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Lin YS, Lange D, Baur DM, Foerges A, Chu C, Li C, Elmenhorst EM, Neumaier B, Bauer A, Aeschbach D, Landolt HP, Elmenhorst D. Repeated caffeine intake suppresses cerebral grey matter responses to chronic sleep restriction in an A 1 adenosine receptor-dependent manner: a double-blind randomized controlled study with PET-MRI. Sci Rep 2024; 14:12724. [PMID: 38830861 PMCID: PMC11148136 DOI: 10.1038/s41598-024-61421-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 05/03/2024] [Indexed: 06/05/2024] Open
Abstract
Evidence has shown that both sleep loss and daily caffeine intake can induce changes in grey matter (GM). Caffeine is frequently used to combat sleepiness and impaired performance caused by insufficient sleep. It is unclear (1) whether daily use of caffeine could prevent or exacerbate the GM alterations induced by 5-day sleep restriction (i.e. chronic sleep restriction, CSR), and (2) whether the potential impact on GM plasticity depends on individual differences in the availability of adenosine receptors, which are involved in mediating effects of caffeine on sleep and waking function. Thirty-six healthy adults participated in this double-blind, randomized, controlled study (age = 28.9 ± 5.2 y/; F:M = 15:21; habitual level of caffeine intake < 450 mg; 29 homozygous C/C allele carriers of rs5751876 of ADORA2A, an A2A adenosine receptor gene variant). Each participant underwent a 9-day laboratory visit consisting of one adaptation day, 2 baseline days (BL), 5-day sleep restriction (5 h time-in-bed), and a recovery day (REC) after an 8-h sleep opportunity. Nineteen participants received 300 mg caffeine in coffee through the 5 days of CSR (CAFF group), while 17 matched participants received decaffeinated coffee (DECAF group). We examined GM changes on the 2nd BL Day, 5th CSR Day, and REC Day using magnetic resonance imaging and voxel-based morphometry. Moreover, we used positron emission tomography with [18F]-CPFPX to quantify the baseline availability of A1 adenosine receptors (A1R) and its relation to the GM plasticity. The results from the voxel-wise multimodal whole-brain analysis on the Jacobian-modulated T1-weighted images controlled for variances of cerebral blood flow indicated a significant interaction effect between caffeine and CSR in four brain regions: (a) right temporal-occipital region, (b) right dorsomedial prefrontal cortex (DmPFC), (c) left dorsolateral prefrontal cortex (DLPFC), and (d) right thalamus. The post-hoc analyses on the signal intensity of these GM clusters indicated that, compared to BL, GM on the CSR day was increased in the DECAF group in all clusters but decreased in the thalamus, DmPFC, and DLPFC in the CAFF group. Furthermore, lower baseline subcortical A1R availability predicted a larger GM reduction in the CAFF group after CSR of all brain regions except for the thalamus. In conclusion, our data suggest an adaptive GM upregulation after 5-day CSR, while concomitant use of caffeine instead leads to a GM reduction. The lack of consistent association with individual A1R availability may suggest that CSR and caffeine affect thalamic GM plasticity predominantly by a different mechanism. Future studies on the role of adenosine A2A receptors in CSR-induced GM plasticity are warranted.
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Affiliation(s)
- Yu-Shiuan Lin
- Centre for Chronobiology, University Psychiatric Clinics Basel, Wilhelm Kleinstr. 27, 4002, Basel, Switzerland.
- Research Cluster Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland.
- Athinoula. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachussetts General Hospital, Harvard Medical School, Boston, USA.
| | - Denise Lange
- Department of Sleep and Human Factors, Institute of Aerospace Medicine, German Aerospace Center, Cologne, Germany
| | - Diego Manuel Baur
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
- Sleep & Health Zurich, University Center of Competence, University of Zurich, Zurich, Switzerland
| | - Anna Foerges
- Institute of Neuroscience and Medicine, INM-2, Forschungszentrum Jülich, Wilhelm-Johnen-Strasse, 52428, Jülich, North Rhine-Westphalia, Germany
- Department of Neurophysiology, Institute of Zoology (Bio-II), RWTH Aachen University, Aachen, Germany
| | - Congying Chu
- Institute of Neuroscience and Medicine, INM-2, Forschungszentrum Jülich, Wilhelm-Johnen-Strasse, 52428, Jülich, North Rhine-Westphalia, Germany
| | - Changhong Li
- Institute of Neuroscience and Medicine, INM-2, Forschungszentrum Jülich, Wilhelm-Johnen-Strasse, 52428, Jülich, North Rhine-Westphalia, Germany
| | - Eva-Maria Elmenhorst
- Department of Sleep and Human Factors, Institute of Aerospace Medicine, German Aerospace Center, Cologne, Germany
- Institute for Occupational, Social, and Environmental Medicine, RWTH Aachen University, Aachen, Germany
| | - Bernd Neumaier
- Institute of Neuroscience and Medicine, INM-5, Forschungszentrum Jülich, Jülich, Germany
| | - Andreas Bauer
- Institute of Neuroscience and Medicine, INM-2, Forschungszentrum Jülich, Wilhelm-Johnen-Strasse, 52428, Jülich, North Rhine-Westphalia, Germany
| | - Daniel Aeschbach
- Department of Sleep and Human Factors, Institute of Aerospace Medicine, German Aerospace Center, Cologne, Germany
- Institute of Experimental Epileptology and Cognition Research, University of Bonn Medical Center, Bonn, Germany
| | - Hans-Peter Landolt
- Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
- Sleep & Health Zurich, University Center of Competence, University of Zurich, Zurich, Switzerland
| | - David Elmenhorst
- Institute of Neuroscience and Medicine, INM-2, Forschungszentrum Jülich, Wilhelm-Johnen-Strasse, 52428, Jülich, North Rhine-Westphalia, Germany.
- Multimodal Neuroimaging Group, Department of Nuclear Medicine, University Hospital Cologne, Cologne, Germany.
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Song X, Kirtipal N, Lee S, Malý P, Bharadwaj S. Current therapeutic targets and multifaceted physiological impacts of caffeine. Phytother Res 2023; 37:5558-5598. [PMID: 37679309 DOI: 10.1002/ptr.8000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 08/04/2023] [Accepted: 08/17/2023] [Indexed: 09/09/2023]
Abstract
Caffeine, which shares consubstantial structural similarity with purine adenosine, has been demonstrated as a nonselective adenosine receptor antagonist for eliciting most of the biological functions at physiologically relevant dosages. Accumulating evidence supports caffeine's beneficial effects against different disorders, such as total cardiovascular diseases and type 2 diabetes. Conversely, paradoxical effects are also linked to caffeine ingestion in humans including hypertension-hypotension and tachycardia-bradycardia. These observations suggest the association of caffeine action with its ingested concentration and/or concurrent interaction with preferential molecular targets to direct explicit events in the human body. Thus, a coherent analysis of the functional targets of caffeine, relevant to normal physiology, and disease pathophysiology, is required to understand the pharmacology of caffeine. This review provides a broad overview of the experimentally validated targets of caffeine, particularly those of therapeutic interest, and the impacts of caffeine on organ-specific physiology and pathophysiology. Overall, the available empirical and epidemiological evidence supports the dose-dependent functional activities of caffeine and advocates for further studies to get insights into the caffeine-induced changes under specific conditions, such as asthma, DNA repair, and cancer, in view of its therapeutic applications.
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Affiliation(s)
- Xinjie Song
- Zhejiang Provincial Key Lab for Chemical and Biological Processing Technology of Farm Product, School of Biological and Chemical Engineering, Zhejiang University of Science and Technology, Hangzhou, China
| | - Nikhil Kirtipal
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea
| | - Sunjae Lee
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea
| | - Petr Malý
- Laboratory of Ligand Engineering, Institute of Biotechnology of the Czech Academy of Sciences v.v.i, BIOCEV Research Center, Vestec, Czech Republic
| | - Shiv Bharadwaj
- Laboratory of Ligand Engineering, Institute of Biotechnology of the Czech Academy of Sciences v.v.i, BIOCEV Research Center, Vestec, Czech Republic
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3
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Song H, Fisher J, Özen AC, Akin B, Schumann S, Bock M. Quantification of regional CMRO 2 in human brain using dynamic 17O-MRI at 3T. Z Med Phys 2023:S0939-3889(23)00086-7. [PMID: 37558527 DOI: 10.1016/j.zemedi.2023.07.004] [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: 03/31/2023] [Revised: 07/12/2023] [Accepted: 07/14/2023] [Indexed: 08/11/2023]
Abstract
OBJECTIVE To investigate the feasibility of cerebral metabolic rate of oxygen consumption (CMRO2) measurements with MRI at 3 Tesla in different brain regions. METHODS CMRO2 represents a key indicator of the physiological state of brain tissue. Dynamic 17O-MRI with inhalation of isotopically enriched 17O gas has been used to quantify global CMRO2 in brain white (WM) and gray matter (GM). However, global CMRO2 can only reflect the overall oxygen metabolism of the brain and cannot provide enough information on local tissue oxygen metabolism. To investigate the feasibility of determination of regional CMRO2 at a clinical 3 T MRI system, CMRO2 values in frontal, parietal and occipital WM and GM were determined in 5 healthy volunteers and compared to evaluate the regional differences of oxygen metabolism in WM and GM. Additionally, regional CMRO2 values were determined in deep brain structures including thalamus, dorsal striatum, caudate nucleus and insula cortex and in the cerebella, and compared with literature values from 15O-PET studies. RESULTS In cortical GM the determined CMRO2 values were in good agreement with the literature, whereas values in WM were about 32-48% higher than literature values. Regional analysis revealed a significantly higher CMRO2 in the occipital GM compared to the frontal and parietal GM. By contrast, no significant difference of CMRO2 was observed across the WM. In addition, CMRO2 in deep brain structures was lower compared to literature values and in the cerebella a good hemispheric symmetry of the tissue oxygen metabolism was found. CONCLUSION Dynamic 17O-MRI enables direct, non-invasive determination of regional CMRO2 in brain structures in healthy volunteers at 3T.
