Medicine and Health Sciences Commons^™

Investigating Clot-Flow Interactions By Integrating Intravital Imaging With In Silico Modeling For Analysis Of Flow, Transport, And Hemodynamic Forces, Chayut Teeraratkul, Maurizio Tomaiuolo, Timothy Stalker, Debanjan Mukherjee

Cardeza Foundation for Hematologic Research

As a blood clot forms, grows, deforms, and embolizes following a vascular injury, local clot-flow interactions lead to a highly dynamic flow environment. The local flow influences transport of biochemical species relevant for clotting, and determines the forces on the clot that in turn lead to clot deformation and embolization. Despite this central role, quantitative characterization of this dynamic clot-flow interaction and flow environment in the clot neighborhood remains a major challenge. Here, we propose an approach that integrates dynamic intravital imaging with computer geometric modeling and computational flow and transport modeling to develop a unified in silico framework to …

Xtx101, A Tumor-Activated, Fc-Enhanced Anti-Ctla-4 Monoclonal Antibody, Demonstrates Tumor-Growth Inhibition And Tumor-Selective Pharmacodynamics In Mouse Models Of Cancer, Kurt A. Jenkins, Miso Park, Magali Pederzoli-Ribeil, Ugur Eskiocak, Parker Johnson, Wilson Guzman, Megan Mclaughlin, Deborah Moore-Lai, Caitlin O'Toole, Zhen Liu, Benjamin Nicholson, Veronica Flesch, Huawei Qiu, Tim Clackson, Ronan C. O'Hagan, Ulrich Rodeck, Margaret Karow, Jennifer O'Neil, John C. Williams

Department of Dermatology and Cutaneous Biology Faculty Papers

INTRODUCTION: The clinical benefit of the anti-CTLA-4 monoclonal antibody (mAb) ipilimumab has been well established but limited by immune-related adverse events, especially when ipilimumab is used in combination with anti-PD-(L)1 mAb therapy. To overcome these limitations, we have developed XTX101, a tumor-activated, Fc-enhanced anti-CTLA-4 mAb.

METHODS: XTX101 consists of an anti-human CTLA-4 mAb covalently linked to masking peptides that block the complementarity-determining regions, thereby minimizing the mAb binding to CTLA-4. The masking peptides are designed to be released by proteases that are typically dysregulated within the tumor microenvironment (TME), resulting in activation of XTX101 intratumorally. Mutations within the Fc region …

Functional Assessment Of Missense Variants In The Abcc6 Gene Implicated In Pseudoxanthoma Elasticum, A Heritable Ectopic Mineralization Disorder., Luke Kowal, Jianhe Huang, Hongbin Luo, Jagmohan Singh, Adam E Snook, Jouni Uitto, Qiaoli Li

Department of Pharmacology and Experimental Therapeutics Faculty Papers

Pseudoxanthoma elasticum, a heritable multisystem ectopic mineralization disorder, is caused by inactivating mutations in the ABCC6 gene. The encoded protein, ABCC6, a transmembrane transporter, has a specialized efflux function in hepatocytes by contributing to plasma levels of inorganic pyrophosphate, a potent inhibitor of mineralization in soft connective tissues. Reduced plasma inorganic pyrophosphate levels underlie the ectopic mineralization in pseudoxanthoma elasticum. In this study, we characterized the pathogenicity of three human ABCC6 missense variants using an adenovirus-mediated liver-specific ABCC6 transgene expression system in an Abcc6

Inactivated Rabies Virus Vectored Sars-Cov-2 Vaccine Prevents Disease In A Syrian Hamster Model., Drishya Kurup, Delphine C Malherbe, Christoph Wirblich, Rachael Lambert, Adam J Ronk, Leila Zabihi Diba, Alexander Bukreyev, Matthias J. Schnell

