1
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Granholm AC, Hamlett ED. The Role of Tau Pathology in Alzheimer's Disease and Down Syndrome. J Clin Med 2024; 13:1338. [PMID: 38592182 PMCID: PMC10932364 DOI: 10.3390/jcm13051338] [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: 01/24/2024] [Revised: 02/10/2024] [Accepted: 02/20/2024] [Indexed: 04/10/2024] Open
Abstract
Background: Individuals with Down syndrome (DS) exhibit an almost complete penetrance of Alzheimer's disease (AD) pathology but are underrepresented in clinical trials for AD. The Tau protein is associated with microtubule function in the neuron and is crucial for normal axonal transport. In several different neurodegenerative disorders, Tau misfolding leads to hyper-phosphorylation of Tau (p-Tau), which may seed pathology to bystander cells and spread. This review is focused on current findings regarding p-Tau and its potential to seed pathology as a "prion-like" spreader. It also considers the consequences of p-Tau pathology leading to AD, particularly in individuals with Down syndrome. Methods: Scopus (SC) and PubMed (PM) were searched in English using keywords "tau AND seeding AND brain AND down syndrome". A total of 558 SC or 529 PM potentially relevant articles were identified, of which only six SC or three PM articles mentioned Down syndrome. This review was built upon the literature and the recent findings of our group and others. Results: Misfolded p-Tau isoforms are seeding competent and may be responsible for spreading AD pathology. Conclusions: This review demonstrates recent work focused on understanding the role of neurofibrillary tangles and monomeric/oligomeric Tau in the prion-like spreading of Tau pathology in the human brain.
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Affiliation(s)
- Ann-Charlotte Granholm
- Department of Neurosurgery, University of Colorado Anschutz Medical Center, Aurora, CO 80045, USA
| | - Eric D. Hamlett
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC 29425, USA;
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2
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Weber LM, Divecha HR, Tran MN, Kwon SH, Spangler A, Montgomery KD, Tippani M, Bharadwaj R, Kleinman JE, Page SC, Hyde TM, Collado-Torres L, Maynard KR, Martinowich K, Hicks SC. The gene expression landscape of the human locus coeruleus revealed by single-nucleus and spatially-resolved transcriptomics. eLife 2024; 12:RP84628. [PMID: 38266073 PMCID: PMC10945708 DOI: 10.7554/elife.84628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2024] Open
Abstract
Norepinephrine (NE) neurons in the locus coeruleus (LC) make long-range projections throughout the central nervous system, playing critical roles in arousal and mood, as well as various components of cognition including attention, learning, and memory. The LC-NE system is also implicated in multiple neurological and neuropsychiatric disorders. Importantly, LC-NE neurons are highly sensitive to degeneration in both Alzheimer's and Parkinson's disease. Despite the clinical importance of the brain region and the prominent role of LC-NE neurons in a variety of brain and behavioral functions, a detailed molecular characterization of the LC is lacking. Here, we used a combination of spatially-resolved transcriptomics and single-nucleus RNA-sequencing to characterize the molecular landscape of the LC region and the transcriptomic profile of LC-NE neurons in the human brain. We provide a freely accessible resource of these data in web-accessible and downloadable formats.
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Affiliation(s)
- Lukas M Weber
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public HealthBaltimoreUnited States
| | - Heena R Divecha
- Lieber Institute for Brain Development, Johns Hopkins Medical CampusBaltimoreUnited States
| | - Matthew N Tran
- Lieber Institute for Brain Development, Johns Hopkins Medical CampusBaltimoreUnited States
| | - Sang Ho Kwon
- Lieber Institute for Brain Development, Johns Hopkins Medical CampusBaltimoreUnited States
- Department of Neuroscience, Johns Hopkins School of MedicineBaltimoreUnited States
| | - Abby Spangler
- Lieber Institute for Brain Development, Johns Hopkins Medical CampusBaltimoreUnited States
| | - Kelsey D Montgomery
- Lieber Institute for Brain Development, Johns Hopkins Medical CampusBaltimoreUnited States
| | - Madhavi Tippani
- Lieber Institute for Brain Development, Johns Hopkins Medical CampusBaltimoreUnited States
| | - Rahul Bharadwaj
- Lieber Institute for Brain Development, Johns Hopkins Medical CampusBaltimoreUnited States
| | - Joel E Kleinman
- Lieber Institute for Brain Development, Johns Hopkins Medical CampusBaltimoreUnited States
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins School of MedicineBaltimoreUnited States
| | - Stephanie C Page
- Lieber Institute for Brain Development, Johns Hopkins Medical CampusBaltimoreUnited States
| | - Thomas M Hyde
- Lieber Institute for Brain Development, Johns Hopkins Medical CampusBaltimoreUnited States
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins School of MedicineBaltimoreUnited States
- Department of Neurology, Johns Hopkins School of MedicineBaltimoreUnited States
| | | | - Kristen R Maynard
- Lieber Institute for Brain Development, Johns Hopkins Medical CampusBaltimoreUnited States
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins School of MedicineBaltimoreUnited States
| | - Keri Martinowich
- Lieber Institute for Brain Development, Johns Hopkins Medical CampusBaltimoreUnited States
- Department of Neuroscience, Johns Hopkins School of MedicineBaltimoreUnited States
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins School of MedicineBaltimoreUnited States
- The Kavli Neuroscience Discovery Institute, Johns Hopkins UniversityBaltimoreUnited States
| | - Stephanie C Hicks
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public HealthBaltimoreUnited States
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3
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Matt RA, Martin RS, Evans AK, Gever JR, Vargas GA, Shamloo M, Ford AP. Locus Coeruleus and Noradrenergic Pharmacology in Neurodegenerative Disease. Handb Exp Pharmacol 2024; 285:555-616. [PMID: 37495851 DOI: 10.1007/164_2023_677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/28/2023]
Abstract
Adrenoceptors (ARs) throughout the brain are stimulated by noradrenaline originating mostly from neurons of the locus coeruleus, a brainstem nucleus that is ostensibly the earliest to show detectable pathology in neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. The α1-AR, α2-AR, and β-AR subtypes expressed in target brain regions and on a range of cell populations define the physiological responses to noradrenaline, which includes activation of cognitive function in addition to modulation of neurometabolism, cerebral blood flow, and neuroinflammation. As these heterocellular functions are critical for maintaining brain homeostasis and neuronal health, combating the loss of noradrenergic tone from locus coeruleus degeneration may therefore be an effective treatment for both cognitive symptoms and disease modification in neurodegenerative indications. Two pharmacologic approaches are receiving attention in recent clinical studies: preserving noradrenaline levels (e.g., via reuptake inhibition) and direct activation of target adrenoceptors. Here, we review the expression and role of adrenoceptors in the brain, the preclinical studies which demonstrate that adrenergic stimulation can support cognitive function and cerebral health by reversing the effects of noradrenaline depletion, and the human data provided by pharmacoepidemiologic analyses and clinical trials which together identify adrenoceptors as promising targets for the treatment of neurodegenerative disease.
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Affiliation(s)
| | | | - Andrew K Evans
- Department of Neurosurgery, Stanford University School of Medicine, Palo Alto, CA, USA
| | | | | | - Mehrdad Shamloo
- Department of Neurosurgery, Stanford University School of Medicine, Palo Alto, CA, USA
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4
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Bachman SL, Cole S, Yoo HJ, Nashiro K, Min J, Mercer N, Nasseri P, Thayer JF, Lehrer P, Mather M. Daily heart rate variability biofeedback training decreases locus coeruleus MRI contrast in younger adults in a randomized clinical trial. Int J Psychophysiol 2023; 193:112241. [PMID: 37647944 PMCID: PMC10591988 DOI: 10.1016/j.ijpsycho.2023.08.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 08/10/2023] [Accepted: 08/25/2023] [Indexed: 09/01/2023]
Abstract
As an arousal hub region in the brain, the locus coeruleus (LC) has bidirectional connections with the autonomic nervous system. Magnetic resonance imaging (MRI)-based measures of LC structural integrity have been linked to cognition and arousal, but less is known about factors that influence LC structure and function across time. Here, we tested the effects of heart rate variability (HRV) biofeedback, an intervention targeting the autonomic nervous system, on LC MRI contrast and sympathetic activity. Younger and older participants completed daily HRV biofeedback training for five weeks. Those assigned to an experimental condition performed biofeedback involving slow, paced breathing designed to increase heart rate oscillations, whereas those assigned to a control condition performed biofeedback to decrease heart rate oscillations. At the pre- and post-training timepoints, LC contrast was assessed using turbo spin echo MRI scans, and RNA sequencing was used to assess cAMP-responsive element binding protein (CREB)-regulated gene expression in circulating blood cells, an index of sympathetic nervous system signaling. We found that left LC contrast decreased in younger participants in the experimental group, and across younger participants, decreases in left LC contrast were related to the extent to which participants increased their heart rate oscillations during training. Furthermore, decreases in left LC contrast were associated with decreased expression of CREB-associated gene transcripts. On the contrary, there were no effects of biofeedback on LC contrast among older participants in the experimental group. These findings provide novel evidence that in younger adults, HRV biofeedback involving slow, paced breathing can decrease both LC contrast and sympathetic nervous system signaling.
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Affiliation(s)
- Shelby L Bachman
- University of Southern California, Los Angeles, CA 90089, United States of America
| | - Steve Cole
- University of California Los Angeles, Los Angeles, CA 90095, United States of America
| | - Hyun Joo Yoo
- University of Southern California, Los Angeles, CA 90089, United States of America
| | - Kaoru Nashiro
- University of Southern California, Los Angeles, CA 90089, United States of America
| | - Jungwon Min
- University of Southern California, Los Angeles, CA 90089, United States of America
| | - Noah Mercer
- University of Southern California, Los Angeles, CA 90089, United States of America
| | - Padideh Nasseri
- University of Southern California, Los Angeles, CA 90089, United States of America
| | - Julian F Thayer
- University of California Irvine, Irvine, CA 92697, United States of America
| | - Paul Lehrer
- Rutgers University, Piscataway, NJ 08852, United States of America
| | - Mara Mather
- University of Southern California, Los Angeles, CA 90089, United States of America.
