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Liu D, Hsueh SC, Tweedie D, Price N, Glotfelty E, Lecca D, Telljohann R, deCabo R, Hoffer BJ, Greig NH. Chronic inflammation with microglia senescence at basal forebrain: impact on cholinergic deficit in Alzheimer's brain haemodynamics. Brain Commun 2024; 6:fcae204. [PMID: 38978722 PMCID: PMC11228546 DOI: 10.1093/braincomms/fcae204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 04/23/2024] [Accepted: 06/11/2024] [Indexed: 07/10/2024] Open
Abstract
Cholinergic innervation in the brain is involved in modulating neurovascular function including cerebral blood flow haemodynamics in response to neuronal activity. Cholinergic deficit is associated with pathophysiology in Alzheimer's disease, albeit the aetiology remains to be clarified. In the current study, neocortex cerebral blood flow response to acetylcholine was evaluated by Laser-Doppler Flowmetry (LDF) in 3xTgAD Alzheimer's disease model) and wild-type mice of two age groups. The peak of cerebral blood flow to acetylcholine (i.v.) from baseline levels (% ΔrCBF) was higher in young 3xTgAD versus in wild-type mice (48.35; 95% CI:27.03-69.67 versus 22.70; CI:15.5-29.91, P < 0.05); this was reversed in old 3xTgAD mice (21.44; CI:2.52-40.35 versus 23.25; CI:23.25-39). Choline acetyltransferase protein was reduced in neocortex, while cerebrovascular reactivity to acetylcholine was preserved in young 3×TgAD mice. This suggests endogenous acetylcholine deficit and possible cholinergic denervation from selected cholinergic nuclei within the basal forebrain. The early deposition of tauopathy moieties (mutant hTau and pTau181) and its coincidence in cholinergic cell clusters (occasionaly), were observed at the basal forebrain of 3xTgAD mice including substantia innominate, nucleus Basalis of Meynert and nucleus of horizontal limb diagonal band of Broca. A prominent feature was microglia interacting tauopathy and demonstrated a variety of morphology changes particularly when located in proximity to tauopathy. The microglia ramified phenotype was reduced as evaluated by the ramification index and Fractal analysis. Increased microglia senescence, identified as SASP (senescence-associated secretory phenotype), was colocalization with p16Ink4ɑ, a marker of irreversible cell-cycle arrest in old 3xTgAD versus wild-type mice (P = 0.001). The p16Ink4ɑ was also observed in neuronal cells bearing tauopathy within the basal forebrain of 3xTgAD mice. TNF-ɑ, the pro-inflammatory cytokine elevated persistently in microglia (Pearson's correlation coefficient = 0.62) and the loss of cholinergic cells in vulnerable basal forebrain environment, was indicated by image analysis in 3xTgAD mice, which linked to the cholinergic deficits in neocortex rCBF haemodynamics. Our study revealed the early change of CBF haemodynamics to acetylcholine in 3xTgAD model. As a major effector of brain innate immune activation, microglia SASP with age-related disease progression is indicative of immune cell senescence, which contributes to chronic inflammation and cholinergic deficits at the basal forebrain. Targeting neuroinflammation and senescence may mitigate cholinergic pathophysiology in Alzheimer's disease.
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Affiliation(s)
- Dong Liu
- Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Shih Chang Hsueh
- Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
- Department of Pediatrics, Columbia University Irving Medical Center, Columbia University Vagelos Physicians & Surgeons College of Medicine, New York City, NY 10032, USA
| | - David Tweedie
- Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Nate Price
- Experimental Gerontology Section, Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Elliot Glotfelty
- Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
- Department of Neuroscience, Karolinska Institute, Stockholm 17177, Sweden
- Cellular Stress and Inflammation Section, Intramural Research Program, National Institute on Drug Abuse, Baltimore, MD 21224, USA
| | - Daniela Lecca
- Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
- Shock, Trauma & Anesthesiology Research Center, University of Maryland, Baltimore, MD 21201, USA
| | - Richard Telljohann
- Laboratory of Cardiovascular Science, Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Rafael deCabo
- Department of Pediatrics, Columbia University Irving Medical Center, Columbia University Vagelos Physicians & Surgeons College of Medicine, New York City, NY 10032, USA
| | - Barry J Hoffer
- Department of Neurosurgery, Case Western Reserve University School of Medicine, University Hospitals, Cleveland, OH 44106, USA
| | - Nigel H Greig
- Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
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2
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Moyaert P, Beun S, Achten E, Clement P. Effect of Acetylcholinesterase Inhibitors on Cerebral Perfusion and Cognition: A Systematic Review. J Alzheimers Dis 2023:JAD221125. [PMID: 37182871 DOI: 10.3233/jad-221125] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
BACKGROUND Perfusion imaging has the potential to identify neurodegenerative disorders in a preclinical stage. However, to correctly interpret perfusion-derived parameters, the impact of perfusion modifiers should be evaluated. OBJECTIVE In this systematic review, the impact of acute and chronic intake of four acetylcholinesterase inhibitors (AChEIs) on cerebral perfusion in adults was investigated: physostigmine, donepezil, galantamine, and rivastigmine. RESULTS Chronic AChEI treatment results in an increase of cerebral perfusion in treatment-responsive patients with Alzheimer's disease, dementia with Lewy bodies, and Parkinson's disease dementia in the frontal, parietal, temporal, and occipital lobes, as well as the cingulate gyrus. These effects appear to be temporary, dose-related, and consistent across populations and different AChEI types. On the contrary, further perfusion decline was reported in patients not receiving AChEIs or not responding to the treatment. CONCLUSION AChEIs appear to be a potential perfusion modifier in neurodegenerative patients. More research focused on quantitative perfusion in both patients with and without a cholinergic deficit is needed to draw conclusions on whether AChEI intake should be considered when analyzing perfusion data.
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Affiliation(s)
- Paulien Moyaert
- Department of Diagnostic Sciences, Ghent University, Ghent, Belgium
- Lawson Health Research Institute, London, Ontario, Canada
| | - Soetkin Beun
- Department of Diagnostic Sciences, Ghent University, Ghent, Belgium
| | - Eric Achten
- Department of Diagnostic Sciences, Ghent University, Ghent, Belgium
| | - Patricia Clement
- Department of Diagnostic Sciences, Ghent University, Ghent, Belgium
- Department of Medical Imaging, Ghent University Hospital, Ghent, Belgium
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3
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Weijs RWJ, Shkredova DA, Brekelmans ACM, Thijssen DHJ, Claassen JAHR. Longitudinal changes in cerebral blood flow and their relation with cognitive decline in patients with dementia: Current knowledge and future directions. Alzheimers Dement 2023; 19:532-548. [PMID: 35485906 DOI: 10.1002/alz.12666] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 02/24/2022] [Accepted: 02/28/2022] [Indexed: 01/15/2023]
Abstract
The pathophysiology underlying cognitive decline is multifactorial, with increasing literature suggesting a role for cerebrovascular health. Cerebral blood flow (CBF) is an important element of cerebrovascular health, which raises questions regarding the relation between CBF and cognitive decline. Cross-sectional studies demonstrate lower CBF in patients with cognitive decline compared to healthy age-matched peers. Remarkably, longitudinal studies do not support a link between CBF reductions and cognitive decline. These studies, however, are often limited by small sample sizes and may therefore be underpowered to detect small effect sizes. Therefore, through a systematic review and meta-analysis of longitudinal studies, we examined whether longitudinal changes in global CBF are related to cognitive decline in subjects with Alzheimer's disease, and qualitatively described findings on regional CBF. Considering the growing impact of dementia and the lack of treatment options, it is important to understand the role of CBF as a prognostic biomarker and/or treatment target in dementia.
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Affiliation(s)
- Ralf W J Weijs
- Department of Physiology, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Daria A Shkredova
- Department of Physiology, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, the Netherlands.,Centre for Heart, Lung, and Vascular Health, School of Health and Exercise Sciences, University of British Columbia Okanagan, Kelowna, British Columbia, Canada
| | - Anna C M Brekelmans
- Department of Physiology, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Dick H J Thijssen
- Department of Physiology, Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, the Netherlands.,Research Institute for Sport and Exercise Science, Liverpool John Moores University, Liverpool, UK
| | - Jurgen A H R Claassen
- Department of Geriatrics, Radboud UMC Alzheimer's Center, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, the Netherlands
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4
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Chavushyan VA, Simonyan KV, Danielyan MH, Avetisyan LG, Darbinyan LV, Isoyan AS, Lorikyan AG, Hovhannisyan LE, Babakhanyan MA, Sukiasyan LM. Pathology and prevention of brain microvascular and neuronal dysfunction induced by a high-fructose diet in rats. Metab Brain Dis 2023; 38:269-286. [PMID: 36271967 DOI: 10.1007/s11011-022-01098-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 10/08/2022] [Indexed: 02/03/2023]
Abstract
A high-fructose diet causes metabolic abnormalities in rats, and the cluster of complications points to microvascular and neuronal disorders of the brain. The aim of this study was to evaluate i) the involvement of microvascular disorders and neuronal plasticity in the deleterious effects of a high-fructose diet on the rat brain and ii) a comparative assessment of the effectiveness of Phytocollection therapy (with antidiabetic, antioxidant, and acetylcholinesterase inhibitory activities) compared to Galantamine as first-line therapy for dementia and Diabeton as first-line therapy for hyperglycemia. The calcium adenosine triphosphate non-injection histoangiological method was used to assess capillary network diameter and density. A high-fructose diet resulted in a significant decrease in the diameter and density of the capillary bed, and pharmacological manipulations had a modulatory effect on microcirculatory adaptive mechanisms. In vivo single-unit extracellular recording was used to investigate short-term plasticity in the medial prefrontal cortex. Differences in the parameters of spike background activity and expression of excitatory and inhibitory responses of cortical neurons have been discovered, allowing for flexibility and neuronal function stabilization in pathology and pharmacological prevention. Integration of the coupling mechanism between microvascular function and neuronal spike activity could delay the progressive decline in cognitive function in rats fed a high fructose diet.
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Affiliation(s)
- V A Chavushyan
- Neuroendocrine Relationships Lab, Orbeli Institute of Physiology NAS RA, 0028, Yerevan, Armenia
| | - K V Simonyan
- Neuroendocrine Relationships Lab, Orbeli Institute of Physiology NAS RA, 0028, Yerevan, Armenia.
