Medical Cell Biology Commons^™

Hepatocyte Peroxisome Biogenesis And Phytol-Induced Metabolic Stress In Liver Disease, William Galloway

Theses, Dissertations and Capstones

Hepatocyte peroxisomes are required for metabolism of phytol-derived branched-chain fatty acids through the ACOX2-SCPx beta-oxidation pathway. This study tests whether hepatocyte-specific deletion of PEX16 (Pex16^Alb-Cre), which eliminates peroxisome biogenesis, sensitizes the liver to phytol-induced injury. The Pex16^Alb-Cre mice and their normal control Pex16^fl/fl mice were fed the Lieber-DeCarli liquid with or without 0.1 percent phytol for eight weeks. Serum alanine aminotransferase (ALT) and liver index were measured. Liver sections were stained with hematoxylin and eosin and Masson’s trichrome. Immunoblot analysis of peroxisomal enzyme expression was also performed. Phytol had no effect in Pex16^fl/fl mice as …

Role Of Insulin-Like Growth Factor-1 Signaling In Diet-Enhanced Bone Elongation, Cassaundra A. White

Theses, Dissertations and Capstones

Childhood obesity has increased precipitously to the point that almost 20% of children between the ages of 2 and 19 have been diagnosed with obesity. While obesity is a complex metabolic disorder, one contributing factor is diet, particularly a diet high in fat. Among many problems associated with diet-induced obesity, the impact on skeletal health is often overlooked. In addition to increased stress on the skeleton due to excess weight, obesity also disrupts the endocrine and immune systems that, in turn, can secondarily alter skeletal growth. Obesity during the early years of childhood is particularly detrimental because the skeleton is …

Role Of Thymidine Phosphorylase In Type 2 Diabetes-Associated High-Risk Of Thrombosis, Adam Belcher

Theses, Dissertations and Capstones

Cardiovascular diseases (CVDs), such as ischemic heart disease and stroke, are the leading causes of death globally that disproportionally affects patients with type 2 diabetes mellitus (T2DM) at a 2-4-fold rate compared to non-diabetic patients. These CVDs result from a blood clot, also known as a thrombus, formed in arteries that can block blood flow resulting in tissue damage and death. Antiplatelet drugs, such as aspirin and clopidogrel, used to prevent thrombosis have been found to be less effective in diabetics and increase the risk of hemorrhagic events. The T2DM epidemic has made it imperative to find therapies that decrease …

Na/K-Atpase Alphα1 Regulates Adipogenesis Via Its Conserved Caveolin Binding Motif, Minqi Huang

Theses, Dissertations and Capstones

The Na/K-ATPase (NKA) was identified in 1957 by Dr. Jens C. Skou. It belongs to the P-type ATPase family, which can actively transport ions across cell membranes by using the energy from adenosine triphosphate (ATP) hydrolysis. During the second half of the 20th century, the molecular mechanism of the NKA catalytic cycle was clarified, and the isoform diversity of NKA in different species and organs was identified. The active ion transport through NKA generates cell membrane ion gradients and the electric potential. Hence, the enzymatic function of NKA is critical for cell viability as well as multiple physiological processes including …

The Epigenetic Effects Of Omega-3 Fatty Acids In Diffuse Large B-Cell Lymphoma, Tanner Jeffrey Bakhshi

Theses, Dissertations and Capstones

Diffuse large B-cell lymphoma (DLBCL) is the most common type of lymphoma. It is an aggressive cancer, with 50-70% of patients diagnosed at an advanced stage and 30-50% of patients not cured by chemoimmunotherapy. DLBCL is almost always caused by genetic damage sustained during the germinal center (GC) reaction. The mechanisms that govern the GC reaction bear a striking resemblance to those that drive DLBCL. Genomic studies have shown that some of its most common mutations occur in genes that encode epigenetic modifiers, including the lysine (histone) acetyltransferases CREBBP and p300. These mutations prevent the acetylation of multiple histone residues, …

