Molecular and Cellular Neuroscience Commons^™

High Volume Multiplex Staining Of Mouse Model In Alzheimer’S Associated Disease Pathology, Chloe Embry

Lewis Honors College Thesis Collection

Although neurodegenerative diseases are often clinically distinct, they typically share common pathological markers. One of the most common causes of clinical dementia is Alzheimer’s disease (AD). Pathologically, AD is defined by the presence of intercellular tangles composed of hyperphosphorylated tau proteins and extracellular plaques made of abnormally cleaved amyloid-beta proteins. However recent genome-wide association studies have also found that many of the predispositions for AD are located on or near genes highly expressed in microglia. In the healthy CNS, microglia act as the brain’s immune system and are chiefly involved in neuronal support and maintaining homeostasis throughout the CNS. Typically, …

Il-1r1 Within The Meningeal Lymphatic System, Nolan Abdelsayed

Lewis Honors College Thesis Collection

The meninges are made up of three membranes; the pia mater, arachnoid mater, and dura mater, that surround the brain and spinal cord. These specialized layers work in concert with cerebrospinal fluid (CSF), to protect the central nervous system by adding a layer of cushion and removing waste products from the CNS. Additionally, the meninges act as a physical barrier between the central nervous system and the periphery. The meningeal lymphatic system is a specialized group of vessels that lie within the meninges that assist in the flow of fluid and waste products from the brain. If the meningeal lymphatic …

Age- And Sex-Dependent Alterations In Primary Somatosensory Neuronal Calcium Network Dynamics During Locomotion, Sami L. Case

Theses and Dissertations--Pharmacology and Nutritional Sciences

Over the past 30 years, the calcium (Ca2+) hypothesis of brain aging has provided clear evidence that hippocampal neuronal Ca2+ dysregulation is a key biomarker of aging. Indeed, age-dependent Ca2+-mediated changes in intrinsic excitability, synaptic plasticity, and activity have helped identify some of the mechanisms engaged in memory and cognitive decline. However, much of this work has been done at the single-cell level, mostly in slice preparations, and in restricted structures of the brain. Recently, our lab identified age- and Ca2+-related neuronal network dysregulation in the cortex of the anesthetized animal. Still, investigations in the awake animal are needed to …

Clinical And Biological Factors Determine Spinal Cord Injury Outcomes: Liquor To Lipids, Ethan Glaser

Theses and Dissertations--Physiology

Spinal cord injuries (SCI) are debilitating and life altering events that can lead to permanent motor and sensory loss. SCI outcomes are impacted by both clinical factors such as blood alcohol content (BAC) at the time of injury as well as biological factors like the lipid-rich myelin debris that accumulates in the injury site. Both clinical and biological factors contribute to SCI recovery, impacting neuroinflammation, locomotor recovery, and histopathology. The purpose of the studies described here is to investigate the role of acute alcohol intoxication and intracellular lipid processing pathways on SCI outcomes in a rodent model.

An elevated BAC …

An Investigation Of Hhv6'S Impact On The Cognitive Progression And Microglial Changes In An Alzheimer's Disease Cohort, Charles E. Seaks

Theses and Dissertations--Physiology

The role of herpesviruses and, more specifically, HHV6 in the development of Alzheimer’s disease (AD) and associated cognitive decline is still being investigated. High ubiquity and prevalence in the population have led to a high degree of skepticism about HHV6 as a potential contributor to cognitive decline and dementias. However, recent evidence related to another herpesvirus, herpes simplex virus 1, suggests that reactivation, not carriage, of the virus may be the key factor to explain the dissonance between the virus’ ubiquity and contributions to dementias. With that in mind, we set out to assess cases from the Sanders-Brown Center on …

Membrane Palmitoylated Protein Magu-3 Regulates The C. Elegans Locomotor Circuit Via Modulation Of Cholinergic Activity, Henry Richburg

