Functional neuroanatomical associations of working memory in early-onset Alzheimer's disease.

PubMed

Kobylecki, Christopher; Haense, Cathleen; Harris, Jennifer M; Stopford, Cheryl L; Segobin, Shailendra H; Jones, Matthew; Richardson, Anna M T; Gerhard, Alexander; Anton-Rodriguez, José; Thompson, Jennifer C; Herholz, Karl; Snowden, Julie S

2018-01-01

To characterize metabolic correlates of working memory impairment in clinically defined subtypes of early-onset Alzheimer's disease. Established models of working memory suggest a key role for frontal lobe function, yet the association in Alzheimer's disease between working memory impairment and visuospatial and language symptoms suggests that temporoparietal neocortical dysfunction may be responsible. Twenty-four patients with predominantly early-onset Alzheimer's disease were clinically classified into groups with predominantly amnestic, multidomain or visual deficits. Patients underwent neuropsychological evaluation focused on the domains of episodic and working memory, T1-weighted magnetic resonance imaging and brain fluorodeoxyglucose positron emission tomography. Fluorodeoxyglucose positron emission tomography data were analysed by using a region-of-interest approach. Patients with multidomain and visual presentations performed more poorly on tests of working memory compared with amnestic Alzheimer's disease. Working memory performance correlated with glucose metabolism in left-sided temporoparietal, but not frontal neocortex. Carriers of the apolipoprotein E4 gene showed poorer episodic memory and better working memory performance compared with noncarriers. Our findings support the hypothesis that working memory changes in early-onset Alzheimer's disease are related to temporoparietal rather than frontal hypometabolism and show dissociation from episodic memory performance. They further support the concept of subtypes of Alzheimer's disease with distinct cognitive profiles due to prominent neocortical dysfunction early in the disease course. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Polygenic risk score in postmortem diagnosed sporadic early-onset Alzheimer's disease.

PubMed

Chaudhury, Sultan; Patel, Tulsi; Barber, Imelda S; Guetta-Baranes, Tamar; Brookes, Keeley J; Chappell, Sally; Turton, James; Guerreiro, Rita; Bras, Jose; Hernandez, Dena; Singleton, Andrew; Hardy, John; Mann, David; Morgan, Kevin

2018-02-01

Sporadic early-onset Alzheimer's disease (sEOAD) exhibits the symptoms of late-onset Alzheimer's disease but lacks the familial aspect of the early-onset familial form. The genetics of Alzheimer's disease (AD) identifies APOEε4 to be the greatest risk factor; however, it is a complex disease involving both environmental risk factors and multiple genetic loci. Polygenic risk scores (PRSs) accumulate the total risk of a phenotype in an individual based on variants present in their genome. We determined whether sEOAD cases had a higher PRS compared to controls. A cohort of sEOAD cases was genotyped on the NeuroX array, and PRSs were generated using PRSice. The target data set consisted of 408 sEOAD cases and 436 controls. The base data set was collated by the International Genomics of Alzheimer's Project consortium, with association data from 17,008 late-onset Alzheimer's disease cases and 37,154 controls, which can be used for identifying sEOAD cases due to having shared phenotype. PRSs were generated using all common single nucleotide polymorphisms between the base and target data set, PRS were also generated using only single nucleotide polymorphisms within a 500 kb region surrounding the APOE gene. Sex and number of APOE ε2 or ε4 alleles were used as variables for logistic regression and combined with PRS. The results show that PRS is higher on average in sEOAD cases than controls, although there is still overlap among the whole cohort. Predictive ability of identifying cases and controls using PRSice was calculated with 72.9% accuracy, greater than the APOE locus alone (65.2%). Predictive ability was further improved with logistic regression, identifying cases and controls with 75.5% accuracy. Copyright © 2017 Elsevier Inc. All rights reserved.

Incidence of cognitively defined late-onset Alzheimer's dementia subgroups from a prospective cohort study.

PubMed

Crane, Paul K; Trittschuh, Emily; Mukherjee, Shubhabrata; Saykin, Andrew J; Sanders, R Elizabeth; Larson, Eric B; McCurry, Susan M; McCormick, Wayne; Bowen, James D; Grabowski, Thomas; Moore, Mackenzie; Bauman, Julianna; Gross, Alden L; Keene, C Dirk; Bird, Thomas D; Gibbons, Laura E; Mez, Jesse

2017-12-01

There may be biologically relevant heterogeneity within typical late-onset Alzheimer's dementia. We analyzed cognitive data from people with incident late-onset Alzheimer's dementia from a prospective cohort study. We determined individual averages across memory, visuospatial functioning, language, and executive functioning. We identified domains with substantial impairments relative to that average. We compared demographic, neuropathology, and genetic findings across groups defined by relative impairments. During 32,286 person-years of follow-up, 869 people developed Alzheimer's dementia. There were 393 (48%) with no domain with substantial relative impairments. Some participants had isolated relative impairments in memory (148, 18%), visuospatial functioning (117, 14%), language (71, 9%), and executive functioning (66, 8%). The group with isolated relative memory impairments had higher proportions with ≥ APOE ε4 allele, more extensive Alzheimer's-related neuropathology, and higher proportions with other Alzheimer's dementia genetic risk variants. A cognitive subgrouping strategy may identify biologically distinct subsets of people with Alzheimer's dementia. Copyright © 2017 the Alzheimer's Association. All rights reserved.

Chromosome 14 and late-onset familial alzheimer disease (FAD)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schellenberg, G.D.; Anderson, L.; Nemens, E.

1993-09-01

Familial Alzheimer disease (FAD) is genetically heterogeneous. Two loci responsible for early-onset FAD have been identified: the amyloid precursor protein gene on chromosome 21 and the as-yet-unidentified locus on chromosome 14. The genetics of late-onset FAD is unresolved. Maximum-likelihood, affected-pedigree-member (APM), and sib-pair analysis were used, in 49 families with a mean age at onset [>=]60 years, to determine whether the chromosome 14 locus is responsible for late-onset FAD. The markers used were D14S53, D14S43, and D14S52. The LOD score method was used to test for linkage of late-onset FAD to the chromosome 14 markers, under three different models: age-dependentmore » penetrance, an affected-only analysis, and age-dependent penetrance with allowance for possible age-dependent sporadic cases. No evidence for linkage was obtained under any of these conditions for the late-onset kindreds, and strong evidence against linkage (LOD score [>=]2.0) to this region was obtained. Heterogeneity tests of the LOD score results for the combined group of families (early onset, Volga Germans, and late onset) favored the hypothesis of linkage to chromosome 14 with genetic heterogeneity. The positive results are primarily from early-onset families. APM analysis gave significant evidence for linkage of D14S43 and D14S52 to FAD in early-onset kindreds (P<.02). No evidence for linkage was found for the entire late-onset family group. Significant evidence for linkage to D14S52, however, was found for a subgroup of families of intermediate age at onset (mean age at onset [>=]60 years and <70 years). These results indicate that the chromosome 14 locus is not responsible for Alzheimer disease in most late-onset FAD kindreds but could play a role in a subset of these kindreds. 37 refs., 1 fig., 6 tabs.« less

Bilingualism as a strategy to delay the onset of Alzheimer's disease.

PubMed

Klimova, Blanka; Valis, Martin; Kuca, Kamil

2017-01-01

The purpose of this study is to explore original studies which provide evidence about the effects of bilingualism on the delay of the onset of dementia, specifically Alzheimer's disease (AD). A literature review was conducted in the world's acknowledged databases: Web of Science, Scopus, and MEDLINE. Altogether, 14 original studies focusing on the research topic were detected. These included six prospective cohort studies and eight retrospective studies. Both types of studies suggest different conclusions. The findings from the prospective cohort studies state that there is no association between bilingualism and the delay of the onset of AD, while the retrospective studies claim the opposite. Despite the negative results of the prospective cohort studies, more research should be conducted on bilingualism and its impact on the delay of the onset of AD, since the brain studies have brought positive findings as far as the enhancement of cognitive reserve is concerned.

New cardiovascular targets to prevent late onset Alzheimer disease.

PubMed

Claassen, Jurgen A H R

2015-09-15

The prevalence of dementia rises to between 20% and 40% with advancing age. The dominant cause of dementia in approximately 70% of these patients is Alzheimer disease. There is no effective disease-modifying pharmaceutical treatment for this neurodegenerative disease. A wide range of Alzheimer drugs that appeared effective in animal models have recently failed to show clinical benefit in patients. However, hopeful news has emerged from recent studies that suggest that therapeutic strategies aimed at reducing cardiovascular disease may also reduce the prevalence of dementia due to Alzheimer disease. This review summarizes the evidence for this link between cardiovascular disease and late onset Alzheimer dementia. Only evidence from human research is considered here. Longitudinal studies show an association between high blood pressure and pathological accumulation of the protein amyloid-beta42, and an even stronger association between vascular stiffness and amyloid accumulation, in elderly subjects. Amyloid-beta42 accumulation is considered to be an early marker of Alzheimer disease, and increases the risk of subsequent cognitive decline and development of dementia. These observations could provide an explanation for recent observations of reduced dementia prevalence associated with improved cardiovascular care. Copyright © 2015 Elsevier B.V. All rights reserved.

Phenotypic similarities between late-onset autosomal dominant and sporadic Alzheimer disease: A single-family case-control study

PubMed Central

Day, Gregory S; Musiek, Erik S; Roe, Catherine M; Norton, Joanne; Goate, Alison M; Cruchaga, Carlos; Cairns, Nigel J; Morris, John C

2016-01-01

Importance The “amyloid hypothesis” posits that disrupted amyloid-beta (Aβ) homeostasis initiates the pathological process resulting in Alzheimer disease (AD). Autosomal dominant Alzheimer disease (ADAD) has an early symptomatic onset and is caused by single gene mutations that result in overproduction of Aβ42. To the extent that “sporadic” late-onset Alzheimer disease (LOAD) also results from dysregulated Aβ42, the clinical phenotypes of ADAD and LOAD should be similar when controlling for the effects of age. Objective To use a family with late-onset ADAD caused by a presenilin 1 (PSEN1) mutation to mitigate the potential confound of age when comparing ADAD and LOAD. Design Case-control study of a family with late-onset ADAD and individuals with histopathologically-proven LOAD. Setting The Knight Alzheimer Disease Research Center, Washington University, St Louis, and other National Institutes of Aging-funded Alzheimer Disease Centers in the United States. Participants Ten PSEN1 A79V mutation carriers from multiple generations of a family with late-onset ADAD (median age-at-onset, 75.0 [63–77] years) and 12 noncarrier family members, followed at the Knight Alzheimer Disease Research Center (1985–2015); and 1115 individuals with neuropathologically confirmed LOAD (median age-at-onset, 74.0 [60–101] years) from the National Alzheimer Coordinating Center database (09/2005-12/14). Main Outcome and Measure Planned comparison of clinical characteristics between cohorts, including age at symptomatic onset, associated symptoms and signs, rates of progression, and disease duration. Results Seven (70%) mutation carriers developed AD dementia, while three are yet asymptomatic in their 7th and 8th decades of life. No differences were observed between mutation carriers and individuals with LOAD concerning age at symptomatic onset, presenting symptoms and duration, and rate of progression of dementia. Early emergence of comorbid hallucinations and delusions were

Voice Onset Time Production in Speakers with Alzheimer's Disease

ERIC Educational Resources Information Center

Baker, Julie; Ryalls, Jack; Brice, Alejandro; Whiteside, Janet

2007-01-01

In the present study, voice onset time (VOT) measurements were compared between a group of individuals with moderate Alzheimer's disease (AD) and a group of healthy age- and gender-matched peers. Participants read a list of consonant-vowel-consonant (CVC) words, which included the six stop consonants. The VOT measurements were made from…

Emotional Prosody Perception and Production in Dementia of the Alzheimer's Type

ERIC Educational Resources Information Center

Horley, Kaye; Reid, Amanda; Burnham, Denis

2010-01-01

Purpose: In this study, the authors investigated emotional prosody in patients with moderate Dementia of the Alzheimer's type (DAT) With Late Onset. It was expected that both expression and reception of prosody would be impaired relative to age-matched controls. Method: Twenty DAT and 20 control participants engaged in 2 expressive and 2 receptive…

The amyloid precursor protein locus and very-late-onset Alzheimer disease.

PubMed

Olson, J M; Goddard, K A; Dudek, D M

2001-10-01

Although mutations in the amyloid-beta precursor protein (APP) gene are known to confer high risk of Alzheimer disease (AD) to a small percentage of families in which it has early onset, convincing evidence of a major role for the APP locus in late-onset AD has not been forthcoming. In this report, we have used a covariate-based affected-sib-pair linkage method to analyze the chromosome 21 clinical and genetic data obtained on affected sibships by the National Institute of Mental Health Alzheimer Disease Genetics Initiative. The baseline model (without covariates) gave a LOD score of 0.02, which increases to 1.43 when covariates representing the additive effects of E2 and E4 are added. Larger increases in LOD scores were found when age at last examination/death (LOD score 5.54; P=.000002) or age at onset plus disease duration (LOD score 5.63; P=.000006) were included in the linkage model. We conclude that the APP locus may predispose to AD in the very elderly.

Difference in imaging biomarkers of neurodegeneration between early and late-onset amnestic Alzheimer's disease.

PubMed

Aziz, Anne-Laure; Giusiano, Bernard; Joubert, Sven; Duprat, Lauréline; Didic, Mira; Gueriot, Claude; Koric, Lejla; Boucraut, José; Felician, Olivier; Ranjeva, Jean-Philippe; Guedj, Eric; Ceccaldi, Mathieu

2017-06-01

Neuroimaging biomarkers differ between patients with early-onset Alzheimer's disease (EOAD) and late-onset Alzheimer's disease (LOAD). Whether these changes reflect cognitive heterogeneity or differences in disease severity is still unknown. This study aimed at investigating changes in neuroimaging biomarkers, according to the age of onset of the disease, in mild amnestic Alzheimer's disease patients with positive amyloid biomarkers in cerebrospinal fluid. Both patient groups were impaired on tasks assessing verbal and visual recognition memory. EOAD patients showed greater executive and linguistic deficits, while LOAD patients showed greater semantic memory impairment. In EOAD and LOAD, hypometabolism involved the bilateral temporoparietal junction and the posterior cingulate cortex. In EOAD, atrophy was widespread, including frontotemporoparietal areas, whereas it was limited to temporal regions in LOAD. Atrophic volumes were greater in EOAD than in LOAD. Hypometabolic volumes were similar in the 2 groups. Greater extent of atrophy in EOAD, despite similar extent of hypometabolism, could reflect different underlying pathophysiological processes, different glucose-based compensatory mechanisms or distinct level of premorbid atrophic lesions. Copyright © 2017 Elsevier Inc. All rights reserved.

The APOE locus advances disease progression in late onset familial Alzheimer`s disease but is not causative

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crawford, F.; Bennett, C.; Osborne, A.

1994-09-01

An association has been observed in several independent data sets between late onset Alzheimer`s disease (AD) and the APOE locus on chromosomes 19. We have examined the genotype in family history positive (FHP) and family history negative (FHN) cases and find a distortion of the APOE allele frequencies in accord with previous studies. However, when we examined the allele distribution of the at-risk siblings of the FHP group we found an excess of the {epsilon}4 allele which also differs significantly from historic controls but not from the affected siblings. The age distribution of the affected and unaffected siblings was similar,more » suggesting that the allelic frequency distortion in the unaffected siblings was not due to their being below the mean age of onset. Lod score linkage analysis, with age dependent onset and nonstringent specification of the genetic parameters, did not suggest linkage to the APOE locus. Furthermore, an analysis of variance of the age of disease-free survival suggested that APOE genotype contributes a small fraction of the total variance, indicating that the APOE locus is a poor predictor of disease-free survival time within late onset families. We suggest that the APOE locus enhances the rate of progression of the disease in otherwise predisposed individuals and that variation at this locus is not able in and of itself to cause this disease.« less

Clinical features of early onset, familial Alzheimer`s disease linked to chromosome 14

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mullan, M.; Bennett, C.; Figueredo, C.

1995-02-27

Early onset familial Alzheimer`s disease (AD) has an autosomal dominant mode of inheritance. Two genes are responsible for the majority of cases of this subtype of AD. Mutations in the {beta}-amyloid precursor protein ({beta}APP) gene on chromosome 21 have been shown to completely cosegregate with the disease. We and others have previously described the clinical features of families with {beta}APP mutations at the codon 717 locus in an attempt to define the phenotype associated with a valine to isoleucine (Val {r_arrow} Ile) or a valine to glycine (Val {r_arrow} Gly) change. More recently, a second locus for very early onsetmore » disease has been localized to chromosome 14. The results of linkage studies in some families suggesting linkage to both chromosomes have been explained by the suggestion of a second (centromeric) locus on chromosome 21. Here we report the clinical features and genetic analysis of a British pedigree (F74) with early onset AD in which neither the {beta}APP locus nor any other chromosome 21 locus segregates with the disease, but in which good evidence is seen for linkage on the long arm of chromosome 14. In particular we report marker data suggesting that the chromosome 14 disease locus is close to D14S43 and D14S77. Given the likelihood that F74 represents a chromosome 14 linked family, we describe the clinical features and make a limited clinical comparison with the {beta}APP717 Val {r_arrow} Ile and {beta}APP717 Val {r_arrow} Gly encoded families that have been previously described. We conclude that although several previously reported clinical features occur to excess in early onset familial AD, no single clinical feature demarcates either the chromosome 14 or {beta}APP codon 717 mutated families except mean age of onset. 52 refs., 2 figs., 5 tabs.« less

Dermatoglyphic patterns in dementia of the Alzheimer type: a case-control study.

PubMed

Berr, C; Okra-Podrabinek, N; Feteanu, D; Taurand, S; Hervy, M P; Forette, F; Piette, F; Sebag-Lanoe, R; Alperovitch, A

1992-10-01

The aim was to compare digital and palmar dermatoglyphics in subjects with dementia of Alzheimer type and in mentally healthy elderly controls. This design was a case-control study. The study was carried out in geriatric units and retirement communities in the Paris area. Cases were women with clinically diagnosed Alzheimer type dementia according to DSM III-R criteria (n = 82), mainly with late onset of the disease. Controls were women aged 85 years or older without cognitive deterioration (n = 76). Finger and palm prints obtained from both hands by the classical ink method were examined. Fingerprints were classified into four types of figures. On palms, palmar flexion creases, palmar axial triradii, true patterns of the hypothenar area, and main line terminations were described. Examinations were performed by two examiners blind to the subjects's diagnostic category. For the different patterns studied, no major differences between dementia patients and elderly controls were found. Nor was there evidence of high frequencies of features commonly observed in Down's syndrome (trisomy 21), which have previously, though sporadically, been reported. On one of the largest samples of Alzheimer dementia patients studied, and with evaluation blind to diagnosis, no evidence has been found that particular dermatoglyphic patterns occur like those observed in Down's syndrome, a disease which is related to dementia of the Alzheimer type.

Dermatoglyphic patterns in dementia of the Alzheimer type: a case-control study.

PubMed Central

Berr, C; Okra-Podrabinek, N; Feteanu, D; Taurand, S; Hervy, M P; Forette, F; Piette, F; Sebag-Lanoe, R; Alperovitch, A

1992-01-01

STUDY OBJECTIVE--The aim was to compare digital and palmar dermatoglyphics in subjects with dementia of Alzheimer type and in mentally healthy elderly controls. DESIGN--This design was a case-control study. SETTING--The study was carried out in geriatric units and retirement communities in the Paris area. PARTICIPANTS--Cases were women with clinically diagnosed Alzheimer type dementia according to DSM III-R criteria (n = 82), mainly with late onset of the disease. Controls were women aged 85 years or older without cognitive deterioration (n = 76). MEASUREMENTS AND MAIN RESULTS--Finger and palm prints obtained from both hands by the classical ink method were examined. Fingerprints were classified into four types of figures. On palms, palmar flexion creases, palmar axial triradii, true patterns of the hypothenar area, and main line terminations were described. Examinations were performed by two examiners blind to the subjects's diagnostic category. For the different patterns studied, no major differences between dementia patients and elderly controls were found. Nor was there evidence of high frequencies of features commonly observed in Down's syndrome (trisomy 21), which have previously, though sporadically, been reported. CONCLUSIONS--On one of the largest samples of Alzheimer dementia patients studied, and with evaluation blind to diagnosis, no evidence has been found that particular dermatoglyphic patterns occur like those observed in Down's syndrome, a disease which is related to dementia of the Alzheimer type. PMID:1479321

LONGITUDINAL FOLLOW-UP OF LATE-ONSET ALZHEIMER DISEASE FAMILIES

PubMed Central

Carney, R.M.; Slifer, M.A.; Lin, P.I.; Gaskell, P. C.; Scott, W. K.; Potocky, C.F.; Hulette, C. M.; Welsh-Bohmer, K. A.; Schmechel, D. E.; Vance, J.M.; Pericak-Vance, M. A.

2009-01-01

Historically, data for genetic studies are collected at one time point. However, for diseases with late onset or with complex phenotypes, such as Alzheimer disease (AD), restricting diagnosis to a single ascertainment contact may not be sufficient. Affection status may change over time, and some initial diagnoses may be inconclusive. Follow-up provides the opportunity to resolve these complications. However, to date, previous studies have not formally demonstrated that longitudinally re-contacting families is practical or productive. To update data initially collected for linkage analysis of late-onset Alzheimer disease (LOAD), we successfully re-contacted 63 of 81 (78%) multiplex families (two to 17 years after ascertainment). Clinical status changed for 73 of the 230 (32%) non-affected participants. Additionally, expanded family history identified 20 additional affected individuals to supplement the data set. Furthermore, fostering ongoing relationships with participating families helped recruit 101 affected participants into an autopsy and tissue donation program. Despite similar presentations, discordance between clinical diagnosis and neuropathologic diagnosis was observed in 28% of those with tissue diagnoses. Most of the families were successfully re-contacted, and significant refinement and supplementation of the data was achieved. We concluded that serial contact with longitudinal evaluation of families has significant implications for genetic analyses. PMID:18361431

Over-representation of the APOE*4 allele in autopsy confirmed early- and late-onset sporadic Alzheimer`s disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kamboh, M.I.; DeKosky, S.T.; Ferrell, R.E.

1994-09-01

Apolipoprotein E binds to {beta}-amyloid peptide in senile plaques and neurofibrillary tangles in Alzheimer`s disease (AD). Recent studies have identified the APOE*4 allele as a major predisposing genetic factor for late-onset familial AD as well as in sporadic AD. Most of these association studies are based on clinically diagnosed AD cases with little data available on autopsy confirmed, definite AD. To characterize the distribution of APOE polymorphism in autopsy confirmed sporadic AD cases, we determined APOE genotypes in 111 DNA samples (aged 51-101 years) extracted from brain tissues which were available from the University of Pittsburgh Alzheimer`s Disease Research Center.more » The APOE data was compared between the AD group and 3 samples of population controls from Western Pennsylvania consisting of a young cohort (N=473, aged 18-48 years), middle cohort (N=473, aged 42-50 years) and an old cohort (N=870, aged 65-90 years). The frequency of the APOE*4 allele was similar in the young and middle cohorts (0.12) and slightly lower in the old cohort (0.10). However, the frequency of the APOE*4 allele was three times higher in both early-onset (<65 years; 0.36) and late-onset ({ge}65 years; 0.38) sporadic AD cases compared to the control groups (p<0.0001). In the AD cohort the frequency of the APOE*4 allele was similar across all age groups (<65, 65-75, 76-85, 86+) and so was in men and women (0.40 vs. 0.37). The E*4 homozygosity was observed in 18% of AD cases compared to 1% in each of the three control groups. The E*4 heterozygosity was present in 50% of AD cases compared to 17% in the control old cohort and 22% in both the young and middle control cohorts. These data confirm that the APOE*4 allele is a major risk factor for AD regardless of age-at-diagnosis or family history.« less

Effects of multiple genetic loci on age at onset in late-onset Alzheimer disease: a genome-wide association study.

PubMed

Naj, Adam C; Jun, Gyungah; Reitz, Christiane; Kunkle, Brian W; Perry, William; Park, Yo Son; Beecham, Gary W; Rajbhandary, Ruchita A; Hamilton-Nelson, Kara L; Wang, Li-San; Kauwe, John S K; Huentelman, Matthew J; Myers, Amanda J; Bird, Thomas D; Boeve, Bradley F; Baldwin, Clinton T; Jarvik, Gail P; Crane, Paul K; Rogaeva, Ekaterina; Barmada, M Michael; Demirci, F Yesim; Cruchaga, Carlos; Kramer, Patricia L; Ertekin-Taner, Nilufer; Hardy, John; Graff-Radford, Neill R; Green, Robert C; Larson, Eric B; St George-Hyslop, Peter H; Buxbaum, Joseph D; Evans, Denis A; Schneider, Julie A; Lunetta, Kathryn L; Kamboh, M Ilyas; Saykin, Andrew J; Reiman, Eric M; De Jager, Philip L; Bennett, David A; Morris, John C; Montine, Thomas J; Goate, Alison M; Blacker, Deborah; Tsuang, Debby W; Hakonarson, Hakon; Kukull, Walter A; Foroud, Tatiana M; Martin, Eden R; Haines, Jonathan L; Mayeux, Richard P; Farrer, Lindsay A; Schellenberg, Gerard D; Pericak-Vance, Margaret A; Albert, Marilyn S; Albin, Roger L; Apostolova, Liana G; Arnold, Steven E; Barber, Robert; Barnes, Lisa L; Beach, Thomas G; Becker, James T; Beekly, Duane; Bigio, Eileen H; Bowen, James D; Boxer, Adam; Burke, James R; Cairns, Nigel J; Cantwell, Laura B; Cao, Chuanhai; Carlson, Chris S; Carney, Regina M; Carrasquillo, Minerva M; Carroll, Steven L; Chui, Helena C; Clark, David G; Corneveaux, Jason; Cribbs, David H; Crocco, Elizabeth A; DeCarli, Charles; DeKosky, Steven T; Dick, Malcolm; Dickson, Dennis W; Duara, Ranjan; Faber, Kelley M; Fallon, Kenneth B; Farlow, Martin R; Ferris, Steven; Frosch, Matthew P; Galasko, Douglas R; Ganguli, Mary; Gearing, Marla; Geschwind, Daniel H; Ghetti, Bernardino; Gilbert, John R; Glass, Jonathan D; Growdon, John H; Hamilton, Ronald L; Harrell, Lindy E; Head, Elizabeth; Honig, Lawrence S; Hulette, Christine M; Hyman, Bradley T; Jicha, Gregory A; Jin, Lee-Way; Karydas, Anna; Kaye, Jeffrey A; Kim, Ronald; Koo, Edward H; Kowall, Neil W; Kramer, Joel H; LaFerla, Frank M; Lah, James J; Leverenz, James B; Levey, Allan I; Li, Ge; Lieberman, Andrew P; Lin, Chiao-Feng; Lopez, Oscar L; Lyketsos, Constantine G; Mack, Wendy J; Martiniuk, Frank; Mash, Deborah C; Masliah, Eliezer; McCormick, Wayne C; McCurry, Susan M; McDavid, Andrew N; McKee, Ann C; Mesulam, Marsel; Miller, Bruce L; Miller, Carol A; Miller, Joshua W; Murrell, Jill R; Olichney, John M; Pankratz, Vernon S; Parisi, Joseph E; Paulson, Henry L; Peskind, Elaine; Petersen, Ronald C; Pierce, Aimee; Poon, Wayne W; Potter, Huntington; Quinn, Joseph F; Raj, Ashok; Raskind, Murray; Reisberg, Barry; Ringman, John M; Roberson, Erik D; Rosen, Howard J; Rosenberg, Roger N; Sano, Mary; Schneider, Lon S; Seeley, William W; Smith, Amanda G; Sonnen, Joshua A; Spina, Salvatore; Stern, Robert A; Tanzi, Rudolph E; Thornton-Wells, Tricia A; Trojanowski, John Q; Troncoso, Juan C; Valladares, Otto; Van Deerlin, Vivianna M; Van Eldik, Linda J; Vardarajan, Badri N; Vinters, Harry V; Vonsattel, Jean Paul; Weintraub, Sandra; Welsh-Bohmer, Kathleen A; Williamson, Jennifer; Wishnek, Sarah; Woltjer, Randall L; Wright, Clinton B; Younkin, Steven G; Yu, Chang-En; Yu, Lei

2014-11-01

Because APOE locus variants contribute to risk of late-onset Alzheimer disease (LOAD) and to differences in age at onset (AAO), it is important to know whether other established LOAD risk loci also affect AAO in affected participants. To investigate the effects of known Alzheimer disease risk loci in modifying AAO and to estimate their cumulative effect on AAO variation using data from genome-wide association studies in the Alzheimer Disease Genetics Consortium. The Alzheimer Disease Genetics Consortium comprises 14 case-control, prospective, and family-based data sets with data on 9162 participants of white race/ethnicity with Alzheimer disease occurring after age 60 years who also had complete AAO information, gathered between 1989 and 2011 at multiple sites by participating studies. Data on genotyped or imputed single-nucleotide polymorphisms most significantly associated with risk at 10 confirmed LOAD loci were examined in linear modeling of AAO, and individual data set results were combined using a random-effects, inverse variance-weighted meta-analysis approach to determine whether they contribute to variation in AAO. Aggregate effects of all risk loci on AAO were examined in a burden analysis using genotype scores weighted by risk effect sizes. Age at disease onset abstracted from medical records among participants with LOAD diagnosed per standard criteria. Analysis confirmed the association of APOE with earlier AAO (P = 3.3 × 10(-96)), with associations in CR1 (rs6701713, P = 7.2 × 10(-4)), BIN1 (rs7561528, P = 4.8 × 10(-4)), and PICALM (rs561655, P = 2.2 × 10(-3)) reaching statistical significance (P < .005). Risk alleles individually reduced AAO by 3 to 6 months. Burden analyses demonstrated that APOE contributes to 3.7% of the variation in AAO (R(2) = 0.256) over baseline (R(2) = 0.221), whereas the other 9 loci together contribute to 2.2% of the variation (R(2) = 0.242). We confirmed an association of APOE (OMIM 107741) variants with AAO among

Polygenic risk score of sporadic late-onset Alzheimer's disease reveals a shared architecture with the familial and early-onset forms.

PubMed

Cruchaga, Carlos; Del-Aguila, Jorge L; Saef, Benjamin; Black, Kathleen; Fernandez, Maria Victoria; Budde, John; Ibanez, Laura; Deming, Yuetiva; Kapoor, Manav; Tosto, Giuseppe; Mayeux, Richard P; Holtzman, David M; Fagan, Anne M; Morris, John C; Bateman, Randall J; Goate, Alison M; Harari, Oscar

2018-02-01

To determine whether the extent of overlap of the genetic architecture among the sporadic late-onset Alzheimer's Disease (sLOAD), familial late-onset AD (fLOAD), sporadic early-onset AD (sEOAD), and autosomal dominant early-onset AD (eADAD). Polygenic risk scores (PRSs) were constructed using previously identified 21 genome-wide significant loci for LOAD risk. We found that there is an overlap in the genetic architecture among sEOAD, fLOAD, and sLOAD. The highest association of the PRS and risk (odds ratio [OR] = 2.27; P = 1.29 × 10 -7 ) was observed in sEOAD, followed by fLOAD (OR = 1.75; P = 1.12 × 10 -7 ) and sLOAD (OR = 1.40; P = 1.21 × 10 -3 ). The PRS was associated with cerebrospinal fluid ptau 181 -Aβ 42 on eADAD (P = 4.36 × 10 -2 ). Our analysis confirms that the genetic factors identified for LOAD modulate risk in sLOAD and fLOAD and also sEOAD cohorts. Specifically, our results suggest that the burden of these risk variants is associated with familial clustering and earlier onset of AD. Although these variants are not associated with risk in the eADAD, they may be modulating age at onset. Copyright © 2017 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Genetic Factors Affecting Late-Onset Alzheimer's Disease Susceptibility.

PubMed

Rezazadeh, Maryam; Khorrami, Aziz; Yeghaneh, Tarlan; Talebi, Mahnaz; Kiani, Seyed Jalal; Heshmati, Yaser; Gharesouran, Jalal

2016-03-01

Alzheimer's disease is considered a progressive brain disease in the older population. Late-onset Alzheimer's disease (LOAD) as a multifactorial dementia has a polygenic inheritance. Age, environment, and lifestyle along with a growing number of genetic factors have been reported as risk factors for LOAD. Our aim was to present results of LOAD association studies that have been done in northwestern Iran, and we also explored possible interactions with apolipoprotein E (APOE) status. We re-evaluated the association of these markers in dominant, recessive, and additive models. In all, 160 LOAD and 163 healthy control subjects of Azeri Turkish ethnicity were studied. The Chi-square test with Yates' correction and Fisher's exact test were used for statistical analysis. A Bonferroni-corrected p value, based on the number of statistical tests, was considered significant. Our results confirmed that chemokine receptor type 2 (CCR2), estrogen receptor 1 (ESR1), toll-like receptor 2 (TLR2), tumor necrosis factor alpha (TNF α), APOE, bridging integrator 1 (BIN1), and phosphatidylinositol-binding clathrin assembly protein (PICALM) are LOAD susceptibility loci in Azeri Turk ancestry populations. Among them, variants of CCR2, ESR1, TNF α, and APOE revealed associations in three different genetic models. After adjusting for APOE, the association (both allelic and genotypic) with CCR2, BIN1, and ESRα (PvuII) was evident only among subjects without the APOE ε4, whereas the association with CCR5, without Bonferroni correction, was significant only among subjects carrying the APOE ε4 allele. This result is an evidence of a synergistic and antagonistic effect of APOE on variant associations with LOAD.

Whole Exome Analysis of Early Onset Alzheimer’s Disease

DTIC Science & Technology

2013-04-01

FTD), FTD with Parkinsonism , and early-onset Alzheimer Disease (EOAD)-like presentations. Using whole exome capture with subsequent sequencing, we...dementia. The MAPT R406W mutation is associated with EOAD-like symptoms and Parkinsonism without FTD, as well as distinct cognitive courses. KEY...OUTCOMES: Carney RM, Kohli MA, Kunkle BW, Naj AC, Gilbert JR, Züchner S, PERICAK-VANCE MA, Parkinsonism and distinct dementia patterns in a

Chronic Mild Stress Assay Leading to Early Onset and Propagation of Alzheimer's Disease Phenotype in Mouse Models.

PubMed

Cuadrado-Tejedor, Mar; García-Osta, Ana

2016-01-01

A comprehensive chronic mild stress (CMS) procedure is presented, which consists in the application of unpredictable mild stressors to animal models in a random order for several weeks. This assay can be applied to Alzheimer's disease (AD) mouse models, leading to accelerated onset and increased severity of AD phenotypes and signs, including memory deficits and the accumulation of amyloid-β and phospho-tau. These assays open the way towards advanced studies on the influence of sustained mild stress, stress responses and pathways on the onset and propagation of Alzheimer's disease.

The effect of APOE and other common genetic variants on the onset of Alzheimer's disease and dementia: a community-based cohort study.

PubMed

van der Lee, Sven J; Wolters, Frank J; Ikram, M Kamran; Hofman, Albert; Ikram, M Arfan; Amin, Najaf; van Duijn, Cornelia M

2018-05-01

Alzheimer's disease is one of the most heritable diseases in elderly people and the most common type of dementia. In addition to the major genetic determinant of Alzheimer's disease, the APOE gene, 23 genetic variants have been associated with the disease. We assessed the effects of these variants and APOE on cumulative risk and age at onset of Alzheimer's disease and all-cause dementia. We studied incident dementia in cognitively healthy participants (aged >45 years) from the community-based Rotterdam Study, an ongoing prospective cohort study based in Rotterdam, the Netherlands, focusing on neurological, cardiovascular, endocrine, and ophthalmological disorders, and other diseases in elderly people. The Rotterdam Study comprises participants in three baseline cohorts (initiated in 1990, 2000, and 2006), who are re-invited to the research centre every 3-4 years, and continuously monitored by records from general practitioners and medical specialists. Cumulative incidence curves up to age 100 years were calculated for Alzheimer's disease and dementia, taking into account mortality as a competing event. These risk curves were stratified by APOE genotypes, tertiles of a weighted genetic risk score (GRS) of 23 Alzheimer's disease-associated genetic variants, and parental history of dementia. 12 255 of 14 926 participants (58·5% women) from the Rotterdam Study were included in this study. During a median follow-up of 11·0 years (IQR 4·9-15·9; 133 123 person years), 1609 participants developed dementia, of whom 1262 (78%) were classified as having Alzheimer's disease; 3310 people died of causes other than dementia. Both APOE and the GRS significantly modified the risks of Alzheimer's disease and dementia. There was evidence for a significant interaction between APOE genotypes and the GRS for the association with Alzheimer's disease (p=0·03) and dementia (p=0·04); the risk for carriers homozygous for APOE ε4 was modified most by the GRS. In carriers

Regional neuronal network failure and cognition in late-onset sporadic Alzheimer disease.

PubMed

Carter, S F; Embleton, K V; Anton-Rodriguez, J M; Burns, A; Ralph, M A L; Herholz, K

2014-06-01

The severe cognitive deficits in Alzheimer disease are associated with structural lesions in gray and white matter in addition to changes in synaptic function. The current investigation studied the breakdown of the structure and function in regional networks involving the Papez circuit and extended neocortical association areas. Cortical volumetric and diffusion tensor imaging (3T MR imaging), positron-emission tomography with (18)F fluorodeoxyglucose on a high-resolution research tomograph, and comprehensive neuropsychological assessments were performed in patients with late-onset sporadic Alzheimer disease, those with mild cognitive impairment, and elderly healthy controls. Atrophy of the medial temporal lobes was the strongest and most consistent abnormality in patients with mild cognitive impairment and Alzheimer disease. Atrophy in the temporal, frontal, and parietal regions was most strongly related to episodic memory deficits, while deficits in semantic cognition were also strongly related to reductions of glucose metabolism in the posterior cingulate cortex and temporoparietal regions. Changes in fractional anisotropy within white matter tracts, particularly in the left cingulum bundle, uncinate fasciculus, superior longitudinal fasciculus, and inferior fronto-occipital fasciculus, were significantly associated with the cognitive deficits in multiple regression analyses. Posterior cingulate and orbitofrontal metabolic deficits appeared to be related to microstructural changes in projecting white matter tracts. Many lesioned network components within the Papez circuit and extended neocortical association areas were significantly associated with cognitive dysfunction in both mild cognitive impairment and late-onset sporadic Alzheimer disease. Hippocampal atrophy was the most prominent lesion, with associated impairment of the uncinate and cingulum white matter microstructures and hippocampal and posterior cingulate metabolic impairment. © 2014 by American

[Mutations of amyloid precursor protein in early-onset familial Alzheimer's disease].

PubMed

Naruse, S; Tsuji, S; Miyatake, T

1992-09-01

Genetic linkage studies of familial Alzheimer's disease (FAD) have suggested that some form of early-onset FAD is linked to proximal long arm of chromosome 21. It has been also suggested that some form of late-onset FAD is linked to long arm of chromosome 19. Goate et al have identified a mis-sense mutation (Val to Ile) in exon 17 of the amyloid precursor protein (APP) gene in 2 of 16 early-onset FAD families, and have shown that the FAD locus in an FAD family is tightly linked to the mis-sense mutation. To determine if the mis-sense mutation is observed in different ethnic origine, we have studied some early-onset FAD families. Two early-onset FAD families showed the existence of the mutation. As the mutation has been identified in different ethnic origine and the mutation has not been observed in normal individuals, it strengthen hypothesis that the mutation is pathogenic. Recently, Val to Phe and Val to Gly mutations have been also identified at the same codon (Codon 717) of the APP gene.

The apolipoprotein E/CI/CII gene cluster and late-onset Alzheimer disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu, Chang-En; Nemens, E.; Olson, J.M.

1994-04-01

The chromosome 19 apolipoprotein E/CI/CII gene cluster was examined for evidence of linkage to a familial Alzheimer disease (FAD) locus. The family groups studied were Volga German (VG), early-onset non-VG (ENVG; mean age at onset <60 years), and late-onset families. A genetic association was observed between apolipoprotein E (ApoE) allele E4 and FAD in late-onset families; the E4 allele frequency was .51 in affected subjects, .37 in at-risk subjects, .11 in spouses, and .19 in unrelated controls. The differences between the E4 frequencies in affected subjects versus controls and in at-risk subjects versus controls were highly significant. No association betweenmore » the E4 allele and FAD was observed in the ENVG or VG groups. A statistically significant allelic association between E4 and AD was also observed in a group of unrelated subjects; the E4 frequency was .26 in affected subjects, versus .19 in controls (Z[sub SND] = 2.20, P < .03). Evidence of linkage of ApoE and ApoCII to FAD was examined by maximum-likelihood methods, using three models and assuming autosomal dominant inheritance: (1) age-dependent penetrance, (2) extremely low (1%) penetrance, and (3) age-dependent penetrance corrected for sporadic Alzheimer disease (AD). For ApoCII in late-onset families, results for close linkage were negative, and only small positive lod-score-statistic (Z) values were obtained. For ApoE in late-onset kindreds, positive Z values were obtained when either allele frequencies from controls or allele frequencies from the families were used. When linkage disequilibrium was incorporated into the analysis, the Z values increased. For the ENVG group, results for ApoE and ApoCII were uniformly negative. Affected-pedigree-member analysis gave significant results for the late-onset kindreds, for ApoE, when control allele frequencies were used but not when allele frequencies were derived from the families. 58 refs., 6 tabs.« less

Whole-genome sequencing suggests a chemokine gene cluster that modifies age at onset in familial Alzheimer's disease

PubMed Central

Lalli, M A; Bettcher, B M; Arcila, M L; Garcia, G; Guzman, C; Madrigal, L; Ramirez, L; Acosta-Uribe, J; Baena, A; Wojta, K J; Coppola, G; Fitch, R; de Both, M D; Huentelman, M J; Reiman, E M; Brunkow, M E; Glusman, G; Roach, J C; Kao, A W; Lopera, F; Kosik, K S

2015-01-01

We have sequenced the complete genomes of 72 individuals affected with early-onset familial Alzheimer's disease caused by an autosomal dominant, highly penetrant mutation in the presenilin-1 (PSEN1) gene, and performed genome-wide association testing to identify variants that modify age at onset (AAO) of Alzheimer's disease. Our analysis identified a haplotype of single-nucleotide polymorphisms (SNPs) on chromosome 17 within a chemokine gene cluster associated with delayed onset of mild-cognitive impairment and dementia. Individuals carrying this haplotype had a mean AAO of mild-cognitive impairment at 51.0±5.2 years compared with 41.1±7.4 years for those without these SNPs. This haplotype thus appears to modify Alzheimer's AAO, conferring a large (~10 years) protective effect. The associated locus harbors several chemokines including eotaxin-1 encoded by CCL11, and the haplotype includes a missense polymorphism in this gene. Validating this association, we found plasma eotaxin-1 levels were correlated with disease AAO in an independent cohort from the University of California San Francisco Memory and Aging Center. In this second cohort, the associated haplotype disrupted the typical age-associated increase of eotaxin-1 levels, suggesting a complex regulatory role for this haplotype in the general population. Altogether, these results suggest eotaxin-1 as a novel modifier of Alzheimer's disease AAO and open potential avenues for therapy. PMID:26324103

Whole-genome sequencing suggests a chemokine gene cluster that modifies age at onset in familial Alzheimer's disease.

PubMed

Lalli, M A; Bettcher, B M; Arcila, M L; Garcia, G; Guzman, C; Madrigal, L; Ramirez, L; Acosta-Uribe, J; Baena, A; Wojta, K J; Coppola, G; Fitch, R; de Both, M D; Huentelman, M J; Reiman, E M; Brunkow, M E; Glusman, G; Roach, J C; Kao, A W; Lopera, F; Kosik, K S

2015-11-01

We have sequenced the complete genomes of 72 individuals affected with early-onset familial Alzheimer's disease caused by an autosomal dominant, highly penetrant mutation in the presenilin-1 (PSEN1) gene, and performed genome-wide association testing to identify variants that modify age at onset (AAO) of Alzheimer's disease. Our analysis identified a haplotype of single-nucleotide polymorphisms (SNPs) on chromosome 17 within a chemokine gene cluster associated with delayed onset of mild-cognitive impairment and dementia. Individuals carrying this haplotype had a mean AAO of mild-cognitive impairment at 51.0 ± 5.2 years compared with 41.1 ± 7.4 years for those without these SNPs. This haplotype thus appears to modify Alzheimer's AAO, conferring a large (~10 years) protective effect. The associated locus harbors several chemokines including eotaxin-1 encoded by CCL11, and the haplotype includes a missense polymorphism in this gene. Validating this association, we found plasma eotaxin-1 levels were correlated with disease AAO in an independent cohort from the University of California San Francisco Memory and Aging Center. In this second cohort, the associated haplotype disrupted the typical age-associated increase of eotaxin-1 levels, suggesting a complex regulatory role for this haplotype in the general population. Altogether, these results suggest eotaxin-1 as a novel modifier of Alzheimer's disease AAO and open potential avenues for therapy.

Completed suicide in an autopsy-confirmed case of early onset Alzheimer's disease.

PubMed

Hartzell, Jennifer Wiener; Geary, Richard; Gyure, Kymberly; Chivukula, Venkata Ravi; Haut, Marc W

2018-04-01

We report a case of a 57-year-old male with clinically diagnosed and autopsy-confirmed early onset Alzheimer's disease who completed suicide by gunshot wound to the chest. This case has several unique aspects that have not been discussed in previous case reports of completed suicide in Alzheimer's disease. In particular, our patient's death was highly planned with successful compensation for his cognitive deficits. After all firearms had been removed from the home as a safety precaution, he obtained a new weapon, hid it and left himself cues to find and use it. The case is discussed in the context of literature differentiating the neural circuitry propagating impulsive versus planned suicidal acts.

Apolipoprotein E type epsilon4 allele, heritability and age at onset in twins with Alzheimer disease and vascular dementia.

PubMed

Bergem, A L; Lannfelt, L

1997-11-01

The apolipoprotein E (APOE) epsilon4 allele is a risk factor in Alzheimer disease (AD), but not in vascular dementia (VaD). We have investigated whether the epsilon4 allele is more common in twin pairs concordant for AD, compared with those discordant for AD, and whether the epsilon4 allele is more common in AD twins than in VaD twins. In addition, we have investigated the relationship of the epsilon4 allele and the age at onset in AD and VaD. APOE genotype was analysed in 29 senile demented twin pairs. The epsilon4 allele was associated with AD and not with VaD. However, there was no difference in the frequency of the APOE epsilon4 allele in concordant (33.3%) and discordant (31.3%) AD dizygotic twin pairs. Age at onset in AD was significantly lower in epsilon4 homozygotes than in individuals with one or no copies of epsilon4 (62.4 vs. 73.5, p<0.01). In concordant AD twin pairs, the epsilon4 allele frequency was somewhat higher in the twins with earlier onset (41.7% vs. 25%), but the difference was not statistically significant. In the VaD group the age at onset was not significantly different between individuals with or without epsilon4 in their genotypes.

Apolipoprotein E alleles in Alzheimer`s and Parkinson`s patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poduslo, S.E.; Schwankhaus, J.D.

1994-09-01

A number of investigators have found an association between the apolipoprotein E4 allele and Alzheimer`s disease. The E4 allele appears at a higher frequency in late onset familial Alzheimer`s patients. In our studies we obtained blood samples from early and late onset familial and sporadic Alzheimer`s patients and spouses, as well as from Parkinson`s patients. The patients were diagnosed as probable Alzheimer`s patients after a neurological examination, extensive blood work, and a CAT scan. The diagnosis was made according to the NINCDS-ADRDA criteria. The apolipoprotein E4 polymorphism was detected after PCR amplification of genomic DNA, restriction enzyme digestion with Hhal,more » and polyacrylamide gel electrophoresis. Ethidium bromide-stained bands at 91 bp were designated as allele 3, at 83 bp as allele 2, and at 72 bp as allele 4. Of the 84 probable Alzheimer`s patients (all of whom were Caucasian), 47 were heterozygous and 13 were homozygous for the E4 allele. There were 26 early onset patients; 13 were heterozygous and 7 homozygous for the E4 allele. The frequencies for the E4 allele for late onset familial patients was 0.45 and for sporadic patients was 0.37. We analyzed 77 spouses with an average age of 71.9 {plus_minus} 7.4 years as controls, and 15 were heterozygous for the E4 allele for an E4 frequency of 0.097. Of the 53 Parkinson`s patients, 11 had the E4 allele for a frequency of 0.113. Thus our findings support the association of the ApoE4 allele with Alzheimer`s disease.« less

TDP-43 stage, mixed pathologies, and clinical Alzheimer's-type dementia.

PubMed

James, Bryan D; Wilson, Robert S; Boyle, Patricia A; Trojanowski, John Q; Bennett, David A; Schneider, Julie A

2016-11-01

Hyperphosphorylated transactive response DNA-binding protein 43 (TDP-43, encoded by TARDBP ) proteinopathy has recently been described in ageing and in association with cognitive impairment, especially in the context of Alzheimer's disease pathology. To explore the role of mixed Alzheimer's disease and TDP-43 pathologies in clinical Alzheimer's-type dementia, we performed a comprehensive investigation of TDP-43, mixed pathologies, and clinical Alzheimer's-type dementia in a large cohort of community-dwelling older subjects. We tested the hypotheses that TDP-43 with Alzheimer's disease pathology is a common mixed pathology; is related to increased likelihood of expressing clinical Alzheimer's-type dementia; and that TDP-43 pathologic stage is an important determinant of clinical Alzheimer's-type dementia. Data came from 946 older adults with ( n = 398) and without dementia ( n = 548) from the Rush Memory and Aging Project and Religious Orders Study. TDP-43 proteinopathy (cytoplasmic inclusions) was present in 496 (52%) subjects, and the pattern of deposition was classified as stage 0 (none; 48%), stage 1 (amygdala; 18%), stage 2 (extension to hippocampus/entorhinal; 21%), or stage 3 (extension to neocortex; 14%). TDP-43 pathology combined with a pathologic diagnosis of Alzheimer's disease was a common mixed pathology (37% of all participants), and the proportion of subjects with clinical Alzheimer's-type dementia formerly labelled 'pure pathologic diagnosis of Alzheimer's disease' was halved when TDP-43 was considered. In logistic regression models adjusted for age, sex, and education, TDP-43 pathology was associated with clinical Alzheimer's-type dementia (odds ratio = 1.51, 95% confidence interval = 1.11, 2.05) independent of pathological Alzheimer's disease (odds ratio = 4.30, 95% confidence interval = 3.08, 6.01) or other pathologies (infarcts, arteriolosclerosis, Lewy bodies, and hippocampal sclerosis). Mixed Alzheimer's disease and TDP-43 pathologies were

Identification of a novel valosin-containing protein polymorphism in late-onset Alzheimer's disease.

PubMed

Kaleem, M; Zhao, A; Hamshere, M; Myers, A J

2007-01-01

Recently, mutations in the valosin-containing protein gene (VCP) were found to be causative for a rare form of dementia [Watts GDJ, et al.: Nat Genet 2004;36:377-381]. This gene lies within a region on the genome that has been linked to late onset Alzheimer's disease (LOAD) [Myers A, et al.: Am J Med Genet 2002;114:233-242]. In this study, we investigated whether variation within VCP could account for the LOAD linkage peak on chromosome 9. We sequenced 188 individuals from the set of sibling pairs we had used to obtain the linkage results for chromosome 9 to look for novel polymorphisms that could explain the linkage signal. Any variant that was found was then typed in 2 additional sets of neuropathologically confirmed samples to look for associations with Alzheimer's disease. We found 2 variants when we sequenced VCP. One was a novel rare variant (R92H) and the other is already reported within the publicly available databases (rs10972300). Neither explained the chromosome 9 linkage signal for LOAD. We have found a novel rare variant within the VCP gene, but we did not find a variant that could explain the linkage signal for LOAD on chromosome 9. Copyright (c) 2007 S. Karger AG, Basel.

Experimental induction of type 2 diabetes in aging-accelerated mice triggered Alzheimer-like pathology and memory deficits.

PubMed

Mehla, Jogender; Chauhan, Balwantsinh C; Chauhan, Neelima B

2014-01-01

Alzheimer's disease (AD) is an age-dependent neurodegenerative disease constituting ~95% of late-onset non-familial/sporadic AD, and only ~5% accounting for early-onset familial AD. Availability of a pertinent model representing sporadic AD is essential for testing candidate therapies. Emerging evidence indicates a causal link between diabetes and AD. People with diabetes are >1.5-fold more likely to develop AD. Senescence-accelerated mouse model (SAMP8) of accelerated aging displays many features occurring early in AD. Given the role played by diabetes in the pre-disposition of AD, and the utility of SAMP8 non-transgenic mouse model of accelerated aging, we examined if high fat diet-induced experimental type 2 diabetes in SAMP8 mice will trigger pathological aging of the brain. Results showed that compared to non-diabetic SAMP8 mice, diabetic SAMP8 mice exhibited increased cerebral amyloid-β, dysregulated tau-phosphorylating glycogen synthase kinase 3β, reduced synaptophysin immunoreactivity, and displayed memory deficits, indicating Alzheimer-like changes. High fat diet-induced type 2 diabetic SAMP8 mice may represent the metabolic model of AD.

Proximity to Parental Symptom Onset and Amyloid-β Burden in Sporadic Alzheimer Disease.

PubMed

Villeneuve, Sylvia; Vogel, Jacob W; Gonneaud, Julie; Pichet Binette, Alexa; Rosa-Neto, Pedro; Gauthier, Serge; Bateman, Randall J; Fagan, Anne M; Morris, John C; Benzinger, Tammie L S; Johnson, Sterling C; Breitner, John C S; Poirier, Judes

2018-05-01

Alzheimer disease (AD) develops during several decades. Presymptomatic individuals might be the best candidates for clinical trials, but their identification is challenging because they have no symptoms. To assess whether a sporadic parental estimated years to symptom onset calculation could be used to identify information about amyloid-β (Aβ) levels in asymptomatic individuals with a parental history of AD dementia. This cohort study analyzed Aβ1-42 in cerebrospinal fluid (CSF) specimens from 101 cognitively normal individuals who had a lumbar puncture as part of the Presymptomatic Evaluation of Novel or Experimental Treatments for Alzheimer Disease (PREVENT-AD) cohort from September 1, 2011, through November 30, 2016 (374 participants were enrolled in the cohort during this period). The study estimated each participant's proximity to his/her parent's symptom onset by subtracting the index relative's onset age from his/her current age. The association between proximity to parental symptom onset and Aβ levels was then assessed using apolipoprotein E ε4 (APOE4) status and sex as interactive terms. These analyses were performed again in 2 independent cohorts using CSF and Pittsburgh compound B carbon 11-labeled positron emission tomography (PIB-PET) Aβ biomarkers: the Adult Children Study (ACS) and the Wisconsin Registry for Alzheimer Prevention (WRAP) cohorts. The association between proximity to parental symptom onset and Aβ burden in asymptomatic individuals with a parental history of sporadic AD. The present analysis included a subset of 101 PREVENT-AD individuals (mean [SD] age, 61.8 [5.1] years; 30 [29.7%] male), 128 ACS participants (112 participants underwent CSF measurement: mean [SD] age, 63.4 [5.1] years; 31 [27.7%] male; and 107 underwent PIB-PET: mean [SD] age, 64.6 [5.3] years; 27 [25.2%] male), and 135 WRAP participants (85 participants underwent CSF measurement: mean [SD] age, 59.9 [6.0] years; 27 [31.8%] male; and 135 underwent PIB-PET: mean

Traumatic brain injury history is associated with an earlier age of dementia onset in autopsy-confirmed Alzheimer's disease.

PubMed

Schaffert, Jeff; LoBue, Christian; White, Charles L; Chiang, Hsueh-Sheng; Didehbani, Nyaz; Lacritz, Laura; Rossetti, Heidi; Dieppa, Marisara; Hart, John; Cullum, C Munro

2018-05-01

To evaluate whether a history of traumatic brain injury (TBI) with reported loss of consciousness (LOC) is a risk factor for earlier onset of Alzheimer's disease (AD) in an autopsy-confirmed sample. Data from 2,133 participants with autopsy-confirmed AD (i.e., at least Braak neurofibrillary tangle stages III to VI and CERAD neuritic plaque score moderate to frequent) were obtained from the National Alzheimer's Coordinating Center (NACC). Participants were categorized by presence/absence of self-reported remote (i.e., >1 year prior to their first Alzheimer's Disease Center visit) history of TBI with LOC (TBI+ vs. TBI-). Analyses of Covariance (ANCOVA) controlling for sex, education, and race compared groups on clinician-estimated age of symptom onset and age of diagnosis. Average age of onset was 2.34 years earlier (p = .01) for the TBI+ group (n = 194) versus the TBI- group (n = 1900). Dementia was diagnosed on average 2.83 years earlier (p = .002) in the TBI+ group (n = 197) versus the TBI- group (n = 1936). Using more stringent neuropathological criteria (i.e., Braak stages V-VI and CERAD frequent), both age of AD onset and diagnosis were 3.6 years earlier in the TBI+ group (both p's < .001). History of TBI with reported LOC appears to be a risk factor for earlier AD onset. This is the first study to use autopsy-confirmed cases, supporting previous investigations that used clinical criteria for the diagnosis of AD. Further investigation as to possible underlying mechanisms of association is needed. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Activation of the Cannabinoid Type 2 Receptor by a Novel Indazole Derivative Normalizes the Survival Pattern of Lymphoblasts from Patients with Late-Onset Alzheimer's Disease.

PubMed

Del Cerro, Patricia; Alquézar, Carolina; Bartolomé, Fernando; González-Naranjo, Pedro; Pérez, Concepción; Carro, Eva; Páez, Juan A; Campillo, Nuria E; Martín-Requero, Ángeles

2018-05-07

Alzheimer's disease is a multifactorial disorder for which there is no disease-modifying treatment yet. CB2 receptors have emerged as a promising therapeutic target for Alzheimer's disease because they are expressed in neuronal and glial cells and their activation has no psychoactive effects. The aim of this study was to investigate whether activation of the CB2 receptor would restore the aberrant enhanced proliferative activity characteristic of immortalized lymphocytes from patients with late-onset Alzheimer's disease. It is assumed that cell-cycle dysfunction occurs in both peripheral cells and neurons in patients with Alzheimer's disease, contributing to the instigation of the disease. Lymphoblastoid cell lines from patients with Alzheimer's disease and age-matched control individuals were treated with a new, in-house-designed dual drug PGN33, which behaves as a CB2 agonist and butyrylcholinesterase inhibitor. We analyzed the effects of this compound on the rate of cell proliferation and levels of key regulatory proteins. In addition, we investigated the potential neuroprotective action of PGN33 in β-amyloid-treated neuronal cells. We report here that PGN33 normalized the increased proliferative activity of Alzheimer's disease lymphoblasts. The compound blunted the calmodulin-dependent overactivation of the PI3K/Akt pathway, by restoring the cyclin-dependent kinase inhibitor p27 levels, which in turn reduced the activity of the cyclin-dependent kinase/pRb cascade. Moreover, this CB2 agonist prevented β-amyloid-induced cell death in neuronal cells. Our results suggest that the activation of CB2 receptors could be considered a useful therapeutic approach for Alzheimer's disease.

Genetics Home Reference: Alzheimer disease

MedlinePlus

... 65, while the late-onset form appears after age 65. The early-onset form is much less common than the ... familial Alzheimer disease (FAD) Presenile and senile dementia Primary Senile Degenerative Dementia SDAT Related ... autosomal dominant Alzheimer disease Familial Alzheimer disease ...

Allelic association but only weak evidence for linkage to the apolipoprotein E locus in late-onset Swedish Alzheimer families

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, L.; Forsell, C.; Lilius, L.

1996-05-31

An association between the {epsilon}4 allele of the apolipoprotein E gene (APOE) and late-onset Alzheimer`s disease (AD) was recently demonstrated. In order to confirm the association and to gauge the ability of standard genetic linkage methods to identify susceptibility genes, we investigated 15 Swedish late-onset AD families. We found an association of familial AD to the APOE {epsilon}4 allele (P = 0.01) but no indication of linkage to the APOE region using 2-point linkage analysis, and only weak evidence using the affected pedigree-member (APM) method. Our results confirm an APOE {epsilon}4 association with late-onset familial AD and indicate that susceptibilitymore » genes can easily be missed when using standard lod score and APM genetic linkage analysis. 19 refs., 1 fig., 4 tabs.« less

Prevalence of Comorbidity in Patients With Young-Onset Alzheimer Disease Compared With Late-Onset: A Comparative Cohort Study.

PubMed

Gerritsen, Adrie A J; Bakker, Christian; Verhey, Frans R J; de Vugt, Marjolein E; Melis, René J F; Koopmans, Raymond T C M

2016-04-01

With the lack of a cure for Alzheimer disease (AD), the identification of comorbidity is important to reduce the possibility of excess disability. Although comorbidity in patients with late-onset AD (LO-AD) is common, for people with young-onset AD (YO-AD), it is unclear how often comorbidity occurs. Furthermore, it is uncertain whether comorbidity in patients with YO-AD differs from that in patients with LO-AD. The aim of this study was to explore the prevalence, types of morbidity, and morbidity profiles in patients with YO-AD compared with those of patients with LO-AD. Explorative cohort study from 2 separate Dutch cohorts (Needs in Young-onset Dementia [NeedYD] and the Clinical Course of Cognition and Comorbidity-Dementia Study [4C-Dementia study]). Participants were recruited in 2007 and 2008 from (1) the memory clinics of 3 Dutch Alzheimer centers, (2) the memory clinics of general hospitals, (3) mental health services in the southern part of the Netherlands, and (4) young-onset dementia specialized day care facilities. A comparison group of community-dwelling, elderly patients with AD was selected from the 4C-Dementia study. Patients in this study were recruited in 2010 and 2011 from the aforementioned Alzheimer centers. The prevalence rates of comorbidity were compared between 177 patients with YO-AD and 155 patients with LO-AD. Comorbidity was classified using the International Classification of Diseases, 10th Revision (ICD-10). The total amount of comorbidity was established by counting the number of existing diseases (ICD categories or chapters) and comorbidity was also dichotomized as present or absent. Furthermore, a hierarchical cluster analysis was performed to study clusters of comorbidity. Compared with LO-AD, patients with YO-AD showed less (P < .001) overall comorbidity (58.2% vs 86.5%) and had lower prevalence rates of diabetes, obesity, and circulatory diseases; however, the prevalence rates of diseases of the nervous system in YO-AD (6

A common haplotype lowers PU.1 expression in myeloid cells and delays onset of Alzheimer's disease.

PubMed

Huang, Kuan-Lin; Marcora, Edoardo; Pimenova, Anna A; Di Narzo, Antonio F; Kapoor, Manav; Jin, Sheng Chih; Harari, Oscar; Bertelsen, Sarah; Fairfax, Benjamin P; Czajkowski, Jake; Chouraki, Vincent; Grenier-Boley, Benjamin; Bellenguez, Céline; Deming, Yuetiva; McKenzie, Andrew; Raj, Towfique; Renton, Alan E; Budde, John; Smith, Albert; Fitzpatrick, Annette; Bis, Joshua C; DeStefano, Anita; Adams, Hieab H H; Ikram, M Arfan; van der Lee, Sven; Del-Aguila, Jorge L; Fernandez, Maria Victoria; Ibañez, Laura; Sims, Rebecca; Escott-Price, Valentina; Mayeux, Richard; Haines, Jonathan L; Farrer, Lindsay A; Pericak-Vance, Margaret A; Lambert, Jean Charles; van Duijn, Cornelia; Launer, Lenore; Seshadri, Sudha; Williams, Julie; Amouyel, Philippe; Schellenberg, Gerard D; Zhang, Bin; Borecki, Ingrid; Kauwe, John S K; Cruchaga, Carlos; Hao, Ke; Goate, Alison M

2017-08-01

A genome-wide survival analysis of 14,406 Alzheimer's disease (AD) cases and 25,849 controls identified eight previously reported AD risk loci and 14 novel loci associated with age at onset. Linkage disequilibrium score regression of 220 cell types implicated the regulation of myeloid gene expression in AD risk. The minor allele of rs1057233 (G), within the previously reported CELF1 AD risk locus, showed association with delayed AD onset and lower expression of SPI1 in monocytes and macrophages. SPI1 encodes PU.1, a transcription factor critical for myeloid cell development and function. AD heritability was enriched within the PU.1 cistrome, implicating a myeloid PU.1 target gene network in AD. Finally, experimentally altered PU.1 levels affected the expression of mouse orthologs of many AD risk genes and the phagocytic activity of mouse microglial cells. Our results suggest that lower SPI1 expression reduces AD risk by regulating myeloid gene expression and cell function.

Phenotypic Similarities Between Late-Onset Autosomal Dominant and Sporadic Alzheimer Disease: A Single-Family Case-Control Study.

PubMed

Day, Gregory S; Musiek, Erik S; Roe, Catherine M; Norton, Joanne; Goate, Alison M; Cruchaga, Carlos; Cairns, Nigel J; Morris, John C

2016-09-01

The amyloid hypothesis posits that disrupted β-amyloid homeostasis initiates the pathological process resulting in Alzheimer disease (AD). Autosomal dominant AD (ADAD) has an early symptomatic onset and is caused by single-gene mutations that result in overproduction of β-amyloid 42. To the extent that sporadic late-onset AD (LOAD) also results from dysregulated β-amyloid 42, the clinical phenotypes of ADAD and LOAD should be similar when controlling for the effects of age. To use a family with late-onset ADAD caused by a presenilin 1 (PSEN1) gene mutation to mitigate the potential confound of age when comparing ADAD and LOAD. This case-control study was conducted at the Knight Alzheimer Disease Research Center at Washington University, St Louis, Missouri, and other National Institutes of Aging-funded AD centers in the United States. Ten PSEN1 A79V mutation carriers from multiple generations of a family with late-onset ADAD and 12 noncarrier family members were followed up at the Knight Alzheimer Disease Research Center (1985-2015) and 1115 individuals with neuropathologically confirmed LOAD were included from the National Alzheimer Coordinating Center database (September 2005-December 2014). Data analysis was completed in January 2016, including Knight Alzheimer Disease Research Center patient data collected up until the end of 2015. Planned comparison of clinical characteristics between cohorts, including age at symptom onset, associated symptoms and signs, rates of progression, and disease duration. Of the PSEN1 A79V carriers in the family with late-onset ADAD, 4 were female (57%); among those with LOAD, 529 were female (47%). Seven mutation carriers (70%) developed AD dementia, while 3 were yet asymptomatic in their seventh and eighth decades of life. No differences were observed between mutation carriers and individuals with LOAD concerning age at symptom onset (mutation carriers: mean, 75 years [range, 63-77 years] vs those with LOAD: mean, 74 years [range

Evidence that the APOE locus influences rate of disease progression in late onset familial Alzheimer`s disease but is not causative

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bennett, C.; Crawford, F.; Osborne, A.

1995-02-27

An association has been observed in several independent data sets between late onset Alzheimer`s Disease (AD) and the APOE locus on chromosome 19. We have examined the genotype in family history positive (FHP) and family history negative (FHN) cases and find a distortion of the APOE allele frequencies in accord with previous studies. However, when we examined the allele distribution of the at-risk siblings of the FHP group we found an excess of the {epsilon}4 allele which also differs significantly from historic controls but not from the affected siblings. The age distribution of the affected and unaffected siblings was similar,more » suggesting that the allelic frequency distortion in the unaffected siblings was not due to their being below the mean age of onset. Lod score linkage analysis, with age dependent onset and non-stringent specification of the genetic parameters, did not suggest linkage to the APOE locus. Furthermore, an analysis of variance of the age of disease free survival suggested that APOE genotype contributes a small fraction of the total variance indicating that the APOE locus is a poor predictor of disease free survival age within late onset families. One explanation for the age dependent association reported by other groups, and our results, is that the APOE locus enhances the rate of progression of the disease process in otherwise predisposed individuals and that variation at this locus is not able in and of itself to cause the disease. We suggest this hypothesis is compatible with the current literature regarding APOE and AD. 19 refs., 1 fig., 2 tabs.« less

Assessment of risk factors for earlier onset of sporadic Alzheimer's disease dementia.

PubMed

de Oliveira, Fabricio Ferreira; Bertolucci, Paulo Henrique Ferreira; Chen, Elizabeth Suchi; Smith, Marilia Cardoso

2014-01-01

Pharmacological treatment has mild effects for patients with Alzheimer's disease dementia (AD); therefore, the search for modifiable risk factors is an important challenge. Though risk factors for AD are widely recognized, elements that influence the time of dementia onset have not been comprehensively reported. We aimed to investigate which risk factors might be related to the age of onset of AD in a sample of patients with highly variable educational levels, taking into account the Framingham risk scoring as the sole measure of vascular risk. We included 209 consecutive late-onset AD patients to find out which factors among educational levels, coronary heart disease risk estimated by way of Framingham risk scores, history of head trauma or depression, surgical procedures under general anesthesia, family history of neurodegenerative diseases, gender, marital status and APOE haplotypes might be related to the age of dementia onset in this sample of patients with low mean schooling. Mean age of AD onset was 73.38±6.5 years old, unaffected by schooling or family history of neurodegenerative diseases. Patients who were APOE-ε4 carriers, married, or with history of depression, had earlier onset of AD, particularly when they were women. Coronary heart disease risk was marginally significant for later onset of AD. APOE haplotypes, marital status and history of depression were the most important factors to influence the age of AD onset in this sample. While midlife cerebrovascular risk factors may increase incidence of AD, they may lead to later dementia onset when present in late life.

Multilingualism (but not always bilingualism) delays the onset of Alzheimer disease: evidence from a bilingual community.

PubMed

Chertkow, Howard; Whitehead, Victor; Phillips, Natalie; Wolfson, Christina; Atherton, Julie; Bergman, Howard

2010-01-01

A recent paper by Bialystok et al in Neuropsychologia (vol. 45, pgs. 459 to 464) suggested that early bilingualism produced a statistically significant 4.1-year delay in onset of memory loss symptoms in older individuals with Alzheimer disease, possibly reflecting an increase in the cognitive reserve of these individuals. That study focused on multilingual elderly patients of whom 90% were immigrants. Our memory clinic, in Montreal Canada, has the advantage of having a large set of individuals who are either multilingual immigrants to Canada, or who are nonimmigrants but raised in both official languages of Canada--French and English. We thus attempted to replicate the above findings using a larger cohort in a different setting. We examined age at diagnosis of Alzheimer disease and age at symptom onset for all unilingual versus multilingual participants, and then for those who were nonimmigrant English/French bilinguals. Overall, we found a small but significant protective effect of more than 2 languages spoken, but we found no significant benefit in bilinguals overall in relation to age at diagnosis or age at symptom onset. However, in the immigrant group, the results mirrored those of Bialystok et al with 2 or more languages delaying the diagnosis of Alzheimer disease by almost 5 years. A trend toward the same effect was also seen in nonimmigrants whose first language was French. In contrast, in nonimmigrants whose first language was English, no such effect was found. These results are discussed in relation to the earlier findings and the theory of cognitive reserve.

Caregiver burden and psychosocial services in patients with early and late onset Alzheimer's disease.

PubMed

Grønning, Helene; Kristiansen, Susanne; Dyre, Dorte; Rahmani, Abdul; Gyllenborg, Jesper; Høgh, Peter

2013-07-01

The purpose of the study was to analyse caregiver burden and consumption of psychosocial services in a consecutive group of patients with early onset Alzheimer's disease (EOAD) compared with a matching group with late onset Alzheimer's disease (LOAD). This was a case-control study with 42 patients who were matched according to disease severity at the time of diagnosis. Caregivers in both groups were interviewed using the Neuro Psychiatric Inventory (NPI), the Activities of Daily Living (ADL) scale and the Resource Utilization in Dementia scale. The quantitative outcomes were compared statistically. The EOAD group had a significantly higher ADL score than the LOAD group. There was a trend towards caregivers in the LOAD group spending more time helping the patients, and they needed more social services than the EOAD group. NPI scores were not significantly different, but a tendency towards a higher caregiver burden in the EOAD group was observed. The higher caregiver burden in patients with EOAD--despite a better ADL function than LOAD patients--suggests that the existing psychosocial services might be particularly insufficient for caregivers in EOAD. The study was funded by a three-month scholarship grant from the research fund at Roskilde Hospital. not relevant.

Modeling Late-Onset Sporadic Alzheimer's Disease through BMI1 Deficiency.

PubMed

Flamier, Anthony; El Hajjar, Jida; Adjaye, James; Fernandes, Karl J; Abdouh, Mohamed; Bernier, Gilbert

2018-05-29

Late-onset sporadic Alzheimer's disease (AD) is the most prevalent form of dementia, but its origin remains poorly understood. The Bmi1/Ring1 protein complex maintains transcriptional repression of developmental genes through histone H2A mono-ubiquitination, and Bmi1 deficiency in mice results in growth retardation, progeria, and neurodegeneration. Here, we demonstrate that BMI1 is silenced in AD brains, but not in those with early-onset familial AD, frontotemporal dementia, or Lewy body dementia. BMI1 expression was also reduced in cortical neurons from AD patient-derived induced pluripotent stem cells but not in neurons overexpressing mutant APP and PSEN1. BMI1 knockout in human post-mitotic neurons resulted in amyloid beta peptide secretion and deposition, p-Tau accumulation, and neurodegeneration. Mechanistically, BMI1 was required to repress microtubule associated protein tau (MAPT) transcription and prevent GSK3beta and p53 stabilization, which otherwise resulted in neurodegeneration. Restoration of BMI1 activity through genetic or pharmaceutical approaches could represent a therapeutic strategy against AD. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

On the discovery of the genetic association of Apolipoprotein E genotypes and common late-onset Alzheimer disease.

PubMed

Roses, Allen D

2006-01-01

The association of Apolipoprotein E-4 with the age of onset of common late-onset Alzheimer's disease (AD) was originally reported in three 1993 papers from the Duke ADRC (Alzheimer's Disease Research Center) group. The Center was investigating two diverse experimental streams that led to this discovery. The first being a genetic linkage study performed in multiplex familial late-onset AD in which a linkage was discovered at chromosome 19q13. The 1991 multilocus analysis of linkage had been considered very controversial. The second stream came from a series of amyloid-beta binding studies in which a consistent protein "impurity" was present on gel separation analyses. After sequencing this "impurity" band, several tryptic peptide sequences were found to be identical for apoE which, at that time, had no known association with Alzheimer's disease. The flash of recognition was the knowledge that APOE was one of the first genes localized to chromosome 19 in the mid-1980's. Within a three week period in late 1992, a highly significant association was identified in clinical patients from multiplex families, in sporadic clinical patients, and in autopsy diagnosed series. Within the first two months of 1993, it was possible to clearly demonstrate that the APOE isoforms were associated with differing ages of onset, but the course of illness following diagnosis was related more to age than APOE genotype. The earliest submitted paper reported the familial association and amyloid-beta binding. The second reported the association with common sporadic late-onset, [not-known to be familial] AD patients. The third reported that APOE4 carriers had earlier rates of onset of clinical disease than APOE2 or APOE3 carriers. Subsequently, over more than a decade, the biological expression of apoE in human neurons was confirmed as distinct from rodent brain. Proteomic experiments and positron emission tomography data have led to a series of clinical trials with agents selected to increase

Conditional Deletion of Prnp Rescues Behavioral and Synaptic Deficits after Disease Onset in Transgenic Alzheimer's Disease

PubMed Central

Kaufman, Adam C.; Herber, Charlotte S.; Haas, Laura T.; Robinson, Sophie; Lee, Michael K.

