Pharmacology, Toxicology and Environmental Health Commons^™

Characterization Of A Pathological Tau Point Mutation, E342v, Implicated In Frontotemporal Dementia, Liam Clancy

Graduate College Dissertations and Theses

Frontotemporal Dementia (FTD) is classified as a Tauopathy, a group of heterogenous neurodegenerative disorders characterized by the abnormal functioning of a microtubule associated protein (MAP), Tau. Microtubules, an integral cytoskeletal component in neurons, are thought to be stabilized by Tau. In disease states such as FTD, a reduction in binding affinity of Tau for the microtubule is believed to lead to intraneural Tau deposition and aggregation, which subsequently causes microtubule instability. Consequently, neuronal health is compromised and an array of brain functions decline creating the symptomology seen in FTD. However, it is now known that Tau has a myriad of …

Runx1 Loss Leads To An Epithelial To Mesenchymal Transition In Breast Cancer By Regulating Target Gene Expression., Dorcas Lohese

Graduate College Dissertations and Theses

Breast cancer is the second leading cause of cancer death among women in the United States. Due to the various advancements in treatment, the five-year survival rate is greater than 90% among women with non-metastatic breast cancer. However, among patients with metastatic breast cancer, the five-year survival rate quickly drops to 22%. Recognizing early signs of metastasis is essential for targeting cancer before it disseminates. The epithelial-to-mesenchymal transition (EMT) is hypothesized to be a vital process for large-scale cell movement by disrupting cell-cell adhesion, allowing metastatic breast cancer cells to become more migratory. The progression of breast cancer EMT involves …

The Evaluation Of The Prokinetic Action Of A Luminally Restricted 5-Ht4 Receptor Agonist In Mice, Emma Schoeling

Graduate College Dissertations and Theses

Serotonin (5-HT) is a neurotransmitter mainly produced in the enteric nervous system (ENS) of the gastrointestinal (GI) system. Serotonin has widespread function throughout the body including regulating mood, cognition, sleep, sex, and appetite. In the context of the gut, the monoamine modulates vasodilation, mucus secretion, pain, and peristaltic reflexes for motility. The 5-HT4 receptor is expressed on enteric epithelial cells and nerve terminals in the intestinal mucosa. The agonists available to act on these receptors are a favorable target to promote epithelial healing, recovery from colitis or constipation, and epithelial cell proliferation. The non-absorbable, luminally restricted, 5-HT4R agonist (5HT4-LA1; Takeda …

Exploring The Mechanisms Of Pkg1-Α Activation By Synthetic Peptides, Connor Cronin

Graduate College Dissertations and Theses

Cyclic GMP-dependent protein kinases (PKG’s) are essential signaling macromolecules which play a pivotal role in vascular physiology and smooth muscle tone regulation. As principle downstream effectors of the secondary messenger cyclic 3’, 5’-guanosine-monophosphate (cGMP), PKG isoforms are expressed in high levels in all types of smooth muscle cells. The broad range of cellular functions effected by PKG include platelet aggregation, hypertrophy, apoptosis, neuronal plasticity, gene expression, differentiation, vasorelaxation, vascular remodeling, calcium homeostasis, and cardiac function. Recently, a newly characterized helical switch domain within the alpha isoform of PKG (PKG1-α) has led to the development of S1.1, a novel cGMP-independent peptide …

Thyroid Hormone Receptor Beta Inhibits Pi3k Signaling And Glycogen Metabolism In Anaplastic Thyroid Cancer, Cole Davidson

Graduate College Dissertations and Theses

Thyroid cancer is the most common endocrine malignancy, and the global incidence has increased rapidly over the past few decades. While differentiated thyroid cancers often respond to standard therapies, there are no durable long-term treatment options for anaplastic thyroid cancer (ATC). The limited treatment options highlight a need for a deeper understanding of the molecular signaling in these aggressive tumors for development of more effective therapies.Non-steroidal nuclear receptors, such as thyroid hormone receptors (TRs), are an emerging class of therapeutic targets and tumor suppressors in thyroid and other cancers.Loss of expression of the tumor suppressor thyroid hormone receptor beta (TRβ) …