Targeting Epigenetic Mechanisms In Endometriosis, Sarah Elizabeth Brunty

Theses, Dissertations and Capstones

Endometriosis is a complex and elusive gynecological disease in which the inner lining of the uterus grows in locations outside of the uterus and forms lesions. It is known to affect 1 in 9 women of reproductive age worldwide. Symptoms of endometriosis include severe pain, heavy periods, and infertility. While multiple theories of origin exist, none fully encompass all aspects of the disease, although all theories agree that this is an inflammation-driven disease. Due to this, many researchers are turning towards epigenetics to explain the initiation and progression of endometriosis. However, what is causing these epigenetic changes is still a …

Crippling Rapid Evolution Of Metastasis And Drug Resistance In A549 Non-Small Cell Lung Cancer Cells With The Clinically Relevant Hsp90 Inhibitor Auy922, Nickolas Anthony Bacon

Theses, Dissertations and Capstones

The ability for species to evolve new features in response to changing circumstances in order to survive and propagate is a ubiquitous observation on both the macroscopic and microscopic levels of living systems. It should be no surprise, then, that diseases such as cancer utilize their own forms of adaptation to perpetuate themselves when exposed to external threats. Indeed, concepts drawn from Darwinian evolution are now widely accepted to help explain certain aspects of carcinogenesis and malignant progression, the sum of which have come to be known as the theory of tumor evolution. Since metastasis and drug resistance are features …

Dysfunctional Mitochondrial Biogenesis: A Potential Underlying Cause For Metabolic Diseases, Caroline Ann Hunter

Theses, Dissertations and Capstones

Mitochondria are essential organelles that play crucial roles in many aspects of cellular homeostasis. More importantly, the mitochondria are home to the majority of the metabolic pathways within the cell and are responsible for producing most of the cell’s useable energy in the form of adenine triphosphate (ATP) through oxidative phosphorylation (OXPHOS). In mammals, the majority of OXPHOS complex subunits are encoded by nuclear deoxyribonucleic acid (DNA); however, 13 core subunits essential for the function of OXPHOS complexes I, III, IV, and V are encoded in the mitochondrial (mt) DNA (mtDNA) and are synthesized within the mitochondria by its own …

Mechanistic Study Of Diatrizoic Acid Induced Proximal Tubule Cytotoxicity, Dakota Blake Ward

Theses, Dissertations and Capstones

Radiocontrast media (RCM) are necessary for many diagnostic procedures such as arteriography, percutaneous coronary intervention (PCI), and computed tomography. Contrast-induced acute kidney injury (CI-AKI) is the third most common cause of hospital-associated kidney damage accounting for 10-25% of cases worldwide. The mechanisms of contrast-induced renal impairment are not entirely known, but diminished renal hemodynamics, inflammatory responses, and direct cytotoxicity have been hypothesized. The purpose of this study was to investigate the mechanisms of direct cytotoxicity observed in HK-2 cells following treatment with diatrizoic acid (DA) and to determine the source of this damage. Mitochondrial function, endoplasmic reticulum (ER) stress, oxidative …

Regulation Of Na-K-Atpase By Arachidonic Acid Metabolites In Intestinal Epithelial Cells, Niraj Nepa

Theses, Dissertations and Capstones

The integral membrane protein sodium potassium adenosine triphosphate (Na-K-ATPase), has been extensively studied in various animal cell models. Na-K-ATPase is a multifunctional enzyme which plays a significant role in cellular physiology by regulating electrochemical potential, cell volume, pH, cytosolic calcium, and many nutrient and electrolyte transport processes. As such, it has been implicated in the pathogenesis of inflammatory bowel diseases (IBD) and has been shown to play a vital role in the malabsorption of nutrients and electrolytes. In this context, a significant amount of research has been done over the last two decades to understand the mechanisms of alteration of …