2017-01-01

Biochemical and genetic evidence implicate soluble oligomeric amyloid-β (Aβo) in triggering Alzheimer's disease (AD) pathophysiology. Moreover, constitutive deletion of the Aβo-binding cellular prion protein (PrPC) prevents development of memory deficits in APPswe/PS1ΔE9 mice, a model of familial AD. Here, we define the role of PrPC to rescue or halt established AD endophenotypes in a therapeutic disease-modifying time window after symptom onset. Deletion of Prnp at either 12 or 16 months of age fully reverses hippocampal synapse loss and completely rescues preexisting behavioral deficits by 17 months. In contrast, but consistent with a neuronal function for Aβo/PrPC signaling, plaque density, microgliosis, and astrocytosis are not altered. Degeneration of catecholaminergic neurons remains unchanged by PrPC reduction after disease onset. These results define the potential of targeting PrPC as a disease-modifying therapy for certain AD-related phenotypes after disease onset. SIGNIFICANCE STATEMENT The study presented here further elucidates our understanding of the soluble oligomeric amyloid-β–Aβo-binding cellular prion protein (PrPC) signaling pathway in a familial form of Alzheimer's disease (AD) by implicating PrPC as a potential therapeutic target for AD. In particular, genetic deletion of Prnp rescued several familial AD (FAD)-associated phenotypes after disease onset in a mouse model of FAD. This study underscores the therapeutic potential of PrPC deletion given that patients already present symptoms at the time of diagnosis. PMID:28842420

Rare Variants in PLD3 Do Not Affect Risk for Early-Onset Alzheimer Disease in a European Consortium Cohort.

PubMed

Cacace, Rita; Van den Bossche, Tobi; Engelborghs, Sebastiaan; Geerts, Nathalie; Laureys, Annelies; Dillen, Lubina; Graff, Caroline; Thonberg, Håkan; Chiang, Huei-Hsin; Pastor, Pau; Ortega-Cubero, Sara; Pastor, Maria A; Diehl-Schmid, Janine; Alexopoulos, Panagiotis; Benussi, Luisa; Ghidoni, Roberta; Binetti, Giuliano; Nacmias, Benedetta; Sorbi, Sandro; Sanchez-Valle, Raquel; Lladó, Albert; Gelpi, Ellen; Almeida, Maria Rosário; Santana, Isabel; Tsolaki, Magda; Koutroumani, Maria; Clarimon, Jordi; Lleó, Alberto; Fortea, Juan; de Mendonça, Alexandre; Martins, Madalena; Borroni, Barbara; Padovani, Alessandro; Matej, Radoslav; Rohan, Zdenek; Vandenbulcke, Mathieu; Vandenberghe, Rik; De Deyn, Peter P; Cras, Patrick; van der Zee, Julie; Sleegers, Kristel; Van Broeckhoven, Christine

2015-12-01

Rare variants in the phospholipase D3 gene (PLD3) were associated with increased risk for late-onset Alzheimer disease (LOAD). We identified a missense mutation in PLD3 in whole-genome sequence data of a patient with autopsy confirmed Alzheimer disease (AD) and onset age of 50 years. Subsequently, we sequenced PLD3 in a Belgian early-onset Alzheimer disease (EOAD) patient (N = 261) and control (N = 319) cohort, as well as in European EOAD patients (N = 946) and control individuals (N = 1,209) ascertained in different European countries. Overall, we identified 22 rare variants with a minor allele frequency <1%, 20 missense and two splicing mutations. Burden analysis did not provide significant evidence for an enrichment of rare PLD3 variants in EOAD patients in any of the patient/control cohorts. Also, meta-analysis of the PLD3 data, including a published dataset of a German EOAD cohort, was not significant (P = 0.43; OR = 1.53, 95% CI 0.60-3.31). Consequently, our data do not support a role for PLD3 rare variants in the genetic etiology of EOAD in European EOAD patients. Our data corroborate the negative replication data obtained in LOAD studies and therefore a genetic role of PLD3 in AD remains to be demonstrated. © 2015 The Authors. **Human Mutation published by Wiley Periodicals, Inc.

Rare Variants in PLD3 Do Not Affect Risk for Early‐Onset Alzheimer Disease in a European Consortium Cohort

PubMed Central

Cacace, Rita; Van den Bossche, Tobi; Engelborghs, Sebastiaan; Geerts, Nathalie; Laureys, Annelies; Dillen, Lubina; Graff, Caroline; Thonberg, Håkan; Chiang, Huei‐Hsin; Pastor, Pau; Ortega‐Cubero, Sara; Pastor, Maria A.; Diehl‐Schmid, Janine; Alexopoulos, Panagiotis; Benussi, Luisa; Ghidoni, Roberta; Binetti, Giuliano; Nacmias, Benedetta; Sorbi, Sandro; Sanchez‐Valle, Raquel; Lladó, Albert; Gelpi, Ellen; Almeida, Maria Rosário; Santana, Isabel; Tsolaki, Magda; Koutroumani, Maria; Clarimon, Jordi; Lleó, Alberto; Fortea, Juan; de Mendonça, Alexandre; Martins, Madalena; Borroni, Barbara; Padovani, Alessandro; Matej, Radoslav; Rohan, Zdenek; Vandenbulcke, Mathieu; Vandenberghe, Rik; De Deyn, Peter P.; Cras, Patrick; van der Zee, Julie; Sleegers, Kristel

2015-01-01

ABSTRACT Rare variants in the phospholipase D3 gene (PLD3) were associated with increased risk for late‐onset Alzheimer disease (LOAD). We identified a missense mutation in PLD3 in whole‐genome sequence data of a patient with autopsy confirmed Alzheimer disease (AD) and onset age of 50 years. Subsequently, we sequenced PLD3 in a Belgian early‐onset Alzheimer disease (EOAD) patient (N = 261) and control (N = 319) cohort, as well as in European EOAD patients (N = 946) and control individuals (N = 1,209) ascertained in different European countries. Overall, we identified 22 rare variants with a minor allele frequency <1%, 20 missense and two splicing mutations. Burden analysis did not provide significant evidence for an enrichment of rare PLD3 variants in EOAD patients in any of the patient/control cohorts. Also, meta‐analysis of the PLD3 data, including a published dataset of a German EOAD cohort, was not significant (P = 0.43; OR = 1.53, 95% CI 0.60–3.31). Consequently, our data do not support a role for PLD3 rare variants in the genetic etiology of EOAD in European EOAD patients. Our data corroborate the negative replication data obtained in LOAD studies and therefore a genetic role of PLD3 in AD remains to be demonstrated. PMID:26411346

Molecular genetics of early-onset Alzheimer's disease revisited.

PubMed

Cacace, Rita; Sleegers, Kristel; Van Broeckhoven, Christine

2016-06-01

As the discovery of the Alzheimer's disease (AD) genes, APP, PSEN1, and PSEN2, in families with autosomal dominant early-onset AD (EOAD), gene discovery in familial EOAD came more or less to a standstill. Only 5% of EOAD patients are carrying a pathogenic mutation in one of the AD genes or a apolipoprotein E (APOE) risk allele ε4, most of EOAD patients remain unexplained. Here, we aimed at summarizing the current knowledge of EOAD genetics and its role in ongoing approaches to understand the biology of AD and disease symptomatology as well as developing new therapeutics. Next, we explored the possible molecular mechanisms that might underlie the missing genetic etiology of EOAD and discussed how the use of massive parallel sequencing technologies triggered novel gene discoveries. To conclude, we commented on the relevance of reinvestigating EOAD patients as a means to explore potential new avenues for translational research and therapeutic discoveries. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

The Protective Effect of Cantonese/Mandarin Bilingualism on the Onset of Alzheimer Disease.

PubMed

Zheng, Yifan; Wu, Qi; Su, Fengjuan; Fang, Yingying; Zeng, Jinsheng; Pei, Zhong

2018-06-08

Several studies have found that bilingualism can delay the age of onset of Alz-heimer disease (AD). The interpretation of these findings is that switching between two languages can enhance cognitive reserve. However, some studies have provided inconsistent results. Diverse language pairs used by the bilinguals in different studies may contribute to the discrepancies. Cantonese and Mandarin are widely used in southern China, and regarded as bilingualism. The present study aims to determine if Cantonese/Mandarin bilingualism can delay the onset of AD. The data of 129 patients diagnosed with probable AD, including 48 Cantonese monolinguals, 20 Mandarin monolinguals, and 61 Cantonese/Mandarin bilinguals were analyzed. Cantonese/Mandarin bilinguals were found to have an older age at AD onset, and older age at the first clinic visit than Mandarin monolinguals and Cantonese monolinguals. Both Mandarin monolinguals and Cantonese/Mandarin bilinguals had a higher education level and higher occupation status than the Cantonese monolinguals. Mandarin monolinguals did not differ from Cantonese/Mandarin bilinguals significantly in years of education and occupation status. The multiple linear regression analyses indicated that Cantonese/Mandarin bilingualism can delay the onset of AD independently. Constantly speaking both Cantonese and Mandarin from at least early adulthood can delay the onset of AD. © 2018 S. Karger AG, Basel.

Small vessel disease, but neither amyloid load nor metabolic deficit, is dependent on age at onset in Alzheimer's disease.

PubMed

Ortner, Marion; Kurz, Alexander; Alexopoulos, Panagiotis; Auer, Florian; Diehl-Schmid, Janine; Drzezga, Alexander; Förster, Stefan; Förstl, Hans; Perneczky, Robert; Sorg, Christian; Yousefi, Behrooz H; Grimmer, Timo

2015-04-15

There is controversy concerning whether Alzheimer's disease (AD) with early onset is distinct from AD with late onset with regard to amyloid pathology and neuronal metabolic deficit. We hypothesized that compared with patients with early-onset AD, patients with late-onset AD have more comorbid small vessel disease (SVD) contributing to clinical severity, whereas there are no differences in amyloid pathology and neuronal metabolic deficit. The study included two groups of patients with probable AD dementia with evidence of the AD pathophysiologic process: 24 patients with age at onset <60 years old and 36 patients with age at onset >70 years old. Amyloid deposition was assessed using carbon-11-labeled Pittsburgh compound B positron emission tomography, comorbid SVD was assessed using magnetic resonance imaging, and neuronal metabolic deficit was assessed using fluorodeoxyglucose positron emission tomography. Group differences of global and regional distribution of pathology were explored using region of interest and voxel-based analyses, respectively, carefully controlling for the influence of dementia severity, apolipoprotein E genotype, and in particular SVD. The pattern of cognitive impairment was determined using z scores of the subtests of the Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological Assessment Battery. Patients with late-onset AD showed a significantly greater amount of SVD. No statistically significant differences in global or regional amyloid deposition or neuronal metabolic deficit between the two groups were revealed. However, when not controlling for SVD, subtle differences in fluorodeoxyglucose uptake between early-onset AD and late-onset AD groups were detectable. There were no significant differences regarding cognitive functioning. Age at onset does not influence amyloid deposition or neuronal metabolic deficit in AD. The greater extent of SVD in late-onset AD influences the association between neuronal metabolic

Early-Onset Alzheimer Disease and Candidate Risk Genes Involved in Endolysosomal Transport.

PubMed

Kunkle, Brian W; Vardarajan, Badri N; Naj, Adam C; Whitehead, Patrice L; Rolati, Sophie; Slifer, Susan; Carney, Regina M; Cuccaro, Michael L; Vance, Jeffery M; Gilbert, John R; Wang, Li-San; Farrer, Lindsay A; Reitz, Christiane; Haines, Jonathan L; Beecham, Gary W; Martin, Eden R; Schellenberg, Gerard D; Mayeux, Richard P; Pericak-Vance, Margaret A

2017-09-01

Mutations in APP, PSEN1, and PSEN2 lead to early-onset Alzheimer disease (EOAD) but account for only approximately 11% of EOAD overall, leaving most of the genetic risk for the most severe form of Alzheimer disease unexplained. This extreme phenotype likely harbors highly penetrant risk variants, making it primed for discovery of novel risk genes and pathways for AD. To search for rare variants contributing to the risk for EOAD. In this case-control study, whole-exome sequencing (WES) was performed in 51 non-Hispanic white (NHW) patients with EOAD (age at onset <65 years) and 19 Caribbean Hispanic families previously screened as negative for established APP, PSEN1, and PSEN2 causal variants. Participants were recruited from John P. Hussman Institute for Human Genomics, Case Western Reserve University, and Columbia University. Rare, deleterious, nonsynonymous, or loss-of-function variants were filtered to identify variants in known and suspected AD genes, variants in multiple unrelated NHW patients, variants present in 19 Hispanic EOAD WES families, and genes with variants in multiple unrelated NHW patients. These variants/genes were tested for association in an independent cohort of 1524 patients with EOAD, 7046 patients with late-onset AD (LOAD), and 7001 cognitively intact controls (age at examination, >65 years) from the Alzheimer's Disease Genetics Consortium. The study was conducted from January 21, 2013, to October 13, 2016. Alzheimer disease diagnosed according to standard National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer Disease and Related Disorders Association criteria. Association between Alzheimer disease and genetic variants and genes was measured using logistic regression and sequence kernel association test-optimal gene tests, respectively. Of the 1524 NHW patients with EOAD, 765 (50.2%) were women and mean (SD) age was 60.0 (4.9) years; of the 7046 NHW patients with LOAD, 4171 (59.2%) were women and mean

Canadian patient played key role in uncovering secrets about early-onset Alzheimer's disease.

PubMed Central

Lyttle, J

1996-01-01

Last June, the University of Toronto announced that Canadian scientists and a team of international researchers had discovered the gene responsible for most cases of early-onset Alzheimer's disease. One of the key players in that discovery had died just 3 months earlier. Frances Hodge, who participated in a battery of tests for the 20 years she lived with the disease, helped lead researchers to gene S182--and an ember of hope for future generations. Images p906-a PMID:8634971

Chromosome 17 and hereditary dementia: linkage studies in three non-Alzheimer families and kindreds with late-onset FAD.

PubMed

Bird, T D; Wijsman, E M; Nochlin, D; Leehey, M; Sumi, S M; Payami, H; Poorkaj, P; Nemens, E; Rafkind, M; Schellenberg, G D

1997-04-01

Several previous families with differing clinical and pathologic characteristics have demonstrated linkage to the 17q21-22 region. We have performed a linkage analysis with chromosome 17 markers on three families showing autosomal dominant inheritance of non-Alzheimer dementia and 60 kindreds with late-onset familial Alzheimer's disease (FAD). Family A shows unequivocal evidence of linkage with a maximum lod score of 5.0 for marker D17S934 (theta = 0.001). This family has an unusual syndrome of a schizophrenia-like psychosis beginning in the fifth or sixth decade followed by severe dementia with an average disease duration of 13.8 years. Neuropathology from five autopsies in this family has shown marked neurofibrillary tangle formation (NFT), degeneration of the amygdala, and no amyloid plaques. This confirms the presence of a gene associated with dementia on 17q and extends the related phenotype to include schizophrenia-like symptoms and classic NFT pathology. A second family with early aphasia progressing to dementia and cortical-basal ganglion-like degeneration also has suggestive evidence for linkage to 17q. A third family with very early-onset dementia (mean, 31 years) and nonspecific pathology can be excluded from the 17q region and emphasizes additional genetic heterogeneity in non-Alzheimer hereditary dementia. Finally, we also present evidence against linkage to D17S579 in the set of 60 families with late-onset FAD, providing further evidence that the chromosome 17 gene is unlikely to be involved in the pathogenesis of typical AD.

A novel presenilin 1 mutation (Ala275Val) as cause of early-onset familial Alzheimer disease.

PubMed

Luedecke, Daniel; Becktepe, Jos S; Lehmbeck, Jan T; Finckh, Ulrich; Yamamoto, Raina; Jahn, Holger; Boelmans, Kai

2014-04-30

Mutations in the presenilin 1 (PS1) gene (PSEN1) are associated with familial Alzheimer disease (FAD). Here, we report on a 50-year-old patient presenting with progressive deterioration of his short-term memory and a family history of early-onset dementia. Diagnostic workup included a neuropsychological examination, structural magnetic resonance (MR) imaging, cerebrospinal fluid (CSF) biomarkers including total tau, phosphorylated tau, and Aβ42 levels, as well as sequencing relevant fragments of the genes PSEN1, PSEN2, and APP. Additionally, we were able to obtain archival paraffin-embedded cerebellar tissue from the patient's father for cosegregation analysis. Clinical, neuropsychological and MR imaging data were indicative of early-onset Alzheimer disease. Furthermore, CSF biomarkers showed a typical pattern for Alzheimer disease. DNA sequencing revealed a heterozygous nucleotide transition (c.824C>T) in exon 8 of PSEN1, leading to an amino acid change from alanine to valine at codon 275 (Ala275Val). The same mutation was found in an archival brain specimen of the patient's demented father, but not in a blood sample of the non-demented mother. This mutation alters a conserved residue in the large hydrophilic loop of PS1, suggesting pathogenic relevance. Cosegregegation analysis and the structural as well as the presumed functional role of the mutated and highly conserved residue suggest FAD causing characteristics of the novel PSEN1 mutation Ala275Val. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Wild-type presenilin 1 protects against Alzheimer disease mutation-induced amyloid pathology.

PubMed

Wang, Runsheng; Wang, Baiping; He, Wanxia; Zheng, Hui

2006-06-02

Mutations in presenilin 1 (PS1) lead to dominant inheritance of early onset familial Alzheimer disease (FAD). These mutations are known to alter the gamma-secretase cleavage of the amyloid precursor protein, resulting in increased ratio of Abeta42/Abeta40 and accelerated amyloid plaque pathology in transgenic mouse models. To investigate the factors that drive the Abeta42/Abeta40 ratio and amyloid pathogenesis and to investigate the possible interactions between wild-type and FAD mutant PS1, which are co-expressed in transgenic animals, we expressed the PS1 M146V knock-in allele either on wild-type PS1 (PS1M146V/+) or PS1 null (PS1M146V/-) background and crossed these alleles with the Tg2576 APP transgenic mice. Introduction of the PS1 M146V mutation on Tg2576 background resulted in earlier onset of plaque pathology. Surprisingly, removing the wild-type PS1 in the presence of the PS1 M146V mutation (PS1M146V/-) greatly exacerbated the amyloid burden; and this was attributed to a reduction of gamma-secretase activity rather than an increase in Abeta42. Our findings establish a protective role of the wild-type PS1 against the FAD mutation-induced amyloid pathology through a partial loss-of-function mechanism.

Association of late-onset Alzheimer disease with a genotype of PLAU, the gene encoding urokinase-type plasminogen activator on chromosome 10q22.2.

PubMed

Finckh, U; van Hadeln, K; Müller-Thomsen, T; Alberici, A; Binetti, G; Hock, C; Nitsch, R M; Stoppe, G; Reiss, J; Gal, A

2003-08-01

Urokinase-type plasminogen activator (uPA) converts plasminogen to plasmin. Plasmin is involved in processing of amyloid precursor protein and degrades secreted and aggregated amyloid-beta, a hallmark of Alzheimer disease (AD). PLAU, the gene encoding uPA, maps to chromosome 10q22.2 between two regions showing linkage to late-onset AD (LOAD). We genotyped a frequent C/T single nucleotide polymorphism in codon 141 of PLAU (P141L) in 347 patients with LOAD and 291 control subjects. LOAD was associated with homozygous C/C PLAU genotype in the whole sample (chi2=15.7, P=0.00039, df 2), as well as in all sub-samples stratified by gender or APOE epsilon4 carrier status (chi2> or = 6.84, P< or =0.033, df 2). Odds ratio for LOAD due to homozygosity C/C was 1.89 (95% confidence interval 1.37-2.61). PLAU is a promising new candidate gene for LOAD, with allele C (P141) being a recessive risk allele or allele T (L141) conferring protection.

Screening of dementia genes by whole-exome sequencing in early-onset Alzheimer disease: input and lessons.

PubMed

Nicolas, Gaël; Wallon, David; Charbonnier, Camille; Quenez, Olivier; Rousseau, Stéphane; Richard, Anne-Claire; Rovelet-Lecrux, Anne; Coutant, Sophie; Le Guennec, Kilan; Bacq, Delphine; Garnier, Jean-Guillaume; Olaso, Robert; Boland, Anne; Meyer, Vincent; Deleuze, Jean-François; Munter, Hans Markus; Bourque, Guillaume; Auld, Daniel; Montpetit, Alexandre; Lathrop, Mark; Guyant-Maréchal, Lucie; Martinaud, Olivier; Pariente, Jérémie; Rollin-Sillaire, Adeline; Pasquier, Florence; Le Ber, Isabelle; Sarazin, Marie; Croisile, Bernard; Boutoleau-Bretonnière, Claire; Thomas-Antérion, Catherine; Paquet, Claire; Sauvée, Mathilde; Moreaud, Olivier; Gabelle, Audrey; Sellal, François; Ceccaldi, Mathieu; Chamard, Ludivine; Blanc, Frédéric; Frebourg, Thierry; Campion, Dominique; Hannequin, Didier

2016-05-01

Causative variants in APP, PSEN1 or PSEN2 account for a majority of cases of autosomal dominant early-onset Alzheimer disease (ADEOAD, onset before 65 years). Variant detection rates in other EOAD patients, that is, with family history of late-onset AD (LOAD) (and no incidence of EOAD) and sporadic cases might be much lower. We analyzed the genomes from 264 patients using whole-exome sequencing (WES) with high depth of coverage: 90 EOAD patients with family history of LOAD and no incidence of EOAD in the family and 174 patients with sporadic AD starting between 51 and 65 years. We found three PSEN1 and one PSEN2 causative, probably or possibly causative variants in four patients (1.5%). Given the absence of PSEN1, PSEN2 and APP causative variants, we investigated whether these 260 patients might be burdened with protein-modifying variants in 20 genes that were previously shown to cause other types of dementia when mutated. For this analysis, we included an additional set of 160 patients who were previously shown to be free of causative variants in PSEN1, PSEN2 and APP: 107 ADEOAD patients and 53 sporadic EOAD patients with an age of onset before 51 years. In these 420 patients, we detected no variant that might modify the function of the 20 dementia-causing genes. We conclude that EOAD patients with family history of LOAD and no incidence of EOAD in the family or patients with sporadic AD starting between 51 and 65 years have a low variant-detection rate in AD genes.

Reversible Pisa Syndrome Induced by Rivastigmine in a Patient With Early-Onset Alzheimer Disease.

PubMed

Hsu, Chih-Wei; Lee, Yu; Lee, Chun-Yi; Lin, Pao-Yen

Pisa syndrome (PS) is a state of dystonic muscle contraction with a marked truncal deviation to one side. It is an uncommon adverse effect of antipsychotic drugs, but is rarely reported in patients receiving acetylcholinesterase inhibitors, especially rivastigmine. We present a 57-year-old female patient with Alzheimer disease who began to develop symptoms of dementia at the age of 51 years. She was observed to have symptoms of PS after continuous use of rivastigmine (9 mg/d) for nearly 2 years. The PS symptoms improved after the dose of rivastigmine was reduced but recurred when the dose was added back to 9 mg/d. Finally, after we decreased the dose to 4.5 mg/d, her PS symptoms were remitted. This report reminds us that clinicians need to be cautious about the risk of PS when prescribing rivastigmine in a patient with early-onset Alzheimer disease.

Useful Information on...Alzheimer's Disease.

ERIC Educational Resources Information Center

Cohen, Gene D.

This brochure provides information on Alzheimer's disease by examining who gets Alzheimer's disease and what to expect when someone has Alzheimer's disease. Abnormal brain tissue findings are discussed and three clinical features of Alzheimer's disease are listed: dementia; insidious onset of symptoms; and exclusion of all other specific causes of…

Traumatic Brain Injury History is Associated with Earlier Age of Onset of Alzheimer Disease

PubMed Central

LoBue, Christian; Wadsworth, Hannah; Wilmoth, Kristin; Clem, Matthew; Hart, John; Womack, Kyle B.; Didehbani, Nyaz; Lacritz, Laura H.; Rossetti, Heidi C.; Cullum, C. Munro

2016-01-01

Objective This study examined whether a history of traumatic brain injury (TBI) is associated with earlier onset of Alzheimer disease (AD), independent of apolipoprotein ε4 status (Apoe4) and gender. Method Participants with a clinical diagnosis of AD (n=7625) were obtained from the National Alzheimer’s Coordinating Center Uniform Data Set, and categorized based on self-reported lifetime TBI with loss of consciousness (LOC) (TBI+ vs TBI-) and presence of Apoe4. ANCOVAs, controlling for gender, race, and education were used to examine the association between history of TBI, presence of Apoe4, and an interaction of both risk factors on estimated age of AD onset. Results Estimated AD onset differed by TBI history and Apoe4 independently (p’s <.001). The TBI+ group had a mean age of onset 2.5 years earlier than the TBI- group. Likewise, Apoe4 carriers had a mean age of onset 2.3 years earlier than non-carriers. While the interaction was non-significant (p = .34), participants having both a history of TBI and Apoe4 had the earliest mean age of onset compared to those with a TBI history or Apoe4 alone (MDifference = 2.8 & 2.7 years, respectively). These results remained unchanged when stratified by gender. Conclusions History of self-reported TBI can be associated with an earlier onset of AD-related cognitive decline, regardless of Apoe4 status and gender. TBI may be related to an underlying neurodegenerative process in AD, but the implications of age at time of injury, severity, and repetitive injuries remain unclear. PMID:27855547

Association Between Exercise Capacity and Late Onset of Dementia, Alzheimer Disease, and Cognitive Impairment.

PubMed

Müller, Jan; Chan, Khin; Myers, Jonathan N

2017-02-01

To address the association between exercise capacity and the onset of dementia, Alzheimer disease, and cognitive impairment. For 6104 consecutive veteran patients (mean ± SD age: 59.2±11.4 years) referred for treadmill exercise testing, the combined end point of dementia, Alzheimer disease, and cognitive impairment was abstracted from the Veterans Affairs computerized patient record system. After mean ± SD follow-up of 10.3±5.5 years, 353 patients (5.8%) developed the composite end point at a mean ± SD age of 76.7±10.3 years. After correction for confounders in multivariate Cox proportional hazards regression, higher age at exercise testing (hazard ratio [HR]=1.08; 95% CI, 1.07-1.09; P<.001), current smoking (HR=1.44; 95% CI, 1.08-1.93; P=.01), and exercise capacity (HR=0.92; 95% CI, 0.89-0.96; P<.001) emerged as predictors of cognitive impairment. Each 1-metabolic equivalent increase in exercise capacity conferred a nearly 8% reduction in the incidence of cognitive impairment. Meeting the recommendations for daily activity was not associated with a delay in onset of cognitive impairment (HR=1.07; 95% CI, 0.86-1.32; P=.55). Exercise capacity is strongly associated with cognitive function; the inverse association between fitness and cognitive impairment provides an additional impetus for health care providers to promote physical activity. Copyright © 2016 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

The Alzheimer's Prevention Initiative Generation Program: Evaluating CNP520 Efficacy in the Prevention of Alzheimer's Disease.

PubMed

Lopez Lopez, C; Caputo, A; Liu, F; Riviere, M E; Rouzade-Dominguez, M-L; Thomas, R G; Langbaum, J B; Lenz, R; Reiman, E M; Graf, A; Tariot, P N

2017-01-01

Alzheimer's disease pathology begins decades before the onset of clinical symptoms. This provides an opportunity for interventional clinical trials to potentially delay or prevent the onset of cognitive impairment or dementia. CNP520 (a beta-site-amyloid precursor protein-cleaving enzyme inhibitor) is in clinical development for the treatment of preclinical Alzheimer's disease under the Alzheimer's Prevention Initiative Generation Program. The Alzheimer's Prevention Initiative is a public-private partnership intended to accelerate the evaluation of Alzheimer's disease prevention therapies. The Generation Program comprises two pivotal phase II/III studies with similar designs to assess the efficacy and safety of investigational treatments in a cognitively unimpaired population at increased risk for developing Alzheimer's disease based on age and apolipoprotein E (APOE) genotype (i.e., presence of the APOE ε4 allele). The program has been designed to maximize benefit to Alzheimer's disease research. Generation Study 1 (NCT02565511) and Generation Study 2 (NCT03131453) are currently enrolling; their key features are presented here.

Young-onset Alzheimer dementia: a comparison of Brazilian and Norwegian carers' experiences and needs for assistance.

PubMed

Dourado, M C N; Laks, J; Kimura, N R; Baptista, M A T; Barca, M L; Engedal, K; Tveit, B; Johannessen, A

2018-06-01

Although dementia typically occurs in older people, it can also emerge in people aged younger than 65 years in the form of young-onset dementia, the most common type of which is Alzheimer's disease (AD). However, few studies have examined the needs of persons with young-onset AD (YO-AD) and their families, and cross-cultural research on the topic is even scarcer. In response, we investigated the situations, experiences and needs for assistance of carers of persons with YO-AD in Brazil and Norway. As part of our qualitative study, we formed a convenience sample of Brazilian (n = 9; 7 women) and Norwegian carers (n = 11; 6 women) in 2014 and 2015, respectively, and analysed data in light of a modified version of grounded theory. Carers' narratives from both countries revealed five common themes in terms of how YO-AD affected carers' psychological and emotional well-being, physical well-being, professional and financial well-being, social lives and need for support services. The infrequent differences between carers of persons with YO-AD in Brazil and Norway indicate that carers' problems are highly similar regardless of cultural differences and public services provided. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Potential late-onset Alzheimer's disease-associated mutations in the ADAM10 gene attenuate {alpha}-secretase activity.

PubMed

Kim, Minji; Suh, Jaehong; Romano, Donna; Truong, Mimy H; Mullin, Kristina; Hooli, Basavaraj; Norton, David; Tesco, Giuseppina; Elliott, Kathy; Wagner, Steven L; Moir, Robert D; Becker, K David; Tanzi, Rudolph E

2009-10-15

ADAM10, a member of a disintegrin and metalloprotease family, is an alpha-secretase capable of anti-amyloidogenic proteolysis of the amyloid precursor protein. Here, we present evidence for genetic association of ADAM10 with Alzheimer's disease (AD) as well as two rare potentially disease-associated non-synonymous mutations, Q170H and R181G, in the ADAM10 prodomain. These mutations were found in 11 of 16 affected individuals (average onset age 69.5 years) from seven late-onset AD families. Each mutation was also found in one unaffected subject implying incomplete penetrance. Functionally, both mutations significantly attenuated alpha-secretase activity of ADAM10 (>70% decrease), and elevated Abeta levels (1.5-3.5-fold) in cell-based studies. In summary, we provide the first evidence of ADAM10 as a candidate AD susceptibility gene, and report two potentially pathogenic mutations with incomplete penetrance for late-onset familial AD.

SORL1 variants and risk of late-onset Alzheimer's disease.

PubMed

Li, Yonghong; Rowland, Charles; Catanese, Joseph; Morris, John; Lovestone, Simon; O'Donovan, Michael C; Goate, Alison; Owen, Michael; Williams, Julie; Grupe, Andrew

2008-02-01

A recent study reported significant association of late-onset Alzheimer's disease (LOAD) with multiple single nucleotide polymorphisms (SNPs) and haplotypes in SORL1, a neuronal sortilin-related receptor protein known to be involved in the trafficking and processing of amyloid precursor protein. Here we attempted to validate this finding in three large, well characterized case-control series. Approximately 2000 samples from the three series were individually genotyped for 12 SNPs, including the 10 reported significant SNPs and 2 that constitute the reported significant haplotypes. A total of 25 allelic and haplotypic association tests were performed. One SNP rs2070045 was marginally replicated in the three sample sets combined (nominal P=0.035); however, this result does not remain significant when accounting for multiple comparisons. Further validation in other sample sets will be required to assess the true effects of SORL1 variants in LOAD.

Three SNPs in the GSTO1, GSTO2 and PRSS11 genes on chromosome 10 are not associated with age-at-onset of Alzheimer's disease.

PubMed

Ozturk, Ayla; Desai, Purnima P; Minster, Ryan L; Dekosky, Steven T; Kamboh, M Ilyas

2005-01-01

Linkage studies suggest the presence of putative risk and/or age-at-onset genes for Alzheimer's disease on Chromosome 10. Recently, a genomic converging approach using a combination of linkage, expression and association studies has reported significant associations of the glutathione S-transferase omega 1 and 2 (GSTO1 and GSTO2) genes and possibly the protease serine 11 (PRSS11) gene on chromosome 10 with age-at-onset, but not risk, for Alzheimer's disease (AD) and Parkinson disease. We investigated the association of the reported three polymorphisms in 990 sporadic late-onset AD cases (26% autopsy confirmed) and 735 controls. In our sample, we found no association either with age-at-onset in AD cases or with disease risk in the case-control cohort. However, haplotype analysis revealed a modest association of one haplotype with AD risk (p = 0.04). Additional markers in these genes need to be screened to explore their role in the etiology of AD.

Neuropsychological assessment and differential diagnosis in young-onset dementias.

PubMed

Sitek, Emilia J; Barczak, Anna; Harciarek, Michał

2015-06-01

Although Alzheimer's disease is the most common cause of dementia in the elderly, there are several conditions (ie, frontotemporal dementia or Huntington's disease) associated with a relatively earlier onset. This article provides arguments in favor of a comprehensive neuropsychological assessment in the differential diagnosis of young-onset dementia, as episodic memory impairment is not observed early in the course of most types of young-onset dementia that predominantly affect the domains of behavior, executive, language, and/or motor function. Copyright © 2015 Elsevier Inc. All rights reserved.

Age-specific incidence rates for dementia and Alzheimer disease in NIA-LOAD/NCRAD and EFIGA families: National Institute on Aging Genetics Initiative for Late-Onset Alzheimer Disease/National Cell Repository for Alzheimer Disease (NIA-LOAD/NCRAD) and Estudio Familiar de Influencia Genetica en Alzheimer (EFIGA).

PubMed

Vardarajan, Badri N; Faber, Kelley M; Bird, Thomas D; Bennett, David A; Rosenberg, Roger; Boeve, Bradley F; Graff-Radford, Neill R; Goate, Alison M; Farlow, Martin; Sweet, Robert A; Lantigua, Rafael; Medrano, Martin Z; Ottman, Ruth; Schaid, Daniel J; Foroud, Tatiana M; Mayeux, Richard

2014-03-01

Late-onset Alzheimer disease (LOAD), defined as onset of symptoms after age 65 years, is the most common form of dementia. Few reports investigate incidence rates in large family-based studies in which the participants were selected for family history of LOAD. To determine the incidence rates of dementia and LOAD in unaffected members in the National Institute on Aging Genetics Initiative for Late-Onset Alzheimer Disease/National Cell Repository for Alzheimer Disease (NIA-LOAD/NCRAD) and Estudio Familiar de Influencia Genetica en Alzheimer (EFIGA) family studies. Families with 2 or more affected siblings who had a clinical or pathological diagnosis of LOAD were recruited as a part of the NIA-LOAD/NCRAD Family Study. A cohort of Caribbean Hispanics with familial LOAD was recruited in a different study at the Taub Institute for Research on Alzheimer's Disease and the Aging Brain in New York and from clinics in the Dominican Republic as part of the EFIGA study. Age-specific incidence rates of LOAD were estimated in the unaffected family members in the NIA-LOAD/NCRAD and EFIGA data sets. We restricted analyses to families with follow-up and complete phenotype information, including 396 NIA-LOAD/NCRAD and 242 EFIGA families. Among the 943 at-risk family members in the NIA-LOAD/NCRAD families, 126 (13.4%) developed dementia, of whom 109 (86.5%) met criteria for LOAD. Among 683 at-risk family members in the EFIGA families, 174 (25.5%) developed dementia during the study period, of whom 145 (83.3%) had LOAD. The annual incidence rates of dementia and LOAD in the NIA-LOAD/NCRAD families per person-year were 0.03 and 0.03, respectively, in participants aged 65 to 74 years; 0.07 and 0.06, respectively, in those aged 75 to 84 years; and 0.08 and 0.07, respectively, in those 85 years or older. Incidence rates in the EFIGA families were slightly higher, at 0.03 and 0.02, 0.06 and 0.05, 0.10 and 0.08, and 0.10 and 0.07, respectively, in the same age groups. Contrasting these

Perceptions of stigma among people affected by early- and late-onset Alzheimer's disease.

PubMed

Ashworth, Rosalie

2017-07-01

The aim of this research was to explore perceptions of stigma among people with early- and late-onset Alzheimer's disease and those who support them, using questionnaires ( n = 44) and semi-structured interviews ( n = 14). Perceived stigma reporting was low in the questionnaires, whereas interviews revealed higher levels of perceived stigma in the form of unpredictable reactions to diagnosis, feeling stupid and ignorance of the condition among the public. Perceived stigma was managed in similar ways across age groups, focusing on 'being the lucky ones'. Results support the need to further tackle stigma and challenge expectations, particularly given the drive to diagnose people and thereby expose them to stigma.

Delaying the onset of Alzheimer disease: bilingualism as a form of cognitive reserve.

PubMed

Craik, Fergus I M; Bialystok, Ellen; Freedman, Morris

2010-11-09

There is strong epidemiologic evidence to suggest that older adults who maintain an active lifestyle in terms of social, mental, and physical engagement are protected to some degree against the onset of dementia. Such factors are said to contribute to cognitive reserve, which acts to compensate for the accumulation of amyloid and other brain pathologies. We present evidence that lifelong bilingualism is a further factor contributing to cognitive reserve. Data were collected from 211 consecutive patients diagnosed with probable Alzheimer disease (AD). Patients' age at onset of cognitive impairment was recorded, as was information on occupational history, education, and language history, including fluency in English and any other languages. Following this procedure, 102 patients were classified as bilingual and 109 as monolingual. We found that the bilingual patients had been diagnosed 4.3 years later and had reported the onset of symptoms 5.1 years later than the monolingual patients. The groups were equivalent on measures of cognitive and occupational level, there was no apparent effect of immigration status, and the monolingual patients had received more formal education. There were no gender differences. The present data confirm results from an earlier study, and thus we conclude that lifelong bilingualism confers protection against the onset of AD. The effect does not appear to be attributable to such possible confounding factors as education, occupational status, or immigration. Bilingualism thus appears to contribute to cognitive reserve, which acts to compensate for the effects of accumulated neuropathology.

Genetic heterogeneity and Alzheimer`s disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schellenberg, G.D.; Wijsman, E.M.; Bird, T.D.

1994-09-01

In some early-onset Alzheimer`s disease (AD) families, inheritance is autosomal dominant. (Early-onset AD is arbitarily defined as onset at {le} 60 years.) Two loci have been identified which are causative for early-onset familial AD (FAD). One is the amyloid precursor protein gene in which specific mutation have been identified. The second is a locus at 14q24.3 (AD3) which has been localized by linkage analysis; the gene and specific mutations have not been identified. Linkage studies place this locus between D14S61 and D14S63. These 2 loci, however, do not account for all early-onset FAD. The Volga German (VG) kindreds are descendantsmore » of families which emigrated from Germany to the Volga river region of Russia and subsequently to the US; AD in these families is hypothesized to be the result of a common genetic founder. The average age-at-onset in these families is 57 years. Linkage analysis for this group has been negative for the APP gene and for chromosome 14 markers. Thus, there is at least 1 other early-onset FAD locus. Recently, the {epsilon}4 allele of apolipoprotein E (ApoE) was identified as a risk-factor for late-onset AD. In a series of 53 late-onset kindreds, a strong genetic association was observed between the ApoE {epsilon}4 allele and AD. However, when linkage analysis was performed using a highly polymorphic locus at the ApoCII gene, which is within 30 kb of ApoE, significant evidence for co-segregation was not observed. This and other data suggests that while ApoE is an age-at-onset modifying locus, another gene(s), located elsewhere, contribute(s) to late-onset AD. Thus, there is probably at least 1 other late-onset locus. Once the VG locus is identified, it will be possible to determine whether an allelic variant of this locus is responsible for late-onset FAD.« less

Potential late-onset Alzheimer's disease-associated mutations in the ADAM10 gene attenuate α-secretase activity

PubMed Central

Kim, Minji; Suh, Jaehong; Romano, Donna; Truong, Mimy H.; Mullin, Kristina; Hooli, Basavaraj; Norton, David; Tesco, Giuseppina; Elliott, Kathy; Wagner, Steven L.; Moir, Robert D.; Becker, K. David; Tanzi, Rudolph E.

2009-01-01

ADAM10, a member of a disintegrin and metalloprotease family, is an α-secretase capable of anti-amyloidogenic proteolysis of the amyloid precursor protein. Here, we present evidence for genetic association of ADAM10 with Alzheimer's disease (AD) as well as two rare potentially disease-associated non-synonymous mutations, Q170H and R181G, in the ADAM10 prodomain. These mutations were found in 11 of 16 affected individuals (average onset age 69.5 years) from seven late-onset AD families. Each mutation was also found in one unaffected subject implying incomplete penetrance. Functionally, both mutations significantly attenuated α-secretase activity of ADAM10 (>70% decrease), and elevated Aβ levels (1.5–3.5-fold) in cell-based studies. In summary, we provide the first evidence of ADAM10 as a candidate AD susceptibility gene, and report two potentially pathogenic mutations with incomplete penetrance for late-onset familial AD. PMID:19608551

A Keto-Mediet Approach with Coconut Substitution and Exercise May Delay the Onset of Alzheimer's Disease among Middle-Aged.

PubMed

Perng, B C; Chen, M; Perng, J C; Jambazian, P

2017-01-01

Coconut oil has been widely used to improve health because there is much information available by word of mouth, in books, and on the internet. However, researchers still continue to search for the best diets to improve the quality of life, especially for people with cognitive decline. The aim of this review is to develop a novel dietary approach, the Keto-Mediet, which may help prevent the onset of Alzheimer's disease. Evidence gained through literature review from 1982 to 2015 on gene-by-diet interaction and lipid and glucose metabolism in the brains of Alzheimer's patients is converted into the new Keto-Mediet approach. The Keto-Mediet approach combines the benefits of a Ketogenic diet and a Mediterranean diet into a pyramidal model that is rich in various types of vitamins and substitutes coconuts for saturated animal fats. Limited glucose intake is intended to delay brain degeneration. A revised adult food pyramid was created to illustrate the principles of the Keto-Mediet approach. The Keto-Mediet approach represents and interprets food groups according to the revised adult food pyramid. This approach also encourages adherence to this healthy diet and lifestyle changes including exercise for people whose age ranges from 40 to 75 years. Those who comply with this approach will significantly enhance their knowledge and adopt a healthier lifestyle, as compared to those whose modern eating patterns are typically less healthy. Therefore, the Keto-Mediet approach can be applied in hopes of preventing and decreasing Alzheimer's disease in different ethnicities and cultural groups.

Novel PSEN1 G209A mutation in early-onset Alzheimer dementia supported by structural prediction.

PubMed

An, Seong Soo A; Bagyinszky, Eva; Kim, Hye Ryoun; Seok, Ju-Won; Shin, Hae-Won; Bae, SeunOh; Kim, SangYun; Youn, Young Chul

2016-05-20

Three main genes are described as causative genes for early-onset Alzheimer dementia (EOAD): APP, PSEN1 and PSEN2. We describe a woman with EOAD had a novel PSEN1 mutation. A 54-year-old right-handed woman presented 12-year history of progressive memory decline. She was clinically diagnosed as familial Alzheimer's disease due to a PSEN1 mutation. One of two daughters also has the same mutation, G209A in the TM-IV of PS1 protein. Her mother had unspecified dementia that began at the age of 40s. PolyPhen2 and SIFT prediction suggested that G209A might be a damaging variant with high scores. 3D modeling revealed that G209A exchange could result significant changes in the PS1 protein. We report a case of EOAD having probable novel PSEN1 (G209A) mutation verified with structural prediction.

No Association Between CALHM1 Variation and Risk of Alzheimer Disease

PubMed Central

Minster, Ryan L.; Demirci, F. Yesim; DeKosky, Steven T.; Kamboh, M. Ilyas

2010-01-01

A polymorphism in the calcium homeostasis modulator 1 gene (CALHM1) has recently been associated with risk of late-onset Alzheimer disease. We examined this variant (rs2986017) in 945 Caucasian Americans with late-onset Alzheimer disease and 875 age-matched Caucasian American controls. No association with risk of late-onset Alzheimer disease (p = 0.368 for genotypes; p = 0.796 for alleles) was observed in our sample. However, a potential modest association of minor allele homozygosity (TT) with an earlier age-at-onset was seen (p = 0.034). PMID:19191331

No association between CALHM1 variation and risk of Alzheimer disease.

PubMed

Minster, Ryan L; Demirci, F Yesim; DeKosky, Steven T; Kamboh, M Ilyas

2009-04-01

A polymorphism in the calcium homeostasis modulator 1 gene (CALHM1) has recently been associated with risk of late-onset Alzheimer disease. We examined this variant (rs2986017) in 945 Caucasian Americans with late-onset Alzheimer disease and 875 age-matched Caucasian American controls. No association with risk of late-onset Alzheimer disease (p=0.368 for genotypes; p=0.796 for alleles) was observed in our sample. However, a potential modest association of minor allele homozygosity (TT) with an earlier age-at-onset was seen (p=0.034). (c) 2009 Wiley-Liss, Inc.

Genome-wide association analysis of age-at-onset in Alzheimer's disease.

PubMed

Kamboh, M I; Barmada, M M; Demirci, F Y; Minster, R L; Carrasquillo, M M; Pankratz, V S; Younkin, S G; Saykin, A J; Sweet, R A; Feingold, E; DeKosky, S T; Lopez, O L

2012-12-01

The risk of Alzheimer's disease (AD) is strongly determined by genetic factors and recent genome-wide association studies (GWAS) have identified several genes for the disease risk. In addition to the disease risk, age-at-onset (AAO) of AD has also strong genetic component with an estimated heritability of 42%. Identification of AAO genes may help to understand the biological mechanisms that regulate the onset of the disease. Here we report the first GWAS focused on identifying genes for the AAO of AD. We performed a genome-wide meta-analysis on three samples comprising a total of 2222 AD cases. A total of ~2.5 million directly genotyped or imputed single-nucleotide polymorphisms (SNPs) were analyzed in relation to AAO of AD. As expected, the most significant associations were observed in the apolipoprotein E (APOE) region on chromosome 19 where several SNPs surpassed the conservative genome-wide significant threshold (P<5E-08). The most significant SNP outside the APOE region was located in the DCHS2 gene on chromosome 4q31.3 (rs1466662; P=4.95E-07). There were 19 additional significant SNPs in this region at P<1E-04 and the DCHS2 gene is expressed in the cerebral cortex and thus is a potential candidate for affecting AAO in AD. These findings need to be confirmed in additional well-powered samples.

Case Studies Illustrating Focal Alzheimer's, Fluent Aphasia, Late-Onset Memory Loss, and Rapid Dementia.

PubMed

Camsari, Gamze Balci; Murray, Melissa E; Graff-Radford, Neill R

2016-08-01

Many dementia subtypes have more shared signs and symptoms than defining ones. We review 8 cases with 4 overlapping syndromes and demonstrate how to distinguish the cases. These include focal cortical presentations of Alzheimer's disease (AD; posterior cortical atrophy and corticobasal syndrome [CBS]), fluent aphasia (semantic dementia and logopenic aphasia), late-onset slowly progressive dementia (hippocampal sclerosis and limbic predominant AD) and rapidly progressive dementia (Creutzfeldt-Jakob disease and limbic encephalitis). Recognizing the different syndromes can help the clinician to improve their diagnostic skills, leading to improved patient outcomes by early and accurate diagnosis, prompt treatment, and appropriate counseling and guidance. Copyright © 2016 Elsevier Inc. All rights reserved.

Variability of age at onset in siblings with familial Alzheimer disease.

PubMed

Gómez-Tortosa, Estrella; Barquero, M Sagrario; Barón, Manuel; Sainz, M Jose; Manzano, Sagrario; Payno, Maria; Ros, Raquel; Almaraz, Carmen; Gómez-Garré, Pilar; Jiménez-Escrig, Adriano

2007-12-01

Variability of age at onset (AO) of Alzheimer disease (AD) among members of the same family is important as a biological clue and because of its clinical effects. To evaluate which clinical variables influence the discrepancy in AO among affected relatives with familial AD. Clinical genetic project of Spanish kindred with AD conducted by 4 academic hospitals in Madrid, Spain. Age at onset of AD in 162 families and discrepancy in AO in intragenerational and intergenerational affected pairs were analyzed in relation to age, sex, maternal or paternal transmission, pattern of inheritance, and apolipoprotein E genotype. Maternal transmission of AD was significantly more frequent than paternal transmission (P < .001). In 27% of the affected individuals, AO occurred before the patient was 65 years old. Discrepancy in AO among siblings was within 5 years in 44% of the families, 6 to 10 years in 29%, and more than 10 years in 27% (range, 0-22). This discrepancy was independent of the sex of the sibling pairs and was significantly lower with maternal transmission of AD (P = .02). Segregation analysis showed no differences in the inheritance pattern between families with low (< or =5 years) or high (>5 years) AO discrepancy. Age at onset in carriers of the apolipoprotein E epsilon4 allele was slightly younger. However, among siblings, an extra apolipoprotein E epsilon4 allele was not consistently associated with earlier onset of AD. Eighty percent of patients, independent of sex or mode of transmission, were already affected at their parents' reported AO. There is a wide discrepancy in AO in affected siblings that is not clearly explained by a single clinical variable or apolipoprotein E genotype. The interaction of many factors probably determines AO in each affected individual. However, maternal transmission of AD seems to result in a similar AO in offspring, and the risk of developing dementia after the parent's reported AO decreases significantly.

Genetic Ancestry and Susceptibility to Late-Onset Alzheimer Disease (LOAD) in the Admixed Colombian Population.

PubMed

Moreno, Diana J; Pino, Sebastián; Ríos, Ángela; Lopera, Francisco; Ostos, Henry; Via, Marc; Bedoya, Gabriel

2017-01-01

Differences in the prevalence of dementia among populations and in the effect of apolipoprotein E (APOE) on the emergence of Alzheimer disease (AD), which is the main type of dementia, have been reported. This study estimated the ancestry of a group of individuals with late-onset Alzheimer disease (LOAD) (N=280) and established whether there were any differences when compared with a control group (N=357) in a sample of the Colombian population. When the analyses were adjusted for known risk factors such as age, sex, presence of APOE[Latin Small Letter Open E]4, socioeconomic status, educational attainment, and place of birth, African ancestry was associated with an increased LOAD risk (odds ratio: 1.55; 95% confidence interval, 1.09-2.03; P=0.029), whereas Native American ancestry was associated with lower risk (odds ratio: 0.75; 95% confidence interval, 0.61-0.98; P=0.046), for every 10% increase in ancestry. In addition, there were significant differences in the proportion of Native American ancestry between carriers and noncarriers of the APOE[Latin Small Letter Open E]4 allele (Mann-Whitney U test, P=0.047), with noncarriers having higher mean Native American ancestry when compared with carriers. Our results are consistent with the presence of variants of African origin in the genome of the Colombian population and different from APOE[Latin Small Letter Open E]4 that represents a risk factor for the development of LOAD, whereas variants of Native American origin may be conferring protection. However, unknown environmental factors or epigenetic differences among continental groups could also explain the observed associations.

Role of familial factors in late-onset Alzheimer disease as a function of age.

PubMed

Wu, Z; Kinslow, C; Pettigrew, K D; Rapoport, S I; Schapiro, M B

1998-09-01

Whereas early-onset Alzheimer disease (AD; usually onset at age < 50 years) has been defined with genetic mutation on chromosomes 1, 14, and 21, the degree of familial contribution to late-onset AD is unclear. Further, it is uncertain if subgroups of late-onset AD exist. To examine the influence of familial factors as a function of age in late-onset AD we investigated lifetime risks and age-specific hazard rates of AD-like illness among late-onset AD probands' and controls' first-degree relatives, using questionnaires and medical records. As part of a longitudinal study on aging and AD, we studied 78 AD probands with age of onset > or =50 years (28 "definite" and 50 "probable" AD according to NINCDS/ADRDA criteria) and 101 healthy old controls seen since 1981. Both probands and controls were screened rigorously with medical tests and brain imaging and seen regularly until autopsy. Multiple informants and medical records were used for first-degree relatives. Among first-degree relatives, 49 secondary cases of AD-like illness were found for the AD probands' relatives (391 relatives 40 years old or older) compared with 20 cases among controls' relatives (456 relatives 40 years old or older). Relatives of AD probands had a significantly increased lifetime risk of AD-like illness of 52.8+/-11.4% by age 94 years compared with a lifetime risk in relatives of controls of 22.1+/-5.8% by age 90 years. Age-specific hazard rates in relatives of AD probands increased until the 75-79-year age interval and then decreased; in contrast the age-specific hazard rates increased in relatives of controls after the 80-84-year age interval. To determine if a dividing line exist among late-onset AD, several cutoff ages were used in our study to compare cumulative risk curves of AD-like illness between relatives of late-onset probands and relatives of late-late-onset probands. Differences in the pattern of cumulative incidence of AD in relatives showed that 67-71 years is the range for a

Discovery of gene-gene interactions across multiple independent data sets of late onset Alzheimer disease from the Alzheimer Disease Genetics Consortium.

PubMed

Hohman, Timothy J; Bush, William S; Jiang, Lan; Brown-Gentry, Kristin D; Torstenson, Eric S; Dudek, Scott M; Mukherjee, Shubhabrata; Naj, Adam; Kunkle, Brian W; Ritchie, Marylyn D; Martin, Eden R; Schellenberg, Gerard D; Mayeux, Richard; Farrer, Lindsay A; Pericak-Vance, Margaret A; Haines, Jonathan L; Thornton-Wells, Tricia A

2016-02-01

Late-onset Alzheimer disease (AD) has a complex genetic etiology, involving locus heterogeneity, polygenic inheritance, and gene-gene interactions; however, the investigation of interactions in recent genome-wide association studies has been limited. We used a biological knowledge-driven approach to evaluate gene-gene interactions for consistency across 13 data sets from the Alzheimer Disease Genetics Consortium. Fifteen single nucleotide polymorphism (SNP)-SNP pairs within 3 gene-gene combinations were identified: SIRT1 × ABCB1, PSAP × PEBP4, and GRIN2B × ADRA1A. In addition, we extend a previously identified interaction from an endophenotype analysis between RYR3 × CACNA1C. Finally, post hoc gene expression analyses of the implicated SNPs further implicate SIRT1 and ABCB1, and implicate CDH23 which was most recently identified as an AD risk locus in an epigenetic analysis of AD. The observed interactions in this article highlight ways in which genotypic variation related to disease may depend on the genetic context in which it occurs. Further, our results highlight the utility of evaluating genetic interactions to explain additional variance in AD risk and identify novel molecular mechanisms of AD pathogenesis. Copyright © 2016 Elsevier Inc. All rights reserved.

Variants in the ATP-Binding Cassette Transporter (ABCA7), Apolipoprotein E ε4, and the Risk of Late-Onset Alzheimer Disease in African Americans

PubMed Central

Reitz, Christiane; Jun, Gyungah; Naj, Adam; Rajbhandary, Ruchita; Vardarajan, Badri Narayan; Wang, Li-San; Valladares, Otto; Lin, Chiao-Feng; Larson, Eric B.; Graff-Radford, Neill R.; Evans, Denis; De Jager, Philip L.; Crane, Paul K.; Buxbaum, Joseph D.; Murrell, Jill R.; Raj, Towfique; Ertekin-Taner, Nilufer; Logue, Mark; Baldwin, Clinton T.; Green, Robert C.; Barnes, Lisa L.; Cantwell, Laura B.; Fallin, M. Daniele; Go, Rodney C. P.; Griffith, Patrick; Obisesan, Thomas O.; Manly, Jennifer J.; Lunetta, Kathryn L.; Kamboh, M. Ilyas; Lopez, Oscar L.; Bennett, David A.; Hendrie, Hugh; Hall, Kathleen S.; Goate, Alison M.; Byrd, Goldie S.; Kukull, Walter A.; Foroud, Tatiana M.; Haines, Jonathan L.; Farrer, Lindsay A.; Pericak-Vance, Margaret A.; Schellenberg, Gerard D.; Mayeux, Richard

2013-01-01

Importance Genetic variants associated with susceptibility to late-onset Alzheimer disease are known for individuals of European ancestry, but whether the same or different variants account for the genetic risk of Alzheimer disease in African American individuals is unknown. Identification of disease-associated variants helps identify targets for genetic testing, prevention, and treatment. Objective To identify genetic loci associated with late-onset Alzheimer disease in African Americans. Design, Setting, and Participants The Alzheimer Disease Genetics Consortium (ADGC) assembled multiple data sets representing a total of 5896 African Americans (1968 case participants, 3928 control participants) 60 years or older that were collected between 1989 and 2011 at multiple sites. The association of Alzheimer disease with genotyped and imputed single-nucleotide polymorphisms (SNPs) was assessed in case-control and in family-based data sets. Results from individual data sets were combined to perform an inverse variance–weighted meta-analysis, first with genome-wide analyses and subsequently with gene-based tests for previously reported loci. Main Outcomes and Measures Presence of Alzheimer disease according to standardized criteria. Results Genome-wide significance in fully adjusted models (sex, age, APOE genotype, population stratification) was observed for a SNP in ABCA7 (rs115550680, allele = G; frequency, 0.09 cases and 0.06 controls; odds ratio [OR], 1.79 [95% CI, 1.47-2.12]; P = 2.2 × 10–9), which is in linkage disequilibrium with SNPs previously associated with Alzheimer disease in Europeans (0.8Alzheimer disease but not reaching significance in genome-wide analyses were replicated in gene-based analyses

Variants in the ATP-binding cassette transporter (ABCA7), apolipoprotein E ϵ4,and the risk of late-onset Alzheimer disease in African Americans.

PubMed

Reitz, Christiane; Jun, Gyungah; Naj, Adam; Rajbhandary, Ruchita; Vardarajan, Badri Narayan; Wang, Li-San; Valladares, Otto; Lin, Chiao-Feng; Larson, Eric B; Graff-Radford, Neill R; Evans, Denis; De Jager, Philip L; Crane, Paul K; Buxbaum, Joseph D; Murrell, Jill R; Raj, Towfique; Ertekin-Taner, Nilufer; Logue, Mark; Baldwin, Clinton T; Green, Robert C; Barnes, Lisa L; Cantwell, Laura B; Fallin, M Daniele; Go, Rodney C P; Griffith, Patrick; Obisesan, Thomas O; Manly, Jennifer J; Lunetta, Kathryn L; Kamboh, M Ilyas; Lopez, Oscar L; Bennett, David A; Hendrie, Hugh; Hall, Kathleen S; Goate, Alison M; Byrd, Goldie S; Kukull, Walter A; Foroud, Tatiana M; Haines, Jonathan L; Farrer, Lindsay A; Pericak-Vance, Margaret A; Schellenberg, Gerard D; Mayeux, Richard

2013-04-10

Genetic variants associated with susceptibility to late-onset Alzheimer disease are known for individuals of European ancestry, but whether the same or different variants account for the genetic risk of Alzheimer disease in African American individuals is unknown. Identification of disease-associated variants helps identify targets for genetic testing, prevention, and treatment. To identify genetic loci associated with late-onset Alzheimer disease in African Americans. The Alzheimer Disease Genetics Consortium (ADGC) assembled multiple data sets representing a total of 5896 African Americans (1968 case participants, 3928 control participants) 60 years or older that were collected between 1989 and 2011 at multiple sites. The association of Alzheimer disease with genotyped and imputed single-nucleotide polymorphisms (SNPs) was assessed in case-control and in family-based data sets. Results from individual data sets were combined to perform an inverse variance-weighted meta-analysis, first with genome-wide analyses and subsequently with gene-based tests for previously reported loci. Presence of Alzheimer disease according to standardized criteria. Genome-wide significance in fully adjusted models (sex, age, APOE genotype, population stratification) was observed for a SNP in ABCA7 (rs115550680, allele = G; frequency, 0.09 cases and 0.06 controls; odds ratio [OR], 1.79 [95% CI, 1.47-2.12]; P = 2.2 × 10(-9)), which is in linkage disequilibrium with SNPs previously associated with Alzheimer disease in Europeans (0.8 < D' < 0.9). The effect size for the SNP in ABCA7 was comparable with that of the APOE ϵ4-determining SNP rs429358 (allele = C; frequency, 0.30 cases and 0.18 controls; OR, 2.31 [95% CI, 2.19-2.42]; P = 5.5 × 10(-47)). Several loci previously associated with Alzheimer disease but not reaching significance in genome-wide analyses were replicated in gene-based analyses accounting for linkage disequilibrium between markers and correcting for number of tests

Inflammatory signaling in Alzheimer disease and depression.

PubMed

Barber, Robert

2011-08-01

To help define the relationships among inflammation, Alzheimer disease, and depression, the Texas Alzheimer's Research Consortium analyzed an array of inflammatory biomarkers in a cohort of patients with Alzheimer disease and in controls. Inflammation severity was highly correlated with earlier age at onset of Alzheimer disease and was also associated with cognitive decline. The relationship between inflammation and depression was not as clear, and it varied with aspects of depression, gender, and the presence of Alzheimer disease.

Ameliorating effect of anti-Alzheimer's drugs on the bidirectional association between type 2 diabetes mellitus and Alzheimer's disease.

PubMed

Ahmed, Amira S; Elgharabawy, Rehab M; Al-Najjar, Amal H

2017-07-01

Mild to severe forms of nervous system damage were exhibited by approximately 60-70% of diabetics. It is important to understand the association between type 2 diabetes mellitus and Alzheimer's disease. The aim of the present work is to understand the bidirectional association between type 2 diabetes and Alzheimer's disease pathogenesis, that was monitored by glycaemic status, lipid profile, amyloid beta 40 and 42 (Aβ40 and Aβ42), C-reactive protein, total creatine kinase, total lactate dehydrogenase, D-dimer and magnesium measurements, to assess the association between theses biochemical markers and each other, to estimate the possibility of utilizing the amyloid beta as biochemical marker of T2D in Alzheimer's patients, and to evaluate the effect of piracetam and memantine drugs on diabetes mellitus. This study involved 120 subjects divided into 20 healthy control (group I), 20 diabetic patients (group II), 20 Alzheimer's patients (group III), 20 diabetic Alzheimer's patients with symptomatic treatment (group IV), 20 diabetic Alzheimer's patients treated with memantine (group V), and 20 diabetic Alzheimer's patients treated with piracetam (group VI). The demographic characteristics, diabetic index, and lipid profile were monitored. Plasma amyloid beta 40 and amyloid beta 42, C-reactive protein, total creatine kinase, total lactate dehydrogenase, D-dimer, and magnesium were assayed. The levels of amyloid beta 40 and amyloid beta 42 were significantly elevated in diabetic Alzheimer's patients with symptomatic treatment (group IV) compared to group II (by 50.5 and 7.5 fold, respectively) and group III (by 25.4 and 2.8 fold, respectively). In groups II, III, IV, V and VI, significant and positive associations were monitored between insulin and amyloid beta 40, amyloid beta 42, C-reactive protein, total creatine kinase, and D-dimer. Diabetic markers were significantly decreased in diabetic Alzheimer's patients treated with anti-Alzheimer's drugs (especially

Elevated galanin may predict the risk of type 2 diabetes mellitus for development of Alzheimer's disease.

PubMed

Zhang, Zhenwen; Fang, Penghua; Shi, Mingyi; Zhu, Yan; Bo, Ping

2015-09-01

Alzheimer's disease is the most common form of dementia among the elderly and is characterized by progressive loss of memory and cognition. Epidemiological and clinical studies demonstrated that type 2 diabetes mellitus is an important risk factor for the development of Alzheimer's disease, i.e., the patients with type 2 diabetes mellitus are frequently companied with Alzheimer's disease symptoms. Despite many studies recently probed into the comorbid state of both diseases, so far the precise mechanism for this association is poorly understood. Emerging evidences suggest that defects in galanin play a central role on type 2 diabetes mellitus and is considered to be a risk factor for Alzheimer's disease development. This review provides a new insight into the multivariate relationship among galanin, type 2 diabetes mellitus and Alzheimer's disease, highlighting the effect of galanin system on the cross-talk between both diseases in human and rodent models. The current data support that activating central GalR2 attenuates insulin resistance and Alzheimer's disease feature in animal models. These may help us better understanding the pathogenesis of both diseases and provide useful hints for the development of novel therapeutic approaches to treat type 2 diabetes mellitus and Alzheimer's disease. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

The genetics of Alzheimer disease: current status and future prospects.

PubMed

Blacker, D; Tanzi, R E

1998-03-01

Four genes involved in the development of Alzheimer disease have been identified. Three fully penetrant (deterministic) genes lead to the development of Alzheimer disease in patients younger than 60 years: the amyloid beta-protein precursor on chromosome 21, presenilin 1 on chromosome 14, and presenilin 2 on chromosome 1. Together, they account for about half of this early-onset form of the disease. One genetic risk factor--apolipoprotein E-4--is associated with late-onset Alzheimer disease. It accounts for a substantial fraction of disease burden but seems to act primarily to lower the age of disease onset. In general, none of these genes can be easily adapted for use as a diagnostic or predictive test for Alzheimer disease. Research activity includes searching for additional genes, especially for late-onset disease, and elucidating the mechanism of action of all identified genes as part of a long-term effort to develop more effective therapeutic and preventive strategies.

Elucidating Pathogenic Mechanisms of Early-onset Alzheimer's Disease in Down Syndrome Patients.

PubMed

Asai, Masashi; Kawakubo, Takashi; Mori, Ryotaro; Iwata, Nobuhisa

2017-01-01

Down syndrome (DS) patients demonstrate the neuropathology of Alzheimer's disease (AD) characterized by the formation of senile plaques and neurofibrillary tangles by age 40-50 years. It has been considered for a number of years that 1.5-fold expression of the gene for the amyloid precursor protein (APP) located on chromosome 21 leading to overproduction of amyloid-β peptide (Aβ) results in the early onset of AD in adults with DS. However, the mean age of onset of familial AD with the Swedish mutation on APP which has high affinity for β-secretase associated with a dramatic increase in Aβ production is about 55 years. This paradox indicates that there is a poor correlation between average ages of AD onset and the theoretical amount of Aβ production and that there are factors exacerbating AD on chromosome 21. We therefore focused on dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A), since overexpressing transgenic mice show AD-like brain pathology. The overexpression of DYRK1A caused suppression of the activity of neprilysin (NEP), which is a major Aβ-degrading enzyme in the brain, and phosphorylation at the NEP cytoplasmic domain. NEP activity was markedly reduced in fibroblasts derived from DS patients compared with that in fibroblasts derived from healthy controls. This impaired activity of NEP was rescued by DYRK1A inhibition. These results show that DYRK1A overexpression causes suppression of NEP activity through its phosphorylation in DS patients. Our results suggest that DYRK1A inhibitors could be effective against AD not only in adults with DS but also in sporadic AD patients.

Case-control study of dementia of the Alzheimer type

DOE Office of Scientific and Technical Information (OSTI.GOV)

French, L.R.; Schuman, L.M.; Mortimer, J.A.

1985-03-01

A case-control study to assess factors of possible etiologic significance to dementia of the Alzheimer type was conducted with 78 male cases diagnosed in 1979-1982 at the Veterans Administration Medical Center in Minneapolis, Minnesota and age-race-sex-matched hospital and neighborhood controls (14 of 16 autopsied cases were histopathologically confirmed). Information was obtained on variables relevant to vital, genetic, and immunologic hypotheses, and on possible occupational and environmental exposures, drug use, psychologic stress, smoking, and alcohol consumption. The only major difference between patients with dementia of the Alzheimer type and controls was a significantly greater occurrence of antecedent head trauma in themore » patients (odds ratio = 4.50). This finding is consistent with the literature on posttraumatic dementia but its importance is presently unclear.« less

Late-onset Alzheimer's risk variants in memory decline, incident mild cognitive impairment, and Alzheimer's disease.

PubMed

Carrasquillo, Minerva M; Crook, Julia E; Pedraza, Otto; Thomas, Colleen S; Pankratz, V Shane; Allen, Mariet; Nguyen, Thuy; Malphrus, Kimberly G; Ma, Li; Bisceglio, Gina D; Roberts, Rosebud O; Lucas, John A; Smith, Glenn E; Ivnik, Robert J; Machulda, Mary M; Graff-Radford, Neill R; Petersen, Ronald C; Younkin, Steven G; Ertekin-Taner, Nilüfer

2015-01-01

We tested association of nine late-onset Alzheimer's disease (LOAD) risk variants from genome-wide association studies (GWAS) with memory and progression to mild cognitive impairment (MCI) or LOAD (MCI/LOAD) in older Caucasians, cognitively normal at baseline and longitudinally evaluated at Mayo Clinic Rochester and Jacksonville (n>2000). Each variant was tested both individually and collectively using a weighted risk score. APOE-e4 associated with worse baseline memory and increased decline with highly significant overall effect on memory. CLU-rs11136000-G associated with worse baseline memory and incident MCI/LOAD. MS4A6A-rs610932-C associated with increased incident MCI/LOAD and suggestively with lower baseline memory. ABCA7-rs3764650-C and EPHA1-rs11767557-A associated with increased rates of memory decline in subjects with a final diagnosis of MCI/LOAD. PICALM-rs3851179-G had an unexpected protective effect on incident MCI/LOAD. Only APOE-inclusive risk scores associated with worse memory and incident MCI/LOAD. The collective influence of the nine top LOAD GWAS variants on memory decline and progression to MCI/LOAD appears limited. Discovery of biologically functional variants at these loci may uncover stronger effects on memory and incident disease. Copyright © 2015 Elsevier Inc. All rights reserved.

Association between the APOE ε4 Allele and Late-Onset Alzheimer's Disease in an Ecuadorian Mestizo Population

PubMed Central

Calero, Cristian; Vinueza, Rodrigo; Correa, Patricio; Carrera-Gonzalez, Andrea; Villegas, Franklin; Moreta, Germania; Paredes, Rosario

2017-01-01

Alzheimer's disease (AD) is the most common neurodegenerative disease. It has two main pathological hallmarks: amyloid plaques and neurofibrillary tangles. The APOE ε4 allele has been recognized as the strongest genetic risk factor for late-onset Alzheimer's disease (LOAD) in several populations worldwide, yet the risk varies by region and ethnicity. The aims of this study were to describe APOE allele and genotype frequencies and examine the relationship between the APOE ε4 allele and LOAD risk in an Ecuadorian Mestizo population. We carried out a case-control study comprising 56 individuals clinically diagnosed with probable AD (≥65 years of age) and 58 unrelated healthy control subjects (≥65 years of age). Genotyping was performed using the real-time PCR method. Our data showed that allelic and genotypic frequencies follow the trends observed in most worldwide populations. We also found a high-risk association between APOE ε4 allele carriers and LOAD (OR = 7.286; 95% CI = 2.824–18.799; p < 0.001). Therefore, we concluded that APOE ε4 must be considered an important genetic risk factor for LOAD in the Ecuadorian Mestizo population. Additionally, we suggest that in mixed populations the effects of admixture and ethnic identity should be differentiated when evaluating genetic contributions to Alzheimer's disease risk. PMID:29348964

A variant of the sigma receptor type-1 gene is a protective factor for Alzheimer disease.

PubMed

Uchida, Naohiko; Ujike, Hiroshi; Tanaka, Yuji; Sakai, Ayumu; Yamamoto, Mitsutoshi; Fujisawa, Yoshikatsu; Kanzaki, Akihiro; Kuroda, Shigetoshi

2005-12-01

Some preclinical evidence suggests that the sigma receptor type 1, which plays several roles in learning and memory, may also be involved in the pathogenesis of Alzheimer disease (AD). The authors provide here genetic evidence that the sigma receptor type 1 (SIGMAR1) gene is involved in susceptibility to AD. Two polymorphisms of the SIGMAR1 gene, G-241T/C-240T and Q2P, were analyzed in a Japanese sample of 239 patients with AD and 227 comparisons subjects. These two polymorphisms were in complete linkage disequilibrium with each other, resulting in only two haplotypes, GC-241-240Q2 and TT-241-240P2. There was a significant association between AD and the TT-241-240P2 haplotype of the SIGMAR1 gene and its homozygote, found with late-onset, but not early-onset AD. After stratification by epsilon4 allele status of the apolipoprotein E gene, TT-241-240P2 homozygosity of the SIGMAR1 gene reduced the risk of AD in epsilon4 allele carriers by three-fourths. The present study suggests that the TT-241-240P2 haplotype of the SIGMAR1 gene, which decreases expression of the gene, may have a protective role against susceptibility to AD.

Chromosome-12 mapping of late-onset Alzheimer disease among Caribbean Hispanics.

PubMed

Mayeux, R; Lee, J H; Romas, S N; Mayo, D; Santana, V; Williamson, J; Ciappa, A; Rondon, H Z; Estevez, P; Lantigua, R; Medrano, M; Torres, M; Stern, Y; Tycko, B; Knowles, J A

2002-01-01

Linkage to chromosome 12p for familial Alzheimer disease (AD) has been inconsistent. Using 35 markers near the centromere of chromosome 12, we investigated 79 Caribbean Hispanic families with AD. Two-point linkage analysis using affected sib pairs yielded LOD scores of 3.15 at D12S1623 and 1.43 at D12S1042. The LOD score at D12S1623 decreased to 1.62 in families with late-onset (age >65 years) AD (LOAD), but the LOD score at D12S1042 was unchanged. Among families negative for the apolipoprotein E (APOE-epsilon 4) allele, the LOD score for D12S1623 was lower (1.01), whereas that for D12S1042 increased to 1.73. Among families positive for the APOE-epsilon 4 allele, none of the LOD scores reached 1. Multipoint affected-relative-pair analysis showed peaks at D12S1623 (nonparametric linkage [NPL] score 1.52; P=.028) and near D12S1042, at D12S1057 (NPL score 1.57; P=.027). NPL scores for both D12S1623 and D12S1057 increased in families affected with LOAD, but, in APOE-epsilon 4-negative families, only scores for the region flanking D12S1623 remained elevated (NPL score 1.74; P=.013). This study of Caribbean Hispanics with familial AD extends and provides modest evidence of linkage to loci on chromosome 12p. Linkage varied by age at onset of AD and by the presence or absence of the APOE-epsilon 4 allele.

[Impact of facial emotional recognition alterations in Dementia of the Alzheimer type].

PubMed

Rubinstein, Wanda; Cossini, Florencia; Politis, Daniel

2016-07-01

Face recognition of basic emotions is independent of other deficits in dementia of the Alzheimer type. Among these deficits, there is disagreement about what emotions are more difficult to recognize. Our aim was to study the presence of alterations in the process of facial recognition of basic emotions, and to investigate if there were differences in the recognition of each type of emotion in Alzheimer's disease. With three tests of recognition of basic facial emotions we evaluated 29 patients who had been diagnosed with dementia of the Alzheimer type and 18 control subjects. Significant differences were obtained in tests of recognition of basic facial emotions and between each. Since the amygdala, one of the brain structures responsible for emotional reaction, is affected in the early stages of this disease, our findings become relevant to understand how this alteration of the process of emotional recognition impacts the difficulties these patients have in both interpersonal relations and behavioral disorders.

Selective Attention in Early Dementia of Alzheimer Type

ERIC Educational Resources Information Center

Fernandez-Duque, Diego; Black, Sandra E.

2008-01-01

This study explored possible deficits in selective attention brought about by Dementia of Alzheimer Type (DAT). In three experiments, we tested patients with early DAT, healthy elderly, and young adults under low memory demands to assess perceptual filtering, conflict resolution, and set switching abilities. We found no evidence of impaired…

SORL1 is genetically associated with late-onset Alzheimer's disease in Japanese, Koreans and Caucasians.