Genetic Ablation Of Kir2.1 Channels And Its Effects On Micturition In Conscious Mice, Ryan Thomas Shields

Graduate College Dissertations and Theses

Detrusor muscle overactivity in the bladder wall is the hallmark symptom of overactive bladder syndrome and the principal target of therapy that seeks to reduce incontinence and urinary urgency. However, these interventions typically fail to alleviate long-term detrusor overactivity and simply mask the underlying pathology while also potentially introducing undesirable side effects that disrupt quality of life. One alternative mechanism driving of overactive bladder is attributed to ischemia within the bladder, which is subject to enormous swings in pressure and tension on its vasculature restricting blood flow. This observation, coupled with the fact that healthy vascular tissue within the bladder …

Functional Characterization Of Leptomeningeal Anastomoses In Physiological Condition And Chronic Hypertension, Zhaojin Li

Graduate College Dissertations and Theses

Stroke is the second leading cause of death worldwide and the leading cause of devastating disability. Leptomeningeal anastomoses (LMAs) are small distal anastomotic vessels, also known as pial collaterals in the brain. These vessels redirect blood flow during an occlusion and are important for stroke treatment and outcome. Hypertension, a major risk factor for stroke, is associated with limited amounts of salvageable tissue, greater perfusion deficit and worse stroke outcome. Angiotensin II (Ang II), generated from angiotensin I by angiotensin converting enzyme (ACE), is importantly involved in the pathogenesis of hypertension. Despite the important clinical implications, functions of LMAs in …

Structure Activity Relationship Studies Of An Anticryptosporidial Drug, Kirtika Chatri

Graduate College Dissertations and Theses

Cryptosporidium is an apicomplexan parasite responsible for waterborne outbreaks of diarrheal disease worldwide. There are two species of Cryptosporidium that are important enteric pathogens for humans. The disease, Cryptosporidiosis, is a major cause of childhood diarrhea and an important factor in childhood malnutrition and also a high rate of death (Sparks et al., 2015). It is also more frequent and severe in malnourished children under 3 years of age and immune-compromised individuals, such as AIDS and transplant patients. A common treatment which has greatly reduced diarrhea-associated mortality is oral rehydration therapy; however, enteric infections still persist (Guerrant, DeBoer, Moore, Scharf, …

Network And Cellular Effects Of The Mu Opioid Receptor In Cortical Interneurons, Adrian Dutkiewicz

Graduate College Dissertations and Theses

The µ opioid receptor (µOR) exerts a powerful excitatory effect in cortical circuits and cultured neurons by promoting glutamatergic activity after binding endogenous or exogenous opioids. While most research indicates that the receptor does this by decreasing activity or output of GABAergic interneurons that inhibit glutamate-releasing Pyramidal Neurons, other experiments suggest that the µOR directly upregulates excitatory Pyramidal Neurons instead. Thus, the cellular target of cortical opioid agonists remains unclear, and the µOR’s net excitatory mechanisms are not fully understood. Consequently, utilizing electrophysiology to detect µOR responses to the specific agonist [D-Ala2, N-Me-Phe4, Gly5-ol]-Enkephalin (DAMGO) has yielded incomplete information on …

Analysis Of Intracellular Calcium Events In Hypothalamic Neurons, Samantha Kolowrat

Graduate College Dissertations and Theses

The paraventricular nucleus of the hypothalamus (PVN) plays a critical role in regulating the hypothalamic-pituitary-adrenal (HPA) axis, sympathetic activity, cardiovascular system and stress responses.1,2 This brain region is primarily controlled by GABA and glutamate inputs from the peri-PVN region.3 Two significant modulators of these GABA-glutamate systems are Angiotensin II (Ang II) and brain derived neurotrophic factor (BDNF). It has been postulated that BDNF and Ang II signaling rely on each other via cross-activation of their receptors and by activation of the non-selective cation channel, the transient receptor channel type C3 (TRPC3).This thesis aims to study changes in intracellular calcium levels …

