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Igloi K, Marin Bosch B, Kuenzi N, Thomas A, Lauer E, Bringard A, Schwartz S. Interactions between physical exercise, associative memory, and genetic risk for Alzheimer's disease. Cereb Cortex 2024; 34:bhae205. [PMID: 38802684 PMCID: PMC11129939 DOI: 10.1093/cercor/bhae205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 04/26/2024] [Accepted: 05/02/2024] [Indexed: 05/29/2024] Open
Abstract
The ε4 allele of the APOE gene heightens the risk of late onset Alzheimer's disease. ε4 carriers, may exhibit cognitive and neural changes early on. Given the known memory-enhancing effects of physical exercise, particularly through hippocampal plasticity via endocannabinoid signaling, here we aimed to test whether a single session of physical exercise may benefit memory and underlying neurophysiological processes in young ε3 carriers (ε3/ε4 heterozygotes, risk group) compared with a matched control group (homozygotes for ε3). Participants underwent fMRI while learning picture sequences, followed by cycling or rest before a memory test. Blood samples measured endocannabinoid levels. At the behavioral level, the risk group exhibited poorer associative memory performance, regardless of the exercising condition. At the brain level, the risk group showed increased medial temporal lobe activity during memory retrieval irrespective of exercise (suggesting neural compensatory effects even at baseline), whereas, in the control group, such increase was only detectable after physical exercise. Critically, an exercise-related endocannabinoid increase correlated with task-related hippocampal activation in the control group only. In conclusion, healthy young individuals carrying the ε4 allele may present suboptimal associative memory performance (when compared with homozygote ε3 carriers), together with reduced plasticity (and functional over-compensation) within medial temporal structures.
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Affiliation(s)
- Kinga Igloi
- Department of Fundamental Neurosciences, University of Geneva, CH-1211 Geneva, Switzerland
- Swiss Center for Affective Sciences, University of Geneva, CH-1211 Geneva, Switzerland
| | - Blanca Marin Bosch
- Department of Fundamental Neurosciences, University of Geneva, CH-1211 Geneva, Switzerland
| | - Noémie Kuenzi
- Department of Fundamental Neurosciences, University of Geneva, CH-1211 Geneva, Switzerland
| | - Aurélien Thomas
- Faculty Unit of Toxicology, CURML, Faculty of Biology and Medicine, University of Lausanne, CH-1015 Lausanne, Switzerland
- Unit of Forensic Toxicology and Chemistry, CURML, Lausanne and Geneva University Hospitals, Lausanne, CH-1011 Geneva, Switzerland
| | - Estelle Lauer
- Unit of Forensic Toxicology and Chemistry, CURML, Lausanne and Geneva University Hospitals, Lausanne, CH-1011 Geneva, Switzerland
| | - Aurélien Bringard
- Department of Pneumology, Geneva University Hospitals, CH-1011 Geneva, Switzerland
| | - Sophie Schwartz
- Department of Fundamental Neurosciences, University of Geneva, CH-1211 Geneva, Switzerland
- Swiss Center for Affective Sciences, University of Geneva, CH-1211 Geneva, Switzerland
- Geneva Neuroscience Center, University of Geneva, CH-1211 Geneva, Switzerland
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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] [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.
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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
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3
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Lima-Cooper G, Ouma BJ, Datta D, Bond C, Soto AA, Conroy AL, Park GS, Bangirana P, Joloba ML, Opoka RO, Idro R, John CC. Apolipoprotein-E4: risk of severe malaria and mortality and cognitive impairment in pediatric cerebral malaria. Pediatr Res 2023:10.1038/s41390-023-02912-8. [PMID: 38007518 DOI: 10.1038/s41390-023-02912-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 10/21/2023] [Accepted: 11/02/2023] [Indexed: 11/27/2023]
Abstract
BACKGROUND The relationship of apolipoprotein-E4 (APOE4) to mortality and cognition after severe malaria in children is unknown. METHODS APOE genotyping was performed in children with cerebral malaria (CM, n = 261), severe malarial anemia (SMA, n = 224) and community children (CC, n = 213). Cognition was assessed over 2-year follow-up. RESULTS A greater proportion of children with CM or SMA than CC had APOE4 (n = 162, 31.0%; n = 142, 31.7%; n = 103, 24.2%, respectively, p = 0.02), but no difference was seen in APOE3 (n = 310, 59.4%; n = 267, 59.6%; n = 282, 66.2%, respectively, p = 0.06), or APOE2 (n = 50, 9.6%; n = 39, 8.7%; and n = 41, 9.6%, respectively, p = 0.87). APOE4 was associated with increased mortality in CM (odds ratio, 2.28; 95% CI, 1.01, 5.11). However, APOE4 was associated with better long-term cognition (ß, 0.55; 95% CI, 0.04, 1.07, p = 0.04) and attention (ß 0.78; 95% CI, 0.26, 1.30, p = 0.004) in children with CM < 5 years old, but worse attention (ß, -0.90; 95% CI, -1.69, -0.10, p = 0.03) in children with CM ≥ 5 years old. Among children with CM, risk of post-discharge malaria was increased with APOE4 and decreased with APOE3. CONCLUSIONS APOE4 is associated with higher risk of CM or SMA and mortality in children with CM, but better long-term cognition in CM survivors <5 years of age.
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Affiliation(s)
- Giselle Lima-Cooper
- Department of Pediatrics, Ryan White Center for Pediatric Infectious Disease and Global Health, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Benson J Ouma
- Department of Medical Microbiology, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Dibyadyuti Datta
- Department of Pediatrics, Ryan White Center for Pediatric Infectious Disease and Global Health, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Caitlin Bond
- Department of Pediatrics, Ryan White Center for Pediatric Infectious Disease and Global Health, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Alejandro A Soto
- Department of Pediatrics, Ryan White Center for Pediatric Infectious Disease and Global Health, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Andrea L Conroy
- Department of Pediatrics, Ryan White Center for Pediatric Infectious Disease and Global Health, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Gregory S Park
- Office of the Vice President for Research, University of Minnesota, Minneapolis, MN, USA
| | - Paul Bangirana
- Department of Psychiatry, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Moses L Joloba
- Department of Medical Microbiology, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Robert O Opoka
- Department of Pediatrics and Child Health, Makerere University, Kampala, Uganda
| | - Richard Idro
- Department of Pediatrics and Child Health, Makerere University, Kampala, Uganda
- Nuffield Department of Medicine, Centre of Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | - Chandy C John
- Department of Pediatrics, Ryan White Center for Pediatric Infectious Disease and Global Health, Indiana University School of Medicine, Indianapolis, IN, USA.
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Farup PG, Rootwelt H, Hestad K. APOE Polymorphism Is Associated with Changes in the Kynurenine Pathway. Genes (Basel) 2023; 14:1955. [PMID: 37895304 PMCID: PMC10606170 DOI: 10.3390/genes14101955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 10/12/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023] Open
Abstract
BACKGROUND APOE polymorphism and the Kynurenine pathway (KP) are associated with many disorders, but little is known about associations between APOE polymorphism and the KP. This study explored the associations between the KP and APOE polymorphism in disorders associated with APOE polymorphism and changes in the KP. METHODS Subjects with morbid obesity before and after bariatric surgery (numbers 139 and 95, respectively), depression (number 49), and unspecified neurological symptoms (number 39) were included. The following grouping of the APOE genotypes was used: E2 = ɛ2ɛ2 + ɛ2ɛ3, E3 = ɛ3ɛ3 + ɛ2ɛ4, and E4 = ɛ3ɛ4 + ɛ4ɛ4. The KP metabolites Tryptophan, Kynurenine, Kynurenic acid, Quinolinic acid, and Xanthurenic acid were quantified in serum. RESULTS The main findings were a significant positive association between E3 and Quinolinic acid (difference between E3 and E2E4: 12.0 (3.5; 18.6) ng/mL); p = 0.005), and a negative association between E4 and Kynurenine (difference between E4 and E2E3: -31.3 (-54.2; -3.2) ng/mL; p = 0.008). Quinolinic acid has been ascribed neurotoxic and inflammatory effects, and Kynurenine is a marker of inflammation. CONCLUSIONS The findings indicate that APOE polymorphism might cause changes in the KP that contribute to the disease. Inflammation could be the link between APOE and the KP.
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Affiliation(s)
- Per G. Farup
- Department of Research, Innlandet Hospital Trust, 2381 Brumunddal, Norway;
- Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, 7491 Trondheim, Norway
| | - Helge Rootwelt
- Department of Medical Biochemistry, Oslo University Hospital, 0424 Oslo, Norway;
| | - Knut Hestad
- Department of Research, Innlandet Hospital Trust, 2381 Brumunddal, Norway;
- Department of Psychology, Faculty of Social and Educational Sciences, Norwegian University of Science and Technology, 7491 Trondheim, Norway
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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] [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.
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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
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Anderson C, Carmichael J, Hicks AJ, Burke R, Ponsford J. Interaction between APOE ɛ4 and Age Is Associated with Emotional Distress One Year after Moderate-Severe Traumatic Brain Injury. J Neurotrauma 2023; 40:326-336. [PMID: 35996348 DOI: 10.1089/neu.2022.0226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Emotional distress is common following moderate-severe traumatic brain injury (TBI) and is associated with poorer post-injury outcomes. Previously investigated sociodemographic, psychological, and injury-related factors account for only a small proportion of variance in post-TBI emotional distress, highlighting a need to consider other factors such as genetic factors. The apolipoprotein E gene (APOE) has been commonly studied in the TBI literature, with the ɛ4 allele linked to worse neuronal repair and recovery. Few studies have investigated the potential relationship between APOE ɛ4 and emotional distress after moderate-severe TBI, and results have been varied. We examined whether APOE ɛ4 was associated with emotional distress 1 year following moderate-severe TBI, and whether this relationship was moderated by age, sex, and TBI severity (as indexed by the duration of post-traumatic amnesia [PTA]). Moderate-severe TBI survivors provided saliva samples following inpatient admission to a TBI rehabilitation hospital. They completed a self-report measure of emotional distress, the Hospital Anxiety and Depression Scale (HADS), at a follow-up interview ∼1 year post-injury. Complete genetic and follow-up data were available for 441 moderate-severe TBI survivors (mean age = 39.42 years; 75% male). We constructed a linear regression model that included APOE ɛ4 carriage status (carrier vs. non-carrier) and interactions with age, sex, and TBI severity (APOE × age, APOE × sex, APOE × age × sex, and APOE × PTA duration) to predict total score on the HADS, while covarying for the main effects of age, sex, PTA duration, and previous head injury. There was a significant main effect of APOE ɛ4, whereby ɛ4 carriers reported less emotional distress than non-carriers (p = 0.04). However, we also found a significant interaction with age such that APOE ɛ4 carriers reported increasingly greater emotional distress with older age compared with non-carriers (p = 0.01). A sensitivity analysis (n = 306) suggested that the APOE × age interaction, and main effects of age and previous head injury, were not unique to individuals with pre-injury mental health problems (n = 136). However, the main effect of APOE ɛ4 was no longer significant when individuals with pre-injury mental health problems were removed. Our findings highlight the importance of considering moderation of genetic associations, suggesting that APOE ɛ4 may be a risk factor for emotional distress specifically among older survivors of moderate-severe TBI. If these findings can be independently replicated, APOE ɛ4 carriage status, interpreted in the context of age, could be incorporated into risk prediction models of emotional distress after moderate-severe TBI, enhancing targeted early detection and intervention efforts.
