Digital Commons Network^™

Cell-Autonomous Effects Of Apoe4 In Restricting Microglial Response In Brain Homeostasis And Alzheimer’S Disease, Chia-Chen Liu, Na Wang, Yuanxin Chen, Yasuteru Inoue, Francis Shue, Yingxue Ren, Minghui Wang, Wenhui Qiao, Tadafumi C Ikezu, Zonghua Li, Jing Zhao, Yuka Martens, Sydney V Doss, Cassandra L Rosenberg, Suren Jeevaratnam, Lin Jia, Ana-Caroline Raulin, Fangfang Qi, Yiyang Zhu, Alla Alnobani, Joshua Knight, Yixing Chen, Cynthia Linares, Aishe Kurti, John D Fryer, Bin Zhang, Long-Jun Wu, Betty Y S Kim, Guojun Bu

Faculty, Staff and Student Publications

Microglial involvement in Alzheimer's disease (AD) pathology has emerged as a risk-determining pathogenic event. While apolipoprotein E (APOE) is known to modify AD risk, it remains unclear how microglial apoE impacts brain cognition and AD pathology. Here, using conditional mouse models expressing apoE isoforms in microglia and central nervous system-associated macrophages (CAMs), we demonstrate a cell-autonomous effect of apoE3-mediated microglial activation and function, which are negated by apoE4. Expression of apoE3 in microglia/CAMs improves cognitive function, increases microglia surrounding amyloid plaque and reduces amyloid pathology and associated toxicity, whereas apoE4 expression either compromises or has no effects on these outcomes …

Adavosertib Enhances Antitumor Activity Of Trastuzumab Deruxtecan In Her2-Expressing Cancers, Timothy P Diperi, Kurt W Evans, Maria Gabriela Raso, Ming Zhao, Yasmeen Q Rizvi, Xiaofeng Zheng, Bailiang Wang, Bryce P Kirby, Kathleen Kong, Michael Kahle, Timothy A Yap, Ecaterina E Dumbrava, Jaffer A Ajani, Siqing Fu, Khandan Keyomarsi, Funda Meric-Bernstam

Faculty, Staff and Student Publications

PURPOSE: Cyclin E (CCNE1) has been proposed as a biomarker of sensitivity to adavosertib, a Wee1 kinase inhibitor, and a mechanism of resistance to HER2-targeted therapy.

EXPERIMENTAL DESIGN: Copy number and genomic sequencing data from The Cancer Genome Atlas and MD Anderson Cancer Center databases were analyzed to assess ERBB2 and CCNE1 expression. Molecular characteristics of tumors and patient-derived xenografts (PDX) were assessed by next-generation sequencing, whole-exome sequencing, fluorescent in situ hybridization, and IHC. In vitro, CCNE1 was overexpressed or knocked down in HER2+ cell lines to evaluate drug combination efficacy. In vivo, NSG mice bearing PDXs were subjected to …

Improved Humoral Immunity And Protection Against Influenza Virus Infection With A 3d Porous Biomaterial Vaccine, Hiromi Miwa, Olivia Q Antao, Kindra M Kelly-Scumpia, Sevana Baghdasarian, Daniel P Mayer, Lily Shang, Gina M Sanchez, Maani M Archang, Philip O Scumpia, Jason S Weinstein, Dino Di Carlo

Faculty, Staff and Student Publications

New vaccine platforms that activate humoral immunity and generate neutralizing antibodies are required to combat emerging pathogens, including influenza virus. A slurry of antigen-loaded hydrogel microparticles that anneal to form a porous scaffold with high surface area for antigen uptake by infiltrating immune cells as the biomaterial degrades is demonstrated to enhance humoral immunity. Antigen-loaded-microgels elicited a robust cellular humoral immune response, with increased CD4

The Androgen Receptor Does Not Directly Regulate The Transcription Of Dna Damage Response Genes, Joshua D Samuels, Katelyn A Moore, Hannah E Ennerfelt, Alexis M Johnson, Adeline E Walsh, Richard J Price, John R Lukens

Faculty, Staff and Student Publications

INTRODUCTION: Mutations in INPP5D, which encodes for the SH2-domain-containing inositol phosphatase SHIP-1, have recently been linked to an increased risk of developing late-onset Alzheimer's disease. While INPP5D expression is almost exclusively restricted to microglia in the brain, little is known regarding how SHIP-1 affects neurobiology or neurodegenerative disease pathogenesis.

