Neurosciences Commons^™

Regulation Of System XC- By Pharmacological Manipulation Of Cellular Thiols, Rebecca Albano, Nicholas J. Raddatz, Julie Hjelmhaug, David A. Baker, Doug Lobner

Biomedical Sciences Faculty Research and Publications

The cystine/glutamate exchanger (system x_c^-) mediates the transport of cystine into the cell in exchange for glutamate. By releasing glutamate, system x_c^- can potentially cause excitotoxicity. However, through providing cystine to the cell, it regulates the levels of cellular glutathione (GSH), the main endogenous intracellular antioxidant, and may protect cells against oxidative stress. We tested two different compounds that deplete primary cortical cultures containing both neurons and astrocytes of intracellular GSH, L-buthionine-sulfoximine (L-BSO), and diethyl maleate (DEM). Both compounds caused significant concentration and time dependent decreases in intracellular GSH levels. However; DEM caused an increase …

Development Of An Avian Model For Identifying Individual Differences In Drug Vulnerability, Beth A. Rice

Theses and Dissertations--Psychology

The attribution of incentive salience to cues that become associated with drugs of abuse is a critical characteristic of individuals who may be vulnerable to drug addiction. Rodents with the propensity to sign track are thought to be vulnerable to drug abuse. The goal of the current work was to investigate whether sign trackers (STs) would acquire cocaine conditioned place preference (CPP) to a discrete cue using an avian species. In Experiment 1, sign and goal trackers (GTs) were first identified using a one third rank order split. Following identification, cocaine-CPP was conducted with a discrete cue in each end …

Effects Of Hiv-1 Viral Protein Tat On The Viability And Function Of Oligodendroglial Cells, Shiping Zou

Theses and Dissertations

Myelin pallor is frequently reported in HIV patients, and can occur in the CNS prior to other evidence of disease process. Our exploratory studies showed that oligodendrocytes (OLs) are direct targets of HIV-1 Tat (transactivator of transcription). Tat induces a dose-dependent increase of intracellular Ca²⁺ level ([Ca²⁺]_i) in cultured murine OLs, which can be attenuated by ionotropic glutamate receptor (iGluR) antagonists MK801 and CNQX. The Tat-induced [Ca²⁺]_i increase leads to increased death in immature (O4⁺, MBP^-), but not mature (O4⁺, MBP⁺) OLs, over 96 …

Meta-Analysis Of Gene Expression Studies, Umaporn Siangphoe

Theses and Dissertations

Combining effect sizes from individual studies using random-effects models are commonly applied in high-dimensional gene expression data. However, unknown study heterogeneity can arise from inconsistency of sample qualities and experimental conditions. High heterogeneity of effect sizes can reduce statistical power of the models. We proposed two new methods for random effects estimation and measurements for model variation and strength of the study heterogeneity. We then developed a statistical technique to test for significance of random effects and identify heterogeneous genes. We also proposed another meta-analytic approach that incorporates informative weights in the random effects meta-analysis models. We compared the proposed …

Psychoactive Synthetic Cathinones (Or 'Bath Salts'): Investigation Of Mechanisms Of Action, Farhana Sakloth

Theses and Dissertations

Synthetic cathinones represent threatening and high abuse-potential designer drugs. These are analogs of cathinone (the b-keto analog of amphetamine (AMPH)) a naturally occurring stimulant found in the plant Catha Edulis. Methcathinone (MCAT) was the first synthetic analog of cathinone to be identified in 1987 by Glennon and co-workers and it exerted its action primarily through the dopamine transporter (DAT). Most central stimulants exert their action via monomaine transporters by causing either the release (e.g. cathinone analogs such as MCAT) or by preventing the reuptake (e.g. cocaine) of the neurotransmitter dopamine (DA) thus increasing the extracellular synaptosomal concentration of this …

