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Arshad MF, Walkinshaw E, Solomon AL, Bernjak A, Rombach I, Little SA, Shaw JAM, Heller SR, Iqbal A. Diabetic autonomic neuropathy does not impede improvement in hypoglycaemia awareness in adults: Sub-study results from the HypoCOMPaSS trial. Diabet Med 2024:e15340. [PMID: 38741266 DOI: 10.1111/dme.15340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 03/22/2024] [Accepted: 04/17/2024] [Indexed: 05/16/2024]
Abstract
AIMS Impaired awareness of hypoglycaemia (IAH) increases the risk of severe hypoglycaemia in people with type 1 diabetes mellitus (T1DM). IAH can be reversed through meticulous avoidance of hypoglycaemia. Diabetic autonomic neuropathy (DAN) has been proposed as an underlying mechanism contributing to IAH; however, data are inconsistent. The aim of this study was to examine the effects of cardiac autonomic neuropathy (CAN) on IAH reversibility inT1DM. METHODS Participants with T1DM and IAH (Gold score ≥4) recruited to the HypoCOMPaSS (24-week 2 × 2 factorial randomised controlled) trial were included. All underwent screening for cardiac autonomic function testing at baseline and received comparable education and support aimed at avoiding hypoglycaemia and improving hypoglycaemia awareness. Definite CAN was defined as the presence of ≥2 abnormal cardiac reflex tests. Participants were grouped according to their CAN status, and changes in Gold score were compared. RESULTS Eighty-three participants (52 women [62.7%]) were included with mean age (SD) of 48 (12) years and mean HbA1c of 66 (13) mmol/mol (8.2 [3.3] %). The mean duration of T1DM was 29 (13) years. The prevalence of CAN was low with 5/83 (6%) participants having definite autonomic neuropathy with 11 (13%) classified with possible/early neuropathy. All participants, regardless of the autonomic function status, showed a mean improvement in Gold score of ≥1 (mean improvement -1.2 [95% CI -0.8, -1.6]; p < 0.001). CONCLUSIONS IAH can be improved in people with T1DM, and a long duration of disease, with and without cardiac autonomic dysfunction. These data suggest that CAN is not a prime driver for modulating IAH reversibility.
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Affiliation(s)
- Muhammad Fahad Arshad
- University of Sheffield, Sheffield, UK
- Sheffield Teaching Hospitals, NHS Foundation Trust, Sheffield, UK
| | - Emma Walkinshaw
- University of Sheffield, Sheffield, UK
- Sheffield Teaching Hospitals, NHS Foundation Trust, Sheffield, UK
| | | | | | | | - Stuart A Little
- Institute of Cellular Medicine, Newcastle University, Newcastle, UK
- Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle, UK
| | - James A M Shaw
- Institute of Cellular Medicine, Newcastle University, Newcastle, UK
- Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle, UK
| | - Simon R Heller
- University of Sheffield, Sheffield, UK
- Sheffield Teaching Hospitals, NHS Foundation Trust, Sheffield, UK
| | - Ahmed Iqbal
- University of Sheffield, Sheffield, UK
- Sheffield Teaching Hospitals, NHS Foundation Trust, Sheffield, UK
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2
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Chambers ME, Nuibe EH, Reno-Bernstein CM. Brain Regulation of Cardiac Function during Hypoglycemia. Metabolites 2023; 13:1089. [PMID: 37887414 PMCID: PMC10608630 DOI: 10.3390/metabo13101089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/02/2023] [Accepted: 10/16/2023] [Indexed: 10/28/2023] Open
Abstract
Hypoglycemia occurs frequently in people with type 1 and type 2 diabetes. Hypoglycemia activates the counter-regulatory response. Besides peripheral glucose sensors located in the pancreas, mouth, gastrointestinal tract, portal vein, and carotid body, many brain regions also contain glucose-sensing neurons that detect this fall in glucose. The autonomic nervous system innervates the heart, and during hypoglycemia, can cause many changes. Clinical and animal studies have revealed changes in electrocardiograms during hypoglycemia. Cardiac repolarization defects (QTc prolongation) occur during moderate levels of hypoglycemia. When hypoglycemia is severe, it can be fatal. Cardiac arrhythmias are thought to be the major mediator of sudden death due to severe hypoglycemia. Both the sympathetic and parasympathetic nervous systems of the brain have been implicated in regulating these arrhythmias. Besides cardiac arrhythmias, hypoglycemia can have profound changes in the heart and most of these changes are exacerbated in the setting of diabetes. A better understanding of how the brain regulates cardiac changes during hypoglycemia will allow for better therapeutic intervention to prevent cardiovascular death associated with hypoglycemia in people with diabetes. The aim of this paper is to provide a narrative review of what is known in the field regarding how the brain regulates the heart during hypoglycemia.
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Affiliation(s)
| | | | - Candace M. Reno-Bernstein
- Division of Endocrinology, Metabolism, and Diabetes, University of Utah School of Medicine, Salt Lake City, UT 84112, USA (E.H.N.)
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3
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Tran The J, Ansermet JP, Magistretti PJ, Ansermet F. Hyperactivity of the default mode network in schizophrenia and free energy: A dialogue between Freudian theory of psychosis and neuroscience. Front Hum Neurosci 2022; 16:956831. [PMID: 36590059 PMCID: PMC9795812 DOI: 10.3389/fnhum.2022.956831] [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: 05/30/2022] [Accepted: 11/21/2022] [Indexed: 12/15/2022] Open
Abstract
The economic conceptualization of Freudian metapsychology, based on an energetics model of the psyche's workings, offers remarkable commonalities with some recent discoveries in neuroscience, notably in the field of neuroenergetics. The pattern of cerebral activity at resting state and the identification of a default mode network (DMN), a network of areas whose activity is detectable at baseline conditions by neuroimaging techniques, offers a promising field of research in the dialogue between psychoanalysis and neuroscience. In this article we study one significant clinical application of this interdisciplinary dialogue by looking at the role of the DMN in the psychopathology of schizophrenia. Anomalies in the functioning of the DMN have been observed in schizophrenia. Studies have evidenced the existence of hyperactivity in this network in schizophrenia patients, particularly among those for whom a positive symptomatology is dominant. These data are particularly interesting when considered from the perspective of the psychoanalytic understanding of the positive symptoms of psychosis, most notably the Freudian hypothesis of delusions as an "attempt at recovery." Combining the data from research in neuroimaging of schizophrenia patients with the Freudian hypothesis, we propose considering the hyperactivity of the DMN as a consequence of a process of massive reassociation of traces occurring in schizophrenia. This is a process that may constitute an attempt at minimizing the excess of free energy present in psychosis. Modern models of active inference and the free energy principle (FEP) may shed some light on these processes.
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Affiliation(s)
- Jessica Tran The
- INSERM U1077 Neuropsychologie et Imagerie de la Mémoire Humaine, Caen, France,Centre Hospitalier Universitaire de Caen, Caen, France,Université de Caen Normandie, Caen, France,Ecole Pratique des Hautes Etudes, Université Paris Sciences et Lettres, Paris, France,Agalma Foundation Geneva, Geneva, Switzerland,Cyceron, Caen, France,*Correspondence: Jessica Tran The
| | | | - Pierre J. Magistretti
- Agalma Foundation Geneva, Geneva, Switzerland,Division of Biological and Environmental Sciences and Engineering (BESE), King Abdullah University of Science and Technology, Thuwal, Saudi Arabia,Brain Mind Institute, Swiss Federal Institute of Technology Lausanne, Lausanne, Switzerland
| | - Francois Ansermet
- Agalma Foundation Geneva, Geneva, Switzerland,Département de Psychiatrie, Faculté de Médecine, Université de Genève, Geneva, Switzerland
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4
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Min J, Young G, Umar A, Kampfschulte A, Ahrar A, Miller M, Khan N, Wees N, Chalfoun N, Khan M. Neurogenic cardiac outcome in patients after acute ischemic stroke: The brain and heart connection. J Stroke Cerebrovasc Dis 2022; 31:106859. [PMID: 36323165 DOI: 10.1016/j.jstrokecerebrovasdis.2022.106859] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/14/2022] [Accepted: 10/20/2022] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Neurogenic cardiac impairment can occur after acute ischemic stroke (AIS), but the mapping of the neuroanatomic correlation of stroke-related myocardial injury remains uncertain. This study aims to identify the association between cardiac outcomes and middle cerebral artery (MCA) ischemic stroke, with or without insular cortex involvement, as well as the impact of new-onset atrial fibrillation (AF) after AIS on recurrent stroke. METHODS Serial measurements of high sensitivity troponin T (TnT), brain natriuretic peptide (BNP), electrocardiography (ECG), echocardiogram, and cardiac monitoring were performed on 415 patients with imaging confirmed MCA stroke, with or without insular involvement. Patients with renal failure, recent cardiovascular events, or congestive heart failure were excluded. RESULTS One hundred fifteen patients (28%) had left MCA infarcts with insular involvement, 122 (29%) had right MCA infarcts involving insular cortex, and 178 (43%) had no insular involvement. Patients with left MCA stroke with insular involvement tended to exhibit higher BNP and TnI, and transient cardiac dysfunction, which mimicked Takotsubo cardiomyopathy in 10 patients with left ventricular ejection fraction (LVEF) of 20-40%. Incidence of new-onset AF was higher in right MCA stroke involving insula (39%) than left MCA involving insula (4%). Nine out of fifty-three patients with new-onset AF were not on anticoagulant therapy due to various reasons; none of them experienced recurrent AF or stroke during up to a 3-year follow-up period. Statistically significant correlations between BNP or TnT elevation and left insular infarcts, as well as the incidence of AF and right insular infarcts, were revealed using linear regression analysis. CONCLUSIONS The present study demonstrated that acute left MCA stroke with insular involvement could cause transient cardiac dysfunction and elevated cardiac enzymes without persistent negative outcomes in the setting of health baseline cardiac condition. The incidence of new-onset AF was significantly higher in patients with right MCA stroke involving the insula. There was no increased risk of recurrent ischemic stroke in nine patients with newly developed AF who were not on anticoagulant therapy, which indicated a need for further research on presumed neurogenic AF and its management.
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Affiliation(s)
- Jiangyong Min
- Department of Neurosciences and Comprehensive Stroke Center, Spectrum Health and Michigan State University College of Human Medicine, 25 Michigan Street NE, Suite 6100, Grand Rapids, MI 49503, United States.
| | - Grant Young
- Department of Neurology, Vanderbilt University School of Medicine, Nashville, TN, United States
| | - Abdullah Umar
- Stephen M. Ross School of Business, University of Michigan, Ann Arbor, MI, United States
| | - Andrew Kampfschulte
- Offices of Research and Education, Spectrum Health, Grand Rapids, MI, United States
| | - Asad Ahrar
- Department of Neurosciences and Comprehensive Stroke Center, Spectrum Health and Michigan State University College of Human Medicine, 25 Michigan Street NE, Suite 6100, Grand Rapids, MI 49503, United States
| | - Malgorzata Miller
- Department of Neurosciences and Comprehensive Stroke Center, Spectrum Health and Michigan State University College of Human Medicine, 25 Michigan Street NE, Suite 6100, Grand Rapids, MI 49503, United States
| | - Nadeem Khan
- Department of Neurosciences and Comprehensive Stroke Center, Spectrum Health and Michigan State University College of Human Medicine, 25 Michigan Street NE, Suite 6100, Grand Rapids, MI 49503, United States
| | - Nabil Wees
- Department of Neurosciences and Comprehensive Stroke Center, Spectrum Health and Michigan State University College of Human Medicine, 25 Michigan Street NE, Suite 6100, Grand Rapids, MI 49503, United States
| | - Nagib Chalfoun
- Department of Cardiovascular Medicine, Frederik Meijer Heart and Vascular Institute, Spectrum Health and Michigan State University College of Human Medicine, Grand Rapids, MI, United States
| | - Muhib Khan
- Department of Neurosciences and Comprehensive Stroke Center, Spectrum Health and Michigan State University College of Human Medicine, 25 Michigan Street NE, Suite 6100, Grand Rapids, MI 49503, United States
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5
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Sanchez-Rangel E, Deajon-Jackson J, Hwang JJ. Pathophysiology and management of hypoglycemia in diabetes. Ann N Y Acad Sci 2022; 1518:25-46. [PMID: 36202764 DOI: 10.1111/nyas.14904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In the century since the discovery of insulin, diabetes has changed from an early death sentence to a manageable chronic disease. This change in longevity and duration of diabetes coupled with significant advances in therapeutic options for patients has fundamentally changed the landscape of diabetes management, particularly in patients with type 1 diabetes mellitus. However, hypoglycemia remains a major barrier to achieving optimal glycemic control. Current understanding of the mechanisms of hypoglycemia has expanded to include not only counter-regulatory hormonal responses but also direct changes in brain glucose, fuel sensing, and utilization, as well as changes in neural networks that modulate behavior, mood, and cognition. Different strategies to prevent and treat hypoglycemia have been developed, including educational strategies, new insulin formulations, delivery devices, novel technologies, and pharmacologic targets. This review article will discuss current literature contributing to our understanding of the myriad of factors that lead to the development of clinically meaningful hypoglycemia and review established and novel therapies for the prevention and treatment of hypoglycemia.