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5
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Riley E, Cicero N, Swallow K, De Rosa E, Anderson A. Locus coeruleus neuromelanin accumulation and dissipation across the lifespan. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.17.562814. [PMID: 37905002 PMCID: PMC10614878 DOI: 10.1101/2023.10.17.562814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
The pigment neuromelanin, produced in the locus coeruleus (LC) as a byproduct of catecholamine synthesis, gives the "blue spot" its name, and both identifies LC neurons and is thought to play an important yet complex role in normal and pathological aging. Using neuromelanin-sensitive T1-weighted turbo spin echo MRI scans we characterized volume and neuromelanin signal intensity in the LC of 96 participants between the ages of 19 and 86. Although LC volume did not change significantly throughout the lifespan, LC neuromelanin signal intensity increased from early adulthood, peaked around age 60 and precipitously declined thereafter. Neuromelanin intensity was greater in the caudal relative to rostral extent and in women relative to men. With regard to function, rostral LC neuromelanin intensity was associated with fluid cognition in older adults (60+) only in those above the 50th percentile of cognitive ability for age. The gradual accumulation of LC neuromelanin across the lifespan, its sudden dissipation in later life, and relation to preserved cognitive function, is consistent with its complex role in normal and pathological aging.
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Affiliation(s)
| | | | | | - Eve De Rosa
- Department of Psychology, Cornell University
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Krohn F, Lancini E, Ludwig M, Leiman M, Guruprasath G, Haag L, Panczyszyn J, Düzel E, Hämmerer D, Betts M. Noradrenergic neuromodulation in ageing and disease. Neurosci Biobehav Rev 2023; 152:105311. [PMID: 37437752 DOI: 10.1016/j.neubiorev.2023.105311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 06/29/2023] [Accepted: 07/07/2023] [Indexed: 07/14/2023]
Abstract
The locus coeruleus (LC) is a small brainstem structure located in the lower pons and is the main source of noradrenaline (NA) in the brain. Via its phasic and tonic firing, it modulates cognition and autonomic functions and is involved in the brain's immune response. The extent of degeneration to the LC in healthy ageing remains unclear, however, noradrenergic dysfunction may contribute to the pathogenesis of Alzheimer's (AD) and Parkinson's disease (PD). Despite their differences in progression at later disease stages, the early involvement of the LC may lead to comparable behavioural symptoms such as preclinical sleep problems and neuropsychiatric symptoms as a result of AD and PD pathology. In this review, we draw attention to the mechanisms that underlie LC degeneration in ageing, AD and PD. We aim to motivate future research to investigate how early degeneration of the noradrenergic system may play a pivotal role in the pathogenesis of AD and PD which may also be relevant to other neurodegenerative diseases.
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Affiliation(s)
- F Krohn
- German Center for Neurodegenerative Diseases (DZNE), Otto-von-Guericke University Magdeburg, Magdeburg, Germany; Institute of Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - E Lancini
- German Center for Neurodegenerative Diseases (DZNE), Otto-von-Guericke University Magdeburg, Magdeburg, Germany; Institute of Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University Magdeburg, Magdeburg, Germany.
| | - M Ludwig
- Institute of Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University Magdeburg, Magdeburg, Germany; CBBS Center for Behavioral Brain Sciences, University of Magdeburg, Magdeburg, Germany
| | - M Leiman
- German Center for Neurodegenerative Diseases (DZNE), Otto-von-Guericke University Magdeburg, Magdeburg, Germany; Institute of Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - G Guruprasath
- German Center for Neurodegenerative Diseases (DZNE), Otto-von-Guericke University Magdeburg, Magdeburg, Germany; Institute of Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - L Haag
- Institute of Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - J Panczyszyn
- Institute of Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University Magdeburg, Magdeburg, Germany
| | - E Düzel
- German Center for Neurodegenerative Diseases (DZNE), Otto-von-Guericke University Magdeburg, Magdeburg, Germany; Institute of Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University Magdeburg, Magdeburg, Germany; Institute of Cognitive Neuroscience, University College London, London UK-WC1E 6BT, UK; CBBS Center for Behavioral Brain Sciences, University of Magdeburg, Magdeburg, Germany
| | - D Hämmerer
- German Center for Neurodegenerative Diseases (DZNE), Otto-von-Guericke University Magdeburg, Magdeburg, Germany; Institute of Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University Magdeburg, Magdeburg, Germany; Institute of Cognitive Neuroscience, University College London, London UK-WC1E 6BT, UK; CBBS Center for Behavioral Brain Sciences, University of Magdeburg, Magdeburg, Germany; Department of Psychology, University of Innsbruck, A-6020 Innsbruck, Austria
| | - M Betts
- German Center for Neurodegenerative Diseases (DZNE), Otto-von-Guericke University Magdeburg, Magdeburg, Germany; Institute of Cognitive Neurology and Dementia Research (IKND), Otto-von-Guericke University Magdeburg, Magdeburg, Germany; CBBS Center for Behavioral Brain Sciences, University of Magdeburg, Magdeburg, Germany
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7
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Dahl MJ, Bachman SL, Dutt S, Düzel S, Bodammer NC, Lindenberger U, Kühn S, Werkle-Bergner M, Mather M. The integrity of dopaminergic and noradrenergic brain regions is associated with different aspects of late-life memory performance. NATURE AGING 2023; 3:1128-1143. [PMID: 37653256 PMCID: PMC10501910 DOI: 10.1038/s43587-023-00469-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 07/14/2023] [Indexed: 09/02/2023]
Abstract
Changes in dopaminergic neuromodulation play a key role in adult memory decline. Recent research has also implicated noradrenaline in shaping late-life memory. However, it is unclear whether these two neuromodulators have distinct roles in age-related cognitive changes. Here, combining longitudinal MRI of the dopaminergic substantia nigra-ventral tegmental area (SN-VTA) and noradrenergic locus coeruleus (LC) in younger (n = 69) and older (n = 251) adults, we found that dopaminergic and noradrenergic integrity are differentially associated with memory performance. While LC integrity was related to better episodic memory across several tasks, SN-VTA integrity was linked to working memory. Longitudinally, we found that older age was associated with more negative change in SN-VTA and LC integrity. Notably, changes in LC integrity reliably predicted future episodic memory. These differential associations of dopaminergic and noradrenergic nuclei with late-life cognitive decline have potential clinical utility, given their degeneration in several age-associated diseases.
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Affiliation(s)
- Martin J Dahl
- Center for Lifespan Psychology, Max Planck Institute for Human Development, Berlin, Germany.
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA.
| | - Shelby L Bachman
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
| | - Shubir Dutt
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
- Department of Psychology, University of Southern California, Los Angeles, CA, USA
| | - Sandra Düzel
- Center for Lifespan Psychology, Max Planck Institute for Human Development, Berlin, Germany
| | - Nils C Bodammer
- Center for Lifespan Psychology, Max Planck Institute for Human Development, Berlin, Germany
| | - Ulman Lindenberger
- Center for Lifespan Psychology, Max Planck Institute for Human Development, Berlin, Germany
- Max Planck UCL Centre for Computational Psychiatry and Ageing Research, London, UK
- Max Planck UCL Centre for Computational Psychiatry and Ageing Research, Berlin, Germany
| | - Simone Kühn
- Lise Meitner Group for Environmental Neuroscience, Max Planck Institute for Human Development, Berlin, Germany
- Department of Psychiatry and Psychotherapy, University Clinic Hamburg-Eppendorf, Hamburg, Germany
| | - Markus Werkle-Bergner
- Center for Lifespan Psychology, Max Planck Institute for Human Development, Berlin, Germany
| | - Mara Mather
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
- Department of Psychology, University of Southern California, Los Angeles, CA, USA
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, USA
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8
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Van Egroo M, Riphagen JM, Ashton NJ, Janelidze S, Sperling RA, Johnson KA, Yang HS, Bennett DA, Blennow K, Hansson O, Zetterberg H, Jacobs HIL. Ultra-high field imaging, plasma markers and autopsy data uncover a specific rostral locus coeruleus vulnerability to hyperphosphorylated tau. Mol Psychiatry 2023; 28:2412-2422. [PMID: 37020050 PMCID: PMC10073793 DOI: 10.1038/s41380-023-02041-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 03/15/2023] [Accepted: 03/17/2023] [Indexed: 04/07/2023]
Abstract
Autopsy data indicate that the locus coeruleus (LC) is one of the first sites in the brain to accumulate hyperphosphorylated tau pathology, with the rostral part possibly being more vulnerable in the earlier stages of the disease. Taking advantage of recent developments in ultra-high field (7 T) imaging, we investigated whether imaging measures of the LC also reveal a specific anatomic correlation with tau using novel plasma biomarkers of different species of hyperphosphorylated tau, how early in adulthood these associations can be detected and if are associated with worse cognitive performance. To validate the anatomic correlations, we tested if a rostro-caudal gradient in tau pathology is also detected at autopsy in data from the Rush Memory and Aging Project (MAP). We found that higher plasma measures of phosphorylated tau, in particular ptau231, correlated negatively with dorso-rostral LC integrity, whereas correlations for neurodegenerative plasma markers (neurofilament light, total tau) were scattered throughout the LC including middle to caudal sections. In contrast, the plasma Aβ42/40 ratio, associated with brain amyloidosis, did not correlate with LC integrity. These findings were specific to the rostral LC and not observed when using the entire LC or the hippocampus. Furthermore, in the MAP data, we observed higher rostral than caudal tangle density in the LC, independent of the disease stage. The in vivo LC-phosphorylated tau correlations became significant from midlife, with the earliest effect for ptau231, starting at about age 55. Finally, interactions between lower rostral LC integrity and higher ptau231 concentrations predicted lower cognitive performance. Together, these findings demonstrate a specific rostral vulnerability to early phosphorylated tau species that can be detected with dedicated magnetic resonance imaging measures, highlighting the promise of LC imaging as an early marker of AD-related processes.