PubMed

Miyashita, Akinori; Koike, Asako; Jun, Gyungah; Wang, Li-San; Takahashi, Satoshi; Matsubara, Etsuro; Kawarabayashi, Takeshi; Shoji, Mikio; Tomita, Naoki; Arai, Hiroyuki; Asada, Takashi; Harigaya, Yasuo; Ikeda, Masaki; Amari, Masakuni; Hanyu, Haruo; Higuchi, Susumu; Ikeuchi, Takeshi; Nishizawa, Masatoyo; Suga, Masaichi; Kawase, Yasuhiro; Akatsu, Hiroyasu; Kosaka, Kenji; Yamamoto, Takayuki; Imagawa, Masaki; Hamaguchi, Tsuyoshi; Yamada, Masahito; Morihara, Takashi; Moriaha, Takashi; Takeda, Masatoshi; Takao, Takeo; Nakata, Kenji; Fujisawa, Yoshikatsu; Sasaki, Ken; Watanabe, Ken; Nakashima, Kenji; Urakami, Katsuya; Ooya, Terumi; Takahashi, Mitsuo; Yuzuriha, Takefumi; Serikawa, Kayoko; Yoshimoto, Seishi; Nakagawa, Ryuji; Kim, Jong-Won; Ki, Chang-Seok; Won, Hong-Hee; Na, Duk L; Seo, Sang Won; Mook-Jung, Inhee; St George-Hyslop, Peter; Mayeux, Richard; Haines, Jonathan L; Pericak-Vance, Margaret A; Yoshida, Makiko; Nishida, Nao; Tokunaga, Katsushi; Yamamoto, Ken; Tsuji, Shoji; Kanazawa, Ichiro; Ihara, Yasuo; Schellenberg, Gerard D; Farrer, Lindsay A; Kuwano, Ryozo

2013-01-01

To discover susceptibility genes of late-onset Alzheimer's disease (LOAD), we conducted a 3-stage genome-wide association study (GWAS) using three populations: Japanese from the Japanese Genetic Consortium for Alzheimer Disease (JGSCAD), Koreans, and Caucasians from the Alzheimer Disease Genetic Consortium (ADGC). In Stage 1, we evaluated data for 5,877,918 genotyped and imputed SNPs in Japanese cases (n = 1,008) and controls (n = 1,016). Genome-wide significance was observed with 12 SNPs in the APOE region. Seven SNPs from other distinct regions with p-values <2×10(-5) were genotyped in a second Japanese sample (885 cases, 985 controls), and evidence of association was confirmed for one SORL1 SNP (rs3781834, P = 7.33×10(-7) in the combined sample). Subsequent analysis combining results for several SORL1 SNPs in the Japanese, Korean (339 cases, 1,129 controls) and Caucasians (11,840 AD cases, 10,931 controls) revealed genome wide significance with rs11218343 (P = 1.77×10(-9)) and rs3781834 (P = 1.04×10(-8)). SNPs in previously established AD loci in Caucasians showed strong evidence of association in Japanese including rs3851179 near PICALM (P = 1.71×10(-5)) and rs744373 near BIN1 (P = 1.39×10(-4)). The associated allele for each of these SNPs was the same as in Caucasians. These data demonstrate for the first time genome-wide significance of LOAD with SORL1 and confirm the role of other known loci for LOAD in Japanese. Our study highlights the importance of examining associations in multiple ethnic populations.

Linkage analyses in Caribbean Hispanic families identify novel loci associated with familial late-onset Alzheimer's disease.

PubMed

Barral, Sandra; Cheng, Rong; Reitz, Christiane; Vardarajan, Badri; Lee, Joseph; Kunkle, Brian; Beecham, Gary; Cantwell, Laura S; Pericak-Vance, Margaret A; Farrer, Lindsay A; Haines, Jonathan L; Goate, Alison M; Foroud, Tatiana; Boerwinkle, Eric; Schellenberg, Gerard D; Mayeux, Richard

2015-12-01

We performed linkage analyses in Caribbean Hispanic families with multiple late-onset Alzheimer's disease (LOAD) cases to identify regions that may contain disease causative variants. We selected 67 LOAD families to perform genome-wide linkage scan. Analysis of the linked regions was repeated using the entire sample of 282 families. Validated chromosomal regions were analyzed using joint linkage and association. We identified 26 regions linked to LOAD (HLOD ≥3.6). We validated 13 of the regions (HLOD ≥2.5) using the entire family sample. The strongest signal was at 11q12.3 (rs2232932: HLODmax = 4.7, Pjoint = 6.6 × 10(-6)), a locus located ∼2 Mb upstream of the membrane-spanning 4A gene cluster. We additionally identified a locus at 7p14.3 (rs10255835: HLODmax = 4.9, Pjoint = 1.2 × 10(-5)), a region harboring genes associated with the nervous system (GARS, GHRHR, and NEUROD6). Future sequencing efforts should focus on these regions because they may harbor familial LOAD causative mutations. Copyright © 2015 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Diagnostic Utility of the Shortened Version of the Wisconsin Card Sorting Test in Patients With Sporadic Late Onset Alzheimer Disease.

PubMed

Sánchez, Juan Luis; Martín, Javier; López, Carolina

2017-12-01

The classic version of the Wisconsin Card Sorting Test (WCST) consists of correctly sorting 128 cards according to changing sorting criteria. Its application is costly in terms of the time employed, with all the negative consequences this entails (decrease in motivation, frustration, and fatigue). The main objective of this study was to test the usefulness of the shortened version of the WCST as compared to the full test by analyzing the equivalence between the two decks comprising the full 128-card version on a sample of patients diagnosed with sporadic late onset Alzheimer disease (SLOAD) and to check its clinical usefulness. The variables showed equivalence between the two decks and their ability to differentiate between the control group (CG) and the Alzheimer disease (AD) group. The scores obtained suggest equivalence between decks and that the application of only the first deck is sufficient.

Eyetracking Metrics in Young Onset Alzheimer's Disease: A Window into Cognitive Visual Functions.

PubMed

Pavisic, Ivanna M; Firth, Nicholas C; Parsons, Samuel; Rego, David Martinez; Shakespeare, Timothy J; Yong, Keir X X; Slattery, Catherine F; Paterson, Ross W; Foulkes, Alexander J M; Macpherson, Kirsty; Carton, Amelia M; Alexander, Daniel C; Shawe-Taylor, John; Fox, Nick C; Schott, Jonathan M; Crutch, Sebastian J; Primativo, Silvia

2017-01-01

Young onset Alzheimer's disease (YOAD) is defined as symptom onset before the age of 65 years and is particularly associated with phenotypic heterogeneity. Atypical presentations, such as the clinic-radiological visual syndrome posterior cortical atrophy (PCA), often lead to delays in accurate diagnosis. Eyetracking has been used to demonstrate basic oculomotor impairments in individuals with dementia. In the present study, we aim to explore the relationship between eyetracking metrics and standard tests of visual cognition in individuals with YOAD. Fifty-seven participants were included: 36 individuals with YOAD ( n  = 26 typical AD; n  = 10 PCA) and 21 age-matched healthy controls. Participants completed three eyetracking experiments: fixation, pro-saccade, and smooth pursuit tasks. Summary metrics were used as outcome measures and their predictive value explored looking at correlations with visuoperceptual and visuospatial metrics. Significant correlations between eyetracking metrics and standard visual cognitive estimates are reported. A machine-learning approach using a classification method based on the smooth pursuit raw eyetracking data discriminates with approximately 95% accuracy patients and controls in cross-validation tests. Results suggest that the eyetracking paradigms of a relatively simple and specific nature provide measures not only reflecting basic oculomotor characteristics but also predicting higher order visuospatial and visuoperceptual impairments. Eyetracking measures can represent extremely useful markers during the diagnostic phase and may be exploited as potential outcome measures for clinical trials.

Association Studies of 22 Candidate SNPs with Late-Onset Alzheimer's Disease

PubMed Central

Figgins, Jessica A.; Minster, Ryan L.; Demirci, F. Yesim; DeKosky, Steven T.; Kamboh, M. Ilyas

2009-01-01

Alzheimer's disease (AD) is a complex and multifactorial disease with the possible involvement of several genes. With the exception of the APOE gene as a susceptibility marker, no other genes have been shown consistently to be associated with late-onset AD (LOAD). A recent genome-wide association study of 17,343 gene-based putative functional single nucleotide polymorphisms (SNPs) found 19 significant variants, including 3 linked to APOE, showing association with LOAD (Hum Mol Genet 2007; 16:865–873). We have set out to replicate the 16 new significant associations in a large case-control cohort of American Whites. Additionally, we examined six variants present in positional and/or biological candidate genes for AD. We genotyped the 22 SNPs in up to 1,009 Caucasian Americans with LOAD and up to 1,010 age-matched healthy Caucasian Americans, using 5′ nuclease assays. We did not observe a statistically significant association between the SNPs and the risk of AD, either individually or stratified by APOE. Our data suggest that the association of the studied variants with LOAD risk, if it exists, is not statistically significant in our sample. PMID:18780302

Comparison of clinical characteristics between familial and non-familial early onset Alzheimer's disease.

PubMed

Joshi, Aditi; Ringman, John M; Lee, Albert S; Juarez, Kevin O; Mendez, Mario F

2012-10-01

Although familial Alzheimer's disease (FAD) is an early onset AD (EAD), most patients with EAD do not have a familial disorder. Recent guidelines recommend testing for genes causing FAD only in those EAD patients with two first-degree relatives. However, some patients with FAD may lack a known family history or other indications for suspecting FAD but might nonetheless be carriers of FAD mutations. The study was aimed to identify clinical features that distinguish FAD from non-familial EAD (NF-EAD). A retrospective review of a university-based cohort of 32 FAD patients with PSEN1-related AD and 81 with NF-EAD was conducted. The PSEN1 patients, compared to the NF-EAD patients, had an earlier age of disease onset (41.8 ± 5.2 vs. 55.9 ± 4.8 years) and, at initial assessment, a longer disease duration (5.1 ± 3.4 vs. 3.3 ± 2.6 years) and lower MMSE scores (10.74 ± 8.0 vs. 20.95 ± 5.8). Patients with NF-EAD were more likely to present with non-memory deficits, particularly visuospatial symptoms, than were FAD patients. When age, disease duration, and MMSE scores were controlled in a logistical regression model, FAD patients were more likely to have significant headaches, myoclonus, gait abnormality, and pseudobulbar affect than those with NF-EAD. In addition to a much younger age of onset, FAD patients with PSEN1 mutations differed from those with NF-EAD by a history of headaches and pseudobulbar affect, as well as myoclonus and gait abnormality on examination. These may represent differences in pathophysiology between FAD and NF-EAD and in some contexts such findings should lead to genetic counseling and appropriate recommendations for genetic testing for FAD.

Early-versus Late-Onset Alzheimer Disease: Long-Term Functional Outcomes, Nursing Home Placement, and Risk Factors for Rate of Progression.

PubMed

Wattmo, Carina; Wallin, Åsa K

2017-01-01

Whether age at onset influences functional deterioration in Alzheimer disease (AD) is unclear. We, therefore, investigated risk factors for progression in activities of daily living (ADL) and nursing home placement (NHP) in cholinesterase inhibitor (ChEI)-treated patients with early-onset AD (EOAD) versus late-onset AD (LOAD). This 3-year, prospective, observational, multicenter study included 1,017 participants with mild-to-moderate AD; 143 had EOAD (onset <65 years) and 874 LOAD (onset ≥65 years). Possible sociodemographic and clinical factors that could affect functional outcome and NHP were analyzed using mixed-effects models and logistic regression, respectively. Younger individuals exhibited longer illness duration before AD diagnosis, whereas 6-month functional response to ChEI therapy, 3-year changes in ADL capacities, time from diagnosis to NHP, and survival time in nursing homes were similar between the groups. In LOAD, a higher ChEI dose, no antidepressant use, and lower education level were protective factors for slower instrumental ADL (IADL) decline. In EOAD, antihypertensives/cardiac therapy implied faster IADL progression but lower risk of NHP. This study highlights the clinical importance of an earlier diagnosis and treatment initiation and the need for functional evaluations in EOAD. Despite the age differences between EOAD and LOAD, a similar need for nursing homes was observed.

7T T₂*-weighted magnetic resonance imaging reveals cortical phase differences between early- and late-onset Alzheimer's disease.

PubMed

van Rooden, Sanneke; Doan, Nhat Trung; Versluis, Maarten J; Goos, Jeroen D C; Webb, Andrew G; Oleksik, Ania M; van der Flier, Wiesje M; Scheltens, Philip; Barkhof, Frederik; Weverling-Rynsburger, Annelies W E; Blauw, Gerard Jan; Reiber, Johan H C; van Buchem, Mark A; Milles, Julien; van der Grond, Jeroen

2015-01-01

The aim of this study is to explore regional iron-related differences in the cerebral cortex, indicative of Alzheimer's disease pathology, between early- and late-onset Alzheimer's disease (EOAD, LOAD, respectively) patients using 7T magnetic resonance phase images. High-resolution T2(∗)-weighted scans were acquired in 12 EOAD patients and 17 LOAD patients with mild to moderate disease and 27 healthy elderly control subjects. Lobar peak-to-peak phase shifts and regional mean phase contrasts were computed. An increased peak-to-peak phase shift was found for all lobar regions in EOAD patients compared with LOAD patients (p < 0.05). Regional mean phase contrast in EOAD patients was higher than in LOAD patients in the superior medial and middle frontal gyrus, anterior and middle cingulate gyrus, postcentral gyrus, superior and inferior parietal gyrus, and precuneus (p ≤ 0.042). These data suggest that EOAD patients have an increased iron accumulation, possibly related to an increased amyloid deposition, in specific cortical regions as compared with LOAD patients. Copyright © 2015 Elsevier Inc. All rights reserved.

No association between SNP rs498055 on chromosome 10 and late-onset Alzheimer disease in multiple datasets.

PubMed

Liang, Xueying; Schnetz-Boutaud, Nathalie; Bartlett, Jackie; Allen, Melissa J; Gwirtsman, Harry; Schmechel, Don E; Carney, Regina M; Gilbert, John R; Pericak-Vance, Margaret A; Haines, Jonathan L

2008-01-01

SNP rs498055 in the predicted gene LOC439999 on chromosome 10 was recently identified as being strongly associated with late-onset Alzheimer disease (LOAD). This SNP falls within a chromosomal region that has engendered continued interest generated from both preliminary genetic linkage and candidate gene studies. To independently evaluate this interesting candidate SNP we examined four independent datasets, three family-based and one case-control. All the cases were late-onset AD Caucasian patients with minimum age at onset >or= 60 years. None of the three family samples or the combined family-based dataset showed association in either allelic or genotypic family-based association tests at p < 0.05. Both original and OSA two-point LOD scores were calculated. However, there was no evidence indicating linkage no matter what covariates were applied (the highest LOD score was 0.82). The case-control dataset did not demonstrate any association between this SNP and AD (all p-values > 0.52). Our results do not confirm the previous association, but are consistent with a more recent negative association result that used family-based association tests to examine the effect of this SNP in two family datasets. Thus we conclude that rs498055 is not associated with an increased risk of LOAD.

Retinoid receptors, transporters, and metabolizers as therapeutic targets in late onset Alzheimer disease.

PubMed

Goodman, Ann B

2006-12-01

Vitamin A (retinoid) is required in the adult brain to enable cognition, learning, and memory. While brain levels of retinoid diminish over the course of normal ageing, retinoid deficit is greater in late onset Alzheimer disease (LOAD) brains than in normal-aged controls. This paper reviews recent evidence supporting these statements and further suggests that genes necessary for the synthesis, transport and function of retinoid to and within the ageing brain are appropriate targets for treatment of LOAD. These genes tend to be clustered with genes that have been proposed as candidates in LOAD, are found at chromosomal regions linked to LOAD, and suggest the possibility of an overall coordinated regulation. This phenomenon is termed Chromeron and is analogous to the operon mechanism observed in prokaryotes. Suggested treatment targets are the retinoic-acid inactivating enzymes (CYP26)s, the retinol binding and transport proteins, retinol-binding protein (RBP)4 and transthyretin (TTR), and the retinoid receptors. TTR as a LOAD target is the subject of active investigation. The retinoid receptors and the retinoid-inactivating enzymes have previously been proposed as targets. This is the first report to suggest that RBP4 is an amenable treatment target in LOAD. RBP4 is elevated in type-2 diabetes and obesity, conditions associated with increased risk for LOAD. Fenretinide, a novel synthetic retinoic acid (RA) analog lowers RBP4 in glucose intolerant obese mice. The feasibility of using fenretinide either as an adjunct to present LOAD therapies, or on its own as an early prevention strategy should be determined. (c) 2006 Wiley-Liss, Inc.

Polygenic risk scores in familial Alzheimer disease

PubMed Central

Tosto, Giuseppe; Bird, Thomas D.; Tsuang, Debby; Bennett, David A.; Boeve, Bradley F.; Cruchaga, Carlos; Faber, Kelley; Foroud, Tatiana M.; Farlow, Martin; Goate, Alison M.; Bertlesen, Sarah; Graff-Radford, Neill R.; Medrano, Martin; Lantigua, Rafael; Manly, Jennifer; Ottman, Ruth; Rosenberg, Roger; Schaid, Daniel J.; Schupf, Nicole; Stern, Yaakov; Sweet, Robert A.

2017-01-01

Objective: To investigate the association between a genetic risk score (GRS) and familial late-onset Alzheimer disease (LOAD) and its predictive value in families multiply affected by the disease. Methods: Using data from the National Institute on Aging Genetics Initiative for Late-Onset Alzheimer Disease (National Institute on Aging–Late-Onset Alzheimer's Disease Family Study), mixed regression models tested the association of familial LOAD with a GRS based on single nucleotide polymorphisms (SNPs) previously associated with LOAD. We modeled associations using unweighted and weighted scores with estimates derived from the literature. In secondary models, we adjusted subsequent models for presence of the APOE ε4 allele and further tested the interaction between APOE ε4 and the GRS. We constructed a similar GRS in a cohort of Caribbean Hispanic families multiply affected by LOAD by selecting the SNP with the strongest p value within the same regions. Results: In the NIA-LOAD families, the GRS was significantly associated with LOAD (odds ratio [OR] 1.29; 95% confidence interval 1.21–1.37). The results did not change after adjusting for APOE ε4. In Caribbean Hispanic families, the GRS also significantly predicted LOAD (OR 1.73; 1.57–1.93). Higher scores were associated with lower age at onset in both cohorts. Conclusions: High GRS increases the risk of familial LOAD and lowers the age at onset, regardless of ethnic group. PMID:28213371

Polygenic risk scores in familial Alzheimer disease.

PubMed

Tosto, Giuseppe; Bird, Thomas D; Tsuang, Debby; Bennett, David A; Boeve, Bradley F; Cruchaga, Carlos; Faber, Kelley; Foroud, Tatiana M; Farlow, Martin; Goate, Alison M; Bertlesen, Sarah; Graff-Radford, Neill R; Medrano, Martin; Lantigua, Rafael; Manly, Jennifer; Ottman, Ruth; Rosenberg, Roger; Schaid, Daniel J; Schupf, Nicole; Stern, Yaakov; Sweet, Robert A; Mayeux, Richard

2017-03-21

To investigate the association between a genetic risk score (GRS) and familial late-onset Alzheimer disease (LOAD) and its predictive value in families multiply affected by the disease. Using data from the National Institute on Aging Genetics Initiative for Late-Onset Alzheimer Disease (National Institute on Aging-Late-Onset Alzheimer's Disease Family Study), mixed regression models tested the association of familial LOAD with a GRS based on single nucleotide polymorphisms (SNPs) previously associated with LOAD. We modeled associations using unweighted and weighted scores with estimates derived from the literature. In secondary models, we adjusted subsequent models for presence of the APOE ε4 allele and further tested the interaction between APOE ε4 and the GRS. We constructed a similar GRS in a cohort of Caribbean Hispanic families multiply affected by LOAD by selecting the SNP with the strongest p value within the same regions. In the NIA-LOAD families, the GRS was significantly associated with LOAD (odds ratio [OR] 1.29; 95% confidence interval 1.21-1.37). The results did not change after adjusting for APOE ε4. In Caribbean Hispanic families, the GRS also significantly predicted LOAD (OR 1.73; 1.57-1.93). Higher scores were associated with lower age at onset in both cohorts. High GRS increases the risk of familial LOAD and lowers the age at onset, regardless of ethnic group. © 2017 American Academy of Neurology.

Posterior cortical atrophy variant of Alzheimer's dementia-A case report.

PubMed

Mukku, Shiva Shanker Reddy; Chintala, Haripriya; Nagaraj, Chandana; Mangalore, Sandhya; Sivakumar, Palanimuthu T; Varghese, Mathew

2018-05-17

Alzheimer's dementia (AD) is the commonest type of dementia presenting with initial episodic memory decline followed by involvement of other cognitive domains. Posterior cortical atrophy (PCA) is one of the variants of Alzheimer's dementia (AD) characterized by the atypical presentation of relatively persevered memory in the initial stage. PCA is an uncommon early onset dementia affecting adults between 50 and 65 years. It presents predominantly with visuo-spatial and visuo-perceptual deficits. PCA is a phenotype with varied etiology most common being Alzheimer's disease. The complex and atypical presentation with preserved memory and insight in patients with PCA poses challenge to clinicians in diagnosing at initial stages. There is also paucity of research on prevalence, course, prognosis and management of PCA. In this article we describe a middle aged gentlemen presenting with clinical features suggestive of PCA. We also discussed relevant literature. Copyright © 2018 Elsevier B.V. All rights reserved.

Segregation analysis of Alzheimer pedigrees: Rare Mendelian dominant mutation(s) explain a minority of early-onset cases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martinez, M.; Campion, D.; Babron, M.C.

1996-02-16

Segregation analysis of Alzheimer disease (AD) in 92 families ascertained through early-onset ({le}age 60 years) AD (EOAD) probands has been carried out, allowing for a mixture in AD inheritance among probands. The goal was to quantify the proportion of probands that could be explained by autosomal inheritance of a rare disease allele {open_quotes}a{close_quotes} at a Mendelian dominant gene (MDG). Our data provide strong evidence for a mixture of two distributions; AD transmission is fully explained by MDG inheritance in <20% of probands. Male and female age-of-onset distributions are significantly different for {open_quotes}AA{close_quote} but not for {open_quotes}aA{close_quote} subjects. For {open_quotes}aA{close_quote} subjectsmore » the estimated penetrance value was close to 1 by age 60. For {open_quotes}AA{close_quotes} subjects, it reaches, by age 90, 10% (males) and 30% (females). We show a clear cutoff in the posterior probability of being an MDG case. 10 refs., 1 tab.« less

Linkage of familial Alzheimer disease to chromosome 14 in two large early-onset pedigrees: effects of marker allele frequencies on lod scores.

PubMed

Nechiporuk, A; Fain, P; Kort, E; Nee, L E; Frommelt, E; Polinsky, R J; Korenberg, J R; Pulst, S M

1993-05-01

Alzheimer disease (AD) is a devastating neurodegenerative disease leading to global dementia. In addition to sporadic forms of AD, familial forms (FAD) have been recognized. Mutations in the amyloid precursor protein (APP) gene on chromosome (CHR) 21 have been shown to cause early-onset AD in a small number of pedigrees. Recently, linkage to markers on CHR 14 has been established in several early-onset FAD pedigrees. We now report lod scores for CHR 14 markers in two large early-onset FAD pedigrees. Pairwise linkage analysis suggested that in these pedigrees the mutation is tightly linked to the loci D14S43 and D14S53. However, assumptions regarding marker allele frequencies had a major and often unpredictable effect on calculated lod scores. Therefore, caution needs to be exercised when single pedigrees are analyzed with marker allele frequencies determined from the literature or from a pool of spouses.

Glutaric aciduria type 2, late onset type in Thai siblings with myopathy.

PubMed

Wasant, Pornswan; Kuptanon, Chulaluck; Vattanavicharn, Nithiwat; Liammongkolkul, Somporn; Ratanarak, Pisanu; Sangruchi, Tumtip; Yamaguchi, Seiji

2010-10-01

Reported here is a novel presentation of late onset glutaric aciduria type 2 in two Thai siblings. A 9-year-old boy presented with gradual onset of proximal muscle weakness for 6 weeks. The initial diagnosis was postviral myositis, and then polymyositis. Electromyography and nerve conduction velocity testing indicated a myopathic pattern. Muscle biopsy revealed excessive accumulation of fat. Acylcarnitine profiling led to the diagnosis of glutaric aciduria type 2. Immunoblot analysis of electron-transferring-flavoprotein and its dehydrogenase electron-transferring-flavoprotein dehydrogenase led to mutation analysis of the ETFDH gene, which revealed two different pathogenic mutations in both alleles and confirmed the diagnosis of glutaric aciduria type 2 caused by electron-transferring-flavoprotein dehydrogenase deficiency. The boy recovered completely after treatment. Later, his younger sibling became symptomatic; the same diagnosis was confirmed, and treatment was similarly effective. Acylcarnitine profiling was a crucial investigation in making this diagnosis in the presence of normal urine organic acid findings. Late onset glutaric aciduria type 2, a rare cause of muscle weakness in children, should be included in the differential diagnosis of myopathy. Copyright © 2010 Elsevier Inc. All rights reserved.

The Cache County Study on Memory in Aging: Factors Affecting Risk of Alzheimer's disease and its Progression after Onset

PubMed Central

Tschanz, JoAnn T.; Norton, Maria C.; Zandi, Peter P.; Lyketsos, Constantine G.

2014-01-01

The Cache County Study on Memory in Aging is a longitudinal, population-based study of Alzheimer's disease (AD) and other dementias. Initiated in 1995 and extending to 2013, the study has followed over 5,000 elderly residents of Cache County, Utah (USA) for over twelve years. Achieving a 90% participation rate at enrollment, and spawning two ancillary projects, the study has contributed to the literature on genetic, psychosocial and environmental risk factors for AD, late life cognitive decline, and the clinical progression of dementia after its onset. This paper describes the major study contributions to the literature on AD and dementia. PMID:24423221

The Cache County Study on Memory in Aging: factors affecting risk of Alzheimer's disease and its progression after onset.

PubMed

Tschanz, Joann T; Norton, Maria C; Zandi, Peter P; Lyketsos, Constantine G

2013-12-01

The Cache County Study on Memory in Aging is a longitudinal, population-based study of Alzheimer's disease (AD) and other dementias. Initiated in 1995 and extending to 2013, the study has followed over 5,000 elderly residents of Cache County, Utah (USA) for over twelve years. Achieving a 90% participation rate at enrolment, and spawning two ancillary projects, the study has contributed to the literature on genetic, psychosocial and environmental risk factors for AD, late-life cognitive decline, and the clinical progression of dementia after its onset. This paper describes the major study contributions to the literature on AD and dementia.

Impact of DNA testing for early-onset familial Alzheimer disease and frontotemporal dementia.

PubMed

Steinbart, E J; Smith, C O; Poorkaj, P; Bird, T D

2001-11-01

DNA testing of persons at risk for hereditary, degenerative neurologic diseases is relatively new. Only anecdotal reports of such testing in familial Alzheimer disease (FAD) exist, and little is know about the personal and social impact of such testing. In a descriptive, observational study, individuals at 50% risk for autosomal dominant, early-onset FAD or frontotemporal dementia with parkinsonism linked to chromosome 17 underwent DNA testing for the genetic mutations previously identified in affected family members. Individuals were followed up for (1/2) to 3 years and were interviewed regarding attitudes toward the testing process and the impact of the results. Twenty-one (8.4%) of 251 persons at risk for FAD or frontotemporal dementia requested genetic testing. The most common reasons for requesting testing were concern about early symptoms of dementia, financial or family planning, and relief from anxiety. Twelve individuals had positive DNA test results, and 6 of these had early symptoms of dementia; 8 had negative results; and 1 has not yet received results. Of 14 asymptomatic individuals completing testing, 13 believed the testing was beneficial. Two persons reported moderate anxiety and 1 reported moderate depression. As expected, persons with negative test results had happier experiences overall, but even they had to deal with ongoing anxiety and depression. Thus far, there have been no psychiatric hospitalizations, suicide attempts, or denials of insurance. Genetic testing in early-onset FAD and frontotemporal dementia can be completed successfully. Most individuals demonstrate effective coping skills and find the testing to be beneficial, but long-term effects remain unknown.

Late-onset Alzheimer disease genetic variants in posterior cortical atrophy and posterior AD.

PubMed

Carrasquillo, Minerva M; Khan, Qurat ul Ain; Murray, Melissa E; Krishnan, Siddharth; Aakre, Jeremiah; Pankratz, V Shane; Nguyen, Thuy; Ma, Li; Bisceglio, Gina; Petersen, Ronald C; Younkin, Steven G; Dickson, Dennis W; Boeve, Bradley F; Graff-Radford, Neill R; Ertekin-Taner, Nilüfer

2014-04-22

To investigate association of genetic risk factors for late-onset Alzheimer disease (LOAD) with risk of posterior cortical atrophy (PCA), a syndrome of visual impairment with predominant Alzheimer disease (AD) pathology in posterior cortical regions, and with risk of "posterior AD" neuropathology. We assessed 81 participants with PCA diagnosed clinically and 54 with neuropathologic diagnosis of posterior AD vs 2,523 controls for association with 11 significant single nucleotide polymorphisms (SNPs) from published LOAD risk genome-wide association studies. There was highly significant association with APOE ε4 and increased risk of PCA (p = 0.0003, odds ratio [OR] = 3.17) and posterior AD (p = 1.11 × 10(-17), OR = 6.43). No other locus was significant after corrections for multiple testing, although rs11136000 near CLU (p = 0.019, OR = 0.60) and rs744373 near BIN1 (p = 0.025, OR = 1. 63) associated nominally significantly with posterior AD, and rs3851179 at the PICALM locus had significant association with PCA (p = 0.0003, OR = 2.84). ABCA7 locus SNP rs3764650, which was also tested under the recessive model because of Hardy-Weinberg disequilibrium, also had nominally significant association with PCA risk. The direction of association at APOE, CLU, and BIN1 loci was the same for participants with PCA and posterior AD. The effects for all SNPs, except rs3851179, were consistent with those for LOAD risk. We identified a significant effect for APOE and nominate CLU, BIN1, and ABCA7 as additional risk loci for PCA and posterior AD. Our findings suggest that at least some of the genetic risk factors for LOAD are shared with these atypical conditions and provide effect-size estimates for their future genetic studies.

Data-driven models of dominantly-inherited Alzheimer's disease progression.

PubMed

Oxtoby, Neil P; Young, Alexandra L; Cash, David M; Benzinger, Tammie L S; Fagan, Anne M; Morris, John C; Bateman, Randall J; Fox, Nick C; Schott, Jonathan M; Alexander, Daniel C

2018-05-01

See Li and Donohue (doi:10.1093/brain/awy089) for a scientific commentary on this article.Dominantly-inherited Alzheimer's disease is widely hoped to hold the key to developing interventions for sporadic late onset Alzheimer's disease. We use emerging techniques in generative data-driven disease progression modelling to characterize dominantly-inherited Alzheimer's disease progression with unprecedented resolution, and without relying upon familial estimates of years until symptom onset. We retrospectively analysed biomarker data from the sixth data freeze of the Dominantly Inherited Alzheimer Network observational study, including measures of amyloid proteins and neurofibrillary tangles in the brain, regional brain volumes and cortical thicknesses, brain glucose hypometabolism, and cognitive performance from the Mini-Mental State Examination (all adjusted for age, years of education, sex, and head size, as appropriate). Data included 338 participants with known mutation status (211 mutation carriers in three subtypes: 163 PSEN1, 17 PSEN2, and 31 APP) and a baseline visit (age 19-66; up to four visits each, 1.1 ± 1.9 years in duration; spanning 30 years before, to 21 years after, parental age of symptom onset). We used an event-based model to estimate sequences of biomarker changes from baseline data across disease subtypes (mutation groups), and a differential equation model to estimate biomarker trajectories from longitudinal data (up to 66 mutation carriers, all subtypes combined). The two models concur that biomarker abnormality proceeds as follows: amyloid deposition in cortical then subcortical regions (∼24 ± 11 years before onset); phosphorylated tau (17 ± 8 years), tau and amyloid-β changes in cerebrospinal fluid; neurodegeneration first in the putamen and nucleus accumbens (up to 6 ± 2 years); then cognitive decline (7 ± 6 years), cerebral hypometabolism (4 ± 4 years), and further regional neurodegeneration. Our models predicted symptom onset more

Deleterious ABCA7 mutations and transcript rescue mechanisms in early onset Alzheimer's disease.

PubMed

De Roeck, Arne; Van den Bossche, Tobi; van der Zee, Julie; Verheijen, Jan; De Coster, Wouter; Van Dongen, Jasper; Dillen, Lubina; Baradaran-Heravi, Yalda; Heeman, Bavo; Sanchez-Valle, Raquel; Lladó, Albert; Nacmias, Benedetta; Sorbi, Sandro; Gelpi, Ellen; Grau-Rivera, Oriol; Gómez-Tortosa, Estrella; Pastor, Pau; Ortega-Cubero, Sara; Pastor, Maria A; Graff, Caroline; Thonberg, Håkan; Benussi, Luisa; Ghidoni, Roberta; Binetti, Giuliano; de Mendonça, Alexandre; Martins, Madalena; Borroni, Barbara; Padovani, Alessandro; Almeida, Maria Rosário; Santana, Isabel; Diehl-Schmid, Janine; Alexopoulos, Panagiotis; Clarimon, Jordi; Lleó, Alberto; Fortea, Juan; Tsolaki, Magda; Koutroumani, Maria; Matěj, Radoslav; Rohan, Zdenek; De Deyn, Peter; Engelborghs, Sebastiaan; Cras, Patrick; Van Broeckhoven, Christine; Sleegers, Kristel

2017-09-01

Premature termination codon (PTC) mutations in the ATP-Binding Cassette, Sub-Family A, Member 7 gene (ABCA7) have recently been identified as intermediate-to-high penetrant risk factor for late-onset Alzheimer's disease (LOAD). High variability, however, is observed in downstream ABCA7 mRNA and protein expression, disease penetrance, and onset age, indicative of unknown modifying factors. Here, we investigated the prevalence and disease penetrance of ABCA7 PTC mutations in a large early onset AD (EOAD)-control cohort, and examined the effect on transcript level with comprehensive third-generation long-read sequencing. We characterized the ABCA7 coding sequence with next-generation sequencing in 928 EOAD patients and 980 matched control individuals. With MetaSKAT rare variant association analysis, we observed a fivefold enrichment (p = 0.0004) of PTC mutations in EOAD patients (3%) versus controls (0.6%). Ten novel PTC mutations were only observed in patients, and PTC mutation carriers in general had an increased familial AD load. In addition, we observed nominal risk reducing trends for three common coding variants. Seven PTC mutations were further analyzed using targeted long-read cDNA sequencing on an Oxford Nanopore MinION platform. PTC-containing transcripts for each investigated PTC mutation were observed at varying proportion (5-41% of the total read count), implying incomplete nonsense-mediated mRNA decay (NMD). Furthermore, we distinguished and phased several previously unknown alternative splicing events (up to 30% of transcripts). In conjunction with PTC mutations, several of these novel ABCA7 isoforms have the potential to rescue deleterious PTC effects. In conclusion, ABCA7 PTC mutations play a substantial role in EOAD, warranting genetic screening of ABCA7 in genetically unexplained patients. Long-read cDNA sequencing revealed both varying degrees of NMD and transcript-modifying events, which may influence ABCA7 dosage, disease severity, and may

A founder mutation in presenilin 1 causing early-onset Alzheimer disease in unrelated Caribbean Hispanic families.

PubMed

Athan, E S; Williamson, J; Ciappa, A; Santana, V; Romas, S N; Lee, J H; Rondon, H; Lantigua, R A; Medrano, M; Torres, M; Arawaka, S; Rogaeva, E; Song, Y Q; Sato, C; Kawarai, T; Fafel, K C; Boss, M A; Seltzer, W K; Stern, Y; St George-Hyslop, P; Tycko, B; Mayeux, R

2001-11-14

Genetic determinants of Alzheimer disease (AD) have not been comprehensively examined in Caribbean Hispanics, a population in the United States in whom the frequency of AD is higher compared with non-Hispanic whites. To identify variant alleles in genes related to familial early-onset AD among Caribbean Hispanics. Family-based case series conducted in 1998-2001 at an AD research center in New York, NY, and clinics in the Dominican Republic. Among 206 Caribbean Hispanic families with 2 or more living members with AD who were identified, 19 (9.2%) had at least 1 individual with onset of AD before the age of 55 years. The entire coding region of the presenilin 1 gene and exons 16 and 17 of the amyloid precursor protein gene were sequenced in probands from the 19 families and their living relatives. A G-to-C nucleotide change resulting in a glycine-alanine amino acid substitution at codon 206 (Gly206Ala) in exon 7 of presenilin 1 was observed in 23 individuals from 8 (42%) of the 19 families. A Caribbean Hispanic individual with the Gly206Ala mutation and early-onset familial disease was also found by sequencing the corresponding genes of 319 unrelated individuals in New York City. The Gly206Ala mutation was not found in public genetic databases but was reported in 5 individuals from 4 Hispanic families with AD referred for genetic testing. None of the members of these families were related to one another, yet all carriers of the Gly206Ala mutation tested shared a variant allele at 2 nearby microsatellite polymorphisms, indicating a common ancestor. No mutations were found in the amyloid precursor protein gene. The Gly206Ala mutation was found in 8 of 19 unrelated Caribbean Hispanic families with early-onset familial AD. This genetic change may be a prevalent cause of early-onset familial AD in the Caribbean Hispanic population.

Quantitative neuropathological study of Alzheimer-type pathology in the hippocampus: comparison of senile dementia of Alzheimer type, senile dementia of Lewy body type, Parkinson's disease and non-demented elderly control patients.

PubMed

Ince, P; Irving, D; MacArthur, F; Perry, R H

1991-12-01

A Lewy body dementing syndrome in the elderly has been recently described and designated senile dementia of Lewy body type (SDLT) on the basis of a distinct clinicopathological profile. The pathological changes seen in SDLT include the presence of cortical Lewy bodies (LB) frequently, but not invariably, associated with senile plaque (SP) formation. Whilst neocortical neurofibrillary tangles (NFT) are sparse or absent, a proportion of these cases show involvement of the temporal archicortex by lesions comprising Alzheimer-type pathology (ATP, i.e. NFT, SP and granulovacuolar degeneration [GVD]). Thus the relationship between SDLT and senile dementia of Alzheimer type (SDAT) is complex and controversial. In this study quantitative neuropathology was used to compare the intensity and distribution of ATP in the hippocampus and entorhinal cortex of 53 patients from 3 disease groups (SDLT, SDAT, Parkinson's disease (PD)) and a group of neurologically and mentally normal elderly control patients. For most brain areas examined the extent of ATP between the patient groups followed the trend SDAT greater than SDLT greater than PD greater than control. Statistical comparison of these groups revealed significant differences between the mean densities of NFT, SP and GVD although individual cases showed considerable variability. These results confirm additional pathological differences between SDAT and SDLT regarding the intensity of involvement of the temporal archicortex by ATP. Many patients with Lewy body disorders (LBdis) show a predisposition to develop ATP albeit in a more restricted distribution (e.g. low or absent neocortical NFT) and at lower densities than is found in SDAT. Some cases of SDLT show minimal SP and NFT formation in both neocortex and archicortex supporting previously published data distinguishing this group from Alzheimer's disease.

Mutation analysis of the chromosome 14q24.3 dihydrolipoyl succinyltransferase (DLST) gene in patients with early-onset Alzheimer disease.

PubMed

Cruts, M; Backhovens, H; Van Gassen, G; Theuns, J; Wang, S Y; Wehnert, A; van Duijn, C M; Karlsson, T; Hofman, A; Adolfsson, R

1995-10-13

Linkage analysis studies have indicated that the chromosome band 14q24.3 harbours a major gene for familial early-onset Alzheimer's disease (AD). Recently we localized the chromosome 14 AD gene (AD3) in the 6.4 cM interval between the markers D14S289 and D14S61. We mapped the gene encoding dihydrolipoyl succinyltransferase (DLST), the E2k component of human alpha-ketoglutarate dehydrogenase complex (KGDHC), in the AD3 candidate region using yeast artificial chromosomes (YACs). The DLST gene is a candidate for the AD3 gene since deficiencies in KGDHC activity have been observed in brain tissue and fibroblasts of AD patients. The 15 exons and the promoter region of the DLST gene were analysed for mutations in chromosome 14 linked AD cases and in two series of unrelated early-onset AD cases (onset age < 55 years). Sequence variations in intronic sequences (introns 3, 5 and 10) or silent mutations in exonic sequences (exons 8 and 14) were identified. However, no AD related mutations were observed, suggesting that the DLST gene is not the chromosome 14 AD3 gene.

Cholesterol and Alzheimer Type Dementia among Adults with Down Syndrome

ERIC Educational Resources Information Center

Buckley, Frank

2008-01-01

This article reports a summary of research by Warren Zigman and colleagues investigating the link between cholesterol levels and Alzheimer type dementia among adults with Down syndrome. Warren Zigman and colleagues followed 123 adults with Down syndrome between May 1998 and April 2006. The participants were aged between 41 and 78 years at the…

Genomics of Alzheimer Disease: A Review.

PubMed

Rosenberg, Roger N; Lambracht-Washington, Doris; Yu, Gang; Xia, Weiming

2016-07-01

To provide a comprehensive review of knowledge of the genomics of Alzheimer disease (AD) and DNA amyloid β 42 (Aβ42) vaccination as a potential therapy. Genotype-phenotype correlations of AD are presented to provide a comprehensive appreciation of the spectrum of disease causation. Alzheimer disease is caused in part by the overproduction and lack of clearance of Aβ protein. Oligomer Aβ, the most toxic species of Aβ, causes direct injury to neurons, accompanied by enhanced neuroinflammation, astrocytosis and gliosis, and eventually neuronal loss. The strongest genetic evidence supporting this hypothesis derives from mutations in the amyloid precursor protein (APP) gene. A detrimental APP mutation at the β-secretase cleavage site linked to early-onset AD found in a Swedish pedigree enhances Aβ production, in contrast to a beneficial mutation 2 residues away in APP that reduces Aβ production and protects against the onset of sporadic AD. A number of common variants associated with late-onset AD have been identified including apolipoprotein E, BIN1, ABC7, PICALM, MS4A4E/MS4A6A, CD2Ap, CD33, EPHA1, CLU, CR1, and SORL1. One or 2 copies of the apolipoprotein E ε4 allele are a major risk factor for late-onset AD. With DNA Aβ42 vaccination, a Th2-type noninflammatory immune response was achieved with a downregulation of Aβ42-specific effector (Th1, Th17, and Th2) cell responses at later immunization times. DNA Aβ42 vaccination upregulated T regulator cells (CD4+, CD25+, and FoxP3+) and its cytokine interleukin 10, resulting in downregulation of T effectors. Mutations in APP and PS-1 and PS-2 genes that are associated with early-onset, autosomal, dominantly inherited AD, in addition to the at-risk gene polymorphisms responsible for late-onset AD, all indicate a direct and early role of Aβ in the pathogenesis of AD. A translational result of genomic research has been Aβ-reducing therapies including DNA Aβ42 vaccination as a promising approach to delay or

Molecular imaging of Alzheimer disease pathology.

PubMed

Kantarci, K

2014-06-01

Development of molecular imaging agents for fibrillar β-amyloid positron-emission tomography during the past decade has brought molecular imaging of Alzheimer disease pathology into the spotlight. Large cohort studies with longitudinal follow-up in cognitively normal individuals and patients with mild cognitive impairment and Alzheimer disease indicate that β-amyloid deposition can be detected many years before the onset of symptoms with molecular imaging, and its progression can be followed longitudinally. The utility of β-amyloid PET in the differential diagnosis of Alzheimer disease is greatest when there is no pathologic overlap between 2 dementia syndromes, such as in frontotemporal lobar degeneration and Alzheimer disease. However β-amyloid PET alone may be insufficient in distinguishing dementia syndromes that commonly have overlapping β-amyloid pathology, such as dementia with Lewy bodies and vascular dementia, which represent the 2 most common dementia pathologies after Alzheimer disease. The role of molecular imaging in Alzheimer disease clinical trials is growing rapidly, especially in an era when preventive interventions are designed to eradicate the pathology targeted by molecular imaging agents. © 2014 by American Journal of Neuroradiology.

Mutations of maturity-onset diabetes of the young (MODY) genes in Thais with early-onset type 2 diabetes mellitus.

PubMed

Plengvidhya, Nattachet; Boonyasrisawat, Watip; Chongjaroen, Nalinee; Jungtrakoon, Prapaporn; Sriussadaporn, Sutin; Vannaseang, Sathit; Banchuin, Napatawn; Yenchitsomanus, Pa-thai

2009-06-01

Six known genes responsible for maturity-onset diabetes of the young (MODY) were analysed to evaluate the prevalence of their mutations in Thai patients with MODY and early-onset type 2 diabetes. Fifty-one unrelated probands with early-onset type 2 diabetes, 21 of them fitted into classic MODY criteria, were analysed for nucleotide variations in promoters, exons, and exon-intron boundaries of six known MODY genes, including HNF-4alpha, GCK, HNF-1alpha, IPF-1, HNF-1beta, and NeuroD1/beta2, by the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) method followed by direct DNA sequencing. Missense mutations or mutations located in regulatory region, which were absent in 130 chromosomes of non-diabetic controls, were classified as potentially pathogenic mutations. We found that mutations of the six known MODY genes account for a small proportion of classic MODY (19%) and early-onset type 2 diabetes (10%) in Thais. Five of these mutations are novel including GCK R327H, HNF-1alpha P475L, HNF-1alphaG554fsX556, NeuroD1-1972 G > A and NeuroD1 A322N. Mutations of IPF-1 and HNF-1beta were not identified in the studied probands. Mutations of the six known MODY genes may not be a major cause of MODY and early-onset type 2 diabetes in Thais. Therefore, unidentified genes await discovery in a majority of Thai patients with MODY and early-onset type 2 diabetes.

A genomic scan for age at onset of Alzheimer's disease in 437 families from the NIMH Genetic Initiative.

PubMed

Dickson, M Ryan; Li, Jian; Wiener, Howard W; Perry, Rodney T; Blacker, Deborah; Bassett, Susan S; Go, Rodney C P

2008-09-05

We performed linkage analysis for age at onset (AAO) in the total Alzheimer's disease (AD) NIMH sample (N = 437 families). Families were subset as late-onset (320 families, AAO > or = 65) and early/mixed (117 families, at least 1 member with 50 < AAO < 65). Treating AAO as a censored trait, we obtained the gender and APOE adjusted residuals in a parametric survival model and analyzed the residuals as the quantitative trait (QT) in variance-component linkage analysis. For comparison, AAO-age at exam (AAE) was analyzed as the QT adjusting for affection status, gender, and APOE. Heritabilities for residual and AAO-AAE outcomes were 66.3% and 74.0%, respectively for the total sample, 56.0% and 57.0% in the late-onset sample, and 33.0% for both models in the early/mixed sample. The residual model yielded the largest peaks on chromosome 1 with LOD = 2.0 at 190 cM in the total set, LOD = 1.7 at 116 cM on chromosome 3 in the early/mixed subset, and LOD = 1.4 at 71 and 86 cM, respectively, on chromosome 6 in the late-onset subset. For the AAO-AAE outcome model the largest peaks were identified on chromosome 1 at 137 cM (LOD = 2.8) and chromosome 6 at 69 cM (LOD = 2.3) and 86 cM (LOD = 2.2) all in the late-onset subset. Additional peaks with LOD > or = 1 were identified on chromosomes 1, 2, 3, 6, 8, 9, 10, and 12 for the total sample and each subset. Results replicate previous findings, but identify additional suggestive peaks indicating the genetics of AAO in AD is complex with many chromosomal regions potentially containing modifying genes. 2008 Wiley-Liss, Inc.

Specific BACE1 genotypes provide additional risk for late-onset Alzheimer disease in APOE epsilon 4 carriers.

PubMed

Gold, Gabriel; Blouin, Jean-Louis; Herrmann, François R; Michon, Agnès; Mulligan, Reinhild; Duriaux Saïl, Geneviève; Bouras, Constantin; Giannakopoulos, Panteleimon; Antonarakis, Stylianos E

2003-05-15

Alzheimer disease (AD) is characterized neuropathologically by neurofibrillary tangles and senile plaques. A key component of plaques is A beta, a polypeptide derived from A beta-precursor protein (APP) through proteolytic cleavage catalyzed by beta and gamma-secretase. We hypothesized that sequence variation in genes BACE1 (on chromosome 11q23.3) and BACE2 (on chromosome 21q22.3), which encode two closely related proteases that seem to act as the APP beta-secretase, may represent a genetic risk factor for AD. We analyzed the frequencies of single nucleotide polymorphisms (SNPs) in BACE1 and BACE2 genes in a community-based sample of 96 individuals with late-onset AD and 170 controls selected randomly among residents of the same community. The genotype data in both study groups did not demonstrate any association between AD and BACE1 or BACE2. After stratification for APOE status, however, an association between a BACE1 polymorphism located within codon V262 and AD in APOE epsilon 4 carriers was observed (P = 0.03). We conclude that sequence variation in the BACE1 or BACE 2 gene is not a significant risk factor for AD; however, a combination of a specific BACE1 allele and APOE epsilon 4 may increase the risk for Alzheimer disease over and above that attributed to APOE epsilon 4 alone. Copyright 2003 Wiley-Liss, Inc.

Phenotypic characteristics of Alzheimer patients carrying an ABCA7 mutation.

PubMed

Van den Bossche, Tobi; Sleegers, Kristel; Cuyvers, Elise; Engelborghs, Sebastiaan; Sieben, Anne; De Roeck, Arne; Van Cauwenberghe, Caroline; Vermeulen, Steven; Van den Broeck, Marleen; Laureys, Annelies; Peeters, Karin; Mattheijssens, Maria; Vandenbulcke, Mathieu; Vandenberghe, Rik; Martin, Jean-Jacques; De Deyn, Peter P; Cras, Patrick; Van Broeckhoven, Christine

2016-06-07

To generate a clinical and pathologic phenotype of patients carrying rare loss-of-function mutations in ABCA7, identified in a Belgian Alzheimer patient cohort and in an autosomal dominant family. We performed a retrospective review of available data records, medical records, results of CSF analyses and neuroimaging studies, and neuropathology data. The mean onset age of the mutation carriers (n = 22) was 73.4 ± 8.4 years with a wide age range of 36 (54-90) years, which was independent of APOE genotype and cerebrovascular disease. The mean disease duration was 5.7 ± 3.0 years (range 2-12 years). A positive family history was recorded for 10 carriers (45.5%). All patient carriers except one presented with memory complaints. The 4 autopsied brains showed typical immunohistochemical changes of late-onset Alzheimer disease. All patients carrying a loss-of-function mutation in ABCA7 exhibited a classical Alzheimer disease phenotype, though with a striking wide onset age range, suggesting the influence of unknown modifying factors. © 2016 American Academy of Neurology.

Phenotypic characteristics of Alzheimer patients carrying an ABCA7 mutation

PubMed Central

Van den Bossche, Tobi; Sleegers, Kristel; Cuyvers, Elise; Engelborghs, Sebastiaan; Sieben, Anne; De Roeck, Arne; Van Cauwenberghe, Caroline; Vermeulen, Steven; Van den Broeck, Marleen; Laureys, Annelies; Peeters, Karin; Mattheijssens, Maria; Vandenbulcke, Mathieu; Vandenberghe, Rik; Martin, Jean-Jacques; De Deyn, Peter P.; Cras, Patrick

2016-01-01

Objective: To generate a clinical and pathologic phenotype of patients carrying rare loss-of-function mutations in ABCA7, identified in a Belgian Alzheimer patient cohort and in an autosomal dominant family. Methods: We performed a retrospective review of available data records, medical records, results of CSF analyses and neuroimaging studies, and neuropathology data. Results: The mean onset age of the mutation carriers (n = 22) was 73.4 ± 8.4 years with a wide age range of 36 (54–90) years, which was independent of APOE genotype and cerebrovascular disease. The mean disease duration was 5.7 ± 3.0 years (range 2–12 years). A positive family history was recorded for 10 carriers (45.5%). All patient carriers except one presented with memory complaints. The 4 autopsied brains showed typical immunohistochemical changes of late-onset Alzheimer disease. Conclusions: All patients carrying a loss-of-function mutation in ABCA7 exhibited a classical Alzheimer disease phenotype, though with a striking wide onset age range, suggesting the influence of unknown modifying factors. PMID:27037232

A patient with Alzheimer's disease complicated by elderly-onset Cushing's syndrome who had undergone surgical treatment for adrenocorticotropic hormone-independent macronodular adrenal hyperplasia.

PubMed

Haraguchi, Yoshinori; Mizoguchi, Yoshito; Noguchi, Tomoyuki; Arai, Takeo; Fukuyama, Junko; Kato, Takahiro A; Kawashima, Toshiro; Monji, Akira

2016-07-01

Cushing's syndrome (CS) is a rare disorder, especially in older people. Loss of brain volume and neurocognitive impairment of varying degrees has been demonstrated in patients with CS. However, there is a large difference between the median age of presentation of CS and that of Alzheimer's disease. We herein report a case of a patient with Alzheimer's disease complicated by elderly-onset CS who had undergone surgical treatment for adrenal hyperplasia. Surgical correction of hypercortisolism seems to have slowed the progression of brain volume loss and cognitive dysfunction and improved psychiatric symptoms such as visual hallucination, restlessness, and psychomotor excitement. These improvements have remarkably reduced the burden on the patient's caregivers. The present case suggests that subclinical CS may be present, particularly in rapidly progressive dementia, and that surgical treatment of CS for neuropsychiatric symptoms is useful. © 2015 The Authors. Psychogeriatrics © 2015 Japanese Psychogeriatric Society.

Distinguishing neurocognitive deficits in adult patients with NP-C from early onset Alzheimer's dementia.

PubMed

Johnen, Andreas; Pawlowski, Matthias; Duning, Thomas

2018-06-05

Niemann-Pick disease type C (NP-C) is a rare, progressive neurodegenerative disease caused by mutations in the NPC1 or the NPC2 gene. Neurocognitive deficits are common in NP-C, particularly in patients with the adolescent/adult-onset form. As a disease-specific therapy is available, it is important to distinguish clinically between the cognitive profiles in NP-C and primary dementia (e.g., early Alzheimer's disease; eAD). In a prospective observational study, we directly compared the neurocognitive profiles of patients with confirmed NP-C (n = 7) and eAD (n = 15). All patients underwent neurocognitive assessment using dementia screening tests (mini-mental status examination [MMSE] and frontal assessment battery [FAB]) and an extensive battery of tests assessing verbal memory, visuoconstructive abilities, visual memory, executive functions and verbal fluency. Overall cognitive impairment (MMSE) was significantly greater in eAD vs. NP-C (p = 0.010). The frequency of patients classified as cognitively 'impaired' was also significantly greater in eAD vs. NP-C (p = 0.025). Patients with NP-C showed relatively preserved verbal memory, but frequent impairment in visual memory, visuoconstruction, executive functions and in particular, verbal fluency. In the eAD group, a wider profile of more frequent and more severe neurocognitive deficits was seen, primarily featuring severe verbal and visual memory deficits along with major executive impairment. Delayed verbal memory recall was a particularly strong distinguishing factor between the two groups. A combination of detailed yet easy-to-apply neurocognitive tests assessing verbal memory, executive functions and verbal fluency may help distinguish NP-C cases from those with primary dementia due to eAD.

Survival after initial diagnosis of Alzheimer disease.

PubMed

Larson, Eric B; Shadlen, Marie-Florence; Wang, Li; McCormick, Wayne C; Bowen, James D; Teri, Linda; Kukull, Walter A

2004-04-06

Alzheimer disease is an increasingly common condition in older people. Knowledge of life expectancy after the diagnosis of Alzheimer disease and of associations of patient characteristics with survival may help planning for future care. To investigate the course of Alzheimer disease after initial diagnosis and examine associations hypothesized to correlate with survival among community-dwelling patients with Alzheimer disease. Prospective observational study. An Alzheimer disease patient registry from a base population of 23 000 persons age 60 years and older in the Group Health Cooperative, Seattle, Washington. 521 newly recognized persons with Alzheimer disease enrolled from 1987 to 1996 in an Alzheimer disease patient registry. Baseline measurements included patient demographic features, Mini-Mental State Examination score, Blessed Dementia Rating Scale score, duration since reported onset of symptoms, associated symptoms, comorbid conditions, and selected signs. Survival was the outcome of interest. The median survival from initial diagnosis was 4.2 years for men and 5.7 years for women with Alzheimer disease. Men had poorer survival across all age groups compared with females. Survival was decreased in all age groups compared with the life expectancy of the U.S. population. Predictors of mortality based on proportional hazards models included a baseline Mini-Mental State Examination score of 17 or less, baseline Blessed Dementia Rating Scale score of 5.0 or greater, presence of frontal lobe release signs, presence of extrapyramidal signs, gait disturbance, history of falls, congestive heart failure, ischemic heart disease, and diabetes at baseline. The base population, although typical of the surrounding Seattle community, may not be representative of other, more diverse populations. In this sample of community-dwelling elderly persons who received a diagnosis of Alzheimer disease, survival duration was shorter than predicted on the basis of U.S. population

Association of GWAS Top Genes With Late-Onset Alzheimer's Disease in Colombian Population.

PubMed

Moreno, Diana Jennifer; Ruiz, Susana; Ríos, Ángela; Lopera, Francisco; Ostos, Henry; Via, Marc; Bedoya, Gabriel

2017-02-01

The association of variants in CLU, CR1, PICALM, BIN1, ABCA7, and CD33 genes with late-onset Alzheimer's disease (LOAD) was evaluated and confirmed through genome-wide association study. However, it is unknown whether these associations can be replicated in admixed populations. The association of 14 single-nucleotide polymorphisms in those genes was evaluated in 280 LOAD cases and 357 controls from the Colombian population. In a multivariate analysis using age, gender, APOE∊4 status, and admixture covariates, significant associations were obtained ( P < .05) for variants in BIN1 (rs744373, odds ratio [OR]: 1.42), CLU (rs11136000, OR: 0.66), PICALM (rs541458, OR: 0.69), ABCA7 (rs3764650, OR: 1.7), and CD33 (rs3865444, OR: 1.12). Likewise, a significant interaction effect was observed between CLU and CR1 variants with APOE. This study replicated the associations previously reported in populations of European ancestry and shows that APOE variants have a regulatory role on the effect that variants in other loci have on LOAD, reflecting the importance of gene-gene interactions in the etiology of neurodegenerative diseases.

Alzheimer's Disease: The Role of Microglia in Brain Homeostasis and Proteopathy

PubMed Central

Clayton, Kevin A.; Van Enoo, Alicia A.; Ikezu, Tsuneya

2017-01-01

Brain aging is central to late-onset Alzheimer's disease (LOAD), although the mechanisms by which it occurs at protein or cellular levels are not fully understood. Alzheimer's disease is the most common proteopathy and is characterized by two unique pathologies: senile plaques and neurofibrillary tangles, the former accumulating earlier than the latter. Aging alters the proteostasis of amyloid-β peptides and microtubule-associated protein tau, which are regulated in both autonomous and non-autonomous manners. Microglia, the resident phagocytes of the central nervous system, play a major role in the non-autonomous clearance of protein aggregates. Their function is significantly altered by aging and neurodegeneration. This is genetically supported by the association of microglia-specific genes, TREM2 and CD33, and late onset Alzheimer's disease. Here, we propose that the functional characterization of microglia, and their contribution to proteopathy, will lead to a new therapeutic direction in Alzheimer's disease research. PMID:29311768

Identification of PSEN2 mutation p.N141I in Argentine pedigrees with early-onset familial Alzheimer's disease.

PubMed

Muchnik, Carolina; Olivar, Natividad; Dalmasso, María Carolina; Azurmendi, Pablo Javier; Liberczuk, Cynthia; Morelli, Laura; Brusco, Luis Ignacio

2015-10-01

Presenilin 2 gene (PSEN2) mutations account for <5% of all early-onset familial Alzheimer's disease (EOFAD) cases and only 13 have strong evidence for pathogenicity. We aimed to investigate the presence of PSEN2 mutation p.N141I and characterize the clinical phenotypes in 2 Argentine pedigrees (AR2 and AR3) with clinical symptoms of EOFAD. Detailed clinical assessments and genetic screening for PSEN2 and APOE genes were carried out in 19 individuals of AR2 and AR3 families. The p.N141I mutation was identified in all affected subjects and was associated with prominent early onset, rapidly progressive dementia, neurologic, and behavioral symptoms. AR2 and AR3 families share the same Volga German ancestry as all the families reported presenting this mutation. To our knowledge, this is the first report of PSEN2 mutation p.N141I in Argentina and even more, in South America. Our contribution increases the total number of described families carrying this mutation and help to improve the characterization of clinical phenotype in EOFAD associated to PSEN2 mutations. Copyright © 2015 Elsevier Inc. All rights reserved.

Fatty aspirin: a new perspective in the prevention of dementia of Alzheimer's type?

PubMed

Pomponi, M; Di Gioia, A; Bria, P; Pomponi, M F L

2008-10-01

Alzheimer's disease (AD) leads to a dramatic decline in cognitive abilities and memory. A more modest disruption of memory often occurs in normal aging and the same circuits that are devastated through degeneration in AD are vulnerable to sub-lethal age-related changes that alter synaptic transmission. There are numerous indications that aberrant plasticity is critically involved in Alzheimer's. Is ageing itself the major risk factor for AD? Is AD an acceleration of normal ageing? We assume that the ability of the brain is to modify its own structural organization and functioning which is liable to become impaired in ageing until it becomes dramatically impaired in Alzheimer's. Moreover, ageing can compromise the conversion of dietary alpha-linolenic acid (ALA) to docosahexaenoic acid (DHA). DHA regulates synaptogenesis and affects the synaptic structure, and synapse density is reduced in ageing. DHA and newly identified DHA-derived messenger, neuroprotecting D1 (NPD1), protect synapses and decrease the number of activated microglia in the hippocampal system. Delaying AD onset by a few years would reduce the number of the cases of dementia in the community. DHA (and NPD1?) and aspirin induce brain-derived neurotrophic factor (BDNF) protein expression and this protein has a crucial role in neuronal survival. The authors--in view of the increased neuroinflammatory reaction frequently observed during normal brain ageing--suggest the long-term use of "fatty aspirin", an association of DHA and/or NPD1 and aspirin (or nitroaspirin), to postpone, or prevent, the structural neurodegeneration of the brain.

Fine mapping of the chromosome 12 late-onset Alzheimer disease locus: potential genetic and phenotypic heterogeneity.

PubMed

Scott, W K; Grubber, J M; Conneally, P M; Small, G W; Hulette, C M; Rosenberg, C K; Saunders, A M; Roses, A D; Haines, J L; Pericak-Vance, M A

2000-03-01

Apolipoprotein E (APOE) is the only confirmed susceptibility gene for late-onset Alzheimer disease (AD). In a recent genomic screen of 54 families with late-onset AD, we detected significant evidence for a second late-onset AD locus located on chromosome 12 between D12S373 and D12S390. Linkage to this region was strongest in 27 large families with at least one affected individual without an APOE-4 allele, suggesting that APOE and the chromosome 12 locus might have independent effects. We have since genotyped several additional markers across the region, to refine the linkage results. In analyzing these additional data, we have addressed the issue of heterogeneity in the data set by weighting results by clinical and neuropathologic features, sibship size, and APOE genotype. When considering all possible affected sib pairs (ASPs) per nuclear family, we obtained a peak maximum LOD score between D12S1057 and D12S1042. The magnitude and location of the maximum LOD score changed when different weighting schemes were used to control for the number of ASPs contributed by each nuclear family. Using the affected-relative-pair method implemented in GENEHUNTER-PLUS, we obtained a maximum LOD score between D12S398 and D12S1632, 25 cM from the original maximum LOD score. These results indicate that family size influences the location estimate for the chromosome 12 AD gene. The results of conditional linkage analysis by use of GENEHUNTER-PLUS indicated that evidence for linkage to chromosome 12 was stronger in families with affected individuals lacking an APOE-4 allele; much of this evidence came from families with affected individuals with neuropathologic diagnosis of dementia with Lewy bodies (DLB). Taken together, these results indicate that the chromosome 12 locus acts independently of APOE to increase the risk of late-onset familial AD and that it may be associated with the DLB variant of AD.

Apolipoprotein E in the genetics and epidemiology of Alzheimer`s disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hardy, J.

1995-10-09

The role of apolipoprotein E (ApoE) alleles and isoforms in the etiology and pathogenesis of Alzheimer`s disease is discussed. The possibility that ApoE itself is not involved in the disease pathogenesis but is merely in genetic disequilibrium with the real locus is discussed and dismissed. The data showing that the {epsilon}4 allele is associated with an increased risk of developing the disease and with an earlier onset age are reviewed. The data showing that, at least in some circumstances, the {epsilon}2 allele is associated with a decrease in the risk of developing the disease, and with a later onset agemore » are also reviewed. Data from the genetic analysis of other disorders are reviewed and presented, and it is suggested that the genetic data support the notion that the role of ApoE in the etiology of the disease directly relates to {beta}-amyloid deposition and plaque formation. This suggestion is in concordance with the most likely mechanism for the role of P-amyloid precursor protein gene mutations as other risk factors for the disease. 68 refs.« less

Butyrylcholinesterase K and Apolipoprotein E-ɛ4 Reduce the Age of Onset of Alzheimer's Disease, Accelerate Cognitive Decline, and Modulate Donepezil Response in Mild Cognitively Impaired Subjects.

PubMed

De Beaumont, Louis; Pelleieux, Sandra; Lamarre-Théroux, Louise; Dea, Doris; Poirier, Judes

2016-10-04

Genetic heterogeneity in amnestic mild cognitively impaired (aMCI) subjects could lead to variations in progression rates and response to cholinomimetic agents. Together with the apolipoprotein E4 (APOE-ɛ4) gene, butyrylcholinesterase (BCHE) has become recently one of the few Alzheimer's disease (AD) susceptibility genes with distinct pharmacogenomic properties. To validate candidate genes (APOE/BCHE) which display associations with age of onset of AD and donepezil efficacy in aMCI subjects. Using the Petersen et al. (2005) study on vitamin E and donepezil efficacy in aMCI, we contrasted the effects of BCHE and APOE variants on donepezil drug response using the Alzheimer's Disease Assessment Score-Cognition (ADAS-Cog) scale. Independently, we assessed the effects of APOE/BCHE genotypes on age of onset and cortical choline acetyltransferase activity in autopsy-confirmed AD and age-matched control subjects. Statistical analyses revealed a significant earlier age of onset in AD for APOE-ɛ4, BCHE-K*, and APOE-ɛ4/BCHE-K* carriers. Among the carriers of APOE-ɛ4 and BCHE-K*, the benefit of donepezil was evident at the end of the three-year follow-up. The responder's pharmacogenomic profile is consistent with reduced brain cholinergic activity measured in APOE-ɛ4 and BCHE-K* positive subjects. APOE-ɛ4 and BCHE-K* positive subjects display an earlier age of onset of AD, an accelerated cognitive decline and a greater cognitive benefits to donepezil therapy. These results clearly emphasize the necessity of monitoring potential pharmacogenomic effects in this population of subjects, and suggest enrichment strategies for secondary prevention trials involving prodromal AD subjects.

Pharmacologic management of Alzheimer disease.

PubMed

Downey, Deborah

2008-02-01

Although the diagnosis of AD can be devastating, treatment options exist that can slow the disease's progression and allow patients to continue performing ADLs, thereby improving the quality of life for both patient and caregiver. Research is ongoing, and it is estimated by the Alzheimer's Association that finding a treatment that could delay onset by only 5 years could reduce the number of individuals with AD by nearly 50% over the next 50 years (Alzheimer's Association, 2007). Although pharmacotherapy is not yet a cure, it does remain an important part of a total approach to caring for patients and families affected by AD.

Recruitment of subjects into clinical trials for Alzheimer disease.

PubMed

Knebl, Janice A; Patki, Deepti

2010-09-01

Alzheimer disease is a devastating neurodegenerative disorder affecting millions of Americans. It reduces the ability of the individual to remain independent, places a burden on caregivers, and substantially increases healthcare costs. New treatments are being tested in numerous clinical trials with the goal of preventing or delaying the onset of Alzheimer disease, slowing or modifying the disease's course, or finding a cure for patients with the disease. Alzheimer disease research can successfully proceed only if individuals who have this illness are willing to participate in clinical trials. However, recruitment and retention of subjects in clinical trials for Alzheimer disease is a challenging task. Furthermore, because of reductions in decision-making capacities of individuals with Alzheimer disease, clinical trials also need to involve caregivers. The present article delineates unique hurdles encountered in the recruitment process for Alzheimer disease clinical trials. The article also identifies strategies for effective recruitment of subjects in Alzheimer disease clinical trials, including guidelines to help principal investigators and clinical research coordinators reach recruitment goals.

Delayed-onset dementia after stroke or transient ischemic attack.

PubMed

Mok, Vincent C T; Lam, Bonnie Y K; Wang, Zhaolu; Liu, Wenyan; Au, Lisa; Leung, Eric Y L; Chen, Sirong; Yang, Jie; Chu, Winnie C W; Lau, Alexander Y L; Chan, Anne Y Y; Shi, Lin; Fan, Florence; Ma, Sze H; Ip, Vincent; Soo, Yannie O Y; Leung, Thomas W H; Kwok, Timothy C Y; Ho, Chi L; Wong, Lawrence K S; Wong, Adrian

2016-11-01

Patients surviving stroke without immediate dementia are at high risk of delayed-onset dementia. Mechanisms underlying delayed-onset dementia are complex and may involve vascular and/or neurodegenerative diseases. Dementia-free patients with stroke and/or transient ischemic attack (TIA; n = 919) were studied for 3 years prospectively, excluding those who developed dementia 3 to 6 months after stroke and/or TIA. Forty subjects (4.4%) developed dementia during the study period. Imaging markers of severe small vessel disease (SVD), namely presence of ≥3 lacunes and confluent white matter changes; history of hypertension and diabetes mellitus independently predicted delayed-onset dementia after adjustment for age, gender, and education. Only 6 of 31 (19.4%) subjects with delayed cognitive decline harbored Alzheimer's disease-like Pittsburg compound B (PiB) retention. Most PiB cases (16/25, 64%) had evidence of severe SVD. Severe SVD contributes importantly to delayed-onset dementia after stroke and/or TIA. Future clinical trials aiming to prevent delayed-onset dementia after stroke and/or TIA should target this high-risk group. Copyright © 2016 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Therapeutic effect of mesenchymal multipotent stromal cells on memory in animals with Alzheimer-type neurodegeneration.

PubMed

Bobkova, N V; Poltavtseva, R A; Samokhin, A N; Sukhikh, G T

2013-11-01

Transplantation of human mesenchymal multipotent stromal cells improved spatial memory in bulbectomized mice with Alzheimer-type neurodegeneration. The positive effect was observed in 1 month after intracerebral transplantation and in 3 months after systemic injection of mesenchymal multipotent stromal cells. No cases of malignant transformation were noted. These findings indicate prospects of using mesenchymal multipotent stromal cells for the therapy of Alzheimer disease and the possibility of their systemic administration for attaining the therapeutic effect.

Comparing different types of source memory attributes in dementia of Alzheimer's type.

PubMed

Mammarella, Nicola; Fairfield, Beth; Di Domenico, Alberto

2012-04-01

Source monitoring (SM) refers to our ability to discriminate between memories from different sources. Twenty healthy high-cognitive functioning older adults, 20 healthy low-cognitive functioning older adults, and 20 older adults with dementia of Alzheimer's type (DAT) were asked to perform a series of SM tasks that varied in terms of the to-be-remembered source attribute (perceptual, spatial, temporal, semantic, social, and affective details). Results indicated that older DAT adults had greater difficulty in SM compared to the healthy control groups, especially with spatial and semantic details. Data are discussed in terms of the SM framework and suggest that poor memory for some types of source information may be considered as an important indicator of clinical memory function when assessing for the presence and severity of dementia.

[A case report of early-onset Alzheimer's disease with multiple psychotic symptoms, finally diagnosed as APPV717I mutation by genetic testing].

PubMed

Ishimaru, Takashi; Ochi, Shinichiro; Matsumoto, Teruhisa; Yoshida, Taku; Abe, Masao; Toyota, Yasutaka; Fukuhara, Ryuji; Tanimukai, Satoshi; Ueno, Shu-ichi

2013-01-01

It is difficult to confirm a diagnosis of early-onset Alzheimer's disease (EOAD) because patients sometimes have non-specific cortical features, such as psychiatric symptoms, executive functional impairment, and pyramidal symptoms, along with typical symptoms, such as recent memory impairment and disorientation. We encountered a patient with multiple psychotic symptoms, finally diagnosed with EOAD on genetic testing. A right-handed sixty-year-old man, whose mother was suspected of having dementia, developed memory impairment at the age of fifty, disorientation at the age of fifty-six, and both visual hallucination and dressing apraxia at the age of fifty-nine. After admission to a psychiatric hospital for treatment, his symptoms disappeared with antipsychotic medication. However, his ADL were declining and so he was referred to our university hospital. He had frontal lobe symptoms, pyramidal signs, and extrapyramidal signs with severe dementia. Neuropsychological examinations were not possible because of sedation. On brain MRI, he showed diffuse atrophy of the cerebral cortex and hippocampus. HMPO-SPECT showed hypoperfusion of cerebral cortices diffusely. We decided to perform genetic testing because he had both family and alcohol abuse histories. He showed EOAD with V717I mutation of the amyloid precursor protein gene. After the discontinuation of antipsychotics, excessive sedation and extrapyramidal signs disappeared. A dose of 10 mg of donepezil was effective to improve motivation and activity, and his mini mental examination score was calculable after recovery. The case supports usefulness of applying genetic testing for Alzheimer's disease to patients with early onset dementia, even when they do not have a family history.

Influence of family history of dementia in the development and progression of late-onset Alzheimer's disease.

PubMed

Scarabino, Daniela; Gambina, Giuseppe; Broggio, Elisabetta; Pelliccia, Franca; Corbo, Rosa Maria

2016-03-01

Family history of dementia (FH) is a recognized risk factor for developing late-onset Alzheimer's disease (AD). We asked whether having FH increases AD risk and influences disease severity (age at onset and cognitive impairment) in 420 AD patients and 109 controls with (FH+) or without (FH-). The relationships of APOE and other AD risk genes with FH were analyzed as well. The proportion of APOE e4 allele carriers was higher among the FH+ than the FH- AD patients (49.6% vs. 38.9%; P = 0.04). The distribution of the risk genotypes of nine AD susceptibility genes previously examined (CHAT, CYP17, CYP19, ESR1, FSHR, P53, P73, P21, PPARG) did not differ between the FH+ and the FH- AD patients, indicating that none contributed significantly to familial clustering of disease. FH was associated with an increased AD risk (odds ratio [OR] 2.71, 95% confidence interval [CI] 1.44-5.09; P = 0.002) independent of carrying the APOE e4 allele (OR 2.61, 95%CI 1.53-4.44; P = 0.0004). Having a first-degree relative or a parent with dementia was significantly associated with AD risk (OR 2.9, 95%CI 1.3-6.4; P = 0.009 and OR 2.7, 95%CI 1.1-6.2; P = 0.02) but having a sibling with dementia was not (OR 1.7, 95%CI 0.2 to 14.7; P = 0.6). Among the FH+ AD patients, having one or both parents affected seemed to raise the risk of earlier onset age (P = 0.02) and greater cognitive impairment (P = 0.02) than having only an affected sibling, whereas having two or more affected relatives did not. © 2015 Wiley Periodicals, Inc.

Edaravone alleviates Alzheimer's disease-type pathologies and cognitive deficits.

PubMed

Jiao, Shu-Sheng; Yao, Xiu-Qing; Liu, Yu-Hui; Wang, Qing-Hua; Zeng, Fan; Lu, Jian-Jun; Liu, Jia; Zhu, Chi; Shen, Lin-Lin; Liu, Cheng-Hui; Wang, Ye-Ran; Zeng, Gui-Hua; Parikh, Ankit; Chen, Jia; Liang, Chun-Rong; Xiang, Yang; Bu, Xian-Le; Deng, Juan; Li, Jing; Xu, Juan; Zeng, Yue-Qin; Xu, Xiang; Xu, Hai-Wei; Zhong, Jin-Hua; Zhou, Hua-Dong; Zhou, Xin-Fu; Wang, Yan-Jiang

2015-04-21

Alzheimer's disease (AD) is one of most devastating diseases affecting elderly people. Amyloid-β (Aβ) accumulation and the downstream pathological events such as oxidative stress play critical roles in pathogenesis of AD. Lessons from failures of current clinical trials suggest that targeting multiple key pathways of the AD pathogenesis is necessary to halt the disease progression. Here we show that Edaravone, a free radical scavenger that is marketed for acute ischemic stroke, has a potent capacity of inhibiting Aβ aggregation and attenuating Aβ-induced oxidation in vitro. When given before or after the onset of Aβ deposition via i.p. injection, Edaravone substantially reduces Aβ deposition, alleviates oxidative stress, attenuates the downstream pathologies including Tau hyperphosphorylation, glial activation, neuroinflammation, neuronal loss, synaptic dysfunction, and rescues the behavioral deficits of APPswe/PS1 mice. Oral administration of Edaravone also ameliorates the AD-like pathologies and memory deficits of the mice. These findings suggest that Edaravone holds a promise as a therapeutic agent for AD by targeting multiple key pathways of the disease pathogenesis.

New Alzheimer's disease locus on chromosome 8.

