Social and Behavioral Sciences Commons^™

Sugihara Causality Analysis Of Scalp Eeg For Detection Of Early Alzheimer's Disease, Joseph C. Mcbride, Xiaopeng Zhao, Nancy B. Munro, Greg A. Jicha, Frederick A. Schmitt, Richard J. Kryscio, Charles D. Smith, Yang Jiang

Sanders-Brown Center on Aging Faculty Publications

Recently, Sugihara proposed an innovative causality concept, which, in contrast to statistical predictability in Granger sense, characterizes underlying deterministic causation of the system. This work exploits Sugihara causality analysis to develop novel EEG biomarkers for discriminating normal aging from mild cognitive impairment (MCI) and early Alzheimer's disease (AD). The hypothesis of this work is that scalp EEG based causality measurements have different distributions for different cognitive groups and hence the causality measurements can be used to distinguish between NC, MCI, and AD participants. The current results are based on 30-channel resting EEG records from 48 age-matched participants (mean age 75.7 …

Alzheimer's Therapeutics Targeting Amyloid Beta 1–42 Oligomers Ii: Sigma-2/Pgrmc1 Receptors Mediate Abeta 42 Oligomer Binding And Synaptotoxicity, Nicholas J. Izzo, Jinbin Xu, Chenbo Zeng, Molly J. Kirk, Kelsie Mozzoni, Colleen Silky, Courtney Rehak, Raymond Yurko, Gary Look, Gilbert Rishton, Hank Safferstein, Carlos Cruchaga, Alison Goate, Michael A. Cahill, Ottavio Arancio, Robert H. Mach, Rolf Craven, Elizabeth Head, Harry Levine Iii, Tara L. Spires-Jones, Susan M. Catalano

Sanders-Brown Center on Aging Faculty Publications

Amyloid beta (Abeta) 1-42 oligomers accumulate in brains of patients with Mild Cognitive Impairment (MCI) and disrupt synaptic plasticity processes that underlie memory formation. Synaptic binding of Abeta oligomers to several putative receptor proteins is reported to inhibit long-term potentiation, affect membrane trafficking and induce reversible spine loss in neurons, leading to impaired cognitive performance and ultimately to anterograde amnesia in the early stages of Alzheimer's disease (AD). We have identified a receptor not previously associated with AD that mediates the binding of Abeta oligomers to neurons, and describe novel therapeutic antagonists of this receptor capable of blocking Abeta toxic …

Alzheimer's Therapeutics Targeting Amyloid Beta 1-42 Oligomers I: Abeta 42 Oligomer Binding To Specific Neuronal Receptors Is Displaced By Drug Candidates That Improve Cognitive Deficits, Nicholas J. Izzo, Agnes Staniszewski, Lillian To, Mauro Fa, Andrew F. Teich, Faisal Saeed, Harrison Wostein, Thomas Walko Iii, Anisha Vaswani, Meghan Wardius, Zanobia Syed, Jessica Ravenscroft, Kelsie Mozzoni, Colleen Silky, Courtney Rehak, Raymond Yurko, Patricia Finn, Gary Look, Gilbert Rishton, Hank Safferstein, Miles Miller, Conrad Johanson, Edward Stopa, Manfred Windisch, Birgit Hutter-Paier, Mehrdad Shamloo, Ottavio Arancio, Harry Levine Iii, Susan M. Catalano

Sanders-Brown Center on Aging Faculty Publications

Synaptic dysfunction and loss caused by age-dependent accumulation of synaptotoxic beta amyloid (Abeta) 1-42 oligomers is proposed to underlie cognitive decline in Alzheimer's disease (AD). Alterations in membrane trafficking induced by Abeta oligomers mediates reduction in neuronal surface receptor expression that is the basis for inhibition of electrophysiological measures of synaptic plasticity and thus learning and memory. We have utilized phenotypic screens in mature, in vitro cultures of rat brain cells to identify small molecules which block or prevent the binding and effects of Abeta oligomers. Synthetic Abeta oligomers bind saturably to a single site on neuronal synapses and induce …

