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Malin SK, Stewart NR, Ude AA, Alderman BL. Brain insulin resistance and cognitive function: influence of exercise. J Appl Physiol (1985) 2022; 133:1368-1380. [PMID: 36269295 PMCID: PMC9744647 DOI: 10.1152/japplphysiol.00375.2022] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 10/12/2022] [Accepted: 10/12/2022] [Indexed: 12/15/2022] Open
Abstract
Exercise has systemic health benefits in people, in part, through improving whole body insulin sensitivity. The brain is an insulin-sensitive organ that is often underdiscussed relative to skeletal muscle, liver, and adipose tissue. Although brain insulin action may have only subtle impacts on peripheral regulation of systemic glucose homeostasis, it is important for weight regulation as well as mental health. In fact, brain insulin signaling is also involved in processes that support healthy cognition. Furthermore, brain insulin resistance has been associated with age-related declines in memory and executive function as well as Alzheimer's disease pathology. Herein, we provide an overview of brain insulin sensitivity in relation to cognitive function from animal and human studies, with particular emphasis placed on the impact exercise may have on brain insulin sensitivity. Mechanisms discussed include mitochondrial function, brain growth factors, and neurogenesis, which collectively help combat obesity-related metabolic disease and Alzheimer's dementia.
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Affiliation(s)
- Steven K Malin
- Department of Kinesiology & Health, Rutgers University, New Brunswick, New Jersey
- Division of Endocrinology, Metabolism & Nutrition, Rutgers University, New Brunswick, New Jersey
- New Jersey Institute for Food, Nutrition and Health, Rutgers University, New Brunswick, New Jersey
- Institute of Translational Medicine and Science, Rutgers University, New Brunswick, New Jersey
| | - Nathan R Stewart
- Department of Kinesiology & Health, Rutgers University, New Brunswick, New Jersey
| | - Andrew A Ude
- Department of Kinesiology & Health, Rutgers University, New Brunswick, New Jersey
| | - Brandon L Alderman
- Department of Kinesiology & Health, Rutgers University, New Brunswick, New Jersey
- Center of Alcohol and Substance Use Studies, Rutgers University, New Brunswick, New Jersey
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2
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McNay EC, Pearson-Leary J. GluT4: A central player in hippocampal memory and brain insulin resistance. Exp Neurol 2020; 323:113076. [PMID: 31614121 PMCID: PMC6936336 DOI: 10.1016/j.expneurol.2019.113076] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 09/19/2019] [Accepted: 10/01/2019] [Indexed: 12/24/2022]
Abstract
Insulin is now well-established as playing multiple roles within the brain, and specifically as regulating hippocampal cognitive processes and metabolism. Impairments to insulin signaling, such as those seen in type 2 diabetes and Alzheimer's disease, are associated with brain hypometabolism and cognitive impairment, but the mechanisms of insulin's central effects are not determined. Several lines of research converge to suggest that the insulin-responsive glucose transporter GluT4 plays a central role in hippocampal memory processes, and that reduced activation of this transporter may underpin the cognitive impairments seen as a consequence of insulin resistance.
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Affiliation(s)
- Ewan C McNay
- Behavioral Neuroscience, University at Albany, Albany, NY, USA.
| | - Jiah Pearson-Leary
- Department of Anesthesiology, Abramson Research Center, Children's Hospital of Philadelphia, Philadelphia, PA, USA
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3
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Kumral D, Şansal F, Cesnaite E, Mahjoory K, Al E, Gaebler M, Nikulin VV, Villringer A. BOLD and EEG signal variability at rest differently relate to aging in the human brain. Neuroimage 2019; 207:116373. [PMID: 31759114 DOI: 10.1016/j.neuroimage.2019.116373] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 10/17/2019] [Accepted: 11/17/2019] [Indexed: 01/22/2023] Open
Abstract
Variability of neural activity is regarded as a crucial feature of healthy brain function, and several neuroimaging approaches have been employed to assess it noninvasively. Studies on the variability of both evoked brain response and spontaneous brain signals have shown remarkable changes with aging but it is unclear if the different measures of brain signal variability - identified with either hemodynamic or electrophysiological methods - reflect the same underlying physiology. In this study, we aimed to explore age differences of spontaneous brain signal variability with two different imaging modalities (EEG, fMRI) in healthy younger (25 ± 3 years, N = 135) and older (67 ± 4 years, N = 54) adults. Consistent with the previous studies, we found lower blood oxygenation level dependent (BOLD) variability in the older subjects as well as less signal variability in the amplitude of low-frequency oscillations (1-12 Hz), measured in source space. These age-related reductions were mostly observed in the areas that overlap with the default mode network. Moreover, age-related increases of variability in the amplitude of beta-band frequency EEG oscillations (15-25 Hz) were seen predominantly in temporal brain regions. There were significant sex differences in EEG signal variability in various brain regions while no significant sex differences were observed in BOLD signal variability. Bivariate and multivariate correlation analyses revealed no significant associations between EEG- and fMRI-based variability measures. In summary, we show that both BOLD and EEG signal variability reflect aging-related processes but are likely to be dominated by different physiological origins, which relate differentially to age and sex.
