Medicine and Health Sciences Commons^™

Functional Network Disorganization And Cognitive Decline Following Fractionated Whole-Brain Radiation In Mice, Benjamin A. Seitzman, Francisco J. Reynoso, Timothy J. Mitchell, Annie R. Bice, Anmol Jarang, Xiaodan Wang, Cedric Mpoy, Lori Strong, Buck E. Rogers, Carla M. Yuede, Joshua B. Rubin, Stephanie M. Perkins, Adam Q. Bauer

2020-Current year OA Pubs

Cognitive dysfunction following radiotherapy (RT) is one of the most common complications associated with RT delivered to the brain, but the precise mechanisms behind this dysfunction are not well understood, and to date, there are no preventative measures or effective treatments. To improve patient outcomes, a better understanding of the effects of radiation on the brain's functional systems is required. Functional magnetic resonance imaging (fMRI) has shown promise in this regard, however, compared to neural activity, hemodynamic measures of brain function are slow and indirect. Understanding how RT acutely and chronically affects functional brain organization requires more direct examination of …

Conditional Hepatocyte Ablation Of Pdia1 Uncovers Indispensable Roles In Both Apob And Mttp Folding To Support Vldl Secretion, Zhouji Chen, Shiyu Wang, Anita Pottekat, Alec Duffey, Insook Jang, Benny H Chang, Jaehyung Cho, Brian N Finck, Nicholas O Davidson, Randal J Kaufman

2020-Current year OA Pubs

OBJECTIVES: The assembly and secretion of hepatic very low-density lipoprotein (VLDL) plays pivotal roles in hepatic and plasma lipid homeostasis. Protein disulfide isomerase A1 (PDIA1/P4HB) is a molecular chaperone whose functions are essential for protein folding in the endoplasmic reticulum. Here we investigated the physiological requirement in vivo for PDIA1 in maintaining VLDL assembly and secretion.

METHODS: Pdia1/P4hb was conditionally deleted in adult mouse hepatocytes and the phenotypes characterized. Mechanistic analyses in primary hepatocytes determined how PDIA1 ablation alters MTTP synthesis and degradation as well as altering synthesis and secretion of Apolipoprotein B (APOB), along with complementary expression of intact …

Stem Cell Modeling Of Nervous System Tumors, Frank B Furnari, Corina Anastasaki, Shan Bian, Howard A Fine, Tomoyuki Koga, Lu Q Le, Fausto J Rodriguez, David H Gutmann

2020-Current year OA Pubs

Nervous system tumors, particularly brain tumors, represent the most common tumors in children and one of the most lethal tumors in adults. Despite decades of research, there are few effective therapies for these cancers. Although human nervous system tumor cells and genetically engineered mouse models have served as excellent platforms for drug discovery and preclinical testing, they have limitations with respect to accurately recapitulating important aspects of the pathobiology of spontaneously arising human tumors. For this reason, attention has turned to the deployment of human stem cell engineering involving human embryonic or induced pluripotent stem cells, in which genetic alterations …

Multiomic Profiling Reveals Metabolic Alterations Mediating Aberrant Platelet Activity And Inflammation In Myeloproliferative Neoplasms, Fan He, Angelo Ba Laranjeira, Tim Kong, Shuyang Lin, Katrina J. Ashworth, Alice Liu, Nina M. Lasky, Daniel Ac Fisher, Maggie J. Cox, Mary C. Fulbright, Lilian Antunes-Heck, Layow Yu, Molly Brakhane, Bei Gao, Stephen M. Sykes, Angelo D'Alessandro, Jorge Di Paola, Stephen T. Oh

