Medicine and Health Sciences Commons^™

Tumor Suppressor Pdcd4 Attenuates Sin1 Translation To Inhibit Invasion In Colon Carcinoma, Qing Wang, Jiang Zhu, Ya-Wen Wang, Yong Dai, Yanlei Wang, Chi Wang, Jinpeng Liu, Alyson Baker, Nancy H. Colburn, Hsin-Sheng Yang

Toxicology and Cancer Biology Faculty Publications

Programmed cell death 4 (Pdcd4), a tumor invasion suppressor, is frequently downregulated in colorectal cancer and other cancers. In this study, we find that loss of Pdcd4 increases the activity of mammalian target of rapamycin complex 2 (mTORC2) and thereby upregulates Snail expression. Examining the components of mTORC2 showed that Pdcd4 knockdown increased the protein but not mRNA level of stress-activated-protein kinase interacting protein 1 (Sin1), which resulted from enhanced Sin1 translation. To understand how Pdcd4 regulates Sin1 translation, the SIN1 5′ untranslated region (5′UTR) was fused with luciferase reporter and named as 5′Sin1-Luc. Pdcd4 knockdown/knockout significantly increased the translation …

Corticosterone Administration Up-Regulated Expression Of Norepinephrine Transporter And Dopamine Β-Hydroxylase In Rat Locus Coeruleus And Its Terminal Regions, Yan Fan, Ping Ping Chen, Ying Li, Kui Cui, Daniel M. Noel, Elizabeth D. Cummins, Daniel J. Peterson, Russell W. Brown, Meng-Yang Zhu

Russell W. Brown

Stress has been reported to activate the locus coeruleus (LC)-noradrenergic system. In this study, corticosterone (CORT) was orally administrated to rats for 21 days to mimic stress status. In situ hybridization measurements showed that CORT ingestion significantly increased mRNA levels of norepinephrine transporter (NET) and dopamine β-hydroxylase (DBH) in the LC region. Immunofluorescence staining and western blotting revealed that CORT treatment also increased protein levels of NET and DBH in the LC, as well as NET protein levels in the hippocampus, the frontal cortex and the amygdala. However, CORT-induced increase in DBH protein levels only appeared in the hippocampus and …

Disruption Of Hippocampal Multisynaptic Networks By General Anesthetics., Min-Ching Kuo, L Stan Leung

Physiology and Pharmacology Publications

BACKGROUND: Previous studies showed that synaptic transmission is affected by general anesthetics, but an anesthetic dose response in freely moving animals has not been done. The hippocampus provides a neural network for the evaluation of isoflurane and pentobarbital on multisynaptic transmission that is relevant to memory function.

METHODS: Male Long-Evans rats were implanted with multichannel and single electrodes in the hippocampus. Spontaneous local field potentials and evoked field potentials were recorded in freely behaving rats before (baseline) and after various doses of isoflurane (0.25 to 1.5%) and sodium pentobarbital (10 mg/kg intraperitoneal).

RESULTS: Monosynaptic population excitatory postsynaptic potentials at the …

Epigenetic Suppression Of Hippocampal Calbindin-D28k By Δfosb Drives Seizure-Related Cognitive Deficits., Jason C. You, Kavitha Muralidharan, Jin W. Park, Iraklis Petrof, Mark S. Pyfer, Brian F. Corbett, John J. Lafrancois, Yi Zheng, Xiaohong Zhang, Carrie A. Mohila, Daniel Yoshor, Robert A. Rissman, Eric J. Nestler, Helen E. Scharfman, Jeannie Chin

Department of Neuroscience Faculty Papers

The calcium-binding protein calbindin-D28k is critical for hippocampal function and cognition, but its expression is markedly decreased in various neurological disorders associated with epileptiform activity and seizures. In Alzheimer's disease (AD) and epilepsy, both of which are accompanied by recurrent seizures, the severity of cognitive deficits reflects the degree of calbindin reduction in the hippocampal dentate gyrus (DG). However, despite the importance of calbindin in both neuronal physiology and pathology, the regulatory mechanisms that control its expression in the hippocampus are poorly understood. Here we report an epigenetic mechanism through which seizures chronically suppress hippocampal calbindin expression and impair cognition. …