Theses and Dissertations--Medical Sciences

Precise coordination of the activity and transmission in excitatory and inhibitory neural circuits is essential for healthy information flow. Synaptic scaffolding proteins play a key role in the regulation of circuit activity through the localization and organization of receptors, channels, and other synaptic machinery to facilitate signal transduction. Using the C. elegans motor circuit which has both cholinergic (excitatory) and GABAergic (inhibitory) inputs onto muscles, we revealed an unexplored role of a family of scaffolding molecules known as membrane palmitoylated proteins (MPPs). Here, we examined magu-3, a C. elegans ortholog within the membrane palmitoylated protein family, using GFP tagging …

Apoe Genotype And Cerebral Glucose Metabolism: A Multi-Omics Approach, Holden C. Williams

Theses and Dissertations--Physiology

Apolipoprotein E (APOE) is encoded by the APOE gene, present in humans as three main isoforms (E2, E3, and E4). E4 carriers face up to a 15-fold increased risk for developing late-onset Alzheimer’s disease (AD), while E2 carriers are protected. Understanding the risk conferred by E4 has been an extensive research focus for nearly three decades, but the exact mechanism has yet to be proven. Many studies have demonstrated attenuated roles of E4 in classical hallmarks of AD, notably amyloid processing and neurofibrillary formation, which normally present later in disease progression. How APOE influences hallmarks that present much earlier are …

Uncovering The Role Of Apoe4 On Alzheimer’S Disease-Related Neuroinflammation, Courtney Marie Kloske

Theses and Dissertations--Physiology

Alzheimer’s disease (AD) is the most common neurodegenerative disease and is characterized by two hallmark pathologies: amyloid-beta plaques (Ab plaques) and hyperphosphorylated, aggregated tau tangles. These pathologies are typically accompanied by the presence of neuroinflammation which is primarily mediated by microglia. Interestingly, several genetic risk factors that increase the risk of AD also have direct impacts on neuroinflammation. Of interest, Apolipoprotein E (ApoE) is the largest genetic risk factor for AD. ApoE has three isoforms- E4 confers an increased risk for AD, E3 is considered the “control” phenotype, and E2 is protective against AD. E4 plays a role in virtually …

Peripheral And Central Glucose Flux In Type I Diabetes, Jelena Anna Juras

Theses and Dissertations--Neuroscience

Diabetes is a complex metabolic disorder, of which high blood glucose concentration is the primary hallmark. Type I diabetes mellitus (T1DM) is characterized by the lack of insulin production, due to a poorly understood autoinflammatory cascade. In the words of historian Barnett “Diabetes may no longer be a death sentence, but for more and more people in the 21st century, it will become a life sentence”, making it the focal point of many research groups. It is estimated that around 20 million individuals worldwide live with T1DM.

Effects of long-term chronically elevated blood glucose are not only seen in micro/macro-vascular …

Development Of Fluorescence Based Approaches To Understand Astrocyte Biology In The Context Of Nicotine And Nicotinic Receptor Activity, Surya P. Aryal

Theses and Dissertations--Chemistry

Smoking and tobacco use (STU) is a major global health problem and worldwide more than six million people die due to tobacco related diseases each year. Although majority of smokers try to quit smoking several times in their life, traditional therapeutic approaches, which focus only on neuronal cells, have a very low success rate. Understanding the effect of nicotine on glial cells, synaptic communication and blood vasculature in the brain can provide further insights on the neurobiology of substance abuse and can potentially help to design better therapeutic approaches. Glial cells are non-excitable cells in the brain which do not …

Investigating Mechanisms Of Injury And Intervention In A Novel In Vitro Model Of Traumatic Brain Injury In Organotypic Hippocampal Slice Cultures, Julia Elaine Jagielo-Miller

Theses and Dissertations--Psychology

Traumatic brain injuries (TBIs) impact millions of individuals each year and can pose long term consequences. Despite numerous attempts, no medication has been approved by the FDA to treat TBIs. The causes of these failed trials are multifaceted, but in part can be attributed to the complex nature of TBIs, as well as a lack of sufficient pre-clinical data. In vitro models of TBI are an important tool to help understand the cellular changes seen following the injury, in a highly controlled environment. For the following experiments, a novel model of TBI was used to injure organotypic hippocampal slice cultures, …