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Affiliation(s)
- Elizabeth Sanchez-Rangel
- Department of Internal Medicine, Section of Endocrinology, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Jelani Deajon-Jackson
- Department of Internal Medicine, Section of Endocrinology, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Janice Jin Hwang
- Department of Internal Medicine, Section of Endocrinology, Yale University School of Medicine, New Haven, Connecticut, USA.,Division of Endocrinology, Department of Internal Medicine, University of North Carolina - Chapel Hill, Chapel Hill, North Carolina, USA
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6
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Jacob P, Nwokolo M, Cordon SM, Macdonald IA, Zelaya FO, Amiel SA, O'Daly O, Choudhary P. Altered functional connectivity during hypoglycaemia in type 1 diabetes. J Cereb Blood Flow Metab 2022; 42:1451-1462. [PMID: 35209745 PMCID: PMC9274862 DOI: 10.1177/0271678x221082911] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Behavioural responses to hypoglycaemia require coordinated recruitment of broadly distributed networks of interacting brain regions. We investigated hypoglycaemia-related changes in brain connectivity in people without diabetes (ND) and with type 1 diabetes with normal (NAH) or impaired (IAH) hypoglycaemia awareness. Two-step hyperinsulinaemic hypoglycaemic clamps were performed in 14 ND, 15 NAH and 22 IAH participants. BOLD timeseries were acquired at euglycaemia (5.0 mmol/L) and hypoglycaemia (2.6 mmol/L), with symptom and counter-regulatory hormone measurements. We investigated hypoglycaemia-related connectivity changes using established seed regions for the default mode (DMN), salience (SN) and central executive (CEN) networks and regions whose activity is modulated by hypoglycaemia: the thalamus and right inferior frontal gyrus (RIFG). Hypoglycaemia-induced changes in the DMN, SN and CEN were evident in NAH (all p < 0.05), with no changes in ND or IAH. However, in IAH there was a reduction in connectivity between regions within the RIFG (p = 0.001), not evident in the ND or NAH groups. We conclude that hypoglycaemia induces coordinated recruitment of the DMN and SN in diabetes with preserved hypoglycaemia awareness which is absent in IAH and ND. Changes in connectivity in the RIFG, a region associated with attentional modulation, may be key in impaired hypoglycaemia awareness.
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Affiliation(s)
- Peter Jacob
- Diabetes Research Group (Denmark Hill), Faculty of Life Sciences and Medicine, King's College London, London, UK
| | - Munachiso Nwokolo
- Diabetes Research Group (Denmark Hill), Faculty of Life Sciences and Medicine, King's College London, London, UK
| | - Sally M Cordon
- School of Life Sciences, MRC-ARUK Centre of Excellence in Musculoskeletal Ageing, Nottingham University Medical School, Queen's Medical Centre, Nottingham, UK
| | - Ian A Macdonald
- School of Life Sciences, MRC-ARUK Centre of Excellence in Musculoskeletal Ageing, Nottingham University Medical School, Queen's Medical Centre, Nottingham, UK
| | - Fernando O Zelaya
- Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Stephanie A Amiel
- Diabetes Research Group (Denmark Hill), Faculty of Life Sciences and Medicine, King's College London, London, UK
| | - Owen O'Daly
- Centre for Neuroimaging Sciences, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Pratik Choudhary
- Diabetes Research Group (Denmark Hill), Faculty of Life Sciences and Medicine, King's College London, London, UK
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7
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van Meijel LA, van Asten JJA, Grandjean J, Heerschap A, Tack CJ, van der Graaf M, Wiegers EC, de Galan BE. Effect of lactate administration on cerebral blood flow during hypoglycemia in people with type 1 diabetes. BMJ Open Diabetes Res Care 2022; 10:10/2/e002401. [PMID: 35321886 PMCID: PMC8943734 DOI: 10.1136/bmjdrc-2021-002401] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Accepted: 02/22/2022] [Indexed: 11/11/2022] Open
Abstract
INTRODUCTION Impaired awareness of hypoglycemia, clinically reflected by the inability to timely detect hypoglycemia, affects approximately 25% of the people with type 1 diabetes. Both altered brain lactate handling and increased cerebral blood flow (CBF) during hypoglycemia appear to be involved in the pathogenesis of impaired awareness of hypoglycemia. Here we examine the effect of lactate on CBF during hypoglycemia. RESEARCH DESIGN AND METHODS Nine people with type 1 diabetes and normal awareness of hypoglycemia underwent two hyperinsulinemic euglycemic-hypoglycemic (3.0 mmol/L) glucose clamps in a 3T MR system, once with sodium lactate infusion and once with sodium chloride infusion. Global and regional changes in CBF were determined using pseudocontinuous arterial spin labeling. RESULTS Lactate (3.3±0.6 vs 0.9±0.2 mmol/L during lactate infusion vs placebo infusion, respectively) suppressed the counter-regulatory hormone responses to hypoglycemia. Global CBF increased considerably in response to intravenous lactate infusion but did not further increase during hypoglycemia. Lactate also blunted the hypoglycemia-induced regional redistribution of CBF towards the thalamus. CONCLUSIONS Elevated lactate levels enhance global CBF and blunt the thalamic CBF response during hypoglycemia in patients with type 1 diabetes, mimicking observations of impaired awareness of hypoglycemia. These findings suggest that alteration of CBF associated with lactate may play a role in some aspects of the development of impaired awareness of hypoglycemia. TRIAL REGISTRATION NUMBER NCT03730909.
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Affiliation(s)
- Lian A van Meijel
- Department of Internal Medicine, Radboudumc, Nijmegen, The Netherlands
- Department of Internal Medicine, Maxima Medical Centre, Veldhoven, The Netherlands
| | - Jack J A van Asten
- Department of Medical Imaging/Radiology, Radboudumc, Nijmegen, The Netherlands
| | - Joanes Grandjean
- Department of Medical Imaging/Radiology, Radboudumc, Nijmegen, The Netherlands
- Department of Cognitive Neuroscience, Donders Institute for Brain, Cognition and Behaviour, Centre for Neuroscience, Radboudumc, Nijmegen, The Netherlands
| | - Arend Heerschap
- Department of Medical Imaging/Radiology, Radboudumc, Nijmegen, The Netherlands
| | - Cornelis J Tack
- Department of Internal Medicine, Radboudumc, Nijmegen, The Netherlands
| | - Marinette van der Graaf
- Department of Medical Imaging/Radiology, Radboudumc, Nijmegen, The Netherlands
- Department of Pediatrics, Radboudumc, Nijmegen, The Netherlands
| | - Evita C Wiegers
- Department of Medical Imaging/Radiology, Radboudumc, Nijmegen, The Netherlands
- High Field MR Research Group, Department of Radiology, University Medical Center Utrecht Imaging Division, Utrecht, The Netherlands
| | - Bastiaan E de Galan
- Department of Internal Medicine, Radboudumc, Nijmegen, The Netherlands
- Department of Internal Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands
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8
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Powers WJ, An H, Diringer MN. Cerebral Blood Flow and Metabolism. Stroke 2022. [DOI: 10.1016/b978-0-323-69424-7.00003-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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9
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Zamani A, Carhart-Harris R, Christoff K. Prefrontal contributions to the stability and variability of thought and conscious experience. Neuropsychopharmacology 2022; 47:329-348. [PMID: 34545195 PMCID: PMC8616944 DOI: 10.1038/s41386-021-01147-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 08/02/2021] [Accepted: 08/03/2021] [Indexed: 02/08/2023]
Abstract
The human prefrontal cortex is a structurally and functionally heterogenous brain region, including multiple subregions that have been linked to different large-scale brain networks. It contributes to a broad range of mental phenomena, from goal-directed thought and executive functions to mind-wandering and psychedelic experience. Here we review what is known about the functions of different prefrontal subregions and their affiliations with large-scale brain networks to examine how they may differentially contribute to the diversity of mental phenomena associated with prefrontal function. An important dimension that distinguishes across different kinds of conscious experience is the stability or variability of mental states across time. This dimension is a central feature of two recently introduced theoretical frameworks-the dynamic framework of thought (DFT) and the relaxed beliefs under psychedelics (REBUS) model-that treat neurocognitive dynamics as central to understanding and distinguishing between different mental phenomena. Here, we bring these two frameworks together to provide a synthesis of how prefrontal subregions may differentially contribute to the stability and variability of thought and conscious experience. We close by considering future directions for this work.
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Affiliation(s)
- Andre Zamani
- Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver, BC, Canada.
| | - Robin Carhart-Harris
- Centre for Psychedelic Research, Department of Brain Sciences, Imperial College London, London, UK
| | - Kalina Christoff
- Department of Psychology, University of British Columbia, 2136 West Mall, Vancouver, BC, Canada
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10
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Schouwenaars IT, de Dreu MJ, Rutten GJM, Ramsey NF, Jansma JM. A functional MRI study of presurgical cognitive deficits in glioma patients. Neurooncol Pract 2021; 8:81-90. [PMID: 33659067 PMCID: PMC7906265 DOI: 10.1093/nop/npaa059] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Background The main goal of this functional MRI (fMRI) study was to examine whether cognitive deficits in glioma patients prior to treatment are associated with abnormal brain activity in either the central executive network (CEN) or default mode network (DMN). Methods Forty-six glioma patients, and 23 group-matched healthy controls (HCs) participated in this fMRI experiment, performing an N-back task. Additionally, cognitive profiles of patients were evaluated outside the scanner. A region of interest–based analysis was used to compare brain activity in CEN and DMN between groups. Post hoc analyses were performed to evaluate differences between low-grade glioma (LGG) and high-grade glioma (HGG) patients. Results In-scanner performance was lower in glioma patients compared to HCs. Neuropsychological testing indicated cognitive impairment in LGG as well as HGG patients. fMRI results revealed normal CEN activation in glioma patients, whereas patients showed reduced DMN deactivation compared to HCs. Brain activity levels did not differ between LGG and HGG patients. Conclusions Our study suggests that cognitive deficits in glioma patients prior to treatment are associated with reduced responsiveness of the DMN, but not with abnormal CEN activation. These results suggest that cognitive deficits in glioma patients reflect a reduced capacity to achieve a brain state necessary for normal cognitive performance, rather than abnormal functioning of executive brain regions. Solely focusing on increases in brain activity may well be insufficient if we want to understand the underlying brain mechanism of cognitive impairments in patients, as our results indicate the importance of assessing deactivation.
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Affiliation(s)
- Irena T Schouwenaars
- Department of Neurosurgery, Elisabeth-TweeSteden Hospital, Tilburg, the Netherlands.,Department of Neurology and Neurosurgery, UMC Utrecht Brain Center, Utrecht University, Utrecht, the Netherlands
| | - Miek J de Dreu
- Department of Neurosurgery, Elisabeth-TweeSteden Hospital, Tilburg, the Netherlands.,Department of Neurology and Neurosurgery, UMC Utrecht Brain Center, Utrecht University, Utrecht, the Netherlands
| | - Geert-Jan M Rutten
- Department of Neurosurgery, Elisabeth-TweeSteden Hospital, Tilburg, the Netherlands
| | - Nick F Ramsey
- Department of Neurology and Neurosurgery, UMC Utrecht Brain Center, Utrecht University, Utrecht, the Netherlands
| | - Johan M Jansma
- Department of Neurosurgery, Elisabeth-TweeSteden Hospital, Tilburg, the Netherlands.,Department of Neurology and Neurosurgery, UMC Utrecht Brain Center, Utrecht University, Utrecht, the Netherlands
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11
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Nwokolo M, Amiel SA, O'Daly O, Macdonald IA, Zelaya FO, Choudhary P. Restoration of Hypoglycemia Awareness Alters Brain Activity in Type 1 Diabetes. Diabetes Care 2021; 44:533-540. [PMID: 33328282 DOI: 10.2337/dc20-1250] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 11/12/2020] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Impaired awareness of hypoglycemia (IAH) in type 1 diabetes (T1D) is a major risk factor for severe hypoglycemia (SH) and is associated with atypical responses to hypoglycemia in brain regions involved in arousal, decision making, and memory. Whether restoration of hypoglycemia awareness alters these responses is unknown. We sought to investigate the impact of awareness restoration on brain responses to hypoglycemia. RESEARCH DESIGN AND METHODS Twelve adults with T1D and IAH underwent pseudocontinuous arterial spin labeling functional MRI during a hypoglycemic clamp (5-2.6 mmol/L) before and after a hypoglycemia avoidance program of structured education (Dose Adjustment for Normal Eating), specialist support, and sensor-augmented pump therapy (Medtronic MiniMed 640G). Hypoglycemic cerebral blood flow (CBF) responses were compared pre- and postintervention using predefined region-of-interest analysis of the thalamus, anterior cingulate cortex (ACC), orbitofrontal cortex (OFC), and hippocampus. RESULTS Postintervention, Gold and Clarke scores fell (6.0 ± 1.0 to 4.0 ± 1.6, P = 0.0002, and 5.7 ± 1.7 to 3.4 ± 1.8, P = 0.0008, respectively), SH rates reduced (1.5 ± 2 to 0.3 ± 0.5 episodes per year, P = 0.03), hypoglycemic symptom scores increased (18.8 ± 6.3 to 27.3 ± 12.7, P = 0.02), and epinephrine responses did not change (P = 0.2). Postintervention, hypoglycemia induced greater increases in ACC CBF (P = 0.01, peak voxel coordinates [6, 40, -2]), while thalamic and OFC activity did not change. CONCLUSIONS Increased blood flow is seen within brain pathways involved in internal self-awareness and decision making (ACC) after restoration of hypoglycemia awareness, suggesting partial recovery of brain responses lost in IAH. Resistance of frontothalamic networks, involved in arousal and emotion processing, may explain why not all individuals with IAH achieve awareness restoration with education and technology alone.
