Geriatrics Commons^™

Discrimination Of Mild Cognitive Impairment And Alzheimer's Disease Using Transfer Entropy Measures Of Scalp Eeg, Joseph Mcbride, Xiaopeng Zhao, Nancy Munro, Gregory Jicha, Charles Smith, Yang Jiang

Sanders-Brown Center on Aging Faculty Publications

Mild cognitive impairment (MCI) is a neurological condition related to early stages of dementia including Alzheimer's disease (AD). This study investigates the potential of measures of transfer entropy in scalp EEG for effectively discriminating between normal aging, MCI, and AD participants. Resting EEG records from 48 age-matched participants (mean age 75.7 years)-15 normal controls, 16 MCI, and 17 early AD-are examined. The mean temporal delays corresponding to peaks in inter-regional transfer entropy are computed and used as features to discriminate between the three groups of participants. Three-way classification schemes based on binary support vector machine models demonstrate overall discrimination accuracies …

Reassessment Of Risk Genotypes (Grn, Tmem106b, And Abcc9 Variants) Associated With Hippocampal Sclerosis Of Aging Pathology, Peter T. Nelson, Wang-Xia Wang, Amanda B. Partch, Sarah E. Monsell, Otto Valladares, Sally R. Ellingson, Bernard R. Wilfred, Adam C. Naj, Li-San Wang, Walter A. Kukull, David W. Fardo

Pathology and Laboratory Medicine Faculty Publications

Hippocampal sclerosis of aging (HS-Aging) is a common high-morbidity neurodegenerative condition in elderly persons. To understand the risk factors for HS-Aging, we analyzed data from the Alzheimer’s Disease Genetics Consortium and correlated the data with clinical and pathologic information from the National Alzheimer’s Coordinating Center database. Overall, 268 research volunteers with HS-Aging and 2,957 controls were included; detailed neuropathologic data were available for all. The study focused on single-nucleotide polymorphisms previously associated with HS-Aging risk: rs5848 ( GRN ), rs1990622 ( TMEM106B ), and rs704180 ( ABCC9 ). Analyses of a subsample that was not previously evaluated (51 HS-Aging cases …

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 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 …

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 …

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 …

A Study Of Small Rnas From Cerebral Neocortex Of Pathology-Verified Alzheimer's Disease, Dementia With Lewy Bodies, Hippocampal Sclerosis, Frontotemporal Lobar Dementia, And Non-Demented Human Controls, Sébastien S. Hébert, Wang-Xia Wang, Qi Zhu, Peter T. Nelson

Sanders-Brown Center on Aging Faculty Publications

MicroRNAs (miRNAs) are small (20-22 nucleotides) regulatory non-coding RNAs that strongly influence gene expression. Most prior studies addressing the role of miRNAs in neurodegenerative diseases (NDs) have focused on individual diseases such as Alzheimer's disease (AD), making disease-to-disease comparisons impossible. Using RNA deep sequencing, we sought to analyze in detail the small RNAs (including miRNAs) in the temporal neocortex gray matter from non-demented controls (n = 2), AD (n = 5), dementia with Lewy bodies (n = 4), hippocampal sclerosis of aging (n = 4), and frontotemporal lobar dementia (FTLD) (n = 5) cases, together accounting for the most prevalent …

Practice Effects In A Longitudinal, Multi-Center Alzheimer's Disease Prevention Clinical Trial, Erin L. Abner, Brandon C. Dennis, Melissa J. Mathews, Marta S. Mendiondo, Allison Caban-Holt, Richard J. Kryscio, Frederick A. Schmitt, John J. Crowley

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Practice effects are a known threat to reliability and validity in clinical trials. Few studies have investigated the potential influence of practice on repeated screening measures in longitudinal clinical trials with a focus on dementia prevention. The current study investigates whether practice effects exist on a screening measure commonly used in aging research, the Memory Impairment Screen (MIS).