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Affiliation(s)
- Hao Song
- Division of Medical Physics, Department of Diagnostic and Interventional Radiology, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
| | - Johannes Fisher
- Division of Medical Physics, Department of Diagnostic and Interventional Radiology, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Ali Caglar Özen
- Division of Medical Physics, Department of Diagnostic and Interventional Radiology, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Burak Akin
- Section on Functional Imaging Methods, NIMH, NIH, Bethesda, MD, USA
| | - Stefan Schumann
- Department of Anesthesiology and Critical Care, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Michael Bock
- Division of Medical Physics, Department of Diagnostic and Interventional Radiology, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
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Chandler HL, Stickland RC, Patitucci E, Germuska M, Chiarelli AM, Foster C, Bhome-Dhaliwal S, Lancaster TM, Saxena N, Khot S, Tomassini V, Wise RG. Reduced brain oxygen metabolism in patients with multiple sclerosis: Evidence from dual-calibrated functional MRI. J Cereb Blood Flow Metab 2023; 43:115-128. [PMID: 36071645 PMCID: PMC9875355 DOI: 10.1177/0271678x221121849] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 06/01/2022] [Accepted: 07/21/2022] [Indexed: 01/28/2023]
Abstract
Cerebral energy deficiency is increasingly recognised as an important feature of multiple sclerosis (MS). Until now, we have lacked non-invasive imaging methods to quantify energy utilisation and mitochondrial function in the human brain. Here, we used novel dual-calibrated functional magnetic resonance imaging (dc-fMRI) to map grey-matter (GM) deoxy-haemoglobin sensitive cerebral blood volume (CBVdHb), cerebral blood flow (CBF), oxygen extraction fraction (OEF), and cerebral metabolic rate of oxygen consumption (CMRO2) in patients with MS (PwMS) and age/sex matched controls. By integrating a flow-diffusion model of oxygen transport, we evaluated the effective oxygen diffusivity of the capillary network (DC) and the partial pressure of oxygen at the mitochondria (PmO2). Significant between-group differences were observed as decreased CBF (p = 0.010), CMRO2 (p < 0.001) and DC (p = 0.002), and increased PmO2 (p = 0.043) in patients compared to controls. No significant differences were observed for CBVdHb (p = 0.389), OEF (p = 0.358), or GM volume (p = 0.302). Regional analysis showed widespread reductions in CMRO2 and DC for PwMS. Our findings may be indicative of reduced oxygen demand or utilisation in the MS brain and mitochondrial dysfunction. Our results suggest changes in brain physiology may precede MRI-detectable GM loss and may contribute to disease progression and neurodegeneration.
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Affiliation(s)
| | - Rachael C Stickland
- CUBRIC, School of Psychology, Cardiff University, Cardiff,
UK
- Department of Physical Therapy and Human Movement Sciences,
Northwestern University, Chicago, IL, USA
| | | | | | - Antonio M Chiarelli
- Institute for Advanced Biomedical Technologies, University “G.
d'Annunzio” of Chieti-Pescara, Chieti, Italy
- Department of Neurosciences, Imaging and Clinical Sciences,
University “G. d'Annunzio” of Chieti-Pescara, Chieti, Italy
| | - Catherine Foster
- CUBRIC, School of Psychology, Cardiff University, Cardiff,
UK
- Wales Institute of Social and Economic Research and Data,
Cardiff University, Cardiff, UK
| | | | - Thomas M Lancaster
- CUBRIC, School of Psychology, Cardiff University, Cardiff,
UK
- Department of Psychology, University of Bath, Bath, UK
| | - Neeraj Saxena
- CUBRIC, School of Psychology, Cardiff University, Cardiff,
UK
- Department of Anaesthetics, Intensive Care and Pain Medicine,
Cwm Taf Morgannwg University Health Board, Abercynon, UK
| | - Sharmila Khot
- CUBRIC, School of Psychology, Cardiff University, Cardiff,
UK
- Cardiff University School of Medicine, Cardiff, UK
| | - Valentina Tomassini
- CUBRIC, School of Psychology, Cardiff University, Cardiff,
UK
- Institute for Advanced Biomedical Technologies, University “G.
d'Annunzio” of Chieti-Pescara, Chieti, Italy
- Department of Neurosciences, Imaging and Clinical Sciences,
University “G. d'Annunzio” of Chieti-Pescara, Chieti, Italy
- MS Centre, Neurology Unit, “SS. Annunziata” University Hospital,
Chieti, Italy
- Division of Psychological Medicine and Clinical Neurosciences,
School of Medicine, Cardiff University, Cardiff, UK
- Helen Durham Centre for Neuroinflammation, University Hospital
of Wales, Cardiff, UK
| | - Richard G Wise
- CUBRIC, School of Psychology, Cardiff University, Cardiff,
UK
- Institute for Advanced Biomedical Technologies, University “G.
d'Annunzio” of Chieti-Pescara, Chieti, Italy
- Department of Neurosciences, Imaging and Clinical Sciences,
University “G. d'Annunzio” of Chieti-Pescara, Chieti, Italy
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5
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Wu S, Tyler LK, Henson RN, Rowe JB, Cam-CAN, Tsvetanov KA. Cerebral blood flow predicts multiple demand network activity and fluid intelligence across the adult lifespan. Neurobiol Aging 2022; 121:1-14. [PMID: 36306687 PMCID: PMC7613814 DOI: 10.1016/j.neurobiolaging.2022.09.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 09/13/2022] [Accepted: 09/14/2022] [Indexed: 10/14/2022]
Abstract
The preservation of cognitive function in old age is a public health priority. Cerebral hypoperfusion is a hallmark of dementia but its impact on maintaining cognitive ability across the lifespan is less clear. We investigated the relationship between baseline cerebral blood flow (CBF) and blood oxygenation level-dependent (BOLD) response during a fluid reasoning task in a population-based adult lifespan cohort. As age differences in CBF could lead to non-neuronal contributions to the BOLD signal, we introduced commonality analysis to neuroimaging to dissociate performance-related CBF effects from the physiological confounding effects of CBF on the BOLD response. Accounting for CBF, we confirmed that performance- and age-related differences in BOLD responses in the multiple-demand network were implicated in fluid reasoning. Age differences in CBF explained not only performance-related BOLD responses but also performance-independent BOLD responses. Our results suggest that CBF is important for maintaining cognitive function, while its non-neuronal contributions to BOLD signals reflect an age-related confound. Maintaining perfusion into old age may serve to support brain function and preserve cognitive performance.
