Medicine and Health Sciences Commons^™

Rapamycin Rescues Vascular, Metabolic And Learning Deficits In Apolipoprotein E4 Transgenic Mice With Pre-Symptomatic Alzheimer’S Disease, Ai-Ling Lin, Jordan B. Jahrling, Wei Zhang, Nicholas Derosa, Vikas Bakshi, Peter Romero, Veronica Galvan, Arlan Richardson

Sanders-Brown Center on Aging Faculty Publications

Apolipoprotein E ɛ4 allele is a common susceptibility gene for late-onset Alzheimer's disease. Brain vascular and metabolic deficits can occur in cognitively normal apolipoprotein E ɛ4 carriers decades before the onset of Alzheimer's disease. The goal of this study was to determine whether early intervention using rapamycin could restore neurovascular and neurometabolic functions, and thus impede pathological progression of Alzheimer's disease-like symptoms in pre-symptomatic Apolipoprotein E ɛ4 transgenic mice. Using in vivo, multimodal neuroimaging, we found that apolipoprotein E ɛ4 mice treated with rapamycin had restored cerebral blood flow, blood–brain barrier integrity and glucose metabolism, compared …

Mice Deficient In Endothelial Α5 Integrin Are Profoundly Resistant To Experimental Ischemic Stroke, Jill Roberts, Leon De Hoog, Gregory J. Bix

Sanders-Brown Center on Aging Faculty Publications

Stroke is a disease in dire need of better therapies. We have previously shown that a fragment of the extracellular matrix proteoglycan, perlecan, has beneficial effects following cerebral ischemia via the α5β1 integrin receptor. We now report that endothelial cell selective α5 integrin deficient mice (α5 KO) are profoundly resistant to ischemic infarct after transient middle cerebral artery occlusion. Specifically, α5 KOs had little to no infarct 2–3 days post-stroke, whereas controls had an increase in mean infarct volume over the same time period as expected. Functional outcome is also improved in the α5 KOs compared with controls. Importantly, no …

Early Shifts Of Brain Metabolism By Caloric Restriction Preserve White Matter Integrity And Long-Term Memory In Aging Mice, Janet Guo, Vikas Bakshi, Ai-Ling Lin

Sanders-Brown Center on Aging Faculty Publications

Preservation of brain integrity with age is highly associated with lifespan determination. Caloric restriction (CR) has been shown to increase longevity and healthspan in various species; however, its effects on preserving living brain functions in aging remain largely unexplored. In the study, we used multimodal, non-invasive neuroimaging (PET/MRI/MRS) to determine in vivo brain glucose metabolism, energy metabolites, and white matter structural integrity in young and old mice fed with either control or 40% CR diet. In addition, we determined the animals’ memory and learning ability with behavioral assessments. Blood glucose, blood ketone bodies, and body weight were also measured. We …

Abcc9/Sur2 In The Brain: Implications For Hippocampal Sclerosis Of Aging And A Potential Therapeutic Target, Peter T. Nelson, Gregory A. Jicha, Wang-Xia Wang, Eseosa T. Ighodaro, Sergey C. Artiushin, Colin G. Nichols, David W. Fardo

Sanders-Brown Center on Aging Faculty Publications

The ABCC9 gene and its polypeptide product, SUR2, are increasingly implicated in human neurologic disease, including prevalent diseases of the aged brain. SUR2 proteins are a component of the ATP-sensitive potassium (“K _ATP ”) channel, a metabolic sensor for stress and/or hypoxia that has been shown to change in aging. The K _ATP channel also helps regulate the neurovascular unit. Most brain cell types express SUR2, including neurons, astrocytes, oligodendrocytes, microglia, vascular smooth muscle, pericytes, and endothelial cells. Thus it is not surprising that ABCC9 gene variants are associated with risk for human brain diseases. For example, Cantu syndrome is …

Time-Dependent Effects Of Cx3cr1 In A Mouse Model Of Mild Traumatic Brain Injury, Heidi Y. Febinger, Hannah E. Thomasy, Maria N. Pavlova, Kristyn M. Ringgold, Paulien R. Barf, Amrita M. George, Jenna N. Grillo, Adam D. Bachstetter, Jenny A. Garcia, Astrid E. Cardona, Mark R. Opp, Carmelina Gemma

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Neuroinflammation is an important secondary mechanism that is a key mediator of the long-term consequences of neuronal injury that occur in traumatic brain injury (TBI). Microglia are highly plastic cells with dual roles in neuronal injury and recovery. Recent studies suggest that the chemokine fractalkine (CX3CL1, FKN) mediates neural/microglial interactions via its sole receptor CX3CR1. CX3CL1/CX3CR1 signaling modulates microglia activation, and depending upon the type and time of injury, either protects or exacerbates neurological diseases.

