Medicine and Health Sciences Commons^™

Proteomic Alterations Of Hdl In Youth With Type 1 Diabetes And Their Associations With Glycemic Control: A Case-Control Study, Evgenia Gourgari, Junfeng Ma, Martin P. Playford, Nehal N. Mehta, Radoslav Goldman, Alan T. Remaley, Scott M. Gordon

Saha Cardiovascular Research Center Faculty Publications

Background: Patients with type 1 diabetes (T1DM) typically have normal or even elevated plasma high density lipoprotein (HDL) cholesterol concentrations; however, HDL protein composition can be altered without a change in cholesterol content. Alteration of the HDL proteome can result in dysfunctional HDL particles with reduced ability to protect against cardiovascular disease (CVD). The objective of this study was to compare the HDL proteomes of youth with T1DM and healthy controls (HC) and to evaluate the influence of glycemic control on HDL protein composition.

Methods: This was a cross-sectional case–control study. Blood samples were obtained from patients with T1DM and …

Collagen Prolyl 4-Hydroxylase 1 Is Essential For Hif-1Α Stabilization And Tnbc Chemoresistance, Gaofeng Xiong, Rachel L. Stewart, Jie Chen, Tianyan Gao, Timothy L. Scott, Luis M. Samayoa, Kathleen L. O'Connor, Andrew N. Lane, Ren Xu

Markey Cancer Center Faculty Publications

Collagen prolyl 4-hydroxylase (P4H) expression and collagen hydroxylation in cancer cells are necessary for breast cancer progression. Here, we show that P4H alpha 1 subunit (P4HA1) protein expression is induced in triple-negative breast cancer (TNBC) and HER2 positive breast cancer. By modulating alpha ketoglutarate (α-KG) and succinate levels P4HA1 expression reduces proline hydroxylation on hypoxia-inducible factor (HIF) 1α, enhancing its stability in cancer cells. Activation of the P4HA/HIF-1 axis enhances cancer cell stemness, accompanied by decreased oxidative phosphorylation and reactive oxygen species (ROS) levels. Inhibition of P4HA1 sensitizes TNBC to the chemotherapeutic agent docetaxel and doxorubicin in xenografts and patient-derived …

Differential Effects Of Linkers On The Activity Of Amphiphilic Tobramycin Antifungals, Marina Y. Fosso, Sanjib K. Shrestha, Nishad Thamban Chandrika, Emily K. Dennis, Keith D. Green, Sylvie Garneau-Tsodikova

Pharmaceutical Sciences Faculty Publications

As the threat associated with fungal infections continues to rise and the availability of antifungal drugs remains a concern, it becomes obvious that the need to bolster the antifungal armamentarium is urgent. Building from our previous findings of tobramycin (TOB) derivatives with antifungal activity, we further investigate the effects of various linkers on the biological activity of these aminoglycosides. Herein, we analyze how thioether, sulfone, triazole, amide, and ether functionalities affect the antifungal activity of alkylated TOB derivatives against 22 Candida, Cryptococcus, and Aspergillus species. We also evaluate their impact on the hemolysis of murine erythrocytes and the …

Novel Fluconazole Derivatives With Promising Antifungal Activity, Nishad Thamban Chandrika, Sanjib K. Shrestha, Huy X. Ngo, Kaitlind C. Howard, Sylvie Garneau-Tsodikova

Pharmaceutical Sciences Faculty Publications

The fungistatic nature and toxicity concern associated with the azole drugs currently on the market have resulted in an increased demand for new azole antifungal agents for which these problematic characteristics do not exist. The extensive use of azoles has resulted in fungal strains capable of resisting the action of these drugs. Herein, we report the synthesis and antifungal activities of novel fluconazole (FLC) analogues with alkyl-, aryl-, cycloalkyl-, and dialkyl-amino substituents. We evaluated their antifungal activity by MIC determination and time-kill assay as well as their safety profile by hemolytic activity against murine erythrocytes as well as cytotoxicity against …

Beta-Catenin Cleavage Enhances Transcriptional Activation, Tatiana Goretsky, Emily M. Bradford, Qing Ye, Olivia F. Lamping, Tomas Vanagunas, Mary Pat Moyer, Patrick C. Keller, Preetika Sinh, Josep M. Llovet, Tianyan Gao, Qing-Bai She, Linheng Li, Terrence A. Barrett

