydrolysis increased with caffeine treatment in 7-days-old rats (75%); although there was no significant difference in AMP hydrolysis between control (non caffeine-treated) rats and 14- or 21-days caffeine-treated rats. ADP hydrolysis was not affected by caffeine treatment. Caffeine treatment in 7- and 14-days-old rats decreased ATP hydrolysis when compared to the control group (19% and 60% decrease, respectively), but 21-days-treated rats showed an increase in ATP hydrolysis (39%). Expression levels of NTPDase 1 and 5 decreased in hippocampi of caffeine-treated rats. The expression of 5'-nucleotidase was not affected after caffeine exposure. The changes observed in nucleotide hydrolysis and ectonucleotidases expression could promote subtle effects on normal neural development considering the neuromodulatory role of adenosine.
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Rhoads DE, Huggler AL, Rhoads LJ. Acute and adaptive motor responses to caffeine in adolescent and adult rats. Pharmacol Biochem Behav 2011; 99:81-6. [PMID: 21504758 DOI: 10.1016/j.pbb.2011.04.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2011] [Revised: 03/26/2011] [Accepted: 04/04/2011] [Indexed: 11/18/2022]
Abstract
Caffeine is a psychostimulant with intake through foods or beverages tending to increase from childhood through adolescence. The goals of the present study were to examine the effects of caffeine on young adolescent Long-Evans rats and to compare the motor-behavioral responses of adolescent and adult rats to acute and chronic caffeine. Adolescent rats had a biphasic dose-response to caffeine comparable to that reported for adult rats. The magnitude of the motor response to a challenge dose of caffeine (30mg/kg, ip) was similar between adolescent and adult rats. Administration of caffeine in the drinking water (1mg/ml) for a period of 2 weeks led to overall consumption of caffeine which was not significantly different between adolescents and adults when normalized to body mass. There were no impacts of caffeinated drinking water on volume of fluid consumed nor weight gain in either age group compared to age matched controls drinking non-caffeinated tap water. Following this period of caffeine consumption, return to regular drinking water (caffeine withdrawal) led to a significant decrease in baseline movement compared to caffeine-naïve rats. This effect inversion was observed for adolescents but not adults. In addition, the response of the adolescents to the challenge dose of caffeine (30mg/kg, ip) was reduced significantly after chronic caffeine consumption and withdrawal. This apparent tolerance to the caffeine challenge dose was not seen with the adults. Thus, the developing brain of these adolescents may show similar sensitivity to adults in acute caffeine exposure but greater responsiveness to adaptive changes associated with chronic caffeine consumption.
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Affiliation(s)
- Dennis E Rhoads
- Department of Biology, Monmouth University, W. Long Branch, NJ 07764, USA.
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Abstract
Clinical evidence, in particular the wide use of theophylline as a bronchodilator, suggests that methylxanthines can cause seizures in patients without known underlying epilepsy. Theophylline is also known to be an added risk factor for seizure exacerbation in patients with epilepsy. The proconvulsant activity of methylxanthines can best be explained by their antagonizing the brain's own anticonvulsant adenosine. Recent evidence suggests that adenosine dysfunction is a pathological hallmark of epilepsy contributing to seizure generation and seizure spread. Conversely, adenosine augmentation therapies are effective in seizure suppression and prevention, whereas adenosine receptor antagonists such as methylxanthines generally exacerbate seizures. The impact of the methylxanthines caffeine and theophylline on seizures and excitotoxicity depends on timing, dose, and acute versus chronic use. New findings suggest a role of free radicals in theophylline-induced seizures, and adenosine-independent mechanisms for seizure generation have been proposed.