PubMed

Giedraitis, V; Hedlund, M; Skoglund, L; Blom, E; Ingvast, S; Brundin, R; Lannfelt, L; Glaser, A

2006-12-01

Family history is one of the most consistent risk factors for dementia. Therefore, analysis of families with a distinct inheritance pattern of disease can be a powerful approach for the identification of previously unknown disease genes. To map susceptibility regions for Alzheimer's disease. A complete genome scan with 369 microsatellite markers was carried out in 12 extended families collected in Sweden. Age at disease onset ranged from 53 to 78 years, but in 10 of the families there was at least one member with age at onset of < or =65 years. Mutations in known early-onset Alzheimer's disease susceptibility genes have been excluded. All people were genotyped for APOE, but no clear linkage with the epsilon4 allele was observed. Although no common disease locus could be found in all families, in two families an extended haplotype was identified on chromosome 8q shared by all affected members. In one of the families, a non-parametric multimarker logarithm of the odds (LOD) score of 4.2 (p = 0.004) was obtained and analysis based on a dominant model showed a parametric LOD score of 2.4 for this region. All six affected members of this family shared a haplotype of 10 markers spanning about 40 cM. Three affected members in another family also shared a haplotype in the same region. On the basis of our data, we propose the existence of a dominantly acting Alzheimer's disease susceptibility locus on chromosome 8.

CDK5RAP2 gene and tau pathophysiology in late-onset sporadic Alzheimer's disease.

PubMed

Miron, Justin; Picard, Cynthia; Nilsson, Nathalie; Frappier, Josée; Dea, Doris; Théroux, Louise; Poirier, Judes

2018-06-01

Because currently known Alzheimer's disease (AD) single-nucleotide polymorphisms only account for a small fraction of the genetic variance in this disease, there is a need to identify new variants associated with AD. Our team performed a genome-wide association study in the Quebec Founder Population isolate to identify novel protective or risk genetic factors for late-onset sporadic AD and examined the impact of these variants on gene expression and AD pathology. The rs10984186 variant is associated with an increased risk of developing AD and with a higher CDK5RAP2 mRNA prevalence in the hippocampus. On the other hand, the rs4837766 variant, which is among the best cis-expression quantitative trait loci in the CDK5RAP2 gene, is associated with lower mild cognitive impairment/AD risk and conversion rate. The rs10984186 risk and rs4837766 protective polymorphic variants of the CDK5RAP2 gene might act as potent genetic modifiers for AD risk and/or conversion by modulating the expression of this gene. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Rapamycin rescues vascular, metabolic and learning deficits in apolipoprotein E4 transgenic mice with pre-symptomatic Alzheimer's disease.

PubMed

Lin, Ai-Ling; Jahrling, Jordan B; Zhang, Wei; DeRosa, Nicholas; Bakshi, Vikas; Romero, Peter; Galvan, Veronica; Richardson, Arlan

2017-01-01

Apolipoprotein E ɛ4 allele is a common susceptibility gene for late-onset Alzheimer's disease. Brain vascular and metabolic deficits can occur in cognitively normal apolipoprotein E ɛ4 carriers decades before the onset of Alzheimer's disease. The goal of this study was to determine whether early intervention using rapamycin could restore neurovascular and neurometabolic functions, and thus impede pathological progression of Alzheimer's disease-like symptoms in pre-symptomatic Apolipoprotein E ɛ4 transgenic mice. Using in vivo, multimodal neuroimaging, we found that apolipoprotein E ɛ4 mice treated with rapamycin had restored cerebral blood flow, blood-brain barrier integrity and glucose metabolism, compared to age- and gender-matched wild-type controls. The preserved vasculature and metabolism were associated with amelioration of incipient learning deficits. We also found that rapamycin restored the levels of the proinflammatory cyclophilin A in vasculature, which may contribute to the preservation of cerebrovascular function in the apolipoprotein E ɛ4 transgenics. Our results show that rapamycin improves functional outcomes in this mouse model and may have potential as an effective intervention to block progression of vascular, metabolic and early cognitive deficits in human Apolipoprotein E ɛ4 carriers. As rapamycin is FDA-approved and neuroimaging is readily used in humans, the results of the present study may provide the basis for future Alzheimer's disease intervention studies in human subjects. © The Author(s) 2015.

[Connections between sleep and Alzheimer's disease : Insomnia, amnesia and amyloid].

PubMed

Busche, M A; Kekuš, M; Förstl, H

2017-03-01

Sleep plays an essential role in memory consolidation. Although sleep problems are common in Alzheimer's disease, they are not usually thought to be key features of the disease; however, new experimental research has shown that sleep disturbances not only occur before the onset of typical cognitive deficits but are also associated with the pathogenesis of Alzheimer's disease and may have a decisive influence on the symptoms and course. Thus, sleep disturbances may be potentially modifiable risk factors for Alzheimer's disease that deserve more attention in research, diagnostics and treatment.

Linkage and association study of late-onset Alzheimer disease families linked to 9p21.3.

PubMed

Züchner, S; Gilbert, J R; Martin, E R; Leon-Guerrero, C R; Xu, P-T; Browning, C; Bronson, P G; Whitehead, P; Schmechel, D E; Haines, J L; Pericak-Vance, M A

2008-11-01

A chromosomal locus for late-onset Alzheimer disease (LOAD) has previously been mapped to 9p21.3. The most significant results were reported in a sample of autopsy-confirmed families. Linkage to this locus has been independently confirmed in AD families from a consanguineous Israeli-Arab community. In the present study we analyzed an expanded clinical sample of 674 late-onset AD families, independently ascertained by three different consortia. Sample subsets were stratified by site and autopsy-confirmation. Linkage analysis of a dense array of SNPs across the chromosomal locus revealed the most significant results in the 166 autopsy-confirmed families of the NIMH sample. Peak HLOD scores of 4.95 at D9S741 and 2.81 at the nearby SNP rs2772677 were obtained in a dominant model. The linked region included the cyclin-dependent kinase inhibitor 2A gene (CDKN2A), which has been suggested as an AD candidate gene. By re-sequencing all exons in the vicinity of CDKN2A in 48 AD cases, we identified and genotyped four novel SNPs, including a non-synonymous, a synonymous, and two variations located in untranslated RNA sequences. Family-based allelic and genotypic association analysis yielded significant results in CDKN2A (rs11515: PDT p = 0.003, genotype-PDT p = 0.014). We conclude that CDKN2A is a promising new candidate gene potentially contributing to AD susceptibility on chromosome 9p.

Circadian wheel running behavior is altered in an APP/E4 mouse model of late onset Alzheimer's disease.

PubMed

Boggs, Katelyn N; Kakalec, Peter A; Smith, Meghann L; Howell, Stefanie N; Flinn, Jane M

2017-12-01

Circadian rhythms are altered in several diseases associated with aging, one of which is Alzheimer's disease (AD). One example of a circadian rhythm is the rest-activity cycle, which can be measured in mice by monitoring their wheel-running. The present study sought to investigate differences in light phase/dark phase activity between a mouse model of late onset AD (APP/E4) and control (C57Bl6J) mice, in both the pre-plaque and post-plaques stages of the disease. To assess activity level, 24-h wheel running behavior was monitored at six months (pre-plaque) and twelve months (post-plaque) for a period of nine days. The following measures were analyzed: counts (wheel rotations) during the dark phase, counts during the light phase, hour of activity onset, and hour of activity offset. Key findings indicate that activity onset is delayed in APP/E4 mice at six and twelve months, and activity profiles for APP/E4 and C57Bl6J mice differ during the light and dark phase in such a way that APP/E4 mice run less in the early hours of the dark phase and more in the later hours of the dark phase compared to C57Bl6J mice. These findings imply that rest-activity cycle is altered in the pre-plaque stages of AD in APP/E4 mice, as they show impairments as early as six months of age. Copyright © 2017 Elsevier Inc. All rights reserved.

Order and Disorder in Conversation: Encounters with Dementia of the Alzheimer's Type

ERIC Educational Resources Information Center

Muller, Nicole; Guendouzi, Jacqueline A.

2005-01-01

After a brief introduction to Dementia of the Alzheimer's Type (DAT), its behavioral diagnostic symptom complex and a summary of communicative implications, we present data from two conversations involving participants with and without DAT. We discuss the concept of "order" in conversation, and the central importance of interactional monitoring.…

S182 and STM2 gene missense mutations in sporadic alzheimer disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Higuchi, Susumu; Matsushita, Sachio; Hasegawa, Yoshio

1996-07-26

The linkage of genes S182 and STM2 to early-onset or late-onset sporadic Alzheimer disease (AD) was not found in a group of 97 clinically-diagnosed AD patients and 46 autopsy-confirmed AD cases, using PCR-RFLP methods. 7 refs.

Risk factors for age at onset of dementia due to Alzheimer's disease in a sample of patients with low mean schooling from São Paulo, Brazil.

PubMed

de Oliveira, Fabricio Ferreira; Bertolucci, Paulo Henrique Ferreira; Chen, Elizabeth Suchi; Smith, Marilia Cardoso

2014-10-01

In view of the mild effects of pharmacological treatment for dementia due to Alzheimer's disease (AD), the search for modifiable risk factors is an important challenge. Although risk factors for AD are widely recognized, elements that influence the time of onset of the dementia syndrome have not been comprehensively reported. We aimed to investigate which risk factors might be associated with the age at onset of AD in a sample of patients with low mean schooling from São Paulo, Brazil. We included 210 consecutive patients with late-onset AD to investigate whether education, gender, nationality, urban living and sanitation, occupation, cognitive and physical inactivity, head trauma, depression, systemic infections, surgical interventions, cerebrovascular risk factors, family history of neurodegenerative diseases or cardiovascular diseases and apolipoprotein E gene (APOE) haplotypes might be related to the age at AD onset. Each copy of APOE-ε4 led to onset of AD almost 2 years earlier, while depression, smoking, higher body mass index and family history of cardiovascular diseases were also highly significant. Protective factors included non-Brazilian nationality, use of a pacemaker and waist circumference. Cerebrovascular risk factors had a mild combined effect for earlier onset of AD. APOE haplotypes, depression, nationality and cerebrovascular risk factors were the most important elements to influence the age at AD onset in this sample, whereas gender, education, occupation and physical activities had no isolated effects over the age at onset of this dementia syndrome. Copyright © 2014 John Wiley & Sons, Ltd.

Absence of nocturnal fall in blood pressure in elderly persons with Alzheimer-type dementia.

PubMed

Otsuka, A; Mikami, H; Katahira, K; Nakamoto, Y; Minamitani, K; Imaoka, M; Nishide, M; Ogihara, T

1990-09-01

Circadian changes of the blood pressure and heart rate in elderly normotensive bedridden patients with severe dementia of the Alzheimer type (group D) were compared with those in elderly normotensive bedridden patients without dementia (group R), normotensive subjects with normal daily activity (group N), and hypertensive patients with normal daily activity (group H). In groups R, N, and H, the blood pressure increased in the afternoon and decreased at midnight; in group D, however, although it increased in the afternoon, it did not decrease at night. The circadian changes of the heart rate were similar in all four groups, showing maxima in the afternoon and minima at midnight. Thus, a specific alteration was found in the circadian rhythm of the blood pressure in patients with Alzheimer-type dementia.

When aging-onset diabetes is coming across with Alzheimer disease: comparable pathogenesis and therapy.

PubMed

Tang, Jun; Pei, Yijin; Zhou, Guangji

2013-08-01

Diabetes mellitus is a metabolic disorder that is characterized by high blood glucose because of the insulin-resistance and insulin-deficiency in Type 2, while the insulin deficiency due to destruction of islet cells in the pancreas in Type 1. The development of Type 2 diabetes is caused by a combination of lifestyle and genetic factors. Aging patients with diabetes are at increased risk of developing cognitive and memory dysfunctions, which is one of the significant symptoms of Alzheimer disease (AD). Also, over 2/3 of AD patients were clinically indentified with impairment of glucose. Cognitive dysfunction would be associated with poor self-care ability in diabetes patients. This review will briefly summarize the current knowledge of the pathogenesis of these two diseases and highlight similarities in their pathophysiologies. Furthermore, we will shortly discuss recent progress in the insulin-targeted strategy, aiming to explore the inner linkage between these two diseases in aging populations. Copyright © 2013 Elsevier Inc. All rights reserved.

Racial and ethnic differences among children with new-onset autoimmune type 1 diabetes

USDA-ARS?s Scientific Manuscript database

To compare demographic and clinical characteristics among children from ethnic minorities and non-Hispanic white children with new-onset autoimmune Type 1 diabetes. We analyzed a single-center series of 712 children with new-onset autoimmune Type 1 diabetes between January 2008 and March 2011. The m...

Anosognosia and Its Relation to Psychiatric Symptoms in Early-Onset Alzheimer Disease.

PubMed

Yoon, Bora; Shim, Yong S; Hong, Yun Jeong; Choi, Seong Hye; Park, Hee Kyung; Park, Sun Ah; Jeong, Jee Hyang; Yoon, Soo Jin; Yang, Dong-Won

2017-05-01

We investigated differences in the prevalence of anosognosia and neuropsychiatric symptoms (NPSs) characteristics according to disease severity in patients with early-onset Alzheimer disease (EOAD). We recruited 616 patients with EOAD. We subdivided participants into 2 groups based on the presence or absence of anosognosia and then again by Clinical Dementia Rating (CDR) scale. We compared the differences in the Neuropsychiatric Inventory (NPI) scores according to anosognosia and disease severity. The percentage of patients with anosognosia in each CDR group steadily increased as the CDR rating increased (CDR 0.5 8.6% vs CDR 1 13.6% vs CDR 2 26.2%). The NPI total score was significantly higher in patients with anosognosia in the CDR 0.5 and 1 groups; by contrast, it had no association in the CDR 2 group. Frontal lobe functions were associated with anosognosia only in the CDR 0.5 and 1 groups. After stratification by CDR, in the CDR 0.5 group, the prevalence of agitation ( P = .040) and appetite ( P = .013) was significantly higher in patients with anosognosia. In the CDR 1 group, patients with anosognosia had a significantly higher prevalence of delusions ( P = .032), hallucinations ( P = .048), and sleep disturbances ( P = .047). In the CDR 2 group, we found no statistical difference in the frequency of symptoms between patients with and without anosognosia. These results confirm that the prevalence of anosognosia as well as the individual NPS and cognitive functions associated with it differ according to EOAD severity.

The onset time of amiodarone-induced thyrotoxicosis (AIT) depends on AIT type.

PubMed

Tomisti, Luca; Rossi, Giuseppe; Bartalena, Luigi; Martino, Enio; Bogazzi, Fausto

2014-09-01

Considering the different pathogenic mechanisms of the two main forms of amiodarone-induced thyrotoxicosis (AIT), we ascertained whether this results in a different onset time as well. We retrospectively analyzed the clinical records of 200 consecutive AIT patients (157 men and 43 women; mean age 62.2±12.6 years) referred to our Department from 1987 to 2012. The onset time of AIT was defined as the time elapsed from the beginning of amiodarone therapy and the first diagnosis of thyrotoxicosis, expressed in months. Factors associated with the onset time of AIT were evaluated by univariate and multivariate analyses. The median onset time of thyrotoxicosis was 3.5 months (95% CI 2-6 months) in patients with type 1 AIT (AIT1) and 30 months (95% CI 27-32 months, P<0.001) in those with type 2 AIT (AIT2). Of the total number of patients, 5% with AIT1 and 23% with AIT2 (P=0.007) developed thyrotoxicosis after amiodarone withdrawal. Factors affecting the onset time of thyrotoxicosis were the type of AIT and thyroid volume (TV). The different pathogenic mechanisms of the two forms of AIT account for different onset times of thyrotoxicosis in the two groups. Patients with preexisting thyroid abnormalities (candidate to develop AIT1) may require a stricter follow-up during amiodarone therapy than those usually recommended. In AIT1, the onset of thyrotoxicosis after amiodarone withdrawal is rare, while AIT2 patients may require periodic tests for thyroid function longer after withdrawing amiodarone. © 2014 European Society of Endocrinology.

Role of σ1 Receptors in Learning and Memory and Alzheimer's Disease-Type Dementia.

PubMed

Maurice, Tangui; Goguadze, Nino

2017-01-01

The present chapter will review the role of σ 1 receptor in learning and memory and neuroprotection , against Alzheimer's type dementia. σ 1 Receptor agonists have been tested in a variety of pharmacological and pathological models of learning impairments in rodents these last past 20 years. Their anti-amnesic effects have been explained by the wide-range modulatory role of σ 1 receptors on Ca 2+ mobilizations, neurotransmitter responses, and particularly glutamate and acetylcholine systems, and neurotrophic factors. Recent observations from genetic and pharmacological studies have shown that σ 1 receptor can also be targeted in neurodegenerative diseases, and particularly Alzheimer's disease . Several compounds, acting partly through the σ 1 receptor, have showed effective neuroprotection in transgenic mouse models of Alzheimer's disease . We will review the data and discuss the possible mechanisms of action, particularly focusing on oxidative stress and mitochondrial integrity, trophic factors and a novel hypothesis suggesting a functional interaction between the σ 1 receptor and α 7 nicotinic acetylcholine receptor. Finally, we will discuss the pharmacological peculiarities of non-selective σ 1 receptor ligands, now developed as neuroprotectants in Alzheimer's disease , and positive modulators, recently described and that showed efficacy against learning and memory deficits.

How Should Clinicians Counsel a Woman with a Strong Family History of Early-Onset Alzheimer's Disease about Her Pregnancy?

PubMed

Mapes, Marianna V; O'Brien, Barbara M; King, Louise P

2017-07-01

Counseling patients regarding the benefits, harms, and dilemmas of genetic testing is one of the greatest ethical challenges facing reproductive medicine today. With or without test results, clinicians grapple with how to communicate potential genetic risks as patients weigh their reproductive options. Here, we consider a case of a woman with a strong family history of early-onset Alzheimer's disease (EOAD). She is early in her pregnancy and unsure about learning her own genetic status. We address the ethical ramifications of each of her options, which include genetic testing, genetic counseling, and termination versus continuation of the pregnancy. Our analysis foregrounds clinicians' role in helping to ensure autonomous decision making as the patient reflects on these clinical options in light of her goals and values. © 2017 American Medical Association. All Rights Reserved.

Complete genomic screen in late-onset familial Alzheimer disease. Evidence for a new locus on chromosome 12.

PubMed

Pericak-Vance, M A; Bass, M P; Yamaoka, L H; Gaskell, P C; Scott, W K; Terwedow, H A; Menold, M M; Conneally, P M; Small, G W; Vance, J M; Saunders, A M; Roses, A D; Haines, J L

1997-10-15

Four genetic loci have been identified as contributing to Alzheimer disease (AD), including the amyloid precursor protein gene, the presenilin 1 gene, the presenilin 2 gene, and the apolipoprotein E gene, but do not account for all the genetic risk for AD. To identify additional genetic risk factors for late-onset AD. A complete genomic screen was performed (N=280 markers). Critical values for chromosomal regional follow-up were a P value of .05 or less for affected relative pair analysis or sibpair analysis, a parametric lod score of 1.0 or greater, or both. Regional follow-up included analysis of additional markers and a second data set. Clinic populations in the continental United States. From a series of multiplex families affected with late-onset (> or =60 years) AD ascertained during the last 14 years (National Insititute of Neurological Disorders and Stroke-Alzheimer's Disease and Related Disorders Association diagnostic criteria) and for which DNA has been obtained, a subset of 16 families (135 total family members, 52 of whom were patients with AD) was used for the genomic screen. A second subset of 38 families (216 total family members, 89 of whom were patients with AD) was used for the follow-up analysis. Linkage analysis results generated using both genetic model-dependent (lod score) and model-independent methods. Fifteen chromosomal regions warranted initial follow-up. Follow-up analyses revealed 4 regions of continued interest on chromosomes 4, 6, 12, and 20, with the strongest results observed forchromosome 12. Peak 2-point affecteds-only lod scores (n=54) were 1.3, 1.6, 2.7, and 2.2 and affected relative pairs P values (n=54) were .04, .03, .14, and .04 for D12S373, D12S1057, D12S1042, and D12S390, respectively. Sibpair analysis (n=54) resulted in maximum lod scores (MLSs) of 1.5, 2.6, 3.2, and 2.3 for these markers, with a peak multipoint MLS of 3.5. A priori stratification by APOE genotype identified 27 families that had at least 1 member with AD

Adult-Onset Type 1 Diabetes: A Qualitative Study of Decision-Making Needs.

PubMed

Jull, Janet; Witteman, Holly O; Ferne, Judi; Yoganathan, Manosila; Stacey, Dawn

2016-04-01

Type 1 diabetes is an autoimmune disease resulting from insulin deficiency and must be carefully managed to prevent serious health complications. Diabetes education and management strategies usually focus on meeting the decision-making needs of children and their families, but little is known about the decisional needs of people with adult-onset type 1 diabetes. The aim of this study was to explore the diabetes-related decision-making needs of people diagnosed with adult-onset type 1 diabetes. An interpretive descriptive qualitative study was conducted. Participants who self-identified as having adult-onset type 1 diabetes were interviewed using a semistructured interview guide. Transcripts were coded to identify needs, supports and barriers using thematic analysis. Participating in the study were 8 adults (2 men, 6 women), ages 33 to 57, with type 1 diabetes for durations of 1 to 20 or more years. Their decision-making needs are summarized in 6 broad themes: 1) people diagnosed with type 1 diabetes are launched into a process of decision-making; 2) being diagnosed with type 1 diabetes means you will always have to make decisions; 3) knowledge is crucial; 4) personal preferences matter; 5) support is critical for decisions about self-care in type 1 diabetes; 6) living with type 1 diabetes means making very individualized decisions about daily life. The findings describe the sudden and ubiquitous nature of type 1 diabetes decision-making and the need to tailor approaches for making care decisions in type 1 diabetes. People diagnosed with adult-onset type 1 diabetes require access to reliable information, support and opportunities for participation in decision-making. Copyright © 2016 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

Presymptomatic atrophy in autosomal dominant Alzheimer's disease: A serial magnetic resonance imaging study.

PubMed

Kinnunen, Kirsi M; Cash, David M; Poole, Teresa; Frost, Chris; Benzinger, Tammie L S; Ahsan, R Laila; Leung, Kelvin K; Cardoso, M Jorge; Modat, Marc; Malone, Ian B; Morris, John C; Bateman, Randall J; Marcus, Daniel S; Goate, Alison; Salloway, Stephen P; Correia, Stephen; Sperling, Reisa A; Chhatwal, Jasmeer P; Mayeux, Richard P; Brickman, Adam M; Martins, Ralph N; Farlow, Martin R; Ghetti, Bernardino; Saykin, Andrew J; Jack, Clifford R; Schofield, Peter R; McDade, Eric; Weiner, Michael W; Ringman, John M; Thompson, Paul M; Masters, Colin L; Rowe, Christopher C; Rossor, Martin N; Ourselin, Sebastien; Fox, Nick C

2018-01-01

Identifying at what point atrophy rates first change in Alzheimer's disease is important for informing design of presymptomatic trials. Serial T1-weighted magnetic resonance imaging scans of 94 participants (28 noncarriers, 66 carriers) from the Dominantly Inherited Alzheimer Network were used to measure brain, ventricular, and hippocampal atrophy rates. For each structure, nonlinear mixed-effects models estimated the change-points when atrophy rates deviate from normal and the rates of change before and after this point. Atrophy increased after the change-point, which occurred 1-1.5 years (assuming a single step change in atrophy rate) or 3-8 years (assuming gradual acceleration of atrophy) before expected symptom onset. At expected symptom onset, estimated atrophy rates were at least 3.6 times than those before the change-point. Atrophy rates are pathologically increased up to seven years before "expected onset". During this period, atrophy rates may be useful for inclusion and tracking of disease progression. Copyright © 2017 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

TREM2 Variants in Alzheimer's Disease

PubMed Central

Guerreiro, Rita; Wojtas, Aleksandra; Bras, Jose; Carrasquillo, Minerva; Rogaeva, Ekaterina; Majounie, Elisa; Cruchaga, Carlos; Sassi, Celeste; Kauwe, John S.K.; Younkin, Steven; Hazrati, Lilinaz; Collinge, John; Pocock, Jennifer; Lashley, Tammaryn; Williams, Julie; Lambert, Jean-Charles; Amouyel, Philippe; Goate, Alison; Rademakers, Rosa; Morgan, Kevin; Powell, John; St. George-Hyslop, Peter; Singleton, Andrew; Hardy, John

2013-01-01

BACKGROUND Homozygous loss-of-function mutations in TREM2, encoding the triggering receptor expressed on myeloid cells 2 protein, have previously been associated with an autosomal recessive form of early-onset dementia. METHODS We used genome, exome, and Sanger sequencing to analyze the genetic variability in TREM2 in a series of 1092 patients with Alzheimer's disease and 1107 controls (the discovery set). We then performed a meta-analysis on imputed data for the TREM2 variant rs75932628 (predicted to cause a R47H substitution) from three genomewide association studies of Alzheimer's disease and tested for the association of the variant with disease. We genotyped the R47H variant in an additional 1887 cases and 4061 controls. We then assayed the expression of TREM2 across different regions of the human brain and identified genes that are differentially expressed in a mouse model of Alzheimer's disease and in control mice. RESULTS We found significantly more variants in exon 2 of TREM2 in patients with Alzheimer's disease than in controls in the discovery set (P = 0.02). There were 22 variant alleles in 1092 patients with Alzheimer's disease and 5 variant alleles in 1107 controls (P<0.001). The most commonly associated variant, rs75932628 (encoding R47H), showed highly significant association with Alzheimer's disease (P<0.001). Meta-analysis of rs75932628 genotypes imputed from genomewide association studies confirmed this association (P = 0.002), as did direct genotyping of an additional series of 1887 patients with Alzheimer's disease and 4061 controls (P<0.001). Trem2 expression differed between control mice and a mouse model of Alzheimer's disease. CONCLUSIONS Heterozygous rare variants in TREM2 are associated with a significant increase in the risk of Alzheimer's disease. (Funded by Alzheimer's Research UK and others.) PMID:23150934

Impact of Alzheimer's-Type Dementia and Information Source on the Assessment of Depression.

ERIC Educational Resources Information Center

Gilley, David W.; And Others

1995-01-01

The level of agreement between the patient and a collateral source with regard to depressive symptomatology was compared for 185 patients with Alzheimer's-type dementia (AD), 57 patients with Parkinson's disease, and 54 nondemented geriatric referrals. Findings highlight the potential insensitivity of patient report in AD. (SLD)

Systems biology approach to late-onset Alzheimer's disease genome-wide association study identifies novel candidate genes validated using brain expression data and Caenorhabditis elegans experiments.

PubMed

Mukherjee, Shubhabrata; Russell, Joshua C; Carr, Daniel T; Burgess, Jeremy D; Allen, Mariet; Serie, Daniel J; Boehme, Kevin L; Kauwe, John S K; Naj, Adam C; Fardo, David W; Dickson, Dennis W; Montine, Thomas J; Ertekin-Taner, Nilufer; Kaeberlein, Matt R; Crane, Paul K

2017-10-01

We sought to determine whether a systems biology approach may identify novel late-onset Alzheimer's disease (LOAD) loci. We performed gene-wide association analyses and integrated results with human protein-protein interaction data using network analyses. We performed functional validation on novel genes using a transgenic Caenorhabditis elegans Aβ proteotoxicity model and evaluated novel genes using brain expression data from people with LOAD and other neurodegenerative conditions. We identified 13 novel candidate LOAD genes outside chromosome 19. Of those, RNA interference knockdowns of the C. elegans orthologs of UBC, NDUFS3, EGR1, and ATP5H were associated with Aβ toxicity, and NDUFS3, SLC25A11, ATP5H, and APP were differentially expressed in the temporal cortex. Network analyses identified novel LOAD candidate genes. We demonstrated a functional role for four of these in a C. elegans model and found enrichment of differentially expressed genes in the temporal cortex. Copyright © 2017 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Age at Onset of Type 1 Diabetes in Parents and Recurrence Risk in Offspring

PubMed Central

Harjutsalo, Valma; Lammi, Niina; Karvonen, Marjatta; Groop, Per-Henrik

2010-01-01

OBJECTIVE Our aim was to study the recurrence risk of type 1 diabetes in the offspring of parents with adult-onset (15–39 years) type 1 diabetes and to evaluate the transmission of diabetes within a continuum of parental age at onset of diabetes from childhood to adulthood. RESEARCH DESIGN AND METHODS Diabetes status of all offspring (n = 9,636) in two Finnish cohorts of parents with type 1 diabetes was defined until the end of year 2007. Cumulative incidences of type 1 diabetes among the offspring were estimated, and several factors contributing to the risk were assessed. RESULTS During 137,455 person-years, a total of 413 offspring were diagnosed with type 1 diabetes. The cumulative incidence by 20 years was 4.0% (95% CI 3.1–4.8) for the offspring of parents with adult-onset diabetes. The risk was equal according to the sex of the parents. The cumulative incidence decreased in parallel with the increase in age at onset of diabetes in the fathers. In the offspring of diabetic mothers, the risk was equal regardless of the age at onset of diabetes. However, the reduced risk in the maternal offspring was most pronounced in the daughters of the mothers with a diagnosis age <10 years. CONCLUSIONS Type 1 diabetes transmission ratio distortion is strongly related to the sex and age at onset of diabetes in the diabetic parents. PMID:19833881

Differentiation of neuropsychological features between posterior cortical atrophy and early onset Alzheimer's disease.

PubMed

Li, Jieying; Wu, Liyong; Tang, Yi; Zhou, Aihong; Wang, Fen; Xing, Yi; Jia, Jianping

2018-05-10

Posterior cortical atrophy (PCA) is a group of clinical syndromes characterized by visuospatial and visuoperceptual impairment, with memory relatively preserved. Although PCA is pathologically almost identical to Alzheimer's disease (AD), they have different cognitive features. Those differences have only rarely been reported in any Chinese population. The purpose of the study is to establish neuropsychological tests that distinguish the clinical features of PCA from early onset AD (EOAD). Twenty-one PCA patients, 20 EOAD patients, and 20 healthy controls participated in this study. Patients had disease duration of ≤4 years. All participants completed a series of neuropsychological tests to evaluate their visuospatial, visuoperceptual, visuo-constructive, language, executive function, memory, calculation, writing, and reading abilities. The cognitive features of PCA and EOAD were compared. All the neuropsychological test scores showed that both the PCA and EOAD patients were significantly more impaired than people in the control group. However, PCA patients were significantly more impaired than EOAD patients in visuospatial, visuoperceptual, and visuo-constructive function, as well as in handwriting, and reading Chinese characters. The profile of neuropsychological test results highlights cognitive features that differ between PCA and EOAD. One surprising result is that the two syndromes could be distinguished by patients' ability to read and write Chinese characters. Tests based on these characteristics could therefore form a brief PCA neuropsychological examination that would improve the diagnosis of PCA.

Late-onset Bartter syndrome type II.

PubMed

Gollasch, Benjamin; Anistan, Yoland-Marie; Canaan-Kühl, Sima; Gollasch, Maik

2017-10-01

Mutations in the ROMK1 potassium channel gene ( KCNJ1 ) cause antenatal/neonatal Bartter syndrome type II (aBS II), a renal disorder that begins in utero , accounting for the polyhydramnios and premature delivery that is typical in affected infants, who develop massive renal salt wasting, hypokalaemic metabolic alkalosis, secondary hyperreninaemic hyperaldosteronism, hypercalciuria and nephrocalcinosis. This BS type is believed to represent a disorder of the infancy, but not in adulthood. We herein describe a female patient with a remarkably late-onset and mild clinical manifestation of BS II with compound heterozygous KCNJ1 missense mutations, consisting of a novel c.197T > A (p.I66N) and a previously reported c.875G > A (p.R292Q) KCNJ1 mutation. We implemented and evaluated the performance of two different bioinformatics-based approaches of targeted massively parallel sequencing [next generation sequencing (NGS)] in defining the molecular diagnosis. Our results demonstrate that aBS II may be suspected in patients with a late-onset phenotype. Our experimental approach of NGS-based mutation screening combined with Sanger sequencing proved to be a reliable molecular approach for defining the clinical diagnosis in our patient, and results in important differential diagnostic and therapeutic implications for patients with BS. Our results could have a significant impact on the diagnosis and methodological approaches of genetic testing in other patients with clinical unclassified phenotypes of nephrocalcinosis and congenital renal electrolyte abnormalities.

Screening of Early and Late Onset Alzheimer's Disease Genetic Risk Factors in a Cohort of Dementia Patients from Liguria, Italy.

PubMed

Ferrari, Raffaele; Ferrara, Michela; Alinani, Anwar; Sutton, Roger Brian; Famà, Francesco; Picco, Agnese; Rodriguez, Guido; Nobili, Flavio; Momeni, Parastoo

2015-01-01

Cohorts from a defined geographical area enable ad hoc genotype-phenotype correlation studies providing novel and unique insight into disease. We analysed genetic risk factors associated with early and late onset Alzheimer's disease (EOAD and LOAD) in a population from Liguria (northern Italy), as part of an ongoing longitudinal study. We screened 37 AD, 8 mild cognitive impairment (MCI), 3 AD and CVD (cerebrovascular disease), 3 MCI and CVD, 8 frontotemporal dementia (FTD) and 2 progressive supranuclear palsy (PSP) patients, and 28 normal controls (NCs).We sequenced PSEN1, PSEN2 and APP (EOAD risk factors), as well as MAPT, GRN and TARDBP for all cases and NCs, and analysed the APOE, CLU, CR1 and PICALM genotypes as well as the MAPT and ACE haplotypes (LOAD risk factors) for the AD (n = 37) and AD + MCI (n = 45) cases and NCs (n = 28).We identified variants in PSEN1, PSEN2 and TARDBP across a range of phenotypes (AD, AD and CVD, FTD and PSP), suggesting that screening of all known candidate genes of Alzheimer's and non-Alzheimer's forms of dementias in all dementia cases might be warranted. The analysis of the LOAD risk factors revealed no association with AD or AD + MCI status after Bonferroni correction. Lack of association with APOE is supported by previous studies in the Italian population. Our data also evidenced: 1) a potentially protective haplotype at the PSEN2 locus; 2) a nominal association with the GWAS-risk allele A for rs3818361 in CR1 and; 3) a threefold prevalence of AD in the female population compared to men.Our results will need to be further assessed and confirmed in larger cohorts from this area. 

The Association Between Clusterin and APOE Polymorphisms and Late-Onset Alzheimer Disease in a Turkish Cohort.

PubMed

Alaylıoğlu, Merve; Gezen-Ak, Duygu; Dursun, Erdinç; Bilgiç, Başar; Hanağası, Haşmet; Ertan, Turan; Gürvit, Hakan; Emre, Murat; Eker, Engin; Uysal, Ömer; Yılmazer, Selma

2016-07-01

Previous studies have demonstrated that clusterin (CLU), which is also known as apolipoprotein J, is involved in the pathogenesis of Alzheimer disease (AD). In this study, we investigated the association between rs2279590, rs11136000, and rs9331888 single-nucleotide polymorphisms (SNPs) in CLU and apolipoprotein E (APOE) genotypes in a cohort of Turkish patients with late-onset AD (LOAD). There were 183 patients with LOAD and 154 healthy controls included in the study. The CLU and APOE polymorphisms were genotyped using the LightSNiP assay. The "GG" genotype of rs9331888 was significantly more frequent in patients with LOAD. The "CC" genotype of the SNP was significantly more frequent in controls. The rs9331888 "GG" genotype in patients and the "CC" genotype in controls were significantly higher in non-∊4 allele carriers of APOE The haplotype analysis showed the CLU "GCG" haplotype was a risk haplotype. Our findings indicate the rs9331888 SNP of CLU is associated with LOAD independent of APOE. © The Author(s) 2016.

Polymorphisms in HSD17B1: Early Onset and Increased Risk of Alzheimer's Disease in Women with Down Syndrome.

PubMed

Lee, Joseph H; Gurney, Susan; Pang, Deborah; Temkin, Alexis; Park, Naeun; Janicki, Sarah C; Zigman, Warren B; Silverman, Wayne; Tycko, Benjamin; Schupf, Nicole

2012-01-01

Background/Aims. Genetic variants that affect estrogen activity may influence the risk of Alzheimer's disease (AD). In women with Down syndrome, we examined the relation of polymorphisms in hydroxysteroid-17beta-dehydrogenase (HSD17B1) to age at onset and risk of AD. HSD17B1 encodes the enzyme 17β-hydroxysteroid dehydrogenase (HSD1), which catalyzes the conversion of estrone to estradiol. Methods. Two hundred and thirty-eight women with DS, nondemented at baseline, 31-78 years of age, were followed at 14-18-month intervals for 4.5 years. Women were genotyped for 5 haplotype-tagging single-nucleotide polymorphisms (SNPs) in the HSD17B1 gene region, and their association with incident AD was examined. Results. Age at onset was earlier, and risk of AD was elevated from two- to threefold among women homozygous for the minor allele at 3 SNPs in intron 4 (rs676387), exon 6 (rs605059), and exon 4 in COASY (rs598126). Carriers of the haplotype TCC, based on the risk alleles for these three SNPs, had an almost twofold increased risk of developing AD (hazard ratio = 1.8, 95% CI, 1.1-3.1). Conclusion. These findings support experimental and clinical studies of the neuroprotective role of estrogen.

Two types of expansion onsets in the Earth's two hemispheres

NASA Astrophysics Data System (ADS)

Foerster, M.; Mishin, V.; Mishin, V. M.; Kurikalova, M.; Karavaev, Y.; Lunyushkin, S.

2016-12-01

On the maps of distribution of field - aligned currents (FAC) of 15 investigated substorms we have found two main types of M-I feedback instability: 1) "summer" (type 1), and 2) "winter" (type 2). In equinox both types were observed, different in the two hemispheres. Each type of instability creates two simultaneous local expansion onsets, EOs: Type 1 - non-linear amplification of the downward FAC in one hemisphere and Type 2 - non-linear amplification of the upward FAC in the other hemisphere.

The Proteasome and Oxidative Stress in Alzheimer's Disease.

PubMed

Bonet-Costa, Vicent; Pomatto, Laura Corrales-Diaz; Davies, Kelvin J A

2016-12-01

Alzheimer's disease is a neurodegenerative disorder that is projected to exceed more than 100 million cases worldwide by 2050. Aging is considered the primary risk factor for some 90% of Alzheimer's cases but a significant 10% of patients suffer from aggressive, early-onset forms of the disease. There is currently no effective Alzheimer's treatment and this, coupled with a growing aging population, highlights the necessity to understand the mechanism(s) of disease initiation and propagation. A major hallmark of Alzheimer's disease pathology is the accumulation of amyloid-β (Aβ) aggregates (an early marker of Alzheimer's disease), and neurofibrillary tangles, comprising the hyper-phosphorylated microtubule-associated protein Tau. Recent Advances: Protein oxidation is frequently invoked as a potential factor in the progression of Alzheimer's disease; however, whether it is a cause or a consequence of the pathology is still being debated. The Proteasome complex is a major regulator of intracellular protein quality control and an essential proteolytic enzyme for the processing of both Aβ and Tau. Recent studies have indicated that both protein oxidation and excessive phosphorylation may limit Proteasomal processing of Aβ and Tau in Alzheimer's disease. Thus, the Proteasome may be a key factor in understanding the development of Alzheimer's disease pathology; however, its significance is still very much under investigation. Discovering how the proteasome is affected, regulated, or dysregulated in Alzheimer's disease could be a valuable tool in the efforts to understand and, ultimately, eradicate the disease. Antioxid. Redox Signal. 25, 886-901.

The Alzheimer's prevention initiative composite cognitive test score: sample size estimates for the evaluation of preclinical Alzheimer's disease treatments in presenilin 1 E280A mutation carriers.

PubMed

Ayutyanont, Napatkamon; Langbaum, Jessica B S; Hendrix, Suzanne B; Chen, Kewei; Fleisher, Adam S; Friesenhahn, Michel; Ward, Michael; Aguirre, Camilo; Acosta-Baena, Natalia; Madrigal, Lucìa; Muñoz, Claudia; Tirado, Victoria; Moreno, Sonia; Tariot, Pierre N; Lopera, Francisco; Reiman, Eric M

2014-06-01

To identify a cognitive composite that is sensitive to tracking preclinical Alzheimer's disease decline to be used as a primary end point in treatment trials. We capitalized on longitudinal data collected from 1995 to 2010 from cognitively unimpaired presenilin 1 (PSEN1) E280A mutation carriers from the world's largest known early-onset autosomal dominant Alzheimer's disease kindred to identify a composite cognitive test with the greatest statistical power to track preclinical Alzheimer's disease decline and estimate the number of carriers age 30 years and older needed to detect a treatment effect in the Alzheimer's Prevention Initiative's (API) preclinical Alzheimer's disease treatment trial. The mean-to-standard-deviation ratios (MSDRs) of change over time were calculated in a search for the optimal combination of 1 to 7 cognitive tests/subtests drawn from the neuropsychological test battery in cognitively unimpaired mutation carriers during a 2- and 5-year follow-up period (n = 78 and 57), using data from noncarriers (n = 31 and 56) during the same time period to correct for aging and practice effects. Combinations that performed well were then evaluated for robustness across follow-up years, occurrence of selected items within top-performing combinations, and representation of relevant cognitive domains. The optimal test combination included Consortium to Establish a Registry for Alzheimer's Disease (CERAD) Word List Recall, CERAD Boston Naming Test (high frequency items), Mini-Mental State Examination (MMSE) Orientation to Time, CERAD Constructional Praxis, and Raven's Progressive Matrices (Set A), with an MSDR of 1.62. This composite is more sensitive than using either the CERAD Word List Recall (MSDR = 0.38) or the entire CERAD-Col battery (MSDR = 0.76). A sample size of 75 cognitively normal PSEN1 E280A mutation carriers aged 30 years and older per treatment arm allows for a detectable treatment effect of 29% in a 60-month trial (80% power, P = .05). We

SORL1 variants across Alzheimer's disease European American cohorts.

PubMed

Fernández, Maria Victoria; Black, Kathleen; Carrell, David; Saef, Ben; Budde, John; Deming, Yuetiva; Howells, Bill; Del-Aguila, Jorge L; Ma, Shengmei; Bi, Catherine; Norton, Joanne; Chasse, Rachel; Morris, John; Goate, Alison; Cruchaga, Carlos

2016-12-01

The accumulation of the toxic Aβ peptide in Alzheimer's disease (AD) largely relies upon an efficient recycling of amyloid precursor protein (APP). Recent genetic association studies have described rare variants in SORL1 with putative pathogenic consequences in the recycling of APP. In this work, we examine the presence of rare coding variants in SORL1 in three different European American cohorts: early-onset, late-onset AD (LOAD) and familial LOAD.

Delaying Onset of Dementia: Are Two Languages Enough?

PubMed Central

Freedman, Morris; Alladi, Suvarna; Chertkow, Howard; Bialystok, Ellen; Craik, Fergus I. M.; Phillips, Natalie A.; Duggirala, Vasanta; Raju, Surampudi Bapi; Bak, Thomas H.

2014-01-01

There is an emerging literature suggesting that speaking two or more languages may significantly delay the onset of dementia. Although the mechanisms are unknown, it has been suggested that these may involve cognitive reserve, a concept that has been associated with factors such as higher levels of education, occupational status, social networks, and physical exercise. In the case of bilingualism, cognitive reserve may involve reorganization and strengthening of neural networks that enhance executive control. We review evidence for protective effects of bilingualism from a multicultural perspective involving studies in Toronto and Montreal, Canada, and Hyderabad, India. Reports from Toronto and Hyderabad showed a significant effect of speaking two or more languages in delaying onset of Alzheimer's disease by up to 5 years, whereas the Montreal study showed a significant protective effect of speaking at least four languages and a protective effect of speaking at least two languages in immigrants. Although there were differences in results across studies, a common theme was the significant effect of language use history as one of the factors in determining the onset of Alzheimer's disease. Moreover, the Hyderabad study extended the findings to frontotemporal dementia and vascular dementia. PMID:24959001

Delaying onset of dementia: are two languages enough?

PubMed

Freedman, Morris; Alladi, Suvarna; Chertkow, Howard; Bialystok, Ellen; Craik, Fergus I M; Phillips, Natalie A; Duggirala, Vasanta; Raju, Surampudi Bapi; Bak, Thomas H

2014-01-01

There is an emerging literature suggesting that speaking two or more languages may significantly delay the onset of dementia. Although the mechanisms are unknown, it has been suggested that these may involve cognitive reserve, a concept that has been associated with factors such as higher levels of education, occupational status, social networks, and physical exercise. In the case of bilingualism, cognitive reserve may involve reorganization and strengthening of neural networks that enhance executive control. We review evidence for protective effects of bilingualism from a multicultural perspective involving studies in Toronto and Montreal, Canada, and Hyderabad, India. Reports from Toronto and Hyderabad showed a significant effect of speaking two or more languages in delaying onset of Alzheimer's disease by up to 5 years, whereas the Montreal study showed a significant protective effect of speaking at least four languages and a protective effect of speaking at least two languages in immigrants. Although there were differences in results across studies, a common theme was the significant effect of language use history as one of the factors in determining the onset of Alzheimer's disease. Moreover, the Hyderabad study extended the findings to frontotemporal dementia and vascular dementia.

Do adolescent drug users fare the worst? Onset type, juvenile delinquency, and criminal careers.

PubMed

DeLisi, Matt; Angton, Alexia; Behnken, Monic P; Kusow, Abdi M

2015-02-01

Although substance abuse often accompanies delinquency and other forms of antisocial behavior, there is less scholarly agreement about the timing of substance use vis-à-vis an individual's antisocial trajectory. Similarly, although there is extraordinary evidence that onset is inversely related to the severity of the criminal career, there is surprisingly little research on the offense type of onset or the type of antisocial behavior that was displayed when an individual initiated his or her offending career. Drawing on data from a sample of serious adult criminal offenders (N = 500), the current study examined 12 forms of juvenile delinquency (murder, rape, robbery, aggravated assault, burglary, larceny, auto theft, arson, weapons, sexual offense, drug sales, and drug use) in addition to age at arrest onset, age, sex, race to explore their association with chronicity (total arrests), extreme chronicity (1 SD above the mean which was equivalent to 90 career arrests), and lambda (offending per year). The only onset offense type that was significantly associated with all criminal career outcomes was juvenile drug use. Additional research on the offense type of delinquent onset is needed to understand launching points of serious antisocial careers. © The Author(s) 2013.

A genetic cause of Alzheimer disease: mechanistic insights from Down syndrome.

PubMed

Wiseman, Frances K; Al-Janabi, Tamara; Hardy, John; Karmiloff-Smith, Annette; Nizetic, Dean; Tybulewicz, Victor L J; Fisher, Elizabeth M C; Strydom, André

2015-09-01

Down syndrome, which arises in individuals carrying an extra copy of chromosome 21, is associated with a greatly increased risk of early-onset Alzheimer disease. It is thought that this risk is conferred by the presence of three copies of the gene encoding amyloid precursor protein (APP)--an Alzheimer disease risk factor--although the possession of extra copies of other chromosome 21 genes may also play a part. Further study of the mechanisms underlying the development of Alzheimer disease in people with Down syndrome could provide insights into the mechanisms that cause dementia in the general population.

A genetic cause of Alzheimer disease: mechanistic insights from Down syndrome

PubMed Central

Wiseman, Frances K.; Al-Janabi, Tamara; Hardy, John; Karmiloff-Smith, Annette; Nizetic, Dean; Tybulewicz, Victor L. J.; Fisher, Elizabeth M. C.; Strydom, André

2015-01-01

Down syndrome, which arises in individuals carrying an extra copy of chromosome 21, is associated with a greatly increased risk of early-onset Alzheimer disease. It is thought that this risk is conferred by the presence of three copies of the gene encoding amyloid precursor protein (APP) — an Alzheimer disease risk factor — although the possession of extra copies of other chromosome 21 genes may also play a part. Further study of the mechanisms underlying the development of Alzheimer disease in people with Down syndrome could provide insights into the mechanisms that cause dementia in the general population. PMID:26243569

Early onset type 2 diabetes: risk factors, clinical impact and management

PubMed Central

Idris, Iskandar

2014-01-01

Early onset type 2 diabetes mellitus (T2DM) is increasingly prevalent with a significant impact on the individual, healthcare service delivery and planning. The individuals are likely to be obese, lead a sedentary lifestyle, have a strong family history of T2DM, be of black and minority ethnic (BME) origin and come from a less affluent socioeconomic group. They have a heightened risk of developing microvascular and macrovascular complications, often at an earlier stage and with greater frequency than seen in type 1 diabetes. As such, early and aggressive risk factor management is warranted. Early onset T2DM is complex and impacts on service delivery with a need for multidisciplinary care of complications and comorbidities’, in addition to adequate educational and psychological support. This review on the impact of early onset T2DM provides the latest insights into this emerging epidemic. PMID:25364491

Central nervous system drug consumption depending on the time between symptom onset and the diagnosis of Alzheimer's disease: an analysis by the Registry of Dementias of Girona.

PubMed

Calvó-Perxas, Laia; López-Pousa, Secundino; Vilalta-Franch, Joan; Turró-Garriga, Oriol; Blankenburg, Michael; Febrer, Laia; Flaqué, Margarida; Vallmajó, Natàlia; Aguirregomozcorta, Maria; Genís, David; Casas, Isabel; Perkal, Héctor; Coromina, Joan; Garre-Olmo, Josep

2012-01-01

To describe central nervous system (CNS) drug consumption patterns depending on the time to diagnosis of Alzheimer's disease (AD), and to check whether the cases diagnosed later are associated with greater severity and consuming more CNS drugs. Cross-sectional study using 952 cases of the Registry of Dementias of Girona. A binary logistic regression was used to detect variables associated with the use of CNS drugs depending on the time to diagnosis. CNS drugs were consumed by 95.8% of the AD patients. Only antipsychotics presented a statistically significant increase in the frequency of prescription to patients with longer time elapsed from symptom onset to AD diagnosis. Longer time elapsed from the onset of symptoms to the diagnosis resulted in increased probability of antipsychotic consumption. Copyright © 2012 S. Karger AG, Basel.

Late-Onset Alzheimer's Disease Polygenic Risk Profile Score Predicts Hippocampal Function.

PubMed

Xiao, Ena; Chen, Qiang; Goldman, Aaron L; Tan, Hao Yang; Healy, Kaitlin; Zoltick, Brad; Das, Saumitra; Kolachana, Bhaskar; Callicott, Joseph H; Dickinson, Dwight; Berman, Karen F; Weinberger, Daniel R; Mattay, Venkata S

2017-11-01

We explored the cumulative effect of several late-onset Alzheimer's disease (LOAD) risk loci using a polygenic risk profile score (RPS) approach on measures of hippocampal function, cognition, and brain morphometry. In a sample of 231 healthy control subjects (19-55 years of age), we used an RPS to study the effect of several LOAD risk loci reported in a recent meta-analysis on hippocampal function (determined by its engagement with blood oxygen level-dependent functional magnetic resonance imaging during episodic memory) and several cognitive metrics. We also studied effects on brain morphometry in an overlapping sample of 280 subjects. There was almost no significant association of LOAD-RPS with cognitive or morphometric measures. However, there was a significant negative relationship between LOAD-RPS and hippocampal function (familywise error [small volume correction-hippocampal region of interest] p < .05). There were also similar associations for risk score based on APOE haplotype, and for a combined LOAD-RPS + APOE haplotype risk profile score (p < .05 familywise error [small volume correction-hippocampal region of interest]). Of the 29 individual single nucleotide polymorphisms used in calculating LOAD-RPS, variants in CLU, PICALM, BCL3, PVRL2, and RELB showed strong effects (p < .05 familywise error [small volume correction-hippocampal region of interest]) on hippocampal function, though none survived further correction for the number of single nucleotide polymorphisms tested. There is a cumulative deleterious effect of LOAD risk genes on hippocampal function even in healthy volunteers. The effect of LOAD-RPS on hippocampal function in the relative absence of any effect on cognitive and morphometric measures is consistent with the reported temporal characteristics of LOAD biomarkers with the earlier manifestation of synaptic dysfunction before morphometric and cognitive changes. Copyright © 2017 Society of Biological Psychiatry. All rights reserved.

Type 2 diabetes aggravates Alzheimer's disease-associated vascular alterations of the aorta in mice.

PubMed

Sena, Cristina M; Pereira, Ana M; Carvalho, Cristina; Fernandes, Rosa; Seiça, Raquel M; Oliveira, Catarina R; Moreira, Paula I

2015-01-01

Vascular risk factors are associated with a higher incidence of dementia. In fact, diabetes mellitus is considered a main risk factor for Alzheimer's disease (AD) and both diseases are characterized by vascular dysfunction. However, the underlying mechanisms remain largely unknown. Here, the effects of high-sucrose-induced type 2 diabetes (T2D) in the aorta of wild type (WT) and triple-transgenic AD (3xTg-AD) mice were investigated. 3xTg-AD mice showed a significant decrease in body weight and an increase in postprandial glycemia, glycated hemoglobin (HbA1c), and vascular nitrotyrosine, superoxide anion (O2•-), receptor for the advanced glycation end products (RAGE) protein, and monocyte chemoattractant protein-1 (MCP-1) levels when compared to WT mice. High-sucrose intake caused a significant increase in body weight, postprandial glycemia, HbA1c, triglycerides, plasma vascular cell adhesion molecule 1 (VCAM-1), and vascular nitrotyrosine, O2•-, RAGE, and MCP-1 levels in both WT and 3xTg-AD mice when compared to the respective control group. Also, a significant decrease in nitric oxide-dependent vasorelaxation was observed in 3xTg-AD and sucrose-treated WT mice. In conclusion, AD and T2D promote similar vascular dysfunction of the aorta, this effect being associated with elevated oxidative and nitrosative stress and inflammation. Also, AD-associated vascular alterations are potentiated by T2D. These findings support the idea that metabolic alterations predispose to the onset and progression of dementia.

Neuropathologic assessment of participants in two multi-center longitudinal observational studies: the Alzheimer Disease Neuroimaging Initiative (ADNI) and the Dominantly Inherited Alzheimer Network (DIAN).

PubMed

Cairns, Nigel J; Perrin, Richard J; Franklin, Erin E; Carter, Deborah; Vincent, Benjamin; Xie, Mingqiang; Bateman, Randall J; Benzinger, Tammie; Friedrichsen, Karl; Brooks, William S; Halliday, Glenda M; McLean, Catriona; Ghetti, Bernardino; Morris, John C

2015-08-01

It has been hypothesized that the relatively rare autosomal dominant Alzheimer disease (ADAD) may be a useful model of the more frequent, sporadic, late-onset AD (LOAD). Individuals with ADAD have a predictable age at onset and the biomarker profile of ADAD participants in the preclinical stage may be used to predict disease progression and clinical onset. However, the extent to which the pathogenesis and neuropathology of ADAD overlaps with that of LOAD is equivocal. To address this uncertainty, two multicenter longitudinal observational studies, the Alzheimer Disease Neuroimaging Initiative (ADNI) and the Dominantly Inherited Alzheimer Network (DIAN), leveraged the expertise and resources of the existing Knight Alzheimer Disease Research Center (ADRC) at Washington University School of Medicine, St. Louis, Missouri, USA, to establish a Neuropathology Core (NPC). The ADNI/DIAN-NPC is systematically examining the brains of all participants who come to autopsy at the 59 ADNI sites in the USA and Canada and the 14 DIAN sites in the USA (eight), Australia (three), UK (one) and Germany (two). By 2014, 41 ADNI and 24 DIAN autopsies (involving nine participants and 15 family members) had been performed. The autopsy rate in the ADNI cohort in the most recent year was 93% (total since NPC inception: 70%). In summary, the ADNI/DIAN NPC has implemented a standard protocol for all sites to solicit permission for brain autopsy and to send brain tissue to the NPC for a standardized, uniform and state-of-the-art neuropathologic assessment. The benefit to ADNI and DIAN of the implementation of the NPC is very clear. The NPC provides final "gold standard" neuropathological diagnoses and data against which the antecedent observations and measurements of ADNI and DIAN can be compared. © 2015 Japanese Society of Neuropathology.

A transgenic Alzheimer rat with plaques, tau pathology, behavioral impairment, oligomeric aβ, and frank neuronal loss.

PubMed

Cohen, Robert M; Rezai-Zadeh, Kavon; Weitz, Tara M; Rentsendorj, Altan; Gate, David; Spivak, Inna; Bholat, Yasmin; Vasilevko, Vitaly; Glabe, Charles G; Breunig, Joshua J; Rakic, Pasko; Davtyan, Hayk; Agadjanyan, Michael G; Kepe, Vladimir; Barrio, Jorge R; Bannykh, Serguei; Szekely, Christine A; Pechnick, Robert N; Town, Terrence

2013-04-10

Alzheimer's disease (AD) is hallmarked by amyloid plaques, neurofibrillary tangles, and widespread cortical neuronal loss (Selkoe, 2001). The "amyloid cascade hypothesis" posits that cerebral amyloid sets neurotoxic events into motion that precipitate Alzheimer dementia (Hardy and Allsop, 1991). Yet, faithful recapitulation of all AD features in widely used transgenic (Tg) mice engineered to overproduce Aβ peptides has been elusive. We have developed a Tg rat model (line TgF344-AD) expressing mutant human amyloid precursor protein (APPsw) and presenilin 1 (PS1ΔE9) genes, each independent causes of early-onset familial AD. TgF344-AD rats manifest age-dependent cerebral amyloidosis that precedes tauopathy, gliosis, apoptotic loss of neurons in the cerebral cortex and hippocampus, and cognitive disturbance. These results demonstrate progressive neurodegeneration of the Alzheimer type in these animals. The TgF344-AD rat fills a critical need for a next-generation animal model to enable basic and translational AD research.

Caregiver burden in Alzheimer-type dementia and psychosis: A comparative study from India.

PubMed

Sinha, P; Desai, N G; Prakash, O; Kushwaha, S; Tripathi, C B

2017-04-01

Caregiver burden in dementia is an important area of research. Providing care for a relative can be a potent source of chronic stress and can have deleterious consequences for both the physical and emotional health of caregivers. This study aims to evaluate the burden of care in caregivers of patients with Alzheimer-type dementia and compare it with elderly psychosis; and to also study the factors that influence burden of care in Alzheimer's dementia. Thirty-two caregiver-patient dyads of Alzheimer-type dementia were compared with thirty-two caregiver-patient dyads of psychosis. Cognitive assessment, abilities to perform activities of daily living and severity of dementia was assessed in the patients. Zarit Burden Interview was used to study the caregiver burden in both groups. The mean burden score in dementia caregivers was high at 47.7, whereas the mean burden score for elderly psychosis caregivers was lesser at 33.6, and this difference in mean burden scores was found to be statistically significant. Spouses had the highest mean burden scores of 53.48. Caregiver burden in dementia was positively correlated with cognitive impairment and inability to carry out ADLs. Presence of psychological distress in caregivers was also an indicator for greater caregiver burden in dementia. The study revealed that dementia carries a greater caregiver burden when compared with elderly patients with psychosis. Innovative interventions are needed to remove burden from caregiving, making it a meaningful practice integral to the Indian society. Copyright © 2017 Elsevier B.V. All rights reserved.

White matter hyperintensities are a core feature of Alzheimer's disease: Evidence from the dominantly inherited Alzheimer network.

PubMed

Lee, Seonjoo; Viqar, Fawad; Zimmerman, Molly E; Narkhede, Atul; Tosto, Giuseppe; Benzinger, Tammie L S; Marcus, Daniel S; Fagan, Anne M; Goate, Alison; Fox, Nick C; Cairns, Nigel J; Holtzman, David M; Buckles, Virginia; Ghetti, Bernardino; McDade, Eric; Martins, Ralph N; Saykin, Andrew J; Masters, Colin L; Ringman, John M; Ryan, Natalie S; Förster, Stefan; Laske, Christoph; Schofield, Peter R; Sperling, Reisa A; Salloway, Stephen; Correia, Stephen; Jack, Clifford; Weiner, Michael; Bateman, Randall J; Morris, John C; Mayeux, Richard; Brickman, Adam M

2016-06-01

White matter hyperintensities (WMHs) are areas of increased signal on T2-weighted magnetic resonance imaging (MRI) scans that most commonly reflect small vessel cerebrovascular disease. Increased WMH volume is associated with risk and progression of Alzheimer's disease (AD). These observations are typically interpreted as evidence that vascular abnormalities play an additive, independent role contributing to symptom presentation, but not core features of AD. We examined the severity and distribution of WMH in presymptomatic PSEN1, PSEN2, and APP mutation carriers to determine the extent to which WMH manifest in individuals genetically determined to develop AD. The study comprised participants (n = 299; age = 39.03 ± 10.13) from the Dominantly Inherited Alzheimer Network, including 184 (61.5%) with a mutation that results in AD and 115 (38.5%) first-degree relatives who were noncarrier controls. We calculated the estimated years from expected symptom onset (EYO) by subtracting the affected parent's symptom onset age from the participant's age. Baseline MRI data were analyzed for total and regional WMH. Mixed-effects piece-wise linear regression was used to examine WMH differences between carriers and noncarriers with respect to EYO. Mutation carriers had greater total WMH volumes, which appeared to increase approximately 6 years before expected symptom onset. Effects were most prominent for the parietal and occipital lobe, which showed divergent effects as early as 22 years before estimated onset. Autosomal-dominant AD is associated with increased WMH well before expected symptom onset. The findings suggest the possibility that WMHs are a core feature of AD, a potential therapeutic target, and a factor that should be integrated into pathogenic models of the disease. Ann Neurol 2016;79:929-939. © 2016 American Neurological Association.

Neurological manifestations of autosomal dominant familial Alzheimer's disease: a comparison of the published literature with the Dominantly Inherited Alzheimer Network observational study (DIAN-OBS).

PubMed

Tang, Mengxuan; Ryman, Davis C; McDade, Eric; Jasielec, Mateusz S; Buckles, Virginia D; Cairns, Nigel J; Fagan, Anne M; Goate, Alison; Marcus, Daniel S; Xiong, Chengjie; Allegri, Ricardo F; Chhatwal, Jasmeer P; Danek, Adrian; Farlow, Martin R; Fox, Nick C; Ghetti, Bernardino; Graff-Radford, Neill R; Laske, Christopher; Martins, Ralph N; Masters, Colin L; Mayeux, Richard P; Ringman, John M; Rossor, Martin N; Salloway, Stephen P; Schofield, Peter R; Morris, John C; Bateman, Randall J

2016-12-01

Autosomal dominant familial Alzheimer's disease (ADAD) is a rare disorder with non-amnestic neurological symptoms in some clinical presentations. We aimed to compile and compare data from symptomatic participants in the Dominantly Inherited Alzheimer Network observational study (DIAN-OBS) with those reported in the literature to estimate the prevalences of non-amnestic neurological symptoms in participants with ADAD. We prospectively collected data from the DIAN-OBS database, which recruited participants from study centres in the USA, Europe, and Australia, between Feb 29, 2008, and July 1, 2014. We also did a systematic review of publications to extract individual-level clinical data for symptomatic participants with ADAD. We used data for age of onset (from first report of cognitive decline), disease course from onset to death, and the presence of 13 neurological findings that have been reported in association with ADAD. Using multivariable linear regression, we investigated the prevalences of various non-amnestic neurological symptoms and the contributions of age of onset and specific mutation type on symptoms. The DIAN-OBS dataset included 107 individuals with detailed clinical data (forming the DIAN-OBS cohort). Our systematic review yielded 188 publications reporting on 1228 symptomatic individuals, with detailed neurological examination descriptions available for 753 individuals (forming the published data cohort). The most prevalent non-amnestic cognitive manifestations in participants in the DIAN-OBS cohort were those typical of mild to moderate Alzheimer's disease, including visual agnosia (55·1%, 95% CI 45·7-64·6), aphasia (57·9%, 48·6-67·3), and behavioural changes (61·7%, 51·5-70·0). Non-amnestic cognitive manifestations were less prevalent in the published data cohort (eg, visual agnosia [5·6%, 3·9-7·2], aphasia [23·0%, 20·0-26·0], and behavioural changes [31·7%, 28·4-35·1]). Prevalence of non-cognitive neurological manifestations in

Association between polymorphisms of the insulin-degrading enzyme gene and late-onset Alzheimer disease.

PubMed

Wang, Shitao; He, Feiyan; Wang, Ying

2015-06-01

The insulin-degrading enzyme (IDE) gene is a strong positional and biological candidate for late-onset Alzheimer disease (LOAD) susceptibility, with recent studies independently demonstrating an association between IDE gene variants and LOAD. However, previous data have been controversial. To investigate the relationship between IDE gene polymorphisms and LOAD risk, a case-control association study of 406 Han Chinese participants in Xinjiang, China, was undertaken. The LOAD and control groups consisted of 202 and 204 participants, respectively. The single-nucleotide polymorphisms rs1887922 and rs1999764 of the IDE gene were linked to LOAD incidence. The presence of the CT+CC genotype of rs1999764 had a protective effect compared to the TT genotype (adjusted P=.0001; odds ratio [OR]=0.226; 95% confidence interval [CI]=0.116-0.441), while the CT+CC genotype of rs1887922 was associated with increased LOAD risk (adjusted P=.0001; OR=3.640; 95% CI=1.889-7.016). Moreover, the effects of rs1887922 and rs1999764 were associated with LOAD risk independent of the apolipoprotein E ∊4 polymorphism and were more significant in men and women, respectively. These results demonstrate that the polymorphisms rs1887922 and rs1999764 of the IDE gene are associated with LOAD susceptibility in the Xinjiang Han population. © The Author(s) 2014.

Elevation of neuropeptide Y (NPY) in substantia innominata in Alzheimer's type dementia.

PubMed

Allen, J M; Ferrier, I N; Roberts, G W; Cross, A J; Adrian, T E; Crow, T J; Bloom, S R

1984-06-01

Concentrations of neuropeptide Y (NPY) have been determined in 12 areas of control brains and compared to those found in brains from patients with Alzheimer's type dementia (ATD). The distribution of NPY in the control brains was compared with those reported previously. Highest concentrations were identified in the subcortical structures, in particular, nucleus accumbens (203 +/- 21.7 pmol/g), amygdala (136.7 +/- 15.8 pmol/g), and substantia innominata (109.0 +/- 12.6 pmol/g). A significant elevation in NPY concentrations was identified in the region of the substantia innominata of Alzheimer brains (controls: 109.0 +/- 12.6 pmol/g, ATD: 206 +/- 28.2 pmol/g, P less than 0.001). This change in NPY concentration was similar to the increase in somatostatin concentration in this region of ATD brain. In contrast, although cortical concentrations of somatostatin were reduced in ATD, no change was found in the concentrations of NPY in the 4 regions of cerebral cortex and the remaining subcortical areas examined.

Exploring the nexus of Alzheimer's disease and related dementias with cancer and cancer therapies: A convening of the Alzheimer's Association & Alzheimer's Drug Discovery Foundation.

PubMed

Snyder, Heather M; Ahles, Tim; Calderwood, Stuart; Carrillo, Maria C; Chen, Honglei; Chang, Chung-Chou H; Craft, Suzanne; De Jager, Philip; Driver, Jane A; Fillit, Howard; Knopman, David; Lotze, Michael; Tierney, Mary C; Petanceska, Suzana; Saykin, Andrew; Seshadri, Sudha; Shineman, Diana; Ganguli, Mary

2017-03-01

Recent population studies suggest an intriguing inverse relationship between several types of cancer and neurodegenerative diseases, including Alzheimer's disease. Understanding the intersection of the underlying biology for these two distinct families of diseases with one another may offer novel approaches to identify new therapeutic approaches and possible opportunities to repurpose existing drug candidates. The Alzheimer's Association and the Alzheimer's Drug Discovery Foundation convened a one-day workshop to delve into this discussion. Workshop participants outlined research focus areas, potential collaborations, and partnerships for future action. Copyright © 2016 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Curcumin and Apigenin – novel and promising therapeutics against chronic neuroinflammation in Alzheimer's disease

PubMed Central

Venigalla, Madhuri; Gyengesi, Erika; Münch, Gerald

2015-01-01

Alzheimer's disease is a progressive neurodegenerative disorder, characterized by deposition of amyloid beta, neurofibrillary tangles, astrogliosis and microgliosis, leading to neuronal dysfunction and loss in the brain. Current treatments for Alzheimer's disease primarily focus on enhancement of cholinergic transmission. However, these treatments are only symptomatic, and no disease-modifying drug is available for Alzheimer's disease patients. This review will provide an overview of the proven antioxidant, anti-inflammatory, anti-amyloidogenic, neuroprotective, and cognition-enhancing effects of curcumin and apigenin and discuss the potential of these compounds for Alzheimer's disease prevention and treatment. We suggest that these compounds might delay the onset of Alzheimer's disease or slow down its progression, and they should enter clinical trials as soon as possible. PMID:26487830

The intricate association between gut microbiota and development of type 1, type 2 and type 3 diabetes.

PubMed

Bekkering, Pjotr; Jafri, Ismael; van Overveld, Frans J; Rijkers, Ger T

2013-11-01

It has been proposed that changes in the composition of gut microbiota contribute to the development of diabetes Types 1, 2 and 3 (the latter known as Alzheimer's disease). The onset of these diseases is affected by complex interactions of genetic and several environmental factors. Alterations in gut microbiota in combination with specific diets can result in increased intestinal permeability leading via a continuous state of low-grade inflammation to the development of insulin resistance. Since a change in composition of gut microbiota is also suggested to be the underlying factor for the development of obesity, it is obvious to link gut microbiota with the pathogenesis of diabetes. In addition, insulin resistance in the brain has been recently associated with Alzheimer's disease. These new paradigms in combination with data from studies with prebiotics and probiotics may lead to a novel way to control and even prevent diabetes in general.

Genetic dissection of Alzheimer disease, a heterogeneous disorder.

PubMed

Schellenberg, G D

1995-09-12

The genetics of Alzheimer disease (AD) are complex and not completely understood. Mutations in the amyloid precursor protein gene (APP) can cause early-onset autosomal dominant AD. In vitro studies indicate that cells expressing mutant APPs overproduce pathogenic forms of the A beta peptide, the major component of AD amyloid. However, mutations in the APP gene are responsible for 5% or less of all early-onset familial AD. A locus on chromosome 14 is responsible for AD in other early-onset AD families and represents the most severe form of the disease in terms of age of onset and rate of decline. Attempts to identify the AD3 gene by positional cloning methods are underway. At least one additional early-onset AD locus remains to be located. In late-onset AD, the apolipoprotein E gene allele epsilon 4 is a risk factor for AD. This allele appears to act as a dose-dependent age-of-onset modifier. The epsilon 2 allele of this gene may be protective. Other late-onset susceptibility factors remain to be identified.

Early-onset facioscapulohumeral muscular dystrophy type 1 with some atypical features.

PubMed

Dorobek, Małgorzata; van der Maarel, Silvère M; Lemmers, Richard J L F; Ryniewicz, Barbara; Kabzińska, Dagmara; Frants, Rune R; Gawel, Malgorzata; Walecki, Jerzy; Hausmanowa-Petrusewicz, Irena

2015-04-01

Facioscapulohumeral muscular dystrophy cases with facial weakness before the age of 5 and signs of shoulder weakness by the age of 10 are defined as early onset. Contraction of the D4Z4 repeat on chromosome 4q35 is causally related to facioscapulohumeral muscular dystrophy type 1, and the residual size of the D4Z4 repeat shows a roughly inverse correlation with the severity of the disease. Contraction of the D4Z4 repeat on chromosome 4q35 is believed to induce a local change in chromatin structure and consequent transcriptional deregulation of 4qter genes. We present early-onset cases in the Polish population that amounted to 21% of our total population with facioscapulohumeral muscular dystrophy. More than 27% of them presented with severe phenotypes (wheelchair dependency). The residual D4Z4 repeat sizes ranged from 1 to 4 units. In addition, even within early-onset facioscapulohumeral muscular dystrophy type 1 phenotypes, some cases had uncommon features (head drop, early disabling contractures, progressive ptosis, and respiratory insufficiency and cardiomyopathy). © The Author(s) 2014.

R47H Variant of TREM2 Associated With Alzheimer Disease in a Large Late-Onset Family

PubMed Central

Korvatska, Olena; Leverenz, James B.; Jayadev, Suman; McMillan, Pamela; Kurtz, Irina; Guo, Xindi; Rumbaugh, Malia; Matsushita, Mark; Girirajan, Santhosh; Dorschner, Michael O.; Kiianitsa, Kostantin; Yu, Chang-En; Brkanac, Zoran; Garden, Gwenn A.; Raskind, Wendy H.; Bird, Thomas D.

2016-01-01

Importance The R47H variant in the triggering receptor expressed on myeloid cells 2 gene (TREM2), a modulator of the immune response of microglia, is a strong genetic risk factor for Alzheimer disease (AD) and possibly other neurodegenerative disorders. Objective To investigate a large family with late-onset AD (LOAD), in which R47H cosegregated with 75% of cases. Design, Setting, and Participants This study includes genetic and pathologic studies of families with LOAD from 1985 to 2014. A total of 131 families with LOAD (751 individuals) were included from the University of Washington Alzheimer Disease Research Center. To identify LOAD genes/risk factors in the LOAD123 family with 21 affected members and 12 autopsies, we sequenced 4 exomes. Candidate variants were tested for cosegregation with the disease. TREM2 R47H was genotyped in an additional 130 families with LOAD. We performed clinical and neuropathological assessments of patients with and without R47H and evaluated the variant's effect on brain pathology, cellular morphology, and expression of microglial markers. Main Outcomes and Measures We assessed the effect of TREM2 genotype on age at onset and disease duration. We compared Braak and Consortium to Establish a Registry for Alzheimer's Disease scores, presence of α-synuclein and TAR DNA-binding protein 43 aggregates, and additional vascular or Parkinson pathology in TREM2 R47H carriers vs noncarriers. Microglial activation was assessed by quantitative immunohistochemistry and morphometry. Results Twelve of 16 patients with AD in the LOAD123 family carried R47H. Eleven patients with dementia had apolipoprotein E 4 (ApoE4) and R47H genotypes. We also found a rare missense variant, D353N, in a nominated AD risk gene, unc-5 homolog C (UNC5C), in 5 affected individuals in the LOAD123 family. R47H carriers demonstrated a shortened disease duration (mean [SD], 6.7 [2.8] vs 11.1 [6.6] years; 2-tailed t test; P = .04) and more frequent α-synucleinopathy. The

Alzheimer's disease and other neurological disorders.

PubMed

Henderson, V W

2007-10-01

Menopausal status and estrogen-containing hormone therapy may influence several neurological disorders, including Alzheimer's disease, epilepsy, migraine headache, multiple sclerosis, Parkinson's disease, sleep disorders, and stroke. For most of these illnesses, evidence on hormone therapy is insufficient to guide practice decisions. For stroke, clinical trial evidence indicates that hormone therapy increases risk of cerebral infarction. For women with Alzheimer's disease, estrogen treatment trials have tended to be small and of short duration. Most suggest that estrogen started after the onset of dementia symptoms does not meaningfully improve cognition or slow disease progression. Hormone therapy initiated after age 64 increased all-cause dementia in the Women's Health Initiative Memory Study. Many observational studies, however, report protective associations between hormone use and Alzheimer risk. Apparent risk reduction may represent a bias toward hormone therapy, since hormones are more often prescribed to healthier women. However, when compared to the Women's Health Initiative Memory Study, estrogen exposures in many observational studies reflect hormone initiation at a younger age, closer to the time of menopause. One intriguing hypothesis is that hormone therapy initiated or used during an early critical window may reduce later Alzheimer incidence. Public health implications of this hypothesis are important, but current data are inadequate to decide the issue.

Inbreeding among Caribbean Hispanics from the Dominican Republic and its effects on risk of Alzheimer disease.

