1
|
Bousiges O, Cretin B, Muller C, Botzung A, Sanna L, Anthony P, Philippi N, Demuynck C, Blanc F. Involvement of ApoE4 in dementia with Lewy bodies in the prodromal and demented stages: evaluation of the Strasbourg cohort. GeroScience 2024; 46:1527-1542. [PMID: 37653269 PMCID: PMC10828291 DOI: 10.1007/s11357-023-00883-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 07/19/2023] [Indexed: 09/02/2023] Open
Abstract
ApoE4 as a risk factor for dementia with Lewy bodies (DLB) is still an issue. We sought to determine the involvement of ApoE4 according to different clinical parameters in our cohort of patients from Strasbourg, France. ApoE genotyping was performed on the AlphaLewyMA cohort. In this cohort, 197 patients were genotyped: 105 DLB patients, 37 Alzheimer's disease (AD) patients, 29 patients with AD/DLB comorbidity, and 26 control subjects (CS). The groups of patients were also classified according to the stage of evolution of the disease: prodromal or demented. We analyzed other parameters in relation to ApoE4 status, such as years of education (YOE) and Alzheimer CSF biomarkers. We observed a higher proportion of ApoE4 carriers in the AD (51.4%) and AD/DLB (72.4%) groups compared to the DLB (25.7%) and CS (11.5%) groups (p < 0.0001). We found a correlation between age at disease onset and YOE in the AD group (p = 0.039) but not in the DLB group (p = 0.056). Interestingly, in the DLB group, the subgroup of patients with high YOE (≥ 11) had significantly more patients with ApoE4 than the subgroup with low YOE (< 11). AD biomarkers did not seem to be impacted by the presence of ApoE4, except for Aβ42: DLB ApoE4-positive demented patients showed a more marked Aβ42 decrease. ApoE4 does not appear to be a risk factor for "pure" DLB patients. These results suggest a strong link between ApoE4 and amyloidopathy and consequently with AD. Trial registration: AlphaLewyMa, Identifier: NCT01876459, date of registration: June 12, 2013.
Collapse
Affiliation(s)
- Olivier Bousiges
- ICube Laboratory UMR 7357 and FMTS (Fédération de Médecine Translationnelle de Strasbourg), IMIS Team and IMAGeS Team, University of Strasbourg and CNRS, Strasbourg, France.
- Laboratory of Biochemistry and Molecular Biology, University Hospital of Strasbourg, Strasbourg, France.
| | - Benjamin Cretin
- ICube Laboratory UMR 7357 and FMTS (Fédération de Médecine Translationnelle de Strasbourg), IMIS Team and IMAGeS Team, University of Strasbourg and CNRS, Strasbourg, France
- CM2R (Research and Resources Memory Center), Geriatrics Department, Geriatric Day Hospital, Neurogeriatric Service, University Hospital of Strasbourg, Strasbourg, France
| | - Candice Muller
- CM2R (Research and Resources Memory Center), Geriatrics Department, Geriatric Day Hospital, Neurogeriatric Service, University Hospital of Strasbourg, Strasbourg, France
| | - Anne Botzung
- ICube Laboratory UMR 7357 and FMTS (Fédération de Médecine Translationnelle de Strasbourg), IMIS Team and IMAGeS Team, University of Strasbourg and CNRS, Strasbourg, France
- CM2R (Research and Resources Memory Center), Geriatrics Department, Geriatric Day Hospital, Neurogeriatric Service, University Hospital of Strasbourg, Strasbourg, France
| | - Lea Sanna
- CM2R (Research and Resources Memory Center), Geriatrics Department, Geriatric Day Hospital, Neurogeriatric Service, University Hospital of Strasbourg, Strasbourg, France
| | - Pierre Anthony
- CM2R, Neuropsychology Unit, Head and Neck Department, Neurology Department, University of Strasbourg, Strasbourg, France
- CM2R, Geriatrics Department and Neurology Department, Colmar General Hospital, Colmar, France
| | - Nathalie Philippi
- ICube Laboratory UMR 7357 and FMTS (Fédération de Médecine Translationnelle de Strasbourg), IMIS Team and IMAGeS Team, University of Strasbourg and CNRS, Strasbourg, France
- CM2R, Neuropsychology Unit, Head and Neck Department, Neurology Department, University of Strasbourg, Strasbourg, France
| | - Catherine Demuynck
- CM2R (Research and Resources Memory Center), Geriatrics Department, Geriatric Day Hospital, Neurogeriatric Service, University Hospital of Strasbourg, Strasbourg, France
| | - Frédéric Blanc
- ICube Laboratory UMR 7357 and FMTS (Fédération de Médecine Translationnelle de Strasbourg), IMIS Team and IMAGeS Team, University of Strasbourg and CNRS, Strasbourg, France
- CM2R (Research and Resources Memory Center), Geriatrics Department, Geriatric Day Hospital, Neurogeriatric Service, University Hospital of Strasbourg, Strasbourg, France
| |
Collapse
|
2
|
Palmer JM, Huentelman M, Ryan L. More than just risk for Alzheimer's disease: APOE ε4's impact on the aging brain. Trends Neurosci 2023; 46:750-763. [PMID: 37460334 DOI: 10.1016/j.tins.2023.06.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 05/16/2023] [Accepted: 06/12/2023] [Indexed: 08/18/2023]
Abstract
The apolipoprotein ε4 (APOE ε4) allele is most commonly associated with increased risk for late-onset Alzheimer's disease (AD). However, recent longitudinal studies suggest that these risks are overestimated; most ε4 carriers will not develop dementia in their lifetime. In this article, we review new evidence regarding the impact of APOE ε4 on cognition among healthy older adults. We discuss emerging work from animal models suggesting that ε4 impacts brain structure and function in multiple ways that may lead to age-related cognitive impairment, independent from AD pathology. We discuss the importance of taking an individualized approach in future studies by incorporating biomarkers and neuroimaging methods that may better disentangle the phenotypic influences of APOE ε4 on the aging brain from prodromal AD pathology.
Collapse
Affiliation(s)
- Justin M Palmer
- The University of Arizona, Tucson, AZ, USA; Arizona Alzheimer's Consortium, Phoenix, AZ, USA.
| | - Matthew Huentelman
- Translational Genomics Research Institute, Phoenix, AZ, USA; Arizona Alzheimer's Consortium, Phoenix, AZ, USA
| | - Lee Ryan
- The University of Arizona, Tucson, AZ, USA; Arizona Alzheimer's Consortium, Phoenix, AZ, USA.
| |
Collapse
|
3
|
Pluck G. The Misguided Veneration of Averageness in Clinical Neuroscience: A Call to Value Diversity over Typicality. Brain Sci 2023; 13:860. [PMID: 37371340 DOI: 10.3390/brainsci13060860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 05/16/2023] [Accepted: 05/25/2023] [Indexed: 06/29/2023] Open
Abstract
Research and practice in clinical neurosciences often involve cognitive assessment. However, this has traditionally used a nomothetic approach, comparing the performance of patients to normative samples. This method of defining abnormality places the average test performance of neurologically healthy individuals at its center. However, evidence suggests that neurological 'abnormalities' are very common, as is the diversity of cognitive abilities. The veneration of central tendency in cognitive assessment, i.e., equating typicality with healthy or ideal, is, I argue, misguided on neurodiversity, bio-evolutionary, and cognitive neuroscientific grounds. Furthermore, the use of average performance as an anchor point for normal performance is unreliable in practice and frequently leads to the mischaracterization of cognitive impairments. Examples are explored of how individuals who are already vulnerable for socioeconomic reasons can easily be over-pathologized. At a practical level, by valuing diversity rather than typicality, cognitive assessments can become more idiographic and focused on change at the level of the individual. The use of existing methods that approach cognitive assessment ideographically is briefly discussed, including premorbid estimation methods and informant reports. Moving the focus away from averageness to valuing diversity for both clinical cognitive assessments and inclusion of diverse groups in research is, I argue, a more just and effective way forward for clinical neurosciences.
Collapse
Affiliation(s)
- Graham Pluck
- Clinical Cognitive Sciences Laboratory, Faculty of Psychology, Chulalongkorn University, Borommaratchachonnani Srisattaphat Building, 254 Phayathai Road, Bangkok 10330, Thailand
| |
Collapse
|
4
|
Liu JY, Ma LZ, Wang J, Cui XJ, Sheng ZH, Fu Y, Li M, Ou YN, Yu JT, Tan L, Lian Y. Age-Related Association Between APOE ɛ4 and Cognitive Progression in de novo Parkinson's Disease. J Alzheimers Dis 2023; 91:1121-1132. [PMID: 36565124 DOI: 10.3233/jad-220976] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND APOE ɛ4 genotype was correlated with exacerbation of pathology and higher risk of dementia in Parkinson's disease (PD). Meanwhile, the differential influence of APOE ɛ4 on cognition in young and old individuals interpreted as antagonistic pleiotropy. OBJECTIVE To examine whether the effect of APOE ɛ4 on cognitive progression in de novo PD is age dependent. METHODS In this study, 613 de novo PD patients were recruited from Parkinson's Progression Markers Initiative (PPMI). To examine the age-dependent relationship between APOE ɛ4 and cognitive changes, we added 3-way interaction of APOE ɛ4*baseline age*time to the linear mixed-effect (LME) models and evaluated the specific roles of APOE ɛ4 in the middle age group and elderly group separately. Cox regression was utilized to examine the progression of cognition in age-stratified PD participants. RESULTS Age significantly modified relationship between APOE ɛ4 and cognitive changes in most cognitive domains (pinteraction <0.05). In the elderly group, APOE ɛ4 carriers showed steeper decline in global cognition (p = 0.001) as well as in most cognitive domains, and they had a greater risk of cognitive progression (adjusted HR 1.625, 95% CI 1.143-2.310, p = 0.007), compared with non-carriers. However, in the middle age group, no significant relationships between APOE ɛ4 and cognitive decline can be detected. CONCLUSION Our results indicated that the APOE ɛ4 allele has an age-dependent effect on cognitive decline in PD patients. The underlying mechanisms need to be investigated in the future.
Collapse
Affiliation(s)
- Jia-Yao Liu
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China
| | - Ling-Zhi Ma
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China
| | - Jun Wang
- Chongqing Key Laboratory of Ageing and Brain Diseases, Chongqing, China.,Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, Chongqing, China
| | - Xin-Jing Cui
- Department of Outpatient, Qingdao Municipal Hospital, Qingdao, China
| | - Ze-Hu Sheng
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China
| | - Yan Fu
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China
| | - Meng Li
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China
| | - Ya-Nan Ou
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China
| | - Jin-Tai Yu
- Department of Neurology and Institute of Neurology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Lan Tan
- Department of Neurology, Qingdao Municipal Hospital, Qingdao University, Qingdao, China
| | - Yan Lian
- Chongqing Key Laboratory of Ageing and Brain Diseases, Chongqing, China.,Department of Prevention and Health Care, Daping Hospital, Third Military Medical University, Chongqing, China
| |
Collapse
|
5
|
O’Shea DM, Galvin JE. Female APOE ɛ4 Carriers with Slow Rates of Biological Aging Have Better Memory Performances Compared to Female ɛ4 Carriers with Accelerated Aging. J Alzheimers Dis 2023; 92:1269-1282. [PMID: 36872781 PMCID: PMC10535361 DOI: 10.3233/jad-221145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/06/2023]
Abstract
BACKGROUND Evidence suggests that APOE ɛ4 carriers have worse memory performances compared to APOE ɛ4 non-carriers and effects may vary by sex and age. Estimates of biological age, using DNA methylation may enhance understanding of the associations between sex and APOE ɛ4 on cognition. OBJECTIVE To investigate whether associations between APOE ɛ4 status and memory vary according to rates of biological aging, using a DNA methylation age biomarker, in older men and women without dementia. METHODS Data were obtained from 1,771 adults enrolled in the 2016 wave of the Health and Retirement Study. A series of ANCOVAs were used to test the interaction effects of APOE ɛ4 status and aging rates (defined as 1 standard deviation below (i.e., slow rate), or above (i.e., fast rate) their sex-specific mean rate of aging on a composite measure of verbal learning and memory. RESULTS APOE ɛ4 female carriers with slow rates of GrimAge had significantly better memory performances compared to fast and average aging APOE ɛ4 female carriers. There was no effect of aging group rate on memory in the female non-carriers and no significant differences in memory according to age rate in either male APOE ɛ4 carriers or non-carriers. CONCLUSION Slower rates of aging in female APOE ɛ4 carriers may buffer against the negative effects of the ɛ4 allele on memory. However, longitudinal studies with larger sample sizes are needed to evaluate risk of dementia/memory impairment based on rates of aging in female APOE ɛ4 carriers.