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Grants
- R01 AG017917 NIA NIH HHS
- R01 AG068398 NIA NIH HHS
- R21 AG074220 NIA NIH HHS
- K23 AG062750 NIA NIH HHS
- R01 AG068062 NIA NIH HHS
- K01 AG001016 NIA NIH HHS
- ZEN-21-848495 Alzheimer's Association
- P01 AG036694 NIA NIH HHS
- R01 AG062559 NIA NIH HHS
- R01 AG015819 NIA NIH HHS
- U.S. Department of Health & Human Services | NIH | National Institute on Aging (U.S. National Institute on Aging)
- Alzheimer Nederland WE.03-2019-02
- BrightFocus Foundation (BrightFocus)
- Alzheimer’s Association
- Alzheimer’s Drug Discovery Foundation (ADDF)
- Swedish Research Council (#2017-00915), the Alzheimer Drug Discovery Foundation (ADDF), USA (#RDAPB-201809-2016615), the Swedish Alzheimer Foundation (#AF-930351, #AF-939721 and #AF-968270), Hjärnfonden, Sweden (#FO2017-0243 and #ALZ2022-0006), the Swedish state under the agreement between the Swedish government and the County Councils, the ALF-agreement (#ALFGBG-715986 and #ALFGBG-965240), the European Union Joint Program for Neurodegenerative Disorders (JPND2019-466-236)
- Cure Alzheimer’s Fund (Alzheimer’s Disease Research Foundation)
- Swedish Research Council (2016-00906), the Knut and Alice Wallenberg foundation (2017-0383), the Marianne and Marcus Wallenberg foundation (2015.0125), the Strategic Research Area MultiPark (Multidisciplinary Research in Parkinson’s disease) at Lund University, the Swedish Alzheimer Foundation (AF-939932), the Swedish Brain Foundation (FO2021-0293), The Parkinson foundation of Sweden (1280/20), the Cure Alzheimer’s fund, the Konung Gustaf V:s och Drottning Victorias Frimurarestiftelse, the Skåne University Hospital Foundation (2020-O000028), Regionalt Forskningsstöd (2020-0314) and the Swedish federal government under the ALF agreement (2018-Projekt0279)
- HZ is a Wallenberg Scholar supported by grants from the Swedish Research Council (#2018-02532), the European Research Council (#681712 and #101053962), Swedish State Support for Clinical Research (#ALFGBG-71320), the Alzheimer Drug Discovery Foundation (ADDF), USA (#201809-2016862), the AD Strategic Fund and the Alzheimer’s Association (#ADSF-21-831376-C, #ADSF-21-831381-C, and #ADSF-21-831377-C), the Bluefield Project, the Olav Thon Foundation, the Erling-Persson Family Foundation, Stiftelsen för Gamla Tjänarinnor, Hjärnfonden, Sweden (#FO2022-0270), the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 860197 (MIRIADE), the European Union Joint Programme – Neurodegenerative Disease Research (JPND2021-00694), and the UK Dementia Research Institute at UCL (UKDRI-1003).
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Affiliation(s)
- Maxime Van Egroo
- Faculty of Health, Medicine and Life Sciences, School for Mental Health and Neuroscience, Alzheimer Centre Limburg, Maastricht University, Maastricht, The Netherlands
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Joost M Riphagen
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Nicholas J Ashton
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Centre for Age-Related Medicine, Stavanger University Hospital, Stavanger, Norway
- King's College London, Institute of Psychiatry, Psychology and Neuroscience, Maurice Wohl Institute Clinical Neuroscience Institute, London, UK
- NIHR Biomedical Research Centre for Mental Health and Biomedical Research Unit for Dementia at South London and Maudsley NHS Foundation, London, UK
| | - Shorena Janelidze
- Clinical Memory Research Unit, Department of Clinical Sciences Malmö, Lund University, Lund, Sweden
| | - Reisa A Sperling
- Harvard Medical School, Boston, MA, USA
- Center for Alzheimer Research and Treatment, Department of Neurology, Brigham and Women's Hospital, Boston, MA, USA
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - Keith A Johnson
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - Hyun-Sik Yang
- Harvard Medical School, Boston, MA, USA
- Center for Alzheimer Research and Treatment, Department of Neurology, Brigham and Women's Hospital, Boston, MA, USA
- Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - David A Bennett
- Department of Neurological Sciences, Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, 60612, USA
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Oskar Hansson
- Clinical Memory Research Unit, Department of Clinical Sciences Malmö, Lund University, Lund, Sweden
- Memory Clinic, Skåne University Hospital, Malmö, Sweden
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
- Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK
- UK Dementia Research Institute at UCL, London, UK
- Hong Kong Center for Neurodegenerative Diseases, Clear Water Bay, Hong Kong, China
| | - Heidi I L Jacobs
- Faculty of Health, Medicine and Life Sciences, School for Mental Health and Neuroscience, Alzheimer Centre Limburg, Maastricht University, Maastricht, The Netherlands.
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA, USA.
- Harvard Medical School, Boston, MA, USA.
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9
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Benarroch E. What Are Current Concepts on the Functional Organization of the Locus Coeruleus and Its Role in Cognition and Neurodegeneration? Neurology 2023; 100:132-137. [PMID: 36646470 DOI: 10.1212/wnl.0000000000206736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 11/09/2022] [Indexed: 01/18/2023] Open
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10
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Vicente MC, Paneghini JL, Stabile AM, Amorim M, Anibal Silva CE, Patrone LGA, Cunha TM, Bícego KC, Almeida MC, Carrettiero DC, Gargaglioni LH. Inhibition of Pro-Inflammatory Microglia with Minocycline Improves Cognitive and Sleep-Wake Dysfunction Under Respiratory Stress in a Sporadic Model for Alzheimer's Disease. J Alzheimers Dis 2023; 95:317-337. [PMID: 37522205 DOI: 10.3233/jad-230151] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/01/2023]
Abstract
BACKGROUND Neuroinflammation in Alzheimer's disease (AD) can occur due to excessive activation of microglia in response to the accumulation of amyloid-β peptide (Aβ). Previously, we demonstrated an increased expression of this peptide in the locus coeruleus (LC) in a sporadic model for AD (streptozotocin, STZ; 2 mg/kg, ICV). We hypothesized that the STZ-AD model exhibits neuroinflammation, and treatment with an inhibitor of microglia (minocycline) can reverse the cognitive, respiratory, sleep, and molecular disorders of this model. OBJECTIVE To evaluate the effect of minocycline treatment in STZ model disorders. METHODS We treated control and STZ-treated rats for five days with minocycline (30 mg/kg, IP) and evaluated cognitive performance, chemoreflex response to hypercapnia and hypoxia, and total sleep time. Additionally, quantification of Aβ, microglia analyses, and relative expression of cytokines in the LC were performed. RESULTS Minocycline treatment improved learning and memory, which was concomitant with a decrease in microglial cell density and re-establishment of morphological changes induced by STZ in the LC region. Minocycline did not reverse the STZ-induced increase in CO2 sensitivity during wakefulness. However, it restored the daytime sleep-wake cycle in STZ-treated animals to the same levels as those observed in control animals. In the LC, levels of A and expression of Il10, Il1b, and Mcp1 mRNA remained unaffected by minocycline, but we found a strong trend of minocycline effect on Tnf- α. CONCLUSION Our findings suggest that minocycline effectively reduces microglial recruitment and the inflammatory morphological profile in the LC, while it recovers cognitive performance and restores the sleep-wake pattern impaired by STZ.
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Affiliation(s)
- Mariane C Vicente
- Department of Animal Morphology and Physiology, Sao Paulo State University - UNESP/FCAV, Jaboticabal, SP, Brazil
- Mary S. Easton Center for Alzheimer's Research and Care, Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Julia L Paneghini
- Department of Animal Morphology and Physiology, Sao Paulo State University - UNESP/FCAV, Jaboticabal, SP, Brazil
| | - Angelita M Stabile
- Department of General and Specialized Nursing, School of Nursing of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Mateus Amorim
- Department of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Conceição E Anibal Silva
- Department of Pharmachology, Medicine School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Luis Gustavo A Patrone
- Department of Animal Morphology and Physiology, Sao Paulo State University - UNESP/FCAV, Jaboticabal, SP, Brazil
| | - Thiago M Cunha
- Department of Pharmachology, Medicine School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Kênia C Bícego
- Department of Animal Morphology and Physiology, Sao Paulo State University - UNESP/FCAV, Jaboticabal, SP, Brazil
| | - Maria C Almeida
- Center for Natural and Human Sciences, Federal University of ABC, São Bernardo do Campo, Brazil
| | - Daniel C Carrettiero
- Center for Natural and Human Sciences, Federal University of ABC, São Bernardo do Campo, Brazil
| | - Luciane H Gargaglioni
- Department of Animal Morphology and Physiology, Sao Paulo State University - UNESP/FCAV, Jaboticabal, SP, Brazil
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11
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Minné D, Marnewick JL, Engel-Hills P. Early Chronic Stress Induced Changes within the Locus Coeruleus in Sporadic Alzheimer's Disease. Curr Alzheimer Res 2023; 20:301-317. [PMID: 37872793 DOI: 10.2174/1567205020666230811092956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 06/30/2023] [Accepted: 07/04/2023] [Indexed: 10/25/2023]
Abstract
Chronic exposure to stress throughout the lifespan has been the focus of many studies on Alzheimer's disease (AD) because of the similarities between the biological mechanisms involved in chronic stress and the pathophysiology of AD. In fact, the earliest abnormality associated with the disease is the presence of phosphorylated tau protein in locus coeruleus neurons, a brain structure highly responsive to stress and perceived threat. Here, we introduce allostatic load as a useful concept for understanding many of the complex, interacting neuropathological changes involved in the AD degenerative process. In response to chronic stress, aberrant tau proteins that begin to accumulate within the locus coeruleus decades prior to symptom onset appear to represent a primary pathological event in the AD cascade, triggering a wide range of interacting brain changes involving neuronal excitotoxicity, endocrine alterations, inflammation, oxidative stress, and amyloid plaque exacerbation. While it is acknowledged that stress will not necessarily be the major precipitating factor in all cases, early tau-induced changes within the locus coeruleus-norepinephrine pathway suggests that a therapeutic window might exist for preventative measures aimed at managing stress and restoring balance within the HPA axis.