METHODS: In this study, mice deficient in CX3CR1 were subjected to mild controlled cortical impact injury (CCI), a model of TBI. We evaluated …

Muscle Weakness During Aging: A Deficiency State Involving Declining Angiogenesis, Charles T. Ambrose

Microbiology, Immunology, and Molecular Genetics Faculty Publications

This essay begins by proposing that muscle weakness of old age from sarcopenia is due in large part to reduced capillary density in the muscles, as documented in 9 reports of aged persons and animals. Capillary density (CD) is determined by local levels of various angiogenic factors, which also decline in muscles with aging, as reported in 7 studies of old persons and animals. There are also numerous reports of reduced CD in the aged brain and other studies showing reduced CD in the kidney and heart of aged animals. Thus a waning angiogenesis throughout the body may be …

Novel Human Abcc9/Sur2 Brain-Expressed Transcripts And An Eqtl Relevant To Hippocampal Sclerosis Of Aging, Peter T. Nelson, Wang-Xia Wang, Bernard R. Wilfred, Angela Wei, James Dimayuga, Qingwei Huang, Eseosa T. Ighodaro, Sergey C. Artiushin, David W. Fardo

Sanders-Brown Center on Aging Faculty Publications

ABCC9 genetic polymorphisms are associated with increased risk for various human diseases including hippocampal sclerosis of aging. The main goals of this study were 1 > to detect the ABCC9 variants and define the specific 3′ untranslated region (3′UTR) for each variant in human brain, and 2 > to determine whether a polymorphism (rs704180) associated with risk for hippocampal sclerosis of aging pathology is also associated with variation in ABCC9 transcript expression and/or splicing. Rapid amplification of ABCC9 cDNA ends (3′RACE) provided evidence of novel 3′ UTR portions of ABCC9 in human brain. In silico and experimental studies were performed focusing on …

Albumin Administration In Acute Ischemic Stroke: Safety Analysis Of The Alias Part 2 Multicenter Trial, Michael D. Hill, Renee H. Martin, Yuko Y. Palesch, Claudias S. Moy, Diego Tamariz, Karla J. Ryckborst, Elizabeth B. Jones, David Weisman, L. Creed Pettigrew, Myron D. Ginsberg

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Albumin treatment of ischemic stroke was associated with cardiopulmonary adverse events in previous studies and a low incidence of intracranial hemorrhage. We sought to describe the neurological and cardiopulmonary adverse events in the ALIAS Part 2 Multicenter Trial.

METHODS: Ischemic stroke patients, aged 18-83 and a baseline NIHSS ≥ 6, were randomized to treatment with ALB or saline control within 5 hours of stroke onset. Neurological adverse events included symptomatic intracranial hemorrhage, hemicraniectomy, neurological deterioration and neurological death. Cardiopulmonary adverse events included pulmonary edema/congestive heart failure, acute coronary syndromes, atrial fibrillation, pneumonia and pulmonary thromboembolism.

RESULTS: …

Insights Into Alzheimer’S Disease: The Levels Of Signaling Proteins In Brain Of Control Subjects Versus Brain From Subjects With Mild Cognitive Impairment, Georgianne F. Tiu

Kaleidoscope

The purpose of this study was to measure the expression levels of key signaling proteins in brain tissue from subjects with mild cognitive impairment (MCI) compared to control subjects. MCI is considered to be the beginning phase of Alzheimer’s disease (AD). Tumor necrosis factor alpha (TNF-α), nuclear factor kappa beta (NF-κβ), phospho Bad (pBad), and ubiquitin C-terminal hydrolase-L1 (UCH-L1) are four of the proteins that were investigated. Trends of either decreases or increases in protein expression levels in MCI vs. control brain were investigated. Western blot analysis was used in order to identify these trends. These signaling protein levels are …

