Medicine and Health Sciences Commons^™

The P38alpha Mitogen-Activated Protein Kinase Limits The Cns Proinflammatory Cytokine Response To Systemic Lipopolysaccharide, Potentially Through An Il-10 Dependent Mechanism, Adam D. Bachstetter, Bin Xing, Linda J. Van Eldik

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: The p38α mitogen-activated protein kinase (MAPK) is a well-characterized intracellular kinase involved in the overproduction of proinflammatory cytokines from glia. As such, p38α appears to be a promising therapeutic target for neurodegenerative diseases associated with neuroinflammation. However, the in vivo role of p38α in cytokine production in the CNS is poorly defined, and prior work suggests that p38α may be affecting a yet to be identified negative feedback mechanism that limits the acute, injury-induced proinflammatory cytokine surge in the CNS.

METHODS: To attempt to define this negative feedback mechanism, we used two in vitro and two in vivo models …

Ticagrelor: Pharmacokinetics, Pharmacodynamics, Clinical Efficacy, And Safety., Paul P. Dobesh, Julie H. Oestreich

Journal Articles: Pharmacy Practice

Dual antiplatelet therapy, composed of aspirin plus a P2Y12 -receptor antagonist, is the cornerstone of treatment for patients with acute coronary syndrome (ACS). A number of U.S. Food and Drug Administration-approved P2Y12 -receptor antagonists are available for treating patients with ACS, including the thienopyridine compounds clopidogrel and prasugrel. Ticagrelor, the first of a new class of antiplatelet agents, is a noncompetitive, direct-acting P2Y12 -receptor antagonist. Unlike the thienopyridine compounds, ticagrelor does not require metabolism for activity. Also, whereas clopidogrel and prasugrel are irreversible inhibitors of the P2Y12 receptor, ticagrelor binds reversibly to inhibit receptor signaling and subsequent platelet activation. In …

Ct Perfusion Imaging As An Early Biomarker Of Differential Response To Stereotactic Radiosurgery In C6 Rat Gliomas, Timothy Pok Chi Yeung, Maher Kurdi, Yong Wang, Baraa Al-Khazraji, Laura Morrison, Lisa Hoffman, Dwayne Jackson, Cathie Crukley, Ting-Yim Lee, Glenn Bauman, Slav Yartsev

Medical Biophysics Publications

BACKGROUND: The therapeutic efficacy of stereotactic radiosurgery for glioblastoma is not well understood, and there needs to be an effective biomarker to identify patients who might benefit from this treatment. This study investigated the efficacy of computed tomography (CT) perfusion imaging as an early imaging biomarker of response to stereotactic radiosurgery in a malignant rat glioma model.

METHODS: Rats with orthotopic C6 glioma tumors received either mock irradiation (controls, N = 8) or stereotactic radiosurgery (N = 25, 12 Gy in one fraction) delivered by Helical Tomotherapy. Twelve irradiated animals were sacrificed four days after stereotactic radiosurgery to assess acute …

Developmental Stress, Condition, And Birdsong: A Case Study In Song Sparrows., Kim L Schmidt, Elizabeth A Macdougall-Shackleton, Shawn P Kubli, Scott A Macdougall-Shackleton

Brain and Mind Institute Researchers' Publications

Sexual-selection theory posits that ornaments and displays can reflect a signaler's condition, which in turn is affected both by recent and developmental conditions. Moreover, developmental conditions can induce correlations between sexually selected and other traits if both types of traits exhibit developmental phenotypic plasticity in response to stressors. Thus, sexually selected traits may reflect recent and/or developmental characteristics of signalers. Here, we review data on the relationships between birdsong, a sexually selected trait, and developmental and current condition of birds from a long-term study of a population of song sparrows (Melospiza melodia). Field studies of free-living birds indicate that the …

Systematic Review Of Potential Health Risks Posed By Pharmaceutical, Occupational And Consumer Exposures To Metallic And Nanoscale Aluminum, Aluminum Oxides, Aluminum Hydroxide And Its Soluble Salts, Calvin C. Willhite, Nataliya A. Karyakina, Robert A. Yokel, Nagarajkumar Yenugadhati, Thomas M. Wisniewski, Ian M. F. Arnold, Franco Momoli, Daniel Krewski

Pharmaceutical Sciences Faculty Publications

Aluminum (Al) is a ubiquitous substance encountered both naturally (as the third most abundant element) and intentionally (used in water, foods, pharmaceuticals, and vaccines); it is also present in ambient and occupational airborne particulates. Existing data underscore the importance of Al physical and chemical forms in relation to its uptake, accumulation, and systemic bioavailability. The present review represents a systematic examination of the peer-reviewed literature on the adverse health effects of Al materials published since a previous critical evaluation compiled by Krewski et al. (2007).