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Affiliation(s)
- Donné Minné
- Applied Microbial & Health Biotechnology Institute, Cape Peninsula University of Technology, Cape Town, 7535, South Africa
- Faculty of Health and Wellness Sciences, Cape Peninsula University of Technology, Cape Town, 7535, South Africa
| | - Jeanine L Marnewick
- Applied Microbial & Health Biotechnology Institute, Cape Peninsula University of Technology, Cape Town, 7535, South Africa
| | - Penelope Engel-Hills
- Faculty of Health and Wellness Sciences, Cape Peninsula University of Technology, Cape Town, 7535, South Africa
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12
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Bolton CJ, Tam JW. Differential Involvement of the Locus Coeruleus in Early- and Late-Onset Alzheimer's Disease: A Potential Mechanism of Clinical Differences? J Geriatr Psychiatry Neurol 2022; 35:733-739. [PMID: 34496652 DOI: 10.1177/08919887211044755] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Sporadic early-onset Alzheimer's disease (sEOAD) is often associated with atypical clinical features, yet the cause of this heterogeneity remains unclear. This study investigated post-mortem atrophy of the locus coeruleus (LC) in sEOAD and late-onset Alzheimer's disease (LOAD). Levels of LC atrophy, as estimated by pathologist-rating of hypopigmentation, were compared between sEOAD (n = 115) and LOAD (n = 672) participants while controlling for other measures of pathological progression. Subsequent analyses compared low vs. high LC atrophy sEOAD subgroups on neuropsychological test performance. Results show nearly 4 times greater likelihood of higher LC atrophy in sEOAD as compared to LOAD (p < .005). sEOAD participants with greater LC atrophy displayed significantly worse performance on various baseline measures of attentional functioning (p < .05), despite similar global cognition (p = .25). These findings suggest the LC is an important potential driver of clinical and pathological heterogeneity in sEOAD.
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Affiliation(s)
- Corey J Bolton
- Vanderbilt Memory and Alzheimer's Center, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Joyce W Tam
- Department of Psychiatry and Behavioral Sciences, Rush University Medical Center, Chicago, IL, USA
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13
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Dahl MJ, Mather M, Werkle-Bergner M, Kennedy BL, Guzman S, Hurth K, Miller CA, Qiao Y, Shi Y, Chui HC, Ringman JM. Locus coeruleus integrity is related to tau burden and memory loss in autosomal-dominant Alzheimer's disease. Neurobiol Aging 2022; 112:39-54. [PMID: 35045380 PMCID: PMC8976827 DOI: 10.1016/j.neurobiolaging.2021.11.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 11/17/2021] [Accepted: 11/26/2021] [Indexed: 12/14/2022]
Abstract
Abnormally phosphorylated tau, an indicator of Alzheimer's disease, accumulates in the first decades of life in the locus coeruleus (LC), the brain's main noradrenaline supply. However, technical challenges in in-vivo assessments have impeded research into the role of the LC in Alzheimer's disease. We studied participants with or known to be at-risk for mutations in genes causing autosomal-dominant Alzheimer's disease (ADAD) with early onset, providing a unique window into the pathogenesis of Alzheimer's largely disentangled from age-related factors. Using high-resolution MRI and tau PET, we found lower rostral LC integrity in symptomatic participants. LC integrity was associated with individual differences in tau burden and memory decline. Post-mortem analyses in a separate set of carriers of the same mutation confirmed substantial neuronal loss in the LC. Our findings link LC degeneration to tau burden and memory in Alzheimer's, and highlight a role of the noradrenergic system in this neurodegenerative disease.
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Affiliation(s)
- Martin J Dahl
- Center for Lifespan Psychology, Max Planck Institute for Human Development, Berlin, Germany; Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA.
| | - Mara Mather
- Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
| | - Markus Werkle-Bergner
- Center for Lifespan Psychology, Max Planck Institute for Human Development, Berlin, Germany
| | - Briana L Kennedy
- Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA; School of Psychological Science, University of Western Australia, Perth, Australia
| | - Samuel Guzman
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Kyle Hurth
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Carol A Miller
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Yuchuan Qiao
- Laboratory of Neuro Imaging (LONI), USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Yonggang Shi
- Laboratory of Neuro Imaging (LONI), USC Stevens Neuroimaging and Informatics Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Helena C Chui
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - John M Ringman
- Department of Neurology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
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14
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Llamas-Rodríguez J, Oltmer J, Greve DN, Williams E, Slepneva N, Wang R, Champion S, Lang-Orsini M, Fischl B, Frosch MP, van der Kouwe AJ, Augustinack JC. Entorhinal Subfield Vulnerability to Neurofibrillary Tangles in Aging and the Preclinical Stage of Alzheimer's Disease. J Alzheimers Dis 2022; 87:1379-1399. [PMID: 35491780 PMCID: PMC9198759 DOI: 10.3233/jad-215567] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/25/2022] [Indexed: 12/15/2022]
Abstract
BACKGROUND Neurofibrillary tangle (NFT) accumulation in the entorhinal cortex (EC) precedes the transformation from cognitive controls to mild cognitive impairment and Alzheimer's disease (AD). While tauopathy has been described in the EC before, the order and degree to which the individual subfields within the EC are engulfed by NFTs in aging and the preclinical AD stage is unknown. OBJECTIVE We aimed to investigate substructures within the EC to map the populations of cortical neurons most vulnerable to tau pathology in aging and the preclinical AD stage. METHODS We characterized phosphorylated tau (CP13) in 10 cases at eight well-defined anterior-posterior levels and assessed NFT density within the eight entorhinal subfields (described by Insausti and colleagues) at the preclinical stages of AD. We validated with immunohistochemistry and labeled the NFT density ratings on ex vivo MRIs. We measured subfield cortical thickness and reconstructed the labels as three-dimensional isosurfaces, resulting in anatomically comprehensive, histopathologically validated tau "heat maps." RESULTS We found the lateral EC subfields ELc, ECL, and ECs (lateral portion) to have the highest tau density in semi-quantitative scores and quantitative measurements. We observed significant stepwise higher tau from anterior to posterior levels (p < 0.001). We report an age-dependent anatomically-specific vulnerability, with all cases showing posterior tau pathology, yet older individuals displaying an additional anterior tau burden. Finally, cortical thickness of each subfield negatively correlated with respective tau scores (p < 0.05). CONCLUSION Our findings indicate that posterior-lateral subfields within the EC are the most vulnerable to early NFTs and atrophy in aging and preclinical AD.
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Affiliation(s)
- Josué Llamas-Rodríguez
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Jan Oltmer
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Douglas N. Greve
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Emily Williams
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Natalya Slepneva
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Ruopeng Wang
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Samantha Champion
- Department of Neuropathology, Massachusetts General Hospital, Boston, MA, USA
| | - Melanie Lang-Orsini
- Department of Neuropathology, Massachusetts General Hospital, Boston, MA, USA
| | - Bruce Fischl
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
- CSAIL/HST, MIT, Cambridge, MA, USA
| | - Matthew P. Frosch
- Department of Neuropathology, Massachusetts General Hospital, Boston, MA, USA
| | - André J.W. van der Kouwe
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
| | - Jean C. Augustinack
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, USA
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15
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Gilvesy A, Husen E, Magloczky Z, Mihaly O, Hortobágyi T, Kanatani S, Heinsen H, Renier N, Hökfelt T, Mulder J, Uhlen M, Kovacs GG, Adori C. Spatiotemporal characterization of cellular tau pathology in the human locus coeruleus-pericoerulear complex by three-dimensional imaging. Acta Neuropathol 2022; 144:651-676. [PMID: 36040521 PMCID: PMC9468059 DOI: 10.1007/s00401-022-02477-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 07/28/2022] [Accepted: 07/29/2022] [Indexed: 01/28/2023]
Abstract
Tau pathology of the noradrenergic locus coeruleus (LC) is a hallmark of several age-related neurodegenerative disorders, including Alzheimer's disease. However, a comprehensive neuropathological examination of the LC is difficult due to its small size and rod-like shape. To investigate the LC cytoarchitecture and tau cytoskeletal pathology in relation to possible propagation patterns of disease-associated tau in an unprecedented large-scale three-dimensional view, we utilized volume immunostaining and optical clearing technology combined with light sheet fluorescence microscopy. We examined AT8+ pathological tau in the LC/pericoerulear region of 20 brains from Braak neurofibrillary tangle (NFT) stage 0-6. We demonstrate an intriguing morphological complexity and heterogeneity of AT8+ cellular structures in the LC, representing various intracellular stages of NFT maturation and their diverse transition forms. We describe novel morphologies of neuronal tau pathology such as AT8+ cells with fine filamentous somatic protrusions or with disintegrating soma. We show that gradual dendritic atrophy is the first morphological sign of the degeneration of tangle-bearing neurons, even preceding axonal lesions. Interestingly, irrespective of the Braak NFT stage, tau pathology is more advanced in the dorsal LC that preferentially projects to vulnerable forebrain regions in Alzheimer's disease, like the hippocampus or neocortical areas, compared to the ventral LC projecting to the cerebellum and medulla. Moreover, already in the precortical Braak 0 stage, 3D analysis reveals clustering tendency and dendro-dendritic close appositions of AT8+ LC neurons, AT8+ long axons of NFT-bearing cells that join the ascending dorsal noradrenergic bundle after leaving the LC, as well as AT8+ processes of NFT-bearing LC neurons that target the 4th ventricle wall. Our study suggests that the unique cytoarchitecture, comprised of a densely packed and dendritically extensively interconnected neuronal network with long projections, makes the human LC to be an ideal anatomical template for early accumulation and trans-neuronal spreading of hyperphosphorylated tau.
