Digital Commons Network^™

Functional Genomics Reveals An Essential And Specific Role For Stat1 In Protection Of The Central Nervous System Following Herpes Simplex Virus Corneal Infection, Tracy J. Pasieka, Cristian Cilloniz, Victoria S. Carter, Pamela Rosato, Michael G. Katze, David A. Leib

Dartmouth Scholarship

Innate immune deficiencies result in a spectrum of severe clinical outcomes following infection. In particular, there is a strong association between loss of the signal transducer and activator of transcription (Stat) pathway, breach of the blood-brain barrier (BBB), and virus-induced neuropathology. The gene signatures that characterize resistance, disease, and mortality in the virus-infected nervous system have not been defined. Herpes simplex virus type 1 (HSV-1) is commonly associated with encephalitis in humans, and humans and mice lacking Stat1 display increased susceptibility to HSV central nervous system (CNS) infections. In this study, two HSV-1 strains were used, KOS (wild type [WT]), …

Effect Of Voluntary Exercise And Diet On The Unfolded Protein Response In The Brain Of Mice, Yu Ho Kim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The medical costs for many chronic diseases are increasing dramatically and placing a major financial burden on nations and individuals in both developed and developing countries. A number of chronic diseases, such as obesity, type 2 diabetes and some neurodegenerative diseases are all attenuated by a history of physical activity suggesting that they may be interconnected in some way. It has been suggested that cellular stress is a major factor promoting these chronic diseases.

Cellular stress occurs in a specific compartment within the cell, the endoplasmic reticulum, whose normal function is in the synthesis and folding of proteins into the …

Additive Functions In Boolean Models Of Gene Regulatory Network Modules, Christian Darabos, Ferdinando Ferdinando Di Cunto, Marco Tomassini, Jason H. Moore

Dartmouth Scholarship

Gene-on-gene regulations are key components of every living organism. Dynamical abstract models of genetic regulatory networks help explain the genome’s evolvability and robustness. These properties can be attributed to the structural topology of the graph formed by genes, as vertices, and regulatory interactions, as edges. Moreover, the actual gene interaction of each gene is believed to play a key role in the stability of the structure. With advances in biology, some effort was deployed to develop update functions in Boolean models that include recent knowledge. We combine real-life gene interaction networks with novel update functions in a Boolean model. We …

Rna-Sequencing Analysis From The Triceps Muscle Of Normal And Myostatin-Deficient Mice Using Various Tools, Richard Rodrigues

Theses

RNA-Sequencing technologies are being used to determine the single nucleotide polymorphisms, insertions, deletions and gene expression. The purpose of this study was to analyze the effect of myostatin in the triceps muscles of mice using 65 bases single-end RNA-Sequencing data from the Illumina platform. Another aim was to analyze alternative splicing events for differentially expressed genes in the above data. Finally, commercially available and open source software packages were compared for their splice junction detection abilities. CASAVA was used for determining the exon, gene and splice junction counts. Partek Genomic Suite was used to perform a two-way analysis of variance …

An Engineered Approach To Stem Cell Culture: Automating The Decision Process For Real-Time Adaptive Subculture Of Stem Cells, Dai Fei Elmer Ker, Lee E. Weiss, Silvina N. Junkers, Mei Chen, Zhaozheng Yin, Mike F. Sandbothe, Seungil Huh, Sungeun Eom, Ryoma Bise, Elvira Osuna-Highley, Takeo Kanade, Phil Gordon Campbell

Computer Science Faculty Research & Creative Works

Current cell culture practices are dependent upon human operators and remain laborious and highly subjective, resulting in large variations and inconsistent outcomes, especially when using visual assessments of cell confluency to determine the appropriate time to subculture cells. Although efforts to automate cell culture with robotic systems are underway, the majority of such systems still require human intervention to determine when to subculture. Thus, it is necessary to accurately and objectively determine the appropriate time for cell passaging. Optimal stem cell culturing that maintains cell pluripotency while maximizing cell yields will be especially important for efficient, cost-effective stem cell-based therapies. …