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Affiliation(s)
- Munachiso Nwokolo
- Department of Diabetes, School of Life Course Sciences, King's College London, London, U.K. .,King's College Hospital NHS Foundation Trust, London, U.K
| | - Stephanie A Amiel
- Department of Diabetes, School of Life Course Sciences, King's College London, London, U.K.,King's College Hospital NHS Foundation Trust, London, U.K
| | - Owen O'Daly
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, U.K
| | - Ian A Macdonald
- School of Life Sciences, MRC-Arthritis Research UK Centre of Excellence in Musculoskeletal Ageing, Nottingham University Medical School, Queen's Medical Centre, Nottingham, U.K
| | - Fernando O Zelaya
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, U.K
| | - Pratik Choudhary
- Department of Diabetes, School of Life Course Sciences, King's College London, London, U.K.,King's College Hospital NHS Foundation Trust, London, U.K
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12
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Nwokolo M, Amiel SA, O'Daly O, Byrne ML, Wilson BM, Pernet A, Cordon SM, Macdonald IA, Zelaya FO, Choudhary P. Hypoglycemic thalamic activation in type 1 diabetes is associated with preserved symptoms despite reduced epinephrine. J Cereb Blood Flow Metab 2020; 40:787-798. [PMID: 31006309 PMCID: PMC7168783 DOI: 10.1177/0271678x19842680] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Brain responses to low plasma glucose may be key to understanding the behaviors that prevent severe hypoglycemia in type 1 diabetes. This study investigated the impact of long duration, hypoglycemia aware type 1 diabetes on cerebral blood flow responses to hypoglycemia. Three-dimensional pseudo-continuous arterial spin labeling magnetic resonance imaging was performed in 15 individuals with type 1 diabetes and 15 non-diabetic controls during a two-step hyperinsulinemic glucose clamp. Symptom, hormone, global cerebral blood flow and regional cerebral blood flow responses to hypoglycemia were measured. Epinephrine release during hypoglycemia was attenuated in type 1 diabetes, but symptom score rose comparably in both groups. A rise in global cerebral blood flow did not differ between groups. Regional cerebral blood flow increased in the thalamus and fell in the hippocampus and temporal cortex in both groups. Type 1 diabetes demonstrated lesser anterior cingulate cortex activation; however, this difference did not survive correction for multiple comparisons. Thalamic cerebral blood flow change correlated with autonomic symptoms, and anterior cingulate cortex cerebral blood flow change correlated with epinephrine response across groups. The thalamus may thus be involved in symptom responses to hypoglycemia, independent of epinephrine action, while anterior cingulate cortex activation may be linked to counterregulation. Activation of these regions may have a role in hypoglycemia awareness and avoidance of problematic hypoglycemia.
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Affiliation(s)
- Munachiso Nwokolo
- Department of Diabetes, School of Life Course Sciences, King's College London, London, UK.,King's College Hospital, NHS Foundation Trust, London, UK
| | - Stephanie A Amiel
- Department of Diabetes, School of Life Course Sciences, King's College London, London, UK.,King's College Hospital, NHS Foundation Trust, London, UK
| | - Owen O'Daly
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Megan L Byrne
- Department of Diabetes, School of Life Course Sciences, King's College London, London, UK
| | - Bula M Wilson
- Department of Diabetes, School of Life Course Sciences, King's College London, London, UK
| | - Andrew Pernet
- Department of Diabetes, School of Life Course Sciences, King's College London, London, UK
| | - Sally M Cordon
- School of Life Sciences, MRC-ARUK Centre of Excellence in Musculoskeletal Ageing, Nottingham University Medical School, Queen's Medical Centre, Nottingham, UK
| | - Ian A Macdonald
- School of Life Sciences, MRC-ARUK Centre of Excellence in Musculoskeletal Ageing, Nottingham University Medical School, Queen's Medical Centre, Nottingham, UK
| | - Fernando O Zelaya
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Pratik Choudhary
- Department of Diabetes, School of Life Course Sciences, King's College London, London, UK.,King's College Hospital, NHS Foundation Trust, London, UK
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13
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Nwokolo M, Amiel SA, O'Daly O, Byrne ML, Wilson BM, Pernet A, Cordon SM, Macdonald IA, Zelaya FO, Choudhary P. Impaired Awareness of Hypoglycemia Disrupts Blood Flow to Brain Regions Involved in Arousal and Decision Making in Type 1 Diabetes. Diabetes Care 2019; 42:2127-2135. [PMID: 31455689 DOI: 10.2337/dc19-0337] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 08/07/2019] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Impaired awareness of hypoglycemia (IAH) affects one-quarter of adults with type 1 diabetes and significantly increases the risk of severe hypoglycemia. Differences in regional brain responses to hypoglycemia may contribute to the susceptibility of this group to problematic hypoglycemia. This study investigated brain responses to hypoglycemia in hypoglycemia aware (HA) and IAH adults with type 1 diabetes, using three-dimensional pseudo-continuous arterial spin labeling (3D pCASL) functional MRI to measure changes in regional cerebral blood flow (CBF). RESEARCH DESIGN AND METHODS Fifteen HA and 19 IAH individuals underwent 3D pCASL functional MRI during a two-step hyperinsulinemic glucose clamp. Symptom, hormone, global, and regional CBF responses to hypoglycemia (47 mg/dL [2.6 mmol/L]) were measured. RESULTS In response to hypoglycemia, total symptom score did not change in those with IAH (P = 0.25) but rose in HA participants (P < 0.001). Epinephrine, cortisol, and growth hormone responses to hypoglycemia were lower in the IAH group (P < 0.05). Hypoglycemia induced a rise in global CBF (HA P = 0.01, IAH P = 0.04) but was not different between groups (P = 0.99). IAH participants showed reduced regional CBF responses within the thalamus (P = 0.002), right lateral orbitofrontal cortex (OFC) (P = 0.002), and right dorsolateral prefrontal cortex (P = 0.036) and a lesser decrease of CBF in the left hippocampus (P = 0.023) compared with the HA group. Thalamic and right lateral OFC differences survived Bonferroni correction. CONCLUSIONS Responses to hypoglycemia of brain regions involved in arousal, decision making, and reward are altered in IAH. Changes in these pathways may disrupt IAH individuals' ability to recognize hypoglycemia, impairing their capacity to manage hypoglycemia effectively and benefit fully from conventional therapeutic pathways to restore awareness.
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Affiliation(s)
- Munachiso Nwokolo
- Department of Diabetes, School of Life Course Sciences, King's College London, London, U.K. .,King's College Hospital NHS Foundation Trust, London, U.K
| | - Stephanie A Amiel
- Department of Diabetes, School of Life Course Sciences, King's College London, London, U.K.,King's College Hospital NHS Foundation Trust, London, U.K
| | - Owen O'Daly
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, U.K
| | - Megan L Byrne
- Department of Diabetes, School of Life Course Sciences, King's College London, London, U.K
| | - Bula M Wilson
- Department of Diabetes, School of Life Course Sciences, King's College London, London, U.K
| | - Andrew Pernet
- Department of Diabetes, School of Life Course Sciences, King's College London, London, U.K
| | - Sally M Cordon
- School of Life Sciences, MRC Arthritis Research UK Centre of Excellence in Musculoskeletal Ageing, University of Nottingham Medical School, Queen's Medical Centre, Nottingham, U.K
| | - Ian A Macdonald
- School of Life Sciences, MRC Arthritis Research UK Centre of Excellence in Musculoskeletal Ageing, University of Nottingham Medical School, Queen's Medical Centre, Nottingham, U.K
| | - Fernando O Zelaya
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, U.K
| | - Pratik Choudhary
- Department of Diabetes, School of Life Course Sciences, King's College London, London, U.K.,King's College Hospital NHS Foundation Trust, London, U.K
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14
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Lei H, Preitner F, Labouèbe G, Gruetter R, Thorens B. Glucose transporter 2 mediates the hypoglycemia-induced increase in cerebral blood flow. J Cereb Blood Flow Metab 2019; 39:1725-1736. [PMID: 29561214 PMCID: PMC6727137 DOI: 10.1177/0271678x18766743] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Glucose transporter 2 (Glut2)-positive cells are sparsely distributed in brain and play an important role in the stimulation of glucagon secretion in response to hypoglycemia. We aimed to determine if Glut2-positive cells can influence another response to hypoglycemia, i.e. increased cerebral blood flow (CBF). CBF of adult male mice devoid of Glut2, either globally (ripglut1:glut2-/-) or in the nervous system only (NG2KO), and their respective controls were studied under basal glycemia and insulin-induced hypoglycemia using quantitative perfusion magnetic resonance imaging at 9.4 T. The effect on CBF of optogenetic activation of hypoglycemia responsive Glut2-positive neurons of the paraventricular thalamic area was measured in mice expressing channelrhodopsin2 under the control of the Glut2 promoter. We found that in both ripglut1:glut2-/- mice and NG2KO mice, CBF in basal conditions was higher than in their respective controls and not further activated by hypoglycemia, as measured in the hippocampus, hypothalamus and whole brain. Conversely, optogenetic activation of Glut2-positive cells in the paraventricular thalamic nucleus induced a local increase in CBF similar to that induced by hypoglycemia. Thus, Glut2 expression in the nervous system is required for the control of CBF in response to changes in blood glucose concentrations.
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Affiliation(s)
- Hongxia Lei
- 1 AIT, Center for Biomedical Imaging (CIBM-AIT), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.,2 Department of Radiology, University of Geneva, Geneva, Switzerland
| | - Frédéric Preitner
- 3 Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland.,4 Mouse Metabolic Evaluation Facility, Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Gwenaël Labouèbe
- 3 Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Rolf Gruetter
- 1 AIT, Center for Biomedical Imaging (CIBM-AIT), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.,2 Department of Radiology, University of Geneva, Geneva, Switzerland.,5 Department of Radiology, University of Lausanne, Lausanne, Switzerland
| | - Bernard Thorens
- 3 Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
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15
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Saleem Mir M, Maqbool Darzi M, Musadiq Khan H, Ahmad Kamil S, Hassan Sofi A, Ahmad Wani S. Pathomorphological effects of Alloxan induced acute hypoglycaemia in rabbits. ALEXANDRIA JOURNAL OF MEDICINE 2019. [DOI: 10.1016/j.ajme.2013.03.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
- Masood Saleem Mir
- Division of Veterinary Pathology, F.V.Sc. & A.H. , Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir , Shuhama, Alusteng , Kashmir (J&K), 190 006, India
| | - Mohammad Maqbool Darzi
- Division of Veterinary Pathology, F.V.Sc. & A.H. , Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir , Shuhama, Alusteng , Kashmir (J&K), 190 006, India
| | - Hilal Musadiq Khan
- MRCSG, F.V.Sc. & A.H, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir , Shuhama, Alusteng , Kashmir (J&K), 190 006, India
| | - Shayaib Ahmad Kamil
- Division of Veterinary Pathology, F.V.Sc. & A.H. , Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir , Shuhama, Alusteng , Kashmir (J&K), 190 006, India
| | - Asif Hassan Sofi
- Division of LPT, F.V.Sc. & A.H , Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir , Shuhama, Alusteng , Kashmir (J&K), 190 006, India
| | - Sarfraz Ahmad Wani
- Division of LPT, F.V.Sc. & A.H , Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir , Shuhama, Alusteng , Kashmir (J&K), 190 006, India
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16
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Orfanos S, Toygar T, Berthold-Losleben M, Chechko N, Durst A, Laoutidis ZG, Vocke S, Weidenfeld C, Schneider F, Karges W, Beckmann CF, Habel U, Kohn N. Investigating the impact of overnight fasting on intrinsic functional connectivity: a double-blind fMRI study. Brain Imaging Behav 2019; 12:1150-1159. [PMID: 29071464 PMCID: PMC6063348 DOI: 10.1007/s11682-017-9777-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The human brain depends mainly on glucose supply from circulating blood as an energy substrate for its metabolism. Most of the energy produced by glucose catabolism in the brain is used to support intrinsic communication purposes in the absence of goal-directed activity. This intrinsic brain function can be detected with fMRI as synchronized fluctuations of the BOLD signal forming functional networks. Here, we report results from a double-blind, placebo controlled, cross-over study addressing changes in intrinsic brain activity in the context of very low, yet physiological, blood glucose levels after overnight fasting. Comparison of four major resting state networks in a fasting state and a state of elevated blood glucose levels after glucagon infusion revealed altered patterns of functional connectivity only in a small region of the posterior default mode network, while the rest of the networks appeared unaffected. Furthermore, low blood glucose was associated with changes in the right frontoparietal network after cognitive effort. Our results suggest that fasting has only limited impact on intrinsic brain activity, while a detrimental impact on a network related to attention is only observable following cognitive effort, which is in line with ego depletion and its reliance on glucose.
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Affiliation(s)
- Stelios Orfanos
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Aachen, Germany. .,Jülich Aachen Research Alliance (JARA) - BRAIN Institute Brain Structure-Function Relationships: Decoding the Human Brain at systemic levels, Forschungszentrum Jülich GmbH and RWTH Aachen University, Jülich, Germany.