| | - M H Danielyan
- Histochemistry and Electron Microscopy Lab, Orbeli Institute of Physiology NAS RA, 0028, Yerevan, Armenia
| | - L G Avetisyan
- Neuroendocrine Relationships Lab, Orbeli Institute of Physiology NAS RA, 0028, Yerevan, Armenia
| | - L V Darbinyan
- Sensorimotor Integration Lab, Orbeli Institute of Physiology NAS RA, 0028, Yerevan, Armenia
| | - A S Isoyan
- Neuroendocrine Relationships Lab, Orbeli Institute of Physiology NAS RA, 0028, Yerevan, Armenia
| | - A G Lorikyan
- Neuroendocrine Relationships Lab, Orbeli Institute of Physiology NAS RA, 0028, Yerevan, Armenia
| | - L E Hovhannisyan
- G.S. Davtyan Institute of Hydroponics Problems NAS RA, 0082, Yerevan, Armenia
| | - M A Babakhanyan
- G.S. Davtyan Institute of Hydroponics Problems NAS RA, 0082, Yerevan, Armenia
| | - L M Sukiasyan
- Neuroendocrine Relationships Lab, Orbeli Institute of Physiology NAS RA, 0028, Yerevan, Armenia
- Yerevan State Medical University After M. Heratsi, 0025, Yerevan, Armenia
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5
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The role of the autonomic nervous system in cerebral blood flow regulation in dementia: A review. Auton Neurosci 2022; 240:102985. [DOI: 10.1016/j.autneu.2022.102985] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 02/28/2022] [Accepted: 04/28/2022] [Indexed: 11/19/2022]
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6
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Leijenaar JF, Ingala S, Sudre CH, Mutsaerts HJMM, Leeuwis AE, van der Flier WM, Scheltens P, Weinstein HC, Barkhof F, van Gerven J, Groeneveld GJ, Prins ND. Decreased integrity of the monoaminergic tract is associated with a positive response to MPH in patients with vascular cognitive impairment - proof of principle study STREAM-VCI. CEREBRAL CIRCULATION - COGNITION AND BEHAVIOR 2022; 3:100128. [PMID: 36324417 PMCID: PMC9616323 DOI: 10.1016/j.cccb.2022.100128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Revised: 01/30/2022] [Accepted: 02/21/2022] [Indexed: 11/22/2022]
Abstract
Background Patients with vascular cognitive impairment (VCI) are very heterogeneous in both symptoms and type of cerebrovascular pathology. This might be an important reason why there is no symptomatic treatment available for VCI patients. In this study, we investigated in patients with VCI, whether there was an association between a positive response to methylphenidate and galantamine and the type of cerebrovascular disease, structural damage to specific neurotransmitter systems, cerebral perfusion, and presence of co-morbid Alzheimer (AD) pathology. Methods We included 27 VCI patients (mean age 67 years ± 8,30% female) from the STREAM-VCI trial who received placebo, methylphenidate(10 mg), and galantamine(16 mg) in a single challenge, cross-over design. In this study, we classified patients improving on a task for executive functioning after methylphenidate compared to placebo as methylphenidate responders (MPH+; resp. non-responders, MPH-) and patients improving on a task for memory after galantamine compared to placebo as galantamine responders (GAL+; resp. non-responders, GAL-). On baseline MRI, we visually assessed measures of cerebrovascular disease, automatically segmented white matter hyperintensities, used diffusion tensor imaging to visualize the integrity of monoaminergic and cholinergic neurotransmitter systems with mean diffusivity (MD) and fractional anisotropy (FA). Comorbid AD pathology was assessed using CSF or amyloid-PET. We tested differences between responders and non-responders using ANOVA, adjusting for age and sex. Results Nine patients were MPH+ vs 18 MPH-. MPH+ had higher MD (1.22 ± 0.07 vs 0.94 ± 0.05); p = .001) and lower FA (0.38 ± .01 vs 0.43 ± .01); p = .04) in the monoaminergic tract compared to MPH-. Eight patients were GAL+ and 18 GAL-. We found no differences between GAL+ and GAL- in any of the MRI measures. Information on co-morbid AD pathology was present in 17 patients. AD pathology tended to be more frequent in GAL+ vs GAL- (5(71%) vs 2(20%); p = .06). Conclusions In patients with VCI, we found that decreased integrity of the monoaminergic tract is associated with a positive response to MPH. Responsiveness to galantamine may be related to co-morbid AD pathology.
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Affiliation(s)
- Jolene F Leijenaar
- Alzheimer Center & Department of Neurology, Amsterdam Neuroscience, VU University Medical Center, Amsterdam UMC Locatie VUmc, Amsterdam, the Netherland
| | - Silvia Ingala
- Department of Radiology and Nuclear Medicine, Amsterdam Neuroscience, VU University Medical Center, Amsterdam UMC, Amsterdam, the Netherland
| | - Carole H Sudre
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
- Dementia Research Centre, Institute of Neurology, University College London, London, United Kingdom
| | - Henk-Jan MM Mutsaerts
- Department of Radiology and Nuclear Medicine, Amsterdam Neuroscience, VU University Medical Center, Amsterdam UMC, Amsterdam, the Netherland
- Department of Radiology and Nuclear Medicine, University Hospital Ghent, Ghent, Belgium
| | - Anna E. Leeuwis
- Alzheimer Center & Department of Neurology, Amsterdam Neuroscience, VU University Medical Center, Amsterdam UMC Locatie VUmc, Amsterdam, the Netherland
| | - Wiesje M van der Flier
- Alzheimer Center & Department of Neurology, Amsterdam Neuroscience, VU University Medical Center, Amsterdam UMC Locatie VUmc, Amsterdam, the Netherland
- Department of Epidemiology, Amsterdam Neuroscience, VU University Medical Center, Amsterdam UMC, Amsterdam, the Netherland
| | - Philip Scheltens
- Alzheimer Center & Department of Neurology, Amsterdam Neuroscience, VU University Medical Center, Amsterdam UMC Locatie VUmc, Amsterdam, the Netherland
| | - Henry C Weinstein
- Department of Neurology, Onze Lieve Vrouwe Gasthuis West, Amsterdam, the Netherland
| | - Frederik Barkhof
- Department of Radiology and Nuclear Medicine, Amsterdam Neuroscience, VU University Medical Center, Amsterdam UMC, Amsterdam, the Netherland
- Institutes of Neurology and Healthcare Engineering, UCL, London, United Kingdom
| | | | - Geert Jan Groeneveld
- Centre for Human Drug Research, Leiden, the Netherland
- Department of Anesthesiology, Leiden University Medical Center, Leiden, the Netherland
| | - Niels D Prins
- Alzheimer Center & Department of Neurology, Amsterdam Neuroscience, VU University Medical Center, Amsterdam UMC Locatie VUmc, Amsterdam, the Netherland
- Brain Research Center, Amsterdam, the Netherland
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7
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Wakisaka Y, Matsuo R, Nakamura K, Ago T, Kamouchi M, Kitazono T. Pre-Stroke Cholinesterase Inhibitor Treatment Is Beneficially Associated with Functional Outcome in Patients with Acute Ischemic Stroke and Pre-Stroke Dementia: The Fukuoka Stroke Registry. Cerebrovasc Dis 2021; 50:390-396. [PMID: 33744892 DOI: 10.1159/000514368] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Accepted: 01/02/2021] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION Pre-stroke dementia is significantly associated with poor stroke outcome. Cholinesterase inhibitors (ChEIs) might reduce the risk of stroke in patients with dementia. However, the association between pre-stroke ChEI treatment and stroke outcome remains unresolved. Therefore, we aimed to determine this association in patients with acute ischemic stroke and pre-stroke dementia. METHODS We enrolled 805 patients with pre-stroke dementia among 13,167 with ischemic stroke within 7 days of onset who were registered in the Fukuoka Stroke Registry between June 2007 and May 2019 and were independent in basic activities of daily living (ADLs) before admission. Primary and secondary study outcomes were poor functional outcome (modified Rankin Scale [mRS] score: 3-6) at 3 months after stroke onset and neurological deterioration (≥2-point increase in the NIH Stroke Scale [NIHSS] during hospitalization), respectively. Logistic regression analysis was used to evaluate associations between pre-stroke ChEI treatment and study outcomes. To improve covariate imbalance, we further conducted a propensity score (PS)-matched cohort study. RESULTS Among the participants, 212 (26.3%) had pre-stroke ChEI treatment. Treatment was negatively associated with poor functional outcome (odds ratio: 0.68 [95% confidence interval: 0.46-0.99]) and neurological deterioration (0.52 [0.31-0.88]) after adjusting for potential confounding factors. In the PS-matched cohort study, the same trends were observed between pre-stroke ChEI treatment and poor functional outcome (0.61 [0.40-0.92]) and between the treatment and neurological deterioration (0.47 [0.25-0.86]). CONCLUSIONS Our findings suggest that pre-stroke ChEI treatment is associated with reduced risks for poor functional outcome and neurological deterioration after acute ischemic stroke in patients with pre-stroke dementia who are independent in basic ADLs before the onset of stroke.
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Affiliation(s)
- Yoshinobu Wakisaka
- Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan,
| | - Ryu Matsuo
- Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.,Department of Health Care Administration and Management, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.,Center for Cohort Studies, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Kuniyuki Nakamura
- Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Tetsuro Ago
- Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Masahiro Kamouchi
- Department of Health Care Administration and Management, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.,Center for Cohort Studies, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Takanari Kitazono
- Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.,Center for Cohort Studies, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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8
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Kuang H, Zhou ZF, Zhu YG, Wan ZK, Yang MW, Hong FF, Yang SL. Pharmacological Treatment of Vascular Dementia: A Molecular Mechanism Perspective. Aging Dis 2021; 12:308-326. [PMID: 33532143 PMCID: PMC7801279 DOI: 10.14336/ad.2020.0427] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 04/27/2020] [Indexed: 11/01/2022] Open
Abstract
Vascular dementia (VaD) is a neurodegenerative disease, with cognitive dysfunction attributable to cerebrovascular factors. At present, it is the second most frequently occurring type of dementia in older adults (after Alzheimer's disease). The underlying etiology of VaD has not been completely elucidated, which limits its management. Currently, there are no approved standard treatments for VaD. The drugs used in VaD are only suitable for symptomatic treatment and cannot prevent or reduce the occurrence and progression of VaD. This review summarizes the current status of pharmacological treatment for VaD, from the perspective of the molecular mechanisms specified in various pathogenic hypotheses, including oxidative stress, the central cholinergic system, neuroinflammation, neuronal apoptosis, and synaptic plasticity. As VaD is a chronic cerebrovascular disease with multifactorial etiology, combined therapy, targeting multiple pathophysiological factors, may be the future trend in VaD.
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Affiliation(s)
- Huang Kuang
- 1Department of Physiology, College of Medicine, Nanchang University, Nanchang, China
| | - Zhi-Feng Zhou
- 1Department of Physiology, College of Medicine, Nanchang University, Nanchang, China
| | - Yu-Ge Zhu
- 1Department of Physiology, College of Medicine, Nanchang University, Nanchang, China
| | - Zhi-Kai Wan
- 1Department of Physiology, College of Medicine, Nanchang University, Nanchang, China
| | - Mei-Wen Yang
- 2Department of Nurse, Nanchang University Hospital, Nanchang 330006, Jiangxi, China
| | - Fen-Fang Hong
- 3Department of Experimental Teaching Center, Nanchang University, Nanchang, China
| | - Shu-Long Yang
- 1Department of Physiology, College of Medicine, Nanchang University, Nanchang, China.,3Department of Experimental Teaching Center, Nanchang University, Nanchang, China
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9
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Koulousakis P, Andrade P, Visser-Vandewalle V, Sesia T. The Nucleus Basalis of Meynert and Its Role in Deep Brain Stimulation for Cognitive Disorders: A Historical Perspective. J Alzheimers Dis 2020; 69:905-919. [PMID: 31104014 DOI: 10.3233/jad-180133] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The nucleus basalis of Meynert (nbM) was first described at the end of the 19th century and named after its discoverer, Theodor Meynert. The nbM contains a large population of cholinergic neurons that project their axons to the entire cortical mantle, the olfactory tubercle, and the amygdala. It has been functionally associated with the control of attention and maintenance of arousal, both key functions for appropriate learning and memory formation. This structure is well-conserved across vertebrates, although its degree of organization varies between species. Since early in the investigation of its functional and pathological significance, its degeneration has been linked to various major neuropsychiatric disorders. For instance, Lewy bodies, a hallmark in the diagnosis of Parkinson's disease, were originally described in the nbM. Since then, its involvement in other Lewy body and dementia-related disorders has been recognized. In the context of recent positive outcomes following nbM deep brain stimulation in subjects with dementia-associated disorders, we review the literature from an historical perspective focusing on how the nbM came into focus as a promising therapeutic option for patients with Alzheimer's disease. Moreover, we will discuss what is needed to further develop and widely implement this approach as well as examine novel medical indications for which nbM deep brain stimulation may prove beneficial.
