Medical Toxicology Commons^™

Expression Of Peroxiredoxin 1 And 4 Promotes Human Lung Cancer Malignancy, Hong Jiang, Lisha Wu, Murli Mishra, Hedy A. Chawsheen, Qiou Wei

Toxicology and Cancer Biology Faculty Publications

Members of the Peroxiredoxin (Prx) family are major cellular antioxidants that scavenge hydrogen peroxide and play essential roles in oxidative stress and cell signaling. 2-Cys Prxs, including Prx1, 2, 3 and 4, have been indicated in multiple oncogenic signaling pathways and thus may contribute to various processes of cancer development. The significance of 2-Cys Prxs in lung cancer development and their biological function in signal transduction have not been fully investigated. In this study we analyzed the expression of 2-Cys Prxs in lung cancer, and examined their levels of expression in a variety of cell lines established from human lung …

Responses Of Target And Non-Target Species To Algaecide Exposures, Alyssa Calomeni

All Theses

Laboratory experiments are often used to predict the responses of target and non-target species to chemical exposures in the field. In the first two experiments of this thesis, a rigorous evaluation of six algal viability measures was conducted. A definitive evaluation of the algal response measures was conducted using heat treatment to create known live: dead cell suspensions. Results from the response measures were compared to the known viability of the cell suspensions to determine their variance and accuracy. Copper-based algaecides were then used as a more realistic exposure to test the algal viability measures. When algal viability measures had …

Redox Proteomic Identification Of Hne-Bound Mitochondrial Proteins In Cardiac Tissues Reveals A Systemic Effect On Energy Metabolism After Doxorubicin Treatment, Y. Zhao, Sumitra Miriyala, L. Miao, Mihail I. Mitov, David M. Schnell, Sanjit Kumar Dhar, J. Cai, J. B. Klein, Rukhsana Sultana, D. Allan Butterfield, Mary Vore, I. Batinic-Haberle, Subbarao Bondada, Daret K. St. Clair

Toxicology and Cancer Biology Faculty Publications

Doxorubicin (DOX), one of the most effective anticancer drugs, is known to generate progressive cardiac damage, which is due, in part, to DOX-induced reactive oxygen species (ROS). The elevated ROS often induce oxidative protein modifications that result in alteration of protein functions. This study demonstrates that the level of proteins adducted by 4-hydroxy-2-nonenal (HNE), a lipid peroxidation product, is significantly increased in mouse heart mitochondria after DOX treatment. A redox proteomics method involving two-dimensional electrophoresis followed by mass spectrometry and investigation of protein databases identified several HNE-modified mitochondrial proteins, which were verified by HNE-specific immunoprecipitation in cardiac mitochondria from the …

Profiling Thiol Metabolites And Quantification Of Cellular Glutathione Using Ft-Icr-Ms Spectrometry, Sadakatali S. Gori, Pawel Lorkiewicz, Daniel S. Ehringer, Alex C. Belshoff, Richard M. Higashi, Teresa W-M Fan, Michael H. Nantz

Toxicology and Cancer Biology Faculty Publications

We describe preparation and use of the quaternary ammonium-based α-iodoacetamide QDE and its isotopologue *QDE as reagents for chemoselective derivatization of cellular thiols. Direct addition of the reagents to live cells followed by adduct extraction into n-butanol and analysis by FT-ICR-MS provided a registry of matched isotope peaks from which molecular formulae of thiol metabolites were derived. Acidification to pH 4 during cell lysis and adduct formation further improves the chemoselectivity for thiol derivatization. Examination of A549 human lung adenocarcinoma cells using this approach revealed cysteine, cysteinylglycine, glutathione, and homocysteine as principal thiol metabolites as well as the sulfinic acid …

Resveratrol And Cancer: Focus On In Vivo Evidence, Lindsay G. Carter, John A. D'Orazio, Kevin J. Pearson

Graduate Center for Nutritional Sciences Faculty Publications

Resveratrol is a naturally occurring polyphenol that provides a number of anti-aging health benefits including improved metabolism, cardioprotection, and cancer prevention. Much of the work on resveratrol and cancer comes from in vitro studies looking at resveratrol actions on cancer cells and pathways. There are, however, comparatively fewer studies that have investigated resveratrol treatment and cancer outcomes in vivo, perhaps limited by its poor bioavailability when taken orally. Although research in cell culture has shown promising and positive effects of resveratrol, evidence from rodents and humans is inconsistent. This review highlights the in vivo effects of resveratrol treatment on breast, …

Antagonistic Effects Of Myc And Hypoxia In Channeling Glucose And Glutamine Into De Novo Nucleotide Biosynthesis, Teresa W-M Fan, Anne Le, Zachary Stine, Ye Yang, Karen Zeller, Weiqiang Zhou, Hongkai Ji, Richard M. Higashi, Chi Dang, Andrew N. Lane

Toxicology and Cancer Biology Presentations

No abstract provided.

