Medicine and Health Sciences Commons^™

Autotaxin In Central Nervous System Development And Disease, Natalie A. Wheeler

Theses and Dissertations

During development, oligodendrocytes (OLGs), the myelinating cells of the central nervous system (CNS), undergo a stepwise progression during which OLG progenitors, specified from neural stem/progenitor cells, differentiate into fully mature myelinating OLGs. This progression along the OLG lineage is characterized by well-synchronized changes in morphology and gene expression patterns. The studies presented in this dissertation identified the extracellular factor Autotaxin (ATX) as a novel upstream signal modulating HDAC1/2 activity and gene expression in cells of the OLG lineage. Using the zebrafish as an in vivo model system, as well as rodent primary OLG cultures, this functional property of ATX was …

The Role Of Epidermal Stem/Progenitor-Like Cells In Hpv-Mediated Pre-Neoplastic Transformation, Yvon L. Woappi

Theses and Dissertations

The role of epidermal basal stem cells in dysplasia is a matter of great interest in the human papillomavirus (HPV)-driven cancers. To assess the relationship between “stemness” and HPV-mediated transformation, we made use of 3-D suspension culture and fluorescence activated cell sorting (FACS) to purify stem/progenitor-like cells from primary normal human keratinocyte (NHKc) cultures. We found that NHKc cells derived from multicellular keratinocyte spheroids were enriched for a basal subpopulation of epidermal stem-like cells, that could be maintained for prolonged time in culture and used to conduct transfection experiments with full-length HPV16 DNA. Thus, by using these stem cell enrichment …

Regulation Of Chronic And Acute Inflammatory Disease By Microrna And Microbiota, Pegah Mehrpouya-Bahrami

Theses and Dissertations

Inflammation is implicated in cancer development, degenerative diseases, allergies as well as artherosecelorsis. Dysregulated immune responses lead to chronic inflammation and tissue damage. Finding the ways to terminate inflammatory responses when no longer needed, demands further investigation. Herein, we investigated the modulation of acute and chronic inflammatory disease models by inducing antiinflammatory state. Acute inflammatory model was induced with SEB, an enterotoxin produced by a ubiquitous Gram-positive coccus, Staphylococcus aureus (S. aureus), which exerts profound toxic effects on the immune system, which leads to the cytokine storm and adverse immune response. SEB is the main cause of nosocomial infections, acute …

Linking Obesity & Breast Cancer: Role Of Monocyte Chemoattractant Protein-1 And High Fat Diet-Induced Inflammation On Mammary Tumorigenesis, Taryn L. Cranford

Theses and Dissertations

More than two-thirds of the adult population in the United States is classified as overweight or obese. In order to fully comprehend this rapidly increasing dilemma, further understanding of the complex phenomena that are involved with obesity and its many comorbidities is necessary. Chronic inflammation represents a distinctive, recurrent feature of obesity and has been associated with an increased risk of breast cancer. Monocyte chemoattractant protein 1 is a crucial component of the inflammatory process and represents a potential therapeutic treatment target, not only in obesity but also in breast cancer. Using a monocyte chemoattractant protein deficient model, we examined …

The Effect Of Arsenic On Type 2 Diabetes And Inflammation, Kayla Penta

Theses and Dissertations

Arsenic, a ubiquitous environmental contaminant, has been shown to cause a number of health effects. At high concentrations the inorganic form is a well-known toxin, but at lower concentrations the effects range from various cancers, to cardiovascular disease and type 2 diabetes. At higher concentrations of arsenic (500- 1000μg/L) there have been epidemiological studies conducted demonstrating an increased risk in the development of type 2 diabetes with this exposure. At lower levels of arsenic exposure (<500 μg/L) the epidemiological results are inconclusive. Arsenic is also an immunotoxicant, meaning that it will cause changes in the immune response. The changes in the immune response will vary depending on a number of variables, including amount of arsenic exposure, forms of exposure and route of exposure. We wanted to determine if arsenic could modulate the immune system, and if this change could lead to an increase in susceptibility to type 2 diabetes development. We chose to examine this in C57BL/6 and db/+ mice – two non-susceptible strains. After 8 weeks (4 weeks old to 12 weeks old) of low dose inorganic arsenic exposure (50 μg/kg or 500 μg/kg) we evaluated changes in body composition, glucose tolerance and immune response. We saw that there were differences based on sex, genotype and treatment group present after the 8-week treatment period in body composition, while there were minimal changes in glucose tolerance. Finally, the immune response showed great variability depending on sex, genotype and treatment group. This project has demonstrated that while we are trying to compare differences in in vivo and epidemiological studies to find a link between arsenic and type 2 diabetes, there may be deeper levels of complications based on individual variability to arsenic exposure.