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Affiliation(s)
- Philippos Koulousakis
- Department of Stereotactic and Functional Neurosurgery, University Hospital of Cologne, Germany.,European Graduate School of Neuroscience, Maastricht, The Netherlands
| | - Pablo Andrade
- Department of Neurosurgery, University Hospital of Cologne, Germany.,European Graduate School of Neuroscience, Maastricht, The Netherlands
| | - Veerle Visser-Vandewalle
- Department of Stereotactic and Functional Neurosurgery, University Hospital of Cologne, Germany.,European Graduate School of Neuroscience, Maastricht, The Netherlands
| | - Thibaut Sesia
- Department of Stereotactic and Functional Neurosurgery, University Hospital of Cologne, Germany.,European Graduate School of Neuroscience, Maastricht, The Netherlands
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10
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Linna M, Vuoti S, Silander K, Hörhammer I, Halminen O, Mikkola T, Koivuranta-Vaara P, Virta LJ, Koivusalo M, Ylisaukko-oja T. Impact of Anti-Dementia Medication on the Risk of Death and Causes of Death in Alzheimer’s Disease. J Alzheimers Dis 2019; 71:1297-1308. [DOI: 10.3233/jad-190288] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Miika Linna
- Aalto University/Health Care, Engineering, Management and Architecture (HEMA), Aalto, Finland
| | | | - Katariina Silander
- Aalto University/Health Care, Engineering, Management and Architecture (HEMA), Aalto, Finland
| | - Iiris Hörhammer
- Aalto University/Health Care, Engineering, Management and Architecture (HEMA), Aalto, Finland
| | - Olli Halminen
- Aalto University/Health Care, Engineering, Management and Architecture (HEMA), Aalto, Finland
| | - Teija Mikkola
- Finnish Local and Regional Authorities, Helsinki, Finland
| | | | - Lauri J. Virta
- Research Department, Social Insurance Institution of Finland, Turku, Finland
| | | | - Tero Ylisaukko-oja
- MedEngine, Helsinki, Finland
- University of Oulu, Center for Life Course Health Research, Oulu, Finland
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11
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Hampel H, Mesulam MM, Cuello AC, Farlow MR, Giacobini E, Grossberg GT, Khachaturian AS, Vergallo A, Cavedo E, Snyder PJ, Khachaturian ZS. The cholinergic system in the pathophysiology and treatment of Alzheimer's disease. Brain 2019; 141:1917-1933. [PMID: 29850777 DOI: 10.1093/brain/awy132] [Citation(s) in RCA: 886] [Impact Index Per Article: 177.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 03/29/2018] [Indexed: 12/19/2022] Open
Abstract
Cholinergic synapses are ubiquitous in the human central nervous system. Their high density in the thalamus, striatum, limbic system, and neocortex suggest that cholinergic transmission is likely to be critically important for memory, learning, attention and other higher brain functions. Several lines of research suggest additional roles for cholinergic systems in overall brain homeostasis and plasticity. As such, the brain's cholinergic system occupies a central role in ongoing research related to normal cognition and age-related cognitive decline, including dementias such as Alzheimer's disease. The cholinergic hypothesis of Alzheimer's disease centres on the progressive loss of limbic and neocortical cholinergic innervation. Neurofibrillary degeneration in the basal forebrain is believed to be the primary cause for the dysfunction and death of forebrain cholinergic neurons, giving rise to a widespread presynaptic cholinergic denervation. Cholinesterase inhibitors increase the availability of acetylcholine at synapses in the brain and are one of the few drug therapies that have been proven clinically useful in the treatment of Alzheimer's disease dementia, thus validating the cholinergic system as an important therapeutic target in the disease. This review includes an overview of the role of the cholinergic system in cognition and an updated understanding of how cholinergic deficits in Alzheimer's disease interact with other aspects of disease pathophysiology, including plaques composed of amyloid-β proteins. This review also documents the benefits of cholinergic therapies at various stages of Alzheimer's disease and during long-term follow-up as visualized in novel imaging studies. The weight of the evidence supports the continued value of cholinergic drugs as a standard, cornerstone pharmacological approach in Alzheimer's disease, particularly as we look ahead to future combination therapies that address symptoms as well as disease progression.
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Affiliation(s)
- Harald Hampel
- AXA Research Fund and Sorbonne University Chair, Paris, France.,Sorbonne University, GRC n° 21, Alzheimer Precision Medicine (APM), AP-HP, Pitié-Salpêtrière Hospital, Boulevard de l'hôpital, Paris, France.,Brain and Spine Institute (ICM), INSERM U 1127, CNRS UMR 7225, Boulevard de l'hôpital, Paris, France.,Institute of Memory and Alzheimer's Disease (IM2A), Department of Neurology, Pitié-Salpêtrière Hospital, AP-HP, Boulevard de l'hôpital, Paris, France
| | - M-Marsel Mesulam
- Cognitive Neurology and Alzheimer's Disease Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - A Claudio Cuello
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Canada.,Department of Neurology and Neurosurgery, McGill University, Montreal, Canada.,Department of Anatomy and Cell Biology, McGill University, Montreal, Canada
| | - Martin R Farlow
- Department of Neurology, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Ezio Giacobini
- Department of Internal Medicine, Rehabilitation and Geriatrics, University of Geneva Hospitals, Geneva, Switzerland
| | - George T Grossberg
- Department of Psychiatry and Behavioral Neuroscience, Saint Louis University School of Medicine, St Louis, MO, USA
| | - Ara S Khachaturian
- The Campaign to Prevent Alzheimer's Disease by 2020 (PAD2020), Potomac, MD, USA
| | - Andrea Vergallo
- AXA Research Fund and Sorbonne University Chair, Paris, France.,Sorbonne University, GRC n° 21, Alzheimer Precision Medicine (APM), AP-HP, Pitié-Salpêtrière Hospital, Boulevard de l'hôpital, Paris, France.,Brain and Spine Institute (ICM), INSERM U 1127, CNRS UMR 7225, Boulevard de l'hôpital, Paris, France.,Institute of Memory and Alzheimer's Disease (IM2A), Department of Neurology, Pitié-Salpêtrière Hospital, AP-HP, Boulevard de l'hôpital, Paris, France
| | - Enrica Cavedo
- AXA Research Fund and Sorbonne University Chair, Paris, France.,Sorbonne University, GRC n° 21, Alzheimer Precision Medicine (APM), AP-HP, Pitié-Salpêtrière Hospital, Boulevard de l'hôpital, Paris, France.,Brain and Spine Institute (ICM), INSERM U 1127, CNRS UMR 7225, Boulevard de l'hôpital, Paris, France.,Institute of Memory and Alzheimer's Disease (IM2A), Department of Neurology, Pitié-Salpêtrière Hospital, AP-HP, Boulevard de l'hôpital, Paris, France
| | - Peter J Snyder
- Department of Neurology, Alpert Medical School of Brown University, Providence, RI USA.,Ryan Institute for Neuroscience, University of Rhode Island, Kingston, RI, USA
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12
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Govindpani K, McNamara LG, Smith NR, Vinnakota C, Waldvogel HJ, Faull RL, Kwakowsky A. Vascular Dysfunction in Alzheimer's Disease: A Prelude to the Pathological Process or a Consequence of It? J Clin Med 2019; 8:E651. [PMID: 31083442 PMCID: PMC6571853 DOI: 10.3390/jcm8050651] [Citation(s) in RCA: 111] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 04/29/2019] [Accepted: 05/06/2019] [Indexed: 12/19/2022] Open
Abstract
Alzheimer's disease (AD) is the most prevalent form of dementia. Despite decades of research following several theoretical and clinical lines, all existing treatments for the disorder are purely symptomatic. AD research has traditionally been focused on neuronal and glial dysfunction. Although there is a wealth of evidence pointing to a significant vascular component in the disease, this angle has been relatively poorly explored. In this review, we consider the various aspects of vascular dysfunction in AD, which has a significant impact on brain metabolism and homeostasis and the clearance of β-amyloid and other toxic metabolites. This may potentially precede the onset of the hallmark pathophysiological and cognitive symptoms of the disease. Pathological changes in vessel haemodynamics, angiogenesis, vascular cell function, vascular coverage, blood-brain barrier permeability and immune cell migration may be related to amyloid toxicity, oxidative stress and apolipoprotein E (APOE) genotype. These vascular deficits may in turn contribute to parenchymal amyloid deposition, neurotoxicity, glial activation and metabolic dysfunction in multiple cell types. A vicious feedback cycle ensues, with progressively worsening neuronal and vascular pathology through the course of the disease. Thus, a better appreciation for the importance of vascular dysfunction in AD may open new avenues for research and therapy.
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Affiliation(s)
- Karan Govindpani
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.
| | - Laura G McNamara
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.
| | - Nicholas R Smith
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.
| | - Chitra Vinnakota
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.
| | - Henry J Waldvogel
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.
| | - Richard Lm Faull
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.
| | - Andrea Kwakowsky
- Centre for Brain Research, Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.
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13
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Characterisation of a Platinum-based Electrochemical Biosensor for Real-time Neurochemical Analysis of Choline. ELECTROANAL 2018. [DOI: 10.1002/elan.201800642] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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14
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Liu R, Crawford J, Callahan PM, Terry AV, Constantinidis C, Blake DT. Intermittent Stimulation of the Nucleus Basalis of Meynert Improves Working Memory in Adult Monkeys. Curr Biol 2017; 27:2640-2646.e4. [PMID: 28823679 PMCID: PMC5759307 DOI: 10.1016/j.cub.2017.07.021] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 06/07/2017] [Accepted: 07/11/2017] [Indexed: 10/19/2022]
Abstract
Acetylcholine in the neocortex is critical for executive function [1-3]. Degeneration of cholinergic neurons in aging and Alzheimer's dementia is commonly treated with cholinesterase inhibitors [4-7]; however, these are modestly effective and are associated with side effects that preclude effective dosing in many patients [8]. Electrical activation of the nucleus basalis (NB) of Meynert, the source of neocortical acetylcholine [9, 10], provides a potential method of improving cholinergic activation [11, 12]. Here we tested whether NB stimulation would improve performance of a working memory task in a nonhuman primate model. Unexpectedly, intermittent stimulation proved to be most beneficial (60 pulses per second, for 20 s every minute), whereas continuous stimulation often impaired performance. Pharmacological experiments confirmed that the effects depended on cholinergic activation. Donepezil, a cholinesterase inhibitor, restored performance in animals impaired by continuous stimulation but did not improve performance further during intermittent stimulation. Intermittent stimulation was rendered ineffective by either nicotinic or muscarinic receptor antagonists. In the months after stimulation began, performance also improved in sessions without stimulation. Our results reveal that intermittent NB stimulation can improve working memory, a finding that has implications for restoring cognitive function in aging and Alzheimer's dementia.
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Affiliation(s)
- Ruifeng Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China; Brain and Behavior Discovery Institute, Department of Neurology, Medical College of Georgia, Augusta University, 1120 15th Street, Augusta, GA 30912, USA
| | - Jonathan Crawford
- Brain and Behavior Discovery Institute, Department of Neurology, Medical College of Georgia, Augusta University, 1120 15th Street, Augusta, GA 30912, USA
| | - Patrick M Callahan
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, 1120 15th Street, Augusta, GA 30912, USA
| | - Alvin V Terry
- Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta University, 1120 15th Street, Augusta, GA 30912, USA
| | - Christos Constantinidis
- Department of Neurobiology and Anatomy, Wake Forest School of Medicine, Winston-Salem, NC, USA
| | - David T Blake
- Brain and Behavior Discovery Institute, Department of Neurology, Medical College of Georgia, Augusta University, 1120 15th Street, Augusta, GA 30912, USA.