Targeting Lactate Dehydrogenase-A Inhibits Tumorigenesis And Tumor Progression In Mouse Models Of Lung Cancer And Impacts Tumor-Initiating Cells, Han Xie, Jun-Ichi Hanai, Jian-Guo Ren, Lev Kats, Kerri Burgess, Parul Bhargava, Sabina Signoretti, Julia Billiard, Kevin J. Duffy, Aaron Grant, Xiaoen Wang, Pawel Lorkiewicz, Sabrina Schatzman, Michael Bousamra, Andrew N. Lane, Richard M. Higashi, Teresa W-M Fan, Pier Paolo Pandolfi, Vikas P. Sukhatme, Pankaj Seth

Toxicology and Cancer Biology Faculty Publications

The lactate dehydrogenase-A (LDH-A) enzyme catalyzes the interconversion of pyruvate and lactate, is upregulated in human cancers, and is associated with aggressive tumor outcomes. Here we use an inducible murine model and demonstrate that inactivation of LDH-A in mouse models of NSCLC driven by oncogenic K-RAS or EGFR leads to decreased tumorigenesis and disease regression in established tumors. We also show that abrogation of LDH-A results in reprogramming of pyruvate metabolism, with decreased lactic fermentation in vitro, in vivo, and ex vivo. This was accompanied by reactivation of mitochondrial function in vitro, but not in vivo …

Sirt1 Deletion Leads To Enhanced Inflammation And Aggravates Endotoxin-Induced Acute Kidney Injury, Rong Gao, Jiao Chen, Yuxin Hu, Zhenyu Li, Shuxia Wang, Sreerama Shetty, Jian Fu

Toxicology and Cancer Biology Faculty Publications

Bacterial endotoxin has been known to induce excessive inflammatory responses and acute kidney injury. In the present study, we used a mouse model of endotoxemia to investigate the role of Sirt1 in inflammatory kidney injury. We examined molecular and cellular responses in inducible Sirt1 knockout (Sirt1-/-) mice and wild type littermates (Sirt1+/+) in lipopolysaccharide (LPS)-induced kidney injury. Our studies demonstrated that Sirt1 deletion caused aggravated kidney injury, which was associated with increased inflammatory responses including elevated pro-inflammatory cytokine production, and increased ICAM-1 and VCAM-1 expression. Inflammatory signaling such as STAT3/ERK phosphorylation and NF-κB activation was markedly elevated in kidney tissues …

Characterizing The Chronic Toxicity Of Ion Mixtures To Ceriodaphnia Dubia Using Two Experimental Designs, Katherine Johnson

All Theses

Total Dissolved Solids, commonly referred to as TDS, is a measure of all organic and inorganic substances that pass through a 2-um filter and are naturally found in aquatic environments. Anthropogenic activities such as agricultural irrigation, road salt runoff, hydraulic fracturing, and coal-fired power plant effluents can increase TDS concentrations of freshwater ecosystems ultimately increasing salinity. Aquatic organisms actively manage the ion balance between their external and internal environments. Freshwater organisms use energy to pump sodium in from the environment, while losing it through passive diffusion. If the external ion concentration changes significantly, these organisms must allocate more energy towards …

Assessing The Relationship Between The Blood-Air Partition Coefficient And Fractional Uptake Of Inspired Halothane, Acetone, And Ethanol Vapors In The Airways Of The C57bl/6j Mouse, Joshua Baruch Baldino

Honors Scholar Theses

The following series of studies investigates the elimination and uptake trends of halothane, acetone, and ethanol vapors in the airways of C57BL/6J mice. These vapors were chosen because they span a wide range of solubilities, as indicated by their blood-air partition coefficients, and are not associated with any significant airway metabolism or reactivity with tissue substrates in vivo. Mice were exposed to a homogeneous vapor mixture containing a 1:1:1 ratio of halothane, acetone, and ethanol at relative concentrations of approximately 10 ppm. Exposure studies were performed with mice in two states, conscious and deceased, in order to provide control …

Effects Of Creosote-Contaminated Sediment Extracts On Mouse Macrophage Physiology And Function, Rayna Silva