Differentiation And Protective Capacity Of Virus-Specific Cd8, Vesselin T. Tomov, Olesya Palko, Chi Wai Lau, Ajinkya Pattekar, Yuhang Sun, Ralitza Tacheva, Bertram Bengsch, Sasikanth Manne, Gabriela L. Cosma, Laurence C. Eisenlohr, Timothy J. Nice, Herbert W. Virgin, E. John Wherry

Department of Microbiology and Immunology Faculty Papers

Noroviruses can establish chronic infections with active viral shedding in healthy humans but whether persistence is associated with adaptive immune dysfunction is unknown. We used genetically engineered strains of mouse norovirus (MNV) to investigate CD8⁺ T cell differentiation during chronic infection. We found that chronic infection drove MNV-specific tissue-resident memory (Trm) CD8⁺ T cells to a differentiation state resembling inflationary effector responses against latent cytomegalovirus with only limited evidence of exhaustion. These MNV-specific Trm cells remained highly functional yet appeared ignorant of ongoing viral replication. Pre-existing MNV-specific Trm cells provided partial protection against chronic infection but largely ceased …

The Dual Role Of Group V Secretory Phospholipase A2 In Pancreatic Β-Cells, Preetha Shridas, Victoria P. Noffsinger, Andrea C. Trumbauer, Nancy R. Webb

Saha Cardiovascular Research Center Faculty Publications

Purpose

Group X (GX) and group V (GV) secretory phospholipase A₂ (sPLA₂) potently release arachidonic acid (AA) from the plasma membrane of intact cells. We previously demonstrated that GX sPLA₂ negatively regulates glucose-stimulated insulin secretion (GSIS) by a prostaglandin E2 (PGE2)-dependent mechanism. In this study we investigated whether GV sPLA₂ similarly regulates GSIS.

Methods

GSIS and pancreatic islet-size were assessed in wild-type (WT) and GV sPLA₂-knock out (GV KO) mice. GSIS was also assessed ex vivo in isolated islets and in vitro using MIN6 pancreatic beta cell lines with or without GV sPLA …

The Trophic Life Cycle Stage Of The Opportunistic Fungal Pathogen Pneumocystis Murina Hinders The Ability Of Dendritic Cells To Stimulate Cd4+ T Cell Responses, Heather M. Evans, Andrew Simpson, Shu Shen, Arnold J. Stromberg, Carol L. Pickett, Beth A. Garvy

Microbiology, Immunology, and Molecular Genetics Faculty Publications

The life cycle of the opportunistic fungal pathogen Pneumocystis murina consists of a trophic stage and an ascus-like cystic stage. Infection with the cyst stage induces proinflammatory immune responses, while trophic forms suppress the cytokine response to multiple pathogen-associated molecular patterns (PAMPs), including β-glucan. A targeted gene expression assay was used to evaluate the dendritic cell response following stimulation with trophic forms alone, with a normal mixture of trophic forms and cysts, or with β-glucan. We demonstrate that stimulation with trophic forms downregulated the expression of multiple genes normally associated with the response to infection, including genes encoding …

Decorin-Evoked Paternally Expressed Gene 3 (Peg3) Is An Upstream Regulator Of The Transcription Factor Eb (Tfeb) In Endothelial Cell Autophagy., Thomas Neill, Catherine Sharpe, Rick T. Owens, Renato V. Iozzo

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Macroautophagy is a fundamental and evolutionarily conserved catabolic process that eradicates damaged and aging macromolecules and organelles in eukaryotic cells. Decorin, an archetypical small leucine-rich proteoglycan, initiates a protracted autophagic program downstream of VEGF receptor 2 (VEGFR2) signaling that requires paternally expressed gene 3 (PEG3). We have discovered that PEG3 is an upstream transcriptional regulator of transcription factor EB (TFEB), a master transcription factor of lysosomal biogenesis, for decorin-evoked endothelial cell autophagy. We found a functional requirement of PEG3 for TFEB transcriptional induction and nuclear translocation in human umbilical vein endothelial and PAER2 cells. Mechanistically, inhibiting VEGFR2 or AMP-activated protein …

Rabies Screen Reveals Gpe Control Of Cocaine-Triggered Plasticity., Kevin T. Beier, Christina K. Kim, Paul Hoerbelt, Lin Wai Hung, Boris D. Heifets, Katherine E. Deloach, Timothy J. Mosca, Sophie Neuner, Karl Deisseroth, Liqun Luo, Robert C. Malenka