Department of Microbiology and Immunology Faculty Papers

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emergent coronavirus that has caused a worldwide pandemic. Although human disease is often asymptomatic, some develop severe illnesses such as pneumonia, respiratory failure, and death. There is an urgent need for a vaccine to prevent its rapid spread as asymptomatic infections accounting for up to 40% of transmission events. Here we further evaluated an inactivated rabies vectored SARS-CoV-2 S1 vaccine CORAVAX in a Syrian hamster model. CORAVAX adjuvanted with MPLA-AddaVax, a TRL4 agonist, induced high levels of neutralizing antibodies and generated a strong Th1-biased immune response. Vaccinated hamsters were protected from …

Ifn-Β Acts On Monocytes To Ameliorate Cns Autoimmunity By Inhibiting Proinflammatory Cross-Talk Between Monocytes And Th Cells., Javad Rasouli, Giacomo Casella, Larissa Ishikawa, Rodolfo Thome, Alexandra Boehm, Adam Ertel, Carolina R Melo-Silva, Elisabeth R. Mari, Patrizia Porazzi, Weifeng Zhang, Dan Xiao, Luis J. Sigal, Paolo Fortina, Guang-Xian Zhang, A M Rostami, Bogoljub Ciric

Department of Neurology Faculty Papers

IFN-β has been the treatment for multiple sclerosis (MS) for almost three decades, but understanding the mechanisms underlying its beneficial effects remains incomplete. We have shown that MS patients have increased numbers of GM-CSF+ Th cells in circulation, and that IFN-β therapy reduces their numbers. GM-CSF expression by myelin-specific Th cells is essential for the development of experimental autoimmune encephalomyelitis (EAE), an animal model of MS. These findings suggested that IFN-β therapy may function via suppression of GM-CSF production by Th cells. In the current study, we elucidated a feedback loop between monocytes and Th cells that amplifies autoimmune neuroinflammation, …

Cigarette Smoke Initiates Oxidative Stress-Induced Cellular Phenotypic Modulation Leading To Cerebral Aneurysm Pathogenesis., Robert M. Starke, John W. Thompson, Muhammad S. Ali, Crissey L. Pascale, Alejandra Martinez Lege, Dale Ding, Nohra Chalouhi, David M. Hasan, Pascal Jabbour, Gary K Owens, Michal Toborek, Joshua M. Hare, Aaron S. Dumont

Department of Neurosurgery Faculty Papers

OBJECTIVE: Cigarette smoke exposure (CSE) is a risk factor for cerebral aneurysm (CA) formation, but the molecular mechanisms are unclear. Although CSE is known to contribute to excess reactive oxygen species generation, the role of oxidative stress on vascular smooth muscle cell (VSMC) phenotypic modulation and pathogenesis of CAs is unknown. The goal of this study was to investigate whether CSE activates a NOX (NADPH oxidase)-dependent pathway leading to VSMC phenotypic modulation and CA formation and rupture.

APPROACH AND RESULTS: In cultured cerebral VSMCs, CSE increased expression of NOX1 and reactive oxygen species which preceded upregulation of proinflammatory/matrix remodeling genes …

Effect Of The Butyrate Prodrug Pivaloyloxymethyl Butyrate (An9) On A Mouse Model For Spinal Muscular Atrophy., Jonathan D. Edwards, Matthew E.R. Butchbach

Department of Pediatrics Faculty Papers

Spinal muscular atrophy (SMA) is an early-onset motor neuron disease that leads to loss of muscle function. Butyrate (BA)-based compounds markedly improve the survival and motor phenotype of SMA mice. In this study, we examine the protective effects of the BA prodrug pivaloyloxymethyl butyrate (AN9) on the survival of SMNΔ7 SMA mice. Oral administration of AN9 beginning at PND04 almost doubled the average lifespan of SMNΔ7 SMA mice. AN9 treatment also increased the growth rate of SMNΔ7 SMA mice when compared to vehicle-treated SMNΔ7 SMA mice. In conclusion, BA prodrugs like AN9 have ameliorative effects on SMNΔ7 SMA mice.