PubMed

Vardarajan, Badri N; Schaid, Daniel J; Reitz, Christiane; Lantigua, Rafael; Medrano, Martin; Jiménez-Velázquez, Ivonne Z; Lee, Joseph H; Ghani, Mahdi; Rogaeva, Ekaterina; St George-Hyslop, Peter; Mayeux, Richard P

2015-08-01

Inbreeding can be associated with a modification of disease risk due to excess homozygosity of recessive alleles affecting a wide range of phenotypes. We estimated the inbreeding coefficient in Caribbean Hispanics and examined its effects on risk of late-onset Alzheimer disease. The inbreeding coefficient was calculated in 3,392 subjects (1,451 late-onset Alzheimer disease patients and 1,941 age-matched healthy controls) of Caribbean Hispanic ancestry using 177,997 nearly independent single-nucleotide polymorphisms from genome-wide array. The inbreeding coefficient was estimated using the excess homozygosity method with and without adjusting for admixture. The average inbreeding coefficient in Caribbean Hispanics without accounting for admixture was F = 0.018 (±0.048), suggesting a mating equivalent to that of second cousins or second cousins once removed. Adjusting for admixture from three parent populations, the average inbreeding coefficient was found to be 0.0034 (±0.019) or close to third-cousin mating. Inbreeding coefficient was a significant predictor of Alzheimer disease when age, sex, and APOE genotype were used as adjusting covariates (P = 0.03). The average inbreeding coefficient of this population is significantly higher than that of the general Caucasian populations in North America. The high rate of inbreeding resulting in increased frequency of recessive variants is advantageous for the identification of rare variants associated with late-onset Alzheimer disease.Genet Med 17 8, 639-643.

Early vs late age at onset frontotemporal dementia and frontotemporal lobar degeneration.

PubMed

Seo, Sang Won; Thibodeau, Marie-Pierre; Perry, David C; Hua, Alice; Sidhu, Manu; Sible, Isabel; Vargas, Jose Norberto S; Gaus, Stephanie E; Rabinovici, Gil D; Rankin, Katherine D; Boxer, Adam L; Kramer, Joel H; Rosen, Howard J; Gorno-Tempini, Maria Luisa; Grinberg, Lea T; Huang, Eric J; DeArmond, Stephen J; Trojanowski, John Q; Miller, Bruce L; Seeley, William W

2018-03-20

To examine clinicopathologic correlations in early vs late age at onset frontotemporal dementia (FTD) and frontotemporal lobar degeneration (FTLD). All patients were clinically evaluated and prospectively diagnosed at the UCSF Memory and Aging Center. Two consecutive series were included: (1) patients with a clinically diagnosed FTD syndrome who underwent autopsy (cohort 1) and (2) patients with a primary pathologic diagnosis of FTLD, regardless of the clinical syndrome (cohort 2). These series were divided by age at symptom onset (cutoff 65 years). In cohort 1, 48 (25.3%) were 65 years or older at symptom onset. Pathologic causes of behavioral variant FTD (bvFTD) were similar in the early age at onset (EO) and late age at onset (LO) bvFTD groups. In corticobasal syndrome (CBS), however, the most common pathologic substrate differed according to age at onset: progressive supranuclear palsy (42.9%) in LO-CBS and Alzheimer disease (AD; 40.7%) in EO-CBS. In cohort 2, 57 (28.4%) were classified as LO-FTLD. Regarding FTLD major molecular classes, FTLD with transactive response DNA-binding protein of 43 kDa was most common in EO-FTLD (44.4%), whereas FTLD-tau (58.3%) was most common in LO-FTLD. Antemortem diagnosis of a non-FTD syndrome, usually AD-type dementia, was more frequent in LO-FTLD than EO-FTLD (19.3% vs 7.7%, p = 0.017). LO-FTLD was also associated with more prevalent comorbid pathologic changes. Of these, moderate to severe AD neuropathologic change and argyrophilic grain disease were overrepresented among patients who received an antemortem diagnosis of AD-type dementia. Patients with FTD and FTLD often develop symptoms after age 65, and age at onset represents an important consideration when making antemortem neuropathologic predictions. © 2018 American Academy of Neurology.

A novel presenilin 1 mutation (L174 M) in a large Cuban family with early onset Alzheimer disease.

PubMed

Bertoli Avella, A M; Marcheco Teruel, B; Llibre Rodriguez, J J; Gomez Viera, N; Borrajero Martinez, I; Severijnen, E A; Joosse, M; van Duijn, C M; Heredero Baute, L; Heutink, P

2002-10-01

We studied a Cuban family with presenile dementia (autosomal dominant) consisting of 281 members within six generations, the proband descended from a Spanish founder. Mean age at onset was 59 years of age. Memory impairment was the main symptom in all patients, additionally, ischemic episodes were described in 4 (n = 18) patients. Neuropathological examination of brain material (1 patient) revealed neuronal loss, amyloid plaques, and neurofibrillary tangles. Thirty DNA samples were genotyped (regions on chromosome 1, 3, 10, 12, 14, 17, 19, 20, and 21). A maximum Lod score of 3.79 at theta = 0 was obtained for marker D14S43, located in a 9-cM interval in which all patients shared the same haplotype. Sequencing of the PSEN1 gene revealed a heterozygous base substitution, C520A (exon 6), which is predicted to cause an amino acid change from leucine to methionine in the TMIII of the presenilin 1 protein. The mutation was found to co-segregate with the disease phenotype and the associated disease haplotype. The C --> A change was not observed in 80 control chromosomes from the Cuban population. Leucine at position 174 is highly conserved among species and is identical in presenilin 1 and presenilin 2 proteins. We propose the L174 M mutation might lead to an abnormal N-terminal and probably C-terminal fragments and malfunction of the protein complex. In conclusion, we found a novel PSEN1 mutation in a large family with clinical and pathological diagnosis of early onset familial Alzheimer disease, which may be relevant for other Hispanic populations.

Whole Exome Analysis of Early Onset Alzheimer’s Disease

DTIC Science & Technology

2015-04-01

autosomal recessive early-onset Parkinson’s disease and juvenile Parkinson disease , Parkin has been shown to promote intracellular Abeta1–42 clearance [15... Parkinsonism . Conclusions Mutations were found in 6/50 families. The presence of an APOE-4 allele may account for disease status in one affected non...AD_________________ Award Number: W81XWH-12-1-0013 TITLE: Whole Exome Analysis of Early Onset Alzheimer’s Disease PRINCIPAL INVESTIGATOR

Neuropsychiatric subsyndromes and brain metabolic network dysfunctions in early onset Alzheimer's disease.

PubMed

Ballarini, Tommaso; Iaccarino, Leonardo; Magnani, Giuseppe; Ayakta, Nagehan; Miller, Bruce L; Jagust, William J; Gorno-Tempini, Maria Luisa; Rabinovici, Gil D; Perani, Daniela

2016-12-01

Neuropsychiatric symptoms (NPSs) often occur in early-age-of-onset Alzheimer's disease (EOAD) and cluster into sub-syndromes (SSy). The aim of this study was to investigate the association between 18 F-FDG-PET regional and connectivity-based brain metabolic dysfunctions and neuropsychiatric SSy. NPSs were assessed in 27 EOAD using the Neuropsychiatric Inventory and further clustered into four SSy (apathetic, hyperactivity, affective, and psychotic SSy). Eighty-five percent of EOAD showed at least one NPS. Voxel-wise correlations between SSy scores and brain glucose metabolism (assessed with 18 F-FDG positron emission tomography) were studied. Interregional correlation analysis was used to explore metabolic connectivity in the salience (aSN) and default mode networks (DMN) in a larger sample of EOAD (N = 51) and Healthy Controls (N = 57). The apathetic, hyperactivity, and affective SSy were highly prevalent (>60%) as compared to the psychotic SSy (33%). The hyperactivity SSy scores were associated with increase of glucose metabolism in frontal and limbic structures, implicated in behavioral control. A comparable positive correlation with part of the same network was found for the affective SSy scores. On the other hand, the apathetic SSy scores were negatively correlated with metabolism in the bilateral orbitofrontal and dorsolateral frontal cortex known to be involved in motivation and decision-making processes. Consistent with these SSy regional correlations with brain metabolic dysfunction, the connectivity analysis showed increases in the aSN and decreases in the DMN. Behavioral abnormalities in EOAD are associated with specific dysfunctional changes in brain metabolic activity, in particular in the aSN that seems to play a crucial role in NPSs in EOAD. Hum Brain Mapp 37:4234-4247, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Epigenetics in Alzheimer's Disease: Perspective of DNA Methylation.

PubMed

Qazi, Talal Jamil; Quan, Zhenzhen; Mir, Asif; Qing, Hong

2018-02-01

Research over the years has shown that causes of Alzheimer's disease are not well understood, but over the past years, the involvement of epigenetic mechanisms in the developing memory formation either under pathological or physiological conditions has become clear. The term epigenetics represents the heredity of changes in phenotype that are independent of altered DNA sequences. Different studies validated that cytosine methylation of genomic DNA decreases with age in different tissues of mammals, and therefore, the role of epigenetic factors in developing neurological disorders in aging has been under focus. In this review, we summarized and reviewed the involvement of different epigenetic mechanisms especially the DNA methylation in Alzheimer's disease (AD), late-onset Alzheimer's disease (LOAD), familial Alzheimer's disease (FAD), and autosomal dominant Alzheimer's disease (ADAD). Down to the minutest of details, we tried to discuss the methylation patterns like mitochondrial DNA methylation and ribosomal DNA (rDNA) methylation. Additionally, we mentioned some therapeutic approaches related to epigenetics, which could provide a potential cure for AD. Moreover, we reviewed some recent studies that validate DNA methylation as a potential biomarker and its role in AD. We hope that this review will provide new insights into the understanding of AD pathogenesis from the epigenetic perspective especially from the perspective of DNA methylation.

"Boomerang Neuropathology" of Late-Onset Alzheimer's Disease is Shrouded in Harmful "BDDS": Breathing, Diet, Drinking, and Sleep During Aging.

PubMed

Daulatzai, Mak Adam

2015-07-01

Brain damage begins years before substantial neurodegeneration and Alzheimer's dementia. Crucial fundamental activities of life are breathing, eating, drinking, and sleeping. When these pivotal functions are maligned over a prolonged period, they impart escalating dyshomeostasis. The latter may lead to disastrous consequences including cognitive dysfunction and Alzheimer's disease (AD). The current theme here is that multiple pathophysiological derangements are promoted over a prolonged period by the very fundamental activities of life-when "rendered unhealthy." They may converge on several regulating/modulating factors (e.g., mitochondrial energy production, oxidative stress, innate immunity, and vascular function) and promote insidious neuropathology that culminates in cognitive decline in the aged. This is of course associated with the accumulation of amyloid beta and phosphorylated tau in the brain. Epidemiological, biomarker, and neuroimaging studies have provided significant copious evidence on the presence of indolent prodromal AD neuropathology many years prior to symptomatic onset. Progressive oxidative damage to specific gene promoters may result in gene silencing. A mechanistic link may possibly exist between epigenomic state, DNA damage, and chronically unhealthy/dysfunctional body systems. This paper, therefore, addresses and delineates the deleterious pathophysiological impact triggered by dysfunctional breathing, harmful diet, excess of alcohol consumption, and sleep deprivation; indeed, their impact may alter epigenetic state. It is mandatory, therefore, to abrogate cognitive decline and attenuate AD pathology through adoption of a healthy lifestyle, in conjunction with combination therapy with known moderators of cognitive decline. This strategy may thwart multiple concurrent and synergistic pathologies, including epigenetic dysfunction. A multi-factorial therapeutic intervention is required to overcome wide ranging neuropathology and multi

The road to LOAD: late-onset Alzheimer's disease and a possible way to block it.

PubMed

Whitfield, James F

2007-10-01

The ageing brain becomes increasingly less able to destroy or eject toxic amyloid (A) beta42 peptide byproducts of normal neuronal activity that consequently accumulate to induce Alzheimer's disease (AD). Therefore, the various components of the Abeta-clearing machinery are prime targets for AD therapeutics. In this connection, there are reports that taking statins to lower circulating cholesterol to prevent cardiovascular disease can also prevent late-onset AD (LOAD) the most common form of the disease. However, it seems unlikely that statins would prevent LOAD by lowering the very long-lived brain cholesterol that is controlled independently from the very much shorter-lived circulating cholesterol. In fact, reducing the ability of the brain astrocytes to make cholesterol for their closely associated neuron clients' synaptogenesis could damage the brain rather than protect it. However, a plausible way statins might prevent LOAD is to target a main component of the clearance machinery, low-density lipoprotein receptor-related protein 1 (LRP1), the brain's powerful Abeta-efflux driver. This is indicated by a reported ability of micromolar concentrations of lovastatin and simvastatin to strongly stimulate brain vascular endothelial cells to make this Abeta ejector. Therefore, if this holds up, taking a statin over the years would prevent the normal decline of LRP1 in the ageing brain and a LOAD-driving accumulation of Abeta.

Revealing the role of glutathione S-transferase omega in age-at-onset of Alzheimer and Parkinson diseases.

PubMed

Li, Yi-Ju; Scott, William K; Zhang, Ling; Lin, Ping-I; Oliveira, Sofia A; Skelly, Tara; Doraiswamy, Maurali P; Welsh-Bohmer, Kathleen A; Martin, Eden R; Haines, Jonathan L; Pericak-Vance, Margaret A; Vance, Jeffery M

2006-08-01

We previously reported a linkage region on chromosome 10q for age-at-onset (AAO) of Alzheimer (AD) and Parkinson (PD) diseases. Glutathione S-transferase, omega-1 (GSTO1) and the adjacent gene GSTO2, located in this linkage region, were then reported to associate with AAO of AD and PD. To examine whether GSTO1 and GSTO2 (hereafter referred to as GSTO1h) are responsible for the linkage evidence, we identified 39 families in AD that lead to our previous linkage and association findings. The evidence of linkage and association was markedly diminished after removing these 39 families from the analyses, thus providing support that GSTO1h drives the original linkage results. The maximum average AAO delayed by GSTO1h SNP 7-1 (rs4825, A nucleotide) was 6.8 (+/-4.41) years for AD and 8.6(+/-5.71) for PD, respectively. This is comparable to the magnitude of AAO difference by APOE-4 in these same AD and PD families. These findings suggest the presence of genetic heterogeneity for GSTO1h's effect on AAO, and support GSTO1h's role in modifying AAO in these two disorders.

Genetic study of multimodal imaging Alzheimer's disease progression score implicates novel loci.

PubMed

Scelsi, Marzia A; Khan, Raiyan R; Lorenzi, Marco; Christopher, Leigh; Greicius, Michael D; Schott, Jonathan M; Ourselin, Sebastien; Altmann, Andre

2018-05-30

Identifying genetic risk factors underpinning different aspects of Alzheimer's disease has the potential to provide important insights into pathogenesis. Moving away from simple case-control definitions, there is considerable interest in using quantitative endophenotypes, such as those derived from imaging as outcome measures. Previous genome-wide association studies of imaging-derived biomarkers in sporadic late-onset Alzheimer's disease focused only on phenotypes derived from single imaging modalities. In contrast, we computed a novel multi-modal neuroimaging phenotype comprising cortical amyloid burden and bilateral hippocampal volume. Both imaging biomarkers were used as input to a disease progression modelling algorithm, which estimates the biomarkers' long-term evolution curves from population-based longitudinal data. Among other parameters, the algorithm computes the shift in time required to optimally align a subjects' biomarker trajectories with these population curves. This time shift serves as a disease progression score and it was used as a quantitative trait in a discovery genome-wide association study with n = 944 subjects from the Alzheimer's Disease Neuroimaging Initiative database diagnosed as Alzheimer's disease, mild cognitive impairment or healthy at the time of imaging. We identified a genome-wide significant locus implicating LCORL (rs6850306, chromosome 4; P = 1.03 × 10-8). The top variant rs6850306 was found to act as an expression quantitative trait locus for LCORL in brain tissue. The clinical role of rs6850306 in conversion from healthy ageing to mild cognitive impairment or Alzheimer's disease was further validated in an independent cohort comprising healthy, older subjects from the National Alzheimer's Coordinating Center database. Specifically, possession of a minor allele at rs6850306 was protective against conversion from mild cognitive impairment to Alzheimer's disease in the National Alzheimer's Coordinating Center cohort (hazard

Drawing Disorders in Alzheimer's Disease and Other Forms of Dementia.

PubMed

Trojano, Luigi; Gainotti, Guido

2016-04-21

Drawing is a multicomponential process that can be impaired by many kinds of brain lesions. Drawing disorders are very common in Alzheimer's disease and other forms of dementia, and can provide clinical information for the distinction of the different dementing diseases. In our review we started from an overview of the neural and cognitive bases of drawing, and from a recollection of the drawing tasks more frequently used for assessing individuals with dementia. Then, we analyzed drawing disorders in dementia, paying special attention to those observed in Alzheimer's disease, from the prodromal stages of the amnesic mild cognitive impairment to the stages of full-blown dementia, both in the sporadic forms with late onset in the entorhino-hippocampal structures and in those with early onset in the posterior neocortical structures. We reviewed the drawing features that could differentiate Alzheimer's disease from vascular dementia and from the most frequent forms of degenerative dementia, namely frontotemporal dementia and Lewy body disease. Finally, we examined some peculiar aspects of drawing disorders in dementia, such as perseverations, rotations, and closing-in. We argue that a careful analysis of drawing errors helps to differentiate the different forms of dementia more than overall accuracy in drawing.

Decreased body mass index in the preclinical stage of autosomal dominant Alzheimer's disease.

PubMed

Müller, Stephan; Preische, Oliver; Sohrabi, Hamid R; Gräber, Susanne; Jucker, Mathias; Dietzsch, Janko; Ringman, John M; Martins, Ralph N; McDade, Eric; Schofield, Peter R; Ghetti, Bernardino; Rossor, Martin; Graff-Radford, Neill R; Levin, Johannes; Galasko, Douglas; Quaid, Kimberly A; Salloway, Stephen; Xiong, Chengjie; Benzinger, Tammie; Buckles, Virginia; Masters, Colin L; Sperling, Reisa; Bateman, Randall J; Morris, John C; Laske, Christoph

2017-04-27

The relationship between body-mass index (BMI) and Alzheimer´s disease (AD) has been extensively investigated. However, BMI alterations in preclinical individuals with autosomal dominant AD (ADAD) have not yet been investigated. We analyzed cross-sectional data from 230 asymptomatic members of families with ADAD participating in the Dominantly Inherited Alzheimer Network (DIAN) study including 120 preclinical mutation carriers (MCs) and 110 asymptomatic non-carriers (NCs). Differences in BMI and their relation with cerebral amyloid load and episodic memory as a function of estimated years to symptom onset (EYO) were analyzed. Preclinical MCs showed significantly lower BMIs compared to NCs, starting 11.2 years before expected symptom onset. However, the BMI curves begun to diverge already at 17.8 years before expected symptom onset. Lower BMI in preclinical MCs was significantly associated with less years before estimated symptom onset, higher global Aβ brain burden, and with lower delayed total recall scores in the logical memory test. The study provides cross-sectional evidence that weight loss starts one to two decades before expected symptom onset of ADAD. Our findings point toward a link between the pathophysiology of ADAD and disturbance of weight control mechanisms. Longitudinal follow-up studies are warranted to investigate BMI changes over time.

Regional cerebral metabolic alterations in dementia of the Alzheimer type: positron emission tomography with (/sup 18/F)fluorodeoxyglucose

DOE Office of Scientific and Technical Information (OSTI.GOV)

Friedland, R.P.; Budinger, T.F.; Ganz, E.

1983-08-01

Alzheimer disease is the most common cause of dementia in adults. Despite recent advances in our understanding of its anatomy and chemistry, we remain largely ignorant of its pathogenesis, physiology, diagnosis, and treatment. Dynamic positron emission tomography using (/sup 18/F)fluorodeoxyglucose (FDG) was performed on the Donner 280-crystal ring in 10 subjects with dementia of the Alzheimer type and six healthy age-matched controls. Ratios comparing mean counts per resolution element in frontal, temporoparietal, and entire cortex regions in brain sections 10 mm thick obtained 40-70 min following FDG injection showed relatively less FDG uptake in the temporoparietal cortex bilaterally in allmore » the Alzheimer subjects (p less than 0.01). Left-right alterations were less prominent than the anteroposterior changes. This diminished uptake was due to lowered rates of FDG use and suggests that the metabolic effects of Alzheimer disease are most concentrated in the temporoparietal cortex. Positron emission tomography is a most powerful tool for the noninvasive in vivo assessment of cerebral pathophysiology in dementia.« less

SPECT in Alzheimer`s disease and the dementias

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bonte, F.J.

1991-12-31

Among 90 patients with a clinical diagnosis of Alzheimer`s disease (AD), two subgroups were identified for special study, including 42 patients who had a history of dementia in one or more first-degree relatives, and 14 who had a diagnosis of early AD. Of the 42 patients with a family history of dementia, 34 out of the 35 patients whose final clinical diagnosis was possible or probable AD had positive SPECT rCBF studies. Studies in the 14 patients thought to have very early AD were positive in 11 cases. This finding suggests that altered cortical physiology, and hence, rCBF, occurs quitemore » early in the course of AD, perhaps before the onset of symptoms. It is possible that Xenon 133 rCBF studies might be used to detect the presence of subclinical AD in a population of individuals at risk to this disorder. Despite the drawbacks of a radionuclide with poor photon energy, Xenon 133, with its low cost and round-the-clock availability, deserves further study. Although the physical characteristics of Xenon 127 might make it preferable as a SPECT tracer, it is still not regularly available, and some instrument systems are not designed to handle its higher photon energies.« less

Ayurvedic medicinal plants for Alzheimer's disease: a review

PubMed Central

2012-01-01

Alzheimer's disease is an age-associated, irreversible, progressive neurodegenerative disease that is characterized by severe memory loss, unusual behavior, personality changes, and a decline in cognitive function. No cure for Alzheimer's exists, and the drugs currently available to treat the disease have limited effectiveness. It is believed that therapeutic intervention that could postpone the onset or progression of Alzheimer's disease would dramatically reduce the number of cases in the next 50 years. Ayurvedic medicinal plants have been the single most productive source of leads for the development of drugs, and over a hundred new products are already in clinical development. Indeed, several scientific studies have described the use of various Ayurvedic medicinal plants and their constituents for treatment of Alzheimer's disease. Although the exact mechanism of their action is still not clear, phytochemical studies of the different parts of the plants have shown the presence of many valuable compounds, such as lignans, flavonoids, tannins, polyphenols, triterpenes, sterols, and alkaloids, that show a wide spectrum of pharmacological activities, including anti-inflammatory, anti-amyloidogenic, anti-cholinesterase, hypolipidemic, and antioxidant effects. This review gathers research on various medicinal plants that have shown promise in reversing the Alzheimer's disease pathology. The report summarizes information concerning the phytochemistry, biological, and cellular activities and clinical applications of these various plants in order to provide sufficient baseline information that could be used in drug discovery campaigns and development process, thereby providing new functional leads for Alzheimer's disease. PMID:22747839

Left frontal hub connectivity delays cognitive impairment in autosomal-dominant and sporadic Alzheimer's disease.

PubMed

Franzmeier, Nicolai; Düzel, Emrah; Jessen, Frank; Buerger, Katharina; Levin, Johannes; Duering, Marco; Dichgans, Martin; Haass, Christian; Suárez-Calvet, Marc; Fagan, Anne M; Paumier, Katrina; Benzinger, Tammie; Masters, Colin L; Morris, John C; Perneczky, Robert; Janowitz, Daniel; Catak, Cihan; Wolfsgruber, Steffen; Wagner, Michael; Teipel, Stefan; Kilimann, Ingo; Ramirez, Alfredo; Rossor, Martin; Jucker, Mathias; Chhatwal, Jasmeer; Spottke, Annika; Boecker, Henning; Brosseron, Frederic; Falkai, Peter; Fliessbach, Klaus; Heneka, Michael T; Laske, Christoph; Nestor, Peter; Peters, Oliver; Fuentes, Manuel; Menne, Felix; Priller, Josef; Spruth, Eike J; Franke, Christiana; Schneider, Anja; Kofler, Barbara; Westerteicher, Christine; Speck, Oliver; Wiltfang, Jens; Bartels, Claudia; Araque Caballero, Miguel Ángel; Metzger, Coraline; Bittner, Daniel; Weiner, Michael; Lee, Jae-Hong; Salloway, Stephen; Danek, Adrian; Goate, Alison; Schofield, Peter R; Bateman, Randall J; Ewers, Michael

2018-04-01

Patients with Alzheimer's disease vary in their ability to sustain cognitive abilities in the presence of brain pathology. A major open question is which brain mechanisms may support higher reserve capacity, i.e. relatively high cognitive performance at a given level of Alzheimer's pathology. Higher functional MRI-assessed functional connectivity of a hub in the left frontal cortex is a core candidate brain mechanism underlying reserve as it is associated with education (i.e. a protective factor often associated with higher reserve) and attenuated cognitive impairment in prodromal Alzheimer's disease. However, no study has yet assessed whether such hub connectivity of the left frontal cortex supports reserve throughout the evolution of pathological brain changes in Alzheimer's disease, including the presymptomatic stage when cognitive decline is subtle. To address this research gap, we obtained cross-sectional resting state functional MRI in 74 participants with autosomal dominant Alzheimer's disease, 55 controls from the Dominantly Inherited Alzheimer's Network and 75 amyloid-positive elderly participants, as well as 41 amyloid-negative cognitively normal elderly subjects from the German Center of Neurodegenerative Diseases multicentre study on biomarkers in sporadic Alzheimer's disease. For each participant, global left frontal cortex connectivity was computed as the average resting state functional connectivity between the left frontal cortex (seed) and each voxel in the grey matter. As a marker of disease stage, we applied estimated years from symptom onset in autosomal dominantly inherited Alzheimer's disease and cerebrospinal fluid tau levels in sporadic Alzheimer's disease cases. In both autosomal dominant and sporadic Alzheimer's disease patients, higher levels of left frontal cortex connectivity were correlated with greater education. For autosomal dominant Alzheimer's disease, a significant left frontal cortex connectivity × estimated years of onset

Risk profiles of Alzheimer disease.

PubMed

Bilbul, Melanie; Schipper, Hyman M

2011-07-01

Alzheimer disease (AD) is a dementing, neurodegenerative disorder that affects approximately 500,000 Canadians and its prevalence is expected to double over the next 30 years. Although several medications may temporarily augment cognitive abilities in AD, there presently exists no proven method to avoid the inevitable clinical deterioration in this devastating condition. The delineation of risk factors for the development of AD offers hope for the advent of effective prevention or interventions that might retard the onset of symptoms. In this article, we provide a comprehensive review of midlife risk factors implicated in the etiopathogenesis of sporadic AD. Although some risk factors are heritable and largely beyond our control, others are determined by lifestyle or environment and are potentially modifiable. In a companion paper, we introduce the concept of an Alzheimer Risk Assessment Clinic for ascertainment and mitigation of these and other putative dementia risk factors in middle-aged adults.

Gender difference in apolipoprotein E-associated risk for familial Alzheimer disease: A possible clue to the higher incidence of Alzheimer disease in women

DOE Office of Scientific and Technical Information (OSTI.GOV)

Payami, H.; Zareparsi, S.; Montee, K.R.

1996-04-01

Late-onset Alzheimer disease (AD) is associated with the apolipoprotein E (APOE)-{epsilon}4 allele. In late-onset familial AD, women have a significantly higher risk of developing the disease than do men. The aim of this study was to determine whether the gender difference in familial AD is a function of APOE genotype. We studied 58 late-onset familial AD kindreds. Kaplan-Meier survival analysis was used to assess genotype-specific distributions of age at onset. Odds ratios were estimated by logistic regression with adjustment for age and by conditional logistic regression with stratification on families. All methods detected a significant gender difference for the {epsilon}4more » heterozygous genotype. In women, {epsilon}4 heterozygotes had higher risk than those without {epsilon}4; there was no significant difference between {epsilon}4 heterozygotes and {epsilon}4 homozygotes. In men, {epsilon}4 heterozygotes had lower risk than {epsilon}4 homozygotes; there was no significant difference between {epsilon}4 heterozygotes and those without {epsilon}4. A direct comparison of {epsilon}4 heterozygous men and women revealed a significant two-fold increased risk in women. We confirmed these results in 15 autopsy-confirmed AD kindreds from the National Cell Repository at Indiana University Alzheimer Disease Center. These observations are consistent with the increased incidence of familial AD in women and may be a critical clue to the role of gender in the pathogenesis of AD. 53 refs., 2 figs., 2 tabs.« less

Plasma amyloid beta-42 independently predicts both late-onset depression and Alzheimer disease.

PubMed

Blasko, Imrich; Kemmler, Georg; Jungwirth, Susanne; Wichart, Ildiko; Krampla, Wolfgang; Weissgram, Silvia; Jellinger, Kurt; Tragl, Karl Heinz; Fischer, Peter

2010-11-01

Depression in the elderly might represent a prodromal phase of Alzheimer disease (AD). High levels of plasma amyloid beta-42 (Aβ42) were found in prestages of AD and also in depressed patients in cross-sectional studies. This study examined the association of emerging late-onset depression (LOD) and AD with plasma Aβ42 in a sample of never depressed and not demented persons at baseline. Prospective 5-year longitudinal study. A community dwelling of older adults (N = 331) from the Vienna Transdanube Aging study. Laboratory measurements, cognitive functioning, and depressive symptoms were assessed at baseline, 2.5, and 5 years follow-ups. After exclusion of converters to AD, regression analysis revealed that higher plasma Aβ42 at baseline was a positive predictor for conversion to first episode of LOD. Independent of whether persons with mild cognitive impairment (MCI) at 2.5 years were included or excluded into regressions, higher plasma Aβ42 at baseline was a significant predictor for the development of probable or possible AD at 5 years. Higher conversion to AD was also associated with male gender but not with either higher scores on the Geriatric Depression Scale (GDS), with stroke or cerebral infarction nor apolipoprotein E ε4 allele. No association was found for an interaction between plasma Aβ42 levels and GDS. Higher plasma Aβ42 at baseline predicted the development of first episode of LOD and conversion to probable or possible AD. Emerging depression as measured by scores on GDS at the 2.5-year follow-up, either alone or as an interaction factor with plasma Aβ42, failed to predict the conversion to AD at 5 years.

Family History of Alzheimer's Disease and Cortical Thickness in Patients With Dementia.

PubMed

Ganske, Steffi; Haussmann, Robert; Gruschwitz, Antonia; Werner, Annett; Osterrath, Antje; Baumgaertel, Johanna; Lange, Jan; Donix, Katharina L; Linn, Jennifer; Donix, Markus

2016-08-01

A first-degree family history of Alzheimer's disease reflects genetic risks for the neurodegenerative disorder. Recent imaging data suggest localized effects of genetic risks on brain structure in healthy people. It is unknown whether this association can also be found in patients who already have dementia. Our aim was to investigate whether family history risk modulates regional medial temporal lobe cortical thickness in patients with Alzheimer's disease. We performed high-resolution magnetic resonance imaging and cortical unfolding data analysis on 54 patients and 53 nondemented individuals. A first-degree family history of Alzheimer's disease was associated with left hemispheric cortical thinning in the subiculum among patients and controls. The contribution of Alzheimer's disease family history to regional brain anatomy changes independent of cognitive impairment may reflect genetic risks that modulate onset and clinical course of the disease. © The Author(s) 2016.

Alzheimer disease: focus on computed tomography.

PubMed

Reynolds, April

2013-01-01

Alzheimer disease is the most common type of dementia, affecting approximately 5.3 million Americans. This debilitating disease is marked by memory loss, confusion, and loss of cognitive ability. The exact cause of Alzheimer disease is unknown although research suggests that it might result from a combination of factors. The hallmarks of Alzheimer disease are the presence of beta-amyloid plaques and neurofibrillary tangles in the brain. Radiologic imaging can help physicians detect these structural characteristics and monitor disease progression and brain function. Computed tomography and magnetic resonance imaging are considered first-line imaging modalities for the routine evaluation of Alzheimer disease.

Degree of Bilingualism Predicts Age of Diagnosis of Alzheimer's Disease in Low-Education but Not in Highly Educated Hispanics

ERIC Educational Resources Information Center

Gollan, Tamar H.; Salmon, David P.; Montoya, Rosa I.; Galasko, Douglas R.

2011-01-01

The current study investigated the relationship between bilingual language proficiency and onset of probable Alzheimer's disease (AD) in 44 Spanish-English bilinguals at the UCSD Alzheimer's Disease Research Center. Degree of bilingualism along a continuum was measured using Boston Naming Test (BNT) scores in each language. Higher degrees of…

Correlates and prevalence of hypogonadism in patients with early- and late-onset type 2 diabetes.

PubMed

Li, Y; Zhang, M; Liu, X; Cui, W; Rampersad, S; Li, F; Lin, Z; Yang, P; Li, H; Sheng, C; Cheng, X; Qu, S

2017-07-01

This study aims to compare the prevalence of hypogonadism between male patients with early-onset type 2 diabetes mellitus (T2DM) and late-onset type 2 diabetes. A total of 122 male patients with early-onset T2DM (diagnosis age ≤40 years) and 100 male patients with late-onset T2DM (diagnosis age >40 years) were recruited from our in-patient department between 1 January 2013 and 28 December 2015. Serum FSH, LH, testosterone, lipid profile, uric acid, HbA1c, and beta-cell function were determined in blood samples. The diagnosis of hypogonadism was based on the levels of LH, FSH, and total testosterone. The mean onset age was 29.86 ± 6.31 and 54.47 ± 9.97 years old in the early-onset group and late-onset group, respectively. Compared with late-onset T2DM, those with early-onset T2DM had a higher proportion of new-onset diabetes, were more likely to be obese, and had worse glycemic control, lipid control, and lower sex hormone-binding globulin (SHBG). The prevalence of hypogonadism was much higher in the early-onset group than in the late-onset group (48.0% vs. 26.7%, p < 0.05). The rate of secondary hypogonadism in the early-onset group and late-onset group were 44.3% and 25.0%, respectively (p < 0.05). Obesity, waist circumference, and SHBG were significantly associated with serum total testosterone level in all, early-onset, and late-onset T2DM. Both all and early-onset T2DM groups had positive correlations between total testosterone and fasting C-peptide, total cholesterol, triglycerides, and uric acid. Our results indicate that in a population of admission to a large urban hospital in China, the prevalence of hypogonadism was higher in the patients with early-onset T2DM than that of late-onset T2DM. This prevalence might be attributable to greater obesity, worse lipid control, and lower SHBG levels in those patients. © 2017 American Society of Andrology and European Academy of Andrology.

Late-onset Becker-type muscular dystrophy in a Border terrier dog.

PubMed

Jeandel, A; Garosi, L S; Davies, L; Guo, L T; Salgüero, R; Shelton, G D

2018-01-29

A 9-year-old Border terrier was presented to a referral hospital after a 1-year history of progressive stiffness and exercise intolerance. Neurological examination was consistent with a neuromuscular disorder. Serum creatine kinase activity was mildly elevated. A myopathy was suspected based on MRI findings and electrophysiological examination. Muscle histopathology was consistent with a severe non-inflammatory myopathy of a dystrophic type. Immunofluorescence and western blotting confirmed a dystrophinopathy with an 80-kDa truncated dystrophin fragment similar to Becker muscular dystrophy in people. To our knowledge, this is the first description of a late-onset Becker-type muscular dystrophy in a dog, and the first description of a dystrophinopathy in a Border terrier. Muscular dystrophy in dogs should not be ruled out based on late onset clinical signs and only mildly elevated creatine kinase. © 2018 British Small Animal Veterinary Association.

Examination of blood-brain barrier permeability in dementia of the Alzheimer type with (68Ga)EDTA and positron emission tomography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schlageter, N.L.; Carson, R.E.; Rapoport, S.I.

1987-02-01

Positron emission tomography with (/sup 68/Ga)ethylenediaminetetraacetic acid ((/sup 68/Ga)EDTA) was used to examine the integrity of the blood-brain barrier (BBB) in five patients with dementia of the Alzheimer type and in five healthy age-matched controls. Within a scanning time of 90 min, there was no evidence that measurable intravascular tracer entered the brain in either the dementia or the control group. An upper limit for the cerebrovascular permeability-surface area product of (68Ga)EDTA was estimated as 2 X 10(-6) s-1 in both groups. The results provide no evidence for breakdown of the BBB in patients with dementia of the Alzheimer type.

Aluminium in brain tissue in familial Alzheimer's disease.

PubMed

Mirza, Ambreen; King, Andrew; Troakes, Claire; Exley, Christopher

2017-03-01

The genetic predispositions which describe a diagnosis of familial Alzheimer's disease can be considered as cornerstones of the amyloid cascade hypothesis. Essentially they place the expression and metabolism of the amyloid precursor protein as the main tenet of disease aetiology. However, we do not know the cause of Alzheimer's disease and environmental factors may yet be shown to contribute towards its onset and progression. One such environmental factor is human exposure to aluminium and aluminium has been shown to be present in brain tissue in sporadic Alzheimer's disease. We have made the first ever measurements of aluminium in brain tissue from 12 donors diagnosed with familial Alzheimer's disease. The concentrations of aluminium were extremely high, for example, there were values in excess of 10μg/g tissue dry wt. in 5 of the 12 individuals. Overall, the concentrations were higher than all previous measurements of brain aluminium except cases of known aluminium-induced encephalopathy. We have supported our quantitative analyses using a novel method of aluminium-selective fluorescence microscopy to visualise aluminium in all lobes of every brain investigated. The unique quantitative data and the stunning images of aluminium in familial Alzheimer's disease brain tissue raise the spectre of aluminium's role in this devastating disease. Copyright © 2016 The Authors. Published by Elsevier GmbH.. All rights reserved.

Can Better Management of Periodontal Disease Delay the Onset and Progression of Alzheimer's Disease?

PubMed

Harding, Alice; Robinson, Sarita; Crean, StJohn; Singhrao, Sim K

2017-01-01

A risk factor relationship exists between periodontal disease and Alzheimer's disease (AD) via tooth loss, and improved memory following dental intervention. This links the microbial contribution from indigenous oral periodontal pathogens to the manifestation of chronic conditions, such as AD. Here, we use Porphyromonas gingivalis infection to illustrate its effect on mental health. P. gingivalis infection, in its primary sub-gingival niche, can cause polymicrobial synergy and dysbiosis. Dysbiosis describes the residency of select commensals from the oral cavity following co-aggregation around the dominant keystone pathogen, such as P. gingivalis, to gain greater virulence. The initial process involves P. gingivalis disturbing neutrophil mediated innate immune responses in the healthy gingivae and then downregulating adaptive immune cell differentiation and development to invade, and subsequently, establish new dysbiotic bacterial communities. Immune responses affect the host in general and functionally via dietary adjustments caused by tooth loss. Studies from animals orally infected with P. gingivalis confirm this bacterium can transmigrate to distant organ sites (the brain) and contribute toward peripheral and intracerebral inflammation, and compromise vascular and microvascular integrity. In another study, P. gingivalis infection caused sleep pattern disturbances by altering glial cell light/dark molecular clock activity, and this, in turn, can affect the clearance of danger associated molecular patterns, such as amyloid-β, via the glymphatic system. Since P. gingivalis can transmigrate to the brain and modulate organ-specific inflammatory innate and adaptive immune responses, this paper explores whether better management of indigenous periodontal bacteria could delay/prevent the onset and/or progression of dementia.

Support for an hypothesis linking Alzheimer`s disease and Down syndrome

DOE Office of Scientific and Technical Information (OSTI.GOV)

Geller, L.N.; Benjamin, M.B.; Dressler, D.

1994-09-01

A connection between Alzheimer`s disease (AD) and Down syndrome (trisomy 21) is indicated by the fact that Down syndrome individuals develop AD neuropathology by the third or fourth decade of life. One explanation for the connection between AD and Down syndrome would be that the overexpression of a gene or genes on chromosome 21 results in Alzheimer`s disease, the most likely candidate being the amyloid precursor protein (APP) gene. However, mutations in the APP gene have been found to be associated with only a very small percentage of familial AD cases. An alternative cause of some Alzheimer`s disease cases maymore » be sporadic trisomy of chromosome 21, resulting from mutations or toxins that cause chromosome nondisjunction. Several predictions can be made based on this hypothesis. One prediction is that there should be more trisomy 21 in cells from AD individuals than from unaffected controls. Using quantitative fluorescence in situ hybridization to compare the number of trisomy chromosome 21 cells in cultured fibroblasts from AD and unaffected individuals, we have shown that there are a significantly larger number of trisomy 21 cells from AD individuals. Another prediction is that a defect in the mitotic spindle apparatus could be the underlying cause of the aneuploidy. Cultured lymphoblasts from AD and unaffected individuals were briefly exposed to the microtubule-disrupting agent colchicine. As assayed by the subsequent appearance of metaphase chromosomes showing centromere separation, cells from AD patients were significantly more sensitive to colchicine treatment compared to cells from unaffected individuals, supporting the prediction of an altered spindle apparatus. Finally, we would predict that both types of patients should share some physical symptoms. We have also found that AD, like Down`s patients, are hypersensitive to the effect of the cholinergic antagonist, tropicamide, on pupil dilation, which may serve as a diagnostic test for Alzheimer`s

Germinal centre frequency is decreased in pancreatic lymph nodes from individuals with recent-onset type 1 diabetes.

PubMed

Willcox, Abby; Richardson, Sarah J; Walker, Lucy S K; Kent, Sally C; Morgan, Noel G; Gillespie, Kathleen M

2017-07-01

Pancreatic lymph nodes (PLNs) are critical sites for the initial interaction between islet autoantigens and autoreactive lymphocytes, but the histology of PLNs in tissue from individuals with type 1 diabetes has not been analysed in detail. The aim of this study was to examine PLN tissue sections from healthy donors compared with those at risk of, or with recent-onset and longer-duration type 1 diabetes. Immunofluorescence staining was used to examine PLN sections from the following donor groups: non-diabetic (n=15), non-diabetic islet autoantibody-positive (n=5), recent-onset (≤1.5 years duration) type 1 diabetes (n=13), and longer-duration type 1 diabetes (n=15). Staining for CD3, CD20 and Ki67 was used to detect primary and secondary (germinal centre-containing) follicles and CD21 and CD35 to detect follicular dendritic cell networks. The frequency of secondary follicles was lower in the recent-onset type 1 diabetes group compared with the non-diabetic control group. The presence of insulitis (as evidence of ongoing beta cell destruction) and diagnosis of type 1 diabetes at a younger age, however, did not appear to be associated with a lower frequency of secondary follicles. A higher proportion of primary B cell follicles were observed to lack follicular dendritic cell networks in the recent-onset type 1 diabetes group. Histological analysis of rare PLNs from individuals with type 1 diabetes suggests a previously unrecognised phenotype comprising decreased primary B cell follicle frequency and fewer follicular dendritic cell networks in recent-onset type 1 diabetes.

Type 3 Diabetes Mellitus: A Novel Implication of Alzheimers Disease.

PubMed

Leszek, Jerzy; Trypka, Elzbieta; Tarasov, Vadim V; Ashraf, Ghulam Md; Aliev, Gjumrakch

2017-01-01

The brain of patients with Alzheimer disease (AD) showed the evidence of reduced expression of insulin and neuronal insulin receptors, as compared with those of age-matched controls. This event gradually and certainly leads to a breakdown of the entire insulin-signaling pathway, which manifests insulin resistance. This in turn affects brain metabolism and cognitive functions, which are the bestdocumented abnormalities in AD. These observations led Dr. de la Monte and her colleagues to suggest that AD is actually a neuroendocrine disorder that resembles type 2 diabetes mellitus. The truth would be more complex with understanding the role of low-density lipoprotein receptor-related protein 1, Aβ derived diffusible ligands, and advanced glycation end products. However, now it known as "brain diabetes" and is called type 3 diabetes mellitus (T3DM). This review provides an overview of "brain diabetes" focusing on the reason why the phenomenon is called T3DM. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Saitohin Q7R polymorphism is associated with late-onset Alzheimer's disease susceptibility among caucasian populations: a meta-analysis.

PubMed

Huang, Rong; Tian, Sai; Cai, Rongrong; Sun, Jie; Xia, Wenqing; Dong, Xue; Shen, Yanjue; Wang, Shaohua

2017-08-01

Saitohin (STH) Q7R polymorphism has been reported to influence the individual's susceptibility to Alzheimer's disease (AD); however, conclusions remain controversial. Therefore, we performed this meta-analysis to explore the association between STH Q7R polymorphism and AD risk. Systematic literature searches were performed in the PubMed, Embase, Cochrane Library and Web of Science for studies published before 31 August 2016. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the strength of the association using a fixed- or random-effects model. Subgroup analyses, Galbraith plot and sensitivity analyses were also performed. All statistical analyses were performed with STATA Version 12.0. A total of 19 case-control studies from 17 publications with 4387 cases and 3972 controls were included in our meta-analysis. The results showed that the Q7R polymorphism was significantly associated with an increased risk of AD in a recessive model (RR versus QQ+QR, OR = 1.27, 95% CI = 1.01-1.60, P = 0.040). After excluding the four studies not carried out in caucasians, the overall association was unchanged in all comparison models. Further subgroup analyses stratified by the time of AD onset, and the quality of included studies provided statistical evidence of significant increased risk of AD in RR versus QQ+QR model only in late-onset subjects (OR = 1.56, 95% CI = 1.07-2.26, P = 0.021) and in studies with high quality (OR = 1.37, 95% CI = 1.01-1.86, P = 0.043). This meta-analysis suggests that the RR genotype in saitohin Q7R polymorphism may be a human-specific risk factor for AD, especially among late-onset AD subjects and caucasian populations. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Evaluation of Gene-Based Family-Based Methods to Detect Novel Genes Associated With Familial Late Onset Alzheimer Disease

PubMed Central

Fernández, Maria V.; Budde, John; Del-Aguila, Jorge L.; Ibañez, Laura; Deming, Yuetiva; Harari, Oscar; Norton, Joanne; Morris, John C.; Goate, Alison M.; Cruchaga, Carlos

2018-01-01

Gene-based tests to study the combined effect of rare variants on a particular phenotype have been widely developed for case-control studies, but their evolution and adaptation for family-based studies, especially studies of complex incomplete families, has been slower. In this study, we have performed a practical examination of all the latest gene-based methods available for family-based study designs using both simulated and real datasets. We examined the performance of several collapsing, variance-component, and transmission disequilibrium tests across eight different software packages and 22 models utilizing a cohort of 285 families (N = 1,235) with late-onset Alzheimer disease (LOAD). After a thorough examination of each of these tests, we propose a methodological approach to identify, with high confidence, genes associated with the tested phenotype and we provide recommendations to select the best software and model for family-based gene-based analyses. Additionally, in our dataset, we identified PTK2B, a GWAS candidate gene for sporadic AD, along with six novel genes (CHRD, CLCN2, HDLBP, CPAMD8, NLRP9, and MAS1L) as candidate genes for familial LOAD. PMID:29670507

Evaluation of Gene-Based Family-Based Methods to Detect Novel Genes Associated With Familial Late Onset Alzheimer Disease.

PubMed

Fernández, Maria V; Budde, John; Del-Aguila, Jorge L; Ibañez, Laura; Deming, Yuetiva; Harari, Oscar; Norton, Joanne; Morris, John C; Goate, Alison M; Cruchaga, Carlos

2018-01-01

Gene-based tests to study the combined effect of rare variants on a particular phenotype have been widely developed for case-control studies, but their evolution and adaptation for family-based studies, especially studies of complex incomplete families, has been slower. In this study, we have performed a practical examination of all the latest gene-based methods available for family-based study designs using both simulated and real datasets. We examined the performance of several collapsing, variance-component, and transmission disequilibrium tests across eight different software packages and 22 models utilizing a cohort of 285 families ( N = 1,235) with late-onset Alzheimer disease (LOAD). After a thorough examination of each of these tests, we propose a methodological approach to identify, with high confidence, genes associated with the tested phenotype and we provide recommendations to select the best software and model for family-based gene-based analyses. Additionally, in our dataset, we identified PTK2B , a GWAS candidate gene for sporadic AD, along with six novel genes ( CHRD, CLCN2, HDLBP, CPAMD8, NLRP9 , and MAS1L ) as candidate genes for familial LOAD.

Gene expression levels as endophenotypes in genome-wide association studies of Alzheimer disease

PubMed Central

Zou, F.; Carrasquillo, M. M.; Pankratz, V. S.; Belbin, O.; Morgan, K.; Allen, M.; Wilcox, S. L.; Ma, L.; Walker, L. P.; Kouri, N.; Burgess, J. D.; Younkin, L. H.; Younkin, Samuel G.; Younkin, C. S.; Bisceglio, G. D.; Crook, J. E.; Dickson, D. W.; Petersen, R. C.; Graff-Radford, N.; Younkin, Steven G.; Ertekin-Taner, N.

2010-01-01

Background: Late-onset Alzheimer disease (LOAD) is a common disorder with a substantial genetic component. We postulate that many disease susceptibility variants act by altering gene expression levels. Methods: We measured messenger RNA (mRNA) expression levels of 12 LOAD candidate genes in the cerebella of 200 subjects with LOAD. Using the genotypes from our LOAD genome-wide association study for the cis-single nucleotide polymorphisms (SNPs) (n = 619) of these 12 LOAD candidate genes, we tested for associations with expression levels as endophenotypes. The strongest expression cis-SNP was tested for AD association in 7 independent case-control series (2,280 AD and 2,396 controls). Results: We identified 3 SNPs that associated significantly with IDE (insulin degrading enzyme) expression levels. A single copy of the minor allele for each significant SNP was associated with ∼twofold higher IDE expression levels. The most significant SNP, rs7910977, is 4.2 kb beyond the 3′ end of IDE. The association observed with this SNP was significant even at the genome-wide level (p = 2.7 × 10−8). Furthermore, the minor allele of rs7910977 associated significantly (p = 0.0046) with reduced LOAD risk (OR = 0.81 with a 95% CI of 0.70-0.94), as expected biologically from its association with elevated IDE expression. Conclusions: These results provide strong evidence that IDE is a late-onset Alzheimer disease (LOAD) gene with variants that modify risk of LOAD by influencing IDE expression. They also suggest that the use of expression levels as endophenotypes in genome-wide association studies may provide a powerful approach for the identification of disease susceptibility alleles. GLOSSARY AD = Alzheimer disease; CI = confidence interval; GWAS = genome-wide association study; LOAD = late-onset Alzheimer disease; mRNA = messenger RNA; OR = odds ratio; SNP = single nucleotide polymorphism. PMID:20142614

Cognitive decline in patients with Alzheimer's disease, vascular dementia and senile dementia of Lewy body type.

PubMed

Ballard, C; Patel, A; Oyebode, F; Wilcock, G

1996-05-01

One hundred and twenty-four patients with DSM-III-R dementia were assessed with a standardized battery which included the Geriatric Mental State Schedule, the History and Aetiology Schedule, the Secondary Dementia Schedule and the CAMCOG. Patients with Alzheimer's disease, vascular dementia and senile dementia of Lewy body type (SDLT) all had a similar degree of cognitive impairment at the time of the baseline interview. Patients with Alzheimer's disease and vascular dementia each experienced a mean decline of 27 points in patients with SDLT. Patients with SDLT had a significantly greater decline of verbal fluency than both the other groups. Women were significantly more impaired than men at the time of the baseline assessment but experienced a similar decline during the year of follow-up.

Cholinergic nicotinic and muscarinic receptors in dementia of Alzheimer, Parkinson and Lewy body types.

PubMed

Perry, E K; Smith, C J; Court, J A; Perry, R H

1990-01-01

Cholinergic nicotinic and muscarinic receptor binding were measured in post mortem human brain tissue, using low (nM) concentrations of (3H)-nicotine to detect predominately the high affinity nicotinic site and (3H)-N-methylscopolamine in the presence and absence of 3 x 10(-4) M carbachol to measure both the low and high affinity agonist subtypes of the muscarinic receptor group. Consistent with most previous reports, the nicotinic but not muscarinic binding was reduced in the different forms of dementia associated with cortical cholinergic deficits, including Alzheimer's and Parkinson's disease, senile dementia of Lewy body type (SDLT) and Down's syndrome (over 50 years). Analysis of (3H)-nicotine binding displaced by a range of carbachol concentrations (10(-9)-10(-3) M) indicated 2 binding sites for nicotine and that the high affinity rather than low affinity site was reduced in Alzheimer's disease. In all 3 cortical areas investigated (temporal, parietal and occipital) there were increases in the low affinity muscarinic site in Parkinson's disease and SDLT but not Alzheimer's disease or middle-aged Down's syndrome. This observation raised the question of whether the presence of neurofibrillary tangles (evident in the latter but not former 2 disorders) is incompatible with denervation-induced muscarinic supersensitivity in cholinoceptive neurons which include cortical pyramids generally affeted by tangle formation.

Predictability and Risk Factors for Development of New-Onset Type 2 Diabetes Mellitus After Transplant in the Saudi Population.

PubMed

Alshamsi, Shaikha; Basri, Nawal; Flaiw, Ahmed; Ghamdi, Ghormullah; Hejaili, Fayez; Shaheen, Faissal A M; Sheayria, Foud; Jaradat, Maha; Al Sayyari, Abdulla

2016-06-01

The study objective was to investigate the predictability and risk factors for the development of new-onset type 2 diabetes mellitus after transplant in the Saudi population. This was a retrospective observational cohort study in adult kidney transplant recipients who developed new-onset type 2 diabetes mellitus after transplant. Patients with and without new-onset type 2 diabetes mellitus after transplant were compared for demographic factors, blood glucose levels at 4-hour intervals for 24 hours after transplant, and serum creatinine levels at 6 and 12 months after transplant. Of 279 patients included in our study, 15.5% developed new-onset type 2 diabetes mellitus after a mean follow-up of 4.6 ± 2.1 years after transplant. Patients with new-onset type 2 diabetes mellitus after transplant were significant older (P = .001), had a higher body mass index (P = .001), and had higher fasting blood glucose levels 24 hours after transplant (P = .03). No significant differences were observed regarding sex, transplant type, or serum creatinine levels at 6 and 12 months. Risk factors for new-onset type 2 diabetes mellitus after transplant are body mass index (P = .001; relative risk of 1.26), fasting blood glucose at 24 hours (P = .001; relative risk of 1.3), age (P = .001; relative risk of 1.44), and family history of diabetes mellitus (P = .001; relative risk of 31.3). Risk factors for developing new-onset type 2 diabetes mellitus were age, heavier weight, body mass index, family history of diabetes mellitus, and having higher fasting blood glucose levels 24 hours after transplant, with family history of diabetes mellitus being an especially very high significant risk factor.

Alzheimer's Disease and Type 2 Diabetes: A Critical Assessment of the Shared Pathological Traits

PubMed Central

Chatterjee, Shreyasi; Mudher, Amritpal

2018-01-01

Alzheimer's disease (AD) and Type 2 Diabetes Mellitus (T2DM) are two of the most prevalent diseases in the elderly population worldwide. A growing body of epidemiological studies suggest that people with T2DM are at a higher risk of developing AD. Likewise, AD brains are less capable of glucose uptake from the surroundings resembling a condition of brain insulin resistance. Pathologically AD is characterized by extracellular plaques of Aβ and intracellular neurofibrillary tangles of hyperphosphorylated tau. T2DM, on the other hand is a metabolic disorder characterized by hyperglycemia and insulin resistance. In this review we have discussed how Insulin resistance in T2DM directly exacerbates Aβ and tau pathologies and elucidated the pathophysiological traits of synaptic dysfunction, inflammation, and autophagic impairments that are common to both diseases and indirectly impact Aβ and tau functions in the neurons. Elucidation of the underlying pathways that connect these two diseases will be immensely valuable for designing novel drug targets for Alzheimer's disease. PMID:29950970

CAP--advancing the evaluation of preclinical Alzheimer disease treatments.

PubMed

Reiman, Eric M; Langbaum, Jessica B; Tariot, Pierre N; Lopera, Francisco; Bateman, Randall J; Morris, John C; Sperling, Reisa A; Aisen, Paul S; Roses, Allen D; Welsh-Bohmer, Kathleen A; Carrillo, Maria C; Weninger, Stacie

2016-01-01

If we are to find treatments to postpone, reduce the risk of, or completely prevent the clinical onset of Alzheimer disease (AD), we need faster methods to evaluate promising preclinical AD treatments, new ways to work together in support of common goals, and a determination to expedite the initiation and performance of preclinical AD trials. In this article, we note some of the current challenges, opportunities and emerging strategies in preclinical AD treatment. We describe the Collaboration for Alzheimer's Prevention (CAP)-a convening, harmonizing and consensus-building initiative to help stakeholders advance AD prevention research with rigour, care and maximal impact-and we demonstrate the impact of CAP on the goals and design of new preclinical AD trials.

Inhalational Alzheimer's disease: an unrecognized—and treatable—epidemic

PubMed Central

Bredesen, Dale E.

2016-01-01

Alzheimer's disease is one of the most significant healthcare problems today, with a dire need for effective treatment. Identifying subtypes of Alzheimer's disease may aid in the development of therapeutics, and recently three different subtypes have been described: type 1 (inflammatory), type 2 (non-inflammatory or atrophic), and type 3 (cortical). Here I report that type 3 Alzheimer's disease is the result of exposure to specific toxins, and is most commonly inhalational (IAD), a phenotypic manifestation of chronic inflammatory response syndrome (CIRS), due to biotoxins such as mycotoxins. The appropriate recognition of IAD as a potentially important pathogenetic condition in patients with cognitive decline offers the opportunity for successful treatment of a large number of patients whose current prognoses, in the absence of accurate diagnosis, are grave. PMID:26870879

Postural set for balance control is normal in Alzheimer's but not in Parkinson's disease.

PubMed

Chong, R K; Jones, C L; Horak, F B

1999-03-01

It has been suggested that patients with dementia of the Alzheimer type have abnormalities in the basal ganglia, and thus, may have similar sensorimotor problems as patients with basal ganglia degeneration from Parkinson's disease. Whether the similarity extends to balance control is unknown. One distinguishing feature of balance disorder in Parkinson's disease is difficulty with changing postural set in terms of adapting the amplitude of leg muscle activity as a function of support condition. We, therefore, tested whether patients with Alzheimer's disease without extrapyramidal signs would show a similar problem in changing postural set as patients with Parkinson's disease. The ability to quickly change postural set was measured by comparing leg muscle activity under two conditions of support (free stance, versus grasping a frame, or sitting) during backward surface translations, during toes up surface rotations, and during voluntary rise to toes. Results were compared among 12 healthy adults, 8 nondemented Parkinson's patients on their usual dose of medication, and 11 Alzheimer patients without extrapyramidal signs. Subjects with Alzheimer's, but not Parkinson's, disease performed similarly to the healthy control subjects. They changed postural set immediately, by suppressing leg muscle activity to low levels when supported. Parkinson subjects did not change postural set immediately. They did not suppress the tibialis anterior in voluntary rise to toes when holding, nor the soleus in perturbed sitting as much as the healthy control and Alzheimer subjects in the first trial. Instead, the Parkinson subjects changed set more slowly, over repeated and consecutive trials in both protocols. The onset latencies of soleus responses to backward surface translations and perturbed sitting, as well as tibialis anterior responses to toes up rotations, were the same for all three groups. Alzheimer patients without extrapyramidal signs, unlike nondemented Parkinson's disease

Somatotype in Alzheimer's disease.

PubMed

Buffa, Roberto; Lodde, Marco; Floris, Giovanni; Zaru, Cristina; Putzu, Paolo F; Marini, Elisabetta

2007-01-01

The clinical picture of Alzheimer's disease includes anthropometric and body composition variations. Somatotyping is a practical non-invasive method to assess body type. The objective of this study was to describe the somatotype of a sample of Alzheimer's patients. The sample consisted of 55 Alzheimer disease individuals in the mild-moderate stage (17 men, mean age = 76.9 +/- 7.2 years; 38 women, mean age = 79.6 +/- 6.4 years). The pathological subjects were compared with a control group consisting of 280 healthy individuals (134 men, mean age = 74.2 +/- 7.3 years; 146 women, mean age = 74.9 +/- 7.4 years). The Heath-Carter somatotype was applied. The Alzheimer patients (mean somatotype: 6.1-5.5-0.8 in men, 7.0-5.3-0.7 in women) are less mesomorphic and more ectomorphic than the controls (mean somatotype: 6.1-6.3-0.6 in men, 7.7-6.3-0.4 in women), the differences being significant in women (mesomorphy, p = 0.000; ectomorphy, p = 0.012). Alzheimer patients show peculiar somatometric characteristics. The somatotype technique could represent a suitable tool for the study and monitoring of physical variations. Copyright 2007 S. Karger AG, Basel.

Alzheimer - resources

MedlinePlus

Resources - Alzheimer ... The following organizations are good resources for information on Alzheimer disease : Alzheimer's Association -- www.alz.org National Institute on Aging -- www.nia.nih.gov/health/alzheimers Alzheimers. ...

Is α‐T catenin (VR22) an Alzheimer's disease risk gene?

PubMed Central

Bertram, Lars; Mullin, Kristina; Parkinson, Michele; Hsiao, Monica; Moscarillo, Thomas J; Wagner, Steven L; Becker, K David; Velicelebi, Gonul; Blacker, Deborah; Tanzi, Rudolph E

2007-01-01

Background Recently, conflicting reports have been published on the potential role of genetic variants in the α‐T catenin gene (VR22; CTNNA3) on the risk for Alzheimer's disease. In these papers, evidence for association is mostly observed in multiplex families with Alzheimer's disease, whereas case–control samples of sporadic Alzheimer's disease are predominantly negative. Methods After sequencing VR22 in multiplex families with Alzheimer's disease linked to chromosome 10q21, we identified a novel non‐synonymous (Ser596Asn; rs4548513) single nucleotide polymorphism (SNP). This and four non‐coding SNPs were assessed in two independent samples of families with Alzheimer's disease, one with 1439 subjects from 437 multiplex families with Alzheimer's disease and the other with 489 subjects from 217 discordant sibships. Results A weak association with the Ser596Asn SNP in the multiplex sample, predominantly in families with late‐onset Alzheimer's disease (p = 0.02), was observed. However, this association does not seem to contribute substantially to the chromosome 10 Alzheimer's disease linkage signal that we and others have reported previously. No evidence was found of association with any of the four additional SNPs tested in the multiplex families with Alzheimer's disease. Finally, the Ser596Asn change was not associated with the risk for Alzheimer's disease in the independent discordant sibship sample. Conclusions This is the first study to report evidence of an association between a potentially functional, non‐synonymous SNP in VR22 and the risk for Alzheimer's disease. As the underlying effects are probably small, and are only seen in families with multiple affected members, the population‐wide significance of this finding remains to be determined. PMID:17209133

Taste detection and recognition thresholds in Japanese patients with Alzheimer-type dementia.

PubMed

Ogawa, Takao; Irikawa, Naoya; Yanagisawa, Daijiro; Shiino, Akihiko; Tooyama, Ikuo; Shimizu, Takeshi

2017-04-01

Alzheimer-type dementia (AD) is pathologically characterized by massive neuronal loss in the brain, and the taste cortex is thought to be affected. However, there are only a few reports regarding the gustatory function of AD patients, and the conclusions of this research are inconsistent. This prospective study enrolled 22 consecutive patients with mild to moderately severe Alzheimer-type dementia (AD) with mean age of 84.0 years, and 49 elderly volunteers without dementia with mean age of 71.0 years as control subjects. The control subjects were divided into two groups according to age: a younger group (N=28, mean age: 68.5) and an older group (N=21, mean age: 83.0). The gustatory function was investigated using the filter paper disc method (FPD) and electrogustometry (EGM). The gustatory function as measured by the FPD was significantly impaired in patients with AD as compared with age-matched control subjects; no such difference was found between the younger and the older control groups. On the other hand, as for the EGM thresholds, there were no differences between the AD patient group and the age-matched controls. The FPD method demonstrated decreased gustatory function in AD patients beyond that of aging. On the other hand, EGM thresholds did not differ between the AD patient group and the age-matched controls. These results suggest that failure of taste processing in the brain, but not taste transmission in the peripheral taste system, occurs in patients with AD. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Patterns, evolution, and severity of striatal injury in insidious- versus acute-onset glutaric aciduria type 1.

PubMed

Boy, Nikolas; Garbade, Sven F; Heringer, Jana; Seitz, Angelika; Kölker, Stefan; Harting, Inga

2018-05-02

Striatal injury in patients with glutaric aciduria type 1 (GA1) results in a complex, predominantly dystonic, movement disorder. Onset may be acute following acute encephalopathic crisis (AEC) or insidious without apparent acute event. We analyzed clinical and striatal magnetic resonance imaging (MRI) findings in 21 symptomatic GA1 patients to investigate if insidious- and acute-onset patients differed in timing, pattern of striatal injury, and outcome. Eleven patients had acute and ten had insidious onset, two with later AEC (acute-on-insidious). The median onset of dystonia was 10 months in both groups, and severity was greater in patients after AEC (n = 8 severe, n = 5 moderate) than in insidious onset (n = 4 mild, n = 3 moderate, n = 1 severe). Deviations from guideline-recommended basic metabolic treatment were identified in six insidious-onset patients. Striatal lesions were extensive in all acute-onset patients and restricted to the dorsolateral putamen in eight of ten insidious-onset patients. After AEC, the two acute-on-insidious patients had extensive striatal changes superimposed on pre-existing dorsolateral putaminal lesions. Two insidious-onset patients with progressive dystonia without overt AEC also had extensive striatal changes, one with sequential striatal injury revealed by diffusion-weighted imaging. Insidious-onset patients had a latency phase of 3.5 months to 6.5 years between detection and clinical manifestation of dorsolateral putaminal lesions. Insidious-onset type GA1 is characterized by dorsolateral putaminal lesions, less severe dystonia, and an asymptomatic latency phase, despite already existing lesions. Initially normal MRI during the first months and deviations from guideline-recommended treatment in a large proportion of insidious-onset patients substantiate the protective effect of neonatally initiated treatment.

Association of traumatic brain injury and Alzheimer disease onset: A systematic review.

PubMed

Julien, J; Joubert, S; Ferland, M-C; Frenette, L C; Boudreau-Duhaime, M M; Malo-Véronneau, L; de Guise, E

2017-09-01

Inconsistencies regarding the risk of developing Alzheimer disease after traumatic brain injury (TBI) remain in the literature. Indeed, why AD develops in certain TBI patients while others are unaffected is still unclear. The aim of this study was to performed a systematic review to investigate whether certain variables related to TBI, such as TBI severity, loss of consciousness (LOC) and post-traumatic amnesia (PTA), are predictors of risk of AD in adults. From 841 citations retrieved from MEDLINE via PubMed, EMBASE, PSYINFO and Cochrane Library databases, 18 studies were eligible for the review. The review revealed that about 55.5% of TBI patients may show deteriorated condition, from acute post-TBI cognitive deficits to then meeting diagnostic criteria for AD, but whether TBI is a risk factor for AD remains elusive. Failure to establish such a link may be related to methodological problems in the studies. To shed light on this dilemma, future studies should use a prospective design, define the types and severities of TBI and use standardized AD and TBI diagnostic criteria. Ultimately, an AD prediction model, based on several variables, would be useful for clinicians detecting TBI patients at risk of AD. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

A transgenic Alzheimer rat with plaques, tau pathology, behavioral impairment, oligomeric Aβ and frank neuronal loss

PubMed Central

Cohen, Robert M.; Rezai-Zadeh, Kavon; Weitz, Tara M.; Rentsendorj, Altan; Gate, David; Spivak, Inna; Bholat, Yasmin; Vasilevko, Vitaly; Glabe, Charles G.; Breunig, Joshua J.; Rakic, Pasko; Davtyan, Hayk; Agadjanyan, Michael G.; Kepe, Vladimir; Barrio, Jorge; Bannykh, Serguei; Szekely, Christine A.; Pechnick, Robert N.; Town, Terrence

2013-01-01

Alzheimer’s disease (AD) is hallmarked by amyloid plaques, neurofibrillary tangles, and widespread cortical neuronal loss (Selkoe, 2001). The ‘amyloid cascade hypothesis’ posits that cerebral amyloid sets neurotoxic events into motion that precipitate Alzheimer dementia (Hardy and Allsop, 1991). Yet, faithful recapitulation of all AD features in widely used transgenic (Tg) mice engineered to overproduce Aβ peptides has been elusive. We have developed a Tg rat model (line TgF344-AD) expressing mutant human amyloid precursor protein (APPsw) and presenilin 1 (PS1ΔE9) genes, each independent causes of early-onset familial AD. TgF344-AD rats manifest age-dependent cerebral amyloidosis that precedes tauopathy, gliosis, apoptotic loss of neurons in the cerebral cortex and hippocampus, and cognitive disturbance. These results demonstrate progressive neurodegeneration of the Alzheimer type in these animals. The TgF344-AD rat fills a critical need for a next-generation animal model to enable basic and translational AD research. PMID:23575824

A Common Variant of IL-6R is Associated with Elevated IL-6 Pathway Activity in Alzheimer's Disease Brains.

PubMed

Haddick, Patrick C G; Larson, Jessica L; Rathore, Nisha; Bhangale, Tushar R; Phung, Qui T; Srinivasan, Karpagam; Hansen, David V; Lill, Jennie R; Pericak-Vance, Margaret A; Haines, Jonathan; Farrer, Lindsay A; Kauwe, John S; Schellenberg, Gerard D; Cruchaga, Carlos; Goate, Alison M; Behrens, Timothy W; Watts, Ryan J; Graham, Robert R; Kaminker, Joshua S; van der Brug, Marcel

2017-01-01

The common p.D358A variant (rs2228145) in IL-6R is associated with risk for multiple diseases and with increased levels of soluble IL-6R in the periphery and central nervous system (CNS). Here, we show that the p.D358A allele leads to increased proteolysis of membrane bound IL-6R and demonstrate that IL-6R peptides with A358 are more susceptible to cleavage by ADAM10 and ADAM17. IL-6 responsive genes were identified in primary astrocytes and microglia and an IL-6 gene signature was increased in the CNS of late onset Alzheimer's disease subjects in an IL6R allele dependent manner. We conducted a screen to identify variants associated with the age of onset of Alzheimer's disease in APOE ɛ4 carriers. Across five datasets, p.D358A had a meta P = 3 ×10-4 and an odds ratio = 1.3, 95% confidence interval 1.12 -1.48. Our study suggests that a common coding region variant of the IL-6 receptor results in neuroinflammatory changes that may influence the age of onset of Alzheimer's disease in APOE ɛ4 carriers.

Heterogeneity in recent-onset type 1 diabetes - a clinical trial perspective.

PubMed

Bollyky, Jennifer B; Xu, Ping; Butte, Atul J; Wilson, Darrell M; Beam, Craig A; Greenbaum, Carla J

2015-09-01

Type 1 diabetes (T1D) TrialNet is a National Institutes of Health-sponsored clinical trial network aimed at altering the disease course of T1D. The purpose of this study is to evaluate age-dependent heterogeneity in clinical, metabolic and immunologic characteristics of individuals with recent-onset T1D, to identify cohorts of interest and to aid in planning of future studies. Eight hundred eighty-three individuals with recent-onset T1D involved in five TrialNet studies were categorized by age as follows: ≥18 years, 12-17 years, 8-12 years and <8 years. Data were compared with healthy age-matched subjects in the National Health and Nutrition Examination Survey. Only 2.0% of the individuals overall were excluded from trial participation because of insufficient C-peptide values (<0.2 pmol/mL). A disproportionate number of these subjects were <8 years old. Leukopenia was present in 21.2% of individuals and lymphopenia in 11.6%; these frequencies were markedly higher than age-matched healthy National Health and Nutrition Examination Survey population. Of the cohort, 24.5% were overweight or obese. Neither high-risk human leukocyte antigen type DR3 nor DR4 was present in 31% of adults and 21% of children. The ability of recent-onset T1D patients to meet key entry criteria for TrialNet studies, including C-peptide >0.2 pmol/mL, varies by age. Lower C-peptide level requirements for younger participants and other aspects of heterogeneity of recent-onset T1D patients, such as white blood cell count abnormalities and body mass index should be considered in the design of future clinical studies. Copyright © 2015 John Wiley & Sons, Ltd.

Heterogeneity in Recent Onset Type 1 Diabetes – A Clinical Trial Perspective

PubMed Central

Bollyky, Jennifer B.; Xu, Ping; Butte, Atul J.; Wilson, Darrell M.; Beam, Craig A.; Greenbaum, Carla J.

2015-01-01

Background Type 1 Diabetes TrialNet is an NIH-sponsored clinical trial network aimed at altering the disease course of type 1 diabetes. The purpose of this study is to evaluate age-dependent heterogeneity in clinical, metabolic, and immunologic characteristics of individuals with recent-onset type 1 diabetes (T1D), to identify cohorts of interest and to aid in planning of future studies. Methods 883 individuals with recent onset T1D involved in five TrialNet studies were categorized by age as: ≥ 18, age 12-17, ages 8-12, and age <8. Data was compared with healthy age-matched subjects in the National Health and Nutrition Examination Survey. Results While only 2.0 % of individuals overall were excluded due to insufficient C-peptide values (<0.2 pmol/ml), 9.0% of those < age 8 did not meet this entry criteria. Leukopenia was present in 21.2% of individuals and lymphopenia in 11.6%; these frequencies were markedly different than age-matched healthy population. 24.5% of the cohort was overweight or obese. 31.1% of adults and 21.1% of children had neither HLA DR3 nor DR4. Conclusions The ability of recent onset T1D patients to meet key entry criteria for TrialNet studies, including C-peptide >0.2 pmol/ml, varies by age. Lower C-peptide level requirements for younger participants should be considered in the design of future trials. These data also highlight subgroups of type 1 diabetes patients, such as those with abnormal WBC or who are overweight, which allow for targeted studies of etiopathology and interventions. PMID:25689602

Excess Synaptojanin 1 Contributes to Place Cell Dysfunction and Memory Deficits in the Aging Hippocampus in Three Types of Alzheimer's Disease.

PubMed

Miranda, Andre M; Herman, Mathieu; Cheng, Rong; Nahmani, Eden; Barrett, Geoffrey; Micevska, Elizabeta; Fontaine, Gaelle; Potier, Marie-Claude; Head, Elizabeth; Schmitt, Frederick A; Lott, Ira T; Jiménez-Velázquez, Ivonne Z; Antonarakis, Stylianos E; Di Paolo, Gilbert; Lee, Joseph H; Hussaini, S Abid; Marquer, Catherine

2018-06-05

The phosphoinositide phosphatase synaptojanin 1 (SYNJ1) is a key regulator of synaptic function. We first tested whether SYNJ1 contributes to phenotypic variations in familial Alzheimer's disease (FAD) and show that SYNJ1 polymorphisms are associated with age of onset in both early- and late-onset human FAD cohorts. We then interrogated whether SYNJ1 levels could directly affect memory. We show that increased SYNJ1 levels in autopsy brains from adults with Down syndrome (DS/AD) are inversely correlated with synaptophysin levels, a direct readout of synaptic integrity. We further report age-dependent cognitive decline in a mouse model overexpressing murine Synj1 to the levels observed in human sporadic AD, triggered through hippocampal hyperexcitability and defects in the spatial reproducibility of place fields. Taken together, our findings suggest that SYNJ1 contributes to memory deficits in the aging hippocampus in all forms of AD. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Early behavioural changes in familial Alzheimer's disease in the Dominantly Inherited Alzheimer Network.

PubMed

Ringman, John M; Liang, Li-Jung; Zhou, Yan; Vangala, Sitaram; Teng, Edmond; Kremen, Sarah; Wharton, David; Goate, Alison; Marcus, Daniel S; Farlow, Martin; Ghetti, Bernardino; McDade, Eric; Masters, Colin L; Mayeux, Richard P; Rossor, Martin; Salloway, Stephen; Schofield, Peter R; Cummings, Jeffrey L; Buckles, Virginia; Bateman, Randall; Morris, John C

2015-04-01

the degree of self-rated depression more severe (mean Geriatric Depression Scale score of 2.8 versus 1.4, P = 0.006) in mildly symptomatic mutation carriers relative to non-carriers. Anxiety, appetite changes, delusions, and repetitive motor activity were additionally more common in overtly impaired mutation carriers. Similar to studies of late-onset Alzheimer's disease, we demonstrated increased rates of depression, apathy, and other behavioural symptoms in the mildly symptomatic, prodromal phase of autosomal dominant Alzheimer's disease that increased with disease severity. We did not identify any increased psychopathology in mutation carriers over non-carriers during the presymptomatic stage, suggesting these symptoms result when a threshold of neurodegeneration is reached rather than as life-long qualities. Unexpectedly, we found lower rates of depressive symptoms in cognitively asymptomatic mutation carriers. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Problem drinking among Flemish students: beverage type, early drinking onset and negative personal & social consequences.