Effects Of Hiv-1 Tat On The Enteric Nervous, Joy Ngwainmbi

Theses and Dissertations

More than 1.2 million people are estimated to be currently living with the human immunodeficiency virus (HIV) in the United States of America. The gastrointestinal (GI) tract is both a major target and an important component of HIV pathogenesis. The GI processes that are dysregulated during HIV infection are controlled by the enteric nervous system (ENS). Indeed, both clinical and experimental studies have implicated the ENS in HIV and simian immunodeficiency virus (SIV) pathogenesis. In addition to direct viral effects, the HIV virus also indirectly affects the GI tract via cellular and/or viral toxins released by infected cells. Trans-activator of …

Sigma Receptor Activation Mitigates Toxicity Evoked By The Convergence Of Ischemia, Acidosis And Amyloid-Beta, Adam Alexander Behensky

USF Tampa Graduate Theses and Dissertations

Stroke is the fifth leading cause of death in the United States and a major cause of long-term disability in industrialized countries. The core region of an ischemic stroke dies within minutes due to activation of necrotic pathways. Outside of this core region is the penumbral zone, where some perfusion is maintained via collateral arteries. Delayed cell death occurs in this area due to the triggering of apoptotic mechanisms, which expands the ischemic injury over time. The cellular and molecular events that produce the expansion of the ischemic core continue to be poorly understood. The increases in the amyloid precursor …

Neuroinflammatory Alterations Via Cd-36 In Traumatic Brain Injury, Diana G. Hernandez-Ontiveros

USF Tampa Graduate Theses and Dissertations

Traumatic brain injury (TBI) has become an increasingly unmet clinical need due to intense military conflicts worldwide. Directly impacted brain cells suffer massive death, with neighboring cells succumbing to progressive neurodegeneration accompanied by inflammatory and other secondary cell death events. Subsequent neurodegenerative events may extend to normal areas beyond the core of injury, thereby exacerbating the central nervous system’s inflammatory response to TBI. Recently CD-36 (cluster of differentiation 36/fatty acid translocase (FAT), a class B scavenger receptor of modified low-density lipoproteins (mLDLs) in macrophages, has been implicated in lipid metabolism, atherosclerosis, oxidative stress, and tissue injury in cerebral ischemia, and …

Attentional Allocation In Language Processing In Adults Who Stutter: Erp Evidence, Wendy Lorraine Olsen

USF Tampa Graduate Theses and Dissertations

The aim of this study was to investigate how young adults who stutterer allocate attentional resources during two linguistic stages in picture naming, specifically lemma and lexeme retrieval. This study reports on behavioral and brain electrophysiological data collected during a simple auditory oddball task and a Dual Picture-Word Interference/Tone Monitoring Task.

Preparing The Periphery For A Subsequent Behavior: Motor Neuronal Activity During Biting Generates Little Force But Prepares A Retractor Muscle To Generate Larger Forces During Swallowing In Aplysia, Hui Lu, Jeffrey M. Mcmanus, Miranda J. Cullins, Hillel J. Chiel

Faculty Scholarship

Some behaviors occur in obligatory sequence, such as reaching before grasping an object. Can the earlier behavior serve to prepare the musculature for the later behavior? If it does, what is the underlying neural mechanism of the preparation? To address this question, we examined two feeding behaviors in the marine mollusk Aplysia californica, one of which must precede the second: biting and swallowing. Biting is an attempt to grasp food. When that attempt is successful, the animal immediately switches to swallowing to ingest food. The main muscle responsible for pulling food into the buccal cavity during swallowing is the I3 …

A Quantum Theory Of Consciousness May Require A Paradigm Shift In Biology, Maurice Goodman

Articles

It is often assumed that the known physical laws form a closed system and are complete. It is also assumed that biological theories require no additional principles that are fundamental other than those we already know. Assumptions such as these are acting as a barrier to progress in biological theories and an understanding of consciousness. This paper examines the unexplained inconsistencies among fundamental particles and forces and the fundamental gaps in our knowledge of biology and the cell in particular that may impact on such progress. Also, the laws of quantum mechanics are examined and found to be grossly incomplete. …