Tau Phosphorylation At Alzheimer's Disease-Related Ser356 Contributes To Tau Stabilization When Par-1/Mark Activity Is Elevated., Kanae Ando, Mikiko Oka, Yosuke Ohtake, Motoki Hayashishita, Sawako Shimizu, Shin-Ichi Hisanaga, Koichi M. Iijima

Department of Neuroscience Faculty Papers

Abnormal phosphorylation of the microtubule-associated protein tau is observed in many neurodegenerative diseases, including Alzheimer's disease (AD). AD-related phosphorylation of two tau residues, Ser262 and Ser356, by PAR-1/MARK stabilizes tau in the initial phase of mismetabolism, leading to subsequent phosphorylation events, accumulation, and toxicity. However, the relative contribution of phosphorylation at each of these sites to tau stabilization has not yet been elucidated. In a Drosophila model of human tau toxicity, we found that tau was phosphorylated at Ser262, but not at Ser356, and that blocking Ser262 phosphorylation decreased total tau levels. By contrast, when PAR-1 was co-overexpressed with tau, …

Obesity-Induced Colorectal Cancer Is Driven By Caloric Silencing Of The Guanylin-Gucy2c Paracrine Signaling Axis., Jieru E. Lin, Francheska Colon-Gonzalez, Erik S. Blomain, Gilbert W. Kim, Amanda Aing, Brian Stoecker, Justin Rock, Adam E. Snook, Tingting Zhan, Terry M. Hyslop, Michal Tomczak, Richard S. Blumberg, Scott A. Waldman

Department of Pharmacology and Experimental Therapeutics Faculty Papers

Obesity is a well-known risk factor for colorectal cancer but precisely how it influences risks of malignancy remains unclear. During colon cancer development in humans or animals, attenuation of the colonic cell surface receptor guanylyl cyclase C (GUCY2C) that occurs due to loss of its paracrine hormone ligand guanylin contributes universally to malignant progression. In this study, we explored a link between obesity and GUCY2C silencing in colorectal cancer. Using genetically engineered mice on different diets, we found that diet-induced obesity caused a loss of guanylin expression in the colon with subsequent GUCY2C silencing, epithelial dysfunction, and tumorigenesis. Mechanistic investigations …

Loss Of Vglut3 Produces Circadian-Dependent Hyperdopaminergia And Ameliorates Motor Dysfunction And L-Dopa-Mediated Dyskinesias In A Model Of Parkinson's Disease., Christopher B. Divito, Kathy Steece-Collier, Daniel T. Case, Sean-Paul G. Williams, Jennifer A. Stancati, Lianteng Zhi, Maria E. Rubio, Caryl E. Sortwell, Timothy J. Collier, David Sulzer, Robert H. Edwards, Hui Zhang, Rebecca P. Seal

Department of Neuroscience Faculty Papers

UNLABELLED: The striatum is essential for many aspects of mammalian behavior, including motivation and movement, and is dysfunctional in motor disorders such as Parkinson's disease. The vesicular glutamate transporter 3 (VGLUT3) is expressed by striatal cholinergic interneurons (CINs) and is thus well positioned to regulate dopamine (DA) signaling and locomotor activity, a canonical measure of basal ganglia output. We now report that VGLUT3 knock-out (KO) mice show circadian-dependent hyperlocomotor activity that is restricted to the waking cycle and is due to an increase in striatal DA synthesis, packaging, and release. Using a conditional VGLUT3 KO mouse, we show that deletion …

Human Ips Cell-Derived Astrocyte Transplants Preserve Respiratory Function After Spinal Cord Injury., Ke Li, Elham Javed, Daniel Scura, Tamara J. Hala, Suneil Seetharam, Aditi Falnikar, Jean-Philippe Richard, Ashley Chorath, Nicholas J. Maragakis, Megan C. Wright, Angelo C. Lepore