Department of Neuroscience Faculty Papers

Identification of neural circuit changes that contribute to behavioural plasticity has routinely been conducted on candidate circuits that were preselected on the basis of previous results. Here we present an unbiased method for identifying experience-triggered circuit-level changes in neuronal ensembles in mice. Using rabies virus monosynaptic tracing, we mapped cocaine-induced global changes in inputs onto neurons in the ventral tegmental area. Cocaine increased rabies-labelled inputs from the globus pallidus externus (GPe), a basal ganglia nucleus not previously known to participate in behavioural plasticity triggered by drugs of abuse. We demonstrated that cocaine increased GPe neuron activity, which accounted for the …

Loss Of Fructose-1,6-Bisphosphatase Induces Glycolysis And Promotes Apoptosis Resistance Of Cancer Stem-Like Cells: An Important Role In Hexavalent Chromium-Induced Carcinogenesis, Jin Dai, Yanli Ji, Wei Wang, Donghern Kim, Leonard Yenwong Fai, Lei Wang, Jia Luo, Zhuo Zhang

Toxicology and Cancer Biology Faculty Publications

Hexavalent chromium (Cr(VI)) compounds are confirmed human carcinogens for lung cancer. Our previous studies has demonstrated that chronic exposure of human bronchial epithelial BEAS-2B cells to low dose of Cr(VI) causes malignant cell transformation. The acquisition of cancer stem cell-like properties is involved in the initiation of cancers. The present study has observed that a small population of cancer stem-like cells (BEAS-2B-Cr-CSC) exists in the Cr(VI)-transformed cells (BEAS-2B-Cr). Those BEAS-2B-Cr-CSC exhibit extremely reduced capability of generating reactive oxygen species (ROS) and apoptosis resistance. BEAS-2B-Cr-CSC are metabolic inactive as evidenced by reductions in oxygen consumption, glucose uptake, ATP production, and lactate …

Gucy2c Signaling Opposes The Acute Radiation-Induced Gi Syndrome., Peng Li, Evan Wuthrick, Jeff A. Rappaport, Crystal Kraft, Jieru E. Lin, Glen Marszalowicz, Adam E. Snook, Tingting Zhan, Terry M. Hyslop, Scott A. Waldman

Department of Pharmacology and Experimental Therapeutics Faculty Papers

High doses of ionizing radiation induce acute damage to epithelial cells of the gastrointestinal (GI) tract, mediating toxicities restricting the therapeutic efficacy of radiation in cancer and morbidity and mortality in nuclear disasters. No approved prophylaxis or therapy exists for these toxicities, in part reflecting an incomplete understanding of mechanisms contributing to the acute radiation-induced GI syndrome (RIGS). Guanylate cyclase C (GUCY2C) and its hormones guanylin and uroguanylin have recently emerged as one paracrine axis defending intestinal mucosal integrity against mutational, chemical, and inflammatory injury. Here, we reveal a role for the GUCY2C paracrine axis in compensatory mechanisms opposing RIGS. …

Silver Oxide Coatings With High Silver-Ion Elution Rates And Characterization Of Bactericidal Activity., Sarah S Goderecci, Eric Kaiser, Michael Yanakas, Zachary Norris, Jeffrey Scaturro, Robert Oszust, Clarence D Medina, Fallon Waechter, Min Heon, Robert R Krchnavek, Lei Yu, Samuel E Lofland, Renee M Demarest, Gregory A Caputo, Jeffrey D Hettinger

Rowan-Virtua School of Osteopathic Medicine Faculty Scholarship

This paper reports the synthesis and characterization of silver oxide films for use as bactericidal coatings. Synthesis parameters, dissolution/elution rate, and bactericidal efficacy are reported. Synthesis conditions were developed to create AgO, Ag₂O, or mixtures of AgO and Ag₂O on surfaces by reactive magnetron sputtering. The coatings demonstrate strong adhesion to many substrate materials and impede the growth of all bacterial strains tested. The coatings are effective in killing Escherichia coli and Staphylococcus aureus, demonstrating a clear zone-of-inhibition against bacteria growing on solid media and the ability to rapidly inhibit bacterial growth in planktonic culture. Additionally, the coatings exhibit very …

Probing The Metabolic Phenotype Of Breast Cancer Cells By Multiple Tracer Stable Isotope Resolved Metabolomics, Andrew N. Lane, Julie Tan, Yali Wang, Jun Yan, Richard M. Higashi, Teresa W. -M. Fan