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Affiliation(s)
- Detlev Boison
- R.S. Dow Neurobiology Laboratories, Legacy Research, Portland, OR 97232, USA
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Brothers HM, Marchalant Y, Wenk GL. Caffeine attenuates lipopolysaccharide-induced neuroinflammation. Neurosci Lett 2010; 480:97-100. [PMID: 20541589 DOI: 10.1016/j.neulet.2010.06.013] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2010] [Revised: 06/01/2010] [Accepted: 06/03/2010] [Indexed: 12/19/2022]
Abstract
Caffeine is an antagonist at A1 and A2A adenosine receptors and epidemiological evidence suggests that caffeine consumption reduces the risk of Alzheimer's and Parkinson's diseases. Neuroinflammation plays a role in the etiology of these diseases and caffeine may provide protection through the modulation of inflammation. Adenosine has a known role in the propagation of inflammation and caffeine may reduce microglia activation directly by blocking adenosine receptors on microglia. Chronic neuroinflammation is associated with an increase in extracellular levels of glutamate and drugs that limit the effects of glutamate at neuronal receptors have been shown to indirectly reduce the neuroinflammatory response of microglia cells. A1 and A2A receptors have been shown to regulate the pre-synaptic release of glutamate, therefore, caffeine may also reduce neuroinflammation via its ability to regulate glutamate release. Caffeine was administered at various doses to young rats with experimentally induced neuroinflammation by chronic infusion of lipopolysaccharide (LPS) over two or four weeks into the 4th ventricle and to aged rats with naturally elevated levels of microglia activation. Caffeine attenuated the number of activated microglia within the hippocampus of animals with LPS-induced and age-related inflammation.
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Affiliation(s)
- Holly M Brothers
- Department of Psychology, Ohio State University, Columbus, OH 43210, United States
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Lorenzo A, León D, Castillo C, Ruiz M, Albasanz J, Martín M. Maternal caffeine intake during gestation and lactation down-regulates adenosine A1receptor in rat brain from mothers and neonates. J Neurosci Res 2009; 88:1252-61. [DOI: 10.1002/jnr.22287] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Han ME, Kim HJ, Lee YS, Kim DH, Choi JT, Pan CS, Yoon S, Baek SY, Kim BS, Kim JB, Oh SO. Regulation of cerebrospinal fluid production by caffeine consumption. BMC Neurosci 2009; 10:110. [PMID: 19725982 PMCID: PMC2744679 DOI: 10.1186/1471-2202-10-110] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2009] [Accepted: 09/03/2009] [Indexed: 11/17/2022] Open
Abstract
Background Caffeine is the most commonly consumed psycho-stimulant in the world. The effects of caffeine on the body have been extensively studied; however, its effect on the structure of the brain has not been investigated to date. Results In the present study we found that the long-term consumption of caffeine can induce ventriculomegaly; this was observed in 40% of the study rats. In the caffeine-treated rats with ventriculomegaly, there was increased production of CSF, associated with the increased expression of Na+, K+-ATPase and increased cerebral blood flow (CBF). In contrast to the chronic effects, acute treatment with caffeine decreased the production of CSF, suggesting 'effect inversion' associated with caffeine, which was mediated by increased expression of the A1 adenosine receptor, in the choroid plexus of rats chronically treated with caffeine. The involvement of the A1 adenosine receptor in the effect inversion of caffeine was further supported by the induction of ventriculomegaly and Na+, K+-ATPase, in A1 agonist-treated rats. Conclusion The results of this study show that long-term consumption of caffeine can induce ventriculomegaly, which is mediated in part by increased production of CSF. Moreover, we also showed that adenosine receptor signaling can regulate the production of CSF by controlling the expression of Na+, K+-ATPase and CBF.
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Affiliation(s)
- Myoung-Eun Han
- Department of Anatomy, School of Medicine, Pusan National University, Busan, South Korea.
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Nantwi KD. Recovery of respiratory activity after C2 hemisection (C2HS): involvement of adenosinergic mechanisms. Respir Physiol Neurobiol 2009; 169:102-14. [PMID: 19651244 DOI: 10.1016/j.resp.2009.07.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Revised: 07/14/2009] [Accepted: 07/14/2009] [Indexed: 11/18/2022]
Abstract
Consequences of spinal cord injury (SCI) depend on the level and extent of injury. Cervical SCI often results in a compromised respiratory system. Primary treatment of SCI patients with respiratory insufficiency continues to be with mechanical ventilatory support. In an animal model of SCI, an upper cervical spinal cord hemisection paralyzes the hemidiaphragm ipsilateral to the side of injury. However, a latent respiratory motor pathway can be activated to restore respiratory function after injury. In this review, restoration of respiratory activity following systemic administration of theophylline, a respiratory stimulant will be discussed. Pharmacologically, theophylline is a non-specific adenosine receptor antagonist, a phosphodiesterase inhibitor and a bronchodilator. It has been used in the treatment of asthma and other respiratory-related diseases such as chronic obstructive pulmonary disease (COPD) and in treatment of apnea in premature infants. However, the clinical use of theophylline to improve respiration in SCI patients with respiratory deficits is a more recent approach. This review will focus on the use of theophylline to restore respiratory activity in an animal model of SCI. In this model, a C2 hemisection (C2HS) interrupts the major descending respiratory pathways and paralyzes the ipsilateral hemidiaphragm. The review also highlights involvement of central and peripheral adenosine receptors in functional restitution. Biochemical binding assays that highlight changes in adenosine receptors after chronic theophylline administration are discussed as they pertain to understanding adenosine receptor-mediation in functional recovery. Finally, the clinical application of theophylline in SCI patients with respiratory deficits in particular is discussed.