Potential Applications Of Capsaicinoids In Small Cell Lung Cancer Therapy, Jamie Rae Friedman

Theses, Dissertations and Capstones

Lung cancer continues to be the leading cause of cancer related mortality worldwide. Lung cancer is not a single disease but an umbrella that encompasses two major classifications, nonsmall cell lung cancer (NSCLC) and small cell lung cancer (SCLC). SCLC represents about 15- 20% of all lung cancer cases and is almost exclusively diagnosed in smokers. Typically, patients will respond very well to first line treatment, but face inevitable relapse. The fact that SCLC still carries a grim 5-year survival rate of less than 5% highlights the lack of advancement in treatment options to effectively improve patient response and survival. …

Endogenous Antioxidant Overexpression As An Adjuvant To Diet Or Exercise Intervention As Therapy To Counteract Obesity And Beneficially Shift The Gut Microbiome, Deborah Lynn Amos

Theses, Dissertations and Capstones

Oxidative stress plays a key role in metabolic syndrome which includes obesity and cardiometabolic diseases. It is implicated that oxygen-derived free radicals generated during the mitochondrial electron transport chain alter the function of specific biological components, thus activating obesogenic pathways such as glucose and lipid signaling. Research on this topic is of vital importance as obesity is a high-risk factor in the development and progression of severe, debilitating, life-threatening maladies such as cardiometabolic diseases, chronic inflammatory pathologies, and cancer. Furthermore, there is no universal effective therapy to combat the rising rates of obesity with over 1.9 billion (39%) adults classified …

Naktide Targeted To Adipocytes Ameliorates Western Diet Induced Obesity, Rebecca D. Pratt

Theses, Dissertations and Capstones

Obesity has become a worldwide epidemic and is a major risk factor for metabolic syndrome. It is believed that cellular oxidant stress plays a key role in both the development and maintenance of obesity as well as its associated comorbidities such as diabetes, cardiovascular disease, and nonalcoholic steatohepatitis (NASH). We have previously reported that systemic administration of pNaKtide, which targets the Na/K-ATPase oxidant amplification loop was able to decrease oxidative stress and adiposity in mice fed a high fat and fructose supplemented western diet (WD). As adipocytes are believed to play an active role in the development of obesity and …

Understanding Pseudomonas Aeruginosa Alginate Regulation And Its Link To Chronic Lung Infections In Cystic Fibrosis Patients, Roy Al Ahmar

Theses, Dissertations and Capstones

Cystic Fibrosis (CF) is a genetic disorder caused by mutations in the gene encoding Cystic Fibrosis Transmembrane Conductance Regulator (CFTR). This disorder results in thick lung secretions which compromise the patient’s immune system. Chronic lung infections with Pseudomonas aeruginosa biofilms is a major factor that contributes to poor outcome for clinical treatment. The overall hypothesis of this dissertation is that small colony variant and pyrimidine biosynthesis are linked with biofilm formation, alginate production is dependent on MucA proteolysis, rifaximin can be repurposed to treat biofilm infection and multiplex PCR can be used to rapidly measure the bacterial cell density in …

Doxorubicin Cytotoxicity In A Human Proximal Tubular Epithelial Cell Line Was Attenuated By The Natural Product Resveratrol, Morghan Schuyler Getty

Theses, Dissertations and Capstones

The cancer chemotherapeutic agent doxorubicin (DOX), Adriamycin, is part of the treatment regimen for breast, ovarian, small cell lung cancer and acute/chronic lymphoid leukemia. Adverse effects associated with DOX are cardiotoxicity and nephrotoxicity. Interventions are needed to reduce DOX nephrotoxicity. Resveratrol (RES) is a phytochemical contained in grapes, berries and nuts, which possesses antioxidant and anticancer properties. This study tested the hypothesis that RES will attenuate DOX renal cytotoxicity in human noncancerous renal proximal tubular epithelial (HK-2) cells and that RES will reduce DOX mediated changes in mitochondrial function. HK-2 cells were plated and grown for 48 hours (h). Cells …

