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Butts B, Hu WT, Huang H, Kehoe PG, Miners S, Verble DD, Zetterberg H, Zhao L, Wharton W. Two year cognitive and biomarker change in a racially diverse, middle‐aged, cohort at risk for Alzheimer’s disease. Alzheimers Dement 2022. [DOI: 10.1002/alz.068100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
| | | | | | - Patrick G Kehoe
- Translational Health Sciences, Bristol Medical School, University of Bristol Bristol United Kingdom
| | | | | | - Henrik Zetterberg
- Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg Gothenburg Sweden
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2
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Butts B, Miners S, Kehoe PG, Hu WT, Huang H, Verble DD, Zetterberg H, Zhao L, Wharton W. Relationship between platelet derived growth factor receptor‐β and Alzheimer’s biomarkers in a racially diverse, high‐risk cohort. Alzheimers Dement 2021. [DOI: 10.1002/alz.057693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
| | | | | | | | | | | | - Henrik Zetterberg
- Department of Neurodegenerative Disease UCL Institute of Neurology Queen Square London United Kingdom
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3
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Abstract
COVID-19 is primarily a respiratory disease but up to two thirds of hospitalised patients show evidence of central nervous system (CNS) damage, predominantly ischaemic, in some cases haemorrhagic and occasionally encephalitic. It is unclear how much of the ischaemic damage is mediated by direct or inflammatory effects of virus on the CNS vasculature and how much is secondary to extracranial cardiorespiratory disease. Limited data suggest that the causative SARS-CoV-2 virus may enter the CNS via the nasal mucosa and olfactory fibres, or by haematogenous spread, and is capable of infecting endothelial cells, pericytes and probably neurons. Extracranially, SARS-CoV-2 targets endothelial cells and pericytes, causing endothelial cell dysfunction, vascular leakage and immune activation, sometimes leading to disseminated intravascular coagulation. It remains to be confirmed whether endothelial cells and pericytes in the cerebral vasculature are similarly targeted. Several aspects of COVID-19 are likely to impact on cognition. Cerebral white matter is particularly vulnerable to ischaemic damage in COVID-19 and is also critically important for cognitive function. There is accumulating evidence that cerebral hypoperfusion accelerates amyloid-β (Aβ) accumulation and is linked to tau and TDP-43 pathology, and by inducing phosphorylation of α-synuclein at serine-129, ischaemia may also increase the risk of development of Lewy body disease. Current therapies for COVID-19 are understandably focused on supporting respiratory function, preventing thrombosis and reducing immune activation. Since angiotensin-converting enzyme (ACE)-2 is a receptor for SARS-CoV-2, and ACE inhibitors and angiotensin receptor blockers are predicted to increase ACE-2 expression, it was initially feared that their use might exacerbate COVID-19. Recent meta-analyses have instead suggested that these medications are protective. This is perhaps because SARS-CoV-2 entry may deplete ACE-2, tipping the balance towards angiotensin II-ACE-1-mediated classical RAS activation: exacerbating hypoperfusion and promoting inflammation. It may be relevant that APOE ε4 individuals, who seem to be at increased risk of COVID-19, also have lowest ACE-2 activity. COVID-19 is likely to leave an unexpected legacy of long-term neurological complications in a significant number of survivors. Cognitive follow-up of COVID-19 patients will be important, especially in patients who develop cerebrovascular and neurological complications during the acute illness.
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Affiliation(s)
- Scott Miners
- Dementia Research Group, Bristol Medical School (THS), University of Bristol, Learning & Research level 1, Southmead Hospital, Bristol, BS10 5NB, UK.
| | - Patrick G Kehoe
- Dementia Research Group, Bristol Medical School (THS), University of Bristol, Learning & Research level 1, Southmead Hospital, Bristol, BS10 5NB, UK
| | - Seth Love
- Dementia Research Group, Bristol Medical School (THS), University of Bristol, Learning & Research level 1, Southmead Hospital, Bristol, BS10 5NB, UK.