Myelin, Cpla2, And Azithromycin: Modulation Of Macrophage Activation In Spinal Cord Injury Inflammation, Timothy J. Kopper

Theses and Dissertations--Physiology

Spinal cord injury (SCI) produces a chronic inflammatory state primarily mediated by macrophages consisting of resident microglia and infiltrating monocytes. These chronically activated SCI macrophages adopt a pro-inflammatory, pathological state that continues to cause additional damage after the initial injury and inhibits recovery. While the roles of macrophages in SCI pathophysiology are well documented, the factors contributing to this maladaptive response are poorly understood. Here, we identify the detrimental effects of myelin debris on macrophage physiology and demonstrate a novel, activation state-dependent role for cytosolic phospholipase-A2 (cPLA₂) in myelin- mediated potentiation of pro-inflammatory macrophage activation. Macrophage- mediated inflammatory …

Cloning And Functional Characterizations Of Circular Rnas From The Human Mapt Locus, Justin R. Welden

Theses and Dissertations--Molecular and Cellular Biochemistry

Under pathophysiological conditions, the microtubule protein tau (MAPT) forms neurofibrillary tangles that are the hallmark of sporadic Alzheimer’s disease as well as familial frontotemporal dementias linked to chromosome 17 (FTDP-17). In this work, I report that MAPT forms circular RNAs through backsplicing of exon 12 to either exon 10 or exon 7 (12→10; 12→7), and that these circular RNAs are translated into proteins.

Using stable cell lines overexpressing the circular tau RNAs 12→7 and 12→10, we have discovered that the tau circular RNA 12→7 is translated in a rolling circle, giving rise to multiple proteins. This circular RNA …

Polyglucosan Body Structure In Lafora Disease, M. Kathryn Brewer, Jean-Luc Putaux, Alberto Rondon, Annette M. Uittenbogaard, Mitchell A. Sullivan, Matthew S. Gentry

Lafora Epilepsy Cure Initiative Faculty Publications

Abnormal carbohydrate structures known as polyglucosan bodies (PGBs) are associated with neurodegenerative disorders, glycogen storage diseases (GSDs), and aging. A hallmark of the GSD Lafora disease (LD), a fatal childhood epilepsy caused by recessive mutations in the EPM2A or EPM2B genes, are cytoplasmic PGBs known as Lafora bodies (LBs). LBs result from aberrant glycogen metabolism and drive disease progression. They are abundant in brain, muscle and heart of LD patients and Epm2a^-/- and Epm2b^-/- mice. LBs and PGBs are histologically reminiscent of starch, semicrystalline carbohydrates synthesized for glucose storage in plants. In this study, we define LB architecture, …

Divergence In Neuronal Calcium Dysregulation In Brain Aging And Animal Models Of Ad, Adam Ghoweri

Theses and Dissertations--Pharmacology and Nutritional Sciences

Neuronal calcium dysregulation first garnered attention during the mid-1980’s as a key factor in brain aging, which led to the formulation of the Ca²⁺ hypothesis of brain aging and dementia. Indeed, many Ca²⁺-dependent cellular processes that change with age, including an increase in the afterhyperpolarization, a decrease in long-term potentiation, an increased susceptibility to long-term depression, and a reduction in short-term synaptic plasticity, have been identified. It was later determined that increased intracellular Ca²⁺ with age was due to increased Ca²⁺ channel density, elevated release from intracellular Ca²⁺ stores, and decreased Ca²⁺ buffering …

Involvement Of The Sigma-1 Receptor In Methamphetamine-Mediated Changes To Astrocyte Structure And Function, Richik Neogi