Designer Biologics Composed Of Hepatocyte Growth Factor, Fibroblast Growth Factor 2 And Immunoglobulin G For Treatment Of Acute Myocardial Infarction, Benjamin Liebman

Graduate College Dissertations and Theses

ABSTRACT Coronary artery disease leading to myocardial infarction (a.k.a. MI, heart attack) is one of the leading causes of death globally. Each year an estimated 605,000 Americans suffer a heart attack, which equates to one MI every 40 seconds. As such, MI represents one of the largest health burdens to society. The current standard of care is revascularization therapy achieved by fibrinolytics and Percutaneous Coronary Intervention (PCI); both of which re-open occluded proximal arteries to restore blood flow to the affected areas. Despite revascularization therapy, 30-50% of patients exhibit a form of reperfusion injury termed “no/low-reflow” in which the blood …

Exploring Tsrna Function In Aggressive Breast Cancer Cell Models, Caroline Adams

Graduate College Dissertations and Theses

Abstract

Breast cancer is highly prevalent in the United States with an estimated 260,000 women diagnosed with invasive breast cancer in 2018 alone. There is a growing need to identify the molecular drivers of metastatic breast cancer as the molecular mechanisms responsible for the transition from normal mammary epithelial cells to aggressive cancer cells remain poorly understood. Understanding this transition may reveal a therapeutic target for aggressive breast cancer. Small, noncoding RNAs (ncRNA), such as microRNAs (miRNAs), have recently been discovered to promote initiation, progression, and metastasis of breast cancer. Similar in size to miRNAs, tRNA-derived small RNAs (tsRNAs) are …

Pharmacological Inhibition Of Hif-1 Alpha And Its Effects On Dendritic Cell Metabolic Reprogramming, Warrick Sahene

Graduate College Dissertations and Theses

Dendritic cells (DCs) are antigen presenting cells (APCs), a subtype of immune cells that present cellular information to T cells in the immune system. Hypoxia inducible factor 1 alpha (HIF-1 alpha) is an important transcription factor that facilitates dendritic cell metabolism by upregulating glycolysis in activated DCs. In this project, we examined the effects of HIF-1 alpha inhibition on metabolic processes of dendritic cells. Using techniques such as flow cytometry, western blotting, and extracellular flux analyzers, we used a selective inhibitor of HIF-1 alpha to test the hypothesis that HIF-1 alpha promotes glycolytic dependent processes such as glucose production, survival, …

Tsrna Involvement In Promoting Breast Cancer Phenotypes, Stephanie Scalia

Graduate College Dissertations and Theses

The overall 5-year survival rate for woman diagnosed with breast cancer has increased significantly over the last 20 years. However, prognosis for women with stage IV, metastatic disease remains very poor. Women diagnosed with stage 0-III breast cancer have above an 85% chance of survival over a 5-year period while women diagnosed with stage IV breast cancer have a 5-year survival of less than 30%. A better understanding of the molecular mechanisms driving aggressive breast cancer is essential for the potential discovery of more targeted therapies to increase the survival rates for women diagnosed with stage IV breast cancer.

Previous …

Finding Brain Predictors Of Psychostimulant Medication Use In Adhd Using Machine Learning, Zoe Irene Hulce

Graduate College Dissertations and Theses

Psychostimulant medication is the first line of treatment for Attention deficit/hyperactivity disorder (ADHD). Despite the prevalence of ADHD, there is a lack of understanding of the underlying neurophysiological mechanisms of the disorder and its pharmacological treatments. Existing neuroimaging research shows some consistent structural differences in ADHD, but it can be difficult to discern what is relevant. Machine learning algorithms present a novel way of analyzing a large amount of data by making predictions based on pattern detection.