Inflamation And Oxidative Stress : The Molecular Connectivity Between Insulin Resistance, Obesity And Alzheimer's Disease, Guiseppe Verdile, Kevin N. Keane, Vinicius F. Cruzat, Sandra Medic, Miheer Sabale, Joanne Rowles, Nadeeja Wijesekara, Ralph Martins, Paul E. Fraser, Philip Newsholme

Research outputs 2014 to 2021

Type 2 diabetes (T 2 DM), Alzheimer’s disease (AD), and insulin resistance are age-related conditions and increased prevalence is of public concern. Recent research has provided evidence that insulin resistance and impaired insulin signalling may be a contributory factor to the progression of diabetes, dementia, and other neurological disorders. Alzheimer’s disease (AD) is the most common subtype of dementia. Reduced release (for T 2 DM) and decreased action of insulin are central to the development and progression of both T 2 DM and AD. A literature search was conducted to identify molecular commonalities between obesity, diabetes, and AD. Insulin resistance …

An Investigation Of The Relationship Between Axonal Injury, Biomarker Expression And Mechanical Response In A Rodent Head Impact Acceleration Model, Yan Li

Wayne State University Dissertations

In the United States 1.4 million people sustain traumatic brain injury (TBI) each year, resulting in 235,000 hospitalizations and 50,000 fatalities annually. Traumatic axonal injury (TAI) is a serious outcome of TBI that accounts for 40-50% of hospitalizations due to head injury and one third of the mortality due to TBI, and it is difficult to diagnose and evaluate. The purpose of this dissertation is to determine mechanical injury predictors for TAI and identify potential biomarkers to evaluate TAI.

In this dissertation, a modified Marmarou impact acceleration injury model was developed to allow the monitoring of velocity of the impactor …

Amyloid-Related Memory Decline In Preclinical Alzheimer's Disease In Dependent On Apoe Ε4 And Is Detectable Over 18-Months, Christine Thai, Yen Ying Lim, Victor L. Villemagne, Simon Laws, David Ames, Kathryn A. Ellis, Stephanie Rainey-Smith, Ralph Martins, Colin L. Masters, Christopher C. Rowe, Paul Maruff, Australian Imaging, Biomarkers And Lifestyle (Aibl) Research Group

Research outputs 2014 to 2021

High levels of β-amyloid (Aβ) in the brain and carriage of the APOE ε4 allele have each been linked to cognitive impairment in cognitively normal (CN) older adults. The aim of this study was to investigate the relationship between cerebral Aβ level, APOE ε4 carrier status, and cognitive decline over 18 monthes, in 317 cognitively healthy (CN) older adults (47% males, 52.4% females) aged between 60 and 89 years (Mean = 69.9, SC = 6.8). Cognition was assessed using the Cogstate Brief Battery (CBB) and the California Verbal Learning Test, Second Edition (CVLT-II). Planned comparisons indicated that CN older adults …

Expression Patterns Of Bdnf With Central Anorexigenic Signaling Pathways Involving Pacap In The Hypothalamic Ventromedial Nuclei, Brian Maunze, Matthew M. Hurley, Jon M. Resch, M. J. Reilley, E. M. Wassmann, Sujean Choi

Biomedical Sciences Faculty Research and Publications

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a 38-amino acid polypeptide belonging to the secretin super family of peptides. PACAP binds to its type 1 receptor (PAC1R) with greater affinity than for the receptors for vasoactive intestinal polypeptides (VIP), VPAC1 and VPAC2. Although mRNA for PACAP and its receptor PAC1R are found throughout the central nervous system, they are abundantly expressed in the hypothalamic ventromedial nuclei (VMN). In male Sprague Dawley rats, infusions of PACAP into the VMN produce a robust decrease in food intake with concomitant increased energy expenditure, decreased body weight, and significantly elevated brain-derived neurotrophic factor (BDNF) mRNA …

A New Obesity Model Reveals The Hypophagic Properties Of Pacap Involve The Regulation Of Homeostatic Feeding In The Ventromedial Hypothalamic Nucleus And Hedonic Feeding In The Nucleus Accumbens, Matthew M. Hurley, Brian Maunze, Jon M. Resch, Mogen M. Frenkel, M. J. Reilley, Megan E. Block, David A. Baker, Sujean Choi