Internal Medicine Faculty Publications

Nuclear activation of Wnt/β-catenin signaling is required for cell proliferation in inflammation and cancer. Studies from our group indicate that β-catenin activation in colitis and colorectal cancer (CRC) correlates with increased nuclear levels of β-catenin phosphorylated at serine 552 (pβ-Cat⁵⁵²). Biochemical analysis of nuclear extracts from cancer biopsies revealed the existence of low molecular weight (LMW) pβ-Cat⁵⁵², increased to the exclusion of full size (FS) forms of β-catenin. LMW β-catenin lacks both termini, leaving residues in the armadillo repeat intact. Further experiments showed that TCF4 predominantly binds LMW pβ-Cat⁵⁵² in the nucleus of inflamed and …

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 …

Mutsβ Abundance And Msh3 Atp Hydrolysis Activity Are Important Drivers Of Ctg•Cag Repeat Expansions, Norma Keogh, Kara Y. Chan, Guo-Min Li, Robert S. Lahue

Toxicology and Cancer Biology Faculty Publications

CTG•CAG repeat expansions cause at least twelve inherited neurological diseases. Expansions require the presence, not the absence, of the mismatch repair protein MutSβ (Msh2-Msh3 heterodimer). To evaluate properties of MutSβ that drive expansions, previous studies have tested under-expression, ATPase function or polymorphic variants of Msh2 and Msh3, but in disparate experimental systems. Additionally, some variants destabilize MutSβ, potentially masking the effects of biochemical alterations of the variations. Here, human Msh3 was mutated to selectively inactivate MutSβ. Msh3^−/− cells are severely defective for CTG•CAG repeat expansions but show full activity on contractions. Msh3^−/− cells provide a single, isogenic system …

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 …

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 …

Retention Of Normal Glia Function By An Isoform-Selective Protein Kinase Inhibitor Drug Candidate That Modulates Cytokine Production And Cognitive Outcomes, Zhengqiu Zhou, Adam D. Bachstetter, Claudia B. Späni, Saktimayee M. Roy, D. Martin Watterson, Linda J. Van Eldik

Sanders-Brown Center on Aging Faculty Publications

Background: Brain p38α mitogen-activated protein kinase (MAPK), a potential therapeutic target for cognitive dysfunction based on the neuroinflammation-synaptic dysfunction cycle of pathophysiology progression, offers an innovative pharmacological strategy via inhibiting the same activated target in both glia and neurons, thereby enhancing the possibility for efficacy. The highly selective, brain-penetrant p38αMAPK inhibitor MW150 attenuates cognitive dysfunction in two distinct Alzheimer's disease (AD)-relevant models and avoids the problems encountered with previous mixed-kinase inhibitor drug candidates. Therefore, it is essential that the glial effects of this CNS-active kinase inhibitor be addressed in order to anticipate future use in clinical investigations.

Methods: …

Increased Ros Production In Non-Polarized Mammary Epithelial Cells Induces Monocyte Infiltration In 3d Culture, Linzhang Li, Jie Chen, Gaofeng Xiong, Daret K. St. Clair, Wei Xu, Ren Xu

Markey Cancer Center Faculty Publications

Loss of epithelial cell polarity promotes cell invasion and cancer dissemination. Therefore, identification of factors that disrupt polarized acinar formation is crucial. Reactive oxygen species (ROS) drive cancer progression and promote inflammation. Here, we show that the non-polarized breast cancer cell line T4-2 generates significantly higher ROS levels than polarized S1 and T4R cells in three-dimensional (3D) culture, accompanied by induction of the nuclear factor κB (NF-κB) pathway and cytokine expression. Minimizing ROS in T4-2 cells with antioxidants reestablished basal polarity and inhibited cell proliferation. Introducing constitutively activated RAC1 disrupted cell polarity and increased ROS levels, indicating that RAC1 is …

Bis(N-Amidinohydrazones) And N-(Amidino)-N'-Aryl-Bishydrazones: New Classes Of Antibacterial/Antifungal Agents, Sanjib K. Shrestha, Liliia M. Kril, Keith D. Green, Stefan Kwiatkowski, Vitaliy M. Sviripa, Justin Robert Nickell, Linda Phyliss Dwoskin, David S. Watt, Sylvie Garneau-Tsodikova

