Neuroscience and Neurobiology Commons^™

Role Of Nucleus Accumbens Dopamine Receptor Signaling In The Suppression Of Punished Reward Seeking, Grace M. Joyner, Anna Caroline Toburen

Senior Theses

Previous studies have shown that within the nucleus accumbens (NAc), a brain region associated with motivation and reinforcement learning, activity of neurons expressing the dopamine D2 receptor (D2R neurons) act as a “break” on risky behavior associated with negative outcomes. Moreover, when these neurons are stimulated, rats were found to become more risk averse. However, the impact of dopamine signaling through NAc D2R neurons in risk avoidance is still unclear. To further explore the role of NAc dopamine signaling in punished reward-seeking, we tested rats in a novel punished food-seeking paradigm in which subjects are trained to choose between a …

Glycemic Challenge Is Associated With The Rapid Cellular Activation Of The Locus Ceruleus And Nucleus Of Solitary Tract: Circumscribed Spatial Analysis Of Phosphorylated Map Kinase Immunoreactivity, Arshad Khan

Selected Works Temporary Series

Rodent studies indicate that impaired glucose utilization or hypoglycemia is associated with the cellular activation of neurons in the medulla (Winslow, 1733) (MY), believed to control feeding behavior and glucose counterregulation. However, such activation has been tracked primarily within hours of the challenge, rather than sooner, and has been poorly mapped within standardized brain atlases. Here, we report that, within 15 min of receiving 2-deoxy-D-glucose (2-DG; 250 mg/kg, i.v.), which can trigger glucoprivic feeding behavior, marked elevations were observed in the numbers of rhombic brain (His, 1893) (RB) neuronal cell profiles immunoreactive for the cellular activation marker(s), phosphorylated p44/42 MAP …

Glycemic Challenge Is Associated With The Rapid Cellular Activation Of The Locus Ceruleus And Nucleus Of Solitary Tract: Circumscribed Spatial Analysis Of Phosphorylated Map Kinase Immunoreactivity, Khan

Departmental Papers (Biology)

Rodent studies indicate that impaired glucose utilization or hypoglycemia is associated with the cellular activation of neurons in the medulla (Winslow, 1733) (MY), believed to control feeding behavior and glucose counterregulation. However, such activation has been tracked primarily within hours of the challenge, rather than sooner, and has been poorly mapped within standardized brain atlases. Here, we report that, within 15 min of receiving 2-deoxy-D-glucose (2-DG; 250 mg/kg, i.v.), which can trigger glucoprivic feeding behavior, marked elevations were observed in the numbers of rhombic brain (His, 1893) (RB) neuronal cell profiles immunoreactive for the cellular activation marker(s), phosphorylated p44/42 MAP …

Cervical Spinal Cord Injury Leads To Injury And Altered Metabolism In The Lungs, Emily E. Huffman, Brittany E. Dong, Harrison A. Clarke, Lyndsay E. A. Young, Matthew S. Gentry, Derek B. Allison, Ramon C. Sun, Christopher M. Waters, Warren J. Alilain

Saha Cardiovascular Research Center Faculty Publications

High-cervical spinal cord injury often disrupts respiratory motor pathways and disables breathing in the affected population. Moreover, cervically injured individuals are at risk for developing acute lung injury, which predicts substantial mortality rates. While the correlation between acute lung injury and spinal cord injury has been found in the clinical setting, the field lacks an animal model to interrogate the fundamental biology of this relationship. To begin to address this gap in knowledge, we performed an experimental cervical spinal cord injury (N = 18) alongside sham injury (N = 3) and naïve animals (N = 15) to assess lung injury …

The Role Of The Kcc2 In Substance Use And Abuse: A Systematic Review [Protocol], Alfred Amendolara, Steven Salazar, Chad Thompson, Hyrum Wright, Andrew Payne

Annual Research Symposium

This poster presents the protocol for an ongoing systematic review investigating the role of potassium chloride co-transporter 2 (KCC2) in substance use, abuse, and addiction.

A Systematic Review: Toxoplasma Gondii Infection And Drugs Of Abuse, Amani Sastry

Annual Research Symposium

No abstract provided.