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Affiliation(s)
- D Kumral
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; MindBrainBody Institute at the Berlin School of Mind and Brain, Humboldt-Universität zu Berlin, Berlin, Germany.
| | - F Şansal
- International Graduate Program Medical Neurosciences, Charité-Universitätsmedizin, Berlin, Germany; Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - E Cesnaite
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - K Mahjoory
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; Institute for Biomagnetism and Biosignalanalysis, University of Muenster, Muenster, Germany
| | - E Al
- MindBrainBody Institute at the Berlin School of Mind and Brain, Humboldt-Universität zu Berlin, Berlin, Germany; Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - M Gaebler
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; MindBrainBody Institute at the Berlin School of Mind and Brain, Humboldt-Universität zu Berlin, Berlin, Germany
| | - V V Nikulin
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; Neurophysics Group, Department of Neurology, Campus Benjamin Franklin, Charité Universitätsmedizin Berlin, Berlin, Germany; Centre for Cognition and Decision Making, Institute for Cognitive Neuroscience, National Research University Higher School of Economics, Moscow, Russia
| | - A Villringer
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany; MindBrainBody Institute at the Berlin School of Mind and Brain, Humboldt-Universität zu Berlin, Berlin, Germany; Center for Stroke Research Berlin, Charité - Universitätsmedizin Berlin, Berlin, Germany; Department of Cognitive Neurology, University Hospital Leipzig, Leipzig, Germany
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4
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Williams VJ, Trombetta BA, Jafri RZ, Koenig AM, Wennick CD, Carlyle BC, Ekhlaspour L, Ahima RS, Russell SJ, Salat DH, Arnold SE. Task-related fMRI BOLD response to hyperinsulinemia in healthy older adults. JCI Insight 2019; 5:129700. [PMID: 31211691 DOI: 10.1172/jci.insight.129700] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND There is growing evidence to suggest that the brain is an important target for insulin action, and that states of insulin resistance may extend to the CNS with detrimental effects on cognitive functioning. Although the effect of systemic insulin resistance on peripheral organs is well-studied, the degree to which insulin impacts brain function in vivo remains unclear. METHODS This randomized, single-blinded, 2-way-crossover, sham-controlled, pilot study determined the effects of hyperinsulinemia on fMRI brain activation during a 2-back working memory task in 9 healthy older adults (aged 57-79 years). Each participant underwent two clamp procedures (an insulin infusion and a saline placebo infusion, with normoglycemia maintained during both conditions), to examine the effects of hyperinsulinemia on task performance and associated blood-oxygen-level dependent (BOLD) signal using fMRI. RESULTS Hyperinsulinemia (compared to saline control) was associated with an increase in both the spatial extent and relative strength of task-related BOLD signal during the 2-back task. Further, the degree of increased task-related activation in select brain regions correlated with greater systemic insulin sensitivity, as well as decreased reaction times and performance accuracy between experimental conditions. CONCLUSION Together, these findings provide evidence of insulin action in the CNS among older adults during periods of sustained cognitive demand, with the greatest effects noted for individuals with highest systemic insulin sensitivity. FUNDING This work was funded by the National Institutes of Health (5R21AG051958, 2016).
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Affiliation(s)
- Victoria J Williams
- Department of Neurology, Alzheimer's Clinical and Translational Research Unit, Massachusetts General Hospital, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA
| | - Bianca A Trombetta
- Department of Neurology, Alzheimer's Clinical and Translational Research Unit, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Rabab Z Jafri
- Diabetes Research Center and Pediatric Endocrine Unit and.,Diabetes Unit and Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Aaron M Koenig
- Department of Neurology, Alzheimer's Clinical and Translational Research Unit, Massachusetts General Hospital, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA
| | - Chase D Wennick
- Department of Neurology, Alzheimer's Clinical and Translational Research Unit, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Becky C Carlyle
- Department of Neurology, Alzheimer's Clinical and Translational Research Unit, Massachusetts General Hospital, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA
| | - Laya Ekhlaspour
- Diabetes Research Center and Pediatric Endocrine Unit and.,Diabetes Unit and Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Rexford S Ahima
- Division of Endocrinology, Diabetes and Metabolism, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
| | - Steven J Russell
- Diabetes Research Center and Pediatric Endocrine Unit and.,Diabetes Unit and Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - David H Salat
- Brain Aging and Dementia Laboratory, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts, USA.,Neuroimaging Research for Veterans Center, VA Boston Healthcare System, Boston, Massachusetts, USA
| | - Steven E Arnold
- Department of Neurology, Alzheimer's Clinical and Translational Research Unit, Massachusetts General Hospital, Boston, Massachusetts, USA.,Harvard Medical School, Boston, Massachusetts, USA
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Jones N, Riby LM, Smith MA. Glucose regulation and face recognition deficits in older adults: the role of attention. NEUROPSYCHOLOGY, DEVELOPMENT, AND COGNITION. SECTION B, AGING, NEUROPSYCHOLOGY AND COGNITION 2018; 25:673-694. [PMID: 28805109 DOI: 10.1080/13825585.2017.1365813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The present study investigated the perceptual, attentional, and memory processes underlying face recognition deficits observed in older adults with impaired glucoregulation. Participants were categorized as good glucoregulators or poor glucoregulators on the basis of an oral glucose tolerance test. Using event-related potential (ERP) methodology, 23 participants (62-88 years) performed a 2-stimulus oddball task. Participants were asked to rate and memorize 10 "target" faces, which were then presented amongst 120 unfamiliar foils. Behavioral results indicated that good glucoregulators were significantly more accurate at recognizing target faces. ERP markers of early visual perception (P1 and N170 components) and memory formation (P3 component) were unaffected by glucoregulatory efficiency. The P2 component, an index of attentional processing, was larger and delayed in the poor glucoregulators. To the best of our knowledge, this study is the first to suggest that face recognition deficits in poor glucoregulators may be due to impairments in attentional processing.