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Affiliation(s)
- Shuyi Wu
- Centre for Speech, Language and the Brain, Department of Psychology, University of Cambridge, Cambridge, UK,Department of Management, School of Business, Hong Kong Baptist University, Hong Kong, China
| | - Lorraine K. Tyler
- Centre for Speech, Language and the Brain, Department of Psychology, University of Cambridge, Cambridge, UK
| | - Richard N.A. Henson
- Medical Research Council Cognition and Brain Sciences Unit, Department of Psychiatry, Cambridge, UK
| | - James B. Rowe
- Medical Research Council Cognition and Brain Sciences Unit, Department of Psychiatry, Cambridge, UK,Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Cam-CAN
- Centre for Speech, Language and the Brain, Department of Psychology, University of Cambridge, Cambridge, UK,Medical Research Council Cognition and Brain Sciences Unit, Department of Psychiatry, Cambridge, UK
| | - Kamen A. Tsvetanov
- Centre for Speech, Language and the Brain, Department of Psychology, University of Cambridge, Cambridge, UK,Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK,Corresponding author (, +44 1223 766 556)
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6
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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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7
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Caffeine-Induced Acute and Delayed Responses in Cerebral Metabolism of Control and Schizophrenia-Like Wisket Rats. Int J Mol Sci 2022; 23:ijms23158186. [PMID: 35897774 PMCID: PMC9331118 DOI: 10.3390/ijms23158186] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 07/21/2022] [Accepted: 07/23/2022] [Indexed: 12/04/2022] Open
Abstract
Recently, morphological impairments have been detected in the brain of a triple-hit rat schizophrenia model (Wisket), and delayed depressive effects of caffeine treatment in both control and Wisket animals have also been shown. The aims of this study were to determine the basal and caffeine-induced acute (30 min) and delayed (24 h) changes in the cerebral 18fluorodeoxyglucose (18F-FDG) uptake by positron emission tomography (PET) in control and Wisket rats. No significant differences were identified in the basal whole-brain metabolism between the two groups, and the metabolism was not modified acutely by a single intraperitoneal caffeine (20 mg/kg) injection in either group. However, one day after caffeine administration, significantly enhanced 18F-FDG uptake was detected in the whole brain and the investigated areas (hippocampus, striatum, thalamus, and hypothalamus) in the control group. Although the Wisket animals showed only moderate enhancements in the 18F-FDG uptake, significantly lower brain metabolism was observed in this group than in the caffeine-treated control group. This study highlights that the basal brain metabolism of Wisket animals was similar to control rats, and that was not influenced acutely by single caffeine treatment at the whole-brain level. Nevertheless, the distinct delayed responsiveness to this psychostimulant in Wisket model rats suggests impaired control of the cerebral metabolism.
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8
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Chiarelli AM, Germuska M, Chandler H, Stickland R, Patitucci E, Biondetti E, Mascali D, Saxena N, Khot S, Steventon J, Foster C, Rodríguez-Soto AE, Englund E, Murphy K, Tomassini V, Wehrli FW, Wise RG. A flow-diffusion model of oxygen transport for quantitative mapping of cerebral metabolic rate of oxygen (CMRO 2) with single gas calibrated fMRI. J Cereb Blood Flow Metab 2022; 42:1192-1209. [PMID: 35107026 PMCID: PMC9207485 DOI: 10.1177/0271678x221077332] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
One promising approach for mapping CMRO2 is dual-calibrated functional MRI (dc-fMRI). This method exploits the Fick Principle to combine estimates of CBF from ASL, and OEF derived from BOLD-ASL measurements during arterial O2 and CO2 modulations. Multiple gas modulations are required to decouple OEF and deoxyhemoglobin-sensitive blood volume. We propose an alternative single gas calibrated fMRI framework, integrating a model of oxygen transport, that links blood volume and CBF to OEF and creates a mapping between the maximum BOLD signal, CBF and OEF (and CMRO2). Simulations demonstrated the method's viability within physiological ranges of mitochondrial oxygen pressure, PmO2, and mean capillary transit time. A dc-fMRI experiment, performed on 20 healthy subjects using O2 and CO2 challenges, was used to validate the approach. The validation conveyed expected estimates of model parameters (e.g., low PmO2), with spatially uniform OEF maps (grey matter, GM, OEF spatial standard deviation ≈ 0.13). GM OEF estimates obtained with hypercapnia calibrated fMRI correlated with dc-fMRI (r = 0.65, p = 2·10-3). For 12 subjects, OEF measured with dc-fMRI and the single gas calibration method were correlated with whole-brain OEF derived from phase measures in the superior sagittal sinus (r = 0.58, p = 0.048; r = 0.64, p = 0.025 respectively). Simplified calibrated fMRI using hypercapnia holds promise for clinical application.
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Affiliation(s)
- Antonio M Chiarelli
- Department of Neuroscience, Imaging, and Clinical Sciences, University G. D'Annunzio of Chieti-Pescara, Chieti, Italy.,Institute for Advanced Biomedical Technologies, University G. D'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Michael Germuska
- Department of Psychology, Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff University, Cardiff, UK
| | - Hannah Chandler
- Department of Psychology, Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff University, Cardiff, UK
| | - Rachael Stickland
- Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Eleonora Patitucci
- Department of Psychology, Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff University, Cardiff, UK
| | - Emma Biondetti
- Department of Neuroscience, Imaging, and Clinical Sciences, University G. D'Annunzio of Chieti-Pescara, Chieti, Italy.,Institute for Advanced Biomedical Technologies, University G. D'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Daniele Mascali
- Department of Neuroscience, Imaging, and Clinical Sciences, University G. D'Annunzio of Chieti-Pescara, Chieti, Italy.,Institute for Advanced Biomedical Technologies, University G. D'Annunzio of Chieti-Pescara, Chieti, Italy
| | - Neeraj Saxena
- Department of Psychology, Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff University, Cardiff, UK
| | - Sharmila Khot
- Department of Psychology, Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff University, Cardiff, UK
| | - Jessica Steventon
- Department of Psychology, Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff University, Cardiff, UK
| | - Catherine Foster
- Wales Institute of Social and Economic Research and Data (WISERD), School of Social Sciences, Cardiff University, Cardiff, UK
| | - Ana E Rodríguez-Soto
- Department of Radiology, University of California, San Diego, La Jolla, California, USA
| | - Erin Englund
- Department of Radiology, University of Colorado, Aurora, Colorado, USA
| | - Kevin Murphy
- Department of Psychology, Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff University, Cardiff, UK
| | - Valentina Tomassini
- Department of Neuroscience, Imaging, and Clinical Sciences, University G. D'Annunzio of Chieti-Pescara, Chieti, Italy.,Institute for Advanced Biomedical Technologies, University G. D'Annunzio of Chieti-Pescara, Chieti, Italy.,Department of Psychology, Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff University, Cardiff, UK.,MS Centre, Dept of Clinical Neurology, SS. Annunziata University Hospital, Chieti, Italy.,Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, UK.,Helen Durham Centre for Neuroinflammation, University Hospital of Wales, Cardiff, UK
| | - Felix W Wehrli
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Richard G Wise
- Department of Neuroscience, Imaging, and Clinical Sciences, University G. D'Annunzio of Chieti-Pescara, Chieti, Italy.,Institute for Advanced Biomedical Technologies, University G. D'Annunzio of Chieti-Pescara, Chieti, Italy.,Department of Psychology, Cardiff University Brain Research Imaging Centre (CUBRIC), Cardiff University, Cardiff, UK
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9
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Giustiniani A, Vallesi A, Oliveri M, Tarantino V, Ambrosini E, Bortoletto M, Masina F, Busan P, Siebner H, Fadiga L, Koch G, Leocani L, Lefaucheur J, Rotenberg A, Zangen A, Violante I, Moliadze V, Gamboa O, Ugawa Y, Pascual-Leone A, Ziemann U, Miniussi C, Burgio F. A questionnaire to collect unintended effects of Transcranial Magnetic Stimulation: A consensus based approach. Clin Neurophysiol 2022; 141:101-108. [DOI: 10.1016/j.clinph.2022.06.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 05/18/2022] [Accepted: 06/10/2022] [Indexed: 11/03/2022]
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10
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Jiang D, Lu H. Cerebral oxygen extraction fraction MRI: Techniques and applications. Magn Reson Med 2022; 88:575-600. [PMID: 35510696 PMCID: PMC9233013 DOI: 10.1002/mrm.29272] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/20/2022] [Accepted: 03/29/2022] [Indexed: 12/20/2022]
Abstract
The human brain constitutes 2% of the body's total mass but uses 20% of the oxygen. The rate of the brain's oxygen utilization can be derived from a knowledge of cerebral blood flow and the oxygen extraction fraction (OEF). Therefore, OEF is a key physiological parameter of the brain's function and metabolism. OEF has been suggested to be a useful biomarker in a number of brain diseases. With recent advances in MRI techniques, several MRI-based methods have been developed to measure OEF in the human brain. These MRI OEF techniques are based on the T2 of blood, the blood signal phase, the magnetic susceptibility of blood-containing voxels, the effect of deoxyhemoglobin on signal behavior in extravascular tissue, and the calibration of the BOLD signal using gas inhalation. Compared to 15 O PET, which is considered the "gold standard" for OEF measurement, MRI-based techniques are non-invasive, radiation-free, and are more widely available. This article provides a review of these emerging MRI-based OEF techniques. We first briefly introduce the role of OEF in brain oxygen homeostasis. We then review the methodological aspects of different categories of MRI OEF techniques, including their signal mechanisms, acquisition methods, and data analyses. The strengths and limitations of the techniques are discussed. Finally, we review key applications of these techniques in physiological and pathological conditions.