Collapse
Affiliation(s)
- Deirdre M. O’Shea
- Department of Neurology, Comprehensive Center for Brain Health, University of Miami Miller School of Medicine, Boca Raton, FL, USA
| | - James E. Galvin
- Department of Neurology, Comprehensive Center for Brain Health, University of Miami Miller School of Medicine, Boca Raton, FL, USA
| |
Collapse
|
6
|
Atherton K, Han X, Chung J, Cherry JD, Baucom Z, Saltiel N, Nair E, Abdolmohammadi B, Uretsky M, Khan MM, Shea C, Durape S, Martin BM, Palmisano JN, Farrell K, Nowinski CJ, Alvarez VE, Dwyer B, Daneshvar DH, Katz DI, Goldstein LE, Cantu RC, Kowall NW, Alosco ML, Huber BR, Tripodis Y, Crary JF, Farrer L, Stern RA, Stein TD, McKee AC, Mez J. Association of APOE Genotypes and Chronic Traumatic Encephalopathy. JAMA Neurol 2022; 79:787-796. [PMID: 35759276 PMCID: PMC9237800 DOI: 10.1001/jamaneurol.2022.1634] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Importance Repetitive head impact (RHI) exposure is the chief risk factor for chronic traumatic encephalopathy (CTE). However, the occurrence and severity of CTE varies widely among those with similar RHI exposure. Limited evidence suggests that the APOEε4 allele may confer risk for CTE, but previous studies were small with limited scope. Objective To test the association between APOE genotype and CTE neuropathology and related endophenotypes. Design, Setting, and Participants This cross-sectional genetic association study analyzed brain donors from February 2008 to August 2019 from the Veterans Affairs-Boston University-Concussion Legacy Foundation Brain Bank. All donors had exposure to RHI from contact sports or military service. All eligible donors were included. Analysis took place between June 2020 and April 2022. Exposures One or more APOEε4 or APOEε2 alleles. Main Outcomes and Measures CTE neuropathological status, CTE stage (0-IV), semiquantitative phosphorylated tau (p-tau) burden in 11 brain regions (0-3), quantitative p-tau burden in the dorsolateral frontal lobe (log-transformed AT8+ pixel count per mm2), and dementia. Results Of 364 consecutive brain donors (100% male; 53 [14.6%] self-identified as Black and 311 [85.4%] as White; median [IQR] age, 65 [47-77] years) 20 years or older, there were 294 individuals with CTE and 70 controls. Among donors older than 65 years, APOEε4 status was significantly associated with CTE stage (odds ratio [OR], 2.34 [95% CI, 1.30-4.20]; false discovery rate [FDR]-corrected P = .01) and quantitative p-tau burden in the dorsolateral frontal lobe (β, 1.39 [95% CI, 0.83-1.94]; FDR-corrected P = 2.37 × 10-5). There was a nonsignificant association between APOEε4 status and dementia (OR, 2.64 [95% CI, 1.06-6.61]; FDR-corrected P = .08). Across 11 brain regions, significant associations were observed for semiquantitative p-tau burden in the frontal and parietal cortices, amygdala, and entorhinal cortex (OR range, 2.45-3.26). Among football players, the APOEε4 association size for CTE stage was similar to playing more than 7 years of football. Associations were significantly larger in the older half of the sample. There was no significant association for CTE status. Association sizes were similar when donors with an Alzheimer disease neuropathological diagnosis were excluded and were reduced but remained significant after adjusting for neuritic and diffuse amyloid plaques. No associations were observed for APOEε2 status. Models were adjusted for age at death and race. Conclusions and Relevance APOEε4 may confer increased risk for CTE-related neuropathological and clinical outcomes among older individuals with RHI exposure. Further work is required to validate these findings in an independent sample.
Collapse
Affiliation(s)
- Kathryn Atherton
- Boston University Bioinformatics Graduate Program, Boston, Massachusetts
| | - Xudong Han
- Boston University Bioinformatics Graduate Program, Boston, Massachusetts.,Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts
| | - Jaeyoon Chung
- Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, Massachusetts
| | - Jonathan D Cherry
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts.,VA Boston Healthcare System, Boston, Massachusetts.,Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, Massachusetts.,Department of Veterans Affairs Medical Center, Bedford, Massachusetts
| | - Zachary Baucom
- Boston University Department of Biostatistics, Boston University School of Public Health, Boston, Massachusetts
| | - Nicole Saltiel
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts.,VA Boston Healthcare System, Boston, Massachusetts.,Department of Veterans Affairs Medical Center, Bedford, Massachusetts
| | - Evan Nair
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts
| | - Bobak Abdolmohammadi
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts
| | - Madeline Uretsky
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts
| | | | - Conor Shea
- Boston University Bioinformatics Graduate Program, Boston, Massachusetts
| | - Shruti Durape
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts
| | - Brett M Martin
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts.,Biostatistics & Epidemiology Data Analytics Center, Boston University School of Public Health, Boston, Massachusetts
| | - Joseph N Palmisano
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts.,Biostatistics & Epidemiology Data Analytics Center, Boston University School of Public Health, Boston, Massachusetts
| | - Kurt Farrell
- Department of Pathology, Fishberg Department of Neuroscience, Friedman Brain Institute, Ronald M. Loeb Center for Alzheimer's Disease, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Christopher J Nowinski
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts.,Concussion Legacy Foundation, Boston, Massachusetts
| | - Victor E Alvarez
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts.,VA Boston Healthcare System, Boston, Massachusetts.,Department of Veterans Affairs Medical Center, Bedford, Massachusetts
| | - Brigid Dwyer
- Braintree Rehabilitation Hospital, Braintree, Massachusetts.,Department of Neurology, Boston University School of Medicine, Boston, Massachusetts
| | - Daniel H Daneshvar
- Department of Rehabilitation Medicine, Harvard Medical School, Boston, Massachusetts
| | - Douglas I Katz
- Braintree Rehabilitation Hospital, Braintree, Massachusetts.,Department of Neurology, Boston University School of Medicine, Boston, Massachusetts
| | - Lee E Goldstein
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts.,Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, Massachusetts.,Department of Neurology, Boston University School of Medicine, Boston, Massachusetts.,Department of Psychiatry, Boston University School of Medicine, Boston, Massachusetts
| | - Robert C Cantu
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts.,Department of Neurology, Boston University School of Medicine, Boston, Massachusetts.,Department of Neurosurgery, Emerson Hospital, Concord, Massachusetts
| | - Neil W Kowall
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts.,Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, Massachusetts.,Department of Neurology, Boston University School of Medicine, Boston, Massachusetts
| | - Michael L Alosco
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts.,Department of Neurology, Boston University School of Medicine, Boston, Massachusetts
| | - Bertrand R Huber
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts.,VA Boston Healthcare System, Boston, Massachusetts.,Department of Veterans Affairs Medical Center, Bedford, Massachusetts.,Department of Neurology, Boston University School of Medicine, Boston, Massachusetts
| | - Yorghos Tripodis
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts.,Boston University Department of Biostatistics, Boston University School of Public Health, Boston, Massachusetts
| | - John F Crary
- Department of Pathology, Fishberg Department of Neuroscience, Friedman Brain Institute, Ronald M. Loeb Center for Alzheimer's Disease, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Lindsay Farrer
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts.,Department of Medicine (Biomedical Genetics), Boston University School of Medicine, Boston, Massachusetts.,Boston University Department of Biostatistics, Boston University School of Public Health, Boston, Massachusetts.,Department of Neurology, Boston University School of Medicine, Boston, Massachusetts
| | - Robert A Stern
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts.,Department of Neurology, Boston University School of Medicine, Boston, Massachusetts
| | - Thor D Stein
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts.,VA Boston Healthcare System, Boston, Massachusetts.,Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, Massachusetts.,Department of Veterans Affairs Medical Center, Bedford, Massachusetts
| | - Ann C McKee
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts.,VA Boston Healthcare System, Boston, Massachusetts.,Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, Massachusetts.,Department of Veterans Affairs Medical Center, Bedford, Massachusetts.,Department of Neurology, Boston University School of Medicine, Boston, Massachusetts
| | - Jesse Mez
- Boston University Alzheimer's Disease and CTE Centers, Boston University School of Medicine, Boston, Massachusetts.,Department of Neurology, Boston University School of Medicine, Boston, Massachusetts
| |
Collapse
|
7
|
Diaz JR, Martá-Ariza M, Khodadadi-Jamayran A, Heguy A, Tsirigos A, Pankiewicz JE, Sullivan PM, Sadowski MJ. Apolipoprotein E4 Effects a Distinct Transcriptomic Profile and Dendritic Arbor Characteristics in Hippocampal Neurons Cultured in vitro. Front Aging Neurosci 2022; 14:845291. [PMID: 35572125 PMCID: PMC9099260 DOI: 10.3389/fnagi.2022.845291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 04/06/2022] [Indexed: 11/13/2022] Open
Abstract
The APOE gene is diversified by three alleles ε2, ε3, and ε4 encoding corresponding apolipoprotein (apo) E isoforms. Possession of the ε4 allele is signified by increased risks of age-related cognitive decline, Alzheimer's disease (AD), and the rate of AD dementia progression. ApoE is secreted by astrocytes as high-density lipoprotein-like particles and these are internalized by neurons upon binding to neuron-expressed apoE receptors. ApoE isoforms differentially engage neuronal plasticity through poorly understood mechanisms. We examined here the effects of native apoE lipoproteins produced by immortalized astrocytes homozygous for ε2, ε3, and ε4 alleles on the maturation and the transcriptomic profile of primary hippocampal neurons. Control neurons were grown in the presence of conditioned media from Apoe -/- astrocytes. ApoE2 and apoE3 significantly increase the dendritic arbor branching, the combined neurite length, and the total arbor surface of the hippocampal neurons, while apoE4 fails to produce similar effects and even significantly reduces the combined neurite length compared to the control. ApoE lipoproteins show no systemic effect on dendritic spine density, yet apoE2 and apoE3 increase the mature spines fraction, while apoE4 increases the immature spine fraction. This is associated with opposing effects of apoE2 or apoE3 and apoE4 on the expression of NR1 NMDA receptor subunit and PSD95. There are 1,062 genes differentially expressed across neurons cultured in the presence of apoE lipoproteins compared to the control. KEGG enrichment and gene ontology analyses show apoE2 and apoE3 commonly activate expression of genes involved in neurite branching, and synaptic signaling. In contrast, apoE4 cultured neurons show upregulation of genes related to the glycolipid metabolism, which are involved in dendritic spine turnover, and those which are usually silent in neurons and are related to cell cycle and DNA repair. In conclusion, our work reveals that lipoprotein particles comprised of various apoE isoforms differentially regulate various neuronal arbor characteristics through interaction with neuronal transcriptome. ApoE4 produces a functionally distinct transcriptomic profile, which is associated with attenuated neuronal development. Differential regulation of neuronal transcriptome by apoE isoforms is a newly identified biological mechanism, which has both implication in the development and aging of the CNS.
Collapse
Affiliation(s)
- Jenny R. Diaz
- Department of Neurology, New York University Grossman School of Medicine, New York, NY, United States
| | - Mitchell Martá-Ariza
- Department of Neurology, New York University Grossman School of Medicine, New York, NY, United States
| | | | - Adriana Heguy
- Department of Pathology, New York University Grossman School of Medicine, New York, NY, United States
| | - Aristotelis Tsirigos
- Department of Pathology, New York University Grossman School of Medicine, New York, NY, United States
| | - Joanna E. Pankiewicz
- Department of Neurology, New York University Grossman School of Medicine, New York, NY, United States
- Department of Biochemistry and Pharmacology, New York University Grossman School of Medicine, New York, NY, United States
| | - Patrick M. Sullivan
- Department of Medicine (Geriatrics), Duke University School of Medicine, Durham, NC, United States
- Durham VA Medical Center’s, Geriatric Research Education and Clinical Center, Durham, NC, United States
| | - Martin J. Sadowski
- Department of Neurology, New York University Grossman School of Medicine, New York, NY, United States
- Department of Biochemistry and Pharmacology, New York University Grossman School of Medicine, New York, NY, United States
- Department of Psychiatry, New York University Grossman School of Medicine, New York, NY, United States
| |
Collapse
|
8
|
Zhang H, Chiu PW, Ip I, Liu T, Wong GHY, Song YQ, Wong SWH, Herrup K, Mak HKF. Asymmetric left-right hippocampal glutamatergic modulation of cognitive control in ApoE-isoform subjects is unrelated to neuroinflammation. Eur J Neurosci 2021; 54:5310-5326. [PMID: 34309092 PMCID: PMC9290961 DOI: 10.1111/ejn.15399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 06/03/2021] [Accepted: 07/21/2021] [Indexed: 11/28/2022]
Abstract
The glutamatergic cycle is essential in modulating memory processing by the hippocampal circuitry. Our combined proton magnetic resonance spectroscopy (1H‐MRS) and task‐based functional magnetic resonance imaging (fMRI) study (using face‐name paired‐associates encoding and retrieval task) of a cognitively normal cohort of 67 healthy adults (18 ApoE4 carriers and 49 non‐ApoE4 carriers) found altered patterns of relationships between glutamatergic‐modulated synaptic signalling and neuronal activity or functional hyperaemia in the ApoE4 isoforms. Our study highlighted the asymmetric left–right hippocampal glutamatergic system in modulating neuronal activities in ApoE4 carriers versus non‐carriers. Such brain differentiation might be developmental cognitive advantages or compensatory due to impaired synaptic integrity and plasticity in ApoE4 carriers. As there was no difference in myoinositol levels measured by MRS between the ApoE4 and non‐ApoE4 subgroups, the mechanism is unlikely to be a response to neuroinflammation.