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Affiliation(s)
- Kwaku D Nantwi
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, MI 48202, USA.
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Sihver W, Schulze A, Wutz W, Stüsgen S, Olsson RA, Bier D, Holschbach MH. Autoradiographic comparison of in vitro binding characteristics of various tritiated adenosine A2A receptor ligands in rat, mouse and pig brain and first ex vivo results. Eur J Pharmacol 2009; 616:107-14. [PMID: 19545560 DOI: 10.1016/j.ejphar.2009.06.025] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2009] [Revised: 05/29/2009] [Accepted: 06/09/2009] [Indexed: 02/08/2023]
Abstract
The adenosine A(2A) receptor in the basal ganglia is involved in the control of movement and plays a role in movement disorders such as Parkinsonism. Developing ligands to evaluate that receptor by noninvasive methods such as positron emission tomography has a high priority. In vitro radioligand binding guides the selection of ligands for in vivo application. This study measured the binding of the adenosine A(2A) receptor antagonist [(3)H]MSX-2 (3-(3-hydroxypropyl)-8-m-methoxystyryl)-7-methyl-1-propargylxanthine) to rat, mouse and pig brain by autoradiography. Other studies measured binding to membranes from PC12 pheochromocytoma cells. Those binding parameters were compared to those of the adenosine A(2A) receptor antagonist [(3)H]ZM241385 (4-(2-[7-amino-2-(2-furyl)[1,2,4]triazolo[2,3-a][1,3,5]triazin-5-ylamino)ethyl)phenol), the adenosine A(2A) receptor agonist [(3)H]CGS21680 (2-[p-(2-carboxyethyl)-phenethylamino]-5'-N-ethylcarboxamidoadenosine) and the unselective adenosine receptor agonist [(3)H]NECA (5'N-ethylcarboxamido)adenosine). The potency order (K(d)) in the three species was [(3)H]ZM241385<[(3)H]MSX-2<[(3)H]NECA<[(3)H]CGS21680. The density of [(3)H]MSX-2 binding sites was greater in the striatum than in the cortex. Preliminary ex vivo experiments showed that by 10min after iv injection, [(3)H]MSX-2 and [(3)H]CGS21680 crossed the blood-brain barrier to the extent of almost 1% ID/g brain tissue, but [(3)H]NECA and [(3)H]ZM241385 to only 0.2% ID/g. The prior administration of unlabeled ZM241385 significantly lowered brain uptake of [(3)H]MSX-2. In conclusion, [(3)H]MSX-2 has a high affinity and sufficient selectivity for the adenosine A(2A) receptor. It penetrates the blood-brain barrier. Sensitivity to photoisomerization is a limitation. Further investigations assess its suitability as a ligand for imaging the brain adenosine A(2A) receptor.
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Affiliation(s)
- Wiebke Sihver
- Institute of Neuroscience and Medicine, INM-5, (Nuclear Chemistry), Research Center Jülich, 52425 Jülich, Germany.