The P38alpha Mitogen-Activated Protein Kinase Limits The Cns Proinflammatory Cytokine Response To Systemic Lipopolysaccharide, Potentially Through An Il-10 Dependent Mechanism, Adam D. Bachstetter, Bin Xing, Linda J. Van Eldik

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: The p38α mitogen-activated protein kinase (MAPK) is a well-characterized intracellular kinase involved in the overproduction of proinflammatory cytokines from glia. As such, p38α appears to be a promising therapeutic target for neurodegenerative diseases associated with neuroinflammation. However, the in vivo role of p38α in cytokine production in the CNS is poorly defined, and prior work suggests that p38α may be affecting a yet to be identified negative feedback mechanism that limits the acute, injury-induced proinflammatory cytokine surge in the CNS.

METHODS: To attempt to define this negative feedback mechanism, we used two in vitro and two in vivo models …

Self-Reported Memory Complaints: Implications From A Longitudinal Cohort With Autopsies, Richard J. Kryscio, Erin L. Abner, Gregory E. Cooper, David W. Fardo, Greg A. Jicha, Peter T. Nelson, Charles D. Smith, Linda J. Van Eldik, Lijie Wan, Frederick A. Schmitt

Sanders-Brown Center on Aging Faculty Publications

OBJECTIVE: We assessed salience of subjective memory complaints (SMCs) by older individuals as a predictor of subsequent cognitive impairment while accounting for risk factors and eventual neuropathologies.

METHODS: Subjects (n = 531) enrolled while cognitively intact at the University of Kentucky were asked annually if they perceived changes in memory since their last visit. A multistate model estimated when transition to impairment occurred while adjusting for intervening death. Risk factors affecting the timing and probability of an impairment were identified. The association between SMCs and Alzheimer-type neuropathology was assessed from autopsies (n = 243).

RESULTS: SMCs were …

Con: Are We Ready To Translate Alzheimer's Disease-Modifying Therapies To People With Down Syndrome?, Elizabeth Head, Frederick A. Schmitt

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Adults with Down syndrome develop Alzheimer's disease neuropathology in an age-dependent manner. This unique feature provides an opportunity to test interventions targeted for prevention of Alzheimer's disease neuropathology and dementia in Down syndrome.

DISCUSSION: In considering clinical trial designs, however, there are several challenges that we believe will be critical to examine further. These include: accuracy in dementia, mild cognitive impairment and preclinical Alzheimer's disease diagnoses in Down syndrome; clinical trial outcome measures appropriate for individuals with Down syndrome; in vivo imaging outcome measures (and practical considerations); and contributions of medical co-morbidities to disease progression. Also, when studies are …

Calcineurin And Glial Signaling: Neuroinflammation And Beyond, Jennifer L. Furman, Christopher M. Norris

Sanders-Brown Center on Aging Faculty Publications

Similar to peripheral immune/inflammatory cells, neuroglial cells appear to rely on calcineurin (CN) signaling pathways to regulate cytokine production and cellular activation. Several studies suggest that harmful immune/inflammatory responses may be the most impactful consequence of aberrant CN activity in glial cells. However, newly identified roles for CN in glutamate uptake, gap junction regulation, Ca²⁺ dyshomeostasis, and amyloid production suggest that CN's influence in glia may extend well beyond neuroinflammation. The following review will discuss the various actions of CN in glial cells, with particular emphasis on astrocytes, and consider the implications for neurologic dysfunction arising with aging, injury, …

Transition From An M1 To A Mixed Neuroinflammatory Phenotype Increases Amyloid Deposition In App/Ps1 Transgenic Mice, Erica M. Weekman, Tiffany L. Sudduth, Erin L. Abner, Gabriel J. Popa, Michael D. Mendenhall, Holly M. Brothers, Kaitlyn Braun, Abigail Greenstein, Donna M. Wilcock

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: The polarization to different neuroinflammatory phenotypes has been described in early Alzheimer's disease, yet the impact of these phenotypes on amyloid-beta (Aβ) pathology remains unknown. Short-term studies show that induction of an M1 neuroinflammatory phenotype reduces Aβ, but long-term studies have not been performed that track the neuroinflammatory phenotype.