2020-Current year OA Pubs

Platelets from patients with myeloproliferative neoplasms (MPNs) exhibit a hyperreactive phenotype. Here, we found elevated P-selectin exposure and platelet-leukocyte aggregates indicating activation of platelets from essential thrombocythemia (ET) patients. Single-cell RNA-seq analysis of primary samples revealed significant enrichment of transcripts related to platelet activation, mTOR, and oxidative phosphorylation in ET patient platelets. These observations were validated via proteomic profiling. Platelet metabolomics revealed distinct metabolic phenotypes consisting of elevated ATP generation accompanied by increases in the levels of multiple intermediates of the tricarboxylic acid cycle, but lower α-ketoglutarate (α-KG) in MPN patients. Inhibition of PI3K/AKT/mTOR signaling significantly reduced metabolic responses and …

Pycallingcards: An Integrated Environment For Visualizing, Analyzing, And Interpreting Calling Cards Data, Juanru Guo, Wenjin Zhang, Xuhua Chen, Allen Yen, Lucy Chen, Christian A Shively, Daofeng Li, Ting Wang, Joseph D Dougherty, Robi D Mitra

2020-Current year OA Pubs

MOTIVATION: Unraveling the transcriptional programs that control how cells divide, differentiate, and respond to their environments requires a precise understanding of transcription factors' (TFs) DNA-binding activities. Calling cards (CC) technology uses transposons to capture transient TF binding events at one instant in time and then read them out at a later time. This methodology can also be used to simultaneously measure TF binding and mRNA expression from single-cell CC and to record and integrate TF binding events across time in any cell type of interest without the need for purification. Despite these advantages, there has been a lack of dedicated …

Mousevuer: Video Based Open-Source System For Laboratory Mouse Home-Cage Monitoring, Ghadi Salem, Niall Cope, Marcial Garmendia, Alex Pu, Abhishek Somenhalli, Jonathan Krynitsky, Noah Cubert, Thomas Jones, George Dold, Anthony Fletcher, Alexxai Kravitz, Thomas Pohida, John Dennis

2020-Current year OA Pubs

Video monitoring of mice in the home-cage reveals behavior profiles without the disruptions caused by specialized test setups and makes it possible to quantify changes in behavior patterns continually over long time frames. Several commercial home-cage monitoring systems are available with varying costs and capabilities; however there are currently no open-source systems for home-cage monitoring. We present an open-source system for top-down video monitoring of research mice in a slightly modified home-cage. The system is designed for integration with Allentown NexGen ventilated racks and allows unobstructed view of up to three mice, but can also be operated outside the rack. …

Spatial And Amplitude Dynamics Of Neurostimulation: Insights From The Acute Intrahippocampal Kainate Seizure Mouse Model, Thomas J Foutz, Nicholas Rensing, Lirong Han, Dominique M Durand, Michael Wong

2020-Current year OA Pubs

OBJECTIVE: Neurostimulation is an emerging treatment for patients with drug-resistant epilepsy, which is used to suppress, prevent, and terminate seizure activity. Unfortunately, after implantation and despite best clinical practice, most patients continue to have persistent seizures even after years of empirical optimization. The objective of this study is to determine optimal spatial and amplitude properties of neurostimulation in inhibiting epileptiform activity in an acute hippocampal seizure model.

METHODS: We performed high-throughput testing of high-frequency focal brain stimulation in the acute intrahippocampal kainic acid mouse model of status epilepticus. We evaluated combinations of six anatomic targets and three stimulus amplitudes.

RESULTS: …

Safety, Immunogenicity, And Mechanism Of A Rotavirus Mrna-Lnp Vaccine In Mice, Chenxing Lu, Yan Li, Rong Chen, Xiaoqing Hu, Qingmei Leng, Xiaopeng Song, Xiaochen Lin, Jun Ye, Jinlan Wang, Jinmei Li, Lida Yao, Xianqiong Tang, Xiangjun Kuang, Guangming Zhang, Maosheng Sun, Yan Zhou, Hongjun Li