All Theses

The southern branch of the Elizabeth River, at Portsmouth Virginia is one of the most polluted systems in North America. This harbor estuary system is also home to the Atlantic Wood Superfund site, which is heavily contaminated with creosote from the Atlantic Wood (AW) preservative company that ceased production in the later 1990s. Creosote is a mixture of polyaromatic hydrocarbons (PAHs), metals, and numerous aliphatic hydrocarbons, and well known to be carcinogenic. The toxicity of sediments and pore waters from the AW site has been studied extensively using Fundulus heteroclitus, also known as the mummichog, or Atlantic killifish. Most adult …

Redox-Mediated And Ionizing-Radiation-Induced Inflammatory Mediators In Prostate Cancer Development And Treatment, Lu Miao, Aaron K. Holley, Yanming Zhao, William H. St. Clair, Daret K. St. Clair

Toxicology and Cancer Biology Faculty Publications

SIGNIFICANCE: Radiation therapy is widely used for treatment of prostate cancer. Radiation can directly damage biologically important molecules; however, most effects of radiation-mediated cell killing are derived from the generated free radicals that alter cellular redox status. Multiple proinflammatory mediators can also influence redox status in irradiated cells and the surrounding microenvironment, thereby affecting prostate cancer progression and radiotherapy efficiency.

RECENT ADVANCES: Ionizing radiation (IR)-generated oxidative stress can regulate and be regulated by the production of proinflammatory mediators. Depending on the type and stage of the prostate cancer cells, these proinflammatory mediators may lead to different biological consequences ranging from …

Fused In Sarcoma Is A Novel Regulator Of Manganese Superoxide Dismutase Gene Transcription, Sanjit Kumar Dhar, Jiayu Zhang, Jozsef Gal, Yong Xu, Lu Miao, Bert C. Lynn, Haining Zhu, Edward J. Kasarskis, Daret K. St. Clair

Toxicology and Cancer Biology Faculty Publications

AIMS: FUsed in sarcoma (FUS) is a multifunctional DNA/RNA-binding protein that possesses diverse roles, such as RNA splicing, RNA transport, DNA repair, translation, and transcription. The network of enzymes and processes regulated by FUS is far from being fully described. In this study, we have focused on the mechanisms of FUS-regulated manganese superoxide dismutase (MnSOD) gene transcription.

RESULTS: Here we demonstrate that FUS is a component of the transcription complex that regulates the expression of MnSOD. Overexpression of FUS increased MnSOD expression in a dose-dependent manner and knockdown of FUS by siRNA led to the inhibition of MnSOD gene transcription. …

Redox-Modulated Phenomena And Radiation Therapy: The Central Role Of Superoxide Dismutases, Aaron K. Holley, Lu Miao, Yanming Zhao, Daret K. St. Clair, William H. St. Clair

Toxicology and Cancer Biology Faculty Publications

SIGNIFICANCE: Ionizing radiation is a vital component in the oncologist's arsenal for the treatment of cancer. Approximately 50% of all cancer patients will receive some form of radiation therapy as part of their treatment regimen. DNA is considered the major cellular target of ionizing radiation and can be damaged directly by radiation or indirectly through reactive oxygen species (ROS) formed from the radiolysis of water, enzyme-mediated ROS production, and ROS resulting from altered aerobic metabolism.

RECENT ADVANCES: ROS are produced as a byproduct of oxygen metabolism, and superoxide dismutases (SODs) are the chief scavengers. ROS contribute to the radioresponsiveness of …

Nuclear Interaction Between Adr-Induced P65 And P53 Mediates Cardiac Injury In Inos (−/−) Mice, Marsha P. Cole, Jitbanjong Tangpong, Terry D. Oberley, Luksana Chaiswing, Kinsley K. Kiningham, Daret K. St. Clair

Toxicology and Cancer Biology Faculty Publications

Adriamycin (ADR) treatment causes an imbalance in the levels of nitric oxide (^•NO) and superoxide (O₂^•−) production leading to cardiac injury. Previously we demonstrated that mice lacking inducible nitric oxide synthase (iNOS) have increased oxidative stress and mitochondrial injury. The molecular events leading to increased mitochondrial injury in iNOS deficient mice is unknown. ADR in the absence of iNOS preferentially activates a proapoptotic pathway without a concurrent increase in prosurvival pathways. Treatment with ADR leads to an increase in DNA binding activity of nuclear factor kappa B (NFκB) and p53 in wildtype mice. Following ADR …

Repair Of Oxidative Dna Damage And Cancer: Recent Progress In Dna Base Excision Repair, Timothy L. Scott, Suganya Rangaswamy, Christina A. Wicker, Tadahide Izumi

Toxicology and Cancer Biology Faculty Publications

SIGNIFICANCE: Reactive oxygen species (ROS) are generated by exogenous and environmental genotoxins, but also arise from mitochondria as byproducts of respiration in the body. ROS generate DNA damage of which pathological consequence, including cancer is well established. Research efforts are intense to understand the mechanism of DNA base excision repair, the primary mechanism to protect cells from genotoxicity caused by ROS.