Differences In Resting-State Functional Connectivity Of Chronic Migraine, With And Without Medication Overuse Headache, And The Effectiveness Of Sphenopalatine Ganglion Block As A Treatment For Repairing Dysfunctional Connectivity., Kaitlin Krebs

Theses and Dissertations

Chronic Migraine (CM) is a debilitating neurological condition that occurs when the migraine frequency progresses to a chronic state of more than 15 headache days per month. The overuse of analgesic medication (MOH) is one of the most prominent risk factor of this chronification and little is known about why it is a cause. The repetitive inhibition of the Sphenopalatine Ganglion is one promising treatment that is used to treat chronic migraine. The purpose of this study is to determine if a specific pattern of disruption is present for chronic migraine, both with and without medication overuse headache, and if …

N-Methyl 4-Methyl Amphetamine N-Alkyl Chain Extension Differentially Affects Ion Flux At The Human Dopamine And Norepinephrine Transporters, Alan C. Harris Jr.

Theses and Dissertations

Amphetamine (AMPH) and its derivatives embody a remarkable breadth of pharmacology. These molecules exert their effects, both therapeutic and pathological, at the human monoamine transporters, which tune synaptic dynamics by evacuating monoamine neuromodulators from the synapse subsequent to neuronal impulses. These transporters are electrogenic, and the transporter-mediated current can be correlated to a surrogate measure of the change in membrane voltage: Ca⁺⁺ currents from co-transfected L-type Ca⁺⁺ channels. The present work makes use of this assay, with which it is possible to derive pharmacodynamic metrics from both substrates and inhibitors. This work presents data on a heretofore-unstudied class …

Power Analysis In Applied Linear Regression For Cell Type-Specific Differential Expression Detection, Edmund Glass

Theses and Dissertations

The goal of many human disease-oriented studies is to detect molecular mechanisms different between healthy controls and patients. Yet, commonly used gene expression measurements from any tissues suffer from variability of cell composition. This variability hinders the detection of differentially expressed genes and is often ignored. However, this variability may actually be advantageous, as heterogeneous gene expression measurements coupled with cell counts may provide deeper insights into the gene expression differences on the cell type-specific level. Published computational methods use linear regression to estimate cell type-specific differential expression. Yet, they do not consider many artifacts hidden in high-dimensional gene expression …

Role Of Vav2 In Podocyte Inflammasome Activation And Glomerular Injury During Hyperhomocysteinemia, Sabena Conley

Theses and Dissertations

Hyperhomocysteinemia (hHcys) is a widely known pathogenic factor in the progression of end-stage renal disease (ESRD) and it is also associated with an increased risk for injurious cardiovascular pathologies during ESRD. HHcys is linked to the formation and activation of the NOD-like receptor protein 3 (NLRP3) inflammasome, characterized as a critical early mechanism initiating the inflammatory response. NADPH oxidase (NOX)-derived reactive oxygen species (ROS) mediate the activation of the NLRP3 inflammasome in podocytes in response to elevated levels of homocysteine (Hcys) in vitro and in vivo. However, it remains unknown how NLRP3 inflammasome activation is triggered by NOX. The …