Faculty, Staff and Student Publications

Rotaviruses (RVs) are a major cause of diarrhea in young children worldwide. The currently available and licensed vaccines contain live attenuated RVs. Optimization of live attenuated RV vaccines or developing non-replicating RV (e.g., mRNA) vaccines is crucial for reducing the morbidity and mortality from RV infections. Herein, a nucleoside-modified mRNA vaccine encapsulated in lipid nanoparticles (LNP) and encoding the VP7 protein from the G1 type of RV was developed. The 5' untranslated region of an isolated human RV was utilized for the mRNA vaccine. After undergoing quality inspection, the VP7-mRNA vaccine was injected by subcutaneous or intramuscular routes into mice. …

The Mef2c Gene Dose-Dependently Controls Hippocampal Neurogenesis And The Expression Of Autism-Like Behaviors, Sreetama Basu, Eun Jeoung Ro, Zhi Liu, Hyunjung Kim, Aubrey Bennett, Seungwoo Kang, Hoonkyo Suh

The Brown Foundation: Institute of Molecular Medicine

Mutations in the activity-dependent transcription factor MEF2C have been associated with several neuropsychiatric disorders. Among these, autism spectrum disorder (ASD)-related behavioral deficits are manifested. Multiple animal models that harbor mutations in Mef2c have provided compelling evidence that Mef2c is indeed an ASD gene. However, studies in mice with germline or global brain knock-out of Mef2c are limited in their ability to identify the precise neural substrates and cell types that are required for the expression of Mef2c-mediated ASD behaviors. Given the role of hippocampal neurogenesis in cognitive and social behaviors, in this study we aimed to investigate the role …

Myd88 In Myofibroblasts Enhances Nonalcoholic Fatty Liver Disease-Related Hepatocarcinogenesis Via Promoting Macrophage M2 Polarization, Yu Liu, Haiqiang Chen, Xuanxuan Yan, Jie Zhang, Zhenzhong Deng, Maosheng Huang, Jianchun Gu, Jinhua Zhang

Faculty, Staff and Student Publications

Background: Nonalcoholic fatty liver disease (NAFLD) is a major cause of chronic liver diseases and has emerged as the leading factor in the pathogenesis of hepatocellular carcinoma (HCC). MyD88 contributes to the development of HCC. However, the underlying mechanism by which MyD88 in myofibroblasts regulates NAFLD-associated liver cancer development remains unknown.

Results: Myofibroblast MyD88-deficient (SMAMyD88-/-) mice were protected from diet-induced obesity and developed fewer and smaller liver tumors. MyD88 deficiency in myofibroblasts attenuated macrophage M2 polarization and fat accumulation in HCC tissues. Mechanistically, MyD88 signaling in myofibroblasts enhanced CCL9 secretion, thereby promoting macrophage M2 polarization. This process may depend on …

A Cataract-Causing Mutation In The Trpm3 Cation Channel Disrupts Calcium Dynamics In The Lens, Yuefang Zhou, Thomas M Bennett, Philip A Ruzycki, Zhaohua Guo, Yu-Qing Cao, Mohammad Shahidullah, Nicholas A Delamere, Alan Shiels

2020-Current year OA Pubs

TRPM3 belongs to the melastatin sub-family of transient receptor potential (TRPM) cation channels and has been shown to function as a steroid-activated, heat-sensitive calcium ion (Ca

Enhancing Antibody Responses By Multivalent Antigen Display On Thymus-Independent Dna Origami Scaffolds, Eike-Christian Wamhoff, James Brett Case, Shilpa Sanapala, Michael S Diamond, Et Al.