Reversal Of Aging-Related Neuronal Ca2+ Dysregulation And Cognitive Impairment By Delivery Of A Transgene Encoding Fk506-Binding Protein 12.6/1b To The Hippocampus, John C. Gant, Kuey-Chu Chen, Inga Kadish, Eric M. Blalock, Olivier Thibault, Nada M. Porter, Philip W. Landfield

Pharmacology and Nutritional Sciences Faculty Publications

Brain Ca(2+) regulatory processes are altered during aging, disrupting neuronal, and cognitive functions. In hippocampal pyramidal neurons, the Ca(2+)-dependent slow afterhyperpolarization (sAHP) exhibits an increase with aging, which correlates with memory impairment. The increased sAHP results from elevated L-type Ca(2+) channel activity and ryanodine receptor (RyR)-mediated Ca(2+) release, but underlying molecular mechanisms are poorly understood. Previously, we found that expression of the gene encoding FK506-binding protein 12.6/1b (FKBP1b), a small immunophilin that stabilizes RyR-mediated Ca(2+) release in cardiomyocytes, declines in hippocampus of aged rats and Alzheimer's disease subjects. Additionally, knockdown/disruption of hippocampal FKBP1b in young rats augments neuronal Ca(2+) responses. …

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 …

Role Of Mitochondria In Regulating Microrna Activity And Its Relevance To The Central Nervous System, Wang-Xia Wang, Joe E. Springer

Physical Medicine and Rehabilitation Faculty Publications

No abstract provided.

Low Neural Exosomal Levels Of Cellular Survival Factors In Alzheimer's Disease, Edward J. Goetzl, Adam Boxer, Janice B. Schwartz, Erin Abner, Ronald C. Petersen, Bruce L. Miller, Olga D. Carlson, Maja Mustapic, Dimitrios Kapogiannis

Sanders-Brown Center on Aging Faculty Publications

Transcription factors that mediate neuronal defenses against diverse stresses were quantified in plasma neural-derived exosomes of Alzheimer's disease or frontotemporal dementia patients and matched controls. Exosomal levels of low-density lipoprotein receptor-related protein 6, heat-shock factor-1, and repressor element 1-silencing transcription factor all were significantly lower in Alzheimer's disease patients than controls (P < 0.0001). In frontotemporal dementia, the only significant difference was higher levels of repressor element 1-silencing transcription factor than in controls. Exosomal transcription factors were diminished 2-10 years before clinical diagnosis of Alzheimer's disease. Low exosomal levels of survival proteins may explain decreased neuronal resistance to Alzheimer's disease neurotoxic proteins.

Apoε2 And Education In Cognitively Normal Older Subjects With High Levels Of Ad Pathology At Autopsy: Findings From The Nun Study, Diego Iacono, Peter Zandi, Myron Gross, William R. Markesbery, Olga Pletnikova, Gay Rudow, Juan C. Troncoso

Sanders-Brown Center on Aging Faculty Publications

Asymptomatic Alzheimer's disease (ASYMAD) subjects are individuals characterized by preserved cognition before death despite substantial AD pathology at autopsy. ASYMAD subjects show comparable levels of AD pathology, i.e. β-amyloid neuritic plaques (Aβ-NP) and tau-neurofibrillary tangles (NFT), to those observed in mild cognitive impairment (MCI) and some definite AD cases. Previous clinicopathologic studies on ASYMAD subjects have shown specific phenomena of hypertrophy in the cell bodies, nuclei, and nucleoli of hippocampal pyramidal neurons and other cerebral areas. Since it is well established that the allele APOε4 is a major genetic risk factor for AD, we examined whether specific alleles of APOE …

Calcium Channel Blockers, Progression To Dementia, And Effects On Amyloid Beta Peptide Production, Mark A. Lovell, Erin Abner, Richard Kryscio, Liou Xu, Shuling X. Fister, Bert C. Lynn

Sanders-Brown Center on Aging Faculty Publications

Previous epidemiologic studies suggest that antihypertensive drugs may be protective against cognitive decline. To determine if subjects enrolled in the University of Kentucky longitudinal aging study who used antihypertensive drugs showed diminished progression to dementia, we used a 3-parameter logistic regression model to compare the rate of progression to dementia for subjects who used any of the five common categories of antihypertensive drugs to those with similar demographic characteristics but who did not use antihypertensives. Regression modeling showed that subjects who used calcium channel blockers (CCBs) but not the other classes of antihypertensives showed a significant decrease in the rate …

