Life Sciences Commons^™

A Customized Quantitative Pcr Microrna Panel Provides A Technically Robust Context For Studying Neurodegenerative Disease Biomarkers And Indicates A High Correlation Between Cerebrospinal Fluid And Choroid Plexus Microrna Expression, Wang-Xia Wang, David W. Fardo, Gregory A. Jicha, Peter T. Nelson

Sanders-Brown Center on Aging Faculty Publications

MicroRNA (miRNA) expression varies in association with different tissue types and in diseases. Having been found in body fluids including blood and cerebrospinal fluid (CSF), miRNAs constitute potential biomarkers. CSF miRNAs have been proposed as biomarkers for neurodegenerative diseases; however, there is a lack of consensus about the best candidate miRNA biomarkers and there has been variability in results from different research centers, perhaps due to technical factors. Here, we sought to optimize technical parameters for CSF miRNA studies. We examined different RNA isolation methods and performed miRNA expression profiling with TaqMan® miRNA Arrays. More specifically, we developed a customized …

Brain Energy Homeostasis And The Regulation Of N-Acetyl-Aspartate Metabolism In Development And Disease, Samantha Zaroff

Graduate School of Biomedical Sciences Theses and Dissertations

N-acetylaspartate (NAA) is a non-invasive clinical marker of neuronal metabolic integrity because of its strong proton magnetic resonance spectroscopy (H-MRS) peak and direct correlation with energetic integrity. Specifically, NAA is used to track the progression of neurodegenerative diseases due to the characteristic reduction of whole brain levels of NAA which occur simultaneously with reduced glucose utilization and mitochondrial dysfunction, but prior to the onset of disease specific pathology. However, NAA will also significantly increase simultaneously with energetic integrity during periods of recovery or remission in applicable disorders, such as traumatic brain injuries. Unfortunately, it remains enigmatic exactly why NAA is …

Linkage, Whole Genome Sequence, And Biological Data Implicate Variants In Rab10 In Alzheimer's Disease Resilience., Perry G Ridge, Celeste M Karch, Simon Hsu, Ivan Arano, Craig C Teerlink, Mark T W Ebbert, Josue D Gonzalez Murcia, James M Farnham, Anna R Damato, Mariet Allen, Xue Wang, Oscar Harari, Victoria M Fernandez, Rita Guerreiro, Jose Bras, John Hardy, Ronald Munger, Maria Norton, Celeste Sassi, Andrew Singleton, Steven G Younkin, Dennis W Dickson, Todd E Golde, Nathan D Price, Nilüfer Ertekin-Taner, Carlos Cruchaga, Alison M Goate, Christopher Corcoran, Joann Tschanz, Lisa A Cannon-Albright, John S K Kauwe

Articles, Abstracts, and Reports

BACKGROUND: While age and the APOE ε4 allele are major risk factors for Alzheimer's disease (AD), a small percentage of individuals with these risk factors exhibit AD resilience by living well beyond 75 years of age without any clinical symptoms of cognitive decline.

METHODS: We used over 200 "AD resilient" individuals and an innovative, pedigree-based approach to identify genetic variants that segregate with AD resilience. First, we performed linkage analyses in pedigrees with resilient individuals and a statistical excess of AD deaths. Second, we used whole genome sequences to identify candidate SNPs in significant linkage regions. Third, we replicated SNPs …

Low Arousal Positive Emotional Stimuli Attenuate Aberrant Working Memory Processing In Persons With Mild Cognitive Impairment, Lucas S. Broster, Shonna L. Jenkins, Sarah D. Holmes, Gregory A. Jicha, Yang Jiang

Behavioral Science Faculty Publications

Emotional enhancement effects on memory have been reported to mitigate the pathophysiology of Alzheimer’s disease (AD). However, relative to their manifestation in persons without pathologic aging, these effects may be reduced in magnitude or even deleterious, especially in tasks that more closely model ecologic memory performance. Based upon a synthesis of such reports, we hypothesized that in persons with AD low arousal positive stimuli would evoke relatively intact emotional enhancement effects, but that high arousal negative stimuli would evoke disordered emotional enhancement effects. To assess this, participants with and without mild cognitive impairment (MCI) presumed to be due to AD …