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Affiliation(s)
- Chloe Anderson
- Monash-Epworth Rehabilitation Research Centre, Epworth HealthCare, Melbourne, Australia; Turner Institutes for Brain and Mental Health, School of Psychological Sciences, Monash University, Clayton, Victoria, Australia
| | - Jai Carmichael
- Monash-Epworth Rehabilitation Research Centre, Epworth HealthCare, Melbourne, Australia; Turner Institutes for Brain and Mental Health, School of Psychological Sciences, Monash University, Clayton, Victoria, Australia
| | - Amelia J Hicks
- Monash-Epworth Rehabilitation Research Centre, Epworth HealthCare, Melbourne, Australia; Turner Institutes for Brain and Mental Health, School of Psychological Sciences, Monash University, Clayton, Victoria, Australia
| | - Richard Burke
- School of Biological Sciences, Monash University, Clayton, Victoria, Australia
| | - Jennie Ponsford
- Monash-Epworth Rehabilitation Research Centre, Epworth HealthCare, Melbourne, Australia; Turner Institutes for Brain and Mental Health, School of Psychological Sciences, Monash University, Clayton, Victoria, Australia
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Lawrence KA, Rippey CS, Welikson B, Pietrzak RH, Adams TG. Interactive association of posttraumatic stress disorder, apolipoprotein ε4 genotype, and age on cognitive functioning. Int J Geriatr Psychiatry 2023; 38:e5888. [PMID: 36757293 PMCID: PMC10168127 DOI: 10.1002/gps.5888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Accepted: 01/26/2023] [Indexed: 02/04/2023]
Abstract
BACKGROUND The ε4 allele of the apolipoprotein (APOE) gene and posttraumatic stress disorder (PTSD) are associated with cognitive deficits. Both associations may vary depending on age. No previous study has examined a possible three-way interaction between APOE ε4, PTSD, and age on cognitive functioning. METHODS Data were analyzed from 1244 European-American U.S. military veterans who participated in the 2011 National Health and Resilience in Veterans Study (NHRVS). Analyses of covariance were used to examine the main effects and interactions of APOE ε4, PTSD, and age on learning/working memory (LWM) and attention/psychomotor (APM) performance. RESULTS A significant three-way interaction between APOE ε4, PTSD, and age on the LWM composite (ηp 2 = 0.011) was observed such that the main effect of APOE ε4 on LWM was only significant for older participants with PTSD. A significant two-way interaction between PTSD and age on the APM composite (ηp 2 = 0.011) was observed such that the main effect of PTSD on APM was only significant in older participants. CONCLUSION Older APOE ε4 carriers with probable PTSD showed poorer LWM performance relative to other groups. Aging-related associations on APM performance were most pronounced in veterans with PTSD. These data are preliminary evidence that identification and treatment of PTSD may be beneficial for individuals at risk for age-related cognitive impairment.
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Affiliation(s)
| | | | - Bianca Welikson
- University of Louisville, Department of Psychological and Brain Sciences
| | - Robert H. Pietrzak
- Yale School of Medicine, Department of Psychiatry
- Clinical Neurosciences Division, U.S. Department of Veterans Affairs National Center for Posttraumatic Stress Disorder, VA Connecticut Healthcare System
- Yale School of Public Health, Department of Social and Behavioral Sciences
| | - Thomas G. Adams
- University of Kentucky, Department of Psychology
- Yale School of Medicine, Department of Psychiatry
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8
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Crespi B, Yang N. Three laws of teleonometrics. Biol J Linn Soc Lond 2022. [DOI: 10.1093/biolinnean/blac068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Abstract
We define teleonometrics as the theoretical and empirical study of teleonomy. We propose three laws for teleonometrics. The first law describes the hierarchical organization of teleonomic functions across biological levels from genes to individuals. According to this law, the number of goal-directed functions increases from individuals (one goal, maximizing inclusive fitness) to intermediate levels and to genes and alleles (myriad time-, space- and context-dependent goals, depending upon degrees and patterns of pleiotropy). The second law describes the operation of teleonomic functions under trade-offs, coadaptations and negative and positive pleiotropies, which are universal in biological systems. According to this law, the functions of an allele, gene or trait are described and defined by patterns of antagonistic (trading off) and compatible (coadapted) functions. The third law of teleonometrics is that the major transitions in evolution are driven by the origins of novel, emergent goals associated with functional changes and by the breaking and reshaping of trade-offs, especially by mechanisms involving increases in resources or time, and new divisions of labour or function. We illustrate the application of these laws using data from three empirical vignettes, which help to show the usefulness of teleonometric viewpoints for understanding the interfaces between function, trade-offs and dysfunctions manifest as disease.
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Affiliation(s)
- Bernard Crespi
- Department of Biological Sciences, Simon Fraser University , Burnaby, British Columbia, V5A 1S6 , Canada
| | - Nancy Yang
- Department of Biological Sciences, Simon Fraser University , Burnaby, British Columbia, V5A 1S6 , Canada
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Carmichael J, Hicks AJ, Spitz G, Gould KR, Ponsford J. Moderators of gene-outcome associations following traumatic brain injury. Neurosci Biobehav Rev 2021; 130:107-124. [PMID: 34411558 DOI: 10.1016/j.neubiorev.2021.08.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 07/04/2021] [Accepted: 08/13/2021] [Indexed: 12/14/2022]
Abstract
The field of genomics is the principal avenue in the ongoing development of precision/personalised medicine for a variety of health conditions. However, relating genes to outcomes is notoriously complex, especially when considering that other variables can change, or moderate, gene-outcome associations. Here, we comprehensively discuss moderation of gene-outcome associations in the context of traumatic brain injury (TBI), a common, chronically debilitating, and costly neurological condition that is under complex polygenic influence. We focus our narrative review on single nucleotide polymorphisms (SNPs) of three of the most studied genes (apolipoprotein E, brain-derived neurotrophic factor, and catechol-O-methyltransferase) and on three demographic variables believed to moderate associations between these SNPs and TBI outcomes (age, biological sex, and ethnicity). We speculate on the mechanisms which may underlie these moderating effects, drawing widely from biomolecular and behavioural research (n = 175 scientific reports) within the TBI population (n = 72) and other neurological, healthy, ageing, and psychiatric populations (n = 103). We conclude with methodological recommendations for improved exploration of moderators in future genetics research in TBI and other populations.
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Affiliation(s)
- Jai Carmichael
- Monash-Epworth Rehabilitation Research Centre, Epworth HealthCare, Melbourne, Australia; Turner Institute for Brain and Mental Health, School of Psychological Sciences, Monash University, Clayton, Australia.
| | - Amelia J Hicks
- Monash-Epworth Rehabilitation Research Centre, Epworth HealthCare, Melbourne, Australia; Turner Institute for Brain and Mental Health, School of Psychological Sciences, Monash University, Clayton, Australia
| | - Gershon Spitz
- Monash-Epworth Rehabilitation Research Centre, Epworth HealthCare, Melbourne, Australia; Turner Institute for Brain and Mental Health, School of Psychological Sciences, Monash University, Clayton, Australia
| | - Kate Rachel Gould
- Monash-Epworth Rehabilitation Research Centre, Epworth HealthCare, Melbourne, Australia; Turner Institute for Brain and Mental Health, School of Psychological Sciences, Monash University, Clayton, Australia
| | - Jennie Ponsford
- Monash-Epworth Rehabilitation Research Centre, Epworth HealthCare, Melbourne, Australia; Turner Institute for Brain and Mental Health, School of Psychological Sciences, Monash University, Clayton, Australia
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Rao W, Zhang Y, Li K, Zhang XY. Association between cognitive impairment and apolipoprotein A1 or apolipoprotein B levels is regulated by apolipoprotein E variant rs429358 in patients with chronic schizophrenia. Aging (Albany NY) 2021; 13:16353-16366. [PMID: 34135129 PMCID: PMC8266354 DOI: 10.18632/aging.203161] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 05/19/2021] [Indexed: 12/27/2022]
Abstract
ApoE gene polymorphism may be involved in the change in blood lipid profile and cognitive impairment of the general population. However, few studies explored the effects of ApoE gene polymorphism on blood lipid levels and cognition in schizophrenia. The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) was employed to evaluate the cognition and the SNPStats was used to investigate the association of ApoE rs429358 with schizophrenia. The models of analysis of covariance and multivariate analysis were conducted to investigate the effect of ApoE rs429358 on cognition in schizophrenia. Altogether, 637 patients with schizophrenia and 467 healthy controls were recruited in this study. The findings in the case group found that both the ApoA1 and ApoB levels were predictors for RBANS total score (p < 0.001 vs. p = 0.011), immediate memory (p < 0.001 vs. p = 0.019), language (p < 0.001 vs. p = 0.013), attention (p < 0.001 vs. p < 0.001), except ApoA1 level only was a predictor for visuospatial/constructional (p = 0.014) and delayed memory (p < 0.001). When the association was examined in different ApoE rs429358 genotype subgroups, the association between ApoA1 level and RBANS scores (except for the language score) or between ApoB level and RBANS scores (except for the attention score) was regulated by ApoE rs429358. Our results suggest that patients with schizophrenia have broad cognitive impairment compared with healthy controls. For patients with schizophrenia, both ApoA1 and ApoB levels were positively associated with cognition. There was a significant association between ApoA1 or ApoB levels and cognition in schizophrenia, which was regulated by the ApoE rs429358.
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Affiliation(s)
- Wenwang Rao
- Institute of Mental Health, Hebei Mental Health Centre, Hebei Province, China.,Unit of Psychiatry, Department of Public Health and Medicinal Administration & Institute of Translational Medicine, Faculty of Health Sciences, University of Macau, Macao SAR, China
| | - Yunshu Zhang
- Institute of Mental Health, Hebei Mental Health Centre, Hebei Province, China.,Department of Sleep Medicine, Hebei Psychiatric Hospital, Hebei Province, China
| | - Keqing Li
- Institute of Mental Health, Hebei Mental Health Centre, Hebei Province, China.,Department of Sleep Medicine, Hebei Psychiatric Hospital, Hebei Province, China
| | - Xiang Yang Zhang
- CAS Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
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11
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Albrecht DS, Sagare A, Pachicano M, Sweeney MD, Toga A, Zlokovic B, Chui H, Joe E, Schneider L, Morris JC, Benzinger T, Pa J. Early neuroinflammation is associated with lower amyloid and tau levels in cognitively normal older adults. Brain Behav Immun 2021; 94:299-307. [PMID: 33486003 PMCID: PMC8793040 DOI: 10.1016/j.bbi.2021.01.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 01/08/2021] [Accepted: 01/11/2021] [Indexed: 12/15/2022] Open
Abstract
CNS inflammation is a key factor in Alzheimer's Disease (AD), but its relation to pathological Aβ, tau, and APOE4 is poorly understood, particularly prior to the onset of cognitive symptoms. To better characterize early relationships between inflammation, APOE4, and AD pathology, we assessed correlations between cerebrospinal fluid (CSF) inflammatory markers and brain levels of Aβ and tau in cognitively normal older adults. Each participant received a lumbar puncture to collect and quantify CSF levels of TNFα, IL-6, IL-8, and IL-10, a T1-weighted MRI, and PET scanning with [18F]flortaucipir (FTP; n = 57), which binds to tau tangles and/or [18F]florbetapir (FBP; n = 58), which binds to Aβ. Parallel voxelwise regressions assessed relationships between each CSF inflammatory marker and FTP and FBP SUVR, as well as APOE4*CSF inflammation interactions. Unexpectedly, we detected significant negative associations between regional Aβ and tau PET uptake and CSF inflammatory markers. For Aβ PET, we detected negative associations with CSF IL-6 and IL-8 in regions known to show early accumulation of Aβ (i.e. lateral and medial frontal lobes). For tau PET, negative relationships were observed with CSF TNFα and IL-8, predominantly in regions known to exhibit early tau accumulation (i.e. medial temporal lobe). In subsequent analyses, significant interactions between APOE4 status and IL-8 on Aβ and tau PET levels were observed in spatially distinct regions from those showing CSF-Aβ/tau relationships. Results from the current cross-sectional study support previous findings that neuroinflammation may be protective against AD pathology at a given stage of the disease, and extend these findings to a cognitively normal aging population. This study provides new insight into a dynamic relationship between neuroinflammation and AD pathology and may have implications for whom and when neuroinflammatory therapies may be appropriate.
