Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 9 of 9

Full-Text Articles in Entire DC Network

Dystrophic Microglia Are Associated With Neurodegenerative Disease And Not Healthy Aging In The Human Brain, Ryan K. Shahidehpour, Rebecca E. Higdon, Nicole G. Crawford, Janna H. Neltner, Eseosa T. Ighodaro, Ela Patel, Douglas Price, Peter T. Nelson, Adam D. Bachstetter Jan 2021

Dystrophic Microglia Are Associated With Neurodegenerative Disease And Not Healthy Aging In The Human Brain, Ryan K. Shahidehpour, Rebecca E. Higdon, Nicole G. Crawford, Janna H. Neltner, Eseosa T. Ighodaro, Ela Patel, Douglas Price, Peter T. Nelson, Adam D. Bachstetter

Spinal Cord and Brain Injury Research Center Faculty Publications

Loss of physiological microglial function may increase the propagation of neurodegenerative diseases. Cellular senescence is a hallmark of aging; thus, we hypothesized age could be a cause of dystrophic microglia. Stereological counts were performed for total microglia, 2 microglia morphologies (hypertrophic and dystrophic) across the human lifespan. An age-associated increase in the number of dystrophic microglia was found in the hippocampus and frontal cortex. However, the increase in dystrophic microglia was proportional to the age-related increase in the total number of microglia. Thus, aging alone does not explain the presence of dystrophic microglia. We next tested if dystrophic microglia could …


Brain Structure Changes Over Time In Normal And Mildly Impaired Aged Persons, Charles D. Smith, Linda J. Van Eldik, Gregory A. Jicha, Frederick A. Schmitt, Peter T. Nelson, Erin L. Abner, Richard J. Kryscio, Richard R. Murphy, Anders H. Andersen May 2020

Brain Structure Changes Over Time In Normal And Mildly Impaired Aged Persons, Charles D. Smith, Linda J. Van Eldik, Gregory A. Jicha, Frederick A. Schmitt, Peter T. Nelson, Erin L. Abner, Richard J. Kryscio, Richard R. Murphy, Anders H. Andersen

Neurology Faculty Publications

Structural brain changes in aging are known to occur even in the absence of dementia, but the magnitudes and regions involved vary between studies. To further characterize these changes, we analyzed paired MRI images acquired with identical protocols and scanner over a median 5.8-year interval. The normal study group comprised 78 elders (25M 53F, baseline age range 70-78 years) who underwent an annual standardized expert assessment of cognition and health and who maintained normal cognition for the duration of the study. We found a longitudinal grey matter (GM) loss rate of 2.56 ± 0.07 ml/year (0.20 ± 0.04%/year) and a …


Tdp-43 Proteinopathy In Aging: Associations With Risk-Associated Gene Variants And With Brain Parenchymal Thyroid Hormone Levels, Peter T. Nelson, Zsombor Gal, Wang-Xia Wang, Dana M. Niedowicz, Sergey C. Artiushin, Samuel Wycoff, Angela Wei, Gregory A. Jicha, David W. Fardo May 2019

Tdp-43 Proteinopathy In Aging: Associations With Risk-Associated Gene Variants And With Brain Parenchymal Thyroid Hormone Levels, Peter T. Nelson, Zsombor Gal, Wang-Xia Wang, Dana M. Niedowicz, Sergey C. Artiushin, Samuel Wycoff, Angela Wei, Gregory A. Jicha, David W. Fardo

Pathology and Laboratory Medicine Faculty Publications

TDP-43 proteinopathy is very prevalent among the elderly (affecting at least 25% of individuals over 85 years of age) and is associated with substantial cognitive impairment. Risk factors implicated in age-related TDP-43 proteinopathy include commonly inherited gene variants, comorbid Alzheimer's disease pathology, and thyroid hormone dysfunction. To test parameters that are associated with aging-related TDP-43 pathology, we performed exploratory analyses of pathologic, genetic, and biochemical data derived from research volunteers in the University of Kentucky Alzheimer's Disease Center autopsy cohort (n = 136 subjects). Digital pathologic methods were used to discriminate and quantify both neuritic and intracytoplasmic TDP-43 pathology …


