Life Sciences Commons^™

Role Of Transforming Growth Factor (Tgf) – Β Signaling In Craniofacial Development, Malignancies And Regeneration, Jingpeng Liu

Theses & Dissertations

The transforming growth factor (TGF) – β signaling pathway regulates a diversity of fundamental cellular processes such as cell growth and proliferation, cell differentiation, migration, apoptosis and other biological functions, both during embryogenesis and in adult tissue homeostasis. TGF-β is known to play a critical role in palatal development as in TGF-β knockout murine models, TGF-β deficiency causes cleft palate, a common craniofacial deformity in humans due to the abnormality of growth, elevation or fusion of the two palatal shelves. In order to investigate the mechanisms of how TGF-β regulates palatogenesis, we generated TGF-β3 knockout (-/-) murine models, performed systematic …

Effects Of Gm-Csf On Dendritic Cells And Regulatory T Cells In Parkinson’S Disease Patients And Models Of Parkinson’S Disease, Charles Schutt

Theses & Dissertations

Parkinson’s disease (PD) is the most common neurodegenerative movement disorder. Pathologically, loss of nigrostriatal neurons and dopamine released by these neurons are responsible for PD motor symptoms. During PD, activation of resident microglia and infiltrating lymphocytes leads to progressive neuroinflammation and reduction in the number and function of regulatory immune cells. Neuroinflammation contributes to progressive neurodegeneration and declining motor function. Reducing neuroinflammation is the target for novel PD therapeutics. Our goal is to increase the number and function of regulatory T cells (Tregs) in PD patients to decrease neuroinflammation and reduce PD symptoms. One potential therapy is granulocyte-macrophage colony stimulating …

The Role Of Yes-Associated Protein 1 In Ovarian Physiology And Pathology, Xiangmin Lv

Theses & Dissertations

Ovarian granulosa cells are the major somatic components of the ovarian follicle. Proper proliferation and differentiation of ovarian granulosa cells are essential for successful follicle development. Accumulating evidence indicates that the Hippo-YAP signaling pathway plays critical roles in both development and tumorigenesis of several organs. The present study aims to investigate the role of Yes-associated protein 1 (YAP) in ovarian granulosa cell proliferation, differentiation, and malignant transformation. At first, we found that nuclear YAP (active) was highly expressed in proliferative granulosa cells, whereas cytoplasmic YAP (inactive) was detected mainly in terminally-differentiated luteal cells. Further studies suggested that endogenous YAP activity …

Novel Therapeutic Approaches For Juvenile Neuronal Ceroid Lipofuscinosis (Cln3), Megan Elizabeth Bosch

Theses & Dissertations

Juvenile Neuronal Ceroid Lipofuscinosis (JNCL) is a lysosomal storage disease caused by autosomal recessive mutations in CLN3. Neuronal loss is thought to occur via glutamate excitotoxicity; however, little is known about neuron-astrocyte glutamate regulation in JNCL. We discovered that Cln3^Δex7/8 astrocytes have significantly lower basal spontaneous Ca²⁺ oscillations and decreased responses to glutamate, indicating a disrupted signaling network. Cln3^Δex7/8 astrocytes also displayed significantly lower basal mitochondrial respiration and ATP production, suggesting impaired metabolic functions. Concurrent with diminished astrocyte metabolism and Ca²⁺ signaling, Cln3^Δex7/8 neurons were hyper-responsive to glutamate stimulation. These studies suggest that CLN3 …

Focus: A Graph Approach For Data-Mining And Domain-Specific Assembly Of Next Generation Sequencing Data, Julia Sommer

Theses & Dissertations

Next Generation Sequencing (NGS) has emerged as a key technology leading to revolutionary breakthroughs in numerous biomedical research areas. These technologies produce millions to billions of short DNA reads that represent a small fraction of the original target DNA sequence. These short reads contain little information individually but are produced at a high coverage of the original sequence such that many reads overlap. Overlap relationships allow for the reads to be linearly ordered and merged by computational programs called assemblers into long stretches of contiguous sequence called contigs that can be used for research applications. Although the assembly of the …

Defining The Role Of Neuropilin-2 In Macrophages: Implications In Tumor Associated Macrophages In Pancreatic Cancer, Sohini Roy

Theses & Dissertations

Macrophages are extremely heterogeneous and highly plastic hematopoietic cells that reside in all tissues and act as a bridge between the innate and adaptive arms of the immune responses. Besides, they undertake a wide array of housekeeping functions like, clearance of cellular debris that arise due to regular turnover in tissues, iron homeostasis, immune surveillance as well as tissue repair processes post inflammation. They are also causally associated with several clinical conditions, including cancer where the infiltration of macrophages contribute to disease progression, metastasis and therapy resistance, and thereby poor clinical outcome.

