Medicine and Health Sciences Commons^™

Kl-Vs Heterozygosity Is Associated With Lower Amyloid-Dependent Tau Accumulation And Memory Impairment In Alzheimer’S Disease, Julia Neitzel, Nicolai Franzmeier, Anna Rubinski, Martin Dichgans, Matthias Brendel, Michael Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, Andrew J. Saykin, John Morris, Leslie M. Shaw, Enchi Liu, Tom Montine, Ronald G. Thomas, Michael Donohue, Sarah Walter, Devon Gessert, Tamie Sather, Gus Jiminez, Danielle Harvey, Matthew Bernstein, Nick Fox, Paul Thompson, Norbert Schuff, Charles Decarli, Bret Borowski

Medical Biophysics Publications

Klotho-VS heterozygosity (KL-VShet) is associated with reduced risk of Alzheimer’s disease (AD). However, whether KL-VShet is associated with lower levels of pathologic tau, i.e., the key AD pathology driving neurodegeneration and cognitive decline, is unknown. Here, we assessed the interaction between KL-VShet and levels of beta-amyloid, a key driver of tau pathology, on the levels of PET-assessed neurofibrillary tau in 551 controls and patients across the AD continuum. KL-VShet showed lower cross-sectional and longitudinal increase in tau-PET per unit increase in amyloid-PET when compared to that of non-carriers. This association of KL-VShet on tau-PET was stronger in Klotho mRNA-expressing brain …

Using Imputation To Provide Harmonized Longitudinal Measures Of Cognition Across Aibl And Adni, Rosita Shishegar, Timothy Cox, David Rolls, Pierrick Bourgeat, Vincent Doré, Fiona Lamb, Joanne Robertson, Simon M. Laws, Tenielle Porter, Jurgen Fripp, Duygu Tosun, Paul Maruff, Greg Savage, Christopher C. Rowe, Colin L. Masters, Michael W. Weiner, Victor L. Villemagne, Samantha C. Burnham

Research outputs 2014 to 2021

To improve understanding of Alzheimer’s disease, large observational studies are needed to increase power for more nuanced analyses. Combining data across existing observational studies represents one solution. However, the disparity of such datasets makes this a non-trivial task. Here, a machine learning approach was applied to impute longitudinal neuropsychological test scores across two observational studies, namely the Australian Imaging, Biomarkers and Lifestyle Study (AIBL) and the Alzheimer's Disease Neuroimaging Initiative (ADNI) providing an overall harmonised dataset. MissForest, a machine learning algorithm, capitalises on the underlying structure and relationships of data to impute test scores not measured in one study aligning …

Microbial Influence On Alzheimer's Disease, Ashley N. Hamby

The Cardinal Edge

No abstract provided.

Random Forest-Integrated Analysis In Ad And Late Brain Transcriptome-Wide Data To Identify Disease-Specific Gene Expression, Xinxing Wu, Chong Peng, Peter T. Nelson, Qiang Cheng

Sanders-Brown Center on Aging Faculty Publications

Alzheimer's disease (AD) is a complex neurodegenerative disorder that affects thinking, memory, and behavior. Limbic-predominant age-related TDP-43 encephalopathy (LATE) is a recently identified common neurodegenerative disease that mimics the clinical symptoms of AD. The development of drugs to prevent or treat these neurodegenerative diseases has been slow, partly because the genes associated with these diseases are incompletely understood. A notable hindrance from data analysis perspective is that, usually, the clinical samples for patients and controls are highly imbalanced, thus rendering it challenging to apply most existing machine learning algorithms to directly analyze such datasets. Meeting this data analysis challenge is …