2020-Current year OA Pubs

Protein-based virus-like particles (P-VLPs) are commonly used to spatially organize antigens and enhance humoral immunity through multivalent antigen display. However, P-VLPs are thymus-dependent antigens that are themselves immunogenic and can induce B cell responses that may neutralize the platform. Here, we investigate thymus-independent DNA origami as an alternative material for multivalent antigen display using the receptor binding domain (RBD) of the SARS-CoV-2 spike protein, the primary target of neutralizing antibody responses. Sequential immunization of mice with DNA-based VLPs (DNA-VLPs) elicits protective neutralizing antibodies to SARS-CoV-2 in a manner that depends on the valency of the antigen displayed and on T …

Transmembrane Stem Factor Nanodiscs Enhanced Revascularization In A Hind Limb Ischemia Model In Diabetic, Hyperlipidemic Rabbits, Eri Takematsu, Miles Massidda, Gretchen Howe, Julia Goldman, Patricia Felli, Lei Mei, Gregory Callahan, Andrew D Sligar, Richard Smalling, Aaron B Baker

Faculty, Staff and Student Publications

Therapies to revascularize ischemic tissue have long been a goal for the treatment of vascular disease and other disorders. Therapies using stem cell factor (SCF), also known as a c-Kit ligand, had great promise for treating ischemia for myocardial infarct and stroke, however clinical development for SCF was stopped due to toxic side effects including mast cell activation in patients. We recently developed a novel therapy using a transmembrane form of SCF (tmSCF) delivered in lipid nanodiscs. In previous studies, we demonstrated tmSCF nanodiscs were able to induce revascularization of ischemia limbs in mice and did not activate mast cells. …

Single-Cell Multiomics Decodes Regulatory Programs For Mouse Secondary Palate Development, Fangfang Yan, Akiko Suzuki, Chihiro Iwaya, Guangsheng Pei, Xian Chen, Hiroki Yoshioka, Meifang Yu, Lukas M Simon, Junichi Iwata, Zhongming Zhao

Faculty, Staff and Student Publications

Perturbations in gene regulation during palatogenesis can lead to cleft palate, which is among the most common congenital birth defects. Here, we perform single-cell multiome sequencing and profile chromatin accessibility and gene expression simultaneously within the same cells (n = 36,154) isolated from mouse secondary palate across embryonic days (E) 12.5, E13.5, E14.0, and E14.5. We construct five trajectories representing continuous differentiation of cranial neural crest-derived multipotent cells into distinct lineages. By linking open chromatin signals to gene expression changes, we characterize the underlying lineage-determining transcription factors. In silico perturbation analysis identifies transcription factors SHOX2 and MEOX2 as important regulators …

Ubr5 Promotes Antiviral Immunity By Disengaging The Transcriptional Brake On Rig-I Like Receptors, Duomeng Yang, Tingting Geng, Andrew G Harrison, Jason G Cahoon, Jian Xing, Baihai Jiao, Mark Wang, Chao Cheng, Robert E Hill, Huadong Wang, Anthony T Vella, Gong Cheng, Yanlin Wang, Penghua Wang

Faculty, Staff and Students Publications

The Retinoic acid-Inducible Gene I (RIG-I) like receptors (RLRs) are the major viral RNA sensors essential for the initiation of antiviral immune responses. RLRs are subjected to stringent transcriptional and posttranslational regulations, of which ubiquitination is one of the most important. However, the role of ubiquitination in RLR transcription is unknown. Here, we screen 375 definite ubiquitin ligase knockout cell lines and identify Ubiquitin Protein Ligase E3 Component N-Recognin 5 (UBR5) as a positive regulator of RLR transcription. UBR5 deficiency reduces antiviral immune responses to RNA viruses, while increases viral replication in primary cells and mice. Ubr5 knockout mice are …

Association Of Genetic Variation In Col11a1 With Adolescent Idiopathic Scoliosis, Hao Yu, Lilian Antunes, Christina A Gurnett, Et Al.