The present study applied an elastic-net logistic machine learning model to structural magnetic resonance imaging (sMRI) data from the Adolescent Brain Cognitive Development …

Understanding The Role Of Androgen Receptor Signaling In Modulating P38-Alpha Mitogen-Activated Protein Kinase In Experimental Autoimmune Encephalomyelitis, Grace Kathryn Voorhees

Graduate College Dissertations and Theses

Multiple Sclerosis (MS) is an inflammatory autoimmune disease of the central nervous system, characterized by axonal demyelination and multifocal inflammation. Like many autoimmune diseases, it is a sexually dimorphic disease, being 3-4 times more common in females than in males. p38α MAP kinase (MAPK) has an integral role in modulating inflammatory processes in autoimmunity. Conditionally ablating p38α MAPK in myeloid cells in B6 mice shows a sex difference in the animal model of MS, experimental autoimmune encephalomyelitis (EAE). In the absence of sex hormones, this sex difference was reversed, suggesting a role for sex hormones in modulating p38α MAPK signaling …

The Metabotropic Glutamate Receptor Mglur1 Regulates The Voltage-Gated Potassium Channel Kv1.2 Through Agonist-Dependent And Agonist-Independent Mechanisms, Sharath Chandra Madasu

Graduate College Dissertations and Theses

The voltage gated potassium channel Kv1.2 plays a key role in the central nervous system and mutations in Kv1.2 cause neurological disorders such as epilepsies and ataxias. In the cerebellum, regulation of Kv1.2 is coupled to learning and memory. We have previously shown that blocking Kv1.2 by infusing its specific inhibitor tityustoxin-kα (TsTX) into the lobulus simplex of the cerebellum facilitates eyeblink conditioning (EBC) and that EBC itself modulates Kv1.2 surface expression in cerebellar interneurons. The metabotropic glutamate receptor mGluR1 is required for EBC although the molecular mechanisms are not fully understood. Here we show that infusion of the mGluR1 …

The Effects Of 5-Ht4 Receptor Agonists On Interleukin-10 Knockout Mice, Quentin Mylie

Graduate College Dissertations and Theses

Recent studies have demonstrated that activation of the 5-HT4 receptors in the colonic mucosa can have healing and protective actions in experimental models of colitis. These actions include increased mucus secretion, increased epithelial proliferation, and enhanced epithelial migration. Since these studies involved chemically induced models of colitis, the current investigation was conducted to test whether a protective action of 5-HT4 receptor stimulation could be detected in Interleukin-10 knockout (IL-10 KO), which develop colitis spontaneously due to the absence of the anti-inflammatory cytokine, interleukin-10.

Upon weaning, the IL-10 knockout mice were separated into two groups: an agonist group and a vehicle …

Activation Of Trpv1 Channel Contributes To Serotonin-Induced Constriction Of Mouse Facial Artery, Bolu Zhou

Graduate College Dissertations and Theses

Tight regulation of cephalic blood circulation is critical under normal physiological conditions, and dysregulation of blood flow to the head occurs in pathophysiological situations such as stroke and migraine headache. The facial artery is an extracranial artery which is one of branches from the external carotid artery territory and its extracranial position indicates its importance in regulating head hemodynamics. Transient receptor potential vanniloid type 1 (TRPV1) is a cation channel permeable to Ca2+ and Na+. Intracellular Ca2+ increase causes vasoconstriction. A previous study indicated the presence of TRPV1 in smooth muscle cells in the facial artery. Protein kinase C (PKC) …

Changes In Threonyl-Trna Synthetase Expression And Secretion In Response To Endoplasmic Reticulum Stress By Monensin In Ovarian Cancer Cells, Jared Louis Hammer

Graduate College Dissertations and Theses

Aminoacyl-tRNA synthetases (ARS) are a family of enzymes that catalyze the charging of amino acids to their cognate tRNA in an aminoacylation reaction. Many members of this family have been found to have secondary functions independent of their primary aminoacylation function. Threonyl-tRNA synthetase (TARS), the ARS responsible for charging tRNA with threonine, is secreted from endothelial cells in response to both vascular endothelial growth factor (VEGF) and tumor necrosis factor-α (TNF-α), and stimulates angiogenesis and cell migration. Here we show a novel experimental approach for studying TARS secretion, and for observing the role of intracellular TARS in the endoplasmic reticulum …