PubMed

De Bruyn, Sara; Wouters, Edwin; Ponnet, Koen; Van Damme, Joris; Maes, Lea; Van Hal, Guido

2018-02-12

Although alcohol is socially accepted in most Western societies, studies are clear about its associated negative consequences, especially among university and college students. Studies on the relationship between alcohol-related consequences and both beverage type and drinking onset, however, are scarce, especially in a European context. The aim of this research was, therefore, twofold: (1) What is the relationship between beverage type and the negative consequences experienced by students? and (2) Are these consequences determined by early drinking onset? We will examine these questions within the context of a wide range of alcohol-related consequences. The analyses are based on data collected by the inter-university project 'Head in the clouds?', measuring alcohol use among students in Flanders (Belgium). In total, a large dataset consisting of information from 19,253 anonymously participating students was available. Negative consequences were measured using a shortened version of the Core Alcohol and Drug Survey (CADS_D). Data were analysed using negative binomial regression. Results vary depending on the type of alcohol-related consequences: Personal negative consequences occur frequently among daily beer drinkers. However, a high rate of social negative consequences was recorded for both daily beer drinkers and daily spirits drinkers. Finally, early drinking onset was significantly associated with both personal and social negative consequences, and this association was especially strong between beer and spirits drinking onset and social negative consequences. Numerous negative consequences, both personal and social, are related to frequent beer and spirits drinking. Our findings indicate a close association between drinking beer and personal negative consequences as well as between drinking beer and/or spirits and social negative consequences. Similarly, early drinking onset has a major influence on the rates of both personal and social negative consequences

Genetic Comparison of Symptomatic and Asymptomatic Persons With Alzheimer Disease Neuropathology.

PubMed

Monsell, Sarah E; Mock, Charles; Fardo, David W; Bertelsen, Sarah; Cairns, Nigel J; Roe, Catherine M; Ellingson, Sally R; Morris, John C; Goate, Alison M; Kukull, Walter A

2017-01-01

The objective was to determine whether symptomatic and asymptomatic persons with Alzheimer disease (AD) neuropathology have different allele counts for single-nucleotide polymorphisms that have been associated with clinical late-onset AD. Data came from the National Alzheimer's Coordinating Center Uniform Data Set and Neuropathology Data Set, and the Alzheimer's Disease Genetics Consortium (ADGC). Participants had low to high AD neuropathologic change. The 22 known/suspected genes associated with late-onset AD were considered. "Symptomatic" was defined as Clinical Dementia Rating global score >0. Sixty-eight asymptomatic and 521 symptomatic participants met inclusion criteria. Single-nucleotide polymorphisms associated with ABCA7 [odds ratio (OR)=1.66; 95% confidence interval (CI), 1.03-2.85] and MAPT (OR=2.18; CI, 1.26-3.77) were associated with symptomatic status. In stratified analyses, loci containing CD2AP (OR=0.35; 95% CI, 0.16-0.74), ZCWPW1 (OR=2.98; 95% CI, 1.34-6.86), and MAPT (OR=3.73, 95% CI, 1.30-11.76) were associated with symptomatic status in APOE e4 carriers. These findings potentially explain some of the variation in whether a person with AD neuropathology expresses symptoms. Understanding why some people remain cognitively normal despite having AD neuropathology could identify pathways to disease heterogeneity and guide treatment trials.

The Role of Genetics in Advancing Precision Medicine for Alzheimer's Disease-A Narrative Review.

PubMed

Freudenberg-Hua, Yun; Li, Wentian; Davies, Peter

2018-01-01

Alzheimer's disease (AD) is the most common type of dementia, which has a substantial genetic component. AD affects predominantly older people. Accordingly, the prevalence of dementia has been rising as the population ages. To date, there are no effective interventions that can cure or halt the progression of AD. The only available treatments are the management of certain symptoms and consequences of dementia. The current state-of-the-art medical care for AD comprises three simple principles: prevent the preventable, achieve early diagnosis, and manage the manageable symptoms. This review provides a summary of the current state of knowledge of risk factors for AD, biological diagnostic testing, and prospects for treatment. Special emphasis is given to recent advances in genetics of AD and the way genomic data may support prevention, early intervention, and development of effective pharmacological treatments. Mutations in the APP, PSEN1 , and PSEN2 genes cause early onset Alzheimer's disease (EOAD) that follows a Mendelian inheritance pattern. For late onset Alzheimer's disease (LOAD), APOE4 was identified as a major risk allele more than two decades ago. Population-based genome-wide association studies of late onset AD have now additionally identified common variants at roughly 30 genetic loci. Furthermore, rare variants (allele frequency <1%) that influence the risk for LOAD have been identified in several genes. These genetic advances have broadened our insights into the biological underpinnings of AD. Moreover, the known genetic risk variants could be used to identify presymptomatic individuals at risk for AD and support diagnostic assessment of symptomatic subjects. Genetic knowledge may also facilitate precision medicine. The goal of precision medicine is to use biological knowledge and other health information to predict individual disease risk, understand disease etiology, identify disease subcategories, improve diagnosis, and provide personalized treatment

No association of toll-like receptor 2 polymorphisms with Alzheimer's disease in Han Chinese.

PubMed

Yu, Jin-Tai; Sun, Yan-Ping; Ou, Jiang-Rong; Cui, Wei-Zhen; Zhang, Wei; Tan, Lan

2011-10-01

Toll-like receptor 2 (TLR2) represents a reasonable functional and positional candidate gene for Alzheimer's disease (AD) as it is located under the linkage region of AD on chromosome 4q, and is functionally involved in the microglia-mediated inflammatory response and amyloid β (Aβ) clearance. In the current study, 7 single nucleotide polymorphisms (SNPs) that span the TLR2 were selected and their associations with late-onset AD (LOAD) risk were assessed in a case-control sample comprising 785 individuals in a Han Chinese population. No significant differences in the frequency of TLR2 alleles, genotypes, and haplotypes in the AD cases were detected compared with the controls. TLR2 gene might not play a major role in the genetic predisposition to late-onset Alzheimer's disease in this population. Copyright © 2011 Elsevier Inc. All rights reserved.

The genetics of Alzheimer disease.

PubMed

Tanzi, Rudolph E

2012-10-01

Family history is the second strongest risk factor for Alzheimer disease (AD) following advanced age. Twin and family studies indicate that genetic factors are estimated to play a role in at least 80% of AD cases. The inheritance of AD exhibits a dichotomous pattern. On one hand, rare mutations in APP, PSEN1, and PSEN2 virtually guarantee early-onset (<60 years) familial AD, which represents ∼5% of AD. On the other hand, common gene polymorphisms, such as the ε4 and ε2 variants of the APOE gene, can influence susceptibility for ∼50% of the common late-onset AD. These four genes account for 30%-50% of the inheritability of AD. Genome-wide association studies have recently led to the identification of 11 additional AD candidate genes. This paper reviews the past, present, and future attempts to elucidate the complex and heterogeneous genetic underpinnings of AD.

Association analysis of 528 intra-genic SNPs in a region of chromosome 10 linked to late onset Alzheimer's disease.

PubMed

Morgan, A R; Hamilton, G; Turic, D; Jehu, L; Harold, D; Abraham, R; Hollingworth, P; Moskvina, V; Brayne, C; Rubinsztein, D C; Lynch, A; Lawlor, B; Gill, M; O'Donovan, M; Powell, J; Lovestone, S; Williams, J; Owen, M J

2008-09-05

Late-onset Alzheimer's disease (LOAD) is a genetically complex neurodegenerative disorder. Currently, only the epsilon4 allele of the Apolipoprotein E gene has been identified unequivocally as a genetic susceptibility factor for LOAD. Others remain to be found. In 2002 we observed genome-wide significant evidence of linkage to a region on chromosome 10q11.23-q21.3 [Myers et al. (2002) Am J Med Genet 114:235-244]. Our objective in this study was to test every gene within the maximum LOD-1 linkage region, for association with LOAD. We obtained results for 528 SNPs from 67 genes, with an average density of 1 SNP every 10 kb within the genes. We demonstrated nominally significant association with LOAD for 4 SNPs: rs1881747 near DKK1 (P = 0.011, OR = 1.24), rs2279420 in ANK3 (P = 0.022, OR = 0.79), rs2306402 in CTNNA3 (P = 0.024, OR = 1.18), and rs5030882 in CXXC6 (P = 0.046, OR = 1.29) in 1,160 cases and 1,389 controls. These results would not survive correction for multiple testing but warrant attempts at confirmation in independent samples. 2007 Wiley-Liss, Inc.

Biomarkers for Alzheimer's disease: academic, industry and regulatory perspectives.

PubMed

Hampel, Harald; Frank, Richard; Broich, Karl; Teipel, Stefan J; Katz, Russell G; Hardy, John; Herholz, Karl; Bokde, Arun L W; Jessen, Frank; Hoessler, Yvonne C; Sanhai, Wendy R; Zetterberg, Henrik; Woodcock, Janet; Blennow, Kaj

2010-07-01

Advances in therapeutic strategies for Alzheimer's disease that lead to even small delays in onset and progression of the condition would significantly reduce the global burden of the disease. To effectively test compounds for Alzheimer's disease and bring therapy to individuals as early as possible there is an urgent need for collaboration between academic institutions, industry and regulatory organizations for the establishment of standards and networks for the identification and qualification of biological marker candidates. Biomarkers are needed to monitor drug safety, to identify individuals who are most likely to respond to specific treatments, to stratify presymptomatic patients and to quantify the benefits of treatments. Biomarkers that achieve these characteristics should enable objective business decisions in portfolio management and facilitate regulatory approval of new therapies.

Genetic Aspects of Alzheimer Disease

PubMed Central

Williamson, Jennifer; Goldman, Jill; Marder, Karen S.

2011-01-01

Background Alzheimer disease (AD) is a genetically complex disorder. Mutations in 3 genes, presenilin 1, amyloid precursor protein, and presenilin 2, lead to early-onset familial AD in rare families with onset of disease occurring prior to age 65. Specific polymorphisms in apolipoprotein E are associated with the more common, late-onset AD occurring after age 65. In this review, we discuss current advances in AD genetics, the implications of the known AD genes, presenilin 1, presenilin 2, amyloid precursor protein, and apolipoprotein E, and other possible genes on the clinical diagnosis, treatment, and genetic counseling of patients and families with early- and late-onset AD. Review Summary In addition to the mutations in 4 known genes associated with AD, mutations in other genes may be implicated in the pathogenesis of the disease. Most recently, 2 different research groups have reported genetic association between 2 genes, sortilin-related receptor and GAB2, and AD. These associations have not changed the diagnostic and medical management of AD. Conclusions New research in the genetics of AD have implicated novel genes as having a role in the disease, but these findings have not been replicated nor have specific disease causing mutations been identified. To date, clinical genetic testing is limited to familial early-onset disease for symptomatic individuals and asymptomatic relatives and, although not recommended, amyloid precursor protein apolipoprotein E testing as an adjunct to diagnosis of symptomatic individuals. PMID:19276785

NMR structure of the Arctic mutation of the Alzheimer's Aβ(1-40) peptide docked to SDS micelles

NASA Astrophysics Data System (ADS)

Usachev, K. S.; Filippov, A. V.; Khairutdinov, B. I.; Antzutkin, O. N.; Klochkov, V. V.

2014-11-01

The “Arctic” point mutation of the Alzheimer's amyloid β-peptide is a rare mutation leading to an early onset of Alzheimer's disease. The peptide may interact with neuronal membranes, where it can provide its toxic effects. We used 2D NMR spectroscopy to investigate the conformation of the “Arctic” mutant of Aβ1-40 Alzheimer's amyloid peptide in sodium dodecyl sulfate micelle solutions, which are the type of amphiphilic structures mimicking some properties of biomembranes. The study showed that the Arctic mutant of Aβ1-40 interacts with the surface of SDS micelles mainly through the Leu17-Asn27 310-helical region, while the Ile31-Val40 region is buried in the hydrophobic interior of the micelle. In contrast, wild-type Aβ1-40 interacts with SDS micelles through the Lys16-Asp23 α-helical region and Gly29-Met35. Both the Arctic mutant and the wild-type Aβ1-40 peptides interactions with SDS micelles are hydrophobic in nature. Aβ peptides are thought to be capable of forming pores in biomembranes that can cause changes in neuronal and endothelial cell membrane permeability. It has also been shown that Aβ peptides containing the “Arctic” mutation are more neurotoxic and aggregate more readily than the wild-type Aβ peptides at physiological conditions. Here, we propose that the extension of the helical structure of Leu17-Asn27 and a high aliphaticity (neutrality) of the C-terminal region in the Arctic Aβ peptides are consistent with the idea that formation of ion-permeable pores by Aβ oligomers may be one of prevailing mechanisms of a larger neuronal toxicity of the Arctic Aβ compared to the wild-type Aβ peptides, independent of oxidative damage and lipid peroxidation.

Major depressive disorder and type II diabetes mellitus: mechanisms underlying risk for Alzheimer's disease.

PubMed

Cha, Danielle S; Carvalho, Andre F; Rosenblat, Joshua D; Ali, Muna M; McIntyre, Roger S

2014-01-01

Objectives/Introduction: Major Depressive Disorder is associated age-related medical conditions (e.g., diabetes mellitus type II, Alzheimer's disease) that frequently manifest at an earlier age, contributing to excess and premature mortality. The foregoing observation provides the impetus to further refine potential mechanisms and molecular pathways subserving these disorders in order to more effectively treat these clinical populations by aiming to reduce and prevent cognitive impairment as well as downstream neurodegeneration. A review of computerized databases was performed to identify original studies that investigated the impact of the independent and comorbid association of major depressive disorder and type II diabetes mellitus on cognitive function and conversion to Alzheimer's disease. English-written articles were selected for review based on the adequacy of sample size, the use of standardized diagnostic instruments, and validated assessment measures. Individuals with persistent neuropsychiatric illness account for a disproportionate overall burden of disability mediated largely by decrements in cognitive performance. Mixed results from epidemiological and clinical studies suggest that insulin may mediate and/or moderate risk for cognitive dysfunction in subsets of individuals. Moreover, physiological changes, such as insulin resistance and the activation of neuroimmunoinflammatory systems result in glial and neuroendangerment. Disturbances in the metabolic milieu exert a neurotoxic effect on the central nervous system and poses a hazard to other organ systems.

The Effects of Alzheimer's Disease on Close Relationships between Patients and Caregivers.

ERIC Educational Resources Information Center

Blieszner, Rosemary; Shifflett, Peggy A.

1990-01-01

Interviewed 11 caregivers for early-stage Alzheimer's patients to investigate changes in relationships concurrently with onset and progress of disease. Over 18 months, intimacy declined in both spouse and parent-child relationships. Caregivers were saddened at loss of reciprocal aspects of relationship and had difficulty coping with uncertain…

Elevation of Glutathione as a Therapeutic Strategy in Alzheimer Disease

PubMed Central

Pocernich, Chava B.; Butterfield, D. Allan

2011-01-01

Oxidative stress has been associated with the onset and progression of mild cognitive impairment (MCI) and Alzheimer disease (AD). AD and MCI brain and plasma display extensive oxidative stress as indexed by protein oxidation, lipid peroxidation, free radical formation, DNA oxidation, and decreased antioxidants. The most abundant endogenous antioxidant, glutathione, plays a significant role in combating oxidative stress. The ratio of oxidized to reduced glutathione is utilized as a measure of intensity of oxidative stress. Antioxidants have long been considered as an approach to slow down AD progression. In this review, we focus on the elevation on glutathione through N-acytl-cysteine (NAC) and γ-glutamylcysteine ethyl ester (GCEE) as a potential therapeutic approach for Alzheimer disease. PMID:22015471

Alzheimer's Disease Phenotypes and Genotypes Associated with Mutations in Presenilin 2

ERIC Educational Resources Information Center

Jayadev, Suman; Leverenz, James B.; Steinbart, Ellen; Stahl, Justin; Klunk, William; Yu, Cheng-En; Bird, Thomas D.

2010-01-01

Mutations in presenilin 2 are rare causes of early onset familial Alzheimer's disease. Eighteen presenilin 2 mutations have been reported, although not all have been confirmed pathogenic. Much remains to be learned about the range of phenotypes associated with these mutations. We have analysed our unique collection of 146 affected cases in 11…

Severe hypertriglyceridemia at new onset type 1 diabetes mellitus.

PubMed

Fick, Tyler; Jack, Julie; Pyle-Eilola, Amy L; Henry, Rohan K

2017-08-28

Severe hypertriglyceridemia (HTG) as well as diabetic ketoacidosis (DKA) are complications of type 1 diabetes (T1DM). HTG is an exceedingly rare complication in the pediatric population and herein we report a case of HTG at new-onset T1DM in DKA and discuss management and potential complications. An 11-year-old previously well patient with a history of fatigue and weight loss presented with: glucose >600 mg/dL, venous blood gas: pH 7.26, pCO2 20 mmHg, PO2 101 mmHg and base deficit 13 with triglyceride level 3573 mg/dL. An insulin drip was continued past criteria for discontinuation to facilitate lipoprotein lipase-based triglyceride metabolism. Lipemia secondary to severe HTG, though exceedingly rare, may exist in new onset T1DM with DKA. Complicating the diagnosis is the possibility of an analytical error from lipemia causing incongruence in diagnostic criteria. Clinicians should rely on clinical criteria for management and should consider HTG if laboratory data is inconsistent with the clinical picture.

[Clinical aspects of Alzheimer disease].

PubMed

Soto, Maria; Reynish, Emma; Nourhashémi, Fati; Vellas, Bruno

2007-10-01

Alzheimer disease is diagnosed in only half of the patients with this disease in France. In its typical form, it is characterized at the onset by short-term memory problems, repetitive and unusual oversights and forgetfulness, and difficulties in learning new information. Dementia is responsible for more than 50% of the need for care in the elderly. Disease progression is accompanied by noncognitive complications. The 3 most frequent are psychological and behavioral symptoms, weight loss, and impaired balance and walking. Its progressive nature and potential complications underline the need for multidisciplinary management for patients and their families, with regular medical follow-up.

Survival of Alzheimer's disease patients in Korea.

PubMed

Go, Seok Min; Lee, Kang Soo; Seo, Sang Won; Chin, Juhee; Kang, Sue J; Moon, So Young; Na, Duk L; Cheong, Hae-Kwan

2013-01-01

The natural history of Alzheimer's disease (AD) has rarely been studied in the Korean population. Our study on survival analyses in Korean AD patients potentially provides a basis for cross-cultural comparisons. We studied 724 consecutive patients from a memory disorder clinic in a tertiary hospital in Seoul, who were diagnosed as having AD between April 1995 and December 2005. Deaths were identified by the Statistics Korea database. The Kaplan-Meier method was used for survival analysis, and a Cox proportional hazard model was used to assess factors related to patient survival. The overall median survival from the onset of first symptoms and from the time of diagnosis was 12.6 years (95% confidence interval 11.7-13.4) and 9.3 years (95% confidence interval 8.7-9.9), respectively. The age of onset, male gender, history of diabetes mellitus, lower Mini-Mental State Examination score, and higher Clinical Dementia Rating score were negatively associated with survival. There was a reversal of risk of AD between early-onset and later-onset AD, 9.1 years after onset. The results of our study show a different pattern of survival compared to those studies carried out with western AD populations. Mortality risk of early-onset AD varied depending on the duration of follow-up. Copyright © 2013 S. Karger AG, Basel.

Disrupted rich club network in behavioral variant frontotemporal dementia and early-onset Alzheimer's disease

PubMed Central

Daianu, Madelaine; Mezher, Adam; Mendez, Mario F.; Jahanshad, Neda; Jimenez, Elvira E.; Thompson, Paul M.

2016-01-01

In network analysis, the so-called ‘rich club’ describes the core areas of the brain that are more densely interconnected among themselves than expected by chance, and has been identified as a fundamental aspect of the human brain connectome. This is the first in-depth diffusion imaging study to investigate the rich club along with other organizational changes in the brain's anatomical network in behavioral frontotemporal dementia (bvFTD), and a matched cohort with early-onset Alzheimer's disease (EOAD). Our study sheds light on how bvFTD and EOAD affect connectivity of white matter fiber pathways in the brain, revealing differences and commonalities in the connectome among the dementias. To analyze the breakdown in connectivity, we studied 3 groups: 20 bvFTD, 23 EOAD and 37 healthy elderly controls. All participants were scanned with diffusion-weighted MRI, and based on whole-brain probabilistic tractography and cortical parcellations, we analyzed the rich club of the brain's connectivity network. This revealed distinct patterns of disruption in both forms of dementia. In the connectome, we detected less disruption overall in EOAD than in bvFTD (False Discovery Rate (FDR) critical Pperm=5.7×10−3, 10,000 permutations), with more involvement of richly interconnected areas of the brain (chi-squared PΧ2=1.4×10−4) – predominantly posterior cognitive alterations. In bvFTD, we found a greater spread of disruption including the rich club (FDR critical Pperm=6×10−4), but especially more peripheral alterations (PΧ2=6.5×10−3), particularly in medial frontal areas of the brain, in line with the known behavioral socioemotional deficits seen in these patients. PMID:26678225

Genetic variants associated with susceptibility to psychosis in late-onset Alzheimer's disease families.

PubMed

Barral, Sandra; Vardarajan, Badri N; Reyes-Dumeyer, Dolly; Faber, Kelley M; Bird, Thomas D; Tsuang, Debby; Bennett, David A; Rosenberg, Roger; Boeve, Bradley F; Graff-Radford, Neill R; Goate, Alison M; Farlow, Martin; Lantigua, Rafael; Medrano, Martin Z; Wang, Xinbing; Kamboh, M Ilyas; Barmada, Mahmud Muhiedine; Schaid, Daniel J; Foroud, Tatiana M; Weamer, Elise A; Ottman, Ruth; Sweet, Robert A; Mayeux, Richard

2015-11-01

Psychotic symptoms are frequent in late-onset Alzheimer's disease (LOAD) patients. Although the risk for psychosis in LOAD is genetically mediated, no genes have been identified. To identify loci potentially containing genetic variants associated with risk of psychosis in LOAD, a total of 263 families from the National Institute of Aging-LOAD cohort were classified into psychotic (LOAD+P, n = 215) and nonpsychotic (LOAD-P, n = 48) families based on the presence/absence of psychosis during the course of LOAD. The LOAD+P families yielded strong evidence of linkage on chromosome 19q13 (two-point [2-pt] ​logarithm of odds [LOD] = 3.8, rs2285513 and multipoint LOD = 2.7, rs541169). Joint linkage and association in 19q13 region detected strong association with rs2945988 (p = 8.7 × 10(-7)). Linkage results for the LOAD-P families yielded nonsignificant 19q13 LOD scores. Several 19q13 single-nucleotide polymorphisms generalized the association of LOAD+P in a Caribbean Hispanic (CH) cohort, and the strongest signal was rs10410711 (pmeta = 5.1 × 10(-5)). A variant located 24 kb upstream of rs10410711 and rs10421862 was strongly associated with LOAD+P (pmeta = 1.0 × 10(-5)) in a meta-analysis of the CH cohort and an additional non-Hispanic Caucasian dataset. Identified variants rs2945988 and rs10421862 affect brain gene expression levels. Our results suggest that genetic variants in genes on 19q13, some of which are involved in brain development and neurodegeneration, may influence the susceptibility to psychosis in LOAD patients. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

From here to epilepsy: the risk of seizure in patients with Alzheimer's disease.

PubMed

Nicastro, Nicolas; Assal, Frédéric; Seeck, Margitta

2016-03-01

To describe the association between Alzheimer's disease and seizures by reviewing epidemiological data from available literature and to assess the putative pathophysiological links between neurodegeneration and altered cortical excitability. We also discuss specific antiepileptic treatment strategies in patients with Alzheimer's disease, as well as transient epileptic amnesia as a possible crossroads between degeneration and epilepsy. Regarding epidemiology, we searched publications in Pubmed, Medline, Scopus and Web of Science (until September 2015) using the keywords "incidence", "prevalence" and "frequency", as well as "Alzheimer's disease" and "seizures". In addition, therapeutic aspects for seizures in Alzheimer's disease were searched using the key words "antiepileptic drugs", "seizure treatment" and "Alzheimer". The prevalence and incidence rates of seizures were found to be increased 2 to 6-fold in patients with Alzheimer's disease compared to age-adjusted control patients. Treatment strategies have mainly been extrapolated from elderly patients without dementia, except for one single randomised trial, in which levetiracetam, lamotrigine and phenobarbital efficacy and tolerance were investigated in patients with Alzheimer's disease. Mouse models appear to show a major role of amyloid precursor protein and its cleavage products in the generation of cortical hyperexcitability. A link between Alzheimer's disease and epilepsy has long been described and recent cohort studies have more clearly delineated risk factors associated with the genesis of seizures, such as early onset and possibly severity of dementia. As genetic forms of Alzheimer's disease and experimental mouse models suggest, beta-amyloid may play a prominent role in the propagation of synchronised abnormal discharges, perhaps more via an excitatory mode than a direct neurodegenerative effect.

Type 2 diabetes mellitus in the pathophysiology of Alzheimer's disease.

PubMed

de Nazareth, Aparecida Marcelino

2017-01-01

Both Alzheimer's disease (AD) and type 2 diabetes mellitus (DM) are two common forms of disease worldwide and many studies indicate that people with diabetes, especially DM, are at higher risk of developing AD. AD is characterized by progressive cognitive decline and accumulation of β-amyloid (Aβ) forming senile plaques. DM is a metabolic disorder characterized by hyperglycemia in the context of insulin resistance and relative lack of insulin. Both diseases also share common characteristics such as loss of cognitive function and inflammation. Inflammation resulting from Aβ further induces production of Aβ 1-42 peptides. Inflammation due to overnutrition induces insulin resistance and consequently DM. Memory deficit and a decrease in GLUT4 and hippocampal insulin signaling have been observed in animal models of insulin resistance. The objective of this review was to show the shared characteristics of AD and DM.

Caregiver Report of Prevalence and Appearance Order of Linguistic Symptoms in Alzheimer's Patients.

ERIC Educational Resources Information Center

Bayles, Kathryn A.; Tomoeda, Cheryl K.

1991-01-01

Interviewed primary caregivers of 99 Alzheimer's patients about existence and appearance order of linguistic symptoms to study disease effects on communication. Found that prevalence of linguistic symptoms strongly correlated with order of symptom appearance. Discusses symptom prevalence and order of appearance in relation to onset of…

The Genetics of Alzheimer Disease

PubMed Central

Tanzi, Rudolph E.

2012-01-01

Family history is the second strongest risk factor for Alzheimer disease (AD) following advanced age. Twin and family studies indicate that genetic factors are estimated to play a role in at least 80% of AD cases. The inheritance of AD exhibits a dichotomous pattern. On one hand, rare mutations in APP, PSEN1, and PSEN2 virtually guarantee early-onset (<60 years) familial AD, which represents ∼5% of AD. On the other hand, common gene polymorphisms, such as the ε4 and ε2 variants of the APOE gene, can influence susceptibility for ∼50% of the common late-onset AD. These four genes account for 30%–50% of the inheritability of AD. Genome-wide association studies have recently led to the identification of 11 additional AD candidate genes. This paper reviews the past, present, and future attempts to elucidate the complex and heterogeneous genetic underpinnings of AD. PMID:23028126

Alzheimer Disease

PubMed Central

Apostolova, Liana G.

2016-01-01

ABSTRACT Purpose of Review: This article discusses the recent advances in the diagnosis and treatment of Alzheimer disease (AD). Recent Findings: In recent years, significant advances have been made in the fields of genetics, neuroimaging, clinical diagnosis, and staging of AD. One of the most important recent advances in AD is our ability to visualize amyloid pathology in the living human brain. The newly revised criteria for diagnosis of AD dementia embrace the use for biomarkers as supportive evidence for the underlying pathology. Guidelines for the responsible use of amyloid positron emission tomography (PET) have been developed, and the clinical and economic implications of amyloid PET imaging are actively being explored. Summary: Our improved understanding of the clinical onset, progression, neuroimaging, pathologic features, genetics, and other risk factors for AD impacts the approaches to clinical diagnosis and future therapeutic interventions. PMID:27042902

Presenilins and γ-Secretase: Structure, Function, and Role in Alzheimer Disease

PubMed Central

De Strooper, Bart; Iwatsubo, Takeshi; Wolfe, Michael S.

2012-01-01

Presenilins were first discovered as sites of missense mutations responsible for early-onset Alzheimer disease (AD). The encoded multipass membrane proteins were subsequently found to be the catalytic components of γ-secretases, membrane-embedded aspartyl protease complexes responsible for generating the carboxyl terminus of the amyloid β-protein (Aβ) from the amyloid protein precursor (APP). The protease complex also cleaves a variety of other type I integral membrane proteins, most notably the Notch receptor, signaling from which is involved in many cell differentiation events. Although γ-secretase is a top target for developing disease-modifying AD therapeutics, interference with Notch signaling should be avoided. Compounds that alter Aβ production by γ-secretase without affecting Notch proteolysis and signaling have been identified and are currently at various stages in the drug development pipeline. PMID:22315713

Are Tanycytes the Missing Link Between Type 2 Diabetes and Alzheimer's Disease?

PubMed

Raikwar, Sudhanshu P; Bhagavan, Sachin M; Ramaswamy, Swathi Beladakere; Thangavel, Ramasamy; Dubova, Iuliia; Selvakumar, Govindhasamy Pushpavathi; Ahmed, Mohammad Ejaz; Kempuraj, Duraisamy; Zaheer, Smita; Iyer, Shankar; Zaheer, Asgar

2018-05-24

Tanycytes are highly specialized bipolar ependymal cells that line the ventrolateral wall and the floor of the third ventricle in the brain and form a blood-cerebrospinal fluid barrier at the level of the median eminence. They play a pivotal role in regulating metabolic networks that control body weight and energy homeostasis. Due to the glucosensing function of tanycytes, they could be considered as a critical player in the pathogenesis of type 2 diabetes. Genetic fate mapping studies have established the role of tanycytes for the newly detected adult hypothalamic neurogenesis with important implications for metabolism as well as pathophysiology of various neurodegenerative diseases. We believe that a comprehensive understanding of the physiological mechanisms underlying their neuroplasticity, glucosensing, and cross talk with endothelial cells will enable us to achieve metabolic homeostasis in type 2 diabetes patients and possibly delay the progression of Alzheimer's disease and hopefully improve cognitive function.

1H MRS spectroscopy in preclinical autosomal dominant Alzheimer disease.

PubMed

Joe, Elizabeth; Medina, Luis D; Ringman, John M; O'Neill, Joseph

2018-06-16

1 H magnetic resonance spectroscopy (MRS) can reveal changes in brain biochemistry in vivo in humans and has been applied to late onset Alzheimer disease (AD). Carriers of mutations for autosomal dominant Alzheimer disease (ADAD) may show changes in levels of metabolites prior to the onset of clinical symptoms. Proton MR spectra were acquired at 1.5 T for 16 cognitively asymptomatic or mildly symptomatic mutation carriers (CDR < 1) and 11 non-carriers as part of a comprehensive cross-sectional study of preclinical ADAD. Levels of N-acetyl-aspartate+N-acetyl-aspartyl-glutamate (NAA), glutamate/glutamine (Glx), creatine/phosphocreate (Cr), choline (Cho), and myo-inositol (mI) in the left and right anterior cingulate and midline posterior cingulate and precuneus were compared between mutation carriers (MCs) and non-carriers (NCs) using multivariate analysis of variance with age as a covariate. Among MCs, correlations between metabolite levels and time until expected age of dementia diagnosis were calculated. MCs had significantly lower levels of NAA and Glx in the left pregenual anterior cingulate cortex, and lower levels of NAA and higher levels of mI and Cho in the precuneus compared to NCs. Increased levels of mI were seen in these regions in association with increased proximity to expected age of dementia onset. MRS shows effects of ADAD similar to those seen in late onset AD even during the preclinical period including lower levels of NAA and higher levels of mI. These indices of neuronal and glial dysfunction might serve as surrogate outcome measures in prevention studies of putative disease-modifying agents.

Identification of novel loci for Alzheimer disease and replication of CLU, PICALM, and BIN1 in Caribbean Hispanic individuals.

PubMed

Lee, Joseph H; Cheng, Rong; Barral, Sandra; Reitz, Christiane; Medrano, Martin; Lantigua, Rafael; Jiménez-Velazquez, Ivonne Z; Rogaeva, Ekaterina; St George-Hyslop, Peter H; Mayeux, Richard

2011-03-01

To identify novel loci for late-onset Alzheimer disease (LOAD) in Caribbean Hispanic individuals and to replicate the findings in a publicly available data set from the National Institute on Aging Late-Onset Alzheimer's Disease Family Study. Nested case-control genome-wide association study. The Washington Heights-Inwood Columbia Aging Project and the Estudio Familiar de Influencia Genetica de Alzheimer study. Five hundred forty-nine affected and 544 unaffected individuals of Caribbean Hispanic ancestry. The Illumina HumanHap 650Y chip for genotyping. Clinical diagnosis or pathologically confirmed diagnosis of LOAD. The strongest support for allelic association was for rs9945493 on 18q23 (P=1.7×10(-7)), but 22 additional single-nucleotide polymorphisms (SNPs) had a P value less than 9×10(-6) under 3 different analyses: unadjusted and stratified by the presence or absence of the APOE ε4 allele. Of these SNPs, 5 SNPs (rs4669573 and rs10197851 on 2p25.1; rs11711889 on 3q25.2; rs1117750 on 7p21.1; and rs7908652 on 10q23.1) were associated with LOAD in an independent cohort from the National Institute on Aging Late-Onset Alzheimer's Disease Family Study. We also replicated genetic associations for CLU, PICALM, and BIN1. Our genome-wide search of Caribbean Hispanic individuals identified several novel genetic variants associated with LOAD and replicated these associations in a white cohort. We also replicated associations in CLU, PICALM, and BIN1 in the Caribbean Hispanic cohort.

Brain differences in infants at differential genetic risk for late-onset Alzheimer disease: a cross-sectional imaging study.

PubMed

Dean, Douglas C; Jerskey, Beth A; Chen, Kewei; Protas, Hillary; Thiyyagura, Pradeep; Roontiva, Auttawat; O'Muircheartaigh, Jonathan; Dirks, Holly; Waskiewicz, Nicole; Lehman, Katie; Siniard, Ashley L; Turk, Mari N; Hua, Xue; Madsen, Sarah K; Thompson, Paul M; Fleisher, Adam S; Huentelman, Matthew J; Deoni, Sean C L; Reiman, Eric M

2014-01-01

Converging evidence suggests brain structure alterations may precede overt cognitive impairment in Alzheimer disease by several decades. Early detection of these alterations holds inherent value for the development and evaluation of preventive treatment therapies. To compare magnetic resonance imaging measurements of white matter myelin water fraction (MWF) and gray matter volume (GMV) in healthy infant carriers and noncarriers of the apolipoprotein E (APOE) ε4 allele, the major susceptibility gene for late-onset AD. Quiet magnetic resonance imaging was performed at an academic research imaging center on 162 healthy, typically developing 2- to 25-month-old infants with no family history of Alzheimer disease or other neurological or psychiatric disorders. Cross-sectional measurements were compared in the APOE ε4 carrier and noncarrier groups. White matter MWF was compared in one hundred sixty-two 2- to 25-month-old sleeping infants (60 ε4 carriers and 102 noncarriers). Gray matter volume was compared in a subset of fifty-nine 6- to 25-month-old infants (23 ε4 carriers and 36 noncarriers), who remained asleep during the scanning session. The carrier and noncarrier groups were matched for age, gestational duration, birth weight, sex ratio, maternal age, education, and socioeconomic status. Automated algorithms compared regional white matter MWF and GMV in the carrier and noncarrier groups and characterized their associations with age. Infant ε4 carriers had lower MWF and GMV measurements than noncarriers in precuneus, posterior/middle cingulate, lateral temporal, and medial occipitotemporal regions, areas preferentially affected by AD, and greater MWF and GMV measurements in extensive frontal regions and measurements were also significant in the subset of 2- to 6-month-old infants (MWF differences, P < .05, after correction for multiple comparisons; GMV differences, P < .001, uncorrected for multiple comparisons). Infant ε4 carriers also exhibited an

A quantitative comparison of plaque types in Alzheimer's disease and senile dementia of the Lewy body type.

PubMed

McKenzie, J E; Edwards, R J; Gentleman, S M; Ince, P G; Perry, R H; Royston, M C; Roberts, G W

1996-01-01

In a previous study we reported no difference in the overall beta-amyloid protein (beta AP) load between Alzheimer's disease (AD) and senile dementia of the Lewy body type (SDLT). However, it is possible that differences in the morphology of beta AP plaque types exist, analogous to the differences in cytoskeletal pathology found in these two disorders. We have carried out a quantitative image analysis of plaque subtypes in the temporal lobe of AD (n = 8), SDLT (n = 9) and control (n = 11) cases. Measurements of beta AP load and plaque density were consistently higher in AD and SDLT than in controls. When AD and SDLT cases were compared no differences were seen in either the density or relative proportions of classic and diffuse plaques. Based on these results we suggest that the variation in the clinical course of these diseases reflects differences in the cytoskeletal pathology, whereas the final stages of profound dementia common to both disorders is associated with the deposition of beta AP.

Accelerating Alzheimer's disease drug innovations from the research pipeline to patients.

PubMed

Goldman, Dana P; Fillit, Howard; Neumann, Peter

2018-03-23

In June 2017, a diverse group of experts in Alzheimer's disease convened to discuss how to accelerate getting new drugs to patients to both prevent and treat the disease. Participants concluded that we need a more robust, diversified drug development pipeline. Strategic policy measures can help keep new Alzheimer's disease therapies (whether to treat symptoms, prevent onset, or cure) affordable for patients while supporting innovation and facilitating greater information sharing among payers, providers, researchers, and the public, including a postmarket surveillance study system, disease registries, innovative payment approaches, harmonizing federal agency review requirements, allowing conditional coverage for promising therapeutics and technology while additional data are collected, and opening up channels for drug companies to communicate with payers (and each other) about data and outcomes. To combat reimbursement issues, policy makers should address the latency time between potential treatment-which may be costly and fall on private payers-and societal benefits that accrue elsewhere. Copyright © 2018 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Genomic convergence to identify candidate genes for Alzheimer disease on chromosome 10

PubMed Central

Liang, Xueying; Slifer, Michael; Martin, Eden R.; Schnetz-Boutaud, Nathalie; Bartlett, Jackie; Anderson, Brent; Züchner, Stephan; Gwirtsman, Harry; Gilbert, John R.; Pericak-Vance, Margaret A.; Haines, Jonathan L.

2009-01-01

A broad region of chromosome 10 (chr10) has engendered continued interest in the etiology of late-onset Alzheimer Disease (LOAD) from both linkage and candidate gene studies. However, there is a very extensive heterogeneity on chr10. We converged linkage analysis and gene expression data using the concept of genomic convergence that suggests that genes showing positive results across multiple different data types are more likely to be involved in AD. We identified and examined 28 genes on chr10 for association with AD in a Caucasian case-control dataset of 506 cases and 558 controls with substantial clinical information. The cases were all LOAD (minimum age at onset ≥ 60 years). Both single marker and haplotypic associations were tested in the overall dataset and 8 subsets defined by age, gender, ApoE and clinical status. PTPLA showed allelic, genotypic and haplotypic association in the overall dataset. SORCS1 was significant in the overall data sets (p=0.0025) and most significant in the female subset (allelic association p=0.00002, a 3-locus haplotype had p=0.0005). Odds Ratio of SORCS1 in the female subset was 1.7 (p<0.0001). SORCS1 is an interesting candidate gene involved in the Aβ pathway. Therefore, genetic variations in PTPLA and SORCS1 may be associated and have modest effect to the risk of AD by affecting Aβ pathway. The replication of the effect of these genes in different study populations and search for susceptible variants and functional studies of these genes are necessary to get a better understanding of the roles of the genes in Alzheimer disease. PMID:19241460

Amyloid beta peptide immunotherapy in Alzheimer disease.

PubMed

Delrieu, J; Ousset, P J; Voisin, T; Vellas, B

2014-12-01

Recent advances in the understanding of Alzheimer's disease pathogenesis have led to the development of numerous compounds that might modify the disease process. Amyloid β peptide represents an important molecular target for intervention in Alzheimer's disease. The main purpose of this work is to review immunotherapy studies in relation to the Alzheimer's disease. Several types of amyloid β peptide immunotherapy for Alzheimer's disease are under investigation, active immunization and passive administration with monoclonal antibodies directed against amyloid β peptide. Although immunotherapy approaches resulted in clearance of amyloid plaques in patients with Alzheimer's disease, this clearance did not show significant cognitive effect for the moment. Currently, several amyloid β peptide immunotherapy approaches are under investigation but also against tau pathology. Results from amyloid-based immunotherapy studies in clinical trials indicate that intervention appears to be more effective in early stages of amyloid accumulation in particular solanezumab with a potential impact at mild Alzheimer's disease, highlighting the importance of diagnosing Alzheimer's disease as early as possible and undertaking clinical trials at this stage. In both phase III solanezumab and bapineuzumab trials, PET imaging revealed that about a quarter of patients lacked fibrillar amyloid pathology at baseline, suggesting that they did not have Alzheimer's disease in the first place. So a new third phase 3 clinical trial for solanezumab, called Expedition 3, in patients with mild Alzheimer's disease and evidence of amyloid burden has been started. Thus, currently, amyloid intervention is realized at early stage of the Alzheimer's disease in clinical trials, at prodromal Alzheimer's disease, or at asymptomatic subjects or at risk to develop Alzheimer's disease and or at asymptomatic subjects with autosomal dominant mutation. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

The role of ryanodine receptor type 3 in a mouse model of Alzheimer disease

PubMed Central

Liu, Jie; Supnet, Charlene; Sun, Suya; Zhang, Hua; Good, Levi; Popugaeva, Elena; Bezprozvanny, Ilya

2014-01-01

Dysregulated endoplasmic reticulum (ER) calcium (Ca2+) signaling is reported to play an important role in Alzheimer disease (AD) pathogenesis. The role of ER Ca2+ release channels, the ryanodine receptors (RyanRs), has been extensively studied in AD models and RyanR expression and activity are upregulated in the brains of various familial AD (FAD) models. The objective of this study was to utilize a genetic approach to evaluate the importance of RyanR type 3 (RyanR3) in the context of AD pathology. PMID:24476841

Adult onset Niemann-Pick type C disease: A clinical, neuroimaging and molecular genetic study.

PubMed

Battisti, Carla; Tarugi, Patrizla; Dotti, Maria Teresa; De Stefano, Nicola; Vattimo, Angelo; Chierichetti, Francesea; Calandra, Sebastiano; Federico, Antonio

2003-11-01

We report on a patient with adult-onset Niemann-Pick type C (NPC) disease, carrying the mutations P1007 and I1061T in the NPC1 gene, presenting with marked psychiatric changes followed by dystonia and cognitive impairment. Filipin staining, single photon emission computed tomography perfusional, positron emission tomography metabolic, conventional magnetic resonance imaging, and magnetic resonance spectroscopy findings suggested a pathophysiological correlation with phenotype expression. This case expands the clinical and genetic spectrum of the rare adult-onset NPC disease phenotype.

The NACP/synuclein gene: chromosomal assignment and screening for alterations in Alzheimer disease.

PubMed

Campion, D; Martin, C; Heilig, R; Charbonnier, F; Moreau, V; Flaman, J M; Petit, J L; Hannequin, D; Brice, A; Frebourg, T

1995-03-20

The major component of the vascular and plaque amyloid deposits in Alzheimer disease is the amyloid beta peptide (A beta). A second intrinsic component of amyloid, the NAC (non-A beta component of amyloid) peptide, has recently been identified, and its precursor protein was named NACP. A computer homology search allowed us to establish that the human NACP gene was homologous to the rat synuclein gene. We mapped the NACP/synuclein gene to chromosome 4 and cloned three alternatively spliced transcripts in lymphocytes derived from a normal subject. We analyzed by RT-PCR and direct sequencing the entire coding region of the NACP/synuclein gene in a group of patients with familial early onset Alzheimer disease. No mutation was found in 26 unrelated patients. Further studies are required to investigate the implication of the NACP/synuclein gene in Alzheimer disease.

Dynamin 2 gene is a novel susceptibility gene for late-onset Alzheimer disease in non-APOE-epsilon4 carriers.

PubMed

Aidaralieva, Nuripa Jenishbekovna; Kamino, Kouzin; Kimura, Ryo; Yamamoto, Mitsuko; Morihara, Takeshi; Kazui, Hiroaki; Hashimoto, Ryota; Tanaka, Toshihisa; Kudo, Takashi; Kida, Tomoyuki; Okuda, Jun-Ichiro; Uema, Takeshi; Yamagata, Hidehisa; Miki, Tetsuro; Akatsu, Hiroyasu; Kosaka, Kenji; Takeda, Masatoshi

2008-01-01

Alzheimer disease (AD) is characterized by progressive cognitive decline caused by synaptic dysfunction and neurodegeneration in the brain, and late-onset AD (LOAD), genetically classified as a polygenetic disease, is the major form of dementia in the elderly. It has been shown that beta amyloid, deposited in the AD brain, interacts with dynamin 1 and that the dynamin 2 (DNM2) gene homologous to the dynamin 1 gene is encoded at chromosome 19p13.2 where a susceptibility locus has been detected by linkage analysis. To test the genetic association of LOAD with the DNM2 gene, we performed a case-control study of 429 patients with LOAD and 438 sex- and age-matched control subjects in a Japanese population. We found a significant association of LOAD with single nucleotide polymorphism markers of the DNM2 gene, especially in non-carriers of the apolipoprotein E-epsilon4 allele. Even though subjects with the genotype homozygous for the risk allele at rs892086 showed no mutation in exons of the DNM2 gene, expression of DNM2 mRNA in the hippocampus was decreased in the patients compared to non-demented controls. We propose that the DNM2 gene is a novel susceptibility gene for LOAD.

Early-onset dementias: diagnostic and etiological considerations

PubMed Central

2013-01-01

This paper summarizes the body of literature about early-onset dementia (EOD) that led to recommendations from the Fourth Canadian Consensus Conference on the Diagnosis and Treatment of Dementia. A broader differential diagnosis is required for EOD compared with late-onset dementia. Delays in diagnosis are common, and the social impact of EOD requires special care teams. The etiologies underlying EOD syndromes should take into account family history and comorbid diseases, such as cerebrovascular risk factors, that may influence the clinical presentation and age at onset. For example, although many EODs are more likely to have Mendelian genetic and/or metabolic causes, the presence of comorbidities may drive the individual at risk for late-onset dementia to manifest the symptoms at an earlier age, which contributes further to the observed heterogeneity and may confound diagnostic investigation. A personalized medicine approach to diagnosis should therefore be considered depending on the age at onset, clinical presentation, and comorbidities. Genetic counseling and testing as well as specialized biochemical screening are often required, especially in those under the age of 40 and in those with a family history of autosomal dominant or recessive disease. Novel treatments in the drug development pipeline for EOD, such as genetic forms of Alzheimer's disease, should target the specific pathogenic cascade implicated by the mutation or biochemical defect. PMID:24565469

Semantic Memory in the Clinical Progression of Alzheimer Disease.

PubMed

Tchakoute, Christophe T; Sainani, Kristin L; Henderson, Victor W

2017-09-01

Semantic memory measures may be useful in tracking and predicting progression of Alzheimer disease. We investigated relationships among semantic memory tasks and their 1-year predictive value in women with Alzheimer disease. We conducted secondary analyses of a randomized clinical trial of raloxifene in 42 women with late-onset mild-to-moderate Alzheimer disease. We assessed semantic memory with tests of oral confrontation naming, category fluency, semantic recognition and semantic naming, and semantic density in written narrative discourse. We measured global cognition (Alzheimer Disease Assessment Scale, cognitive subscale), dementia severity (Clinical Dementia Rating sum of boxes), and daily function (Activities of Daily Living Inventory) at baseline and 1 year. At baseline and 1 year, most semantic memory scores correlated highly or moderately with each other and with global cognition, dementia severity, and daily function. Semantic memory task performance at 1 year had worsened one-third to one-half standard deviation. Factor analysis of baseline test scores distinguished processes in semantic and lexical retrieval (semantic recognition, semantic naming, confrontation naming) from processes in lexical search (semantic density, category fluency). The semantic-lexical retrieval factor predicted global cognition at 1 year. Considered separately, baseline confrontation naming and category fluency predicted dementia severity, while semantic recognition and a composite of semantic recognition and semantic naming predicted global cognition. No individual semantic memory test predicted daily function. Semantic-lexical retrieval and lexical search may represent distinct aspects of semantic memory. Semantic memory processes are sensitive to cognitive decline and dementia severity in Alzheimer disease.

Biophysical Aspects of Alzheimer's Disease: Implications for Pharmaceutical Sciences : Theme: Drug Discovery, Development and Delivery in Alzheimer's Disease Guest Editor: Davide Brambilla.

PubMed

Arosio, Paolo

2017-12-01

An increasing amount of findings suggests that the aggregation of soluble peptides and proteins into amyloid fibrils is a relevant upstream process in the complex cascade of events leading to the pathology of Alzheimer's disease and several other neurodegenerative disorders. Nevertheless, several aspects of the correlation between the aggregation process and the onset and development of the pathology remain largely elusive. In this context, biophysical and biochemical studies in test tubes have proven extremely powerful in providing quantitative information about the structure and the reactivity of amyloids at the molecular level. In this review we use selected recent examples to illustrate the importance of such biophysical research to complement phenomenological studies based on cellular and molecular biology, and we discuss the implications for pharmaceutical applications associated with Alzheimer's disease and other neurodegenerative disorders in both academic and industrial contexts.

Generalized onset seizures with focal evolution (GOFE) - A unique seizure type in the setting of generalized epilepsy.

PubMed

Linane, Avriel; Lagrange, Andre H; Fu, Cary; Abou-Khalil, Bassel

2016-01-01

We report clinical and electrographic features of generalized onset seizures with focal evolution (GOFE) and present arguments for the inclusion of this seizure type in the seizure classification. The adult and pediatric Epilepsy Monitoring Unit databases at Vanderbilt Medical Center and Children's Hospital were screened to identify generalized onset seizures with focal evolution. We reviewed medical records for epilepsy characteristics, epilepsy risk factors, MRI abnormalities, neurologic examination, antiepileptic medications before and after diagnosis, and response to medications. We also reviewed ictal and interictal EEG tracings, as well as video-recorded semiology. Ten patients were identified, 7 males and 3 females. All of the patients developed generalized epilepsy in childhood or adolescence (ages 3-15years). Generalized onset seizures with focal evolution developed years after onset in 9 patients, with a semiology concerning for focal seizures or nonepileptic events. Ictal discharges had a generalized onset on EEG, described as either generalized spike-and-wave and/or polyspike-and-wave discharges, or generalized fast activity. This electrographic activity then evolved to focal rhythmic activity most commonly localized to one temporal or frontal region; five patients had multiple seizures evolving to focal activity in different regions of both hemispheres. The predominant interictal epileptiform activity included generalized spike-and-wave and/or polyspike-and-wave discharges in all patients. Taking into consideration all clinical and EEG data, six patients were classified with genetic (idiopathic) generalized epilepsy, and four were classified with structural/metabolic (symptomatic) generalized epilepsy. All of the patients had modifications to their medications following discharge, with three becoming seizure-free and five responding with >50% reduction in seizure frequency. Generalized onset seizures may occasionally have focal evolution with semiology

A comparison of two different approaches to characterizing the heterogeneity within antisocial behavior: age-of-onset versus behavioral sub-types.

PubMed

Burt, S Alexandra; Hopwood, Christopher J

2010-04-01

There are two common approaches to sub-typing the well-documented heterogeneity within antisocial behavior: age-of-onset (i.e., child-onset versus adolescent-onset; see Moffitt, 1993) and behavioral (i.e., physical aggression versus nonaggressive rule-breaking). These approaches appear to be intimately connected, such that aggression is particularly characteristic of child-onset antisocial behavior whereas rule-breaking is largely specific to adolescent-onset antisocial behavior (see Moffitt, 2003). Even so, it remains unclear which approach, if either, substantively drives these different manifestations of antisocial behavior. We examined this question in a sample of 1,726 adults in treatment for alcoholism, evaluating the two approaches in regards to their prediction of anger and alcohol dependency. Although age-of-onset predicted both outcomes when analyzed alone, these associations fully dissipated once we controlled for aggression and rule-breaking. Such findings suggest that the behavioral sub-types may prove to be a stronger predictor of antisocial behavior outcomes than is age-of-onset.

Lifestyle Factors and Alzheimer's Disease in People with Down Syndrome

ERIC Educational Resources Information Center

Kenshole, Athena V.; Gallichan, Deanna; Pahl, Sabine; Clibbens, John

2017-01-01

Background: Lifestyle has previously been associated with the onset of Alzheimer's disease (AD) in the typically developing population, but research investigating this association in Down syndrome (DS) is limited. Method: Adults with DS and AD (n = 27) were compared to adults with DS without AD (n = 30) on physical activity, diet, weight, where…

Ron Hays: A Story of Art as Self Treatment for Alzheimer's Disease

ERIC Educational Resources Information Center

Jones, Robin M. N.; Hays, Nancy Scheller

2016-01-01

Ronald E. Hays is the former Director of the Hahnemann Creative Arts in Therapy Department at Drexel University in Philadelphia, Pennsylvania, and the cofounder of the graduate art therapy program at Eastern Virginia Medical School in Norfolk, Virginia. At the age of 62 he was diagnosed with early onset Alzheimer's disease, a form of dementia. In…

Alzheimer's neurofibrillary pathology and the spectrum of cognitive function: findings from the Nun Study.

PubMed

Riley, Kathryn P; Snowdon, David A; Markesbery, William R

2002-05-01

The development of interventions designed to delay the onset of dementia highlights the need to determine the neuropathologic characteristics of individuals whose cognitive function ranges from intact to demented, including those with mild cognitive impairments. We used the Braak method of staging Alzheimer's disease pathology in 130 women ages 76-102 years who were participants in the Nun Study, a longitudinal study of aging and Alzheimer's disease. All participants had complete autopsy data and were free from neuropathologic conditions other than Alzheimer's disease lesions that could affect cognitive function. Findings showed a strong relationship between Braak stage and cognitive state. The presence of memory impairment was associated with more severe Alzheimer's disease pathology and higher incidence of conversion to dementia in the groups classified as having mild or global cognitive impairments. In addition to Braak stage, atrophy of the neocortex was significantly related to the presence of dementia. Our data indicate that Alzheimer's neurofibrillary pathology is one of the neuropathologic substrates of mild cognitive impairments. Additional studies are needed to help explain the variability in neuropathologic findings seen in individuals whose cognitive performance falls between intact function and dementia.

Kidney Disease and Youth Onset Type 2 Diabetes: Considerations for the General Practitioner

PubMed Central

Dart, Allison B.; Sellers, Elizabeth A.; Dean, Heather J.

2012-01-01

Youth onset type 2 diabetes (T2DM) continues to increase worldwide, concomitant with the rising obesity epidemic. There is evidence to suggest that youth with T2DM are affected by the same comorbidities and complications as adults diagnosed with T2DM. This review highlights specifically the kidney disease associated with youth onset T2DM, which is highly prevalent and associated with a high risk of end-stage kidney disease in early adulthood. A general understanding of this complex disease by primary care providers is critical, so that at-risk individuals are identified and managed early in the course of their disease, such that progression can be modified in this high-risk group of children and adolescents. A review of the pediatric literature will include a focus on the epidemiology, risk factors, pathology, screening, and treatment of kidney disease in youth onset T2DM. PMID:22315622

Methods for detecting additional genes underlying Alzheimer disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Locke, P.A.; Haines, J.L.; Ter-Minassian, M.

1994-09-01

Alzheimer`s disease (AD) is a complex inherited disorder with proven genetic heterogeneity. To date, genes on chromosome 21 (APP) and 14 (not yet identified) are associated with early-onset familial AD, while the APOE gene on chromosome 19 is associated with both late onset familial and sporadic AD and early onset sporadic AD. Although these genes likely account for the majority of AD, many familial cases cannot be traced to any of these genes. From a set of 127 late-onset multiplex families screened for APOE, 43 (34%) families have at least one affected individual with no APOE-4 allele, suggesting an alternativemore » genetic etiology. Simulation studies indicated that additional loci could be identified through a genomic screen with a 10 cM sieve on a subset of 21 well documented, non-APOE-4 families. Given the uncertainties in the mode of inheritance, reliance on a single analytical method could result in a missed linkage. Therefore, we have developed a strategy of using multiple overlapping yet complementary methods to detect linkage. These include sib-pair analysis and affected-pedigree-member analysis, neither of which makes assumptions about mode of inheritance, and lod score analysis (using two predefined genetic models). In order for a marker to qualify for follow-up, it must fit at least two of three criteria. These are nominal P values of 0.05 or less for the non-parametric methods, and/or a lod score greater than 1.0. Adjacent markers each fulfilling a single criterion also warrant follow-up. To date, we have screened 61 markers on chromosomes 1, 2, 3, 18, 19, 21, and 22. One marker, D2S163, generated a lod score of 1.06 ({theta} = 0.15) and an APMT statistic of 3.68 (P < 0.001). This region is currently being investigated in more detail. Updated results of this region plus additional screening data will be presented.« less

Clinicopathological concordance and discordance in three monozygotic twin pairs with familial Alzheimer's disease

PubMed Central

Brickell, Kiri L; Leverenz, James B; Steinbart, Ellen J; Rumbaugh, Malia; Schellenberg, Gerard D; Nochlin, David; Lampe, Thomas H; Holm, Ida E; Van Deerlin, Vivianna; Yuan, Wuxing; Bird, Thomas D

2007-01-01

Aim Neuropathological examination of both individuals in a monozygotic (MZ) twin pair with Alzheimer's disease (AD) is rare, especially in the molecular genetic era. We had the opportunity to assess the concordance and discordance of clinical presentation and neuropathology in three MZ twin pairs with AD. Methods The MZ twins were identified and characterised by the University of Washington Alzheimer's Disease Research Center. We reviewed the available clinical and neuropathological records for all six cases looking specifically for concordance and discordance of clinical phenotype, neuritic amyloid plaques (NP), neurofibrillary tangles (NFT) and Lewy related pathology (LRP). Results Discordance in age of onset for developing AD in the MZ twins varied from 4 to 18 years. Clinical presentations also differed between twins. One twin presented with a dementia with Lewy Body clinical syndrome while the other presented with typical clinical AD. Neuropathology within the MZ twin pairs was concordant for NP and NFT, regardless of duration of disease, and was discordant for LRP. This difference was most marked in the late onset AD twin pair. One pair was found to have a mutation in presenilin‐1 (PS1) (A79V) with remarkably late onset in a family member. Conclusions MZ twins with AD can vary considerably in age of onset, presentation and disease duration. The concordance of NP and NFT pathological change and the discordance of LRP support the concept that, in AD, the former are primarily under genetic control whereas the latter (LRP) is more influenced by disease duration and environmental factors. The A79V mutation in PS1 can be associated with very late onset of dementia. PMID:17615170

Exploring single nucleotide polymorphisms previously related to obesity and metabolic traits in pediatric-onset type 2 diabetes.

PubMed

Miranda-Lora, América Liliana; Cruz, Miguel; Aguirre-Hernández, Jesús; Molina-Díaz, Mario; Gutiérrez, Jorge; Flores-Huerta, Samuel; Klünder-Klünder, Miguel

2017-07-01

To evaluate the association of 64 obesity-related polymorphisms with pediatric-onset type 2 diabetes and other glucose- and insulin-related traits in Mexican children. Case-control and case-sibling designs were followed. We studied 99 patients with pediatric-onset type 2 diabetes, their siblings (n = 101) without diabetes, 83 unrelated pediatric controls and 137 adult controls. Genotypes were determined for 64 single nucleotide polymorphisms, and a possible association was examined between those genotypes and type 2 diabetes and other quantitative traits, after adjusting for age, sex and body mass index. In the case-pediatric control and case-adult control analyses, five polymorphisms were associated with increased likelihood of pediatric-onset type 2 diabetes; only one of these polymorphisms (CADM2/rs1307880) also showed a consistent effect in the case-sibling analysis. The associations in the combined analysis were as follows: ADORA1/rs903361 (OR 1.9, 95% CI 1.2; 3.0); CADM2/rs13078807 (OR 2.2, 95% CI 1.2; 4.0); GNPDA2/rs10938397 (OR 2.2, 95% CI 1.4; 3.7); VEGFA/rs6905288 (OR 1.4, 95% CI 1.1; 2.1) and FTO/rs9939609 (OR 1.8, 95% CI 1.0; 3.2). We also identified 16 polymorphisms nominally associated with quantitative traits in participants without diabetes. ADORA/rs903361, CADM2/rs13078807, GNPDA2/rs10938397, VEGFA/rs6905288 and FTO/rs9939609 are associated with an increased risk of pediatric-onset type 2 diabetes in the Mexican population.

Platelets, lymphocytes and erythrocytes from Alzheimer's disease patients: the quest for blood cell-based biomarkers.

PubMed

Pluta, Ryszard; Ułamek-Kozioł, Marzena; Januszewski, Sławomir; Czuczwar, Stanisław J

2018-01-01

In elderly population, Alzheimer's disease is a common neurodegenerative disorder and accounts for about 70% of all cases of dementia. The neurodegenerative processes of this disease start presumably 20 years ahead of the clinical beginning of the disorder. The postmortem histopathological examination, brains from Alzheimer's disease patients with characteristic features like amyloid plaques and neurofibrillary tangles, neuronal and synaptic disintegration confirm the final diagnosis of Alzheimer's disease. Senile plaques are composed of -amyloid peptide, deriving from the amyloid protein precursor, which is present not only in the brain tissue, but also in other non-neuronal tissues. Some investigations reported that platelets possess amyloid protein precursor and all the enzymatic activities required for the metabolism of this protein throughout the same pathways present in the brain. Thus, platelets may be a good peripheral blood cell-based biomarker to study the onset of Alzheimer's disease. Another line of research indicated molecular and cellular aberrations in blood lymphocytes and erythrocytes from Alzheimer's disease patients and emphasizes the systemic nature of the disease. In this review, we will summarize the recent knowledge on the involvement and/or response of platelets, lymphocytes and red blood cells in the circulation during Alzheimer's disease development. The facts will be reviewed with the special possibility for applying the above blood cells as Alzheimer's disease preclinical and antemortem blood cell-based biomarkers.

Transethnic genome-wide scan identifies novel Alzheimer's disease loci.

PubMed

Jun, Gyungah R; Chung, Jaeyoon; Mez, Jesse; Barber, Robert; Beecham, Gary W; Bennett, David A; Buxbaum, Joseph D; Byrd, Goldie S; Carrasquillo, Minerva M; Crane, Paul K; Cruchaga, Carlos; De Jager, Philip; Ertekin-Taner, Nilufer; Evans, Denis; Fallin, M Danielle; Foroud, Tatiana M; Friedland, Robert P; Goate, Alison M; Graff-Radford, Neill R; Hendrie, Hugh; Hall, Kathleen S; Hamilton-Nelson, Kara L; Inzelberg, Rivka; Kamboh, M Ilyas; Kauwe, John S K; Kukull, Walter A; Kunkle, Brian W; Kuwano, Ryozo; Larson, Eric B; Logue, Mark W; Manly, Jennifer J; Martin, Eden R; Montine, Thomas J; Mukherjee, Shubhabrata; Naj, Adam; Reiman, Eric M; Reitz, Christiane; Sherva, Richard; St George-Hyslop, Peter H; Thornton, Timothy; Younkin, Steven G; Vardarajan, Badri N; Wang, Li-San; Wendlund, Jens R; Winslow, Ashley R; Haines, Jonathan; Mayeux, Richard; Pericak-Vance, Margaret A; Schellenberg, Gerard; Lunetta, Kathryn L; Farrer, Lindsay A

2017-07-01

Genetic loci for Alzheimer's disease (AD) have been identified in whites of European ancestry, but the genetic architecture of AD among other populations is less understood. We conducted a transethnic genome-wide association study (GWAS) for late-onset AD in Stage 1 sample including whites of European Ancestry, African-Americans, Japanese, and Israeli-Arabs assembled by the Alzheimer's Disease Genetics Consortium. Suggestive results from Stage 1 from novel loci were followed up using summarized results in the International Genomics Alzheimer's Project GWAS dataset. Genome-wide significant (GWS) associations in single-nucleotide polymorphism (SNP)-based tests (P < 5 × 10 -8 ) were identified for SNPs in PFDN1/HBEGF, USP6NL/ECHDC3, and BZRAP1-AS1 and for the interaction of the (apolipoprotein E) APOE ε4 allele with NFIC SNP. We also obtained GWS evidence (P < 2.7 × 10 -6 ) for gene-based association in the total sample with a novel locus, TPBG (P = 1.8 × 10 -6 ). Our findings highlight the value of transethnic studies for identifying novel AD susceptibility loci. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Seizures and epilepsy in Alzheimer's disease.

PubMed

Friedman, Daniel; Honig, Lawrence S; Scarmeas, Nikolaos

2012-04-01

Many studies have shown that patients with Alzheimer's disease (AD) are at increased risk for developing seizures and epilepsy. However, reported prevalence and incidence of seizures and relationship of seizures to disease measures such as severity, outcome, and progression vary widely between studies. We performed a literature review of the available clinical and epidemiological data on the topic of seizures in patients with AD. We review seizure rates and types, risk factors for seizures, electroencephalogram (EEG) studies, and treatment responses. Finally, we consider limitations and methodological issues. There is considerable variability in the reported prevalence and incidence of seizures in patients with AD-with reported lifetime prevalence rates of 1.5-64%. More recent, prospective, and larger studies in general report lower rates. Some, but not all, studies have noted increased seizure risk with increasing dementia severity or with younger age of AD onset. Generalized convulsive seizures are the most commonly reported type, but often historical information is the only basis used to determine seizure type and the manifestation of seizures may be difficult to distinguish from other behaviors common in demented patients. EEG has infrequently been performed and reported. Data on treatment of seizures in AD are extremely limited. Similarly, the relationship between seizures and cognitive impairment in AD is unclear. We conclude that the literature on seizures and epilepsy in AD, including diagnosis, risk factors, and response to treatment suffers from methodological limitations and gaps. © 2011 Blackwell Publishing Ltd.

ApoE Genotype and Alzheimer's Disease in Adults with Down Syndrome: Meta-Analysis.

ERIC Educational Resources Information Center

Prashner, V. P.; Chowdhury, T. A.; Rowe, B. R.; Bain, S. C.

1997-01-01

ApoE gene polymorphism was examined in 100 adults with Down syndrome with and without dementia (Alzheimer's disease) and 346 control subjects. Additionally, a meta analysis of studies (total N=480 subjects) was performed. Results indicated a similar incidence of the gene across groups but subjects with the allele tended to an earlier onset of…

The NACP/synuclein gene: Chromosomal assignment and screening for alterations in Alzheimer disease

DOE Office of Scientific and Technical Information (OSTI.GOV)

Campion, D.; Martin, C.; Charbonnier, F.

1995-03-20

The major component of the vascular and plaque amyloid deposits in Alzheimer disease is the amyloid {beta} peptide (A{beta}). A second intrinsic component of amyloid, the NAC (non-A{beta} component of amyloid) peptide, has recently been identified, and its precursor protein was named NACP. A computer homology search allowed us to establish that the human NACP gene was homologous to the rat synuclein gene. We mapped the NACP/synuclein gene to chromosome 4 and cloned three alternatively spliced transcripts in lymphocytes derived from a normal subject. We analyzed by RT-PCR and direct sequencing the entire coding region of the NACP/synuclein gene inmore » a group of patients with familial early onset Alzheimer disease. No mutation was found in 26 unrelated patients. Further studies are required to investigate the implication of the NACP/synuclein gene in Alzheimer disease. 21 refs., 3 tabs.« less

Cognitive Decline in a Colombian Kindred With Autosomal Dominant Alzheimer Disease

PubMed Central

Aguirre-Acevedo, Daniel C.; Lopera, Francisco; Henao, Eliana; Tirado, Victoria; Muñoz, Claudia; Giraldo, Margarita; Bangdiwala, Shrikant I.; Reiman, Eric M.; Tariot, Pierre N.; Langbaum, Jessica B.; Quiroz, Yakeel T.; Jaimes, Fabian

2017-01-01

IMPORTANCE Data from an autosomal dominant Alzheimer disease (ADAD) kindred were used to track the longitudinal trajectory of cognitive decline associated with preclinical ADAD and explore factors that may modify the rate of cognitive decline. OBJECTIVES To evaluate the onset and rate of cognitive decline during preclinical ADAD and the effect of socioeconomic, vascular, and genetic factors on the cognitive decline. DESIGN, SETTING, AND PARTICIPANTS We performed a retrospective cohort study from January 1, 1995, through June 31, 2012, of individuals from Antioquia, Colombia, who tested positive for the ADAD-associated PSEN1 E280A mutation. Data analysis was performed from August 20, 2014, through November 30, 2015. A mixed-effects model was used to estimate annual rates of change in cognitive test scores and to mark the onset of cognitive decline. MAIN OUTCOMES AND MEASURES Memory, language, praxis, and total scores from the Consortium to Establish a Registry for Alzheimer Disease test battery. Chronologic age was used as a time scale in the models. We explore the effects of sex; educational level; socioeconomic status; residence area; occupation type; marital status; history of hypertension, diabetes mellitus, and dyslipidemia; tobacco and alcohol use; and APOE ε4 on the rates of cognitive decline. RESULTS A total of 493 carriers met the inclusion criteria and were analyzed. A total of 256 carriers had 2 or more assessments. At the time of the initial assessment, participants had a mean (SD) age of 33.4 (11.7) years and a mean (SD) educational level of 7.2 (4.2) years. They were predominantly female (270 [54.8%]), married (293 [59.4%]), and of low socioeconomic status (322 [65.3%]). Word list recall scores provided the earliest indicator of preclinical cognitive decline at 32 years of age, 12 and 17 years before the kindred’s respective median ages at mild cognitive impairment and dementia onset. After the change point, carriers had a statistically significant

Stability of Iowa mutant and wild type Aβ-peptide aggregates

NASA Astrophysics Data System (ADS)

Alred, Erik J.; Scheele, Emily G.; Berhanu, Workalemahu M.; Hansmann, Ulrich H. E.

2014-11-01

Recent experiments indicate a connection between the structure of amyloid aggregates and their cytotoxicity as related to neurodegenerative diseases. Of particular interest is the Iowa Mutant, which causes early-onset of Alzheimer's disease. While wild-type Amyloid β-peptides form only parallel beta-sheet aggregates, the mutant also forms meta-stable antiparallel beta sheets. Since these structural variations may cause the difference in the pathological effects of the two Aβ-peptides, we have studied in silico the relative stability of the wild type and Iowa mutant in both parallel and antiparallel forms. We compare regular molecular dynamics simulations with such where the viscosity of the samples is reduced, which, we show, leads to higher sampling efficiency. By analyzing and comparing these four sets of all-atom molecular dynamics simulations, we probe the role of the various factors that could lead to the structural differences. Our analysis indicates that the parallel forms of both wild type and Iowa mutant aggregates are stable, while the antiparallel aggregates are meta-stable for the Iowa mutant and not stable for the wild type. The differences result from the direct alignment of hydrophobic interactions in the in-register parallel oligomers, making them more stable than the antiparallel aggregates. The slightly higher thermodynamic stability of the Iowa mutant fibril-like oligomers in its parallel organization over that in antiparallel form is supported by previous experimental measurements showing slow inter-conversion of antiparallel aggregates into parallel ones. Knowledge of the mechanism that selects between parallel and antiparallel conformations and determines their relative stability may open new avenues for the development of therapies targeting familial forms of early-onset Alzheimer's disease.

Subjective memory complaints in preclinical autosomal dominant Alzheimer disease.

PubMed

Norton, Daniel J; Amariglio, Rebecca; Protas, Hillary; Chen, Kewei; Aguirre-Acevedo, Daniel C; Pulsifer, Brendan; Castrillon, Gabriel; Tirado, Victoria; Munoz, Claudia; Tariot, Pierre; Langbaum, Jessica B; Reiman, Eric M; Lopera, Francisco; Sperling, Reisa A; Quiroz, Yakeel T

2017-10-03

To cross-sectionally study subjective memory complaints (SMC) in autosomal dominant Alzheimer disease (ADAD). We examined self-reported and study partner-based SMC in 52 young, cognitively unimpaired individuals from a Colombian kindred with early-onset ADAD. Twenty-six carried the PSEN-1 E280A mutation, averaging 7 years of age younger than the kindred's expected clinical onset. Twenty-six were age-matched noncarriers. Participants also underwent structural MRI and cognitive testing. Self-reported SMC were greater in carriers than noncarriers ( p = 0.02). Study partner-based SMC did not differ between groups ( p = 0.21), but in carriers increased with age ( r = 0.66, p < 0.001) and decreased with hippocampal volume ( r = -0.35, p = 0.08). Cognitively unimpaired PSEN-1 carriers have elevated SMC. Self-reported SMC may be a relatively early indicator of preclinical AD, while partner- reported SMC increases later in preclinical AD, closer to clinical onset. © 2017 American Academy of Neurology.

2016 Alzheimer's disease facts and figures.

PubMed

2016-04-01

beneficiaries without these conditions, and Medicaid payments are 19 times as great. Total payments in 2016 for health care, long-term care and hospice services for people age ≥ 65 years with dementia are estimated to be $236 billion. The costs of Alzheimer's care may place a substantial financial burden on families, who often have to take money out of their retirement savings, cut back on buying food, and reduce their own trips to the doctor. In addition, many family members incorrectly believe that Medicare pays for nursing home care and other types of long-term care. Such findings highlight the need for solutions to prevent dementia-related costs from jeopardizing the health and financial security of the families of people with Alzheimer's and other dementias.

Discrimination between Alzheimer's Disease and Late Onset Bipolar Disorder Using Multivariate Analysis.

PubMed

Besga, Ariadna; Gonzalez, Itxaso; Echeburua, Enrique; Savio, Alexandre; Ayerdi, Borja; Chyzhyk, Darya; Madrigal, Jose L M; Leza, Juan C; Graña, Manuel; Gonzalez-Pinto, Ana Maria

2015-01-01

Late onset bipolar disorder (LOBD) is often difficult to distinguish from degenerative dementias, such as Alzheimer disease (AD), due to comorbidities and common cognitive symptoms. Moreover, LOBD prevalence in the elder population is not negligible and it is increasing. Both pathologies share pathophysiological neuroinflammation features. Improvements in differential diagnosis of LOBD and AD will help to select the best personalized treatment. The aim of this study is to assess the relative significance of clinical observations, neuropsychological tests, and specific blood plasma biomarkers (inflammatory and neurotrophic), separately and combined, in the differential diagnosis of LOBD versus AD. It was carried out evaluating the accuracy achieved by classification-based computer-aided diagnosis (CAD) systems based on these variables. A sample of healthy controls (HC) (n = 26), AD patients (n = 37), and LOBD patients (n = 32) was recruited at the Alava University Hospital. Clinical observations, neuropsychological tests, and plasma biomarkers were measured at recruitment time. We applied multivariate machine learning classification methods to discriminate subjects from HC, AD, and LOBD populations in the study. We analyzed, for each classification contrast, feature sets combining clinical observations, neuropsychological measures, and biological markers, including inflammation biomarkers. Furthermore, we analyzed reduced feature sets containing variables with significative differences determined by a Welch's t-test. Furthermore, a battery of classifier architectures were applied, encompassing linear and non-linear Support Vector Machines (SVM), Random Forests (RF), Classification and regression trees (CART), and their performance was evaluated in a leave-one-out (LOO) cross-validation scheme. Post hoc analysis of Gini index in CART classifiers provided a measure of each variable importance. Welch's t-test found one biomarker (Malondialdehyde) with

A genomewide screen for late-onset Alzheimer disease in a genetically isolated Dutch population.