Investigation Of Ultrasound Targeted Microbubbles As A Therapeutic Gene Delivery System For Prostate Cancer, Rounak Paramjeet Nande

Theses, Dissertations and Capstones

A major challenge for effective gene therapy is systemic delivery of viruses carrying therapeutic genes into affected tissue. The immunogenic nature of human adenoviruses (Ads) limits their use for intratumoral (IT) injection in gene therapy. Ads transfection is further hampered by the fluctuating presence of Coxsackie and Adenovirus Receptor (CAR) and integrins on the cells’ surface. To circumvent these limitations we developed a novel approach wherein Ads are encapsulated inside the shell of lyophilized, lipid-encapsulated, perfluorocarbon microbubbles (MBs)/ultrasound (US) contrast agents, which act as delivery vehicles for a sitespecific gene transfer system.

We performed infection studies with Ad.GFP (Green Fluorescent …

Identification And Characterization Of Downstream Effector Protein(S) Regulated By P53 And Prb, Miranda B. Carper

Theses, Dissertations and Capstones

A commonality among cancer types is the high frequency of mutations that inhibit or alter signaling of the p53 and pRb (Retinoblastoma) tumor suppressors. These genes regulate processes vital for cancer suppression such as apoptosis, senescence, and cell cycle arrest among others. Loss of both p53 and pRb promotes processes that support cancer progression and is associated with decreased patient survival and increased rates of tumor reoccurrence. Although data points to the ability of p53 and pRb to collaborate and to inhibit tumorigenesis, it remains unclear how p53 and pRb cooperate toward this task. Using RNA expression profiling, 179 p53 …

Benzyl Isothiocyanate As An Adjuvant Chemotherapy Option For Head And Neck Squamous Cell Carcinoma, Mary Allison Wolf

Theses, Dissertations and Capstones

Isothiocyanates (ITCs) are natural phytochemicals produced by cruciferous vegetables. Recent evidence supports that, in addition to cancer prevention, ITCs can use various mechanisms to target malignant cells. Current therapies for cancer often provoke detrimental side effects, however clinical evidence supports that ITCs have little to no side effects in patients. Consequently, ITCs may be a promising treatment option for cancer patients, especially patients suffering from head and neck squamous cell carcinoma (HNSCC).

Despite recent improvements in cancer treatment, overall survival of advanced HNSCC has not improved in the past three decades. Metastasis and chemoresistance represent two detrimental events that greatly …

Role Of Iron In Ethanol Derived Hepatic Stress, Jesse A. Thornton

Theses, Dissertations and Capstones

Chronic alcohol abuse is the third leading cause of preventable death in the United States. Ethanol metabolism causes liver injury through alterations in hepatic metabolic state, redox status, and acetaldehyde adduct formations. Increased iron absorption is associated with chronic ethanol consumption and may play a role in ethanol induced oxidative stress. We tested the hypothesis that normal labile iron in the liver plays a role in ethanol related pathological stress, using C57/Bl6 mice pair-fed Lieber-DeCarli liquid ethanol diets for 11 and 22 weeks. Normal iron group mice received 55mg/kg iron as ferric citrate, whereas the low iron groups received 5mg/kg. …

The Role Of Ptip In Breast Cancer, Lina Niu

Theses, Dissertations and Capstones

In the U.S., breast cancer comprises about 30% of all cancer cases (excluding skin cancer) in women. Such a high incidence makes breast cancer a significant health concern, but our understanding of the molecular and cellular mechanisms of this disease is still limited. Growing evidence suggests that the development of human breast cancer may involve epigenetics, which attributes changes in phenotype to mechanisms other than changes in the DNA sequence itself. Histones as the chief proteins of chromatin work on gene expression, and methylation of histone 3 lysine 4 (H3K4) results in transcriptional activation. Lately, Paired box (Pax) trans-activation domain-interacting …