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4
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Guzel O, Tayler HM, Skrobot OA, Miners S, Kehoe PG. The genetic association between
ACE1
and Alzheimer’s disease. Alzheimers Dement 2020. [DOI: 10.1002/alz.042822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Ozge Guzel
- University of Bristol Bristol United Kingdom
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5
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Carare RO, Aldea R, Agarwal N, Bacskai BJ, Bechman I, Boche D, Bu G, Bulters D, Clemens A, Counts SE, de Leon M, Eide PK, Fossati S, Greenberg SM, Hamel E, Hawkes CA, Koronyo‐Hamaoui M, Hainsworth AH, Holtzman D, Ihara M, Jefferson A, Kalaria RN, Kipps CM, Kanninen KM, Leinonen V, McLaurin J, Miners S, Malm T, Nicoll JAR, Piazza F, Paul G, Rich SM, Saito S, Shih A, Scholtzova H, Snyder H, Snyder P, Thormodsson FR, van Veluw SJ, Weller RO, Werring DJ, Wilcock D, Wilson MR, Zlokovic BV, Verma A. Clearance of interstitial fluid (ISF) and CSF (CLIC) group-part of Vascular Professional Interest Area (PIA): Cerebrovascular disease and the failure of elimination of Amyloid-β from the brain and retina with age and Alzheimer's disease-Opportunities for Therapy. Alzheimers Dement (Amst) 2020; 12:e12053. [PMID: 32775596 PMCID: PMC7396859 DOI: 10.1002/dad2.12053] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 05/26/2020] [Indexed: 12/22/2022]
Abstract
Two of the key functions of arteries in the brain are (1) the well-recognized supply of blood via the vascular lumen and (2) the emerging role for the arterial walls as routes for the elimination of interstitial fluid (ISF) and soluble metabolites, such as amyloid beta (Aβ), from the brain and retina. As the brain and retina possess no conventional lymphatic vessels, fluid drainage toward peripheral lymph nodes is mediated via transport along basement membranes in the walls of capillaries and arteries that form the intramural peri-arterial drainage (IPAD) system. IPAD tends to fail as arteries age but the mechanisms underlying the failure are unclear. In some people this is reflected in the accumulation of Aβ plaques in the brain in Alzheimer's disease (AD) and deposition of Aβ within artery walls as cerebral amyloid angiopathy (CAA). Knowledge of the dynamics of IPAD and why it fails with age is essential for establishing diagnostic tests for the early stages of the disease and for devising therapies that promote the clearance of Aβ in the prevention and treatment of AD and CAA. This editorial is intended to introduce the rationale that has led to the establishment of the Clearance of Interstitial Fluid (ISF) and CSF (CLIC) group, within the Vascular Professional Interest Area of the Alzheimer's Association International Society to Advance Alzheimer's Research and Treatment.
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Affiliation(s)
| | | | | | | | | | | | | | - Diederik Bulters
- University of SouthamptonSouthamptonUK
- University Hospital Southampton NHS TrustSouthamptonUK
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Christopher M. Kipps
- University of SouthamptonSouthamptonUK
- University Hospital Southampton NHS TrustSouthamptonUK
| | | | | | | | | | - Tarja Malm
- University of Eastern FinlandKuopioFinland
| | | | | | | | | | - Satoshi Saito
- National Cerebral and Cardiovascular CenterOsakaJapan
| | - Andy Shih
- Seattle Children's HospitalSeattleWashingtonUSA
| | | | | | - Peter Snyder
- University of Rhode IslandSouth KingstownRhode IslandUSA
| | | | | | | | - David J. Werring
- Stroke Research CentreUCL Queen Square Institute of NeurologyUniversity College LondonLondonUK
| | | | | | | | - Ajay Verma
- CODIAK BiosciencesCambridgeMassachusettsUSA
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6
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McFall A, Hietamies TM, Bernard A, Aimable M, Allan SM, Bath PM, Brezzo G, Carare RO, Carswell HV, Clarkson AN, Currie G, Farr TD, Fowler JH, Good M, Hainsworth AH, Hall C, Horsburgh K, Kalaria R, Kehoe P, Lawrence C, Macleod M, McColl BW, McNeilly A, Miller AA, Miners S, Mok V, O’Sullivan M, Platt B, Sena ES, Sharp M, Strangward P, Szymkowiak S, Touyz RM, Trueman RC, White C, McCabe C, Work LM, Quinn TJ. UK consensus on pre-clinical vascular cognitive impairment functional outcomes assessment: Questionnaire and workshop proceedings. J Cereb Blood Flow Metab 2020; 40:1402-1414. [PMID: 32151228 PMCID: PMC7307003 DOI: 10.1177/0271678x20910552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 11/21/2019] [Accepted: 12/06/2019] [Indexed: 11/15/2022]
Abstract
Assessment of outcome in preclinical studies of vascular cognitive impairment (VCI) is heterogenous. Through an ARUK Scottish Network supported questionnaire and workshop (mostly UK-based researchers), we aimed to determine underlying variability and what could be implemented to overcome identified challenges. Twelve UK VCI research centres were identified and invited to complete a questionnaire and attend a one-day workshop. Questionnaire responses demonstrated agreement that outcome assessments in VCI preclinical research vary by group and even those common across groups, may be performed differently. From the workshop, six themes were discussed: issues with preclinical models, reasons for choosing functional assessments, issues in interpretation of functional assessments, describing and reporting functional outcome assessments, sharing resources and expertise, and standardization of outcomes. Eight consensus points emerged demonstrating broadly that the chosen assessment should reflect the deficit being measured, and therefore that one assessment does not suit all models; guidance/standardisation on recording VCI outcome reporting is needed and that uniformity would be aided by a platform to share expertise, material, protocols and procedures thus reducing heterogeneity and so increasing potential for collaboration, comparison and replication. As a result of the workshop, UK wide consensus statements were agreed and future priorities for preclinical research identified.