METHODS: We generated and investigated 5xFAD Inpp5d

RESULTS: SHIP-1 deletion in microglia led to substantially enhanced recruitment of microglia to Aβ plaques, altered microglial gene expression, and marked improvements in neuronal health. Further, SHIP-1 loss enhanced microglial plaque containment and Aβ engulfment when compared to microglia from Cre-negative 5xFAD Inpp5d

DISCUSSION: …

Animal Models In Systemic Sclerosis: An Update, Xiongjie Bi, Tingting Mills, Minghua Wu

Faculty, Staff and Student Publications

Purpose of review: Systemic sclerosis (SSc) is a multisystem autoimmune connective tissue disease characterized by early inflammation followed by excessive fibrosis in the skin and internal organs. Enhancing our comprehension of SSc pathogenesis is essential to develop effective therapeutic strategies. Animal models that mimic one or more aspects of SSc have been proven to be a valuable resource for investigating disease mechanisms. This review aims to provide an updated overview of the existing SSc animal models and the potentially relevant pathways to SSc pathogenesis.

Recent findings: This review focuses on the most recently generated and investigated animal models, which delve …

Optogenetic Stimulation Of Ca1 Pyramidal Neurons At Theta Enhances Recognition Memory In Brain Injured Animals, John I Broussard, John B Redell, Jing Zhao, Rebecca West, Ryota Homma, Pramod K Dash

Faculty, Staff and Student Publications

The hippocampus plays a prominent role in learning and memory formation. The functional integrity of this structure is often compromised after traumatic brain injury (TBI), resulting in lasting cognitive dysfunction. The activity of hippocampal neurons, particularly place cells, is coordinated by local theta oscillations. Previous studies aimed at examining hippocampal theta oscillations after experimental TBI have reported disparate findings. Using a diffuse brain injury model, the lateral fluid percussion injury (FPI; 2.0 atm), we report a significant reduction in hippocampal theta power that persists for at least three weeks after injury. We questioned whether the behavioral deficit associated with this …

Loss Of Adar1 In Macrophages In Combination With Interferon Gamma Suppresses Tumor Growth By Remodeling The Tumor Microenvironment, Weiwei Lin, Yikai Luo, Jie Wu, Haowan Zhang, Ge Jin, Chahua Guo, Hang Zhou, Han Liang, Xiaoyan Xu

Faculty, Staff and Student Publications

Background: ADAR1, the major enzyme for RNA editing, has emerged as a tumor-intrinsic key determinant for cancer immunotherapy efficacy through modulating interferon-mediated innate immunity. However, the role of ADAR1 in innate immune cells such as macrophages remains unknown.

Methods: We first analyzed publicly accessible patient-derived single-cell RNA-sequencing and perturbed RNA sequencing data to elucidate the ADAR1 expression and function in macrophages. Subsequently, we evaluated the combined effects of ADAR1 conditional knockout in macrophages and interferon (IFN)-γ treatment on tumor growth in three distinct disease mouse models: LLC for lung cancer, B16-F10 for melanoma, and MC38 for colon cancer. To gain …

Interplay Of Hypoxia-Inducible Factors And Oxygen Therapy In Cardiovascular Medicine, Yafen Liang, Wei Ruan, Yandong Jiang, Richard Smalling, Xiaoyi Yuan, Holger K Eltzschig