Department of Neuroscience Faculty Papers

Transplantation-based replacement of lost and/or dysfunctional astrocytes is a promising therapy for spinal cord injury (SCI) that has not been extensively explored, despite the integral roles played by astrocytes in the central nervous system (CNS). Induced pluripotent stem (iPS) cells are a clinically-relevant source of pluripotent cells that both avoid ethical issues of embryonic stem cells and allow for homogeneous derivation of mature cell types in large quantities, potentially in an autologous fashion. Despite their promise, the iPS cell field is in its infancy with respect to evaluating in vivo graft integration and therapeutic efficacy in SCI models. Astrocytes express …

Structure-Based Screen Identifies A Potent Small Molecule Inhibitor Of Stat5a/B With Therapeutic Potential For Prostate Cancer And Chronic Myeloid Leukemia., Zhiyong Liao, Lei Gu, Jenny Vergalli, Samanta A. Mariani, Marco De Dominici, Ravi K. Lokareddy, Ayush Dagvadorj, Puranik Purushottamachar, Peter A. Mccue, Edouard J. Trabulsi, Costas D. Lallas, Shilpa Gupta, Elyse Ellsworth, Shauna Blackmon, Adam Ertel, Paolo Fortina, Benjamin E. Leiby, Guanjun Xia, Hallgeir Rui, David T. Hoang, Leonard G Gomella, Gino Cingolani, Vincent Njar, Nagarajan Pattabiraman, Bruno Calabretta, Marja T. Nevalainen

Department of Cancer Biology Faculty Papers

Bypassing tyrosine kinases responsible for Stat5a/b phosphorylation would be advantageous for therapy development for Stat5a/b-regulated cancers. Here, we sought to identify small molecule inhibitors of Stat5a/b for lead optimization and therapy development for prostate cancer and Bcr-Abl-driven leukemias. In silico screening of chemical structure databases combined with medicinal chemistry was used for identification of a panel of small molecule inhibitors to block SH2 domain-mediated docking of Stat5a/b to the receptor-kinase complex and subsequent phosphorylation and dimerization. We tested the efficacy of the lead compound IST5-002 in experimental models and patient samples of two known Stat5a/b-driven cancers, prostate cancer and chronic …

Nf-Κb Regulation Of C-Flip Promotes Tnfα-Mediated Raf Inhibitor Resistance In Melanoma., Yongping Shao, Kaitlyn Le, Hanyin Cheng, Andrew E. Aplin

Department of Cancer Biology Faculty Papers

Targeted inhibitors elicit heterogeneous clinical responses in genetically stratified groups of patients. Although most studies focus on tumor intrinsic properties, factors in the tumor microenvironment were recently found to modulate the response to inhibitors. Here, we show that in cutaneous BRAF V600E melanoma, the cytokine tumor necrosis factor-α (TNFα) blocks RAF inhibitor-induced apoptosis via activation of NF-κB. Several NF-κB-dependent factors are upregulated following TNFα and RAF inhibitor treatment. Of these factors, we show that death receptor inhibitor cellular caspase 8 (FLICE)-like inhibitory protein (c-FLIP) is required for TNFα-induced protection against RAF inhibitor. Overexpression of c-FLIP_S or c-FLIP_L isoform decreased RAF …

Effects Of Chronic Manganese Exposure On Attention And Working Memory In Non-Human Primates., Jay S. Schneider, Charles Williams, Mark Ault, Tomás R. Guilarte

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Manganese (Mn) is essential for a variety of physiological processes, but at elevated levels, can be neurotoxic. While cognitive dysfunction has been recently appreciated to occur as a result of chronic Mn exposures, it is still unclear as to which cognitive domains are most susceptible to disruption by Mn exposure. We previously described early appearing Mn-induced changes in performance on a paired associate learning task in monkeys chronically exposed to Mn and suggested that performance of this task might be a sensitive tool for detecting cognitive dysfunction resulting from Mn exposure. As chronic Mn exposure has been suggested to be …