Q134r: Small Chemical Compound With Nfat Inhibitory Properties Improves Behavioral Performance And Synapse Function In Mouse Models Of Amyloid Pathology, Pradoldej Sompol, Jenna L. Gollihue, Susan D. Kraner, Irina A. Artiushin, Ryan A. Cloyd, Emad Chishti, Shon A. Koren, Grant K. Nation, Jose F. Abisambra, Orsolya Huzian, Lajos I. Nagy, Miklos Santha, Laszlo Hackler Jr., Laszlo G. Puskas, Christopher M. Norris

Sanders-Brown Center on Aging Faculty Publications

Inhibition of the protein phosphatase calcineurin (CN) ameliorates pathophysiologic and cognitive changes in aging rodents and mice with aging-related Alzheimer's disease (AD)-like pathology. However, concerns over adverse effects have slowed the transition of common CN-inhibiting drugs to the clinic for the treatment of AD and AD-related disorders. Targeting substrates of CN, like the nuclear factor of activated T cells (NFATs), has been suggested as an alternative, safer approach to CN inhibitors. However, small chemical inhibitors of NFATs have only rarely been described. Here, we investigate a newly developed neuroprotective hydroxyquinoline derivative (Q134R) that suppresses NFAT signaling, without inhibiting CN activity. …

Myeloid Arginase 1 Insufficiency Exacerbates Amyloid-Β Associated Neurodegenerative Pathways And Glial Signatures In A Mouse Model Of Alzheimer’S Disease: A Targeted Transcriptome Analysis, Chao Ma, Jerry B. Hunt, Andrii Kovalenko, Huimin Liang, Maj-Linda B. Selenica, Michael B. Orr, Bei Zhang, John C. Gensel, David J. Feola, Marcia N. Gordon, Dave Morgan, Paula C. Bickford, Daniel C. Lee

Sanders-Brown Center on Aging Faculty Publications

Brain myeloid cells, include infiltrating macrophages and resident microglia, play an essential role in responding to and inducing neurodegenerative diseases, such as Alzheimer’s disease (AD). Genome-wide association studies (GWAS) implicate many AD casual and risk genes enriched in brain myeloid cells. Coordinated arginine metabolism through arginase 1 (Arg1) is critical for brain myeloid cells to perform biological functions, whereas dysregulated arginine metabolism disrupts them. Altered arginine metabolism is proposed as a new biomarker pathway for AD. We previously reported Arg1 deficiency in myeloid biased cells using lysozyme M (LysM) promoter-driven deletion worsened amyloidosis-related neuropathology and behavioral impairment. However, …

Alzheimer’S And Patient Caregiver Burnout: A Comprehensive Review Of The Literature, Madeline J. Hekeler

Senior Honors Projects, 2020-current

The term ‘silent epidemic’ has become fitting for Alzheimer’s disease, as it is now the sixth leading cause of death in the US. Caring for AD patients at home in the US costs billions of dollars each year. The current comprehensive literature review discusses the background/history of AD, pathology and modes of transmission of AD, behavioral and natural risk factors, prevention and treatment options, and how the aforementioned factors contribute to caregiver burnout and subsequently affect the AD patient. The extensive examination of the literature determined several gaps to be addressed. More specifically, burnout among AD caregivers has become an …

Water Exchange Rate Across The Blood-Brain Barrier Is Associated With Csf Amyloid-Β 42 In Healthy Older Adults, Brian T. Gold, Xingfeng Shao, Tiffany L. Sudduth, Gregory A. Jicha, Donna M. Wilcock, Elayna R. Seago, Danny J. J. Wang

Sanders-Brown Center on Aging Faculty Publications

INTRODUCTION: We tested if water exchange across the blood-brain barrier (BBB), estimated with a noninvasive magnetic resonance imaging (MRI) technique, is associated with cerebrospinal fluid (CSF) biomarkers of Alzheimer's disease (AD) and neuropsychological function.

METHODS: Forty cognitively normal older adults (67–86 years old) were scanned with diffusion‐prepared, arterial spin labeling (DP‐ASL), which estimates water exchange rate across the BBB (k_w). Participants also underwent CSF draw and neuropsychological testing. Multiple linear regression models were run with kw as a predictor of CSF concentrations and neuropsychological scores.