Faculty, Staff and Student Publications

Mammals have evolved to adapt to differences in oxygen availability. Although systemic oxygen homeostasis relies on respiratory and circulatory responses, cellular adaptation to hypoxia involves the transcription factor hypoxia-inducible factor (HIF). Given that many cardiovascular diseases involve some degree of systemic or local tissue hypoxia, oxygen therapy has been used liberally over many decades for the treatment of cardiovascular disorders. However, preclinical research has revealed the detrimental effects of excessive use of oxygen therapy, including the generation of toxic oxygen radicals or attenuation of endogenous protection by HIFs. In addition, investigators in clinical trials conducted in the past decade have …

Experimentally Induced Active And Quiet Sleep Engage Non-Overlapping Transcriptional Programs In Drosophila, Niki Anthoney, Lucy Tainton-Heap, Hang Luong, Eleni Notaras, Amber B Kewin, Qiongyi Zhao, Trent Perry, Philip Batterham, Paul J Shaw, Bruno Van Swinderen

2020-Current year OA Pubs

Sleep in mammals can be broadly classified into two different physiological categories: rapid eye movement (REM) sleep and slow-wave sleep (SWS), and accordingly REM and SWS are thought to achieve a different set of functions. The fruit fly

Bhlhe40 Mediates Cross-Talk Between Pathogenic Th17 Cells And Myeloid Cells During Experimental Autoimmune Encephalomyelitis, Melissa E Cook, Irina Shchukina, Chih-Chung Lin, Tara R Bradstreet, Elizabeth A Schwarzkopf, Nicholas N Jarjour, Ashlee M Webber, Konstantin Zaitsev, Maxim N Artyomov, Brian T Edelson

2020-Current year OA Pubs

TH17 cells are implicated in the pathogenesis of multiple sclerosis and experimental autoimmune encephalomyelitis (EAE). We previously reported that the transcription factor basic helix-loop-helix family member e40 (BHLHE40) marks cytokine-producing pathogenic TH cells during EAE, and that its expression in T cells is required for clinical disease. In this study, using dual reporter mice, we show BHLHE40 expression within TH1/17 and ex-TH17 cells following EAE induction. Il17a-Cre-mediated deletion of BHLHE40 in TH cells led to less severe EAE with reduced TH cell cytokine production. Characterization of the leukocytes in the CNS during EAE by single-cell RNA sequencing identified differences in …

Glut3 Promotes Macrophage Signaling And Function Via Ras-Mediated Endocytosis In Atopic Dermatitis And Wound Healing, Dong-Min Yu, Jiawei Zhao, Eunice E Lee, Dohun Kim, Ruchika Mahapatra, Elysha K Rose, Zhiwei Zhou, Calvin Hosler, Abdullah El Kurdi, Jun-Yong Choe, E Dale Abel, Gerta Hoxhaj, Kenneth D Westover, Raymond J Cho, Jeffrey B Cheng, Richard C Wang

Staff and Researcher Publications

The facilitative GLUT1 and GLUT3 hexose transporters are expressed abundantly in macrophages, but whether they have distinct functions remains unclear. We confirmed that GLUT1 expression increased after M1 polarization stimuli and found that GLUT3 expression increased after M2 stimulation in macrophages. Conditional deletion of Glut3 (LysM-Cre Glut3fl/fl) impaired M2 polarization of bone marrow-derived macrophages. Alternatively activated macrophages from the skin of patients with atopic dermatitis showed increased GLUT3 expression, and a calcipotriol-induced model of atopic dermatitis was rescued in LysM-Cre Glut3fl/fl mice. M2-like macrophages expressed GLUT3 in human wound tissues as assessed by transcriptomics and costaining, and GLUT3 expression was …

Therapeutic Implications Of Impaired Nuclear Receptor Function And Dysregulated Metabolism In Wilson’S Disease, Clavia Ruth Wooton-Kee