Differential Il-21 Signaling In Apcs Leads To Disparate Th17 Differentiation In Diabetes-Susceptible Nod And Diabetes-Resistant Nod.Idd3 Mice., Sue M. Liu, David H. Lee, Jenna M. Sullivan, Denise Chung, Anneli Jäger, Bennett O V. Shum, Nora E. Sarvetnick, Ana C. Anderson, Vijay K. Kuchroo

Journal Articles: Regenerative Medicine

Type 1 diabetes (T1D) is an autoimmune disease that shows familial aggregation in humans and likely has genetic determinants. Disease linkage studies have revealed many susceptibility loci for T1D in mice and humans. The mouse T1D susceptibility locus insulin-dependent diabetes susceptibility 3 (Idd3), which has a homologous genetic interval in humans, encodes cytokine genes Il2 and Il21 and regulates diabetes and other autoimmune diseases; however, the cellular and molecular mechanisms of this regulation are still being elucidated. Here we show that T cells from NOD mice produce more Il21 and less Il2 and exhibit enhanced Th17 cell generation compared with …

Early Exposure To Paraquat Sensitizes Dopaminergic Neurons To Subsequent Silencing Of Pink1 Gene Expression In Mice., Hongxia Zhou, Cao Huang, Jianbin Tong, Xugang Xia

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Environmental exposure, genetic modification, and aging are considered risky for Parkinson's disease (PD). How these risk factors cooperate to induce progressive neurodegeneration in PD remains largely unknown. Paraquat is an herbicide commonly used for weed and grass control. Exposure to paraquat is associated with the increased incidence of PD. In contrast to familial PD, most sporadic PD cases do not have genetic mutation, but may suffer from partial dysfunction of neuron-protective genes as aging. Using conditional transgenic RNAi, we showed that temporal silencing of PINK1 expression in adult mice increased striatal dopamine, the phenotype that could not be induced by …

Reversal Of Glial And Neurovascular Markers Of Unhealthy Brain Aging By Exercise In Middle-Aged Female Mice, Caitlin S. Latimer, James L. Searcy, Michael T. Bridges, Lawrence D. Brewer, Jelena Popović, Eric M. Blalock, Philip W. Landfield, Olivier Thibault, Nada M. Porter

Pharmacology and Nutritional Sciences Faculty Publications

Healthy brain aging and cognitive function are promoted by exercise. The benefits of exercise are attributed to several mechanisms, many which highlight its neuroprotective role via actions that enhance neurogenesis, neuronal morphology and/or neurotrophin release. However, the brain is also composed of glial and vascular elements, and comparatively less is known regarding the effects of exercise on these components in the aging brain. Here, we show that aerobic exercise at mid-age decreased markers of unhealthy brain aging including astrocyte hypertrophy, a hallmark of brain aging. Middle-aged female mice were assigned to a sedentary group or provided a running wheel for …

Thrombospondin1 Deficiency Reduces Obesity-Associated Inflammation And Improves Insulin Sensitivity In A Diet-Induced Obese Mouse Model, Yanzhang Li, Xiaopeng Tong, Courtney Rumala, Kate Clemons, Shuxia Wang

Graduate Center for Nutritional Sciences Faculty Publications

BACKGROUND: Obesity is prevalent worldwide and is associated with insulin resistance. Advanced studies suggest that obesity-associated low-grade chronic inflammation contributes to the development of insulin resistance and other metabolic complications. Thrombospondin 1 (TSP1) is a multifunctional extracellular matrix protein that is up-regulated in inflamed adipose tissue. A recent study suggests a positive correlation of TSP1 with obesity, adipose inflammation, and insulin resistance. However, the direct effect of TSP1 on obesity and insulin resistance is not known. Therefore, we investigated the role of TSP1 in mediating obesity-associated inflammation and insulin resistance by using TSP1 knockout mice.