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Affiliation(s)
- Dengrong Jiang
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Hanzhang Lu
- The Russell H. Morgan Department of Radiology & Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.,F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Research Institute, Baltimore, Maryland, USA
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11
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Di Pietro M, Russo M, Dono F, Carrarini C, Thomas A, Di Stefano V, Telese R, Bonanni L, Sensi SL, Onofrj M, Franciotti R. A Critical Review of Alien Limb-Related Phenomena and Implications for Functional Magnetic Resonance Imaging Studies. Front Neurol 2021; 12:661130. [PMID: 34566830 PMCID: PMC8458742 DOI: 10.3389/fneur.2021.661130] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 07/06/2021] [Indexed: 11/27/2022] Open
Abstract
Consensus criteria on corticobasal degeneration (CBD) include alien limb (AL) phenomena. However, the gist of the behavioral features of AL is still “a matter of debate.” CBD-related AL has so far included the description of involuntary movements, frontal release phenomena (frontal AL), or asomatognosia (posterior or “real” AL). In this context, the most frequent symptoms are language and praxis deficits and cortical sensory misperception. However, asomatognosia requires, by definition, intact perception and cognition. Thus, to make a proper diagnosis of AL in the context of CBD, cognitive and language dysfunctions must be carefully verified and objectively assessed. We reviewed the current literature on AL in CBD and now propose that the generic use of the term AL should be avoided. This catchall AL term should instead be deconstructed. We propose that the term AL is appropriate to describe clinical features associated with specific brain lesions. More discrete sets of regionally bound clinical signs that depend on dysfunctions of specific brain areas need to be assessed and presented when posing the diagnosis. Thus, in our opinion, the AL term should be employed in association with precise descriptions of the accompanying involuntary movements, sensory misperceptions, agnosia-asomatognosia contents, and the presence of utilization behavior. The review also offers an overview of functional magnetic resonance imaging-based studies evaluating AL-related phenomena. In addition, we provide a complementary set of video clips depicting CBD-related involuntary movements that should not mistakenly be interpreted as signs of AL.
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Affiliation(s)
- Martina Di Pietro
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University, Chieti, Italy
| | - Mirella Russo
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University, Chieti, Italy
| | - Fedele Dono
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University, Chieti, Italy
| | - Claudia Carrarini
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University, Chieti, Italy
| | - Astrid Thomas
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University, Chieti, Italy
| | - Vincenzo Di Stefano
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Department of Biomedicine, Neuroscience and Advanced Diagnostic (BiND), University of Palermo, Palermo, Italy
| | - Roberta Telese
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,IRCCS C. Mondino Foundation, Pavia, Italy
| | - Laura Bonanni
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University, Chieti, Italy
| | - Stefano L Sensi
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University, Chieti, Italy
| | - Marco Onofrj
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy.,Center for Advanced Studies and Technology (CAST), "G. D'Annunzio" University, Chieti, Italy.,YDA Foundation, Institute of Immune Therapy and Advanced Biological Treatment, Pescara, Italy
| | - Raffaella Franciotti
- Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio" University of Chieti-Pescara, Chieti, Italy
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12
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Sleight E, Stringer MS, Marshall I, Wardlaw JM, Thrippleton MJ. Cerebrovascular Reactivity Measurement Using Magnetic Resonance Imaging: A Systematic Review. Front Physiol 2021; 12:643468. [PMID: 33716793 PMCID: PMC7947694 DOI: 10.3389/fphys.2021.643468] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 02/01/2021] [Indexed: 12/27/2022] Open
Abstract
Cerebrovascular reactivity (CVR) magnetic resonance imaging (MRI) probes cerebral haemodynamic changes in response to a vasodilatory stimulus. CVR closely relates to the health of the vasculature and is therefore a key parameter for studying cerebrovascular diseases such as stroke, small vessel disease and dementias. MRI allows in vivo measurement of CVR but several different methods have been presented in the literature, differing in pulse sequence, hardware requirements, stimulus and image processing technique. We systematically reviewed publications measuring CVR using MRI up to June 2020, identifying 235 relevant papers. We summarised the acquisition methods, experimental parameters, hardware and CVR quantification approaches used, clinical populations investigated, and corresponding summary CVR measures. CVR was investigated in many pathologies such as steno-occlusive diseases, dementia and small vessel disease and is generally lower in patients than in healthy controls. Blood oxygen level dependent (BOLD) acquisitions with fixed inspired CO2 gas or end-tidal CO2 forcing stimulus are the most commonly used methods. General linear modelling of the MRI signal with end-tidal CO2 as the regressor is the most frequently used method to compute CVR. Our survey of CVR measurement approaches and applications will help researchers to identify good practice and provide objective information to inform the development of future consensus recommendations.
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Affiliation(s)
- Emilie Sleight
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom
| | - Michael S. Stringer
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom,*Correspondence: Michael S. Stringer
| | - Ian Marshall
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom
| | - Joanna M. Wardlaw
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom
| | - Michael J. Thrippleton
- Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom,UK Dementia Research Institute, Edinburgh, United Kingdom
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13
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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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14
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Acute Effects of Caffeine Intake on Psychological Responses and High-Intensity Exercise Performance. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18020584. [PMID: 33445587 PMCID: PMC7827590 DOI: 10.3390/ijerph18020584] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/23/2020] [Accepted: 01/07/2021] [Indexed: 11/17/2022]
Abstract
OBJECTIVE The aim of this study was to investigate the effects of caffeine supplementation on: (i) psychological responses of subjective vitality and mood; (ii) performance through a Wingate test; and (iii) rate of perceived exertion (RPE) reported after a Wingate test. METHODS Fifteen male participants (22.60 ± 2.16 years) ingested 6 mg·kg-1 of caffeine or placebo (sucrose) supplementation in two experimental sessions. After 60 min from supplement intake, participants fulfilled two questionnaires, which measured subjective vitality and mood state, respectively. Subsequently, participants' performance was assessed through a Wingate test, which was followed by measurements of RPE at general, muscular, or cardiovascular level. RESULTS Caffeine supplementation increased some components of mood, as assessed by profile of mood states (POMS) (tension and vigor dimensions) and subjective vitality profiles, which were followed by a greater maximum power, average power, and lower time needed to reach maximum power during the Wingate test. Moreover, lower RPE, both at muscular and general levels were reported by participants after the Wingate test. CONCLUSIONS These results suggest that caffeine supplementation exerts positive effects both in psychological and physical domains in trained subjects.
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15
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Tsvetanov KA, Henson RNA, Rowe JB. Separating vascular and neuronal effects of age on fMRI BOLD signals. Philos Trans R Soc Lond B Biol Sci 2021; 376:20190631. [PMID: 33190597 PMCID: PMC7741031 DOI: 10.1098/rstb.2019.0631] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/19/2020] [Indexed: 12/14/2022] Open
Abstract
Accurate identification of brain function is necessary to understand the neurobiology of cognitive ageing, and thereby promote well-being across the lifespan. A common tool used to investigate neurocognitive ageing is functional magnetic resonance imaging (fMRI). However, although fMRI data are often interpreted in terms of neuronal activity, the blood oxygenation level-dependent (BOLD) signal measured by fMRI includes contributions of both vascular and neuronal factors, which change differentially with age. While some studies investigate vascular ageing factors, the results of these studies are not well known within the field of neurocognitive ageing and therefore vascular confounds in neurocognitive fMRI studies are common. Despite over 10 000 BOLD-fMRI papers on ageing, fewer than 20 have applied techniques to correct for vascular effects. However, neurovascular ageing is not only a confound in fMRI, but an important feature in its own right, to be assessed alongside measures of neuronal ageing. We review current approaches to dissociate neuronal and vascular components of BOLD-fMRI of regional activity and functional connectivity. We highlight emerging evidence that vascular mechanisms in the brain do not simply control blood flow to support the metabolic needs of neurons, but form complex neurovascular interactions that influence neuronal function in health and disease. This article is part of the theme issue 'Key relationships between non-invasive functional neuroimaging and the underlying neuronal activity'.
