Medicine and Health Sciences Commons^™

Post-Acquisition Processing Confounds In Brain Volumetric Quantification Of White Matter Hyperintensities, Ahmed A. Bahrani, Omar M. Al-Janabi, Erin L. Abner, Shoshana H. Bardach, Richard J. Kryscio, Donna M. Wilcock, Charles D. Smith, Gregory A. Jicha

Neurology Faculty Publications

BACKGROUND: Disparate research sites using identical or near-identical magnetic resonance imaging (MRI) acquisition techniques often produce results that demonstrate significant variability regarding volumetric quantification of white matter hyperintensities (WMH) in the aging population. The sources of such variability have not previously been fully explored.

NEW METHOD: 3D FLAIR sequences from a group of randomly selected aged subjects were analyzed to identify sources-of-variability in post-acquisition processing that can be problematic when comparing WMH volumetric data across disparate sites. The methods developed focused on standardizing post-acquisition protocol processing methods to develop a protocol with less than 0.5% inter-rater variance.

RESULTS: A series …

Co-Prescription Network Reveals Social Dynamics Of Opioid Doctor Shopping, Brea L. Perry, Kai Cheng Yang, Patrick Kaminski, Meltem Odabas, Jaehyuk Park, Michelle M. Martel, Carrie B. Oser, Patricia R. Freeman, Yong-Yeol Ahn, Jeffery C. Talbert

Psychology Faculty Publications

This paper examines network prominence in a co-prescription network as an indicator of opioid doctor shopping (i.e., fraudulent solicitation of opioids from multiple prescribers). Using longitudinal data from a large commercially insured population, we construct a network where a tie between patients is weighted by the number of shared opioid prescribers. Given prior research suggesting that doctor shopping may be a social process, we hypothesize that active doctor shoppers will occupy central structural positions in this network. We show that network prominence, operationalized using PageRank, is associated with more opioid prescriptions, higher predicted risk for dangerous morphine dosage, opioid overdose, …

Neural Mechanisms Of The Rejection-Aggression Link, David S. Chester, Donald R. Lynam, Richard Milich, C. Nathan Dewall

Psychology Faculty Publications

Social rejection is a painful event that often increases aggression. However, the neural mechanisms of this rejection–aggression link remain unclear. A potential clue may be that rejected people often recruit the ventrolateral prefrontal cortex’s (VLPFC) self-regulatory processes to manage the pain of rejection. Using functional MRI, we replicated previous links between rejection and activity in the brain’s mentalizing network, social pain network and VLPFC. VLPFC recruitment during rejection was associated with greater activity in the brain’s reward network (i.e. the ventral striatum) when individuals were given an opportunity to retaliate. This retaliation-related striatal response was associated with greater levels of …

Pathway Of Protection: Ethnic Identity, Self-Esteem, And Substance Use Among Multiracial Youth, Sycarah Fisher, Tamika C. B. Zapolski, Chelsea Sheehan, Jessica Barnes-Najor

Educational, School, and Counseling Psychology Faculty Publications

Fifty percent of adolescents have tried an illicit drug and 70% have tried alcohol by the end of high school, with even higher rates among multiracial youth. Ethnic identity is a protective factor against substance use for minority groups. However, little is known about the mechanisms that facilitate its protective effects, and even less is known about this relationship for multiracial youth. The purpose of the present study was to examine the protective effect of ethnic identity on substance use and to determine whether this relationship operated indirectly through self-esteem, a strong predictor of substance use for among adolescent populations. …

Examining The Protective Effect Of Ethnic Identity On Drug Attitudes And Use Among A Diverse Youth Population, Tamika C. B. Zapolski, Sycarah Fisher, Devin E. Banks, Devon J. Hensel, Jessica Barnes-Najor

Educational, School, and Counseling Psychology Faculty Publications

Ethnic identity is an important buffer against drug use among minority youth. However, limited work has examined pathways through which ethnic identity mitigates risk. School-aged youth (N = 34,708; 52 % female) of diverse backgrounds (i.e., African American (n = 5333), Asian (n = 392), Hispanic (n = 662), Multiracial (n = 2129), Native American (n = 474), and White (n = 25718) in grades 4–12 provided data on ethnic identity, drug attitudes, and drug use. After controlling for gender and grade, higher ethnic identity was associated with lower past month drug use …