Neuropilins (NRPs) are non-tyrosine kinase cell surface glycoproteins …

Organizational Effects Of Defeminizing Toxicants: Lessons Learned From An Environmental Sentinel Organism, The Fathead Minnow., Jonathan Ali

Theses & Dissertations

Endocrine disrupting compounds (EDCs) are chemicals that interfere with hormone function and are increasingly detected in aquatic environments, where they elicit adverse effects from exposed organisms. The toxicological effects of EDCs can be described as either activational (reversible) or organizational (irreversible), where the latter are associated with adverse outcomes in reproductive performance of adult fish. However, few studies have investigated the organizational impacts of anti-estrogenic or “defeminizing” EDCs, e.g. agrichemicals or pharmacological agents, in an environmentally-relevant or “sentinel” species. The objective of this study was to investigate the impacts of early-life EDC-initiated changes in estrogenic gene expression on organizational effects …

Transcriptome Profiling Of Cleft Palate Intgf-Beta3 Knockout Mice Alleles: Rna-Seq Analysis Of Tgf-Beta3 Mice, Kelsey White

Theses & Dissertations

Background: Orofacial clefts are the most common craniofacial birth defect with a complex, combinatorial etiology. Tgf-b3 regulates palatal fusion in mice; Tgf-b3 knockout mice have cleft palate (CP) lacking other major deformities. The genes downstream of Tgf-b3 during palatogenesis remain largely unexplored. Our objective was to analyze the global transcriptome changes and their contribution to CP and identify novel Tgf-b3 associated genes involved in formation of CP. We used RNA-sequencing to analyze and compare the whole transcriptome of Tgf-b3 alleles during palatal growth and fusion in mice.

Results: …

Perturbing Anti-Apoptotic Proteins To Develop Novel Cancer Therapies, Jacob Contreras

Theses & Dissertations

The apoptotic pathway involves a tightly regulated network of proteins which respond to various stimuli. Previous studies have indicated Mcl-1 and Bcl-xL are intimately involved in determining cell fate, and if both are concurrently neutralized, it activates the apoptotic pathway. The inactivation of Bcl-xL and Mcl-1 as a mechanism to trigger the intrinsic apoptotic response can be used as a platform to develop therapeutic strategies to target cancer cells. The apoptotic pathway is largely dysregulated and often leads to therapy resistance in cancer cells. Although direct inhibitors of Bcl-xL have been developed and have advanced to clinical trials, development of …

A Role For Δ-Catenin In Synaptic Regulation, Li Yuan

Theses & Dissertations

The cadherin-catenin complex regulates cell-cell adhesion and signal transduction in epithelial cells. It is becoming increasingly evident that components of the complex regulate various aspects of neuronal architecture and function. δ-catenin is a cytosolic component of the cadherin-catenin complex and is predominantly expressed in the central nervous system. Loss of CTNND2, which encodes δ-catenin, is associated with intellectual disability and mutations in CTNND2 have been identified in autism, suggesting that δ-catenin is a critical component of the molecular machinery underlying neural circuit function. We have previously demonstrated that δ-catenin regulates multiple aspects of synaptic and dendritic development, including dendritic …

Comparative Molecular Characterization Of Typical And Exceptional Responders In Glioblastoma, Kristin Wipfler

Theses & Dissertations

Glioblastoma (GBM) is the most common and the deadliest type of primary brain tumor, with a median survival time of only 15 months despite aggressive treatment. Although most patients have an extremely poor prognosis, a small number of patients survive far beyond the median survival time. Investigation of these “exceptional responders” has sparked a great deal of interest and is becoming an important focus in the field of cancer research. To investigate the molecular differences between typical and exceptional responders in GBM, comparative analyses of copy number, methylation, gene expression, miRNA expression, and protein expression data sets from The Cancer …

Identifying The Role Of Janus Kinase 1 In Mammary Gland Development And Breast Cancer, Barbara Swenson

Theses & Dissertations

The development of the postnatal mammary gland is tightly controlled by peptide hormones and cytokines. The signaling of these extracellular ligands through their corresponding receptors rely on Janus Kinases (JAKs) that activate downstream Signal Transducers and Activators of Transcription (STATs). The JAK/STAT signaling pathway is crucial for processes such as growth, proliferation, and cell survival of the epithelial tissue, but also for the breakdown and remodeling of the mammary gland via IL-6 class inflammatory cytokines (e.g. LIF and OSM). JAK1 and JAK2, which are expressed in the mammary gland, are thought to have redundant functions. However, our previous studies demonstrated …