Pharmaceutical Sciences Faculty Publications

The emergence of multidrug-resistant bacterial and fungal strains poses a threat to human health that requires the design and synthesis of new classes of antimicr obial agents. We evaluated bis(N-amidinohydrazones) and N-(amidino)-N'-aryl-bishydrazones for their antibacterial and antifungal activities against panels of Gram-positive/Gram-negative bacteria as well as fungi. We investigated their potential to develop resistance against both bacteria and fungi by a multi-step, resistance-selection method, explored their potential to induce the production of reactive oxygen species, and assessed their toxicity. In summary, we found that these compounds exhibited broad-spectrum antibacterial and antifungal activities against most of …

Exposure Of Human Lung Cells To Tobacco Smoke Condensate Inhibits The Nucleotide Excision Repair Pathway, Nathaniel C. Holcomb, Mamta Goswami, Sung Gu Han, Samuel Clark, David K. Orren, C. Gary Gairola, Isabel Mellon

Toxicology and Cancer Biology Faculty Publications

Exposure to tobacco smoke is the number one risk factor for lung cancer. Although the DNA damaging properties of tobacco smoke have been well documented, relatively few studies have examined its effect on DNA repair pathways. This is especially true for the nucleotide excision repair (NER) pathway which recognizes and removes many structurally diverse DNA lesions, including those introduced by chemical carcinogens present in tobacco smoke. The aim of the present study was to investigate the effect of tobacco smoke on NER in human lung cells. We studied the effect of cigarette smoke condensate (CSC), a surrogate for tobacco smoke, …

Thrombospondin 1 Deficiency Ameliorates The Development Of Adriamycin-Induced Proteinuric Kidney Disease, Hasiyeti Maimaitiyiming, Qi Zhou, Shuxia Wang

Pharmacology and Nutritional Sciences Faculty Publications

Accumulating evidence suggests that thrombospondin 1 (TSP1) is an important player in diabetic nephropathy. However, the role of TSP1 in podocyte injury and the development of non-diabetic proteinuric kidney disease is largely unknown. In the current study, by using a well-established podocyte injury model (adriamycin-induced nephropathy mouse model), we examined the contribution of TSP1 to the development of proteinuric kidney disease. We found that TSP1 was up-regulated in the glomeruli, notably in podocytes, in adriamycin injected mice before the onset of proteinuria. ADR treatment also stimulated TSP1 expression in cultured human podocytes in vitro. Moreover, increased TSP1 mediated ADR-induced …

Quantitative Mass Spectrometry Reveals Changes In Histone H2b Variants As Cells Undergo Inorganic Arsenic-Mediated Cellular Transformation, Matthew Rea, Tingting Jiang, Rebekah Eleazer, Meredith Eckstein, Alan G. Marshall, Yvonne N. Fondufe-Mittendorf

Molecular and Cellular Biochemistry Faculty Publications

Exposure to inorganic arsenic, a ubiquitous environmental toxic metalloid, leads to carcinogenesis. However, the mechanism is unknown. Several studies have shown that inorganic arsenic exposure alters specific gene expression patterns, possibly through alterations in chromatin structure. While most studies on understanding the mechanism of chromatin-mediated gene regulation have focused on histone post-translational modifications, the role of histone variants remains largely unknown. Incorporation of histone variants alters the functional properties of chromatin. To understand the global dynamics of chromatin structure and function in arsenic-mediated carcinogenesis, analysis of the histone variants incorporated into the nucleosome and their covalent modifications is required. Here …

Equine Arteritis Virus Uses Equine Cxcl16 As An Entry Receptor, Sanjay Sarkar, Lakshman Chelvarajan, Yun Young Go, Frank Cook, Sergey Artiushin, Shankar Mondal, Kelsi Anderson, John E. Eberth, Peter J. Timoney, Theodore S. Kalbfleisch, Ernest F. Bailey, Udeni B. R. Balasuriya