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Affiliation(s)
- Aisling McFall
- Institute of Cardiovascular & Medical Sciences, College of
Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow,
UK
| | - Tuuli M Hietamies
- Institute of Cardiovascular & Medical Sciences, College of
Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow,
UK
| | - Ashton Bernard
- Institute of Cardiovascular & Medical Sciences, College of
Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow,
UK
| | - Margaux Aimable
- Centre for Discovery Brain Sciences, University of Edinburgh,
Edinburgh, UK
| | - Stuart M Allan
- Lydia Becker Institute of Immunology and Inflammation, Division
of Neuroscience and Experimental Psychology, School of Biological Sciences,
Faculty of Biology, Medicine and Health, The University of Manchester,
Manchester Academic Health Science Centre, Manchester, UK
| | - Philip M Bath
- Stroke Trials Unit, Division of Clinical Neuroscience,
University of Nottingham, Nottingham, UK
| | - Gaia Brezzo
- Centre for Discovery Brain Sciences, University of Edinburgh,
Edinburgh, UK
| | - Roxana O Carare
- Faculty of Medicine, University of Southampton, Southampton,
UK
| | - Hilary V Carswell
- University of Strathclyde, Strathclyde Institute of Pharmacy and
Biomedical Science, Glasgow, UK
| | - Andrew N Clarkson
- The Department of Anatomy, Brain Health Research Centre and
Brain Research New Zealand, University of Otago, Dunedin, New Zealand
| | - Gillian Currie
- Centre for Discovery Brain Sciences, University of Edinburgh,
Edinburgh, UK
| | - Tracy D Farr
- School of Life Sciences, University of Nottingham, Nottingham ,
UK
| | - Jill H Fowler
- Centre for Discovery Brain Sciences, University of Edinburgh,
Edinburgh, UK
| | - Mark Good
- School of Psychology, Cardiff University, Cardiff, UK
| | - Atticus H Hainsworth
- Molecular & Clinical Sciences Research Institute, St
George’s University of London, London, UK
| | - Catherine Hall
- School of Psychology, University of Sussex, Brighton, UK
| | - Karen Horsburgh
- Centre for Discovery Brain Sciences, University of Edinburgh,
Edinburgh, UK
| | - Rajesh Kalaria
- Institute of Neuroscience, Newcastle University, Newcastle Upon
Tyne, UK
| | - Patrick Kehoe
- Institute of Clinical Neurosciences, University of Bristol,
Bristol, UK
| | - Catherine Lawrence
- Lydia Becker Institute of Immunology and Inflammation, Division
of Neuroscience and Experimental Psychology, School of Biological Sciences,
Faculty of Biology, Medicine and Health, The University of Manchester,
Manchester Academic Health Science Centre, Manchester, UK
| | - Malcolm Macleod
- Centre for Clinical Brain Sciences, University of Edinburgh,
Edinburgh, UK
| | - Barry W McColl
- Centre for Discovery Brain Sciences, University of Edinburgh,
Edinburgh, UK
- UK Dementia Research Institute, Edinburgh Medical School,
University of Edinburgh, Edinburgh, UK
| | - Alison McNeilly
- School of Medicine, University of Dundee, Ninewells Hospital,
Dundee, Scotland
| | - Alyson A Miller
- Institute of Cardiovascular & Medical Sciences, College of
Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow,
UK
| | - Scott Miners
- Institute of Clinical Neurosciences, University of Bristol,
Bristol, UK
| | - Vincent Mok
- Gerald Choa Neuroscience Centre, Therese Pei Fong Chow Research