The Effects Of Hypothalamic Brain-Derived Neurotrophic Factor On Catecholaminergic Regulation Of Cardiovascular Function., Nicholas Christopher Cruickshank

Graduate College Dissertations and Theses

Considerable evidence supports the claim that a hyperactive sympathetic nervous system (SNS) is involved in most cases of human hypertension, and therefore a more thorough understanding of the central regulation of the SNS may help elucidate novel therapeutic options. The PVN is a key region in SNS regulation of blood pressure (BP) and heart rate (HR). Stimulation of the parvocellular PVN neurons has been shown to enhance sympathetic outflow and thereby increase BP. Brain-derived neurotrophic factor (BDNF), a modulator of neuronal activity is upregulated in the paraventricular nucleus of the hypothalamus (PVN) in response to several hypertensive stimuli such as …

Natural Selection And Genetic Variation In A Promising Chagas Disease Drug Target: Trypanosoma Cruzi Trans-Sialidase, Joseph P. Gallant

Graduate College Dissertations and Theses

Rational drug design is a powerful method in which new and innovative therapeutics can be designed based on knowledge of the biological target aiming to provide more efficacious and responsible therapeutics. Understanding aspects of the targeted biological agent is important to optimize drug design and preemptively design to slow or avoid drug resistance. Chagas disease, an endemic disease for South and Central America and Mexico is caused by Trypanosoma cruzi, a protozoan parasite known to consist of six separate genetic clusters or DTUs (discrete typing units). Chagas disease therapeutics are problematic and a call for new therapeutics is widespread. Many …

Assessment Of A Function For Threonyl-Trna Synthetase In Angiogenesis In A Mouse Ovarian Cancer Model, Peibin Wo

Graduate College Dissertations and Theses

Despite the high mortality rate of ovarian cancer, there are few selective biomarkers that detect its progression and none have become successful targets for therapy. A complex microenvironment that promotes angiogenesis, reduces immune responses and alters the integrity of the surrounding matrix is involved through the biology of ovarian cancer. Previous studies done by our lab and collaborators indicated that extracellular threonyl-tRNA synthetase (TARS) is a pro-angiogenic mediator of the ovarian tumor microenvironment, which is secreted in response to inflammatory signals, and actively promotes angiogenesis. In order to better understand the mechanisms underlying the angiogenic effects of TARS in ovarian …

New Approaches To Heterocycle Synthesis: A Greener Route To Structurally Complex Protonated Azomethine Imines, And Their Use In 1,3-Dipolar Cycloadditions, Ram Chandra Dhakal

Graduate College Dissertations and Theses

1-Aza-2-azoniaallene salts are reactive intermediates that undergo [3+2] cycloaddition with many different types of multiple bonds. For the past several years, the Brewer group has studied the reactivity of these intermediates in intramolecular reactions, and have discovered that these cationic heteroallenes can react through a variety of other, mechanistically distinct, pathways to give different classes of nitrogen heterocycles. For example, prior work in the Brewer group revealed that 1-aza-2-azoniaallene salts could react in an intramolecular [4+2] cycloaddition reaction to give protonated azomethine imine salts containing a 1,2,3,4-tetrahydrocinnoline scaffold. Further study of the scope and limitations of this Diels-Alder-like reaction are …

Transdermal Testosterone For Menopause-Related Hyposexual Desire Disorder: Current Guidelines And Provider Perceptions, Knowledge, And Practice, Kelly Christine White

Graduate College Dissertations and Theses

Hypoactive sexual desire or low libido in women are collectively referred to as hypoactive sexual desire disorder (HSDD). HSDD is estimated to occur in 10% to 15% of adult women. HSDD is likely the most common female sexual dysfunction (FSD) in menopausal women. The hallmark of the diagnosis is personal distress and interpersonal difficulties resulting from low sex drive. Most women will not seek help for this problem. Studies have suggested that primary care providers and gynecologic healthcare providers report not feeling qualified to treat patients with sexual dysfunction, especially HSDD. Testosterone, specifically transdermal testosterone, has been suggested to play …