Biomedical Sciences Faculty Research and Publications

Binge eating in humans is a complex disorder that often involves discrete, compulsive feeding sessions of highly palatable foods even in the absence of a deprivation state or hunger. Binging can be effectively modeled in rodents by providing subjects with limited access to a palatable food source (Western Diet; WD) as an adjunct to ad lib access to normal chow (Standard Chow; SC). Although this design recapitulates several fundamental characteristics observed in binge eating disorder, the binge eating observed in this paradigm is likely a product of both hedonic and homeostatic drives with the need to balance energy stores still …

Pacap And Cocaine Reinstatement: A Neuropeptide Expressed By Corticostriatal Neurons That Regulates Nucleus Accumbens Astrocytes, Linghai Kong, E. Hess, Brian Maunze, Matthew M. Hurley, Khadijah Makky, Sujean Choi, John R. Mantsch, David A. Baker

Biomedical Sciences Faculty Research and Publications

Drug addiction involves heightened relapse vulnerability arising from persistent drug-induced neuro-adaptations, including a) hypofrontality which is thought to reflect reduced firing of cortical afferents to the nucleus accumbens (NAcc) and b) altered glutamate homeostasis in NAcc that likely involves reduced glutamate release and uptake by astrocytes. An important question is whether these forms of pathological plasticity are functionally linked such that reduced corticostriatal firing may result in aberrant regulation of astrocytes in the NAcc. To begin to evaluate this possibility, we first determined whether neurons regulate system xc- (Sxc) activity, a mechanism of non-vesicular glutamate release by astrocytes. We found …

Strategies For Preventing Age And Neurodegenerative Disease-Associated Mitochondrial Dysfunction, Vedad Delic

USF Tampa Graduate Theses and Dissertations

Mitochondrial dysfunction plays a pivotal role in the development of aging phenotypes and aging-associated neurodegenerative disorders, such as Alzheimer’s disease (AD), Parkinson’s disease (PD) and Amyotrophic lateral sclerosis (ALS). Strategies that restore mitochondrial dysfunction may rescue the deficits of central metabolism in these disorders and improve cell survival. For example, we found that modulating the mTOR signaling pathway in a tissue culture model of aging-induced mitochondrial DNA mutation enhanced mitochondrial function as evidenced by increased oxygen consumption. Our previous melatonin studies also led us to hypothesize that caloric restriction and the hormone melatonin would reverse brain mitochondrial dysfunction in animal …

Minocycline Treatment And The Necessity To Develop A Novel Outcome Measure For Children With Angelman Syndrome, Joseph Christopher Grieco

USF Tampa Graduate Theses and Dissertations

Angelman syndrome (AS) is a rare genetic disorder affecting 1/10,000 to 1/20,000 births. This disorder arises through the genetic disruption of the maternal UBE3A allele, which when coupled with epigenetic silencing of the paternal allele UBE3A allele, gives rise to an absence of UBE3A protein in the central nervous system. Clinical manifestations of the syndrome vary in severity and include poor motor function, deficits in language and severe intellectual impairments. Previous research in the Angelman syndrome mouse model revealed abnormalities in dendritic spine density and morphology of hippocampal pyramidal cells. As seen in humans with AS, mice show abnormal behavioral …

Effects Of Nicotine Withdrawal On Motivation, Reward Sensitivity And Reward-Learning, Jason A. Oliver

USF Tampa Graduate Theses and Dissertations

Research on addictive behavior has traditionally emphasized the role that primary reinforcing effects of drugs of abuse plays in the development and maintenance of dependence. However, contemporary behavioral economic theory and animal models of nicotine dependence suggest the need for greater attention to the impact that response to alternative rewards may have on smoking behavior. The present study sought to investigate the impact of nicotine withdrawal on self-report, behavioral and neural indices of motivation, immediate response to rewards and the capacity to learn and modify behavior in response to positive and negative feedback. Heavy smokers (n = 48) completed two …