Centre for Prevention of Dementia, Division of Neurology, Department of Medicine
and Therapeutics, The Chinese University of Hong Kong, Hong Kong
| | - Michael O’Sullivan
- Faculty of Medicine, The University of Queensland, Queensland,
Australia
| | - Bettina Platt
- Institute of Medical Sciences, University of Aberdeen,
Aberdeen, Scotland
| | - Emily S Sena
- Centre for Clinical Brain Sciences, University of Edinburgh,
Edinburgh, UK
| | - Matthew Sharp
- Faculty of Medicine, University of Southampton, Southampton,
UK
| | - Patrick Strangward
- Lydia Becker Institute of Immunology and Inflammation, Division
of Neuroscience and Experimental Psychology, School of Biological Sciences,
Faculty of Biology, Medicine and Health, The University of Manchester,
Manchester Academic Health Science Centre, Manchester, UK
| | - Stefan Szymkowiak
- Centre for Discovery Brain Sciences, University of Edinburgh,
Edinburgh, UK
- UK Dementia Research Institute, Edinburgh Medical School,
University of Edinburgh, Edinburgh, UK
| | - Rhian M Touyz
- Institute of Cardiovascular & Medical Sciences, College of
Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow,
UK
| | | | - Claire White
- Lydia Becker Institute of Immunology and Inflammation, Division
of Neuroscience and Experimental Psychology, School of Biological Sciences,
Faculty of Biology, Medicine and Health, The University of Manchester,
Manchester Academic Health Science Centre, Manchester, UK
| | - Chris McCabe
- Institute of Neuroscience & Psychology, College of Medical,
Veterinary & Life Sciences, University of Glasgow, Glasgow, UK
| | - Lorraine M Work
- Institute of Cardiovascular & Medical Sciences, College of
Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow,
UK
| | - Terence J Quinn
- Institute of Cardiovascular & Medical Sciences, College of
Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow,
UK
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7
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Grimmer T, Goldhardt O, Yakushev I, Ortner M, Sorg C, Diehl-Schmid J, Förstl H, Kurz A, Perneczky R, Miners S. Associations of Neprilysin Activity in CSF with Biomarkers for Alzheimer’s Disease. NEURODEGENER DIS 2019; 19:43-50. [DOI: 10.1159/000500811] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 05/06/2019] [Indexed: 11/19/2022] Open
Abstract
Background: Neprilysin (NEP) cleaves amyloid-β 1–42 (Aβ42) in the brain. Hence, we aimed to elucidate the effect of NEP on Aβ42 in cerebrospinal fluid (CSF) and on in vivo brain amyloid load using amyloid positron emission tomography (PET) with [11C]PiB (Pittsburgh compound B). In addition, associations with the biomarkers for neuronal injury, CSF-tau and FDG-PET, were investigated. Methods: Associations were calculated using global and voxel-based (SPM8) linear regression analyses in the same cohort of 23 highly characterized Alzheimer’s disease patients. Results: CSF-NEP was significantly inversely associated with CSF-Aβ42 and positively with the extent of neuronal injury as measured by CSF-tau and FDG-PET. Conclusions: Our results on CSF-NEP are compatible with the assumption that local degradation, amongst other mechanisms of amyloid clearance, plays a role in the development of Alzheimer’s pathology. In addition, CSF-NEP is associated with the extent and the rate of neurodegeneration.