Redox Regulation Of Differentiation In Neuroblastoma, Anne Marie Silvis

Theses, Dissertations and Capstones

Neuroblastoma is the most common extracranial solid tumor in childhood, ranking third in prevalence among infant cancers. Despite intensive therapy with surgery, radiation and chemotherapy, there is a high chance of tumor recurrence. These children are therefore given retinoids in the maintenance phase to differentiate the tumor cells and to avoid/lessen this incidence. Although 13-cis retinoic acid (13-cis RA) is currently used to treat neuroblastoma, there is much evidence supporting the prevalence of its metabolite, all-trans retinoic acid (ATRA), to be the main signaling retinoid in vivo.

The SK-N-SH neuroblastoma cell line, which is composed of three sub-types: sympatheoadrenal neuroblasts …

Identification Of Genes Involved In Hematopoietic Stem Cell Differentiation And Leukemia Differentiation And Leukemia, Jasjeet Bhullar

Theses, Dissertations and Capstones

Hematopoiesis is maintained by a proper balance between self renewal and multipotent differentiation of the hematopoietic stem cells (HSC). Acute myelogenous leukemia (AML) is characterized by the blockage in the differentiation of HSC, while self renewal and proliferation is preserved. It is important to understand the mechanisms involved in the inhibition of hematopoietic differentiation and maintenance of the HSC state in order to develop better therapies for AML. In these studies I have explored the role of Hsp90, omega-3 fatty acids and YB-1 in hematopoietic differentiation. EML, a hematopoietic precursor cell line, was used as a model for the hematopoietic …

Treatment Strategies In Acute Myelogenous Leukemia : Investigating Hsp90 And P53 As Targets, Jennifer M. Napper

Theses, Dissertations and Capstones

Acute myelogenous leukemia (AML) is the deadliest of the lymphatic and bone marrow cancers. Patients diagnosed with AML have a five year survival rate of 23.4%. AML is characterized by an accumulation of undifferentiated and functionless myeloid precursors in the bone marrow and blood. Heat shock protein 90 (Hsp90) inhibitors, such as 17-AAG, an analog of geldanamycin (GM), are currently undergoing phase I, and II and III clinical trials for various cancers with mixed results. I found distinct responses to 17-AAG treatment among the AML cell lines tested. I also discovered two mutant TP53 alleles in Kasumi-3 cells, an AML …

The Expression And Function Of Hypoxia Inducible Factor-1Α In Human Melanoma, Sandeep S. Joshi

Theses, Dissertations and Capstones

Hypoxia inducible factor-1α (HIF-1α) protein, a key regulator of oxygen homeostasis, is stabilized under hypoxia and degraded under normal oxygen tension. Here, the human melanoma cells were found to express an elevated amount of HIF-1α mRNA and protein relative to normal human melanocytes under normoxic conditions. The amount of HIF-1α expressed is roughly correlated with the stage of melanoma from which the cell line was established. In addition, a splice variant mRNA of HIF-1α785 is expressed at higher levels than full-length HIF-1α mRNA in the more aggressive melanoma cells. This splice variant lacks part of the oxygen regulation domain. Ectopic …

Effects Of Microgravity On Cancer Stem Cells Cultured In A Nasa Developed Bioreactor: Chemotherapeutic Implications., Sarah Elizabeth Daron Kelly

Theses, Dissertations and Capstones

The purpose of this study was to investigate the effects of simulated microgravity on cancer cell growth. Simulated microgravity is a condition in which cells are in constant free-fall and in which they are able to grow suspended without the shear and stress. Microgravity allows for important insights into the cellular mechanism and may be key in understanding why some cells thrive in this condition and others go into apoptosis. Cancer stem cells (CSCs) are considered a subset of the bulk tumor responsible for initiating and maintaining cancer. SAOS-2 is a human bone cancer cell line which consists of a …