Center for Environmental and Systems Biochemistry Faculty Publications

Breast cancers vary by their origin and specific set of genetic lesions, which gives rise to distinct phenotypes and differential response to targeted and untargeted chemotherapies. To explore the functional differences of different breast cell types, we performed Stable Isotope Resolved Metabolomics (SIRM) studies of one primary breast (HMEC) and three breast cancer cells (MCF-7, MDAMB-231, and ZR75-1) having distinct genotypes and growth characteristics, using ¹³C₆-glucose, ¹³C-1+2-glucose, ¹³C₅,¹⁵N₂-Gln, ¹³C₃-glycerol, and ¹³C₈-octanoate as tracers. These tracers were designed to probe the central energy producing …

Hyperfiltration-Associated Biomechanical Forces In Glomerular Injury And Response: Potential Role For Eicosanoids., Mukut Sharma, Ram Sharma, Ellen T. Mccarthy, Virginia J. Savin, Tarak Srivastava

Manuscripts, Articles, Book Chapters and Other Papers

Hyperfiltration is a well-known risk factor in progressive loss of renal function in chronic kidney disease (CKD) secondary to various diseases. A reduced number of functional nephrons due to congenital or acquired cause(s) results in hyperfiltration in the remnant kidney. Hyperfiltration-associated increase in biomechanical forces, namely pressure-induced tensile stress and fluid flow-induced shear stress (FFSS) determine cellular injury and response. We believe the current treatment of CKD yields limited success because it largely attenuates pressure-induced tensile stress changes but not the effect of FFSS on podocytes. Studies on glomerular podocytes, tubular epithelial cells and bone osteocytes provide evidence for a …

Thiamine Deficiency And Neurodegeneration: The Interplay Among Oxidative Stress, Endoplasmic Reticulum Stress, And Autophagy, Dexiang Liu, Zunji Ke, Jia Luo

Pharmacology and Nutritional Sciences Faculty Publications

Thiamine (vitamin B1) is an essential nutrient and indispensable for normal growth and development of the organism due to its multilateral participation in key biochemical and physiological processes. Humans must obtain thiamine from their diet since it is synthesized only in bacteria, fungi, and plants. Thiamine deficiency (TD) can result from inadequate intake, increased requirement, excessive deletion, and chronic alcohol consumption. TD affects multiple organ systems, including the cardiovascular, muscular, gastrointestinal, and central and peripheral nervous systems. In the brain, TD causes a cascade of events including mild impairment of oxidative metabolism, neuroinflammation, and neurodegeneration, which are commonly observed in …

Calcineurin Dysregulation Underlies Spinal Cord Injury-Induced K(+) Channel Dysfunction In Drg Neurons., Benjamin M. Zemel, Tanziyah Muqeem, Eric V. Brown, Miguel Goulão, Mark W Urban, Stephen R. Tymanskyj, Angelo C. Lepore, Manuel Covarrubias

Department of Neuroscience Faculty Papers

Dysfunction of the fast-inactivating Kv3.4 potassium current in dorsal root ganglion (DRG) neurons contributes to the hyperexcitability associated with persistent pain induced by spinal cord injury (SCI). However, the underlying mechanism is not known. In light of our previous work demonstrating modulation of the Kv3.4 channel by phosphorylation, we investigated the role of the phosphatase calcineurin (CaN) using electrophysiological, molecular, and imaging approaches in adult female Sprague Dawley rats. Pharmacological inhibition of CaN in small-diameter DRG neurons slowed repolarization of the somatic action potential (AP) and attenuated the Kv3.4 current. Attenuated Kv3.4 currents also exhibited slowed inactivation. We observed similar …

Inhibition Of Post-Transcriptional Steps In Ribosome Biogenesis Confers Cytoprotection Against Chemotherapeutic Agents In A P53-Dependent Manner, Russell T Sapio, Anastasiya N Nezdyur, Matthew Krevetski, Leonid Anikin, Vincent J Manna, Natalie Minkovsky, Dimitri G Pestov