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9
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Humphreys C, Miners S, Wardlaw JM, Smith C, Love S. [P3–061]: POSTMORTEM BIOCHEMICAL ASSESSMENT OF SEVERITY AND MECHANISMS OF NEURORADIOLOGICALLY DOCUMENTED WHITE MATTER INJURY IN SMALL‐VESSEL DISEASE. Alzheimers Dement 2017. [DOI: 10.1016/j.jalz.2017.06.1271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Catherine Humphreys
- Centre for Clinical Brain SciencesUniversity of EdinburghEdinburghUnited Kingdom
| | | | | | - Colin Smith
- Univeristy of EdinburghEdinburghUnited Kingdom
| | - Seth Love
- University of BristolBristolUnited Kingdom
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10
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Mothapo KM, Stelma F, Janssen M, Kessels R, Miners S, Verbeek MM, Koopmans P, van der Ven A. Amyloid beta-42 (Aβ-42), neprilysin and cytokine levels. A pilot study in patients with HIV related cognitive impairments. J Neuroimmunol 2015; 282:73-9. [PMID: 25903731 DOI: 10.1016/j.jneuroim.2015.03.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 03/18/2015] [Accepted: 03/20/2015] [Indexed: 01/13/2023]
Abstract
HIV-associated dementia (HAD) is associated with amyloid-beta (Aβ) deposition. This study measured CSF and plasma amyloid beta-42 (Aβ-42), neprilysin (NEP) and cytokine levels in HIV-related cognitive impairments (HCI), HIV normal cognitive functioning (NF) and non-HIV controls. Our data showed a trend towards detectable plasma Aβ-42 levels more frequently in HCI (67%), when compared to NF (29%) and controls (10%). We showed elevated IL-8 levels in CSF of HCI compared to NF, although not significant values. The data from this pilot study indicates that CSF IL-8 and plasma Aβ-42 may be interesting biomarkers for the presence of HCI.
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Affiliation(s)
- K M Mothapo
- Department of Internal Medicine and Nijmegen Institute for Infection, Inflammation and Immunity, Radboud University Medical Center, The Netherlands.
| | - F Stelma
- Department of Virology, Radboud University Nijmegen Medical Center, The Netherlands
| | - M Janssen
- Department of Medical Psychology, Radboud University Nijmegen Medical Center, The Netherlands
| | - R Kessels
- Department of Medical Psychology, Radboud University Nijmegen Medical Center, The Netherlands
| | - S Miners
- Dementia Research Group, University of Bristol, Institute of Clinical Neurosciences, Level 1, Learning and Research, Southmead Hospital, Bristol, UK
| | - M M Verbeek
- Department of Neurology, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands; Department of Laboratory Medicine, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands
| | - P Koopmans
- Department of Internal Medicine and Nijmegen Institute for Infection, Inflammation and Immunity, Radboud University Medical Center, The Netherlands
| | - A van der Ven
- Department of Internal Medicine and Nijmegen Institute for Infection, Inflammation and Immunity, Radboud University Medical Center, The Netherlands
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11
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Thomas T, Miners S, Love S. Post-mortem assessment of hypoperfusion of cerebral cortex in Alzheimer's disease and vascular dementia. ACTA ACUST UNITED AC 2015; 138:1059-69. [PMID: 25688080 DOI: 10.1093/brain/awv025] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Perfusion is reduced in the cerebral neocortex in Alzheimer's disease. We have explored some of the mechanisms, by measurement of perfusion-sensitive and disease-related proteins in post-mortem tissue from Alzheimer's disease, vascular dementia and age-matched control brains. To distinguish physiological from pathological reduction in perfusion (i.e. reduction exceeding the decline in metabolic demand), we measured the concentration of vascular endothelial growth factor (VEGF), a protein induced under conditions of tissue hypoxia through the actions of hypoxia-inducible factors, and the myelin associated glycoprotein to proteolipid protein 1 (MAG:PLP1) ratio, which declines in chronically hypoperfused brain tissue. To evaluate possible mechanisms of hypoperfusion, we also measured the levels of amyloid-β40, amyloid-β42, von Willebrand factor (VWF; a measure of microvascular density) and the potent vasoconstrictor endothelin 1 (EDN1); we assayed the activity of angiotensin I converting enzyme (ACE), which catalyses the production of another potent vasoconstrictor, angiotensin II; and we scored the severity of arteriolosclerotic small vessel disease and cerebral amyloid angiopathy, and determined the Braak tangle stage. VEGF was markedly increased in frontal and parahippocampal cortex in Alzheimer's disease but only slightly and not significantly in vascular dementia. In frontal cortex the MAG:PLP1 ratio was significantly reduced in Alzheimer's disease and even more so in vascular dementia. VEGF but not MAG:PLP1 increased with Alzheimer's disease severity, as measured by Braak tangle stage, and correlated with amyloid-β42 and amyloid-β42: amyloid-β40 but not amyloid-β40. Although MAG:PLP1 tended to be lowest in cortex from patients with severe small vessel disease or cerebral amyloid angiopathy, neither VEGF nor MAG:PLP1 correlated significantly with the severity of structural vascular pathology (small vessel disease, cerebral amyloid angiopathy or VWF). However, MAG:PLP1 showed a significant negative correlation with the level of EDN1, which we previously showed to be elevated in the cerebral cortex Alzheimer's disease. These finding are in contrast with the previously demonstrated reduction in EDN1, and positive correlation with MAG:PLP1, in the hypoperfused white matter in Alzheimer's disease. The decline in MAG:PLP1 strongly suggests pathological hypoperfusion of the frontal cortex in Alzheimer's disease. Although severe small vessel disease or cerebral amyloid angiopathy may contribute in some cases, abnormal vascular contractility mediated by EDN1 is likely to be a more important overall contributor. Both amyloid-β accumulation and hypoperfusion are likely to cause the upregulation of VEGF.