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Sachse KT, Jackson EK, Wisniewski SR, Gillespie DG, Puccio AM, Clark RSB, Dixon CE, Kochanek PM. Increases in cerebrospinal fluid caffeine concentration are associated with favorable outcome after severe traumatic brain injury in humans. J Cereb Blood Flow Metab 2008; 28:395-401. [PMID: 17684518 PMCID: PMC3714395 DOI: 10.1038/sj.jcbfm.9600539] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Caffeine, the most widely consumed psychoactive drug and a weak adenosine receptor antagonist, can be neuroprotective or neurotoxic depending on the experimental model or neurologic disorder. However, its contribution to pathophysiology and outcome in traumatic brain injury (TBI) in humans is undefined. We assessed serial cerebrospinal fluid (CSF) concentrations of caffeine and its metabolites (theobromine, paraxanthine, and theophylline) by high-pressure liquid chromatography/ultraviolet in 97 ventricular CSF samples from an established bank, from 30 adults with severe TBI. We prospectively selected a threshold caffeine level of > or = 1 micromol/L (194 ng/mL) as clinically significant. Demographics, Glasgow Coma Scale (GCS) score, admission blood alcohol level, and 6-month dichotomized Glasgow Outcome Scale (GOS) score were assessed. Mean time from injury to initial CSF sampling was 10.77+/-3.13 h. On initial sampling, caffeine was detected in 24 of 30 patients, and the threshold was achieved in 9 patients. Favorable GOS was seen more often in patients with CSF caffeine concentration > or = versus < the threshold (55.6 versus 11.8%, P=0.028). Gender, age, admission CGS score, admission blood alcohol level, and admission systolic arterial blood pressure did not differ between patients with CSF caffeine concentration > or = versus < the threshold. Increases in CSF concentrations of the caffeine metabolites theobromine and paraxanthine were also associated with favorable outcome (P=0.018 and 0.056, respectively). Caffeine and its metabolites are commonly detected in CSF in patients with severe TBI and in an exploratory assessment are associated with favorable outcome. We speculate that caffeine may be neuroprotective by long-term upregulation of adenosine A1 receptors or acute inhibition of A2a receptors.
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Affiliation(s)
- Kathleen T Sachse
- Department of Critical Care Medicine, Safar Center for Resuscitation Research, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15260, USA
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Maternal caffeine intake affects acetylcholinesterase in hippocampus of neonate rats. Int J Dev Neurosci 2008; 26:339-43. [DOI: 10.1016/j.ijdevneu.2007.12.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2007] [Revised: 12/20/2007] [Accepted: 12/26/2007] [Indexed: 11/19/2022] Open
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Bendlin BB, Trouard TP, Ryan L. Caffeine attenuates practice effects in word stem completion as measured by fMRI BOLD signal. Hum Brain Mapp 2007; 28:654-62. [PMID: 17094121 PMCID: PMC6871275 DOI: 10.1002/hbm.20295] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Caffeine ingestion results in increased brain cell metabolism (Nehlig et al. [1992] Brain Res Brain Res Rev 17:139-170) and decreased cerebral blood flow (Field et al. [2003] Radiology 227:129-135; Mulderink et al. [2002] Neuroimage 15:37-44). The current study investigated the effect of caffeine in a word stem completion task using only novel word stems (no repeated stimuli). Resting perfusion was measured with arterial spin labeled perfusion MRI, along with blood oxygenation level-dependent (BOLD) signal before and after ingestion of regular coffee, decaffeinated coffee, and water. Based on previous research (Laurienti et al. [2002] Neuroimage 17:751-757; Mulderink et al. [2002] Neuroimage 15:37-44), we hypothesized that caffeine would result in increased BOLD signal intensity and extent of BOLD activation. As expected, caffeine resulted in a significant decrease in cerebral perfusion. However, both the control and caffeine groups showed an increase in BOLD signal amplitude across two sets of novel word stems. Additionally, the control group showed a 50% reduction in the extent of BOLD activation, while the caffeine group showed no change in activation extent. Neither group showed changes in BOLD baseline signal over time, which had been suggested to mediate caffeine-related BOLD signal changes. The results suggest that caffeine may attenuate general task practice effects that have been described in recent functional MRI studies of word stem completion (Buckner et al. [2000] Brain 123:620-640).