Veterinary Science Faculty Publications

Previous studies in our laboratory have identified equine CXCL16 (EqCXCL16) to be a candidate molecule and possible cell entry receptor for equine arteritis virus (EAV). In horses, the CXCL16 gene is located on equine chromosome 11 (ECA11) and encodes a glycosylated, type I transmembrane protein with 247 amino acids. Stable transfection of HEK-293T cells with plasmid DNA carrying EqCXCL16 (HEK-EqCXCL16 cells) increased the proportion of the cell population permissive to EAV infection from < 3% to almost 100%. The increase in permissiveness was blocked either by transfection of HEK-EqCXCL16 cells with small interfering RNAs (siRNAs) directed against EqCXCL16 or by pretreatment with guinea pig polyclonal antibody against EqCXCL16 protein (Gp anti-EqCXCL16 pAb). Furthermore, using a virus overlay protein-binding assay (VOPBA) in combination with far-Western blotting, gradient-purified EAV particles were shown to bind directly to the EqCXCL16 protein in vitro. The binding of biotinylated virulent EAV strain Bucyrus at 4°C was significantly higher in HEK-EqCXCL16 cells than nontransfected HEK-293T cells. Finally, the results demonstrated …

Mw151 Inhibited Il-1Β Levels After Traumatic Brain Injury With No Effect On Microglia Physiological Responses, Adam D. Bachstetter, Zhengqiu Zhou, Rachel K. Rowe, Bin Xing, Danielle S. Goulding, Alyssa N. Conley, Pradoldej Sompol, Shelby Meier, Jose F. Abisambra, Jonathan Lifshitz, D. Martin Watterson, Linda J. Van Eldik

Sanders-Brown Center on Aging Faculty Publications

A prevailing neuroinflammation hypothesis is that increased production of proinflammatory cytokines contributes to progressive neuropathology, secondary to the primary damage caused by a traumatic brain injury (TBI). In support of the hypothesis, post-injury interventions that inhibit the proinflammatory cytokine surge can attenuate the progressive pathology. However, other post-injury neuroinflammatory responses are key to endogenous recovery responses. Therefore, it is critical that pharmacological attenuation of detrimental or dysregulated neuroinflammatory processes avoid pan-suppression of inflammation. MW151 is a CNS-penetrant, small molecule experimental therapeutic that restores injury- or disease-induced overproduction of proinflammatory cytokines towards homeostasis without immunosuppression. Post-injury administration of MW151 in a …

Gap Junction Mediated Mirna Intercellular Transfer And Gene Regulation: A Novel Mechanism For Intercellular Genetic Communication, Liang Zong, Yan Zhu, Ruqiang Liang, Hong-Bo Zhao

Otolaryngology--Head & Neck Surgery Faculty Publications

Intercellular genetic communication is an essential requirement for coordination of cell proliferation and differentiation and has an important role in many cellular processes. Gap junction channels possess large pore allowing passage of ions and small molecules between cells. MicroRNAs (miRNAs) are small regulatory RNAs that can regulate gene expression broadly. Here, we report that miRNAs can pass through gap junction channels in a connexin-dependent manner. Connexin43 (Cx43) had higher permeability, whereas Cx30 showed little permeability to miRNAs. In the tested connexin cell lines, the permeability to miRNAs demonstrated: Cx43 > Cx26/30 > Cx26 > Cx31 > Cx30 = Cx-null. However, consistent with a uniform …

Coordination Of Rna Polymerase Ii Pausing And 3' End Processing Factor Recruitment With Alternative Polyadenylation, Becky Fusby, Soojin Kim, Benjamin Erickson, Hyunmin Kim, Martha L. Peterson, David L Bentley

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Most mammalian genes produce transcripts whose 3' ends are processed at multiple alternative positions by cleavage/polyadenylation (CPA). Poly(A) site cleavage frequently occurs cotranscriptionally and is facilitated by CPA factor binding to the RNA polymerase II (Pol II) C-terminal domain (CTD) phosphorylated on Ser2 residues of its heptad repeats (YS₂PTSPS). The function of cotranscriptional events in the selection of alternative poly(A) sites is poorly understood. We investigated Pol II pausing, CTD Ser2 phosphorylation, and processing factor CstF recruitment at wild-type and mutant IgM transgenes that use alternative poly(A) sites to produce mRNAs encoding the secreted and membrane-bound forms of …