Using Neonatal Skin To Study The Developmental Programming Of Aging, Leryn J. Reynolds, Brett J. Dickens, Benjamin B. Green, Carmen J. Marsit, Kevin J. Pearson

Pharmacology and Nutritional Sciences Faculty Publications

Numerous studies have examined how both negative and positive maternal exposures (environmental contaminants, nutrition, exercise, etc.) impact offspring risk for age-associated diseases such as obesity, type 2 diabetes, hypertension, and others. The purpose of this study was to introduce the foreskin as a novel model to examine developmental programming in human neonates, particularly in regard to adipogenesis and insulin receptor signaling, major contributors to age-associated diseases such as obesity and diabetes. Neonatal foreskin was collected following circumcision and primary dermal fibroblasts were isolated to perform adipocyte differentiation and insulin stimulation experiments. Human neonatal foreskin primary fibroblasts take up lipid when …

Impact Of Home Visit Capacity On Genetic Association Studies Of Late-Onset Alzheimer's Disease, David W. Fardo, Laura E. Gibbons, Shubhabrata Mukherjee, M. Maria Glymour, Wayne Mccormick, Susan M. Mccurry, James D. Bowen, Eric B. Larson, Paul K. Crane

Biostatistics Faculty Publications

INTRODUCTION—Findings for genetic correlates of late-onset Alzheimer's disease (LOAD) in studies that rely solely on clinic visits may differ from those with capacity to follow participants unable to attend clinic visits.

METHODS—We evaluated previously identified LOAD-risk single nucleotide variants in the prospective Adult Changes in Thought study, comparing hazard ratios (HRs) estimated using the full data set of both in-home and clinic visits (n = 1697) to HRs estimated using only data that were obtained from clinic visits (n = 1308). Models were adjusted for age, sex, principal components to account for ancestry, and additional health indicators.

RESULTS …

Csf Protein Changes Associated With Hippocampal Sclerosis Risk Gene Variants Highlight Impact Of Grn/Pgrn, David W. Fardo, Yuriko Katsumata, John S. K. Kauwe, Yuetiva Deming, Oscar Harari, Carlos Cruchaga, Alzheimer’S Disease Neuroimaging Initiative, Peter T. Nelson

Sanders-Brown Center on Aging Faculty Publications

Objective—Hippocampal sclerosis of aging (HS-Aging) is a common cause of dementia in older adults. We tested the variability in cerebrospinal fluid (CSF) proteins associated with previously identified HS-Aging risk single nucleotide polymorphisms (SNPs).

Methods—Alzheimer’s Disease Neuroimaging Initiative cohort (ADNI; n=237) data, combining both multiplexed proteomics CSF and genotype data, were used to assess the association between CSF analytes and risk SNPs in four genes (SNPs): GRN (rs5848), TMEM106B (rs1990622), ABCC9 (rs704180), and KCNMB2 (rs9637454). For controls, non-HS-Aging SNPs in APOE (rs429358/rs7412) and MAPT (rs8070723) were also analyzed against Aβ1-42 and total tau CSF analytes.

Results—The GRN risk …

Partner Influence In Diet And Exercise Behaviors: Testing Behavior Modeling, Social Control, And Normative Body Size, Brea Perry, Gabriele Ciciurkaite, Christy Freadreacea Brady, Justin Garcia

Sociology Faculty Publications

Previous research has documented social contagion in obesity and related health behaviors, but less is known about the social processes underlying these patterns. Focusing on married or cohabitating couples, we simultaneously explore three potential social mechanisms influencing obesity: normative body size, social control, and behavior modeling. We analyze the association between partner characteristics and the obesity-related health behaviors of focal respondents, comparing the effects of partners’ body type, partners’ attempts to manage respondents’ eating behaviors, and partners’ own health behaviors on respondents’ health behaviors (physical activity, fruit and vegetable consumption, and fast food consumption). Data on 215 partners are extracted …