Regulation Of Middle Meningeal Artery Diameter By Pacap And Atp-Sensitive Potassium Channels, Arsalan Urrab Syed

Graduate College Dissertations and Theses

Migraine is one of the most prevalent contributors to the global burden of mental and neurological disorders. It is a complex episodic condition that presents as intense recurrent unilateral headaches lasting hours to days that can be accompanied by nausea, photophobia, phonophobia and other neurological symptoms. The causes of migraine appear multifactorial and are not fully understood. However, activation of the trigeminovascular system and sphenopalatine parasympathetic neurons and the resulting vasodilation of meningeal arteries have been associated with the development of migraine pain. Recently, the neurotransmitter and neurotrophic peptide pituitary adenylate cyclase activating polypeptide (PACAP) has been implicated in this …

Traumatic Brain Injury Causes Endothelial Dysfunction In Mesenteric Arteries 24 Hrs After Injury, Ivette Ariela Nunez

Graduate College Dissertations and Theses

Traumatic brain injury (TBI) is the most frequent cause of death in children and young adults in the United States. Besides emergency neurosurgical procedures, there are few medical treatment options to improve recovery in people who have experienced a TBI. Management of patients who survive TBI is complicated by both central nervous system and peripheral systemic effects. The pathophysiology of systemic inflammation and coagulopathy following TBI has been attributed to trauma-induced endothelial cell dysfunction; however, there is little knowledge of the mechanisms by which trauma might impact the functions of the vascular endothelium at sites remote from the injury. The …

Ubiquitin Ligase Trim32 And Chloride-Sensitive Wnk1 As Regulators Of Potassium Channels In The Brain, Eugene Miler Cilento

Graduate College Dissertations and Theses

The voltage-gated potassium channel Kv1.2 impacts membrane potential and therefore excitability of neurons. Expression of Kv1.2 at the plasma membrane (PM) is critical for channel function, and altering Kv1.2 at the PM is one way to affect membrane excitability. Such is the case in the cerebellum, a portion of the brain with dense Kv1.2 expression, where modulation of Kv1.2 at the PM can impact electrical activity of neurons and ultimately cerebellum-dependent learning. Modulation of Kv1.2 at the PM can occur through endocytic trafficking of the channel; however mechanisms behind this process in the brain remain to be defined.

The goal …

Characterization Of A Non-Canonical Function For Threonyl-Trna Synthetase In Angiogenesis, Adam Christopher Mirando

Graduate College Dissertations and Theses

In addition to its canonical role in aminoacylation, threonyl-tRNA synthetase (TARS) possesses pro-angiogenic activity that is susceptible to the TARS-specific antibiotic borrelidin. However, the therapeutic benefit of borrelidin is offset by its strong toxicity to living cells. The removal of a single methylene group from the parent borrelidin generates BC194, a modified compound with significantly reduced toxicity but comparable anti-angiogenic potential. Biochemical analyses revealed that the difference in toxicities was due to borrelidin's stimulation of amino acid starvation at ten-fold lower concentrations than BC194. However, both compounds were found to inhibit in vitro and in vivo models of angiogenesis at …

Mechanoregulation Of Leading Edge Pka Activity During Ovarian Cancer Cell Migration, Andrew J. Mckenzie

Graduate College Dissertations and Theses

Ovarian cancer is the deadliest of all the gynecologic cancers and is known for its clinically occult and asymptomatic dissemination. Most ovarian malignancies are diagnosed in the late stages of the disease and the high rate of morbidity is thought to be due, in part, to the highly metastatic nature of ovarian carcinomas. Cancer metastasis relies on the ability of cells to migrate away from primary tumors and invade into target tissues. Though the processes are distinct, cancer cell invasion relies on the underlying migration machinery to invade target tissues.

Cell migration requires the coordinated effort of numerous spatially-regulated signaling …