Collapse
Affiliation(s)
- Hui Zhang
- Department of Diagnostic Radiology, The University of Hong Kong, Hong Kong.,Alzheimer's Disease Research Network, The University of Hong Kong, Hong Kong
| | - Pui Wai Chiu
- Department of Diagnostic Radiology, The University of Hong Kong, Hong Kong.,State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong
| | - Isaac Ip
- Department of Educational Psychology, Chinese University of Hong Kong, Hong Kong
| | - Tianyin Liu
- Department of Social Work and Administration, The University of Hong Kong, Hong Kong
| | - Gloria Hoi Yan Wong
- Department of Social Work and Administration, The University of Hong Kong, Hong Kong
| | - You-Qiang Song
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong
| | - Savio Wai Ho Wong
- Department of Educational Psychology, Chinese University of Hong Kong, Hong Kong
| | - Karl Herrup
- Alzheimer Disease Research Centre, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Henry Ka Fung Mak
- Department of Diagnostic Radiology, The University of Hong Kong, Hong Kong.,Alzheimer's Disease Research Network, The University of Hong Kong, Hong Kong.,State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong
| |
Collapse
|
9
|
Pedroso RV, Fraga FJ, Pavarini SCI, Nascimento CMC, Ayán C, Cominetti MR. A Systematic Review of Altered P300 Event-Related Potential in Apolipoprotein E4 ( APOE4) Carriers. Clin EEG Neurosci 2021; 52:193-200. [PMID: 32945192 DOI: 10.1177/1550059420959966] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND Apolipoprotein ε4 allele (APOE4) is the strongest genetic risk factor for Alzheimer's disease and seems to be related to cognitive decline and damaged event-related potential P300, which is a sensitive measure to assess cognitive processing. OBJECTIVE This research aims to critically review the existing scientific evidence regarding the association between APOE4 and P300. METHODS A systematic review was carried out up to January 2020 on the following databases: Web of Science, Scopus and Medline/PubMed. Articles were considered for inclusion if they are original research that provided information regarding the association between APOE4 and P300, available in English, Spanish, or Portuguese, and available in full text. The methodological quality of the studies selected was evaluated using the quality assessment tool for observational cohort and cross-sectional studies recommended by Cochrane. RESULTS Out of 993 studies, 14 met the inclusion criteria. The results obtained showed that APOE4 is related to a longer P300 latency. However, the data supplied do not allow us to confirm if this relationship also occurs in amplitude measures. Moreover, it was observed that APOE genotype may influence P300 in different ages, from younger individuals to demented older people. CONCLUSION Evidence shows that APOE4 negatively influences cortical activities related to cognitive functions, as indicated by P300.
Collapse
Affiliation(s)
- Renata Valle Pedroso
- Department of Gerontology, 67828Federal University of São Carlos, São Carlos, SP, Brazil
| | - Francisco José Fraga
- Engineering, Modelling and Applied Social Sciences Center (CECS), 488580Federal University of the ABC (UFABC), Santo André, SP, Brazil
| | | | | | - Carlos Ayán
- Well-Move Research Group, Department of Special Didactics, 16784University of Vigo, Vigo, Spain.,IIS Galicia Sur, Vigo, Spain
| | | |
Collapse
|
10
|
Brás J, Gibbons E, Guerreiro R. Genetics of synucleins in neurodegenerative diseases. Acta Neuropathol 2021; 141:471-90. [PMID: 32740728 DOI: 10.1007/s00401-020-02202-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 07/23/2020] [Accepted: 07/24/2020] [Indexed: 12/14/2022]
Abstract
The SNCA locus currently has an indisputable role in Parkinson's disease and other synucleinopathies. The role of genetic variability in the other members of the synuclein family (SNCB and SNCG) in disease is far less clear. In this review, we critically assess the pathogenicity, main characteristics, and roles of genetic variants in these genes reported to be causative of synucleinopathies. We also summarize the different association signals identified in the SNCA locus that have been associated with risk for disease. We take a bird's eye view of the variability currently reported in the general population for the three genes and use these data to infer on the potential relationship between each of the genes and human disease.
Collapse
|
11
|
Coppens R, Rabinovich NE, Kanneganti R, Diggs HA, Wiggs K, Healey T, Huggenvik J, Rose GM, Gilbert DG. APOE genotype influences P3b amplitude and response to smoking abstinence in young adults. Psychopharmacology (Berl) 2021; 238:1171-1181. [PMID: 33506304 DOI: 10.1007/s00213-021-05763-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 01/12/2021] [Indexed: 11/27/2022]
Abstract
RATIONALE There is strong evidence that nicotine can enhance cognitive functions and growing evidence that this effect may be larger in young healthy APOE ε4 carriers. However, the moderating effects of the APOE ε4 allele on cognitive impairments caused by nicotine deprivation in chronic smokers have not yet been studied with brain indices. OBJECTIVE We sought to determine whether young female carriers of the APOE ε4 allele, relative to noncarriers, would exhibit larger abstinence-induced decreases in P3b amplitude during a two-stimulus auditory oddball task. METHODS We compared parietal P3bs in female chronic smokers with either APOE ε3/ε3 (n = 54) or ε3/ε4 (n = 20) genotype under nicotine-sated conditions and after 12-17-h nicotine deprivation. RESULTS Nicotine deprivation significantly reduced P3b amplitudes in APOE ε4 carriers, but not in APOE-ε3/ε3 individuals, such that the difference seen prior to nicotine deprivation was eliminated. CONCLUSIONS The results suggest that subjects with the APOE ε4 allele are more sensitive to nicotine, which could influence smoking patterns, the risk for nicotine dependence, and the cognitive effects of nicotine use in these individuals.
Collapse
Affiliation(s)
- Ryan Coppens
- Department of Psychology, Southern Illinois University, Carbondale, IL, USA
- Center for Integrated Research in Cognitive & Neural Sciences, Southern Illinois University, Carbondale, IL, USA
| | - Norka E Rabinovich
- Department of Psychology, Southern Illinois University, Carbondale, IL, USA
| | | | - Herman A Diggs
- Department of Psychology, Southern Illinois University, Carbondale, IL, USA
- Center for Integrated Research in Cognitive & Neural Sciences, Southern Illinois University, Carbondale, IL, USA
| | - Kristin Wiggs
- Department of Psychology, Southern Illinois University, Carbondale, IL, USA
| | - Travis Healey
- Department of Physiology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Jodi Huggenvik
- Department of Physiology, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - Gregory M Rose
- Center for Integrated Research in Cognitive & Neural Sciences, Southern Illinois University, Carbondale, IL, USA
- Department of Physiology, Southern Illinois University School of Medicine, Springfield, IL, USA
- Department of Anatomy, Southern Illinois University School of Medicine, Springfield, IL, USA
| | - David G Gilbert
- Department of Psychology, Southern Illinois University, Carbondale, IL, USA.
- Center for Integrated Research in Cognitive & Neural Sciences, Southern Illinois University, Carbondale, IL, USA.
- School of Psychological and Behavioral Sciences, Southern Illinois University, Mail Code 6502, Carbondale, IL, 62901, USA.
| |
Collapse
|
12
|
Gharbi-Meliani A, Dugravot A, Sabia S, Regy M, Fayosse A, Schnitzler A, Kivimäki M, Singh-Manoux A, Dumurgier J. The association of APOE ε4 with cognitive function over the adult life course and incidence of dementia: 20 years follow-up of the Whitehall II study. Alzheimers Res Ther 2021; 13:5. [PMID: 33397450 PMCID: PMC7784268 DOI: 10.1186/s13195-020-00740-0] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 12/07/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND Approximately 25% of the general population carries at least one ε4 allele of the Apolipoprotein E (APOE ε4), the strongest genetic risk factor for late onset Alzheimer's disease. Beyond its association with late-onset dementia, the association between APOE ε4 and change in cognition over the adult life course remains uncertain. This study aims to examine whether the association between Apolipoprotein E (APOE) ε4 zygosity and cognition function is modified between midlife and old age. METHODS A cohort study of 5561 participants (mean age 55.5 (SD = 5.9) years, 27.1% women) with APOE genotyping and repeated cognitive tests for reasoning, memory, and semantic and phonemic fluency, during a mean (SD) follow-up of 20.2 (2.8) years (the Whitehall II study). We used joint models to examine the association of APOE genotype with cognitive function trajectories between 45 and 85 years taking drop-out, dementia, and death into account and Fine and Gray models to examine associations with dementia. RESULTS Compared to non-carriers, heterozygote (prevalence 25%) and homozygote (prevalence 2%) APOE ε4 carriers had increased risk of dementia, sub-distribution hazard ratios 2.19 (95% CI 1.73, 2.77) and 5.97 (95% CI 3.85, 9.28) respectively. Using data spanning 45-85 years with non-ε4 carriers as the reference, ε4 homozygotes had poorer global cognitive score starting from 65 years; ε4 heterozygotes had better scores between 45 and 55 years, then no difference until poorer cognitive scores from 75 years onwards. In analysis of individual cognitive tests, better cognitive performance in the younger ε4 heterozygotes was primarily attributable to executive function. CONCLUSIONS Both heterozygous and homozygous ε4 carriers had poorer cognition and greater risk of dementia at older ages. Our findings show some support for a complex antagonist pleiotropic effect of APOE ε4 heterozygosity over the adult life course, characterized by cognitive advantage in midlife.
Collapse
Affiliation(s)
- Amin Gharbi-Meliani
- Université de Paris, Inserm U1153, Epidemiology of Ageing and Neurodegenerative Diseases, Paris, France
| | - Aline Dugravot
- Université de Paris, Inserm U1153, Epidemiology of Ageing and Neurodegenerative Diseases, Paris, France
| | - Séverine Sabia
- Université de Paris, Inserm U1153, Epidemiology of Ageing and Neurodegenerative Diseases, Paris, France
| | - Melina Regy
- Université de Paris, Inserm U1153, Epidemiology of Ageing and Neurodegenerative Diseases, Paris, France
| | - Aurore Fayosse
- Université de Paris, Inserm U1153, Epidemiology of Ageing and Neurodegenerative Diseases, Paris, France
| | - Alexis Schnitzler
- Université de Paris, Inserm U1153, Epidemiology of Ageing and Neurodegenerative Diseases, Paris, France
| | - Mika Kivimäki
- Department of Epidemiology and Public Health, University College London, London, UK
| | - Archana Singh-Manoux
- Université de Paris, Inserm U1153, Epidemiology of Ageing and Neurodegenerative Diseases, Paris, France.,Department of Epidemiology and Public Health, University College London, London, UK
| | - Julien Dumurgier
- Université de Paris, Inserm U1153, Epidemiology of Ageing and Neurodegenerative Diseases, Paris, France. .,Cognitive Neurology Center, Lariboisiere - Fernand Widal Hospital, AP-HP, Université de Paris, 200 rue du Faubourg Saint Denis, 75010, Paris, France.
| |
Collapse
|
13
|
Henson RN, Suri S, Knights E, Rowe JB, Kievit RA, Lyall DM, Chan D, Eising E, Fisher SE. Effect of apolipoprotein E polymorphism on cognition and brain in the Cambridge Centre for Ageing and Neuroscience cohort. Brain Neurosci Adv 2020; 4:2398212820961704. [PMID: 33088920 PMCID: PMC7545750 DOI: 10.1177/2398212820961704] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 08/27/2020] [Indexed: 01/01/2023] Open
Abstract
Polymorphisms in the apolipoprotein E (APOE) gene have been associated with individual differences in cognition, brain structure and brain function. For example, the ε4 allele has been associated with cognitive and brain impairment in old age and increased risk of dementia, while the ε2 allele has been claimed to be neuroprotective. According to the ‘antagonistic pleiotropy’ hypothesis, these polymorphisms have different effects across the lifespan, with ε4, for example, postulated to confer benefits on cognitive and brain functions earlier in life. In this stage 2 of the Registered Report – https://osf.io/bufc4, we report the results from the cognitive and brain measures in the Cambridge Centre for Ageing and Neuroscience cohort (www.cam-can.org). We investigated the antagonistic pleiotropy hypothesis by testing for allele-by-age interactions in approximately 600 people across the adult lifespan (18–88 years), on six outcome variables related to cognition, brain structure and brain function (namely, fluid intelligence, verbal memory, hippocampal grey-matter volume, mean diffusion within white matter and resting-state connectivity measured by both functional magnetic resonance imaging and magnetoencephalography). We found no evidence to support the antagonistic pleiotropy hypothesis. Indeed, Bayes factors supported the null hypothesis in all cases, except for the (linear) interaction between age and possession of the ε4 allele on fluid intelligence, for which the evidence for faster decline in older ages was ambiguous. Overall, these pre-registered analyses question the antagonistic pleiotropy of APOE polymorphisms, at least in healthy adults.
Collapse
Affiliation(s)
- Richard N Henson
- MRC Cognition & Brain Sciences Unit, University of Cambridge, Cambridge, UK.,Department of Psychiatry, University of Cambridge, Cambridge, UK
| | - Sana Suri
- Department of Psychiatry, Warneford Hospital, University of Oxford, Oxford, UK.,Wellcome Centre for Integrative Neuroimaging, University of Oxford, Oxford, UK
| | - Ethan Knights
- MRC Cognition & Brain Sciences Unit, University of Cambridge, Cambridge, UK
| | - James B Rowe
- MRC Cognition & Brain Sciences Unit, University of Cambridge, Cambridge, UK.,Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Rogier A Kievit
- MRC Cognition & Brain Sciences Unit, University of Cambridge, Cambridge, UK
| | - Donald M Lyall
- Institute of Health and Wellbeing, University of Glasgow, Glasgow, UK
| | - Dennis Chan
- Institute of Cognitive Neuroscience, University College London, London, UK
| | - Else Eising
- Language and Genetics Department, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
| | - Simon E Fisher
- Language and Genetics Department, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands.,Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
| |
Collapse
|
14
|
Smith CJ, Ashford JW, Perfetti TA. Putative Survival Advantages in Young Apolipoprotein ɛ4 Carriers are Associated with Increased Neural Stress. J Alzheimers Dis 2020; 68:885-923. [PMID: 30814349 PMCID: PMC6484250 DOI: 10.3233/jad-181089] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Inheritance of a single copy of the apolipoprotein E (APOE) ɛ4 allele increases risk of Alzheimer’s disease (AD) by 3-4-fold, with homozygosity associated with a 12-16-fold increase in risk, relative to ɛ3 allele homozygosity. There is a decreased risk associated with the APOE ɛ2 allele. The pathological consequence of APOE genotype has led to intense efforts to understand the mechanistic basis of the interplay between APOE status and loss of synapses. Numerous ɛ4 allele-related associations have been reported with the potential relevance of these associations to the pathogenesis of AD unknown at this time. In primarily young subjects, we have reviewed a representative body of literature on ɛ4 allele-associations related to the following: cardiovascular responses; impacts on reproduction and fetal development; co-morbidities; resistance to infectious disease; responses to head injury; biochemical differences possibly related to neural stress; and brain structure-function differences. In addition, the literature on the association between the ɛ4 allele and cognitive performance has been reviewed comprehensively. The weight-of-the-evidence supports the hypothesis that possession of the ancestral ɛ4 allele in youth is associated with improved fitness during fetal development, infancy, and youth relative to the more recently appearing ɛ3 allele, at the expense of decreased fitness in old age, which is substantially improved by the ɛ3 allele. However, possession of the ɛ4 allele is also associated with higher levels of synaptic macromolecular turnover, which likely stresses basic cellular neuroplasticity mechanisms. Clinical trials of potential AD therapeutics should consider APOE status as an enrollment criterion.