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Affiliation(s)
- Daniel S. Albrecht
- Mark and Mary Stevens Neuroimaging and Informatics Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033, United States
| | - Abhay Sagare
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033, United States
| | - Maricarmen Pachicano
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033, United States
| | - Melanie D. Sweeney
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033, United States
| | - Arthur Toga
- Mark and Mary Stevens Neuroimaging and Informatics Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033, United States
| | - Berislav Zlokovic
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033, United States
| | - Helena Chui
- Alzheimer Disease Research Center, Department of Neurology, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033, United States
| | - Elizabeth Joe
- Alzheimer Disease Research Center, Department of Neurology, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033, United States
| | - Lon Schneider
- Alzheimer Disease Research Center, Department of Neurology, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033, United States
| | - John C. Morris
- Department of Neurology, Department of Radiology, and Division of Biostatistics, Washington University School of Medicine, St Louis, MO, United States
| | - Tammie Benzinger
- Department of Neurology, Department of Radiology, and Division of Biostatistics, Washington University School of Medicine, St Louis, MO, United States
| | - Judy Pa
- Mark and Mary Stevens Neuroimaging and Informatics Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033, United States; Alzheimer Disease Research Center, Department of Neurology, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90033, United States.
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12
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Genetics of synucleins in neurodegenerative diseases. Acta Neuropathol 2021; 141:471-490. [PMID: 32740728 DOI: 10.1007/s00401-020-02202-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [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.
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13
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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] [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.
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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.
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14
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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 RESEARCH & THERAPY 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] [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.
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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.
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15
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Cognitive changes in patient living with HIV-AIDS and apolipoprotein-E polymorphism: is there an association? Mol Biol Rep 2020; 47:8757-8762. [PMID: 33085049 DOI: 10.1007/s11033-020-05923-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 10/11/2020] [Accepted: 10/13/2020] [Indexed: 10/23/2022]
Abstract
Patients with HIV-AIDS treated with antiretroviral drugs still have high prevalence of cognitive disorders and many factors are likely to contribute for ongoing neurologic decline such as chronic low-level infection, coinfections with hepatitis B and C and genetic influences, both the virus and the host. Some evidences suggest that the genetic APOE polymorphism may be an associated risk factor. This study aimed to evaluate the association between APOE polymorphisms and cognitive disorders in patients with HIV-AIDS. This was a cross-sectional study comprising 133 patients aged 19-59 years old, with HIV-AIDS and were assisted at the infectious disease outpatient clinics at Hospital Universitário Oswaldo Cruz, in Recife, Brazil. For cognitive evaluation, Mini-Mental State Examination test (MMSE) and Montreal Cognitive Assessment test (MoCA) were used. The determination of APOE gene polymorphism was performed by using the PCR-RFLP technique. Sociodemographic and clinical characteristics were not significantly associated to APOE ε4 polymorphism, except for the high results of CD4 rate (p < 0.015). There was an absence associated between APOE ε4 polymorphism and neurocognitive tests. This study found no association between cognitive alterations and APOE polymorphism in patients with HIV-AIDS in the Northeast of Brazil. The imbalance of APOE allelic frequency distribution, according to Hardy-Weinberg law, there could be an adjustment phase of its equilibrium suffered by the HIV virus, however, the mechanism is still unknown.
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16
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Superior short-term memory in APOE ε2 carriers across the age range. Behav Brain Res 2020; 397:112918. [PMID: 32961217 PMCID: PMC7732594 DOI: 10.1016/j.bbr.2020.112918] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 09/03/2020] [Accepted: 09/11/2020] [Indexed: 11/20/2022]
Abstract
The Apolipoprotein-E (APOE) ε2 allele is known to be protective against Alzheimer’s disease. We tested the effect of this allele on cognitive performance, as measured by a sensitive short-term memory task. A large cohort of genotyped participants performed this task remotely. ε2 carriers demonstrated superior memory performance in young, middle-aged, and older participants.
The Apolipoprotein-E (APOE) gene is now known to be associated with individual differences in cognitive health in ageing. However, while the APOE ε4 allele confers significantly increased risk of developing Alzheimer’s disease (AD), the APOE ε2 allele is hypothesized to be protective against the development of AD. This is in line with neuroimaging and pathological findings associated with ε2 APOE allele, which go in the opposite direction to those observed in AD-related pathology. However, the precise impact of this allele on cognition remains inconclusive, with some small-cohort studies raising the possibility of an advantageous memory performance in these individuals. Here, we tested short-term memory (STM) performance in a large cohort of individuals, 300 of which were ε2/ε3 carriers. Their performance was compared to 554 ε3/ε3 carriers. We included participants from a wide age range spanning young, middle-aged and elderly adults. All of them performed a STM task that has previously been shown to be sensitive to subtle changes in memory in various patient and at-risk cohorts. Individuals carrying the APOE-ε2 allele exhibited a significant memory advantage, regardless of STM task difficulty and across all ages. The observed memory advantage was present across the age range, suggestive of a phenotypical effect of this allele on cognition, possibly independent of any effects of this genetic allele that occur later life in these individuals.
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17
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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] [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.
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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
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18
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Kulkarni P, Grant S, Morrison TR, Cai X, Iriah S, Kristal BS, Honeycutt J, Brenhouse H, Hartner JC, Madularu D, Ferris CF. Characterizing the human APOE epsilon 4 knock-in transgene in female and male rats with multimodal magnetic resonance imaging. Brain Res 2020; 1747:147030. [PMID: 32745658 DOI: 10.1016/j.brainres.2020.147030] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 06/23/2020] [Accepted: 07/22/2020] [Indexed: 12/12/2022]
Abstract
The APOE Ɛ4 genotype is the most prevalent genetic risk for Alzheimer's disease (AD). Women carriers of Ɛ4 have higher risk for an early onset of AD than men. Human imaging studies suggest apolipoprotein Ɛ4 may affect brain structures associated with cognitive decline in AD many years before disease onset. It was hypothesized that female APOE Ɛ4 carriers would present with decreased cognitive function and neuroradiological evidence of early changes in brain structure and function as compared to male carriers. Six-month old wild-type (WT) and human APOE Ɛ4 knock-in (TGRA8960), male and female Sprague Dawley rats were studied for changes in brain structure using voxel-based morphometry, alteration in white and gray matter microarchitecture using diffusion weighted imaging with indices of anisotropy, and functional coupling using resting state BOLD functional connectivity. Images from each modality were registered to, and analyzed, using a 3D MRI rat atlas providing site-specific data on over 168 different brain areas. Quantitative volumetric analysis revealed areas involved in memory and arousal were significantly different between Ɛ4 and wild-type (WT) females, with few differences between male genotypes. Diffusion weighted imaging showed few differences between WT and Ɛ4 females, while male genotypes showed significant different measures in fractional anisotropy and apparent diffusion coefficient. Resting state functional connectivity showed Ɛ4 females had greater connectivity between areas involved in cognition, emotion, and arousal compared to WT females, with male Ɛ4 showing few differences from controls. Interestingly, male Ɛ4 showed increased anxiety and decreased performance in spatial and episodic memory tasks compared to WT males, with female genotypes showing little difference across behavioral tests. The sex differences in behavior and diffusion weighted imaging suggest male carriers of the Ɛ4 allele may be more vulnerable to cognitive and emotional complications compared to female carriers early in life. Conversely, the data may also suggest that female carriers are more resilient to cognitive/emotional problems at this stage of life perhaps due to altered brain volumes and enhanced connectivity.
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Affiliation(s)
- Praveen Kulkarni
- Northeastern Univ, Center for Translational NeuroImaging, Boston, MA, United States
| | - Simone Grant
- Dept of Psychiatry and Neurosciences, Univ California at Davis, United States
| | - Thomas R Morrison
- Northeastern Univ, Center for Translational NeuroImaging, Boston, MA, United States
| | - Xuezhu Cai
- Northeastern Univ, Center for Translational NeuroImaging, Boston, MA, United States
| | - Sade Iriah
- Northeastern Univ, Center for Translational NeuroImaging, Boston, MA, United States
| | - Bruce S Kristal
- Dept Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States
| | | | | | | | - Dan Madularu
- Northeastern Univ, Center for Translational NeuroImaging, Boston, MA, United States
| | - Craig F Ferris
- Northeastern Univ, Center for Translational NeuroImaging, Boston, MA, United States; Northeastern Univ, Dept. Pharmaceutical Sciences, Boston, MA, United States.
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19
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Malykhin NV, Travis S, Fujiwara E, Huang Y, Camicioli R, Olsen F. The associations of the
BDNF
and
APOE
polymorphisms, hippocampal subfield volumes, and episodic memory performance across the lifespan. Hippocampus 2020; 30:1081-1097. [DOI: 10.1002/hipo.23217] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 03/23/2020] [Accepted: 04/25/2020] [Indexed: 12/14/2022]
Affiliation(s)
- Nikolai V. Malykhin
- Neuroscience and Mental Health Institute University of Alberta Edmonton Alberta Canada
- Department of Biomedical Engineering University of Alberta Edmonton Alberta Canada
- Department of Psychiatry University of Alberta Edmonton Alberta Canada
| | - Scott Travis
- Neuroscience and Mental Health Institute University of Alberta Edmonton Alberta Canada
| | - Esther Fujiwara
- Neuroscience and Mental Health Institute University of Alberta Edmonton Alberta Canada
- Department of Psychiatry University of Alberta Edmonton Alberta Canada
| | - Yushan Huang
- Department of Biomedical Engineering University of Alberta Edmonton Alberta Canada
| | | | - Fraser Olsen
- Department of Biomedical Engineering University of Alberta Edmonton Alberta Canada
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20
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Zokaei N, Grogan J, Fallon SJ, Slavkova E, Hadida J, Manohar S, Nobre AC, Husain M. Short-term memory advantage for brief durations in human APOE ε4 carriers. Sci Rep 2020; 10:9503. [PMID: 32528115 PMCID: PMC7289888 DOI: 10.1038/s41598-020-66114-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Accepted: 05/07/2020] [Indexed: 12/19/2022] Open
Abstract
The Apolipoprotein-E (APOE) ε4 gene allele, the highest known genetic risk factor for Alzheimer's disease, has paradoxically been well preserved in the human population. One possible explanation offered by evolutionary biology for survival of deleterious genes is antagonistic pleiotropy. This theory proposes that such genetic variants might confer an advantage, even earlier in life when humans are also reproductively fit. The results of some small-cohort studies have raised the possibility of such a pleiotropic effect for the ε4 allele in short-term memory (STM) but the findings have been inconsistent. Here, we tested STM performance in a large cohort of individuals (N = 1277); nine hundred and fifty-nine of which included carrier and non-carriers of the APOE ε4 gene, those at highest risk of developing Alzheimer's disease. We first confirm that this task is sensitive to subtle deterioration in memory performance across ageing. Importantly, individuals carrying the APOE ε4 gene actually exhibited a significant memory advantage across all ages, specifically for brief retention periods but crucially not for longer durations. Together, these findings present the strongest evidence to date for a gene having an antagonistic pleiotropy effect on human cognitive function across a wide age range, and hence provide an explanation for the survival of the APOE ε4 allele in the gene pool.