RESULTS: In multiple brain regions, BBB kw was positively associated with CSF amyloid …

Investigating Diffusion Tensor Imaging Correlates Of Cognitive Impairment In Idiopathic Normal Pressure Hydrocephalus And Alzheimer's Disease, Omar Hasan, Omar Hasan

Dissertations & Theses (Open Access)

Modest expansion of the human brain cerebrospinal fluid (CSF)-filled ventricles is normal with aging, and because of this, it can be difficult for physicians to accurately diagnose and treat enlarged ventricles (ventriculomegaly), called hydrocephalus¹ (fluid or water in the brain) Ventriculomegaly occurs due to an obstruction (such as a blood clot or tumor), or a change in CSF absorption². Primary hydrocephalus, also called idiopathic normal pressure hydrocephalus (iNPH), is non-obstructive and may be comorbid with other neurodegenerative diseases such as Alzheimer’s disease (AD) or frontotemporal dementia (FTD). Clinically, it can be difficult to tell whether the pathophysiological …

Development Of A Novel Cognitive-Motor Dual Task Assessment Battery In Neurodegenerative Disease, Jason Longhurst

UNLV Theses, Dissertations, Professional Papers, and Capstones

Automaticity --- the ability to perform a task with directing attentional resources to its completion --- is commonly reduced among individuals with neurodegenerative diseases. These automaticity deficits result in impaired functional and daily activities and are sensitive to subtle, subclinical impairments. However, current measurement of automaticity by dual task paradigms is methodologically limited. In order to gain insight into the current state of the literature regarding cognitive-motor interference in symptomatic and prodromal neurodegenerative disease, the author of this dissertation conducted a scoping review (Chapter 1). To address the methodological limitations of current measurement of automaticity, a new measurement tool was …

Spon1 Is Associated With Amyloid-Β And Apoe Ε4-Related Cognitive Decline In Cognitively Normal Adults, Shane Fernandez, Samantha C. Burnham, Lidija Milicic, Greg Savage, Paul Maruff, Madeline Peretti, Hamid R. Sohrabi, Yen Ying Lim, Michael Weinborn, David Ames, Colin L. Masters, Ralph N. Martins, Stephanie Rainey-Smith, Christopher C. Rowe, Olivier Salvado, David Groth, Giuseppe Verdile, Victor L. Villemagne, Tenielle Porter, Simon M. Laws

Research outputs 2014 to 2021

Background: Genetic variation in Spondin-1, specifically rs11023139, has been associated with reduced rates of cognitive decline in individuals with Alzheimer's disease. Objective: The aim of this study was to assess whether the association was present in cognitively normal older adults. Methods: Longitudinal cognitive decline was investigated using linear mixed modelling in a cohort of 590 cognitively normal older adults enrolled in the Australian Imaging, Biomarkers and Lifestyle Study. Results: No independent effect of Spondin-1 rs11023139 on cognitive decline was observed. However, significant associations were observed for the interaction between Apolipoprotein E (APOE) ϵ4 and rs11023139 in individuals with high amyloid-β …

Intake Of Products Containing Anthocyanins, Flavanols, And Flavanones, And Cognitive Function: A Narrative Review, Samantha L. Gardener, Stephanie R. Rainey-Smith, Michael Weinborn, Catherine P. Bondonno, Ralph N. Martins

Research outputs 2014 to 2021

The purpose of this review is to examine human research studies published within the past 6 years which evaluate the role of anthocyanin, flavanol, and flavanone consumption in cognitive function, and to discuss potential mechanisms of action underlying any observed benefits. Evidence to date suggests the consumption of flavonoid-rich foods, such as berries and cocoa, may have the potential to limit, or even reverse, age-related declines in cognition. Over the last 6 years, the flavonoid subgroups of anthocyanins, flavanols, and flavanones have been shown to be beneficial in terms of conferring neuroprotection. The mechanisms by which flavonoids positively modulate cognitive …