Chronic Traumatic Encephalopathy-Integration Of Canonical Traumatic Brain Injury Secondary Injury Mechanisms With Tau Pathology, Jacqueline R. Kulbe, Edward D. Hall

Spinal Cord and Brain Injury Research Center Faculty Publications

In recent years, a new neurodegenerative tauopathy labeled Chronic Traumatic Encephalopathy (CTE), has been identified that is believed to be primarily a sequela of repeated mild traumatic brain injury (TBI), often referred to as concussion, that occurs in athletes participating in contact sports (e.g. boxing, football, football, rugby, soccer, ice hockey) or in military combatants, especially after blast-induced injuries. Since the identification of CTE, and its neuropathological finding of deposits of hyperphosphorylated tau protein, mechanistic attention has been on lumping the disorder together with various other non-traumatic neurodegenerative tauopathies. Indeed, brains from suspected CTE cases that have come to autopsy …

Targeting Mitochondrial Dysfunction In Cns Injury Using Methylene Blue; Still A Magic Bullet?, Hemendra J. Vekaria, Lora Talley Watts, Ai-Ling Lin, Patrick G. Sullivan

Spinal Cord and Brain Injury Research Center Faculty Publications

Complex, multi-factorial secondary injury cascades are initiated following traumatic brain injury, which makes this a difficult disease to treat. The secondary injury cascades following the primary mechanical tissue damage, are likely where effective therapeutic interventions may be targeted. One promising therapeutic target following brain injury are mitochondria. Mitochondria are complex organelles found within the cell, which act as powerhouses within all cells by supplying ATP. These organelles are also necessary for calcium cycling, redox signaling and play a major role in the initiation of cell death pathways. When mitochondria become dysfunctional, there is a tendency for the cell to loose …

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 …

Impulsive Personality Dimensions Are Associated With Altered Behavioral Performance And Neural Responses In The Monetary Incentive Delay Task, Ruolei Gu, Yang Jiang, Seth Kiser, Chelsea L. Black, Lucas S. Broster, Yue-Jia Luo, Thomas H. Kelly

Behavioral Science Faculty Publications

Individual differences in dimensions of impulsivity personality including disinhibition and sensation seeking modulate approach responses to reinforcing stimuli, such as drugs and money. The current study examined the effects of monetary incentive on both behavioral performance and electrophysiological activity among individuals varying in disinhibition and sensation seeking. The monetary incentive delay (MID) task was completed under electroencephalogram (EEG) recording. Behavioral data showed that higher disinhibition and sensation-seeking were associated with lower performance accuracy. Event-related potential (ERP) data showed that high reinforcement cues elicited a larger late positive component (LPC) than other conditions among high disinhibition participants, indicating its strong emotional …

Alzheimer's Disease Genetics And Abca7 Splicing, Jared B. Vasquez, James F. Simpson, Ryan Harpole, Steven Estus

Physiology Faculty Publications

Both common and rare polymorphisms within ABCA7 have been associated with Alzheimer’s disease (AD). In particular, the rare AD associated polymorphism rs200538373 was associated with altered ABCA7 exon 41 splicing and an AD risk odds ratio of ∼1.9. To probe the role of this polymorphism in ABCA7 splicing, we used minigene studies and qPCR of human brain RNA. We report aberrant ABCA7 exon 41 splicing in the brain of a carrier of the rs200538373 minor C allele. Moreover, minigene studies show that rs200538373 acts as a robust functional variant in vitro. Lastly, although the ABCA7 isoform with an extended …

Sex Differences In The Drinking Response To Angiotensin Ii (Angii): Effect Of Body Weight, Jessica Santollo, Ann-Marie Torregrossa, Derek Daniels

Biology Faculty Publications

Sex differences in fluid intake stimulated by angiotensin II (AngII) have been reported, but the direction of the differences is inconsistent. To resolve these discrepancies, we measured water intake by male and female rats given AngII. Males drank more than females, but when intake was normalized to body weight, the sex difference was reversed. Weight-matched males and females, however, had no difference in intake. Using a linear mixed model analysis, we found that intake was influenced by weight, sex, and AngII dose. We used linear regression to disentangle these effects further. Comparison of regression coefficients revealed sex and weight differences …

Nfatc2 Modulates Microglial Activation In The Aβpp/Ps1 Mouse Model Of Alzheimer's Disease, Gunjan D. Manocha, Atreyi Ghatak, Kendra L. Puig, Susan D. Kraner, Christopher M. Norris, Colin K. Combs