Rowan-Virtua School of Osteopathic Medicine Faculty Scholarship

The p53-mediated nucleolar stress response associated with inhibition of ribosomal RNA transcription was previously shown to potentiate killing of tumor cells. Here, we asked whether targeting of ribosome biogenesis can be used as the basis for selective p53-dependent cytoprotection of nonmalignant cells. Temporary functional inactivation of the 60S ribosome assembly factor Bop1 in a 3T3 cell model markedly increased cell recovery after exposure to camptothecin or methotrexate. This was due, at least in part, to reversible pausing of the cell cycle preventing S phase associated DNA damage. Similar cytoprotective effects were observed after transient shRNA-mediated silencing of Rps19, but not …

Characterization Of A Far-Red Analog Of Ghrelin For Imaging Ghs-R In P19-Derived Cardiomyocytes., Gregory A F Douglas, Rebecca Mcgirr, Carlie L Charlton, Dov B Kagan, Lisa M Hoffman, Leonard G Luyt, Savita Dhanvantari

Lisa Hoffman

Ghrelin and its receptor, the growth hormone secretagogue receptor (GHS-R), are expressed in the heart, and may function to promote cardiomyocyte survival, differentiation and contractility. Previously, we had generated a truncated analog of ghrelin conjugated to fluorescein isothiocyanate for the purposes of determining GHS-R expression in situ. We now report the generation and characterization of a far-red ghrelin analog, [Dpr(3)(octanoyl), Lys(19)(Cy5)]ghrelin (1-19), and show that it can be used to image changes in GHS-R in developing cardiomyocytes. We also generated the des-acyl analog, des-acyl [Lys(19)(Cy5)]ghrelin (1-19) and characterized its binding to mouse heart sections. Receptor binding affinity of Cy5-ghrelin as …

Abl Kinase Regulation By Braf/Erk And Cooperation With Akt In Melanoma, Aditi Jain, Rakshamani Tripathi, Courtney P. Turpin, Chi Wang, Rina Plattner

Pharmacology and Nutritional Sciences Faculty Publications

The melanoma incidence continues to increase, and the disease remains incurable for many due to its metastatic nature and high rate of therapeutic resistance. In particular, melanomas harboring BRAF^V600E and PTEN mutations often are resistant to current therapies, including BRAF inhibitors (BRAFi) and immune checkpoint inhibitors. Abl kinases (Abl/Arg) are activated in melanomas and drive progression; however, their mechanism of activation has not been established. Here we elucidate a novel link between BRAF^V600E/ERK signaling and Abl kinases. We demonstrate that BRAF^V600E/ERK play a critical role in binding, phosphorylating and regulating Abl localization and Abl/Arg activation …

Targeting Hepatic Heparin-Binding Egf-Like Growth Factor (Hb-Egf) Induces Anti-Hyperlipidemia Leading To Reduction Of Angiotensin Ii-Induced Aneurysm Development, Seonwook Kim, Lihua Yang, Seongu Kim, Richard G. Lee, Mark J. Graham, Judith A. Berliner, Aldons J. Lusis, Lei Cai, Ryan E. Temel, Debra L. Rateri, Sangderk Lee

Saha Cardiovascular Research Center Faculty Publications

Objective

The upregulated expression of heparin binding EGF-like growth factor (HB-EGF) in the vessel and circulation is associated with risk of cardiovascular disease. In this study, we tested the effects of HB-EGF targeting using HB-EGF-specific antisense oligonucleotide (ASO) on the development of aortic aneurysm in a mouse aneurysm model.

Approach and results

Low-density lipoprotein receptor (LDLR) deficient mice (male, 16 weeks of age) were injected with control and HB-EGF ASOs for 10 weeks. To induce aneurysm, the mice were fed a high fat diet (22% fat, 0.2% cholesterol; w/w) at 5 week point of ASO administration and infused with angiotensin …

April:Taci Axis Is Dispensable For The Immune Response To Rabies Vaccination., Shannon L. Haley, Evgeni P. Tzvetkov, Andrew G. Lytle, Kishore R. Alugupalli, Joseph R. Plummer, James P. Mcgettigan

Department of Microbiology and Immunology Faculty Papers

There is significant need to develop a single-dose rabies vaccine to replace the current multi-dose rabies vaccine regimen and eliminate the requirement for rabies immune globulin in post-exposure settings. To accomplish this goal, rabies virus (RABV)-based vaccines must rapidly activate B cells to secrete antibodies which neutralize pathogenic RABV before it enters the CNS. Increased understanding of how B cells effectively respond to RABV-based vaccines may improve efforts to simplify post-exposure prophylaxis (PEP) regimens. Several studies have successfully employed the TNF family cytokine a proliferation-inducing ligand (APRIL) as a vaccine adjuvant. APRIL binds to the receptors TACI and B cell …