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Affiliation(s)
- Nicola Jones
- a Department of Psychology , Northumbria University , Newcastle upon Tyne , UK
- b Department of Psychology, Faculty of Science , Liverpool Hope University , Liverpool , UK
| | - Leigh M Riby
- a Department of Psychology , Northumbria University , Newcastle upon Tyne , UK
| | - Michael A Smith
- a Department of Psychology , Northumbria University , Newcastle upon Tyne , UK
- c Faculty of Health and Medical Sciences , University of Western Australia , Perth , Australia
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Kullmann S, Heni M, Hallschmid M, Fritsche A, Preissl H, Häring HU. Brain Insulin Resistance at the Crossroads of Metabolic and Cognitive Disorders in Humans. Physiol Rev 2016; 96:1169-209. [PMID: 27489306 DOI: 10.1152/physrev.00032.2015] [Citation(s) in RCA: 352] [Impact Index Per Article: 44.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Ever since the brain was identified as an insulin-sensitive organ, evidence has rapidly accumulated that insulin action in the brain produces multiple behavioral and metabolic effects, influencing eating behavior, peripheral metabolism, and cognition. Disturbances in brain insulin action can be observed in obesity and type 2 diabetes (T2D), as well as in aging and dementia. Decreases in insulin sensitivity of central nervous pathways, i.e., brain insulin resistance, may therefore constitute a joint pathological feature of metabolic and cognitive dysfunctions. Modern neuroimaging methods have provided new means of probing brain insulin action, revealing the influence of insulin on both global and regional brain function. In this review, we highlight recent findings on brain insulin action in humans and its impact on metabolism and cognition. Furthermore, we elaborate on the most prominent factors associated with brain insulin resistance, i.e., obesity, T2D, genes, maternal metabolism, normal aging, inflammation, and dementia, and on their roles regarding causes and consequences of brain insulin resistance. We also describe the beneficial effects of enhanced brain insulin signaling on human eating behavior and cognition and discuss potential applications in the treatment of metabolic and cognitive disorders.
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Affiliation(s)
- Stephanie Kullmann
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany; German Center for Diabetes Research (DZD e.V.), Tübingen, Germany; Department of Internal Medicine IV, University of Tübingen, Tübingen, Germany; Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany; and Department of Pharmacy and Biochemistry, Faculty of Science, Eberhard Karls Universität Tübingen, Tübingen, Germany
| | - Martin Heni
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany; German Center for Diabetes Research (DZD e.V.), Tübingen, Germany; Department of Internal Medicine IV, University of Tübingen, Tübingen, Germany; Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany; and Department of Pharmacy and Biochemistry, Faculty of Science, Eberhard Karls Universität Tübingen, Tübingen, Germany
| | - Manfred Hallschmid
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany; German Center for Diabetes Research (DZD e.V.), Tübingen, Germany; Department of Internal Medicine IV, University of Tübingen, Tübingen, Germany; Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany; and Department of Pharmacy and Biochemistry, Faculty of Science, Eberhard Karls Universität Tübingen, Tübingen, Germany
| | - Andreas Fritsche
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany; German Center for Diabetes Research (DZD e.V.), Tübingen, Germany; Department of Internal Medicine IV, University of Tübingen, Tübingen, Germany; Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany; and Department of Pharmacy and Biochemistry, Faculty of Science, Eberhard Karls Universität Tübingen, Tübingen, Germany
| | - Hubert Preissl
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany; German Center for Diabetes Research (DZD e.V.), Tübingen, Germany; Department of Internal Medicine IV, University of Tübingen, Tübingen, Germany; Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany; and Department of Pharmacy and Biochemistry, Faculty of Science, Eberhard Karls Universität Tübingen, Tübingen, Germany
| | - Hans-Ulrich Häring
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany; German Center for Diabetes Research (DZD e.V.), Tübingen, Germany; Department of Internal Medicine IV, University of Tübingen, Tübingen, Germany; Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany; and Department of Pharmacy and Biochemistry, Faculty of Science, Eberhard Karls Universität Tübingen, Tübingen, Germany
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7
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Hege MA, Kullmann S, Heni M, Schleger F, Linder K, Fritsche A, Preissl H. Electro/magnetoencephalographic signatures of human brain insulin resistance. Curr Opin Behav Sci 2016. [DOI: 10.1016/j.cobeha.2016.05.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Heni M, Kullmann S, Preissl H, Fritsche A, Häring HU. Impaired insulin action in the human brain: causes and metabolic consequences. Nat Rev Endocrinol 2015; 11:701-11. [PMID: 26460339 DOI: 10.1038/nrendo.2015.173] [Citation(s) in RCA: 179] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Over the past few years, evidence has accumulated that the human brain is an insulin-sensitive organ. Insulin regulates activity in a limited number of specific brain areas that are important for memory, reward, eating behaviour and the regulation of whole-body metabolism. Accordingly, insulin in the brain modulates cognition, food intake and body weight as well as whole-body glucose, energy and lipid metabolism. However, brain imaging studies have revealed that not everybody responds equally to insulin and that a substantial number of people are brain insulin resistant. In this Review, we provide an overview of the effects of insulin in the brain in humans and the relevance of the effects for physiology. We present emerging evidence for insulin resistance of the human brain. Factors associated with brain insulin resistance such as obesity and increasing age, as well as possible pathogenic factors such as visceral fat, saturated fatty acids, alterations at the blood-brain barrier and certain genetic polymorphisms, are reviewed. In particular, the metabolic consequences of brain insulin resistance are discussed and possible future approaches to overcome brain insulin resistance and thereby prevent or treat obesity and type 2 diabetes mellitus are outlined.