2020-Current year OA Pubs

Adolescent idiopathic scoliosis (AIS) is a common and progressive spinal deformity in children that exhibits striking sexual dimorphism, with girls at more than fivefold greater risk of severe disease compared to boys. Despite its medical impact, the molecular mechanisms that drive AIS are largely unknown. We previously defined a female-specific AIS genetic risk locus in an enhancer near the

The Yap1/Taz-Tead Transcriptional Network Regulates Gene Expression At Neuromuscular Junctions In Skeletal Muscle Fibers, Lea Gessler, Danyil Huraskin, Yongzhi Jian, Nane Eiber, Zhaoyong Hu, Tomasz J Prószyński, Said Hashemolhosseini

Faculty, Staff and Students Publications

We examined YAP1/TAZ-TEAD signaling pathway activity at neuromuscular junctions (NMJs) of skeletal muscle fibers in adult mice. Our investigations revealed that muscle-specific knockouts of Yap1 or Taz, or both, demonstrate that these transcriptional coactivators regulate synaptic gene expression, the number and morphology of NMJs, and synaptic nuclei. Yap1 or Taz single knockout mice display reduced grip strength, fragmentation of NMJs, and accumulation of synaptic nuclei. Yap1/Taz muscle-specific double knockout mice do not survive beyond birth and possess almost no NMJs, the few detectable show severely impaired morphology and are organized in widened endplate bands; and with motor nerve endings being …

Hedgehog Activation Promotes Osteogenic Fates Of Growth Plate Resting Zone Chondrocytes Through Transient Clonal Competency, Shion Orikasa, Yuki Matsushita, Hiroaki Manabe, Michael Fogge, Zachary Lee, Koji Mizuhashi, Naoko Sakagami, Wanida Ono, Noriaki Ono

Faculty, Staff and Student Publications

The resting zone of the postnatal growth plate is organized by slow-cycling chondrocytes expressing parathyroid hormone-related protein (PTHrP), which include a subgroup of skeletal stem cells that contribute to the formation of columnar chondrocytes. The PTHrP-Indian hedgehog feedback regulation is essential for sustaining growth plate activities; however, molecular mechanisms regulating cell fates of PTHrP+ resting chondrocytes and their eventual transformation into osteoblasts remain largely undefined. Here, in a mouse model, we specifically activated Hedgehog signaling in PTHrP+ resting chondrocytes and traced the fate of their descendants using a tamoxifen-inducible Pthrp-creER line with patched-1-floxed and tdTomato reporter alleles. Hedgehog-activated PTHrP+ chondrocytes …

Intratumoral Biosynthesis Of Gold Nanoclusters By Pancreatic Cancer To Overcome Delivery Barriers To Radiosensitization, Aaron S Schwartz-Duval, Yuri Mackeyev, Iqbal Mahmud, Philip L Lorenzi, Mihai Gagea, Sunil Krishnan, Konstantin V Sokolov

Faculty, Staff and Student Publications

Nanoparticle delivery to solid tumors is a prime challenge in nanomedicine. Here, we approach this challenge through the lens of biogeochemistry, the field that studies the flow of chemical elements within ecosystems as manipulated by living cellular organisms and their environments. We leverage biogeochemistry concepts related to gold cycling against pancreatic cancer, considering mammalian organisms as drivers for gold nanoparticle biosynthesis. Sequestration of gold nanoparticles within tumors has been demonstrated as an effective strategy to enhance radiotherapy; however, the desmoplasia of pancreatic cancer impedes nanoparticle delivery. Our strategy overcomes this barrier by applying an atomic-scale agent, ionic gold, for intratumoral …

Non-Canonical Hedgehog Signaling Mediates Profibrotic Hematopoiesis-Stroma Crosstalk In Myeloproliferative Neoplasms, Jessica E Pritchard, Juliette E Pearce, Inge A M Snoeren, Stijn N R Fuchs, Katrin Götz, Fabian Peisker, Silke Wagner, Adam Benabid, Niklas Lutterbach, Vanessa Klöker, James S Nagai, Monica T Hannani, Anna K Galyga, Ellen Sistemich, Bella Banjanin, Niclas Flosdorf, Eric Bindels, Kathrin Olschok, Katharina Biaesch, Nicolas Chatain, Neha Bhagwat, Andrew Dunbar, Rita Sarkis, Olaia Naveiras, Marie-Luise Berres, Steffen Koschmieder, Ross L Levine, Ivan G Costa, Hélène F E Gleitz, Rafael Kramann, Rebekka K Schneider