Dna Methylation Signatures Of Chronic Low-Grade Inflammation Are Associated With Complex Diseases, Symen Ligthart, Carola Marzi, Stella Aslibekyan, Michael M. Mendelson, Karen N. Conneely, Toshiko Tanaka, Elena Colicino, Lindsay L. Waite, Roby Joehanes, Weihua Guan, Jennifer A. Brody, Cathy Elks, Riccardo Marioni, Min A. Jhun, Golareh Agha, Jan Bressler, Cavin K. Ward-Caviness, Brian H. Chen, Tianxiao Huan, Kelly Bakulski, Elias L. Salfati, Whi-Empc Investigators, Giovanni Fiorito, Charge Epigenetics Of Coronary Heart Disease, Simone Wahl, Katharina Schramm, Jin Sha, Dena G. Hernandez, Allan C. Just, Jennifer A. Smith, Donna K. Arnett

Epidemiology and Environmental Health Faculty Publications

Background: Chronic low-grade inflammation reflects a subclinical immune response implicated in the pathogenesis of complex diseases. Identifying genetic loci where DNA methylation is associated with chronic low-grade inflammation may reveal novel pathways or therapeutic targets for inflammation.

Results: We performed a meta-analysis of epigenome-wide association studies (EWAS) of serum C-reactive protein (CRP), which is a sensitive marker of low-grade inflammation, in a large European population (n = 8863) and trans-ethnic replication in African Americans (n = 4111). We found differential methylation at 218 CpG sites to be associated with CRP (P < 1.15 × 10^–7) in the discovery panel …

Accuracy Of Name And Age Data Provided About Network Members In A Social Network Study Of People Who Use Drugs: Implications For Constructing Sociometric Networks, April M. Young, Abby E. Rudolph, Amanda E. Su, Lee King, Susan Jent, Jennifer R. Havens

Epidemiology and Environmental Health Faculty Publications

Purpose—Network analysis has become increasingly popular in epidemiologic research, but the accuracy of data key to constructing risk networks is largely unknown. Using network data from people who use drugs (PWUD), the study examined how accurately PWUD reported their network members’ (i.e., alters’) names and ages.

Methods—Data were collected from 2008 to 2010 from 503 PWUD residing in rural Appalachia. Network ties (n=897) involved recent (past 6 months) sex, drug co-usage, and/or social support. Participants provided alters’ names, ages, and relationship-level characteristics; these data were cross-referenced to that of other participants to identify participant-participant relationships and to determine …

Reduced Efficacy Of Anti-AΒ Immunotherapy In A Mouse Model Of Amyloid Deposition And Vascular Cognitive Impairment Comorbidity, Erica M. Weekman, Tiffany L. Sudduth, Carly N. Caverly, Timothy J. Kopper, Oliver W. Phillips, David K. Powell, Donna M. Wilcock

Sanders-Brown Center on Aging Faculty Publications

Vascular cognitive impairment and dementia (VCID) is the second most common form of dementia behind Alzheimer's disease (AD). It is estimated that 40% of AD patients also have some form of VCID. One promising therapeutic for AD is anti-Aβ immunotherapy, which uses antibodies against Aβ to clear it from the brain. While successful in clearing Aβ and improving cognition in mice, anti-Aβ immunotherapy failed to reach primary cognitive outcomes in several different clinical trials. We hypothesized that one potential reason the anti-Aβ immunotherapy clinical trials were unsuccessful was due to this high percentage of VCID …

Similarities And Differences In Sexual Risk Behaviors Between Young Black Msm Who Do And Do Not Have Sex With Females, Richard A. Crosby, Leandro Mena, Angelica Geter, Demarc Hickson

Health, Behavior & Society Faculty Publications

The objective of this study is to determine whether young Black MSM who also have sex with females report similar levels of sexual risk behaviors as those not having sex with females. YBMSM (N = 400) were recruited from an STI clinic, located in the Southern U.S. Men completed an audio-computer assisted self-interview and donated specimens for STI/HIV testing. Forty-three percent recently engaged in penile-vaginal sex. They were less likely to report having concurrent partners (P = .01), unprotected fellatio (P = .04), multiple partners as a bottom (P < .02), any unprotected anal sex as a bottom (P < .013), and any anal sex (P = .007). They were equally likely …