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15
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Park KW, Kim EJ, Han HJ, Shim YS, Kwon JC, Ku BD, Park KH, Yi HA, Kim KK, Yang DW, Lee HW, Kang H, Kwon OD, Kim S, Lee JH, Chung EJ, Park SW, Park MY, Yoon B, Kim BC, Seo SW, Choi SH. Efficacy and tolerability of rivastigmine patch therapy in patients with mild-to-moderate Alzheimer's dementia associated with minimal and moderate ischemic white matter hyperintensities: A multicenter prospective open-label clinical trial. PLoS One 2017; 12:e0182123. [PMID: 28786987 PMCID: PMC5546604 DOI: 10.1371/journal.pone.0182123] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 07/12/2017] [Indexed: 12/04/2022] Open
Abstract
Background and objective Studies investigating the impact of white matter hyperintensities (WMHs) on the response of acetylcholinesterase inhibitors in patients with Alzheimer’s disease (AD) have presented inconsistent results. We aimed to compare the effects of the rivastigmine patch between patients with AD with minimal WMHs and those with moderate WMHs. Methods Three hundred patients with mild to moderate AD were enrolled in this multicenter prospective open-label study and divided into two groups. Group 1 comprised patients with AD with minimal WMHs and group 2 comprised those with moderate WMHs. The patients were treated with a rivastigmine patch for 24 weeks. Efficacy measures were obtained at baseline and after 24 weeks. The primary endpoint was the change in the AD Assessment Scale-Cognitive subscale (ADAS-Cog) from the baseline to the end of the study. Results Of the 300 patients, there were 206 patients in group 1 and 94 patients in group 2. The intention-to-treat group comprised 198 patients (group 1, n = 136; group 2, n = 46) during the 24-week study period. Demographic factors did not differ between group 1 and group 2. There were no significant differences in change in ADAS-cog between group 1 (-0.62±5.70) and group 2 (-0.23±5.98) after the 24-week rivastigmine patch therapy (p = 0.378). The patients in group 1 had a 0.63-point improvement from baseline on the Frontal Assessment Battery, while group 2 had a 0.16-point decline compared to baseline at the end of the study (p = 0.037). The rates of adverse events (AEs) (42.6 vs. 40.3%) and discontinuation due to AEs (10.3% vs. 4.3%) did not differ between the groups. Conclusions Although the efficacy and tolerability of rivastigmine patch therapy were not associated with WMH severity in patients with AD, some improvement in frontal function was observed in those with minimal WMHs. Trial registration ClinicalTrials.gov NCT01380288
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Affiliation(s)
- Kyung Won Park
- Department of Neurology, Cognitive Disorders and Dementia Center, Dong-A University College of Medicine and Institute of Convergence Bio-Health, Busan, South Korea
| | - Eun-Joo Kim
- Department of Neurology, Pusan National University Hospital and Biomedical Research Institute, Pusan National University School of Medicine, Busan, South Korea
| | - Hyun Jeong Han
- Department of Neurology, Seonam University College of Medicine, Myongji Hospital, Goyang, South Korea
| | - Yong S. Shim
- Department of Neurology, Holy Family Hospital, The Catholic University of Korea, School of Medicine, Bucheon, South Korea
| | - Jae C. Kwon
- Department of Neurology, Changwon Fatima Hospital, Changwon, South Korea
| | - Bon D. Ku
- Department of Neurology, Catholic Kwandong University College of Medicine, Gangneung, South Korea
| | - Kee Hyung Park
- Department of Neurology, Gachon University Gil Hospital, Incheon, South Korea
| | - Hyon-Ah Yi
- Department of Neurology, Keimyung University College of Medicine, Daegu, South Korea
| | - Kwang K. Kim
- Department of Neurology, Dongguk University College of Medicine, Seoul, South Korea
| | - Dong Won Yang
- Department of Neurology, The Catholic University of Korea, School of Medicine, Seoul, South Korea
| | - Ho-Won Lee
- Department of Neurology, Kyungpook National University School of Medicine, Daegu, South Korea
| | - Heeyoung Kang
- Department of Neurology, Gyeongsang National University College of Medicine, Jinju, South Korea
| | - Oh Dae Kwon
- Department of Neurology, Catholic University of Daegu School of Medicine, Daegu, South Korea
| | - SangYun Kim
- Department of Neurology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Jae-Hyeok Lee
- Department of Neurology, Pusan National University Yangsan Hospital, Yangsan, South Korea
| | - Eun Joo Chung
- Department of Neurology, Busan Paik Hospital, Inje University College of Medicine, Busan, South Korea
| | - Sang-Won Park
- Department of Neurology, Daegu Fatima Hospital, Daegu, South Korea
| | - Mee Young Park
- Department of Neurology, Yeungnam University College of Medicine, Daegu, South Korea
| | - Bora Yoon
- Department of Neurology, Konyang University College of Medicine, Daejeon, South Korea
| | - Byeong C. Kim
- Department of Neurology, Chonnam National University School of Medicine, Gwangju, South Korea
| | - Sang Won Seo
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - Seong Hye Choi
- Department of Neurology, Inha University School of Medicine, Incheon, South Korea
- * E-mail:
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16
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Salminen A, Kauppinen A, Kaarniranta K. Hypoxia/ischemia activate processing of Amyloid Precursor Protein: impact of vascular dysfunction in the pathogenesis of Alzheimer's disease. J Neurochem 2017; 140:536-549. [DOI: 10.1111/jnc.13932] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 12/05/2016] [Accepted: 12/10/2016] [Indexed: 12/13/2022]
Affiliation(s)
- Antero Salminen
- Department of Neurology; Institute of Clinical Medicine; University of Eastern Finland; Kuopio Finland
| | - Anu Kauppinen
- School of Pharmacy; Faculty of Health Sciences; University of Eastern Finland; Kuopio Finland
| | - Kai Kaarniranta
- Department of Ophthalmology; Institute of Clinical Medicine; University of Eastern Finland; Kuopio Finland
- Department of Ophthalmology; Kuopio University Hospital; Kuopio Finland
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17
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Nagai M, Hoshide S, Dote K, Kario K. Visit-to-visit blood pressure variability and dementia. Geriatr Gerontol Int 2016; 15 Suppl 1:26-33. [PMID: 26671154 DOI: 10.1111/ggi.12660] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/17/2015] [Indexed: 11/28/2022]
Abstract
Visit-to-visit blood pressure variability has been shown to be an independent risk factor for stroke and cognitive impairment. However, the underlying mechanisms are not fully understood. Artery remodeling and silent cerebral injury are suggested to be involved in the relationship between visit-to-visit blood pressure variability and cognitive impairment. The present review article summarizes the recent literature on these topics. Here we review visit-to-visit blood pressure variability, artery remodeling, silent cerebral injury and an issue regarding the impact of these components on dementia including Alzheimer's disease.
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Affiliation(s)
- Michiaki Nagai
- Department of Cardiology, Hiroshima City Asa Hospital, Hiroshima, Japan
| | - Satoshi Hoshide
- Division of Cardiovascular Medicine, Department of Medicine, Jichi Medical University School of Medicine, Tochigi, Japan
| | - Keigo Dote
- Department of Cardiology, Hiroshima City Asa Hospital, Hiroshima, Japan
| | - Kazuomi Kario
- Division of Cardiovascular Medicine, Department of Medicine, Jichi Medical University School of Medicine, Tochigi, Japan
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18
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Janik R, Thomason LAM, Chaudhary S, Dorr A, Scouten A, Schwindt G, Masellis M, Stanisz GJ, Black SE, Stefanovic B. Attenuation of functional hyperemia to visual stimulation in mild Alzheimer's disease and its sensitivity to cholinesterase inhibition. Biochim Biophys Acta Mol Basis Dis 2015; 1862:957-65. [PMID: 26521151 DOI: 10.1016/j.bbadis.2015.10.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 10/21/2015] [Accepted: 10/25/2015] [Indexed: 01/09/2023]
Abstract
Despite the growing recognition of the significance of cerebrovascular impairment in the etiology and progression of Alzheimer's disease (AD), the early stage brain vascular dysfunction and its sensitivity to pharmacological interventions is still not fully characterized. Due to the early and aggressive treatment of probable AD with cholinesterase inhibitors (ChEI), which in and of themselves have direct effects on brain vasculature, the vast majority of hemodynamic measurements in early AD subjects reported hitherto have consequently been made only after the start of treatment, complicating the disentanglement of disease- vs. treatment-related effects on the cerebral vasculature. To address this gap, we used pseudo continuous arterial spin labeling MRI to measure resting perfusion and visual stimulation elicited changes in cerebral blood flow (CBF) and blood oxygenation dependent (BOLD) fMRI signal in a cohort of mild AD patients immediately prior to, 6months post, and 12months post commencement of open label cholinesterase inhibitor treatment. Although patients exhibited no gray matter atrophy prior to treatment and their resting perfusion was not distinguishable from that in age, education and gender-matched controls, the patients' visual stimulation-elicited changes in BOLD fMRI and blood flow were decreased by 10±4% (BOLD) and 23±2% (CBF), relative to those in controls. Induction of cholinesterase inhibition treatment was associated with a further, 7±2% reduction in patients' CBF response to visual stimulation, but it stabilized, at this new lower level, over the follow-up period. Likewise, MMSE scores remained stable during the treatment; furthermore, higher MMSE scores were associated with higher perfusion responses to visual stimulation. This study represents the initial step in disentangling the effects of AD pathology from those of the first line treatment with cholinesterase inhibitors on cerebral hemodynamics and supports the use of arterial spin labeling MRI for quantitative evaluation of the brain vascular function in mild Alzheimer's disease. The findings provide evidence of a pronounced deficit in the visual cortex hyperemia despite the relative sparing of visual function in early stage AD, its reduction with ChEI treatment induction, and its stabilization in the first year of cholinesterase inhibition treatment. This article is part of a Special Issue entitled: Vascular Contributions to Cognitive Impairment and Dementia edited by M. Paul Murphy, Roderick A. Corriveau and Donna M. Wilcock.
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Affiliation(s)
- Rafal Janik
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada; Department of Medical Biophysics, University of Toronto, 610 University Avenue, Toronto, ON M5G 2M9, Canada.
| | - Lynsie A M Thomason
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada
| | - Simone Chaudhary
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada; Department of Medical Biophysics, University of Toronto, 610 University Avenue, Toronto, ON M5G 2M9, Canada
| | - Adrienne Dorr
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada
| | - Amy Scouten
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada; Department of Medical Biophysics, University of Toronto, 610 University Avenue, Toronto, ON M5G 2M9, Canada
| | - Graeme Schwindt
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada
| | - Mario Masellis
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada; Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada
| | - Greg J Stanisz
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada; Department of Medical Biophysics, University of Toronto, 610 University Avenue, Toronto, ON M5G 2M9, Canada; Department of Nerurosurgery and Pediatrics Neurosurgery, Medical University of Lublin, Aleje Raclawickie 1, 20-059 Lublin, Poland
| | - Sandra E Black
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada; Institute of Medical Sciences, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada; Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada; Department of Medicine (Neurology), Sunnybrook Health Sciences Centre University of Toronto, Canada; Canadian Partnership for Stroke Recovery Sunnybrook Site, Canada
| | - Bojana Stefanovic
- Sunnybrook Research Institute, 2075 Bayview Avenue, Toronto, ON M4N 3M5, Canada; Department of Medical Biophysics, University of Toronto, 610 University Avenue, Toronto, ON M5G 2M9, Canada; Canadian Partnership for Stroke Recovery Sunnybrook Site, Canada
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19
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Wharton W, Gleason CE, Dowling NM, Carlsson CM, Brinton EA, Santoro MN, Neal-Perry G, Taylor H, Naftolin F, Lobo RA, Merriam G, Manson JE, Cedars MI, Miller VM, Black DM, Budoff M, Hodis HN, Harman SM, Asthana S. The KEEPS-Cognitive and Affective Study: baseline associations between vascular risk factors and cognition. J Alzheimers Dis 2015; 40:331-41. [PMID: 24430001 DOI: 10.3233/jad-130245] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Midlife vascular risk factors influence later cognitive decline and Alzheimer's disease (AD). The decrease in serum estradiol levels during menopause has been associated with cognitive impairment and increased vascular risk, such as high blood pressure (BP), which independently contributes to cognitive dysfunction and AD. We describe the extent to which vascular risk factors relate to cognition in healthy, middle-aged, recently postmenopausal women enrolled in the Kronos Early Estrogen Prevention Cognitive and Affective Study (KEEPS-Cog) at baseline. KEEPS-Cog is a double-blind, randomized, placebo-controlled, parallel group, clinical trial, investigating the efficacy of low-dose, transdermal 17β-estradiol and oral conjugated equine estrogen on cognition. All results are cross-sectional and represent baseline data only. Analyses confirm that the KEEPS-Cog cohort (n = 571) was middle aged (mean 52.7 years, range 42-59 years), healthy, and free of cognitive dysfunction. Higher systolic BP was weakly related to poorer performance in auditory working memory and attention (p = 0.004; adjusted for multiple comparisons p = 0.10). This relationship was not associated with endogenous hormone levels, and systolic BP was not related to any other cognitive domain. BP levels may be more sensitive than other vascular risk factors in detecting subtle differences in cognitive task performance in healthy, recently menopausal women. Lower BP early in menopause may affect cognitive domains known to be associated with AD.