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Affiliation(s)
- Kamen A. Tsvetanov
- Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0SZ, UK
- Department of Psychology, University of Cambridge, Cambridge CB2 3EB, UK
| | - Richard N. A. Henson
- Department of Psychiatry, University of Cambridge, Cambridge CB2 0SP, UK
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
| | - James B. Rowe
- Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0SZ, UK
- Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
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16
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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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17
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Sivakolundu DK, West KL, Zuppichini MD, Wilson A, Moog TM, Blinn AP, Newton BD, Wang Y, Stanley T, Guo X, Rypma B, Okuda DT. BOLD signal within and around white matter lesions distinguishes multiple sclerosis and non-specific white matter disease: a three-dimensional approach. J Neurol 2020; 267:2888-2896. [PMID: 32468116 DOI: 10.1007/s00415-020-09923-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 05/12/2020] [Accepted: 05/14/2020] [Indexed: 12/16/2022]
Abstract
Multiple sclerosis (MS) diagnostic criteria are based upon clinical presentation and presence of white matter hyperintensities on two-dimensional magnetic resonance imaging (MRI) views. Such criteria, however, are prone to false-positive interpretations due to the presence of similar MRI findings in non-specific white matter disease (NSWMD) states such as migraine and microvascular disease. The coexistence of age-related changes has also been recognized in MS patients, and this comorbidity further poses a diagnostic challenge. In this study, we investigated the physiologic profiles within and around MS and NSWMD lesions and their ability to distinguish the two disease states. MS and NSWMD lesions were identified using three-dimensional (3D) T2-FLAIR images and segmented using geodesic active contouring. A dual-echo functional MRI sequence permitted near-simultaneous measurement of blood-oxygen-level-dependent signal (BOLD) and cerebral blood flow (CBF). BOLD and CBF were calculated within lesions and in 3D concentric layers surrounding each lesion. BOLD slope, an indicator of lesion metabolic capacity, was calculated as the change in BOLD from a lesion through its surrounding perimeters. We observed sequential BOLD signal reductions from the lesion towards the perimeters for MS, while no such decreases were observed for NSWMD lesions. BOLD slope was significantly lower in MS compared to NSWM lesions, suggesting decreased metabolic activity in MS lesions. Furthermore, BOLD signal within and around lesions significantly distinguished MS and NSWMD lesions. These results suggest that this technique shows promise for clinical utility in distinguishing NSWMD or MS disease states and identifying NSWMD lesions occurring in MS patients.
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Affiliation(s)
- Dinesh K Sivakolundu
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX, USA.,Department of Biological Sciences, University of Texas at Dallas, Dallas, TX, USA
| | - Kathryn L West
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX, USA
| | - Mark D Zuppichini
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX, USA
| | - Andrew Wilson
- Department of Computer Science, University of Texas at Dallas, Dallas, TX, USA
| | - Tatum M Moog
- Neuroinnovation Program, Multiple Sclerosis & Neuroimmunology Imaging Program, Department of Neurology & Neurotherapeutics, UT Southwestern Medical Center, Dallas, TX, USA
| | - Aiden P Blinn
- Neuroinnovation Program, Multiple Sclerosis & Neuroimmunology Imaging Program, Department of Neurology & Neurotherapeutics, UT Southwestern Medical Center, Dallas, TX, USA
| | - Braeden D Newton
- Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Yeqi Wang
- Department of Computer Science, University of Texas at Dallas, Dallas, TX, USA
| | - Thomas Stanley
- Department of Computer Science, University of Texas at Dallas, Dallas, TX, USA
| | - Xiaohu Guo
- Department of Computer Science, University of Texas at Dallas, Dallas, TX, USA
| | - Bart Rypma
- School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX, USA.,Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX, USA
| | - Darin T Okuda
- Neuroinnovation Program, Multiple Sclerosis & Neuroimmunology Imaging Program, Department of Neurology & Neurotherapeutics, UT Southwestern Medical Center, Dallas, TX, USA.
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18
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Germuska M, Chandler H, Okell T, Fasano F, Tomassini V, Murphy K, Wise R. A frequency-domain machine learning method for dual-calibrated fMRI mapping of oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen consumption (CMRO 2). Front Artif Intell 2020; 3. [PMID: 32885165 PMCID: PMC7116003 DOI: 10.3389/frai.2020.00012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Magnetic resonance imaging (MRI) offers the possibility to non-invasively map the brain's metabolic oxygen consumption (CMRO2), which is essential for understanding and monitoring neural function in both health and disease. However, in depth study of oxygen metabolism with MRI has so far been hindered by the lack of robust methods. One MRI method of mapping CMRO2 is based on the simultaneous acquisition of cerebral blood flow (CBF) and blood oxygen level dependent (BOLD) weighted images during respiratory modulation of both oxygen and carbon dioxide. Although this dual-calibrated methodology has shown promise in the research setting, current analysis methods are unstable in the presence of noise and/or are computationally demanding. In this paper, we present a machine learning implementation for the multi-parametric assessment of dual-calibrated fMRI data. The proposed method aims to address the issues of stability, accuracy, and computational overhead, removing significant barriers to the investigation of oxygen metabolism with MRI. The method utilizes a time-frequency transformation of the acquired perfusion and BOLD-weighted data, from which appropriate feature vectors are selected for training of machine learning regressors. The implemented machine learning methods are chosen for their robustness to noise and their ability to map complex non-linear relationships (such as those that exist between BOLD signal weighting and blood oxygenation). An extremely randomized trees (ET) regressor is used to estimate resting blood flow and a multi-layer perceptron (MLP) is used to estimate CMRO2 and the oxygen extraction fraction (OEF). Synthetic data with additive noise are used to train the regressors, with data simulated to cover a wide range of physiologically plausible parameters. The performance of the implemented analysis method is compared to published methods both in simulation and with in-vivo data (n = 30). The proposed method is demonstrated to significantly reduce computation time, error, and proportional bias in both CMRO2 and OEF estimates. The introduction of the proposed analysis pipeline has the potential to not only increase the detectability of metabolic difference between groups of subjects, but may also allow for single subject examinations within a clinical context.
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Affiliation(s)
- Michael Germuska
- CUBRIC, Department of Psychology, Cardiff University, Cardiff, United Kingdom
| | - Hannah Chandler
- CUBRIC, Department of Psychology, Cardiff University, Cardiff, United Kingdom
| | - Thomas Okell
- Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, United Kingdom
| | | | - Valentina Tomassini
- CUBRIC, Department of Psychology, Cardiff University, Cardiff, United Kingdom.,Division of Psychological Medicine and Clinical Neurosciences, Cardiff University School of Medicine, Cardiff, United Kingdom.,Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio University" of Chieti-Pescara, 66100, Chieti, Italy
| | - Kevin Murphy
- CUBRIC, Department of Psychology, Cardiff University, Cardiff, United Kingdom
| | - Richard Wise
- CUBRIC, Department of Psychology, Cardiff University, Cardiff, United Kingdom.,Department of Neuroscience, Imaging and Clinical Sciences, "G. D'Annunzio University" of Chieti-Pescara, 66100, Chieti, Italy.,Institute for Advanced Biomedical Technologies, "G. D'Annunzio University" of Chieti-Pescara, 66100, Chieti, Italy
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19
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Saxena N, Gili T, Diukova A, Huckle D, Hall JE, Wise RG. Mild Propofol Sedation Reduces Frontal Lobe and Thalamic Cerebral Blood Flow: An Arterial Spin Labeling Study. Front Physiol 2019; 10:1541. [PMID: 31920729 PMCID: PMC6930185 DOI: 10.3389/fphys.2019.01541] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Accepted: 12/05/2019] [Indexed: 01/31/2023] Open
Abstract
Mechanisms of anesthetic drug-induced sedation and unconsciousness are still incompletely understood. Functional neuroimaging modalities provide a window to study brain function changes during anesthesia allowing us to explore the sequence of neuro-physiological changes associated with anesthesia. Cerebral perfusion change under an assumption of intact neurovascular coupling is an indicator of change in large-scale neural activity. In this experiment, we have investigated resting state cerebral blood flow (CBF) changes in the human brain during mild sedation, with propofol. Arterial spin labeling (ASL) provides a non-invasive, reliable, and robust means of measuring cerebral blood flow (CBF) and can therefore be used to investigate central drug effects. Mild propofol sedation-related CBF changes were studied at rest (n = 15), in a 3 T MR scanner using a PICORE-QUIPSS II ASL technique. CBF was reduced in bilateral paracingulate cortex, premotor cortex, Broca's areas, right superior frontal gyrus and also the thalamus. This cerebral perfusion study demonstrates that propofol induces suppression of key cortical (frontal lobe) and subcortical (thalamus) regions during mild sedation.