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Affiliation(s)
- Nahid Zokaei
- Oxford Centre for Human Brain Activity, Wellcome Centre for Integrative Neuroimaging, Department of Psychiatry, University of Oxford, Oxford, OX3 7JX, UK.
- Department of Experimental Psychology, University of Oxford, Oxford, OX1 3UD, UK.
| | - John Grogan
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 9DU, UK
| | - Sean James Fallon
- National Institute for Health Research Bristol Biomedical Research Centre, University Hospitals Bristol NHS foundation Trust and University of Bristol, Oxford, UK
| | - Ellie Slavkova
- Department of Experimental Psychology, University of Oxford, Oxford, OX1 3UD, UK
| | - Jonathan Hadida
- Oxford Centre for Human Brain Activity, Wellcome Centre for Integrative Neuroimaging, Department of Psychiatry, University of Oxford, Oxford, OX3 7JX, UK
| | - Sanjay Manohar
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 9DU, UK
| | - Anna Christina Nobre
- Oxford Centre for Human Brain Activity, Wellcome Centre for Integrative Neuroimaging, Department of Psychiatry, University of Oxford, Oxford, OX3 7JX, UK
- Department of Experimental Psychology, University of Oxford, Oxford, OX1 3UD, UK
| | - Masud Husain
- Department of Experimental Psychology, University of Oxford, Oxford, OX1 3UD, UK
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, OX3 9DU, UK
- Oxford NIHR Biomedical Research Centre, Oxford, UK
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21
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Abstract
Between the 1930s and 1950s, scientists developed key principles of population genetics to try and explain the aging process. Almost a century later, these aging theories, including antagonistic pleiotropy and mutation accumulation, have been experimentally validated in animals. Although the theories have been much harder to test in humans despite research dating back to the 1970s, recent research is closing this evidence gap. Here we examine the strength of evidence for antagonistic pleiotropy in humans, one of the leading evolutionary explanations for the retention of genetic risk variation for non-communicable diseases. We discuss the analytical tools and types of data that are used to test for patterns of antagonistic pleiotropy and provide a primer of evolutionary theory on types of selection as a guide for understanding this mechanism and how it may manifest in other diseases. We find an abundance of non-experimental evidence for antagonistic pleiotropy in many diseases. In some cases, several studies have independently found corroborating evidence for this mechanism in the same or related sets of diseases including cancer and neurodegenerative diseases. Recent studies also suggest antagonistic pleiotropy may be involved in cardiovascular disease and diabetes. There are also compelling examples of disease risk variants that confer fitness benefits ranging from resistance to other diseases or survival in extreme environments. This provides increasingly strong support for the theory that antagonistic pleiotropic variants have enabled improved fitness but have been traded for higher burden of disease later in life. Future research in this field is required to better understand how this mechanism influences contemporary disease and possible consequences for their treatment.
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22
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Large-scale cortical travelling waves predict localized future cortical signals. PLoS Comput Biol 2019; 15:e1007316. [PMID: 31730613 PMCID: PMC6894364 DOI: 10.1371/journal.pcbi.1007316] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 11/27/2019] [Accepted: 07/31/2019] [Indexed: 12/15/2022] Open
Abstract
Predicting future brain signal is highly sought-after, yet difficult to achieve.
To predict the future phase of cortical activity at localized ECoG and MEG
recording sites, we exploit its predominant, large-scale, spatiotemporal
dynamics. The dynamics are extracted from the brain signal through Fourier
analysis and principal components analysis (PCA) only, and cast in a data model
that predicts future signal at each site and frequency of interest. The dominant
eigenvectors of the PCA that map the large-scale patterns of past cortical phase
to future ones take the form of smoothly propagating waves over the entire
measurement array. In ECoG data from 3 subjects and MEG data from 20 subjects
collected during a self-initiated motor task, mean phase prediction errors were
as low as 0.5 radians at local sites, surpassing state-of-the-art methods of
within-time-series or event-related models. Prediction accuracy was highest in
delta to beta bands, depending on the subject, was more accurate during episodes
of high global power, but was not strongly dependent on the time-course of the
task. Prediction results did not require past data from the to-be-predicted
site. Rather, best accuracy depended on the availability in the model of long
wavelength information. The utility of large-scale, low spatial frequency
traveling waves in predicting future phase activity at local sites allows
estimation of the error introduced by failing to account for irreducible
trajectories in the activity dynamics. Prediction is an important step in scientific progress, often leading to
real-world applications. Prediction of future brain activity could lead to
improvements in detecting driver and pilot error or real-time brain testing
using transcranial magnetic stimulation. Previous studies have either supposed
that the ‘noise’ level in the cortex is high, setting the prediction bar rather
low; or used localized measurements to predict future activity, with modest
success. A long-held but controversial hypothesis is that the cortex is best
characterized as a multi-scale dynamic structure, in which the flow of activity
at one scale, say, the area responsible for motor control, is inextricably tied
to activity at smaller and larger scales, for example within a cortical column
and the whole cortex. We test this hypothesis by analyzing large-scale traveling
waves of cortical activity. Like waves arriving on a beach, the ongoing wave
motion allows better prediction of future activity compared to monitoring the
local rise and fall; in the best cases the future wave cycle is predicted with
as low as 20° average error angle. The prediction techniques developed for the
present research rely on mathematics related to quantifying large-scale weather
patterns or analysis of fluid dynamics.
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23
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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] [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.
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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
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24
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Cognitive Performance in Young APOE ε4 Carriers: A Latent Variable Approach for Assessing the Genotype-Phenotype Relationship. Behav Genet 2019; 49:455-468. [PMID: 31177340 DOI: 10.1007/s10519-019-09961-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [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.
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25
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Responses to executive demand in young adulthood differ by APOE genotype. Behav Brain Res 2019; 360:158-168. [PMID: 30472114 DOI: 10.1016/j.bbr.2018.11.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [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.
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26
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Hodgetts CJ, Shine JP, Williams H, Postans M, Sims R, Williams J, Lawrence AD, Graham KS. Increased posterior default mode network activity and structural connectivity in young adult APOE-ε4 carriers: a multimodal imaging investigation. Neurobiol Aging 2019; 73:82-91. [PMID: 30339963 PMCID: PMC6261847 DOI: 10.1016/j.neurobiolaging.2018.08.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 08/15/2018] [Accepted: 08/16/2018] [Indexed: 12/18/2022]
Abstract
Young adult APOE-ε4 carriers show increased activity in posterior regions of the default mode network (pDMN), but how this is related to structural connectivity is unknown. Thirty young adults (one half of whom were APOE-ε4 carriers; mean age 20 years) were scanned using both diffusion and functional magnetic resonance imaging. The parahippocampal cingulum bundle (PHCB)-which links the pDMN and the medial temporal lobe-was manually delineated in individual participants using deterministic tractography. Measures of tract microstructure (mean diffusivity and fractional anisotropy) were then extracted from these tract delineations. APOE-ε4 carriers had lower mean diffusivity and higher fractional anisotropy relative to noncarriers in PHCB, but not in a control tract (the inferior longitudinal fasciculus). Furthermore, PHCB microstructure was selectively associated with pDMN (and medial temporal lobe) activity during a scene discrimination task known to be sensitive to Alzheimer's disease. These findings are consistent with a lifespan view of Alzheimer's disease risk, where early-life, connectivity-related changes in specific, vulnerable "hubs" (e.g., pDMN) lead to increased neural activity. Critically, such changes may reflect reduced network efficiency/flexibility in APOE-ε4 carriers, which in itself may portend a faster decline in connectivity over the lifespan and ultimately trigger early amyloid-β deposition in later life.
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Affiliation(s)
- Carl J Hodgetts
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Cardiff, Wales, UK.
| | - Jonathan P Shine
- German Center for Neurodegenerative Diseases (DZNE), Aging and Cognition Research Group, Magdeburg, Germany
| | - Huw Williams
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Cardiff, Wales, UK
| | - Mark Postans
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Cardiff, Wales, UK
| | - Rebecca Sims
- Institute of Psychological Medicine and Clinical Neurosciences, MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, Wales, UK
| | - Julie Williams
- Institute of Psychological Medicine and Clinical Neurosciences, MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, Wales, UK; Dementia Research Institute, Cardiff University, Cardiff, Wales, UK
| | - Andrew D Lawrence
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Cardiff, Wales, UK
| | - Kim S Graham
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Cardiff, Wales, UK
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27
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Zink N, Bensmann W, Arning L, Beste C, Stock AK. Apolipoprotein ε4 is associated with better cognitive control allocation in healthy young adults. Neuroimage 2018; 185:274-285. [PMID: 30342978 DOI: 10.1016/j.neuroimage.2018.10.046] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 09/30/2018] [Accepted: 10/17/2018] [Indexed: 11/20/2022] Open
Abstract
Many gene variants may impair our health and cognitive abilities at old age, but some of them paradoxically improve the same or similar functions at much younger age (antagonistic pleiotropy hypothesis). Such a diametric pattern may also hold true for the ancestral Apolipoprotein E (APOE) ε4 allele, which increases the risk for Alzheimer's disease and cognitive decline in old age, but may benefit (pre)frontal (executive) functions in young carriers. We therefore investigated potential cognitive benefits of the risk allele on cognitive control capacities and top-down control allocation ("metacontrol") in n = 190 healthy young adults. On a behavioral level, we found young APOE ε4 carriers to better adapt to different degrees of cognitive control requirements, with superior performance in case of high control demands. On a neurophysiological level, these group differences were reflected by modulations of the N450 component, which were rooted in activation differences of the superior frontal gyrus (SFG, BA8). Taken together, our results suggest that young ε4 carriers are more efficient than non-carriers at allocating cognitive control resources based on the actual task requirements (i.e. metacontrol), as they seem to experience less conflict/exert less effort and recruit fewer additional prefrontal areas when task set complexity increases. We further found that ε2 carriers processed implicit spatial stimulus features to a stronger degree than ε3 and ε4 carriers, but failed to benefit from this, as the additional information likely increased response selection conflicts. This finding should however be treated with ample caution as the group of ε2 carriers was comparatively small.