| | - Timur Toygar
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Aachen, Germany.,Department of Biology, RWTH Aachen University, 52074, Aachen, Germany
| | - Mark Berthold-Losleben
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Aachen, Germany.,Jülich Aachen Research Alliance (JARA) - BRAIN Institute Brain Structure-Function Relationships: Decoding the Human Brain at systemic levels, Forschungszentrum Jülich GmbH and RWTH Aachen University, Jülich, Germany
| | - Natalya Chechko
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Aachen, Germany.,Jülich Aachen Research Alliance (JARA) - BRAIN Institute Brain Structure-Function Relationships: Decoding the Human Brain at systemic levels, Forschungszentrum Jülich GmbH and RWTH Aachen University, Jülich, Germany
| | - Annette Durst
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Aachen, Germany.,Jülich Aachen Research Alliance (JARA) - BRAIN Institute Brain Structure-Function Relationships: Decoding the Human Brain at systemic levels, Forschungszentrum Jülich GmbH and RWTH Aachen University, Jülich, Germany
| | - Zacharias G Laoutidis
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Aachen, Germany.,Department of Psychiatry and Psychotherapy, University of Düsseldorf, Bergische Landstrasse 2, 40629, Düsseldorf, Germany
| | - Sebastian Vocke
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Aachen, Germany.,Jülich Aachen Research Alliance (JARA) - BRAIN Institute Brain Structure-Function Relationships: Decoding the Human Brain at systemic levels, Forschungszentrum Jülich GmbH and RWTH Aachen University, Jülich, Germany
| | - Caren Weidenfeld
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Aachen, Germany.,Jülich Aachen Research Alliance (JARA) - BRAIN Institute Brain Structure-Function Relationships: Decoding the Human Brain at systemic levels, Forschungszentrum Jülich GmbH and RWTH Aachen University, Jülich, Germany
| | - Frank Schneider
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Aachen, Germany.,Jülich Aachen Research Alliance (JARA) - BRAIN Institute Brain Structure-Function Relationships: Decoding the Human Brain at systemic levels, Forschungszentrum Jülich GmbH and RWTH Aachen University, Jülich, Germany
| | - Wolfram Karges
- Division of Endocrinology and Diabetes, Medical Faculty, RWTH Aachen University, 52074, Aachen, Germany
| | - Christian F Beckmann
- Department of Cognitive Neuroscience, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands.,Centre for Functional MRI of the Brain (FMRIB), University of Oxford, Oxford, UK
| | - Ute Habel
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Aachen, Germany.,Jülich Aachen Research Alliance (JARA) - BRAIN Institute Brain Structure-Function Relationships: Decoding the Human Brain at systemic levels, Forschungszentrum Jülich GmbH and RWTH Aachen University, Jülich, Germany
| | - Nils Kohn
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, RWTH Aachen University, Aachen, Germany.,Department of Cognitive Neuroscience, Radboud University Medical Center, Donders Institute for Brain, Cognition and Behaviour, Nijmegen, The Netherlands
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17
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Embury CM, Wiesman AI, McDermott TJ, Proskovec AL, Heinrichs-Graham E, Lord GH, Brau KL, Drincic AT, Desouza CV, Wilson TW. The impact of type 1 diabetes on neural activity serving attention. Hum Brain Mapp 2018; 40:1093-1100. [PMID: 30368968 DOI: 10.1002/hbm.24431] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 09/24/2018] [Accepted: 10/08/2018] [Indexed: 01/19/2023] Open
Abstract
Type 1 diabetes has been associated with alterations in attentional processing and other cognitive functions, and previous studies have found alterations in both brain structure and function in affected patients. However, these previous neuroimaging studies have generally examined older patients, particularly those with major comorbidities known to affect functioning independent of diabetes. The primary aim of the current study was to examine the neural dynamics of selective attention processing in a young group of patients with type 1 diabetes who were otherwise healthy (i.e., without major comorbidities). Our hypothesis was that these patients would exhibit significant aberrations in attention circuitry relative to closely matched controls. The final sample included 69 participants age 19-35 years old, 35 with type 1 diabetes and 34 matched nondiabetic controls, who completed an Eriksen flanker task while undergoing magnetoencephalography. Significant group differences in flanker interference activity were found across a network of brain regions, including the anterior cingulate, inferior parietal cortices, paracentral lobule, and the left precentral gyrus. In addition, neural activity in the anterior cingulate and the paracentral lobule was correlated with disease duration in patients with type 1 diabetes. These findings suggest that alterations in the neural circuitry underlying selective attention emerge early in the disease process and are specifically related to type 1 diabetes and not common comorbidities. These findings highlight the need for longitudinal studies in large cohorts to clarify the clinical implications of type 1 diabetes on cognition and the brain.
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Affiliation(s)
- Christine M Embury
- Department of Neurological Sciences, University of Nebraska Medical Center (UNMC), Omaha, Nebraska.,Center for Magnetoencephalography, UNMC, Omaha, Nebraska.,Department of Psychology, University of Nebraska Omaha, Omaha, Nebraska
| | - Alex I Wiesman
- Department of Neurological Sciences, University of Nebraska Medical Center (UNMC), Omaha, Nebraska.,Center for Magnetoencephalography, UNMC, Omaha, Nebraska
| | - Timothy J McDermott
- Department of Neurological Sciences, University of Nebraska Medical Center (UNMC), Omaha, Nebraska.,Center for Magnetoencephalography, UNMC, Omaha, Nebraska
| | - Amy L Proskovec
- Department of Neurological Sciences, University of Nebraska Medical Center (UNMC), Omaha, Nebraska.,Center for Magnetoencephalography, UNMC, Omaha, Nebraska.,Department of Psychology, University of Nebraska Omaha, Omaha, Nebraska
| | - Elizabeth Heinrichs-Graham
- Department of Neurological Sciences, University of Nebraska Medical Center (UNMC), Omaha, Nebraska.,Center for Magnetoencephalography, UNMC, Omaha, Nebraska
| | - Grace H Lord
- Department of Internal Medicine, Division of Diabetes, Endocrinology, and Metabolism, UNMC, Omaha, Nebraska
| | - Kaitlin L Brau
- Department of Internal Medicine, Division of Diabetes, Endocrinology, and Metabolism, UNMC, Omaha, Nebraska
| | - Andjela T Drincic
- Department of Internal Medicine, Division of Diabetes, Endocrinology, and Metabolism, UNMC, Omaha, Nebraska
| | - Cyrus V Desouza
- Department of Internal Medicine, Division of Diabetes, Endocrinology, and Metabolism, UNMC, Omaha, Nebraska
| | - Tony W Wilson
- Department of Neurological Sciences, University of Nebraska Medical Center (UNMC), Omaha, Nebraska.,Center for Magnetoencephalography, UNMC, Omaha, Nebraska
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18
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Dunn JT, Choudhary P, Teh MM, Macdonald I, Hunt KF, Marsden PK, Amiel SA. The impact of hypoglycaemia awareness status on regional brain responses to acute hypoglycaemia in men with type 1 diabetes. Diabetologia 2018; 61:1676-1687. [PMID: 29754288 PMCID: PMC6445483 DOI: 10.1007/s00125-018-4622-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 03/05/2018] [Indexed: 12/14/2022]
Abstract
AIMS/HYPOTHESIS Impaired awareness of hypoglycaemia (IAH) in type 1 diabetes increases the risk of severe hypoglycaemia sixfold and can be resistant to intervention. We explored the impact of IAH on central responses to hypoglycaemia to investigate the mechanisms underlying barriers to therapeutic intervention. METHODS We conducted [15O]water positron emission tomography studies of regional brain perfusion during euglycaemia (target 5 mmol/l), hypoglycaemia (achieved level, 2.4 mmol/l) and recovery (target 5 mmol/l) in 17 men with type 1 diabetes: eight with IAH, and nine with intact hypoglycaemia awareness (HA). RESULTS Hypoglycaemia with HA was associated with increased activation in brain regions including the thalamus, insula, globus pallidus (GP), anterior cingulate cortex (ACC), orbital cortex, dorsolateral frontal (DLF) cortex, angular gyrus and amygdala; deactivation occurred in the temporal and parahippocampal regions. IAH was associated with reduced catecholamine and symptom responses to hypoglycaemia vs HA (incremental AUC: autonomic scores, 26.2 ± 35.5 vs 422.7 ± 237.1; neuroglycopenic scores, 34.8 ± 88.8 vs 478.9 ± 311.1; both p < 0.002). There were subtle differences (p < 0.005, k ≥ 50 voxels) in brain activation at hypoglycaemia, including early differences in the right central operculum, bilateral medial orbital (MO) cortex, and left posterior DLF cortex, with additional differences in the ACC, right GP and post- and pre-central gyri in established hypoglycaemia, and lack of deactivation in temporal regions in established hypoglycaemia. CONCLUSIONS/INTERPRETATION Differences in activation in the post- and pre-central gyri may be expected in people with reduced subjective responses to hypoglycaemia. Alterations in the activity of regions involved in the drive to eat (operculum), emotional salience (MO cortex), aversion (GP) and recall (temporal) suggest differences in the perceived importance and urgency of responses to hypoglycaemia in IAH compared with HA, which may be key to the persistence of the condition.
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Affiliation(s)
- Joel T Dunn
- Division of Imaging Sciences and Biomedical Engineering, King's College London, London, UK
| | - Pratik Choudhary
- Diabetes Research Group, King's College London, King's College Hospital Campus, Weston Education Centre, 10 Cutcombe Road, London, SE5 9RJ, UK
- Institute of Diabetes and Obesity, King's Health Partners, London, UK
| | - Ming Ming Teh
- Diabetes Research Group, King's College London, King's College Hospital Campus, Weston Education Centre, 10 Cutcombe Road, London, SE5 9RJ, UK
- Singapore General Hospital, Singapore, Republic of Singapore
| | - Ian Macdonald
- School of Life Sciences, University of Nottingham, Nottingham, UK
| | - Katharine F Hunt
- Diabetes Research Group, King's College London, King's College Hospital Campus, Weston Education Centre, 10 Cutcombe Road, London, SE5 9RJ, UK
- Institute of Diabetes and Obesity, King's Health Partners, London, UK
| | - Paul K Marsden
- Division of Imaging Sciences and Biomedical Engineering, King's College London, London, UK
| | - Stephanie A Amiel
- Diabetes Research Group, King's College London, King's College Hospital Campus, Weston Education Centre, 10 Cutcombe Road, London, SE5 9RJ, UK.
- Institute of Diabetes and Obesity, King's Health Partners, London, UK.
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19
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Calancie OG, Khalid-Khan S, Booij L, Munoz DP. Eye movement desensitization and reprocessing as a treatment for PTSD: current neurobiological theories and a new hypothesis. Ann N Y Acad Sci 2018; 1426:127-145. [PMID: 29931688 DOI: 10.1111/nyas.13882] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 04/16/2018] [Accepted: 05/24/2018] [Indexed: 12/25/2022]
Abstract
Eye movement desensitization and reprocessing (EMDR), a form of psychotherapy for individuals with post-traumatic stress disorder (PTSD), has long been a controversial topic, hampered in part by a lack of understanding of the neural mechanisms that contribute to its remedial effect. Here, we review current theories describing EMDR's potential neurobiological mechanisms of action involving working memory, interhemispheric communication, de-arousal, and memory reconsolidation. We then discuss recent studies describing the temporal and spatial aspects of smooth pursuit and predictive saccades, which resemble those made during EMDR, and their neural correlates within the default mode network (DMN) and cerebellum. We hypothesize that if the production of bilateral predictive eye movements is supportive of DMN and cerebellum activation, then therapies that shift the brain towards this state correspondingly would benefit the processes regulated by these structures (i.e., memory retrieval, relaxation, and associative learning), all of which are essential components for PTSD recovery. We propose that the timing of sensory stimulation may be relevant to treatment effect and could be adapted across different patients depending on their baseline saccade metrics. Empirical data in support of this model are reviewed and experimental predictions are discussed.
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Affiliation(s)
- Olivia G Calancie
- Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada
- Division of Child and Youth Mental Health, Kingston Health Sciences Centre, Kingston, Ontario, Canada
| | - Sarosh Khalid-Khan
- Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada
- Division of Child and Youth Mental Health, Kingston Health Sciences Centre, Kingston, Ontario, Canada
| | - Linda Booij
- Department of Psychology, Concordia University, Montréal, Quebec, Canada
- Department of Psychology, Queen's University, Kingston, Ontario, Canada
| | - Douglas P Munoz
- Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
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20
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Qiu L, Xia M, Cheng B, Yuan L, Kuang W, Bi F, Ai H, Gu Z, Lui S, Huang X, He Y, Gong Q. Abnormal dynamic functional connectivity of amygdalar subregions in untreated patients with first-episode major depressive disorder. J Psychiatry Neurosci 2018; 43:170112. [PMID: 29634476 PMCID: PMC6019355 DOI: 10.1503/jpn.170112] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 09/20/2017] [Accepted: 11/17/2017] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Accumulating evidence supports the concept of the amygdala as a complex of structurally and functionally heterogeneous nuclei rather than as a single homogeneous structure. However, changes in resting-state functional connectivity in amygdalar subregions have not been investigated in major depressive disorder (MDD). Here, we explored whether amygdalar subregions - including the laterobasal, centromedial (CM) and superficial (SF) areas - exhibited distinct disruption patterns for different dynamic functional connectivity (dFC) properties, and whether these different properties were correlated with clinical information in patients with MDD. METHODS Thirty untreated patients with first-episode MDD and 62 matched controls were included. We assessed between-group differences in the mean strength of dFC in each amygdalar subregion in the whole brain using general linear model analysis. RESULTS The patients with MDD showed decreased strength in positive dFC between the left CM/SF and brainstem and between the left SF and left thalamus; they showed decreased strength in negative dFC between the left CM and right superior frontal gyrus (p < 0.05, family-wise error-corrected). We found significant positive correlations between age at onset and the mean positive strength of dFC in the left CM/brainstem in patients with MDD. LIMITATIONS The definitions of amygdalar subregions were based on a cytoarchitectonic delineation, and the temporal resolution of the fMRI was slow (repetition time = 2 s). CONCLUSION These findings confirm the distinct dynamic functional pathway of amygdalar subregions in MDD and suggest that the limbic-cortical-striato-pallido-thalamic circuitry plays a crucial role in the early stages of MDD.