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Affiliation(s)
- Abris Gilvesy
- Department of Neuroscience, Karolinska Institutet, Solnavägen 9, 17177, Stockholm, Sweden
- McGill University, Montreal, QC, H3A 0G4, Canada
| | - Evelina Husen
- Department of Neuroscience, Karolinska Institutet, Solnavägen 9, 17177, Stockholm, Sweden
| | - Zsofia Magloczky
- Human Brain Research Laboratory, Institute of Experimental Medicine, ELKH, Budapest, Hungary
| | - Orsolya Mihaly
- Department of Pathology, St. Borbála Hospital, Tatabánya, Hungary
| | - Tibor Hortobágyi
- Department of Neurology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
- Department of Old Age Psychiatry, Institute of Psychiatry Psychology and Neuroscience, King's College London, London, UK
- Centre for Age-Related Medicine, SESAM, Stavanger University Hospital, Stavanger, Norway
- Institute of Neuropathology, University of Zurich, Zurich, Switzerland
| | - Shigeaki Kanatani
- Department of Medical Biochemistry and Biophysics, Karolinska Institutet, 17177, Stockholm, Sweden
| | - Helmut Heinsen
- Clinic of Psychiatry and Institute of Forensic Pathology, University of Würzburg, 97080, Würzburg, Germany
- LIM-44, University of Sao Paulo Medical School, Sao Paulo, Brazil
| | - Nicolas Renier
- Sorbonne Université, Paris Brain Institute-ICM, INSERM, CNRS, AP-HP, Hôpital de la Pitié Salpêtrière, 75013, Paris, France
| | - Tomas Hökfelt
- Department of Neuroscience, Karolinska Institutet, Solnavägen 9, 17177, Stockholm, Sweden
| | - Jan Mulder
- Department of Neuroscience, Karolinska Institutet, Solnavägen 9, 17177, Stockholm, Sweden
| | - Mathias Uhlen
- Department of Neuroscience, Karolinska Institutet, Solnavägen 9, 17177, Stockholm, Sweden
- Science for Life Laboratory, Royal Institute of Technology, 10691, Stockholm, Sweden
| | - Gabor G Kovacs
- Tanz Centre for Research in Neurodegenerative Disease and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
- Laboratory Medicine Program and Krembil Brain Institute, University Health Network, Toronto, ON, Canada
| | - Csaba Adori
- Department of Neuroscience, Karolinska Institutet, Solnavägen 9, 17177, Stockholm, Sweden.
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16
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Dahl MJ, Mather M, Werkle-Bergner M. Noradrenergic modulation of rhythmic neural activity shapes selective attention. Trends Cogn Sci 2022; 26:38-52. [PMID: 34799252 PMCID: PMC8678372 DOI: 10.1016/j.tics.2021.10.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 10/12/2021] [Accepted: 10/12/2021] [Indexed: 01/03/2023]
Abstract
During moments involving selective attention, the thalamus orchestrates the preferential processing of prioritized information by coordinating rhythmic neural activity within a distributed frontoparietal network. The timed release of neuromodulators from subcortical structures dynamically sculpts neural synchronization in thalamocortical networks to meet current attentional demands. In particular, noradrenaline modulates the balance of cortical excitation and inhibition, as reflected by thalamocortical alpha synchronization (~8-12 Hz). These neuromodulatory adjustments facilitate the selective processing of prioritized information. Thus, by disrupting effective rhythmic coordination in attention networks, age-related locus coeruleus (LC) degeneration can impair higher levels of neural processing. In sum, findings across different levels of analysis and modalities shed light on how the noradrenergic modulation of neural synchronization helps to shape selective attention.
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Affiliation(s)
- Martin J Dahl
- Center for Lifespan Psychology, Max Planck Institute for Human Development, 14195 Berlin, Germany; Davis School of Gerontology, University of Southern California, 90089 Los Angeles, CA, USA.
| | - Mara Mather
- Davis School of Gerontology, University of Southern California, 90089 Los Angeles, CA, USA
| | - Markus Werkle-Bergner
- Center for Lifespan Psychology, Max Planck Institute for Human Development, 14195 Berlin, Germany
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17
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Levey AI, Qiu D, Zhao L, Hu WT, Duong DM, Higginbotham L, Dammer EB, Seyfried NT, Wingo TS, Hales CM, Gámez Tansey M, Goldstein DS, Abrol A, Calhoun VD, Goldstein FC, Hajjar I, Fagan AM, Galasko D, Edland SD, Hanfelt J, Lah JJ, Weinshenker D. A phase II study repurposing atomoxetine for neuroprotection in mild cognitive impairment. Brain 2021; 145:1924-1938. [PMID: 34919634 DOI: 10.1093/brain/awab452] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Revised: 11/08/2021] [Accepted: 11/19/2021] [Indexed: 11/12/2022] Open
Abstract
The locus coeruleus (LC) is the initial site of Alzheimer's disease neuropathology, with hyperphosphorylated Tau appearing in early adulthood followed by neurodegeneration in dementia. LC dysfunction contributes to Alzheimer's pathobiology in experimental models, which can be rescued by increasing norepinephrine (NE) transmission. To test NE augmentation as a potential disease-modifying therapy, we performed a biomarker-driven phase II trial of atomoxetine, a clinically-approved NE transporter inhibitor, in subjects with mild cognitive impairment due to Alzheimer's disease. The design was a single-center, 12-month double-blind crossover trial. Thirty-nine participants with mild cognitive impairment (MCI) and biomarker evidence of Alzheimer's disease were randomized to atomoxetine or placebo treatment. Assessments were collected at baseline, 6- (crossover) and 12-months (completer). Target engagement was assessed by CSF and plasma measures of NE and metabolites. Prespecified primary outcomes were CSF levels of IL1α and Thymus-Expressed Chemokine. Secondary/exploratory outcomes included clinical measures, CSF analyses of Aβ42, Tau, and pTau181, mass spectrometry proteomics, and immune-based targeted inflammation-related cytokines, as well as brain imaging with MRI and FDG-PET. Baseline demographic and clinical measures were similar across trial arms. Dropout rates were 5.1% for atomoxetine and 2.7% for placebo, with no significant differences in adverse events. Atomoxetine robustly increased plasma and CSF NE levels. IL-1α and Thymus-Expressed Chemokine were not measurable in most samples. There were no significant treatment effects on cognition and clinical outcomes, as expected given the short trial duration. Atomoxetine was associated with a significant reduction in CSF Tau and pTau181 compared to placebo, but not associated with change in Aβ42. Atomoxetine treatment also significantly altered CSF abundances of protein panels linked to brain pathophysiologies, including synaptic, metabolism, and glial immunity, as well as inflammation-related CDCP1, CD244, TWEAK, and OPG proteins. Treatment was also associated with significantly increased BDNF and reduced triglycerides in plasma. Resting state fMRI showed significantly increased inter-network connectivity due to atomoxetine between the insula and the hippocampus. FDG-PET showed atomoxetine-associated increased uptake in hippocampus, parahippocampal gyrus, middle temporal pole, inferior temporal gyrus, and fusiform gyrus, with carry-over effects six months after treatment. In summary, atomoxetine treatment was safe, well tolerated, and achieved target engagement in prodromal Alzheimer's disease. Atomoxetine significantly reduced CSF Tau and pTau, normalized CSF protein biomarker panels linked to synaptic function, brain metabolism, and glial immunity, and increased brain activity and metabolism in key temporal lobe circuits. Further study of atomoxetine is warranted for repurposing the drug to slow Alzheimer's disease progression.
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Affiliation(s)
- Allan I Levey
- Goizueta Alzheimer's Disease Research Center, Emory University, Atlanta, Georgia, 30322, USA.,Department of Neurology, Emory University, Atlanta, Georgia, 30322, USA
| | - Deqiang Qiu
- Goizueta Alzheimer's Disease Research Center, Emory University, Atlanta, Georgia, 30322, USA.,Department of Radiology and Imaging Sciences, Emory University, Atlanta, Georgia, 30322, USA
| | - Liping Zhao
- Goizueta Alzheimer's Disease Research Center, Emory University, Atlanta, Georgia, 30322, USA.,Department of Biostatistics, Emory University, Atlanta, Georgia, 30322, USA
| | - William T Hu
- Goizueta Alzheimer's Disease Research Center, Emory University, Atlanta, Georgia, 30322, USA.,Department of Neurology, Emory University, Atlanta, Georgia, 30322, USA
| | - Duc M Duong
- Department of Biochemistry, Emory University, Atlanta, Georgia, 30322, USA
| | - Lenora Higginbotham
- Goizueta Alzheimer's Disease Research Center, Emory University, Atlanta, Georgia, 30322, USA
| | - Eric B Dammer
- Department of Biochemistry, Emory University, Atlanta, Georgia, 30322, USA
| | - Nicholas T Seyfried
- Goizueta Alzheimer's Disease Research Center, Emory University, Atlanta, Georgia, 30322, USA.,Department of Biochemistry, Emory University, Atlanta, Georgia, 30322, USA
| | - Thomas S Wingo
- Goizueta Alzheimer's Disease Research Center, Emory University, Atlanta, Georgia, 30322, USA.,Department of Neurology, Emory University, Atlanta, Georgia, 30322, USA.,Department of Human Genetics, Emory University, Atlanta, Georgia, 30322, USA
| | - Chadwick M Hales
- Goizueta Alzheimer's Disease Research Center, Emory University, Atlanta, Georgia, 30322, USA.,Department of Neurology, Emory University, Atlanta, Georgia, 30322, USA
| | - Malú Gámez Tansey
- Department of Physiology, Emory University, Atlanta, Georgia, 30322, USA
| | | | - Anees Abrol
- Tri-institutional Center for Translational Research in Neuroimaging and Data Science (TReNDS), Georgia State University, Georgia Institute of Technology, Emory University, Atlanta, GA, 30303, USA
| | - Vince D Calhoun
- Tri-institutional Center for Translational Research in Neuroimaging and Data Science (TReNDS), Georgia State University, Georgia Institute of Technology, Emory University, Atlanta, GA, 30303, USA
| | - Felicia C Goldstein
- Goizueta Alzheimer's Disease Research Center, Emory University, Atlanta, Georgia, 30322, USA.,Department of Neurology, Emory University, Atlanta, Georgia, 30322, USA
| | - Ihab Hajjar
- Goizueta Alzheimer's Disease Research Center, Emory University, Atlanta, Georgia, 30322, USA.,Department of Neurology, Emory University, Atlanta, Georgia, 30322, USA
| | - Anne M Fagan
- Department of Neurology and Knight ADRC, Washington University, St. Louis, MO, 630130, USA
| | - Doug Galasko
- Department of Neurosciences and ADRC, UCSD, San Diego, CA, 92093, USA
| | - Steven D Edland
- Department of Neurosciences and ADRC, UCSD, San Diego, CA, 92093, USA
| | - John Hanfelt
- Goizueta Alzheimer's Disease Research Center, Emory University, Atlanta, Georgia, 30322, USA.,Department of Biostatistics, Emory University, Atlanta, Georgia, 30322, USA
| | - James J Lah
- Goizueta Alzheimer's Disease Research Center, Emory University, Atlanta, Georgia, 30322, USA.,Department of Neurology, Emory University, Atlanta, Georgia, 30322, USA
| | - David Weinshenker
- Goizueta Alzheimer's Disease Research Center, Emory University, Atlanta, Georgia, 30322, USA.,Department of Human Genetics, Emory University, Atlanta, Georgia, 30322, USA
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18
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Ledreux A, Thomas S, Hamlett ED, Trautman C, Gilmore A, Rickman Hager E, Paredes DA, Margittai M, Fortea J, Granholm AC. Small Neuron-Derived Extracellular Vesicles from Individuals with Down Syndrome Propagate Tau Pathology in the Wildtype Mouse Brain. J Clin Med 2021; 10:3931. [PMID: 34501378 PMCID: PMC8432237 DOI: 10.3390/jcm10173931] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 08/24/2021] [Accepted: 08/28/2021] [Indexed: 12/11/2022] Open
Abstract
Individuals with Down syndrome (DS) exhibit Alzheimer's disease (AD) pathology at a young age, including amyloid plaques and neurofibrillary tangles (NFTs). Tau pathology can spread via extracellular vesicles, such as exosomes. The cargo of neuron-derived small extracellular vesicles (NDEVs) from individuals with DS contains p-Tau at an early age. The goal of the study was to investigate whether NDEVs isolated from the blood of individuals with DS can spread Tau pathology in the brain of wildtype mice. We purified NDEVs from the plasma of patients with DS-AD and controls and injected small quantities using stereotaxic surgery into the dorsal hippocampus of adult wildtype mice. Seeding competent Tau conformers were amplified in vitro from DS-AD NDEVs but not NDEVs from controls. One month or 4 months post-injection, we examined Tau pathology in mouse brains. We found abundant p-Tau immunostaining in the hippocampus of the mice injected with DS-AD NDEVs compared to injections of age-matched control NDEVs. Double labeling with neuronal and glial markers showed that p-Tau staining was largely found in neurons and, to a lesser extent, in glial cells and that p-Tau immunostaining was spreading along the corpus callosum and the medio-lateral axis of the hippocampus. These studies demonstrate that NDEVs from DS-AD patients exhibit Tau seeding capacity and give rise to tangle-like intracellular inclusions.