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Affiliation(s)
- Neeraj Saxena
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom.,Department of Anaesthetics, Intensive Care and Pain Medicine, Cwm Taf Morgannwg University Health Board, Llantrisant, United Kingdom
| | - Tommaso Gili
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom.,IMT School for Advanced Studies Lucca, Lucca, Italy
| | - Ana Diukova
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom
| | - Danielle Huckle
- Department of Anaesthetics, University Hospital of Wales, Cardiff, United Kingdom
| | - Judith E Hall
- Department of Anaesthetics, Intensive Care and Pain Medicine, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Richard G Wise
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom
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Boukrina O, Kucukboyaci NE, Dobryakova E. Considerations of power and sample size in rehabilitation research. Int J Psychophysiol 2019; 154:6-14. [PMID: 31655185 DOI: 10.1016/j.ijpsycho.2019.08.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Revised: 05/22/2019] [Accepted: 08/23/2019] [Indexed: 01/26/2023]
Abstract
With the current emphasis on power and reproducibility, pressures are rising to increase sample sizes in rehabilitation research in order to reflect more accurate effect estimation and generalizable results. The conventional way of increasing power by enrolling more participants is less feasible in some fields of research. In particular, rehabilitation research faces considerable challenges in achieving this goal. We describe the specific challenges to increasing power by recruiting large sample sizes and obtaining large effects in rehabilitation research. Specifically, we discuss how variability within clinical populations, lack of common standards for selecting appropriate control groups; potentially reduced reliability of measurements of brain function in individuals recovering from a brain injury; biases involved in a priori effect size estimation, and higher budgetary and staffing requirements can influence considerations of sample and effect size in rehabilitation. We also describe solutions to these challenges, such as increased sampling per participant, improving experimental control, appropriate analyses, transparent result reporting and using innovative ways of harnessing the inherent variability of clinical populations. These solutions can improve statistical power and produce reliable and valid results even in the face of limited availability of large samples.
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Affiliation(s)
- Olga Boukrina
- Center for Stroke Rehabilitation Research, Kessler Foundation, West Orange, NJ, USA; Department of Physical Medicine and Rehabilitation, Rutgers-New Jersey Medical School, Newark, NJ, USA
| | - N Erkut Kucukboyaci
- Center for Traumatic Brain Injury Research, Kessler Foundation, East Hanover, NJ, USA; Department of Physical Medicine and Rehabilitation, Rutgers-New Jersey Medical School, Newark, NJ, USA
| | - Ekaterina Dobryakova
- Center for Traumatic Brain Injury Research, Kessler Foundation, East Hanover, NJ, USA; Department of Physical Medicine and Rehabilitation, Rutgers-New Jersey Medical School, Newark, NJ, USA.
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21
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Yang Y, Yin Y, Lu J, Zou Q, Gao JH. Detecting resting-state brain activity using OEF-weighted imaging. Neuroimage 2019; 200:101-120. [PMID: 31228637 DOI: 10.1016/j.neuroimage.2019.06.038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 06/03/2019] [Accepted: 06/17/2019] [Indexed: 01/17/2023] Open
Abstract
Traditional resting-state functional magnetic resonance imaging (fMRI) is mainly based on the blood oxygenation level-dependent (BOLD) contrast. The oxygen extraction fraction (OEF) represents an important parameter of brain metabolism and is a key biomarker of tissue viability, detecting the ratio of oxygen utilization to oxygen delivery. Investigating spontaneous fluctuations in the OEF-weighted signal is crucial for understanding the underlying mechanism of brain activity because of the immense energy budget during the resting state. However, due to the poor temporal resolution of OEF mapping, no studies have reported using OEF contrast to assess resting-state brain activity. In this fMRI study, we recorded brain OEF-weighted fluctuations for 10 min in healthy volunteers across two scanning visits, using our recently developed pulse sequence that can acquire whole-brain voxel-wise OEF-weighted signals with a temporal resolution of 3 s. Using both group-independent component analysis and seed-based functional connectivity analysis, we robustly identified intrinsic brain networks, including the medial visual, lateral visual, auditory, default mode and bilateral executive control networks, using OEF contrast. Furthermore, we investigated the resting-state local characteristics of brain activity based on OEF-weighted signals using regional homogeneity (ReHo) and fractional amplitude of low-frequency fluctuations (fALFF). We demonstrated that the gray matter regions of the brain, especially those in the default mode network, showed higher ReHo and fALFF values with the OEF contrast. Moreover, voxel-wise test-retest reliability comparisons across the whole brain demonstrated that the reliability of resting-state brain activity based on the OEF contrast was moderate for the network indices and high for the local activity indices, especially for ReHo. Although the reliabilities of the OEF-based indices were generally lower than those based on BOLD, the reliability of OEF-ReHo was slightly higher than that of BOLD-ReHo, with a small effect size, which indicated that OEF-ReHo could be used as a reliable index for characterizing resting-state local brain activity as a complement to BOLD. In conclusion, OEF can be used as an effective contrast to study resting-state brain activity with a medium to high test-retest reliability.
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Affiliation(s)
- Yang Yang
- Beijing City Key Lab for Medical Physics and Engineering, Institution of Heavy Ion Physics, School of Physics, Peking University, Beijing, 100871, China; Center for MRI Research, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China
| | - Yayan Yin
- Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China; Beijing Key Laboratory of Magnetic Resonance Imaging and Brain Informatics, Beijing, 100053, China
| | - Jie Lu
- Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing, 100053, China; Beijing Key Laboratory of Magnetic Resonance Imaging and Brain Informatics, Beijing, 100053, China.
| | - Qihong Zou
- Center for MRI Research, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China.
| | - Jia-Hong Gao
- Beijing City Key Lab for Medical Physics and Engineering, Institution of Heavy Ion Physics, School of Physics, Peking University, Beijing, 100871, China; Center for MRI Research, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China; McGovern Institute for Brain Research, Peking University, Beijing, 100871, China; Shenzhen Key Laboratory of Affective and Social Cognitive Science, Institute of Affective and Social Neuroscience, Shenzhen University, Shenzhen, 518060, China; Shenzhen Institute of Neuroscience, Shenzhen, 518057, China.
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22
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Schrantee A, Solleveld MM, Schwantje H, Bruin WB, Mutsaerts HJMM, Adriaanse SM, Lucassen P, Booij J, Reneman L. Dose-dependent effects of the selective serotonin reuptake inhibitor citalopram: A combined SPECT and phMRI study. J Psychopharmacol 2019; 33:660-669. [PMID: 30887865 PMCID: PMC6572584 DOI: 10.1177/0269881119836229] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND Serotonin transporter blockers, like citalopram, dose-dependently bind to the serotonin transporter. Pharmacological magnetic resonance imaging (phMRI) can be used to non-invasively monitor effects of serotonergic medication. Although previous studies showed that phMRI can measure the effect of a single dose of serotoninergic medication, it is currently unclear whether it can also detect dose-dependent effects. AIMS To investigate the dose-dependent phMRI response to citalopram and compared this with serotonin transporter occupancy, measured with single photon emission computed tomography (SPECT). METHODS Forty-five healthy females were randomized to pre-treatment with placebo, a low (4 mg) or clinically standard (16 mg) oral citalopram dose. Prior to citalopram, and 3 h after, subjects underwent SPECT scanning. Subsequently, a phMRI scan with a citalopram challenge (7.5 mg intravenously) was conducted. Change in cerebral blood flow in response to the citalopram challenge was assessed in the thalamus and occipital cortex (control region). RESULTS Citalopram dose-dependently affected serotonin transporter occupancy, as measured with SPECT. In addition, citalopram dose-dependently affected the phMRI response to intravenous citalopram in the thalamus (but not occipital cortex), but phMRI was less sensitive in distinguishing between groups than SPECT. Serotonin transporter occupancy showed a trend-significant correlation to thalamic cerebral blood flow change. CONCLUSION These results suggest that phMRI likely suffers from higher variation than SPECT, but that these techniques probably also assess different functional aspects of the serotonergic synapse; therefore phMRI could complement positron emission tomography/SPECT for measuring effects of serotonergic medication.
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Affiliation(s)
- Anouk Schrantee
- Amsterdam University Medical Centers, Academic Medical Center, Department of Radiology and Nuclear Medicine, Amsterdam, The Netherlands,Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands,A Schrantee, Amsterdam University Medical Centers, Academic Medical Center, Department of Radiology and Nuclear Medicine, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands.