Integrin Α6Β4 Promotes Autocrine Epidermal Growth Factor Receptor (Egfr) Signaling To Stimulate Migration And Invasion Toward Hepatocyte Growth Factor (Hgf), Brittany L. Carpenter, Min Chen, Teresa Knifley, Kelley A. Davis, Susan M.W. Harrison, Rachel L. Stewart, Kathleen O'Connor

Markey Cancer Center Faculty Publications

Integrin α6β4 is up-regulated in pancreatic adenocarcinomas where it contributes to carcinoma cell invasion by altering the transcriptome. In this study, we found that integrin α6β4 up-regulates several genes in the epidermal growth factor receptor (EGFR) pathway, including amphiregulin (AREG), epiregulin (EREG), and ectodomain cleavage protease MMP1, which is mediated by promoter demethylation and NFAT5. The correlation of these genes with integrin α6β4 was confirmed in The Cancer Genome Atlas Pancreatic Cancer Database. Based on previous observations that integrin α6β4 cooperates with c-Met in pancreatic cancers, we examined the impact of EGFR signaling on hepatocyte growth factor (HGF)-stimulated migration and …

Antioncogenic And Oncogenic Properties Of Nrf2 In Arsenic-Induced Carcinogenesis, Young-Ok Son, Poyil Pratheeshkumar, Ram Vinod Roy, Andrew Hitron, Lei Wang, Sasidharan Padmaja Divya, Mei Xu, Jia Luo, Gang Chen, Zhuo Zhang, Xianglin Shi

Center for Research on Environmental Disease Faculty Publications

Arsenic (As³⁺) is a carcinogen with considerable environmental and occupational relevancy. The present study shows that As³⁺-transformed human lung bronchial epithelial BEAS-2B cells (AsT cells) exhibit the property of apoptosis resistance. The level of basal reactive oxygen species (ROS) is very low in AsT cells in correlation with elevated expressions of both antioxidant enzymes and antiapoptotic proteins. Nuclear factor erythroid 2-related factor (Nrf2) and p62 are constitutively expressed. These two proteins up-regulate antioxidant enzymes and antiapoptotic proteins. The knockdown of Nrf2 or p62 by small interfering RNA (siRNA) enhanced both ROS levels and As³⁺-induced …

Cd151-Α3Β1 Integrin Complexes Are Prognostic Markers Of Glioblastoma And Cooperate With Egfr To Drive Tumor Cell Motility And Invasion, Pengcheng Zhou, Sonia Erfani, Zeyi Liu, Changhe Jia, Yecang Chen, Bingwei Xu, Xinyu Deng, Jose E. Alfáro, Li Chen, Dana L. Napier, Michael Lu, Jian-An Huang, Chunming Liu, Olivier Thibault, Rosalind Segal, Binhua P. Zhou, Natasha Kyprianou, Craig Horbinski, Xiuwei H. Yang

Pharmacology and Nutritional Sciences Faculty Publications

Glioblastoma, one of the most aggressive forms of brain cancer, is featured by high tumor cell motility and invasiveness, which not only fuel tumor infiltration, but also enable escape from surgical or other clinical interventions. Thus, better understanding of how these malignant traits are controlled will be key to the discovery of novel biomarkers and therapies against this deadly disease. Tetraspanin CD151 and its associated α3β1 integrin have been implicated in facilitating tumor progression across multiple cancer types. How these adhesion molecules are involved in the progression of glioblastoma, however, remains largely unclear. Here, we examined an in-house tissue microarray-based …

Increased Expression Of Fatty Acid Synthase Provides A Survival Advantage To Colorectal Cancer Cells Via Upregulation Of Cellular Respiration, Yekaterina Y. Zaytseva, Jennifer W. Harris, Mihail I. Mitov, Ji Tae Kim, D. Allan Butterfield, Eun Young Lee, Heidi L. Weiss, Tianyan Gao, B. Mark Evers

Markey Cancer Center Faculty Publications

Fatty acid synthase (FASN), a lipogenic enzyme, is upregulated in colorectal cancer (CRC). Increased de novo lipid synthesis is thought to be a metabolic adaptation of cancer cells that promotes survival and metastasis; however, the mechanisms for this phenomenon are not fully understood. We show that FASN plays a role in regulation of energy homeostasis by enhancing cellular respiration in CRC. We demonstrate that endogenously synthesized lipids fuel fatty acid oxidation, particularly during metabolic stress, and maintain energy homeostasis. Increased FASN expression is associated with a decrease in activation of energy-sensing pathways and accumulation of lipid droplets in CRC cells …