Accommodating Hyperaroused Information Processing In Persons At Risk For Alcoholism, Kellianne Clark, Jaclyn Cutler

Student Scholar Symposium Abstracts and Posters

In the search for the factors related to the heightened alcoholism risk in adult children of alcoholics (ACOA), it has been reported that these persons possess a high incidence of attention deficit disorders (ADD) as determined by clinical assessment instruments. However, investigations of alcoholism risk and ADD indicate that, in contrast to the hypoarousal model of ADD, the ACOA’s attention problems represent hyperarousal of attention mechanisms resulting in reduced ability to select and encode relevant information. If true, then unlike persons with ADD, clinical and cognitive assessments of ACOAs would benefit if the ACOA was provided with more time to …

A Randomized Noninferiority Trial Of Condensed Protocols For Genetic Risk Disclosure Of Alzheimer's Disease, Peter J. Whitehouse, Melissa Barber Butson

Faculty Scholarship

Introduction Conventional multisession genetic counseling is currently recommended when disclosing apolipoprotein E (APOE) genotype for the risk of Alzheimer's disease (AD) in cognitively normal individuals. The objective of this study was to evaluate the safety of brief disclosure protocols for disclosing APOE genotype for the risk of AD. Methods A randomized, multicenter noninferiority trial was conducted at four sites. Participants were asymptomatic adults having a first-degree relative with AD. A standard disclosure protocol by genetic counselors (SP-GC) was compared with condensed protocols, with disclosures by genetic counselors (CP-GC) and by physicians (CP-MD). Preplanned co-primary outcomes were anxiety and depression scales …

Long-Acting Antituberculous Therapeutic Nanoparticles Target Macrophage Endosomes., Benson J. Edagwa, Dongwei Guo, Pavan Puligujja, Han Chen, Joellyn Mcmillan, Xinming Liu, Howard Gendelman, Prabagaran Narayanasamy

Journal Articles: Pharmacology & Experimental Neuroscience

Eradication of Mycobacterium tuberculosis (MTB) infection requires daily administration of combinations of rifampin (RIF), isoniazid [isonicotinylhydrazine (INH)], pyrazinamide, and ethambutol, among other drug therapies. To facilitate and optimize MTB therapeutic selections, a mononuclear phagocyte (MP; monocyte, macrophage, and dendritic cell)-targeted drug delivery strategy was developed. Long-acting nanoformulations of RIF and an INH derivative, pentenyl-INH (INHP), were prepared, and their physicochemical properties were evaluated. This included the evaluation of MP particle uptake and retention, cell viability, and antimicrobial efficacy. Drug levels reached 6 μg/10(6) cells in human monocyte-derived macrophages (MDMs) for nanoparticle treatments compared with 0.1 μg/10(6) cells for native drugs. …

Measuring The Role Of Inhibition In Auditory Discrimination In Mice, Tazima Nur

Graduate Theses and Dissertations

Understanding how inhibitory neurons affect sensory information processing in the cerebral cortex is an ongoing goal of both neuroscience and statistical physics research. In this master's thesis research project, an experimental system has been designed and built for studying how auditory dynamic range depends on inhibitory neurons, based on observations of mouse behavior. In this thesis, firstly, the topic of inhibition and information processing has been introduced. Then two papers related to inhibition and dynamic range has been reviewed in detail. One of the papers is an experimental work that analyzes the affect of inhibition on dynamic range. The other …

Postural Sway And Brain Hemispheric Power Spectral Density Under Different Attentional Focus Conditions, Sharon Jalene

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to determine the differences, if any, in the root mean square error (RMSE) of postural sway and hemispheric power spectral density (PSD) in the alpha and beta bands (8-12Hz and 12-25Hz) during different conditions of attentional focus (i.e., internal focus (IF), and external focus (EF) and a control condition (C)). Previous studies have shown that the adoption of IF and EF significantly alter motor performance and that EF promotes automaticity (Wulf, 2013). Sports performance and balance studies utilizing EEG spectral analyses report increased alpha oscillations during expert performance and stable balance and increased beta …