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Affiliation(s)
- Martin Heni
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Eberhard Karls University, Partners in the German Centre for Diabetes Research (DZD), Otfried-Müller-Street 10, 72076 Tübingen, Germany
| | - Stephanie Kullmann
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Centre Munich at the University of Tübingen, Partners in the German Centre for Diabetes Research (DZD), Otfried-Müller-Street 10, 72076 Tübingen, Germany
| | - Hubert Preissl
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Centre Munich at the University of Tübingen, Partners in the German Centre for Diabetes Research (DZD), Otfried-Müller-Street 10, 72076 Tübingen, Germany
| | - Andreas Fritsche
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Eberhard Karls University, Partners in the German Centre for Diabetes Research (DZD), Otfried-Müller-Street 10, 72076 Tübingen, Germany
| | - Hans-Ulrich Häring
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Angiology, Nephrology and Clinical Chemistry, Eberhard Karls University, Partners in the German Centre for Diabetes Research (DZD), Otfried-Müller-Street 10, 72076 Tübingen, Germany
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9
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Sartorius T, Peter A, Heni M, Maetzler W, Fritsche A, Häring HU, Hennige AM. The brain response to peripheral insulin declines with age: a contribution of the blood-brain barrier? PLoS One 2015; 10:e0126804. [PMID: 25965336 PMCID: PMC4429020 DOI: 10.1371/journal.pone.0126804] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 04/07/2015] [Indexed: 01/26/2023] Open
Abstract
Objectives It is a matter of debate whether impaired insulin action originates from a defect at the neural level or impaired transport of the hormone into the brain. In this study, we aimed to investigate the effect of aging on insulin concentrations in the periphery and the central nervous system as well as its impact on insulin-dependent brain activity. Methods Insulin, glucose and albumin concentrations were determined in 160 paired human serum and cerebrospinal fluid (CSF) samples. Additionally, insulin was applied in young and aged mice by subcutaneous injection or intracerebroventricularly to circumvent the blood-brain barrier. Insulin action and cortical activity were assessed by Western blotting and electrocorticography radiotelemetric measurements. Results In humans, CSF glucose and insulin concentrations were tightly correlated with the respective serum/plasma concentrations. The CSF/serum ratio for insulin was reduced in older subjects while the CSF/serum ratio for albumin increased with age like for most other proteins. Western blot analysis in murine whole brain lysates revealed impaired phosphorylation of AKT (P-AKT) in aged mice following peripheral insulin stimulation whereas P-AKT was comparable to levels in young mice after intracerebroventricular insulin application. As readout for insulin action in the brain, insulin-mediated cortical brain activity instantly increased in young mice subcutaneously injected with insulin but was significantly reduced and delayed in aged mice during the treatment period. When insulin was applied intracerebroventricularly into aged animals, brain activity was readily improved. Conclusions This study discloses age-dependent changes in insulin CSF/serum ratios in humans. In the elderly, cerebral insulin resistance might be partially attributed to an impaired transport of insulin into the central nervous system.