Faculty, Staff and Students Publications

Copper is an essential trace element that is required for the activity of many enzymes and cellular processes, including energy homeostasis and neurotransmitter biosynthesis; however, excess copper accumulation results in significant cellular toxicity. The liver is the major organ for maintaining copper homeostasis. Inactivating mutations of the copper-transporting P-type ATPase, ATP7B, result in Wilson’s disease, an autosomal recessive disorder that requires life-long medicinal therapy or liver transplantation. Current treatment protocols are limited to either sequestration of copper via chelation or reduction of copper absorption in the gut (zinc therapy). The goal of these strategies is to reduce free copper, redox …

Preterm Pigs Fed Donor Human Milk Have Greater Liver Β-Carotene Concentrations Than Pigs Fed Infant Formula, Nancy E Moran, Joshua Wade, Rachel Stroh, Barbara Stoll, Gregory Guthrie, Amy B Hair, Douglas G Burrin

Faculty, Staff and Students Publications

BACKGROUND: Milk carotenoids may support preterm infant health and neurodevelopment. Infants fed human milk often have higher blood and tissue carotenoid concentrations than infants fed carotenoid-containing infant formula (IF). Donor human milk (DHM) is a supplement to mother's own milk, used to support preterm infant nutrition.

OBJECTIVES: We tested whether tissue and plasma β-carotene concentrations would be higher in preterm pigs fed pasteurized DHM versus premature IF.

METHODS: This is a secondary analysis of samples collected from a study of the effects of enteral diet composition on necrotizing enterocolitis incidence. Preterm pigs received partial enteral feeding of either DHM (n …

The Atoh1-Cre Knock-In Allele Ectopically Labels A Subpopulation Of Amacrine Cells And Bipolar Cells In Mouse Retina, Sih-Rong Wu, Huda Y Zoghbi

Duncan NRI Faculty and Staff Publications

The retina has diverse neuronal cell types derived from a common pool of retinal progenitors. Many molecular drivers, mostly transcription factors, have been identified to promote different cell fates. In Drosophila, atonal is required for specifying photoreceptors. In mice, there are two closely related atonal homologs, Atoh1 and Atoh7. While Atoh7 is known to promote the genesis of retinal ganglion cells, there is no study on the function of Atoh1 in retinal development. Here, we crossed Atoh1^Cre/+ mice to mice carrying a Cre-dependent TdTomato reporter to track potential Atoh1-lineage neurons in retinas. We characterized a heterogeneous …

The Impact Of Vaccine-Linked Chemotherapy On Liver Health In A Mouse Model Of Chronic Trypanosoma Cruzi Infection, Duc Minh Nguyen, Cristina Poveda, Jeroen Pollet, Fabian Gusovsky, Maria Elena Bottazzi, Peter J Hotez, Kathryn Marie Jones

Faculty, Staff and Students Publications

BACKGROUND: Chagas disease, chronic infection with Trypanosoma cruzi, mainly manifests as cardiac disease. However, the liver is important for both controlling parasite burdens and metabolizing drugs. Notably, high doses of anti-parasitic drug benznidazole (BNZ) causes liver damage. We previously showed that combining low dose BNZ with a prototype therapeutic vaccine is a dose sparing strategy that effectively reduced T. cruzi induced cardiac damage. However, the impact of this treatment on liver health is unknown. Therefore, we evaluated several markers of liver health after treatment with low dose BNZ plus the vaccine therapy in comparison to a curative dose of BNZ. …

Increasing Glutathione Levels By A Novel Posttranslational Mechanism Inhibits Neuronal Hyperexcitability, Ashwini Sri Hari, Rajeswari Banerji, Li-Ping Liang, Ruth E Fulton, Christopher Quoc Huynh, Timothy Fabisiak, Pallavi Bhuyan Mcelroy, James R Roede, Manisha Patel