Assembly And Regulation Of The Dream Complex, Jessica G. Felthousen

Theses and Dissertations

The DREAM complex assembles during G0/G1 when RB-like protein p130 recruits E2F4, DP1, and a core complex of five MuvB proteins to repress genes involved in cell cycle progression. In S-phase, the MuvB core dissociates from p130 and binds to BMYB transcription factor. Binding of the MuvB core to p130 requires phosphorylation of its subunit LIN52 at S28 residue by DYRK1A protein kinase. However, little is known about how the MuvB core interacts with p130 to form the DREAM complex, and how these interactions are manipulated throughout the cell cycle. In collaboration with Dr. Seth Rubin, we characterized the structural …

The Effects Of 7,8-Dihydroxyflavone On Hippocampal Neurogenesis Following Traumatic Brain Injury, Mary K. Wurzelmann

Theses and Dissertations

Following traumatic brain injury (TBI), the hippocampus is particularly vulnerable to damage, and BDNF, an endogenous neurotrophin that activates the TrkB receptor, has been shown to play a key role in the brain’s neuroprotective response. Activation of the TrkB signaling pathway by BDNF in the CNS promotes cell survival and aids in cell growth. However, due to its inability to cross the blood brain barrier (BBB), the therapeutic advantages of BDNF treatment following TBI are limited. 7,8-Dihydroxyflavone (7,8-DHF) is a flavonoid that mimics the effects of BDNF, is a potent TrkB receptor agonist, and can successfully cross the BBB. Our …

Determining The Effect Of Knocking Out Microrna-21 On Subsarcolemmal And Interfibrillar Mitochondria, Madhur Batra

Theses and Dissertations

Type 2 diabetes mellitus is a growing problem across the world and has significant pathological changes associated with it, including diabetic cardiomyopathy, wherein cardiac function is reduced. MicroRNA-21 has been shown to play a role in both the heart and diabetes so it was thought that knocking out miR-21 could have a protective effect on oxidative phosphorylation function in diabetic mice. Subsarcolemmal and interfibrillar mitochondria were isolated from adult male WT, miR-21 KO, db/db, and double knockout mice (db/db and miR-21 KO cross) and evaluated for function. Knocking out miR-21 in diabetic mice showed a restorative effect in Complex I …

Investigating The Molecular Etiologies Of Sporadic Als (Sals) Using Rna-Sequencing, David G. Brohawn

Theses and Dissertations

ALS is an often lethal disease involving degeneration of motor neurons in the brain and spinal cord. Current treatments only extend life by several months, and novel therapies are needed. We combined RNA-Sequencing, systems biology analyses, and molecular biology assays to elucidate sporadic ALS group-specific differences in postmortem cervical spinal sections (7 sALS and 8 control samples) that may be relevant to disease pathology. >55 million 2X150 RNA-sequencing reads per sample were generated and processed.

In Chapter 2, we used bioinformatics tools to identify nuclear differentially expressed genes (DEGs) between our two groups. Further, we used Weighted Gene Co-Expression Network …

The Mauc Gene Encodes A Versatile Signal Sequence And Redox Protein That Can Be Utilized In Native And Non-Native Protein Expression And Electron Trnasfer Systems, Brian Dow

Electronic Theses and Dissertations

The redox-active type 1 copper site of amicyanin is composed of a single copper ion that is coordinated by two histidines, a methionine, and a cysteine residue. This redox site has a potential of +265 mV at pH7.5. Over ten angstroms away from the copper site resides a tryptophan residue whose fluorescence is quenched by the copper. The effects of the tryptophan on the electron transfer (ET) properties were investigated by site-directed mutagenesis. Lessons learned about the hydrogen bonding network of amicyanin from the aforementioned study were attempted to be used as a model to increase the stability of another …