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Affiliation(s)
- Tina Sartorius
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry, University of Tuebingen, Tuebingen, Germany
- German Center for Diabetes Research (DZD), Tuebingen, Germany
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tuebingen (IDM), Tuebingen, Germany
- * E-mail:
| | - Andreas Peter
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry, University of Tuebingen, Tuebingen, Germany
- German Center for Diabetes Research (DZD), Tuebingen, Germany
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tuebingen (IDM), Tuebingen, Germany
| | - Martin Heni
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry, University of Tuebingen, Tuebingen, Germany
- German Center for Diabetes Research (DZD), Tuebingen, Germany
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tuebingen (IDM), Tuebingen, Germany
| | - Walter Maetzler
- Department of Neurodegenerative Diseases and Hertie Institute for Clinical Brain Research, University of Tuebingen, Tuebingen, Germany
- German Center for Neurodegenerative Diseases (DZNE), Tuebingen, Germany
| | - Andreas Fritsche
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry, University of Tuebingen, Tuebingen, Germany
- German Center for Diabetes Research (DZD), Tuebingen, Germany
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tuebingen (IDM), Tuebingen, Germany
| | - Hans-Ulrich Häring
- Department of Internal Medicine, Division of Endocrinology, Diabetology, Vascular Disease, Nephrology and Clinical Chemistry, University of Tuebingen, Tuebingen, Germany
- German Center for Diabetes Research (DZD), Tuebingen, Germany
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tuebingen (IDM), Tuebingen, Germany
| | - Anita M. Hennige
- German Center for Diabetes Research (DZD), Tuebingen, Germany
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tuebingen (IDM), Tuebingen, Germany
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Marder TJ, Flores VL, Bolo NR, Hoogenboom WS, Simonson DC, Jacobson AM, Foote SE, Shenton ME, Sperling RA, Musen G. Task-induced brain activity patterns in type 2 diabetes: a potential biomarker for cognitive decline. Diabetes 2014; 63:3112-9. [PMID: 24705405 PMCID: PMC4141362 DOI: 10.2337/db13-1783] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Patients with type 2 diabetes demonstrate reduced functional connectivity within the resting state default mode network (DMN), which may signal heightened risk for cognitive decline. In other populations at risk for cognitive decline, additional magnetic resonance imaging abnormalities are evident during task performance, including impaired deactivation of the DMN and reduced activation of task-relevant regions. We investigated whether middle-aged type 2 diabetic patients show these brain activity patterns during encoding and recognition tasks. Compared with control participants, we observed both reduced 1) activation of the dorsolateral prefrontal cortex during encoding and 2) deactivation of the DMN during recognition in type 2 diabetic patients, despite normal cognition. During recognition, activation in several task-relevant regions, including the dorsolateral prefrontal cortex and DMN regions, was positively correlated with HbA1c and insulin resistance, suggesting that these important markers of glucose metabolism impact the brain's response to a cognitive challenge. Plasma glucose ≥11 mmol/L was associated with impaired deactivation of the DMN, suggesting that acute hyperglycemia contributes to brain abnormalities. Since elderly type 2 diabetic patients often demonstrate cognitive impairments, it is possible that these task-induced brain activity patterns observed in middle age may signal impending cognitive decline.
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Affiliation(s)
- Thomas J Marder
- Clinical, Behavioral and Outcomes Research, Joslin Diabetes Center, Boston, MA
| | - Veronica L Flores
- Clinical, Behavioral and Outcomes Research, Joslin Diabetes Center, Boston, MA Department of Psychology, Brandeis University, Waltham, MA
| | - Nicolas R Bolo
- Department of Psychiatry, Beth Israel Deaconess Medical Center, Boston, MA Harvard Medical School, Boston, MA
| | - Wouter S Hoogenboom
- Clinical, Behavioral and Outcomes Research, Joslin Diabetes Center, Boston, MA Psychiatry Neuroimaging Laboratory, Department of Psychiatry, Brigham and Women's Hospital, Boston, MA Albert Einstein College of Medicine, Yeshiva University, Bronx, NY
| | - Donald C Simonson
- Harvard Medical School, Boston, MA Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, Brigham and Women's Hospital, Boston, MA
| | - Alan M Jacobson
- Clinical, Behavioral and Outcomes Research, Joslin Diabetes Center, Boston, MA Harvard Medical School, Boston, MA Research Institute, Winthrop-University Hospital, Mineola, NY
| | - Sarah E Foote
- Clinical, Behavioral and Outcomes Research, Joslin Diabetes Center, Boston, MA Tulane University School of Medicine, Tulane University, New Orleans, LA
| | - Martha E Shenton
- Harvard Medical School, Boston, MA Psychiatry Neuroimaging Laboratory, Department of Psychiatry, Brigham and Women's Hospital, Boston, MA Clinical Neuroscience Division, Laboratory of Neuroscience, Department of Psychiatry, Veterans Affairs Boston Healthcare System, Brockton Division, Brockton, MA
| | - Reisa A Sperling
- Harvard Medical School, Boston, MA Department of Neurology, Massachusetts General Hospital, Boston, MA Department of Neurology, Brigham and Women's Hospital, Boston, MA Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA
| | - Gail Musen
- Clinical, Behavioral and Outcomes Research, Joslin Diabetes Center, Boston, MA Harvard Medical School, Boston, MA
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Schilling TM, Ferreira de Sá DS, Westerhausen R, Strelzyk F, Larra MF, Hallschmid M, Savaskan E, Oitzl MS, Busch HP, Naumann E, Schächinger H. Intranasal insulin increases regional cerebral blood flow in the insular cortex in men independently of cortisol manipulation. Hum Brain Mapp 2013; 35:1944-56. [PMID: 23907764 DOI: 10.1002/hbm.22304] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Revised: 02/22/2013] [Accepted: 03/18/2013] [Indexed: 01/09/2023] Open
Abstract
Insulin and cortisol play a key role in the regulation of energy homeostasis, appetite, and satiety. Little is known about the action and interaction of both hormones in brain structures controlling food intake and the processing of neurovisceral signals from the gastrointestinal tract. In this study, we assessed the impact of single and combined application of insulin and cortisol on resting regional cerebral blood flow (rCBF) in the insular cortex. After standardized periods of food restriction, 48 male volunteers were randomly assigned to receive either 40 IU intranasal insulin, 30 mg oral cortisol, both, or neither (placebo). Continuous arterial spin labeling (CASL) sequences were acquired before and after pharmacological treatment. We observed a bilateral, locally distinct rCBF increase after insulin administration in the insular cortex and the putamen. Insulin effects on rCBF were present regardless of whether participants had received cortisol or not. Our results indicate that insulin, but not cortisol, affects blood flow in human brain structures involved in the regulation of eating behavior.