PubMed

Liu, Fan; Arias-Vásquez, Alejandro; Sleegers, Kristel; Aulchenko, Yurii S; Kayser, Manfred; Sanchez-Juan, Pascual; Feng, Bing-Jian; Bertoli-Avella, Aida M; van Swieten, John; Axenovich, Tatiana I; Heutink, Peter; van Broeckhoven, Christine; Oostra, Ben A; van Duijn, Cornelia M

2007-07-01

Alzheimer disease (AD) is the most common cause of dementia. We conducted a genome screen of 103 patients with late-onset AD who were ascertained as part of the Genetic Research in Isolated Populations (GRIP) program that is conducted in a recently isolated population from the southwestern area of The Netherlands. All patients and their 170 closely related relatives were genotyped using 402 microsatellite markers. Extensive genealogy information was collected, which resulted in an extremely large and complex pedigree of 4,645 members. The pedigree was split into 35 subpedigrees, to reduce the computational burden of linkage analysis. Simulations aiming to evaluate the effect of pedigree splitting on false-positive probabilities showed that a LOD score of 3.64 corresponds to 5% genomewide type I error. Multipoint analysis revealed four significant and one suggestive linkage peaks. The strongest evidence of linkage was found for chromosome 1q21 (heterogeneity LOD [HLOD]=5.20 at marker D1S498). Approximately 30 cM upstream of this locus, we found another peak at 1q25 (HLOD=4.0 at marker D1S218). These two loci are in a previously established linkage region. We also confirmed the AD locus at 10q22-24 (HLOD=4.15 at marker D10S185). There was significant evidence of linkage of AD to chromosome 3q22-24 (HLOD=4.44 at marker D3S1569). For chromosome 11q24-25, there was suggestive evidence of linkage (HLOD=3.29 at marker D11S1320). We next tested for association between cognitive function and 4,173 single-nucleotide polymorphisms in the linked regions in an independent sample consisting of 197 individuals from the GRIP region. After adjusting for multiple testing, we were able to detect significant associations for cognitive function in four of five AD-linked regions, including the new region on chromosome 3q22-24 and regions 1q25, 10q22-24, and 11q25. With use of cognitive function as an endophenotype of AD, our study indicates the that the RGSL2, RALGPS2, and C1orf49 genes

Social Network Data Validity: The Example of the Social Network of Caregivers of Older Persons with Alzheimer-Type Dementia

ERIC Educational Resources Information Center

Carpentier, Normand

2007-01-01

This article offers reflection on the validity of relational data such as used in social network analysis. Ongoing research on the transformation of the support network of caregivers of persons with an Alzheimer-type disease provides the data to fuel the debate on the validity of participant report. More specifically, we sought to understand the…

Habitual coffee consumption and risk of type 2 diabetes, ischemic heart disease, depression and Alzheimer's disease: a Mendelian randomization study.

PubMed

Kwok, Man Ki; Leung, Gabriel M; Schooling, C Mary

2016-11-15

Observationally, coffee is inversely associated with type 2 diabetes mellitus (T2DM), depression and Alzheimer's disease, but not ischemic heart disease (IHD). Coffee features as possibly protective in the 2015 Dietary Guidelines for Americans. Short-term trials suggest coffee has neutral effect on most glycemic traits, but raises lipids and adiponectin. To clarify we compared T2DM, depression, Alzheimer's disease, and IHD and its risk factors by genetically predicted coffee consumption using two-sample Mendelian randomization applied to large extensively genotyped case-control and cross-sectional studies. Childhood cognition was used as a negative control outcome. Genetically predicted coffee consumption was not associated with T2DM (odds ratio (OR) 1.02, 95% confidence interval (CI) 0.76 to 1.36), depression (0.89, 95% CI 0.66 to 1.21), Alzheimer's disease (1.17, 95% CI 0.96 to 1.43), IHD (0.96, 95% CI 0.80 to 1.14), lipids, glycemic traits, adiposity or adiponectin. Coffee was unrelated to childhood cognition. Consistent with observational studies, coffee was unrelated to IHD, and, as expected, childhood cognition. However, contrary to observational findings, coffee may not have beneficial effects on T2DM, depression or Alzheimer's disease. These findings clarify the role of coffee with relevance to dietary guidelines and suggest interventions to prevent these complex chronic diseases should be sought elsewhere.

Does APO ε4 correlate with MRI changes in Alzheimer's disease?

PubMed Central

Doody, R; Azher, S; Haykal, H; Dunn, J; Liao, T; Schneider, L

2000-01-01

OBJECTIVE—To assess the relation between APO E genotype and MRI white matter changes in Alzheimer's disease. The APO ε4 allele is correlated with amyloid angiopathy and other neuropathologies in Alzheimer's disease and could be associated with white matter changes. If so, there should be a dose effect.
METHODS—104 patients with probable Alzheimer's disease (NINCDS-ADRDA criteria) in this Alzheimer's Disease Research Centre were studied. Patients received MRI and APO E genotyping by standardised protocols. Axial MRI was scored (modified Schelten's scale) for the presence and degree of white matter changes and atrophy in several regions by a neuroradiologist blinded to genotype. Total white matter and total atrophy scores were also generated. Data analysis included Pearson's correlation for regional and total imaging scores and analysis of variance (ANOVA) (or Kruskal-Wallis) and χ2 for demographic and disease related variables.
RESULTS—30 patients had no ε4, 53 patients were heterozygous, and 21 patients were homozygous. The three groups did not differ in sex distribution, age of onset, age at MRI, MMSE, clinical dementia rating, or modified Hachinski ischaemia scores. There were no significant correlations between total or regional white matter scores and APO E genotype (Pearson correlation).
CONCLUSIONS—No correlation between total or regional white matter scores and APO E genotype was found. The pathogenesis of white matter changes in Alzheimer's disease may be independent of APO E genotype.

 PMID:11032626

Evidence for brain glucose dysregulation in Alzheimer's disease.

PubMed

An, Yang; Varma, Vijay R; Varma, Sudhir; Casanova, Ramon; Dammer, Eric; Pletnikova, Olga; Chia, Chee W; Egan, Josephine M; Ferrucci, Luigi; Troncoso, Juan; Levey, Allan I; Lah, James; Seyfried, Nicholas T; Legido-Quigley, Cristina; O'Brien, Richard; Thambisetty, Madhav

2018-03-01

It is unclear whether abnormalities in brain glucose homeostasis are associated with Alzheimer's disease (AD) pathogenesis. Within the autopsy cohort of the Baltimore Longitudinal Study of Aging, we measured brain glucose concentration and assessed the ratios of the glycolytic amino acids, serine, glycine, and alanine to glucose. We also quantified protein levels of the neuronal (GLUT3) and astrocytic (GLUT1) glucose transporters. Finally, we assessed the relationships between plasma glucose measured before death and brain tissue glucose. Higher brain tissue glucose concentration, reduced glycolytic flux, and lower GLUT3 are related to severity of AD pathology and the expression of AD symptoms. Longitudinal increases in fasting plasma glucose levels are associated with higher brain tissue glucose concentrations. Impaired glucose metabolism due to reduced glycolytic flux may be intrinsic to AD pathogenesis. Abnormalities in brain glucose homeostasis may begin several years before the onset of clinical symptoms. Copyright © 2017 the Alzheimer's Association. All rights reserved.

Very low density lipoprotein receptor in Alzheimer disease.

PubMed

Helbecque, N; Amouyel, P

2000-08-15

The apolipoprotein (APO) E4 isoform is associated with an accelerated rate of Alzheimer disease (AD) expression in sporadic as well as late-onset familial forms of the disease but the precise mechanism is unknown. In an attempt to approach the possible mechanisms involved, APOE receptors have been studied. They all belong to the low density lipoprotein (LDL) receptor family and share the same structural motifs. Some of them are preferentially expressed in the brain such as the LDL receptor related protein, the apolipoprotein E receptor 2, and the very low density lipoprotein (VLDL) receptor. These receptors have been suspected to be involved in Alzheimer disease at various levels. Among them, the VLDL receptor was extensively explored. Although genetic studies conducted on a polymorphism in the promoter of the VLDL receptor in Japanese and Caucasian populations gave divergent results, this does not exclude a possible involvement of the VLDL receptor in AD. Copyright 2000 Wiley-Liss, Inc.

The Role of Cardiovascular Risk Factors and Stroke in Familial Alzheimer Disease.

PubMed

Tosto, Giuseppe; Bird, Thomas D; Bennett, David A; Boeve, Bradley F; Brickman, Adam M; Cruchaga, Carlos; Faber, Kelley; Foroud, Tatiana M; Farlow, Martin; Goate, Alison M; Graff-Radford, Neill R; Lantigua, Rafael; Manly, Jennifer; Ottman, Ruth; Rosenberg, Roger; Schaid, Daniel J; Schupf, Nicole; Stern, Yaakov; Sweet, Robert A; Mayeux, Richard

2016-10-01

The contribution of cardiovascular disease (CV) and cerebrovascular disease to the risk for late-onset Alzheimer disease (LOAD) has been long debated. Investigations have shown that antecedent CV risk factors increase the risk for LOAD, although other investigations have failed to validate this association. To study the contribution of CV risk factors (type 2 diabetes, hypertension, and heart disease) and the history of stroke to LOAD in a data set of large families multiply affected by LOAD. The National Institute on Aging Late-Onset Alzheimer Disease/National Cell Repository for Alzheimer Disease family study (hereinafter referred to as NIA-LOAD study) is a longitudinal study of families with multiple members affected with LOAD. A multiethnic community-based longitudinal study (Washington Heights-Inwood Columbia Aging Project [WHICAP]) was used to replicate findings. The 6553 participants in the NIA-LOAD study were recruited from 23 US Alzheimer disease centers with ongoing data collection since 2003; the 5972 WHICAP participants were recruited at Columbia University with ongoing data collection since 1992. Data analysis was performed from 2003 to 2015. Generalized mixed logistic regression models tested the association of CV risk factors (primary association) with LOAD. History of stroke was used for the secondary association. A secondary model adjusted for the presence of an apolipoprotein E (APOE) ε4 allele. A genetic risk score, based on common variants associated with LOAD, was used to account for LOAD genetic risk beyond the APOE ε4 effect. Mediation analyses evaluated stroke as a mediating factor between the primary association and LOAD. A total of 6553 NIA-LOAD participants were included in the analyses (4044 women [61.7%]; 2509 men [38.3%]; mean [SD] age, 77.0 [9] years), with 5972 individuals from the WHICAP study included in the replication sample (4072 women [68.2%]; 1900 men [31.8%]; mean [SD] age, 76.5 [7.0] years). Hypertension was associated

Multiple etiologies for Alzheimer disease are revealed by segregation analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rao, V.S.; Connor-Lacke, L.; Cupplies, L.A.

1994-11-01

We have evaluated several transmission models for Alzheimer disease (AD), using the logistic regressive approach in 401 nuclear families of consecutively ascertained and rigorously diagnosed probands. Models postulating no major gene effect, random environmental transmission, recessive inheritance, and sporadic occurrence were rejected under varied assumptions regarding the associations among sex, age, and major gene susceptibility. Transmission of the disorder was not fully explained by a single Mendelian model for all families. Stratification of families as early- and late-onset by using the median of family mean onset ages showed that, regardless of the model studied, two groups of families fit bettermore » than a single group. AD in early-onset families is transmitted as an autosomal dominant trait with full penetrance in both sexes and has a gene frequency of 1.5%. Dominant inheritance also gave the best fit of the data in late-onset families, but this hypothesis was rejected, suggesting the presence of heterogeneity within this subset. Our study also revealed that genetically nonsusceptible males and females develop AD, indicating the presence of phenocopies within early-onset and late-onset groups. Moreover, our results suggest that the higher risk to females is not solely due to their increased longevity. 50 refs., 5 tabs.« less

An inherited variable poly-T repeat genotype in TOMM40 in Alzheimer disease.

PubMed

Roses, Allen D

2010-05-01

I coauthored a recently published research article describing a variable length, poly-T polymorphism in the TOMM40 gene, adjacent to apolipoprotein E (APOE) on chromosome 19, that accounts for the age at onset distribution for a complex disease, late-onset Alzheimer disease. These new data explain the mean age at disease onset for patients with the APOE4/4 genotype and differentiate 2 forms of TOMM40 poly-T polymorphisms linked to APOE, with each form associated with a different age at disease onset distribution. When linked to APOE3 (encoding the epsilon3 isoform of APOE), the longer TOMM40 poly-T repeats (19-39 nucleotides) at the rs10524523 (hereafter, 523) locus are associated with earlier age at onset and the shorter TOMM40 523 alleles (11-16 nucleotides) are associated with later age at onset. The data suggest that the poly-T alleles are codominant, with the age at onset phenotype determined by the 2 inherited 523 alleles, but with variable expressivity. Additional data will further refine the relationship between the length of the poly-T alleles and age at disease onset and determine if the relationship is linear.

Brain Differences in Infants at Differential Genetic Risk for Late-Onset Alzheimer Disease A Cross-sectional Imaging Study

PubMed Central

Dean, Douglas C.; Jerskey, Beth A.; Chen, Kewei; Protas, Hillary; Thiyyagura, Pradeep; Roontiva, Auttawat; O’Muircheartaigh, Jonathan; Dirks, Holly; Waskiewicz, Nicole; Lehman, Katie; Siniard, Ashley L.; Turk, Mari N.; Hua, Xue; Madsen, Sarah K.; Thompson, Paul M.; Fleisher, Adam S.; Huentelman, Matthew J.; Deoni, Sean C. L.; Reiman, Eric M.

2014-01-01

IMPORTANCE Converging evidence suggests brain structure alterations may precede overt cognitive impairment in Alzheimer disease by several decades. Early detection of these alterations holds inherent value for the development and evaluation of preventive treatment therapies. OBJECTIVE To compare magnetic resonance imaging measurements of white matter myelin water fraction (MWF) and gray matter volume (GMV) in healthy infant carriers and noncarriers of the apolipoprotein E (APOE) ε4 allele, the major susceptibility gene for late-onset AD. DESIGN, SETTING, AND PARTICIPANTS Quiet magnetic resonance imaging was performed at an academic research imaging center on 162 healthy, typically developing 2- to 25-month-old infants with no family history of Alzheimer disease or other neurological or psychiatric disorders. Cross-sectional measurements were compared in the APOE ε4 carrier and noncarrier groups. White matter MWF was compared in one hundred sixty-two 2- to 25-month-old sleeping infants (60 ε4 carriers and 102 noncarriers). Gray matter volume was compared in a subset of fifty-nine 6- to 25-month-old infants (23 ε4 carriers and 36 noncarriers), who remained asleep during the scanning session. The carrier and noncarrier groups were matched for age, gestational duration, birth weight, sex ratio, maternal age, education, and socioeconomic status. MAIN OUTCOMES AND MEASURES Automated algorithms compared regional white matter MWF and GMV in the carrier and noncarrier groups and characterized their associations with age. RESULTS Infant ε4 carriers had lower MWF and GMV measurements than noncarriers in precuneus, posterior/middle cingulate, lateral temporal, and medial occipitotemporal regions, areas preferentially affected by AD, and greater MWF and GMV measurements in extensive frontal regions and measurements were also significant in the subset of 2- to 6-month-old infants (MWF differences, P < .05, after correction for multiple comparisons; GMV differences, P < .001

Alpha-1-antichymotrypsin (ACT or SERPINA3) polymorphism may affect age-at-onset and disease duration of Alzheimer's disease.

PubMed

Kamboh, M Ilyas; Minster, Ryan L; Kenney, Margaret; Ozturk, Ayla; Desai, Purnima P; Kammerer, Candace M; DeKosky, Steven T

2006-10-01

In addition to genetic effects on disease risk, age-at-onset (AAO) of Alzheimer's disease (AD) is also genetically controlled. Using AAO as a covariate, a linkage signal for AD has been detected on chromosome 14q32 near the alpha1-antichymotrypsin (ACT) gene. Previously, a signal peptide polymorphism (codon -17A>T) in the ACT gene has been suggested to affect AD risk, but with inconsistent findings. Given that a linkage signal for AAO has been detected near ACT, we hypothesized that ACT genetic variation affects AAO rather than disease risk and this may explain the previous inconsistent findings between ACT genetic variation and AD risk. We examined the impact of the ACT signal peptide polymorphism on mean AAO in 909 AD cases. The ACT polymorphism was significantly associated with AAO and this effect was independent of the APOE polymorphism. Mean AAO among ACT/AA homozygotes was significantly lower than that in the combined AT+TT genotype group (p = 0.019) and this difference was confined to male AD patients (p = 0.002). Among male AD patients, the ACT/AA genotype was also associated with shorter disease duration before death as compared to the ACT/AT+TT genotypes (p = 0.012). These data suggest that the ACT gene may affect AAO and disease duration of AD.

Advances in Alzheimer's imaging are changing the experience of Alzheimer's disease.

PubMed

Stites, Shana D; Milne, Richard; Karlawish, Jason

2018-01-01

Neuroimaging is advancing a new definition of Alzheimer's disease (AD). Using imaging biomarkers, clinicians may begin to diagnose the disease by identifying pathology and neurodegeneration in either cognitively impaired or unimpaired adults. This "biomarker-based" diagnosis may allow clinicians novel opportunities to use interventions that either delay the onset or slow the progression of cognitive decline, but it will also bring novel challenges. How will changing the definition of AD from a clinical to a biomarker construct change the experience of living with the disease? Knowledge of AD biomarker status can affect how individuals feel about themselves (internalized stigma) and how others judge them (public stigma). Following a review of AD stigma, we appraise how advances in diagnosis may enable or interrupt its transfer from clinical to preclinical stages and then explore conceptual and pragmatic challenges to addressing stigma in routine care.

Construction of a yeast artificial chromosome contig encompassing the chromosome 14 Alzheimer`s disease locus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharma, V.; Bonnycastle, L.; Poorkai, P.

1994-09-01

We have constructed a yeast artificial chromosome (YAC) contig of chromosome 14q24.3 which encompasses the chromosome 14 Alzheimer`s disease locus (AD3). Determined by linkage analysis of early-onset Alzheimer`s disease kindreds, this interval is bounded by the genetic markers D14S61-D14S63 and spans approximately 15 centimorgans. The contig consists of 29 markers and 74 YACs of which 57 are defined by one or more sequence tagged sites (STSs). The STS markers comprise 5 genes, 16 short tandem repeat polymorphisms and 8 cDNA clones. An additional number of genes, expressed sequence tags and cDNA fragments have been identified and localized to the contigmore » by hybridization and sequence analysis of anonymous clones isolated by cDNA direct selection techniques. A minimal contig of about 15 YACs averaging 0.5-1.5 megabase in length will span this interval and is, at first approximation, in rough agreement with the genetic map. For two regions of the contig, our coverage has relied on L1/THE fingerprint and Alu-PCR hybridization data of YACs provided by CEPH/Genethon. We are currently developing sequence tagged sites from these to confirm the overlaps revealed by the fingerprint data. Among the genes which map to the contig are transforming growth factor beta 3, c-fos, and heat shock protein 2A (HSPA2). C-fos is not a candidate gene for AD3 based on the sequence analysis of affected and unaffected individuals. HSPA2 maps to the proximal edge of the contig and Calmodulin 1, a candidate gene from 4q24.3, maps outside of the region. The YAC contig is a framework physical map from which cosmid or P1 clone contigs can be constructed. As more genes and cDNAs are mapped, a highly resolved transcription map will emerge, a necessary step towards positionally cloning the AD3 gene.« less

New-onset epilepsy in the elderly.

PubMed

Vu, Lily Chi; Piccenna, Loretta; Kwan, Patrick; O'Brien, Terence J

2018-06-01

People who are 60 years old and older have the highest incidence of developing new-onset epilepsy. The increase of the ageing population has resulted in a greater number of patients with new-onset epilepsy or at risk of developing the condition. Previously published review articles regarding epilepsy in older patients have had a broad focus, including people who were diagnosed with epilepsy in childhood or in middle age. This review focuses on the causes, treatment, prognosis and psychosocial impact of new-onset epilepsy in people aged 60 years and over. Following a search of the medical electronic databases and relevant references, we identified 22 studies overall that met the inclusion criteria. Only four randomised clinical trials (RCTs) were identified comparing different antiepileptic drug treatments in this population, demonstrating that newer generation antiepileptic drugs, e.g. lamotrigine and levetiracetam, were generally better tolerated. One uncontrolled study provided promising evidence of good outcomes and safety for surgical resection as a treatment for people with uncontrolled seizures. Five studies reported that people 60 years and over with new-onset epilepsy have significant cognitive impairments, e.g. memory, and psychological issues including depression, anxiety and fatigue. We found that there is very limited evidence to guide treatment in people with Alzheimer's disease and epilepsy. The specific features of new-onset epilepsy in this target population significantly influences the choice of treatment. Cognitive and psychiatric screening before treatment may be useful for management. Two studies with proposed guidelines were identified, but no formal clinical practice guidelines exist for this special population to assist with appropriate management. There is a need for more RCTs that investigate effective treatments with limited side effects. More research studies on the psychosocial effects of new onset epilepsy, and long-term outcomes, for

Bacteriophage--a common divergent therapeutic approach for Alzheimer's disease and type II diabetes mellitus.

PubMed

Sohrab, Sayed S; Karim, Sajjad; Kamal, Mohammad A; Abuzenadah, Adel M; Chaudhary, Adeel G; Al-Qahtani, Mohammed H; Mirza, Zeenat

2014-04-01

Alzheimer's disease, the most important neurodegenerative disorder, is an irreversible, age-dependent disease of the brain characterized by problems in progressive impairments in memory, language, reasoning, behavior and visuospatial skills. It is characterized by the deposition of amyloid beta peptide, forming compact fibrillar plaques and neurofibrillary tau tangles. Another major and much more prevalent cause of morbidity and mortality in world is diabetes especially type 2 diabetes mellitus. It is caused by a combination of resistance to insulin action and an inadequate compensatory insulin secretory response. Chronic wounds caused by antibiotic resistant bacterial infections that fail to heal are a common complication of diabetes mellitus and the most frequent reason for nontraumatic lower limb amputation. Holistically, these two diseases are linked at molecular level but the exact mechanism is a topic of debate. Bacteriophages are viruses infecting bacteria and lack ability to infect mammalian cells. They are neither causative agent for Alzheimer's disease or type 2 diabetes mellitus nor involved in their pathogenicity but promises for a novel divergent therapeutic approach. The great versatility of the phage system has led to the development of improved phage delivery vectors, as well as immunomodulation of anti-amyloid beta peptide response. Phages could also constitute valuable prophylaxis against bacterial infections, especially in immunocompromised patients like in the case of diabetes. Patients having diabetes have a high risk of developing foot ulcers which are difficult to be treated by antibiotics alone due to ever increasing antibiotic resistance strains. Combination therapy based on multiple phage and broad spectrum antibiotics holds great promise. The potential therapeutic phage therapy arises from its lack of natural tropism for mammalian cells, resulting in no adverse effects.

Mutation screening of patients with Alzheimer disease identifies APP locus duplication in a Swedish patient

PubMed Central

2011-01-01

Background Missense mutations in three different genes encoding amyloid-β precursor protein, presenilin 1 and presenilin 2 are recognized to cause familial early-onset Alzheimer disease. Also duplications of the amyloid precursor protein gene have been shown to cause the disease. At the Dept. of Geriatric Medicine, Karolinska University Hospital, Sweden, patients are referred for mutation screening for the identification of nucleotide variations and for determining copy-number of the APP locus. Methods We combined the method of microsatellite marker genotyping with a quantitative real-time PCR analysis to detect duplications in patients with Alzheimer disease. Results In 22 DNA samples from individuals diagnosed with clinical Alzheimer disease, we identified one patient carrying a duplication on chromosome 21 which included the APP locus. Further mapping of the chromosomal region by array-comparative genome hybridization showed that the duplication spanned a maximal region of 1.09 Mb. Conclusions This is the first report of an APP duplication in a Swedish Alzheimer patient and describes the use of quantitative real-time PCR as a tool for determining copy-number of the APP locus. PMID:22044463

Mutation screening of patients with Alzheimer disease identifies APP locus duplication in a Swedish patient.

PubMed

Thonberg, Håkan; Fallström, Marie; Björkström, Jenny; Schoumans, Jacqueline; Nennesmo, Inger; Graff, Caroline

2011-11-01

Missense mutations in three different genes encoding amyloid-β precursor protein, presenilin 1 and presenilin 2 are recognized to cause familial early-onset Alzheimer disease. Also duplications of the amyloid precursor protein gene have been shown to cause the disease. At the Dept. of Geriatric Medicine, Karolinska University Hospital, Sweden, patients are referred for mutation screening for the identification of nucleotide variations and for determining copy-number of the APP locus. We combined the method of microsatellite marker genotyping with a quantitative real-time PCR analysis to detect duplications in patients with Alzheimer disease. In 22 DNA samples from individuals diagnosed with clinical Alzheimer disease, we identified one patient carrying a duplication on chromosome 21 which included the APP locus. Further mapping of the chromosomal region by array-comparative genome hybridization showed that the duplication spanned a maximal region of 1.09 Mb. This is the first report of an APP duplication in a Swedish Alzheimer patient and describes the use of quantitative real-time PCR as a tool for determining copy-number of the APP locus.

A second locus for very-late-onset Alzheimer disease: a genome scan reveals linkage to 20p and epistasis between 20p and the amyloid precursor protein region.

PubMed

Olson, Jane M; Goddard, Katrina A B; Dudek, Doreen M

2002-07-01

We used a covariate-based linkage method to reanalyze genome scan data from affected sibships collected by the Alzheimer Disease (AD) Genetics Initiative of the National Institute of Mental Health. As reported in an earlier article, the amyloid-beta precursor protein (APP) region is strongly linked to affected sib pairs of the oldest current age (i.e., age either at last exam or at death) who lack E4 alleles at the apolipoprotein E (ApoE) locus. We now report that a region on 20p shows the same pattern. A model that includes current age and the number of E2 alleles as covariates gives a LOD score of 4.1. The signal on 20p is near the location of the gene coding for cystatin-C, previously shown to be associated with late-onset AD and to codeposit with APP in the brains of patients with AD. Two-locus analysis provides evidence of strong epistasis between 20p and the APP region, limited to the oldest age group and to those lacking ApoE4 alleles. We speculate that high-risk polymorphisms in both regions produce a biological interaction between these two proteins that increases susceptibility to a very-late-onset form of AD.

Obesity and type 2 diabetes mellitus in a birth cohort of First Nation children born to mothers with pediatric-onset type 2 diabetes.

PubMed

Mendelson, Michael; Cloutier, Justin; Spence, Louise; Sellers, Elizabeth; Taback, Shayne; Dean, Heather

2011-05-01

Children who are born to mothers with pediatric-onset type 2 diabetes mellitus are exposed to a hyperglycemic intra-uterine environment throughout pregnancy. The growth patterns and risk of type 2 diabetes in these offspring may be influenced by unique gene-environment interactions during intra-uterine and postnatal life. We established a cohort of offspring of First Nation mothers with onset of type 2 diabetes before age 18 years in Manitoba, Canada. We measured height or length and weight at study entry and annually thereafter with fasting blood glucose in offspring aged ≥ 7 years. We collected birth and breastfeeding history and determined the population-specific hepatic nuclear factor-1α (HNF-1α) G319S genotype of offspring at age 7 years. From July 2003 to April 2008, we enrolled 76 offspring of 37 mothers. Sixty-four percent (23/36) of the offspring aged 2-19 years were obese at initial assessment. The rates of obesity remained constant throughout the 5 years. As of April 2008, 7/28 (25%) of the offspring aged 7-19 years have diabetes including 6/14 (43%) aged 10-19 years. Most offspring with diabetes (5/7, 71%) were obese at diagnosis. All of the 7 offspring with diabetes have 1 or 2 copies of the G319S polymorphism. The prevalence of type 2 diabetes in this cohort of offspring of First Nation women with pediatric-onset type 2 diabetes is the highest ever reported. Obesity is an important postnatal risk factor for type 2 diabetes in this population and may result from a unique gene-environment interaction. © 2011 John Wiley & Sons A/S.

Inhibition of GSK-3 Ameliorates Aβ Pathology in an Adult-Onset Drosophila Model of Alzheimer's Disease

PubMed Central

Killick, Richard; Augustin, Hrvoje; Gandy, Carina; Allen, Marcus J.; Hardy, John; Lovestone, Simon; Partridge, Linda

2010-01-01

Aβ peptide accumulation is thought to be the primary event in the pathogenesis of Alzheimer's disease (AD), with downstream neurotoxic effects including the hyperphosphorylation of tau protein. Glycogen synthase kinase-3 (GSK-3) is increasingly implicated as playing a pivotal role in this amyloid cascade. We have developed an adult-onset Drosophila model of AD, using an inducible gene expression system to express Arctic mutant Aβ42 specifically in adult neurons, to avoid developmental effects. Aβ42 accumulated with age in these flies and they displayed increased mortality together with progressive neuronal dysfunction, but in the apparent absence of neuronal loss. This fly model can thus be used to examine the role of events during adulthood and early AD aetiology. Expression of Aβ42 in adult neurons increased GSK-3 activity, and inhibition of GSK-3 (either genetically or pharmacologically by lithium treatment) rescued Aβ42 toxicity. Aβ42 pathogenesis was also reduced by removal of endogenous fly tau; but, within the limits of detection of available methods, tau phosphorylation did not appear to be altered in flies expressing Aβ42. The GSK-3–mediated effects on Aβ42 toxicity appear to be at least in part mediated by tau-independent mechanisms, because the protective effect of lithium alone was greater than that of the removal of tau alone. Finally, Aβ42 levels were reduced upon GSK-3 inhibition, pointing to a direct role of GSK-3 in the regulation of Aβ42 peptide level, in the absence of APP processing. Our study points to the need both to identify the mechanisms by which GSK-3 modulates Aβ42 levels in the fly and to determine if similar mechanisms are present in mammals, and it supports the potential therapeutic use of GSK-3 inhibitors in AD. PMID:20824130

Association studies of 23 positional/functional candidate genes on chromosome 10 in late-onset Alzheimer's disease.

PubMed

Morgan, A R; Turic, D; Jehu, L; Hamilton, G; Hollingworth, P; Moskvina, V; Jones, L; Lovestone, S; Brayne, C; Rubinsztein, D C; Lawlor, B; Gill, M; O'Donovan, M C; Owen, M J; Williams, J

2007-09-05

Late-onset Alzheimer's disease (LOAD) is a common neurodegenerative disorder, with a complex etiology. APOE is the only confirmed susceptibility gene for LOAD. Others remain yet to be found. Evidence from linkage studies suggests that a gene (or genes) conferring susceptibility for LOAD resides on chromosome 10. We studied 23 positional/functional candidate genes from our linkage region on chromosome 10 (APBB1IP, ALOX5, AD037, SLC18A3, DKK1, ZWINT, ANK3, UBE2D1, CDC2, SIRT1, JDP1, NET7, SUPV3L1, NEN3, SAR1, SGPL1, SEC24C, CAMK2G, PP3CB, SNCG, CH25H, PLCE1, ANXV111) in the MRC genetic resource for LOAD. These candidates were screened for sequence polymorphisms in a sample of 14 LOAD subjects and detected polymorphisms tested for association with LOAD in a three-stage design involving two stages of genotyping pooled DNA samples followed by a third stage in which markers showing evidence for association in the first stages were subjected to individual genotyping. One hundred and twenty polymorphisms were identified and tested in stage 1 (4 case + 4 control pools totaling 366 case and 366 control individuals). Single nucleotide polymorphisms (SNPs) showing evidence of association with LOAD were then studied in stage 2 (8 case + 4 control pools totaling 1,001 case and 1,001 control individuals). Five SNPs, in four genes, showed evidence for association (P < 0.1) at stage 2 and were individually genotyped in the complete dataset, comprising 1,160 LOAD cases and 1,389 normal controls. Two SNPs in SGPL1 demonstrated marginal evidence of association, with uncorrected P values of 0.042 and 0.056, suggesting that variation in SGPL1 may confer susceptibility to LOAD. Copyright 2007 Wiley-Liss, Inc.

Familial early-onset dementia with tau intron 10 + 16 mutation with clinical features similar to those of Alzheimer disease.

PubMed

Doran, Mark; du Plessis, Daniel G; Ghadiali, Eric J; Mann, David M A; Pickering-Brown, Stuart; Larner, Andrew J

2007-10-01

Frontotemporal dementia with parkinsonism linked to chromosome 17 (FTDP-17) owing to the tau intron 10 + 16 mutation usually occurs with a prototypical frontotemporal dementia phenotype with prominent disinhibition and affective disturbances. To report a new FTDP-17 pedigree with the tau intron 10 + 16 mutation demonstrating a clinical phenotype suggestive of Alzheimer disease. Case reports. Regional neuroscience centers in northwest England. Patients We examined 4 members of a kindred in which 8 individuals were affected in 3 generations. All 4 patients reported memory difficulty. Marked anomia was also present, but behavioral disturbances were conspicuously absent in the early stages of disease. All patients had an initial clinical diagnosis of Alzheimer disease. No mutations were found in the presenilin or amyloid precursor protein genes. Pathologic examination of the proband showed features typical of FTDP-17, and tau gene analysis showed the intron 10 + 16 mutation. This pedigree illustrates the phenotypic variability of tau intron 10 + 16 mutations. In pedigrees with a clinical diagnosis of Alzheimer disease but without presenilin or amyloid precursor protein gene mutations, tau gene mutations may be found.

The executive prominent/memory prominent spectrum in Alzheimer's disease is highly heritable.

PubMed

Mez, Jesse; Mukherjee, Shubhabrata; Thornton, Timothy; Fardo, David W; Trittschuh, Emily; Sutti, Sheila; Sherva, Richard; Kauwe, John S; Naj, Adam C; Beecham, Gary W; Gross, Alden; Saykin, Andrew J; Green, Robert C; Crane, Paul K

2016-05-01

Late-onset Alzheimer's disease (LOAD) can present heterogeneously, with several subtypes recognized, including dysexecutive AD. One way to identify people with dysexecutive AD is to consider the difference between memory and executive functioning, which we refer to as the executive prominent/memory prominent spectrum. We aimed to determine if this spectrum was heritable. We used neuropsychological and genetic data from people with mild LOAD (Clinical Dementia Rating 0.5 or 1.0) from the National Alzheimer's Coordinating Center and the Alzheimer's Disease Neuroimaging Initiative. We cocalibrated the neuropsychological data to obtain executive functioning and memory scores and used their difference as a continuous phenotype to calculate its heritability overall and by chromosome. Narrow-sense heritability of the difference between memory and executive functioning scores was 0.68 (standard error 0.12). Single nucleotide polymorphisms on chromosomes 1, 2, 4, 11, 12, and 18 explained the largest fraction of phenotypic variance, with signals from each chromosome accounting for 5%-7%. The chromosomal pattern of heritability differed substantially from that of LOAD itself. Copyright © 2016 Elsevier Inc. All rights reserved.

No association of SORL1 SNPs with Alzheimer's disease.

PubMed

Minster, Ryan L; DeKosky, Steven T; Kamboh, M Ilyas

2008-08-01

SORL1 is an element of the amyloid precursor protein processing pathway and is therefore a good candidate for affecting Alzheimer's disease (AD) risk. Indeed, there have been reports of associations between variation in SORL1 and AD risk. We examined six statistically significant single-nucleotide polymorphisms from the initial observation in a large Caucasian American case-controls cohort (1000 late-onset AD [LOAD] cases and 1000 older controls). Analysis of allele, genotype and haplotype frequencies revealed no association with LOAD risk in our cohort.

Senile dementia of the Alzheimer type treated with aniracetam: a new nootropic agent.

PubMed

Sourander, L B; Portin, R; Mölsä, P; Lahdes, A; Rinne, U K

1987-01-01

Forty-four patients with senile dementia of the Alzheimer type were randomly allocated into double-blind treatment with either aniracetam (RO 13-5057) 1 g or placebo daily for 3 months. Neurological examinations were made before and after treatment and psychometric tests were performed before and after 1 month's and after 3 month's treatment. Treatment was interrupted due to occurrence of confusion in four cases in the aniracetam group and in one case in the placebo group. During treatment, an improvement was seen in several cognitive tests, especially those associated with memory, but this improvement occurred in the placebo as well as in the aniracetam-treated group. In clinical evaluation no difference was seen in efficacy between the two treatment groups.

Tracking discourse complexity preceding Alzheimer's disease diagnosis: a case study comparing the press conferences of Presidents Ronald Reagan and George Herbert Walker Bush.

PubMed

Berisha, Visar; Wang, Shuai; LaCross, Amy; Liss, Julie

2015-01-01

Changes in some lexical features of language have been associated with the onset and progression of Alzheimer's disease. Here we describe a method to extract key features from discourse transcripts, which we evaluated on non-scripted news conferences from President Ronald Reagan, who was diagnosed with Alzheimer's disease in 1994, and President George Herbert Walker Bush, who has no known diagnosis of Alzheimer's disease. Key word counts previously associated with cognitive decline in Alzheimer's disease were extracted and regression analyses were conducted. President Reagan showed a significant reduction in the number of unique words over time and a significant increase in conversational fillers and non-specific nouns over time. There was no significant trend in these features for President Bush.

Sigma receptor type 1 gene variation in a group of Polish patients with Alzheimer's disease and mild cognitive impairment.

PubMed

Maruszak, Aleksandra; Safranow, Krzysztof; Gacia, Magdalena; Gabryelewicz, Tomasz; Słowik, Agnieszka; Styczyńska, Maria; Pepłońska, Beata; Golan, Maciej P; Zekanowski, Cezary; Barcikowska, Maria

2007-01-01

The sigma-1 receptor (SIGMAR1) is a subtype of a nonopioid sigma receptor family and is implicated in numerous functions connected with Alzheimer's disease (AD). Two common genetic variants were identified in SIGMAR1: GC-241 -240TT and Q2P (A61C). It was suggested that the TT-C haplotype is a protective factor for AD. We decided to investigate a putative link between the variants of SIGMAR1 and AD in a group of Polish patients with late-onset AD, in patients with mild cognitive impairment, and in a control group. We observed no significant differences for the SIGMAR1 allele, genotype, haplotype, and diplotype distributions between the studied groups. Multivariate logistic regression analysis showed no interaction between the APOE4 and SIGMAR1 polymorphisms. Further studies using data from different populations are required to elucidate the effect of SIGMAR1 polymorphisms on AD.

Genetic association between the interleukin-2 receptor-alpha gene and mode of onset of type 1 diabetes in the Japanese population.

PubMed

Kawasaki, Eiji; Awata, Takuya; Ikegami, Hiroshi; Kobayashi, Tetsuro; Maruyama, Taro; Nakanishi, Koji; Shimada, Akira; Uga, Miho; Kurihara, Susumu; Kawabata, Yumiko; Tanaka, Shoichiro; Kanazawa, Yasuhiko; Eguchi, Katsumi

2009-03-01

The IL-2 receptor-alpha (IL2RA), also known as CD25, is expressed on the regulatory T cells, which play an important role in the control of immune responses and the maintenance of immune homeostasis. Our objective was to determine whether variants in the IL2RA gene are associated with type 1 diabetes in the Japanese population. We genotyped the four single-nucleotide polymorphisms (rs706778, rs3118470, ss52580101, and rs11594656) of the IL2RA in 885 patients with type 1 diabetes and 606 control subjects of Japanese origin. The allele and genotype frequencies were examined in the patient groups stratified by their mode of onset in a case-control study. We found evidence of association with acute-onset, but not slow-onset and fulminant, type 1 diabetes for two of the four single-nucleotide polymorphisms genotyped (rs706778 and rs3118470). The rs706778 A allele and the rs3118470 G allele were associated with an increased disease risk [odds ratio (OR) for rs706778 AA genotype 1.54, P = 4.2 x 10(-4) and OR for rs3118470 GG genotype 1.50, P = 0.0019, respectively]. Furthermore, the A-G haplotype was associated with increased type 1 diabetes risk in the acute-onset form (OR 1.30, P = 0.002). The present data confirm the type 1 diabetes association with IL2RA and provide evidence that the different contributions of the IL2RA in the susceptibility to acute-onset and other forms of type 1 diabetes in the Japanese population.

Collaboration Is Key for Successful Treatment of Youth-Onset Type 2 Diabetes.

PubMed

Folsom, Lisal J; Hannon, Tamara S

2017-04-01

Type 2 diabetes (T2D) is increasing in U.S. adolescents, particularly those of ethnic and racial minority groups. Risk factors for youth-onset T2D include obesity, family history of T2D, poor diet, lack of exercise, and poverty. The onset of diabetes-related complications is accelerated in adolescents with T2D compared to adults, and knowledge regarding the optimal way to prevent and slow complications is lacking. Existing treatment options are limited, and research into novel pharmacologic treatments is hindered by lack of sufficient patient population for clinical trials. Health care providers and investigators should collaborate both with each other, and with patients and their communities to build networks that will allow comprehensive evaluation of this disease in order to offer optimal, comprehensive care for these adolescents. Copyright © 2017 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Cerebral amyloid angiopathy in Down syndrome and sporadic and autosomal-dominant Alzheimer's disease.

PubMed

Carmona-Iragui, María; Balasa, Mircea; Benejam, Bessy; Alcolea, Daniel; Fernández, Susana; Videla, Laura; Sala, Isabel; Sánchez-Saudinós, María Belén; Morenas-Rodriguez, Estrella; Ribosa-Nogué, Roser; Illán-Gala, Ignacio; Gonzalez-Ortiz, Sofía; Clarimón, Jordi; Schmitt, Frederick; Powell, David K; Bosch, Beatriz; Lladó, Albert; Rafii, Michael S; Head, Elizabeth; Molinuevo, José Luis; Blesa, Rafael; Videla, Sebastián; Lleó, Alberto; Sánchez-Valle, Raquel; Fortea, Juan

2017-11-01

We aimed to investigate if cerebral amyloid angiopathy (CAA) is more frequent in genetically determined than in sporadic early-onset forms of Alzheimer's disease (AD) (early-onset AD [EOAD]). Neuroimaging features of CAA, apolipoprotein (APOE), and cerebrospinal fluid amyloid β (Aβ) 40 levels were studied in subjects with Down syndrome (DS, n = 117), autosomal-dominant AD (ADAD, n = 29), sporadic EOAD (n = 42), and healthy controls (n = 68). CAA was present in 31%, 38%, and 12% of cognitively impaired DS, symptomatic ADAD, and sporadic EOAD subjects and in 13% and 4% of cognitively unimpaired DS individuals and healthy controls, respectively. APOE ε4 genotype was borderline significantly associated with CAA in sporadic EOAD (P = .06) but not with DS or ADAD. There were no differences in Aβ040 levels between groups or between subjects with and without CAA. CAA is more frequently found in genetically determined AD than in sporadic EOAD. Cerebrospinal fluid Aβ40 levels are not a useful biomarker for CAA in AD. Copyright © 2017 the Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

Errorless-based techniques can improve route finding in early Alzheimer's disease: a case study.

PubMed

Provencher, Véronique; Bier, Nathalie; Audet, Thérèse; Gagnon, Lise

2008-01-01

Topographical disorientation is a common and early manifestation of dementia of Alzheimer type, which threatens independence in activities of daily living. Errorless-based techniques appear to be effective in helping patients with amnesia to learn routes, but little is known about their effectiveness in early dementia of Alzheimer type. A 77-year-old woman with dementia of Alzheimer type had difficulty in finding her way around her seniors residence, which reduced her social activities. This study used an ABA design (A is the baseline and B is the intervention) with multiple baselines across routes for going to the rosary (target), laundry, and game rooms (controls). The errorless-based technique intervention was applied to 2 of the 3 routes. Analyses showed significant improvement only for the routes learned with errorless-based techniques. Following the study, the participant increased her topographical knowledge of her surroundings. Route learning interventions based on errorless-based techniques appear to be a promising approach for improving the independence in early dementia of Alzheimer type.

An APOE-independent cis-eSNP on chromosome 19q13.32 influences tau levels and late-onset Alzheimer's disease risk.

PubMed

Rao, Shuquan; Ghani, Mahdi; Guo, Zhiyun; Deming, Yuetiva; Wang, Kesheng; Sims, Rebecca; Mao, Canquan; Yao, Yao; Cruchaga, Carlos; Stephan, Dietrich A; Rogaeva, Ekaterina

2018-06-01

Although multiple susceptibility loci for late-onset Alzheimer's disease (LOAD) have been identified, a large portion of the genetic risk for this disease remains unexplained. LOAD risk may be associated with single-nucleotide polymorphisms responsible for changes in gene expression (eSNPs). To detect eSNPs associated with LOAD, we integrated data from LOAD genome-wide association studies and expression quantitative trait loci using Sherlock (a Bayesian statistical method). We identified a cis-regulatory eSNP (rs2927438) located on chromosome 19q13.32, for which subsequent analyses confirmed the association with both LOAD risk and the expression level of several nearby genes. Importantly, rs2927438 may represent an APOE-independent LOAD eSNP according to the weak linkage disequilibrium of rs2927438 with the 2 polymorphisms (rs7412 and rs429358) defining the APOE-ε2, -ε3, and -ε4 alleles. Furthermore, rs2927438 does not influence chromatin interaction events at the APOE locus or cis-regulation of APOE expression. Further exploratory analysis revealed that rs2927438 is significantly associated with tau levels in the cerebrospinal fluid. Our findings suggest that rs2927438 may confer APOE-independent risk for LOAD. Copyright © 2017 Elsevier Inc. All rights reserved.

Mutant SOD1 in cell types other than motor neurons and oligodendrocytes accelerates onset of disease in ALS mice

PubMed Central

Yamanaka, Koji; Boillee, Severine; Roberts, Elizabeth A.; Garcia, Michael L.; McAlonis-Downes, Melissa; Mikse, Oliver R.; Cleveland, Don W.; Goldstein, Lawrence S. B.

2008-01-01

Dominant mutations in ubiquitously expressed superoxide dismutase (SOD1) cause familial ALS by provoking premature death of adult motor neurons. To test whether mutant damage to cell types beyond motor neurons is required for the onset of motor neuron disease, we generated chimeric mice in which all motor neurons and oligodendrocytes expressed mutant SOD1 at a level sufficient to cause fatal, early-onset motor neuron disease when expressed ubiquitously, but did so in a cellular environment containing variable numbers of non-mutant, non-motor neurons. Despite high-level mutant expression within 100% of motor neurons and oligodendrocytes, in most of these chimeras, the presence of WT non-motor neurons substantially delayed onset of motor neuron degeneration, increasing disease-free life by 50%. Disease onset is therefore non-cell autonomous, and mutant SOD1 damage within cell types other than motor neurons and oligodendrocytes is a central contributor to initiation of motor neuron degeneration. PMID:18492803

N-terminal pro-B-type Natriuretic Peptide in three different mechanisms of dysnatremia onset after a child's craniopharyngioma surgery.

PubMed

Spatenkova, Vera; Hradil, Jan; Suchomel, Petr

2017-10-01

Craniopharyngioma, due to its sellar location, can be perioperatively complicated by different types of dysnatremia. We present a rare postoperative onset of a combination of three different mechanisms of dysnatremia with N-terminal pro-B-type Natriuretic Peptide (NT-proBNP) and renal function parameters in a boy with a good outcome after craniopharyngioma surgery: 1/ Central diabetes insipidus (CDI) onset immediately after the operation, hypernatremia with peak serum sodium (SNa) 158 mmol/l) caused by free water polyuria (electrolyte-free water clearance, EWC 0.104 ml/s), NT-proBNP 350 pg/ml; 2/ cerebral salt wasting (CSW) onset on day 7, hyponatremia (SNa 128 mmol/l) with hypoosmolality (measured serum osmolality, SOsm 265 mmol/kg) caused by natriuresis (sodium - daily output 605 mmol/day, fractional excretion 0.035), NT-proBNP 191 pg/ml; 3/ Polydypsia onset on day 11 caused hyponatremia (SNa 132 mmol/l), EWC 0.015, NT-proBNP 68 pg/ml.

Alzheimer disease and cognitive impairment associated with diabetes mellitus type 2: associations and a hypothesis.

PubMed

Domínguez, R O; Pagano, M A; Marschoff, E R; González, S E; Repetto, M G; Serra, J A

2014-01-01

Epidemiological studies have demonstrated that patients with diabetes mellitus have an increased risk of developing Alzheimer disease, but the relationship between the 2 entities is not clear. Both diseases exhibit similar metabolic abnormalities: disordered glucose metabolism, abnormal insulin receptor signalling and insulin resistance, oxidative stress, and structural abnormalities in proteins and β-amyloid deposits. Different hypotheses have emerged from experimental work in the last two decades. One of the most comprehensive relates the microvascular damage in diabetic polyneuritis with the central nervous system changes occurring in Alzheimer disease. Another hypothesis considers that cognitive impairment in both diabetes and Alzheimer disease is linked to a state of systemic oxidative stress. Recently, attenuation of cognitive impairment and normalisation of values in biochemical markers for oxidative stress were found in patients with Alzheimer disease and concomitant diabetes. Antidiabetic drugs may have a beneficial effect on glycolysis and its end products, and on other metabolic alterations. Diabetic patients are at increased risk for developing Alzheimer disease, but paradoxically, their biochemical alterations and cognitive impairment are less pronounced than in groups of dementia patients without diabetes. A deeper understanding of interactions between the pathogenic processes of both entities may lead to new therapeutic strategies that would slow or halt the progression of impairment. Copyright © 2013 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

Variants in CYP17 and CYP19 cytochrome P450 genes are associated with onset of Alzheimer's disease in women with down syndrome.

PubMed

Chace, Constance; Pang, Deborah; Weng, Catherine; Temkin, Alexis; Lax, Simon; Silverman, Wayne; Zigman, Warren; Ferin, Michel; Lee, Joseph H; Tycko, Benjamin; Schupf, Nicole

2012-01-01

CYP17 and CYP19 are involved in the peripheral synthesis of estrogens, and polymorphisms in CYP17 and CYP19 have been associated with increased risk of estrogen-related disorders. Women with Down syndrome (DS) have early onset and high risk for Alzheimer's disease (AD). We conducted a prospective community-based cohort study to examine the relationship between SNPs in CYP17 and CYP19 and cumulative incidence of AD, hormone levels and sex hormone binding globulin in women with DS. Two hundred and thirty-five women with DS, 31 to 67 years of age and nondemented at initial examination, were assessed for cognitive and functional abilities, behavioral/psychiatric conditions, and health status at 14-20 month intervals over five assessment cycles. We genotyped these individuals for single-nucleotide polymorphisms (SNPs) in CYP17 and CYP19. Four SNPs in CYP17 were associated with a two and one half-fold increased risk of AD, independent of APOE genotype. Four SNPs in CYP19 were associated with a two-fold increased risk of AD, although three were significant only in those without an APOE ε4 allele. Further, carrying high risk alleles in both CYP17 and CYP19 was associated with an almost four-fold increased risk of AD (OR = 3.8, 95% CI, 1.6-9.5) and elevated sex hormone binding globulin in postmenopausal women. The main effect of the CYP17 and CYP19 variants was to decrease the age at onset. These findings suggest that genes contributing to estrogen bioavailability influence risk of AD in women with DS.

From 'needing to know' to 'needing not to know more': an interpretative phenomenological analysis of couples' experiences with early-onset Alzheimer's disease.

PubMed

Wawrziczny, Emilie; Pasquier, Florence; Ducharme, Francine; Kergoat, Marie-Jeanne; Antoine, Pascal

2016-12-01

To explore the experiences and adjustment modes of couples during the period between the initial signs of the Alzheimer's disease (AD) and the years following diagnosis, particularly in the case of early-onset AD. A dyadic interpretative phenomenological analysis was conducted with married couples in which one member of each couple received a diagnosis of probable early-onset AD (before 65 years of age). Sixteen young couples, followed by the National Reference Centre for Young Persons with AD, agreed to participate. For seven of the couples, the caregiver was a woman. The mean age was 57.4 (SD = 4.2) for the caregivers and 57.3 (SD = 4.1) for the persons with AD. The semi-structured interviews were conducted in the couples' homes. Each interview was conducted with both spouses to capture their interactions in the context of individual and shared experiences. Two higher-order themes emerged from the analyses: the 'need to know' and, after the diagnosis, the 'need not to know more'. Indeed, the first signs mark the beginning of a period of doubt and a search for understanding. This pursuit of knowledge progresses to the recognition of more intense and severe signs that encourage couples to seek medical attention. Both reassuring and destabilising, the diagnosis is a breaking point that modifies how the changes and painful effects associated with disease are experienced. Couples employ strategies to minimise their suffering and consequently their knowledge about the disease. These results show that the couples oscillate between the need to know and the fear of knowing. To protect themselves, they use strategies to reduce their suffering and to distance the disease. The use of these avoidance strategies indicates that certain times in the course of disease management are less appropriate for couples to accept the assistance offered by formal caregivers. © 2015 Nordic College of Caring Science.

Molecular genetics of Alzheimer disease.

PubMed

St George-Hyslop, P H

1999-01-01

Epidemiological and individual case studies indicate that genetic factors play a significant role in the genesis of Alzheimer Disease (AD). To date, molecular genetic studies in families multiply affected with AD have identified three genes (Presenilin 1-PS1, Presenilin 2-PS2, and beta-amyloid precursor protein--betaAPP) associated with highly penetrant early onset AD, and one gene (Apolipoprotein E) associated with late onset AD. A fifth potential AD susceptibility locus has been mapped to a broad region of chromosome 12, but the responsible gene defect has not yet been identified. Case-control studies comparing the frequency of alleles in numerous other candidate genes have identified a number of additional potential AD genes. However, methodological difficulties and conflicting results in follow-up studies, make it unclear whether allelic variations in these genes are truly pathogenic. Nevertheless, analysis of the biochemical effects of mutations in PS1, PS2, betaAPP at least, suggest a common biochemical effect-namely disturbances in the processing of betaAPP protein. In addition to utility in defining potential therapeutic targets, in some circumstances these genes can also potentially be used as adjunctives in clinical presymptomatic, symptomatic or pharmacogenomic diagnosis.

Cognitive Decline in a Colombian Kindred With Autosomal Dominant Alzheimer Disease: A Retrospective Cohort Study.

PubMed

Aguirre-Acevedo, Daniel C; Lopera, Francisco; Henao, Eliana; Tirado, Victoria; Muñoz, Claudia; Giraldo, Margarita; Bangdiwala, Shrikant I; Reiman, Eric M; Tariot, Pierre N; Langbaum, Jessica B; Quiroz, Yakeel T; Jaimes, Fabian

2016-04-01

Data from an autosomal dominant Alzheimer disease (ADAD) kindred were used to track the longitudinal trajectory of cognitive decline associated with preclinical ADAD and explore factors that may modify the rate of cognitive decline. To evaluate the onset and rate of cognitive decline during preclinical ADAD and the effect of socioeconomic, vascular, and genetic factors on the cognitive decline. We performed a retrospective cohort study from January 1, 1995, through June 31, 2012, of individuals from Antioquia, Colombia, who tested positive for the ADAD-associated PSEN1 E280A mutation. Data analysis was performed from August 20, 2014, through November 30, 2015. A mixed-effects model was used to estimate annual rates of change in cognitive test scores and to mark the onset of cognitive decline. Memory, language, praxis, and total scores from the Consortium to Establish a Registry for Alzheimer Disease test battery. Chronologic age was used as a time scale in the models. We explore the effects of sex; educational level; socioeconomic status; residence area; occupation type; marital status; history of hypertension, diabetes mellitus, and dyslipidemia; tobacco and alcohol use; and APOE ε4 on the rates of cognitive decline. A total of 493 carriers met the inclusion criteria and were analyzed. A total of 256 carriers had 2 or more assessments. At the time of the initial assessment, participants had a mean (SD) age of 33.4 (11.7) years and a mean (SD) educational level of 7.2 (4.2) years. They were predominantly female (270 [54.8%]), married (293 [59.4%]), and of low socioeconomic status (322 [65.3%]). Word list recall scores provided the earliest indicator of preclinical cognitive decline at 32 years of age, 12 and 17 years before the kindred's respective median ages at mild cognitive impairment and dementia onset. After the change point, carriers had a statistically significant cognitive decline with a loss of 0.24 (95% CI, -0.26 to -0.22) points per year for the word

The role of novel chitin-like polysaccharides in Alzheimer disease.

PubMed

Castellani, Rudy J; Perry, George; Smith, Mark A

2007-12-01

While controversy over the role of carbohydrates in amyloidosis has existed since the initial recognition of amyloid, current understanding of the role of polysaccharides in the pathogenesis of amyloid deposition of Alzheimer disease and other amyloidoses is limited to studies of glyco-conjugates such as heparin sulfate proteoglycan. We hypothesized that polysaccharides may play a broader role in light of 1) the impaired glucose utilization in Alzheimer disease; 2) the demonstration of amylose in the Alzheimer disease brain; 3) the role of amyloid in Alzheimer disease pathogenesis. Specifically, as with glucose polymers (amyloid), we wanted to explore whether glucosamine polymers such as chitin were being synthesized and deposited as a result of impaired glucose utilization and aberrant hexosamine pathway activation. To this end, using calcofluor histochemistry, we recently demonstrated that amyloid plaques and blood vessels affected by amyloid angiopathy in subjects with sporadic and familial Alzheimer disease elicit chitin-type characteristics. Since chitin is a highly insoluble molecule and a substrate for glycan-protein interactions, chitin-like polysaccharides within the Alzheimer disease brain could provide a scaffolding for amyloid-beta deposition. As such, glucosamine may facilitate the process of amyloidosis, and /or provide neuroprotection in the Alzheimer disease brain.

Racial and ethnic differences among children with new-onset autoimmune Type 1 diabetes.

PubMed

Gandhi, K; Tosur, M; Schaub, R; Haymond, M W; Redondo, M J

2017-10-01

To compare demographic and clinical characteristics among children from ethnic minorities and non-Hispanic white children with new-onset autoimmune Type 1 diabetes. We analysed a single-centre series of 712 children with new-onset autoimmune Type 1 diabetes between January 2008 and March 2011. The median (range) age was 9.7 (0.3-18.1) years, the mean (sd) BMI percentile was 69.7 (25.4) and 48.3% of the cohort were girls. The cohort comprised 57.3% non-Hispanic white, 20.5% Hispanic and 14.8% African-American children, and 7.4% were of other, mixed or unknown race. The Hispanic subgroup, compared with non-Hispanic white subgroup, had a higher mean (sd) C-peptide level [0.82 (1.62) vs 0.55 (0.47) ng/ml; P=0.004), and a greater proportion of children with elevated BMI (overweight or obesity; 49.6% vs 32.5%; P<0.001) and diabetic ketoacidosis (51.8% vs 38.2%; P=0.006). The African-American group had a higher mean (sd) glucose level [24.4 (12.8) vs 21.4 (10.7) mmol/l; P=0.017], a greater proportion of children with ketoacidosis (56.7% vs 38.2%; P=0.001), a greater proportion with elevated BMI (52.9% vs 32.5%; P<0.001), and a lower proportion of children at pre-pubertal stage (49.0% vs 61.6%; P=0.01), and tended to have higher C-peptide levels [0.65 (0.59) vs 0.55 [0.47] ng/ml; P=0.079) compared with the non-Hispanic white children. The differences in C-peptide levels compared with non-Hispanic white children persisted for Hispanic (P=0.01) but not African-American children (P=0.29) after adjustment for age, sex, BMI, ketoacidosis, glucose, Tanner stage and autoantibody number. At the onset of paediatric autoimmune Type 1 diabetes, Hispanic, but not African-American children had higher C-peptide levels, after adjustment for potential confounders, compared with non-Hispanic white children. These findings suggest that ethnicity may contribute to the heterogeneity of Type 1 diabetes pathogenesis, with possible implications for intervention. © 2017 Diabetes UK.

Cystatin C as a risk factor for Alzheimer disease.

PubMed

Cathcart, H M; Huang, R; Lanham, I S; Corder, E H; Poduslo, S E

2005-02-22

Cystatin C, a protease inhibitor with widespread distribution, is upregulated in response to injury. Levels are elevated in the brains of patients with Alzheimer disease (AD). We compared frequencies for the CST 3 exon 1 polymorphism in patients with AD and controls. A proportional odds model indicated that the CST 3 A and APOE4 combination carried a high risk: a 14-fold elevation for men and 16-fold for women. These risks apply to risk at ages older than 64 years and to a shift in onset to ages younger than 65 years.

Quiz: Alzheimer's Disease Quiz | Alzheimer's disease | NIH MedlinePlus the Magazine

MedlinePlus

... of this page please turn Javascript on. Feature: Alzheimer's Disease Quiz: Alzheimer's Disease Quiz Past Issues / Fall 2010 Table of ... How many people in the United States have Alzheimer's disease? as many as 5.1 million as ...

Linkage and mutational analysis of familial Alzheimer disease kindreds for the APP gene region

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kamino, K.; Anderson, L.; O'dahl, S.

1992-11-01

A large number of familial Alzheimer disease (FAD) kindreds were examined to determine whether mutations in the amyloid precursor protein (APP) gene could be responsible for the disease. Previous studies have identified three mutations at APP codon 717 which are pathogenic for Alzheimer disease (AD). Samples from affected subjects were examined for mutations in exons 16 and 17 of the APP gene. A combination of direct sequencing and single-strand conformational polymorphism analysis was used. Sporadic AD and normal controls were also examined by the same methods. Five sequence variants were identified. One variant at APP codon 693 resulted in amore » Glu[yields]Gly change. This is the same codon as the hereditary cerebral hemorrhage with amyloidosis-Dutch type Glu[yields]Gln mutation. Another single-base change at APP codon 708 did not alter the amino acid encoded at this site. Two point mutations and a 6-bp deletion were identified in the intronic sequences surrounding exon 17. None of the variants could be unambigously determined to be responsible for FAD. The larger families were also analyzed by testing for linkage of FAD to a highly polymorphic short tandem repeat marker (D21S210) that is tightly linked to APP. Highly negative LOD scores were obtained for the family groups tested, and linkage was formally excluded beyond [theta] = .10 for the Volga German kindreds, [theta] = .20 for early-onset non-Volga Germans, and [theta] = .10 for late-onset families. LOD scores for linkage of FAD to markers centromeric to APP (D21S1/S11, D21S13, and D21S215) were also negative in the three family groups. These studies show that APP mutations account for AD in only a small fraction of FAD kindreds. 49 refs., 6 figs., 4 tabs.« less

The Role of Cardiovascular Risk Factors and Stroke in Familial Alzheimer Disease

PubMed Central

Tosto, Giuseppe; Bird, Thomas D.; Bennett, David A.; Boeve, Bradley F.; Brickman, Adam M.; Cruchaga, Carlos; Faber, Kelley; Foroud, Tatiana M.; Farlow, Martin; Goate, Alison M.; Graff-Radford, Neill R.; Lantigua, Rafael; Manly, Jennifer; Ottman, Ruth; Rosenberg, Roger; Schaid, Daniel J.; Schupf, Nicole; Stern, Yaakov; Sweet, Robert A.; Mayeux, Richard

2016-01-01

Importance The contribution of cardiovascular disease (CV) and cerebrovascular disease to the risk for late-onset Alzheimer disease (LOAD) has been long debated. Investigations have shown that antecedent CV risk factors increase the risk for LOAD, although other investigations have failed to validate this association. Objective To study the contribution of CV risk factors (type 2 diabetes, hypertension, and heart disease) and the history of stroke to LOAD in a data set of large families multiply affected by LOAD. Design, Setting, and Participants The National Institute on Aging Late-Onset Alzheimer Disease/National Cell Repository for Alzheimer Disease family study (hereinafter referred to as NIA-LOAD study) is a longitudinal study of families with multiple members affected with LOAD. A multiethnic community-based longitudinal study (Washington Heights–Inwood Columbia Aging Project [WHICAP]) was used to replicate findings. The 6553 participants in the NIA-LOAD study were recruited from 23 US Alzheimer disease centers with ongoing data collection since 2003; the 5972 WHICAP participants were recruited at Columbia University with ongoing data collection since 1992. Data analysis was performed from 2003 to 2015. Main Outcomes and Measures Generalized mixed logistic regression models tested the association of CV risk factors (primary association) with LOAD. History of stroke was used for the secondary association. A secondary model adjusted for the presence of an apolipoprotein E (APOE) ε4 allele. A genetic risk score, based on common variants associated with LOAD, was used to account for LOAD genetic risk beyond the APOE ε4 effect. Mediation analyses evaluated stroke as a mediating factor between the primary association and LOAD. Results A total of 6553 NIA-LOAD participants were included in the analyses (4044 women [61.7%]; 2509 men [38.3%]; mean [SD] age, 77.0 [9] years), with 5972 individuals from the WHICAP study included in the replication sample (4072 women

Genetic variants in Alzheimer disease – molecular and brain network approaches

PubMed Central

Gaiteri, Chris; Mostafavi, Sara; Honey, Christopher; De Jager, Philip L.; Bennett, David A.

2016-01-01

Genetic studies in late-onset Alzheimer disease (LOAD) are aimed at identifying core disease mechanisms and providing potential biomarkers and drug candidates to improve clinical care for AD. However, due to the complexity of LOAD, including pathological heterogeneity and disease polygenicity, extracting actionable guidance from LOAD genetics has been challenging. Past attempts to summarize the effects of LOAD-associated genetic variants have used pathway analysis and collections of small-scale experiments to hypothesize functional convergence across several variants. In this review, we discuss how the study of molecular, cellular and brain networks provides additional information on the effect of LOAD-associated genetic variants. We then discuss emerging combinations of omic data types in multiscale models, which provide a more comprehensive representation of the effect of LOAD-associated genetic variants at multiple biophysical scales. Further, we highlight the clinical potential of mechanistically coupling genetic variants and disease phenotypes with multiscale brain models. PMID:27282653

A Bayesian Model for the Prediction and Early Diagnosis of Alzheimer's Disease.

PubMed

Alexiou, Athanasios; Mantzavinos, Vasileios D; Greig, Nigel H; Kamal, Mohammad A

2017-01-01

Alzheimer's disease treatment is still an open problem. The diversity of symptoms, the alterations in common pathophysiology, the existence of asymptomatic cases, the different types of sporadic and familial Alzheimer's and their relevance with other types of dementia and comorbidities, have already created a myth-fear against the leading disease of the twenty first century. Many failed latest clinical trials and novel medications have revealed the early diagnosis as the most critical treatment solution, even though scientists tested the amyloid hypothesis and few related drugs. Unfortunately, latest studies have indicated that the disease begins at the very young ages thus making it difficult to determine the right time of proper treatment. By taking into consideration all these multivariate aspects and unreliable factors against an appropriate treatment, we focused our research on a non-classic statistical evaluation of the most known and accepted Alzheimer's biomarkers. Therefore, in this paper, the code and few experimental results of a computational Bayesian tool have being reported, dedicated to the correlation and assessment of several Alzheimer's biomarkers to export a probabilistic medical prognostic process. This new statistical software is executable in the Bayesian software Winbugs, based on the latest Alzheimer's classification and the formulation of the known relative probabilities of the various biomarkers, correlated with Alzheimer's progression, through a set of discrete distributions. A user-friendly web page has been implemented for the supporting of medical doctors and researchers, to upload Alzheimer's tests and receive statistics on the occurrence of Alzheimer's disease development or presence, due to abnormal testing in one or more biomarkers.

Degree of bilingualism predicts age of diagnosis of Alzheimer's disease in low-education but not in highly educated Hispanics.

PubMed

Gollan, Tamar H; Salmon, David P; Montoya, Rosa I; Galasko, Douglas R

2011-12-01

The current study investigated the relationship between bilingual language proficiency and onset of probable Alzheimer's disease (AD) in 44 Spanish-English bilinguals at the UCSD Alzheimer's Disease Research Center. Degree of bilingualism along a continuum was measured using Boston Naming Test (BNT) scores in each language. Higher degrees of bilingualism were associated with increasingly later age-of-diagnosis (and age of onset of symptoms), but this effect was driven by participants with low education level (a significant interaction between years of education and bilingualism) most of whom (73%) were also Spanish-dominant. Additionally, only objective measures (i.e., BNT scores), not self-reported degree of bilingualism, predicted age-of-diagnosis even though objective and self-reported measures were significantly correlated. These findings establish a specific connection between knowledge of two languages and delay of AD onset, and demonstrate that bilingual effects can be obscured by interactions between education and bilingualism, and by failure to obtain objective measures of bilingualism. More generally, these data support analogies between the effects of bilingualism and "cognitive reserve" and suggest an upper limit on the extent to which reserve can function to delay dementia. Copyright © 2011 Elsevier Ltd. All rights reserved.

Deletion of exons 9 and 10 of the Presenilin 1 gene in a patient with Early-onset Alzheimer Disease generates longer amyloid seeds.

PubMed

Le Guennec, Kilan; Veugelen, Sarah; Quenez, Olivier; Szaruga, Maria; Rousseau, Stéphane; Nicolas, Gaël; Wallon, David; Fluchere, Frédérique; Frébourg, Thierry; De Strooper, Bart; Campion, Dominique; Chávez-Gutiérrez, Lucía; Rovelet-Lecrux, Anne

2017-08-01

Presenilin 1 (PSEN1) mutations are the main cause of autosomal dominant Early-onset Alzheimer Disease (EOAD). Among them, deletions of exon 9 have been reported to be associated with a phenotype of spastic paraparesis. Using exome data from a large sample of 522 EOAD cases and 584 controls to search for genomic copy-number variations (CNVs), we report here a novel partial, in-frame deletion of PSEN1, removing both exons 9 and 10. The patient presented with memory impairment associated with spastic paraparesis, both starting from the age of 56years. He presented a positive family history of EOAD. We performed functional analysis to elucidate the impact of this novel deletion on PSEN1 activity as part of the γ-secretase complex. The deletion does not affect the assembly of a mature protease complex but has an extreme impact on its global endopeptidase activity. The mutant carboxypeptidase-like activity is also strongly impaired and the deleterious mutant effect leads to an incomplete digestion of long Aβ peptides and enhances the production of Aβ43, which has been shown to be potently amyloidogenic and neurotoxic in vivo. Copyright © 2017 Elsevier Inc. All rights reserved.

An Experimental Approach to Detecting Dementia in Down Syndrome: A Paradigm for Alzheimer's Disease

ERIC Educational Resources Information Center

Nelson, Linda D.; Scheibel, Kevin E.; Ringman, John M.; Sayre, James W.

2007-01-01

Measures developed from animal models of aging may detect dementia of the Alzheimer's type in a population at-risk for Alzheimer's disease (AD). Although, by middle age, individuals with Down syndrome (DS) show an extraordinarily high prevalence of AD-type pathology, their severe idiopathic cognitive deficits tend to confound the "clinical"…

Evolution in the conceptualization of dementia and Alzheimer's disease: Greco-Roman period to the 1960s.

PubMed

Berchtold, N C; Cotman, C W

1998-01-01

Most histories of senile dementia commence with Alois Alzheimer's description in 1906 of the first case of Alzheimer's disease, yet the history of senile dementia before 1906 is quite rich, dating back to the ancient Greek and Roman philosophers and physicians. Over the 2500 years since ancient times, the concept of senile dementia has evolved from a rather vague notion that mental decline occurred inevitably in old age, to become defined today by a distinct set of clinical and pathological features with the potential for treatment and prevention within grasp. Throughout history, many elderly individuals with unpredictable behavior were sequestered in institutions, and the line between mental disorders and senile dementia was hazy at best. The identification of Alzheimer's disease at the onset of the 20th century was a turning point for the understanding of senile dementia, and the concepts and histological findings presented by the early researchers of Alzheimer's disease remain relevant still today. Indeed, these early findings are proving to be a continuing source of insight, as many of the issues debated at the turn of the century remain unresolved still today. This paper thus traces the history of the evolution of our current conceptualization of Alzheimer's disease from the amorphous Greco-Roman concept of age-associated dementia.

White Matter Lipids as a Ketogenic Fuel Supply in Aging Female Brain: Implications for Alzheimer's Disease.

PubMed

Klosinski, Lauren P; Yao, Jia; Yin, Fei; Fonteh, Alfred N; Harrington, Michael G; Christensen, Trace A; Trushina, Eugenia; Brinton, Roberta Diaz

2015-12-01

White matter degeneration is a pathological hallmark of neurodegenerative diseases including Alzheimer's. Age remains the greatest risk factor for Alzheimer's and the prevalence of age-related late onset Alzheimer's is greatest in females. We investigated mechanisms underlying white matter degeneration in an animal model consistent with the sex at greatest Alzheimer's risk. Results of these analyses demonstrated decline in mitochondrial respiration, increased mitochondrial hydrogen peroxide production and cytosolic-phospholipase-A2 sphingomyelinase pathway activation during female brain aging. Electron microscopic and lipidomic analyses confirmed myelin degeneration. An increase in fatty acids and mitochondrial fatty acid metabolism machinery was coincident with a rise in brain ketone bodies and decline in plasma ketone bodies. This mechanistic pathway and its chronologically phased activation, links mitochondrial dysfunction early in aging with later age development of white matter degeneration. The catabolism of myelin lipids to generate ketone bodies can be viewed as a systems level adaptive response to address brain fuel and energy demand. Elucidation of the initiating factors and the mechanistic pathway leading to white matter catabolism in the aging female brain provides potential therapeutic targets to prevent and treat demyelinating diseases such as Alzheimer's and multiple sclerosis. Targeting stages of disease and associated mechanisms will be critical.

White Matter Lipids as a Ketogenic Fuel Supply in Aging Female Brain: Implications for Alzheimer's Disease

PubMed Central

Klosinski, Lauren P.; Yao, Jia; Yin, Fei; Fonteh, Alfred N.; Harrington, Michael G.; Christensen, Trace A.; Trushina, Eugenia; Brinton, Roberta Diaz

2015-01-01

White matter degeneration is a pathological hallmark of neurodegenerative diseases including Alzheimer's. Age remains the greatest risk factor for Alzheimer's and the prevalence of age-related late onset Alzheimer's is greatest in females. We investigated mechanisms underlying white matter degeneration in an animal model consistent with the sex at greatest Alzheimer's risk. Results of these analyses demonstrated decline in mitochondrial respiration, increased mitochondrial hydrogen peroxide production and cytosolic-phospholipase-A2 sphingomyelinase pathway activation during female brain aging. Electron microscopic and lipidomic analyses confirmed myelin degeneration. An increase in fatty acids and mitochondrial fatty acid metabolism machinery was coincident with a rise in brain ketone bodies and decline in plasma ketone bodies. This mechanistic pathway and its chronologically phased activation, links mitochondrial dysfunction early in aging with later age development of white matter degeneration. The catabolism of myelin lipids to generate ketone bodies can be viewed as a systems level adaptive response to address brain fuel and energy demand. Elucidation of the initiating factors and the mechanistic pathway leading to white matter catabolism in the aging female brain provides potential therapeutic targets to prevent and treat demyelinating diseases such as Alzheimer's and multiple sclerosis. Targeting stages of disease and associated mechanisms will be critical. PMID:26844268

Decreased Reactivity of Skin Microcirculation in Response to l-Arginine in Later-Onset Type 1 Diabetes

PubMed Central

Neubauer-Geryk, Jolanta; Kozera, Grzegorz M.; Wolnik, Bogumil; Szczyrba, Sebastian; Nyka, Walenty M.; Bieniaszewski, Leszek

2013-01-01

OBJECTIVE The aim of our study was to evaluate the vasodilatory effect of l-arginine infusion on the skin microcirculation and to assess the relationship between this effect and the presence of microangiopathy in patients with type 1 diabetes. RESEARCH DESIGN AND METHODS Capillaroscopy was performed before and after l-arginine infusion in 48 diabetic patients (26 women and 22 men; age, 39.8 ± 6.3 years) and 24 volunteers free of any chronic disease (13 women and 11 men; age, 38.0 ± 6.7 years). The skin microcirculation reactivity, as expressed by the percentage of area covered by capillaries (coverage) and the distance between capillaries (distance), and the relationship between microcirculation reactivity and the presence of microangiopathic complications were assessed. RESULTS The distance before l-arginine infusion was significantly lower in patients than in controls (221 [153–311] vs. 240 [185–356] µm; P = 0.02) and did not differ after l-arginine infusion (223.5 [127–318] vs. 242.5 [181–341] µm; P = 0.27). The difference between the coverage values obtained before and after l-arginine infusion (Δcoverage) was significantly different from zero in the control group but not in the diabetes group. Patients with later onset of diabetes were characterized by decreased skin microcirculation reactivity when compared with patients with earlier onset of diabetes (−1.18 [−5.07 to 11.60] vs. 1.36 [−6.00 to 8.06]; P = 0.02) despite the higher prevalence of retinopathy in patients with earlier onset of diabetes (64% vs. 26%; P = 0.02). CONCLUSIONS Skin microvascular reactivity is impaired in patients with later onset of type 1 diabetes. Capillaroscopy with l-arginine infusion is useful for the identification of skin microangiopathy in type 1 diabetes. PMID:23150282

Apolipoprotein E genotypes do not influence the age of onset in Huntington's disease

PubMed Central

Saft, C; Andrich, J; Brune, N; Gencik, M; Kraus, P; Przuntek, H; Epplen, J

2004-01-01

Objective: The ε4 allele of the apolipoprotein E (ApoE) gene has been defined as a critical factor for early onset neurodegeneration in Pick's, Parkinson's, and Alzheimer's disease. Unexpectedly, the ε4 allele appeared to delay the age of onset in Huntington's disease (HD) patients. Furthermore, sex specific effects were reported on earlier age of onset due to the ApoE ε2ε3 genotype in males with HD. The age of onset of HD is known to be negatively correlated with increasing lengths of pathogenetic CAG expansions in the huntingtin gene. Methods: In order to examine the effects of CAG block lengths, we have correlated ApoE genotypes with the age of onset in 145 patients symptomatic for HD with psychiatric and somatic symptoms (depression, psychosis, dementia, choreic, and other movement disorders) harbouring only modestly expanded huntingtin alleles (41–45 CAGs). Results: The negative correlation between age of onset and CAG block length was established in our HD cohort. Statistically significant effects of the ε4 allele were not obvious regarding clinical characteristics including age of onset, nor were any sex differences for the ε2ε3 genotype observed. Conclusion: The ApoE genotype does not affect the course of HD significantly. PMID:15548484

How longevity research can lead to therapies for Alzheimer's disease: The rapamycin story.