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Affiliation(s)
- Aurélie Ledreux
- Knoebel Institute for Healthy Aging, University of Denver, Denver, CO 80208, USA; (S.T.); (C.T.); (A.G.); (D.A.P.); (A.-C.G.)
| | - Sarah Thomas
- Knoebel Institute for Healthy Aging, University of Denver, Denver, CO 80208, USA; (S.T.); (C.T.); (A.G.); (D.A.P.); (A.-C.G.)
| | - Eric D. Hamlett
- Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, SC 29425, USA;
| | - Camille Trautman
- Knoebel Institute for Healthy Aging, University of Denver, Denver, CO 80208, USA; (S.T.); (C.T.); (A.G.); (D.A.P.); (A.-C.G.)
| | - Anah Gilmore
- Knoebel Institute for Healthy Aging, University of Denver, Denver, CO 80208, USA; (S.T.); (C.T.); (A.G.); (D.A.P.); (A.-C.G.)
| | - Emily Rickman Hager
- Department of Chemistry and Biochemistry, University of Denver, Denver, CO 80208, USA; (E.R.H.); (M.M.)
| | - Daniel A. Paredes
- Knoebel Institute for Healthy Aging, University of Denver, Denver, CO 80208, USA; (S.T.); (C.T.); (A.G.); (D.A.P.); (A.-C.G.)
| | - Martin Margittai
- Department of Chemistry and Biochemistry, University of Denver, Denver, CO 80208, USA; (E.R.H.); (M.M.)
| | - Juan Fortea
- Hospital de la Santa Creu i Sant Pau and Catalan Down Syndrome Foundation, 08041 Barcelona, Spain;
| | - Ann-Charlotte Granholm
- Knoebel Institute for Healthy Aging, University of Denver, Denver, CO 80208, USA; (S.T.); (C.T.); (A.G.); (D.A.P.); (A.-C.G.)
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19
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Physiological separation of Alzheimer's disease and Alzheimer's disease with significant levels of cerebrovascular symptomology and healthy controls. Med Biol Eng Comput 2021; 59:1597-1610. [PMID: 34263439 DOI: 10.1007/s11517-021-02409-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Accepted: 07/04/2021] [Indexed: 01/14/2023]
Abstract
Most dementia patients with a mixed dementia (MxD) diagnosis have a mix of Alzheimer's disease (AD) and vascular dementia. Electrovestibulography (EVestG) records vestibuloacoustic afferent activity. We hypothesize EVestG recordings of AD and MxD patients are different. All patients were assessed with the Montreal cognitive assessment (MoCA) and Hachinski ischemic scale (HIS) (> 4 HIS score < 7 is representative of MxD cerebrovascular symptomology). EVestG recordings were made from 26 AD, 21 MxD and 44 healthy (control) participants. Features were derived from the EVestG recordings of the average field potential and field potential interval histogram to classify the AD, MxD and control groups. Multivariate analysis was used to test the features' significance. Using a leave-one-out cross-validated linear discriminant analysis with 3 EVestG features yielded accuracies > 80% for separating pairs of AD/MxD/control. Using the MoCA assessment and 2 EVestG features, a best accuracy of 81 to 91% depending on the classifier was obtained for the 3-way identification of AD, MxD and controls. EVestG measures provide a physiological basis for identifying AD from MxD. EVestG measures are hypothesized to be partly related to channelopathies and changes in the descending input to the vestibular periphery. Four of the five AD or MxD versus control features used had significant correlations with the MoCA. This supports assertions that the pathologic changes associated with AD impact the vestibular system and further are suggestive that the postulated physiological changes behind these features have an association with cognitive decline severity.
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20
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Giorgi FS, Galgani A, Puglisi-Allegra S, Busceti CL, Fornai F. The connections of Locus Coeruleus with hypothalamus: potential involvement in Alzheimer's disease. J Neural Transm (Vienna) 2021; 128:589-613. [PMID: 33942174 PMCID: PMC8105225 DOI: 10.1007/s00702-021-02338-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 04/14/2021] [Indexed: 12/19/2022]
Abstract
The hypothalamus and Locus Coeruleus (LC) share a variety of functions, as both of them take part in the regulation of the sleep/wake cycle and in the modulation of autonomic and homeostatic activities. Such a functional interplay takes place due to the dense and complex anatomical connections linking the two brain structures. In Alzheimer's disease (AD), the occurrence of endocrine, autonomic and sleep disturbances have been associated with the disruption of the hypothalamic network; at the same time, in this disease, the occurrence of LC degeneration is receiving growing attention for the potential roles it may have both from a pathophysiological and pathogenetic point of view. In this review, we summarize the current knowledge on the anatomical and functional connections between the LC and hypothalamus, to better understand whether the impairment of the former may be responsible for the pathological involvement of the latter, and whether the disruption of their interplay may concur to the pathophysiology of AD. Although only a few papers specifically explored this topic, intriguingly, some pre-clinical and post-mortem human studies showed that aberrant protein spreading and neuroinflammation may cause hypothalamus degeneration and that these pathological features may be linked to LC impairment. Moreover, experimental studies in rodents showed that LC plays a relevant role in modulating the hypothalamic sleep/wake cycle regulation or neuroendocrine and systemic hormones; in line with this, the degeneration of LC itself may partly explain the occurrence of hypothalamic-related symptoms in AD.
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Affiliation(s)
- Filippo Sean Giorgi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126, Pisa, Italy
| | | | | | | | - Francesco Fornai
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Via Roma 55, 56126, Pisa, Italy.
- I.R.C.C.S. Neuromed, Via Atinense 18, 86077, Pozzilli, IS, Italy.
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21
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Dutt S, Li Y, Mather M, Nation DA. Brainstem substructures and cognition in prodromal Alzheimer's disease. Brain Imaging Behav 2021; 15:2572-2582. [PMID: 33646514 PMCID: PMC8500899 DOI: 10.1007/s11682-021-00459-y] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/28/2021] [Indexed: 12/26/2022]
Abstract
Neuropathological research suggests the tau pathology of Alzheimer's disease may originate in brainstem nuclei, yet it remains unknown whether tau-mediated degeneration of brainstem nuclei influences cognitive impairment in prodromal Alzheimer's disease. The present study examined cognitive domains impacted in prodromal Alzheimer's disease and brainstem substructure volume in cognitively normal older adults (n = 814) and those with mild cognitive impairment (n = 542). Subsamples of cognitively normal (n = 112) and mild cognitive impairment (n = 202) also had cerebrospinal fluid Alzheimer's disease biomarker characterization. Region-of-interest and voxel-level analyses related whole brainstem, midbrain, pons, and locus coeruleus volumes to cognition with multiple linear regression models corrected for age, sex, education, apolipoprotein-ε4 carrier status, and MRI magnet strength. Within mild cognitive impairment participants, smaller midbrain and locus coeruleus volumes were significantly related to poorer performance on tests of attention and executive function, and the relationship between locus coeruleus volume and executive abilities remained significant in the mild cognitive impairment subsample with biomarker-confirmed Alzheimer's disease. A brainstem-masked voxel-wise regression further demonstrated an association between locus coeruleus volume and executive abilities. Brainstem volumes were not significantly related to memory processes. Study findings implicate midbrain and locus coeruleus volume in attention and executive deficits in mild cognitive impairment. Together with prior neuropathological studies, our data suggest a link between Alzheimer's disease-related degeneration of brainstem nuclei and cognitive deficits in prodromal Alzheimer's disease.
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Affiliation(s)
- Shubir Dutt
- Department of Psychology, University of Southern California, Los Angeles, CA, USA
- Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
| | - Yanrong Li
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA, USA
| | - Mara Mather
- Department of Psychology, University of Southern California, Los Angeles, CA, USA
- Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA
| | - Daniel A Nation
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA, USA.
- Department of Psychological Science, University of California, Irvine, Irvine, CA, USA.