Appearance Of Two Distinct Clusters Of Glucose Dysregulation In Chronic Intractable Migraine, Roshni Jogin, Kaitlyn Mcfarland, Aparna Naik, Tanner Williford, Matthew Conway, Amar Paul, John A. Kriak, David W. Sant, Kyle B. Bills

Annual Research Symposium

No abstract provided.

Probing Amyloid-Beta Protein Structure And Dynamics With A Selective Antibody, Shikha Grover

Dissertations

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder. The AD brain is characterized by significant neuronal loss and accumulation of insoluble fibrillar amyloid-β protein (Aβ) plaques and tau protein neurofibrillary tangles in the brain. However, over the last decade, many studies have shown that the neurodegenerative effect of Aβ may in fact be caused by various soluble oligomeric forms as opposed to the insoluble fibrils. Furthermore, the data suggest that a pre-fibrillar aggregated form, termed protofibrils, mediates direct neurotoxicity, and triggers a robust neuroinflammatory response.

Antibodies targeting the various conformation of Aβ are important therapeutic agents to prevent the progression …

Examining The Effect Of A Substituted Carbamate Positive Allosteric Modulator On (Alpha4)3(Beta2)2 And (Alpha4)2(Beta2)3 Nicotinic Acetylcholine Receptors, Josue Gaona, Musharaf Mohiuddin, Ayman K. Hamouda

School of Medicine Student Publications and Presentations

The α4β2 nicotinic acetylcholine receptors (nAChR) are the most abundant nAChR subtypes in the brain and exist in two distinct isoforms: (α4)2(β2)3 nAChR, the high sensitivity (HS) isoform, and (α4)3(β2)2 nAChR, the low sensitivity (LS) isoform. Given the pathophysiological and pharmacological importance of these brain receptors, there are ongoing efforts to develop pharmacophores that selectively potentiate α4β2 nAChRs (positive allosteric modulators, PAMs). PAMs selective to the α4β2 nAChRs would be beneficial for neuropsychiatric conditions such as nicotine addiction and Alzheimer’s disease. A chemical synthesis and high throughput screens at Amgen laboratories have identified a series of compounds that preferentially potentiate …

Antibody-Dependent Enhancement Activity Of A Plant-Made Vaccine Against West Nile Virus, Amber M. Paul, Haiyan Sun, Dhiraj Acharya, Huafang Lai, Junyun He, Fengwei Bai, Qiang Chen

Publications

West Nile virus (WNV) causes annual outbreaks globally and is the leading cause of mosquito-borne disease in Unite States. In the absence of licensed therapeutics, there is an urgent need to develop effective and safe human vaccines against WNV. One of the major safety concerns for WNV vaccine development is the risk of increasing infection by related flaviviruses in vaccinated subjects via antibody-dependent enhancement of infection (ADE). Herein, we report the development of a plant-based vaccine candidate that provides protective immunity against a lethal WNV challenge mice, while minimizes the risk of ADE for infection by Zika (ZIKV) and dengue …

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, …

The Role Of Schwann Cells In Nerve Injury: Forskolin-Mediated Camp Activation Upregulates Tnfα Expression Despite Nf-Κb Downregulation In Lps-Treated Schwann Cells, Caitlyn E. Henry, Angela L. Asirvatham Ph.D.

Student Research Poster Presentations 2023

Although Schwann cells are known to play a role in axonal regeneration following nerve injury and inflammation, the exact mechanism is unknown. This study explores two potential mechanisms: the NF-κB and cAMP pathways. The NF-κB pathway produces cytokines, such as TNFα, to regulate inflammation, whereas the cAMP pathway is anti-inflammatory and regulates Schwann cell proliferation via AKAP95 and cyclin D3. Although it is well-known that NF-κB and cAMP are involved in inflammation, not much is known regarding the effects of forskolin-mediated cAMP activation on LPS-mediated NF-κB activation in Schwann cells. In this study, RT4-D6P2T immortalized rat Schwann cells were treated …