Expression Of Enteropathogenic Escherichia Coli Map Is Significantly Different Than That Of Other Type Iii Secreted Effectors In Vivo., Mai Nguyen, Jason Rizvi, Gail Hecht

Department of Medicine Faculty Papers

The enteropathogenic Escherichia coli (EPEC) locus of enterocyte effacement (LEE)-encoded effectors EspF and Map are multifunctional and have an impact on the tight junction barrier while the non-LEE-encoded proteins NleH1 and NleH2 possess significant anti-inflammatory activity. In order to address the temporal expression of these important genes in vivo, their promoters were cloned upstream of the luxCDABE operon, and luciferase expression was measured in EPEC-infected mice by bioluminescence using an in vivo imaging system (IVIS). Bioluminescent images of living mice, of excised whole intestines, and of whole intestines longitudinally opened and washed were assessed. The majority of bioluminescent bacteria localized …

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 …

Pharmacologic Suppression Of Jak1/2 By Jak1/2 Inhibitor Azd1480 Potently Inhibits Il-6-Induced Experimental Prostate Cancer Metastases Formation., Lei Gu, Pooja Talati, Paraskevi Vogiatzi, Ana L Romero-Weaver, Junaid Abdulghani, Zhiyong Liao, Benjamin E. Leiby, David T. Hoang, Tuomas Mirtti, Kalle Alanen, Michael Zinda, Dennis Huszar, Marja T. Nevalainen

Department of Medical Oncology Faculty Papers

Metastatic prostate cancer is lethal and lacks effective strategies for prevention or treatment, requiring novel therapeutic approaches. Interleukin-6 (IL-6) is a cytokine that has been linked with prostate cancer pathogenesis by multiple studies. However, the direct functional roles of IL-6 in prostate cancer growth and progression have been unclear. In the present study, we show that IL-6 is produced in distant metastases of clinical prostate cancers. IL-6-activated signaling pathways in prostate cancer cells induced a robust 7-fold increase in metastases formation in nude mice. We further show that IL-6 promoted migratory prostate cancer cell phenotype, including increased prostate cancer cell …

Efficient B Cell Responses To Borrelia Hermsii Infection Depend On Baff And Baffr But Not Taci., Gregory S. Dickinson, Phd, Guizhi Sun, Richard J Bram, Kishore Alugupalli

Department of Microbiology and Immunology Faculty Papers

T cell-independent antibody responses develop rapidly, within 3 to 4 days, and are critical for preventing blood-borne pathogens from evolving into life-threatening infections. The interaction of BAFF, also known as BLyS, with its receptors BAFFR and TACI on B cells is critical for B cell homeostasis and function. Using a synthetic polysaccharide antigen, it has previously been shown that TACI is critical for T cell-independent antibody responses. To examine the role of BAFFR and TACI in T cell-independent antibody responses to an active infection, we utilized the Borrelia hermsii infection system. In this infection system, T cell-independent responses mediated by …

Defects In Synapse Structure And Function Precede Motor Neuron Degeneration In Drosophila Models Of Fus-Related Als., Mohammad Shahidullah, Sylvain J Le Marchand, Hong Fei, Jiaming Zhang, Udai Bhan Pandey, Matthew B. Dalva, Piera Pasinelli, Irwin B. Levitan

Department of Neuroscience Faculty Papers

Amyotrophic lateral sclerosis (ALS) is an adult-onset neurodegenerative disease that leads invariably to fatal paralysis associated with motor neuron degeneration and muscular atrophy. One gene associated with ALS encodes the DNA/RNA-binding protein Fused in Sarcoma (FUS). There now exist two Drosophila models of ALS. In one, human FUS with ALS-causing mutations is expressed in fly motor neurons; in the other, the gene cabeza (caz), the fly homolog of FUS, is ablated. These FUS-ALS flies exhibit larval locomotor defects indicative of neuromuscular dysfunction and early death. The locus and site of initiation of this neuromuscular dysfunction remain unclear. We show here …

