The Precuneus – A Witness for Excessive Aβ Gathering in Alzheimer’s Disease Pathology

2018 ◽  
Vol 18 (5-6) ◽  
pp. 302-309 ◽  
Author(s):  
Gayane Aghakhanyan ◽  
Andrea Vergallo ◽  
Marta Gennaro ◽  
Sara Mazzarri ◽  
Federica Guidoccio ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Disease Duration ◽  
Standardized Uptake Value ◽  
Positive Association ◽  
Analysis Of Covariance ◽  
Qualitative Assessment ◽  
Control Group ◽  
Positron Emission

Evidence of cortical beta-amyloid (Aβ) load, assessed by Aβ positron emission tomography (Aβ-PET), is an established in vivo biomarker of Alzheimer’s disease (AD)-related pathophysiology. Qualitative assessment of Aβ-PET provides binary information; meanwhile semiquantitative approaches require a parcellation of PET image either manually or by placement of atlas-based volumes of interest. We supposed that a whole-brain approach with voxel-by-voxel standardized uptake value ratio (SUVr) parametric images may better elucidate the spatial trajectories of Aβ burden along the continuum of AD. Methods: We recruited 32 subjects with a diagnosis of probable AD dementia (ADD, n = 20) and mild cognitive impairment due to AD (MCI-AD, n = 12) according to the NIA-AA 2011 criteria. We also enrolled a control group of 6 cognitively healthy individuals (HCs) with preserved cognitive functions and negative Aβ-PET scan. The PET images were spatially normalized using the AV45 PET template in the MNI brain space. Subsequently, parametric SUVr images were calculated using the whole cerebellum as a reference region. A voxel-wise analysis of covariance was used to compare (between groups) the Αβ distribution pattern considering age as a nuisance covariate. Results: Both ADD and MCI-AD subjects showed a widespread increase in radiotracer uptake when compared with HC participants (p < 0.001, uncorrected). After applying a multiple comparison correction (p < 0.05, corrected), a relative large cluster of increased [18F]-flor­betapir uptake was observed in the precuneus in the ADD and MCI-AD groups compared to HCs. Voxel-wise regression analysis showed a significant positive linear association between the voxel-wise SUVr values and the disease duration. Conclusions: The voxel-wise semiquantitative analysis shows that the precuneus is a region with higher vulnerability to Aβ depositions when compared to other cortical regions in both MCI-AD and ADD subjects. We think that the precuneus is a promising PET-based outcome measure for clinical trials of drugs targeting brain Aβ. We found a positive association between the overall Aβ-PET SUVr and the disease duration suggesting that the region-specific slow saturation of Aβ deposition continuously takes place as the disease progresses.

Season of Birth and Vulnerability to the Pathology of Alzheimer’s Disease: an in Vivo Positron Emission Tomography Study

2021 ◽  
Author(s):  
Fumihiko Yasuno ◽  
Hiroyuki Minami
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Positron Emission Tomography ◽  
Amyloid Β ◽  
Standardized Uptake Value ◽  
Analysis Of Covariance ◽  
Emission Tomography ◽  
Disease Assessment ◽  
Positron Emission

Abstract This study used positron emission tomography to examine whether the seasonal birth effect as an exogenic indicator of early life environmental factors influenced vulnerability to Alzheimer’s disease (AD) pathology in the elderly. We analyzed datasets from the Alzheimer’s Disease Neuroimaging Initiative, which included the data for 234 cognitively normal individuals and patients with mild cognitive impairment (n = 115) and AD dementia (n = 38). As an index of amyloid β (Aβ)/tau accumulation, the AV-45/AV-1451-standardized uptake value ratios (SUVRs) were compared between groups of spring-to-summer births and fall-to-winter births by analysis of covariance. Seasonal birth difference was a good predictor of AV-1451 SUVR. We found that participants with a fall-to-winter birth showed lower AV-1451 SUVRs than those with a spring-to-summer birth, after accounting for the Alzheimer’s Disease Assessment Scale-cognitive subscale (ADAS) score and other factors that could possibly affect tau accumulation. Our findings showed a vulnerability to tau pathology in participants with a fall-to-winter birth, which may be caused by perinatal or postnatal brain damage due to the risk factors associated with the cold season.

Associations of Neprilysin Activity in CSF with Biomarkers for Alzheimer’s Disease

2019 ◽  
Vol 19 (1) ◽  
pp. 43-50 ◽  
Author(s):  
Timo Grimmer ◽  
Oliver Goldhardt ◽  
Igor Yakushev ◽  
Marion Ortner ◽  
Christian Sorg ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Fdg Pet ◽  
Amyloid Β ◽  
Neuronal Injury ◽  
Pittsburgh Compound B ◽  
Positron Emission ◽  
Amyloid Load ◽  
Alzheimer’S Pathology