Brain Microvascular Injury And White Matter Disease Provoked By Diabetes-Associated Hyperamylinemia, Han Ly, Nirmal Verma, Fengen Wu, Miao Liu, Kathryn E. Saatman, Peter T. Nelson, John T. Slevin, Larry B. Goldstein, Geert Jan Biessels, Florin Despa

Pharmacology and Nutritional Sciences Faculty Publications

OBJECTIVE: The brain blood vessels of patients with type 2 diabetes and dementia have deposition of amylin, an amyloidogenic hormone cosecreted with insulin. It is not known whether vascular amylin deposition is a consequence or a trigger of vascular injury. We tested the hypothesis that the vascular amylin deposits cause endothelial dysfunction and microvascular injury and are modulated by amylin transport in the brain via plasma apolipoproteins.

METHODS: Rats overexpressing amyloidogenic (human) amylin in the pancreas (HIP rats) and amylin knockout (AKO) rats intravenously infused with aggregated amylin were used for in vivo phenotyping. We also carried out biochemical analyses …

In Vivo Evaluation Of Stem Cell Aggregates On Osteochondral Regeneration., Banupriya Sridharan, Amy D. Laflin, Michael A. Holtz, Donna M. Pacicca, Nicholas K. Wischmeier, Michael S. Detamore

Manuscripts, Articles, Book Chapters and Other Papers

To date, many osteochondral regenerative approaches have utilized varied combinations of biocompatible materials and cells to engineer cartilage. Even in cell-based approaches, to date, no study has utilized stem cell aggregates alone for regenerating articular cartilage. Thus, the purpose of this study was to evaluate the performance of a novel stem cell-based aggregate approach in a fibrin carrier to regenerate osteochondral defects in the Sprague-Dawley rat trochlear groove model. Two different densities of rat bone marrow mesenchymal stem cell (rBMSC) aggregates were fabricated by the hanging drop technique. At 8 weeks, the cell aggregates supported the defects and served as …

Mdm2 Is Required For Survival And Growth Of P53-Deficient Cancer Cells., Kyle P Feeley, Clare M. Adams, Ramkrishna Mitra, Christine M. Eischen

Department of Cancer Biology Faculty Papers

p53 deletion prevents the embryonic lethality of normal tissues lacking Mdm2, suggesting that cells can survive without Mdm2 if p53 is also absent. Here we report evidence challenging this view, with implications for therapeutically targeting Mdm2. Deletion of Mdm2 in T-cell lymphomas or sarcomas lacking p53 induced apoptosis and G₂ cell-cycle arrest, prolonging survival of mice with these tumors. p53^-/- fibroblasts showed similar results, indicating that the effects of Mdm2 loss extend to pre-malignant cells. Mdm2 deletion in p53^-/- cells upregulated p53 transcriptional target genes that induce apoptosis and cell-cycle arrest. Mdm2 deletion also increased levels of …

Peripheral Inflammation, Apolipoprotein E4, And Amyloid-Β Interact To Induce Cognitive And Cerebrovascular Dysfunction, Felecia M. Marottoli, Yuriko Katsumata, Kevin P. Koster, Riya Thomas, David W. Fardo, Leon M. Tai

Biostatistics Faculty Publications

Cerebrovascular dysfunction is rapidly reemerging as a major process of Alzheimer’s disease (AD). It is, therefore, crucial to delineate the roles of AD risk factors in cerebrovascular dysfunction. While apolipoprotein E4 (APOE4), Amyloid-β (Aβ), and peripheral inflammation independently induce cerebrovascular damage, their collective effects remain to be elucidated. The goal of this study was to determine the interactive effect of APOE4, Aβ, and chronic repeated peripheral inflammation on cerebrovascular and cognitive dysfunction in vivo. EFAD mice are a well-characterized mouse model that express human APOE3 (E3FAD) or APOE4 (E4FAD) and overproduce human Aβ42 via expression of …

Targeting Antioxidant Enzyme Expression As A Therapeutic Strategy For Ischemic Stroke, Stephanie M. Davis, Keith R. Pennypacker