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 …

Effects Of Hiv-1 Tat And Opiates On Gene Regulation Of Oligodendrocyte Lineage Cells: Identification Of Myrf As A Novel Target, Kelly M. Flounlacker

Theses and Dissertations

HIV-associated neurocognitive disorders remain pervasive even with increased efficacy/use of antiretroviral therapies. Opioid use/abuse among HIV+ individuals is documented to exacerbate deficits. White matter (WM) alterations (myelin pallor, volume/structural) detected by diffusion tensor imaging, are common observations in HIV+ individuals. Using transgenic mice expressing HIV-1 Tat, we examined effects of 2-6 weeks of Tat/morphine exposure on WM using genomic/biochemical methods. RNA sequencing of striatal tissue after 2-weeks revealed robust changes in mRNAs associated with oligodendrocyte populations/myelin integrity, including Transferrin, Ndrg1, and myelin regulatory factor (Myrf/Mrf), an oligodendrocyte-specific transcription factor involved in differentiation/maturation. Immunoblots conducted after 6-weeks exposure in …

Expression Of Htyr In Drosophila As A Novel Model Of Parkinson’S Disease, Madeleine Callan

Scripps Senior Theses

Parkinson’s disease is a debilitating and often deadly neurodegenerative disease affecting a growing and large population. Its etiology has long remained elusive, and because no other organisms have Parkinsonian-like diseases, it is difficult to study PD using model organisms. Neuromelanin (NM), an insoluble melanin synthesized in the dopaminergic synthesis pathway in DA neurons, has recently been implicated in PD as a major causal factor. At high levels in DA lysosomes, it functions as a proteostatic pathway inhibitor–blocking dopaminergic neurons from breaking down harmful molecules until the lysosomes eventually degenerate as well as triggering autophagy, inflammation, and total neurodegeneration. Recently, neuromelanin …

Interactions Between Hiv And Opioids On Antiretroviral Accumulation, The Blood Brain Barrier, And The Inflammatory Response In The Brain., Kara Rademeyer

Theses and Dissertations

The complex mechanisms related to HIV infection, neurodegeneration, and chronic neuroinflammation collectively describe neuroHIV (Hauser et al. 2007; Chang et al. 2014; Smith et al. 2014). Specifically, opioid abuse, poor penetration of antiretroviral (ARV) drugs, chronic inflammation and neuronal injury/degeneration are all implicated in neuroHIV (Fantuzzi et al. 2003; Letendre et al. 2004; Verani et al. 2005; Duncan and Sattentau 2011; Hong and Banks 2015; Simoes and Justino 2015; Olivier et al. 2018; Murphy et al. 2019; Osborne et al. 2020). For the first time, we demonstrate that morphine, fentanyl, and methadone in vivo alter the brain accumulation of ARVs, …

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 …

Investigating Visinin-Like Protein 1 And Ubiquitinated Visinin-Like Protein 1 As Mild Traumatic Brain Injury Biomarkers, Yueming Wu

Theses and Dissertations--Chemistry

Traumatic brain injury (TBI) continues to be a significant cause of morbidity and mortality worldwide. Despite significant progress in understanding the complex pathophysiology of TBI, the underlying mechanisms remain poorly understood. The primary brain damage is acute and irreversible. However, secondary brain injuries often develop gradually over months to years, creating an opportunity for critical therapeutic interventions. In the past decade, research on TBI biomarkers has seen significant progress. This progress has been driven by the diverse nature of TBI pathologies and the challenges they present for evaluation, management, and prognosis. TBI biomarker proteins resulting from axonal, neuronal, or glial …

The Effects Of Age On Working Memory Capacity And Neural Function, Jasmin P. Joshi

CMC Senior Theses

Do age-related differences in working memory capacities predict specific neural responses? Theories of working memory (WM) suggest that there are different types of WM processes that are associated with specific neural networks and WM declines with age. Event-related potentials (ERPs) evoked by certain tasks are also associated with specific cognitive functions. This study investigates whether specific types of working memory capacities are related to corresponding neural indices of attention and context updating (P3; visual oddball task) or semantic (N400; word-pair paradigm task) processes. In addition, it examines whether age affects this relationship. Younger adults (n=30; ages 18-23) and older adults …