Role Of Klf8-Cxcr4 Signaling In Breast Cancer Metastasis, Debarati Mukherjee

Electronic Theses and Dissertations

Krüppel-like factor 8 (KLF8) has been strongly implicated in breast cancer metastasis. However, the underlying mechanisms remain largely unknown. In this study we report a novel signaling from KLF8 to C-X-C cytokine receptor type 4 (CXCR4) in breast cancer. Overexpression of KLF8 in MCF-10A cells induced CXCR4 expression at both mRNA and protein levels. This induction was well correlated with increased Boyden chamber migration, matrigel invasion and transendothelial migration (TEM) of the cells towards the ligand CXCL12. On the other hand, knockdown of KLF8 in MDA-MB-231 cells reduced CXCR4 expression associated with decreased cell migration, invasion and TEM towards CXCL12. …

Intracellular Ros Mediates Gas Plasma-Facilitated Cellular Transfection In 2d And 3d Cultures, Dehui Xu, Biqing Wang, Yujing Xu, Zeyu Chen, Qinjie Cui, Yanjie Yang, Hailan Chen, Michael G. Kong

Bioelectrics Publications

This study reports the potential of cold atmospheric plasma (CAP) as a versatile tool for delivering oligonucleotides into mammalian cells. Compared to lipofection and electroporation methods, plasma transfection showed a better uptake efficiency and less cell death in the transfection of oligonucleotides. We demonstrated that the level of extracellular aqueous reactive oxygen species (ROS) produced by gas plasma is correlated with the uptake efficiency and that this is achieved through an increase of intracellular ROS levels and the resulting increase in cell membrane permeability. This finding was supported by the use of ROS scavengers, which reduced CAP-based uptake efficiency. In …

An Analysis Of Plasticity In The Rat Respiratory System Following Cervical Spinal Cord Injury And The Application Of Nanotechnology To Induce Or Enhance Recovery Of Diaphragm Function, Janelle Lorien Walker

Wayne State University Dissertations

Second cervical segment spinal cord hemisection (C2Hx) results in ipsilateral hemidiaphragm paralysis. However, the intact latent crossed phrenic pathway can restore function spontaneously over time or immediately following drug administration.

WGA bound fluorochromes were administered to identify nuclei associated with diaphragm function in both the acute and chronic C2Hx models. WGA is unique in that it undergoes receptor mediated endocytosis and is transsynaptically transported across select physiologically active synapses. Comparison of labeling in the acutely injured to the chronically injured rat provided an anatomical map of spinal and supraspinal injury induced synaptic plasticity. The plasticity occurs over time in the …

A Few Notes On Nabokov's Childhood Entomology, Victor Fet

Biological Sciences Faculty Research

Nabokov's lepidoptery long posed a question: Was he an amateur or a professional entomologist? Today, it has been amply demonstrated that he was a professional. Kurt Johnson says, "For Nabokov, as with many, fascination with the big picture books of butterflies as a young child grew to concerted collecting as a youngster. As with many scientists, these impressions of youth become a driving life force."³ Nabokov started collecting butterflies in 1906, at age seven, and never ceased; he published his first book of poems ten years later, at age seventeen; his first research paper on butterflies, at age twenty; …

Modeling Early Stage Bone Regeneration With Biomimetic Electrospun Fibrinogen Nanofibers And Adipose-Derived Mesenchymal Stem Cells, Michael P. Francis, Yas M. Moghaddam-White, Patrick C. Sachs, Matthew J. Beckman, Stephen M. Chen, Gary L. Bowlin, Lynne W. Elmore, Shawn E. Holt

School of Medical Diagnostics & Translational Sciences Publications

The key events of the earliest stages of bone regeneration have been described in vivo although not yet modeled in an in vitro environment, where mechanistic cell-matrix-growth factor interactions can be more effectively studied. Here, we explore an early-stage bone regeneration model where the ability of electrospun fibrinogen (Fg) nanofibers to regulate osteoblastogenesis between distinct mesenchymal stem cells populations is assessed. Electrospun scaffolds of Fg, polydioxanone (PDO), and a Fg:PDO blend were seeded with adipose-derived mesenchymal stem cells (ASCs) and grown for 7-21 days in osteogenic differentiation media or control growth media. Scaffolds were analyzed weekly for histologic and molecular …

Genetic Enhancer Screen With Transition Zone Mutant Nphp-4 Reveals Novel Interactions With Mutation Affecting Intraflagellar Transport And Endocytic Pathways, Scott Henke

All ETDs from UAB

to suggest an association between log(CRP) and smoking, controlling for WC and race.