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22
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Bolton CJ, Tam JW. Differential Involvement of the Locus Coeruleus in Early- and Late-Onset Alzheimer's Disease: A Potential Mechanism of Clinical Differences? MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2020:2020.11.01.20224139. [PMID: 33173930 PMCID: PMC7654926 DOI: 10.1101/2020.11.01.20224139] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Early-onset Alzheimer's disease (EOAD) has been associated with an increased likelihood of atypical clinical manifestations such as attentional impairment, yet the cause of this heterogeneity remains unclear. The locus coeruleus (LC) is implicated early in Alzheimer's disease pathology and is associated with attentional functioning. This study investigated post-mortem atrophy of the LC in EOAD and late-onset Alzheimer's disease (LOAD) in a large, well-characterized sample. Results show nearly four times greater likelihood of higher LC atrophy in EOAD as compared to LOAD after controlling for other measures of pathological progression ( p < .005). Follow-up analyses within the EOAD group revealed that compared to those who displayed mild or no LC atrophy at autopsy, those with moderate-severe atrophy of the LC displayed significantly worse performance on various baseline measures of attentional functioning ( p < .05), despite similar overall cognition ( p = .25). These findings suggest the LC is an important potential driver of clinical and pathological heterogeneity in EOAD.
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Affiliation(s)
- Corey J. Bolton
- Vanderbilt Memory & Alzheimer’s Center, Vanderbilt University Medical Center, Nashville, TN, USA
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
- Deparment of Psychiatry and Behavioral Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Joyce W. Tam
- Deparment of Psychiatry and Behavioral Sciences, Rush University Medical Center, Chicago, IL, USA
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23
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Reduced monoaminergic nuclei MRI signal detectable in pre-symptomatic older adults with future memory decline. Sci Rep 2020; 10:18707. [PMID: 33127923 PMCID: PMC7603335 DOI: 10.1038/s41598-020-71368-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Accepted: 07/10/2020] [Indexed: 12/13/2022] Open
Abstract
Evidence from murine models and human post-mortem studies indicates that monoaminergic nuclei undergo degeneration at the pre-symptomatic stage of Alzheimer’s disease (AD). Analysing 129 datasets from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) and relying on the Clinical Dementia Rating as group-defining instrument, we hypothesised that the MRI signal of monoaminergic nuclei would be a statistically significant predictor of memory decline in participants initially recruited in ADNI as healthy adults. As opposed to a group of cognitively stable participants, participants developing memory decline had reduced signal in the ventral tegmental area at baseline, before any evidence of functional decline emerged. These findings indicate that monoaminergic degeneration predates the onset of memory decline in an AD-centred initiative, with a crucial involvement of very-early changes of a dopaminergic region. This translates into potential informative avenues for pharmacological treatment of pre-symptomatic AD.
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24
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Lamerand S, Shahidehpour R, Ayala I, Gefen T, Mesulam MM, Bigio E, Geula C. Calbindin-D 28K, parvalbumin, and calretinin in young and aged human locus coeruleus. Neurobiol Aging 2020; 94:243-249. [PMID: 32663717 PMCID: PMC7483964 DOI: 10.1016/j.neurobiolaging.2020.06.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 05/19/2020] [Accepted: 06/06/2020] [Indexed: 11/16/2022]
Abstract
Certain neuronal populations, including basal forebrain cholinergic neurons (BFCN) and noradrenergic neurons of the locus coeruleus (LC), are selectively vulnerable to pathology and loss early in the course of aging and Alzheimer's disease (AD). Human BFCN show substantial loss of the calcium-binding protein (CBP), calbindin-D28K (CB), during normal aging, which is associated with formation of neurofibrillary tangles and BFCN loss in AD. Here we determined if, similar to the BFCN, LC neurons contain CB or the other 2 ubiquitous CBPs parvalbumin and calretinin, and whether these proteins display an age-related loss from LC neurons. Immunostaining for CBP and tyrosine hydroxylase, a marker of catecholaminergic neurons, was used in sections from the LC of young and aged human brains. Parvalbumin and calretinin immunoreactivities were completely absent from human LC neurons. A subpopulation of LC neurons (~10%) contained CB immunoreactivity. Quantitative analysis revealed no age-related loss of CB from LC neurons. Thus, unlike the BFCN, age-related loss of CB does not figure prominently in the selective vulnerability of LC neurons to degeneration in AD.
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Affiliation(s)
- Sydney Lamerand
- Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Ryan Shahidehpour
- Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Ivan Ayala
- Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Tamar Gefen
- Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - M-Marsel Mesulam
- Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Eileen Bigio
- Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Changiz Geula
- Mesulam Center for Cognitive Neurology and Alzheimer's Disease, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
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25
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Perez DM. α 1-Adrenergic Receptors in Neurotransmission, Synaptic Plasticity, and Cognition. Front Pharmacol 2020; 11:581098. [PMID: 33117176 PMCID: PMC7553051 DOI: 10.3389/fphar.2020.581098] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 09/11/2020] [Indexed: 12/14/2022] Open
Abstract
α1-adrenergic receptors are G-Protein Coupled Receptors that are involved in neurotransmission and regulate the sympathetic nervous system through binding and activating the neurotransmitter, norepinephrine, and the neurohormone, epinephrine. There are three α1-adrenergic receptor subtypes (α1A, α1B, α1D) that are known to play various roles in neurotransmission and cognition. They are related to two other adrenergic receptor families that also bind norepinephrine and epinephrine, the β- and α2-, each with three subtypes (β1, β2, β3, α2A, α2B, α2C). Previous studies assessing the roles of α1-adrenergic receptors in neurotransmission and cognition have been inconsistent. This was due to the use of poorly-selective ligands and many of these studies were published before the characterization of the cloned receptor subtypes and the subsequent development of animal models. With the availability of more-selective ligands and the development of animal models, a clearer picture of their role in cognition and neurotransmission can be assessed. In this review, we highlight the significant role that the α1-adrenergic receptor plays in regulating synaptic efficacy, both short and long-term synaptic plasticity, and its regulation of different types of memory. We will also present evidence that the α1-adrenergic receptors, and particularly the α1A-adrenergic receptor subtype, are a potentially good target to treat a wide variety of neurological conditions with diminished cognition.
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Affiliation(s)
- Dianne M Perez
- The Lerner Research Institute, The Cleveland Clinic Foundation, Cleveland, OH, United States
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26
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Giorgi FS, Galgani A, Puglisi-Allegra S, Limanaqi F, Busceti CL, Fornai F. Locus Coeruleus and neurovascular unit: From its role in physiology to its potential role in Alzheimer's disease pathogenesis. J Neurosci Res 2020; 98:2406-2434. [PMID: 32875628 DOI: 10.1002/jnr.24718] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 06/26/2020] [Accepted: 08/08/2020] [Indexed: 12/15/2022]
Abstract
Locus coeruleus (LC) is the main noradrenergic (NA) nucleus of the central nervous system. LC degenerates early during Alzheimer's disease (AD) and NA loss might concur to AD pathogenesis. Aside from neurons, LC terminals provide dense innervation of brain intraparenchymal arterioles/capillaries, and NA modulates astrocyte functions. The term neurovascular unit (NVU) defines the strict anatomical/functional interaction occurring between neurons, glial cells, and brain vessels. NVU plays a fundamental role in coupling the energy demand of activated brain regions with regional cerebral blood flow, it includes the blood-brain barrier (BBB), plays an active role in neuroinflammation, and participates also to the glymphatic system. NVU alteration is involved in AD pathophysiology through several mechanisms, mainly related to a relative oligoemia in activated brain regions and impairment of structural and functional BBB integrity, which contributes also to the intracerebral accumulation of insoluble amyloid. We review the existing data on the morphological features of LC-NA innervation of the NVU, as well as its contribution to neurovascular coupling and BBB proper functioning. After introducing the main experimental data linking LC with AD, which have repeatedly shown a key role of neuroinflammation and increased amyloid plaque formation, we discuss the potential mechanisms by which the loss of NVU modulation by LC might contribute to AD pathogenesis. Surprisingly, thus far not so many studies have tested directly these mechanisms in models of AD in which LC has been lesioned experimentally. Clarifying the interaction of LC with NVU in AD pathogenesis may disclose potential therapeutic targets for AD.
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Affiliation(s)
- Filippo Sean Giorgi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.,Neurology Unit, Pisa University Hospital, Pisa, Italy
| | | | | | - Fiona Limanaqi
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | | | - Francesco Fornai
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.,I.R.C.C.S. I.N.M. Neuromed, Pozzilli, Italy
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27
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Kang SS, Liu X, Ahn EH, Xiang J, Manfredsson FP, Yang X, Luo HR, Liles LC, Weinshenker D, Ye K. Norepinephrine metabolite DOPEGAL activates AEP and pathological Tau aggregation in locus coeruleus. J Clin Invest 2020; 130:422-437. [PMID: 31793911 DOI: 10.1172/jci130513] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 10/03/2019] [Indexed: 12/28/2022] Open
Abstract
Aberrant Tau inclusions in the locus coeruleus (LC) are the earliest detectable Alzheimer's disease-like (AD-like) neuropathology in the human brain. However, why LC neurons are selectively vulnerable to developing early Tau pathology and degenerating later in disease and whether the LC might seed the stereotypical spread of Tau pathology to the rest of the brain remain unclear. Here, we show that 3,4-dihydroxyphenylglycolaldehyde, which is produced exclusively in noradrenergic neurons by monoamine oxidase A metabolism of norepinephrine, activated asparagine endopeptidase that cleaved Tau at residue N368 into aggregation- and propagation-prone forms, thus leading to LC degeneration and the spread of Tau pathology. Activation of asparagine endopeptidase-cleaved Tau aggregation in vitro and in intact cells was triggered by 3,4-dihydroxyphenylglycolaldehyde, resulting in LC neurotoxicity and propagation of pathology to the forebrain. Thus, our findings reveal that norepinephrine metabolism and Tau cleavage represent the specific molecular mechanism underlying the selective vulnerability of LC neurons in AD.