METHODS: Wild-type and APP/PS1 transgenic mice aged 3 to 4 months received a bilateral intracranial injection of adeno-associated viral (AAV) vectors expressing IFNγ or green fluorescent protein in the frontal cortex and hippocampus. Mice were sacrificed 4 or 6 months post-injection. ELISA measurements were used for IFNγ protein levels and …

Obesity And Diabetes Cause Cognitive Dysfunction In The Absence Of Accelerated Β-Amyloid Deposition In A Novel Murine Model Of Mixed Or Vascular Dementia, Dana M. Niedowicz, Valerie L. Reeves, Thomas L. Platt, Katharina Kohler, Tina L. Beckett, David K. Powell, Tiffany L. Lee, Travis R. Sexton, Eun Suk Song, Lawrence D. Brewer, Caitlin S. Latimer, Susan D. Kraner, Kara L. Larson, Sabire Özcan, Christopher M. Norris, Louis B. Hersh, Nada M. Porter, Donna M. Wilcock, Michael Paul Murphy

Sanders-Brown Center on Aging Faculty Publications

Mid-life obesity and type 2 diabetes mellitus (T2DM) confer a modest, increased risk for Alzheimer's disease (AD), though the underlying mechanisms are unknown. We have created a novel mouse model that recapitulates features of T2DM and AD by crossing morbidly obese and diabetic db/db mice with APP^ΔNL/ΔNLx PS1^P264L/P264L knock-in mice. These mice (db/AD) retain many features of the parental lines (e.g. extreme obesity, diabetes, and parenchymal deposition of β-amyloid (Aβ)). The combination of the two diseases led to additional pathologies-perhaps most striking of which was the presence of severe cerebrovascular pathology, including aneurysms and small …

Genetics Of Picalm Expression And Alzheimer's Disease, Ishita Parikh, David W. Fardo, Steven Estus

Sanders-Brown Center on Aging Faculty Publications

Novel Alzheimer's disease (AD) risk factors have been identified by genome-wide association studies. Elucidating the mechanism underlying these factors is critical to the validation process and, by identifying rate-limiting steps in AD risk, may yield novel therapeutic targets. Here, we evaluated the association between the AD-associated polymorphism rs3851179 near PICALM, which encodes a clathrin-coated pit accessory protein. Immunostaining established that PICALM is expressed predominately in microvessels in human brain. Consistent with this finding, PICALM mRNA expression correlated with expression of the endothelial genes vWF and CD31. Additionally, we found that PICALM expression was modestly increased with the rs3851179A …

Soluble Apoe/Aβ Complex: Mechanism And Therapeutic Target For Apoe4-Induced Ad Risk, Leon M. Tai, Shipra Mehra, Varsha Shete, Steven Estus, G. William Rebeck, Guojun Bu, Mary Jo Ladu

Sanders-Brown Center on Aging Faculty Publications

The APOE4 allele of apolipoprotein E (apoE) is the greatest genetic risk factor for Alzheimer's disease (AD) compared to APOE2 and APOE3. Amyloid-β (Aβ), particularly in a soluble oligomeric form (oAβ), is considered a proximal cause of neurodegeneration in AD. Emerging data indicate that levels of soluble oAβ are increased with APOE4, providing a potential mechanism of APOE4-induced AD risk. However, the pathway(s) by which apoE4 may increase oAβ levels are unclear and the subject of continued inquiry. In this editorial review, we present the hypothesis that apoE isoform-specific interactions with Aβ, namely apoE/Aβ complex, modulate Aβ levels. Specifically, we …

Let’S Play: Understanding The Role And Significance Of Digital Gaming In Old Age, Julie A. Skalsky Brown

Theses and Dissertations--Gerontology

Despite a marked increase in the use of digital games among older persons, there is insufficient research that provides insight into the gaming experiences of this population. A major demographic shift within the senior gaming market has ushered in a new perspective on the use of digital games as a tool for physical and cognitive health, and improved socialization. It is proposed that individual notions of play, which are developed over the life course, influence digital game play engagement and interaction preferences, and contribute to well-being. This study explored how self-perceptions of play over the course of the senior gamer’s …