The Effect Of Proinflammatory Cytokines On Thioredoxin-Interacting Protein In Pancreatic Beta-Cells, Kyunghee Hong

All ETDs from UAB

Pro-inflammatory cytokines, such as Interleukin (IL)-1β, Tumor necrosis factors (TNF) α, and Interferon (IFN)γ, have been implicated as critical mediators of β-cell destruction in diabetes. In addition, although a combination of these three cytokines has been used to mimic the inflammatory conditions of type 1 diabetes in vitro, the mechanisms underlying the effect are not fully understood. Previously, we discovered Thioredoxin-interacting protein (TXNIP) as a key regulator of glucotoxicity-induced β-cell apoptosis and β-cell dysfunction, while deletion of TXNIP prevented type 1 (T1D) and type 2 diabetes (T2D). However, the effects of proinflammatory cytokines on the regulation of TXNIP have not …

The Matricellular Protein Ccn1 Potentiates Fibrogenic Responses To Lung Injury, Ashish Kurundkar

All ETDs from UAB

Normal wound healing is a well-coordinated reparative response to injury aimed at restoring the normal tissue function. The dynamic interactions between cells and ex-tracellular matrix (ECM) regulate and dictate the fate of tissue repair process. Fibrosis is a dysregulated wound healing with excessive deposition of ECM and loss of tissue func-tion. Idiopathic pulmonary fibrosis (IPF) is a chronic progressive fibrotic disease of lung with no cure. Matricellular proteins are non-structural matrix proteins which regulates the cellular functions by directly binding to cell surface integrins and/or indirectly modulating growth factor signaling. Matricellular proteins are emerging as critical mediators of tissue injury …

Leukemia Stem Cell Markers And Inv(16) In Acute Myeloid Leukemia, Jason Legrand

All ETDs from UAB

Although greater than 85% of inv(16) acute myeloid leukemia patients are able to achieve first complete remission after anthracycline- and cytarabine-based therapy, only about 60% of patients survive the disease long-term due to relapsed disease or treatment-related mortality. Multiple studies have shown that acute myeloid leukemia is composed of heterogeneous populations of leukemic clones that can exhibit a wide degree of genetic, epigenetic, and functional diversity, accounting for different outcomes in response to therapy. Genomic analysis of leukemic clones in paired diagnostic and relapse samples of acute myeloid leukemia has shown that all relapses stem from surviving leukemic or ancestral …

Regulation Of Breast Cancer Metastasis By Sin3 Chromatin Remodeling Complexes, Monica Jeanene Lewis

All ETDs from UAB

Metastasis continues to be the most difficult clinical challenge for breast cancer. Survival rates for patients with metastatic breast cancer have not significantly changed in the past 20 years. Therefore, we need a better understanding of the molecular mechanisms that regulate breast cancer metastasis to develop effective therapies. SIN3 chromatin remodeling complexes have been implicated in breast cancer progression. Mammalian cells have two paralogs of SIN3 (SIN3A and SIN3B) that are encoded by distinct genes and have unique functions during development. However, specific roles for SIN3A and SIN3B in breast cancer progression have not been characterized. To better understand how …

Analysis Of The Ciliary Genes Gas8 And Mks6 Reveal Conserved Roles In Cilia Motility And Transition Zone Function, Wesley Robert Lewis

All ETDs from UAB

Cilia are microtubule based cellular appendages that are present throughout the hierarchy of the animal kingdom. These appendages are utilized for a wide array of functions such as motility in single celled organisms to coordinating complex cellular signaling pathways in more complex organisms. Though these appendages are well conserved, the exact function of cilia in many cell types remains unknown. Recently, cilia are tied to a myriad of developmental diseases and diseases of adult homeostasis collectively referred to as ciliopathies. Dysfunction in cilia results in a wide array of phenotypes ranging from retinal degeneration to polydactyly, cystic kidney disease, and …