Collapse
Affiliation(s)
- Carr J Smith
- Florida State University, Department of Nurse Anesthesia, Panama City, FL, USA
| | - J Wesson Ashford
- Stanford University and VA Palo Alto Health Care System, Palo Alto, CA, USA
| | | |
Collapse
|
15
|
Har-Paz I, Roisman N, Michaelson DM, Moran A. Extra-Hippocampal Learning Deficits in Young Apolipoprotein E4 Mice and Their Synaptic Underpinning. J Alzheimers Dis 2019; 72:71-82. [PMID: 31561365 DOI: 10.3233/jad-190564] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The E4 allele of apolipoprotein (apoE4) is the primary genetic risk factor for late onset Alzheimer's disease (AD), yet the exact manner in which apoE4 leads to the development of AD is undetermined. Human and animal studies report that apoE4-related memory deficits appear earlier than the AD clinical manifestation, thus suggesting the existence of early, pre-pathological, apoE4 impairments that may later lead to AD onset. While current research regards the hippocampus as the initial and primary effected locus by apoE4, we presently investigate the possibility that apoE4 innately impairs any brain area that requires synaptic plasticity. To test this hypothesis, we trained young (3-4-month-old) target-replacement apoE3 and apoE4 mice in conditioned taste aversion (CTA) acquisition and extinction learnings- hippocampus-independent learnings that are easily performed at a young age. Synaptic vesicular markers analysis was conducted in the gustatory cortex (GC), basolateral amygdala (BLA), medial prefrontal cortex (mPFC), and hippocampal CA3 to reveal underlying apoE4-related impairments. We have found that young apoE4 mice are severely impaired in CTA acquisition and extinction learning. CTA acquisition impairments were correlated with reduced vGat and vGlut levels in the BLA and GC, but not in the CA3. CTA extinction was correlated with lower synaptophysin and vGlut levels in the mPFC, a central region in CTA extinction. Our results support apoE4-related early-life plasticity impairments that precede the AD clinical manifestations and affect any brain area that depends on extensive plasticity; early impairments that may promote the development of AD pathologies later in life.
Collapse
Affiliation(s)
- Ilona Har-Paz
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.,Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Nicole Roisman
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Daniel M Michaelson
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.,Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Anan Moran
- Department of Neurobiology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.,Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| |
Collapse
|
16
|
Li X, Hildebrandt A, Sommer W, Wilhelm O, Reuter M, Montag C, Zhou C. Cognitive Performance in Young APOE ε4 Carriers: A Latent Variable Approach for Assessing the Genotype-Phenotype Relationship. Behav Genet 2019; 49:455-68. [PMID: 31177340 DOI: 10.1007/s10519-019-09961-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 05/26/2019] [Indexed: 02/07/2023]
Abstract
The ε4 allele of the apolipoprotein (APOE) gene is a widely recognized genetic risk factor for developing Alzheimer's disease in older age. However, it is controversial whether there is a positive impact of the APOE ε4 allele on human cognitive performance in young adulthood, possibly representing a case of antagonistic pleiotropy. Here we explored associations of the APOE ε4 allele with cognitive ability in young adulthood. In contrast to previous studies, we used structural equation modeling that allows a multivariate measurement of the cognitive phenotype. Results based on four independent samples (N1 = 245; N2 = 300; N3 = 244; N4 = 206) overall revealed a complex effect of the APOE ε4 genotype on cognitive ability in young adulthood: Whereas the ε4 allele tends to be negatively associated with cognitive performance in individuals with lower education levels, there might be a weak positive association in persons with higher education-a finding that is partly in line with the antagonistic pleiotropy view on APOE and cognitive ability. The education-related findings support protective effects of environmental factors.
Collapse
|
17
|
Atkinson RÁ, Gaysina D, Rusted JM. Responses to executive demand in young adulthood differ by APOE genotype. Behav Brain Res 2019; 360:158-68. [PMID: 30472114 DOI: 10.1016/j.bbr.2018.11.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 11/06/2018] [Accepted: 11/21/2018] [Indexed: 11/23/2022]
Abstract
Despite evidence of a relationship between Apolipoprotein E (APOE) ε4+ and later-life cognitive decline, the lifespan effects of carrying an ε4+ allele on cognitive ageing are not well understood. Evidence of ε4+ advantages in early-life are inconsistent, but not inconsiderable. We explored the proposal that APOE ε4+ cognitive advantages arise only in response to complex and sensitive tasks targeting specific executive functions. We systematically manipulated executive demand within verbal fluency, decision-making, prospective memory, and sustained attention tasks. Participants aged 18-25 years (21 ε4+, 63 ε33) also completed a measure of subjective effort. Under low executive demand, ε4+ made fewer verbal fluency word repeats compared to ε33 carriers. Under high executive demand, ε4+ showed lower costs associated with performing concurrent tasks, greater switching errors, and more verbal fluency root repetition errors. Overall, ε4+ appeared to be showing working memory updating advantages under conditions of low executive demand, more effective resource allocation under elevated levels of executive demand, and errors indicating different strategy use compared to ε33 carriers, including speed-accuracy trade-offs.
Collapse
|
18
|
Bussy A, Snider BJ, Coble D, Xiong C, Fagan AM, Cruchaga C, Benzinger TLS, Gordon BA, Hassenstab J, Bateman RJ, Morris JC. Effect of apolipoprotein E4 on clinical, neuroimaging, and biomarker measures in noncarrier participants in the Dominantly Inherited Alzheimer Network. Neurobiol Aging 2018; 75:42-50. [PMID: 30530186 DOI: 10.1016/j.neurobiolaging.2018.10.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2018] [Revised: 09/28/2018] [Accepted: 10/05/2018] [Indexed: 11/19/2022]
Abstract
The apolipoprotein E ε4 allele (APOE4) is the major genetic risk factor for sporadic Alzheimer's disease (AD). APOE4 may have effects on cognition and brain atrophy years before the onset of symptomatic AD. We analyzed the effects of APOE4 in a unique cohort of young adults who had undergone comprehensive assessments as part of the Dominantly Inherited Alzheimer Network (DIAN), an international longitudinal study of individuals from families with autosomal dominant AD. We analyzed the effect of an APOE4 allele on cognitive measures, volumetric MRI, amyloid deposition, glucose metabolism, and on cerebrospinal fluid levels of AD biomarkers in 162 participants that did not carry the mutant gene (noncarriers). APOE4+ and APOE4- mutation noncarriers had similar performance on cognitive measures. Amyloid deposition began at an earlier age in APOE4+ participants, whereas hippocampal volume was similar between the groups. These preliminary findings are consistent with growing evidence that the APOE4 allele may exert effects in midlife years before symptom onset, promoting amyloid deposition before altering cognitive performance or brain structure.
Collapse
Affiliation(s)
- Aurélie Bussy
- Knight Alzheimer Disease Research Center, Washington University School of Medicine, Saint Louis, MO; Department of Neurology, Washington University School of Medicine, Saint Louis, MO
| | - B Joy Snider
- Knight Alzheimer Disease Research Center, Washington University School of Medicine, Saint Louis, MO; Department of Neurology, Washington University School of Medicine, Saint Louis, MO.
| | - Dean Coble
- Knight Alzheimer Disease Research Center, Washington University School of Medicine, Saint Louis, MO; Division of Biostatistics, Washington University School of Medicine, Saint Louis, MO
| | - Chengjie Xiong
- Knight Alzheimer Disease Research Center, Washington University School of Medicine, Saint Louis, MO; Division of Biostatistics, Washington University School of Medicine, Saint Louis, MO
| | - Anne M Fagan
- Knight Alzheimer Disease Research Center, Washington University School of Medicine, Saint Louis, MO; Department of Neurology, Washington University School of Medicine, Saint Louis, MO
| | - Carlos Cruchaga
- Knight Alzheimer Disease Research Center, Washington University School of Medicine, Saint Louis, MO; Department of Psychiatry, Washington University School of Medicine, Saint Louis, MO
| | - Tammie L S Benzinger
- Knight Alzheimer Disease Research Center, Washington University School of Medicine, Saint Louis, MO; Department of Radiology, Washington University School of Medicine, Saint Louis, MO
| | - Brian A Gordon
- Knight Alzheimer Disease Research Center, Washington University School of Medicine, Saint Louis, MO; Department of Radiology, Washington University School of Medicine, Saint Louis, MO
| | - Jason Hassenstab
- Knight Alzheimer Disease Research Center, Washington University School of Medicine, Saint Louis, MO; Department of Neurology, Washington University School of Medicine, Saint Louis, MO
| | - Randall J Bateman
- Knight Alzheimer Disease Research Center, Washington University School of Medicine, Saint Louis, MO; Department of Neurology, Washington University School of Medicine, Saint Louis, MO
| | - John C Morris
- Knight Alzheimer Disease Research Center, Washington University School of Medicine, Saint Louis, MO; Department of Neurology, Washington University School of Medicine, Saint Louis, MO
| |
Collapse
|
19
|
Abstract
Dietary and supplemental intake of the ω-3 fatty acid docosahexaenoic acid (DHA) reduces risk of Alzheimer’s disease (AD) and ameliorates symptoms. The apolipoprotein E (APOE)4 allele is the strongest risk factor for sporadic AD, exclusive of age. APOE4 carriers respond well to the DHA present in fish but do not respond as well to dietary supplements. The mechanisms behind this varied response remain unknown. I posit that the difference is that fish contain DHA in phospholipid form, whereas fish oil supplements do not. This influences whether DHA is metabolized to nonesterified DHA (free DHA) or a phospholipid form called lysophosphatidylcholine DHA (DHA-lysoPC). Free DHA is transported across the outer membrane leaflet of the blood–brain barrier (BBB) via passive diffusion, and DHA-lysoPC is transported across the inner membrane leaflet of the BBB via the major facilitator superfamily domain-containing protein 2A. I propose that APOE4 carriers have impaired brain transport of free DHA but not of DHA-lysoPC, as a consequence of a breakdown in the outer membrane leaflet of the BBB, putting them at increased risk for AD. Dietary sources of DHA in phospholipid form may provide a means to increase plasma levels of DHA-lysoPC, thereby decreasing the risk of AD.—Patrick, R. P. Role of phosphatidylcholine-DHA in preventing APOE4-associated Alzheimer’s disease.
Collapse
Affiliation(s)
- Rhonda P Patrick
- University of California San Francisco Benioff, Children's Hospital Oakland Research Institute, Oakland, California, USA
| |
Collapse
|
20
|
Rane S, Donahue MJ, Claassen DO. Amnestic mild cognitive impairment individuals with dissimilar pathologic origins show common regional vulnerability in the default mode network. Alzheimers Dement (Amst) 2018; 10:717-725. [PMID: 30511009 PMCID: PMC6258224 DOI: 10.1016/j.dadm.2018.08.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
INTRODUCTION Alzheimer's and Parkinson's disease (AD and PD) are distinct disorders but share similar biomarker profiles. The regions of the default mode network are implicated in these diseases and are associated with amnestic symptoms. The role of apolipoprotein-ε4 (APOE-ε4), which is associated with cognitive function, is unclear in PD. METHODS In this work, we evaluated cortical thickness of default mode network regions that are likely affected in both early AD and PD individuals, that is, with amnestic mild cognitive impairment. We identified the prevalence of APOE-ε4 and evaluated its association with cortical atrophy. RESULTS We observed significant parahippocampal atrophy and hippocampal atrophy rates in amnestic mild cognitive impairment subjects, regardless of disease origins (AD or PD). Similarly, mild cognitive impairment ε4 carriers showed significant precuneal atrophy compared with noncarriers. DISCUSSION This work supports that converging changes to default mode network regions, especially the temporal lobe and precuneus, are shared in AD and PD.
Collapse
Affiliation(s)
- Swati Rane
- Radiology, University of Washington Medical Center, Nashville, TN, USA
| | - Manus J. Donahue
- Neurology, Vanderbilt University Medical Center, Nashville, TN, USA
- Radiology, Vanderbilt University Medical Center, Nashville, TN, USA
- Psychiatry, Vanderbilt University Medical Center, Nashville, TN, USA
| | | |
Collapse
|
21
|
Weissberger GH, Nation DA, Nguyen CP, Bondi MW, Han SD. Meta-analysis of cognitive ability differences by apolipoprotein e genotype in young humans. Neurosci Biobehav Rev 2018; 94:49-58. [PMID: 30125600 DOI: 10.1016/j.neubiorev.2018.08.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 05/21/2018] [Accepted: 08/16/2018] [Indexed: 12/14/2022]
Abstract
The apolipoprotein (APOE) ε4 allele has been proposed as an example of an antagonistic pleiotropy gene, conferring a beneficial effect on cognition in early life and a detrimental impact on cognition during later years. However, findings on the cognitive associations of the ε4 allele in younger persons are mixed. This PRISMA conforming study aimed to investigate APOE genotype (e4/non-e4) associations across seven cognitive domains (intelligence/achievement, attention/working memory, executive functioning, memory, language, processing speed and visuospatial abilities) in younger humans using a meta-analytic approach. Of 689 records reviewed, 29 studies (34 data-points) were selected for the quantitative synthesis. Participants' ages ranged from 2-40. Results showed that young ε4 carriers did not statistically differ from non-ε4 carriers across any cognitive domains. Overall, findings do not provide compelling support for an antagonistic pleiotropic effect of the ε4 allele across the lifespan.