Role Of Ezrin In Colorectal Cancer Cell Survival Regulation, Premila Leiphrakpam

Theses & Dissertations

Colorectal cancer (CRC) is the second most common cause of cancer related deaths in the United States, mainly due to metastasis to the distant organ sites. However, the molecular basis of CRC metastasis is poorly understood. Therefore, identification and characterization of novel potential anti-cancer therapeutic targets CRC is of urgent need. Utilizing a 2D-DIGE proteomics approach ezrin was identified as a protein that is differentially expressed between primary colon tumors xenografts, orthotopically implanted in athymic nude mice, and corresponding and liver metastatic deposits. Ezrin, a cytoskeletal protein belonging to the ezrin–radixin–moesin (ERM) family plays important roles in cell motility, invasion …

Evaluation Of Aminopyrazole Analogs As Cyclin-Dependent Kinase Inhibitors For Colorectal Cancer Therapy, Caroline Robb

Theses & Dissertations

Colorectal cancer (CRC) remains one of the leading causes of cancer related deaths in the United States. Currently, there are limited therapeutic options for CRC patients, none of which focus on the cell signaling mechanisms controlled by members of the cyclin dependent kinase (CDK) family. CDK5 has been implicated in a variety of cancers, and most recently as a tumor promoter in CRC.

As such, we evaluated a compound developed by Pfizer, CP-668863 (a.k.a. 20-223), that inhibits CDK5 in neurodegenerative disorders. In our CRC xenograft model, 20-223 reduced tumor growth and tumor weight, indicating its value as a potential anti-CRC …

Metabolic Reprogramming Of Pancreatic Ductal Adenocarcinoma Cells In Response To Chronic Low Ph Stress, Jaime Abrego

Theses & Dissertations

Pancreatic ductal adenocarcinoma (PDAC) is among the most lethal of all cancers with a 5-year survival rate of only 8.2%. This is because PDAC is diagnosed in its advanced stages and is characterized by radio and chemotherapy resistance. Aggressiveness of PDAC tumors is attributed to its high metabolic phenotype, which is characterized by increased glycolysis rate and lactate secretion, while oxidative metabolism is reduced. These metabolic features are required to fulfill the biosynthetic demands of proliferating PDAC cells. However, this increase in metabolic activity results in acidification of the extracellular space because the dense fibrotic stroma of PDAC tumors limits …

Dopamine Levels In The Brain Of Rat Models Of Human Rheumatoid Arthritis, Amelia Stinson

Theses & Dissertations

Research Focus. Rheumatoid arthritis (RA) is a chronic, debilitating, autoimmune disease that causes the destruction of bone tissue and the articular structures of joints. At least 30% of RA patient populations have cognitive impairment. Acidic dopamine (DA) is the principal neuroimmunotransmitter that links the central nervous system and peripheral nervous system together. The aim of the present study was to determine the levels of DA and its two acidic metabolites: 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in arthritic induced rats, and whether their levels vary across four different parts of the brain: amygdala (AMG), front cerebral cortex (CX), hippocampus …

An Investigation Of The Levels Of Pro-Inflammation Cytokines In The Brain Of Autoimmune Lewis Rats, Han Yang

Theses & Dissertations

Rheumatoid arthritis (RA) is a chronic inflammatory joint disease, which can cause cartilage and bone damage, as well as disability. A reported symptom of RA includes tissue inflammation disease and cognitive dysfunction. This study aimed to compare the concentration of selected cytokines in the cerebral cortex, hippocampus, hypothalamus, amygdala, and cerebellum of Lewis rats. Age and sex-matched Lewis rats were separated into two groups: control and adjuvant-induced RA. Twenty-eight days after the adjuvant injection, groups were sacrificed and brains dissected using the stereotaxic atlas of Paximos and Watson as a guide. Pro-inflammatory cytokines IL-1β, IL-6, and IL-23, plus the anti-inflammatory …

Redirection Of The Immune Response To Staphylococcus Aureus Biofilm Infection, Anna G. Staudacher

Theses & Dissertations

Staphylococcus aureus (S. aureus) is a leading cause of community- and healthcare-associated infections and has a propensity to form biofilms. Biofilm infections are recalcitrant to host immune-mediated clearance as well as antibiotics, making them exceptionally difficult to eradicate. The biofilm environment has been shown to skew the host immune response towards an anti-inflammatory phenotype, characterized by alternatively activated macrophages, recruitment of myeloid-derived suppressor cells (MDSCs), and minimal neutrophil and T cell infiltrates. Our laboratory has attempted to redirect the host immune response towards one that would favor bacterial clearance by employing strategies to augment pro-inflammatory mechanisms. One such …