METHODOLOGY/PRINCIPAL FINDINGS: Male TSP1-/- mice …

Splice Variant–Specific Cellular Function Of The Formin Inf2 In Maintenance Of Golgi Architecture, Vinay Ramabhadran, Farida Korobova, Gilbert J. Rahme, Henry N. Higgs

Dartmouth Scholarship

INF2 is a unique formin that can both polymerize and depolymerize actin filaments. Mutations in INF2 cause the kidney disease focal and segmental glomerulosclerosis. INF2 can be expressed as two C-terminal splice variants: CAAX and non-CAAX. The CAAX isoform contains a C-terminal prenyl group and is tightly bound to endoplasmic reticulum (ER). The localization pattern and cellular function of the non-CAAX isoform have not been studied. Here we find that the two isoforms are expressed in a cell type-dependent manner, with CAAX predominant in 3T3 fibroblasts and non-CAAX predominant in U2OS, HeLa, and Jurkat cells. Although INF2-CAAX is ER localized …

Demasculinization And Feminization Of Male Gonads By Atrazine: Consistent Effects Across Vertebrate Classes, Krista A. Mccoy

Integrative Biology Faculty and Staff Publications

Atrazine is the most commonly detected pesticide contaminant of ground water, surface water, and precipitation. Atrazine is also an endocrine disruptor that, among other effects, alters male reproductive tissues when animals are exposed during development. Here, we apply the nine so-called “Hill criteria” (Strength, Consistency, Specificity, Temporality, Biological Gradient, Plausibility, Coherence, Experiment, and Analogy) for establishing cause–effect relationships to examine the evidence for atrazine as an endocrine disruptor that demasculinizes and feminizes the gonads of male vertebrates. We present experimental evidence that the effects of atrazine on male development are consistent across all vertebrate classes examined and we present a …

Reduced Cardioprotective Action Of Adiponectin In High-Fat Diet-Induced Type Ii Diabetic Mice And Its Underlying Mechanisms., Wei Yi, Yang Sun, Erhe Gao, Xufeng Wei, Wayne Bond Lau, Qijun Zheng, Yajing Wang, Yuexing Yuan, Xiaoliang Wang, Ling Tao, Rong Li, Walter Koch, Xin-Liang Ma

Department of Emergency Medicine Faculty Papers

Diabetes exacerbates ischemic heart disease morbidity and mortality via incompletely understood mechanisms. Although adiponectin (APN) reduces myocardial ischemia/reperfusion (MI/R) injury in nondiabetic animals, whether APN's cardioprotective actions are altered in diabetes, a pathologic condition with endogenously reduced APN, has never been investigated. High-fat diet (HD)-induced diabetic mice and normal diet (ND) controls were subjected to MI via coronary artery ligation, and given vehicle or APN globular domain (gAPN, 2 μg/g) 10 min before reperfusion. Compared to ND mice (where gAPN exerted pronounced cardioprotection), HD mice manifested greater MI/R injury, and a tripled gAPN dose was requisite to achieve cardioprotective extent …

Differential Interactions Of The Formins Inf2, Mdia1, And Mdia2 With Microtubules, Jeremie Gaillard, Bvinay Ramabhadran, Emmanuelle Neumanne, Pinar Gurel, Laurent Blanchoin, Marylin Vantard, Henry N. Higgs

Dartmouth Scholarship

A number of cellular processes use both microtubules and actin filaments, but the molecular machinery linking these two cytoskeletal elements remains to be elucidated in detail. Formins are actin-binding proteins that have multiple effects on actin dynamics, and one formin, mDia2, has been shown to bind and stabilize microtubules through its formin homology 2 (FH2) domain. Here we show that three formins, INF2, mDia1, and mDia2, display important differences in their interactions with microtubules and actin. Constructs containing FH1, FH2, and C-terminal domains of all three formins bind microtubules with high affinity (K(d) < 100 nM). However, only mDia2 binds microtubules at 1:1 stoichiometry, with INF2 and mDia1 showing saturating binding at approximately 1:3 (formin dimer:tubulin dimer). INF2-FH1FH2C is a potent microtubule-bundling protein, an effect that results in a large reduction in catastrophe rate. In contrast, neither mDia1 nor mDia2 is a potent microtubule bundler. The C-termini of mDia2 and INF2 have different functions in microtubule interaction, with mDia2's C-terminus required for high-affinity binding and INF2's C-terminus required for bundling. mDia2's C-terminus directly binds microtubules with submicromolar affinity. These formins also differ in their abilities to bind actin and microtubules simultaneously. Microtubules strongly inhibit actin polymerization by mDia2, whereas they moderately inhibit mDia1 and have no effect on INF2. Conversely, actin monomers inhibit microtubule binding/bundling by INF2 but do not affect mDia1 or mDia2. These differences in interactions with microtubules and actin suggest differential function in cellular processes requiring both cytoskeletal elements.