Theses and Dissertations--Medical Sciences

Methamphetamine is a highly addictive psychostimulant drug. There are currently no FDA-approved pharmacological treatments for methamphetamine addiction. Pharmacologically, (+)-methamphetamine is a dopamine releasing agent and dopamine transporter substrate that redistributes dopamine from intracellular vesicles via the vesicular monoamine transporter 2 (VMAT2) and reverses the direction of dopamine transport in the dopamine transporter. Methamphetamine, cocaine, and other drugs of abuse are also sigma-1 receptor ligands, and previous studies have demonstrated the role of the sigma-1 receptor in modulating the behavioral and cellular effects of these drugs. However, almost all these studies were conducted in cell culture systems or with emphasis on …

Combination Of Investigational Cell-Based Therapy And Deep Brain Stimulation To Alter The Progression Of Parkinson’S Disease, Nader El Seblani

Theses and Dissertations--Pharmacy

Parkinson’s disease (PD) is the second most common neurodegenerative disorder and the motor symptoms are caused by progressive loss of midbrain dopamine neurons. There is no current treatment that can slow or reverse PD. Our current “DBS-Plus” clinical trial (NCT02369003) features the implantation in vivo of autologous Schwann cells (SCs) derived from a patient’s sural nerve into the substantia nigra pars compacta (SNpc) in combination with Deep Brain Stimulation (DBS) therapy for treating patients with advanced PD.

The central hypothesis of our research is that transdifferentiated SCs within conditioned nerve tissue will deliver pro-regenerative factors to enhance the survival of …

Apoe As A Metabolic Regulator In Humans, Mice, And Astrocytes, Brandon C. Farmer

Theses and Dissertations--Physiology

Altered metabolic pathways appear to play central roles in the pathophysiology of late-onset Alzheimer’s disease (AD). Carrier status of the E4 allele of the APOE gene is the strongest genetic risk factor for late-onset AD, and increasing evidence suggests that E4 carriers may be at an increased risk for neurodegeneration based on inherent metabolic impairments. A new appreciation is forming for the role of APOE in cerebral metabolism, and how nutritional factors may impact this role. In chapter 1, the literature on nutritional interventions in E4 carriers aimed at mitigating disease risk is reviewed. Studies investigating the mechanism by which …

Novel Post-Translational Modification And Function Of Fus: The Relevance To Amyotrophic Lateral Sclerosis, Alexandra Arenas

Theses and Dissertations--Toxicology and Cancer Biology

Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disease characterized by the preferential death of motor neurons. Approximately 10% of ALS cases are familial and 90% are sporadic. Fused in Sarcoma (FUS) is a ubiquitously expressed RNA binding protein implicated in familial ALS and frontotemporal dementia (FTD). FUS is ubiquitously expressed in cells and has a variety of functions in the nucleus and cytoplasm. FUS mutations in the nuclear localization sequence (NLS) causes mislocalization of FUS in the cytoplasm, where it can undergo liquid-liquid phase separation and become stress granules or protein inclusions. Although FUS inclusion bodies can be found in …

Absence Of Endothelial Α5Β1 Integrin Triggers Early Onset Of Experimental Autoimmune Encephalomyelitis Due To Reduced Vascular Remodeling And Compromised Vascular Integrity, Ravi Kant, Sebok K. Halder, Gregory J. Bix, Richard Milner

Sanders-Brown Center on Aging Faculty Publications

Early in the development of multiple sclerosis (MS) and its mouse model experimental autoimmune encephalomyelitis (EAE), vascular integrity is compromised. This is accompanied by a marked vascular remodeling response, though it is currently unclear whether this is an adaptive vascular repair mechanism or is part of the pathogenic process. In light of the well-described angiogenic role for the α5β1 integrin, the goal of this study was to evaluate how genetic deletion of endothelial α5 integrin (α5-EC-KO mice) impacts vascular remodeling and repair following vascular disruption during EAE pathogenesis, and how this subsequently influences clinical progression and inflammatory demyelination. Immunofluorescence staining …

Rapid No• Measures In Rat Nucleus Accumbens And Frontal Cortex Following Nasal Administration Of Nitroglycerin, Victoria A. Scott