RECENT ADVANCES: In addition to the notion that oxidative DNA damage causes transformation of cells, recent studies have revealed how the mitochondrial deficiencies and ROS generation alter cell growth during the cancer transformation.

CRITICAL ISSUES: The emphasis of this …

Ether Bridge Formation In Loline Alkaloid Biosynthesis, Juan Pan, Minakshi Bhardwaj, Jerome Ralph Faulkner, Padmaja Nagabhyru, Nikki D. Charlton, Richard M. Higashi, Anne-Frances Miller, Carolyn A Young, Robert B. Grossman, Christopher L. Schardl

Toxicology and Cancer Biology Faculty Publications

Lolines are potent insecticidal agents produced by endophytic fungi of cool-season grasses. These alkaloids are composed of a pyrrolizidine ring system and an uncommon ether bridge linking carbons 2 and 7. Previous results indicated that 1-aminopyrrolizidine was a pathway intermediate. We used RNA interference to knock down expression of lolO, resulting in the accumulation of an alkaloid identified as exo-1-acetamidopyrrolizidine based on high-resolution MS and NMR. Genomes of endophytes differing in alkaloid profiles were sequenced, revealing that those with mutated lolO accumulated exo-1-acetamidopyrrolizidine but no lolines. Heterologous expression of wild-type lolO complemented a lolO mutant, resulting in …

Intramolecular Telomeric G-Quadruplexes Dramatically Inhibit Dna Synthesis By Replicative And Translesion Polymerases, Revealing Their Potential To Lead To Genetic Change, Deanna N. Edwards, Amrita Machwe, Zhigang Wang, David K. Orren

Toxicology and Cancer Biology Faculty Publications

Recent research indicates that hundreds of thousands of G-rich sequences within the human genome have the potential to form secondary structures known as G-quadruplexes. Telomeric regions, consisting of long arrays of TTAGGG/AATCCC repeats, are among the most likely areas in which these structures might form. Since G-quadruplexes assemble from certain G-rich single-stranded sequences, they might arise when duplex DNA is unwound such as during replication. Coincidentally, these bulky structures when present in the DNA template might also hinder the action of DNA polymerases. In this study, single-stranded telomeric templates with the potential to form G-quadruplexes were examined for their effects …

Paracrine Apoptotic Effect Of P53 Mediated By Tumor Suppressor Par-4, Ravshan Burikhanov, Tripti Shrestha-Bhattarai, Nikhil Hebbar, Shirley Qiu, Yanming Zhao, Gerard P. Zambetti, Vivek M. Rangnekar

Radiation Medicine Faculty Publications

The guardian of the genome, p53, is often mutated in cancer and may contribute to therapeutic resistance. Given that p53 is intact and functional in normal tissues, we harnessed its potential to inhibit the growth of p53-deficient cancer cells. Specific activation of p53 in normal fibroblasts selectively induced apoptosis in p53-deficient cancer cells. This paracrine effect was mediated by p53-dependent secretion of the tumor suppressor Par-4. Accordingly, the activation of p53 in normal mice, but not p53⁻/⁻ or Par-4⁻/⁻ mice, caused systemic elevation of Par-4, which induced apoptosis of p53-deficient tumor cells. Mechanistically, p53 …

Therapeutic Efficacy Of Cerium Oxide Nanoparticles Against Sepsis Induced Multi-Organ Dysfunction Syndrome In Sprague Dawley Rats, Nandini Durga Prasanna Kumar Manne

Theses, Dissertations and Capstones

Sepsis is a generalized term that signifies the presence of a pathogen in the blood stream to which the body responds by eliciting a systemic inflammatory response. Although sepsis is the leading cause of death in non-coronary intensive care units in United States, there are currently no FDA approved therapeutic drugs to treat this disorder. Cerium oxide nanoparticles (CeO₂) have been shown to exhibit anti-oxidant, anti-inflammatory, and anti-bacterial properties both in vitro and in vivo. Whether CeO₂ nanoparticles can be used for the treatment of sepsis is currently unclear.

To investigate whether CeO₂ nanoparticles can …