Pharmacology and Nutritional Sciences Faculty Publications

Alzheimer’s disease (AD) brains are characterized by fibrillar amyloid-β (Aβ) peptide containing plaques and associated reactive microglia. The proinflammatory phenotype of the microglia suggests that they may negatively affect disease course and contribute to behavioral decline. This hypothesis predicts that attenuating microglial activation may provide benefit against disease. Prior work from our laboratory and others has characterized a role for the transcription factor, nuclear factor of activated T cells (NFAT), in regulating microglial phenotype in response to different stimuli, including Aβ peptide. We observed that the NFATc2 isoform was the most highly expressed in murine microglia cultures, and inhibition or …

Transcranial Direct Current Stimulation And Sports Performance, Dylan J. Edwards, Mar Cortes, Susan Wortman-Jutt, David Putrino, Marom Bikson, Gary Thickbroom, Alvaro Pascual-Leone

Publications and Research

No abstract provided.

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 …

Translational Models For Vascular Cognitive Impairment: A Review Including Larger Species, Atticus H. Hainsworth, Stuart M. Allan, Johannes Boltze, Catriona Cunningham, Chad Farris, Elizabeth Head, Masafumi Ihara, Jeremy D. Isaacs, Raj N. Kalaria, Saskia A. M. J. Lesnik Oberstein, Mark B. Moss, Björn Nitzsche, Gary A. Rosenberg, Julie W. Rutten, Melita Salkovic-Petrisic, Aron M. Troen

Pharmacology and Nutritional Sciences Faculty Publications

Background: Disease models are useful for prospective studies of pathology, identification of molecular and cellular mechanisms, pre-clinical testing of interventions, and validation of clinical biomarkers. Here, we review animal models relevant to vascular cognitive impairment (VCI). A synopsis of each model was initially presented by expert practitioners. Synopses were refined by the authors, and subsequently by the scientific committee of a recent conference (International Conference on Vascular Dementia 2015). Only peer-reviewed sources were cited.

Methods: We included models that mimic VCI-related brain lesions (white matter hypoperfusion injury, focal ischaemia, cerebral amyloid angiopathy) or reproduce VCI risk factors (old age, hypertension, …

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. …

Steroidogenesis In The Green Anole Lizard Brain And Gonad, Christine Peek

All Graduate Theses, Dissertations, and Other Capstone Projects

Seasonally breeding animals reproduce during certain times of the year and, subsequently, behaviors, steroid hormone levels, and brain morphology change. The green anole lizard (Anolis carolinensis) is an excellent model to study the regulation of steroid hormone production because they have distinct hormonal and behavioral differences between sexes and seasons. As in other vertebrates, steroidogenesis in anoles is under the control of the hypothalamus-pituitary-gonadal (HPG) axis. We tested the hypothesis that natural variations in steroid hormone levels between sexes and seasons are mediated within the brain and gonad by examining four genes involved in steroidogenesis: StAR, Cyp17α1, HSD17β3, and Cyp19α1. …

Peripheral Huntingtin Silencing Does Not Ameliorate Central Signs Of Disease In The B6.Httq111/+ Mouse Model Of Huntington's Disease., Sydney R Coffey, Robert M Bragg, Shawn Minnig, Seth A Ament, Jeffrey P Cantle, Anne Glickenhaus, Daniel Shelnut, José M Carrillo, Dominic D Shuttleworth, Julie-Anne Rodier, Kimihiro Noguchi, C Frank Bennett, Nathan D Price, Holly B Kordasiewicz, Jeffrey B Carroll

Articles, Abstracts, and Reports

Huntington's disease (HD) is an autosomal dominant neurodegenerative disease whose predominant neuropathological signature is the selective loss of medium spiny neurons in the striatum. Despite this selective neuropathology, the mutant protein (huntingtin) is found in virtually every cell so far studied, and, consequently, phenotypes are observed in a wide range of organ systems both inside and outside the central nervous system. We, and others, have suggested that peripheral dysfunction could contribute to the rate of progression of striatal phenotypes of HD. To test this hypothesis, we lowered levels of huntingtin by treating mice with antisense oligonucleotides (ASOs) targeting the murine …

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 …