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Affiliation(s)
- Lihua Qiu
- From the Huaxi MR Research Centre (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Qiu, Chen, Lui, Huang, Gong); the Department of Radiology, The Second People's Hospital of Yibin, Yibin, China (Qiu); the National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China (Xia, Yuan, He); the Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China (Xia, He); the IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China (Xia, He); the Department of Psychiatry, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Kuang); the Department of Oncology, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Bi); the National Engineering Research Centre for Biomaterials, Sichuan University, Chengdu, Sichuan, China (Ai, Gu)
| | - Mingrui Xia
- From the Huaxi MR Research Centre (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Qiu, Chen, Lui, Huang, Gong); the Department of Radiology, The Second People's Hospital of Yibin, Yibin, China (Qiu); the National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China (Xia, Yuan, He); the Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China (Xia, He); the IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China (Xia, He); the Department of Psychiatry, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Kuang); the Department of Oncology, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Bi); the National Engineering Research Centre for Biomaterials, Sichuan University, Chengdu, Sichuan, China (Ai, Gu)
| | - Bochao Cheng
- From the Huaxi MR Research Centre (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Qiu, Chen, Lui, Huang, Gong); the Department of Radiology, The Second People's Hospital of Yibin, Yibin, China (Qiu); the National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China (Xia, Yuan, He); the Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China (Xia, He); the IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China (Xia, He); the Department of Psychiatry, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Kuang); the Department of Oncology, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Bi); the National Engineering Research Centre for Biomaterials, Sichuan University, Chengdu, Sichuan, China (Ai, Gu)
| | - Lin Yuan
- From the Huaxi MR Research Centre (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Qiu, Chen, Lui, Huang, Gong); the Department of Radiology, The Second People's Hospital of Yibin, Yibin, China (Qiu); the National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China (Xia, Yuan, He); the Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China (Xia, He); the IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China (Xia, He); the Department of Psychiatry, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Kuang); the Department of Oncology, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Bi); the National Engineering Research Centre for Biomaterials, Sichuan University, Chengdu, Sichuan, China (Ai, Gu)
| | - Weihong Kuang
- From the Huaxi MR Research Centre (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Qiu, Chen, Lui, Huang, Gong); the Department of Radiology, The Second People's Hospital of Yibin, Yibin, China (Qiu); the National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China (Xia, Yuan, He); the Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China (Xia, He); the IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China (Xia, He); the Department of Psychiatry, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Kuang); the Department of Oncology, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Bi); the National Engineering Research Centre for Biomaterials, Sichuan University, Chengdu, Sichuan, China (Ai, Gu)
| | - Feng Bi
- From the Huaxi MR Research Centre (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Qiu, Chen, Lui, Huang, Gong); the Department of Radiology, The Second People's Hospital of Yibin, Yibin, China (Qiu); the National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China (Xia, Yuan, He); the Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China (Xia, He); the IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China (Xia, He); the Department of Psychiatry, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Kuang); the Department of Oncology, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Bi); the National Engineering Research Centre for Biomaterials, Sichuan University, Chengdu, Sichuan, China (Ai, Gu)
| | - Hua Ai
- From the Huaxi MR Research Centre (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Qiu, Chen, Lui, Huang, Gong); the Department of Radiology, The Second People's Hospital of Yibin, Yibin, China (Qiu); the National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China (Xia, Yuan, He); the Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China (Xia, He); the IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China (Xia, He); the Department of Psychiatry, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Kuang); the Department of Oncology, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Bi); the National Engineering Research Centre for Biomaterials, Sichuan University, Chengdu, Sichuan, China (Ai, Gu)
| | - Zhongwei Gu
- From the Huaxi MR Research Centre (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Qiu, Chen, Lui, Huang, Gong); the Department of Radiology, The Second People's Hospital of Yibin, Yibin, China (Qiu); the National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China (Xia, Yuan, He); the Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China (Xia, He); the IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China (Xia, He); the Department of Psychiatry, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Kuang); the Department of Oncology, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Bi); the National Engineering Research Centre for Biomaterials, Sichuan University, Chengdu, Sichuan, China (Ai, Gu)
| | - Su Lui
- From the Huaxi MR Research Centre (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Qiu, Chen, Lui, Huang, Gong); the Department of Radiology, The Second People's Hospital of Yibin, Yibin, China (Qiu); the National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China (Xia, Yuan, He); the Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China (Xia, He); the IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China (Xia, He); the Department of Psychiatry, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Kuang); the Department of Oncology, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Bi); the National Engineering Research Centre for Biomaterials, Sichuan University, Chengdu, Sichuan, China (Ai, Gu)
| | - Xiaoqi Huang
- From the Huaxi MR Research Centre (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Qiu, Chen, Lui, Huang, Gong); the Department of Radiology, The Second People's Hospital of Yibin, Yibin, China (Qiu); the National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China (Xia, Yuan, He); the Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China (Xia, He); the IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China (Xia, He); the Department of Psychiatry, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Kuang); the Department of Oncology, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Bi); the National Engineering Research Centre for Biomaterials, Sichuan University, Chengdu, Sichuan, China (Ai, Gu)
| | - Yong He
- From the Huaxi MR Research Centre (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Qiu, Chen, Lui, Huang, Gong); the Department of Radiology, The Second People's Hospital of Yibin, Yibin, China (Qiu); the National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China (Xia, Yuan, He); the Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China (Xia, He); the IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China (Xia, He); the Department of Psychiatry, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Kuang); the Department of Oncology, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Bi); the National Engineering Research Centre for Biomaterials, Sichuan University, Chengdu, Sichuan, China (Ai, Gu)
| | - Qiyong Gong
- From the Huaxi MR Research Centre (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Qiu, Chen, Lui, Huang, Gong); the Department of Radiology, The Second People's Hospital of Yibin, Yibin, China (Qiu); the National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China (Xia, Yuan, He); the Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China (Xia, He); the IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China (Xia, He); the Department of Psychiatry, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Kuang); the Department of Oncology, State Key Lab of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, China (Bi); the National Engineering Research Centre for Biomaterials, Sichuan University, Chengdu, Sichuan, China (Ai, Gu)
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21
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Gejl M, Gjedde A, Brock B, Møller A, van Duinkerken E, Haahr HL, Hansen CT, Chu PL, Stender-Petersen KL, Rungby J. Effects of hypoglycaemia on working memory and regional cerebral blood flow in type 1 diabetes: a randomised, crossover trial. Diabetologia 2018; 61:551-561. [PMID: 29188338 PMCID: PMC6448973 DOI: 10.1007/s00125-017-4502-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 10/03/2017] [Indexed: 01/31/2023]
Abstract
AIMS/HYPOTHESIS The aim of this randomised, crossover trial was to compare cognitive functioning and associated brain activation patterns during hypoglycaemia (plasma glucose [PG] just below 3.1 mmol/l) and euglycaemia in individuals with type 1 diabetes mellitus. METHODS In this patient-blinded, crossover study, 26 participants with type 1 diabetes mellitus attended two randomised experimental visits: one hypoglycaemic clamp (PG 2.8 ± 0.2 mmol/l, approximate duration 55 min) and one euglycaemic clamp (PG 5.5 mmol/l ± 10%). PG levels were maintained by hyperinsulinaemic glucose clamping. Cognitive functioning was assessed during hypoglycaemia and euglycaemia conditions using a modified version of the digit symbol substitution test (mDSST) and control DSST (cDSST). Simultaneously, regional cerebral blood flow (rCBF) was measured in pre-specified brain regions by six H215O-positron emission tomographies (PET) per session. RESULTS Working memory was impaired during hypoglycaemia as indicated by a statistically significantly lower mDSST score (estimated treatment difference [ETD] -0.63 [95% CI -1.13, -0.14], p = 0.014) and a statistically significantly longer response time (ETD 2.86 s [7%] [95% CI 0.67, 5.05], p = 0.013) compared with euglycaemia. During hypoglycaemia, mDSST task performance was associated with increased activity in the frontal lobe regions, superior parietal lobe and thalamus, and decreased activity in the temporal lobe regions (p < 0.05). Working memory activation (mDSST - cDSST) statistically significantly increased blood flow in the striatum during hypoglycaemia (ETD 0.0374% [95% CI 0.0157, 0.0590], p = 0.002). CONCLUSIONS/INTERPRETATION During hypoglycaemia (mean PG 2.9 mmol/l), working memory performance was impaired. Altered performance was associated with significantly increased blood flow in the striatum, a part of the basal ganglia implicated in regulating motor functions, memory, language and emotion. TRIAL REGISTRATION NCT01789593, clinicaltrials.gov FUNDING: This study was funded by Novo Nordisk.
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Affiliation(s)
- Michael Gejl
- Department of Biomedicine, Aarhus University, Bartholins Allé 6, Building 1242, 8000, Aarhus C, Denmark.
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark.
| | - Albert Gjedde
- Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Medicine, University of Southern Denmark, Odense, Denmark
| | - Birgitte Brock
- Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark
- Steno Diabetes Center Copenhagen, Gentofte, Denmark
| | - Arne Møller
- Department of Biomedicine, Aarhus University, Bartholins Allé 6, Building 1242, 8000, Aarhus C, Denmark
- PET-Center, Department of Nuclear Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Eelco van Duinkerken
- VU University Medical Centre, Amsterdam, the Netherlands
- Pontifícia Universidade Católica, Rio de Janeiro, Brazil
| | | | | | | | | | - Jørgen Rungby
- Department of Biomedicine, Aarhus University, Bartholins Allé 6, Building 1242, 8000, Aarhus C, Denmark
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
- Department of Endocrinology IC, Bispebjerg University Hospital, Bispebjerg, Copenhagen, Denmark
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22
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Kozlowska K, Spooner CJ, Palmer DM, Harris A, Korgaonkar MS, Scher S, Williams LM. "Motoring in idle": The default mode and somatomotor networks are overactive in children and adolescents with functional neurological symptoms. Neuroimage Clin 2018; 18:730-743. [PMID: 29876262 PMCID: PMC5987846 DOI: 10.1016/j.nicl.2018.02.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 01/19/2018] [Accepted: 02/02/2018] [Indexed: 12/20/2022]
Abstract
Objective Children and adolescents with functional neurological symptom disorder (FND) present with diverse neurological symptoms not explained by a disease process. Functional neurological symptoms have been conceptualized as somatoform dissociation, a disruption of the brain's intrinsic organization and reversion to a more primitive level of function. We used EEG to investigate neural function and functional brain organization in children/adolescents with FND. Method EEG was recorded in the resting eyes-open condition in 57 patients (aged 8.5-18 years) and 57 age- and sex-matched healthy controls. Using a topographical map, EEG power data were quantified for regions of interest that define the default mode network (DMN), salience network, and somatomotor network. Source localization was examined using low-resolution brain electromagnetic tomography (LORETA). The contributions of chronic pain and arousal as moderators of differences in EEG power were also examined. Results Children/adolescents with FND had excessive theta and delta power in electrode clusters corresponding to the DMN-both anteriorly (dorsomedial prefrontal cortex [dmFPC]) and posteriorly (posterior cingulate cortex [PCC], precuneus, and lateral parietal cortex)-and in the premotor/supplementary motor area (SMA) region. There was a trend toward increased theta and delta power in the salience network. LORETA showed activation across all three networks in all power bands and localized neural sources to the dorsal anterior cingulate cortex/dmPFC, mid cingulate cortex, PCC/precuneus, and SMA. Pain and arousal contributed to slow wave power increases in all three networks. Conclusions These findings suggest that children and adolescents with FND are characterized by overactivation of intrinsic resting brain networks involved in threat detection, energy regulation, and preparation for action.
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Affiliation(s)
- Kasia Kozlowska
- The Children's Hospital at Westmead, Psychological Medicine, Locked Bag 4001, Westmead, NSW 2145, Australia; The Brain Dynamics Centre, Westmead Institute for Medical Research, 176 Hawkesbury Rd, Westmead, NSW 2145, Australia; The University of Sydney, Sydney, Australia.
| | | | - Donna M Palmer
- The Brain Dynamics Centre, Westmead Institute for Medical Research, 176 Hawkesbury Rd, Westmead, NSW 2145, Australia; The University of Sydney, Sydney, Australia.
| | - Anthony Harris
- The Brain Dynamics Centre, Westmead Institute for Medical Research, 176 Hawkesbury Rd, Westmead, NSW 2145, Australia; The University of Sydney, Sydney, Australia; Westmead Hospital Psychiatry Department, Darcy Rd, Westmead, NSW 2145, Australia.
| | - Mayuresh S Korgaonkar
- The Brain Dynamics Centre, Westmead Institute for Medical Research, 176 Hawkesbury Rd, Westmead, NSW 2145, Australia; The University of Sydney, Sydney, Australia.
| | - Stephen Scher
- The University of Sydney, Sydney, Australia; Department of Psychiatry, Harvard Medical School, McLean Hospital, Belmont, MA, USA.
| | - Leanne M Williams
- Psychiatry and Behavioral Sciences, Stanford University, VA Palo Alto (Sierra-Pacific MIRECC) 401 Quarry Rd, United States.
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23
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Wiegers EC, Becker KM, Rooijackers HM, von Samson-Himmelstjerna FC, Tack CJ, Heerschap A, de Galan BE, van der Graaf M. Cerebral blood flow response to hypoglycemia is altered in patients with type 1 diabetes and impaired awareness of hypoglycemia. J Cereb Blood Flow Metab 2017; 37:1994-2001. [PMID: 27389175 PMCID: PMC5464695 DOI: 10.1177/0271678x16658914] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
It is unclear whether cerebral blood flow responses to hypoglycemia are altered in people with type 1 diabetes and impaired awareness of hypoglycemia. The aim of this study was to investigate the effect of hypoglycemia on both global and regional cerebral blood flow in type 1 diabetes patients with impaired awareness of hypoglycemia, type 1 diabetes patients with normal awareness of hypoglycemia and healthy controls ( n = 7 per group). The subjects underwent a hyperinsulinemic euglycemic-hypoglycemic glucose clamp in a 3 T MR system. Global and regional changes in cerebral blood flow were determined by arterial spin labeling magnetic resonance imaging, at the end of both glycemic phases. Hypoglycemia generated typical symptoms in patients with type 1 diabetes and normal awareness of hypoglycemia and healthy controls, but not in patients with impaired awareness of hypoglycemia. Conversely, hypoglycemia increased global cerebral blood flow in patients with impaired awareness of hypoglycemia, which was not observed in the other two groups. Regionally, hypoglycemia caused a redistribution of cerebral blood flow towards the thalamus of both patients with normal awareness of hypoglycemia and healthy controls, consistent with activation of brain regions associated with the autonomic response to hypoglycemia. No such redistribution was found in the patients with impaired awareness of hypoglycemia. An increase in global cerebral blood flow may enhance nutrient supply to the brain, hence suppressing symptomatic awareness of hypoglycemia. Altogether these results suggest that changes in cerebral blood flow during hypoglycemia contribute to impaired awareness of hypoglycemia.