Development Of A Split Luciferase Complementation Assay To Investigate Growth Hormone Receptor/ Prolactin Receptor Homo-/ Hetero-Association, Ying Liu

All ETDs from UAB

Growth hormone receptor (GHR) and prolactin receptor (PRLR) are transmembrane glycoproteins cytokine receptors that are structurally homologous. Each can pre-homodimerize and ligand binding of each activates JAK2-STAT signaling pathways by inducing conformational change within the receptor homodimer. Human GHR can be activated by growth hormone (GH) while human PRLR can be activated by both GH and prolactin (PRL). We devised a split luciferase complementation assay, in which one receptor is fused to the N-terminal fragment of luciferase and the other receptor is fused to the C-terminal fragment of luciferase. When the two receptors approximate, luciferase activity (complementation) results. Using this …

Ribosomal Protein L12 (Rpl12) As A Novel Target In Cystic Fibrosis, Kathryn E. Oliver

All ETDs from UAB

Approximately 1,000 new cases of cystic fibrosis (CF) are diagnosed in the United States every year. The disease is caused by over 1,700 naturally occurring variants in the CF transmembrane conductance regulator (CFTR). Defects in the CFTR coding sequence contribute to variable disease severity in the patient population. The majority of individuals born with CF harbor at least one specific mutation in CFTR termed F508del. Clinical manifestations of CF include severe damage of multiple exocrine tissues, including the lungs, intestine, pancreas, reproductive and other organ systems. An overarching goal of our work is to identify cellular targets that contribute to …

Targeting The Tumor-Promoting Microenvironment With Inhibitors Of Pro-Hgf Activation, Benjamin Yaw Owusu

All ETDs from UAB

The tumor microenvironment plays a key role in tumor progression and therapeutic resistance. Hepatocyte growth factor (HGF), commonly expressed by cancer-associated fibroblasts, mediates signaling via its receptor, MET, and promotes survival, proliferation, migration and invasion of cancer cells. In addition, HGF dependence has emerged as a hallmark of therapeutic resistance. HGF is secreted as an inactive precursor, pro-HGF, which requires proteolytic cleavage and processing to form the mature, active HGF. This is the rate-limiting step in the HGF/MET signaling pathway and it is achieved by one of the serine proteases, matriptase, hepsin and HGF activator (HGFA). At Southern Research, we …

Reorganization Of The Golgi Apparatus During Human Cytomegalovirus Infection, George Michael Rebmann

All ETDs from UAB

Human cytomegalovirus (HCMV) is the largest and most structurally complex of all the herpesviruses. HCMV is an important human pathogen that results in significant morbidity and disease in immunocompromised individuals. The assembly of herpesviruses is complex and involves a nuclear and cytoplasmic phase. The nuclear events of capsid assembly and genome incorporation as well as nuclear egress are believed to be similar in all herpesviruses and as such, are more clearly defined then the cytoplasmic phase; including the process of tegument and envelope acquisition. Human Cytomegalovirus induces the reorganization of the cellular secretory pathway including the Golgi apparatus and membranes …

Cd4 Regulatory T Cells Augment Hiv-1 Expression Of Polarized M1 And M2 Monocyte Derived Macrophages, Tanya Robinson

All ETDs from UAB

Polarization of macrophages is critical for an effective host immune response against invading pathogens. However, the HIV-1 virus can alter the cytokine/chemokine profile of polarized macrophages which may ultimately lead to their increased susceptibility to viral infection. M1 monocyte-derived macrophages (MDM) have been shown to suppress CCR5-tropic HIV-1 replication, while M2 MDM promote it. We generated M1 (GM-CSF + IFN-γ + LPS) and M2 (M-CSF + IL-4) MDM with predicted phenotypes and exposed them to a CCR5 (R5) “highly macrophage-tropic” viral strain, HIV-1BaL. M2 MDM had notably higher levels of HIV-1 infection than M1 MDM. We also investigated R5 HIV-1 …