Glutamine Supplementation Alleviates Vasculopathy And Corrects Metabolic Profile In An In Vivo Model Of Endothelial Cell Dysfunction., Francesco Addabbo, Qiuying Chen, Dhara P Patel, May Rabadi, Brian Ratliff, Frank Zhang, Jean-Francois Jasmin, Michael Wolin, Michael Lisanti, Steven S Gross, Michael S Goligorsky

Kimmel Cancer Center Faculty Papers

Endothelial Cell Dysfunction (ECD) is a recognized harbinger of a host of chronic cardiovascular diseases. Using a mouse model of ECD triggered by treatment with L-Nω-methylarginine (L-NMMA), we previously demonstrated that renal microvasculature displays a perturbed protein profile, including diminished expression of two key enzymes of the Krebs cycle associated with a Warburg-type suppression of mitochondrial metabolism. We hypothesized that supplementation with L-glutamine (GLN), that can enter the Krebs cycle downstream this enzymatic bottleneck, would normalize vascular function and alleviate mitochondrial dysfunction. To test this hypothesis, mice with chronic L-NMMA-induced ECD were co-treated with GLN at different concentrations for 2 …

Necrostatin-1 Analogues: Critical Issues On The Specificity, Activity And In Vivo Use In Experimental Disease Models., N Takahashi, L Duprez, S Grootjans, A Cauwels, W Nerinckx, J B Duhadaway, V Goossens, R Roelandt, F Van Hauwermeiren, C Libert, W Declercq, N Callewaert, G C Prendergast, A Degterev, J Yuan, P Vandenabeele

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Necrostatin-1 (Nec-1) is widely used in disease models to examine the contribution of receptor-interacting protein kinase (RIPK) 1 in cell death and inflammation. We studied three Nec-1 analogs: Nec-1, the active inhibitor of RIPK1, Nec-1 inactive (Nec-1i), its inactive variant, and Nec-1 stable (Nec-1s), its more stable variant. We report that Nec-1 is identical to methyl-thiohydantoin-tryptophan, an inhibitor of the potent immunomodulatory enzyme indoleamine 2,3-dioxygenase (IDO). Both Nec-1 and Nec-1i inhibited human IDO, but Nec-1s did not, as predicted by molecular modeling. Therefore, Nec-1s is a more specific RIPK1 inhibitor lacking the IDO-targeting effect. Next, although Nec-1i was ∼100 × …

Determining The Absolute Requirement Of G Protein-Coupled Receptor Kinase 5 For Pathological Cardiac Hypertrophy: Short Communication., Jessica I Gold, Erhe Gao, Xiying Shang, Richard T Premont, Walter J Koch

Center for Translational Medicine Faculty Papers

RATIONALE: Heart failure (HF) is often the end phase of maladaptive cardiac hypertrophy. A contributing factor is activation of a hypertrophic gene expression program controlled by decreased class II histone deacetylase (HDAC) transcriptional repression via HDAC phosphorylation. Cardiac-specific overexpression of G proteinen-coupled receptor kinase-5 (GRK5) has previously been shown to possess nuclear activity as a HDAC5 kinase, promoting an intolerance to in vivo ventricular pressure overload; however, its endogenous requirement in adaptive and maladaptive hypertrophy remains unknown.

OBJECTIVE: We used mouse models with global or cardiomyocyte-specific GRK5 gene deletion to determine the absolute requirement of endogenous GRK5 for cardiac hypertrophy …

Nociceptive Neuropeptide Increases And Periorbital Allodynia In A Model Of Traumatic Brain Injury., Melanie B. Elliott, Michael L. Oshinsky, Peter S. Amenta, Olatilewa Awe, Jack I. Jallo

Department of Neurosurgery Faculty Papers

OBJECTIVE: This study tests the hypothesis that injury to the somatosensory cortex is associated with periorbital allodynia and increases in nociceptive neuropeptides in the brainstem in a mouse model of controlled cortical impact (CCI) injury.