PubMed

Richardson, Arlan; Galvan, Veronica; Lin, Ai-Ling; Oddo, Salvatore

2015-08-01

The discovery that rapamycin increases lifespan in mice and restores/delays many aging phenotypes has led to the speculation that rapamycin has 'anti-aging' properties. The major question discussed in this review is whether a manipulation that has anti-aging properties can alter the onset and/or progression of Alzheimer's disease, a disease in which age is the major risk factor. Rapamycin has been shown to prevent (and possibly restore in some cases) the deficit in memory observed in the mouse model of Alzheimer's disease (AD-Tg) as well as reduce Aβ and tau aggregation, restore cerebral blood flow and vascularization, and reduce microglia activation. All of these parameters are widely recognized as symptoms central to the development of AD. Furthermore, rapamycin has also been shown to improve memory and reduce anxiety and depression in several other mouse models that show cognitive deficits as well as in 'normal' mice. The current research shows the feasibility of using pharmacological agents that increase lifespan, such as those identified by the National Institute on Aging Intervention Testing Program, to treat Alzheimer's disease. Published by Elsevier Inc.

APOEε2 is associated with milder clinical and pathological Alzheimer's disease

PubMed Central

Serrano-Pozo, Alberto; Qian, Jing; Monsell, Sarah E.; Betensky, Rebecca A.; Hyman, Bradley T.

2015-01-01

Objective The Alzheimer disease (AD) APOEε4 risk allele associates with an earlier age of onset and increased amyloid-β deposition, whereas the protective APOEε2 allele delays the onset and appears to prevent amyloid-β deposition. Yet the clinical and pathological effects of APOEε2 remain uncertain because of its relative rarity. We investigated the effects of APOE ε2 and ε4 alleles on AD pathology and cognition in a large US dataset of well characterized AD patients. Methods We studied individuals from the National Alzheimer's Coordinating Center (NACC) autopsy cohort across the entire clinico-pathological continuum of AD. Multivariable models were built to examine the associations between APOE alleles and AD neuropathological changes, using the APOEε3/ε3 group as comparator. Mediation analysis was used to estimate the direct and indirect effects of APOE alleles on AD pathology and cognition (CDR-SOB and MMSE). Results Compared to APOEε3/ε3, APOEε2 is independently associated with lower Braak NFT stages and, possibly, fewer neuritic plaques, but has no direct effect on CAA severity, whereas APOEε4 is associated with more neuritic plaques and CAA, but has no independent effect on Braak NFT stage. Unadjusted analyses showed marked differences among APOE genotypes with respect to cognitive performance (ε2>ε3>ε4). Mediation analysis suggests that this is largely explained through effects on pathology. Interpretation Even when adjusted for age of onset, symptom duration and other demographic variables, APOEε2 is associated with milder AD pathology and less severe antemortem cognitive impairment compared to APOE ε3 and ε4 alleles, suggesting a relative neuroprotective effect of APOEε2 in AD. PMID:25623662

Positional cloning of the chromosome 14 Alzheimer`s disease locus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clark, R.F.; Korenblat, K.M.; Goate, A.M.

1994-09-01

Genetic linkage analysis had indicated a locus for familial early-onset Alzheimer`s disease (FAD) on chromosome 14 at q24.3. The FAD locus has been shown previously to lie between the dinucleotide markers D14S61 and D14S63, a genetic distance of approximately 13 cM. We are currently attempting to identify the gene using a positional cloning strategy. The first step towards the isolation and characterization of this locus was the construction of an overlapping YAC contig covering the entire region. Over forty YACs which map to this region have been isolated from the St. Louis and CEPH libraries by a combination of YACmore » end sequence walking and sequence tagged site mapping. Our contig fully spans the complete domain, encompassing all genetic markers non-recombinant with FAD (i.e. D14S76, D14S43, D14S71, D14S77) and the two nearest flanking FAD-recombinant markers. With restriction mapping of the domain, we can determine the exact size of the region. As a second step, the YACs in this contig are currently being inspected for expressed sequences by exon trapping, initially on those YACs known to be nonchimeric. We have currently made exon-trapped libraries from YACs that have the markers D14S76 and D14S43. Sequence analysis of these libraries indicates that a trapped exon is identified on average for each 30 kb of YAC DNA. The trapped exons are being screened to identify likely candidate genes, which will be examined for mutations in FAD families.« less

Microscopic and macroscopic models for the onset and progression of Alzheimer's disease

NASA Astrophysics Data System (ADS)

Bertsch, Michiel; Franchi, Bruno; Carla Tesi, Maria; Tosin, Andrea

2017-10-01

In the first part of this paper we review a mathematical model for the onset and progression of Alzheimer’s disease (AD) that was developed in subsequent steps over several years. The model is meant to describe the evolution of AD in vivo. In Achdou et al (2013 J. Math. Biol. 67 1369-92) we treated the problem at a microscopic scale, where the typical length scale is a multiple of the size of the soma of a single neuron. Subsequently, in Bertsch et al (2017 Math. Med. Biol. 34 193-214) we concentrated on the macroscopic scale, where brain neurons are regarded as a continuous medium, structured by their degree of malfunctioning. In the second part of the paper we consider the relation between the microscopic and the macroscopic models. In particular we show under which assumptions the kinetic transport equation, which in the macroscopic model governs the evolution of the probability measure for the degree of malfunctioning of neurons, can be derived from a particle-based setting. The models are based on aggregation and diffusion equations for β-Amyloid (Aβ from now on), a protein fragment that healthy brains regularly produce and eliminate. In case of dementia Aβ monomers are no longer properly washed out and begin to coalesce forming eventually plaques. Two different mechanisms are assumed to be relevant for the temporal evolution of the disease: (i) diffusion and agglomeration of soluble polymers of amyloid, produced by damaged neurons; (ii) neuron-to-neuron prion-like transmission. In the microscopic model we consider mechanism (i), modelling it by a system of Smoluchowski equations for the amyloid concentration (describing the agglomeration phenomenon), with the addition of a diffusion term as well as of a source term on the neuronal membrane. At the macroscopic level instead we model processes (i) and (ii) by a system of Smoluchowski equations for the amyloid concentration, coupled to a kinetic-type transport equation for the distribution function of the

Associative memory and its cerebral correlates in Alzheimer׳s disease: evidence for distinct deficits of relational and conjunctive memory.

PubMed

Bastin, Christine; Bahri, Mohamed Ali; Miévis, Frédéric; Lemaire, Christian; Collette, Fabienne; Genon, Sarah; Simon, Jessica; Guillaume, Bénédicte; Diana, Rachel A; Yonelinas, Andrew P; Salmon, Eric

2014-10-01

This study investigated the impact of Alzheimer׳s disease (AD) on conjunctive and relational binding in episodic memory. Mild AD patients and controls had to remember item-color associations by imagining color either as a contextual association (relational memory) or as a feature of the item to be encoded (conjunctive memory). Patients׳ performance in each condition was correlated with cerebral metabolism measured by FDG-PET. The results showed that AD patients had an impaired capacity to remember item-color associations, with deficits in both relational and conjunctive memory. However, performance in the two kinds of associative memory varied independently across patients. Partial Least Square analyses revealed that poor conjunctive memory was related to hypometabolism in an anterior temporal-posterior fusiform brain network, whereas relational memory correlated with metabolism in regions of the default mode network. These findings support the hypothesis of distinct neural systems specialized in different types of associative memory and point to heterogeneous profiles of memory alteration in Alzheimer׳s disease as a function of damage to the respective neural networks. Copyright © 2014 Elsevier Ltd. All rights reserved.

Revisiting DLB Diagnosis: A Consideration of Prodromal DLB and of the Diagnostic Overlap With Alzheimer Disease.

PubMed

McKeith, Ian; Taylor, John-Paul; Thomas, Alan; Donaghy, Paul; Kane, Joseph

2016-09-01

Efforts to clinically diagnose cases having dementia with Lewy bodies (DLB) identify those with a characteristic clinical syndrome (probable DLB) at the expense of missing an equal, if not greater, number of cases who have atypical presentations thought to be associated with coexisting Alzheimer pathologies. This article argues that further efforts should now be made to characterize this atypical group that constitutes cases previously identified postmortem as the Lewy body variant of Alzheimer disease (AD) or as AD with Lewy bodies. Since such fine distinction is unlikely to be achieved on clinical grounds alone, this new diagnostic category will require robust biomarker validation. Turning to a consideration of early/prodromal diagnosis of both typical and atypical DLB cases, it is suggested that there will be at least 3 prototypical forms-a mild cognitive impairment variant, associated with early visuoperceptual and attentional deficits; a delirium onset DLB with provoked or spontaneous delirium as the presenting features; and a psychiatric disorder DLB with its primary presentation as a late-onset affective disorder or psychosis. © The Author(s) 2016.

Study of weak substorms observed during December 8, 1990, geospace environment modeling campaign: Timing of different types of substorm onsets

NASA Astrophysics Data System (ADS)

Mishin, V. M.; Russell, C. T.; Saifudinova, T. I.; Bazarzhapov, A. D.

2000-10-01

We define an expansion onset (synonymous with the main breakup) to be one with sufficient signatures of open tail reconnection. Earlier onsets, which we term initial onsets, occur before the expansion onset, without the signatures of open tail reconnection but with other signs of a clear substorm onset. These two types of substorm onsets and their timing are discussed herein in a study of selected substorm-like events. During the 10-hour interval studied, five impulses of the Perreault-Akasofu index ɛ were observed with comparable peak values. However, the observed magnetospheric responses were very different in terms of equatorward motion and poleward expansion of the auroral oval. We conclude that the occurrence either of an initial onset or of a full onset (under similar boundary conditions) depends on the amount of stored free energy, proportional to the tail length, which is controlled by the input power. The earlier or initial onset marks a sudden change in the convection pattern in the nightside. This onset could mark the initiation of reconnection on closed field lines while the expansion onset could mark the initiation of reconnection on open field lines.

Incidence of complications in young-onset diabetes: Comparing type 2 with type 1 (the young diab study).

PubMed

Amutha, Anandakumar; Anjana, Ranjit Mohan; Venkatesan, Ulagamathesan; Ranjani, Harish; Unnikrishnan, Ranjit; Venkat Narayan, K M; Mohan, Viswanathan; Ali, Mohammed K

2017-01-01

There is little data on the incidence of diabetes complications in young onset type 1 diabetes (T1DM) and type 2 diabetes (T2DM) in non European populations. From a tertiary diabetes centre, Chennai, India, we recruited 108 T1DM (defined by abrupt onset of symptoms or diabetic ketoacidosis, absent insulin reserve requiring insulin treatment) and 90 T2DM participants (defined by absence of ketosis, good beta-cell reserve, and good response to oral agents) who were diagnosed between the ages of 10 and 25years, and without any evidence of diabetes complications at diagnosis. We estimated the incidence of various complications (median follow up of five years); retinopathy was defined by presence of at least one definite microaneurysm by retinal photography, nephropathy by urinary albumin excretion ⩾30μg/mg of creatinine, neuropathy by vibration perception threshold ⩾20V on biothesiometry, peripheral vascular disease by an ankle-brachial index <0.9, and ischemic heart disease (IHD) by history of myocardial infarction or coronary revascularization or Q waves on ECG or on drug treatment for IHD. The mean ages at diagnosis of T1DM and T2DM participants were 17.1±4.2vs. 21.6±3.6years respectively. The incidence of various complications reported in numbers/1000 person years of follow up of T1DM and T2DM were: retinopathy 77.4vs. 78.0/1000 person years, nephropathy, 62.0vs. 58.8, neuropathy 7.8 vs. 13.9 and ischemic heart disease 1.2vs. 5.4. In Cox regression analysis, after adjustment for age, glycated hemoglobin, systolic blood pressure and serum cholesterol, T2DM participants had 2.11 times (95%CI: 1.27-3.51) higher risk of developing any diabetes complication, compared to T1DM. Young-onset T2DM have a more aggressive disease course than T1DM. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

“Noncognitive” symptoms of early Alzheimer disease

PubMed Central

Masters, Mary Clare; Morris, John C.

2015-01-01

Objectives: To observe the natural time course of noncognitive symptoms before the onset of symptomatic Alzheimer disease dementia. Methods: Using the National Alzheimer's Coordinating Center Uniform Data Set from September 2005 to March 2013, data from cognitively normal individuals who were aged 50 years or older at first visit and had subsequent follow-up were analyzed. Survival analyses were used to examine the development of particular symptoms relative to each other on the Neuropsychiatric Inventory Questionnaire (NPI-Q), Functional Activities Questionnaire, and Geriatric Depression Scale, and to compare the development of individual symptoms for persons who did and did not receive a Clinical Dementia Rating (CDR) >0 (indicating abnormal cognition) during the follow-up period. Results: The order of symptom occurrence on the NPI-Q was similar for participants who remained at CDR 0 and for those who received a CDR >0 over the follow-up period, although the time to most NPI-Q symptoms was faster for participants who received a CDR >0 (p < 0.001). With the exception of memory, Geriatric Depression Scale symptoms reported by both CDR groups were similar. Conclusions: We found a significantly earlier presence of positive symptoms on the NPI-Q in cognitively normal patients who subsequently developed CDR >0. Among participants with no depression symptoms at baseline, results suggest that depressive symptoms may increase with aging regardless of incipient dementia. Such findings begin to delineate the noncognitive course of Alzheimer disease dementia in the preclinical stages. Future research must further elucidate the correlation between noncognitive changes and distinct dementia subtypes. PMID:25589671

The Onset of Type 2 Diabetes: Proposal for a Multi-Scale Model

PubMed Central

Tieri, Paolo; De Graaf, Albert; Franceschi, Claudio; Liò, Pietro; Van Ommen, Ben; Mazzà, Claudia; Tuchel, Alexander; Bernaschi, Massimo; Samson, Clare; Colombo, Teresa; Castellani, Gastone C; Capri, Miriam; Garagnani, Paolo; Salvioli, Stefano; Nguyen, Viet Anh; Bobeldijk-Pastorova, Ivana; Krishnan, Shaji; Cappozzo, Aurelio; Sacchetti, Massimo; Morettini, Micaela; Ernst, Marc

2013-01-01

Background Type 2 diabetes mellitus (T2D) is a common age-related disease, and is a major health concern, particularly in developed countries where the population is aging, including Europe. The multi-scale immune system simulator for the onset of type 2 diabetes (MISSION-T2D) is a European Union-funded project that aims to develop and validate an integrated, multilevel, and patient-specific model, incorporating genetic, metabolic, and nutritional data for the simulation and prediction of metabolic and inflammatory processes in the onset and progression of T2D. The project will ultimately provide a tool for diagnosis and clinical decision making that can estimate the risk of developing T2D and predict its progression in response to possible therapies. Recent data showed that T2D and its complications, specifically in the heart, kidney, retina, and feet, should be considered a systemic disease that is sustained by a pervasive, metabolically-driven state of inflammation. Accordingly, there is an urgent need (1) to understand the complex mechanisms underpinning the onset of this disease, and (2) to identify early patient-specific diagnostic parameters and related inflammatory indicators. Objective We aim to accomplish this mission by setting up a multi-scale model to study the systemic interactions of the biological mechanisms involved in response to a variety of nutritional and metabolic stimuli and stressors. Methods Specifically, we will be studying the biological mechanisms of immunological/inflammatory processes, energy intake/expenditure ratio, and cell cycle rate. The overall architecture of the model will exploit an already established immune system simulator as well as several discrete and continuous mathematical methods for modeling of the processes critically involved in the onset and progression of T2D. We aim to validate the predictions of our models using actual biological and clinical data. Results This study was initiated in March 2013 and is expected

Convergent genetic and expression data implicate immunity in Alzheimer's disease

PubMed Central

Jones, Lesley; Lambert, Jean-Charles; Wang, Li-San; Choi, Seung-Hoan; Harold, Denise; Vedernikov, Alexey; Escott-Price, Valentina; Stone, Timothy; Richards, Alexander; Bellenguez, Céline; Ibrahim-Verbaas, Carla A; Naj, Adam C; Sims, Rebecca; Gerrish, Amy; Jun, Gyungah; DeStefano, Anita L; Bis, Joshua C; Beecham, Gary W; Grenier-Boley, Benjamin; Russo, Giancarlo; Thornton-Wells, Tricia A; Jones, Nicola; Smith, Albert V; Chouraki, Vincent; Thomas, Charlene; Ikram, M Arfan; Zelenika, Diana; Vardarajan, Badri N; Kamatani, Yoichiro; Lin, Chiao-Feng; Schmidt, Helena; Kunkle, Brian; Dunstan, Melanie L; Ruiz, Agustin; Bihoreau, Marie-Thérèse; Reitz, Christiane; Pasquier, Florence; Hollingworth, Paul; Hanon, Olivier; Fitzpatrick, Annette L; Buxbaum, Joseph D; Campion, Dominique; Crane, Paul K; Becker, Tim; Gudnason, Vilmundur; Cruchaga, Carlos; Craig, David; Amin, Najaf; Berr, Claudine; Lopez, Oscar L; De Jager, Philip L; Deramecourt, Vincent; Johnston, Janet A; Evans, Denis; Lovestone, Simon; Letteneur, Luc; Kornhuber, Johanes; Tárraga, Lluís; Rubinsztein, David C; Eiriksdottir, Gudny; Sleegers, Kristel; Goate, Alison M; Fiévet, Nathalie; Huentelman, Matthew J; Gill, Michael; Emilsson, Valur; Brown, Kristelle; Kamboh, M Ilyas; Keller, Lina; Barberger-Gateau, Pascale; McGuinness, Bernadette; Larson, Eric B; Myers, Amanda J; Dufouil, Carole; Todd, Stephen; Wallon, David; Love, Seth; Kehoe, Pat; Rogaeva, Ekaterina; Gallacher, John; George-Hyslop, Peter St; Clarimon, Jordi; Lleὀ, Alberti; Bayer, Anthony; Tsuang, Debby W; Yu, Lei; Tsolaki, Magda; Bossù, Paola; Spalletta, Gianfranco; Proitsi, Petra; Collinge, John; Sorbi, Sandro; Garcia, Florentino Sanchez; Fox, Nick; Hardy, John; Naranjo, Maria Candida Deniz; Razquin, Cristina; Bosco, Paola; Clarke, Robert; Brayne, Carol; Galimberti, Daniela; Mancuso, Michelangelo; Moebus, Susanne; Mecocci, Patrizia; del Zompo, Maria; Maier, Wolfgang; Hampel, Harald; Pilotto, Alberto; Bullido, Maria; Panza, Francesco; Caffarra, Paolo; Nacmias, Benedetta; Gilbert, John R; Mayhaus, Manuel; Jessen, Frank; Dichgans, Martin; Lannfelt, Lars; Hakonarson, Hakon; Pichler, Sabrina; Carrasquillo, Minerva M; Ingelsson, Martin; Beekly, Duane; Alavarez, Victoria; Zou, Fanggeng; Valladares, Otto; Younkin, Steven G; Coto, Eliecer; Hamilton-Nelson, Kara L; Mateo, Ignacio; Owen, Michael J; Faber, Kelley M; Jonsson, Palmi V; Combarros, Onofre; O'Donovan, Michael C; Cantwell, Laura B; Soininen, Hilkka; Blacker, Deborah; Mead, Simon; Mosley, Thomas H; Bennett, David A; Harris, Tamara B; Fratiglioni, Laura; Holmes, Clive; de Bruijn, Renee FAG; Passmore, Peter; Montine, Thomas J; Bettens, Karolien; Rotter, Jerome I; Brice, Alexis; Morgan, Kevin; Foroud, Tatiana M; Kukull, Walter A; Hannequin, Didier; Powell, John F; Nalls, Michael A; Ritchie, Karen; Lunetta, Kathryn L; Kauwe, John SK; Boerwinkle, Eric; Riemenschneider, Matthias; Boada, Mercè; Hiltunen, Mikko; Martin, Eden R; Pastor, Pau; Schmidt, Reinhold; Rujescu, Dan; Dartigues, Jean-François; Mayeux, Richard; Tzourio, Christophe; Hofman, Albert; Nöthen, Markus M; Graff, Caroline; Psaty, Bruce M; Haines, Jonathan L; Lathrop, Mark; Pericak-Vance, Margaret A; Launer, Lenore J; Farrer, Lindsay A; van Duijn, Cornelia M; Van Broekhoven, Christine; Ramirez, Alfredo; Schellenberg, Gerard D; Seshadri, Sudha; Amouyel, Philippe; Holmans, Peter A

2015-01-01

Background Late–onset Alzheimer's disease (AD) is heritable with 20 genes showing genome wide association in the International Genomics of Alzheimer's Project (IGAP). To identify the biology underlying the disease we extended these genetic data in a pathway analysis. Methods The ALIGATOR and GSEA algorithms were used in the IGAP data to identify associated functional pathways and correlated gene expression networks in human brain. Results ALIGATOR identified an excess of curated biological pathways showing enrichment of association. Enriched areas of biology included the immune response (p = 3.27×10-12 after multiple testing correction for pathways), regulation of endocytosis (p = 1.31×10-11), cholesterol transport (p = 2.96 × 10-9) and proteasome-ubiquitin activity (p = 1.34×10-6). Correlated gene expression analysis identified four significant network modules, all related to the immune response (corrected p 0.002 – 0.05). Conclusions The immune response, regulation of endocytosis, cholesterol transport and protein ubiquitination represent prime targets for AD therapeutics. PMID:25533204

Convergent genetic and expression data implicate immunity in Alzheimer's disease.

PubMed

2015-06-01

Late-onset Alzheimer's disease (AD) is heritable with 20 genes showing genome-wide association in the International Genomics of Alzheimer's Project (IGAP). To identify the biology underlying the disease, we extended these genetic data in a pathway analysis. The ALIGATOR and GSEA algorithms were used in the IGAP data to identify associated functional pathways and correlated gene expression networks in human brain. ALIGATOR identified an excess of curated biological pathways showing enrichment of association. Enriched areas of biology included the immune response (P = 3.27 × 10(-12) after multiple testing correction for pathways), regulation of endocytosis (P = 1.31 × 10(-11)), cholesterol transport (P = 2.96 × 10(-9)), and proteasome-ubiquitin activity (P = 1.34 × 10(-6)). Correlated gene expression analysis identified four significant network modules, all related to the immune response (corrected P = .002-.05). The immune response, regulation of endocytosis, cholesterol transport, and protein ubiquitination represent prime targets for AD therapeutics. Copyright © 2015. Published by Elsevier Inc.

Science Signaling Podcast for 10 May 2016: PKCα in Alzheimer's disease.

PubMed

Newton, Alexandra C; Tanzi, Rudolph E; VanHook, Annalisa M

2016-05-10

This Podcast features an interview with Alexandra Newton and Rudolph Tanzi, authors of a Research Article that appears in the 10 May 2016 issue of Science Signaling, about activating mutations in protein kinase Cα that may promote the type of neural defects that characterize Alzheimer's disease. Alzheimer's disease is a progressive neurodegenerative disorder that causes cognitive loss and, eventually, death. Alzheimer's disease is characterized by the accumulation of amyloid-β (Aβ), synaptic depression, and synaptic degeneration. Alfonso et al found activating mutations in the gene encoding protein kinase Cα (PKCα) in some families with inherited Alzheimer's disease. Loss of PKCα function prevented Aβ-induced synaptic depression in brain tissue from mice, suggesting that activated forms of PKCα may contribute to Alzheimer's disease in some patients.Listen to Podcast. Copyright © 2016, American Association for the Advancement of Science.

ADAM10 as a therapeutic target for brain diseases: from developmental disorders to Alzheimer's disease.

PubMed

Marcello, Elena; Borroni, Barbara; Pelucchi, Silvia; Gardoni, Fabrizio; Di Luca, Monica

2017-11-01

In the central nervous system a disintegrin and metalloproteinase 10 (ADAM10) controls several functions such as neurodevelopment, synaptic plasticity and dendritic spine morphology thanks to its activity towards a high number of substrates, including the synaptic cell adhesion molecules as the Amyloid Precursor Protein, N-cadherin, Notch and Ephrins. In particular, ADAM10 plays a key role in the modulation of the molecular mechanisms responsible for dendritic spine formation, maturation and stabilization and in the regulation of the molecular organization of the glutamatergic synapse. Consequently, an alteration of ADAM10 activity is strictly correlated to the onset of different types of synaptopathies, ranging from neurodevelopmental disorders, i.e. autism spectrum disorders, to neurodegenerative diseases, i.e. Alzheimer's Disease. Areas covered: We describe the most recent discoveries in understanding of the role of ADAM10 activity at the glutamatergic excitatory synapse and its involvement in the onset of neurodevelopmental and neurodegenerative disorders. Expert opinion: A progress in the understanding of the molecular mechanisms driving ADAM10 activity at synapses and its alterations in brain disorders is the first step before designing a specific drug able to modulate ADAM10 activity.

7 Warning Signs of Alzheimer's | Alzheimer's disease | NIH MedlinePlus the Magazine

MedlinePlus

... please turn Javascript on. Feature: Alzheimer's Disease 7 Warning Signs of Alzheimer's Past Issues / Fall 2010 Table ... is to alert the public to the early warning signs of Alzheimer's disease. If someone has several ...

Reduced penetrance of the PSEN1 H163Y autosomal dominant Alzheimer mutation: a 22-year follow-up study.

PubMed

Thordardottir, Steinunn; Rodriguez-Vieitez, Elena; Almkvist, Ove; Ferreira, Daniel; Saint-Aubert, Laure; Kinhult-Ståhlbom, Anne; Thonberg, Håkan; Schöll, Michael; Westman, Eric; Wall, Anders; Eriksdotter, Maria; Zetterberg, Henrik; Blennow, Kaj; Nordberg, Agneta; Graff, Caroline

2018-05-10

The range of onset ages within some PSEN1 families is wide, and a few cases of reduced penetrance of PSEN1 mutations have been reported. However, published data on reduced penetrance have been limited to clinical histories, often collected retrospectively and lacking biomarker information. We present a case of reduced penetrance of the PSEN1 H163Y mutation in a carrier prospectively followed for 22 years. Two brothers (A and B), both carriers of the H163Y mutation, were followed between 1995 and 2017. They underwent repeated clinical evaluations, neuropsychological assessments, and cerebrospinal fluid analyses, as well as brain imaging examinations with structural magnetic resonance, [ 18 F]fluorodeoxyglucose positron emission tomography, and [ 11 C]Pittsburgh compound B positron emission tomography. Brother A was followed between 44 and 64 years of age. Cognitive symptoms due to Alzheimer's disease set in at the age of 54. Gradual worsening of symptoms resulted in admittance to a nursing home owing to dependence on others for all activities of daily living. He showed a curvilinear decline in cognitive function on neuropsychological tests, and changes on magnetic resonance imaging, positron emission tomography, and biomarkers in the cerebrospinal fluid supported a clinical diagnosis of Alzheimer's disease. Brother A died at the age of 64 and fulfilled the criteria for definitive Alzheimer's disease according to neuropathological examination results. Brother B was followed between the ages of 43 and 65 and showed no cognitive deterioration on repeated neuropsychological test occasions. In addition, no biomarker evidence of Alzheimer's disease pathology was detected, either on imaging examinations or in cerebrospinal fluid. The average (SD) age of symptom onset for PSEN1 H163Y is 51 ± 7 years according to previous studies. However, we present a case of a biomarker-verified reduction in penetrance in a mutation carrier who was still symptom-free at the age of

[Alzheimer's Therapeutic Research Institute].

PubMed

Shimada, Hiroyuki; Kato, Yuichi; Fujii, Hisako; Mori, Hiroshi

2017-07-01

The Alzheimer's Therapeutic Research Institute (ATRI) was established in 2015 after ATRI director, Paul Aisen, and his fellow experts in therapeutic interventions for Alzheimer's disease (AD) moved from the Alzheimer's Disease Cooperative Study (ADCS) at the University of California to the Keck School of Medicine of the University of Southern California. The National Institute on Aging (NIA) decided to commit $14 million to the ATRI via an Alzheimer's Clinical Trials Consortium (ACTC). The ATRI supports various studies such as the Anti-Amyloid Treatment in Asymptomatic Alzheimer's study ("A4 study"), Alzheimer's Disease Neuroimaging Initiative 3 (ADNI3), Longitudinal Evaluation of Amyloid Risk and Neurodegeneration (LEARN), and The Alzheimer's Disease Neuroimaging Initiative-Depression Project (ADNI-D). The ATRI will share all relevant data and materials with the academic community, corporations, and government organizations. The ATRI is overseen by a Data and Safety Monitoring Board (DSMB), which comprises of leading experts in the field of Alzheimer's research and acts independently. The ATRI is slated to play a central role in clinical dementia research in the US in near future.

Molecular basis for increased risk for late-onset Alzheimer disease due to the naturally occurring L28P mutation in apolipoprotein E4.

PubMed

Argyri, Letta; Dafnis, Ioannis; Theodossiou, Theodossis A; Gantz, Donald; Stratikos, Efstratios; Chroni, Angeliki

2014-05-02

The apolipoprotein (apo) E4 isoform has consistently emerged as a susceptibility factor for late-onset Alzheimer disease (AD), although the exact mechanism is not clear. A rare apoE4 mutant, apoE4[L28P] Pittsburgh, burdens carriers with an added risk for late-onset AD and may be a useful tool for gaining insights into the role of apoE4 in disease pathogenesis. Toward this end, we evaluated the effect of the L28P mutation on the structural and functional properties of apoE4. ApoE4[L28P] was found to have significantly perturbed thermodynamic properties, to have reduced helical content, and to expose a larger portion of the hydrophobic surface to the solvent. Furthermore, this mutant is thermodynamically destabilized and more prone to proteolysis. When interacting with lipids, apoE4[L28P] formed populations of lipoprotein particles with structural defects. The structural perturbations brought about by the mutation were accompanied by aberrant functions associated with the pathogenesis of AD. Specifically, apoE4[L28P] promoted the cellular uptake of extracellular amyloid β peptide 42 (Aβ42) by human neuroblastoma SK-N-SH cells as well as by primary mouse neuronal cells and led to increased formation of intracellular reactive oxygen species that persisted for at least 24 h. Furthermore, lipoprotein particles containing apoE4[L28P] induced intracellular reactive oxygen species formation and reduced SK-N-SH cell viability. Overall, our findings suggest that the L28P mutation leads to significant structural and conformational perturbations in apoE4 and can induce functional defects associated with neuronal Aβ42 accumulation and oxidative stress. We propose that these structural and functional changes underlie the observed added risk for AD development in carriers of apoE4[L28P].

Neurocognitive differential diagnosis of dementing diseases: Alzheimer's Dementia, Vascular Dementia, Frontotemporal Dementia, and Major Depressive Disorder.

PubMed

Braaten, Alyssa J; Parsons, Thomas D; McCue, Robert; Sellers, Alfred; Burns, William J

2006-11-01

Similarities in presentation of Dementia of Alzheimer's Type, Vascular Dementia, Frontotemporal Dementia, and Major Depressive Disorder, pose differential diagnosis challenges. The current study identifies specific neuropsychological patterns of scores for Dementia of Alzheimer's Type, Vascular Dementia, Frontotemporal Dementia, and Major Depressive Disorder. Neuropsychological domains directly assessed in the study included: immediate memory, delayed memory, confrontational naming, verbal fluency, attention, concentration, and executive functioning. The results reveal specific neuropsychological comparative profiles for Dementia of Alzheimer's Type, Vascular Dementia, Frontotemporal Dementia, and Major Depressive Disorder. The identification of these profiles will assist in the differential diagnosis of these disorders and aid in patient treatment.

Natural Products based P-glycoprotein Activators for Improved β-amyloid Clearance in Alzheimer's Disease: An in silico Approach.

PubMed

Shinde, Pravin; Vidyasagar, Nikhil; Dhulap, Sivakami; Dhulap, Abhijeet; Hirwani, Raj

2015-01-01

Alzheimer's disease is an age related disorder and is defined to be progressive, irreversible neurodegenerative disease. The potential targets which are associated with the Alzheimer's disease are cholinesterases, N-methyl-D-aspartate receptor, Beta secretase 1, Pregnane X receptor (PXR) and P-glycoprotein (Pgp). P-glycoprotein is a member of the ATP binding cassette (ABC) transporter family, which is an important integral of the blood-brain, blood-cerebrospinal fluid and the blood-testis barrier. Reports from the literature provide evidences that the up-regulation of the efflux pump is liable for a decrease in β -amyloid intracellular accumulation and is an important hallmark in Alzheimer's disease (AD). Thus, targeting β-amyloid clearance by stimulating Pgp could be a useful strategy to prevent Alzheimer's advancement. Currently available drugs provide limited effectiveness and do not assure to cure Alzheimer's disease completely. On the other hand, the current research is now directed towards the development of synthetic or natural based therapeutics which can delay the onset or progression of Alzheimer's disease. Since ancient time medicinal plants such as Withania somnifera, Bacopa monieri, Nerium indicum have been used to prevent neurological disorders including Alzheimer's disease. Till today around 125 Indian medicinal plants have been screened on the basis of ethnopharmacology for their activity against neurological disorders. In this paper, we report bioactives from natural sources which show binding affinity towards the Pgp receptor using ligand based pharmacophore development, virtual screening, molecular docking and molecular dynamics simulation studies for the bioactives possessing acceptable ADME properties. These bioactives can thus be useful to treat Alzheimer's disease.

Alzheimer's Association

MedlinePlus

... Get involved Last Updated: Our vision is a world without Alzheimer's Formed in 1980, the Alzheimer's Association ... your eyes while supporting our vision of a world without Alzheimer’s. Sunglasses Wear purple on The Longest ...

Childhood adversity, early-onset depressive/anxiety disorders, and adult-onset asthma.

PubMed

Scott, Kate M; Von Korff, Michael; Alonso, Jordi; Angermeyer, Matthias C; Benjet, Corina; Bruffaerts, Ronny; de Girolamo, Giovanni; Haro, Josep Maria; Kessler, Ronald C; Kovess, Viviane; Ono, Yutaka; Ormel, Johan; Posada-Villa, José

2008-11-01

To investigate a) whether childhood adversity predicts adult-onset asthma; b) whether early-onset depressive/anxiety disorders predict adult-onset asthma; and c) whether childhood adversity and early-onset depressive/anxiety disorders predict adult-onset asthma independently of each other. Previous research has suggested, but not established, that childhood adversity may predict adult-onset asthma and, moreover, that the association between mental disorders and asthma may be a function of shared risk factors, such as childhood adversity. Ten cross-sectional population surveys of household-residing adults (>18 years, n = 18,303) assessed mental disorders with the Composite International Diagnostic Interview (CIDI 3.0) as part of the World Mental Health surveys. Assessment of a range of childhood family adversities was included. Asthma was ascertained by self-report of lifetime diagnosis and age of diagnosis. Survival analyses calculated hazard ratios (HRs) for risk of adult-onset (>age 20 years) asthma as a function of number and type of childhood adversities and early-onset (onset asthma with risk increasing with the number of adversities experienced (HRs = 1.49-1.71). Early-onset depressive and anxiety disorders also predicted adult-onset asthma (HRs = 1.67-2.11). Childhood adversities and early-onset depressive and anxiety disorders both predicted adult-onset asthma after mutual adjustment (HRs = 1.43-1.91). Childhood adversities and early-onset depressive/anxiety disorders independently predict adult-onset asthma, suggesting that the mental disorder-asthma relationship is not a function of a shared background of childhood adversity.

[Premorbid psychological processes in patients with Alzheimer's disease and in patients with vascular dementia].

PubMed

Bauer, J; Stadtmüller, G; Qualmann, J; Bauer, H

1995-01-01

We analyzed the premorbid biographies of 21 patients with Alzheimer's disease for possible common features. Eleven age-matched patients suffering from vascular dementia served as a control group. The observations from our qualitative study indicate that persons with a conflict-avoiding, submissive, premorbid personality predominate among Alzheimer patients. Persons who later became Alzheimer patients tended to leave important daily-life decisions to their partners (or other persons of reference). Prior to the onset of the very first neuropsychological deficits, persons who later became Alzheimer patients were found to stay in a lasting situation in which they were subject to a treatment that could be designated as "caring tutelage." Subsequently, most patients became subject to an increasingly patronizing and restricting treatment. Further elements that were frequently found as part of the premorbid development were physical or psychological burden, loss of social contacts, and loss of motivation. In contrast, assertive and dominant premorbid traits predominated in the group of vascular patients. The premorbid biographical situation of persons who later became vascular patients was characterized by a loss of the control which these persons had hitherto exerted over partners, their families, or the situation at their working place. We advance the hypothesis that in Alzheimer's disease the described psychological phenomena are part of a preclinical process, during which biological, psychological, and social factors interact, finally joining into the clinical stage of the disease. Possibilities for psychotherapeutic interventions are discussed.

The clinical characteristics of patients with mitochondrial tRNA Leu(UUR)m.3243A > G mutation: Compared with type 1 diabetes and early onset type 2 diabetes.

PubMed

Zhu, Jie; Yang, Peng; Liu, Xiang; Yan, Li; Rampersad, Sharvan; Li, Feng; Li, Hong; Sheng, Chunjun; Cheng, Xiaoyun; Zhang, Manna; Qu, Shen

2017-08-01

This study presents nine patients with mitochondrial tRNA Leu (UUR) m.3243A>G mutation and compares the clinical characteristics and diabetes complications with type 1 diabetes (T1DM) or early onset type 2 diabetes (T2DM). The study covers 9 patients with MIDD, 33 patients with T1DM and 86 patients (age of onset ≤35years) with early onset T2DM, matched for sex, age at onset of diabetes, duration of diabetes. All patients with MIDD were confirmed as carrying the m.3243A>G mitochondrial DNA mutation. Serum HbA1c, beta-cell function, retinal and renal complications of diabetes, bone metabolic markers, lumbar spine and femoral neck BMD bone mineral density were compared to characterize the clinical features of all patients. Nine patients were from five unrelated families, and the mean (SD) onset age of those patients was 31.2±7.2year. Two patients required insulin at presentation, and six patients progressed to insulin requirement after a mean of 7.2years. β-Cell function in the MIDD group was intermediate between T1DM and early-onset T2DM. In MIDD, four patients were diagnosed as diabetic retinopathy (4/9) and five patients (5/9) had macroalbuminuria. The number of patients with diabetic retinopathy and macroalbuminuria in the MIDD group was comparable to T1DM or early-onset T2DM. The rate of osteoporosis (BMD T-score<-2.5 SD) in the patient with MIDD was higher than the T1DM or early-onset T2DM group. Our study indicates that of the nine subjects with MIDD, three patients (1-II-1, 1-II-3, 1-II-4) who came from the same family had a history of acute pancreatitis. Compared with T1DM or early-onset T2DM matched for sex, age, duration of diabetes, MIDD patients had the highest rate of osteoporosis. Copyright © 2017 Elsevier Inc. All rights reserved.

Corticotropin-releasing factor receptor-1 antagonism mitigates beta amyloid pathology and cognitive and synaptic deficits in a mouse model of Alzheimer's disease.

PubMed

Zhang, Cheng; Kuo, Ching-Chang; Moghadam, Setareh H; Monte, Louise; Campbell, Shannon N; Rice, Kenner C; Sawchenko, Paul E; Masliah, Eliezer; Rissman, Robert A

2016-05-01

Stress and corticotropin-releasing factor (CRF) have been implicated as mechanistically involved in Alzheimer's disease (AD), but agents that impact CRF signaling have not been carefully tested for therapeutic efficacy or long-term safety in animal models. To test whether antagonism of the type-1 corticotropin-releasing factor receptor (CRFR1) could be used as a disease-modifying treatment for AD, we used a preclinical prevention paradigm and treated 30-day-old AD transgenic mice with the small-molecule, CRFR1-selective antagonist, R121919, for 5 months, and examined AD pathologic and behavioral end points. R121919 significantly prevented the onset of cognitive impairment in female mice and reduced cellular and synaptic deficits and beta amyloid and C-terminal fragment-β levels in both genders. We observed no tolerability or toxicity issues in mice treated with R121919. CRFR1 antagonism presents a viable disease-modifying therapy for AD, recommending its advancement to early-phase human safety trials. Copyright © 2015 Alzheimer's Association. All rights reserved.

Serial PIB and MRI in normal, mild cognitive impairment and Alzheimer's disease: implications for sequence of pathological events in Alzheimer's disease.

PubMed

Jack, Clifford R; Lowe, Val J; Weigand, Stephen D; Wiste, Heather J; Senjem, Matthew L; Knopman, David S; Shiung, Maria M; Gunter, Jeffrey L; Boeve, Bradley F; Kemp, Bradley J; Weiner, Michael; Petersen, Ronald C

2009-05-01

The purpose of this study was to use serial imaging to gain insight into the sequence of pathologic events in Alzheimer's disease, and the clinical features associated with this sequence. We measured change in amyloid deposition over time using serial (11)C Pittsburgh compound B (PIB) positron emission tomography and progression of neurodegeneration using serial structural magnetic resonance imaging. We studied 21 healthy cognitively normal subjects, 32 with amnestic mild cognitive impairment and 8 with Alzheimer's disease. Subjects were drawn from two sources--ongoing longitudinal registries at Mayo Clinic, and the Alzheimer's disease Neuroimaging Initiative (ADNI). All subjects underwent clinical assessments, MRI and PIB studies at two time points, approximately one year apart. PIB retention was quantified in global cortical to cerebellar ratio units and brain atrophy in units of cm(3) by measuring ventricular expansion. The annual change in global PIB retention did not differ by clinical group (P = 0.90), and although small (median 0.042 ratio units/year overall) was greater than zero among all subjects (P < 0.001). Ventricular expansion rates differed by clinical group (P < 0.001) and increased in the following order: cognitively normal (1.3 cm(3)/year) < amnestic mild cognitive impairment (2.5 cm(3)/year) < Alzheimer's disease (7.7 cm(3)/year). Among all subjects there was no correlation between PIB change and concurrent change on CDR-SB (r = -0.01, P = 0.97) but some evidence of a weak correlation with MMSE (r =-0.22, P = 0.09). In contrast, greater rates of ventricular expansion were clearly correlated with worsening concurrent change on CDR-SB (r = 0.42, P < 0.01) and MMSE (r =-0.52, P < 0.01). Our data are consistent with a model of typical late onset Alzheimer's disease that has two main features: (i) dissociation between the rate of amyloid deposition and the rate of neurodegeneration late in life, with amyloid deposition proceeding at a constant slow

Insulin therapy at onset of type 2 diabetes mellitus--a new concept.

PubMed

Sahay, B K

2011-04-01

In this study, insulin therapy was initiated at onset of disease in patients whose fasting blood glucose was more than 250 mg/dl. All enrolled subjects were treated with human premixed insulin (30/70) administered subcutaneously twice daily before breakfast and before dinner. A total of 113 subjects entered the study fulfilling the inclusion criteria. Good glycaemic control was achieved in a few days. The dosage requirement of insulin came down gradually after control was achieved as manifest by hypoglycaemia--leading to withdrawal of insulin. Some of them were managed with diet and exercise alone. Others required small doses of oral antidiabetic agents (OAD). There were no cases of secondary failure to OADs. Ten cases are on average duration of follow-up of 10 years. Two cases are under good control with diet and exercise alone, seven on treatment with oral hypoglycemic agents and one of them requiring insulin to maintain HbAlc below 7%. Thus insulin therapy at onset provides an opportunity to correct all the underlying pathogenic mechanisms, i.e., glucotoxicity, lipotoxicity and prevents beta cell apoptosis and suppresses inflammation, leading to beta cell protection. Such timely intervention provides long term benefits, laying the foundation for the concept of beta cell preservation rather that only replacing beta cell function. Hence we propose that all patients with type 2 diabetes should be offered insulin therapy at the onset of their diabetes for a period of 2-4 weeks.

Type 2 diabetes and/or its treatment leads to less cognitive impairment in Alzheimer's disease patients.

PubMed

Domínguez, Raúl O; Marschoff, Enrique R; González, Silvia E; Repetto, Marisa G; Serra, Jorge A

2012-10-01

To evaluate the cognitive performance of a homogeneous population of Alzheimer's disease (AD), non-demented Type 2 Diabetes Mellitus (DIAB), demented with concomitant diseases (AD+DIAB) and healthy control subjects. AD is a progressive dementia disorder characterized clinically by impairment of memory, cognition and behavior. Recently, a major research interest in AD has been placed on early evaluation. Diabetes is one of the clinical conditions that represent the greatest risk of developing oxidative stress and dementia. Glucose overload, leading to the development of impaired-induced insulin secretion in DIAB and has been suggested to slow or deter AD pathogenesis. The degree of cognitive impairment was determined on the Alzheimer Disease Assessment Scale-Cognitive (ADAS-Cog) and the Folstein's Mini Mental State Examination (MMSE); the severity of dementia was quantified applying the Clinical Dementia Rating (CDR) test; the Hamilton test was employed to evaluate depressive conditions; the final population studied was 101 subjects. The cognitive deterioration is statistically significantly lower (p<0.05) in AD+DIAB patients as compared with AD patients. In this longitudinal study the superimposed diabetic condition was associated with a lower rate of cognitive decline, while diabetic non-demented patients and controls present normal scores. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Averting Dementia of the Alzheimer's Type in Women: Can Counselors Help?

ERIC Educational Resources Information Center

Douthit, Kathryn Z.

2007-01-01

Alzheimer's disease (AD) is the most common cause of dementia in late life, taking its greatest toll on women over age 80. This article provides an overview of AD, including risk factors and counseling strategies targeting risk. Counseling strategies address stress, cardiovascular health, social integration, depression, and holistic wellness.

Medication for Alzheimer's disease and associated fall hazard: a retrospective cohort study from the Alzheimer's Disease Neuroimaging Initiative.

PubMed

Epstein, Noam U; Guo, Rong; Farlow, Martin R; Singh, Jaswinder P; Fisher, Morris

2014-02-01

Falls are common in the elderly, especially in those with cognitive impairment. The elderly are often treated with several medications, which may have both beneficial and deleterious effects. The use and type of medication in Alzheimer's disease (AD) patients and association with falls is limited. We examined the association between falls and medication use in the Alzheimer's Disease Neuroimaging Initiative (ADNI). Diagnosis, demographics, medication use, apolipoprotein E4 allele status and functional activity level at baseline were gathered for 810 participants enrolled in the ADNI, including healthy controls and subjects with mild cognitive impairment or Alzheimer's. Reports detailing adverse event falls were tabulated. Baseline characteristics were compared between subjects with and without one or more falls. Cox proportional hazards models were conducted to evaluate the association between subject characteristics and hazard of the first fall. Age (p < 0.0001), Functional Activities Questionnaire (p = 0.035), Beers List (p = 0.0477) and medications for treating cognitive symptoms of Alzheimer's (p = 0.0019) were associated with hazard of fall in the univariate model. In the final multivariate model, after adjusting for covariates, Alzheimer's medication use (p = 0.0005) was associated with hazard of fall. Medication was changed by the clinician after an adverse fall event in 9% of the falls. About 7% of the falls were reported as serious adverse events and 6% were reported to be severe. We found a significant association between the use of symptomatic medication treating cognitive symptoms in AD and hazard of fall after adjusting for age and Beers List medication use. Additional pharmacovigilance of the association between falls and Alzheimer's medication use is warranted.

[Initial deficits in Alzheimer's disease: 3 practical examples].

PubMed

Jódar-Vicente, M

The aim of the first studies to determine the neuropsychological features of Alzheimer's disease (AD) were based on the concept of the disease as an homogeneous entity. However, clinical observations and the most recent research studies have demonstrated that Alzheimer's disease may present several other neuropsychological deficits on its clinical onset. in the initial process of cognitive function loss, memory deficits are seen as a consequence of hippocampal degeneration; however, a great interindividual variability is observed in the appearance of other cortical deficits. In addiction, new advances in epidemiology, neurochemistry and neuropathology support the idea that AD represents a neuropsychologically heterogeneous disorder. In AD three different subgroups have been established: patients with initial deficits in visuospatial abilities, patients with a major deterioration of linguistic abilities, and a third group with altered visuospatial and linguistic abilities. The most sensitive neuropsychological tests capable of distinguish among these differences were The Boston Naming Test (BNT) and the copy of a drawing. These results have been confirmed with single photon emission computed tomography (SPECT) images, and has been observed that patients with a pattern of a elevated right-hemispheric deterioration presented also a higher right-hipofunctionality. At the same time, patients with an elevated linguistic deficit showed a higher hipofunctionality image in the left hemisphere. In this work we present three patients from a prospective study in course, who have similar background, education, gender and disease evolution, but with an onset of the illness corresponding to each of the patterns previously described All three patients were explored with an extense neuropsychological battery of tests specially chosen for this study.

Gender-specific association of ATP-binding cassette transporter 1 (ABCA1) polymorphisms with the risk of late-onset Alzheimer's disease.

PubMed

Sundar, Purnima Desai; Feingold, Eleanor; Minster, Ryan L; DeKosky, Steven T; Kamboh, M Ilyas

2007-06-01

Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder caused by a complex interaction of genetic and environmental factors. Increasing evidence highlights a potential role for cholesterol in the pathophysiology of AD. The ABCA1 gene, located in close vicinity to the 9q linkage peaks identified by genome-wide AD linkage studies, plays an important role in cellular cholesterol efflux, and is likely a good candidate gene. However, results from published genetic association studies between ABCA1 and AD are ambiguous. In the present study, we examined the role of two ABCA1 polymorphisms, R219K (rs2230806) and G-17C (rs2740483) in modifying the risk of late-onset AD (LOAD) in a large American white cohort of 992 AD cases and 699 controls. We observed significant gender x R219K interaction (p=0.00008). Female carriers of the 219K allele showed a 1.75-fold increased risk of developing AD compared to non-219K carrier females (95% CI 1.34-2.29; p=0.00004). The overall two-site haplotype distribution was also significant between female AD cases and controls (p=0.017). The risk associated with the R219K polymorphism was independent of the recently reported significant association in the ubiquilin (UBQLN1) gene in this region on chromosome 9q. Our data suggest a gender-specific and APOE and UBQLN1 independent association between the ABCA1/R219K polymorphism and LOAD.

Communication of brain network core connections altered in behavioral variant frontotemporal dementia but possibly preserved in early-onset Alzheimer's disease

NASA Astrophysics Data System (ADS)

Daianu, Madelaine; Jahanshad, Neda; Mendez, Mario F.; Bartzokis, George; Jimenez, Elvira E.; Thompson, Paul M.

2015-03-01

Diffusion imaging and brain connectivity analyses can assess white matter deterioration in the brain, revealing the underlying patterns of how brain structure declines. Fiber tractography methods can infer neural pathways and connectivity patterns, yielding sensitive mathematical metrics of network integrity. Here, we analyzed 1.5-Tesla wholebrain diffusion-weighted images from 64 participants - 15 patients with behavioral variant frontotemporal dementia (bvFTD), 19 with early-onset Alzheimer's disease (EOAD), and 30 healthy elderly controls. Using whole-brain tractography, we reconstructed structural brain connectivity networks to map connections between cortical regions. We evaluated the brain's networks focusing on the most highly central and connected regions, also known as hubs, in each diagnostic group - specifically the "high-cost" structural backbone used in global and regional communication. The high-cost backbone of the brain, predicted by fiber density and minimally short pathways between brain regions, accounted for 81-92% of the overall brain communication metric in all diagnostic groups. Furthermore, we found that the set of pathways interconnecting high-cost and high-capacity regions of the brain's communication network are globally and regionally altered in bvFTD, compared to healthy participants; however, the overall organization of the high-cost and high-capacity networks were relatively preserved in EOAD participants, relative to controls. Disruption of the major central hubs that transfer information between brain regions may impair neural communication and functional integrity in characteristic ways typical of each subtype of dementia.

Loss-of-Function PCSK9 Mutations Are Not Associated With Alzheimer Disease.

PubMed

Paquette, Martine; Saavedra, Yascara Grisel Luna; Poirier, Judes; Théroux, Louise; Dea, Doris; Baass, Alexis; Dufour, Robert

2018-03-01

Hypercholesterolemia is a major risk factor for the late-onset form of Alzheimer disease (AD). Loss-of-function (LOF) mutations of PCSK9 and PCSK9 inhibitors lower low-density lipoprotein cholesterol (LDL-C) and have been associated with a reduced risk of cardiovascular disease. The aim of this study was to examine the effect of PCSK9 LOF variants on risk and age of onset of AD. A total of 878 participants (410 controls and 468 AD cases) from the Quebec Founder Population were included in the study. Fifty-four (6.2%) participants carried the R46L mutation, whereas 226 (26.2%) participants carried the InsLEU mutation. There was no protective or no deleterious effect of carrying PCSK9 LOF mutations on AD prevalence nor on age of onset, even when stratified by apolipoprotein E epsilon 4 genotype or by gender. Our data indicate that carrying PCSK9 LOF mutations has a neutral effect on neurocognitive health and the prevalence of AD.

Assessing the presence of shared genetic architecture between Alzheimer's disease and major depressive disorder using genome-wide association data

PubMed Central

Gibson, J; Russ, T C; Adams, M J; Clarke, T-K; Howard, D M; Hall, L S; Fernandez-Pujals, A M; Wigmore, E M; Hayward, C; Davies, G; Murray, A D; Smith, B H; Porteous, D J; Deary, I J; McIntosh, A M

2017-01-01

Major depressive disorder (MDD) and Alzheimer's disease (AD) are both common in older age and frequently co-occur. Numerous phenotypic studies based on clinical diagnoses suggest that a history of depression increases risk of subsequent AD, although the basis of this relationship is uncertain. Both illnesses are polygenic, and shared genetic risk factors could explain some of the observed association. We used genotype data to test whether MDD and AD have an overlapping polygenic architecture in two large population-based cohorts, Generation Scotland's Scottish Family Health Study (GS:SFHS; N=19 889) and UK Biobank (N=25 118), and whether age of depression onset influences any relationship. Using two complementary techniques, we found no evidence that the disorders are influenced by common genetic variants. Using linkage disequilibrium score regression with genome-wide association study (GWAS) summary statistics from the International Genomics of Alzheimer's Project, we report no significant genetic correlation between AD and MDD (rG=−0.103, P=0.59). Polygenic risk scores (PRS) generated using summary data from International Genomics of Alzheimer's Project (IGAP) and the Psychiatric Genomics Consortium were used to assess potential pleiotropy between the disorders. PRS for MDD were nominally associated with participant-recalled AD family history in GS:SFHS, although this association did not survive multiple comparison testing. AD PRS were not associated with depression status or late-onset depression, and a survival analysis showed no association between age of depression onset and genetic risk for AD. This study found no evidence to support a common polygenic structure for AD and MDD, suggesting that the comorbidity of these disorders is not explained by common genetic variants. PMID:28418403

Assessing the presence of shared genetic architecture between Alzheimer's disease and major depressive disorder using genome-wide association data.

PubMed

Gibson, J; Russ, T C; Adams, M J; Clarke, T-K; Howard, D M; Hall, L S; Fernandez-Pujals, A M; Wigmore, E M; Hayward, C; Davies, G; Murray, A D; Smith, B H; Porteous, D J; Deary, I J; McIntosh, A M

2017-04-18

Major depressive disorder (MDD) and Alzheimer's disease (AD) are both common in older age and frequently co-occur. Numerous phenotypic studies based on clinical diagnoses suggest that a history of depression increases risk of subsequent AD, although the basis of this relationship is uncertain. Both illnesses are polygenic, and shared genetic risk factors could explain some of the observed association. We used genotype data to test whether MDD and AD have an overlapping polygenic architecture in two large population-based cohorts, Generation Scotland's Scottish Family Health Study (GS:SFHS; N=19 889) and UK Biobank (N=25 118), and whether age of depression onset influences any relationship. Using two complementary techniques, we found no evidence that the disorders are influenced by common genetic variants. Using linkage disequilibrium score regression with genome-wide association study (GWAS) summary statistics from the International Genomics of Alzheimer's Project, we report no significant genetic correlation between AD and MDD (r G =-0.103, P=0.59). Polygenic risk scores (PRS) generated using summary data from International Genomics of Alzheimer's Project (IGAP) and the Psychiatric Genomics Consortium were used to assess potential pleiotropy between the disorders. PRS for MDD were nominally associated with participant-recalled AD family history in GS:SFHS, although this association did not survive multiple comparison testing. AD PRS were not associated with depression status or late-onset depression, and a survival analysis showed no association between age of depression onset and genetic risk for AD. This study found no evidence to support a common polygenic structure for AD and MDD, suggesting that the comorbidity of these disorders is not explained by common genetic variants.

Knowledge of Alzheimer's disease among Vietnamese Americans and correlates of their knowledge about Alzheimer's disease.

PubMed

Lee, Sang E; Casado, Banghwa Lee

2017-01-01

The present study examined the knowledge of Alzheimer's disease and correlates of the disease knowledge among Vietnamese Americans. Cross-sectional survey interviews were conducted with 95 middle-aged and older Vietnamese Americans. Vietnamese Americans showed limited knowledge about Alzheimer's disease. Normalization of Alzheimer's disease in old age was prevalent. They lacked knowledge about treatment and cure of Alzheimer's disease. Those who reside longer in the U.S. and are more exposed to Alzheimer's disease are likely to have higher levels of Alzheimer's disease knowledge. Our study identified current Alzheimer's disease knowledge level and status, and areas of misconceptions and knowledge gaps among Vietnamese Americans, calling for urgent needs for educational outreach to improve knowledge about Alzheimer's disease among Vietnamese Americans. Information about who can be more or less knowledgeable about Alzheimer's disease can be used to strategize and tailor outreach efforts for different segments of the Vietnamese American population.

A Deeper Look into Type 1 Diabetes – Imaging Immune Responses during Onset of Disease

PubMed Central

Christoffersson, Gustaf; von Herrath, Matthias G.

2016-01-01

Cytotoxic T lymphocytes execute the killing of insulin-producing beta cells during onset of type 1 diabetes mellitus (T1D). The research community has come far in dissecting the major events in the development of this disease, but still the trigger and high-resolved information of the immunological events leading up to beta cell loss are missing. During the past decades, intravital imaging of immune responses has led to significant scientific breakthroughs in diverse models of disease, including T1D. Dynamic imaging of immune cells at the pancreatic islets during T1D onset has been made possible through the development of both advanced microscopes, and animal models that allow long-term immobilization of the pancreas. The use of these modalities has revealed a milling microenvironment at the pancreatic islets during disease onset with a plethora of active players. Clues to answering the remaining questions in this disease may lie in intravital imaging, including how key immune cells traffic to and from the pancreas, and how cells interact at this target tissue. This review highlights and discusses recent studies, models, and techniques focused to understand the immune responses during T1D onset through intravital imaging. PMID:27574523

Replication of CLU, CR1, and PICALM associations with alzheimer disease.

PubMed

Carrasquillo, Minerva M; Belbin, Olivia; Hunter, Talisha A; Ma, Li; Bisceglio, Gina D; Zou, Fanggeng; Crook, Julia E; Pankratz, V Shane; Dickson, Dennis W; Graff-Radford, Neill R; Petersen, Ronald C; Morgan, Kevin; Younkin, Steven G

2010-08-01

To test for replication of the association between variants in the CLU, CR1, and PICALM genes with Alzheimer disease. Follow-up case-control association study. The Mayo Clinics at Jacksonville, Florida, and Rochester, Minnesota. Community-based patients of European descent with late-onset Alzheimer disease (LOAD) and controls without dementia who were seen at the Mayo clinics, and autopsy-confirmed cases and controls whose pathology was evaluated at the Mayo Clinic in Jacksonville. Additional samples were obtained from the National Cell Repository for Alzheimer Disease (NCRAD). A total of 1829 LOAD cases and 2576 controls were analyzed. The most significant single-nucleotide polymorphisms in CLU (rs11136000), CR1 (rs3818361), and PICALM (rs3851179) were tested for allelic association with LOAD. Main Outcome Measure Clinical or pathology-confirmed diagnosis of LOAD. Odds ratios for CLU, CR1, and PICALM were 0.82, 1.15, and 0.80, respectively, comparable in direction and magnitude with those originally reported. P values were 8.6 x 10(-5), .014, and 1.3 x 10(-5), respectively; they remain significant even after Bonferroni correction for the 3 single-nucleotide polymorphisms tested. These results show near-perfect replication and provide the first additional evidence that CLU, CR1, and PICALM are associated with the risk of LOAD.

Bariatric surgery may reduce the risk of Alzheimer's diseases through GLP-1 mediated neuroprotective effects.

PubMed

Keshava, Hari B; Mowla, Ashkan; Heinberg, Leslie J; Schauer, Philip R; Brethauer, Stacy A; Aminian, Ali

2017-07-01

Obesity and diabetes are associated with deficits in multiple neurocognitive domains and increased risk for dementia. Over the last two decades, there has been a significant increase in bariatric and metabolic surgery worldwide, driven by rising intertwined pandemics of obesity and diabetes, along with improvement in surgical techniques. Patients undergoing bariatric surgery achieve a significant decrease in their excess weight and a multitude of sequela associated with obesity, diabetes, and metabolic syndrome. Glucagon-like peptide 1 (GLP-1) is an intestinal peptide that has been implicated as one of the weight loss-independent mechanisms in how bariatric surgery affects type 2 diabetes. GLP-1 improves insulin secretion, inhibits apoptosis and induce pancreatic islet neogenesis, promotes satiety, and can regulate heart rate and blood pressure. Moreover, numerous studies have demonstrated potential neuroprotective and neurotrophic effects of GLP-1. Increased GLP-1 activity has been shown to increase cortical activity, promote neuronal growth, and inhibit neuronal degeneration. Specifically, in experimental studies on Alzheimer's disease, GLP-1 decreases amyloid deposition and neurofibrillary tangles. Furthermore, recent studies have also suggested that GLP-1 based therapies, new class of antidiabetic drugs, have favorable effects on neurodegenerative disorders such as Alzheimer's disease. We present a hypothesis that bariatric surgery can help delay or even prevent the onset of Alzheimer's disease in long-term by increasing the levels of GLP-1. This hypothesis has a potential for many studies from basic science projects to large population studies to fully understand the neurological and cognitive consequences of bariatric surgery and associated rise in GLP-1. Copyright © 2017 Elsevier Ltd. All rights reserved.

SAPS-associated explosive brightening on the dusk-side: A new type of onset-like disturbance: A new type of onset-like disturbance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Henderson, M. G.; Morley, S. K.; Kepko, L. E.

Quasi-periodic energetic particle injections have been observed at geosynchronous orbit on the dusk-side during a steady magnetospheric convection event. Here, we examine high resolution auroral imager data and ground magnetometer data associated with the first of these injections and conclude that it was not associated with classical substorm signatures. It is proposed that these injections are caused by the explosive non-linear growth of a shear-flow-ballooning instability in the region where sub-auroral polarization streams (SAPS) also occur. It is suggested that interchange will occur preferentially in the low-conductivity SAPS region since the magnetic Richardson number is lowest there and the ‘line-tying’more » effect will also be least stabilizing there. We also propose that the observed particle injection signatures and auroral morphology constitute a new type of SAPS-associated explosive ‘onset-like’ disturbance that can occur during intervals of strong convection.« less

SAPS-associated explosive brightening on the dusk-side: A new type of onset-like disturbance: A new type of onset-like disturbance

DOE PAGES

Henderson, M. G.; Morley, S. K.; Kepko, L. E.

2017-12-06

Quasi-periodic energetic particle injections have been observed at geosynchronous orbit on the dusk-side during a steady magnetospheric convection event. Here, we examine high resolution auroral imager data and ground magnetometer data associated with the first of these injections and conclude that it was not associated with classical substorm signatures. It is proposed that these injections are caused by the explosive non-linear growth of a shear-flow-ballooning instability in the region where sub-auroral polarization streams (SAPS) also occur. It is suggested that interchange will occur preferentially in the low-conductivity SAPS region since the magnetic Richardson number is lowest there and the ‘line-tying’more » effect will also be least stabilizing there. We also propose that the observed particle injection signatures and auroral morphology constitute a new type of SAPS-associated explosive ‘onset-like’ disturbance that can occur during intervals of strong convection.« less

Clinical trials in predementia stages of Alzheimer disease.

PubMed

Pillai, Jagan A; Cummings, Jeffrey L

2013-05-01

Effective treatments of Alzheimer disease (AD) dementia are an urgent necessity. There is a growing consensus that effective disease-modifying treatment before the onset of clinical dementia and slowing the progression of mild symptoms are needed after recent setbacks in AD therapeutics. The identification of at-risk and preclinical AD populations is becoming important for targeting primary and secondary prevention clinical trials in AD. This article reviews the strategies and challenges in targeting at-risk and preclinical AD populations for a new generation of AD clinical trials. Design, outcome measures, and complexities in successfully completing a clinical trial targeting this population are reviewed. Copyright © 2013 Elsevier Inc. All rights reserved.

On cognitive ecology and the environmental factors that promote Alzheimer disease: lessons from Octodon degus (Rodentia: Octodontidae).

PubMed

Rivera, Daniela S; Inestrosa, Nibaldo C; Bozinovic, Francisco

2016-02-20

Cognitive ecologist posits that the more efficiently an animal uses information from the biotic and abiotic environment, the more adaptive are its cognitive abilities. Nevertheless, this approach does not test for natural neurodegenerative processes under field or experimental conditions, which may recover animals information processing and decision making and may explain, mechanistically, maladaptive behaviors. Here, we call for integrative approaches to explain the relationship between ultimate and proximate mechanisms behind social behavior. We highlight the importance of using the endemic caviomorph rodent Octodon degus as a valuable natural model for mechanistic studies of social behavior and to explain how physical environments can shape social experiences that might influence impaired cognitive abilities and the onset and progression of neurodegenerative disorders such as Alzheimer disease. We consequently suggest neuroecological approaches to examine how key elements of the environment may affect neural and cognitive mechanisms associated with learning, memory processes and brain structures involved in social behavior. We propose the following three core objectives of a program comprising interdisciplinary research in O. degus, namely: (1) to determine whether diet types provided after weaning can lead to cognitive impairment associated with spatial memory, learning and predisposing to develop Alzheimer disease in younger ages; (2) to examine if early life social experience has long term effects on behavior and cognitive responses and risk for development Alzheimer disease in later life and (3) To determine if an increase of social interactions in adult degu reared in different degree of social stressful conditions alter their behavior and cognitive responses.

Alzheimer's disease: An acquired neurodegenerative laminopathy.

PubMed

Frost, Bess

2016-05-03

The nucleus is typically depicted as a sphere encircled by a smooth surface of nuclear envelope. For most cell types, this depiction is accurate. In other cell types and in some pathological conditions, however, the smooth nuclear exterior is interrupted by tubular invaginations of the nuclear envelope, often referred to as a "nucleoplasmic reticulum," into the deep nuclear interior. We have recently reported a significant expansion of the nucleoplasmic reticulum in postmortem human Alzheimer's disease brain tissue. We found that dysfunction of the nucleoskeleton, a lamin-rich meshwork that coats the inner nuclear membrane and associated invaginations, is causal for Alzheimer's disease-related neurodegeneration in vivo. Additionally, we demonstrated that proper function of the nucleoskeleton is required for survival of adult neurons and maintaining genomic architecture. Here, we elaborate on the significance of these findings in regard to pathological states and physiological aging, and discuss cellular causes and consequences of nuclear envelope invagination.

Extracellular neurofibrillary tangles associated with degenerating neurites and neuropil threads in Alzheimer-type dementia.

PubMed

Yamaguchi, H; Nakazato, Y; Kawarabayashi, T; Ishiguro, K; Ihara, Y; Morimatsu, M; Hirai, S

1991-01-01

We examined the cellular components of extracellular neurofibrillary tangles (E-NFT) in the hippocampal areas in cases with Alzheimer-type dementia. Immunohistochemically, the E-NFT were labeled for the C terminus of tau and glial fibrillary acidic protein. Moreover, the majority of the E-NFT was associated with intensely argyrophilic rods and with tau- and ubiquitin-immunoreactive dots. Ultrastructurally, the E-NFT consisted mainly of extracellular paired helical filaments (PHF) and astroglial processes. The extracellular PHF tended to be straighter and thinner. One third of the E-NFT was associated with small degenerating neurites containing many dense bodies and with neuropil threads containing PHF. These findings suggested that extracellular PHF promote both intense astroglial reaction and neuritic alteration, and that the E-NFT are continuously changing their morphology.

The genetics of Alzheimer disease: back to the future.

PubMed

Bertram, Lars; Lill, Christina M; Tanzi, Rudolph E

2010-10-21

Three decades of genetic research in Alzheimer disease (AD) have substantially broadened our understanding of the pathogenetic mechanisms leading to neurodegeneration and dementia. Positional cloning led to the identification of rare, disease-causing mutations in APP, PSEN1, and PSEN2 causing early-onset familial AD, followed by the discovery of APOE as the single most important risk factor for late-onset AD. Recent genome-wide association approaches have delivered several additional AD susceptibility loci that are common in the general population, but exert only very small risk effects. As a result, a large proportion of the heritability of AD continues to remain unexplained by the currently known disease genes. It seems likely that much of this "missing heritability" may be accounted for by rare sequence variants, which, owing to recent advances in high-throughput sequencing technologies, can now be assessed in unprecedented detail. Copyright © 2010 Elsevier Inc. All rights reserved.

The Alzheimer's Disease Mitochondrial Cascade Hypothesis: Progress and Perspectives

PubMed Central

Swerdlow, Russell H.; Burns, Jeffrey M.; Khan, Shaharyar M.

2013-01-01

Ten years ago we first proposed the Alzheimer's disease (AD) mitochondrial cascade hypothesis. This hypothesis maintains gene inheritance defines an individual's baseline mitochondrial function; inherited and environmental factors determine rates at which mitochondrial function changes over time; and baseline mitochondrial function and mitochondrial change rates influence AD chronology. Our hypothesis unequivocally states in sporadic, late-onset AD, mitochondrial function affects amyloid precursor protein (APP) expression, APP processing, or beta amyloid (Aβ) accumulation and argues if an amyloid cascade truly exists, mitochondrial function triggers it. We now review the state of the mitochondrial cascade hypothesis, and discuss it in the context of recent AD biomarker studies, diagnostic criteria, and clinical trials. Our hypothesis predicts biomarker changes reflect brain aging, new AD definitions clinically stage brain aging, and removing brain Aβ at any point will marginally impact cognitive trajectories. Our hypothesis, therefore, offers unique perspective into what sporadic, late-onset AD is and how to best treat it. PMID:24071439

Ketosis Onset Type 2 Diabetes Had Better Islet β-Cell Function and More Serious Insulin Resistance

PubMed Central

Lu, Hongyun; Hu, Fang; Zeng, Yingjuan; Zou, Lingling; Luo, Shunkui; Sun, Ying; Liu, Hong; Sun, Liao

2014-01-01

Diabetic ketosis had been identified as a characteristic of type 1 diabetes mellitus (T1DM), but now emerging evidence has identified that they were diagnosed as T2DM after long time follow up. This case control study was aimed at comparing the clinical characteristic, β-cell function, and insulin resistance of ketosis and nonketotic onset T2DM and providing evidence for treatment selection. 140 cases of newly diagnosed T2DM patients were divided into ketosis (62 cases) and nonketotic onset group (78 cases). After correction of hyperglycemia and ketosis with insulin therapy, plasma C-peptide concentrations were measured at 0, 0.5, 1, 2, and 3 hours after 75 g glucose oral administration. Area under the curve (AUC) of C-peptide was calculated. Homoeostasis model assessment was used to estimate basal β-cell function (HOMA-β) and insulin resistance (HOMA-IR). Our results showed that ketosis onset group had higher prevalence of nonalcoholic fatty liver disease (NAFLD) than nonketotic group (P = 0.04). Ketosis onset group had increased plasma C-peptide levels at 0 h, 0.5 h, and 3 h and higher AUC0–0.5, AUC0–1, AUC0–3 (P < 0.05). Moreover, this group also had higher HOMA-β and HOMA-IR than nonketotic group (P < 0.05). From these data, we concluded that ketosis onset T2DM had better islet β-cell function and more serious insulin resistance than nonketotic onset T2DM. PMID:24829925

A population-based study of familial Alzheimer disease: linkage to chromosomes 14, 19, and 21.

PubMed

van Duijn, C M; Hendriks, L; Farrer, L A; Backhovens, H; Cruts, M; Wehnert, A; Hofman, A; Van Broeckhoven, C

1994-10-01

Linkage of Alzheimer disease (AD) to DNA markers on chromosomes 14, 19, and 21 was studied in 10 families in which the disease was apparently inherited as an autosomal dominant trait. Families were derived from a Dutch population-based epidemiologic study of early-onset AD. Although in all probands the onset of AD was at or before age 65 years, the mean age at onset was after age 65 years in four families (referred to as "LOAD"). Among the six families with early-onset AD (referred to as "EOAD," i.e., mean age of onset of AD of relatives was at or before age 65 years), conclusive linkage to 14q24.3 was found in one family with a very early onset (around 47 years), while linkage to the same region was excluded in two other families. For the LOAD families, predominantly negative lod scores were obtained, and the overall lod score excluded linkage to chromosome 14. The results with markers on chromosome 19 and chromosome 21 were not conclusive for EOAD and LOAD. The findings of our study confirm genetic heterogeneity within familial EOAD.

Do MCI criteria in drug trials accurately identify subjects with predementia Alzheimer's disease?

PubMed Central

Visser, P; Scheltens, P; Verhey, F

2005-01-01

Background: Drugs effective in Alzheimer-type dementia have been tested in subjects with mild cognitive impairment (MCI) because these are supposed to have Alzheimer's disease in the predementia stage. Objectives: To investigate whether MCI criteria used in these drug trials can accurately diagnose subjects with predementia Alzheimer's disease. Methods: MCI criteria of the Gal-Int 11 study, InDDEx study, ADCS memory impairment study, ampakine CX 516 study, piracetam study, and Merck rofecoxib study were applied retrospectively in a cohort of 150 non-demented subjects from a memory clinic. Forty two had progressed to Alzheimer type dementia during a five year follow up period and were considered to have predementia Alzheimer's disease at baseline. Outcome measures were the odds ratio, sensitivity, specificity, and positive and negative predictive value. Results: The odds ratio of the MCI criteria for predementia Alzheimer's disease varied between 0.84 and 11. Sensitivity varied between 0.46 and 0.83 and positive predictive value between 0.43 and 0.76. None of the criteria combined a high sensitivity with a high positive predictive value. Exclusion criteria for depression led to an increase in positive predictive value and specificity at the cost of sensitivity. In subjects older than 65 years the positive predictive value was higher than in younger subjects. Conclusions: The diagnostic accuracy of MCI criteria used in trials for predementia Alzheimer's disease is low to moderate. Their use may lead to inclusion of many patients who do not have predementia Alzheimer's disease or to exclusion of many who do. Subjects with moderately severe depression should not be excluded from trials in order not to reduce the sensitivity. PMID:16170074

No association of dynamin binding protein (DNMBP) gene SNPs and Alzheimer's disease.