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Affiliation(s)
- Taya Thomas
- Dementia Research Group, University of Bristol, Learning & Research level 1, Southmead Hospital, Bristol BS10 5NB, UK
| | - Scott Miners
- Dementia Research Group, University of Bristol, Learning & Research level 1, Southmead Hospital, Bristol BS10 5NB, UK
| | - Seth Love
- Dementia Research Group, University of Bristol, Learning & Research level 1, Southmead Hospital, Bristol BS10 5NB, UK
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12
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Miners S, Moulding H, de Silva R, Love S. Reduced vascular endothelial growth factor and capillary density in the occipital cortex in dementia with Lewy bodies. Brain Pathol 2014; 24:334-43. [PMID: 24521289 DOI: 10.1111/bpa.12130] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Accepted: 02/02/2014] [Indexed: 01/30/2023] Open
Abstract
In dementia with Lewy bodies (DLB), blood flow tends to be reduced in the occipital cortex. We previously showed elevated activity of the endothelin and angiotensin pathways in Alzheimer's disease (AD). We have measured endothelin-1 (ET-1) level and angiotensin-converting enzyme (ACE) activity in the occipital cortex in DLB and control brains. We also measured vascular endothelial growth factor (VEGF); factor VIII-related antigen (FVIIIRA) to indicate microvessel density; myelin-associated glycoprotein (MAG), a marker of ante-mortem hypoperfusion; total α-synuclein (α-syn) and α-synuclein phosphorylated at Ser129 (α-syn-p129). In contrast to findings in AD, ACE activity and ET-1 level were unchanged in DLB compared with controls. VEGF and FVIIIRA levels were, however, significantly lower in DLB. VEGF correlated positively with MAG concentration (in keeping with a relationship between reduction in VEGF and hypoperfusion), and negatively with α-syn and α-syn-p129 levels. Both α-syn and α-syn-p129 levels increased in human SH-SY5Y neuroblastoma cells after oxygen-glucose deprivation (OGD), and VEGF level was reduced in SH-SY5Y cells overexpressing α-syn. Taken together, our findings suggest that reduced microvessel density rather than vasoconstriction is responsible for lower occipital blood flow in DLB, and that the loss of microvessels may result from VEGF deficiency, possible secondary to the accumulation of α-syn.