| | - Michelle M Solleveld
- Amsterdam University Medical Centers, Academic Medical Center, Department of Radiology and Nuclear Medicine, Amsterdam, The Netherlands,Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Hilde Schwantje
- Amsterdam University Medical Centers, Academic Medical Center, Department of Radiology and Nuclear Medicine, Amsterdam, The Netherlands
| | - Willem B Bruin
- Amsterdam University Medical Centers, Academic Medical Center, Department of Psychiatry, Amsterdam, The Netherlands
| | - Henk-Jan MM Mutsaerts
- Amsterdam University Medical Centers, Academic Medical Center, Department of Radiology and Nuclear Medicine, Amsterdam, The Netherlands
| | - Sofie M Adriaanse
- Amsterdam University Medical Centers, Academic Medical Center, Department of Radiology and Nuclear Medicine, Amsterdam, The Netherlands
| | - Paul Lucassen
- Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Jan Booij
- Amsterdam University Medical Centers, Academic Medical Center, Department of Radiology and Nuclear Medicine, Amsterdam, The Netherlands
| | - Liesbeth Reneman
- Amsterdam University Medical Centers, Academic Medical Center, Department of Radiology and Nuclear Medicine, Amsterdam, The Netherlands
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23
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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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24
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Sivakolundu DK, Hansen MR, West KL, Wang Y, Stanley T, Wilson A, McCreary M, Turner MP, Pinho MC, Newton BD, Guo X, Rypma B, Okuda DT. Three‐Dimensional Lesion Phenotyping and Physiologic Characterization Inform Remyelination Ability in Multiple Sclerosis. J Neuroimaging 2019; 29:605-614. [DOI: 10.1111/jon.12633] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 05/11/2019] [Accepted: 05/13/2019] [Indexed: 11/29/2022] Open
Affiliation(s)
- Dinesh K. Sivakolundu
- NeuroPsychometric Research Laboratory, Center for BrainHealthUniversity of Texas at Dallas Dallas TX
| | - Madison R. Hansen
- Department of Neurology & NeurotherapeuticsUT Southwestern Medical Center Dallas TX
| | - Kathryn L. West
- NeuroPsychometric Research Laboratory, Center for BrainHealthUniversity of Texas at Dallas Dallas TX
| | - Yeqi Wang
- Department of Computer ScienceUniversity of Texas at Dallas Dallas TX
| | - Thomas Stanley
- Department of Computer ScienceUniversity of Texas at Dallas Dallas TX
| | - Andrew Wilson
- Department of Computer ScienceUniversity of Texas at Dallas Dallas TX
| | | | - Monroe P. Turner
- NeuroPsychometric Research Laboratory, Center for BrainHealthUniversity of Texas at Dallas Dallas TX
| | - Marco C. Pinho
- Department of RadiologyUT Southwestern Medical Center Dallas TX
| | | | - Xiaohu Guo
- Department of Computer ScienceUniversity of Texas at Dallas Dallas TX
| | - Bart Rypma
- NeuroPsychometric Research Laboratory, Center for BrainHealthUniversity of Texas at Dallas Dallas TX
- Department of PsychiatryUT Southwestern Medical Center Dallas TX
| | - Darin T. Okuda
- Department of Neurology & NeurotherapeuticsUT Southwestern Medical Center Dallas TX
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25
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Franco-Alvarenga PE, Brietzke C, Canestri R, Goethel MF, Hettinga F, Santos TM, Pires FO. Caffeine improved cycling trial performance in mentally fatigued cyclists, regardless of alterations in prefrontal cortex activation. Physiol Behav 2019; 204:41-48. [DOI: 10.1016/j.physbeh.2019.02.009] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 02/08/2019] [Accepted: 02/08/2019] [Indexed: 10/27/2022]
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26
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The association of coffee consumption and oxygen desaturation index during sleep among Japanese male workers. Sleep Breath 2019; 23:1027-1031. [PMID: 30806944 DOI: 10.1007/s11325-019-01815-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 01/27/2019] [Accepted: 02/19/2019] [Indexed: 10/27/2022]
Abstract
BACKGROUND AND OBJECTIVE Coffee is a major caffeine-containing food source that can be used for treatment of apnea in prematurity. However, few studies have examined the association between coffee consumption and sleep-disordered breathing (SDB). We investigated whether coffee consumption is associated with the oxygen desaturation index (ODI) as a marker of SDB among middle-aged Japanese male workers. METHODS The subjects were 1126 male local government workers aged 22-59 who participated in SDB screening in 2011-2012. Daily coffee consumption was assessed by a self-administered questionnaire. We measured 3% oxygen desaturation (3%ODI) during a night's sleep using a pulse oximeter. A general linear model was used to calculate the multivariate-adjusted means of 3%ODI per quartile of coffee consumption. We further analyzed the data after stratifying by overweight and current smoking status. RESULTS A inverse association between coffee consumption and 3%ODI was found. The multivariate-adjusted mean of 3%ODI for the lowest and highest coffee consumption groups were 11.9 times/h and 10.6 times/h (p for trend = 0.06), respectively; 14.6 and 11.5 times/h (p for trend = 0.01) in overweight participants; and 12.7 and 11.0 times/h (p for trend = 0.06) in non-smokers. No associations were found in non-overweight and smoking workers. CONCLUSIONS Our results suggest that higher coffee consumption was associated with lower 3% ODI as a marker of SDB in overweight and non-smoking workers.
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27
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Yang HCS, Liang Z, Yao JF, Shen X, Frederick BD, Tong Y. Vascular effects of caffeine found in BOLD fMRI. J Neurosci Res 2018; 97:456-466. [PMID: 30488978 DOI: 10.1002/jnr.24360] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 11/08/2018] [Accepted: 11/08/2018] [Indexed: 11/11/2022]
Abstract
The blood oxygen level-dependent (BOLD) signal in functional magnetic resonance imaging (fMRI) measures neuronal activation indirectly. Previous studies have found aperiodic, systemic low-frequency oscillations (sLFOs, ~0.1 Hz) in BOLD signals from resting state (RS) fMRI, which reflects the non-neuronal cerebral perfusion information. In this study, we investigated the possibility of extracting vascular information from the sLFOs in RS BOLD fMRI, which could provide complementary information to the neuronal activations. Two features of BOLD signals were exploited. First, time delays between the sLFOs of big blood vessels and brain voxels were calculated to determine cerebral circulation times and blood arrival times. Second, voxel-wise standard deviations (SD) of LFOs were calculated to represent the blood densities. We explored those features on the publicly available Myconnectome data set (a 2-year study of an individual subject (Male)), which contains 45 RS scans acquired after the subject had coffee, and 45 coffee-free RS scans, acquired on different days. Our results showed that shorter time delays and smaller SDs were detected in caffeinated scans. This is consistent with the vasoconstriction effects of caffeine, which leads to increased blood flow velocity. We also compared our results with previous findings on neuronal networks from the same data set. Our finding showed that brain regions with the significant vascular effect of caffeine coincide with those with a significant neuronal effect, indicating close interaction. This study provides methods to assess the physiological information from RS fMRI. Together with the neuronal information, we can study simultaneously the underlying correlations and interactions between vascular and neuronal networks, especially in pharmacological studies.
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Affiliation(s)
- Ho-Ching Shawn Yang
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana
| | - Zhenhu Liang
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana.,Institute of Electrical Engineering, Yanshan University, Qinhuangdao, China
| | - Jinxia Fiona Yao
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana
| | - Xin Shen
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana
| | - Blaise deB Frederick
- McLean Imaging Center, McLean Hospital, Belmont, Massachusetts.,Department of Psychiatry, Harvard Medical School, Boston, Massachusetts
| | - Yunjie Tong
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana
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28
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Merola A, Germuska MA, Murphy K, Wise RG. Assessing the repeatability of absolute CMRO 2, OEF and haemodynamic measurements from calibrated fMRI. Neuroimage 2018; 173:113-126. [PMID: 29454105 PMCID: PMC6503182 DOI: 10.1016/j.neuroimage.2018.02.020] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 01/12/2018] [Accepted: 02/12/2018] [Indexed: 12/27/2022] Open
Abstract
As energy metabolism in the brain is largely oxidative, the measurement of cerebral metabolic rate of oxygen consumption (CMRO2) is a desirable biomarker for quantifying brain activity and tissue viability. Currently, PET techniques based on oxygen isotopes are the gold standard for obtaining whole brain CMRO2 maps. Among MRI techniques that have been developed as an alternative are dual calibrated fMRI (dcFMRI) methods, which exploit simultaneous measurements of BOLD and ASL signals during a hypercapnic-hyperoxic experiment to modulate brain blood flow and oxygenation. In this study we quantified the repeatability of a dcFMRI approach developed in our lab, evaluating its limits and informing its application in studies aimed at characterising the metabolic state of human brain tissue over time. Our analysis focussed on the estimates of oxygen extraction fraction (OEF), cerebral blood flow (CBF), CBF-related cerebrovascular reactivity (CVR) and CMRO2 based on a forward model that describes analytically the acquired dual echo GRE signal. Indices of within- and between-session repeatability are calculated from two different datasets both at a bulk grey matter and at a voxel-wise resolution and finally compared with similar indices obtained from previous MRI and PET measurements. Within- and between-session values of intra-subject coefficient of variation (CVintra) calculated from bulk grey matter estimates 6.7 ± 6.6% (mean ± std.) and 10.5 ± 9.7% for OEF, 6.9 ± 6% and 5.5 ± 4.7% for CBF, 12 ± 9.7% and 12.3 ± 10% for CMRO2. Coefficient of variation (CV) and intraclass correlation coefficient (ICC) maps showed the spatial distribution of the repeatability metrics, informing on the feasibility limits of the method. In conclusion, results show an overall consistency of the estimated physiological parameters with literature reports and a satisfactory level of repeatability considering the higher spatial sensitivity compared to other MRI methods, with varied performance depending on the specific parameter under analysis, on the spatial resolution considered and on the study design.
