scholarly journals Association of peripheral blood DNA methylation level with Alzheimer’s disease progression

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Qingqin S. Li ◽  
Aparna Vasanthakumar ◽  
Justin W. Davis ◽  
Kenneth B. Idler ◽  
Kwangsik Nho ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Dna Methylation ◽  
Cognitive Decline ◽  
Peripheral Blood ◽  
Rating Scale ◽  
Association Studies ◽  
Clinical Dementia Rating ◽  
Cpg Sites ◽  
Cognition And Learning

Abstract Background Identifying biomarkers associated with Alzheimer’s disease (AD) progression may enable patient enrichment and improve clinical trial designs. Epigenome-wide association studies have revealed correlations between DNA methylation at cytosine-phosphate-guanine (CpG) sites and AD pathology and diagnosis. Here, we report relationships between peripheral blood DNA methylation profiles measured using Infinium® MethylationEPIC BeadChip and AD progression in participants from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) cohort. Results The rate of cognitive decline from initial DNA sampling visit to subsequent visits was estimated by the slopes of the modified Preclinical Alzheimer Cognitive Composite (mPACC; mPACCdigit and mPACCtrailsB) and Clinical Dementia Rating Scale Sum of Boxes (CDR-SB) plots using robust linear regression in cognitively normal (CN) participants and patients with mild cognitive impairment (MCI), respectively. In addition, diagnosis conversion status was assessed using a dichotomized endpoint. Two CpG sites were significantly associated with the slope of mPACC in CN participants (P < 5.79 × 10−8 [Bonferroni correction threshold]); cg00386386 was associated with the slope of mPACCdigit, and cg09422696 annotated to RP11-661A12.5 was associated with the slope of CDR-SB. No significant CpG sites associated with diagnosis conversion status were identified. Genes involved in cognition and learning were enriched. A total of 19, 13, and 5 differentially methylated regions (DMRs) associated with the slopes of mPACCtrailsB, mPACCdigit, and CDR-SB, respectively, were identified by both comb-p and DMRcate algorithms; these included DMRs annotated to HOXA4. Furthermore, 5 and 19 DMRs were associated with conversion status in CN and MCI participants, respectively. The most significant DMR was annotated to the AD-associated gene PM20D1 (chr1: 205,818,956 to 205,820,014 [13 probes], Sidak-corrected P = 7.74 × 10−24), which was associated with both the slope of CDR-SB and the MCI conversion status. Conclusion Candidate CpG sites and regions in peripheral blood were identified as associated with the rate of cognitive decline in participants in the ADNI cohort. While we did not identify a single CpG site with sufficient clinical utility to be used by itself due to the observed effect size, a biosignature composed of DNA methylation changes may have utility as a prognostic biomarker for AD progression.

scholarly journals Predictors of rapid cognitive decline in Alzheimer's disease: results from the Australian Imaging, Biomarkers and Lifestyle (AIBL) study of ageing

2011 ◽  
Vol 24 (2) ◽  
pp. 197-204 ◽  
Author(s):  
Alessandro Sona ◽  
Ping Zhang ◽  
David Ames ◽  
Ashley I. Bush ◽  
Nicola T. Lautenschlager ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Cognitive Decline ◽  
Rating Scale ◽  
Cognitive Status ◽  
Imaging Biomarkers ◽  
Clinical Dementia Rating ◽  
Factors Associated ◽  
Biological Variables ◽  
Rapid Cognitive Decline

ABSTRACTBackground: The AIBL study, which commenced in November 2006, is a two-center prospective study of a cohort of 1112 volunteers aged 60+. The cohort includes 211 patients meeting NINCDS-ADRDA criteria for Alzheimer's disease (AD) (180 probable and 31 possible). We aimed to identify factors associated with rapid cognitive decline over 18 months in this cohort of AD patients.Methods: We defined rapid cognitive decline as a drop of 6 points or more on the Mini-Mental State Examination (MMSE) between baseline and 18-month follow-up. Analyses were also conducted with a threshold of 4, 5, 7 and 8 points, as well as with and without subjects who had died or were too severely affected to be interviewed at 18 months and after, both including and excluding subjects whose AD diagnosis was “possible” AD. We sought correlations between rapid cognitive decline and demographic, clinical and biological variables.Results: Of the 211 AD patients recruited at baseline, we had available data for 156 (73.9%) patients at 18 months. Fifty-one patients were considered rapid cognitive decliners (32.7%). A higher Clinical Dementia Rating scale (CDR) and higher CDR “sum of boxes” score at baseline were the major predictors of rapid cognitive decline in this population. Furthermore, using logistic regression model analysis, patients treated with a cholinesterase inhibitor (CheI) had a higher risk of being rapid cognitive decliners, as did males and those of younger age.Conclusions: Almost one third of patients satisfying established research criteria for AD experienced rapid cognitive decline. Worse baseline functional and cognitive status and treatment with a CheI were the major factors associated with rapid cognitive decline over 18 months in this population.