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 …

Attenuation Of Traumatic Brain Injury-Induced Cognitive Impairment In Mice By Targeting Increased Cytokine Levels With A Small Molecule Experimental Therapeutic, Adam D. Bachstetter, Scott J. Webster, Danielle S. Goulding, Jonathan E. Morton, D. Martin Watterson, Linda J. Van Eldik

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Evidence from clinical studies and preclinical animal models suggests that proinflammatory cytokine overproduction is a potential driving force for pathology progression in traumatic brain injury (TBI). This raises the possibility that selective targeting of the overactive cytokine response, a component of the neuroinflammation that contributes to neuronal dysfunction, may be a useful therapeutic approach. MW151 is a CNS-penetrant, small molecule experimental therapeutic that selectively restores injury- or disease-induced overproduction of proinflammatory cytokines towards homeostasis. We previously reported that MW151 administered post-injury (p.i.) is efficacious in a closed head injury (CHI) model of diffuse TBI in mice. Here we test …

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

Sanders-Brown Center on Aging Faculty Publications

No abstract provided.

A Practical Algorithm For Managing Alzheimer's Disease: What, When, And Why?, Jeffrey L. Cummings, Richard S. Isaacson, Frederick A. Schmitt, Drew M. Velting

Sanders-Brown Center on Aging Faculty Publications

Alzheimer's disease (AD) is the most common form of dementia and its prevalence is increasing. Recent developments in AD management provide improved ways of supporting patients and their caregivers throughout the disease continuum. Managing cardiovascular risk factors, maintaining an active lifestyle (with regular physical, mental and social activity) and following a Mediterranean diet appear to reduce AD risk and may slow cognitive decline. Pharmacologic therapy for AD should be initiated upon diagnosis. All of the currently available cholinesterase inhibitors (ChEIs; donepezil, galantamine, and rivastigmine) are indicated for mild-to-moderate AD. Donepezil (10 and 23 mg/day) and rivastigmine transdermal patch (13.3 mg/24 …

Mitochondria-Associated Micrornas In Rat Hippocampus Following Traumatic Brain Injury, Wang-Xia Wang, Nishant P. Visavadiya, Jignesh D. Pandya, Peter T. Nelson, Patrick G. Sullivan, Joe E. Springer

Sanders-Brown Center on Aging Faculty Publications

Traumatic brain injury (TBI) is a major cause of death and disability. However, the molecular events contributing to the pathogenesis are not well understood. Mitochondria serve as the powerhouse of cells, respond to cellular demands and stressors, and play an essential role in cell signaling, differentiation, and survival. There is clear evidence of compromised mitochondrial function following TBI; however, the underlying mechanisms and consequences are not clear. MicroRNAs (miRNAs) are small non-coding RNA molecules that regulate gene expression post-transcriptionally, and function as important mediators of neuronal development, synaptic plasticity, and neurodegeneration. Several miRNAs show altered expression following TBI; however, the …

A Therapeutic Approach For Senile Dementias: Neuroangiogenesis, Charles T. Ambrose

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Alzheimer's disease (AD) and related senile dementias (SDs) represent a growing medical and economic crisis in this country. Apart from cautioning persons about risk factors, no practical, effective therapy is currently available. Much of the recent research in AD has been based on the amyloid cascade theory. Another approach assumes a vascular basis for SDs. This paper presents evidence from a score of studies that cerebral capillary density (CCD) declines during old age in animals and people as well as in AD. Neuroangiogenic (NAG) factors initiate and maintain capillaries in the brain. Thus a waning level of these factors and …

Polypharmacy Practice Inquiry Project, Mary T. Skinner

DNP Projects

“The impending crisis, which has been foreseen for decades, is now upon us.The nation needs to act now to prepare the health care workforce to meet the care needs of older adults.” Institute of Medicine.

Given the rising tide of people over the age of 65, taking multiple medications or polypharmacy is a becoming more prevalent in older adults. Unfortunately, there are many negative consequences associated with polypharmacy. Specifically, this burden has been associated with greater health care costs and an increased risk of adverse drug events, drug-interactions, medication non-adherence, reduced functional capacity and multiple geriatric syndromes including cognitive impairment. …

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 …

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 …