Challenges encountered in carrying out the present review reflected the experimental use of different physical …

Ethanol-Induced Oxidant Stress Modulates Hepatic Autophagy And Proteasome Activity., Terrence M. Donohue, Paul G. Thomes

Journal Articles: Biochemistry & Molecular Biology

In this review, we describe research findings on the effects of alcohol exposure on two major catabolic systems in liver cells: the ubiquitin-proteasome system (UPS) and autophagy. These hydrolytic systems are not unique to liver cells; they exist in all eukaryotic tissues and cells. However, because the liver is the principal site of ethanol metabolism, it sustains the greatest damage from heavy drinking. Thus, the focus of this review is to specifically describe how ethanol oxidation modulates the activities of the UPS and autophagy and the mechanisms by which these changes contribute to the pathogenesis of alcohol-induced liver injury. Here, …

Large-Scale Identification Of Chemically Induced Mutations In Drosophila Melanogaster, Nele A Haelterman, Lichun Jiang, Yumei Li, Vafa Bayat, Hector Sandoval, Berrak Ugur, Kai Li Tan, Ke Zhang, Danqing Bei, Bo Xiong, Wu-Lin Charng, Theodore Busby, Adeel Jawaid, Gabriela David, Manish Jaiswal, Koen J T Venken, Shinya Yamamoto, Rui Chen, Hugo J Bellen

Faculty, Staff and Students Publications

Forward genetic screens using chemical mutagens have been successful in defining the function of thousands of genes in eukaryotic model organisms. The main drawback of this strategy is the time-consuming identification of the molecular lesions causative of the phenotypes of interest. With whole-genome sequencing (WGS), it is now possible to sequence hundreds of strains, but determining which mutations are causative among thousands of polymorphisms remains challenging. We have sequenced 394 mutant strains, generated in a chemical mutagenesis screen, for essential genes on the Drosophila X chromosome and describe strategies to reduce the number of candidate mutations from an average of …

Myeloid Derived Hypoxia Inducible Factor 1-Alpha Is Required For Protection Against Pulmonary Aspergillus Fumigatus Infection, Kelly M. Shepardson, Anupam Jhingran, Alayna Caffrey, Joshua J. Obar, Benjamin T. Suratt, Brent L. Berwin, Tobias M. Hohl, Robert A. Cramer

Dartmouth Scholarship

Hypoxia inducible factor 1α (HIF1α) is the mammalian transcriptional factor that controls metabolism, survival, and innate immunity in response to inflammation and low oxygen. Previous work established that generation of hypoxic microenvironments occurs within the lung during infection with the human fungal pathogen Aspergillus fumigatus. Here we demonstrate that A. fumigatus stabilizes HIF1α protein early after pulmonary challenge that is inhibited by treatment of mice with the steroid triamcinolone. Utilizing myeloid deficient HIF1α mice, we observed that HIF1α is required for survival and fungal clearance early following pulmonary challenge with A. fumigatus. Unlike previously reported research with bacterial …

Transformation Of Human Cathelicidin Ll-37 Into Selective, Stable, And Potent Antimicrobial Compounds., Guangshun Wang, Mark L. Hanke, Biswajit Mishra, Tamara Lushnikova, Cortney E. Heim, Vinai Chittezham Thomas, Kenneth W. Bayles, Tammy Kielian

Journal Articles: Pathology and Microbiology

This Letter reports a family of novel antimicrobial compounds obtained by combining peptide library screening with structure-based design. Library screening led to the identification of a human LL-37 peptide resistant to chymotrypsin. This d-amino-acid-containing peptide template was active against Escherichia coli but not methicillin-resistant Staphylococcus aureus (MRSA). It possesses a unique nonclassic amphipathic structure with hydrophobic defects. By repairing the hydrophobic defects, the peptide (17BIPHE2) gained activity against the ESKAPE pathogens, including Enterococcus faecium, S. aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa, and Enterobacter species. In vitro, 17BIPHE2 could disrupt bacterial membranes and bind to DNA. In vivo, the peptide …

