Digital Commons Network^™

Spatial Transcriptomics Analysis Identifies A Tumor-Promoting Function Of The Meningeal Stroma In Melanoma Leptomeningeal Disease., Hasan Alhaddad, Oscar E. Ospina, Mariam Lotfy Khaled, Yuan Ren, Ethan Vallebuona, Mohammad Baraa Boozo, Peter A. Forsyth, Yolanda Pina, Robert Macaulay, Vincent Law, Kenneth Y. Tsai, W Douglas Cress, Brooke L. Fridley, Inna Smalley

Manuscripts, Articles, Book Chapters and Other Papers

Leptomeningeal disease (LMD) remains a rapidly lethal complication for late-stage melanoma patients. Here, we characterize the tumor microenvironment of LMD and patient-matched extra-cranial metastases using spatial transcriptomics in a small number of clinical specimens (nine tissues from two patients) with extensive in vitro and in vivo validation. The spatial landscape of melanoma LMD is characterized by a lack of immune infiltration and instead exhibits a higher level of stromal involvement. The tumor-stroma interactions at the leptomeninges activate tumor-promoting signaling, mediated through upregulation of SERPINA3. The meningeal stroma is required for melanoma cells to survive in the cerebrospinal fluid (CSF) and …

Targeting Mcl1-Driven Anti-Apoptotic Pathways Overcomes Blast Progression After Hypomethylating Agent Failure In Chronic Myelomonocytic Leukemia, Guillermo Montalban-Bravo, Natthakan Thongon, Juan Jose Rodriguez-Sevilla, Feiyang Ma, Irene Ganan-Gomez, Hui Yang, Yi June Kim, Vera Adema, Bethany Wildeman, Tomoyuki Tanaka, Faezeh Darbaniyan, Gheath Al-Atrash, Karen Dwyer, Sanam Loghavi, Rashmi Kanagal-Shamanna, Xingzhi Song, Jianhua Zhang, Koichi Takahashi, Hagop Kantarjian, Guillermo Garcia-Manero, Simona Colla

Faculty, Staff and Student Publications

RAS pathway mutations, which are present in 30% of patients with chronic myelomonocytic leukemia (CMML) at diagnosis, confer a high risk of resistance to and progression after hypomethylating agent (HMA) therapy, the current standard of care for the disease. Here, using single-cell, multi-omics technologies, we seek to dissect the biological mechanisms underlying the initiation and progression of RAS pathway-mutated CMML. We identify that RAS pathway mutations induce transcriptional reprogramming of hematopoietic stem and progenitor cells (HSPCs) and downstream monocytic populations in response to cell-intrinsic and -extrinsic inflammatory signaling that also impair the functions of immune cells. HSPCs expand at disease …

Neurogranin Modulates The Rate Of Association Between Calmodulin And Target Peptides, John A Putkey, Laurel Hoffman, Vladimir Berka, Xu Wang

Faculty, Staff and Student Publications

The best-known mode of action of calmodulin (CaM) is binding of Ca2+ to its N- and C-domains, followed by binding to target proteins. An underappreciated facet of this process is that CaM is typically bound to proteins at basal levels of free Ca2+, including the small, intrinsically disordered, neuronal IQ-motif proteins called PEP-19 and neurogranin (Ng). PEP-19 and Ng would not be effective competitive inhibitors of high-affinity Ca2+-dependent CaM targets at equilibrium because they bind to CaM with relatively low affinity, but they could influence the time course of CaM signaling by affecting the rate of association of CaM with …

Fate-Mapping And Functional Dissection Reveal Perilous Influence Of Type I Interferon Signaling In Mouse Brain Aging, Ethan R Roy, Sanming Li, Sepideh Saroukhani, Yanyu Wang, Wei Cao

Faculty, Staff and Student Publications

Background: Aging significantly elevates the risk of developing neurodegenerative diseases. Neuroinflammation is a universal hallmark of neurodegeneration as well as normal brain aging. Which branches of age-related neuroinflammation, and how they precondition the brain toward pathological progression, remain ill-understood. The presence of elevated type I interferon (IFN-I) has been documented in the aged brain, but its role in promoting degenerative processes, such as the loss of neurons in vulnerable regions, has not been studied in depth.

Methods: To comprehend the scope of IFN-I activity in the aging brain, we surveyed IFN-I-responsive reporter mice at multiple ages. We also examined 5- …

Protein Restriction Slows The Development And Progression Of Pathology In A Mouse Model Of Alzheimer's Disease, Reji Babygirija, Natalie M Niemi, Et Al.