Genetic And Chemical Dissection Of Bloodbrain Barrier Development In Zebrafish, Robyn Anne Umans

Theses and Dissertations (ETD)

The blood-brain barrier (BBB) maintains a homeostatic environment as well as prohibits the entrance of xenobiotics into the brain. Because of these qualities, drug delivery is a fundamental challenge for the treatment of many diseases of the central nervous system (CNS). Along with limiting the access of therapeutics into the brain, the BBB is also impaired in CNS pathologies. Understanding the molecular cues that are essential for healthy BBB development and integrity may reveal targets for drug delivery leading to decreased progression or possible treatment of many detrimental CNS diseases. While the central features of the BBB have been accepted, …

Behavioral Assessment Of Acute Inhibition Of System XC - In Rats, Victoria Lutgen, Jon M. Resch, Krista Qualmann, Nicholas J. Raddatz, Cristina Panhans, Ellen M. Olander, Linghai Kong, Sujean Choi, John R. Mantsch, David A. Baker

Biomedical Sciences Faculty Research and Publications

Rationale

Gaps in our understanding of glutamatergic signaling may be key obstacles in accurately modeling complex CNS diseases. System x_c ^- is an example of a poorly understood component of glutamate homeostasis that has the potential to contribute to CNS diseases.

Objectives

This study aims to determine whether system x_c ^- contributes to behaviors used to model features of CNS disease states.

Methods

In situ hybridization was used to map mRNA expression of xCT throughout the brain. Microdialysis in the prefrontal cortex was used to sample extracellular glutamate levels; HPLC was used to measure extracellular glutamate and tissue …

Hemispheric Asymmetry In The Perception Of Musical Pitch Structure, Matthew Adam Rosenthal

UNLV Theses, Dissertations, Professional Papers, and Capstones

Both the left and right hemispheres contribute to the perception of pitch structure

in music. Music researchers have attempted to explain the observed asymmetries in the perception of musical pitch structure by characterizing the dominant processing style of each hemisphere. However, no existing characterizations have been able to account for all of the empirical findings. To better explain existing empirical findings, this dissertation characterizes the left hemisphere as dominant in temporal pitch processing (i.e. with respect to the sequential ordering of pitches) and the right hemisphere as dominant in non-temporal pitch processing (i.e. without respect to the sequential ordering of …

Augmented Cystine–Glutamate Exchange By Pituitary Adenylate Cyclase-Activating Polypeptide Signaling Via The Vpac1 Receptor, Jon M. Resch, Rebecca Albano, Xiaoqian Liu, Julie Hjelmhaug, Doug Lobner, David A. Baker, Sujean Choi

Biomedical Sciences Faculty Research and Publications

In the central nervous system, cystine import in exchange for glutamate through system x_c^- is critical for the production of the antioxidant glutathione by astrocytes, as well as the maintenance of extracellular glutamate. Therefore, regulation of system x_c^- activity affects multiple aspects of cellular physiology and may contribute to disease states. Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuronally derived peptide that has already been demonstrated to modulate multiple aspects of glutamate signaling suggesting PACAP may also target activity of cystine–glutamate exchange via system x_c^-. In this study, 24-h treatment of primary cortical …

In Vivo Identification Of Eugenol-Responsive And Muscone-Responsive Mouse Odorant Receptors, Timothy S. Mcclintock, Kaylin Adipietro, William B. Titlow, Patrick Breheny, Andreas Walz, Peter Mombaerts, Hiroaki Matsunami

Physiology Faculty Publications

Our understanding of mammalian olfactory coding has been impeded by the paucity of information about the odorant receptors (ORs) that respond to a given odorant ligand in awake, freely behaving animals. Identifying the ORs that respond in vivo to a given odorant ligand from among the ∼1100 ORs in mice is intrinsically challenging but critical for our understanding of olfactory coding at the periphery. Here, we report an in vivo assay that is based on a novel gene-targeted mouse strain, S100a5-tauGFP, in which a fluorescent reporter selectively marks olfactory sensory neurons that have been activated recently in vivo. Because each …