Theses and Dissertations--Medical Sciences

Nitric Oxide (NO) is a powerful endogenous free radical that has numerous biological functions including vasodilation and serves as a post synaptic second messenger in the central nervous system (CNS). Numerous studies implicate NO• involvement in CNS disorders such as schizophrenia and drug abuse. These studies address the direct in vivo determination of an FDA-approved NO• donor (nitroglycerin) on extracellular levels of NO• in the frontal cortex and core of the nucleus accumbens in a lightly anesthetized rat. State-of-the-art in vivo amperometric recording techniques coupled with a novel 4-channel low noise pre-amplifier system and new generation microelectrode arrays (MEAs) will …

Biochemical Approaches For The Diagnosis And Treatment Of Lafora Disease, Mary Kathryn Brewer

Theses and Dissertations--Molecular and Cellular Biochemistry

Glycogen is the sole carbohydrate storage molecule found in mammalian cells and plays an important role in cellular metabolism in nearly all tissues, including the brain. Defects in glycogen metabolism underlie the glycogen storage diseases (GSDs), genetic disorders with variable clinical phenotypes depending on the mutation type and affected gene(s). Lafora disease (LD) is a fatal form of progressive myoclonus epilepsy and a non-classical GSD. LD typically manifests in adolescence with tonic-clonic seizures, myoclonus, and a rapid, insidious progression. Patients experience increasingly severe and frequent epileptic episodes, loss of speech and muscular control, disinhibited dementia, and severe cognitive decline; death …

The Role Of Endoplasmic Reticulum Stress In Ethanol-Induced Neurodegeneration, Yongchao Wang

Theses and Dissertations--Pharmacology and Nutritional Sciences

Heavy ethanol use causes neurodegeneration manifested by neuronal loss and dysfunction. It is becoming imperative to delineate the underlying mechanism to promote the treatment of ethanol-induced neurodegeneration. Endoplasmic reticulum (ER) stress is a hallmark and an underlying mechanism of many neurodegenerative diseases. This study aims to investigate the role of ER stress in ethanol-induced neurodegeneration. In experimental design, adult mice were exposed to binge ethanol drinking by daily gavage for 1, 5, or 10 days and the response of ER stress was examined. We found the induction of ER stress appeared at 5 days and remained at 10 days. Moreover, …

Exploring The Role Of Insulin Receptor Signaling In Hippocampal Learning And Memory, Neuronal Calcium Dysregulation, And Glucose Metabolism, Hilaree N. Frazier

Theses and Dissertations--Pharmacology and Nutritional Sciences

In the late 90’s, emerging evidence revealed that the brain is insulin-sensitive, highlighted by broad expression of brain-specific insulin receptors and reports of circulating brain insulin. Contemporary literature robustly supports the role of insulin signaling in normal brain function and suggests that insulin-related processes diminish with aging, evidenced by decreased signaling markers, reduced insulin receptor density, and lower levels of insulin transport across the blood-brain barrier. In the context of pathological cognitive decline, clinical trials using intranasal insulin delivery have reported positive outcomes on memory and learning in patients with mild cognitive decline or early-stage Alzheimer’s disease. However, while the …

Autologous Peripheral Nerve Grafts To The Brain For The Treatment Of Parkinson's Disease, Andrew Welleford

Theses and Dissertations--Neuroscience

Parkinson’s disease (PD) is a disorder of the nervous system that causes problems with movement (motor symptoms) as well as other problems such as mood disorders, cognitive changes, sleep disorders, constipation, pain, and other non-motor symptoms. The severity of PD symptoms worsens over time as the disease progresses, and while there are treatments for the motor and some non-motor symptoms there is no known cure for PD. Thus there is a high demand for therapies to slow the progressive neurodegeneration observed in PD. Two clinical trials at the University of Kentucky College of Medicine (NCT02369003, NCT01833364) are currently underway that …

The Effects Of A Ketone Body On Synaptic Transmission, Alexandra Elizabeth Stanback