Potential Of Sorghum Polyphenols To Prevent And Treat Alzheimer's Disease: A Review Article, Nasim Rezaee, Warnakulasuriya Mary Ann Dipika Fernando, Eugene Hone, Hamid R. Sohrabi, Stuart K. Johnson, Stuart Gunzburg, Ralph Martins

Research outputs 2014 to 2021

Alzheimer’s disease (AD) is characterized by the excessive deposition of extracellular amyloid-beta peptide (Aβ) and the build-up of intracellular neurofibrillary tangles containing hyperphosphorylated tau proteins. This leads to neuronal damage, cell death and consequently results in memory and learning impairments leading to dementia. Although the exact cause of AD is not yet clear, numerous studies indicate that oxidative stress, inflammation, and mitochondrial dysfunction significantly contribute to its onset and progression. There is no effective therapeutic approach to stop the progression of AD and its associated symptoms. Thus, early intervention, preferably, pre-clinically when the brain is not significantly affected, is a …

Polygenic Score Modifies Risk For Alzheimer's Disease In Ε4 Homozygotes At Phenotypic Extremes, Aamira J. Huq, Brian Fulton-Howard, Moeen Riaz, Simon Laws, Robert Sebra, Joanne Ryan, Alzheimer’S Disease Genetics Consortium, Alan E. Renton, Alison M. Goate, Colin L. Masters, Elsdon Storey, Raj C. Shah, Anne Murray, John Mcneil, Ingrid Winship, Paul A. Jones

Research outputs 2014 to 2021

Introduction: Diversity in cognition among apolipoprotein E () ε4 homozygotes can range from early-onset Alzheimer's disease (AD) to a lifetime with no symptoms. Methods: We evaluated a phenotypic extreme polygenic risk score (PRS) for AD between cognitively healthy ε4 homozygotes aged ≥75 years (n = 213) and early-onset ε4 homozygote AD cases aged ≤65 years (n = 223) as an explanation for this diversity. Results: The PRS for AD was significantly higher in ε4 homozygote AD cases compared to older cognitively healthy ε4/ε4 controls (odds ratio [OR] 8.39; confidence interval [CI] 2.0-35.2; = .003). The difference in the same PRS …

The Support Person's Preferences And Perspectives Of Physical Activity Programs For Older Adults With Cognitive Impairment, Terence W. H. Chong, Emily You, Kathryn A. Ellis, Kay L. Cox, Karra D. Harrington, Stephanie R. Rainey-Smith, David Ames, Nicola T. Lautenschlager, Aibl Research Group

Research outputs 2014 to 2021

Objectives: Physical activity (PA) is beneficial for older adults' cognition. There is limited research investigating perspectives of support persons (SPs) of next-of-kins (NOKs) with cognitive impairment. This exploratory study aimed to investigate perspectives of SPs of older adults with Alzheimer's Dementia (AD) or Mild Cognitive Impairment (MCI). Methods: A telephone survey of 213 SPs of NOKs from the Australian Imaging, Biomarkers and Lifestyle Flagship Study of Ageing (AIBL) was undertaken to quantitatively assess SPs' beliefs and knowledge about PA benefits, current PA level of their NOK, and PA program preferences. The contribution of age, gender, diagnosis and mental health symptoms …