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Affiliation(s)
- Barbara B. Bendlin
- Department of Psychology, Cognition and Neuroimaging Laboratories, University of Arizona, Tucson, Arizona
| | - Theodore P. Trouard
- Biomedical Engineering Program, Cognition and Neuroimaging Laboratories, University of Arizona, Tucson, Arizona
| | - Lee Ryan
- Department of Psychology, Cognition and Neuroimaging Laboratories, University of Arizona, Tucson, Arizona
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Elmenhorst D, Meyer PT, Matusch A, Winz OH, Zilles K, Bauer A. Test–retest stability of cerebral A1 adenosine receptor quantification using [18F]CPFPX and PET. Eur J Nucl Med Mol Imaging 2007; 34:1061-70. [PMID: 17242921 DOI: 10.1007/s00259-006-0309-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2006] [Accepted: 10/14/2006] [Indexed: 10/23/2022]
Abstract
PURPOSE The goal of the present study was to evaluate the reproducibility of cerebral A1 adenosine receptor (A1AR) quantification using [18F]CPFPX and PET in a test-retest design. METHODS Eleven healthy volunteers were studied twice. Eight brain regions ranging from high to low receptor binding were examined. [18F]CPFPX was injected as a bolus with subsequent infusion over 120 min. Various outcome parameters were compared based on either metabolite-corrected venous blood sampling [e.g. apparent equilibrium total distribution volume (DVt')] or a reference region [ratio of specific to non-specific distribution volume (BP2)]. RESULTS Test-retest variability was low in the outcome measure BP2 (on average 5.9%) and moderate in DVt' (on average 13.2%). Regarding reproducibility, the outcome parameter BP2 showed an intra-class correlation coefficient (ICC) of 0.94 +/- 0.1. For DVt' the between-subject coefficient of variation (%CV) was similar to the within-subject %CV (around 10%), resulting in a poor ICC of 0.06 +/- 0.2. CONCLUSION Our results suggest that quantification of [18F]CPFPX imaging is reproducible and reliable for PET studies of the cerebral A1AR. Among the outcome parameters the non-invasive measures were of superior test-retest stability over the invasive.
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Affiliation(s)
- David Elmenhorst
- Institute of Medicine, Research Centre Jülich, 52425 Jülich, Germany
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Petrov T, Kreipke C, Alilain W, Nantwi KD. Differential expression of adenosine A1 and A2A receptors after upper cervical (C2) spinal cord hemisection in adult rats. J Spinal Cord Med 2007; 30:331-7. [PMID: 17853654 PMCID: PMC2031933 DOI: 10.1080/10790268.2007.11753948] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
Abstract
BACKGROUND In an animal model of spinal cord injury, a latent respiratory motor pathway can be pharmacologically activated via adenosine receptors to restore respiratory function after cervical (C2) spinal cord hemisection that paralyzes the hemidiaphragm ipsilateral to injury. Although spinal phrenic motoneurons immunopositive for adenosine receptors have been demonstrated (C3-C5), it is unclear if adenosine receptor protein levels are altered after C2 hemisection and theophylline administration. OBJECTIVE To assess the effects of C2 spinal cord hemisection and theophylline administration on the expression of adenosine receptor proteins. METHODS Adenosine A1 and A2A receptor protein levels were assessed in adult rats classified as (a) noninjured and theophylline treated, (b) C2 hemisected, (c) C2 hemisected and administered theophylline orally (3x daily) for 3 days only, and (d) C2 hemisected and administered theophylline (3x daily for 3 days) and assessed 12 days after drug administration. Assessment of A1 protein levels was carried out via immunohistochemistry and A2A protein levels by densitometry. RESULTS Adenosine A1 protein levels decreased significantly (both ipsilateral and contralateral to injury) after C2 hemisection; however, the decrease was attenuated in hemisected and theophylline-treated animals. Attenuation in adenosine A1 receptor protein levels persisted when theophylline administration was stopped for 12 days prior to assessment. Adenosine A2A protein levels were unchanged by C2 hemisection; however, theophylline reduced the levels within the phrenic motoneurons. Furthermore, the decrease in A2A levels persisted 12 days after theophylline was withdrawn. CONCLUSION Our findings suggest that theophylline mitigates the effects of C2 hemisection by attenuating the C2 hemisection-induced decrease in A1 protein levels. Furthermore, A2A protein levels are unaltered by C2 hemisection but decrease after continuous or interrupted theophylline administration. The effects on protein levels may underlie the stimulant actions of theophylline.