Faculty, Staff and Students Publications

Glutathione (GSH) depletion, and impaired redox homeostasis have been observed in experimental animal models and patients with epilepsy. Pleiotropic strategies that elevate GSH levels via transcriptional regulation have been shown to significantly decrease oxidative stress and seizure frequency, increase seizure threshold, and rescue certain cognitive deficits. Whether elevation of GSH per se alters neuronal hyperexcitability remains unanswered. We previously showed that thiols such as dimercaprol (DMP) elevate GSH via post-translational activation of glutamate cysteine ligase (GCL), the rate limiting GSH biosynthetic enzyme. Here, we asked if elevation of cellular GSH by DMP altered neuronal hyperexcitability in-vitro and in-vivo. Treatment of …

Pax3 Lineage-Specific Deletion Of Gpr161 Is Associated With Spinal Neural Tube And Craniofacial Malformations During Embryonic Development, Sung-Eun Kim, Pooja J Chothani, Rehana Shaik, Westley Pollard, Richard H Finnell

Faculty, Staff and Students Publications

Sonic hedgehog (Shh) signaling is the morphogen signaling that regulates embryonic craniofacial and neural tube development. G protein-coupled receptor 161 (Gpr161) is a negative regulator of Shh signaling, and its inactivation in mice results in embryo lethality associated with craniofacial defects and neural tube defects. However, the structural defects of later embryonic stages and cell lineages underlying abnormalities have not been well characterized due to the limited lifespan of Gpr161 null mice. We found that embryos with Pax3 lineage-specific deletion of Gpr161 presented with tectal hypertrophy (anterior dorsal neuroepithelium), cranial vault and facial bone hypoplasia (cranial neural crest), vertebral abnormalities …

A Human Mitofusin 2 Mutation Can Cause Mitophagic Cardiomyopathy, Antonietta Franco, Jiajia Li, Daniel P Kelly, Ray E Hershberger, Ali J Marian, Renate M Lewis, Moshi Song, Xiawei Dang, Alina D Schmidt, Mary E Mathyer, John R Edwards, Cristina De Guzman Strong, Gerald W Dorn

2020-Current year OA Pubs

Cardiac muscle has the highest mitochondrial density of any human tissue, but mitochondrial dysfunction is not a recognized cause of isolated cardiomyopathy. Here, we determined that the rare mitofusin (MFN) 2 R400Q mutation is 15-20× over-represented in clinical cardiomyopathy, whereas this specific mutation is not reported as a cause of MFN2 mutant-induced peripheral neuropathy, Charcot-Marie-Tooth disease type 2A (CMT2A). Accordingly, we interrogated the enzymatic, biophysical, and functional characteristics of MFN2 Q400 versus wild-type and CMT2A-causing MFN2 mutants. All MFN2 mutants had impaired mitochondrial fusion, the canonical MFN2 function. Compared to MFN2 T105M that lacked catalytic GTPase activity and exhibited normal …

Disrupting Actin Filaments Enhances Glucose-Stimulated Insulin Secretion Independent Of The Cortical Actin Cytoskeleton, Alexander J Polino, Xue Wen Ng, Rebecca Rooks, David W Piston

2020-Current year OA Pubs

Just under the plasma membrane of most animal cells lies a dense meshwork of actin filaments called the cortical cytoskeleton. In insulin-secreting pancreatic β cells, a long-standing model posits that the cortical actin layer primarily acts to restrict access of insulin granules to the plasma membrane. Here we test this model and find that stimulating β cells with pro-secretory stimuli (glucose and/or KCl) has little impact on the cortical actin layer. Chemical perturbations of actin polymerization, by either disrupting or enhancing filamentation, dramatically enhance glucose-stimulated insulin secretion. Using scanning electron microscopy, we directly visualize the cortical cytoskeleton, allowing us to …

Dominant Negative Variants In Kif5b Cause Osteogenesis Imperfecta Via Down Regulation Of Mtor Signaling, Ronit Marom, Anika Lindsey, Jacob Lesinski, Michael L. Nonet, Jian Chen, Dustin Baldridge, Gary A. Silverman, Stephen C. Pak, Et Al.

