Geriatrics Commons^™

Inhibition Of Soluble Tumor Necrosis Factor Ameliorates Synaptic Alterations And Ca2+ Dysregulation In Aged Rats, Diana M. Sama, Hafiz Mohmmad Abdul, Jennifer L. Furman, Irina A. Artiushin, David E. Szymkowski, Stephen W. Scheff, Christopher M. Norris

Graduate Center for Gerontology Faculty Publications

The role of tumor necrosis factor α (TNF) in neural function has been investigated extensively in several neurodegenerative conditions, but rarely in brain aging, where cognitive and physiologic changes are milder and more variable. Here, we show that protein levels for TNF receptor 1 (TNFR1) are significantly elevated in the hippocampus relative to TNF receptor 2 (TNFR2) in aged (22 months) but not young adult (6 months) Fischer 344 rats. To determine if altered TNF/TNFR1 interactions contribute to key brain aging biomarkers, aged rats received chronic (4-6 week) intracranial infusions of XPro1595: a soluble dominant negative TNF that preferentially inhibits …

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 …

Elucidating The Mechanisms Underlying Alzheimer's Disease-Associated Genetic Polymorphisms, Steven Estus

Sanders-Brown Center on Aging Presentations

Recent genome-wide association studies (GWAS) have yielded a bounty of single nucleotide polymorphisms (SNP)s related to Alzheimer's disease (AD) or conditions associated with AD. Here, we will present several vignettes that illustrate approaches to use these results to clarify AD-related pathways and potential therapeutics

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 …

Mild Cognitive Impairment: Statistical Models Of Transition Using Longitudinal Clinical Data, Erin L. Abner, Richard J. Kryscio, Gregory E. Cooper, David W. Fardo, Gregory A. Jicha, Marta S. Mendiondo, Peter T. Nelson, Charles D. Smith, Linda J. Van Eldik, Lijie Wan, Frederick A. Schmitt

Sanders-Brown Center on Aging Faculty Publications

Mild cognitive impairment (MCI) refers to the clinical state between normal cognition and probable Alzheimer's disease (AD), but persons diagnosed with MCI may progress to non-AD forms of dementia, remain MCI until death, or recover to normal cognition. Risk factors for these various clinical changes, which we term "transitions," may provide targets for therapeutic interventions. Therefore, it is useful to develop new approaches to assess risk factors for these transitions. Markov models have been used to investigate the transient nature of MCI represented by amnestic single-domain and mixed MCI states, where mixed MCI comprised all other MCI subtypes based on …

Microglial P38Α Mapk Is Critical For Lps-Induced Neuron Degeneration, Through A Mechanism Involving Tnfα, Bin Xing, Adam D. Bachstetter, Linda J. Van Eldik

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: The p38α MAPK isoform is a well-established therapeutic target in peripheral inflammatory diseases, but the importance of this kinase in pathological microglial activation and detrimental inflammation in CNS disorders is less well understood. To test the role of the p38α MAPK isoform in microglia-dependent neuron damage, we used primary microglia from wild-type (WT) or p38α MAPK conditional knockout (KO) mice in co-culture with WT cortical neurons, and measured neuron damage after LPS insult.

RESULTS: We found that neurons in co-culture with p38α-deficient microglia were protected against LPS-induced synaptic loss, neurite degeneration, and neuronal death. The involvement of the proinflammatory …

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 …

Evaluation Of The Global Association Between Cholesterol-Associated Polymorphisms And Alzheimer's Disease Suggests A Role For Rs3846662 And Hmgcr Splicing In Disease Risk, Christopher R. Simmons, Fanggeng Zou, Steven G Younkin, Steven Estus

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Recent genome-wide association studies (GWAS) have identified single nucleotide polymorphisms (SNP)s that are essentially unequivocally associated with peripheral cholesterol. Since the alleles of the APOE gene, which modulate peripheral cholesterol metabolism, and midlife plasma cholesterol are both associated with Alzheimer's disease (AD) risk, we have evaluated the hypothesis that SNPs associated with plasma cholesterol are also associated with AD.