METHODS: Male C57BL/6 mice received either CCI or craniotomy-only followed by weekly periorbital von Frey (mechanical) sensory testing for up to 28 days post-injury. Mice receiving an incision only and naïve mice were included as control groups. Changes in calcitonin gene-related peptide (CGRP) and substance P (SP) within the brainstem were determined using enzyme-linked immunosorbent assay and immunohistochemistry, respectively. Activation of ionized calcium-binding adaptor molecule-1-labeled …

Essential Role Of Caveolin-3 In Adiponectin Signalsome Formation And Adiponectin Cardioprotection., Yajing Wang, Xiaoliang Wang, Jean-François Jasmin, Wayne Bond Lau, Rong Li, Yuexin Yuan, Wei Yi, Kurt Chuprun, Michael P. Lisanti, Walter J Koch, Erhe Gao, Xin-Liang Ma

Department of Emergency Medicine Faculty Papers

OBJECTIVE: Adiponectin (APN) system malfunction is causatively related to increased cardiovascular morbidity/mortality in diabetic patients. The aim of the current study was to investigate molecular mechanisms responsible for APN transmembrane signaling and cardioprotection.

METHODS AND RESULTS: Compared with wild-type mice, caveolin-3 knockout (Cav-3KO) mice exhibited modestly increased myocardial ischemia/reperfusion injury (increased infarct size, apoptosis, and poorer cardiac function recovery; P

CONCLUSIONS: Taken together, these results demonstrated for the first time that Cav-3 plays an essential role in APN transmembrane signaling and APN anti-ischemic/cardioprotective actions.

Loss Of Αt-Catenin Alters The Hybrid Adhering Junctions In The Heart And Leads To Dilated Cardiomyopathy And Ventricular Arrhythmia Following Acute Ischemia., Jifen Li, Steven Goossens, Jolanda Van Hengel, Erhe Gao, Lan Cheng, Koen Tyberghein, Xiying Shang, Riet De Rycke, Frans Van Roy, Glenn L Radice

Center for Translational Medicine Faculty Papers

It is generally accepted that the intercalated disc (ICD) required for mechano-electrical coupling in the heart consists of three distinct junctional complexes: adherens junctions, desmosomes and gap junctions. However, recent morphological and molecular data indicate a mixing of adherens junctional and desmosomal components, resulting in a 'hybrid adhering junction' or 'area composita'. The α-catenin family member αT-catenin, part of the N-cadherin-catenin adhesion complex in the heart, is the only α-catenin that interacts with the desmosomal protein plakophilin-2 (PKP2). Thus, it has been postulated that αT-catenin might serve as a molecular integrator of the two adhesion complexes in the area composita. …

Pressure-Overload-Induced Subcellular Relocalization/Oxidation Of Soluble Guanylyl Cyclase In The Heart Modulates Enzyme Stimulation., Emily J Tsai, Yuchuan Liu, Norimichi Koitabashi, Djahida Bedja, Thomas Danner, Jean-Francois Jasmin, Michael P Lisanti, Andreas Friebe, Eiki Takimoto, David A Kass

Department of Stem Cell Biology and Regenerative Medicine Faculty Papers & Presentations

RATIONALE: Soluble guanylyl cyclase (sGC) generates cyclic guanosine monophophate (cGMP) upon activation by nitric oxide (NO). Cardiac NO-sGC-cGMP signaling blunts cardiac stress responses, including pressure-overload-induced hypertrophy. The latter itself depresses signaling through this pathway by reducing NO generation and enhancing cGMP hydrolysis.

OBJECTIVE: We tested the hypothesis that the sGC response to NO also declines with pressure-overload stress and assessed the role of heme-oxidation and altered intracellular compartmentation of sGC as potential mechanisms.