Faculty, Staff and Student Publications

The role of hematopoietic Hedgehog signaling in myeloproliferative neoplasms (MPNs) remains incompletely understood despite data suggesting that Hedgehog (Hh) pathway inhibitors have therapeutic activity in patients. We aim to systematically interrogate the role of canonical vs. non-canonical Hh signaling in MPNs. We show that Gli1 protein levels in patient peripheral blood mononuclear cells (PBMCs) mark fibrotic progression and that, in murine MPN models, absence of hematopoietic Gli1, but not Gli2 or Smo, significantly reduces MPN phenotype and fibrosis, indicating that GLI1 in the MPN clone can be activated in a non-canonical fashion. Additionally, we establish that hematopoietic Gli1 has a …

Intratumoral Biosynthesis Of Gold Nanoclusters By Pancreatic Cancer To Overcome Delivery Barriers To Radiosensitization, Aaron S Schwartz-Duval, Yuri Mackeyev, Iqbal Mahmud, Philip L Lorenzi, Mihai Gagea, Sunil Krishnan, Konstantin V Sokolov

Faculty, Staff and Student Publications

Nanoparticle delivery to solid tumors is a prime challenge in nanomedicine. Here, we approach this challenge through the lens of biogeochemistry, the field that studies the flow of chemical elements within ecosystems as manipulated by living cellular organisms and their environments. We leverage biogeochemistry concepts related to gold cycling against pancreatic cancer, considering mammalian organisms as drivers for gold nanoparticle biosynthesis. Sequestration of gold nanoparticles within tumors has been demonstrated as an effective strategy to enhance radiotherapy; however, the desmoplasia of pancreatic cancer impedes nanoparticle delivery. Our strategy overcomes this barrier by applying an atomic-scale agent, ionic gold, for intratumoral …

Trex2 Deficiency Suppresses Spontaneous And Genotoxin-Associated Mutagenesis, Teresa Marple, Mi Young Son, Xiaodong Cheng, Jun Ho Ko, Patrick Sung, Paul Hasty

Faculty, Staff and Student Publications

TREX2, a 3'-5' exonuclease, is a part of the DNA damage tolerance (DDT) pathway that stabilizes replication forks (RFs) by ubiquitinating PCNA along with the ubiquitin E3 ligase RAD18 and other DDT factors. Mismatch repair (MMR) corrects DNA polymerase errors, including base mismatches and slippage. Here we demonstrate that TREX2 deletion reduces mutations in cells upon exposure to genotoxins, including those that cause base lesions and DNA polymerase slippage. Importantly, we show that TREX2 generates most of the spontaneous mutations in MMR-mutant cells derived from mice and people. TREX2-induced mutagenesis is dependent on the nuclease and DNA-binding attributes of TREX2. …

Neuronal Deletion Of The Circadian Clock Gene Bmal1 Induces Cell-Autonomous Dopaminergic Neurodegeneration, Michael K. Kanan, Patrick W. Sheehan, Jessica N. Haines, Pedro G. Gomez, Adya Dhuler, Collin J. Nadarajah, Zachary M. Wargel, Brittany M. Freeberg, Hemanth R. Nelvagal, Mariko Izumo, Joseph S. Takahashi, Jonathan D. Cooper, Albert A. Davis, Erik S. Musiek

2020-Current year OA Pubs

Circadian rhythm dysfunction is a hallmark of Parkinson disease (PD), and diminished expression of the core clock gene Bmal1 has been described in patients with PD. BMAL1 is required for core circadian clock function but also serves nonrhythmic functions. Germline Bmal1 deletion can cause brain oxidative stress and synapse loss in mice, and it can exacerbate dopaminergic neurodegeneration in response to the toxin MPTP. Here we examined the effect of cell type-specific Bmal1 deletion on dopaminergic neuron viability in vivo. We observed that global, postnatal deletion of Bmal1 caused spontaneous loss of tyrosine hydroxylase+ (TH+) dopaminergic neurons in the substantia …