Truncating Mutation In The Autophagy Gene Uvrag Confers Oncogenic Properties And Chemosensitivity In Colorectal Cancers, Shanshan He, Zhen Zhao, Yongfei Yang, Douglas O'Connell, Xiaowei Zhang, Soohwan Oh, Binyun Ma, Joo-Hyung Lee, Tian Zhang, Bino Varghese, Janae Yip, Sara Dolatshahi Pirooz, Ming Li, Yong Zhang, Guo-Min Li, Sue Ellen Martin, Keigo Machida, Chengyu Liang

Toxicology and Cancer Biology Faculty Publications

Autophagy-related factors are implicated in metabolic adaptation and cancer metastasis. However, the role of autophagy factors in cancer progression and their effect in treatment response remain largely elusive. Recent studies have shown that UVRAG, a key autophagic tumour suppressor, is mutated in common human cancers. Here we demonstrate that the cancer-related UVRAG frameshift (FS), which does not result in a null mutation, is expressed as a truncated UVRAG^FS in colorectal cancer (CRC) with microsatellite instability (MSI), and promotes tumorigenesis. UVRAG^FS abrogates the normal functions of UVRAG, including autophagy, in a dominant-negative manner. Furthermore, expression of UVRAG^FS can …

Amphiphilic Tobramycin Analogues As Antibacterial And Antifungal Agents, Sanjib K. Shrestha, Marina Y. Fosso, Keith D. Green, Sylvie Garneau-Tsodikova

Pharmaceutical Sciences Faculty Publications

In this study, we investigated the in vitro antifungal activities, cytotoxicities, and membrane-disruptive actions of amphiphilic tobramycin (TOB) analogues. The antifungal activities were established by determination of MIC values and in time-kill studies. Cytotoxicity was evaluated in mammalian cell lines. The fungal membrane-disruptive action of these analogues was studied by using the membrane-impermeable dye propidium iodide. TOB analogues bearing a linear alkyl chain at their 6″-position in a thioether linkage exhibited chain length-dependent antifungal activities. Analogues with C₁₂ and C₁₄ chains showed promising antifungal activities against tested fungal strains, with MIC values ranging from 1.95 to 62.5 mg/liter …

Targeted Dna Damage At Individual Telomeres Disrupts Their Integrity And Triggers Cell Death, Luxi Sun, Rong Tan, Jianquan Xu, Justin Laface, Ying Gao, Yanchun Xiao, Myriam Attar, Carola Neumann, Guo-Min Li, Bing Su, Yang Liu, Satoshi Nakajima, Arthur S. Levine, Li Lan

Markey Cancer Center Faculty Publications

Cellular DNA is organized into chromosomes and capped by a unique nucleoprotein structure, the telomere. Both oxidative stress and telomere shortening/dysfunction cause aging-related degenerative pathologies and increase cancer risk. However, a direct connection between oxidative damage to telomeric DNA, comprising <1% of the genome, and telomere dysfunction has not been established. By fusing the KillerRed chromophore with the telomere repeat binding factor 1, TRF1, we developed a novel approach to generate localized damage to telomere DNA and to monitor the real time damage response at the single telomere level. We found that DNA damage at long telomeres in U2OS cells is not repaired efficiently compared to DNA damage in non-telomeric regions of the same length in heterochromatin. Telomeric DNA damage shortens the average length of telomeres and leads to cell senescence in HeLa cells and cell death in HeLa, U2OS and IMR90 cells, when DNA damage at non-telomeric regions is undetectable. Telomere-specific damage induces chromosomal aberrations, including chromatid telomere loss and telomere associations, distinct from the damage induced by ionizing irradiation. Taken together, our results demonstrate that oxidative damage induces telomere dysfunction and underline the importance of maintaining telomere integrity upon oxidative damage.