Strain-Dependent Variation In The Early Transcriptional Response To Cns Injury Using A Cortical Explant System, David J. Graber, Brent T. Harris, William F. Hickey

Dartmouth Scholarship

While it is clear that inbred strains of mice have variations in immunological responsiveness, the influence of genetic background following tissue damage in the central nervous system is not fully understood. A cortical explant system was employed as a model for injury to determine whether the immediate transcriptional response to tissue resection revealed differences among three mouse strains. Immunological mRNAs were measured in cerebral cortex from SJL/J, C57BL/6J, and BALB/cJ mice using real time RT-PCR. Freshly isolated cortical tissue and cortical sections incubated in explant medium were examined. Levels of mRNA, normalized to β-actin, were compared using one way analysis …

Rhythmic Leptin Is Required For Weight Gain From Circadian Desynchronized Feeding In The Mouse, Deanna M. Arble, Martha H. Vitaterna, Fred W. Turek

Biological Sciences Faculty Research and Publications

The neuroendocrine and metabolic effects of leptin have been extensively researched since the discovery, and the later identification, of the leptin gene mutated within the ob/ob mouse. Leptin is required for optimal health in a number of physiological systems (e.g. fertility, bone density, body weight regulation). Despite the extensive leptin literature and many observations of leptin’s cyclical pattern over the 24-hour day, few studies have specifically examined how the circadian rhythm of leptin may be essential to leptin signaling and health. Here we present data indicating that a rhythmic leptin profile (e.g. 1 peak every 24 hours) leads to excessive …

In Vivo Microdialysis Reveals Age-Dependent Decrease Of Brain Interstitial Fluid Tau Levels In P301s Human Tau Transgenic Mice, Kaoru Yamada, John R. Cirrito, Floy R. Stewart, Hong Jiang, Mary Beth Finn, Brandon B. Holmes, Lester I. Binder, Eva-Maria Mandelkow, Marc I. Diamond, Virginia M.-Y. Lee, David M. Holtzman

Open Access Publications

Although tau is a cytoplasmic protein, it is also found in brain extracellular fluids, e.g., CSF. Recent findings suggest that aggregated tau can be transferred between cells and extracellular tau aggregates might mediate spread of tau pathology. Despite these data, details of whether tau is normally released into the brain interstitial fluid (ISF), its concentration in ISF in relation to CSF, and whether ISF tau is influenced by its aggregation are unknown. To address these issues, we developed a microdialysis technique to analyze monomeric ISF tau levels within the hippocampus of awake, freely moving mice. We detected tau in ISF …

Activation Of Matrix Metalloproteinases Following Anti-Aβ Immunotherapy; Implications For Microhemorrhage Occurrence, Donna M. Wilcock, Dave Morgan, Marcia N. Gordon, Tiffany L. Taylor, Lisa A. Ridnour, David A. Wink, Carol A. Colton

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Anti-Aβ immunotherapy is a promising approach to the prevention and treatment of Alzheimer's disease (AD) currently in clinical trials. There is extensive evidence, both in mice and humans that a significant adverse event is the occurrence of microhemorrhages. Also, vasogenic edema was reported in phase 2 of a passive immunization clinical trial. In order to overcome these vascular adverse effects it is critical that we understand the mechanism(s) by which they occur.

METHODS: We have examined the matrix metalloproteinase (MMP) protein degradation system in two previously published anti-Aβ immunotherapy studies. The first was a passive immunization study in which …

Toxoplasma Gondii Rhoptry Kinase Rop16 Activates Stat3 And Stat6 Resulting In Cytokine Inhibition And Arginase-1-Dependent Growth Control, Barbara A. Butcher, Barbara A. Fox, Leah M. Rommereim, Sung Guk Kim, Kirk J. Maurer, Felix Yarovinsky, De'broski R. Herbert, David J. Bzik, Eric Y. Denkers