RESULTS: Seventeen non-APOE SNPs reproducibly associated with cholesterol per GWAS were tested for association with AD in ~2,000 AD and ~4,000 non-AD subjects. As a group, these SNPs are associated with AD. Two SNPs in particular, rs3846662 and rs1532085, are …

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 …

Microglial P38Α Mapk Is A Key Regulator Of Proinflammatory Cytokine Up-Regulation Induced By Toll-Like Receptor (Tlr) Ligands Or Beta-Amyloid (Aβ), Adam D. Bachstetter, Bin Xing, Lucia De Almeida, Edgardo R. Dimayuga, D. Martin Watterson, Linda J. Van Eldik

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Overproduction of proinflammatory cytokines from activated microglia has been implicated as an important contributor to pathophysiology progression in both acute and chronic neurodegenerative diseases. Therefore, it is critical to elucidate intracellular signaling pathways that are significant contributors to cytokine overproduction in microglia exposed to specific stressors, especially pathways amenable to drug interventions. The serine/threonine protein kinase p38α MAPK is a key enzyme in the parallel and convergent intracellular signaling pathways involved in stressor-induced production of IL-1β and TNFα in peripheral tissues, and is a drug development target for peripheral inflammatory diseases. However, much less is known about the quantitative …

Analyzing The Impact Of 23 Mg/Day Donepezil On Language Dysfunction In Moderate To Severe Alzheimer's Disease, Steven H. Ferris, Frederick A. Schmitt, Judith Saxton, Sharon Richardson, Joan Mackell, Yijun Sun, Yikang Xu

Sanders-Brown Center on Aging Faculty Publications

INTRODUCTION: Progressive language impairment is among the primary components of cognitive decline in Alzheimer's disease (AD). Because expressive and receptive language help to maintain emotional connections to caregivers and support the management of AD patients' functional needs, language plays a critical role in patients' emotional and physical health. Using data from a large prospective clinical trial comparing two doses of donepezil in patients with moderate to severe AD, we performed a post hoc analysis to determine whether a higher dose of donepezil was associated with greater benefits in language function.

METHODS: In the original randomized, double-blind clinical trial, 1,467 patients …

Rheumatoid Arthritis-Associated Polymorphisms Are Not Protective Against Alzheimer's Disease, Christopher R. Simmons, Fanggeng Zou, Steven G Younkin, Steven Estus

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Rheumatoid arthritis (RA) and Alzheimer's disease (AD) are inversely associated. To test the hypothesis that genetic elements associated with increased RA risk are associated with decreased AD risk, we evaluated RA genetic risk factors recently identified in genome-wide association studies (GWAS) for their association with AD in a two-stage, case-control analysis.

RESULTS: In our Stage 1 analysis of ~800 AD and ~1,200 non-AD individuals, three of seventeen RA-associated SNPs were nominally associated with AD (p < 0.05) with one SNP, rs2837960, retaining significance after correction for multiple testing (p = 0.03). The rs2837960_G (minor) allele, which is associated with increased RA risk, was associated with increased AD risk. Analysis of these three SNPs in a Stage 2 population, consisting of ~1,100 AD and ~2,600 non-AD individuals, did not confirm their association with AD. Analysis of Stage 1 and 2 combined suggested that rs2837960 shows a trend for association with AD. When the Stage 2 population was age-matched for the Stage 1 population, rs2837960 exhibited a non-significant trend with AD. Combined analysis of Stage 1 and the age-matched Stage 2 subset showed a significant association of rs2837960 with AD (p = 0.002, OR 1.24) that retained significance following correction for age, sex and APOE (p = 0.02, OR = 1.20). Rs2837960 is near BACE2, which encodes an aspartic protease capable of processing the AD-associated amyloid precursor protein. Testing for an association between rs2837960 and the expression of BACE2 isoforms in human brain, we observed a trend between rs2837960 and the total expression of BACE2 and the expression of a BACE2 transcript lacking exon 7 (p = 0.07 and 0.10, respectively).