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Affiliation(s)
- Whitney Wharton
- Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA Emory Alzheimer's Disease Research Center, (ADRC) Atlanta, GA, USA
| | - Carey E Gleason
- Department of Medicine, University of Wisconsin, School of Medicine and Public Health, Madison, WI, USA Geriatric Research, Education and Clinical Center (GRECC), William S. Middleton Memorial Veterans Hospital, Madison, WI, USA Wisconsin Alzheimer's Disease Research Center, (ADRC) Madison, WI, USA
| | - N Maritza Dowling
- Department of Medicine, University of Wisconsin, School of Medicine and Public Health, Madison, WI, USA Wisconsin Alzheimer's Disease Research Center, (ADRC) Madison, WI, USA University of Wisconsin, Department of Biostatistics and Medical Informatics, Madison, WI, USA
| | - Cynthia M Carlsson
- Department of Medicine, University of Wisconsin, School of Medicine and Public Health, Madison, WI, USA Geriatric Research, Education and Clinical Center (GRECC), William S. Middleton Memorial Veterans Hospital, Madison, WI, USA Wisconsin Alzheimer's Disease Research Center, (ADRC) Madison, WI, USA
| | - Eliot A Brinton
- Cardiovascular Genetics, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - M Nanette Santoro
- Obstetrics & Gynecology, University of Colorado School of Medicine, Aurora, CO, USA
| | | | - Hugh Taylor
- Obstetrics & Gynecology, Yale University School of Medicine, New Haven, CT, USA
| | | | - Rogerio A Lobo
- Obstetrics & Gynecology, Columbia University School of Medicine, New York, NY, USA
| | - George Merriam
- VA Puget Sound Health Care System and Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, WA, USA
| | - Joann E Manson
- Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Marcelle I Cedars
- Obstetrics & Gynecology, University of California at San Francisco, San Francisco, CA, USA
| | - Virginia M Miller
- Surgery & Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN, USA
| | - Dennis M Black
- Epidemiology & Biostatistics, University of California at San Francisco, San Francisco, CA, USA
| | - Matthew Budoff
- Medicine, Los Angeles Biomedical Research Institute, Torrance, CA, USA
| | - Howard N Hodis
- Atherosclerosis Research Unit, University of Southern California, Los Angeles, CA, USA
| | - S Mitchell Harman
- Kronos Longevity Research Institute and Phoenix VA Medical Center, Phoenix, AZ, USA
| | - Sanjay Asthana
- Department of Medicine, University of Wisconsin, School of Medicine and Public Health, Madison, WI, USA Geriatric Research, Education and Clinical Center (GRECC), William S. Middleton Memorial Veterans Hospital, Madison, WI, USA Wisconsin Alzheimer's Disease Research Center, (ADRC) Madison, WI, USA
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20
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Gąsecki D, Kwarciany M, Nyka W, Narkiewicz K. Hypertension, brain damage and cognitive decline. Curr Hypertens Rep 2014; 15:547-58. [PMID: 24146223 PMCID: PMC3838597 DOI: 10.1007/s11906-013-0398-4] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Loss of cognitive function is one the most devastating manifestations of ageing and vascular disease. Cognitive decline is rapidly becoming an important cause of disability worldwide and contributes significantly to increased mortality. There is growing evidence that hypertension is the most important modifiable vascular risk factor for development and progression of both cognitive decline and dementia. High blood pressure contributes to cerebral small and large vessel disease resulting in brain damage and dementia. A decline in cerebrovascular reserve capacity and emerging degenerative vascular wall changes underlie complete and incomplete brain infarcts, haemorrhages and white matter hyperintensities. This review discusses the complexity of factors linking hypertension to brain functional and structural changes, and to cognitive decline and dementia. The evidence for possible clinical markers useful for prevention of decreased cognitive ability, as well as recent data on vascular mechanism in the pathogenesis of cognitive decline, and the role of antihypertensive therapies in long-term prevention of late-life cognitive decline will be reviewed.
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Affiliation(s)
- Dariusz Gąsecki
- Department of Neurology of Adults, Medical University of Gdańsk, Gdańsk, Poland
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Woo DC, Lenkinski RE. Neurochemical changes observed by in vivo proton magnetic resonance spectroscopy in the mouse brain postadministration of scopolamine. Acad Radiol 2014; 21:1072-7. [PMID: 25018079 DOI: 10.1016/j.acra.2014.04.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 04/12/2014] [Accepted: 04/14/2014] [Indexed: 11/26/2022]
Abstract
RATIONALE AND OBJECTIVES This study is aimed at investigating neurochemical changes in scopolamine (SCP)-induced memory impairment using spatially localized in vivo magnetic resonance spectroscopy (MRS) of the hippocampus. MATERIALS AND METHODS Four groups of mice (eight mice per group) were scanned after the injection of different SCP doses: 0, 1, 3, and 5 mg/kg (intraperitoneally). All the animals received (1)H MRS of their hippocampus at two time intervals: 30 minutes and 72 hours after SCP injection. RESULTS This work demonstrated that the doses of 3 mg/kg SCP or higher reduce the concentration of total choline-containing compounds, and these levels returned to baseline after 72 hours. These results are consistent with observations made by others using more invasive brain dialysis approaches. The levels of glutamate and glutamic compounds (glutamate + glutamine) were slightly changed at 3 and 5 mg/kg SCP dose, but the differences were not statistically significant (P > .05). These findings suggest that SCP produces transient, in vivo measurable alterations in the cholinergic system in the hippocampus. CONCLUSIONS On this basis, we conclude that in vivo MRS is a feasible noninvasive method to probe aspects of the alterations induced by SCP in the cholinergic neurotransmission pathways in both animal models and human studies of memory impairment.
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Ahmad MA, Najmi AK, Mujeeb M, Akhtar M. Neuroprotective effect of guggulipid alone and in combination with aspirin on middle cerebral artery occlusion (MCAO) model of focal cerebral ischemia in rats. Toxicol Mech Methods 2014; 24:438-47. [DOI: 10.3109/15376516.2014.939320] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Abstract
Rivastigmine is a second-generation cholinesterase inhibitor with selectivity for the CNS, with capacity to inhibit both acetylcholinesterase and butyrylcholinesterase. Rivastigmine is currently approved for the treatment of mild-to-moderate Alzheimer's disease. In addition to its effects on cognition and activities of daily living, rivastigmine appears to be useful in preventing and controlling behavioral and neuropsychiatric manifestations in Alzheimer's disease and dementia with Lewy bodies. This drug profile could be potentially useful in patients with subcortical vascular dementia who often present these symptoms. Small open-label studies of patients with subcortical vascular dementia showed that rivastigmine improved attention, executive function, apathy and other behavioral deficits. Rivastigmine appears to be a promising agent in vascular dementia but its effects remain to be established in double-blind, placebo-controlled clinical trials.
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Affiliation(s)
- Gustavo C Román
- University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, Mail Code 7883, San Antonio, TX 78229 3900, USA.
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Glodzik L, Randall C, Rusinek H, de Leon MJ. Cerebrovascular reactivity to carbon dioxide in Alzheimer's disease. J Alzheimers Dis 2013; 35:427-40. [PMID: 23478306 DOI: 10.3233/jad-122011] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
There is growing evidence that cerebrovascular reactivity to carbon dioxide (CVRCO2) is impaired in Alzheimer's disease (AD). Preclinical and animal studies suggest chronic hypercontractility in brain vessels in AD. We review (a) preclinical studies of mechanisms for impaired CVRCO2 in AD; (b) clinical studies of cerebrovascular function in subjects with AD dementia, mild cognitive impairment (MCI), and normal cognition. Although results of clinical studies are inconclusive, an increasing number of reports reveal an impairment of vascular reactivity to carbon dioxide in subjects with AD, and possibly also in MCI. Thus, CVRCO2 may be an attractive means to detect an early vascular dysfunction in subjects at risk.
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Affiliation(s)
- Lidia Glodzik
- Center for Brain Health, Department of Psychiatry, New York University School of Medicine, New York, NY 10016, USA.
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Reig-Puig L, Antón-Rodrigo I, Sánchez-Ferrín P. Relación entre hipertensión arterial y la demencia. HIPERTENSION Y RIESGO VASCULAR 2011. [DOI: 10.1016/j.hipert.2011.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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Tarawneh R, Holtzman DM. Biomarkers in translational research of Alzheimer's disease. Neuropharmacology 2010; 59:310-22. [PMID: 20394760 DOI: 10.1016/j.neuropharm.2010.04.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2009] [Revised: 03/14/2010] [Accepted: 04/07/2010] [Indexed: 10/19/2022]
Abstract
The identification and characterization of amyloid-beta (Abeta) and tau as the main pathological substrates of Alzheimer's disease (AD) have driven many efforts in search for suitable biomarkers for AD. In the last decade, research in this area has focused on developing a better understanding of the principles that govern protein deposition, mechanisms that link aggregation to toxicity and neuronal death, and a better understanding of protein dynamics in brain tissue, interstitial fluid and CSF. While Abeta and tau represent the two key pathological mediators of disease, other aspects of this multifaceted disease (e.g. oxidative stress, calcium-mediated toxicity, and neuroinflammation) are being unraveled, with the hope to develop a more comprehensive approach in exploring disease mechanisms. This has not only expanded possible areas for disease-modifying therapies, but has also allowed the introduction of novel, and potentially useful, fluid and radiological markers for the presence and progression of AD pathology. There is no doubt that the identification of several fluid and imaging biomarkers that can reliably detect the early stages of AD will have great implications in the design of clinical trials, in the selection of homogenous research populations, and in the assessment of disease outcomes. Markers with good diagnostic specificity will aid researchers in differentiating individuals with preclinical and probable AD from individuals who do not have AD pathology or have other dementing disorders. Markers that change with disease progression may offer utility in assessing the rates of disease progression and the efficacy of potential therapeutic agents on AD pathology. For both of these purposes, CSF Abeta42, amyloid imaging, and CSF tau appear to be very good markers of the presence of AD pathology as well as predictive of who will progress from MCI to AD. Volumetric MRI is also good at separating individuals with MCI and AD from controls and is predictive of who will progress from MCI to AD. Perhaps the most important role biomarkers will have, and the most needed at this time, lies in the identification of individuals who are cognitively normal, and yet have evidence of AD pathology (i.e. preclinical AD). Such individuals, it appears, can be identified with CSF Abeta42, amyloid imaging, and CSF tau. Such individuals are the most likely to benefit from future disease modifying/prevention therapies as they become available, and therefore represent the population in which the field can make the biggest therapeutic impact.
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Affiliation(s)
- Rawan Tarawneh
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA.
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Lam B, Hollingdrake E, Kennedy JL, Black SE, Masellis M. Cholinesterase inhibitors in Alzheimer's disease and Lewy body spectrum disorders: the emerging pharmacogenetic story. Hum Genomics 2010; 4:91-106. [PMID: 20038497 PMCID: PMC3525201 DOI: 10.1186/1479-7364-4-2-91] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
This review provides an update on the current state of pharmacogenetic research in the treatment of Alzheimer's disease (AD) and Lewy body disease (LBD) as it pertains to the use of cholinesterase inhibitors (ChEI). AD and LBD are first reviewed from clinical and pathophysiological perspectives. This is followed by a discussion of ChEIs used in the symptomatic treatment of these conditions, focusing on their unique and overlapping pharmacokinetic and pharmacodynamic profiles, which can be used to identify candidate genes for pharmacogenetics studies. The literature published to date is then reviewed and limitations are discussed. This is followed by a discussion of potential endophenotypes which may help to refine future pharmacogenetic studies of response and adverse effects to ChEIs.