Collapse
Affiliation(s)
- Gali H Weissberger
- Department of Family Medicine, USC Keck School of Medicine, 1000 S. Fremont Avenue, Unit 22, HSA Building A-6, 4thFloor, Room 6437A, Alhambra, CA, 91803, USA.
| | - Daniel A Nation
- Department of Psychology, USC Dornsife College of Letters, Arts, and Sciences, Los Angeles, 90089, CA, USA
| | - Caroline P Nguyen
- Department of Family Medicine, USC Keck School of Medicine, 1000 S. Fremont Avenue, Unit 22, HSA Building A-6, 4thFloor, Room 6437A, Alhambra, CA, 91803, USA
| | - Mark W Bondi
- Department of Psychiatry, University of California, San Diego, 9500 Gilman Drive #9116-B, La Jolla, CA, 92093, USA
| | - S Duke Han
- Department of Family Medicine, USC Keck School of Medicine, 1000 S. Fremont Avenue, Unit 22, HSA Building A-6, 4thFloor, Room 6437A, Alhambra, CA, 91803, USA; Department of Psychology, USC Dornsife College of Letters, Arts, and Sciences, Los Angeles, 90089, CA, USA; USC School of Gerontology, Los Angeles, CA, 90089, USA; Department of Neurology, USC Keck School of Medicine, Los Angeles, 90033, CA, USA
| |
Collapse
|
22
|
Kunz L, Reuter M, Axmacher N, Montag C. Conscientiousness is Negatively Associated with Grey Matter Volume in Young APOE ɛ4-Carriers. J Alzheimers Dis 2018; 56:1135-1144. [PMID: 28106551 DOI: 10.3233/jad-160854] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The etiology of late onset Alzheimer's disease (LOAD) depends on multiple factors, among which the APOE ɛ4 allele is the most adverse genetic determinant and conscientiousness represents an influential personality trait. A potential association of both factors with brain structure in young adulthood may constitute a constellation that sets the course toward or against the subtle disease progression of LOAD that starts decades before clinical manifestation. Hence, in the present study, we examined the modulating effects of APOE ɛ4 on the relation between personality dimensions, including conscientiousness, and total grey matter volume (GMV) in young healthy adults using an a priori genotyping design. 105 participants completed an inventory assessing the Five Factor Model of Personality (NEO-FFI) and a structural MRI scan. Total GMV was estimated using both Freesurfer as well as VBM8. Across all participants, total GMV was positively associated with extraversion and negatively related to age. In APOE ɛ4-carriers- but not in APOE ɛ4-non-carriers- conscientiousness was negatively associated with total GMV. In line with the hypothesis of antagonistic pleiotropy of the APOE ɛ4 allele, this result suggests that young APOE ɛ4-carriers with increased total GMV may particularly benefit from cognitive advantages and thus have a lower need to engage in conscientious behavior. In this subset of young APOE ɛ4-carriers, the reduction in conscientiousness could then bring along adverse health behavior in the long run, potentiating the risk for LOAD. Hence, young APOE ɛ4-carriers with increased total GMV may be at a particularly high risk for LOAD.
Collapse
Affiliation(s)
- Lukas Kunz
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Department of Epileptology, University of Bonn, Bonn, Germany.,Department of Neuropsychology, Institute of Cognitive Neuroscience, Ruhr-University Bochum, Bochum, Germany
| | - Martin Reuter
- Department of Psychology, University of Bonn, Bonn, Germany.,Center for Economics and Neuroscience, University of Bonn, Bonn, Germany
| | - Nikolai Axmacher
- German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Department of Epileptology, University of Bonn, Bonn, Germany.,Department of Neuropsychology, Institute of Cognitive Neuroscience, Ruhr-University Bochum, Bochum, Germany
| | - Christian Montag
- Institute for Psychology and Education, Ulm University, Ulm, Germany.,Key Laboratory for NeuroInformation/Center for Information in BioMedicine, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| |
Collapse
|
23
|
Taylor WD, Boyd B, Turner R, McQuoid DR, Ashley-Koch A, MacFall JR, Saleh A, Potter GG. APOE ε4 associated with preserved executive function performance and maintenance of temporal and cingulate brain volumes in younger adults. Brain Imaging Behav 2018; 11:194-204. [PMID: 26843007 DOI: 10.1007/s11682-016-9522-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The APOE ε4 allele is associated with cognitive deficits and brain atrophy in older adults, but studies in younger adults are mixed. We examined APOE genotype effects on cognition and brain structure in younger adults and whether genotype effects differed by age and with presence of depression. 157 adults (32 % ε4 carriers, 46 % depressed) between 20 and 50 years of age completed neuropsychological testing, 131 of which also completed 3 T cranial MRI. We did not observe a direct effect of APOE genotype on cognitive performance or structural MRI measures. A significant genotype by age interaction was observed for executive function, where age had less of an effect on executive function in ε4 carriers. Similar interactions were observed for the entorhinal cortex, rostral and caudal anterior cingulate cortex and parahippocampal gyrus, where the effect of age on regional volumes was reduced in ε4 carriers. There were no significant interactions between APOE genotype and depression diagnosis. The ε4 allele benefits younger adults by allowing them to maintain executive function performance and volumes of cingulate and temporal cortex regions with aging, at least through age fifty years.
Collapse
Affiliation(s)
- Warren D Taylor
- The Geriatric Research, Education, and Clinical Center (GRECC), Department of Veterans Affairs Medical Center, Tennessee Valley Healthcare System, Nashville, TN, 37212, USA. .,The Center for Cognitive Medicine, Department of Psychiatry, Vanderbilt University Medical Center, 1601 23rd Avenue South, Nashville, TN, 37212, USA.
| | - Brian Boyd
- The Center for Cognitive Medicine, Department of Psychiatry, Vanderbilt University Medical Center, 1601 23rd Avenue South, Nashville, TN, 37212, USA
| | - Rachel Turner
- The Center for Cognitive Medicine, Department of Psychiatry, Vanderbilt University Medical Center, 1601 23rd Avenue South, Nashville, TN, 37212, USA
| | - Douglas R McQuoid
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, 27710, USA
| | - Allison Ashley-Koch
- Center for Human Disease Modeling and Department of Medicine, Duke University Medical Center, Durham, NC, 27710, USA
| | - James R MacFall
- Department of Radiology, Duke University Medical Center, Durham, NC, 27710, USA
| | - Ayman Saleh
- The Geriatric Research, Education, and Clinical Center (GRECC), Department of Veterans Affairs Medical Center, Tennessee Valley Healthcare System, Nashville, TN, 37212, USA
| | - Guy G Potter
- Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC, 27710, USA
| |
Collapse
|
24
|
Di Battista AM, Heinsinger NM, Rebeck GW. Alzheimer's Disease Genetic Risk Factor APOE-ε4 Also Affects Normal Brain Function. Curr Alzheimer Res 2017; 13:1200-1207. [PMID: 27033053 DOI: 10.2174/1567205013666160401115127] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 03/15/2016] [Accepted: 03/28/2016] [Indexed: 12/24/2022]
Abstract
APOE-ε4 is the strongest genetic risk factor for Alzheimer's disease (AD), and is associated with an increase in the levels of amyloid deposition and an early age of onset. Recent data demonstrate that AD pathological changes occur decades before clinical symptoms, raising questions about the precise onset of the disease. Now a convergence of approaches in mice and humans has demonstrated that APOE-ε4 affects normal brain function even very early in life in the absence of gross AD pathological changes. Normal mice expressing APOE4 have task-specific spatial learning deficits, as well as reduced NMDAR-dependent signaling and structural changes to presynaptic and postsynaptic compartments in neurons, particularly in hippocampal regions. Young humans possessing APOE-ε4 are more adept than APOE-ε4 negative individuals at some behavioral tasks, and functional magnetic resonance imaging has shown that inheritance of APOE-ε4 has specific effects on medial temporal brain activities. These findings suggest that inheritance of APOE-ε4 causes life long changes to the brain that may be related to the late risk of AD. Several possible mechanisms of how APOE-ε4 could affect brain neurochemistry, structure, and function are reviewed.
Collapse
Affiliation(s)
| | | | - G William Rebeck
- New Research Building, WP- 13, 3970 Reservoir Rd, NW, Washington, DC 20007; USA
| |
Collapse
|
25
|
Abstract
Apolipoprotein E (APOE) is a member of the vertebrate protein family of exchangeable apolipoproteins that is characterized by amphipathic α-helices encoded by multiple nucleotide tandem repeats. Its equivalent in flying insects - apolipophorin-III - shares structural and functional commonalities with APOE, suggesting the possibility of an evolutionary relationship between the proteins. In contrast to all other known species, human APOE is functionally polymorphic and possesses three major allelic variants (ε4, ε3 and ε2). The present review examines the current knowledge on APOE gene structure, phylogeny and APOE protein topology as well as its human isoforms. The ε4 allele is associated with an increased age-related disease risk but is also the ancestral form. Despite increased mortality in the elderly, ε4 has not become extinct and is the second-most common allele worldwide after ε3. APOE ε4, moreover, shows a non-random geographical distribution, and similarly, the ε2 allele is not homogenously distributed among ethnic populations. This likely suggests the existence of selective forces that are driving the evolution of human APOE isoforms, which may include differential interactions with dietary factors. To that effect, micronutrients such as vitamin D and carotenoids or dietary macronutrient composition are elucidated with respect to APOE evolution.
Collapse
Affiliation(s)
- Patricia Huebbe
- Institute of Human Nutrition and Food Science, University of Kiel, H. Rodewald Str. 6, 24118 Kiel, Germany.
| | - Gerald Rimbach
- Institute of Human Nutrition and Food Science, University of Kiel, H. Rodewald Str. 6, 24118 Kiel, Germany.
| |
Collapse
|
26
|
Mak E, Gabel S, Mirette H, Su L, Williams GB, Waldman A, Wells K, Ritchie K, Ritchie C, O’Brien J. Structural neuroimaging in preclinical dementia: From microstructural deficits and grey matter atrophy to macroscale connectomic changes. Ageing Res Rev 2017; 35:250-264. [PMID: 27777039 DOI: 10.1016/j.arr.2016.10.001] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 08/26/2016] [Accepted: 10/19/2016] [Indexed: 12/18/2022]
Abstract
The last decade has witnessed a proliferation of neuroimaging studies characterising brain changes associated with Alzheimer's disease (AD), where both widespread atrophy and 'signature' brain regions have been implicated. In parallel, a prolonged latency period has been established in AD, with abnormal cerebral changes beginning many years before symptom onset. This raises the possibility of early therapeutic intervention, even before symptoms, when treatments could have the greatest effect on disease-course modification. Two important prerequisites of this endeavour are (1) accurate characterisation or risk stratification and (2) monitoring of progression using neuroimaging outcomes as a surrogate biomarker in those without symptoms but who will develop AD, here referred to as preclinical AD. Structural neuroimaging modalities have been used to identify brain changes related to risk factors for AD, such as familial genetic mutations, risk genes (for example apolipoprotein epsilon-4 allele), and/or family history. In this review, we summarise structural imaging findings in preclinical AD. Overall, the literature suggests early vulnerability in characteristic regions, such as the medial temporal lobe structures and the precuneus, as well as white matter tracts in the fornix, cingulum and corpus callosum. We conclude that while structural markers are promising, more research and validation studies are needed before future secondary prevention trials can adopt structural imaging biomarkers as either stratification or surrogate biomarkers.
Collapse
|
27
|
Yassine HN, Croteau E, Rawat V, Hibbeln JR, Rapoport SI, Cunnane SC, Umhau JC. DHA brain uptake and APOE4 status: a PET study with [1- 11C]-DHA. Alzheimers Res Ther 2017; 9:23. [PMID: 28335828 PMCID: PMC5364667 DOI: 10.1186/s13195-017-0250-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 02/28/2017] [Indexed: 12/21/2022]
Abstract
BACKGROUND The apolipoprotein E ɛ4 (APOE4) allele is the strongest genetic risk factor identified for developing Alzheimer's disease (AD). Among brain lipids, alteration in the ω-3 polyunsaturated fatty acid docosahexaenoic acid (DHA) homeostasis is implicated in AD pathogenesis. APOE4 may influence both brain DHA metabolism and cognitive outcomes. METHODS Using positron emission tomography, regional incorporation coefficients (k*), rates of DHA incorporation from plasma into the brain using [1-11C]-DHA (J in), and regional cerebral blood flow using [15O]-water were measured in 22 middle-aged healthy adults (mean age 35 years, range 19-65 years). Data were partially volume error-corrected for brain atrophy. APOE4 phenotype was determined by protein expression, and unesterified DHA concentrations were quantified in plasma. An exploratory post hoc analysis of the effect of APOE4 on DHA brain kinetics was performed. RESULTS The mean global gray matter DHA incorporation coefficient, k*, was significantly higher (16%) among APOE4 carriers (n = 9) than among noncarriers (n = 13, p = 0.046). Higher DHA incorporation coefficients were observed in several brain regions, particularly in the entorhinal subregion, an area affected early in AD pathogenesis. Cerebral blood flow, unesterified plasma DHA, and whole brain DHA incorporation rate (J in) did not differ significantly between the APOE groups. CONCLUSIONS Our findings suggest an increase in the DHA incorporation coefficient in several brain regions in APOE4 carriers. These findings may contribute to understanding how APOE4 genotypes affect AD risk.