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Affiliation(s)
- Seong Su Kang
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Xia Liu
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Eun Hee Ahn
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Jie Xiang
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Fredric P Manfredsson
- Translational Science and Molecular Medicine, Michigan State University, College of Human Medicine, Grand Rapids, Michigan, USA
| | - Xifei Yang
- Key Laboratory of Modern Toxicology of Shenzhen, Shenzhen Center for Disease Control and Prevention, Shenzhen, China
| | - Hongbo R Luo
- Department of Pathology and Laboratory Medicine, Harvard Medical School and Children's Hospital, Boston, Massachusetts, USA
| | - L Cameron Liles
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, USA
| | - David Weinshenker
- Department of Human Genetics, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Keqiang Ye
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
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28
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Janitzky K. Impaired Phasic Discharge of Locus Coeruleus Neurons Based on Persistent High Tonic Discharge-A New Hypothesis With Potential Implications for Neurodegenerative Diseases. Front Neurol 2020; 11:371. [PMID: 32477246 PMCID: PMC7235306 DOI: 10.3389/fneur.2020.00371] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 04/14/2020] [Indexed: 12/21/2022] Open
Abstract
The locus coeruleus (LC) is a small brainstem nucleus with widely distributed noradrenergic projections to the whole brain, and loss of LC neurons is a prominent feature of age-related neurodegenerative diseases, such as Alzheimer's disease (AD) and Parkinson's disease (PD). This article discusses the hypothesis that in early stages of neurodegenerative diseases, the discharge mode of LC neurons could be changed to a persistent high tonic discharge, which in turn might impair phasic discharge. Since phasic discharge of LC neurons is required for the release of high amounts of norepinephrine (NE) in the brain to promote anti-inflammatory and neuroprotective effects, persistent high tonic discharge of LC neurons could be a key factor in the progression of neurodegenerative diseases. Transcutaneous vagal stimulation (t-VNS), a non-invasive technique that potentially increases phasic discharge of LC neurons, could therefore provide a non-pharmacological treatment approach in specific disease stages. This article focuses on LC vulnerability in neurodegenerative diseases, discusses the hypothesis that a persistent high tonic discharge of LC neurons might affect neurodegenerative processes, and finally reflects on t-VNS as a potentially useful clinical tool in specific stages of AD and PD.
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Affiliation(s)
- Kathrin Janitzky
- Department of Neurology, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
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29
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Dyer-Reaves K, Goodman AM, Nelson AR, McMahon LL. Alpha1-Adrenergic Receptor Mediated Long-Term Depression at CA3-CA1 Synapses Can Be Induced via Accumulation of Endogenous Norepinephrine and Is Preserved Following Noradrenergic Denervation. Front Synaptic Neurosci 2019; 11:27. [PMID: 31649525 PMCID: PMC6794465 DOI: 10.3389/fnsyn.2019.00027] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2019] [Accepted: 09/20/2019] [Indexed: 12/27/2022] Open
Abstract
Locus coeruleus (LC) provides the sole source of noradrenergic (NA) innervation to hippocampus, and it undergoes significant degeneration early in Alzheimer's disease (AD). Norepinephrine (NE) modulates synaptic transmission and plasticity at hippocampal synapses which likely contributes to hippocampus-dependent learning and memory. We previously reported that pharmacological activation of α1 adrenergic receptors (α1ARs) induces long-term depression (LTD) at CA3-CA1 synapses. Here, we investigated whether accumulation of endogenous NE via pharmacological blockade of norepinephrine transporters (NETs) and the NE degradative enzyme, monoamine oxidase (MAO), can induce α1AR LTD, as these inhibitors are used clinically. Further, we sought to determine how degeneration of hippocampal NA innervation, as occurs in AD, impacts α1AR function and α1AR LTD. Bath application of NET and MAO inhibitors in slices from control rats reliably induced α1AR LTD when β adrenergic receptors were inhibited. To induce degeneration of LC-NA innervation, rats were treated with the specific NA neurotoxin DSP-4 and recordings performed 1-3 weeks later when NA axon degeneration had stabilized. Even with 85% loss of hippocampal NA innervation, α1AR LTD was successfully induced using either the α1AR agonist phenylephrine or the combined NET and MAO inhibitors, and importantly, the LTD magnitude was not different from saline-treated control. These data suggest that despite significant decreases in NA input to hippocampus, the mechanisms necessary for the induction of α1AR LTD remain functional. Furthermore, we posit that α1AR activation could be a viable therapeutic target for pharmacological intervention in AD and other diseases involving malfunctions of NA neurotransmission.
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Affiliation(s)
- Katie Dyer-Reaves
- Department of Cell, Developmental, and Integrative Biology (CDIB), School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Anthoni M. Goodman
- Department of Cell, Developmental, and Integrative Biology (CDIB), School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
- Department of Psychology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Amy R. Nelson
- Department of Cell, Developmental, and Integrative Biology (CDIB), School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Lori L. McMahon
- Department of Cell, Developmental, and Integrative Biology (CDIB), School of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
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Abstract
Noradrenergic system of brain supplies the neurotransmitter noradrenalin throughout the brain through widespread efferent projections and play pivotal role in cognitive activities and could be involve in motor and non-motor symptoms of Parkinson's disease (PD) pathology. Profound loss of noradrenergic pathways has been reported in both Parkinson's and Alzheimer's disease (AD) pathology however their employment in therapeutics is still scarce. Therefore the present review is providing the various aspects for involvement on noradrenergic pathways in PD and AD pathology as well as the imaging of locus coeruleus as indicative diagnostic marker for disease. The present review is describing about the role of tiny nucleus locus coeruleus located noradrenergic pathways in said pathologies and discussing the past research as well as lacunas in this regard.
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Affiliation(s)
- Sarika Singh
- Toxicology and Experimental Medicine Division, CDRI-CSIR, Lucknow, UP, India
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Rostral locus coeruleus integrity is associated with better memory performance in older adults. Nat Hum Behav 2019; 3:1203-1214. [PMID: 31501542 DOI: 10.1038/s41562-019-0715-2] [Citation(s) in RCA: 117] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 07/29/2019] [Indexed: 12/14/2022]
Abstract
For decades, research into memory decline in human cognitive ageing has focused on neocortical regions, the hippocampus and dopaminergic neuromodulation. Recent findings indicate that the locus coeruleus (LC) and noradrenergic neuromodulation may also play an important role in shaping memory development in later life. However, technical challenges in quantification of LC integrity have hindered the study of LC-cognition associations in humans. Using high-resolution, neuromelanin-sensitive magnetic resonance imaging, we found that individual differences in learning and memory were positively associated with LC integrity across a variety of memory tasks in both younger (n = 66) and older adults (n = 228). Moreover, we observed functionally relevant age differences confined to rostral LC. Older adults with a more 'youth-like' rostral LC also showed higher memory performance. These findings link non-invasive, in vivo indices of LC integrity to memory in ageing and highlight the role of the LC norepinephrine system in the decline of cognition.
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Weinshenker D. Long Road to Ruin: Noradrenergic Dysfunction in Neurodegenerative Disease. Trends Neurosci 2018; 41:211-223. [PMID: 29475564 PMCID: PMC5878728 DOI: 10.1016/j.tins.2018.01.010] [Citation(s) in RCA: 182] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 01/25/2018] [Accepted: 01/29/2018] [Indexed: 01/09/2023]
Abstract
It has been known for decades that degeneration of the locus coeruleus (LC), the major noradrenergic nucleus in the brain, occurs in both Alzheimer's disease (AD) and Parkinson's disease (PD), but it was given scant attention. It is now recognized that hyperphosphorylated tau in the LC is the first detectable AD-like neuropathology in the human brain, α-synuclein inclusions in the LC represent an early step in PD, and experimental LC lesions exacerbate neuropathology and cognitive/behavioral deficits in animal models. The purpose of this review is to consider the causes and consequences of LC pathology, dysfunction, and degeneration, as well as their implications for early detection and treatment.
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Affiliation(s)
- David Weinshenker
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA, USA.
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Hartner JP, Schrader LA. Interaction of Norepinephrine and Glucocorticoids Modulate Inhibition of Principle Cells of Layer II Medial Entorhinal Cortex in Male Mice. Front Synaptic Neurosci 2018; 10:3. [PMID: 29643800 PMCID: PMC5883071 DOI: 10.3389/fnsyn.2018.00003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Accepted: 03/12/2018] [Indexed: 11/13/2022] Open
Abstract
Spatial memory processing requires functional interaction between the hippocampus and the medial entorhinal cortex (MEC). The grid cells of the MEC are most abundant in layer II and rely on a complex network of local inhibitory interneurons to generate spatial firing properties. Stress can cause spatial memory deficits in males, but the specific underlying mechanisms affecting the known memory pathways remain unclear. Stress activates both the autonomic nervous system and the hypothalamic-pituitary-adrenal axis to release norepinephrine (NE) and glucocorticoids, respectively. Given that adrenergic receptor (AR) and glucocorticoid receptor (GR) expression is abundant in the MEC, both glucocorticoids and NE released in response to stress may have rapid effects on MEC-LII networks. We used whole-cell patch clamp electrophysiology in MEC slice preparations from male mice to test the effects of NE and glucocorticoids on inhibitory synaptic inputs of MEC-LII principal cells. Application of NE (100 μM) increased the frequency and amplitude of spontaneous inhibitory post-synaptic currents (sIPSCs) in approximately 75% of the principal cells tested. Unlike NE, bath application of dexamethasone (Dex, 1 μM), a synthetic glucocorticoid, or corticosterone (1 μM) the glucocorticoid in rodents, rapidly decreased the frequency of sIPSCs, but not miniature (mIPSCs) in MEC-LII principal cells. Interestingly, pre-treatment with Dex prior to NE application led to an NE-induced increase in sIPSC frequency in all cells tested. This effect was mediated by the α1-AR, as application of an α1-AR agonist, phenylephrine (PHE) yielded the same results, suggesting that a subset of cells in MEC-LII are unresponsive to α1-AR activation without prior activation of GR. We conclude that activation of GRs primes a subset of principal cells that were previously insensitive to NE to become responsive to α1-AR activation in a transcription-independent manner. These findings demonstrate the ability of stress hormones to markedly alter inhibitory signaling within MEC-LII circuits and suggest the intriguing possibility of modulation of network processing upstream of the hippocampus.
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Affiliation(s)
- Jeremiah P Hartner
- Neuroscience Program, Tulane Brain Institute, Tulane University, New Orleans, LA, United States
| | - Laura A Schrader
- Neuroscience Program, Tulane Brain Institute, Tulane University, New Orleans, LA, United States.,Department of Cell and Molecular Biology, Tulane University, New Orleans, LA, United States
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