Dimethyl Sulfoxide Damages Mitochondrial Integrity And Membrane Potential In Cultured Astrocytes, Chan Yuan, Junying Gao, Jichao Guo, Lei Bai, Charles Marshall, Zhiyou Cai, Linmei Wang, Ming Xiao

Center of Excellence in Rural Health Faculty Publications

Dimethyl sulfoxide (DMSO) is a polar organic solvent that is used to dissolve neuroprotective or neurotoxic agents in neuroscience research. However, DMSO itself also has pharmacological and pathological effects on the nervous system. Astrocytes play a central role in maintaining brain homeostasis, but the effect and mechanism of DMSO on astrocytes has not been studied. The present study showed that exposure of astrocyte cultures to 1% DMSO for 24 h did not significantly affect cell survival, but decreased cell viability and glial glutamate transporter expression, and caused mitochondrial swelling, membrane potential impairment and reactive oxygen species production, and subsequent cytochrome …

The Distribution Pattern Of Halicephalobus Gingivalis In A Horse Is Suggestive Of A Haematogenous Spread Of The Nematode, Christina Henneke, Anna Jespersen, Stine Jacobsen, Martin K. Nielsen, Fintan Mcevoy, Henrik E. Jensen

Veterinary Science Faculty Publications

The majority of Halicephalobus gingivalis-infections in horses have been fatal and are usually not diagnosed before necropsy. Therefore, knowledge about the nematode and the pathogenesis of infection in horses is limited. This has resulted in an on-going discussion about the port of entry and subsequent dissemination of H. gingivalis within the host. The present case of H. gingivalis-infection in a horse was diagnosed ante mortem. Post mortem findings, the distribution pattern of H. gingivalis nematodes in the brain, a high prevalence of inflammation in close relation to blood vessels, and the presence of the nematode in multiple organs …

Calcineurin And Glial Signaling: Neuroinflammation And Beyond, Jennifer L. Furman, Christopher M. Norris

Sanders-Brown Center on Aging Faculty Publications

Similar to peripheral immune/inflammatory cells, neuroglial cells appear to rely on calcineurin (CN) signaling pathways to regulate cytokine production and cellular activation. Several studies suggest that harmful immune/inflammatory responses may be the most impactful consequence of aberrant CN activity in glial cells. However, newly identified roles for CN in glutamate uptake, gap junction regulation, Ca²⁺ dyshomeostasis, and amyloid production suggest that CN's influence in glia may extend well beyond neuroinflammation. The following review will discuss the various actions of CN in glial cells, with particular emphasis on astrocytes, and consider the implications for neurologic dysfunction arising with aging, injury, …

Unbiased Analysis Of Pancreatic Cancer Radiation Resistance Reveals Cholesterol Biosynthesis As A Novel Target For Radiosensitisation., Joshua J. Souchek, Michael J. Baine, Chi Lin, Satyanarayana Rachagani, Suprit Gupta, Sukhwinder Kaur, K Lester, D Zheng, S Chen, Lynette Smith, A Lazenby, Sonny L. Johansson, Maneesh Jain, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND: Despite its promise as a highly useful therapy for pancreatic cancer (PC), the addition of external beam radiation therapy to PC treatment has shown varying success in clinical trials. Understanding PC radioresistance and discovery of methods to sensitise PC to radiation will increase patient survival and improve quality of life. In this study, we identified PC radioresistance-associated pathways using global, unbiased techniques.