METHODS: The PREADViSE trial is a clinical intervention study evaluating the efficacy of vitamin E and selenium for Alzheimer's disease prevention. Participants are screened annually for incident dementia with the MIS. Participants with baseline and three consecutive follow-ups who made less …

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 …

Genetics Of Clusterin Isoform Expression And Alzheimer's Disease Risk, I-Fang Ling, Jiraganya Bhongsatiern, James F. Simpson, David W. Fardo, Steven Estus

Sanders-Brown Center on Aging Faculty Publications

The minor allele of rs11136000 within CLU is strongly associated with reduced Alzheimer's disease (AD) risk. The mechanism underlying this association is unclear. Here, we report that CLU1 and CLU2 are the two primary CLU isoforms in human brain; CLU1 and CLU2 share exons 2-9 but differ in exon 1 and proximal promoters. The expression of both CLU1 and CLU2 was increased in individuals with significant AD neuropathology. However, only CLU1 was associated with the rs11136000 genotype, with the minor "protective" rs11136000T allele being associated with increased CLU1 expression. Since CLU1 and CLU2 are predicted to encode intracellular and secreted …

Lithium Treatment Of Appswdi/Nos2−/− Mice Leads To Reduced Hyperphosphorylated Tau, Increased Amyloid Deposition And Altered Inflammatory Phenotype, Tiffany L. Sudduth, Joan G. Wilson, Angela Everhart, Carol A. Colton, Donna M. Wilcock

Sanders-Brown Center on Aging Faculty Publications

Lithium is an anti-psychotic that has been shown to prevent the hyperphosphorylation of tau protein through the inhibition of glycogen-synthase kinase 3-beta (GSK3β). We recently developed a mouse model that progresses from amyloid pathology to tau pathology and neurodegeneration due to the genetic deletion of NOS2 in an APP transgenic mouse; the APPSwDI/NOS2-/- mouse. Because this mouse develops tau pathology, amyloid pathology and neuronal loss we were interested in the effect anti-tau therapy would have on amyloid pathology, learning and memory. We administered lithium in the diets of APPSwDI/NOS2-/- mice for a period of eight months, followed by water maze …

Conformational Altered P53 As An Early Marker Of Oxidative Stress In Alzheimer's Disease, Laura Buizza, Giovanna Cenini, Cristina Lanni, Giulia Ferrari-Toninelli, Chiara Prandelli, Stefano Govoni, Erica Buoso, Marco Racchi, Maria Barcikowska, Maria Styczynska, Aleksandra Szybinska, D. Allan Butterfield, Maurizio Memo, Daniela Uberti

Sanders-Brown Center on Aging Faculty Publications

In order to study oxidative stress in peripheral cells of Alzheimer's disease (AD) patients, immortalized lymphocytes derived from two peculiar cohorts of patients, referring to early onset AD (EOSAD) and subjects harboured AD related mutation (ADmut), were used. Oxidative stress was evaluated measuring i) the typical oxidative markers, such as HNE Michel adducts, 3 Nitro-Tyrosine residues and protein carbonyl on protein extracts, ii) and the antioxidant capacity, following the enzymatic kinetic of superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GRD). We found that the signs of oxidative stress, measured as oxidative marker levels, were evident only in ADmut …

Neuroangiogenesis: A Vascular Basis For Alzheimer's Disease And Cognitive Decline During Aging, Charles T. Ambrose

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Angiogenesis directs development of the brain's microcirculation during antenatal and postnatal development, but its role later in life is less well recognized. I contend that during senescence a reduced cerebral capillary density accounts in part for the vascular cognitive impairment observed in many older persons and possibly for some forms of Alzheimer's disease. I propose that neuroangiogenesis is essential throughout adult life for maintaining the microcirculation of the cerebral cortex and elsewhere in the brain and that it commonly declines with old age. To support this hypothesis I have examined the neurological literature for relevant studies on cerebral capillary density …

Elevated Stearoyl-Coa Desaturase In Brains Of Patients With Alzheimer's Disease, Giuseppe Astarita, Kwang-Mook Jung, Vitaly Vasilevko, Nicholas V. Dipatrizio, Sarah K. Martin, David H. Cribbs, Elizabeth Head, Carl W. Cotman, Daniele Piomelli

Sanders-Brown Center on Aging Faculty Publications

The molecular bases of Alzheimer's disease (AD) remain unclear. We used a lipidomic approach to identify lipid abnormalities in the brains of subjects with AD (N = 37) compared to age-matched controls (N = 17). The analyses revealed statistically detectable elevations in levels of non-esterified monounsaturated fatty acids (MUFAs) and mead acid (20:3n-9) in mid-frontal cortex, temporal cortex and hippocampus of AD patients. Further studies showed that brain mRNAs encoding for isoforms of the rate-limiting enzyme in MUFAs biosynthesis, stearoyl-CoA desaturase (SCD-1, SCD-5a and SCD-5b), were elevated in subjects with AD. The monounsaturated/saturated fatty acid ratio ('desaturation index')--displayed a strong …

