Medicine and Health Sciences Commons^™

Distinct Patterns Of Default Mode And Executive Control Network Circuitry Contribute To Present And Future Executive Function In Older Adults, Christopher A. Brown, Frederick A. Schmitt, Charles D. Smith, Brian T. Gold

Neuroscience Faculty Publications

Executive function (EF) performance in older adults has been linked with functional and structural profiles within the executive control network (ECN) and default mode network (DMN), white matter hyperintensities (WMH) burden and levels of Alzheimer's disease (AD) pathology. Here, we simultaneously explored the unique contributions of these factors to baseline and longitudinal EF performance in older adults. Thirty-two cognitively normal (CN) older adults underwent neuropsychological testing at baseline and annually for three years. Neuroimaging and AD pathology measures were collected at baseline. Separate linear regression models were used to determine which of these variables predicted composite EF scores at baseline …

Motivators For Alzheimer's Disease Clinical Trial Participation, Shoshana H. Bardach, Sarah D. Holmes, Gregory A. Jicha

Graduate Center for Gerontology Faculty Publications

Background

Alzheimer’s disease (AD) research progress is impeded due to participant recruitment challenges. This study seeks to better understand, from the perspective of individuals engaged in clinical trials (CTs), research motivations.

Methods

Participants, or their caregivers, from AD treatment and prevention CTs were surveyed about research motivators.

Results

The 87 respondents had a mean age of 72.2, were predominantly Caucasian, 55.2% were male, and 56.3% had cognitive impairment. An overwhelming majority rated the potential to help themselves or a loved one and the potential to help others in the future as important motivators. Relatively few respondents were motivated by free …

Treated Hypothyroidism Is Associated With Cerebrovascular Disease But Not Alzheimer's Disease Pathology In Older Adults, Willa D. Brenowitz, Fang Han, Walter A. Kukull, Peter T. Nelson

Pathology and Laboratory Medicine Faculty Publications

Thyroid hormone (TH) disease is common among older adults and is associated with cognitive impairment. However, pathologic correlates are not well understood. We studied pathologic and clinical factors associated with hypothyroidism, the most common form of TH disease, in research subjects seen annually for clinical evaluations at U.S. Alzheimer’s Disease Centers. Thyroid disease and treatment status were assessed during clinician interviews. Among autopsied subjects, there were 555 participants with treated hypothyroidism and 2,146 with no known thyroid disease; hypothyroidism was associated with severe atherosclerosis (OR=1.35 95% CI: 1.02, 1.79) but not Alzheimer’s disease (AD) pathologies (amyloid plaques or neurofibrillary tangles). …

Clinically Silent Alzheimer's And Vascular Pathologies Influence Brain Networks Supporting Executive Function In Healthy Older Adults, Brian T. Gold, Christopher A. Brown, Jonathan G. Hakun, Leslie M. Shaw, John Q. Trojanowski, Charles D. Smith

Neuroscience Faculty Publications

Aging is associated with declines in executive function. We examined how executive functional brain systems are influenced by clinically silent Alzheimer’s disease (AD) pathology and cerebral white matter hyperintensities (WMHs). Twenty-nine younger adults and thirty-four cognitively normal older adults completed a working memory paradigm while functional magnetic resonance imaging (fMRI) was performed. Older adults further underwent lumbar cerebrospinal fluid (CSF) draw for assessment of AD pathology and FLAIR imaging for assessment of WMHs. Accurate working memory performance in both age groups was associated with high fronto-visual functional connectivity (fC). However, in older adults, higher expression of fronto-visual fC was linked …

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

Biostatistics Faculty Publications

Introduction—We sought to determine whether a systems biology approach may identify novel late-onset Alzheimer's disease (LOAD) loci.

Methods—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.