METHODS: Radioresistant cells were generated by sequential irradiation and recovery, and global genome cDNA microarray analysis was performed to identify differentially expressed genes in radiosensitive and radioresistant cells. Ingenuity pathway analysis was performed to discover cellular pathways …

Coprinus Comatus Cap Inhibits Adipocyte Differentiation Via Regulation Of Pparγ And Akt Signaling Pathway, Hyoung Joon Park, Jisoo Yun, Hong-Duck Kim, Chung-Kil Won, Gon-Sup Kim, Jae-Hyeon Cho

NYMC Faculty Publications

This study assessed the effects of Coprinus comatus cap (CCC) on adipogenesis in 3T3-L1 adipocytes and the effects of CCC on the development of diet-induced obesity in rats. Here, we showed that the CCC has an inhibitory effect on the adipocyte differentiation of 3T3-L1 cells, resulting in a significant decrease in lipid accumulation through the downregulation of several adipocyte specific-transcription factors, including CCAAT/enhancer binding protein β, C/EBPδ, and peroxisome proliferator-activated receptor gamma (PPARγ). Moreover, treatment with CCC during adipocyte differentiation induced a significant down-regulation of PPARγ and adipogenic target genes, including adipocyte protein 2, lipoprotein lipase, and adiponectin. Interestingly, the …

Enhancing Immunomodulation On Innate Immunity By Shape Transition Among Rna Triangle, Square And Pentagon Nanovehicles, Emil F. Khisamutdinov, Hui Li, Daniel L. Jasinski, Jiao Chen, Jian Fu, Peixuan Guo

Center for Research on Environmental Disease Faculty Publications

Modulation of immune response is important in cancer immunotherapy, vaccine adjuvant development and inflammatory or immune disease therapy. Here we report the development of new immunomodulators via control of shape transition among RNA triangle, square and pentagon. Changing one RNA strand in polygons automatically induced the stretching of the interior angle from 60° to 90° or 108°, resulting in self-assembly of elegant RNA triangles, squares and pentagons. When immunological adjuvants were incorporated, their immunomodulation effect for cytokine TNF-α and IL-6 induction was greatly enhanced in vitro and in animals up to 100-fold, while RNA polygon controls induced unnoticeable effect. The …

Nack Is An Integral Component Of The Notch Transcriptional Activation Complex And Is Critical For Development And Tumorigenesis, Kelly L Weaver, Marie-Clotilde Alves-Guerra, Ke Jin, Zhiqiang Wang, Xiaoqing Han, Prathibha Ranganathan, Xiaoxia Zhu, Thiago Dasilva, Wei Liu, Francesca Ratti, Renee M Demarest, Cristos Tzimas, Meghan Rice, Rodrigo Vasquez-Del Carpio, Nadia Dahmane, David J Robbins, Anthony J Capobianco

Rowan-Virtua School of Osteopathic Medicine Departmental Research

The Notch signaling pathway governs many distinct cellular processes by regulating transcriptional programs. The transcriptional response initiated by Notch is highly cell context dependent, indicating that multiple factors influence Notch target gene selection and activity. However, the mechanism by which Notch drives target gene transcription is not well understood. Herein, we identify and characterize a novel Notch-interacting protein, Notch activation complex kinase (NACK), which acts as a Notch transcriptional coactivator. We show that NACK associates with the Notch transcriptional activation complex on DNA, mediates Notch transcriptional activity, and is required for Notch-mediated tumorigenesis. We demonstrate that Notch1 and NACK are …

Olanzapine-Induced Methylation Alters Cadherin Gene Families And Associated Pathways Implicated In Psychosis, Melkaye G. Melka, Christina A Castellani, Nagalingam Rajakumar, Richard O'Reilly, Shiva M Singh

Biology Publications

BACKGROUND: The complex aetiology of most mental disorders involves gene-environment interactions that may operate using epigenetic mechanisms particularly DNA methylation. It may explain many of the features seen in mental disorders including transmission, expression and antipsychotic treatment responses. This report deals with the assessment of DNA methylation in response to an antipsychotic drug (olanzapine) on brain (cerebellum and hippocampus), and liver as a non-neural reference in a rat model. The study focuses on the Cadherin/protocadherins encoded by a multi-gene family that serve as adhesion molecules and are involved in cell-cell communication in the mammalian brain. A number of these molecules …

Sharp Emergence Of Feature-Selective Sustained Activity Along The Dorsal Visual Pathway., Diego Mendoza-Halliday, Santiago Torres, Julio C Martinez-Trujillo