scholarly journals Association between plasma exosome neurogranin and brain structure in patients with Alzheimer’s disease: a protocol study

BMJ Open ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. e036990 ◽  
Author(s):  
MengFei He ◽  
Li Sun ◽  
Wenhui Cao ◽  
Changhao Yin ◽  
Wenqiang Sun ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Cognitive Decline ◽  
Rating Scale ◽  
Early Stage ◽  
Verbal Learning ◽  
Blood Collection ◽  
Clinical Dementia Rating ◽  
Protocol Study ◽  
Medical University

IntroductionNeurogranin is known to be significantly elevated in patients with Alzheimer’s disease (AD) and may be an effective clinical predictor of cognitive decline and neurodegeneration. Amnestic mild cognitive impairment (aMCI) is an intermediate disease state between normal cognitive ageing and dementia, the latter of which can easily revert to AD. There remains significant uncertainty regarding the conversion of aMCI to AD, and therefore, elucidating such progression is paramount to the field of cognitive neuroscience. In this protocol study, we therefore aim to investigate the changes in plasma neurogranin in the early stage of AD and the mechanism thereof regarding the cognitive progression towards AD.Methods and analysisIn this study, patients with aMCI and AD patients (n=70 each) will be recruited at the memory clinic of the Department of Neurology of Hongqi Hospital affiliated with the Mudanjiang Medical University of China. Healthy older controls (n=70) will also be recruited from the community. All subjects will undergo neuroimaging and neuropsychological evaluations in addition to blood collection at the first year and the third year. We hope to identify a new biomarker of cognitive decline associated with AD and characterise its behaviour throughout the progression of aMCI to AD. This work will reveal novel targets for the therapeutic prevention, diagnosis and treatment of AD. The primary outcome measures will be (1) neuropsychological evaluation, including Mini-Mental State Examination, Montreal Cognitive Assessment, Clinical Dementia Rating scale, Shape Trail Test-A&B, Auditory Verbal Learning Test-HuaShan version; (2) microstructural alterations and hippocampal features from MRI scans; and (3) neurogranin levels in the neuronal-derived exosomes from peripheral blood samples.Ethics and disseminationThe ethics committee of the Hongqi Hospital affiliated with the Mudanjiang Medical University of China has approved this study protocol. The results will be published in peer-reviewed journals and presented at national or international scientific conferences.Trial registration numberChiCTR2000029055.

scholarly journals Longitudinal data in peripheral blood confirm that PM20D1 is a quantitative trait locus (QTL) for Alzheimer’s disease and implicate its dynamic role in disease progression

2020 ◽  
Vol 12 (1) ◽  
Author(s):  
Qi Wang ◽  
Yinghua Chen ◽  
Benjamin Readhead ◽  
Kewei Chen ◽  
Yi Su ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Dna Methylation ◽  
Longitudinal Data ◽  
Disease Progression ◽  
Peripheral Blood ◽  
Early Stage ◽  
Underlying Mechanism ◽  
Methylation Data ◽  
Brain Tissues