METHODS AND RESULTS: C57BL/6 mice subjected to transverse aortic constriction (TAC) developed cardiac hypertrophy and dysfunction. NO-stimulated sGC activity was markedly depressed, whereas NO- and heme-independent sGC …

Uterine Dysfunction In Biglycan And Decorin Deficient Mice Leads To Dystocia During Parturition., Zhiping Wu, Abraham W Aron, Elyse E Macksoud, Renato V Iozzo, Chi-Ming Hai, Beatrice E Lechner

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Cesarean birth rates are rising. Uterine dysfunction, the exact mechanism of which is unknown, is a common indication for Cesarean delivery. Biglycan and decorin are two small leucine-rich proteoglycans expressed in the extracellular matrix of reproductive tissues and muscle. Mice deficient in biglycan display a mild muscular dystrophy, and, along with mice deficient in decorin, are models of Ehlers-Danlos Syndrome, a connective tissue anomaly associated with uterine rupture. As a variant of Ehlers-Danlos Syndrome is caused by a genetic mutation resulting in abnormal biglycan and decorin secretion, we hypothesized that biglycan and decorin play a role in uterine function. Thus, …

Temporal Changes In Innate Immune Signals In A Rat Model Of Alcohol Withdrawal In Emotional And Cardiorespiratory Homeostatic Nuclei., Kate Freeman, Anthony Brureau, Rajanikanth Vadigepalli, Mary M Staehle, Melanie M Brureau, Gregory E Gonye, Jan B Hoek, D Craig Hooper, James S Schwaber

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: Chronic alcohol use changes the brain's inflammatory state. However, there is little work examining the progression of the cytokine response during alcohol withdrawal, a period of profound autonomic and emotional upset. This study examines the inflammatory response in the central nucleus of the amygdala (CeA) and dorsal vagal complex (DVC), brain regions neuroanatomically associated with affective and cardiorespiratory regulation in an in vivo rat model of withdrawal following a single chronic exposure.

METHODS: For qRT-PCR studies, we measured the expression of TNF-α, NOS-2, Ccl2 (MCP-1), MHC II invariant chain CD74, and the TNF receptor Tnfrsf1a in CeA and DVC …

Administration Of Bone Marrow Derived Mesenchymal Stem Cells Into The Liver: Potential To Rescue Pseudoxanthoma Elasticum In A Mouse Model (Abcc6-/-)., Qiujie Jiang, Shunsuke Takahagi, Jouni Uitto

Department of Dermatology and Cutaneous Biology Faculty Papers

Pseudoxanthoma elasticum (PXE) is a heritable ectopic mineralization disorder caused by loss-of-function mutations in the ABCC6 gene which is primarily expressed in the liver. There is currently no effective treatment for PXE. In this study, we characterized bone marrow derived mesenchymal stem cells (MSCs) and evaluated their ability to contribute to liver regeneration, with the aim to rescue PXE phenotype. The MSCs, isolated from GFP-transgenic mice by magnetic cell sorting, were shown to have high potential for hepatic differentiation, with expression of Abcc6, in culture. These cells were transplanted into the livers of 4-week-old immunodeficient Abcc6⁻/⁻ mice by intrasplenic injection …

Testosterone Treatment Fails To Accelerate Disease In A Transgenic Mouse Model Of Spinal And Bulbar Muscular Atrophy., Erica S Chevalier-Larsen, Diane E Merry

Department of Biochemistry and Molecular Biology Faculty Papers

Evidence from multiple animal models demonstrates that testosterone plays a crucial role in the progression of symptoms in spinal and bulbar muscular atrophy (SBMA), a condition that results in neurodegeneration and muscle atrophy in affected men. Mice bearing a transgene encoding a human androgen receptor (AR) that contains a stretch of 112 glutamines (expanded polyglutamine tract; AR112Q mice) reproduce several aspects of the human disease. We treated transgenic male AR112Q mice with testosterone for 6 months. Surprisingly, testosterone treatment of AR112Q males did not exacerbate the disease. Although transgenic AR112Q males exhibited functional deficits when compared with non-transgenics, long-term testosterone …