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Affiliation(s)
- Nicolas Zink
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine of the TU Dresden, Germany
| | - Wiebke Bensmann
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine of the TU Dresden, Germany
| | - Larissa Arning
- Department of Human Genetics, Ruhr-University Bochum, Bochum, Germany
| | - Christian Beste
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine of the TU Dresden, Germany
| | - Ann-Kathrin Stock
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine of the TU Dresden, Germany.
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28
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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] [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.
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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
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29
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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] [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.
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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
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30
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O'Donoghue MC, Murphy SE, Zamboni G, Nobre AC, Mackay CE. APOE genotype and cognition in healthy individuals at risk of Alzheimer's disease: A review. Cortex 2018; 104:103-123. [DOI: 10.1016/j.cortex.2018.03.025] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 02/02/2018] [Accepted: 03/19/2018] [Indexed: 01/22/2023]
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31
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Intrinsic functional connectivity alterations in cognitively intact elderly APOE ε4 carriers measured by eigenvector centrality mapping are related to cognition and CSF biomarkers: a preliminary study. Brain Imaging Behav 2018; 11:1290-1301. [PMID: 27714554 DOI: 10.1007/s11682-016-9600-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Apolipoprotein E (APOE) ε4 allele is the best established genetic risk factor for sporadic Alzheimer's disease (AD). However, there is a need to understand the effects of this genotype on the brain by simultaneously assessing intrinsic brain network and cerebral spinal fluid (CSF) biomarkers changes in healthy older ε4 carriers. Thirteen cognitively intact, elderly APOE ε4 carriers and 22 ε3 homozygotes were included in the present study. Eigenvector centrality mapping (ECM) was used to identify brain network hub organization based on resting-state functional MRI (rsfMRI). We evaluated comprehensive cognitive ability and tested levels of Aβ1-42, total-tau (t-tau) and phosphorylated-tau (p-tau181) in CSF. Comparisons of ECM between two groups were conducted, followed by correlations analyses between EC values with significant group differences and cognitive ability/CSF biomarkers. APOE ε4 carriers showed significantly decreased EC values in left medial temporal lobe (MTL), left lingual gyrus (LG) and increased EC values in left middle frontal gyrus (MFG) as compared to non-carriers. Correlation analysis demonstrated that left LG EC value correlated with Rey Auditory Verbal Learning Test total learning (RAVLT, r = 0.57, p < 0.05) and t-tau level (r = -0.57, p < 0.05), while left MFG EC values correlated with log-transformed Trail-Making Test B (TMT-B, r = -0.67, p < 0.05) in APOE ε4 carriers. This study suggests the APOE ε4 allele contributes to disruption of brain connectedness in certain functional nodes, which may result from neuronal death caused by toxicity of neurofibrillary tangles.
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32
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Luo X, Li K, Jia YL, Zeng Q, Jiaerken Y, Qiu T, Huang P, Xu X, Shen Z, Guan X, Zhou J, Wang C, Xu JJ, Zhang M. Altered effective connectivity anchored in the posterior cingulate cortex and the medial prefrontal cortex in cognitively intact elderly APOE ε4 carriers: a preliminary study. Brain Imaging Behav 2018; 13:270-282. [DOI: 10.1007/s11682-018-9857-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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33
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Forero DA, López-León S, González-Giraldo Y, Dries DR, Pereira-Morales AJ, Jiménez KM, Franco-Restrepo JE. APOE gene and neuropsychiatric disorders and endophenotypes: A comprehensive review. Am J Med Genet B Neuropsychiatr Genet 2018; 177:126-142. [PMID: 27943569 DOI: 10.1002/ajmg.b.32516] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 11/07/2016] [Indexed: 12/14/2022]
Abstract
The Apolipoprotein E (APOE) gene is one of the main candidates in neuropsychiatric genetics, with hundreds of studies carried out in order to explore the possible role of polymorphisms in the APOE gene in a large number of neurological diseases, psychiatric disorders, and related endophenotypes. In the current article, we provide a comprehensive review of the structural and functional aspects of the APOE gene and its relationship with brain disorders. Evidence from genome-wide association studies and meta-analyses shows that the APOE gene has been significantly associated with several neurodegenerative disorders. Cellular and animal models show growing evidence of the key role of APOE in mechanisms of brain plasticity and behavior. Future analyses of the APOE gene might find a possible role in other neurological diseases and psychiatric disorders and related endophenotypes. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Diego A Forero
- Laboratory of Neuropsychiatric Genetics, Biomedical Sciences Research Group, School of Medicine, Universidad Antonio Nariño, Bogotá, Colombia.,PhD Program in Health Sciences, School of Medicine, Universidad Antonio Nariño, Bogotá, Colombia
| | | | - Yeimy González-Giraldo
- Departamento de Nutrición y Bioquímica, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Daniel R Dries
- Chemistry Department, Juniata College, Huntingdon, Pennsylvania
| | - Angela J Pereira-Morales
- Laboratory of Neuropsychiatric Genetics, Biomedical Sciences Research Group, School of Medicine, Universidad Antonio Nariño, Bogotá, Colombia
| | - Karen M Jiménez
- Laboratory of Neuropsychiatric Genetics, Biomedical Sciences Research Group, School of Medicine, Universidad Antonio Nariño, Bogotá, Colombia
| | - Juan E Franco-Restrepo
- PhD Program in Health Sciences, School of Medicine, Universidad Antonio Nariño, Bogotá, Colombia
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34
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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] [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.
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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
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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] [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.
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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
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Sinclair LI, Pleydell-Pearce CW, Day INM. Possible positive effect of the APOE ε2 allele on cognition in early to mid-adult life. Neurobiol Learn Mem 2017; 146:37-46. [PMID: 29032015 PMCID: PMC5725639 DOI: 10.1016/j.nlm.2017.10.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 09/27/2017] [Accepted: 10/07/2017] [Indexed: 01/28/2023]
Abstract
E4 carriers self reported more memory problems, but no objective differences found. E2 carriers performed slightly better on episodic memory test. E2 carriers were faster in a test of executive function.
Background ε4 allele possession is associated with an increased risk of Alzheimer’s disease. Its effects earlier in life are less well understood. Previous studies have reported both detrimental effects and a lack of effect on cognition outside dementia. We used genotype based recall from the ALSPAC study to investigate whether APOE genotype influences cognition in earlier adult life. Methods We invited all individuals with the rarer ε22 or ε44 genotypes and equal numbers of those with ε32, ε33 or ε34 APOE genotypes (total n invited = 1936, ages 23–67). Participants were screened for dementia using the Addenbrooke’s Cognitive Examination Revised (ACE-R). Participants were asked to complete a 3 h battery of neuropsychological tests covering a range of cognitive domains. The primary outcome was performance on the Rey Auditory Verbal Learning Test (RAVLT). Transformation of variables was used where required to permit parametric testing. As genotypes are unlikely to be confounded unadjusted analyses were performed. Results 114 participants were recruited to the study (39 ε33, 27 ε34, 15 ε44, 26 ε32 & 7 ε22). ε4+ participants had higher scores on the cognitive failures questionnaire (10 point increase, p = 0.006) but no deficits on objective cognitive testing. ε2 carriers had slightly better episodic memory performance (p = 0.016), slightly improved n-back accuracy and better executive functioning (trails A&B, p = 0.005). Conclusions It is intriguing that the ε2+ group performed better as this group have a lower risk of Alzheimer’s disease. Most previous studies have analysed as ε4/non ε4 so may have missed this effect.
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Affiliation(s)
- Lindsey I Sinclair
- School of Social and Community Medicine, University of Bristol, Oakfield House, Bristol BS8 2BN, UK.
| | - Christopher W Pleydell-Pearce
- School of Experimental Psychology, University of Bristol, The Priory Road Complex, Priory Road, Bristol BS8 1TU, UK.
| | - Ian N M Day
- School of Social and Community Medicine, University of Bristol, Oakfield House, Bristol BS8 2BN, UK
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Huebbe P, Rimbach G. Evolution of human apolipoprotein E (APOE) isoforms: Gene structure, protein function and interaction with dietary factors. Ageing Res Rev 2017. [PMID: 28647612 DOI: 10.1016/j.arr.2017.06.002] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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.
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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.
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38
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APOE moderates compensatory recruitment of neuronal resources during working memory processing in healthy older adults. Neurobiol Aging 2017; 56:127-137. [PMID: 28528773 DOI: 10.1016/j.neurobiolaging.2017.04.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 03/17/2017] [Accepted: 04/13/2017] [Indexed: 11/20/2022]
Abstract
The APOE ε4 allele increases the risk for sporadic Alzheimer's disease and modifies brain activation patterns of numerous cognitive domains. We assessed cognitively intact older adults with a letter n-back task to determine if previously observed increases in ε4 carriers' working-memory-related brain activation are compensatory such that they serve to maintain working memory function. Using multiple regression models, we identified interactions of APOE variant and age in bilateral hippocampus independently from task performance: ε4 carriers only showed a decrease in activation with increasing age, suggesting high sensitivity of fMRI data for detecting changes in Alzheimer's disease-relevant brain areas before cognitive decline. Moreover, we identified ε4 carriers to show higher activations in task-negative medial and task-positive inferior frontal areas along with better performance under high working memory load relative to non-ε4 carriers. The increased frontal recruitment is compatible with models of neuronal compensation, extends on existing evidence, and suggests that ε4 carriers require additional neuronal resources to successfully perform a demanding working memory task.
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39
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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).
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Kulminski AM, Kernogitski Y, Culminskaya I, Loika Y, Arbeev KG, Bagley O, Duan M, Arbeeva L, Ukraintseva SV, Wu D, Stallard E, Yashin AI. Uncoupling associations of risk alleles with endophenotypes and phenotypes: insights from the ApoB locus and heart-related traits. Aging Cell 2017; 16:61-72. [PMID: 27683205 PMCID: PMC5242299 DOI: 10.1111/acel.12526] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/10/2016] [Indexed: 12/04/2022] Open
Abstract
Traditionally, genomewide association studies (GWAS) have emphasized the benefits of large samples in the analyses of age‐related traits rather than their specific properties. We adopted a realistic concept of genetic susceptibility to inherently heterogeneous, age‐related traits driven by the elusive role of evolution in their properties. We analyzed in detail the associations of rs693 and rs562338 polymorphisms representing the Apolipoprotein B locus with endophenotypes (total cholesterol [TC] and high‐density lipoprotein cholesterol) and phenotypes (myocardial infarction [MI] and survival) in four large‐scale studies, which include 20 748 individuals with 2357 MI events. We showed that a strong, robust predisposition of rs693 and rs562338 to TC (β = 0.72, P = 7.7 × 10−30 for rs693 and β = −1.08, P = 9.8 × 10−42 for rs562338) is not translated into a predisposition to MI and survival. The rs693_A allele influences risks of MI and mortality after MI additively with lipids. This allele shows antagonistic effects—protecting against MI risks (β = −0.18, P = 1.1 × 10−5) or increasing MI risks (β = 0.15, P = 2.8 × 10−3) and mortality after MI, in different populations. Paradoxically, increased TC concentrations can be protective against MI for the rs693_A allele carriers. Our results uncouple the influences of the same alleles on endophenotypes and phenotypes despite potential causal relationships among the latter. Our strategy reveals virtually genomewide significance for the associations of rs693 with MI (P = 5.5 × 10−8) that is contrasted with a weak estimate following the traditional, sample‐size‐centered GWAS strategy (P = 0.16) in the same sample. These results caution against the use of the traditional GWAS strategy for gaining profound insights into genetic predisposition to healthspan and lifespan.