Abstract Background While Alzheimer’s disease (AD) remains one of the most challenging diseases to tackle, genome-wide genetic/epigenetic studies reveal many disease-associated risk loci, which sheds new light onto disease heritability, provides novel insights to understand its underlying mechanism and potentially offers easily measurable biomarkers for early diagnosis and intervention. Methods We analyzed whole-genome DNA methylation data collected from peripheral blood in a cohort (n = 649) from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) and compared the DNA methylation level at baseline among participants diagnosed with AD (n = 87), mild cognitive impairment (MCI, n = 175) and normal controls (n = 162), to identify differentially methylated regions (DMRs). We also leveraged up to 4 years of longitudinal DNA methylation data, sampled at approximately 1 year intervals to model alterations in methylation levels at DMRs to delineate methylation changes associated with aging and disease progression, by linear mixed-effects (LME) modeling for the unchanged diagnosis groups (AD, MCI and control, respectively) and U-shape testing for those with changed diagnosis (converters). Results When compared with controls, patients with MCI consistently displayed promoter hypomethylation at methylation QTL (mQTL) gene locus PM20D1. This promoter hypomethylation was even more prominent in patients with mild to moderate AD. This is in stark contrast with previously reported hypermethylation in hippocampal and frontal cortex brain tissues in patients with advanced-stage AD at this locus. From longitudinal data, we show that initial promoter hypomethylation of PM20D1 during MCI and early stage AD is reversed to eventual promoter hypermethylation in late stage AD, which helps to complete a fuller picture of methylation dynamics. We also confirm this observation in an independent cohort from the Religious Orders Study and Memory and Aging Project (ROSMAP) Study using DNA methylation and gene expression data from brain tissues as neuropathological staging (Braak score) advances. Conclusions Our results confirm that PM20D1 is an mQTL in AD and demonstrate that it plays a dynamic role at different stages of the disease. Further in-depth study is thus warranted to fully decipher its role in the evolution of AD and potentially explore its utility as a blood-based biomarker for AD.

scholarly journals Efficacy and Limitations of rCBF-SPECT in the Diagnosis of Alzheimer’s Disease With Amyloid-PET

2019 ◽  
Vol 34 (5) ◽  
pp. 314-321
Author(s):  
Miwako Takahashi ◽  
Tomoko Tada ◽  
Tomomi Nakamura ◽  
Keitaro Koyama ◽  
Toshimitsu Momose
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Rating Scale ◽  
Single Photon ◽  
Photon Emission ◽  
Emission Computed Tomography ◽  
Amyloid Pet ◽  
Clinical Dementia Rating ◽  
Positron Emission ◽  
Rcbf Spect

This study aimed to assess efficacy and limitations of regional cerebral blood flow imaging using single-photon emission computed tomography (rCBF-SPECT) in the diagnosis of Alzheimer’s disease (AD) with amyloid-positron emission tomography (amyloid-PET). Thirteen patients, who underwent both rCBF-SPECT and amyloid-PET after clinical diagnosis of AD or mild cognitive impairment, were retrospectively identified. The rCBF-SPECTs were classified into 4 grades, from typical AD pattern to no AD pattern of hypoperfusion; amyloid-beta (Aβ) positivity was assessed by amyloid-PET. Four patients were categorized into a typical AD pattern on rCBF-SPECT, and all were Aβ+. The other 9 patients did not exhibit a typical AD pattern; however, 4 were Aβ+. The Mini-Mental State Examination score and Clinical Dementia Rating scale were not significantly different between Aβ+ and Aβ– patients. A typical AD pattern on rCBF-SPECT can reflect Aβ+; however, if not, rCBF-SPECT has a limitation to predict amyloid pathology.

scholarly journals Association between DNA Methylation of the BDNF Promoter Region and Clinical Presentation in Alzheimer's Disease

2015 ◽  
Vol 5 (1) ◽  
pp. 64-73 ◽  
Author(s):  
Tomoyuki Nagata ◽  
Nobuyuki Kobayashi ◽  
Jumpei Ishii ◽  
Shunichiro Shinagawa ◽  
Ritsuko Nakayama ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Dna Methylation ◽  
Methylation Level ◽  
Clinical Presentation ◽  
Neuropsychological Test ◽  
Cpg Sites ◽  
The Brain ◽  
Normal Controls ◽  
Methylation Ratio

Background/Aims: In the present study, we examined whether DNA methylation of the brain-derived neurotrophic factor (BDNF) promoter is associated with the manifestation and clinical presentation of Alzheimer's disease (AD). Methods: Of 20 patients with AD and 20 age-matched normal controls (NCs), the DNA methylation of the BDNF promoter (measured using peripheral blood samples) was completely analyzed in 12 patients with AD and 6 NCs. The resulting methylation levels were compared statistically. Next, we investigated the correlation between the DNA methylation levels and the clinical presentation of AD. Results: The total methylation ratio (in %) of the 20 CpG sites was significantly higher in the AD patients (5.08 ± 5.52%) than in the NCs (2.09 ± 0.81%; p < 0.05). Of the 20 CpG sites, the methylation level at the CpG4 site was significantly higher in the AD subjects than in the NCs (p < 0.05). Moreover, the methylation level was significantly and negatively correlated with some neuropsychological test subscores (registration, recall, and prehension behavior scores; p < 0.05). Conclusion: These results suggest that the DNA methylation of the BDNF promoter may significantly influence the manifestation of AD and might be associated with its neurocognitive presentation.