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Affiliation(s)
- Evita C Wiegers
- 1 Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Kirsten M Becker
- 1 Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Hanne M Rooijackers
- 2 Department of Internal Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Federico C von Samson-Himmelstjerna
- 3 Fraunhofer MEVIS, Institute for Medical Image Computing, Bremen, Germany.,4 Faculty of Physics and Electronics, University of Bremen, Bremen, Germany
| | - Cees J Tack
- 2 Department of Internal Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Arend Heerschap
- 1 Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Bastiaan E de Galan
- 2 Department of Internal Medicine, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Marinette van der Graaf
- 1 Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, the Netherlands.,5 Department of Pediatrics, Radboud University Medical Center, Nijmegen, the Netherlands
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24
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Mikeladze M, Hedrington MS, Joy N, Tate DB, Younk LM, Davis I, Davis SN. Acute Effects of Oral Dehydroepiandrosterone on Counterregulatory Responses During Repeated Hypoglycemia in Healthy Humans. Diabetes 2016; 65:3161-70. [PMID: 27486235 PMCID: PMC5033266 DOI: 10.2337/db16-0406] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Accepted: 07/15/2016] [Indexed: 11/13/2022]
Abstract
We tested the hypothesis that acute administration of oral dehydroepiandrosterone (DHEA) during episodes of repeated hypoglycemia can prevent the development of hypoglycemia-associated neuroendocrine and autonomic failure in healthy humans. Twenty-seven individuals (16 men, 11 women) participated in two separate randomized, single-blind, 2-day protocols. Day 1 consisted of morning and afternoon 2-h hypoglycemic clamps (2.9 mmol/L) with 800 mg of DHEA or placebo administered before each clamp. Day 2 consisted of a single 2-h hypoglycemic clamp (2.9 mmol/L) following either DHEA (1,600 mg) or placebo. A 3-tritiated glucose was used to determine glucose kinetics during hypoglycemia on day 2. Antecedent hypoglycemia with placebo resulted in significant reductions of epinephrine, norepinephrine, glucagon, growth hormone, cortisol, endogenous glucose production, and lipolytic and symptom responses. During hypoglycemia on day 2, DHEA prevented blunting of all neuroendocrine, autonomic nervous system (ANS), metabolic, and symptom counterregulatory responses following hypoglycemia on day 1. In summary, DHEA can acutely preserve a wide range of key neuroendocrine, ANS, and metabolic counterregulatory homeostatic responses during repeated hypoglycemia. We conclude that DHEA may have acute effects to protect against hypoglycemia-associated neuroendocrine and autonomic failure in healthy humans.
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Affiliation(s)
- Maia Mikeladze
- Department of Medicine, University of Maryland, Baltimore, MD
| | | | - Nino Joy
- Department of Medicine, University of Maryland, Baltimore, MD
| | - Donna B Tate
- Department of Medicine, University of Maryland, Baltimore, MD
| | - Lisa M Younk
- Department of Medicine, University of Maryland, Baltimore, MD
| | - Ian Davis
- Department of Medicine, University of Maryland, Baltimore, MD
| | - Stephen N Davis
- Department of Medicine, University of Maryland, Baltimore, MD
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25
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Burks JD, Bonney PA, Conner AK, Glenn CA, Briggs RG, Battiste JD, McCoy T, O'Donoghue DL, Wu DH, Sughrue ME. A method for safely resecting anterior butterfly gliomas: the surgical anatomy of the default mode network and the relevance of its preservation. J Neurosurg 2016; 126:1795-1811. [DOI: 10.3171/2016.5.jns153006] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVEGliomas invading the anterior corpus callosum are commonly deemed unresectable due to an unacceptable risk/benefit ratio, including the risk of abulia. In this study, the authors investigated the anatomy of the cingulum and its connectivity within the default mode network (DMN). A technique is described involving awake subcortical mapping with higher attention tasks to preserve the cingulum and reduce the incidence of postoperative abulia for patients with so-called butterfly gliomas.METHODSThe authors reviewed clinical data on all patients undergoing glioma surgery performed by the senior author during a 4-year period at the University of Oklahoma Health Sciences Center. Forty patients were identified who underwent surgery for butterfly gliomas. Each patient was designated as having undergone surgery either with or without the use of awake subcortical mapping and preservation of the cingulum. Data recorded on these patients included the incidence of abulia/akinetic mutism. In the context of the study findings, the authors conducted a detailed anatomical study of the cingulum and its role within the DMN using postmortem fiber tract dissections of 10 cerebral hemispheres and in vivo diffusion tractography of 10 healthy subjects.RESULTSForty patients with butterfly gliomas were treated, 25 (62%) with standard surgical methods and 15 (38%) with awake subcortical mapping and preservation of the cingulum. One patient (1/15, 7%) experienced postoperative abulia following surgery with the cingulum-sparing technique. Greater than 90% resection was achieved in 13/15 (87%) of these patients.CONCLUSIONSThis study presents evidence that anterior butterfly gliomas can be safely removed using a novel, attention-task based, awake brain surgery technique that focuses on preserving the anatomical connectivity of the cingulum and relevant aspects of the cingulate gyrus.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Dee H. Wu
- 4Radiological Sciences, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
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26
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Motor, cognitive, and affective areas of the cerebral cortex influence the adrenal medulla. Proc Natl Acad Sci U S A 2016; 113:9922-7. [PMID: 27528671 DOI: 10.1073/pnas.1605044113] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Modern medicine has generally viewed the concept of "psychosomatic" disease with suspicion. This view arose partly because no neural networks were known for the mind, conceptually associated with the cerebral cortex, to influence autonomic and endocrine systems that control internal organs. Here, we used transneuronal transport of rabies virus to identify the areas of the primate cerebral cortex that communicate through multisynaptic connections with a major sympathetic effector, the adrenal medulla. We demonstrate that two broad networks in the cerebral cortex have access to the adrenal medulla. The larger network includes all of the cortical motor areas in the frontal lobe and portions of somatosensory cortex. A major component of this network originates from the supplementary motor area and the cingulate motor areas on the medial wall of the hemisphere. These cortical areas are involved in all aspects of skeletomotor control from response selection to motor preparation and movement execution. The second, smaller network originates in regions of medial prefrontal cortex, including a major contribution from pregenual and subgenual regions of anterior cingulate cortex. These cortical areas are involved in higher-order aspects of cognition and affect. These results indicate that specific multisynaptic circuits exist to link movement, cognition, and affect to the function of the adrenal medulla. This circuitry may mediate the effects of internal states like chronic stress and depression on organ function and, thus, provide a concrete neural substrate for some psychosomatic illness.
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27
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Medial cerebellar nucleus projects to feeding-related neurons in the ventromedial hypothalamic nucleus in rats. Brain Struct Funct 2016; 222:957-971. [DOI: 10.1007/s00429-016-1257-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 06/20/2016] [Indexed: 12/20/2022]
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28
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Fan AP, Jahanian H, Holdsworth SJ, Zaharchuk G. Comparison of cerebral blood flow measurement with [15O]-water positron emission tomography and arterial spin labeling magnetic resonance imaging: A systematic review. J Cereb Blood Flow Metab 2016; 36:842-61. [PMID: 26945019 PMCID: PMC4853843 DOI: 10.1177/0271678x16636393] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Revised: 01/19/2016] [Accepted: 02/04/2016] [Indexed: 11/16/2022]
Abstract
Noninvasive imaging of cerebral blood flow provides critical information to understand normal brain physiology as well as to identify and manage patients with neurological disorders. To date, the reference standard for cerebral blood flow measurements is considered to be positron emission tomography using injection of the [(15)O]-water radiotracer. Although [(15)O]-water has been used to study brain perfusion under normal and pathological conditions, it is not widely used in clinical settings due to the need for an on-site cyclotron, the invasive nature of arterial blood sampling, and experimental complexity. As an alternative, arterial spin labeling is a promising magnetic resonance imaging technique that magnetically labels arterial blood as it flows into the brain to map cerebral blood flow. As arterial spin labeling becomes more widely adopted in research and clinical settings, efforts have sought to standardize the method and validate its cerebral blood flow values against positron emission tomography-based cerebral blood flow measurements. The purpose of this work is to critically review studies that performed both [(15)O]-water positron emission tomography and arterial spin labeling to measure brain perfusion, with the aim of better understanding the accuracy and reproducibility of arterial spin labeling relative to the positron emission tomography reference standard.
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Affiliation(s)
- Audrey P Fan
- Department of Radiology, Stanford University, Stanford, CA, USA
| | | | | | - Greg Zaharchuk
- Department of Radiology, Stanford University, Stanford, CA, USA
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The Effects of Insulin-Induced Hypoglycaemia on Tyrosine Hydroxylase Phosphorylation in Rat Brain and Adrenal Gland. Neurochem Res 2016; 41:1612-24. [PMID: 26935743 DOI: 10.1007/s11064-016-1875-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Accepted: 02/18/2016] [Indexed: 12/16/2022]
Abstract
In this study we investigated the effects of insulin-induced hypoglycaemia on tyrosine hydroxylase (TH) protein and TH phosphorylation in the adrenal gland, C1 cell group, locus coeruleus (LC) and midbrain dopaminergic cell groups that are thought to play a role in response to hypoglycaemia and compared the effects of different concentrations of insulin in rats. Insulin (1 and 10 U/kg) treatment caused similar reductions in blood glucose concentration (from 7.5-9 to 2-3 mmol/L); however, plasma adrenaline concentration was increased 20-30 fold in response to 10 U/kg insulin and only 14 fold following 1 U/kg. Time course studies (at 10 U/kg insulin) revealed that in the adrenal gland, Ser31 phosphorylation was increased between 30 and 90 min (4-5 fold), implying that TH was activated to increase catecholamine synthesis in adrenal medulla to replenish the stores. In the brain, Ser19 phosphorylation was limited to certain dopaminergic groups in the midbrain, while Ser31 phosphorylation was increased in most catecholaminergic regions at 60 min (1.3-2 fold), suggesting that Ser31 phosphorylation may be an important mechanism to maintain catecholamine synthesis in the brain. Comparing the effects of 1 and 10 U/kg insulin revealed that Ser31 phosphorylation was increased to similar extent in the adrenal gland and C1 cell group in response to both doses whereas Ser31 and Ser19 phosphorylation were only increased in response to 1 U/kg insulin in LC and in response to 10 U/kg insulin in most midbrain regions. Thus, the adrenal gland and some catecholaminergic brain regions become activated in response to insulin administration and brain catecholamines may be important for initiation of physiological defences against insulin-induced hypoglycaemia.
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Rooijackers HMM, Wiegers EC, Tack CJ, van der Graaf M, de Galan BE. Brain glucose metabolism during hypoglycemia in type 1 diabetes: insights from functional and metabolic neuroimaging studies. Cell Mol Life Sci 2016; 73:705-22. [PMID: 26521082 PMCID: PMC4735263 DOI: 10.1007/s00018-015-2079-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 10/16/2015] [Accepted: 10/20/2015] [Indexed: 12/30/2022]
Abstract
Hypoglycemia is the most frequent complication of insulin therapy in patients with type 1 diabetes. Since the brain is reliant on circulating glucose as its main source of energy, hypoglycemia poses a threat for normal brain function. Paradoxically, although hypoglycemia commonly induces immediate decline in cognitive function, long-lasting changes in brain structure and cognitive function are uncommon in patients with type 1 diabetes. In fact, recurrent hypoglycemia initiates a process of habituation that suppresses hormonal responses to and impairs awareness of subsequent hypoglycemia, which has been attributed to adaptations in the brain. These observations sparked great scientific interest into the brain's handling of glucose during (recurrent) hypoglycemia. Various neuroimaging techniques have been employed to study brain (glucose) metabolism, including PET, fMRI, MRS and ASL. This review discusses what is currently known about cerebral metabolism during hypoglycemia, and how findings obtained by functional and metabolic neuroimaging techniques contributed to this knowledge.
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Affiliation(s)
- Hanne M M Rooijackers
- Department of Internal Medicine 463, Radboud University Medical Center, PO Box 9101, 6500 HB, Nijmegen, The Netherlands.
| | - Evita C Wiegers
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Cees J Tack
- Department of Internal Medicine 463, Radboud University Medical Center, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
| | - Marinette van der Graaf
- Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
- Department of Pediatrics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Bastiaan E de Galan
- Department of Internal Medicine 463, Radboud University Medical Center, PO Box 9101, 6500 HB, Nijmegen, The Netherlands
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Rao R, Ennis K, Mitchell EP, Tran PV, Gewirtz JC. Recurrent Moderate Hypoglycemia Suppresses Brain-Derived Neurotrophic Factor Expression in the Prefrontal Cortex and Impairs Sensorimotor Gating in the Posthypoglycemic Period in Young Rats. Dev Neurosci 2016; 38:74-82. [PMID: 26820887 DOI: 10.1159/000442878] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 11/29/2015] [Indexed: 01/04/2023] Open
Abstract
Recurrent hypoglycemia is common in infants and children. In developing rat models, recurrent moderate hypoglycemia leads to neuronal injury in the medial prefrontal cortex. To understand the effects beyond neuronal injury, 3-week-old male rats were subjected to 5 episodes of moderate hypoglycemia (blood glucose concentration, approx. 30 mg/dl for 90 min) once daily from postnatal day 24 to 28. Neuronal injury was determined using Fluoro-Jade B histochemistry on postnatal day 29. The effects on brain-derived neurotrophic factor (BDNF) and its cognate receptor, tyrosine kinase receptor B (TrkB) expression, which is critical for prefrontal cortex development, were determined on postnatal day 29 and at adulthood. The effects on prefrontal cortex-mediated function were determined by assessing the prepulse inhibition of the acoustic startle reflex on postnatal day 29 and 2 weeks later, and by testing for fear-potentiated startle at adulthood. Recurrent hypoglycemia led to neuronal injury confined primarily to the medial prefrontal cortex. BDNF/TrkB expression in the prefrontal cortex was suppressed on postnatal day 29 and was accompanied by lower prepulse inhibition, suggesting impaired sensorimotor gating. Following the cessation of recurrent hypoglycemia, the prepulse inhibition had recovered at 2 weeks. BDNF/TrkB expression in the prefrontal cortex had normalized and fear-potentiated startle was intact at adulthood. Recurrent moderate hypoglycemia during development has significant adverse effects on the prefrontal cortex in the posthypoglycemic period.