Dartmouth Scholarship

The ROP16 kinase of Toxoplasma gondii is injected into the host cell cytosol where it activates signal transducer and activator of transcription (STAT)-3 and STAT6. Here, we generated a ROP16 deletion mutant on a Type I parasite strain background, as well as a control complementation mutant with restored ROP16 expression. We investigated the biological role of the ROP16 molecule during T. gondii infection. Infection of mouse bone marrow-derived macrophages with rop16-deleted (ΔROP16) parasites resulted in increased amounts of IL-12p40 production relative to the ROP16-positive RH parental strain. High level IL-12p40 production in ΔROP16 infection was dependent on the host …

Bioluminescent Imaging Reveals Divergent Viral Pathogenesis In Two Strains Of Stat1-Deficient Mice, And In Αßγ Interferon Receptor-Deficient Mice, Tracy Jo Pasieka, Lynne Collins, Megan A. O'Connor, Yufei Chen, Zachary M. Parker, Brent L. Berwin, David R. Piwnica-Worms, David A. Leib

Dartmouth Scholarship

Pivotal components of the IFN response to virus infection include the IFN receptors (IFNR), and the downstream factorsignal transducer and activator of transcription 1 (Stat1). Mice deficient for Stat1 and IFNR (Stat12/2 and IFNaßcR2/2 mice) lack responsiveness to IFN and exhibit high sensitivity to various pathogens. Here we examined herpes simplex virus type 1 (HSV-1) pathogenesis in Stat12/2 mice and in IFNaßcR2/2 mice following corneal infection and bioluminescent imaging. Two divergent and paradoxical patterns of infection were observed. Mice with an N-terminal deletion in Stat1 (129Stat12/2(N-term)) had transient infection of the liver and spleen, but succumbed to encephalitis by day …

An Evolutionarily Conserved Rit Gtpase-P38 Mapk Signaling Pathway Mediates Oxidative Stress Resistance, Weikang Cai, Jennifer L. Rudolph, Susan M. W. Harrison, Ling Jin, Aubrey L. Frantz, Douglas A. Harrison, Douglas A. Andres

Molecular and Cellular Biochemistry Faculty Publications

Ras-related small GTP-binding proteins control a wide range of cellular processes by regulating a variety of effector pathways, including prominent roles in the control of mitogen-activated protein kinase (MAPK) cascades. Although the regulatory role(s) for many Ras family GTPases are well established, the physiological function for the Rit/Rin subfamily has been lacking. Here, using both knockout mice and Drosophila models, we demonstrate an evolutionarily conserved role for Rit subfamily GTPases (mammalian Rit and Rin, and the Drosophila RIC homologue) in governing survival in response to oxidative stress. Primary embryonic fibroblasts derived from Rit knockout mice display increased apoptosis and selective …

Dynamic Alteration Of Adiponectin/Adiponectin Receptor Expression And Its Impact On Myocardial Ischemia/Reperfusion In Type 1 Diabetic Mice., Yanzhuo Ma, Yi Liu, Shaowei Liu, Yan Qu, Rutao Wang, Chenhai Xia, Haifeng Pei, Kun Lian, Tao Yin, Xiaoyan Lu, Lu Sun, Lu Yang, Yanjie Cao, Wayne Bond Lau, Erhe Gao, Haichang Wang, Ling Tao

Department of Emergency Medicine Faculty Papers

The present study determined the dynamic change of adiponectin (APN, a cardioprotective adipokine), its receptor expression, and their impact upon myocardial ischemia/reperfusion (MI/R) injury during type 1 diabetes mellitus (T1DM) progression, and involved underlying mechanisms. Diabetic state was induced in mice via multiple intraperitoneal injections of low-dose streptozotocin. The dynamic change of plasma APN concentration and cardiac APN receptor-1 and -2 (AdipoR1/2) expression were assessed immediately after diabetes onset (0 wk) and 1, 3, 5, and 7 wk thereafter. Indicators of MI/R injury (infarct size, apoptosis, and LDH release) were determined at 0, 1, and 7 wk of DM duration. …

Type Ii Toxoplasma Gondii Ku80 Knockout Strains Enable Functional Analysis Of Genes Required For Cyst Development And Latent Infection, Barbara A. Fox, Alejandra Falla, Leah M. Rommereim, Tadakimi Tomita