Brain and Mind Institute Researchers' Publications

Sustained activity encoding visual working memory representations has been observed in several cortical areas of primates. Where along the visual pathways this activity emerges remains unknown. Here we show in macaques that sustained spiking activity encoding memorized visual motion directions is absent in direction-selective neurons in early visual area middle temporal (MT). However, it is robustly present immediately downstream, in multimodal association area medial superior temporal (MST), as well as and in the lateral prefrontal cortex (LPFC). This sharp emergence of sustained activity along the dorsal visual pathway suggests a functional boundary between early visual areas, which encode sensory inputs, …

Cytokine Gene Expression Profiles During Initiation, Progression And Resolution Of Periodontitis, Jeffrey L. Ebersole, Sreenatha S. Kirakodu, Michael John Novak, Arnold J. Stromberg, Shu Shen, Luis Orraca, Janis Gonzalez-Martinez, Armando Burgos, Octavio A. Gonzalez

Center for Oral Health Research Faculty Publications

AIM: Variations in the expression of cytokines during the progression of periodontitis remain ill-defined. We evaluated the expression of 19 cytokine genes related to T-cell phenotype/function during initiation, progression and resolution of periodontitis, and related these to the expression of soft and bone tissue destruction genes (TDGs).

MATERIALS AND METHODS: A ligature-induced periodontitis model was used in rhesus monkeys (M. mulatta) (n = 18). Gingival tissues were taken at baseline pre-ligation, 2 weeks and 1 month (Initiation) and 3 months (progression) post ligation. Ligatures were removed and samples taken 2 months later (resolution). Total RNA was isolated and the Rhesus …

Impact Of Distinct Poxvirus Infections On The Specificities And Functionalities Of Cd4+ T Cell Responses., Nicholas A Siciliano, Adam R Hersperger, Aimee M Lacuanan, Ren-Huan Xu, John Sidney, Alessandro Sette, Luis J Sigal, Laurence C. Eisenlohr

Department of Microbiology and Immunology Faculty Papers

UNLABELLED: The factors that determine CD4+ T cell (TCD4+) specificities, functional capacity, and memory persistence in response to complex pathogens remain unclear. We explored these parameters in the C57BL/6 mouse through comparison of two highly related (>92% homology) poxviruses: ectromelia virus (ECTV), a natural mouse pathogen, and vaccinia virus (VACV), a heterologous virus that nevertheless elicits potent immune responses. In addition to elucidating several previously unidentified major histocompatibility complex class II (MHC-II)-restricted epitopes, we observed many qualitative and quantitative differences between the TCD4+ repertoires, including responses not elicited by VACV despite complete sequence conservation. In addition, we observed functional …

Safety Of Topiramate For Treating Migraines., Michael J. Marmura

Department of Jefferson Headache Center Papers and Presentations

INTRODUCTION: Migraine is a very common medical disorder characterized by attacks of moderate-severe headache, nausea and disability. Topiramate is an effective, popular prophylactic migraine treatment, which is approved for use in adults and adolescents. Due to its multiple mechanisms of action, topiramate has multiple potential safety issues, including systemic and CNS adverse events, which may complicate therapy.

AREAS COVERED: This review evaluates common adverse events as seen in the pivotal trials of topiramate for migraine as well as those observed in postmarketing studies. These include weight loss, metabolic acidosis, renal calculi, acute angle closure glaucoma, visual distortions and cognitive slowing. …

Vaccination With A Genetically Modified Brugia Malayi Cysteine Protease Inhibitor-2 Reduces Adult Parasite Numbers And Affects The Fertility Of Female Worms Following A Subcutaneous Challenge Of Mongolian Gerbils (Meriones Unguiculatus) With B. Malayi Infective Larvae., Sridhar Arumugam, Junfei Wei, Danielle Ward, David Abraham, Sara Lustigman, Bin Zhan, Thomas R. Klei

Department of Microbiology and Immunology Faculty Papers

Vaccination of Mongolian gerbils with Brugia malayi cysteine protease inhibitor-2 in which the amino acid Asn66 was mutated to Lys66 (Bm-CPI-2M) resulted in reduced parasite numbers of 48.6% and 48.0% at 42 and 90 days p.i. with B. malayi L3s. Fertility of female worms was also affected at 90 days p.i. In vitro killing of L3s observed in the presence of gerbil peritoneal exudate cells and anti-Bm-CPI-2M sera suggests antibody-dependent cell-mediated cytotoxicity as a putative protective mechanism. These observations suggest that Bm-CPI-2M is a promising prophylactic and anti-fecundity vaccine candidate.