Background: Neprilysin (NEP) cleaves amyloid-β 1–42 (Aβ42) in the brain. Hence, we aimed to elucidate the effect of NEP on Aβ42 in cerebrospinal fluid (CSF) and on in vivo brain amyloid load using amyloid positron emission tomography (PET) with [11C]PiB (Pittsburgh compound B). In addition, associations with the biomarkers for neuronal injury, CSF-tau and FDG-PET, were investigated. Methods: Associations were calculated using global and voxel-based (SPM8) linear regression analyses in the same cohort of 23 highly characterized Alzheimer’s disease patients. Results: CSF-NEP was significantly inversely associated with CSF-Aβ42 and positively with the extent of neuronal injury as measured by CSF-tau and FDG-PET. Conclusions: Our results on CSF-NEP are compatible with the assumption that local degradation, amongst other mechanisms of amyloid clearance, plays a role in the development of Alzheimer’s pathology. In addition, CSF-NEP is associated with the extent and the rate of neurodegeneration.

scholarly journals In vivo imaging of synaptic loss in Alzheimer’s disease with [18F]UCB-H positron emission tomography

2019 ◽  
Vol 47 (2) ◽  
pp. 390-402 ◽  
Author(s):  
Christine Bastin ◽  
Mohamed Ali Bahri ◽  
François Meyer ◽  
Marine Manard ◽  
Emma Delhaye ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Positron Emission Tomography ◽  
In Vivo Imaging ◽  
Emission Tomography ◽  
Synaptic Loss ◽  
Positron Emission

IC-P-024: A novel positron emission tomography contrast agent targeting cathepsin d shows preferential in vivo retention in an Alzheimer's disease mouse model

2015 ◽  
Vol 11 (7S_Part_1) ◽  
pp. P26-P27
Author(s):  
Jonatan A. Snir ◽  
Mojmir Suchy ◽  
Geron A. Bindseil ◽  
Blaine A. Chronik ◽  
Robert H.E. Hudson ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Positron Emission Tomography ◽  
Mouse Model ◽  
Contrast Agent ◽  
Cathepsin D ◽  
Emission Tomography ◽  
Positron Emission

O1-02-05: A novel positron emission tomography contrast agent targeting cathepsin d shows preferential in vivo retention in an Alzheimer's disease mouse model

2015 ◽  
Vol 11 (7S_Part_3) ◽  
pp. P128-P128
Author(s):  
Jonatan A. Snir ◽  
Mojmir Suchy ◽  
Geron A. Bindseil ◽  
Blaine A. Chronik ◽  
Robert H.E. Hudson ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Positron Emission Tomography ◽  
Mouse Model ◽  
Contrast Agent ◽  
Cathepsin D ◽  
Emission Tomography ◽  
Positron Emission

scholarly journals Prospective longitudinal atrophy in Alzheimer’s disease correlates with the intensity and topography of baseline tau-PET

2020 ◽  
Vol 12 (524) ◽  
pp. eaau5732 ◽  
Author(s):  
Renaud La Joie ◽  
Adrienne V. Visani ◽  
Suzanne L. Baker ◽  
Jesse A. Brown ◽  
Viktoriya Bourakova ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Amyloid Pet ◽  
Specific Distribution ◽  
Positron Emission ◽  
Pet Radiotracers ◽  
Β Amyloid ◽  
Tau Pet ◽  
Prospective Longitudinal

β-Amyloid plaques and tau-containing neurofibrillary tangles are the two neuropathological hallmarks of Alzheimer’s disease (AD) and are thought to play crucial roles in a neurodegenerative cascade leading to dementia. Both lesions can now be visualized in vivo using positron emission tomography (PET) radiotracers, opening new opportunities to study disease mechanisms and improve patients’ diagnostic and prognostic evaluation. In a group of 32 patients at early symptomatic AD stages, we tested whether β-amyloid and tau-PET could predict subsequent brain atrophy measured using longitudinal magnetic resonance imaging acquired at the time of PET and 15 months later. Quantitative analyses showed that the global intensity of tau-PET, but not β-amyloid–PET, signal predicted the rate of subsequent atrophy, independent of baseline cortical thickness. Additional investigations demonstrated that the specific distribution of tau-PET signal was a strong indicator of the topography of future atrophy at the single patient level and that the relationship between baseline tau-PET and subsequent atrophy was particularly strong in younger patients. These data support disease models in which tau pathology is a major driver of local neurodegeneration and highlight the relevance of tau-PET as a precision medicine tool to help predict individual patient’s progression and design future clinical trials.

scholarly journals Combined Study of Cerebral Glucose Metabolism and [11C]Methionine Accumulation in Probable Alzheimer's Disease Using Positron Emission Tomography

1996 ◽  
Vol 16 (3) ◽  
pp. 399-408 ◽  
Author(s):  
E. Salmon ◽  
M. C. Gregoire ◽  
G. Delfiore ◽  
C. Lemaire ◽  
C. Degueldre ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Positron Emission Tomography ◽  
Glucose Metabolism ◽  
Clinical Symptoms ◽  
Synaptic Activity ◽  
Emission Tomography ◽  
Tissue Loss ◽  
Positron Emission