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Affiliation(s)
- Scott Miners
- Dementia Research Group, Institute of Clinical Neurosciences, School of Clinical Sciences, University of Bristol, Bristol, UK
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13
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Grimmer T, Goldhardt O, Förster S, Drzezga A, Förstl H, Kurz A, Miners S. P4–348: Neprilysin activity in CSF is associated with CSF tau but neither with cerebral amyloid load nor CSF amyloid 1–42 in Alzheimer's disease. Alzheimers Dement 2013. [DOI: 10.1016/j.jalz.2013.08.182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
| | | | | | | | - Hans Förstl
- Technische Universitaet Muenchen Munich Germany
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14
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Miners S, van Helmond Z, Barker R, Passmore PA, Johnston JA, Todd S, McGuinness BM, Panza F, Seripa D, Solfrizzi V, Love S, Prince JA, Kehoe PG. Genetic variation in MME in relation to neprilysin protein and enzyme activity, Aβ levels, and Alzheimer's disease risk. Int J Mol Epidemiol Genet 2012; 3:30-38. [PMID: 22493749 PMCID: PMC3316445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Accepted: 12/12/2011] [Indexed: 05/31/2023]
Abstract
Neprilysin (NEP), also known as membrane metalloendopeptidase (MME), is considered amongst the most important β-amyloid (Aβ)-degrading enzymes with regard to prevention of Alzheimer's disease (AD) pathology. Variation in the NEP gene (MME) has been suggested as a risk factor for AD. We conducted a genetic association study of 7MME SNPs - rs1836914, rs989692, rs9827586, rs6797911, rs61760379, rs3736187, rs701109 - with respect to AD risk in a cohort of 1057 probable and confirmed AD cases and 424 age-matched non-demented controls from the United Kingdom, Italy and Sweden. We also examined the association of these MME SNPs with NEP protein level and enzyme activity, and on biochemical measures of Aβ accumulation in frontal cortex - levels of total soluble Aβ, oligomeric Aβ(1-42), and guanidine-extractable (insoluble) Aβ - in a sub-group of AD and control cases with post-mortem brain tissue. On multivariate logistic regression analysis one of the MME variants (rs6797911) was associated with AD risk (P = 0.00052, Odds Ratio (O.R. = 1.40, 95% confidence interval (1.16-1.70)). None of the SNPs had any association with Aβ levels; however, rs9827586 was significantly associated with NEP protein level (p=0.014) and enzyme activity (p=0.006). Association was also found between rs701109 and NEP protein level (p=0.026) and a marginally non-significant association was found for rs989692 (p=0.055). These data suggest that MME variation may be associated with AD risk but we have not found evidence that this is mediated through modification of NEP protein level or activity.
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Affiliation(s)
- Scott Miners
- Dementia Research Group, University of Bristol, Institute of Clinical Neurosciences, Frenchay HospitalBristol, UK
| | - Zoë van Helmond
- Dementia Research Group, University of Bristol, Institute of Clinical Neurosciences, Frenchay HospitalBristol, UK
| | - Rachel Barker
- Dementia Research Group, University of Bristol, Institute of Clinical Neurosciences, Frenchay HospitalBristol, UK
| | - Peter A Passmore
- Department of Geriatric Medicine, The Queen’s University of BelfastBelfast, UK
| | - Janet A Johnston
- Department of Geriatric Medicine, The Queen’s University of BelfastBelfast, UK
| | - Stephen Todd
- Department of Geriatric Medicine, The Queen’s University of BelfastBelfast, UK
| | | | - Francesco Panza
- Department of Geriatrics, Center for Aging Brain, Memory Unit, University of BariBari, Italy
- Geriatric Unit and Gerontology-Geriatrics Research Laboratory, Department of Medical Sciences, IRCCS, Casa Sollievo della Sofferenza, San Giovanni RotondoFoggia, Italy
| | - Davide Seripa
- Geriatric Unit and Gerontology-Geriatrics Research Laboratory, Department of Medical Sciences, IRCCS, Casa Sollievo della Sofferenza, San Giovanni RotondoFoggia, Italy
| | - Vincenzo Solfrizzi
- Department of Geriatrics, Center for Aging Brain, Memory Unit, University of BariBari, Italy
| | - Seth Love
- Dementia Research Group, University of Bristol, Institute of Clinical Neurosciences, Frenchay HospitalBristol, UK
| | - Jonathan A Prince
- Center for Genomics and Bioinformatics, Karolinska InstituteStockholm, Sweden
| | - Patrick G Kehoe
- Dementia Research Group, University of Bristol, Institute of Clinical Neurosciences, Frenchay HospitalBristol, UK
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15
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Kehoe PG, Miners S, Love S. Angiotensins in Alzheimer's disease - friend or foe? Trends Neurosci 2009; 32:619-28. [PMID: 19796831 DOI: 10.1016/j.tins.2009.07.006] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2009] [Revised: 07/22/2009] [Accepted: 07/28/2009] [Indexed: 11/28/2022]
Abstract
The renin-angiotensin system (RAS) is an important regulator of blood pressure. Observational and experimental studies suggest that alterations in blood pressure and components of the brain RAS contribute to the development and progression of Alzheimer's disease (AD), resulting in changes that can lead or contribute to cognitive decline. The complexity of the RAS and diversity of its interactions with neurological processes have recently become apparent but large gaps in our understanding still remain. Modulation of activity of components of the brain RAS offers substantial opportunities for the treatment and prevention of dementia, including AD. This paper reviews molecular, genetic, experimental and clinical data as well as the therapeutic opportunities that relate to the involvement of the RAS in AD.