Theses and Dissertations--Biology

The ketogenic diet is commonly used to control epilepsy, especially in cases when medications cannot. The diet typically consists of high fat, low carb, and adequate protein and produces a metabolite called acetoacetate. Seizure activity is characterized by glutamate excitotoxicity and therefore glutamate regulation is a point of research for control of these disorders. Acetoacetate is heavily implicated as the primary molecule responsible for decreasing glutamate in the synapse; it is believed that acetoacetate interferes with the transport of glutamate into the synaptic vesicles. The effects on synaptic transmission at glutamatergic synapses was studied in relation to the ketogenic diet …

Neuroprotective Strategies Following Experimental Traumatic Brain Injury: Lipid Peroxidation-Derived Aldehyde Scavenging And Inhibition Of Mitochondrial Permeability Transition, Jacqueline Renee Kulbe

Theses and Dissertations--Neuroscience

Traumatic brain injury (TBI) represents a significant health crisis. To date there are no FDA-approved pharmacotherapies available to prevent the neurologic deficits caused by TBI. Following TBI, dysfunctional mitochondria generate reactive oxygen and nitrogen species, initiating lipid peroxidation (LP) and the formation of LP-derived neurotoxic aldehydes, which bind mitochondrial proteins, exacerbating dysfunction and opening of the mitochondrial permeability pore (mPTP), resulting in extrusion of mitochondrial sequestered calcium into the cytosol, and initiating a downstream cascade of calpain activation, spectrin degradation, neurodegeneration and neurologic impairment.

As central mediators of the TBI secondary injury cascade, mitochondria and LP-derived neurotoxic aldehydes make promising …

Mutations Of Fus Cause Aggregation Of Rna Binding Proteins, Disruptions In Protein Synthesis, And Dysregulation Of Nonsense Mediated Decay, Marisa Elizabeth Kamelgarn

Theses and Dissertations--Toxicology and Cancer Biology

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by motor neuron death and subsequent muscle atrophy. Approximately 15% of ALS cases are inheritable, and mutations in the Fused in Sarcoma (FUS) gene contribute to approximately 5% of these cases, as well as about 2% of sporadic cases. FUS performs a diverse set of cellular functions, including being a major regulator of RNA metabolism. FUS undergoes liquid- liquid phase transition in vitro, allowing for its participation in stress granules and RNA transport granules. Phase transition also contributes to the formation of cytoplasmic inclusions found in the …

An Aged Canid With Behavioral Deficits Exhibits Blood And Cerebrospinal Fluid Amyloid Beta Oligomers, Clare Rusbridge, Francisco J. Salguero, Monique Antoinette David, Kiterie M. E. Faller, Jose T. Bras, Rita J. Guerreiro, Angela C. Richard-Londt, Duncan Grainger, Elizabeth Head, Sebastian G. P. Brandner, Brian Summers, John Hardy, Mourad Tayebi

Pharmacology and Nutritional Sciences Faculty Publications

Many of the molecular and pathological features associated with human Alzheimer disease (AD) are mirrored in the naturally occurring age-associated neuropathology in the canine species. In aged dogs with declining learned behavior and memory the severity of cognitive dysfunction parallels the progressive build up and location of Aβ in the brain. The main aim of this work was to study the biological behavior of soluble oligomers isolated from an aged dog with cognitive dysfunction through investigating their interaction with a human cell line and synthetic Aβ peptides. We report that soluble oligomers were specifically detected in the dog's blood and …

Alterations In Gabaergic Nts Neuron Function In Association With Tle And Sudep, Isabel Diane Derera

Theses and Dissertations--Physiology

Epilepsy is a neurological disorder that is characterized by aberrant electrical activity in the brain resulting in at least two unprovoked seizures over a period longer than 24 hours. Approximately 60% of individuals with epilepsy are diagnosed with temporal lobe epilepsy (TLE) and about one third of those individuals do not respond well to anti-seizure medications. This places those individuals at high risk for sudden unexpected death in epilepsy (SUDEP). SUDEP is defined as when an individual with epilepsy, who is otherwise healthy, dies suddenly and unexpectedly for unknown reasons. SUDEP is one of the leading causes of death in …