Center for Advanced Translational Stroke Science Faculty Publications

During ischemic stroke, neurons and glia are subjected to damage during the acute and neuroinflammatory phases of injury. Production of reactive oxygen species (ROS) from calcium dysregulation in neural cells and the invasion of activated immune cells are responsible for stroke-induced neurodegeneration. Scientists have failed thus far to identify antioxidant-based drugs that can enhance neural cell survival and improve recovery after stroke. However, several groups have demonstrated success in protecting against stroke by increasing expression of antioxidant enzymes in neural cells. These enzymes, which include but are not limited to enzymes in the glutathione peroxidase, catalase, and superoxide dismutase families, …

The Glia Response After Peripheral Nerve Injury: A Comparison Between Schwann Cells And Olfactory Ensheathing Cells And Their Uses For Neural Regenerative Therapies, Matthew J Barton, James St John, Alison Wright, Jenny Ekberg

Jenny Ekberg

The peripheral nervous system (PNS) exhibits a much larger capacity for regeneration than the central nervous system (CNS). One reason for this difference is the difference in glial cell types between the two systems. PNS glia respond rapidly to nerve injury by clearing debris from the injury site, supplying essential growth factors and providing structural support; all of which enhances neuronal regeneration. Thus, transplantation of glial cells from the PNS is a very promising therapy for injuries to both the PNS and the CNS. There are two key types of PNS glia: olfactory ensheathing cells (OECs), which populate the olfactory …

Nfatc2 Modulates Microglial Activation In The Aβpp/Ps1 Mouse Model Of Alzheimer's Disease, Gunjan D. Manocha, Atreyi Ghatak, Kendra L. Puig, Susan D. Kraner, Christopher M. Norris, Colin K. Combs

Pharmacology and Nutritional Sciences Faculty Publications

Alzheimer’s disease (AD) brains are characterized by fibrillar amyloid-β (Aβ) peptide containing plaques and associated reactive microglia. The proinflammatory phenotype of the microglia suggests that they may negatively affect disease course and contribute to behavioral decline. This hypothesis predicts that attenuating microglial activation may provide benefit against disease. Prior work from our laboratory and others has characterized a role for the transcription factor, nuclear factor of activated T cells (NFAT), in regulating microglial phenotype in response to different stimuli, including Aβ peptide. We observed that the NFATc2 isoform was the most highly expressed in murine microglia cultures, and inhibition or …

Zinc Transporters Ybtx And Znuabc Are Required For The Virulence Of Yersinia Pestis In Bubonic And Pneumonic Plague In Mice, Alexander G. Bobrov, Olga Kirillina, Marina Y. Fosso, Jacqueline D. Fetherston, M. Clarke Miller, Tiva T. Vancleave, Joseph A. Burlison, William K. Arnold, Matthew B. Lawrenz, Sylvie Garneau-Tsodikova, Robert D. Perry

Microbiology, Immunology, and Molecular Genetics Faculty Publications

A number of bacterial pathogens require the ZnuABC Zinc (Zn²⁺) transporter and/or a second Zn²⁺ transport system to overcome Zn²⁺ sequestration by mammalian hosts. Previously we have shown that in addition to ZnuABC, Yersinia pestis possesses a second Zn²⁺ transporter that involves components of the yersiniabactin (Ybt), siderophore-dependent iron transport system. Synthesis of the Ybt siderophore and YbtX, a member of the major facilitator superfamily, are both critical components of the second Zn²⁺ transport system. Here we demonstrate that a ybtX znu double mutant is essentially avirulent in mouse models of bubonic and pneumonic …

Sensory Processing In Autism Spectrum Disorders And Fragile X Syndrome-From The Clinic To Animal Models., D Sinclair, B Oranje, K A Razak, S J Siegel, S Schmid

Brain and Mind Institute Researchers' Publications

Brains are constantly flooded with sensory information that needs to be filtered at the pre-attentional level and integrated into endogenous activity in order to allow for detection of salient information and an appropriate behavioral response. People with Autism Spectrum Disorder (ASD) or Fragile X Syndrome (FXS) are often over- or under-reactive to stimulation, leading to a wide range of behavioral symptoms. This altered sensitivity may be caused by disrupted sensory processing, signal integration and/or gating, and is often being neglected. Here, we review translational experimental approaches that are used to investigate sensory processing in humans with ASD and FXS, and …