Alternating Magnetic Field-Induced Hyperthermia Increases Iron Oxide Nanoparticle Cell Association/Uptake And Flux In Blood-Brain Barrier Models, Mo Dan, Younsoo Bae, Thomas A. Pittman, Robert A. Yokel

Pharmaceutical Sciences Faculty Publications

PURPOSE: Superparamagnetic iron oxide nanoparticles (IONPs) are being investigated for brain cancer therapy because alternating magnetic field (AMF) activates them to produce hyperthermia. For central nervous system applications, brain entry of diagnostic and therapeutic agents is usually essential. We hypothesized that AMF-induced hyperthermia significantly increases IONP blood-brain barrier (BBB) association/uptake and flux.

METHODS: Cross-linked nanoassemblies loaded with IONPs (CNA-IONPs) and conventional citrate-coated IONPs (citrate-IONPs) were synthesized and characterized in house. CNA-IONP and citrate-IONP BBB cell association/uptake and flux were studied using two BBB Transwell^® models (bEnd.3 and MDCKII cells) after conventional and AMF-induced hyperthermia exposure.

RESULTS: …

Chemoselective Detection And Discrimination Of Carbonyl-Containing Compounds In Metabolite Mixtures By 1H-Detected 15N Nuclear Magnetic Resonance, Andrew N. Lane, Sengodagounder Arumugam, Pawel Lorkiewicz, Richard M. Higashi, Sébastien Laulhé, Michael H. Nantz, Hunter N. B. Moseley, Teresa W-M Fan

Toxicology and Cancer Biology Faculty Publications

NMR spectra of mixtures of metabolites extracted from cells or tissues are extremely complex, reflecting the large number of compounds that are present over a wide range of concentrations. Although multidimensional NMR can greatly improve resolution as well as improve reliability of compound assignments, lower abundance metabolites often remain hidden. We have developed a carbonyl-selective aminooxy probe that specifically reacts with free keto and aldehyde functions, but not carboxylates. By incorporating ¹⁵N in the aminooxy functional group, ¹⁵N-edited NMR was used to select exclusively those metabolites that contain a free carbonyl function while all other metabolites are rejected. …

Targeting Human Central Nervous System Protein Kinases: An Isoform Selective P38Αmapk Inhibitor That Attenuates Disease Progression In Alzheimer's Disease Mouse Models, Saktimayee M. Roy, Valerie L. Grum-Tokars, James P. Schavocky, Faisal Saeed, Agnieszka Staniszewski, Andrew F. Teich, Ottavio Arancio, Adam D. Bachstetter, Scott J. Webster, Linda J. Van Eldik, George Minasov, Wayne F. Anderson, Jeffrey C. Pelletier, D. Martin Watterson

Spinal Cord and Brain Injury Research Center Faculty Publications

The first kinase inhibitor drug approval in 2001 initiated a remarkable decade of tyrosine kinase inhibitor drugs for oncology indications, but a void exists for serine/threonine protein kinase inhibitor drugs and central nervous system indications. Stress kinases are of special interest in neurological and neuropsychiatric disorders due to their involvement in synaptic dysfunction and complex disease susceptibility. Clinical and preclinical evidence implicates the stress related kinase p38αMAPK as a potential neurotherapeutic target, but isoform selective p38αMAPK inhibitor candidates are lacking and the mixed kinase inhibitor drugs that are promising in peripheral tissue disease indications have limitations for neurologic indications. Therefore, …

Tsc2/Mtorc1 Signaling Controls Paneth And Goblet Cell Differentiation In The Intestinal Epithelium, Y. Zhou, Piotr G. Rychahou, Q. Wang, Heidi L. Weiss, B. Mark Evers

Markey Cancer Center Faculty Publications

The intestinal mucosa undergoes a continual process of proliferation, differentiation and apoptosis, which is regulated by multiple signaling pathways. Notch signaling is critical for the control of intestinal stem cell maintenance and differentiation. However, the precise mechanisms involved in the regulation of differentiation are not fully understood. Previously, we have shown that tuberous sclerosis 2 (TSC2) positively regulates the expression of the goblet cell differentiation marker, MUC2, in intestinal cells. Using transgenic mice constitutively expressing a dominant negative TSC2 allele, we observed that TSC2 inactivation increased mTORC1 and Notch activities, and altered differentiation throughout the intestinal epithelium, with a marked …