Deferasirox Decreases Age-Associated Iron Accumulation In The Aging F344bn Rat Heart, Ravi K. Arvapalli

Theses, Dissertations and Capstones

It is thought that aging in rats and humans is associated with increases in iron accumulation and these increases in iron may be associated with increased cellular apoptosis. Here we examine the relationship between cardiac iron levels and cardiomyocyte apoptosis in aged F344BN rats which were treated with an oral iron chelator (Deferasirox; 100mg/kg body. weight/day) for 6 months. Compared with 6- month controls, the levels of cardiac iron, cardiac apoptosis, FLC and DMT-1 were higher in 33-month hearts. Deferasirox treatment for six months decreased cardiac iron and this was associated with decreases in the number of apoptotic cardiac myocytes. …

Manganese Superoxide Dismutase Contributes To Cisplatin-Induced Cytotoxicity Rather Than All-Trans Retinoic Acid-Dependent Chemoresistance, Zina-Ann Cardozo

Theses, Dissertations and Capstones

Neuroblastoma is an extra-cranial solid tumor of the nervous system occurring predominantly in infants and children younger than five years of age. Neuroblastoma presents a challenge to therapy primarily due to a decreased responsiveness to anticancer agents like cisplatin (CDDP), leading to recurrence. Vitamin A and its derivatives, known as retinoids, are preventive against cancer and induce differentiation in some cell lines. Retinoids are now being tested clinically for the treatment of neuroblastoma. One major limitation to retinoid therapy is the development of chemoresistance. In the present study human SK-N-SH neuroblastoma cells pretreated with 10 μM all-trans retinoic acid (ATRA) …

Mlck/Actin Interaction In The Contracting A7r5 Cell And Vascular Smooth Muscle, Sean Eric Thatcher

Theses, Dissertations and Capstones

Myosin light chain kinase (MLCK) is an enzyme that phosphorylates the serine-19 residue on myosin regulatory light chains (MLCs) which serves to activate the Mg2+-ATPase of myosin. This catalytic activity is thought to be the primary role of MLCK; however, it has recently been suggested that MLCK’s actin binding and bundling properties may also be of importance in smooth muscle contraction. In the absence of calcium and calmodulin (CaM), MLCK will bundle actin filaments with its N-terminus. During calcium influx and subsequent CaM activation, MLCK binding to actin decreases resulting in unbundling of actin filaments and allows myosin and actin …

The Expression And Function Of Ppar And Hif-1 In Human Melanoma, Caroline Mills

Theses, Dissertations and Capstones

The first part of my dissertation focuses on the expression and function of PPARs in human melanoma. I found that the A375 cells were significantly growth inhibited in response to _PGJ2 and troglitazone treatment. HEMn-LP showed significant growth inhibition in response to troglitazone. I found that PPARγ and PPARδ mRNA is present in both the SK-Mel 28 and A375 cells. The relative level of PPARα mRNA expression is highest in SK-Mel 28 cells, ~3 fold higher relative to both the normal human melanocytes and A375 cells. PPARγ protein was ~50% higher in both SK-Mel 28 and A375 cells relative to …

Protein Kinase C Activity In Mouse Eggs Regulates Gamete Membrane Interaction, Hiroto Akabane

Theses, Dissertations and Capstones

Every mammalian life develops from one cell after fertilization of an egg by the sperm. The molecular pathways governing this event are still poorly understood. Numerous reports indicate that mammalian eggs highly express various protein kinase C (PKC) isoforms. Accordingly, we hypothesize that PKC activity in the egg plays an important role during egg-sperm membrane binding and fusion. In this study, we tested our hypothesis in mouse gametes using two types of PKC inhibitors (calphostin c and staurosporine) and the typical PKC activator, phorbol ester 12-tetradecanoylphorbol-13 acetate (PMA). After treatment with the individual drug, eggs were inseminated with sperm. The …