Collapse
Affiliation(s)
- Hussein N Yassine
- Department of Medicine, University of Southern California, 2250 Alcazar Street, Room 210, Los Angeles, CA, 90033, USA.
| | - Etienne Croteau
- Research Center on Aging, University of Sherbrooke, Sherbrooke, QC, Canada
| | - Varun Rawat
- Department of Medicine, University of Southern California, 2250 Alcazar Street, Room 210, Los Angeles, CA, 90033, USA
| | - Joseph R Hibbeln
- Section on Nutritional Neurosciences, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, MD, USA
| | - Stanley I Rapoport
- Brain Physiology and Metabolism Section, National Institute on Aging, National Institutes of Health, Bethesda, MD, USA
| | - Stephen C Cunnane
- Research Center on Aging, University of Sherbrooke, Sherbrooke, QC, Canada
| | - John C Umhau
- Section on Nutritional Neurosciences, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, MD, USA.,Division of Psychiatry Products, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, College Park, MD, USA
| |
Collapse
|
28
|
Abstract
OBJECTIVES The apolipoprotein E (APOE) ε4 allele is an established risk factor for dementia, yet this genetic variant is associated with a mixed cognitive profile across the lifespan. This study undertakes both a systematic and meta-analytic review of research investigating APOE-related differences in cognition in mid-adulthood, when detrimental effects of the allele may first be detectable. METHODS Thirty-six papers investigating the behavioral effects of APOE ε4 in mid-adulthood (defined as a mean sample age between 35 and 60 years) were reviewed. In addition, the effect of carrying an ε4 allele on individual cognitive domains was assessed in separate meta-analyses. RESULTS The average effect size of APOE ε4 status was non-significant across cognitive domains. Further consideration of genotype effects indicates preclinical effects of APOE ε4 may be observable in memory and executive functioning. CONCLUSIONS The cognitive profile of APOE ε4 carriers at mid-age remains elusive. Although there is support for comparable performance by ε4 and non-e4 carriers in the 5th decade, studies administering sensitive cognitive paradigms indicate a more nuanced profile of cognitive differences. Methodological issues in this field preclude strong conclusions, which future research must address, as well as considering the influence of further vulnerability factors on genotype effects. (JINS, 2016, 23, 239-253).
Collapse
|
29
|
Salas-Gomez D, Fernandez-Gorgojo M, Pozueta A, Diaz-Ceballos I, Lamarain M, Perez C, Sanchez-Juan P. Binge Drinking in Young University Students Is Associated with Alterations in Executive Functions Related to Their Starting Age. PLoS One 2016; 11:e0166834. [PMID: 27861563 PMCID: PMC5115818 DOI: 10.1371/journal.pone.0166834] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 11/06/2016] [Indexed: 11/26/2022] Open
Abstract
Our aim was to evaluate whether or not alcohol consumption in the form of binge drinking is associated with alterations of memory and executive functions in a population of university students. At the same time, we have studied the role of potential modulating factors, such as the APOE genotype or physical exercise.University students enrolled in academic year 2013–2014 at Escuelas Universitarias Gimbernat-Cantabria, affiliated with the University of Cantabria, were invited to participate in the study. We gathered sociodemographic data and details regarding the lifestyle of 206 students (mean age 19.55 ± 2.39; 67.5% women). We evaluated memory and executive functions via a series of validated cognitive tests. Participants were classified as binge drinkers (BD) and non-BD. Using Student's t-distribution we studied the association between cognitive tests and BD patterns. Multivariate analyses were carried out via multiple linear regression. 47.6% of the students were found to be BD. The BD differed significantly from the non-BD in their results in the executive functions test TMT B (43.41 ± 13.30 vs 37.40 ± 9.77; p = 0.0003). Adjusting by age, sex, academic records, age at which they started consuming alcohol, cannabis consumption, level of physical activity and other possible modifying variables, the association was statistically significant (p = 0.009). We noticed a statistically significant inverse correlation (Pearson’s r2 = -0.192; p = 0.007) between TMT B and starting age of alcohol consumption. Differences were observed in another executive functions test, TMT A, but only in the group of women (19.73±6.1 BD vs 17.78±5.4 non-BD p = 0.05). In spite of the young age of our participants, BD was associated with a lower performance in the executive functions test (TMT B). These deficits were related to the age at which they started drinking alcohol, suggesting an accumulative effect.
Collapse
Affiliation(s)
- Diana Salas-Gomez
- Gimbernat-Cantabria Research Unit (SUIGC), University Schools Gimbernat-Cantabria, Attached to the University of Cantabria, Torrelavega, Spain
- University Schools Gimbernat-Cantabria, Attached to the University of Cantabria, Torrelavega, Spain
| | - Mario Fernandez-Gorgojo
- Gimbernat-Cantabria Research Unit (SUIGC), University Schools Gimbernat-Cantabria, Attached to the University of Cantabria, Torrelavega, Spain
- University Schools Gimbernat-Cantabria, Attached to the University of Cantabria, Torrelavega, Spain
| | - Ana Pozueta
- University Schools Gimbernat-Cantabria, Attached to the University of Cantabria, Torrelavega, Spain
- Service of Neurology, University Hospital “Marqués de Valdecilla”, University of Cantabria (UC), CIBERNED, IDIVAL, Santander, Spain
| | - Isabel Diaz-Ceballos
- University Schools Gimbernat-Cantabria, Attached to the University of Cantabria, Torrelavega, Spain
| | - Maider Lamarain
- University Schools Gimbernat-Cantabria, Attached to the University of Cantabria, Torrelavega, Spain
| | - Carmen Perez
- Gimbernat-Cantabria Research Unit (SUIGC), University Schools Gimbernat-Cantabria, Attached to the University of Cantabria, Torrelavega, Spain
- University Schools Gimbernat-Cantabria, Attached to the University of Cantabria, Torrelavega, Spain
| | - Pascual Sanchez-Juan
- Gimbernat-Cantabria Research Unit (SUIGC), University Schools Gimbernat-Cantabria, Attached to the University of Cantabria, Torrelavega, Spain
- University Schools Gimbernat-Cantabria, Attached to the University of Cantabria, Torrelavega, Spain
- Service of Neurology, University Hospital “Marqués de Valdecilla”, University of Cantabria (UC), CIBERNED, IDIVAL, Santander, Spain
- * E-mail:
| |
Collapse
|
30
|
Konishi K, Bhat V, Banner H, Poirier J, Joober R, Bohbot VD. APOE2 Is Associated with Spatial Navigational Strategies and Increased Gray Matter in the Hippocampus. Front Hum Neurosci 2016; 10:349. [PMID: 27468260 PMCID: PMC4942687 DOI: 10.3389/fnhum.2016.00349] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 06/28/2016] [Indexed: 11/30/2022] Open
Abstract
The Apolipoprotein E (APOE) gene has a strong association with Alzheimer’s disease (AD). The ε4 allele is a well-documented genetic risk factor of AD. In contrast, the ε2 allele of the APOE gene is known to be protective against AD. Much of the focus on the APOE gene has been on the ε4 allele in both young and older adults and few studies have looked into the cognitive and brain structure correlates of the ε2 allele, especially in young adults. In the current study, we investigated the relationship between APOE genotype, navigation behavior, and hippocampal gray matter in healthy young adults. One-hundred and twenty-four healthy young adults were genotyped and tested on the 4on8 virtual maze, a task that allows for the assessment of navigation strategy. The task assesses the spontaneous use of either a hippocampus-dependent spatial strategy or a caudate nucleus-dependent response strategy. Of the 124 participants, 37 underwent structural magnetic resonance imaging (MRI). We found that ε2 carriers use a hippocampus-dependent spatial strategy to a greater extent than ε3 homozygous individuals and ε4 carriers. We also found that APOE ε2 allele carriers have more gray matter in the hippocampus compared to ε3 homozygous individuals and ε4 carriers. Our findings suggest that the protective effects of the ε2 allele may, in part, be expressed through increased hippocampus gray matter and increased use of hippocampus-dependent spatial strategies. The current article demonstrates the relationship between brain structure, navigation behavior, and APOE genotypes in healthy young adults.
Collapse
Affiliation(s)
- Kyoko Konishi
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University Verdun, QC, Canada
| | - Venkat Bhat
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University Verdun, QC, Canada
| | - Harrison Banner
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University Verdun, QC, Canada
| | - Judes Poirier
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University Verdun, QC, Canada
| | - Ridha Joober
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University Verdun, QC, Canada
| | - Véronique D Bohbot
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University Verdun, QC, Canada
| |
Collapse
|
31
|
Abstract
APOE ϵ4 - one of three possible allelic variants (ϵ2, ϵ3 and ϵ4) of the polymorphic protein APOE - is well characterized in its role as the strongest risk factor (after old age) for sporadic Alzheimer's disease (AD). Perhaps less well known, and certainly less well characterized, is that this ϵ4 variant of the APOE gene also is a significant risk factor for age-related cognitive decline in nonclinical populations. This article considers APOE ϵ4 effects on cognition in people without dementia, the extent to which such effects may depend on age and on gender and other interactive biological systems that change across the lifespan.
Collapse
|
32
|
Yasen AL, Raber J, Miller JK, Piper BJ. Sex, but not Apolipoprotein E Polymorphism, Differences in Spatial Performance in Young Adults. Arch Sex Behav 2015; 44:2219-26. [PMID: 25750133 PMCID: PMC4561598 DOI: 10.1007/s10508-015-0497-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 04/02/2014] [Accepted: 11/06/2014] [Indexed: 05/23/2023]
Abstract
The purpose of this study was to examine how sex and apolipoprotein E (APOE) genotype contribute to individual differences in spatial learning and memory. The associations of APOE genotype with neurocognitive function have been well studied among the elderly but less is known at earlier ages. Young adults (n = 169, 88 females) completed three neurocognitive tasks: mental rotation, spatial span, and Memory Island, a spatial navigation test. Males outperformed females on all three tasks: finding the hidden targets more quickly on Memory Island (Cohen's d = 0.62) and obtaining higher scores on mental rotation (d = 0.54) and spatial span (d = 0.37). In contrast, no significant effects of APOE were observed. The identified sex differences elaborate upon past literature documenting sexually dimorphic performance on specific neurobehavioral tasks.
Collapse
Affiliation(s)
- Alia L Yasen
- Department of Psychology, Willamette University, Salem, OR, USA
| | - Jacob Raber
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, USA
- Division of Neuroscience and Department of Neurology, Oregon Health and Science University, Portland, OR, USA
| | - Jeremy K Miller
- Department of Psychology, Willamette University, Salem, OR, USA
| | - Brian J Piper
- Department of Psychology, Willamette University, Salem, OR, USA.
- Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, USA.
- Department of Basic Pharmaceutical Sciences, Husson University, Bangor, ME, 04401, USA.
| |
Collapse
|
33
|
Greenwood PM, Espeseth T, Lin MK, Reinvang I, Parasuraman R. Longitudinal change in working memory as a function of APOE genotype in midlife and old age. Scand J Psychol 2015; 55:268-77. [PMID: 24853824 DOI: 10.1111/sjop.12123] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 02/17/2014] [Indexed: 01/17/2023]
Abstract
Previous investigations into whether the APOE-ε4 allele exerts cognitive effects at midlife have been inconclusive. We have advanced a "cognitive phenotype" hypothesis arguing that the ε4 allele of the apolipoprotein E gene (APOE) is associated with lower efficiency of neuronal plasticity thereby resulting in poorer cognitive performance independently of the pathology of Alzheimer's disease (Greenwood et al., ). This hypothesis is best tested at midlife, prior to the neuron loss associated with AD diagnosis. This hypothesis predicts that the ε4 allele would alter cognition regardless of age through plasticity mechanisms, but would not induce longitudinal decline in midlife. The alternative "prodrome" hypothesis predicts that the APOE-ε4 allele would be associated with longitudinal cognitive decline as early as midlife due to prodromal effects of AD. We tested these hypotheses with a working memory task in a large cross-sectional sample of cognitively screened APOE-ε4 carriers and non-carriers and also in a small longitudinal sample over 3 years. The sample was divided into middle-aged (mean age 50, range 40-59) and older (mean age 69, range 60-84) individuals. Cross-sectionally, we observed that older, but not middle-aged, APOE-ε4 carriers had lower accuracy than ε4 non-carriers, mainly under the hardest discrimination condition. Longitudinally, we observed increases in accuracy in middle-aged APOE-ε4 carriers, suggesting a cognitive phenotype that includes ability to benefit from experience. We observed a longitudinal decrease in older APOE-ε4 carriers, suggesting an AD prodrome.