There is a characteristic decrease in glucose metabolism in associative frontal and temporo-parietal cortices of patients suffering from Alzheimer's disease (AD). The decrease in metabolism might result from local neuronal loss or from a decrease of synaptic activity. We measured in vivo [11C]methionine accumulation into proteins with positron emission tomography (PET) to assess cortical tissue loss in AD. Both global regional activity and compartmental analysis were used to express [11C]methionine accumulation into brain tissue. Glucose metabolism was measured with [18F]fluorodeoxyglucose and autoradiographic method. Combined studies were performed in 10 patients with probable AD, compared to age-matched healthy volunteers. There was a significant 45% decrease of temporo-parietal glucose metabolism in patients with AD, and frontal metabolism was lowered in most patients. Temporo-parietal metabolism correlated to dementia severity. [11C]methionine incorporation into temporo-parietal and frontal cortices was not significantly decreased in AD. There was no correlation with clinical symptoms. Data suggest that regional tissue loss, assessed by the decrease of [11C]methionine accumulation, is not sufficient to explain cortical glucose hypometabolism, which reflects, rather, reduced synaptic connectivity.

Amyloid imaging in Alzheimer’s disease: a potential new era of personalized medicine?

2014 ◽  
Vol 5 (1) ◽  
Author(s):  
Antoine Leuzy ◽  
Eduardo Zimmer ◽  
Serge Gauthier ◽  
Pedro Rosa-Neto
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Personalized Medicine ◽  
Amyloid Imaging ◽  
Phase Iii ◽  
Diagnostic Process ◽  
European Medicines Agency ◽  
Amyloid Pet ◽  
Positron Emission

AbstractRecent advances along clinical and neuropathological lines, as well as in our ability to detect the deposition of β-amyloid (Aβ) in vivo using positron emission tomography (PET), have helped redefine Alzheimer’s disease (AD) as a dynamic clinicobiological entity. On the basis of these advances, AD is now conceptualized as a continuum comprising asymptomatic, minimally symptomatic, and dementia phases, with detection of brain Aβ — in particular, via PET amyloid imaging — central to the diagnostic process. In this respect, [18F]florbetapir (Amyvid™) and [18F]flutemetamol (Vizamyl™) have recently received approval for clinical use from the Food and Drug Administration (FDA) and the European Medicines Agency (EMA), with additional radiofluorinated tracers for detection of Aβ in phase III trials. Recent initiatives such as the Alzheimer’s Disease Neuroimaging Initiative (ADNI) suggest that Aβ production, oligomerization and aggregation begins many years, possibly decades, before detectable cognitive impairment, with Aβ shown to associate with cognitive decline and conversion to dementia. While personalized medicine has now emerged as a prospect for the field, the recent decision by the Centers for Medicare & Medicaid Services (CMS) — who declined to cover the cost of amyloid PET imaging citing insufficient evidence to support its clinical utility — highlights that such a move may be premature.

scholarly journals Association of Carotid and Intracranial Stenosis with Alzheimer’s Disease Biomarkers

2020 ◽  
Author(s):  
Koung Mi Kang ◽  
Min Soo Byun ◽  
Jun Ho Lee ◽  
Dahyun Yi ◽  
Hye Jeong Choi ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Hippocampal Volume ◽  
Artery Stenosis ◽  
Intracranial Artery ◽  
Positron Emission ◽  
Intracranial Artery Stenosis ◽  
Intracranial Arteries ◽  
Demographic Covariates

Abstract Background To clarify whether atherosclerosis of the carotid and intracranial arteries is related to Alzheimer’s disease (AD) pathology in vivo, we investigated the associations of carotid and intracranial artery stenosis with cerebral beta-amyloid (Aβ) deposition and neurodegeneration in middle- and old-aged individuals. Given the differential progression of Aβ deposition and neurodegeneration across clinical stages of AD, we focused separately on cognitively normal (CN) and cognitively impaired (CI) groups.Methods A total of 281 CN and 199 CI (mild cognitive impairment and AD dementia) subjects underwent comprehensive clinical assessment, [11C] Pittsburgh Compound B positron emission tomography, and magnetic resonance (MR) imaging including MR angiography. We evaluated extracranial carotid and intracranial arteries for the overall presence, severity (i.e. number and degree of narrowing) and location of stenosis.Results We found no associations between carotid and intracranial artery stenosis and cerebral Aβ burden in either CN or CI group. In terms of AD-related neurodegeneration, exploratory univariate analyses showed associations between the presence and severity of stenosis and neurodegeneration biomarkers of AD (i.e. reduced hippocampal volume [HV] and cortical thickness in the AD-signature regions) in both CN and CI groups. In confirmatory multivariate analyses controlling for demographic covariates and diagnosis, the association between number of stenotic intracranial arteries ≥ 2 and reduced HV in the CI group remained significant.Conclusions Neither carotid nor intracranial artery stenosis appears to be associated with brain Aβ burden, while intracranial artery stenosis is related to amyloid-independent neurodegeneration, particularly hippocampal atrophy. These observations support the importance of proper management of intracranial artery stenosis for delaying the progression of AD neurodegeneration and related cognitive decline.

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