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Affiliation(s)
- Benjamin Lam
- L.C. Campbell Cognitive Neurology Research Unit, Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Canada
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Abstract
Although hypertension is well known as a cause of vascular dementia (VaD), recent findings highlight the role of hypertension in the pathogenesis of Alzheimer's disease (AD) as well as mild cognitive impairment (MCI). Recent studies have shown that disruption of diurnal blood pressure (BP) variation is closely associated with cognitive impairment via injury of the small cerebral arteries indicating that long-standing hypertension constitutes a risk of brain matter atrophy or white matter lesions (WMLs). In several clinical trials, BP-lowering with antihypertensive agents was suggested to reduce the risk of dementia or cognitive decline. This review paper focuses on the role of hypertension as a risk factor for cognitive impairment, and summarizes current knowledge on the relationships between ambulatory BP monitoring (ABPM) and cognitive impairment. Finally, an overview of the impact of antihypertensive therapy on dementia prevention is provided.
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Van Beek AHEA, Claassen JAHR. The cerebrovascular role of the cholinergic neural system in Alzheimer's disease. Behav Brain Res 2010; 221:537-42. [PMID: 20060023 DOI: 10.1016/j.bbr.2009.12.047] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Accepted: 12/26/2009] [Indexed: 10/20/2022]
Abstract
The intrinsic cholinergic innervation of the cortical microvessels contains both subcortical pathways and local cortical interneurons mediated by muscarinic and nicotinic acetylcholine receptors. Stimulation of this system leads to vasodilatation. In the extrinsic innervation, choline acts as a selective agonist for the α7-nicoticinic acetylcholine receptor on the sympathetic nerves to cause vasodilatation, and through this mechanism, cholinergic modulation may affect this sympathetic vasodilatation. Alzheimer's disease is characterized by a cerebral cholinergic deficit and cerebral blood flow is diminished. Cholinesterase inhibitors, important drugs in the treatment of Alzheimer's disease, could influence the cerebral blood flow through stimulation of the intrinsic cholinergic cerebrovascular innervation. Indeed, cholinesterase inhibitors improve cerebral blood flow in Alzheimer patients who respond to treatment. Further, cerebrovascular reactivity and neurovascular coupling are impaired in Alzheimer's disease and both can be improved by cholinesterase inhibitors. Conversely, cholinesterase inhibitors inhibit the α7-nicoticinic acetylcholine receptor on extrinsic sympathetic nerves and thus may impair vasodilatation. The net outcome of these opposing effects in clinical practice remains unknown. Moreover, it is uncertain whether the regulation of cerebral blood flow during blood pressure changes (cerebral autoregulation) is impaired in patients with Alzheimer's disease. Technological developments now allow us to dynamically measure blood pressure, cerebral blood flow, and cerebral cortical oxygenation. Using simple maneuvers like single sit-stand and repeated sit-stand maneuvers, the regulation of cerebral perfusion in patients with Alzheimer's disease can easily be measured. Sit-stand maneuvers can be considered as a provocation test for cerebral autoregulation, and provide excellent opportunities to study the cerebrovascular effects of cholinesterase inhibitors.
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Affiliation(s)
- Arenda H E A Van Beek
- Radboud University Nijmegen Medical Centre, Department of Geriatric Medicine and Alzheimer Centre Nijmegen, The Netherlands
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Wang J, Zhang HY, Tang XC. Cholinergic deficiency involved in vascular dementia: possible mechanism and strategy of treatment. Acta Pharmacol Sin 2009; 30:879-88. [PMID: 19574993 PMCID: PMC4006646 DOI: 10.1038/aps.2009.82] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2009] [Accepted: 04/29/2009] [Indexed: 01/08/2023] Open
Abstract
Vascular dementia (VaD) is a progressive neurodegenerative disease with a high prevalence. Several studies have recently reported that VaD patients present cholinergic deficits in the brain and cerebrospinal fluid (CSF) that may be closely related to the pathophysiology of cognitive impairment. Moreover, cholinergic therapies have shown promising effects on cognitive improvement in VaD patients. The precise mechanisms of these cholinergic agents are currently not fully understood; however, accumulating evidence indicates that these drugs may act through the cholinergic anti-inflammatory pathway, in which the efferent vagus nerve signals suppress pro-inflammatory cytokine release and inhibit inflammation, although regulation of oxidative stress and energy metabolism, alleviation of apoptosis may also be involved. In this paper, we provide a brief overview of the cholinergic treatment strategy for VaD and its relevant mechanisms of anti-inflammation.Acta Pharmacologica Sinica (2009) 30: 879-888; doi: 10.1038/aps.2009.82.
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Affiliation(s)
- Juan Wang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Hai-yan Zhang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
| | - Xi-can Tang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 201203, China
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Emerging hypotheses regarding the influences of butyrylcholinesterase-K variant, APOE epsilon 4, and hyperhomocysteinemia in neurodegenerative dementias. Med Hypotheses 2009; 73:230-50. [PMID: 19359103 DOI: 10.1016/j.mehy.2009.01.050] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2008] [Revised: 12/04/2008] [Accepted: 01/24/2009] [Indexed: 01/20/2023]
Abstract
Non-enzymatic functions of butyrylcholinesterase (BuChE) include prevention of the aggregation of amyloid-beta peptide (A beta) in a concentration-dependent manner. This is mediated by the C-terminus of the protein, distal from the enzymatic site. The BuChE-K variant polymorphism lowers expression of BuChE protein and/or alters C-terminal activity. In combination with factors that increase production or reduce elimination of A beta, and/or increase susceptibility to A beta toxicity - such as the apolipoprotein E (APOE) epsilon 4 allele and/or hyperhomocysteinemia - BuChE-K may accelerate cholinergic synaptic and neuronal damage and cognitive decline. A beta-mediated damage to ascending cholinergic pathways may be further accentuated by Lewy body and/or cerebrovascular disease. As the disease advances and functioning cholinergic synapses disappear, both the rapid cognitive decline and response to cholinesterase inhibitor therapy in individuals with these factors may diminish. Non-enzymatic functions of the BuChE protein, APOE epsilon 4 status and hyperhomocysteinemia influence the progression of pathology, symptom expression, and response to cholinesterase inhibition in a stage-specific manner in neurodegenerative disorders associated with Alzheimer, Lewy body and vascular pathology.
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Decreased activation along the dorsal visual pathway after a 3-month treatment with galantamine in mild Alzheimer disease: a functional magnetic resonance imaging study. J Clin Psychopharmacol 2009; 29:147-56. [PMID: 19512976 DOI: 10.1097/jcp.0b013e31819a8f2e] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Visual perception has been shown to be altered in Alzheimer disease (AD) patients, and it is associated with decreased cognitive function. Galantamine is an active cholinergic agent, which has been shown to lead to improved cognition in mild to moderate AD patients. This study examined brain activation in a group of mild AD patients after a 3-month open-label treatment with galantamine. The objective was to examine the changes in brain activation due to treatment. There were 2 tasks to visual perception. The first task was a face-matching task to test the activation along the ventral visual pathway, and the second task was a location-matching task to test neuronal function along the dorsal pathway. Brain activation was measured using functional magnetic resonance imaging. There were 5 mild AD patients in the study. There were no differences in the task performance and in the cognitive scores of the Consortium to Establish a Registry for Alzheimer's Disease battery before and after treatment. In the location-matching task, we found a statistically significant decrease in activation along the dorsal visual pathway after galantamine treatment. A previous study found that AD patients had higher activation in the location-matching task compared with healthy controls. There were no differences in activation for the face-matching task after treatment. Our data indicate that treatment with galantamine leads to more efficient visual processing of stimuli or changes the compensatory mechanism in the AD patients. A visual perception task recruiting the dorsal visual system may be useful as a biomarker of treatment effects.
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Gispen-de Wied CC, Kritsidima M, Elferink AJA. The validity of biomarkers as surrogate endpoints in Alzheimer's disease by means of the Quantitative Surrogate Validation Level of Evidence Scheme (QSVLES). J Nutr Health Aging 2009; 13:376-87. [PMID: 19300886 DOI: 10.1007/s12603-009-0049-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
OBJECTIVE To evaluate the validity of biomarkers that are currently being proposed as potential surrogate endpoints in AD clinical trials with the aid of the "Quantitative Surrogate Validation Level of Evidence Schema" (QSVLES) proposed by Lassere et.al. (1). PROCEDURE A Pubmed literature search was conducted to identify AD biomarkers with SEP potential, and the QSVLES was applied to determine the extent of the SEP validity. RESULTS MRI, PET and MRS measures attained a total validity score of 4, NAA/Cre a total score of 5, and cerebral blood flow (SPECT), Abeta , Tau and APP a total score of 2. None of these biomarkers could fall into the rank of Levels 1 or 2, reserved for SEPs, according to the QSVLES criteria. This was mainly attributed to the lack of sufficient evidence that was derived from high ranking studies (RCT, prospective observational studies). CONCLUSION Though residing on SEPs as sole determinants of the benefit/risk ratio of AD medications seems to be pretty far, there could be certain cases where the use of SEPs may be beneficial, making efficient therapies available faster when there is a major public health interest involved. However, the potential risks of relying on invalid SEPs should not be underestimated and therefore the research on SEP validation and the development of specific validation guidance should be encouraged. The QSVLES, though not devoid of criticism, may be proposed as a starting point.
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Ellis JR, Nathan PJ, Villemagne VL, Mulligan RS, Saunder T, Young K, Smith CL, Welch J, Woodward M, Wesnes KA, Savage G, Rowe CC. Galantamine-induced improvements in cognitive function are not related to alterations in alpha(4)beta (2) nicotinic receptors in early Alzheimer's disease as measured in vivo by 2-[18F]fluoro-A-85380 PET. Psychopharmacology (Berl) 2009; 202:79-91. [PMID: 18949462 DOI: 10.1007/s00213-008-1347-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2008] [Accepted: 09/19/2008] [Indexed: 01/25/2023]
Abstract
INTRODUCTION The nicotinic acetylcholine receptor (nAChR) system plays a regulatory role in a number of cognitive processes. Cholinesterase inhibitors (i.e., galantamine) that potentiate cholinergic neurotransmission improve cognitive function in Alzheimer's disease (AD); however, the relationship between these effects and associated changes in nAChRs are yet to be established in vivo. MATERIALS AND METHODS 2-[18F]Fluoro-A-85380 (2-FA) binds to nAChRs and with positron emission tomography (PET) imaging provides a composite measure of receptor density and ligand affinity. This study aimed to: (1) quantify nAChRs in vivo in 15 drug-naïve patients with mild AD before and after chronic treatment with galantamine, using 2-FA and PET, and (2) examine the relationship between treatment-induced changes in nAChRs and improvements in cognitive function. Participants were nonsmokers and underwent extensive cognitive testing and a PET scan after injection of approximately 200 MBq of 2-FA on two occasions (before and after 12 weeks, galantamine treatment). A 3-day washout period preceded the second scan. Brain regional 2-FA binding was assessed through a simplified estimation of distribution volume (DV(S)). RESULTS Performance on global measures of cognition significantly improved following galantamine treatment (p < 0.05). This improvement extended to specific cognitive measures of language and verbal learning. No significant differences in nAChR DV(S) before and after galantamine treatment were found. The treatment-induced improvement in cognition was not correlated with regional or global nAChR DV(S), suggesting that changes in nAChRs may not be responsible for the improvements in cognition following galantamine in patients with mild AD.