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Affiliation(s)
- Thomas M Schilling
- Institute of Psychobiology, Division of Clinical Psychophysiology, University of Trier, Trier, Germany
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12
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Calderone DJ, Martinez A, Zemon V, Hoptman MJ, Hu G, Watkins JE, Javitt DC, Butler PD. Comparison of psychophysical, electrophysiological, and fMRI assessment of visual contrast responses in patients with schizophrenia. Neuroimage 2013; 67:153-62. [PMID: 23194815 PMCID: PMC3544989 DOI: 10.1016/j.neuroimage.2012.11.019] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2012] [Revised: 11/12/2012] [Accepted: 11/18/2012] [Indexed: 11/24/2022] Open
Abstract
Perception has been identified by the NIMH-sponsored Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia (CNTRICS) group as a useful domain for assessing cognitive deficits in patients with schizophrenia. Specific measures of contrast gain derived from recordings of steady-state visual evoked potentials (ssVEP) have demonstrated neural deficits within the visual pathways of patients with schizophrenia. Psychophysical measures of contrast sensitivity have also shown functional loss in these patients. In the current study, functional magnetic resonance imaging (fMRI) was used in conjunction with ssVEP and contrast sensitivity testing to elucidate the neural underpinnings of these deficits. During fMRI scanning, participants viewed 1) the same low and higher spatial frequency stimuli used in the psychophysical contrast sensitivity task, at both individual detection threshold contrast and at a high contrast; and 2) the same stimuli used in the ssVEP paradigm, which were designed to be biased toward either the magnocellular or parvocellular visual pathway. Patients showed significant impairment in contrast sensitivity at both spatial frequencies in the psychophysical task, but showed reduced occipital activation volume for low, but not higher, spatial frequency at the low and high contrasts tested in the magnet. As expected, patients exhibited selective deficits under the magnocellular-biased ssVEP condition. However, occipital lobe fMRI responses demonstrated the same general pattern for magnocellular- and parvocellular-biased stimuli across groups. These results indicate dissociation between the fMRI measures and the psychophysical/ssVEP measures. These latter measures appear to have greater value for the functional assessment of the contrast deficits explored here.
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Affiliation(s)
- Daniel J Calderone
- Nathan S. Kline Institute for Psychiatric Research, 140 Old Orangeburg Road, Orangeburg, NY 10962, USA.
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13
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Abstract
Functional neuroimaging techniques can be used to study changes in regional brain activation, using changes in surrogate markers such as regional cerebral perfusion and rates of glucose uptake or metabolism. These approaches are shedding new light on two major health problems: the increasing burden of type 2 diabetes mellitus (T2DM), which is driven by the rising prevalence of insulin resistance and obesity; and recurrent intractable problematic hypoglycaemia, which is driven by the cognitive impairment that can occur in association with iatrogenic hypoglycaemic episodes. Some patients with diabetes mellitus lose awareness of being hypoglycaemic, which puts them at risk of severe hypoglycaemia as they are unlikely to take action to prevent the condition worsening. Involvement of corticolimbic brain and centres serving higher executive functions as well as the hypothalamus has been demonstrated in both situations and has implications for therapy. This Review describes the relevant principles of functional neuroimaging techniques and presents data supporting the notion that the dysregulation of central pathways involved in metabolic regulation, reward and appetite could contribute to problematic hypoglycaemia during therapy for diabetes mellitus and to insulin-resistant obesity and T2DM. Understanding these dysregulations could enable the development of novel clinical interventions.