Dartmouth Scholarship

Type II Toxoplasma gondii KU80 knockouts (Δku80) deficient in nonhomologous end joining were developed to delete the dominant pathway mediating random integration of targeting episomes. Gene targeting frequency in the type II Δku80 Δhxgprt strain measured at the orotate (OPRT) and the uracil (UPRT) phosphoribosyltransferase loci was highly efficient. To assess the potential of the type II Δku80 Δhxgprt strain to examine gene function affecting cyst biology and latent stages of infection, we targeted the deletion of four parasite antigen genes (GRA4, GRA6, ROP7, and tgd057 …

Altered Toll-Like Receptor 2-Mediated Endotoxin Tolerance Is Related To Diminished Interferon Beta Production., Ss Zaric, Wa Coulter, Ce Shelburne, Cr Fulton, Ms Zaric, A Scott, Mj Lappin, Dc Fitzgerald, Cr Irwin, Cc Taggart

Peninsula Dental School

Induction of endotoxin tolerance leads to a reduced inflammatory response after repeated challenge by LPS and is important for resolution of inflammation and prevention of tissue damage. Enterobacterial LPS is recognized by the TLR4 signaling complex, whereas LPS of some non-enterobacterial organisms is capable of signaling independently of TLR4 utilizing TLR2-mediated signal transduction instead. In this study we report that Porphyromonas gingivalis LPS, a TLR2 agonist, fails to induce a fully endotoxin tolerant state in a human monocytic cell line (THP-1) and mouse bone marrow-derived macrophages. In contrast to significantly decreased production of human IL-8 and TNF-α and, in mice, …

Metastasis Of Tumor Cells Is Enhanced Bydownregulation Of Bit1, Priya Prakash Karmali, Chris Brunquell, Shubha Kale Ireland, Erkki Ruostlahti, Hau Tram, Hector Biliran

Faculty and Staff Publications

Abstract Background: Resistance to anoikis, which is defined as apoptosis induced by loss of integrin-mediated cell attachment to the extracellular matrix, is a determinant of tumor progression and metastasis. We have previously identified the mitochondrial Bit1 (Bcl-2 inhibitor of transcription) protein as a novel anoikis effector whose apoptotic function is independent from caspases and is uniquely controlled by integrins. In this report, we examined the possibility that Bit1 is suppressed during tumor progression and that Bit1 downregulation may play a role in tumor metastasis. Methodology/Principal Findings: Using a human breast tumor tissue array, we found that Bit1 expression is suppressed …

Monoclonal Antibodies Recognizing The Non-Tandem Repeat Regions Of The Human Mucin Muc4 In Pancreatic Cancer., Maneesh Jain, Ganesh Venkatraman, Nicolas Moniaux, Sukhwinder Kaur, Sushil Kumar, Subhankar Chakraborty, Grish C. Varshney, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

The MUC4 mucin is a high molecular weight, membrane-bound, and highly glycosylated protein. It is a multi-domain protein that is putatively cleaved into a large mucin-like subunit (MUC4α) and a C-terminal growth-factor like subunit (MUC4β). MUC4 plays critical roles in physiological and pathological conditions and is aberrantly overexpressed in several cancers, including those of the pancreas, cervix, breast and lung. It is also a potential biomarker for the diagnosis, prognosis and progression of several malignancies. Further, MUC4 plays diverse functional roles in cancer initiation and progression as evident from its involvement in oncogenic transformation, proliferation, inhibition of apoptosis, motility and …

Ros-Drill Automation: Visual Feedback Control And Rotational Motion Tracking, Jhon F. Diaz

Master's Theses

ICSI (intra-cytoplasmic sperm injection) has attracted research interest from both biological and engineering groups. The technology is constantly evolving to perform this procedure with precision and speed. One such development is the contribution of this thesis. We focus on a relatively recent procedure called Ros-Drill^© (rotationally oscillating drill), of which the early versions have already been effectively utilized for the mice. In the first part, we present a procedure to automate a critical part of the operation: initiation of the rotational oscillation, Visual feedback is used to track the pipette tip. Predetermined species-specific penetration depth is successfully utilized …