Development Of C5ar-Targeted Nanoparticles For Delivery Of Vaccines, Shailendra Bharadwaj Tallapaka Venkata Sesha

Theses & Dissertations

Since the early attempts of Benjamin Jesty at inducing immunity against smallpox and the pioneering work of Edward Jenner, vaccination has been, and continues to remain, the principal method of protection from diseases. However, most of the successful vaccines have been against pathogens that do not have major mechanisms to evade the immune system. So far, many life-threatening diseases like hepatitis C, HIV infection, malaria etc., have been resistant to existing vaccination strategies. Thus, there is an urgent need to develop new vaccination strategies that can generate long-lived protective immunity against such pathogens.

The purpose of this thesis is to …

Molecular Mechanisms Of C-Terminal Eps15 Homology Domain Containing (Ehd) Protein Function, Kriti Bahl

Theses & Dissertations

Endocytic trafficking is not only an essential process for the maintenance of cellular homeostasis but also plays a vital role in regulating diverse cellular processes such as signaling, migration and cell division. The C-terminal Eps 15 Homology Domain proteins (EHD1-4) play pivotal roles in regulating distinct steps of endocytic trafficking. Among the EHDs, EHD2 is disparate both in terms of sequence homology (70%) and its subcellular localization at the caveolae. The crystal structure of EHD2 has been solved and it contains an unstructured loop consisting of two proline-phenylalanine (PF) motifs: KPFRKLNPF. However, the other paralogs EHD1, …

Inflammasome Activation By Methamphetamine Potentiates Lipopolysaccharide Stimulation Of Il-1Β Production In Microglia, Enquan Xu

Theses & Dissertations

Methamphetamine (Meth) is a psychostimulant drug that is widely abused all around the world. The administration of Meth causes a strong instant euphoria effect, and long-term of abuse is correlative of drug-dependence and neurotoxicity. The neuroimaging studies demonstrated that the long-term abuse of Meth is associated with the reduction of the dopamine transporter (DAT) and vesicular monoamine transporter (VMAT2) in the striatum. Neuroinflammation is well-accepted as an important mechanism underlying the Meth-induced neurotoxicity. The over-activated microglia were found both in Meth human abusers and animal models.

NACHT, LRR, and PYD domains-containing protein 3 (NLRP3) inflammasome is the most predominant Nod-like …

Pattern Recognition Receptors, Immune Proteins, And Nf-Κb Signaling Regulate Behaviors Associated With Aging Phenotypes, Nicholas W. Dekorver

Theses & Dissertations

The aging process is accompanied by functional impairments, including reduced locomotor function, fragmentation of active states, and alterations in energy balance. Our lab has demonstrated that immune proteins are increased in specific regions of the mouse brain that correlate with strain specific deficits. These immune proteins include toll-like receptors (Tlr), class I major histocompatibility complex proteins (MHC I), and complement proteins. There is an increasing appreciation for the role of immune proteins in neurodevelopment; however, their involvement in age-associated deficits is poorly understood. Here, we present data demonstrating that 1) activation of a specific immune receptor (Tlr2) leads to changes …

Added Sugar Consumption Among College Students, Maram Murad

Theses & Dissertations

Added sugar consumption has been increasing in all age groups in the United States and worldwide, with the greatest increase in young adults. College-age years are a critical period in the young adult's life where many habits develop, including nutrition and food choices. An understanding of college-age students’ attitudes and behaviors toward added sugar consumption might help predict added sugar consumption within this population. This was a quantitative study of traditional-aged college students' added sugar consumption through a convenience sample at a private university in San Antonio, TX. A survey was administrated to undergraduate students at different classes. Subjects were …

The Role Of Semaphorin 5a In Pancreatic Cancer Progression And Metastasis, Sugandha Saxena Dr.

Theses & Dissertations

Pancreatic cancer (PC) is an aggressive disease with an overall 5-year survival rate of less than 7%, statistics that have not changed in almost five decades. Metastasis is one of the leading causes of mortality in PC. Accumulating evidence suggests that axon guidance molecules, such as semaphorins, are involved in cancer progression, invasion, and metastasis. Recent genomic characterization of pancreatic ductal adenocarcinoma revealed aberration in axon guidance pathway genes as well. Previous reports from our laboratory have identified one such molecule Semaphorin5A (SEMA5A) as a putative cell adhesion molecule which is involved in organ-specific homing during PC metastasis. My dissertation …