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Affiliation(s)
- Alexander M. Kulminski
- Biodemography of Aging Research Unit; Social Science Research Institute; Duke University; Durham NC 27708-0408 USA
| | - Yelena Kernogitski
- Biodemography of Aging Research Unit; Social Science Research Institute; Duke University; Durham NC 27708-0408 USA
| | - Irina Culminskaya
- Biodemography of Aging Research Unit; Social Science Research Institute; Duke University; Durham NC 27708-0408 USA
| | - Yury Loika
- Biodemography of Aging Research Unit; Social Science Research Institute; Duke University; Durham NC 27708-0408 USA
| | - Konstantin G. Arbeev
- Biodemography of Aging Research Unit; Social Science Research Institute; Duke University; Durham NC 27708-0408 USA
| | - Olivia Bagley
- Biodemography of Aging Research Unit; Social Science Research Institute; Duke University; Durham NC 27708-0408 USA
| | - Matt Duan
- Biodemography of Aging Research Unit; Social Science Research Institute; Duke University; Durham NC 27708-0408 USA
| | - Liubov Arbeeva
- Biodemography of Aging Research Unit; Social Science Research Institute; Duke University; Durham NC 27708-0408 USA
| | - Svetlana V. Ukraintseva
- Biodemography of Aging Research Unit; Social Science Research Institute; Duke University; Durham NC 27708-0408 USA
| | - Deqing Wu
- Biodemography of Aging Research Unit; Social Science Research Institute; Duke University; Durham NC 27708-0408 USA
| | - Eric Stallard
- Biodemography of Aging Research Unit; Social Science Research Institute; Duke University; Durham NC 27708-0408 USA
| | - Anatoliy I. Yashin
- Biodemography of Aging Research Unit; Social Science Research Institute; Duke University; Durham NC 27708-0408 USA
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Chang P, Li X, Ma C, Zhang S, Liu Z, Chen K, Ai L, Chang J, Zhang Z. The Effects of an APOE Promoter Polymorphism on Human White Matter Connectivity during Non-Demented Aging. J Alzheimers Dis 2016; 55:77-87. [DOI: 10.3233/jad-160447] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
- Peifen Chang
- Dongzhimen Hospital, Beijing university of Chinese Medicine, Beijing, P.R. China
| | - Xin Li
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, P.R. China
| | - Chao Ma
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, P.R. China
| | - Sisi Zhang
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, P.R. China
| | - Zhen Liu
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, P.R. China
| | - Kewei Chen
- Banner Alzheimer’s Institute, Phoenix, AZ, USA
| | - Lin Ai
- Department of Radiology, Beijing Tiantan Hospital, Beijing Neurosurgery Institute, Capital Medical University, Beijing, P.R. China
| | - Jingling Chang
- Dongzhimen Hospital, Beijing university of Chinese Medicine, Beijing, P.R. China
| | - Zhanjun Zhang
- State Key Laboratory of Cognitive Neuroscience and Learning & IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, P.R. China
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Lancaster C, Tabet N, Rusted J. The APOE paradox: do attentional control differences in mid-adulthood reflect risk of late-life cognitive decline. Neurobiol Aging 2016; 48:114-121. [PMID: 27661410 DOI: 10.1016/j.neurobiolaging.2016.08.015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 08/17/2016] [Accepted: 08/17/2016] [Indexed: 01/17/2023]
Abstract
Possession of an Apolipoprotein E (APOE) e4 allele is an established risk factor for Alzheimer's disease, whereas the less commonly studied e2 variant is premised to offer some protection. This research explores the purported deleterious-protective dichotomy of APOE variants on attentional control in mid-adulthood. Sixty-six volunteers, aged 45-55 years, completed 3 tasks that provided complementary measures of attentional control: prospective memory, sustained attention, and inhibition. Performance was compared between e2 carriers, e4 carriers, and e3 homozygotes (the population norm). Carriers of the e4 allele showed subtle disadvantages, compared with the e3 group, in accuracy of Stroop task and prospective memory performance. Contrary to expectations, e2 carriers showed performance disadvantages in sustained attention. The finding of detrimental effects in attentional control for both e4 and e2 complicates the current model that proposes opposing effects of these variants on later-life cognition. Future research is needed to understand how cognitive differences develop with increasing age, and the physiological mechanisms that underpin these changes.
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Affiliation(s)
- Claire Lancaster
- School of Psychology, University of Sussex, Brighton, East Sussex, UK
| | - Naji Tabet
- Brighton and Sussex Medical School, Institute of Postgraduate Medicine, Brighton, East Sussex, UK
| | - Jennifer Rusted
- School of Psychology, University of Sussex, Brighton, East Sussex, UK.
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Chang L, Douet V, Bloss C, Lee K, Pritchett A, Jernigan TL, Akshoomoff N, Murray SS, Frazier J, Kennedy DN, Amaral DG, Gruen J, Kaufmann WE, Casey BJ, Sowell E, Ernst T. Gray matter maturation and cognition in children with different APOE ε genotypes. Neurology 2016; 87:585-94. [PMID: 27412137 DOI: 10.1212/wnl.0000000000002939] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 03/28/2016] [Indexed: 01/15/2023] Open
Abstract
OBJECTIVE The aims of the current study were to determine whether children with the 6 different APOE ε genotypes show differences in gray matter maturation, particularly for those with ε4 and ε2 alleles, which are associated with poorer outcomes in many neurologic disorders. METHODS A total of 1,187 healthy children (aged 3-20 years, 52.1% boys, 47.9% girls) with acceptable data from the cross-sectional Pediatric Imaging Neurocognition and Genetics Study were evaluated for the effects of 6 APOE ε genotypes on macroscopic and microscopic cortical and subcortical gray matter structures (measured with 3-tesla MRI and FreeSurfer for automated morphometry) and on cognition (NIH Toolbox). RESULTS Among APOE ε4 carriers, age-related changes in brain structures and cognition varied depending on genotype, with the smallest hippocampi in ε2ε4 children, the lowest hippocampal fractional anisotropy in younger ε4ε4 children, the largest medial orbitofrontal cortical areas in ε3ε4 children, and age-dependent thinning of the entorhinal cortex in ε4ε4 children. Younger ε4ε4 children had the lowest scores on executive function and working memory, while younger ε2ε4 children performed worse on attention tasks. Larger parietal gyri in the younger ε2ε4 children, and thinner temporal and cingulate isthmus cortices or smaller hippocampi in the younger ε4ε4 children, predicted poorer performance on attention or working memory. CONCLUSIONS Our findings validated and extended prior smaller studies that showed altered brain development in APOE ε4-carrier children. The ε4ε4 and ε2ε4 genotypes may negatively influence brain development and brain aging at the extremes of age. Studying APOE ε polymorphisms in young children may provide the earliest indicators for individuals who might benefit from early interventions or preventive measures for future brain injuries and dementia.
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Affiliation(s)
- Linda Chang
- From the Department of Medicine (L.C., V.D., K.L., A.P., T.E.), John A. Burns School of Medicine, University of Hawaii and The Queen's Medical Center, Honolulu; Department of Psychiatry, School of Medicine (C.B.), Departments of Psychiatry and Cognitive Science (T.L.J., N.A.), and Department of Pathology (S.S.M.), University of California San Diego, La Jolla; Department of Psychiatry (J.F., D.N.K.), University of Massachusetts Medical School, Boston; Department of Psychiatry and Behavioral Sciences (D.G.A.), University of California, Davis; Departments of Pediatrics and Investigative Medicine (J.G.), Yale Child Health Research Center, Yale University School of Medicine, New Haven, CT; Boston Children's Hospital (W.E.K.), Harvard Medical School, Boston, MA; Sackler Institute for Developmental Psychobiology (B.J.C.), Weil Cornell Medical College, New York, NY; Department of Pediatrics (E.S.), University of Southern California, Los Angeles; and Children's Hospital (E.S.), Los Angeles, CA.