An Orally Available Compound Suppresses Glucagon Hypersecretion And Normalizes Hyperglycemia In Type 1 Diabetes, Farzad Asadi, Subhadra C. Gunawardana, Roland E. Dolle, David W. Piston

2020-Current year OA Pubs

Suppression of glucagon hypersecretion can normalize hyperglycemia during type 1 diabetes (T1D). Activating erythropoietin-producing human hepatocellular receptor type-A4 (EphA4) on α cells reduced glucagon hypersecretion from dispersed α cells and T1D islets from both human donor and mouse models. We synthesized a high-affinity small molecule agonist for the EphA4 receptor, WCDD301, which showed robust plasma and liver microsome metabolic stability in both mouse and human preparations. In islets and dispersed islet cells from nondiabetic and T1D human donors, WCDD301 reduced glucagon secretion comparable to the natural EphA4 ligand, Ephrin-A5. In diabetic NOD and streptozotocin-treated mice, once-daily oral administration of WCDD301 …

Cpsa Mediates Infection Of Recruited Lung Myeloid Cells By Mycobacterium Tuberculosis, Steven J Grigsby, G V R Krishna Prasad, Joshua B Wallach, Ekansh Mittal, Fong-Fu Hsu, Dirk Schnappinger, Jennifer A Philips

2020-Current year OA Pubs

Mycobacterium tuberculosis (Mtb) possesses an arsenal of virulence factors to evade host immunity. Previously, we showed that the Mtb protein CpsA, which protects Mtb against the host NADPH oxidase, is required in mice during the first 3 weeks of infection but is thereafter dispensable for full virulence. Using flow cytometry, we find that ΔcpsA Mtb is retained in alveolar macrophages, impaired in recruiting and disseminating into monocyte-derived cells, and more likely to be localized in airway cells than wild-type Mtb. The lungs of ΔcpsA-infected mice also have markedly fewer antigen-specific T cells, indicating a delay in adaptive immunity. Thus, we …

A New Perspective On Intervertebral Disc Calcification-From Bench To Bedside, Emanuel Novais, Rajkishen Narayanan, Jose Canseco, Koen Van De Wetering, Christopher Kepler, Alan Hilibrand, Alex Vaccaro, Makarand Risbud

Department of Orthopaedic Surgery Faculty Papers

Disc degeneration primarily contributes to chronic low back and neck pain. Consequently, there is an urgent need to understand the spectrum of disc degeneration phenotypes such as fibrosis, ectopic calcification, herniation, or mixed phenotypes. Amongst these phenotypes, disc calcification is the least studied. Ectopic calcification, by definition, is the pathological mineralization of soft tissues, widely studied in the context of conditions that afflict vasculature, skin, and cartilage. Clinically, disc calcification is associated with poor surgical outcomes and back pain refractory to conservative treatment. It is frequently seen as a consequence of disc aging and progressive degeneration but exhibits unique molecular …

Microglia-Derived Exosomes Modulate Myelin Regeneration Via Mir-615-5p/Myrf Axis, Xiao-Yu Ji, Yu-Xin Guo, Li-Bin Wang, Wen-Cheng Wu, Jia-Qi Wang, Jin He, Rui Gao, Javad Rasouli, Meng-Yuan Gao, Zhen-Hai Wang, Dan Xiao, Wei-Feng Zhang, Bogoljub Ciric, Yuan Zhang, Xing Li