Collapse
|
34
|
Koleck TA, Bender CM, Sereika SM, Ahrendt G, Jankowitz RC, McGuire KP, Ryan CM, Conley YP. Apolipoprotein E genotype and cognitive function in postmenopausal women with early-stage breast cancer. Oncol Nurs Forum 2015; 41:E313-25. [PMID: 25355028 DOI: 10.1188/14.onf.e313-e325] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
PURPOSE/OBJECTIVES To examine the role of apolipoprotein E (APOE) genotype in the cognitive function of postmenopausal women with early-stage breast cancer prior to initiation of adjuvant therapy and over time with treatment. DESIGN Longitudinal, genetic association study. SETTING Urban university cancer center. SAMPLE Three cohorts of postmenopausal women: 37 women with breast cancer receiving chemotherapy and anastrozole, 41 women with breast cancer receiving anastrozole alone, and 50 healthy women. METHODS Cognitive function was evaluated three times during a 12-month period using a comprehensive neuropsychological test battery. Participants were genotyped and classified based on the presence or absence of at least one APOE e4 allele. Multiple linear regression was used to determine if APOE genotype accounted for observed variability in cognitive function data. MAIN RESEARCH VARIABLES APOE genotype, breast cancer treatment, and cognitive function. FINDINGS Performance or changes in performance on tasks of executive function, attention, verbal learning and memory, and visual learning and memory were found to be influenced by APOE genotype and/or interactions between APOE genotype and study cohort. CONCLUSIONS The results indicate that cognitive function in postmenopausal women with breast cancer is modified by APOE genotype and the combination of APOE genotype and treatment. IMPLICATIONS FOR NURSING APOE genotype, along with other biomarkers, may be used in the future to assist nurses in identifying women with breast cancer most at risk for cognitive decline.
Collapse
Affiliation(s)
| | | | - Susan M Sereika
- Department of Biostatistics, Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh in Pennsylvania
| | - Gretchen Ahrendt
- Department of Surgery, Division of Surgical Oncology, in the School of Medicine, University of Pittsburgh in Pennsylvania
| | - Rachel C Jankowitz
- Department of Medicine in the School of Medicine, University of Pittsburgh in Pennsylvania
| | - Kandace P McGuire
- Department of Surgery in the School of Medicine, University of Pittsburgh in Pennsylvania
| | - Christopher M Ryan
- School of Nursing and in the Department of Psychiatry in the School of Medicine, University of Pittsburgh in Pennsylvania
| | - Yvette P Conley
- Department of Human Genetics in the Graduate School of Public Health, University of Pittsburgh in Pennsylvania
| |
Collapse
|
35
|
Burnand G. The backup is active in Alzheimer's disease: a hypothesis from problem theory. Med Hypotheses 2015; 84:241-8. [PMID: 25632793 DOI: 10.1016/j.mehy.2015.01.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 12/23/2014] [Accepted: 01/06/2015] [Indexed: 10/24/2022]
Abstract
Problem theory distinguishes between six general problems of everyday life, which people work through in turn during childhood, learning to switch between them. One of them requires the protection of a cut-out and an override. People who develop Alzheimer's disease (AD), and apolipoprotein allele epsilon 4 carriers, are preoccupied with this problem, or readily switch back to it. It is the freedom problem, of raising hope or confidence of freedom or power to control. Here people try to raise hope of success with any task on which attention happens to rest. This indiscriminateness means that there is no basis for giving up on a task, or for avoiding dangerous environments. Thus the cut-out is needed when someone becomes stuck on a mental task and the override is needed so as to help in avoiding danger. Activity relevant to the freedom problem is confined to the left hemisphere and the right hemisphere operates the cut-out and override. In providing these two forms of protection the right hemisphere can be said to act as a backup. Accordingly EEG, metabolism, and atrophy findings indicate that both cut-out and override are active in mild clinical impairment, especially among patients who later develop AD. The pattern of atrophy of AD matches what would be expected from disuse caused by an overactive cut-out followed by an overactive override. A parallel loss of testosterone might contribute to the weakening of resistance to infections leading to autoimmune effects.
Collapse
|
36
|
Yong SM, Lim ML, Low CM, Wong BS. Reduced neuronal signaling in the ageing apolipoprotein-E4 targeted replacement female mice. Sci Rep 2014; 4:6580. [PMID: 25301084 PMCID: PMC4192620 DOI: 10.1038/srep06580] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 09/16/2014] [Indexed: 12/22/2022] Open
Abstract
The effect of ApoE on NMDAR-dependent ERK/CREB signaling is isoform-dependent, and ApoE4 accelerates memory decline in ageing. However, this isoform-dependent function on neuronal signaling during ageing is unclear. In this study, we have examined NMDAR-associated ERK/CREB signal transduction in young and aged huApoE3 and huApoE4 targeted replacement (TR) mice. At 12 weeks huApoE4 mouse brain, increased NR1-S896 phosphorylation was linked to higher protein kinase C (PKC) activation. This up-regulation was accompanied by higher phosphorylation of AMPA GluR1-S831, CaMKII, ERK1/2 and CREB. But at 32 weeks, there was no significant difference between huApoE3 and huApoE4 TR mice on NMDAR-associated ERK/CREB signaling. Interestingly, in 72-week-old huApoE4 TR mice, protein phosphorylation that were increased in younger mice were significantly reduced. Lower NR1-S896 phosphorylation was linked to reduced PKC, GluR1-S831, CaMKII, ERK1/2 and CREB phosphorylation in huApoE4 TR mice as compared to huApoE3 TR mice. Furthermore, we have consistently detected lower ApoE levels in young and aged huApoE4 TR mouse brain, and this was associated with reduced expression of the ApoE receptor, LRP1 and NR2A-Y1246 phosphorylation. These results suggest age-specific, isoform-dependent effects of ApoE on neuronal signaling.
Collapse
Affiliation(s)
- Shan-May Yong
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Mei-Li Lim
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Chian-Ming Low
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Boon-Seng Wong
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| |
Collapse
|
37
|
Nwabuisi-Heath E, Rebeck GW, Ladu MJ, Yu C. ApoE4 delays dendritic spine formation during neuron development and accelerates loss of mature spines in vitro. ASN Neuro 2014; 6:e00134. [PMID: 24328732 DOI: 10.1042/AN20130043] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The ε4 allele of the gene that encodes apolipoprotein E (APOE4) is the greatest genetic risk factor for Alzheimer's disease (AD), while APOE2 reduces AD risk, compared to APOE3. The mechanism(s) underlying the effects of APOE on AD pathology remains unclear. In vivo, dendritic spine density is lower in APOE4-targeted replacement (APOE-TR) mice compared with APOE2- and APOE3-TR mice. To investigate whether this apoE4-induced decrease in spine density results from alterations in the formation or the loss of dendritic spines, the effects of neuron age and apoE isoform on the total number and subclasses of spines were examined in long-term wild-type neurons co-cultured with glia from APOE2-, APOE3- and APOE4-TR mice. Dendritic spine density and maturation were evaluated by immunocytochemistry via the presence of drebrin (an actin-binding protein) with GluN1 (NMDA receptor subunit) and GluA2 (AMPA receptor subunit) clusters. ApoE isoform effects were analyzed via a method previously established that identifies phases of spine formation (day-in-vitro, DIV10–18), maintenance (DIV18–21) and loss (DIV21–26). In the formation phase, apoE4 delayed total spine formation. During the maintenance phase, the density of GluN1+GluA2 spines did not change with apoE2, while the density of these spines decreased with apoE4 compared to apoE3, primarily due to the loss of GluA2 in spines. During the loss phase, total spine density was lower in neurons with apoE4 compared to apoE3. Thus, apoE4 delays total spine formation and may induce early synaptic dysfunction via impaired regulation of GluA2 in spines.
Collapse
|
38
|
Suri S, Heise V, Trachtenberg AJ, Mackay CE. The forgotten APOE allele: a review of the evidence and suggested mechanisms for the protective effect of APOE ɛ2. Neurosci Biobehav Rev 2013; 37:2878-86. [PMID: 24183852 DOI: 10.1016/j.neubiorev.2013.10.010] [Citation(s) in RCA: 142] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Revised: 09/22/2013] [Accepted: 10/21/2013] [Indexed: 01/05/2023]
Abstract
Ongoing efforts to improve survival, and enhance quality of life have led biomedical research to focus on disease and the mechanisms that increase risk for disease. The other side of that coin may be as important, i.e. examining the protective factors that allow some individuals to enjoy long, healthy lives. One of the best examples of a gene that positively influences cognitive health is the apolipoprotein (APOE) ɛ2 allele. The APOE ɛ4 allele is a well-established risk factor for Alzheimer's disease (AD) and has thus dominated the APOE literature, with the putative protective role of ɛ2 receiving little attention. This review describes the effects of APOE ɛ2 on the structure and function of the brain. With a focus on neurodegeneration, we discuss evidence for APOE ɛ2's protective effects, explore some key mechanisms through which this protection may be conferred, and address a few inconsistencies in the literature. Understanding the mechanisms that underlie the association between APOE ɛ2, cognition and longevity may provide new targets for research on promoting life-long health.
Collapse
Affiliation(s)
- Sana Suri
- Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford OX3 7JX, United Kingdom; FMRIB Centre (Oxford Centre for Functional Magnetic Resonance Imaging of the Brain), University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, United Kingdom.
| | | | | | | |
Collapse
|
39
|
Shin MH, Kweon SS, Choi JS, Lee YH, Nam HS, Park KS, Kim HN, Song HR, Kim BC, Choi SM, Oh SY, Jeong SK. The effect of an APOE polymorphism on cognitive function depends on age. J Neurol 2014; 261:66-72. [PMID: 24146255 DOI: 10.1007/s00415-013-7157-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 10/11/2013] [Accepted: 10/11/2013] [Indexed: 10/26/2022]
Abstract
It remains controversial whether APOE E4 polymorphism is related to cognitive function in general population. We aimed to evaluate an association between the APOE E4 genotype and cognitive function, and whether this association may differ by age. Cognitive function was assessed using the Korean version of modified Mini-Mental State Examination (K-mMMSE) in 10,371 Koreans aged 45-74 years in Namwon City. According to the APOE E4 status, all participants were classified as non-carriers, heterozygotes, or homozygotes. Multiple linear and logistic regression models were used to evaluate the association between APOE genotypes and cognition. The frequency of APOE genotypes in the study population was 0.4, 10.1, 1.1, 72.9, 14.7 and 0.8 % for E2E2, E2E3, E2E4, E3E3, E3E4, and E4E4, respectively. Compared to the APOE E4 non-carriers, the heterozygotes and homozygotes showed 1.3 and 7.3 % lower K-mMMSE scores at 65-74 years and 0.8 and 4.6 % higher scores at 45-55 years, respectively. Educational attainment modified the effect of APOE E4 on cognitive function in the 45-54 age group (p for interaction =0.003), showing that the E4 carriers with no-formal education showed significantly higher cognitive function than those with formal education. The present study demonstrates that the effect of APOE E4 on cognitive function depends on age and education.
Collapse
|
40
|
Wierenga CE, Clark LR, Dev SI, Shin DD, Jurick SM, Rissman RA, Liu TT, Bondi MW. Interaction of age and APOE genotype on cerebral blood flow at rest. J Alzheimers Dis 2013; 34:921-35. [PMID: 23302659 DOI: 10.3233/jad-121897] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
We investigated the impact of APOE genotype on cerebral blood flow (CBF) in older and younger adults. Forty cognitively normal older adults (16 ε4 carriers, 24 non-ε4 carriers) and 30 younger adults (15 ε4 carriers, 15 non-ε4 carriers) completed a resting-state whole-brain pulsed arterial spin labeling magnetic resonance scan. Main effects of aging were demonstrated wherein older adults had decreased gray matter CBF corrected for partial volume effects compared to younger adults in widespread brain regions. Main effects of APOE genotype were also observed wherein ε4 carriers displayed greater CBF in the left lingual gyrus and precuneus than non-carriers. An interaction between age and APOE genotype in the left anterior cingulate cortex (ACC) was characterized by reduced CBF in older ε4 carriers and increased CBF in young ε4 carriers. Increased CBF in the left ACC resulting from the interaction of age group and APOE genotype was positively correlated with executive functioning in young ε4 adults (r = 0.61, p = 0.04). Results demonstrate APOE genotype differentially impacts cerebrovascular function across the lifespan and may modify the relationship between CBF and cognition. Findings may partially support suggestions that the gene exerts antagonistic pleiotropic effects.
Collapse
Affiliation(s)
- Christina E Wierenga
- Research Service, Veterans Affairs San Diego Healthcare System, San Diego, CA, USA.
| | | | | | | | | | | | | | | |
Collapse
|
41
|
Bunce D, Bielak AAM, Anstey KJ, Cherbuin N, Batterham PJ, Easteal S. APOE genotype and cognitive change in young, middle-aged, and older adults living in the community. J Gerontol A Biol Sci Med Sci 2013; 69:379-86. [PMID: 23902936 DOI: 10.1093/gerona/glt103] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We examined whether the apolipoprotein E (APOE) ε4 allele was associated with cognitive benefits in young adulthood and whether it reversed to confer cognitive deficits in later life ("antagonistic pleiotropy") in the absence of dementia-related neuropathology. We also tested whether the ε2 allele was associated with disadvantages in early adulthood but offered protection against cognitive decline in early old age. Eight-year cognitive change was assessed in 2,013 cognitively normal community-dwelling adults aged 20-24, 40-44, or 60-64 years at baseline. Although cognitive decline was associated with age, multilevel models contrasting the ε2 and ε4 alleles provided no evidence that the APOE genotype was related to cognitive change in any of the age groups. The findings suggest that in the absence of clinically salient dementia pathology, APOE ε2 and ε4 alleles do not exhibit antagonistic pleiotropy in relation to cognition between the ages of 20 and 72 years.