Results—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 …

Transcriptional Signatures Of Brain Aging And Alzheimer's Disease: What Are Our Rodent Models Telling Us?, Kendra E. Hargis, Eric M. Blalock

Pharmacology and Nutritional Sciences Faculty Publications

Aging is the biggest risk factor for idiopathic Alzheimer’s disease (AD). Recently, the National Institutes of Health released AD research recommendations that include: appreciating normal brain aging, expanding data-driven research, using open-access resources, and evaluating experimental reproducibility. Transcriptome data sets for aging and AD in humans and animal models are available in NIH-curated, publically accessible databases. However, little work has been done to test for concordance among those molecular signatures. Here, we test the hypothesis that brain transcriptional profiles from animal models recapitulate those observed in the human condition. Raw transcriptional profile data from twenty-nine studies were analyzed to produce …

Calcium's Role As Nuanced Modulator Of Cellular Physiology In The Brain, Hilaree N. Frazier, Shaniya Maimaiti, Katie L. Anderson, Lawrence D. Brewer, John C. Gant, Nada M. Porter, Olivier Thibault

Pharmacology and Nutritional Sciences Faculty Publications

Neuroscientists studying normal brain aging, spinal cord injury, Alzheimer’s disease (AD) and other neurodegenerative diseases have focused considerable effort on carefully characterizing intracellular perturbations in calcium dynamics or levels. At the cellular level, calcium is known for controlling life and death and orchestrating most events in between. For many years, intracellular calcium has been recognized as an essential ion associated with nearly all cellular functions from cell growth to degeneration. Often the emphasis is on the negative impact of calcium dysregulation and the typical worse-case-scenario leading inevitably to cell death. However, even high amplitude calcium transients, when executed acutely can …

Neuropathological And Genetic Correlates Of Survival And Dementia Onset In Synucleinopathies: A Retrospective Analysis, David J. Irwin, Murray Grossman, Daniel Weintraub, Howard I. Hurtig, John E. Duda, Sharon X. Xie, Edward B. Lee, Vivianna M. Van Deerlin, Oscar L. Lopez, Julia K. Kofler, Peter T. Nelson, Gregory A. Jicha, Randy Woltjer, Joseph F. Quinn, Jeffery Kaye, James B. Leverenz, Debby Tsuang, Katelan Longfellow, Dora Yearout, Walter Kukull, C. Dirk Keene, Thomas J. Montine, Cyrus P. Zabetian, John Q. Trojanowski

Sanders-Brown Center on Aging Faculty Publications

Background

Great heterogeneity exists in survival and the interval between onset of motor symptoms and dementia symptoms across synucleinopathies. We aimed to identify genetic and pathological markers that have the strongest association with these features of clinical heterogeneity in synucleinopathies.

Methods

In this retrospective study, we examined symptom onset, and genetic and neuropathological data from a cohort of patients with Lewy body disorders with autopsy-confirmed α synucleinopathy (as of Oct 1, 2015) who were previously included in other studies from five academic institutions in five cities in the USA. We used histopathology techniques and markers to assess the burden of …

Aβ Vaccination In Combination With Behavioral Enrichment In Aged Beagles: Effects On Cognition, Aβ, And Microhemorrhages, Paulina R. Davis, Ginevra Giannini, Karin Rudolph, Nathaniel Calloway, Christopher M. Royer, Tina L. Beckett, M. Paul Murphy, Frederick Bresch, Dieter Pagani, Thomas Platt, Xiaohong Wang, Amy Skinner Donovan, Tiffany L. Sudduth, Wenjie Lou, Erin L. Abner, Richard J. Kryscio, Donna M. Wilcock, Edward G. Barrett, Elizabeth Head

Sanders-Brown Center on Aging Faculty Publications

Beta-amyloid (Aβ) immunotherapy is a promising intervention to slow Alzheimer’s disease (AD). Aging dogs naturally accumulate Aβ and show cognitive decline. An active vaccine against fibrillar Aβ 1–42 (VAC) in aged beagles resulted in maintenance but not improvement of cognition along with reduced brain Aβ. Behavioral enrichment (ENR) led to cognitive benefits but no reduction in Aβ. We hypothesized cognitive outcomes could be improved by combining VAC with ENR in aged dogs. Aged dogs (11–12 years) were placed into 4 groups: (1) control/control (C/C); (2) control/VAC (C/V); (3) ENR/control (E/C); (4) ENR and VAC (E/V) and treated for 20 months. …