Rna Oxidation Adducts 8-Ohg And 8-Oha Change With Aβ42 Levels In Late-Stage Alzheimer's Disease, Adam M. Weidner, Melissa A. Bradley, Tina L. Beckett, Dana M. Niedowicz, Amy L.S. Dowling, Sergey V. Matveev, Harry Levine, Mark A. Lovell, M. Paul Murphy

Sanders-Brown Center on Aging Faculty Publications

While research supports amyloid-β (Aβ) as the etiologic agent of Alzheimer's disease (AD), the mechanism of action remains unclear. Evidence indicates that adducts of RNA caused by oxidation also represent an early phenomenon in AD. It is currently unknown what type of influence these two observations have on each other, if any. We quantified five RNA adducts by gas chromatography/mass spectroscopy across five brain regions from AD cases and age-matched controls. We then used a reductive directed analysis to compare the RNA adducts to common indices of AD neuropathology and various pools of Aβ. Using data from four disease-affected brain …

Activation Of Matrix Metalloproteinases Following Anti-Aβ Immunotherapy; Implications For Microhemorrhage Occurrence, Donna M. Wilcock, Dave Morgan, Marcia N. Gordon, Tiffany L. Taylor, Lisa A. Ridnour, David A. Wink, Carol A. Colton

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Anti-Aβ immunotherapy is a promising approach to the prevention and treatment of Alzheimer's disease (AD) currently in clinical trials. There is extensive evidence, both in mice and humans that a significant adverse event is the occurrence of microhemorrhages. Also, vasogenic edema was reported in phase 2 of a passive immunization clinical trial. In order to overcome these vascular adverse effects it is critical that we understand the mechanism(s) by which they occur.

METHODS: We have examined the matrix metalloproteinase (MMP) protein degradation system in two previously published anti-Aβ immunotherapy studies. The first was a passive immunization study in which …

Epigenetic Silencing Of Nucleolar Rrna Genes In Alzheimer's Disease, Maciej Pietrzak, Grzegorz Rempala, Peter T. Nelson, Jing-Juan Zheng, Michal Hetman

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Ribosomal deficits are documented in mild cognitive impairment (MCI), which often represents an early stage Alzheimer's disease (AD), as well as in advanced AD. The nucleolar rRNA genes (rDNA), transcription of which is critical for ribosomal biogenesis, are regulated by epigenetic silencing including promoter CpG methylation.

METHODOLOGY/PRINCIPAL FINDINGS: To assess whether CpG methylation of the rDNA promoter was dysregulated across the AD spectrum, we analyzed brain samples from 10 MCI-, 23 AD-, and, 24 age-matched control individuals using bisulfite mapping. The rDNA promoter became hypermethylated in cerebro-cortical samples from MCI and AD groups. In parietal cortex, the rDNA promoter …

Patterns Of Microrna Expression In Normal And Early Alzheimer's Disease Human Temporal Cortex: White Matter Versus Gray Matter, Wang-Xia Wang, Qingwei Huang, Yanling Hu, Arnold J. Stromberg, Peter T. Nelson

Pathology and Laboratory Medicine Faculty Publications

MicroRNA (miRNA) expression was assessed in human cerebral cortical gray matter (GM) and white matter (WM) in order to provide the first insights into the difference between GM and WM miRNA repertoires across a range of Alzheimer's disease (AD) pathology. RNA was isolated separately from GM and WM portions of superior and middle temporal cerebral cortex (N = 10 elderly females, postmortem interval < 4 h). miRNA profiling experiments were performed using state-of-the-art Exiqon^© LNA-microarrays. A subset of miRNAs that appeared to be strongly expressed according to the microarrays did not appear to be conventional miRNAs according to Northern blot analyses. Some well-characterized miRNAs were substantially enriched in WM …

Deficient Liver Biosynthesis Of Docosahexaenoic Acid Correlates With Cognitive Impairment In Alzheimer's Disease, Giuseppe Astarita, Kwang-Mook Jung, Nicole C. Berchtold, Vinh Q. Nguyen, Daniel L. Gillen, Elizabeth Head, Carl W. Cotman, Daniele Piomelli