Colorectal Cancer Prevention: Perspectives Of Key Players From Social Networks In A Low-Income Rural Us Region, Nancy E. Schoenberg, Kathryn Eddens, Adam Jonas, Claire Snell-Rood, Christina R. Studts, Benjamin Broder-Oldach, Mira L. Katz

Behavioral Science Faculty Publications

Social networks influence health behavior and health status. Within social networks, “key players” often influence those around them, particularly in traditionally underserved areas like the Appalachian region in the USA. From a total sample of 787 Appalachian residents, we identified and interviewed 10 key players in complex networks, asking them what comprises a key player, their role in their network and community, and ideas to overcome and increase colorectal cancer (CRC) screening. Key players emphasized their communication skills, resourcefulness, and special occupational and educational status in the community. Barriers to CRC screening included negative perceptions of the colonoscopy screening procedure, …

Mw151 Inhibited Il-1Β Levels After Traumatic Brain Injury With No Effect On Microglia Physiological Responses, Adam D. Bachstetter, Zhengqiu Zhou, Rachel K. Rowe, Bin Xing, Danielle S. Goulding, Alyssa N. Conley, Pradoldej Sompol, Shelby Meier, Jose F. Abisambra, Jonathan Lifshitz, D. Martin Watterson, Linda J. Van Eldik

Sanders-Brown Center on Aging Faculty Publications

A prevailing neuroinflammation hypothesis is that increased production of proinflammatory cytokines contributes to progressive neuropathology, secondary to the primary damage caused by a traumatic brain injury (TBI). In support of the hypothesis, post-injury interventions that inhibit the proinflammatory cytokine surge can attenuate the progressive pathology. However, other post-injury neuroinflammatory responses are key to endogenous recovery responses. Therefore, it is critical that pharmacological attenuation of detrimental or dysregulated neuroinflammatory processes avoid pan-suppression of inflammation. MW151 is a CNS-penetrant, small molecule experimental therapeutic that restores injury- or disease-induced overproduction of proinflammatory cytokines towards homeostasis without immunosuppression. Post-injury administration of MW151 in a …

AΒ40 Reduces P-Glycoprotein At The Blood-Brain Barrier Through The Ubiquitin-Proteasome Pathway, Anika M. S. Hartz, Yu Zhong, Andrea Wolf, Harry Levine Iii, David S. Miller, Björn Bauer

Sanders-Brown Center on Aging Faculty Publications

Failure to clear amyloid-β (Aβ) from the brain is in part responsible for Aβ brain accumulation in Alzheimer's disease (AD). A critical protein for clearing Aβ across the blood–brain barrier is the efflux transporter P-glycoprotein (P-gp) in the luminal plasma membrane of the brain capillary endothelium. P-gp is reduced at the blood–brain barrier in AD, which has been shown to be associated with Aβ brain accumulation. However, the mechanism responsible for P-gp reduction in AD is not well understood. Here we focused on identifying critical mechanistic steps involved in reducing P-gp in AD. We …

Altered Lysosomal Proteins In Neural-Derived Plasma Exosomes In Preclinical Alzheimer Disease, Edward J. Goetzl, Adam Boxer, Janice B. Schwartz, Erin L. Abner, Ronald C. Petersen, Bruce L. Miller, Dimitrios Kapogiannis

Sanders-Brown Center on Aging Faculty Publications

OBJECTIVE: Diverse autolysosomal proteins were quantified in neurally derived blood exosomes from patients with Alzheimer disease (AD) and controls to investigate disordered neuronal autophagy.

METHODS: Blood exosomes obtained once from patients with AD (n = 26) or frontotemporal dementia (n = 16), other patients with AD (n = 20) both when cognitively normal and 1 to 10 years later when diagnosed, and case controls were enriched for neural sources by anti-human L1CAM antibody immunoabsorption. Extracted exosomal proteins were quantified by ELISAs and normalized with the CD81 exosomal marker.