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Affiliation(s)
- Yee-Seun Cheah
- Diabetes Research Group, Weston Education Centre, Denmark Hill Campus, King's College London, 10 Cutcombe Road, London SE5 9RJ, UK
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14
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Guthoff M, Stingl KT, Tschritter O, Rogic M, Heni M, Stingl K, Hallschmid M, Häring HU, Fritsche A, Preissl H, Hennige AM. The insulin-mediated modulation of visually evoked magnetic fields is reduced in obese subjects. PLoS One 2011; 6:e19482. [PMID: 21589921 PMCID: PMC3092755 DOI: 10.1371/journal.pone.0019482] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2010] [Accepted: 04/08/2011] [Indexed: 01/22/2023] Open
Abstract
Background Insulin is an anorexigenic hormone that contributes to the termination of food intake in the postprandial state. An alteration in insulin action in the brain, named “cerebral insulin resistance”, is responsible for overeating and the development of obesity. Methodology/Principal Findings To analyze the direct effect of insulin on food-related neuronal activity we tested 10 lean and 10 obese subjects. We conducted a magnetencephalography study during a visual working memory task in both the basal state and after applying insulin or placebo spray intranasally to bypass the blood brain barrier. Food and non-food pictures were presented and subjects had to determine whether or not two consecutive pictures belonged to the same category. Intranasal insulin displayed no effect on blood glucose, insulin or C-peptide concentrations in the periphery; however, it led to an increase in the components of evoked fields related to identification and categorization of pictures (at around 170 ms post stimuli in the visual ventral stream) in lean subjects when food pictures were presented. In contrast, insulin did not modulate food-related brain activity in obese subjects. Conclusions/Significance We demonstrated that intranasal insulin increases the cerebral processing of food pictures in lean whereas this was absent in obese subjects. This study further substantiates the presence of a “cerebral insulin resistance” in obese subjects and might be relevant in the pathogenesis of obesity.
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Affiliation(s)
- Martina Guthoff
- Internal Medicine IV, Department of Endocrinology and Diabetes, Angiology, Nephrology and Clinical Chemistry, University Hospital, University of Tübingen, Tübingen, Germany
| | | | - Otto Tschritter
- Internal Medicine IV, Department of Endocrinology and Diabetes, Angiology, Nephrology and Clinical Chemistry, University Hospital, University of Tübingen, Tübingen, Germany
| | - Maja Rogic
- MEG Center, University of Tübingen, Tübingen, Germany
| | - Martin Heni
- Internal Medicine IV, Department of Endocrinology and Diabetes, Angiology, Nephrology and Clinical Chemistry, University Hospital, University of Tübingen, Tübingen, Germany
| | - Katarina Stingl
- Center for Ophthalmology, University of Tübingen, Tübingen, Germany
| | | | - Hans-Ulrich Häring
- Internal Medicine IV, Department of Endocrinology and Diabetes, Angiology, Nephrology and Clinical Chemistry, University Hospital, University of Tübingen, Tübingen, Germany
| | - Andreas Fritsche
- Internal Medicine IV, Department of Endocrinology and Diabetes, Angiology, Nephrology and Clinical Chemistry, University Hospital, University of Tübingen, Tübingen, Germany
- * E-mail:
| | - Hubert Preissl
- MEG Center, University of Tübingen, Tübingen, Germany
- Department for Obstetrics and Gynecology, Medical College, University of Arkansas, Little Rock, Arkansas, United States of America
| | - Anita M. Hennige
- Internal Medicine IV, Department of Endocrinology and Diabetes, Angiology, Nephrology and Clinical Chemistry, University Hospital, University of Tübingen, Tübingen, Germany
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15
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Brabant G, Cain J, Jackson A, Kreitschmann-Andermahr I. Visualizing hormone actions in the brain. Trends Endocrinol Metab 2011; 22:153-63. [PMID: 21497512 DOI: 10.1016/j.tem.2011.01.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Revised: 01/19/2011] [Accepted: 01/20/2011] [Indexed: 01/01/2023]
Abstract
Profound and multifaceted effects of hormones on the development, maturation and function of the CNS are well documented. Recent developments in magnetic resonance imagining (MRI) and positron emission tomography (PET) permit detailed in vivo studies of cerebral structure and function in humans. Techniques to measure subtle differences in cerebral structure, regional brain activation, changes in blood flow and other physiological biomarkers allow us to translate experimental evidence of hormone effects obtained from animal models to humans. Here we review the imaging techniques available to support studies of hormone effects on the CNS, emphasizing the recent developments of MRI. In summarizing the major current studies we discuss the potential of these techniques for an emerging new field in endocrinology.
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Affiliation(s)
- Georg Brabant
- Department of Endocrinology, The Christie, Manchester Academic Health Science Centre, Wilmslow Road, Manchester M20 4BX, UK.
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16
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Grichisch Y, Çavuşoğlu M, Preissl H, Uludağ K, Hallschmid M, Birbaumer N, Häring HU, Fritsche A, Veit R. Differential effects of intranasal insulin and caffeine on cerebral blood flow. Hum Brain Mapp 2011; 33:280-7. [PMID: 21391271 DOI: 10.1002/hbm.21216] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Accepted: 10/26/2010] [Indexed: 01/22/2023] Open
Abstract
Insulin is an important modulator of brain functions such as memory and appetite regulation. Besides the effect on neuronal activity, it is also possible that insulin has a direct vasodilatory effect on cerebral blood flow (CBF). We investigated the impact of increased insulin levels in the central nervous system on basal and task-induced CBF as well as blood oxygenation level-dependent (BOLD) response in the visual cortex using pulsed arterial spin-labeling MRI. An intranasal insulin application was used to avoid peripheral hyperinsulinaemia, which would lead to a cascade of hormonal changes. In a control experiment, caffeine was applied due to its well-known impact on the vasculature of the brain leading to a reliable reduction of CBF. Eight lean subjects were included in the study. On 2 separate days, intranasal human insulin or caffeine tablets were given to the subjects after fasting over night. On each day, basal CBF and task-induced CBF were measured before and 30 min after application of insulin or caffeine in each subject. During the task condition, a flickering checkerboard was presented. Insulin had no effect on basal CBF and task-induced CBF in comparison with drug-free baseline measurement in the visual cortex and control regions. After caffeine application, however, there was a significant decrease of CBF during stimulation in the visual cortex. The BOLD response was not altered by insulin or caffeine between pre- and postdose measurements. In conclusion, we found no evidence for a direct vasodilatory effect of intranasal insulin on the cerebral vascular system in this study.