Collapse
Affiliation(s)
- David Bunce
- Institute of Psychological Science, Faculty of Medicine and Health, University of Leeds, Leeds, LS2 9JT UK.
| | | | | | | | | | | |
Collapse
|
42
|
Panos SE, Hinkin CH, Singer EJ, Thames AD, Patel SM, Sinsheimer JS, Del Re AC, Gelman BB, Morgello S, Moore DJ, Levine AJ. Apolipoprotein-E genotype and human immunodeficiency virus-associated neurocognitive disorder: the modulating effects of older age and disease severity. ACTA ACUST UNITED AC 2013; 5:11-22. [PMID: 26617462 DOI: 10.2147/nbhiv.s39573] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND The apolipoprotein-E (APOE) ε4 allele is a risk factor for vascular dementia and Alzheimer's disease. Recent studies are equivocal with regards to whether or not the ε4 allele confers increased risk for the development of human immunodeficiency virus (HIV)-associated neurocognitive disorder (HAND), but suggest that age and/or disease severity may be modulating factors. The aim of this study was to assess the interactions and contributions of APOE genotype, age, and HIV disease severity as risk factors for HAND in HIV-infected adults. METHODS Participants were 259 HIV-positive individuals who underwent APOE genotyping, a standardized neurological evaluation, a comprehensive neuropsychological evaluation, and laboratory testing. RESULTS Older ε4 carriers showed a higher frequency of HAND compared with age-matched non-ε4 carriers. Analysis by discrete neurocognitive domain revealed that advanced age modulated the effect of the ε4 allele, such that older ε4 allele carriers showed reduced executive functioning and information processing speed. Exploratory analyses assessing the relationship between ε4 and disease severity in the overall sample revealed that disease severity modulated the effect of the ε4 allele on cognition. Lower absolute CD4+ cell count among ε4 allele carriers was associated with poorer working memory ability. CONCLUSION Advancing age and degree of immunosuppression may influence the association between APOE ε4 allele status and HAND. These two factors need to be taken into account in future research.
Collapse
Affiliation(s)
- Stella E Panos
- Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, David Geffen School of Medicine ; VA Greater Los Angeles Healthcare System
| | - Charles H Hinkin
- Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, David Geffen School of Medicine ; VA Greater Los Angeles Healthcare System
| | - Elyse J Singer
- National Neurological AIDS Bank, UCLA Department of Neurology
| | - April D Thames
- Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, David Geffen School of Medicine ; VA Greater Los Angeles Healthcare System
| | - Sapna M Patel
- Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, David Geffen School of Medicine ; VA Greater Los Angeles Healthcare System
| | - Janet S Sinsheimer
- Departments of Biomathematics and Human Genetics, University of California Los Angeles, David Geffen School of Medicine, Los Angeles, CA
| | - A C Del Re
- Department of Psychiatry, Stanford University, Menlo Park, CA
| | - Benjamin B Gelman
- Department of Pathology, University of Texas Medical Branch, Galveston, TX
| | - Susan Morgello
- Departments of Neurology, Neuroscience, and Pathology, The Mount Sinai School of Medicine, New York, NY
| | - David J Moore
- Department of Psychiatry, School of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Andrew J Levine
- National Neurological AIDS Bank, UCLA Department of Neurology
| |
Collapse
|
43
|
Evans S, Gray MA, Dowell NG, Tabet N, Tofts PS, King SL, Rusted JM. APOE E4 Carriers show prospective memory enhancement under nicotine, and evidence for specialisation within medial BA10. Neuropsychopharmacology 2013; 38:655-63. [PMID: 23232444 DOI: 10.1038/npp.2012.230] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
There is evidence to suggest that the APOE ɛ4 allele (which confers an increased risk of developing dementia) might be associated with cognitive advantages earlier in life. Further, nicotine might selectively benefit ɛ4 carriers. We used fMRI to explore performance on a prospective memory (PM) task in young adults (age 18-30) with and without nicotine using a within-subjects design. Participants performed an ongoing task while retaining a PM instruction to respond to specific stimuli embedded in the task. Nicotine effects varied according to APOE status. Reaction times to the PM cue were improved under nicotine in ɛ4 carriers, but not in ɛ3 carriers. In an event-related analysis, extrastriate responses to PM trials were enhanced by nicotine only in ɛ4 carriers. These differences in early visual processing may contribute to the behavioral findings. Activity in medial BA10 (previously implicated in PM) differentiated ɛ4 from ɛ3 carriers. One BA10 subregion showed greater deactivation in ɛ4 carriers during PM trials. Activity in other BA10 subregions was modulated by PM reaction time, pointing to region-specific effects within medial BA10. In addition, activity in right hippocampal formation was only seen in ɛ4 carriers receiving nicotine. These results demonstrate that cognitive enhancement by nicotine can selectively benefit APOE ɛ4 carriers, and point to genotype-specific differences in neural activity during PM. In addition, these results show that the role of medial BA10 in PM likely involves varying contributions from functionally specific subregions.
Collapse
|
44
|
Moreau PH, Bott JB, Zerbinatti C, Renger JJ, Kelche C, Cassel JC, Mathis C. ApoE4 confers better spatial memory than apoE3 in young adult hAPP-Yac/apoE-TR mice. Behav Brain Res 2013; 243:1-5. [PMID: 23291160 DOI: 10.1016/j.bbr.2012.12.043] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Revised: 12/21/2012] [Accepted: 12/24/2012] [Indexed: 12/17/2022]
Abstract
The APOE-ɛ4 allele is associated with increased cognitive decline during normal aging and Alzheimer's disease. However, several studies intriguingly found a beneficial effect on cognition in young adult human APOE-ɛ4 carriers. Here, we show that 3-month old bigenic hAPP-Yac/apoE4-TR mice outperformed their hAPP-Yac/apoE3-TR counterparts on learning and memory performances in the highly hippocampus-dependent, hidden-platform version of the Morris water maze task. The two mouse lines did not differ in a non-spatial visible-platform version of the task. This hAPP-Yac/apoE-TR model may thus provide a useful tool to study the mechanisms involved in the antagonistic pleiotropic effects of APOE-ɛ4 on cognitive functions.
Collapse
Affiliation(s)
- Pierre-Henri Moreau
- Laboratoire d'Imagerie et de Neurosciences Cognitives, UMR 7237 CNRS, Université de Strasbourg, IFR 37, GDR CNRS 2905, 12 rue Goethe, F-67000 Strasbourg, France
| | | | | | | | | | | | | |
Collapse
|
45
|
Rusted JM, Evans SL, King SL, Dowell N, Tabet N, Tofts PS. APOE e4 polymorphism in young adults is associated with improved attention and indexed by distinct neural signatures. Neuroimage 2012; 65:364-73. [PMID: 23063453 DOI: 10.1016/j.neuroimage.2012.10.010] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Revised: 09/27/2012] [Accepted: 10/05/2012] [Indexed: 10/27/2022] Open
Abstract
The APOE e4 allele, which confers an increased risk of developing dementia in older adulthood, has been associated with enhanced cognitive performance in younger adults. An objective of the current study was to compare task-related behavioural and neural signatures for e4 carriers (e4+) and non-e4 carriers (e4-) to help elucidate potential mechanisms behind such cognitive differences. On two measures of attention, we recorded clear behavioural advantages in young adult e4+ relative to e4-, suggesting that e4+ performed these tasks with a wider field of attention. Behavioural advantages were associated with increased task-related brain activations detected by fMRI (BOLD). In addition, behavioural measures correlated with structural measures derived from a former DTI analysis of white matter integrity in our cohort. These data provide clear support for an antagonistic pleiotropy hypothesis--that the e4 allele confers some cognitive advantage in early life despite adverse consequences in old age. The data implicate differences in both structural and functional signatures as complementary mediators of the behavioural advantage.
Collapse
Affiliation(s)
- J M Rusted
- School of Psychology, University of Sussex, Brighton BN1 9QG, UK.
| | | | | | | | | | | |
Collapse
|
46
|
Affiliation(s)
- I. W. Hamley
- Department
of Chemistry, University of Reading, Whiteknights, Reading RG6 6AD,
U.K
| |
Collapse
|
47
|
O'Dwyer L, Lamberton F, Matura S, Scheibe M, Miller J, Rujescu D, Prvulovic D, Hampel H. White matter differences between healthy young ApoE4 carriers and non-carriers identified with tractography and support vector machines. PLoS One 2012; 7:e36024. [PMID: 22558310 PMCID: PMC3338494 DOI: 10.1371/journal.pone.0036024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Accepted: 03/26/2012] [Indexed: 11/19/2022] Open
Abstract
The apolipoprotein E4 (ApoE4) is an established risk factor for Alzheimer's disease (AD). Previous work has shown that this allele is associated with functional (fMRI) changes as well structural grey matter (GM) changes in healthy young, middle-aged and older subjects. Here, we assess the diffusion characteristics and the white matter (WM) tracts of healthy young (20-38 years) ApoE4 carriers and non-carriers. No significant differences in diffusion indices were found between young carriers (ApoE4+) and non-carriers (ApoE4-). There were also no significant differences between the groups in terms of normalised GM or WM volume. A feature selection algorithm (ReliefF) was used to select the most salient voxels from the diffusion data for subsequent classification with support vector machines (SVMs). SVMs were capable of classifying ApoE4 carrier and non-carrier groups with an extremely high level of accuracy. The top 500 voxels selected by ReliefF were then used as seeds for tractography which identified a WM network that included regions of the parietal lobe, the cingulum bundle and the dorsolateral frontal lobe. There was a non-significant decrease in volume of this WM network in the ApoE4 carrier group. Our results indicate that there are subtle WM differences between healthy young ApoE4 carriers and non-carriers and that the WM network identified may be particularly vulnerable to further degeneration in ApoE4 carriers as they enter middle and old age.
Collapse
Affiliation(s)
- Laurence O'Dwyer
- Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, Goethe University, Frankfurt, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
48
|
Jochemsen HM, Muller M, van der Graaf Y, Geerlings MI. APOE ε4 differentially influences change in memory performance depending on age. The SMART-MR study. Neurobiol Aging 2012; 33:832.e15-22. [PMID: 21908077 DOI: 10.1016/j.neurobiolaging.2011.07.016] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Revised: 07/11/2011] [Accepted: 07/28/2011] [Indexed: 11/23/2022]
Abstract
The apolipoprotein E (APOE) gene may act differently in young and old persons, known as antagonistic pleiotropy. We therefore examined the prospective associations between the APOE ε4 allele and cognitive functioning, and the modifying effect of age, in 375 nondemented adults (mean age 57 ± 10 years; follow-up period 3.8 ± 0.2 years) with available data on APOE genotype and cognitive functioning, within the SMART-MR (Second Manifestations of ARTerial disease-Magnetic Resonance) cohort study. Neuropsychological tests assessing memory performance and executive functioning were performed at baseline and follow-up, and composite z-scores were calculated. Age significantly modified the association of APOE ε4 with change in memory performance (p interaction = 0.02). In persons ≤ 57 years (median split), an APOE ε4 allele was associated with an increase in immediate recall (B = 0.42; 95% confidence interval [CI], 0.17 to 0.66) and delayed recall (B = 0.37; 95% CI, 0.09 to 0.64), while in persons > 57 years, an APOE ε4 allele was associated with decline in immediate recall (B = -0.25; 95% CI, -0.52 to 0.01). Our findings suggest that the APOE ε4 allele has a differential effect on change in verbal memory performance depending on age, consistent with the hypothesis of antagonistic pleiotropy.
Collapse
|
49
|
Bunce D, Anstey KJ, Burns R, Christensen H, Easteal S. Does possession of apolipoprotein E ɛ4 benefit cognitive function in healthy young adults? Neuropsychologia 2011; 49:1693-7. [PMID: 21396385 DOI: 10.1016/j.neuropsychologia.2011.02.042] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2010] [Revised: 02/18/2011] [Accepted: 02/18/2011] [Indexed: 11/19/2022]
Abstract
There is considerable evidence that the apolipoprotein E (APOE) ɛ4 allele is associated with cognitive deficits in older persons, and is a risk factor for dementia. However, it has recently been suggested that possession of the ɛ4 allele may benefit cognition in early adulthood. We tested this possibility in 5445 community-dwelling persons aged 20-24, 40-44, and 60-64 years using a comprehensive battery of cognitive measures. As the APOE ɛ2 allele may offer protection against cognitive deficits, in order to robustly test the hypothesis, we removed persons carrying this allele from the analyses. Older persons with possible dementia were also removed. We found no evidence of higher cognitive performance in young ɛ4 carriers, or cognitive deficits in older ɛ4 carriers. This did not change when a range of health variables were taken into account. We conclude that it is premature to suppose ɛ4-related benefits to cognition in healthy young adulthood and findings consistent with this hypothesis may have been related to methodological issues, or the pathology of the sample investigated.
Collapse
Affiliation(s)
- David Bunce
- Centre for Cognition and Neuroimaging, Department of Psychology, Brunel University, London, UK.
| | | | | | | | | |
Collapse
|
50
|
Tuminello ER, Han SD. The apolipoprotein e antagonistic pleiotropy hypothesis: review and recommendations. Int J Alzheimers Dis 2011; 2011:726197. [PMID: 21423560 PMCID: PMC3056453 DOI: 10.4061/2011/726197] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2010] [Revised: 01/03/2011] [Accepted: 01/04/2011] [Indexed: 12/27/2022] Open
Abstract
Research on apolipoprotein E (APOE) has consistently revealed a relationship between the gene's ε4 allele and risk for development of Alzheimer's disease (AD). However, research with younger populations of ε4 carriers has suggested that the APOE ε4 allele may in fact be beneficial in earlier ages and may only confer risk of cognitive decline later in life. Accordingly, we and others have proposed that APOE may represent an example of antagonistic pleiotropy. Antagonistic pleiotropy is an evolutionary biology concept that proposes certain genes or alleles that may differentially impact fitness during different life stages. We critically review this hypothesis in light of new research of the impact of APOE on cognition and neural integrity across the lifespan. We provide recommendations for the revision of the antagonistic pleiotropy hypothesis of APOE and suggest important avenues for future research in this area.
Collapse
|