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Affiliation(s)
- J R Ellis
- School of Psychology, Psychiatry, and Psychological Medicine, Monash University, Melbourne, Victoria, Australia.
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Tangwongchai S, Thavichachart N, Senanarong V, Poungvarin N, Phanthumchinda K, Praditsuwan R, Nidhinandana S, Chankrachang S. Galantamine for the treatment of BPSD in Thai patients with possible Alzheimer's disease with or without cerebrovascular disease. Am J Alzheimers Dis Other Demen 2008; 23:593-601. [PMID: 18845693 PMCID: PMC10846018 DOI: 10.1177/1533317508320603] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2024]
Abstract
OBJECTIVES This study was to investigate an efficacy of galantamine in treatment of behavioral and psychological symptoms of dementia in Thai elderly who suffered from possible Alzheimer's disease (AD) with or without cerebrovascular disease and vascular dementia. METHODS A 6-month, multicenter, open-label, uncontrolled trial was undertaken in 75 patients. Eligible patients received an initial galantamine dose of 8 mg/dayand escalated over 5 to 8 weeks to maintenance doses of 16 or 24 mg/day. The behavioral response was assessed as an intention-to-treat analysis using the Behavioral Pathology in Alzheimer's Disease Rating Scale (BEHAVE-AD). RESULTS Galantamine improved behavioral and psychological symptoms of dementia (P < .05 vs baseline) over the 24 weeks of treatment. BEHAVE-AD score was significantly improved from baseline in paranoid and delusion ideation, diurnal rhythm disturbances, anxieties, and phobias. CONCLUSIONS Galantamine may be a well-tolerated and effective treatment option for improving psychotic, behavioral, and psychological symptoms in Thai elderly with possible AD with or without cerebrovascular disease and vascular dementia.
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Affiliation(s)
- S Tangwongchai
- Department of Psychiatry, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand.
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Charbonneau C, Massoud F, Dorais M, LeLorier J. A retrospective study of cholinesterase inhibitors for Alzheimer's disease: cerebrovascular disease as a predictor of patient outcomes. Curr Med Res Opin 2008; 24:3287-94. [PMID: 19032117 DOI: 10.1185/03007990802417713] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND Dementia may be caused by Alzheimer's disease (AD), cerebrovascular disease (CVD), or a combination of both. When CVD is associated with dementia, survival is thought to be reduced. It is unclear whether treatment with cholinesterase inhibitors (ChEIs), which has been found to slow disease progression in AD patients, has similar benefits in vascular forms of dementia. OBJECTIVES The present study was designed to determine whether co-existing CVD is associated with survival or time to nursing home placement (NHP) among AD patients treated with ChEIs. Findings of poorer outcomes in patients with versus without CVD might argue against the use of ChEIs for AD patients in whom CVD co-exists. METHODS A retrospective cohort study was undertaken using the Régie de l'Assurance Maladie du Québec (RAMQ) databases to examine the time to NHP or death for AD patients aged 66+, with or without CVD, treated with ChEIs between July 1, 2000, and June 30, 2003. Because ChEIs are approved only for AD in Canada, a ChEI prescription was used as a surrogate for an AD diagnosis. Separate analyses were performed for patients with persistent ChEI use and those who discontinued ChEI therapy. RESULTS A total of 4428 patients met inclusion criteria for AD with CVD; 13 512 were classified as having AD alone. For the composite endpoint of NHP or death, 1000-day survival rates were lower among AD patients with versus without CVD (p < 0.01), but absolute differences were very small (84 vs. 86% with continuous ChEI use; 77 vs. 78% with discontinuous ChEI therapy). Of the secondary endpoints, time to death was shorter for patients with versus without CVD, but time to NHP did not differ between groups. LIMITATIONS Results may have been affected by selection (misclassification) bias and between-group differences in smoking, body mass index, and duration of ChEI therapy. CONCLUSIONS Associations between co-existing CVD and time to NHP or death appeared to be of little clinical relevance among AD patients treated with ChEIs. The lack of difference between AD patients with and without CVD suggests that CVD should not be used as a reason to deny AD patients access to ChEI treatment.
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Affiliation(s)
- Claudie Charbonneau
- Centre hospitalier de l'Université de Montréal Research Center - Hôtel-Dieu, Montréal, Québec, Canada
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McGeown WJ, Shanks MF, Venneri A. Prolonged cholinergic enrichment influences regional cortical activation in early Alzheimer's disease. Neuropsychiatr Dis Treat 2008; 4:465-76. [PMID: 18728791 PMCID: PMC2518373 DOI: 10.2147/ndt.s2461] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Neuroimaging studies of cholinesterase inhibitor (ChEI) treatment in Alzheimer's disease (AD) indicate that the short and long term actions of ChEIs are dissimilar. fMRI studies of the ChEI rivastigmine have focused on its short term action. In this exploratory study the effect of prolonged (20 weeks) rivastigmine treatment on regional brain activity was measured with fMRI in patients with mild AD. Eleven patients with probable AD and nine age-matched controls were assessed with a Pyramids and Palm Trees semantic association and an n-back working memory fMRI paradigm. In the patient group only, the assessment was repeated after 20 weeks of treatment. There was an increase in task-related brain activity after treatment with activations more like those of normal healthy elderly. Behaviorally, however, there were no significant differences between baseline and retest scores, with a range of performance probably reflecting variation in drug efficacy across patients. Variable patient response and drug dynamic/kinetic factors in small patient groups will inevitably bias (either way) the effect size of any relevant drug related changes in activation. Future studies should take drug response into account to provide more insight into the benefits of ChEI drugs at the individual level.
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Kobayashi S, Tateno M, Utsumi K, Takahashi A, Saitoh M, Morii H, Fujii K, Teraoka M. Quantitative analysis of brain perfusion SPECT in Alzheimer's disease using a fully automated regional cerebral blood flow quantification software, 3DSRT. J Neurol Sci 2007; 264:27-33. [PMID: 17764699 DOI: 10.1016/j.jns.2007.07.015] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2006] [Revised: 03/09/2007] [Accepted: 07/11/2007] [Indexed: 12/01/2022]
Abstract
PURPOSE The clinical symptoms of Alzheimer's disease (AD) show great diversity depending on the clinical stage. We investigated the correlation of regional cerebral blood flow (rCBF) changes and the clinical severity of AD patients. METHODS Thirty-nine AD patients and 16 normal subjects participated in this study. AD patients were divided into three subgroups by clinical severity. Quantitative brain perfusion SPECT analyses were performed using a rCBF quantification software, 3DSRT. RESULTS In mild AD, significant decreases of rCBF were detected in the bilateral parietal, angular gyrus, pericallosal, thalamus, right temporal and left hippocampal regions. Moderate AD patients showed significantly lower blood flow than those with mild AD only to the right hippocampus. Analysis of the severe AD group revealed a nearly diffuse decrease of rCBF throughout the cerebral cortex except for part of the frontal lobe compared with moderate patients. CONCLUSIONS These results were consistent with previous findings demonstrated by qualitative analysis of CBF. The decreased thalamic blood flow was noteworthy as this finding has rarely been reported. In consideration of the structure and function of the Papez circuit, which connects the medial temporal lobe and thalamus, a remote metabolic effect might be the cause of lower rCBF in the thalamus.
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Affiliation(s)
- Seiju Kobayashi
- Department of Psychiatry, Sunagawa City Medical Center, Hokkaido, Japan
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Abstract
There are five potential major roles for neuroimaging with respect to dementia; (1) as a cognitive neuroscience research tool, (2) for prediction of which normal or slightly impaired individuals will develop dementia and over what time frame, (3) for early diagnosis of Alzheimer's disease (AD) in demented individuals, (sensitivity) and separation of AD from other forms of dementia (specificity), (4) for monitoring of disease progression, and (5) for monitoring response to therapies. Focusing on the last role, no single imaging approach is yet ideal, as all trade-off speed, cost, and accuracy. Functional imaging (SPECT and PET) is best suited to tracking symptomatic therapy response, and anatomic (MRI volumetric) imaging or amyloid PET are more suited to reflect dementia modulation studies. The potential for imaging with respect to pharmacological studies of dementia--to provide surrogate markers for drug studies, to improve diagnosis, to speed evaluation of outcomes, and to decrease sample sizes--is huge. At the present time, however, no single measure has sufficient proven reliability, replicability, or robustness, to replace clinical primary outcome measures.
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Affiliation(s)
- Howard Chertkow
- Department of Clinical Neuroscience, Sir Mortimer B. Davis-Jewish General Hospital, Toronto, ON, Canada
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40
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Irving EA, Upton N. Symptomatic treatment of Alzheimer’s disease: identification of biomarkers to aid translation from bench to bedside. Biomark Med 2007; 1:93-110. [DOI: 10.2217/17520363.1.1.93] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In the absence of robust pharmacodynamic markers, the potential success of novel therapeutic agents for the symptomatic relief of Alzheimer’s disease is largely unknown until the drugs enter relatively large studies, assessing clinical outcome over a 6-month period. In order to increase the efficiency of future clinical development there is, therefore, a need to identify pharmacodynamic markers of drug response, pharmacodynamic models that allow early prediction of efficacy and markers to aid the stratification of the patient population. Using literature available from cholinesterase inhibitors, memantine and Ginkgo biloba, this review focuses on the identification of potential pharmacodynamic markers/models and highlights the utility of these end points throughout the drug discovery process, from preclinical to clinical development.
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Affiliation(s)
- Elaine A Irving
- GlaxoSmithKline, Neurology and GI CEDD, New Frontiers Science Park North, Third Avenue, Harlow, Essex, CM19 5AW, UK
| | - Neil Upton
- GlaxoSmithKline, Neurology and GI CEDD, New Frontiers Science Park North, Third Avenue, Harlow, Essex, CM19 5AW, UK
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Abstract
Alzheimer's disease (AD) is the commonest form of degenerative dementia and is characterised by progressive cognitive decline. Despite extensive research, the cause of AD is unknown and there is no cure at present. Of the deficits found in AD, that affecting the cholinergic neurotransmitter system is the best established and the only one translated into symptomatic treatment. Cholinergic enhancement with cholinesterase inhibitor (ChEI) drugs has been achieved and their efficacy and safety ascertained by conventional clinical trials. The mechanism of action of these drugs, however, is not well understood. Imaging with SPECT, PET, MRI and fMRI after treatment has clarified what happens in the brains of those AD patients treated with ChEI drugs. Studies with these techniques have identified increases in brain blood flow and glucose metabolism, restoration of nicotinic receptor function and re-establishment of task-related regional brain activation in response to cognitive stimulation after treatment. Structural MRI studies have explained, to some degree, why only a proportion of patients benefits from ChEI treatment and there is some evidence that some ChEI drugs might be neuroprotective. There are, however, many unsolved problems. Timing of treatment intervention to obtain maximum response and the determinants of treatment response are mostly unknown. It is also unclear whether administration of treatment in those patients who have no potential for response accelerates disease progression. These issues cannot be solved by conventional clinical trials. Pharmacoimaging studies could assist the development and refinement of drugs to treat those diseases, such as AD, which affect the central nervous system.
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Affiliation(s)
- Annalena Venneri
- Clinical Neuroscience Centre, University of Hull, HU6 7RX Hull, UK.
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Shanks MF, McGeown WJ, Forbes-McKay KE, Waiter GD, Ries M, Venneri A. Regional brain activity after prolonged cholinergic enhancement in early Alzheimer's disease. Magn Reson Imaging 2007; 25:848-59. [PMID: 17442521 DOI: 10.1016/j.mri.2007.02.005] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/11/2007] [Indexed: 11/29/2022]
Abstract
This functional magnetic resonance imaging (fMRI) study examined changes in brain activation after prolonged (20 weeks) and stabilized treatment with the cholinesterase inhibitor galantamine in a small group of patients with very mild Alzheimer's disease (AD). Two cognitive activation paradigms were chosen: one requiring semantic association and the other relying on attention and requiring target detection. A group of age- and education-matched healthy controls was also scanned for comparison. A modest (but not statistically significant) improvement in behavioral scores after treatment was observed in both fMRI tasks. There were brain activation increases in the semantic association task after treatment, and the differences in brain activation present in the comparison of AD patients' baseline images with those of controls were not detectable after treatment. In the target detection task, regions that were activated in the elderly controls but not in the baseline images of the AD group also showed significant activation after treatment. Overall, however, the increases were modest and might reflect the heterogeneity of clinical response to treatment in this small group. Future pharmacological fMRI studies should include clinical response as a factor in the analysis of cholinergic enhancement effects in AD patients.