Brain Glycogen – Beyond Energy Storage In Glycogen Storage Diseases, Kia H. Markussen

Theses and Dissertations--Molecular and Cellular Biochemistry

Glycogen is a carbohydrate molecule that is traditionally viewed as a convenient and easily accessible energy storage form of glucose. However,emerging evidence supports the role of glycogen as more than a glucose storage form. During the last 20 years, glycogen has been shown to play pivotal roles in learning and memory, signaling events, viscosity, protein glycosylation, and be acritical hallmark in devastating diseases. Not only, does glycogen play a role as an energy substrate and critical metabolite during energy deprivation, glycogen is central for neurotransmitter homeostasis, tumor initiation, and ontributes to proper protein glycosylation in the brain. In this work, …

Visualization And Characterization Of The Immunological Synapse Between Chlorotoxin Chimeric Antigen (Cltx-Car) Redirected T Cells And Targeted Glioblastoma Tumors, Arianna Livi

CMC Senior Theses

Chimeric Antigen Receptor T (CAR-T) cells have demonstrated anti-tumor activity against aggressive and invasive cancers such as glioblastoma (GBM); however, clinical response rates remain low in clinical trial studies. Tumor heterogeneity and tumor microenvironment conditions pose significant challenges for treatment of GBM, thus continuous optimization of CAR-T cell therapies and identification of novel, widely expressed, and highly specific GBM antigens are vital to better patient outcomes. A newly developed CAR-T cell construct incorporating chlorotoxin (CLTX) as the targeting domain exhibited broad GBM-targeting capabilities and elicited potent cytotoxic effects during preclinical studies and is currently being tested in a phase I …

Selective Gsk3b Overexpression In Medial Prefrontal Cortex Camkiia Cells Produces Sex-Specific Changes In Ethanol Self-Administration, Anxiety-Like Behavior, And Working Memory, Sam Gottlieb, Zachary Tatom, Michael F. Miles

Graduate Research Posters

Background: Glycogen synthase kinase 3 beta (Gsk3b) is central in a gene network regulated by ethanol in mouse medial prefrontal cortex (mPFC). GSK3B abundance/activity modulations regulate ethanol consumption, suggesting GSK3B could be a target in treating alcohol use disorder. However, the critical cell type in this ethanol response is not yet known, nor have sex differences in GSK3B modulations been fully investigated. Here we report results of GSK3B overexpression selectively in CamKIIa⁺ mPFC cells on multiple behaviors.

Methods: Mice underwent stereotaxic injections to overexpress GSK3B in mPFC CamKIIa⁺ cells or control virus (n=4-6/sex/virus). We assayed working …

Heat Shock Protein 90 (Hsp90) System In Health And Disease., Daniella Munezero

Graduate Theses, Dissertations, and Problem Reports (ETD)

Cells rely on heat shock proteins (HSP) to facilitate and regulate the folding of the substrate proteins into their native state, and degradation if misfolding cannot be prevented. HSP90, a member of the HSP family, is a potential target for treatment of cancer and neurodegenerative diseases. Unfortunately, several clinical trials for cancer treatment have been discontinued due to cell toxicity accompanying HSP90 inhibition. HSP90 has four distinct but structurally similar paralogs. HSP90 inhibitors target all the paralogs despite increasing proof of functional differences among the paralogs. Understanding the in vivo function of HSP90 and the role played by each paralog …

Glyphosate And Dopaminergic Neurotoxicity: Herbicide Impacts On Parkinson's Disease Development, Lojy Hozyen

Undergraduate Research Posters

Nearly one million individuals in the United States are living with Parkinson’s disease (PD). In the past two decades, the death rate from PD has risen by about 63 percent in the United States. Major findings have been made in the past five years about the potential impact of glyphosate (N-(phosphonomethyl) glycine) exposure on the onset of PD symptoms. The purpose of this meta-analysis is to provide a compiled update on the chemical and biological alterations that glyphosate imposes on the human brain. A meta-analysis was conducted to create a quantitative estimate of the connection between PD and glyphosate. Findings …