| | - Vanessa Douet
- From the Department of Medicine (L.C., V.D., K.L., A.P., T.E.), John A. Burns School of Medicine, University of Hawaii and The Queen's Medical Center, Honolulu; Department of Psychiatry, School of Medicine (C.B.), Departments of Psychiatry and Cognitive Science (T.L.J., N.A.), and Department of Pathology (S.S.M.), University of California San Diego, La Jolla; Department of Psychiatry (J.F., D.N.K.), University of Massachusetts Medical School, Boston; Department of Psychiatry and Behavioral Sciences (D.G.A.), University of California, Davis; Departments of Pediatrics and Investigative Medicine (J.G.), Yale Child Health Research Center, Yale University School of Medicine, New Haven, CT; Boston Children's Hospital (W.E.K.), Harvard Medical School, Boston, MA; Sackler Institute for Developmental Psychobiology (B.J.C.), Weil Cornell Medical College, New York, NY; Department of Pediatrics (E.S.), University of Southern California, Los Angeles; and Children's Hospital (E.S.), Los Angeles, CA
| | - Cinnamon Bloss
- From the Department of Medicine (L.C., V.D., K.L., A.P., T.E.), John A. Burns School of Medicine, University of Hawaii and The Queen's Medical Center, Honolulu; Department of Psychiatry, School of Medicine (C.B.), Departments of Psychiatry and Cognitive Science (T.L.J., N.A.), and Department of Pathology (S.S.M.), University of California San Diego, La Jolla; Department of Psychiatry (J.F., D.N.K.), University of Massachusetts Medical School, Boston; Department of Psychiatry and Behavioral Sciences (D.G.A.), University of California, Davis; Departments of Pediatrics and Investigative Medicine (J.G.), Yale Child Health Research Center, Yale University School of Medicine, New Haven, CT; Boston Children's Hospital (W.E.K.), Harvard Medical School, Boston, MA; Sackler Institute for Developmental Psychobiology (B.J.C.), Weil Cornell Medical College, New York, NY; Department of Pediatrics (E.S.), University of Southern California, Los Angeles; and Children's Hospital (E.S.), Los Angeles, CA
| | - Kristin Lee
- From the Department of Medicine (L.C., V.D., K.L., A.P., T.E.), John A. Burns School of Medicine, University of Hawaii and The Queen's Medical Center, Honolulu; Department of Psychiatry, School of Medicine (C.B.), Departments of Psychiatry and Cognitive Science (T.L.J., N.A.), and Department of Pathology (S.S.M.), University of California San Diego, La Jolla; Department of Psychiatry (J.F., D.N.K.), University of Massachusetts Medical School, Boston; Department of Psychiatry and Behavioral Sciences (D.G.A.), University of California, Davis; Departments of Pediatrics and Investigative Medicine (J.G.), Yale Child Health Research Center, Yale University School of Medicine, New Haven, CT; Boston Children's Hospital (W.E.K.), Harvard Medical School, Boston, MA; Sackler Institute for Developmental Psychobiology (B.J.C.), Weil Cornell Medical College, New York, NY; Department of Pediatrics (E.S.), University of Southern California, Los Angeles; and Children's Hospital (E.S.), Los Angeles, CA
| | - Alexandra Pritchett
- From the Department of Medicine (L.C., V.D., K.L., A.P., T.E.), John A. Burns School of Medicine, University of Hawaii and The Queen's Medical Center, Honolulu; Department of Psychiatry, School of Medicine (C.B.), Departments of Psychiatry and Cognitive Science (T.L.J., N.A.), and Department of Pathology (S.S.M.), University of California San Diego, La Jolla; Department of Psychiatry (J.F., D.N.K.), University of Massachusetts Medical School, Boston; Department of Psychiatry and Behavioral Sciences (D.G.A.), University of California, Davis; Departments of Pediatrics and Investigative Medicine (J.G.), Yale Child Health Research Center, Yale University School of Medicine, New Haven, CT; Boston Children's Hospital (W.E.K.), Harvard Medical School, Boston, MA; Sackler Institute for Developmental Psychobiology (B.J.C.), Weil Cornell Medical College, New York, NY; Department of Pediatrics (E.S.), University of Southern California, Los Angeles; and Children's Hospital (E.S.), Los Angeles, CA
| | - Terry L Jernigan
- From the Department of Medicine (L.C., V.D., K.L., A.P., T.E.), John A. Burns School of Medicine, University of Hawaii and The Queen's Medical Center, Honolulu; Department of Psychiatry, School of Medicine (C.B.), Departments of Psychiatry and Cognitive Science (T.L.J., N.A.), and Department of Pathology (S.S.M.), University of California San Diego, La Jolla; Department of Psychiatry (J.F., D.N.K.), University of Massachusetts Medical School, Boston; Department of Psychiatry and Behavioral Sciences (D.G.A.), University of California, Davis; Departments of Pediatrics and Investigative Medicine (J.G.), Yale Child Health Research Center, Yale University School of Medicine, New Haven, CT; Boston Children's Hospital (W.E.K.), Harvard Medical School, Boston, MA; Sackler Institute for Developmental Psychobiology (B.J.C.), Weil Cornell Medical College, New York, NY; Department of Pediatrics (E.S.), University of Southern California, Los Angeles; and Children's Hospital (E.S.), Los Angeles, CA
| | - Natacha Akshoomoff
- From the Department of Medicine (L.C., V.D., K.L., A.P., T.E.), John A. Burns School of Medicine, University of Hawaii and The Queen's Medical Center, Honolulu; Department of Psychiatry, School of Medicine (C.B.), Departments of Psychiatry and Cognitive Science (T.L.J., N.A.), and Department of Pathology (S.S.M.), University of California San Diego, La Jolla; Department of Psychiatry (J.F., D.N.K.), University of Massachusetts Medical School, Boston; Department of Psychiatry and Behavioral Sciences (D.G.A.), University of California, Davis; Departments of Pediatrics and Investigative Medicine (J.G.), Yale Child Health Research Center, Yale University School of Medicine, New Haven, CT; Boston Children's Hospital (W.E.K.), Harvard Medical School, Boston, MA; Sackler Institute for Developmental Psychobiology (B.J.C.), Weil Cornell Medical College, New York, NY; Department of Pediatrics (E.S.), University of Southern California, Los Angeles; and Children's Hospital (E.S.), Los Angeles, CA
| | - Sarah S Murray
- From the Department of Medicine (L.C., V.D., K.L., A.P., T.E.), John A. Burns School of Medicine, University of Hawaii and The Queen's Medical Center, Honolulu; Department of Psychiatry, School of Medicine (C.B.), Departments of Psychiatry and Cognitive Science (T.L.J., N.A.), and Department of Pathology (S.S.M.), University of California San Diego, La Jolla; Department of Psychiatry (J.F., D.N.K.), University of Massachusetts Medical School, Boston; Department of Psychiatry and Behavioral Sciences (D.G.A.), University of California, Davis; Departments of Pediatrics and Investigative Medicine (J.G.), Yale Child Health Research Center, Yale University School of Medicine, New Haven, CT; Boston Children's Hospital (W.E.K.), Harvard Medical School, Boston, MA; Sackler Institute for Developmental Psychobiology (B.J.C.), Weil Cornell Medical College, New York, NY; Department of Pediatrics (E.S.), University of Southern California, Los Angeles; and Children's Hospital (E.S.), Los Angeles, CA
| | - Jean Frazier
- From the Department of Medicine (L.C., V.D., K.L., A.P., T.E.), John A. Burns School of Medicine, University of Hawaii and The Queen's Medical Center, Honolulu; Department of Psychiatry, School of Medicine (C.B.), Departments of Psychiatry and Cognitive Science (T.L.J., N.A.), and Department of Pathology (S.S.M.), University of California San Diego, La Jolla; Department of Psychiatry (J.F., D.N.K.), University of Massachusetts Medical School, Boston; Department of Psychiatry and Behavioral Sciences (D.G.A.), University of California, Davis; Departments of Pediatrics and Investigative Medicine (J.G.), Yale Child Health Research Center, Yale University School of Medicine, New Haven, CT; Boston Children's Hospital (W.E.K.), Harvard Medical School, Boston, MA; Sackler Institute for Developmental Psychobiology (B.J.C.), Weil Cornell Medical College, New York, NY; Department of Pediatrics (E.S.), University of Southern California, Los Angeles; and Children's Hospital (E.S.), Los Angeles, CA
| | - David N Kennedy
- From the Department of Medicine (L.C., V.D., K.L., A.P., T.E.), John A. Burns School of Medicine, University of Hawaii and The Queen's Medical Center, Honolulu; Department of Psychiatry, School of Medicine (C.B.), Departments of Psychiatry and Cognitive Science (T.L.J., N.A.), and Department of Pathology (S.S.M.), University of California San Diego, La Jolla; Department of Psychiatry (J.F., D.N.K.), University of Massachusetts Medical School, Boston; Department of Psychiatry and Behavioral Sciences (D.G.A.), University of California, Davis; Departments of Pediatrics and Investigative Medicine (J.G.), Yale Child Health Research Center, Yale University School of Medicine, New Haven, CT; Boston Children's Hospital (W.E.K.), Harvard Medical School, Boston, MA; Sackler Institute for Developmental Psychobiology (B.J.C.), Weil Cornell Medical College, New York, NY; Department of Pediatrics (E.S.), University of Southern California, Los Angeles; and Children's Hospital (E.S.), Los Angeles, CA
| | - David G Amaral
- From the Department of Medicine (L.C., V.D., K.L., A.P., T.E.), John A. Burns School of Medicine, University of Hawaii and The Queen's Medical Center, Honolulu; Department of Psychiatry, School of Medicine (C.B.), Departments of Psychiatry and Cognitive Science (T.L.J., N.A.), and Department of Pathology (S.S.M.), University of California San Diego, La Jolla; Department of Psychiatry (J.F., D.N.K.), University of Massachusetts Medical School, Boston; Department of Psychiatry and Behavioral Sciences (D.G.A.), University of California, Davis; Departments of Pediatrics and Investigative Medicine (J.G.), Yale Child Health Research Center, Yale University School of Medicine, New Haven, CT; Boston Children's Hospital (W.E.K.), Harvard Medical School, Boston, MA; Sackler Institute for Developmental Psychobiology (B.J.C.), Weil Cornell Medical College, New York, NY; Department of Pediatrics (E.S.), University of Southern California, Los Angeles; and Children's Hospital (E.S.), Los Angeles, CA
| | - Jeffrey Gruen
- From the Department of Medicine (L.C., V.D., K.L., A.P., T.E.), John A. Burns School of Medicine, University of Hawaii and The Queen's Medical Center, Honolulu; Department of Psychiatry, School of Medicine (C.B.), Departments of Psychiatry and Cognitive Science (T.L.J., N.A.), and Department of Pathology (S.S.M.), University of California San Diego, La Jolla; Department of Psychiatry (J.F., D.N.K.), University of Massachusetts Medical School, Boston; Department of Psychiatry and Behavioral Sciences (D.G.A.), University of California, Davis; Departments of Pediatrics and Investigative Medicine (J.G.), Yale Child Health Research Center, Yale University School of Medicine, New Haven, CT; Boston Children's Hospital (W.E.K.), Harvard Medical School, Boston, MA; Sackler Institute for Developmental Psychobiology (B.J.C.), Weil Cornell Medical College, New York, NY; Department of Pediatrics (E.S.), University of Southern California, Los Angeles; and Children's Hospital (E.S.), Los Angeles, CA
| | - Walter E Kaufmann
- From the Department of Medicine (L.C., V.D., K.L., A.P., T.E.), John A. Burns School of Medicine, University of Hawaii and The Queen's Medical Center, Honolulu; Department of Psychiatry, School of Medicine (C.B.), Departments of Psychiatry and Cognitive Science (T.L.J., N.A.), and Department of Pathology (S.S.M.), University of California San Diego, La Jolla; Department of Psychiatry (J.F., D.N.K.), University of Massachusetts Medical School, Boston; Department of Psychiatry and Behavioral Sciences (D.G.A.), University of California, Davis; Departments of Pediatrics and Investigative Medicine (J.G.), Yale Child Health Research Center, Yale University School of Medicine, New Haven, CT; Boston Children's Hospital (W.E.K.), Harvard Medical School, Boston, MA; Sackler Institute for Developmental Psychobiology (B.J.C.), Weil Cornell Medical College, New York, NY; Department of Pediatrics (E.S.), University of Southern California, Los Angeles; and Children's Hospital (E.S.), Los Angeles, CA
| | - B J Casey
- From the Department of Medicine (L.C., V.D., K.L., A.P., T.E.), John A. Burns School of Medicine, University of Hawaii and The Queen's Medical Center, Honolulu; Department of Psychiatry, School of Medicine (C.B.), Departments of Psychiatry and Cognitive Science (T.L.J., N.A.), and Department of Pathology (S.S.M.), University of California San Diego, La Jolla; Department of Psychiatry (J.F., D.N.K.), University of Massachusetts Medical School, Boston; Department of Psychiatry and Behavioral Sciences (D.G.A.), University of California, Davis; Departments of Pediatrics and Investigative Medicine (J.G.), Yale Child Health Research Center, Yale University School of Medicine, New Haven, CT; Boston Children's Hospital (W.E.K.), Harvard Medical School, Boston, MA; Sackler Institute for Developmental Psychobiology (B.J.C.), Weil Cornell Medical College, New York, NY; Department of Pediatrics (E.S.), University of Southern California, Los Angeles; and Children's Hospital (E.S.), Los Angeles, CA
| | - Elizabeth Sowell
- From the Department of Medicine (L.C., V.D., K.L., A.P., T.E.), John A. Burns School of Medicine, University of Hawaii and The Queen's Medical Center, Honolulu; Department of Psychiatry, School of Medicine (C.B.), Departments of Psychiatry and Cognitive Science (T.L.J., N.A.), and Department of Pathology (S.S.M.), University of California San Diego, La Jolla; Department of Psychiatry (J.F., D.N.K.), University of Massachusetts Medical School, Boston; Department of Psychiatry and Behavioral Sciences (D.G.A.), University of California, Davis; Departments of Pediatrics and Investigative Medicine (J.G.), Yale Child Health Research Center, Yale University School of Medicine, New Haven, CT; Boston Children's Hospital (W.E.K.), Harvard Medical School, Boston, MA; Sackler Institute for Developmental Psychobiology (B.J.C.), Weil Cornell Medical College, New York, NY; Department of Pediatrics (E.S.), University of Southern California, Los Angeles; and Children's Hospital (E.S.), Los Angeles, CA
| | - Thomas Ernst
- From the Department of Medicine (L.C., V.D., K.L., A.P., T.E.), John A. Burns School of Medicine, University of Hawaii and The Queen's Medical Center, Honolulu; Department of Psychiatry, School of Medicine (C.B.), Departments of Psychiatry and Cognitive Science (T.L.J., N.A.), and Department of Pathology (S.S.M.), University of California San Diego, La Jolla; Department of Psychiatry (J.F., D.N.K.), University of Massachusetts Medical School, Boston; Department of Psychiatry and Behavioral Sciences (D.G.A.), University of California, Davis; Departments of Pediatrics and Investigative Medicine (J.G.), Yale Child Health Research Center, Yale University School of Medicine, New Haven, CT; Boston Children's Hospital (W.E.K.), Harvard Medical School, Boston, MA; Sackler Institute for Developmental Psychobiology (B.J.C.), Weil Cornell Medical College, New York, NY; Department of Pediatrics (E.S.), University of Southern California, Los Angeles; and Children's Hospital (E.S.), Los Angeles, CA
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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] [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.