CONCLUSIONS: RA-associated SNPs are generally not associated with AD. Moreover, rs2837960_G is associated with increased risk of both RA and, in individuals less than …

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 …

Cx3cl1 Reduces Neurotoxicity And Microglial Activation In A Rat Model Of Parkinson's Disease, Mibel M. Pabon, Adam D. Bachstetter, Charles E. Hudson, Carmelina Gemma, Paula C. Bickford

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Parkinson's disease is characterized by a progressive loss of dopaminergic neurons in the substantia nigra. The cause of the neurodegeneration is unknown. Neuroinflammation has been clearly shown in Parkinson's disease and may be involved in the progressive nature of the disease. Microglia are capable of producing neuronal damage through the production of bioactive molecules such as cytokines, as well as reactive oxygen species (ROS), and nitric oxide (NO). The inflammatory response in the brain is tightly regulated at multiple levels. One form of immune regulation occurs via neurons. Fractalkine (CX3CL1), produced by neurons, suppresses the activation of microglia. CX3CL1 …

Attention-Deficit/Hyperactivity Disorder In Childhood Is Associated With Cognitive Test Profiles In The Geriatric Population But Not With Mild Cognitive Impairment Or Alzheimer's Disease, N. Ivanchak, Erin L. Abner, S. A. Carr, S. J. Freeman, A. Seybert, John Ranseen, Gregory A. Jicha

Sanders-Brown Center on Aging Faculty Publications

The frequency of ADHD in the aging population and its relationship to late-life cognitive decline has not been studied previously. To address this gap in our understanding, the Wender-Utah ADHD Rating scale (WURS) was administered to 310 geriatric subjects with cognitive status ranging from normal cognition to mild cognitive impairment to overt dementia. The frequency of WURS-positive ADHD in this sample was 4.4%. WURS scores were not related to cognitive diagnoses, but did show nonlinear associations with tasks requiring sustained attention. The frequency of ADHD appears stable across generations and does not appear to be associated with MCI or dementia …

Dementia Caregiving Outcomes: The Impact Of Caregiving Onset, Role Occupancy, And Care-Recipient Decline, Katherina Nikzad-Terhune

University of Kentucky Doctoral Dissertations

Dementia is characterized as a progressive loss of brain function that results in the deterioration of many cognitive and physical abilities. Alzheimer’s disease (AD) is the most common form of dementia, causing steady declines in memory, functional abilities, and mental functioning. With a projected increase of degenerative illnesses, such as AD, family caregiving for individuals with the disease is also steadily increasing. Caring for an individual with AD has been characterized as a “career,” and within this career are a number of key transitions, including the onset of caregiving. Preexisting caregiving research reveals a number of negative consequences for AD …

Conformation Dependent Monoclonal Antibodies Distinguish Different Replicating Strains Or Conformers Of Prefibrillar Aβ Oligomers, Rakez Kayed, Isabel Canto, Leonid Breydo, Suhail Rasool, Tamas Lukacsovich, Jessica Wu, Ricardo Albay, Anna Pensalfini, Stephen Yeung, Elizabeth Head, J. Lawrence Marsh, Charles Glabe

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Age-related neurodegenerative diseases share a number of important pathological features, such as accumulation of misfolded proteins as amyloid oligomers and fibrils. Recent evidence suggests that soluble amyloid oligomers and not the insoluble amyloid fibrils may represent the primary pathological species of protein aggregates.

RESULTS: We have produced several monoclonal antibodies that specifically recognize prefibrillar oligomers and do not recognize amyloid fibrils, monomer or natively folded proteins. Like the polyclonal antisera, the individual monoclonals recognize generic epitopes that do not depend on a specific linear amino acid sequence, but they display distinct preferences for different subsets of prefibrillar oligomers. Immunological …

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 …

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 …

Focus On Rna Isolation: Obtaining Rna For Microrna (Mirna) Expression Profiling Analyses Of Neural Tissue, Wang-Xia Wang, Bernard R. Wilfred, Donald A. Baldwin, R. Benjamin Isett, Na Ren, Arnold J. Stromberg, Peter T. Nelson