Cd40 Is Essential In The Upregulation Of Traf Proteins And Nf-Kappab-Dependent Proinflammatory Gene Expression After Arterial Injury, Zifang Song, Rong Jin, Shiyong Yu, Joshua J. Rivet, Susan S. Smyth, Anil Nanda, D. Neil Granger, Guohong Li

Internal Medicine Faculty Publications

Despite extensive investigations, restenosis, which is characterized primarily by neointima formation, remains an unsolved clinical problem after vascular interventions. A recent study has shown that CD40 signaling through TNF receptor associated factor 6 (TRAF6) plays a key role in neointima formation after carotid artery injury; however, underlying mechanisms are not clearly elucidated. Because neointima formation may vary significantly depending on the type of injury, we first assessed the effect of CD40 deficiency on neointima formation in 2 injury models, carotid artery ligation and femoral artery denudation injury. Compared with wild-type mice, CD40 deficiency significantly reduced neointima formation and lumen stenosis …

Serum- And Glucocorticoid-Induced Kinase 3 In Recycling Endosomes Mediates Acute Activation Of Na+/H+ Exchanger Nhe3 By Glucocorticoids, Peijian He, Sei-Jung Lee, Songbai Lin, Ursula Seidler, Florian Lang, Geza Fejes-Toth, Aniko Naray-Fejes-Toth, C. Chris Yun

Dartmouth Scholarship

Na(+)/H(+) exchanger 3 (NHE3) is the major Na(+) transporter in the intestine. Serum- and glucocorticoid-induced kinase (SGK) 1 interacts with NHE regulatory factor 2 (NHERF2) and mediates activation of NHE3 by dexamethasone (Dex) in cultured epithelial cells. In this study, we compared short-term regulation of NHE3 by Dex in SGK1-null and NHERF2-null mice. In comparison to wild-type mice, loss of SGK1 or NHERF2 significantly attenuated regulation of NHE3 by Dex but did not completely obliterate the effect. We show that transfection of SGK2 or SGK3 in PS120 cells resulted in robust activation of NHE3 by Dex. However, unlike SGK1 or …

Tlr4 Mutation Reduces Microglial Activation, Increases Aβ Deposits And Exacerbates Cognitive Deficits In A Mouse Model Of Alzheimer's Disease, Min Song, Jingji Jin, Jinghong Kou, Abhinandan Pattanayak, Jamaal Rehman, Hong-Duck Kim, Ken-Ichiro Fukuchi

NYMC Faculty Publications

BACKGROUND: Amyloid plaques, a pathological hallmark of Alzheimer's disease (AD), are accompanied by activated microglia. The role of activated microglia in the pathogenesis of AD remains controversial: either clearing Aβ deposits by phagocytosis or releasing proinflammatory cytokines and cytotoxic substances. Microglia can be activated via toll-like receptors (TLRs), a class of pattern-recognition receptors in the innate immune system. We previously demonstrated that an AD mouse model homozygous for a loss-of-function mutation of TLR4 had increases in Aβ deposits and buffer-soluble Aβ in the brain as compared with a TLR4 wild-type AD mouse model at 14-16 months of age. However, it …

Protein Kinase Cδ And C-Abl Kinase Are Required For Transforming Growth Factor Β Induction Of Endothelial-Mesenchymal Transition In Vitro., Zhaodong Li, Sergio A. Jimenez

Department of Medicine Faculty Papers

OBJECTIVE: The origin of the mesenchymal cells responsible for the intimal fibrosis in systemic sclerosis (SSc) has not been fully identified. The present study was undertaken to investigate whether subendothelial mesenchymal cells may emerge through transdifferentiation of endothelial cells (ECs) into myofibroblasts via endothelial-mesenchymal transition (EndoMT) in vitro and to explore the signaling pathways involved in this process.

METHODS: Primary mouse pulmonary ECs isolated by immunomagnetic methods with sequential anti-CD34 and anti-CD102 antibody selection were cultured in monolayers. Cell morphology and diacetylated low-density lipoprotein uptake assays confirmed their EC characteristics. The induction of EndoMT was assessed by determination of α-smooth …