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Affiliation(s)
- Alberto Merola
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, UK; Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, DE, Germany
| | - Michael A Germuska
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, UK
| | - Kevin Murphy
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Physics and Astronomy, Cardiff University, UK
| | - Richard G Wise
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff University, UK.
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29
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Joris PJ, Mensink RP, Adam TC, Liu TT. Cerebral Blood Flow Measurements in Adults: A Review on the Effects of Dietary Factors and Exercise. Nutrients 2018; 10:nu10050530. [PMID: 29693564 PMCID: PMC5986410 DOI: 10.3390/nu10050530] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 04/11/2018] [Accepted: 04/23/2018] [Indexed: 12/22/2022] Open
Abstract
Improving cerebrovascular function may be a key mechanism whereby a healthy lifestyle, of which a healthy diet combined with increased physical activity levels is a cornerstone, protects against cognitive impairments. In this respect, effects on cerebral blood flow (CBF)—a sensitive physiological marker of cerebrovascular function—are of major interest. This review summarizes the impact of specific dietary determinants and physical exercise on CBF in adults and discusses the relation between these effects with potential changes in cognitive function. A limited number of randomized controlled trials have already demonstrated the beneficial effects of an acute intake of nitrate and polyphenols on CBF, but evidence for a relationship between these effects as well as improvements in cognitive functioning is limited. Moreover, long-term trans-resveratrol supplementation has been shown to increase CBF in populations at increased risk of accelerated cognitive decline. Long-term supplementation of n-3 long-chain polyunsaturated fatty acids may also increase CBF, but related effects on cognitive performance have not yet been found. Significant decreases in cerebral perfusion were observed by commonly consumed amounts of caffeine, while alcohol intake was shown to increase CBF in a dose-dependent way. However, the long-term effects are not clear. Finally, long-term exercise training may be a promising approach to improve CBF, as increases in perfusion may contribute to the beneficial effects on cognitive functioning observed following increased physical activity levels.
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Affiliation(s)
- Peter J Joris
- Department of Nutrition and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, 6200 MD Maastricht, The Netherlands.
| | - Ronald P Mensink
- Department of Nutrition and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, 6200 MD Maastricht, The Netherlands.
| | - Tanja C Adam
- Department of Nutrition and Movement Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, 6200 MD Maastricht, The Netherlands.
| | - Thomas T Liu
- Center for Functional Magnetic Resonance Imaging (MRI), University of California San Diego, La Jolla, CA 92093-0677, USA.
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30
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Germuska M, Wise RG. Calibrated fMRI for mapping absolute CMRO 2: Practicalities and prospects. Neuroimage 2018; 187:145-153. [PMID: 29605580 DOI: 10.1016/j.neuroimage.2018.03.068] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 03/14/2018] [Accepted: 03/28/2018] [Indexed: 01/21/2023] Open
Abstract
Functional magnetic resonance imaging (fMRI) is an essential workhorse of modern neuroscience, providing valuable insight into the functional organisation of the brain. The physiological mechanisms underlying the blood oxygenation level dependent (BOLD) effect are complex and preclude a straightforward interpretation of the signal. However, by employing appropriate calibration of the BOLD signal, quantitative measurements can be made of important physiological parameters including the absolute rate of cerebral metabolic oxygen consumption or oxygen metabolism (CMRO2) and oxygen extraction (OEF). The ability to map such fundamental parameters has the potential to greatly expand the utility of fMRI and to broaden its scope of application in clinical research and clinical practice. In this review article we discuss some of the practical issues related to the calibrated-fMRI approach to the measurement of CMRO2. We give an overview of the necessary precautions to ensure high quality data acquisition, and explore some of the pitfalls and challenges that must be considered as it is applied and interpreted in a widening array of diseases and research questions.
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Affiliation(s)
- M Germuska
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Maindy Road, CF24 4HQ, Cardiff, UK
| | - R G Wise
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Maindy Road, CF24 4HQ, Cardiff, UK.
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31
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Liu P, De Vis JB, Lu H. Cerebrovascular reactivity (CVR) MRI with CO2 challenge: A technical review. Neuroimage 2018; 187:104-115. [PMID: 29574034 DOI: 10.1016/j.neuroimage.2018.03.047] [Citation(s) in RCA: 136] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 02/06/2018] [Accepted: 03/19/2018] [Indexed: 11/16/2022] Open
Abstract
Cerebrovascular reactivity (CVR) is an indicator of cerebrovascular reserve and provides important information about vascular health in a range of brain conditions and diseases. Unlike steady-state vascular parameters, such as cerebral blood flow (CBF) and cerebral blood volume (CBV), CVR measures the ability of cerebral vessels to dilate or constrict in response to challenges or maneuvers. Therefore, CVR mapping requires a physiological challenge while monitoring the corresponding hemodynamic changes in the brain. The present review primarily focuses on methods that use CO2 inhalation as a physiological challenge while monitoring changes in hemodynamic MRI signals. CO2 inhalation has been increasingly used in CVR mapping in recent literature due to its potency in causing vasodilation, rapid onset and cessation of the effect, as well as advances in MRI-compatible gas delivery apparatus. In this review, we first discuss the physiological basis of CVR mapping using CO2 inhalation. We then review the methodological aspects of CVR mapping, including gas delivery apparatus, the timing paradigm of the breathing challenge, the MRI imaging sequence, and data analysis. In addition, we review alternative approaches for CVR mapping that do not require CO2 inhalation.
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Affiliation(s)
- Peiying Liu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, United States.
| | - Jill B De Vis
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, United States
| | - Hanzhang Lu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, United States; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, 21287, United States; F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD, 21205, United States
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32
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Bright MG, Croal PL, Blockley NP, Bulte DP. Multiparametric measurement of cerebral physiology using calibrated fMRI. Neuroimage 2017; 187:128-144. [PMID: 29277404 DOI: 10.1016/j.neuroimage.2017.12.049] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 12/14/2017] [Accepted: 12/15/2017] [Indexed: 02/07/2023] Open
Abstract
The ultimate goal of calibrated fMRI is the quantitative imaging of oxygen metabolism (CMRO2), and this has been the focus of numerous methods and approaches. However, one underappreciated aspect of this quest is that in the drive to measure CMRO2, many other physiological parameters of interest are often acquired along the way. This can significantly increase the value of the dataset, providing greater information that is clinically relevant, or detail that can disambiguate the cause of signal variations. This can also be somewhat of a double-edged sword: calibrated fMRI experiments combine multiple parameters into a physiological model that requires multiple steps, thereby providing more opportunity for error propagation and increasing the noise and error of the final derived values. As with all measurements, there is a trade-off between imaging time, spatial resolution, coverage, and accuracy. In this review, we provide a brief overview of the benefits and pitfalls of extracting multiparametric measurements of cerebral physiology through calibrated fMRI experiments.
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Affiliation(s)
- Molly G Bright
- Sir Peter Mansfield Imaging Centre, School of Medicine, University of Nottingham, Nottingham, UK; Department of Physical Therapy and Human Movement Sciences, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Paula L Croal
- IBME, Department of Engineering Science, University of Oxford, Oxford, UK
| | - Nicholas P Blockley
- FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Daniel P Bulte
- IBME, Department of Engineering Science, University of Oxford, Oxford, UK; FMRIB, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
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Thompson GJ. Neural and metabolic basis of dynamic resting state fMRI. Neuroimage 2017; 180:448-462. [PMID: 28899744 DOI: 10.1016/j.neuroimage.2017.09.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Revised: 08/30/2017] [Accepted: 09/06/2017] [Indexed: 02/07/2023] Open
Abstract
Resting state fMRI (rsfMRI) as a technique showed much initial promise for use in psychiatric and neurological diseases where diagnosis and treatment were difficult. To realize this promise, many groups have moved towards examining "dynamic rsfMRI," which relies on the assumption that rsfMRI measurements on short time scales remain relevant to the underlying neural and metabolic activity. Many dynamic rsfMRI studies have demonstrated differences between clinical or behavioral groups beyond what static rsfMRI measured, suggesting a neurometabolic basis. Correlative studies combining dynamic rsfMRI and other physiological measurements have supported this. However, they also indicate multiple mechanisms and, if using correlation alone, it is difficult to separate cause and effect. Hypothesis-driven studies are needed, a few of which have begun to illuminate the underlying neurometabolic mechanisms that shape observed differences in dynamic rsfMRI. While the number of potential noise sources, potential actual neurometabolic sources, and methodological considerations can seem overwhelming, dynamic rsfMRI provides a rich opportunity in systems neuroscience. Even an incrementally better understanding of the neurometabolic basis of dynamic rsfMRI would expand rsfMRI's research and clinical utility, and the studies described herein take the first steps on that path forward.
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Affiliation(s)
- Garth J Thompson
- iHuman Institute, ShanghaiTech University, Shanghai 201210, China.
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