Clones Of Streptococcus Zooepidemicus From Outbreaks Of Hemorrhagic Canine Pneumonia And Associated Immune Responses, Sridhar Velineni, John F. Timoney, Kim Russell, Heidi J. Hamlen, Patricia Pesavento, William D. Fortney, P. Cynda Crawford

Maxwell H. Gluck Equine Research Center Faculty Publications

Acute hemorrhagic pneumonia caused by Streptococcus zooepidemicus has emerged as a major disease of shelter dogs and greyhounds. S. zooepidemicus strains differing in multilocus sequence typing (MLST), protective protein (SzP), and M-like protein (SzM) sequences were identified from 9 outbreaks in Texas, Kansas, Florida, Nevada, New Mexico, and Pennsylvania. Clonality based on 2 or more isolates was evident for 7 of these outbreaks. The Pennsylvania and Nevada outbreaks also involved cats. Goat antisera against acutely infected lung tissue as well as convalescent-phase sera reacted with a mucinase (Sz115), hyaluronidase (HylC), InlA domain-containing cell surface-anchored protein (INLA), membrane-anchored protein (MAP), SzP, …

Fructose-2,6-Bisphosphate Synthesis By 6-Phosphofructo-2-Kinase/Fructose-2,6-Bisphosphatase 4 (Pfkfb4) Is Required For The Glycolytic Response To Hypoxia And Tumor Growth, Jason Chesney, Jennifer Clark, Alden C. Klarer, Yoannis Imbert-Fernandez, Andrew N. Lane, Sucheta Telang

Markey Cancer Center Faculty Publications

Fructose-2,6-bisphosphate (F2,6BP) is a shunt product of glycolysis that allosterically activates 6-phosphofructo-1-kinase (PFK-1) resulting in increased glucose uptake and glycolytic flux to lactate. The F2,6BP concentration is dictated by four bifunctional 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatases (PFKFB1-4) with distinct kinase:phosphatase activities. PFKFB4 is over-expressed in human cancers, induced by hypoxia and required for survival and growth of several cancer cell lines. Although PFKFB4 appears to be a rational target for anti-neoplastic drug development, it is not clear whether its kinase or phosphatase activity is required for cancer cell survival. In this study, we demonstrate that recombinant human PFKFB4 kinase activity is 4.3-fold greater than …

Applying Accelerator Mass Spectrometry For Low-Level Detection Of Complex Engineered Nanoparticles In Biological Media, Binghui Wang, George S. Jackson, Robert A. Yokel, Eric A. Grulke

Pharmaceutical Sciences Faculty Publications

Complex engineered nanoparticles (CENPs), which have different core and surface components, are being developed for medicinal, pharmaceutical and industrial applications. One of the key challenges for environmental health and safety assessments of CENPs is to identify and quantity their transformations in biological environments. This study reports the effects of in vivo exposure of citrate-coated nanoalumina with different rare isotope labels on each component. This CENP was dosed to the rat and accelerator mass spectrometry (AMS) was used to quantify ²⁶Al, ¹⁴C, and their ratio in the dosing material and tissue samples. For CENPs detected in the liver, the …

Nuclear Glycolytic Enzyme Enolase Of Toxoplasma Gondii Functions As A Transcriptional Regulator, Thomas Mouveaux, Gabrielle Oria, Elisabeth Werkmeister, Christian Slomianny, Barbara A. Fox, David J. Bzik, Stanislas Tomavo

Dartmouth Scholarship

Apicomplexan parasites including Toxoplasma gondii have complex life cycles within different hosts and their infectivity relies on their capacity to regulate gene expression. However, little is known about the nuclear factors that regulate gene expression in these pathogens. Here, we report that T. gondii enolase TgENO2 is targeted to the nucleus of actively replicating parasites, where it specifically binds to nuclear chromatin in vivo. Using a ChIP-Seq technique, we provide evidence for TgENO2 enrichment at the 5′ untranslated gene regions containing the putative promoters of 241 nuclear genes. Ectopic expression of HA-tagged TgENO1 or TgENO2 led to changes in …