Human Body Composition And Immunity: Visceral Adipose Tissue Produces Il-15 And Muscle Strength Inversely Correlates With Nk Cell Function In Elderly Humans, Ahmad Al-Attar, Steven R. Presnell, Jody L. Clasey, Douglas E. Long, R. Grace Walton, Morgan Sexton, Marlene E. Starr, Philip A. Kern, Charlotte A. Peterson, Charles T. Lutz Mar 2018

Human Body Composition And Immunity: Visceral Adipose Tissue Produces Il-15 And Muscle Strength Inversely Correlates With Nk Cell Function In Elderly Humans, Ahmad Al-Attar, Steven R. Presnell, Jody L. Clasey, Douglas E. Long, R. Grace Walton, Morgan Sexton, Marlene E. Starr, Philip A. Kern, Charlotte A. Peterson, Charles T. Lutz

Pathology and Laboratory Medicine Faculty Publications

Natural killer (NK) lymphocyte-mediated cytotoxicity and cytokine secretion control infections and cancers, but these crucial activities decline with age. NK cell development, homeostasis, and function require IL-15 and its chaperone, IL-15 receptor alpha (IL-15Rα). Macrophages and dendritic cells (DC) are major sources of these proteins. We had previously postulated that additional IL-15 and IL-15Rα is made by skeletal muscle and adipose tissue. These sources may be important in aging, when IL-15-producing immune cells decline. NK cells circulate through adipose tissue, where they may be exposed to local IL-15. The objectives of this work were to determine (1) if human muscle, …


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 Oct 2017

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 …


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 Jan 2015

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 …


Hippocampal Sclerosis Of Aging, A Prevalent And High-Morbidity Brain Disease, Peter T. Nelson, Charles D. Smith, Erin L. Abner, Bernard J. Wilfred, Wang-Xia Wang, Janna H. Neltner, Michael Baker, David W. Fardo, Richard J. Kryscio, Stephen W. Scheff, Gregory A. Jicha, Kurt A. Jellinger, Linda J. Van Eldik, Frederick A. Schmitt Aug 2013

Hippocampal Sclerosis Of Aging, A Prevalent And High-Morbidity Brain Disease, Peter T. Nelson, Charles D. Smith, Erin L. Abner, Bernard J. Wilfred, Wang-Xia Wang, Janna H. Neltner, Michael Baker, David W. Fardo, Richard J. Kryscio, Stephen W. Scheff, Gregory A. Jicha, Kurt A. Jellinger, Linda J. Van Eldik, Frederick A. Schmitt

Sanders-Brown Center on Aging Faculty Publications

Hippocampal sclerosis of aging (HS-Aging) is a causative factor in a large proportion of elderly dementia cases. The current definition of HS-Aging rests on pathologic criteria: neuronal loss and gliosis in the hippocampal formation that is out of proportion to AD-type pathology. HS-Aging is also strongly associated with TDP-43 pathology. HS-Aging pathology appears to be most prevalent in the oldest-old: autopsy series indicate that 5-30 % of nonagenarians have HS-Aging pathology. Among prior studies, differences in study design have contributed to the study-to-study variability in reported disease prevalence. The presence of HS-Aging pathology correlates with significant cognitive impairment which is …


Sarcopenia, Obesity, And Natural Killer Cell Immune Senescence In Aging: Altered Cytokine Levels As A Common Mechanism, Charles T. Lutz, Lebris S. Quinn Aug 2012

Sarcopenia, Obesity, And Natural Killer Cell Immune Senescence In Aging: Altered Cytokine Levels As A Common Mechanism, Charles T. Lutz, Lebris S. Quinn

Pathology and Laboratory Medicine Faculty Publications

Human aging is characterized by both physical and physiological frailty. A key feature of frailty, sarcopenia is the age-associated decline in skeletal muscle mass, strength, and endurance that characterize even the healthy elderly. Increases in adiposity, particularly in visceral adipose tissue, are almost universal in aging individuals and can contribute to sarcopenia and insulin resistance by increasing levels of inflammatory cytokines known collectively as adipokines. Aging also is associated with declines in adaptive and innate immunity, known as immune senescence, which are risk factors for cancer and all-cause mortality. The cytokine interleukin-15 (IL-15) is highly expressed in skeletal muscle tissue …


Micrornas (Mirnas) In Neurodegenerative Diseases, Peter T. Nelson, Wang-Xia Wang, Bernard W. Rajeev Jan 2008

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 …