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Affiliation(s)
- Michael F Shanks
- Clinical Neuroscience Centre, University of Hull, HU6 7RX Hull, UK
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43
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Abstract
Vascular cognitive impairment/vascular dementia have been the subject of a large
number of studies, due to their high prevalence and broad preventive and
compensatory therapeutic potential. The knowledge of the cerebral anatomy
correlated to the vascular territories of irrigation enables understanding of
clinical manifestations, as well as classification into the several types of
syndromic presentations. The central cholinergic system exercises important
neuromodulatory functions on cerebral circuits related to cognitive and
behavioral integration, as well as on vasomotor control related to cerebral
blood flow adjustments. The acquisition of data on the anatomy of the
cholinergic pathways, including the localization of the nuclei of the basal
prosencephalon and the routes of their projections, established an important
milestone. The knowledge of the vascular distribution and of the trajectories of
the cholinergic pathways allows identification of the strategic points where a
vascular lesion can cause interruption. The ensuing denervation leads to
cholinergic hypofunction in the involved territories. This information proves
important to better evaluate the sites of vascular lesions, emphasizing their
strategic localizations in relation to the cholinergic pathways, and offering
more robust foundations for treatment aiming at enhancing cholinergic
activity.
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Staessen JA, Richart T, Birkenhäger WH. Less Atherosclerosis and Lower Blood Pressure for a Meaningful Life Perspective With More Brain. Hypertension 2007; 49:389-400. [PMID: 17283254 DOI: 10.1161/01.hyp.0000258151.00728.d8] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Jan A Staessen
- Studies Coordinating Centre, Division of Hypertension and Cardiovascular Rehabilitation, Department of Cardiovascular Diseases, University of Leuven, Leuven, Belgium.
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Oosterman JM, Scherder EJA. Distinguishing between Vascular Dementia and Alzheimer's Disease by Means of the WAIS: A Meta-analysis. J Clin Exp Neuropsychol 2007; 28:1158-75. [PMID: 16840242 DOI: 10.1080/13803390500263543] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
This study was intended to, meta-analytically, review whether the subtests of the Wechsler Adult Intelligence Scale are useful in differentiating between vascular dementia and Alzheimer's disease. We expected the Alzheimer's disease group to outperform the vascular dementia group on those subtests that require executive functions, whereas inferior performance of the Alzheimer's disease patients was expected on memory tests. Two steps in the analysis were undertaken in an attempt to clarify this issue. The first step consisted of including all studies examining Wechsler Adult Intelligence Scale subtest performance in vascular dementia and Alzheimer's disease patients. Secondly, a subcortical vascular dementia subgroup was distinguished and performance of this subgroup was compared to that of the Alzheimer's disease group.Overall, the analyses showed that both the vascular dementia and, more strongly, the subcortical vascular dementia group revealed decreased executive functions on several subtests compared to the Alzheimer's disease group. The Alzheimer's disease group showed inferior performance on a single semantic memory test only compared to both the vascular dementia and the subcortical vascular dementia groups. These results indicate that several subtests of the Wechsler Adult Intelligence Scale can differentiate between these two clinical groups, and that most of these tests reveal more impaired performance in the vascular dementia group.
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Affiliation(s)
- Joukje M Oosterman
- Department of Clinical Neuropsychology, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands.
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46
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Holzgrabe U, Kapková P, Alptüzün V, Scheiber J, Kugelmann E. Targeting acetylcholinesterase to treat neurodegeneration. Expert Opin Ther Targets 2007; 11:161-79. [PMID: 17227232 DOI: 10.1517/14728222.11.2.161] [Citation(s) in RCA: 143] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Neurodegenerative disorders, such as Alzheimer's disease, are often characterised by the degeneration of the cholinergic system. Thus, the aim of many treatment regimens is to support this system either by means of muscarinic agonists or by inhibitors of acetylcholinesterase (AChE), the latter being able to increase the concentration of acetylcholine. However, both pharmacological groups of drugs can only help in the beginning of the progressive disease. The finding that the occupation of the peripheral anionic site of AChE is able to stop the formation of the amyloid plaque led to the development of bivalent ligands that occupy both the active and the peripheral site. This dual action might be more beneficial for treatment of Alzheimer s disease than simple inhibition of the acetylcholine hydrolysis. Thus, the new bivalent ligands are the focus of this review.
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Affiliation(s)
- Ulrike Holzgrabe
- Institute of Pharmacy and Food Chemistry, University of Würzburg, Am Hubland, 97074 Würzburg, Germany.
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Román GC, Kalaria RN. Vascular determinants of cholinergic deficits in Alzheimer disease and vascular dementia. Neurobiol Aging 2006; 27:1769-85. [PMID: 16300856 DOI: 10.1016/j.neurobiolaging.2005.10.004] [Citation(s) in RCA: 149] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2005] [Revised: 09/02/2005] [Accepted: 10/03/2005] [Indexed: 11/18/2022]
Abstract
Alzheimer's disease (AD) and vascular dementia (VaD) are widely accepted as the most common forms of dementia. Cerebrovascular lesions frequently coexist with AD, creating an overlap in the clinical and pathological features of VaD and AD. This review assembles evidence for a role for cholinergic mechanisms in the pathogenesis of VaD, as has been established for AD. We first consider the anatomy and vascularization of the basal forebrain cholinergic neuronal system, emphasizing its susceptibility to the effects of arterial hypertension, sustained hypoperfusion, and ischemic cerebrovascular disease. The impact of aging and consequences of disruption of the cholinergic system in cognition and in control of cerebral blood flow are further discussed. We also summarize preclinical and clinical evidence supporting cholinergic deficits and the use of cholinesterase inhibitors in patients with VaD. We postulate that vascular pathology likely plays a common role in initiating cholinergic neuronal abnormalities in VaD and AD.
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Affiliation(s)
- Gustavo C Román
- University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, USA
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Mueller SG, Schuff N, Weiner MW. Evaluation of treatment effects in Alzheimer's and other neurodegenerative diseases by MRI and MRS. NMR IN BIOMEDICINE 2006; 19:655-68. [PMID: 16986115 PMCID: PMC1820857 DOI: 10.1002/nbm.1062] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Neurodegeneration refers to a large clinically and pathologically heterogeneous disease entity associated with slowly progressive neuronal loss in different anatomical and functional systems of the brain. Neurodegenerative diseases often affect cognition, e.g. Alzheimer's disease (AD), dementia with Lewy bodies and vascular dementia, or different aspects of the motor system, e.g., amyotrophic lateral sclerosis, Parkinson's disease and ataxic disorders. Owing to increasing knowledge about the mechanisms leading to neurodegeneration, the development of treatments able to modify the neurodegenerative process becomes possible for the first time. Currently, clinical outcome measures are used to assess the efficacy of such treatments. However, most clinical outcome measures have a low test-retest reliability and thus considerable measurement variance. Therefore, large patient populations and long observation times are needed to detect treatment effects. Furthermore, clinical outcome measures cannot distinguish between symptomatic and disease-modifying treatment effects. Therefore, alternative biomarkers including neuroimaging may take on a more important role in this process. Because MR scanners are widely available and allow for non-invasive detection and quantification of changes in brain structure and metabolism, there is increasing interest in the use of MRI/MRS to monitor objectively treatment effects in clinical trials of neurodegenerative diseases. Particularly volumetric MRI has been used to measure atrophy rates in treatment trials of AD because the relationship between atrophic changes and neuron loss is well established and correlates well with clinical measures. More research is needed to determine the value of other MR modalities, i.e. diffusion, perfusion and functional MRI and MR spectroscopy, for clinical trials with neuroprotective drugs.
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Affiliation(s)
- S. G. Mueller
- Center of Imaging of Neurodegenerative Diseases, Veterans Administration Medical Center, Department of Radiology, University of California San Francisco, San Francisco, CA 94121, USA
| | - N. Schuff
- Center of Imaging of Neurodegenerative Diseases, Veterans Administration Medical Center, Department of Radiology, University of California San Francisco, San Francisco, CA 94121, USA
| | - M. W. Weiner
- Center of Imaging of Neurodegenerative Diseases, Veterans Administration Medical Center, Department of Radiology, University of California San Francisco, San Francisco, CA 94121, USA
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49
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Asp E, Cloutier F, Fay S, Cook C, Robertson ML, Fisk J, Dei DW, Rockwood K. Verbal repetition in patients with Alzheimer's disease who receive donepezil. Int J Geriatr Psychiatry 2006; 21:426-31. [PMID: 16676290 DOI: 10.1002/gps.1486] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Current outcome measures for Alzheimer's disease (AD) drugs have been criticized as insufficiently patient-centred. One commonly unmeasured goal of patients and caregivers is verbal repetition. OBJECTIVES We examined how often reducing repetition (of questions, statements or stories) was set as treatment goal, whether and when it responded, and how change in repetition correlated with change in other domains. METHODS This is a secondary analysis of the open-label Atlantic Canada Alzheimer's Disease Investigation of Expectations study of donepezil for mild-moderate AD in 100 community-dwelling people. Goal Attainment Scaling, an individualized account of the goals of treatment, was the primary outcome measure. RESULTS Reducing repetition was a treatment goal in 46%, who were not systematically different from others. Of 18 patients in whom repetition improved for 9 months, 83% (15) showed a response at 3 months. Early (3-month) response correlated best with the overall level of goal attainment (r = 0.74) and changes in leisure activities (r = 0.69) and social interactions (r = 0.68) compared with changes in cognition (r = 0.44) or behaviour (r = 0.11). Correlations with the ADAS-Cog and MMSE change scores remained only modest (at 12 months = -0.25 and 0.19, respectively). Correlations with the CIBIC-Plus were higher (-0.47 at 3 months and -0.43 at 12 months). CONCLUSION Diminution of repetition is common, and appears to mark response to cholinesterase inhibition in some patients. Responders generally also show improved cognition and function, perhaps as an aspect of improved executive function.
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Affiliation(s)
- Elissa Asp
- Geriatric Medicine Research Unit, Dalhousie University, Halifax, NS, Canada
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50
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Claassen JAHR, Jansen RWMM. Cholinergically Mediated Augmentation of Cerebral Perfusion in Alzheimer's Disease and Related Cognitive Disorders: The Cholinergic-Vascular Hypothesis. J Gerontol A Biol Sci Med Sci 2006; 61:267-71. [PMID: 16567376 DOI: 10.1093/gerona/61.3.267] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The treatment of Alzheimer's disease (AD) with cholinesterase inhibitors (ChEIs) is based on the cholinergic hypothesis. This hypothesis fails to account for the global nature of the clinical effects of ChEIs, for the replication of these effects in other dementias, and for the strong and unpredictable intraindividual variation in response to treatment. These findings may be better explained by the premise that ChEIs primarily act by augmenting cerebral perfusion: the cholinergic-vascular hypothesis. This article will review the evidence from preclinical and clinical investigations on the vascular role of the cholinergic neural system. The clinical relevance of this hypothesis is discussed with respect to its interactions with the vascular and amyloid hypotheses of AD. Implications for treatment are indicated. Finally, we propose that the role of the cholinergic system in neurovascular regulation and functional hyperemia elucidates how the cholinergic deficit in AD contributes to the clinical and pathological features of this disease.
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Affiliation(s)
- Jurgen A H R Claassen
- Department of Geriatric Medicine, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, The Netherlands.
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