Neuroinflammation And Neurologic Deficits In Diabetes Linked To Brain Accumulation Of Amylin, Sarah Srodulski, Savita Sharma, Adam B. Bachstetter, Jennifer M. Brelsfoard, Conrado Pascual, Xinmin Simon Xie, Kathryn E. Saatman, Linda J. Van Eldik, Florin Despa

Pharmacology and Nutritional Sciences Faculty Publications

BACKGROUND: We recently found that brain tissue from patients with type-2 diabetes (T2D) and cognitive impairment contains deposits of amylin, an amyloidogenic hormone synthesized and co-secreted with insulin by pancreatic β-cells. Amylin deposition is promoted by chronic hypersecretion of amylin (hyperamylinemia), which is common in humans with obesity or pre-diabetic insulin resistance. Human amylin oligomerizes quickly when oversecreted, which is toxic, induces inflammation in pancreatic islets and contributes to the development of T2D. Here, we tested the hypothesis that accumulation of oligomerized amylin affects brain function.

METHODS: In contrast to amylin from humans, rodent amylin is neither amyloidogenic nor cytotoxic. …

Relating Gene Expression Evolution With Cpg Content Changes, Huan Yang, Dawei Li, Chao Cheng

Dartmouth Scholarship

Background:

Previous studies have shown that CpG dinucleotides are enriched in a subset of promoters and the CpG content of promoters is positively correlated with gene expression levels. But the relationship between divergence of CpG content and gene expression evolution has not been investigated. Here we calculate the normalized CpG (nCpG) content in DNA regions around transcription start site (TSS) and transcription terminal site (TTS) of genes in nine organisms, and relate them with expression levels measured by RNA-seq.

Results:

The nCpG content of TSS shows a bimodal distribution in all organisms except platypus, whereas the nCpG content of TTS …

Adrenergic Signaling Regulates Mitochondrial Ca2+ Uptake Through Pyk2-Dependent Tyrosine Phosphorylation Of The Mitochondrial Ca2+ Uniporter., Jin O-Uchi, Bong Sook Jhun, Shangcheng Xu, Stephen Hurst, Anna Raffaello, Xiaoyun Liu, Bing Yi, Huiliang Zhang, Polina Gross, Jyotsna Mishra, Alina Ainbinder, Sarah Kettlewell, Godfrey L Smith, Robert T Dirksen, Wang Wang, Rosario Rizzuto, Shey-Shing Sheu

Department of Medicine Faculty Papers

AIMS: Mitochondrial Ca2+ homeostasis is crucial for balancing cell survival and death. The recent discovery of the molecular identity of the mitochondrial Ca2+ uniporter pore (MCU) opens new possibilities for applying genetic approaches to study mitochondrial Ca2+ regulation in various cell types, including cardiac myocytes. Basal tyrosine phosphorylation of MCU was reported from mass spectroscopy of human and mouse tissues, but the signaling pathways that regulate mitochondrial Ca2+ entry through posttranslational modifications of MCU are completely unknown. Therefore, we investigated α1-adrenergic-mediated signal transduction of MCU posttranslational modification and function in cardiac cells.

RESULTS: α1-adrenoceptor (α1-AR) signaling translocated activated proline-rich tyrosine …

Mitochondrial Ion Channels/Transporters As Sensors And Regulators Of Cellular Redox Signaling., Jin O-Uchi, Shin-Young Ryu, Bong Sook Jhun, Stephen Hurst, Shey-Shing Sheu

Department of Medicine Faculty Papers

SIGNIFICANCE: Mitochondrial ion channels/transporters and the electron transport chain (ETC) serve as key sensors and regulators for cellular redox signaling, the production of reactive oxygen species (ROS) and nitrogen species (RNS) in mitochondria, and balancing cell survival and death. Although the functional and pharmacological characteristics of mitochondrial ion transport mechanisms have been extensively studied for several decades, the majority of the molecular identities that are responsible for these channels/transporters have remained a mystery until very recently.

RECENT ADVANCES: Recent breakthrough studies uncovered the molecular identities of the diverse array of major mitochondrial ion channels/transporters, including the mitochondrial Ca2+ uniporter pore, …