Requirement Of Ehd Family Of Endocytic Recycling Regulators For T-Cell Functions, Fany M. Iseka

Theses & Dissertations

T-cells use the endocytic pathway for key cell biological functions, including receptor turn-over and maintenance of the immunological synapse. Some of the established players include the Rab GTPases, SNARE complex proteins, and others which in non-T-cell systems function together with Eps15 Homology Domain-containing (EHD) proteins. To date, the role of the EHD protein family in T-cell function remains unexplored. We generated conditional EHD1/3/4 knockout mice using CD4-Cre and crossed these with mice bearing a myelin oligodendrocyte glycoprotein (MOG)-specific TCR transgene. We found that CD4⁺ T-cells from these mice exhibited a reduced antigen-driven cell proliferation and IL-2 secretion in vitro. …

Development Of Neurotensin-Based Radiopharmaceuticals For Neurotensin-Receptor-1-Positive Tumors Targeting, Yinnong Jia

Theses & Dissertations

The neurotensin receptor 1 (NTR1) is overexpressed in many cancers, due to its role as a growth pathway. These NTR1-positive cancers include pancreatic, colon, prostate and breast cancers. In the radiopharmaceutical field, the overexpression of NTR1 in cancer has prompted the development of NTR1-targeted diagnostics and therapeutics. The neurotensin (NT) peptide exhibits low nanomolar affinity for NTR1 and has been the paradigm for NTR1-targeted agents. Since the 1980’s, radiolabeled NT analogs have been developed and evaluated for targeting NTR1-positive cancers. Since native NT is rapidly degraded in vivo by a variety of peptidases, a tremendous amount of effort has been …

Identification Of Important Regulators Of Colon Cancer Tumorigenesis By Functional Screening, Haowei Yi

Theses & Dissertations

TGFβ signaling is an important regulator in colon cancer. miRNAs regulate TGFβ signaling at multiple levels. In this study, through a functional screening, we identified miR-487b-3p and miR-656-3p, which modulate TGFβ effect in colon cancer cells. Further studies revealed that GRM3 and VGLUT3 are their respective targets.

GRM3, a Metabotropic glutamate receptor in glutamatergic pathway is significantly upregulated in majority of human colonic adenocarcinomas tested and colon cancer cell lines. Knockdown of GRM3 expression or inhibition of GRM3 activation in colon cancer cells reduces cell survival and anchorage-independent growth in vitro and inhibits tumor growth in vivo. Mechanistically, GRM3 …

Basal And Experience Dependent Ampar And Synapse Dynamics: Alterations In A Mouse Model Of Fragile X Syndrome, Anand Suresh

Theses & Dissertations

Dendritic spines are the principal sites of excitatory synapses in the neurons of mammalian central nervous system. Spine are plastic, undergoing structural and functional changes under basal and experience dependent conditions. Spine properties are altered in a number of neurodevelopmental disorders including the Fragile X syndrome (FXS) which is the most common inherited form of intellectual disability. The structural reorganization of dendritic spines is thought to be associated with synaptic plasticity mechanisms that are deficient in FXS. A number of synaptic plasticity mechanisms involve modulation of synaptic strength via insertion or removal of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPAR). However, the link …

Epigenetic Modifications Of Human Placenta Associated With Preterm Birth, Drissa Toure

Theses & Dissertations

Preterm birth is a complex multifactorial process. Despite the well-known role of the placenta in supporting the fetal development and maternal-fetal tolerance, the placental epigenetic modifications and preterm birth (PTB) remains poorly understood and under investigated. Various maternal and environment factors can influence epigenetic programming during fetal development to affect the functioning and structures of organs, including the placenta, which can lead to adverse pregnancy outcomes, including PTB. The understanding of the placental epigenetic alterations and maternal determinants associated with PTB are apparently indispensable for the development of actual diagnosis and methods of prevention and treatment of premature labor. The …

Aberrant Glycosylation In Pancreatic Cancer Progression, Seema Chugh

Theses & Dissertations

Aberrant changes in O-glycosylation patterns underlie pancreatic ductal adenocarcinoma (PDAC) progression and metastasis. Glycosylation is a post-translational modification in which carbohydrate moieties are attached to the protein substrate. My dissertation is focused on mucin-type O-glycosylation, which is the predominant form of O-glycosylation and is regulated by a myriad of glycosyltransferases.

PDAC is one of the most lethal diseases and the mechanistic involvement of aberrant O-glycosylation in its progression and metastasis is unknown. The aberrant glycosylation refers to the appearance of unusual carbohydrate structures such as truncated carbohydrate antigens, often referred to as tumor-associated carbohydrate antigens.

In this dissertation, my goal …