Widespread Tau Seeding Activity At Early Braak Stages, Jennifer L. Furman, Jaime Vaquer-Alicea, Charles L. White, Nigel J. Cairns, Peter T. Nelson, Marc I. Diamond

Pathology and Laboratory Medicine Faculty Publications

Transcellular propagation of tau aggregates may underlie the progression of pathology in Alzheimer's disease (AD) and other tauopathies. Braak staging (B1, B2, B3) is based on phospho-tau accumulation within connected brain regions: entorhinal cortex (B1); hippocampus/limbic system (B2); and frontal and parietal lobes (B3). We previously developed a specific and sensitive assay that uses flow cytometry to quantify tissue seeding activity based on fluorescence resonance energy transfer (FRET) in cells that stably express tau reporter proteins. In a tauopathy mouse model, we have detected seeding activity far in advance of histopathological changes. It remains unknown whether individuals with AD also …

Self-Reported Head Injury And Risk Of Late-Life Impairment And Ad Pathology In An Ad Center Cohort, Erin L. Abner, Peter T. Nelson, Frederick A. Schmitt, Steven R. Browning, David W. Fardo, Lijie Wan, Gregory A. Jicha, Gregory E. Cooper, Charles D. Smith, Allison M. Caban-Holt, Linda J. Van Eldik, Richard J. Kryscio

Sanders-Brown Center on Aging Faculty Publications

Aims: To evaluate the relationship between self-reported head injury and cognitive impairment, dementia, mortality, and Alzheimer's disease (AD)-type pathological changes. Methods: Clinical and neuropathological data from participants enrolled in a longitudinal study of aging and cognition (n = 649) were analyzed to assess the chronic effects of self-reported head injury. Results: The effect of self-reported head injury on the clinical state depended on the age at assessment: for a 1-year increase in age, the OR for the transition to clinical mild cognitive impairment (MCI) at the next visit for participants with a history of head injury was 1.21 and 1.34 …

Immunotherapy In Combination With Behavioral Enrichment In A Canine Model Of Aging, Paulina R. Davis

Theses and Dissertations--Pharmacology and Nutritional Sciences

Alzheimer’s disease (AD) is characterized by cognitive decline and hallmark neuropathology, including β-amyloid (Aβ). Therapeutic strategies for AD are focusing on reducing Aβ. Canines develop Aβ neuropathology and cognitive decline with age similar to AD patients. In previous studies, immunization with Aβ1-42 (VAC) in aged canines decreased brain Aβ but did not improve cognition. Behavioral enrichment (ENR) improved cognition without reducing brain Aβ. We hypothesized that VAC combined with ENR would provide cognitive benefits and reduce Aβ neuropathology, as compared individual VAC and ENR treatments. Aged beagles were placed into groups: control, VAC with fibrillar Aβ1-42, ENR, and combination treatment …

Early Stage Drug Treatment That Normalizes Proinflammatory Cytokine Production Attenuates Synaptic Dysfunction In A Mouse Model That Exhibits Age-Dependent Progression Of Alzheimer's Disease-Related Pathology, Adam D. Bachstetter, Christopher M. Norris, Pradoldej Sompol, Donna M. Wilcock, Danielle Goulding, Janna H. Neltner, Daret St. Clair, D. Martin Watterson, Linda J. Van Eldik

Sanders-Brown Center on Aging Faculty Publications

Overproduction of proinflammatory cytokines in the CNS has been implicated as a key contributor to pathophysiology progression in Alzheimer's disease (AD), and extensive studies with animal models have shown that selective suppression of excessive glial proinflammatory cytokines can improve neurologic outcomes. The prior art, therefore, raises the logical postulation that intervention with drugs targeting dysregulated glial proinflammatory cytokine production might be effective disease-modifying therapeutics if used in the appropriate biological time window. To test the hypothesis that early stage intervention with such drugs might be therapeutically beneficial, we examined the impact of intervention with MW01-2-151SRM (MW-151), an experimental therapeutic that …