Department of Neurology Faculty Papers

Demyelination and failure of remyelination in the central nervous system (CNS) characterize a number of neurological disorders. Spontaneous remyelination in demyelinating diseases is limited, as oligodendrocyte precursor cells (OPCs), which are often present in demyelinated lesions in abundance, mostly fail to differentiate into oligodendrocytes, the myelinating cells in the CNS. In addition to OPCs, the lesions are assembled numbers of activated resident microglia/infiltrated macrophages; however, the mechanisms and potential role of interactions between the microglia/macrophages and OPCs are poorly understood. Here, we generated a transcriptional profile of exosomes from activated microglia, and found that miR-615-5p was elevated. miR-615-5p bound to …

Dietary Folate And Cofactors Accelerate Age-Dependent P16 Epimutation To Promote Intestinal Tumorigenesis, Li Yang, Robert C Peery, Leah M Farmer, Xia Gao, Yiqun Zhang, Chad J Creighton, Lanjing Zhang, Lanlan Shen

Faculty, Staff and Students Publications

The extent to which non-genetic environmental factors, such as diet, contribute to carcinogenesis has been long debated. One potential mechanism for the effects of environmental factors is through epigenetic modifications that affect gene expression without changing the underlying DNA sequence. However, the functional cooperation between dietary factors and cancer-causing epigenetic regulation is largely unknown. Here, we use a mouse model of age-dependent p16 epimutation, in which the p16 gene activity is directly controlled by promoter DNA methylation. We show p16 epimutation is modulated by folate and cofactors in dietary supplementation, which leads to increased colon cancer risk. Importantly, our findings …

Acetylcholine Receptor Based Chemogenetics Engineered For Neuronal Inhibition And Seizure Control Assessed In Mice, Quynh-Anh Nguyen, Peter M Klein, Cheng Xie, Katelyn N Benthall, Jillian Iafrati, Jesslyn Homidan, Jacob T Bendor, Barna Dudok, Jordan S Farrell, Tilo Gschwind, Charlotte L Porter, Annahita Keravala, G Steven Dodson, Ivan Soltesz

Faculty, Staff and Students Publications

Epilepsy is a prevalent disorder involving neuronal network hyperexcitability, yet existing therapeutic strategies often fail to provide optimal patient outcomes. Chemogenetic approaches, where exogenous receptors are expressed in defined brain areas and specifically activated by selective agonists, are appealing methods to constrain overactive neuronal activity. We developed BARNI (Bradanicline- and Acetylcholine-activated Receptor for Neuronal Inhibition), an engineered channel comprised of the α7 nicotinic acetylcholine receptor ligand-binding domain coupled to an α1 glycine receptor anion pore domain. Here we demonstrate that BARNI activation by the clinical stage α7 nicotinic acetylcholine receptor-selective agonist bradanicline effectively suppressed targeted neuronal activity, and controlled both …

Cdk4/6 Inhibition Sensitizes Intracranial Tumors To Pd-1 Blockade In Preclinical Models Of Brain Metastasis, Naema Nayyar, Magali A De Sauvage, Jane Chuprin, Emily M Sullivan, Mohini Singh, Consuelo Torrini, Britney S Zhang, Sushobhana Bandyopadhyay, Keith A Daniels, Christopher Alvarez-Breckenridge, Ashish Dahal, Michael A Brehm, Priscilla K Brastianos

Faculty, Staff and Student Publications

PURPOSE: Brain metastases are associated with high morbidity and are often resistant to immune checkpoint inhibitors. We evaluated whether CDK4/6 inhibitor (CDKi) abemaciclib can sensitize intracranial tumors to programmed cell death protein 1 (PD-1) inhibition in mouse models of melanoma and breast cancer brain metastasis.

EXPERIMENTAL DESIGN: Treatment response was evaluated in vivo using immunocompetent mouse models of brain metastasis bearing concurrent intracranial and extracranial tumors. Treatment effect on intracranial and extracranial tumor-immune microenvironments (TIME) was evaluated using immunofluorescence, multiplex immunoassays, high-parameter flow cytometry, and T-cell receptor profiling. Mice with humanized immune systems were evaluated using flow cytometry to study …