Sanders-Brown Center on Aging Faculty Publications

MicroRNAs (miRNAs) are present in all known plant and animal tissues and appear to be somewhat concentrated in the mammalian nervous system. Many different miRNA expression profiling platforms have been described. However, relatively little research has been published to establish the importance of 'upstream' variables in RNA isolation for neural miRNA expression profiling. We tested whether apparent changes in miRNA expression profiles may be associated with tissue processing, RNA isolation techniques, or different cell types in the sample. RNA isolation was performed on a single brain sample using eight different RNA isolation methods, and results were correlated using a conventional …

Focal Cerebral Ischemia In The Tnfalpha-Transgenic Rat, L. Creed Pettigrew, Mark S. Kindy, Stephen W. Scheff, Joe E. Springer, Richard J. Kryscio, Yizhao Li, David S. Grass

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: To determine if chronic elevation of the inflammatory cytokine, tumor necrosis factor-alpha (TNFalpha), will affect infarct volume or cortical perfusion after focal cerebral ischemia.

METHODS: Transgenic (TNFalpha-Tg) rats overexpressing the murine TNFalpha gene in brain were prepared by injection of mouse DNA into rat oocytes. Brain levels of TNFalpha mRNA and protein were measured and compared between TNFalpha-Tg and non-transgenic (non-Tg) littermates. Mean infarct volume was calculated 24 hours or 7 days after one hour of reversible middle cerebral artery occlusion (MCAO). Cortical perfusion was monitored by laser-Doppler flowmetry (LDF) during MCAO. Cortical vascular density was quantified by stereology. …

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 …

Micrornas (Mirnas) In Neurodegenerative Diseases, Peter T. Nelson, Wang-Xia Wang, Bernard W. Rajeev

Sanders-Brown Center on Aging Faculty Publications

Aging-related neurodegenerative diseases (NDs) are the culmination of many different genetic and environmental influences. Prior studies have shown that RNAs are pathologically altered during the inexorable course of some NDs. Recent evidence suggests that microRNAs (miRNAs) may be a contributing factor in neurodegeneration. miRNAs are brain-enriched, small (~22 nucleotides) non-coding RNAs that participate in mRNA translational regulation. Although discovered in the framework of worm development, miRNAs are now appreciated to play a dynamic role in many mammalian brain-related biochemical pathways, including neuroplasticity and stress responses. Research about miRNAs in the context of neurodegeneration is accumulating rapidly, and the goal of …

Energizing Mirna Research: A Review Of The Role Of Mirnas In Lipid Metabolism, With A Prediction That Mir-103/107 Regulates Human Metabolic Pathways, Bernard R. Wilfred, Wang-Xia Wang, Peter T. Nelson

Sanders-Brown Center on Aging Faculty Publications

MicroRNAs (miRNAs) are powerful regulators of gene expression. Although first discovered in worm larvae, miRNAs play fundamental biological roles-including in humans-well beyond development. MiRNAs participate in the regulation of metabolism (including lipid metabolism) for all animal species studied. A review of the fascinating and fast-growing literature on miRNA regulation of metabolism can be parsed into three main categories: (1) adipocyte biochemistry and cell fate determination; (2) regulation of metabolic biochemistry in invertebrates; and (3) regulation of metabolic biochemistry in mammals. Most research into the 'function' of a given miRNA in metabolic pathways has concentrated on a given miRNA acting upon …

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 …

Similar Promotion Of Abeta1-42 Fibrillogenesis By Native Apolipoprotein E Epsilon3 And Epsilon4 Isoforms, David Sweeney, Ralph Martins, Harry Levine, Jonathan D. Smith, Sam Gandy

Sanders-Brown Center on Aging Faculty Publications

The apolipoprotein E epsilon4 allele contributes to the genetic susceptibility underlying a large proportion (~40-60%) of typical, sporadic Alzheimer disease. Apolipoprotein E deficient mice made transgenic for human apolipoprotein E epsilon4 accumulate excess cerebral amyloid when compared to similarly prepared mice expressing human apolipoprotein E epsilon3. Therefore, it is important to search for relevant interactions(s) between apolipoprotein E epsilon4 and Abeta in order to clarify the biological role for apolipoprotein E epsilon4 in Alzheimer disease. Using a thioflavine T (ThT)-based assay, we have investigated the effects of native human apolipoprotein E isoforms on the kinetics of Abeta fibrillogenesis. No obvious …