Associations of Blood Pressure with Functional and Cognitive Changes in Patients with Alzheimer's Disease

2016 ◽  
Vol 41 (5-6) ◽  
pp. 314-323 ◽  
Author(s):  
Fabricio Ferreira de Oliveira ◽  
Elizabeth Suchi Chen ◽  
Marilia Cardoso Smith ◽  
Paulo Henrique Ferreira Bertolucci
Keyword(s):  
Alzheimer’S Disease ◽  
Blood Pressure ◽  
Alzheimer's Disease ◽  
Rating Scale ◽  
Late Onset ◽  
Angiotensin Receptor Blockers ◽  
Channel Blockers ◽  
Clinical Dementia Rating ◽  
Cognitive Changes ◽  
Converting Enzyme Inhibitors

Background: Midlife hypertension followed by late life hypotension resulting from neurodegeneration increases amyloidogenesis and tauopathy. Methods: Consecutive outpatients with late-onset Alzheimer's disease (AD) at various stages and their respective caregivers were assessed for score variations in 1 year of tests assessing caregiver burden, functionality and cognition according to blood pressure (BP) variations and APOE haplotypes, while also taking into account differential effects of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, β-blockers, calcium channel blockers, diuretics, or no antihypertensive medication on score changes. The diagnosis and treatment of arterial hypertension followed the JNC 7 report. Results: Variations in systolic BP (-11.76 ± 17.1 mm Hg), diastolic BP (-4.92 ± 10.3 mm Hg) and pulse pressure (-6.84 ± 12.6 mm Hg) were significant after 1 year (n = 191; ρ < 0.01). For APOE4+ carriers, rises in systolic or diastolic BP improved Clinical Dementia Rating Scale Sum of Boxes scores (ρ < 0.04), with marginally significant improvements in Mini-Mental State Examination scores resulting from risen systolic (ρ = 0.069) or diastolic BP (ρ = 0.079), and in basic independence only regarding risen diastolic BP (ρ = 0.055). APOE4- carriers resisted any functional or cognitive effects of BP variations. No differences were found regarding any antihypertensive class for variations in BP or any test scores, regardless of APOE haplotypes. Conclusions: Targeting mild BP elevations brings better functional and cognitive results for APOE4+ carriers with AD.

scholarly journals Functional Genetic Biomarkers of Alzheimer’s Disease and Gene Expression from Peripheral Blood

2021 ◽  
Author(s):  
Andrew Ni ◽  
Amish Sethi ◽  
Keyword(s):  
Gene Expression ◽  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Peripheral Blood ◽  
Genetic Variants ◽  
Cell Activation ◽  
Association Studies ◽  
Gene Set Enrichment Analysis ◽  
Machine Learning Techniques ◽  
Genome Wide Association Studies

AbstractDetecting Alzheimer’s Disease (AD) at the earliest possible stage is key in advancing AD prevention and treatment but is challenged by normal aging processes in addition to other confounding neurodegenerative diseases. Recent genome-wide association studies (GWAS) have identified associated alleles, but it has been difficult to transition from non-coding genetic variants to underlying mechanisms of AD. Here, we sought to reveal functional genetic variants and diagnostic biomarkers underlying AD using machine learning techniques. We first developed a Random Forest (RF) classifier using microarray gene expression data sampled from the peripheral blood of 744 participants in the Alzheimer’s Disease Neuroimaging Initiative (ADNI) cohort. After initial feature selection, 5-fold cross-validation of the 100-gene RF classifier achieved an accuracy of 99.04%. The high accuracy of the RF classifier supports the possibility of a powerful and minimally invasive tool for screening of AD. Next, unsupervised clustering was used to validate and identify relationships among differentially expressed genes (DEGs) the RF selected revealing 3 distinct AD clusters. Results suggest downregulation of global sulfatase and oxidoreductase activities in AD through mutations in SUMF1 and SMOX respectively. Then, we used Greedy Fast Causal Inference (GFCI) to find potential causes of AD within DEGs. In the causal graph, HLA-DPB1 and CYP4A11 emerge as hub genes, furthering the discussion of the immune system’s role in AD. Finally, we used Gene Set Enrichment Analysis (GSEA) to determine the biological pathways and processes underlying the DEGs that were highly correlated with AD. Cell activation in the immune system, glycosaminoglycan (GAG) binding, vascular dysfunction, oxidative stress, and the neuronal apoptotic process were revealed to be significantly enriched in AD. This study further advances the possibility of low-cost and noninvasive genetic screening for AD while also providing potential gene targets for further experimentation.