2020-Current year OA Pubs

BACKGROUND: Kinesin motor proteins transport intracellular cargo, including mRNA, proteins, and organelles. Pathogenic variants in kinesin-related genes have been implicated in neurodevelopmental disorders and skeletal dysplasias. We identified de novo, heterozygous variants in KIF5B, encoding a kinesin-1 subunit, in four individuals with osteogenesis imperfecta. The variants cluster within the highly conserved kinesin motor domain and are predicted to interfere with nucleotide binding, although the mechanistic consequences on cell signaling and function are unknown.

METHODS: To understand the in vivo genetic mechanism of KIF5B variants, we modeled the p.Thr87Ile variant that was found in two patients in the C. elegans ortholog, …

Small Molecule Screen Identifies Pyrimethamine As An Inhibitor Of Nrf2-Driven Esophageal Hyperplasia, Chorlada Paiboonrungruang, Brittany Bowman, Julius Chembo, M Ben Major, Et Al.

2020-Current year OA Pubs

OBJECTIVE: NRF2 is a master transcription factor that regulates the stress response. NRF2 is frequently mutated and activated in human esophageal squamous cell carcinoma (ESCC), which drives resistance to chemotherapy and radiation therapy. Therefore, a great need exists for NRF2 inhibitors for targeted therapy of NRF2

DESIGN: We performed high-throughput screening of two compound libraries from which hit compounds were further validated in human ESCC cells and a genetically modified mouse model. The mechanism of action of one compound was explored by biochemical assays.

RESULTS: Using high-throughput screening of two small molecule compound libraries, we identified 11 hit compounds as …

An Automated Respiratory Data Pipeline For Waveform Characteristic Analysis, Savannah Lusk, Christopher S Ward, Andersen Chang, Avery Twitchell-Heyne, Shaun Fattig, Genevera Allen, Joanna L Jankowsky, Russell S Ray

Faculty, Staff and Students Publications

Comprehensive and accurate analysis of respiratory and metabolic data is crucial to modelling congenital, pathogenic and degenerative diseases converging on autonomic control failure. A lack of tools for high-throughput analysis of respiratory datasets remains a major challenge. We present Breathe Easy, a novel open-source pipeline for processing raw recordings and associated metadata into operative outcomes, publication-worthy graphs and robust statistical analyses including QQ and residual plots for assumption queries and data transformations. This pipeline uses a facile graphical user interface for uploading data files, setting waveform feature thresholds and defining experimental variables. Breathe Easy was validated against manual selection by …

Camkk2 As An Emerging Treatment Target For Bipolar Disorder, Jacqueline Kaiser, Kevin Nay, Christopher R Horne, Luke M Mcaloon, Oliver K Fuller, Abbey G Muller, Douglas G Whyte, Anthony R Means, Ken Walder, Michael Berk, Anthony J Hannan, James M Murphy, Mark A Febbraio, Andrew L Gundlach, John W Scott

Faculty, Staff and Students Publications

Current pharmacological treatments for bipolar disorder are inadequate and based on serendipitously discovered drugs often with limited efficacy, burdensome side-effects, and unclear mechanisms of action. Advances in drug development for the treatment of bipolar disorder remain incremental and have come largely from repurposing drugs used for other psychiatric conditions, a strategy that has failed to find truly revolutionary therapies, as it does not target the mood instability that characterises the condition. The lack of therapeutic innovation in the bipolar disorder field is largely due to a poor understanding of the underlying disease mechanisms and the consequent absence of validated drug …

P2y2 Purinergic Receptor Gene Deletion Protects Mice From Bacterial Endotoxin And Sepsis-Associated Liver Injury And Mortality, Athis R Arunachalam, Sanju S Samuel, Arunmani Mani, Janielle P Maynard, Kelsey M Stayer, Eric Dybbro, Subapradha Narayanan, Aalekhya Biswas, Saliha Pathan, Krishnakant Soni, Abu Hena Mostafa Kamal, Chandra Shekar R Ambati, Nagireddy Putluri, Moreshwar S Desai, Sundararajah Thevananther