Unraveling The Consequence Of Adult Onset Sulfatide Depletion: Its Implications In Myelin And Axonal Heath In The Context Of Neurodegenerative Disease, Elizabeth Dustin

Theses and Dissertations

Multiple Sclerosis is an immune mediated disease of the CNS. MS is diagnosed through detection of demyelinated regions. However, recent studies demonstrate that Normal Appearing White Matter (NAWM) contains substantial pathology. One such pathology observed in the NAWM is the reduction of sulfatide. The proper stoichiometry of lipids in myelin acts to maintain rapid conduction velocity, provide trophic support to the neuron, and protect the axon from degeneration. We previously characterized a mouse lacking sulfatide’s synthesizing enzyme, CST through constitutive gene disruption and demonstrate that sulfide is required for proper stability of the myelin sheath. However, since MS is typically …

The Impact Of Hiv-1 Tat And Morphine On Spatial Distribution Of Drugs In The Brain., Austin M. Jones

Theses and Dissertations

Despite combination antiretroviral therapy effectively suppressing HIV within the periphery, the central nervous system (CNS) remains affected by the virus. Approximately half of people living with HIV will experience HIV-associated neurocognitive disorders (HAND) or neuroHIV. Concurrent opioid use exacerbates neuroHIV by promoting neuroinflammation, viral replication, and potentially altering the antiretroviral concentrations within the brain.

Using a transgenic mouse that expresses the HIV-1 Tat protein, we examined the effects of Tat and morphine on antiretroviral accumulation and distribution and the effects of Tat on morphine accumulation within the brain using infrared matrix-assisted laser desorption electrospray ionization with mass spectrometry imaging (IR-MALDESI-MSI). …

Mechanistic Insight Into Traumatic Brain Injury Induced Neuronal Membrane Disruption: Cathepsin B Relocalization And A Neun Negative Cortical Neuron Subpopulation, Martina L. Hernandez

Theses and Dissertations

Traumatic brain injury (TBI) is a mechanical insult to the head that leads to brain damage and, in turn, causes long-term sensory, motor, cognitive, and affective dysfunction. Diffuse pathologies seen following such injury are associated with these life-altering outcomes that impact the daily lives of TBI survivors. The diffuse pathology that this body of work focuses on is neuronal membrane disruption; it is characterized by increased permeability of the neuron’s plasma membrane. Moreover, our lab had previously found that membrane disruption is exacerbated with intracranial pressure (ICP) elevation. We set out to measure the duration of membrane disruption following injury …

The Role Of Parkin In Mitochondrial Dna, Eliezer Lichter

Theses & Dissertations

Mitochondria are at the center of biological phenomena such as aging and diseases, especially neurodegenerative diseases. While the discovery of mitochondria only came approximately 200 years after the cell was discovered, a lot of progress has been made since. The mitochondrial genome encodes proteins vital for mitochondrial function. These proteins are only a subset of the proteins present in mitochondria; the rest are nuclear encoded. The nucleus also encodes cytosolic proteins vital for mitochondrial maintenance. One of these is Parkin, an E3 ubiquitin ligase that ubiquitinates mitochondrial proteins as mitochondria become depolarized. Its activity has been shown to be involved …

Metoprolol Disrupts Sterol Biosynthesis Through Inhibition Of 7-Dehydrocholesterol Reductase (Dhcr7), Luke B. Allen

Theses & Dissertations

Cholesterol is essential for life. It is particularly important in the brain as it relies on de novo synthesis of cholesterol following the formation of the blood brain barrier (BBB). As such, disrupting sterol biosynthesis during neurodevelopment can have devastating outcomes. The most common post-lanosterol sterol biosynthesis disorder, Smith-Lemli-Opitz Syndrome, arises from a faulty DHCR7 enzyme. DHCR7 has also been shown to be inhibited by several psychotropic medications. Here we assess six beta-blockers and their effects on sterol biosynthesis in vitro. Two beta-blockers, metoprolol and nebivolol strongly inhibit DHCR7 in four separate in vitro models of both mouse and …