Sanders-Brown Center on Aging Faculty Publications

Reduced brain levels of docosahexaenoic acid (C22:6n-3), a neurotrophic and neuroprotective fatty acid, may contribute to cognitive decline in Alzheimer's disease. Here, we investigated whether the liver enzyme system that provides docosahexaenoic acid to the brain is dysfunctional in this disease. Docosahexaenoic acid levels were reduced in temporal cortex, mid-frontal cortex and cerebellum of subjects with Alzheimer's disease, compared to control subjects (P = 0.007). Mini Mental State Examination (MMSE) scores positively correlated with docosahexaenoic/α-linolenic ratios in temporal cortex (P = 0.005) and mid-frontal cortex (P = 0.018), but not cerebellum. Similarly, liver docosahexaenoic acid content was lower in Alzheimer's …

Molecular Cross Talk Between Misfolded Proteins In Animal Models Of Alzheimer's And Prion Diseases, Rodrigo Morales, Lisbell D Estrada, Rodrigo Diaz-Espinoza, Diego Morales-Scheihing, Maria C Jara, Joaquin Castilla, Claudio Soto

Faculty, Staff and Student Publications

The central event in protein misfolding disorders (PMDs) is the accumulation of a misfolded form of a naturally expressed protein. Despite the diversity of clinical symptoms associated with different PMDs, many similarities in their mechanism suggest that distinct pathologies may cross talk at the molecular level. The main goal of this study was to analyze the interaction of the protein misfolding processes implicated in Alzheimer's and prion diseases. For this purpose, we inoculated prions in an Alzheimer's transgenic mouse model that develop typical amyloid plaques and followed the progression of pathological changes over time. Our findings show a dramatic acceleration …

Omega-3 Fatty Acids: Potential Role In The Management Of Early Alzheimer's Disease, Gregory A. Jicha, William R. Markesbery

Sanders-Brown Center on Aging Faculty Publications

Omega-3 fatty acids are essential for brain growth and development. They play an important role throughout life, as critical modulators of neuronal function and regulation of oxidative stress mechanisms, in brain health and disease. Docosahexanoic acid (DHA), the major omega-3 fatty acid found in neurons, has taken on a central role as a target for therapeutic intervention in Alzheimer's disease (AD). A plethora of in vitro, animal model, and human data, gathered over the past decade, highlight the important role DHA may play in the development of a variety of neurological and psychiatric disorders, including AD. Cross sectional and prospective …

The Expression Of Microrna Mir-107 Decreases Early In Alzheimer's Disease And May Accelerate Disease Progression Through Regulation Of Β-Site Amyloid Precursor Protein-Cleaving Enzyme 1, Wang-Xia Wang, Bernard W. Rajeev, Arnold J. Stromberg, Na Ren, Guiliang Tang, Qingwei Huang, Isidore Rigoutsos, Peter T. Nelson

Sanders-Brown Center on Aging Faculty Publications

MicroRNAs (miRNAs) are small regulatory RNAs that participate in posttranscriptional gene regulation in a sequence-specific manner. However, little is understood about the role(s) of miRNAs in Alzheimer's disease (AD). We used miRNA expression microarrays on RNA extracted from human brain tissue from the University of Kentucky Alzheimer's Disease Center Brain Bank with near-optimal clinicopathological correlation. Cases were separated into four groups: elderly nondemented with negligible AD-type pathology, nondemented with incipient AD pathology, mild cognitive impairment (MCI) with moderate AD pathology, and AD. Among the AD-related miRNA expression changes, miR-107 was exceptional because miR-107 levels decreased significantly even in patients with …

Neuropathological Findings Processed By Artificial Neural Networks (Anns) Can Perfectly Distinguish Alzheimer's Patients From Controls In The Nun Study, Enzo Grossi, Massimo P. Buscema, David Snowdon, Piero Antuono

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Many reports have described that there are fewer differences in AD brain neuropathologic lesions between AD patients and control subjects aged 80 years and older, as compared with the considerable differences between younger persons with AD and controls. In fact some investigators have suggested that since neurofibrillary tangles (NFT) can be identified in the brains of non-demented elderly subjects they should be considered as a consequence of the aging process. At present, there are no universally accepted neuropathological criteria which can mathematically differentiate AD from healthy brain in the oldest old. The aim of this study is to discover …