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Cerebral Blood Flow and Metabolism. Stroke 2016. [DOI: 10.1016/b978-0-323-29544-4.00003-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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33
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Jarrahi B, Mantini D, Balsters JH, Michels L, Kessler TM, Mehnert U, Kollias SS. Differential functional brain network connectivity during visceral interoception as revealed by independent component analysis of fMRI TIME-series. Hum Brain Mapp 2015; 36:4438-68. [PMID: 26249369 DOI: 10.1002/hbm.22929] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 07/20/2015] [Accepted: 07/27/2015] [Indexed: 12/15/2022] Open
Abstract
Influential theories of brain-viscera interactions propose a central role for interoception in basic motivational and affective feeling states. Recent neuroimaging studies have underlined the insula, anterior cingulate, and ventral prefrontal cortices as the neural correlates of interoception. However, the relationships between these distributed brain regions remain unclear. In this study, we used spatial independent component analysis (ICA) and functional network connectivity (FNC) approaches to investigate time course correlations across the brain regions during visceral interoception. Functional magnetic resonance imaging (fMRI) was performed in thirteen healthy females who underwent viscerosensory stimulation of bladder as a representative internal organ at different prefill levels, i.e., no prefill, low prefill (100 ml saline), and high prefill (individually adapted to the sensations of persistent strong desire to void), and with different infusion temperatures, i.e., body warm (∼37°C) or ice cold (4-8°C) saline solution. During Increased distention pressure on the viscera, the insula, striatum, anterior cingulate, ventromedial prefrontal cortex, amygdalo-hippocampus, thalamus, brainstem, and cerebellar components showed increased activation. A second group of components encompassing the insula and anterior cingulate, dorsolateral prefrontal and posterior parietal cortices and temporal-parietal junction showed increased activity with innocuous temperature stimulation of bladder mucosa. Significant differences in the FNC were found between the insula and amygdalo-hippocampus, the insula and ventromedial prefrontal cortex, and the ventromedial prefrontal cortex and temporal-parietal junction as the distention pressure on the viscera increased. These results provide new insight into the supraspinal processing of visceral interoception originating from an internal organ.
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Affiliation(s)
- Behnaz Jarrahi
- Clinic for Neuroradiology, University Hospital, Zurich, Switzerland.,Department of Information Technology and Electrical Engineering, Institute for Biomedical Engineering, Federal Institute of Technology (ETH), Zurich, Switzerland.,Neuro-Urology Spinal Cord Injury Center and Research, Balgrist University Hospital, Zurich, Switzerland.,Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles (UCLA), California.,Neuroscience Center Zurich, University and ETH, Zurich, Switzerland
| | - Dante Mantini
- Neuroscience Center Zurich, University and ETH, Zurich, Switzerland.,Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom.,Department of Health Sciences and Technology, Neural Control of Movement Laboratory, ETH Zurich, Switzerland
| | - Joshua Henk Balsters
- Department of Health Sciences and Technology, Neural Control of Movement Laboratory, ETH Zurich, Switzerland
| | - Lars Michels
- Clinic for Neuroradiology, University Hospital, Zurich, Switzerland.,Center for MR-Research, University Children's Hospital, Zurich, Switzerland
| | - Thomas M Kessler
- Neuro-Urology Spinal Cord Injury Center and Research, Balgrist University Hospital, Zurich, Switzerland
| | - Ulrich Mehnert
- Neuro-Urology Spinal Cord Injury Center and Research, Balgrist University Hospital, Zurich, Switzerland
| | - Spyros S Kollias
- Clinic for Neuroradiology, University Hospital, Zurich, Switzerland.,Neuroscience Center Zurich, University and ETH, Zurich, Switzerland
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Intraoperative Glycemic Control to Prevent Delirium after Cardiac Surgery: Steering a Course between Scylla and Charybdis. Anesthesiology 2015; 122:1186-8. [PMID: 25844843 DOI: 10.1097/aln.0000000000000670] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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35
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Abstract
The brain's default mode network consists of discrete, bilateral and symmetrical cortical areas, in the medial and lateral parietal, medial prefrontal, and medial and lateral temporal cortices of the human, nonhuman primate, cat, and rodent brains. Its discovery was an unexpected consequence of brain-imaging studies first performed with positron emission tomography in which various novel, attention-demanding, and non-self-referential tasks were compared with quiet repose either with eyes closed or with simple visual fixation. The default mode network consistently decreases its activity when compared with activity during these relaxed nontask states. The discovery of the default mode network reignited a longstanding interest in the significance of the brain's ongoing or intrinsic activity. Presently, studies of the brain's intrinsic activity, popularly referred to as resting-state studies, have come to play a major role in studies of the human brain in health and disease. The brain's default mode network plays a central role in this work.
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Affiliation(s)
- Marcus E Raichle
- Washington University School of Medicine, St. Louis, Missouri 63110;
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36
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Zhang L, Duan H, Qin S, Yuan Y, Buchanan TW, Zhang K, Wu J. High cortisol awakening response is associated with impaired error monitoring and decreased post-error adjustment. Stress 2015; 18:561-8. [PMID: 26181101 DOI: 10.3109/10253890.2015.1058356] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The cortisol awakening response (CAR), a rapid increase in cortisol levels following morning awakening, is an important aspect of hypothalamic-pituitary-adrenocortical axis activity. Alterations in the CAR have been linked to a variety of mental disorders and cognitive function. However, little is known regarding the relationship between the CAR and error processing, a phenomenon that is vital for cognitive control and behavioral adaptation. Using high-temporal resolution measures of event-related potentials (ERPs) combined with behavioral assessment of error processing, we investigated whether and how the CAR is associated with two key components of error processing: error detection and subsequent behavioral adjustment. Sixty university students performed a Go/No-go task while their ERPs were recorded. Saliva samples were collected at 0, 15, 30 and 60 min after awakening on the two consecutive days following ERP data collection. The results showed that a higher CAR was associated with slowed latency of the error-related negativity (ERN) and a higher post-error miss rate. The CAR was not associated with other behavioral measures such as the false alarm rate and the post-correct miss rate. These findings suggest that high CAR is a biological factor linked to impairments of multiple steps of error processing in healthy populations, specifically, the automatic detection of error and post-error behavioral adjustment. A common underlying neural mechanism of physiological and cognitive control may be crucial for engaging in both CAR and error processing.
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Affiliation(s)
- Liang Zhang
- a Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences , Beijing , People's Republic of China
| | - Hongxia Duan
- a Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences , Beijing , People's Republic of China
- b University of Chinese Academy of Sciences , Beijing , People's Republic of China
| | - Shaozheng Qin
- c State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University , Beijing , People's Republic of China
- d Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University , Beijing , People's Republic of China , and
| | - Yiran Yuan
- a Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences , Beijing , People's Republic of China
- b University of Chinese Academy of Sciences , Beijing , People's Republic of China
| | - Tony W Buchanan
- e Department of Psychology , Saint Louis University , St. Louis, MO , USA
| | - Kan Zhang
- a Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences , Beijing , People's Republic of China
| | - Jianhui Wu
- a Key Laboratory of Behavioral Science, Institute of Psychology, Chinese Academy of Sciences , Beijing , People's Republic of China
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37
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Contoreggi C. Corticotropin releasing hormone and imaging, rethinking the stress axis. Nucl Med Biol 2014; 42:323-39. [PMID: 25573209 DOI: 10.1016/j.nucmedbio.2014.11.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Revised: 11/07/2014] [Accepted: 11/19/2014] [Indexed: 11/25/2022]
Abstract
The stress system provides integration of both neurochemical and somatic physiologic functions within organisms as an adaptive mechanism to changing environmental conditions throughout evolution. In mammals and primates the complexity and sophistication of these systems have surpassed other species in triaging neurochemical and physiologic signaling to maximize chances of survival. Corticotropin releasing hormone (CRH) and its related peptides and receptors have been identified over the last three decades and are fundamental molecular initiators of the stress response. They are crucial in the top down regulatory cascade over a myriad of neurochemical, neuroendocrine and sympathetic nervous system events. From neuroscience, we've seen that stress activation impacts behavior, endocrine and somatic physiology and influences neurochemical events that one can capture in real time with current imaging technologies. To delineate these effects one can demonstrate how the CRH neuronal networks infiltrate critical cognitive, emotive and autonomic regions of the central nervous system (CNS) with somatic effects. Abundant preclinical and clinical studies show inter-regulatory actions of CRH with multiple neurotransmitters/peptides. Stress, both acute and chronic has epigenetic effects which magnify genetic susceptibilities to alter neurochemistry; stress system activation can add critical variables in design and interpretation of basic and clinical neuroscience and related research. This review will attempt to provide an overview of the spectrum of known functions and speculative actions of CRH and stress responses in light of imaging technology and its interpretation. Metabolic and neuroreceptor positron emission/single photon tomography (PET/SPECT), functional magnetic resonance imaging (fMRI), anatomic MRI, diffusion tensor imaging (DTI), and proton magnetic resonance spectroscopy (pMRS) are technologies that can delineate basic mechanisms of neurophysiology and pharmacology. Stress modulates the myriad of neurochemical and networks within and controlled through the central and peripheral nervous system and the effects of stress activation on imaging will be highlighted.
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Affiliation(s)
- Carlo Contoreggi
- Intramural Research Program (IRP), National Institute on Drug Abuse (NIDA), National Institutes of Health (NIH), Baltimore, MD, 21224.
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38
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Chechko N, Vocke S, Habel U, Toygar T, Kuckartz L, Berthold-Losleben M, Laoutidis ZG, Orfanos S, Wassenberg A, Karges W, Schneider F, Kohn N. Effects of overnight fasting on working memory-related brain network: an fMRI study. Hum Brain Mapp 2014; 36:839-51. [PMID: 25393934 DOI: 10.1002/hbm.22668] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 10/05/2014] [Accepted: 10/14/2014] [Indexed: 12/21/2022] Open
Abstract
Glucose metabolism serves as the central source of energy for the human brain. Little is known about the effects of blood glucose level (BGL) on higher-order cognitive functions within a physiological range (e.g., after overnight fasting). In this randomized, placebo-controlled, double blind study, we assessed the impact of overnight fasting (14 h) on brain activation during a working memory task. We sought to mimic BGLs that occur naturally in healthy humans after overnight fasting. After standardized periods of food restriction, 40 (20 male) healthy participants were randomly assigned to receive either glucagon to balance the BGL or placebo (NaCl). A parametric fMRI paradigm, including 2-back and 0-back tasks, was used. Subclinically low BGL following overnight fasting was found to be linked to reduced involvement of the bilateral dorsal midline thalamus and the bilateral basal ganglia, suggesting high sensitivity of those regions to minimal changes in BGLs. Our results indicate that overnight fasting leads to physiologically low levels of glucose, impacting brain activation during working memory tasks even when there are no differences in cognitive performance.
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Affiliation(s)
- Natalia Chechko
- Department of Psychiatry, Psychotherapy and Psychosomatic Medicine, RWTH Aachen University, Aachen, Germany; JARA Brain - Translational Brain Medicine, Jülich - Aachen, Germany
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Pitchaimani V, Arumugam S, Thandavarayan RA, Karuppagounder V, Sreedhar R, Afrin R, Harima M, Suzuki H, Miyashita S, Nomoto M, Sone H, Suzuki K, Watanabe K. Fasting mediated increase in p-BADser155 and p-AKTser473 in the prefrontal cortex of mice. Neurosci Lett 2014; 579:134-9. [DOI: 10.1016/j.neulet.2014.07.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 06/24/2014] [Accepted: 07/08/2014] [Indexed: 11/17/2022]
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40
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Arbelaez AM, Semenkovich K, Hershey T. Glycemic extremes in youth with T1DM: the structural and functional integrity of the developing brain. Pediatr Diabetes 2013; 14:541-53. [PMID: 24119040 PMCID: PMC3857606 DOI: 10.1111/pedi.12088] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Revised: 08/14/2013] [Accepted: 09/04/2013] [Indexed: 12/13/2022] Open
Abstract
The adult brain accounts for a disproportionally large percentage of the body’s total energy consumption (1). However, during brain development,energy demand is even higher, reaching the adult rate by age 2 and increasing to nearly twice the adult rate by age 10, followed by gradual reduction toward adult levels in the next decade (1,2). The dramatic changes in brain metabolism occurring over the first two decades of life coincide with the initial proliferation and then pruning of synapses to adult levels.The brain derives its energy almost exclusively from glucose and is largely driven by neuronal signaling, biosynthesis, and neuroprotection (3–6).Glucose homeostasis in the body is tightly regulated by a series of hormones and physiologic responses. As a result, hypoglycemia and hyperglycemia are rare occurrences in normal individuals, but they occur commonly inpatients with type 1 diabetes mellitus (T1DM) due to a dysfunction of peripheral glucose-insulin-glucagon responses and non-physiologic doses of exogenous insulin, which imperfectly mimic normal physiology. These extremes can occur more frequently in children and adolescents with T1DM due to the inadequacies of insulin replacement therapy, events leading to the diagnosis [prolonged untreated hyperglycemia and diabetic ketoacidosis (DKA)], and to behavioral factors interfering with optimal treatment. When faced with fluctuations in glucose supply the metabolism of the body and brain change dramatically, largely to conserve resources and, at a cost to other organs, to preserve brain function (7). However,if the normal physiological mechanisms that prevent these severe glucose fluctuations and maintain homeostasis are impaired, neuronal function and potentially viability can be affected (8–11).
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Affiliation(s)
- Ana Maria Arbelaez
- Department of Pediatrics, Washington University School of Medicine St. Louis, Missouri, United States, 63110
| | - Katherine Semenkovich
- Department of Pediatrics, Washington University School of Medicine St. Louis, Missouri, United States, 63110
| | - Tamara Hershey
- Department of Psychiatry, Washington University School of Medicine St. Louis, Missouri, United States, 63110,Department of Neurology, Washington University School of Medicine St. Louis, Missouri, United States, 63110,Department of Radiology, Washington University School of Medicine St. Louis, Missouri, United States, 63110
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41
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Affiliation(s)
- Philip E Cryer
- Division of Endocrinology, Metabolism and Lipid Research, Washington University School of Medicine, St. Louis, MO 63110, USA.