RESULTS: Mean exosomal levels of cathepsin D, lysosome-associated membrane …

Closed Head Injury In An Age-Related Alzheimer Mouse Model Leads To An Altered Neuroinflammatory Response And Persistent Cognitive Impairment, Scott J. Webster, Linda J. Van Eldik, D. Martin Watterson, Adam D. Bachstetter

Sanders-Brown Center on Aging Faculty Publications

Epidemiological studies have associated increased risk of Alzheimer's disease (AD)-related clinical symptoms with a medical history of head injury. Currently, little is known about pathophysiology mechanisms linked to this association. Persistent neuroinflammation is one outcome observed in patients after a single head injury. Neuroinflammation is also present early in relevant brain regions during AD pathology progression. In addition, previous mechanistic studies in animal models link neuroinflammation as a contributor to neuropathology and cognitive impairment in traumatic brain injury (TBI) or AD-related models. Therefore, we explored the potential interplay of neuroinflammatory responses in TBI and AD by analysis of the temporal …

Unlocking The Mysteries Of Tdp-43, Keith A. Josephs, Peter T. Nelson

Sanders-Brown Center on Aging Faculty Publications

No abstract provided.

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 …

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 …

Chess Improves Cancer Caregivers' Burden And Mood: Results Of An Ehealth Rct, Lori L. Dubenske, David H. Gustafson, Kang Namkoong, Robert P. Hawkins, Amy K. Atwood, Roger L. Brown, Ming-Yuan Chih, Fiona Mctavish, Cindy L. Carmack, Mary K. Buss, Ramaswamy Govindan, James F. Cleary

Community & Leadership Development Faculty Publications

OBJECTIVE: Informal caregivers (family and friends) of people with cancer are often unprepared for their caregiving role, leading to increased burden or distress. Comprehensive Health Enhancement Support System (CHESS) is a Web-based lung cancer information, communication, and coaching system for caregivers. This randomized trial reports the impact on caregiver burden, disruptiveness, and mood of providing caregivers access to CHESS versus the Internet with a list of recommended lung cancer websites.

METHODS: A total of 285 informal caregivers of patients with advanced nonsmall cell lung cancer were randomly assigned to a comparison group that received Internet or a treatment group that …

Diabetes And Prostate Cancer Screening In Black And White Men, Maureen Sanderson, Jay H. Fowke, Loren Lipworth, Xijing Han, Flora Ukoli, Ann L. Coker, William J. Blot, Margaret K. Hargreaves

CRVAW Faculty Journal Articles

PURPOSE: Prior studies conducted primarily among white men find a reduced risk of prostate cancer associated with time since developing diabetes. While biologic explanations are plausible, the association may in part arise from more frequent prostate cancer screening among those with a diabetes diagnosis. The purpose of the present study was to investigate the association between diabetes and prostate cancer screening.

METHODS: We examined differences in prostate cancer screening (prostate-specific antigen and/or digital rectal examination) testing practices after a diabetes diagnosis among lower-income persons living in the southeastern United States and enrolled in the Southern Community Cohort Study between 2002 …

Intracranial Injection Of Gammagard, A Human Ivig, Modulates The Inflammatory Response Of The Brain And Lowers AΒ In App/Ps1 Mice Along A Different Time Course Than Anti-AΒ Antibodies, Tiffany L. Sudduth, Abigail Greenstein, Donna M. Wilcock

Sanders-Brown Center on Aging Faculty Publications

Gammagard IVIg is a therapeutic approach to treat Alzheimer's disease currently in phase 3 clinical trials. Despite the reported efficacy of the approach the mechanism of action is poorly understood. We have previously shown that intracranial injection of anti-Aβ antibodies into the frontal cortex and hippocampus reveals important information regarding the time course of events once the agent is in the brain. In the current study we compared IVIg, mouse-pooled IgG, and the anti-Aβ antibody 6E10 injected intracranially into the frontal cortex and hippocampus of 7-month-old APP/PS1 mice. We established a time course of events ranging from 1 …

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 …

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 …

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 …

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 …

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 …