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Affiliation(s)
- Patrick G Kehoe
- Dementia Research Group, Institute of Clinical Neurosciences, Department of Clinical Science at North Bristol, University of Bristol, Frenchay Hospital, Bristol BS16 1LE, UK.
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16
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Miners S, Ashby E, Baig S, Harrison R, Tayler H, Speedy E, Prince JA, Love S, Kehoe PG. Angiotensin-converting enzyme levels and activity in Alzheimer's disease: differences in brain and CSF ACE and association with ACE1 genotypes. Am J Transl Res 2009; 1:163-77. [PMID: 19956428 PMCID: PMC2776311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2008] [Accepted: 01/12/2009] [Indexed: 05/28/2023]
Abstract
Angiotensin-converting enzyme (ACE) has been implicated in Alzheimer's disease (AD): ACE1 variations influence plasma ACE and risk of AD, and ACE is increased in AD brain. We measured frontal ACE level and activity in 89 AD and 51 control brains, and post-mortem CSF from 101 cases and 19 controls. Neuron-specific enolase (NSE) level and Braak stage were used to indicate neuronal preservation and disease progression. We genotyped the common ACE insertion/deletion polymorphism, rs4343, rs1800764 and rs4921. ACE activity was elevated in AD and correlated with Braak stage. Crude ACE levels were unchanged but adjustment for NSE suggested increased neuronal ACE production with Braak stage. Exposing SH-SY-5Y neurons to oligomeric Abeta1-42 increased ACE level and activity, suggesting Abeta may upregulate ACE in AD. In CSF, ACE level but not activity was reduced in AD. ACE1 genotype did not predict ACE level or activity in brain or CSF. ACE activity and neuronal production increase in AD brain, possibly in response to Abeta. Peripheral measurements do not reflect ACE activity in the brain.
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Affiliation(s)
- Scott Miners
- From Dementia Research Group, Institute of Clinical Neurosciences, Clinical Science at North Bristol, University of Bristol, Frenchay HospitalFrenchay, Bristol BS16 1LE, UK
| | - Emma Ashby
- From Dementia Research Group, Institute of Clinical Neurosciences, Clinical Science at North Bristol, University of Bristol, Frenchay HospitalFrenchay, Bristol BS16 1LE, UK
| | - Shabnam Baig
- From Dementia Research Group, Institute of Clinical Neurosciences, Clinical Science at North Bristol, University of Bristol, Frenchay HospitalFrenchay, Bristol BS16 1LE, UK
| | - Rachel Harrison
- From Dementia Research Group, Institute of Clinical Neurosciences, Clinical Science at North Bristol, University of Bristol, Frenchay HospitalFrenchay, Bristol BS16 1LE, UK
| | - Hannah Tayler
- From Dementia Research Group, Institute of Clinical Neurosciences, Clinical Science at North Bristol, University of Bristol, Frenchay HospitalFrenchay, Bristol BS16 1LE, UK
| | - Elizabeth Speedy
- From Dementia Research Group, Institute of Clinical Neurosciences, Clinical Science at North Bristol, University of Bristol, Frenchay HospitalFrenchay, Bristol BS16 1LE, UK
| | - Jonathan A Prince
- Department of Medical Epidemiology and Biostatistics, Karolinska Institute177 77 Stockholm, Sweden
| | - Seth Love
- From Dementia Research Group, Institute of Clinical Neurosciences, Clinical Science at North Bristol, University of Bristol, Frenchay HospitalFrenchay, Bristol BS16 1LE, UK
| | - Patrick G Kehoe
- From Dementia Research Group, Institute of Clinical Neurosciences, Clinical Science at North Bristol, University of Bristol, Frenchay HospitalFrenchay, Bristol BS16 1LE, UK
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17
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Miners S. Comments on the nature of prayer research. Altern Ther Health Med 1997; 3:19-20, 22. [PMID: 9210771] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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