Fifteen Years Of The Australian Imaging, Biomarkers And Lifestyle (Aibl) Study: Progress And Observations From 2,359 Older Adults Spanning The Spectrum From Cognitive Normality To Alzheimer's Disease, Christopher Fowler, Stephanie R. Rainey-Smith, Sabine Bird, Julia Bomke, Pierrick Bourgeat, Belinda M. Brown, Samantha C. Burnham, Ashley I. Bush, Carolyn Chadunow, Steven Collins, James Doecke, Vincent Doré, Kathryn A. Ellis, Lis Evered, Amir Fazlollahi, Jurgen Fripp, Samantha L. Gardener, Simon Gibson, Robert Grenfell, Elise Harrison, Richard Head, Liang Jin, Adrian Kamer, Fiona Lamb, Nicola T. Lautenschlager, Simon M. Laws, Qiao-Xin Li, Lucy Lim, Yen Ying Lim, Andrea Louey, S. Lance Macaulay, Lucy Mackintosh, Ralph N. Martins, Paul Maruff, Colin L. Masters, Simon Mcbride, Lidija Milicica, Madeline Peretti, Kelly Pertile, Tenielle Porter, Morgan Radler, Alan Rembach, Joanne Robertson, Mark Rodrigues, Christopher C. Rowe, Rebecca Rumble, Olivier Salvado, Greg Savage, Brendan Silbert, Magdalene Soh, Hamid R. Sohrabi, Kevin Taddei, Tania Taddei, Christine Thai, Brett Trounson, Regan Tyrrell, Michael Vacher, Shiji Varghese, Victor L. Villemagne, Michael Weinborn, Michael Woodward, Ying Xia, David Ames, Aibl Investigators

Research outputs 2014 to 2021

Background: The Australian Imaging, Biomarkers and Lifestyle (AIBL) Study commenced in 2006 as a prospective study of 1,112 individuals (768 cognitively normal (CN), 133 with mild cognitive impairment (MCI), and 211 with Alzheimer's disease dementia (AD)) as an 'Inception cohort' who underwent detailed ssessments every 18 months. Over the past decade, an additional 1247 subjects have been added as an 'Enrichment cohort' (as of 10 April 2019). Objective: Here we provide an overview of these Inception and Enrichment cohorts of more than 8,500 person-years of investigation. Methods: Participants underwent reassessment every 18 months including comprehensive cognitive testing, neuroimaging (magnetic resonance …

Effects Of Tacrolimus On C-Fos In Hippocampus And Memory Performances Instreptozotocin Model Of Alzheimer's Disease Of Rats, Ayşe Köylü, Berri̇n Zühal Altunkaynak, Burcu Deli̇baş

Turkish Journal of Medical Sciences

Background/aim: Calcineurin, an inhibitor of calcium dependent phosphatase is highly presented in a brain of an Alzheimer?s disease. Aging brain gets more sensitive to hyperactivation of calcineurin, and this event causes tau neurofibrillary plaque accumulation, which is one of the outcomes of this disease. The regions of hippocampus are much effected from the results of this process. Our hypothesis is that a calcineurin inhibitor, tacrolimus, could prevent the accumulation and the decrease of the neuronal cells. Therefore, this immunosuppressive drug could be a candidate for an early treatment of Alzheimer disease. Materials and methods: Fifteen male Wistar albino rats were …

Investigating Auditory Electrophysiological Measures Of Participants With Mild Cognitive Impairment And Alzheimer's Disease: A Systematic Review And Meta-Analysis Of Event-Related Potential Studies, Hadeel Y. Tarawneh, Wilhelmina H. A. M. Mulders, Hamid R. Sohrabi, Ralph N. Martins, Dona M. P. Jayakody

Research outputs 2014 to 2021

Background: Objectively measuring auditory functions has been proposed as an avenue in differentiating normal age-related cognitive dysfunction from Alzheimer's disease (AD) and its prodromal states. Previous research has suggested auditory event-related potentials (AERPs) to be non-invasive, cost-effective, and efficient biomarkers for the diagnosis of AD. Objective: The objective of this paper is to review the published literature on AERPs measures in older adults diagnosed with AD and those at higher risk of developing AD, i.e., mild cognitive impairment (MCI) and subjective cognitive decline. Methods: The search was performed on six major electronic databases (Ovid MEDLINE, OVID EMBASE, PsycINFO, PubMed, Scopus, …