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Affiliation(s)
- Theodor Petrov
- Department of Anatomy and Cell Biology, Wayne State University, School of Medicine, Detroit, Michigan
| | - Christian Kreipke
- Department of Anatomy and Cell Biology, Wayne State University, School of Medicine, Detroit, Michigan
| | - Warren Alilain
- Department of Anatomy and Cell Biology, Wayne State University, School of Medicine, Detroit, Michigan
| | - Kwaku D Nantwi
- Department of Anatomy and Cell Biology, Wayne State University, School of Medicine, Detroit, Michigan
- Please address correspondence to Kwaku D. Nantwi, PhD, Wayne State University, Department of Anatomy and Cell Biology, 8326 Scott Hall, 540 East Canfield, Detroit, MI 48202; phone: 313.577.7925; fax: 313.577.3125 (e-mail: )
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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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Wu WP, Hao JX, Fredholm BB, Wiesenfeld-Hallin Z, Xu XJ. Effect of acute and chronic administration of caffeine on pain-like behaviors in rats with partial sciatic nerve injury. Neurosci Lett 2006; 402:164-6. [PMID: 16644114 DOI: 10.1016/j.neulet.2006.03.065] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2005] [Revised: 03/28/2006] [Accepted: 03/29/2006] [Indexed: 10/24/2022]
Abstract
Caffeine, used in many pain medications as an adjuvant analgesic, is an adenosine A1 and A2A receptor antagonist. Here we examined the effects of acute or chronic caffeine administration in rats after partial sciatic nerve injury. The hindpaw response to mechanical or cold stimulation was assessed following photochemically induced sciatic nerve injury which leads to hypersensitivity to these stimuli. Caffeine was administered i.p. acutely or in the drinking water chronically. The mechanical and cold hypersensitivity of sciatic nerve-injured rats was dose-dependently alleviated by acute systemic administration of caffeine (10-80 mg/kg). The effect of caffeine was, however, associated with side effects including locomotor stimulation or depression. Chronic oral administration (average daily doses 27.5 mg/kg/day or 61.5 mg/kg/day for 2 weeks) of caffeine starting at the time of nerve injury did not significantly affect the development of pain-like behaviors. Thus, acute, but not long term, caffeine intake reduced neuropathic pain state in nerve-injured rats, but only at very high doses. The potential hyperalgesic effect of chronic A1 adenosine receptor blockade may have been compensated for by an antinociceptive effect of caffeine through antagonism of A2A receptors and tolerance development.
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Affiliation(s)
- Wei-Ping Wu
- Section of Clinical Neurophysiology, Karolinska University Hospital-Huddinge, Karolinska Institutet, S-141 86 Stockholm, Sweden.
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Iglesias I, León D, Ruiz MA, Albasanz JL, Martín M. Chronic intake of caffeine during gestation down regulates metabotropic glutamate receptors in maternal and fetal rat heart. Amino Acids 2006; 30:257-66. [PMID: 16601928 DOI: 10.1007/s00726-005-0293-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2005] [Accepted: 12/12/2005] [Indexed: 10/24/2022]
Abstract
Caffeine is the most widely consumed substance in the world which antagonizes adenosine effects. Adenosine acting through A(1) receptors inhibits glutamate release which binds to metabotropic glutamate receptors (mGluRs). Recently, we have shown that maternal caffeine intake during gestation causes down-regulation of A(1) and metabotropic glutamate receptors in the brain of both rat mothers and fetuses. In the present work we provide evidence that caffeine also affects receptors in hearts, causing a decrease in mGluRs from both maternal and fetal hearts. A decrease in G(q/11) and PLC beta(1) proteins level was also observed in both tissues. However, phospholipase C activity was only affected in fetal heart, being significantly decreased. These results suggest an in vivo cross-talk mechanism between adenosine and glutamate receptors in peripheral tissues. Therefore, special attention should be paid to caffeine ingestion during gestation.
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Affiliation(s)
- I Iglesias
- Department of Inorganic, Organic and Biochemistry, Faculty of Chemical Sciences, Centro Regional de Investigaciones Biomédicas, Ciudad Real, Spain
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Brown GG, Eyler LT. Methodological and Conceptual Issues in Functional Magnetic Resonance Imaging: Applications to Schizophrenia Research. Annu Rev Clin Psychol 2006; 2:51-81. [PMID: 17716064 DOI: 10.1146/annurev.clinpsy.2.022305.095241] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Functional magnetic resonance imaging (MRI) is a noninvasive, highly repeatable, and increasingly available method to study disordered brain activity among patients with psychological or neurological disorders. In this chapter the biophysical principles underlying functional MRI are presented, and methodological limitations of the method are discussed. Artifacts related to the biophysical basis of the functional MRI signal or associated with image acquisition methods are presented, as are artifacts related to baseline effects-especially those associated with medication, caffeine, and nicotine use. The difficulties associated with the comparison of groups of subjects differing in performance receive special attention. The limitations of cognitive subtraction designs for functional MRI are also discussed. Functional MRI studies of schizophrenia patients are used to illustrate these points.
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Affiliation(s)
- Gregory G Brown
- Psychology Service, Veterans Administration San Diego Healthcare System, and Psychiatry Department, University of California, San Diego, California 92161, USA.
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