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Affiliation(s)
- Yuko Grichisch
- Department of Internal Medicine IV, University Hospital, Tübingen, Germany
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Page KA, Arora J, Qiu M, Relwani R, Constable RT, Sherwin RS. Small decrements in systemic glucose provoke increases in hypothalamic blood flow prior to the release of counterregulatory hormones. Diabetes 2009; 58:448-52. [PMID: 19017765 PMCID: PMC2628619 DOI: 10.2337/db08-1224] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE The hypothalamus is the central brain region responsible for sensing and integrating responses to changes in circulating glucose. The aim of this study was to determine the time sequence relationship between hypothalamic activation and the initiation of the counterregulatory hormonal response to small decrements in systemic glucose. RESEARCH DESIGN AND METHODS Nine nondiabetic volunteers underwent two hyperinsulinemic clamp sessions in which pulsed arterial spin labeling was used to measure regional cerebral blood flow (CBF) at euglycemia ( approximately 95 mg/dl) on one occasion and as glucose levels were declining to a nadir of approximately 50 mg/dl on another occasion. Plasma glucose and counterregulatory hormones were measured during both study sessions. RESULTS CBF to the hypothalamus significantly increased when glucose levels decreased to 77.2 +/- 2 mg/dl compared with the euglycemic control session when glucose levels were 95.7 +/- 3 mg/dl (P = 0.0009). Hypothalamic perfusion was significantly increased before there was a significant elevation in counterregulatory hormones. CONCLUSIONS Our data suggest that the hypothalamus is exquisitely sensitive to small decrements in systemic glucose levels in healthy, nondiabetic subjects and that hypothalamic blood flow, and presumably neuronal activity, precedes the rise in counterregulatory hormones seen during hypoglycemia.
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Affiliation(s)
- Kathleen A Page
- Department of Internal Medicine, Division of Endocrinology, Yale University School of Medicine, New Haven, Connecticut, USA.
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18
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Insulin and ghrelin: peripheral hormones modulating memory and hippocampal function. Curr Opin Pharmacol 2007; 7:628-32. [PMID: 18023257 DOI: 10.1016/j.coph.2007.10.009] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2007] [Accepted: 10/13/2007] [Indexed: 11/20/2022]
Abstract
Peptide hormones, initially identified in the periphery and best known for regulation of food intake and appetite, have increasingly been shown to regulate brain functions not only within the hypothalamus but elsewhere. The hippocampus, in particular, expresses receptors for many hormones. Both insulin and ghrelin are now known to enhance hippocampal memory processes; in addition, insulin acts to increase local hippocampal metabolism and regulate synaptic plasticity, while administration of ghrelin has been shown to promote dendritic spine synaptic formation and to increase anxiety. While insulin's effects appear to be specifically within the hippocampus, ghrelin may act at a range of sites within the limbic system.
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Sotero RC, Trujillo-Barreto NJ. Biophysical model for integrating neuronal activity, EEG, fMRI and metabolism. Neuroimage 2007; 39:290-309. [PMID: 17919931 DOI: 10.1016/j.neuroimage.2007.08.001] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2007] [Revised: 07/19/2007] [Accepted: 08/06/2007] [Indexed: 11/30/2022] Open
Abstract
Our goal is to model the coupling between neuronal activity, cerebral metabolic rates of glucose and oxygen consumption, cerebral blood flow (CBF), electroencephalography (EEG) and blood oxygenation level-dependent (BOLD) responses. In order to accomplish this, two previous models are coupled: a metabolic/hemodynamic model (MHM) for a voxel, linking BOLD signals and neuronal activity, and a neural mass model describing the neuronal dynamics within a voxel and its interactions with voxels of the same area (short-range interactions) and other areas (long-range interactions). For coupling both models, we take as the input to the BOLD model, the number of active synapses within the voxel, that is, the average number of synapses that will receive an action potential within the time unit. This is obtained by considering the action potentials transmitted between neuronal populations within the voxel, as well as those arriving from other voxels. Simulations are carried out for testing the integrated model. Results show that realistic evoked potentials (EP) at electrodes on the scalp surface and the corresponding BOLD signals for each voxel are produced by the model. In another simulation, the alpha rhythm was reproduced and reasonable similarities with experimental data were obtained when calculating correlations between BOLD signals and the alpha power curve. The origin of negative BOLD responses and the characteristics of EEG, PET and BOLD signals in Alzheimer's disease were also studied.
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Affiliation(s)
- Roberto C Sotero
- Brain Dynamics Department, Cuban Neuroscience Center, Avenue 25, Esq 158, #15202, PO Box 6412, 6414, Cubanacán, Playa, Havana, Cuba.
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