scholarly journals Benfotiamine and Cognitive Decline in Alzheimer’s Disease: Results of a Randomized Placebo-Controlled Phase IIa Clinical Trial

2020 ◽  
Vol 78 (3) ◽  
pp. 989-1010
Author(s):  
Gary E. Gibson ◽  
José A. Luchsinger ◽  
Rosanna Cirio ◽  
Huanlian Chen ◽  
Jessica Franchino-Elder ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Placebo Group ◽  
Cognitive Decline ◽  
Controlled Trial ◽  
Amyloid Β ◽  
Cognitive Outcomes ◽  
Disease Assessment ◽  
Clinical Dementia Rating ◽  
Positron Emission

Background: In preclinical models, benfotiamine efficiently ameliorates the clinical and biological pathologies that define Alzheimer’s disease (AD) including impaired cognition, amyloid-β plaques, neurofibrillary tangles, diminished glucose metabolism, oxidative stress, increased advanced glycation end products (AGE), and inflammation. Objective: To collect preliminary data on feasibility, safety, and efficacy in individuals with amnestic mild cognitive impairment (aMCI) or mild dementia due to AD in a placebo-controlled trial of benfotiamine. Methods: A twelve-month treatment with benfotiamine tested whether clinical decline would be delayed in the benfotiamine group compared to the placebo group. The primary clinical outcome was the Alzheimer’s Disease Assessment Scale-Cognitive Subscale (ADAS-Cog). Secondary outcomes were the clinical dementia rating (CDR) score and fluorodeoxyglucose (FDG) uptake, measured with brain positron emission tomography (PET). Blood AGE were examined as an exploratory outcome. Results: Participants were treated with benfotiamine (34) or placebo (36). Benfotiamine treatment was safe. The increase in ADAS-Cog was 43% lower in the benfotiamine group than in the placebo group, indicating less cognitive decline, and this effect was nearly statistically significant (p = 0.125). Worsening in CDR was 77% lower (p = 0.034) in the benfotiamine group compared to the placebo group, and this effect was stronger in the APOE ɛ4 non-carriers. Benfotiamine significantly reduced increases in AGE (p = 0.044), and this effect was stronger in the APOE ɛ4 non-carriers. Exploratory analysis derivation of an FDG PET pattern score showed a treatment effect at one year (p = 0.002). Conclusion: Oral benfotiamine is safe and potentially efficacious in improving cognitive outcomes among persons with MCI and mild AD.

scholarly journals Education, leisure activities and cognitive and functional ability of Alzheimer's disease patients: A follow-up study

2013 ◽  
Vol 7 (2) ◽  
pp. 181-189 ◽  
Author(s):  
Margarida Sobral ◽  
Constança Paúl
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Disease Progression ◽  
Functional Ability ◽  
Rating Scale ◽  
Leisure Activities ◽  
Functional Decline ◽  
Clinical Dementia Rating ◽  
High Participation ◽  
Relevant Variables

ABSTRACT Education and participation in leisure activities appear to be highly relevant variables in Alzheimer's disease (AD) and usually form the basis of the Cognitive Reserve construct. Objective: [A] To determine the association between education, cognitive and functional ability of AD patients; [B] To determine the association between participation in leisure activities and cognitive and functional ability of AD patients; [C] To evaluate the association of education and participation in leisure activities in the course of AD. Methods: Functional and neuropsychological abilities of 120 outpatients with probable AD were evaluated at baseline, at 36 and 54 months. Data collected at baseline included socio-demographics, clinical variables, education and frequency of participation in leisure activities throughout life. All participants and/or caregivers answered the questionnaire, "Participation in leisure activities throughout life" while patients completed the MMSE, the Clinical Dementia Rating scale, neuropsychological tests from the Lisbon Screening for Dementia Assessment, Barthel Index and Lawton and Brody's Index. Results: AD patients with higher levels of education achieved better results on cognitive tests. The participants with higher participation in leisure activities exhibited better results on cognitive and functional tests than those with lower participation. The disease progression was linear and progressed similarly regardless of the level of education of participants. However, the results suggest a slower disease progression in patients with a higher level of participation in leisure activities throughout their lives. Conclusion: AD patients with high education and high participation in leisure activities may benefit from a slower cognitive and functional decline after diagnosis of AD.

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