Faculty, Staff and Students Publications

Prostate cancer (PCa) remains a leading cause of mortality among American men, with metastatic and recurrent disease posing significant therapeutic challenges due to a limited comprehension of the underlying biological processes governing disease initiation, dormancy, and progression. The conventional use of PCa cell lines has proven inadequate in elucidating the intricate molecular mechanisms driving PCa carcinogenesis, hindering the development of effective treatments. To address this gap, patient-derived primary cell cultures have been developed and play a pivotal role in unraveling the pathophysiological intricacies unique to PCa in each individual, offering valuable insights for translational research. This review explores the applications …

Targeted Inhibition Of Lncrna Malat1 Alters The Tumor Immune Microenvironment In Preclinical Syngeneic Mouse Models Of Triple-Negative Breast Cancer, Oluwatoyosi Adewunmi, Yichao Shen, Xiang H-F Zhang, Jeffrey M Rosen

Faculty, Staff and Students Publications

Long noncoding RNAs (lncRNA) play an important role in gene regulation in both normal tissues and cancer. Targeting lncRNAs is a promising therapeutic approach that has become feasible through the development of gapmer antisense oligonucleotides (ASO). Metastasis-associated lung adenocarcinoma transcript (Malat1) is an abundant lncRNA whose expression is upregulated in several cancers. Although Malat1 increases the migratory and invasive properties of tumor cells, its role in the tumor microenvironment (TME) is still not well defined. We explored the connection between Malat1 and the tumor immune microenvironment (TIME) using several immune-competent preclinical syngeneic Tp53-null triple-negative breast cancer (TNBC) mouse models that …

Dominant Negative Variants In Kif5b Cause Osteogenesis Imperfecta Via Down Regulation Of Mtor Signaling, Ronit Marom, Bo Zhang, Megan E Washington, I-Wen Song, Lindsay C Burrage, Vittoria C Rossi, Ava S Berrier, Anika Lindsey, Jacob Lesinski, Michael L Nonet, Jian Chen, Dustin Baldridge, Gary A Silverman, V Reid Sutton, Jill A Rosenfeld, Alyssa A Tran, M John Hicks, David R Murdock, Hongzheng Dai, Maryann Weis, Shalini N Jhangiani, Donna M Muzny, Richard A Gibbs, Richard Caswell, Carrie Pottinger, Deirdre Cilliers, Karen Stals, Undiagnosed Diseases Network, David Eyre, Deborah Krakow, Tim Schedl, Stephen C Pak, Brendan H Lee

Faculty, Staff and Students Publications

BACKGROUND: Kinesin motor proteins transport intracellular cargo, including mRNA, proteins, and organelles. Pathogenic variants in kinesin-related genes have been implicated in neurodevelopmental disorders and skeletal dysplasias. We identified de novo, heterozygous variants in KIF5B, encoding a kinesin-1 subunit, in four individuals with osteogenesis imperfecta. The variants cluster within the highly conserved kinesin motor domain and are predicted to interfere with nucleotide binding, although the mechanistic consequences on cell signaling and function are unknown.

METHODS: To understand the in vivo genetic mechanism of KIF5B variants, we modeled the p.Thr87Ile variant that was found in two patients in the C. elegans ortholog, …

P2y2 Purinergic Receptor Gene Deletion Protects Mice From Bacterial Endotoxin And Sepsis-Associated Liver Injury And Mortality, Athis R Arunachalam, Sanju S Samuel, Arunmani Mani, Janielle P Maynard, Kelsey M Stayer, Eric Dybbro, Subapradha Narayanan, Aalekhya Biswas, Saliha Pathan, Krishnakant Soni, Abu Hena Mostafa Kamal, Chandra Shekar R Ambati, Nagireddy Putluri, Moreshwar S Desai, Sundararajah Thevananther