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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
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Racine AM, Koscik RL, Berman SE, Nicholas CR, Clark LR, Okonkwo OC, Rowley HA, Asthana S, Bendlin BB, Blennow K, Zetterberg H, Gleason CE, Carlsson CM, Johnson SC. Biomarker clusters are differentially associated with longitudinal cognitive decline in late midlife. Brain 2016; 139:2261-74. [PMID: 27324877 DOI: 10.1093/brain/aww142] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 05/05/2016] [Indexed: 11/12/2022] Open
Abstract
The ability to detect preclinical Alzheimer's disease is of great importance, as this stage of the Alzheimer's continuum is believed to provide a key window for intervention and prevention. As Alzheimer's disease is characterized by multiple pathological changes, a biomarker panel reflecting co-occurring pathology will likely be most useful for early detection. Towards this end, 175 late middle-aged participants (mean age 55.9 ± 5.7 years at first cognitive assessment, 70% female) were recruited from two longitudinally followed cohorts to undergo magnetic resonance imaging and lumbar puncture. Cluster analysis was used to group individuals based on biomarkers of amyloid pathology (cerebrospinal fluid amyloid-β42/amyloid-β40 assay levels), magnetic resonance imaging-derived measures of neurodegeneration/atrophy (cerebrospinal fluid-to-brain volume ratio, and hippocampal volume), neurofibrillary tangles (cerebrospinal fluid phosphorylated tau181 assay levels), and a brain-based marker of vascular risk (total white matter hyperintensity lesion volume). Four biomarker clusters emerged consistent with preclinical features of (i) Alzheimer's disease; (ii) mixed Alzheimer's disease and vascular aetiology; (iii) suspected non-Alzheimer's disease aetiology; and (iv) healthy ageing. Cognitive decline was then analysed between clusters using longitudinal assessments of episodic memory, semantic memory, executive function, and global cognitive function with linear mixed effects modelling. Cluster 1 exhibited a higher intercept and greater rates of decline on tests of episodic memory. Cluster 2 had a lower intercept on a test of semantic memory and both Cluster 2 and Cluster 3 had steeper rates of decline on a test of global cognition. Additional analyses on Cluster 3, which had the smallest hippocampal volume, suggest that its biomarker profile is more likely due to hippocampal vulnerability and not to detectable specific volume loss exceeding the rate of normal ageing. Our results demonstrate that pathology, as indicated by biomarkers, in a preclinical timeframe is related to patterns of longitudinal cognitive decline. Such biomarker patterns may be useful for identifying at-risk populations to recruit for clinical trials.
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Affiliation(s)
- Annie M Racine
- 1 Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA 2 Institute on Aging, University of Wisconsin-Madison, USA, Madison, WI 53706, USA 3 Neuroscience and Public Policy Program, University of Wisconsin-Madison, USA, Madison, WI 53705, USA
| | - Rebecca L Koscik
- 4 Wisconsin Alzheimer's Institute, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA
| | - Sara E Berman
- 1 Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA
| | - Christopher R Nicholas
- 1 Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA 5 Geriatric Research Education and Clinical Center, Wm. S. Middleton Veterans Hospital, USA, Madison WI 53705, USA
| | - Lindsay R Clark
- 1 Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA 4 Wisconsin Alzheimer's Institute, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA 5 Geriatric Research Education and Clinical Center, Wm. S. Middleton Veterans Hospital, USA, Madison WI 53705, USA
| | - Ozioma C Okonkwo
- 1 Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA 4 Wisconsin Alzheimer's Institute, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA
| | - Howard A Rowley
- 1 Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA 6 Department of Radiology, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA
| | - Sanjay Asthana
- 1 Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA 5 Geriatric Research Education and Clinical Center, Wm. S. Middleton Veterans Hospital, USA, Madison WI 53705, USA
| | - Barbara B Bendlin
- 1 Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA 4 Wisconsin Alzheimer's Institute, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA
| | - Kaj Blennow
- 7 Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden 8 Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Henrik Zetterberg
- 7 Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden 8 Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden 9 Institute of Neurology, University College London, London, UK
| | - Carey E Gleason
- 1 Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA 5 Geriatric Research Education and Clinical Center, Wm. S. Middleton Veterans Hospital, USA, Madison WI 53705, USA
| | - Cynthia M Carlsson
- 1 Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA 4 Wisconsin Alzheimer's Institute, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA 5 Geriatric Research Education and Clinical Center, Wm. S. Middleton Veterans Hospital, USA, Madison WI 53705, USA
| | - Sterling C Johnson
- 1 Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA 4 Wisconsin Alzheimer's Institute, University of Wisconsin School of Medicine and Public Health, USA, Madison, WI 53705, USA 5 Geriatric Research Education and Clinical Center, Wm. S. Middleton Veterans Hospital, USA, Madison WI 53705, USA 10 Waisman Laboratory for Brain Imaging and Behavior, University of Wisconsin-Madison, USA, Madison, WI 53705, USA
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Luo X, Qiu T, Xu X, Huang P, Gu Q, Shen Z, Yu X, Jia Y, Guan X, Song R, Zhang M. Decreased Inter-Hemispheric Functional Connectivity in Cognitively Intact Elderly APOE ɛ4 Carriers: A Preliminary Study. J Alzheimers Dis 2016; 50:1137-48. [DOI: 10.3233/jad-150989] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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47
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Kulminski AM, Arbeev KG, Culminskaya I, Ukraintseva SV, Stallard E, Province MA, Yashin AI. Trade-offs in the effects of the apolipoprotein E polymorphism on risks of diseases of the heart, cancer, and neurodegenerative disorders: insights on mechanisms from the Long Life Family Study. Rejuvenation Res 2016; 18:128-35. [PMID: 25482294 DOI: 10.1089/rej.2014.1616] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The lack of evolutionary established mechanisms linking genes to age-related traits makes the problem of genetic susceptibility to health span inherently complex. One complicating factor is genetic trade-off. Here we focused on long-living participants of the Long Life Family Study (LLFS), their offspring, and spouses to: (1) Elucidate whether trade-offs in the effect of the apolipoprotein E e4 allele documented in the Framingham Heart Study (FHS) are a more general phenomenon, and (2) explore potential mechanisms generating age- and gender-specific trade-offs in the effect of the e4 allele on cancer, diseases of the heart, and neurodegenerative disorders assessed retrospectively in the LLFS populations. The e4 allele can diminish risks of cancer and diseases of the heart and confer risks of diseases of the heart in a sex-, age-, and LLFS-population-specific manner. A protective effect against cancer is seen in older long-living men and, potentially, their sons (>75 years, relative risk [RR]>75=0.48, p=0.086), which resembles our findings in the FHS. The protective effect against diseases of the heart is limited to long-living older men (RR>76=0.50, p=0.016), as well. A detrimental effect against diseases of the heart is characteristic for a normal LLFS population of male spouses and is specific for myocardial infarction (RR=3.07, p=2.1×10(-3)). These trade-offs are likely associated with two inherently different mechanisms, including disease-specific (detrimental; characteristic for a normal male population) and systemic, aging-related (protective; characteristic for older long-living men) mechanisms. The e4 allele confers risks of neurological disorders in men and women (RR=1.98, p=0.046). The results highlight the complex role of the e4 allele in genetic susceptibility to health span.
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48
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Rusted J, Carare RO. Are the effects of APOE ϵ4 on cognitive function in nonclinical populations age- and gender-dependent? Neurodegener Dis Manag 2016; 5:37-48. [PMID: 25711453 DOI: 10.2217/nmt.14.43] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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.
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49
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Stening E, Persson J, Eriksson E, Wahlund LO, Zetterberg H, Söderlund H. Apolipoprotein E ϵ4 is positively related to spatial performance but unrelated to hippocampal volume in healthy young adults. Behav Brain Res 2015; 299:11-8. [PMID: 26581118 DOI: 10.1016/j.bbr.2015.11.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 10/17/2015] [Accepted: 11/06/2015] [Indexed: 12/30/2022]
Abstract
The apolipoprotein E (APOE) ϵ4 allele is known to be a major genetic risk factor for Alzheimer's disease (AD). It has been linked to especially episodic memory decline and hippocampal atrophy in both healthy and demented elderly populations. In young adults, ϵ4 carriers have shown better performance in episodic memory compared to non-carriers. Spatial memory, however, has not been thoroughly assessed in relation to APOE in spite of its dependence on the hippocampus. In this study, we assessed the effect of APOE genotype on a variety of spatial and episodic memory tasks as well as hippocampal volume assessed through manual tracing in a sample of young adults (N=123). We also assessed whether potential effects were modulated by sex. The presence of one or more ϵ4 alleles had positive effects on spatial function and memory and object location memory, but no effect on word recognition. Men were superior to women in spatial function and memory but there were no sex differences in the other tasks. In spite of APOE ϵ4 carriers having superior performance in several memory tasks, no difference was found as a function of APOE genotype in hippocampal volume. To our knowledge, this study is the first to show that APOE ϵ4 has a positive effect on spatial ability in young adults.
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Affiliation(s)
- Eva Stening
- Department of Psychology, Uppsala University, Uppsala, Sweden.
| | - Jonas Persson
- Department of Psychology, Uppsala University, Uppsala, Sweden
| | - Elias Eriksson
- Department of Pharmacology, Institute of Physiology and Neuroscience, Sahlgrenska Academy, University of Gothenburg, Sweden
| | - Lars-Olof Wahlund
- Department of Neurobiology, Care Sciences and Society, Division of Clinical Geriatrics, Karolinska Institute, Stockholm, Sweden
| | - Henrik Zetterberg
- Clinical Neurochemistry Laboratory, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden; Department of Molecular Neuroscience, UCL Institute of Neurology, Queen Square, London, UK
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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] [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.
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