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Poeppl TB, Langguth B, Laird AR, Eickhoff SB. The functional neuroanatomy of male psychosexual and physiosexual arousal: a quantitative meta-analysis. Hum Brain Mapp 2013; 35:1404-21. [PMID: 23674246 DOI: 10.1002/hbm.22262] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 11/28/2012] [Accepted: 01/03/2013] [Indexed: 01/14/2023] Open
Abstract
Reproductive behavior is mandatory for conservation of species and mediated by a state of sexual arousal (SA), involving both complex mental processes and bodily reactions. An early neurobehavioral model of SA proposes cognitive, emotional, motivational, and autonomic components. In a comprehensive quantitative meta-analysis on previous neuroimaging findings, we provide here evidence for distinct brain networks underlying psychosexual and physiosexual arousal. Psychosexual (i.e., mental sexual) arousal recruits brain areas crucial for cognitive evaluation, top-down modulation of attention and exteroceptive sensory processing, relevance detection and affective evaluation, as well as regions implicated in the representation of urges and in triggering autonomic processes. In contrast, physiosexual (i.e., physiological sexual) arousal is mediated by regions responsible for regulation and monitoring of initiated autonomic processes and emotions and for somatosensory processing. These circuits are interconnected by subcortical structures (putamen and claustrum) that provide exchange of sensorimotor information and crossmodal processing between and within the networks. Brain deactivations may imply attenuation of introspective processes and social cognition, but be necessary to release intrinsic inhibition of SA.
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Affiliation(s)
- Timm B Poeppl
- Department of Psychiatry and Psychotherapy, University of Regensburg, Regensburg, Germany
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Arbeláez AM, Su Y, Thomas JB, Hauch AC, Hershey T, Ances BM. Comparison of regional cerebral blood flow responses to hypoglycemia using pulsed arterial spin labeling and positron emission tomography. PLoS One 2013; 8:e60085. [PMID: 23555895 PMCID: PMC3610825 DOI: 10.1371/journal.pone.0060085] [Citation(s) in RCA: 25] [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: 11/29/2012] [Accepted: 02/22/2013] [Indexed: 12/30/2022] Open
Abstract
Different brain regions sense and modulate the counterregulatory responses that can occur in response to declining plasma glucose levels. The aim of this study was to determine if changes in regional cerebral blood flow (rCBF) during hypoglycemia relative to euglycemia are similar for two imaging modalities–pulsed arterial spin labeling magnetic resonance imaging (PASL-MRI) and positron emission tomography (PET). Nine healthy non-diabetic participants underwent a hyperinsulinemic euglycemic (92±3 mg/dL) – hypoglycemic (53±1 mg/dL) clamp. Counterregulatory hormone levels were collected at each of these glycemic levels and rCBF measurements within the previously described network of hypoglycemia-responsive regions (thalamus, medial prefrontal cortex and globus pallidum) were obtained using PASL-MRI and [15O] water PET. In response to hypoglycemia, rCBF was significantly increased in the thalamus, medial prefrontal cortex, and globus pallidum compared to euglycemia for both PASL-MRI and PET methodologies. Both imaging techniques found similar increases in rCBF in the thalamus, medial prefrontal cortex, and globus pallidum in response to hypoglycemia. These brain regions may be involved in the physiologic and symptom responses to hypoglycemia. Compared to PET, PASL-MRI may provide a less invasive, less expensive method for assessing changes in rCBF during hypoglycemia without radiation exposure.
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Affiliation(s)
- Ana Maria Arbeláez
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO, USA.
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Abstract
The concept of hypoglycemia-associated autonomic failure (HAAF) in diabetes posits that recent antecedent hypoglycemia, as well as sleep or prior exercise, causes both defective glucose counterregulation (by attenuating the adrenomedullary epinephrine response, in the setting of absent insulin and glucagon responses) and hypoglycemia unawareness (by attenuating the sympathoadrenal, largely the sympathetic neural, response) and thus a vicious cycle of recurrent hypoglycemia. Albeit with different time courses, the pathophysiology of defense against hypoglycemia - no decrease in therapeutic insulin, no increase in glucagon and an attenuated increase in sympathoadrenal activity - is the same in type 1 diabetes and advanced type 2 diabetes. Hypoglycemia unawareness is reversible by 2-3 weeks of scrupulous avoidance of hypoglycemia in most affected patients. The pathophysiology of HAAF in diabetes explains why the incidence of hypoglycemia increases as patients approach the absolute endogenous insulin deficient end of the disease, provides a comprehensive set of risk factors including those indicative of HAAF, and leads logically to the practice of hypoglycemia risk factor reduction. Because of the risk of hypoglycemic mortality, presumably from cardiac arrhythmias, glycemic goals in diabetes should be individualized, based in part on the risk of hypoglycemia. By practicing hypoglycemia risk reduction - addressing the issue, applying the principles of aggressive glycemic therapy and considering both the conventional risk factors and those indicative of HAAF - it is possible to both improve glycemic control and reduce the risk of hypoglycemia in many patients with diabetes.
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Affiliation(s)
- Philip E Cryer
- Department of Medicine, Washington University in St. Louis and Barnes-Jewish Hospital, St. Louis, Missouri, USA.
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45
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Arbeláez AM, Rutlin JR, Hershey T, Powers WJ, Videen TO, Cryer PE. Thalamic activation during slightly subphysiological glycemia in humans. Diabetes Care 2012; 35:2570-4. [PMID: 22891254 PMCID: PMC3507561 DOI: 10.2337/dc12-0297] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE The central nervous system mechanisms of defenses against falling plasma glucose concentrations, and how they go awry and result in iatrogenic hypoglycemia in diabetes, are not known. Hypoglycemic plasma glucose concentrations of 55 mg/dL (3.0 mmol/L) cause symptoms, activate glucose counterregulatory systems, and increase synaptic activity in a network of brain regions including the dorsal midline thalamus in humans. We tested the hypothesis that slightly subphysiological plasma glucose concentrations of 65 mg/dL (3.6 mmol/L), which do not cause symptoms but do activate glucose counterregulatory systems, also activate brain synaptic activities. RESEARCH DESIGN AND METHODS We measured relative regional cerebral blood flow (rCBF), an index of synaptic activity, in predefined brain regions with [(15)O]water positron emission tomography, symptoms, and plasma epinephrine and glucagon concentrations during a 2-h euglycemic (90 mg/dL) to hypoglycemic (55 mg/dL) clamp (n = 20) or a 2-h euglycemic to slight subphysiological (65 mg/dL) clamp (n = 9) in healthy humans. RESULTS Clamped plasma glucose concentrations of 65 mg/dL did not cause hypoglycemic symptoms, but raised plasma epinephrine and glucagon concentrations and increased rCBF (P = 0.007) only in the dorsal midline thalamus. CONCLUSIONS Slightly subphysiological plasma glucose concentrations increase synaptic activity in the dorsal midline thalamus in humans.
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Affiliation(s)
- Ana María Arbeláez
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA.
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Hypoglycemia-induced increases in thalamic cerebral blood flow are blunted in subjects with type 1 diabetes and hypoglycemia unawareness. J Cereb Blood Flow Metab 2012; 32:2084-90. [PMID: 22892724 PMCID: PMC3494000 DOI: 10.1038/jcbfm.2012.117] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The thalamus has been found to be activated during the early phase of moderate hypoglycemia. Here, we tested the hypothesis that this region is less activated during hypoglycemia in subjects with type 1 diabetes (T1DM) and hypoglycemia unawareness relative to controls. Twelve controls (5 F/7 M, age 40 ± 14 years, body mass index 24.2 ± 2.7 kg/m(2)) and eleven patients (7 F/4 M, age 39 ± 13 years, body mass index 26.5 ± 4.4 kg/m(2)) with well-controlled T1DM (A1c 6.8 ± 0.4%) underwent a two-step hyperinsulinemic (2.0 mU/kg per minute) clamp. Cerebral blood flow (CBF) weighted images were acquired using arterial spin labeling to monitor cerebral activation in the midbrain regions. Blood glucose was first held at 95 mg/dL and then allowed to decrease to 50 mg/dL. The CBF image acquisition during euglycemia and hypoglycemia began within a few minutes of when the target blood glucose values were reached. Hypoglycemia unaware T1DM subjects displayed blunting of the physiologic CBF increase that occurs in the thalamus of healthy individuals during the early phase of moderate hypoglycemia. A positive correlation was observed between thalamic response and epinephrine response to hypoglycemia, suggesting that this region may be involved in the coordination of the counter regulatory response to hypoglycemia.
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Weaver C, Turner N, Hall J. Review of the neuroanatomic landscape implicated in glucose sensing and regulation of nutrient signaling: immunophenotypic localization of diabetes gene Tcf7l2 in the developing murine brain. J Chem Neuroanat 2012; 45:1-17. [PMID: 22796301 DOI: 10.1016/j.jchemneu.2012.06.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2012] [Revised: 06/12/2012] [Accepted: 06/19/2012] [Indexed: 01/25/2023]
Abstract
Genetic variants in the transcription factor 7-like 2(Tcf7l2) gene have been found to confer a significant risk of type 2 diabetes and attenuated insulin secretion. Based on its genomic wide association Tcf7l2 is considered the single most important predictor of diabetes to date. Previous studies of Tcf7l2 mRNA localization in the adult brain suggest a putative role of Tcf7l2 in the CNS regulation of energy homeostasis. The present study further characterizes the immunophenotypic distribution of peptide expression in the brains of Tcf7l2 progeny during developmental time periods between E12.5 and P1. Tcf7l2(-/-) is lethal beyond P1. Results show that while negligible TCF7L2 expression is found in the developing brains of Tcf7l2(-/-)mice, TCF7L2 protein is relatively widespread and robustly expressed in the brain by E18.5 and exhibits specific expression within neuronal populations and regions of the brain in Tcf7l2(+/-) and Tcf7l2(+/+) progeny. Strong immunophenotypic labeling was found in the diencephalic structure of the thalamus that suggests a role of Tcf7l2 in the development and maintenance of thalamic activity. Strongly expressed TCF7L2 was localized in select hypothalamic and preoptic nuclei indicative of Tcf7l2 function within neurons controlling energy balance. Definitive neuronal staining for TCF7L2 within nuclei of the brain stem and circumventricular organs extends TCF7L2 localization within autonomic neurons and its potential integration with autonomic function. In addition robust TCF7L2 expression was found in the tectal and tegmental structures of the superior and inferior colliculi as well as transient expression in neuroepithelium of the cerebral and hippocampal cortices of E16 and E18.5. Patterns of TCF7L2 peptide localization when compared to the adult protein synthetic chemical/anatomical landscape of glucose sensing exhibit a good correlational fit between its expression and regions, nuclei, and pathways regulating energy homeostasis via integration and response to peripheral endocrine, metabolic and neuronal signaling. TCF was also found co-localized with peptides that regulate energy homeostasis including AgRP, POMC and NPY. TCF7l2, some variants of which have been shown to impair GLP-1-induced insulin secretion, was also found co-localize with GLP-1 in adult TCF wild type progeny. Impaired Tcf7l2-mediated neural regulation may contribute to the risk and/or underlying pathophysiology of type 2 diabetes that has found high expression in genomic studies of Tcf7l2 variants.
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Affiliation(s)
- Cyprian Weaver
- Department of Medicine, University of Minnesota, Minneapolis, MN 55455, USA.
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Mood disorders. Transl Neurosci 2012. [DOI: 10.1017/cbo9780511980053.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Hurst P, Garfield AS, Marrow C, Heisler LK, Evans ML. Recurrent hypoglycemia is associated with loss of activation in rat brain cingulate cortex. Endocrinology 2012; 153:1908-14. [PMID: 22396449 PMCID: PMC3328129 DOI: 10.1210/en.2011-1827] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Accepted: 01/26/2012] [Indexed: 12/30/2022]
Abstract
A subset of people with diabetes fail to mount defensive counterregulatory responses (CRR) to hypoglycemia. Although the mechanisms by which this occurs remain unclear, recurrent exposure to hypoglycemia may be an important etiological factor. We hypothesized that loss of CRR to recurrent exposure to hypoglycemia represents a type of stress desensitization, in which limbic brain circuitry involved in modulating stress responses might be implicated. Here, we compared activation of limbic brain regions associated with stress desensitization during acute hypoglycemia (AH) and recurrent hypoglycemia (RH). Healthy Sprague Dawley rats were exposed to either acute or recurrent 3-d hypoglycemia. We also examined whether changes in neuronal activation were caused directly by the CRR itself by infusing epinephrine, glucagon, and corticosterone without hypoglycemia. AH increased neuronal activity as quantified by c-fos immunoreactivity (FOS-IR) in the cingulate cortex and associated ectorhinal and perirhinal cortices but not in an adjacent control area (primary somatosensory cortex). FOS-IR was not observed after hormone infusion, suggesting that AH-associated activation was caused by hypoglycemia rather than by CRR. Importantly, AH FOS-IR activation was significantly blunted in rats exposed to RH. In conclusion, analogous with other models of stress habituation, activation in the cingulate cortex and associated brain areas is lost with exposure to RH. Our data support the hypothesis that limbic brain areas may be associated with the loss of CRR to RH in diabetes.
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Affiliation(s)
- Paul Hurst
- University of Cambridge Metabolic Research Laboratories/Department of Medicine/National Institute for Health Research Cambridge Biomedical Research Centre, Cambridge CB2 0QQ, United Kingdom
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Weston C. Another major function of the anterior cingulate cortex: The representation of requirements. Neurosci Biobehav Rev 2012; 36:90-110. [DOI: 10.1016/j.neubiorev.2011.04.014] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2010] [Revised: 04/01/2011] [Accepted: 04/20/2011] [Indexed: 01/18/2023]
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