Faculty, Staff and Students Publications

The liver plays a significant role in regulating a wide range of metabolic, homeostatic, and host-defense functions. However, the impact of liver injury on the host's ability to control bacteremia and morbidity in sepsis is not well understood. Leukocyte recruitment and activation lead to cytokine and chemokine release, which, in turn, trigger hepatocellular injury and elevate nucleotide levels in the extracellular milieu. P2Y2 purinergic receptors, G protein-coupled and activated by extracellular ATP/UTP, are expressed at the cell surface of hepatocytes and nonparenchymal cells. We sought to determine whether P2Y2 purinergic receptor function is necessary for the maladaptive host response to …

Cardiac Muscle-Restricted Partial Loss Of Nos1ap Expression Has Limited But Significant Impact On Electrocardiographic Features, Alexa Smith, Dallas Auer, Morgan Johnson, Ernesto Sanchez, Holly Ross, Christopher Ward, Aravinda Chakravarti, Ashish Kapoor

Faculty, Staff and Student Publications

Genome-wide association studies have identified sequence polymorphisms in a functional enhancer of the NOS1AP gene as the most common genetic regulator of QT interval and human cardiac NOS1AP gene expression in the general population. Functional studies based on in vitro overexpression in murine cardiomyocytes and ex vivo knockdown in zebrafish embryonic hearts, by us and others, have also demonstrated that NOS1AP expression levels can alter cellular electrophysiology. Here, to explore the role of NOS1AP in cardiac electrophysiology at an organismal level, we generated and characterized constitutive and heart muscle-restricted Nos1ap knockout mice to assess whether NOS1AP disruption alters the QT …

Aso Silencing Of A Glycosyltransferase, Poglut1, Improves The Liver Phenotypes In Mouse Models Of Alagille Syndrome, Nima Niknejad, Duncan Fox, Jennifer L Burwinkel, Neda Zarrin-Khameh, Soomin Cho, Armand Soriano, Ashley E Cast, Mario F Lopez, Kari A Huppert, Frank Rigo, Stacey S Huppert, Paymaan Jafar-Nejad, Hamed Jafar-Nejad

Faculty, Staff and Students Publications

BACKGROUND AND AIMS: Paucity of intrahepatic bile ducts (BDs) is caused by various etiologies and often leads to cholestatic liver disease. For example, in patients with Alagille syndrome (ALGS), which is a genetic disease primarily caused by mutations in jagged 1 ( JAG1) , BD paucity often results in severe cholestasis and liver damage. However, no mechanism-based therapy exists to restore the biliary system in ALGS or other diseases associated with BD paucity. Based on previous genetic observations, we investigated whether postnatal knockdown of the glycosyltransferase gene protein O -glucosyltransferase 1 ( Poglut1) can improve the ALGS liver phenotypes in …

Site-Specific Pathophysiology In A Neonatal Mouse Model Of Gastroparesis, Price T Edwards, Krishnakant G Soni, Margaret E Conner, Stephanie W Fowler, Jaime P P Foong, Rhian Stavely, Lily S Cheng, Geoffrey A Preidis

Faculty, Staff and Students Publications

BACKGROUND: Early-life events impact maturation of the gut microbiome, enteric nervous system, and gastrointestinal motility. We examined three regions of gastric tissue to determine how maternal separation and gut microbes influence the structure and motor function of specific regions of the neonatal mouse stomach.

METHODS: Germ-free and conventionally housed C57BL/6J mouse pups underwent timed maternal separation (TmSep) or nursed uninterrupted (controls) until 14 days of life. We assessed gastric emptying by quantifying the progression of gavaged fluorescein isothiocyanate (FITC)-dextran. With isolated rings of forestomach, corpus, and antrum, we measured tone and contractility by force transduction, gastric wall thickness by light …