2020-Current year OA Pubs

Dietary protein is a critical regulator of metabolic health and aging. Low protein diets are associated with healthy aging in humans, and dietary protein restriction extends the lifespan and healthspan of mice. In this study, we examined the effect of protein restriction (PR) on metabolic health and the development and progression of Alzheimer's disease (AD) in the 3xTg mouse model of AD. Here, we show that PR promotes leanness and glycemic control in 3xTg mice, specifically rescuing the glucose intolerance of 3xTg females. PR induces sex-specific alterations in circulating and brain metabolites, downregulating sphingolipid subclasses in 3xTg females. PR also …

Repeat Controlled Human Plasmodium Falciparum Infections Delay Bloodstream Patency And Reduce Symptoms, Patricia Ferrer, Andrea A Berry, Allison N Bucsan, Surendra K Prajapati, Karthik Krishnan, Michelle C Barbeau, David M Rickert, Sandra Mendoza Guerrero, Miho Usui, Yonas Abebe, Asha Patil, Sumana Chakravarty, Peter F Billingsley, Faith Pa'ahana-Brown, Kathy Strauss, Biraj Shrestha, Effie Nomicos, Gregory A Deye, B Kim Lee Sim, Stephen L Hoffman, Kim C Williamson, Kirsten E Lyke

Faculty, Staff and Student Publications

Resistance to clinical malaria takes years to develop even in hyperendemic regions and sterilizing immunity has rarely been observed. To evaluate the maturation of the host response against controlled repeat exposures to P. falciparum (Pf) NF54 strain-infected mosquitoes, we systematically monitored malaria-naïve participants through an initial exposure to uninfected mosquitoes and 4 subsequent homologous exposures to Pf-infected mosquitoes over 21 months (n = 8 males) (ClinicalTrials.gov# NCT03014258). The primary outcome was to determine whether protective immunity against parasite infection develops following repeat CHMI and the secondary outcomes were to track the clinical signs and symptoms of malaria and anti-Pf antibody …

Legend Of Merlin And The Quest For Cardiac Lineage Commitment, Rich Gang Li, James F Martin

Faculty, Staff and Students Publications

No abstract provided.

Remodeling Of Anti-Tumor Immunity With Antibodies Targeting A P53 Mutant, Dafei Chai, Junhao Wang, Chunmei Fan, Jing-Ming Lim, Xu Wang, Praveen Neeli, Xinfang Yu, Ken H Young, Yong Li

Faculty, Staff and Students Publications

BACKGROUND: p53, the most frequently mutated gene in cancer, lacks effective targeted drugs.

METHODS: We developed monoclonal antibodies (mAbs) that target a p53 hotspot mutation E285K without cross-reactivity with wild-type p53. They were delivered using lipid nanoparticles (LNPs) that encapsulate DNA plasmids. Western blot, BLI, flow cytometry, single-cell sequencing (scRNA-seq), and other methods were employed to assess the function of mAbs in vitro and in vivo.

RESULTS: These LNP-pE285K-mAbs in the IgG1 format exhibited a robust anti-tumor effect, facilitating the infiltration of immune cells, including CD8+ T, B, and NK cells. scRNA-seq revealed that IgG1 reduces immune inhibitory signaling, increases …

Short-Chain Fatty Acid Valerate Reduces Voluntary Alcohol Intake In Male Mice., Suresh C Bokoliya, Jordan Russell, Yair Dorsett, Hunter A Panier, Vijender Singh, Lauren Daddi, Hanshu Yuan, Liv R Dedon, Zhongmao Liu, Yuqi Zhou, Zefang Min, Jessica R Barson, Jonathan Covault, Jason A. Bubier, Yanjiao Zhou

Faculty Research 2024

BACKGROUND: Despite serious health and social consequences, effective intervention strategies for habitual alcohol binge drinking are lacking. The development of novel therapeutic and preventative approaches is highly desirable. Accumulating evidence in the past several years has established associations between the gut microbiome and microbial metabolites with drinking behavior, but druggable targets and their underlying mechanism of action are understudied.

RESULTS: Here, using a drink-in-the-dark mouse model, we identified a microbiome metabolite-based novel treatment (sodium valerate) that can reduce excessive alcohol drinking. Sodium valerate is a sodium salt of valeric acid short-chain fatty acid with a similar structure as γ-aminobutyric acid …

Sting Agonist 8803 Reprograms The Immune Microenvironment And Increases Survival In Preclinical Models Of Glioblastoma, Hinda Najem, Spencer T Lea, Shashwat Tripathi, Lisa Hurley, Chao-Hsien Chen, Ivana William, Moloud Sooreshjani, Michelle Bowie, Genevieve Hartley, Corey Dussold, Sebastian Pacheco, Crismita Dmello, Catalina Lee-Chang, Kathleen Mccortney, Alicia Steffens, Jordain Walshon, Martina Ott, Jun Wei, Anantha Marisetty, Irina Balyasnikova, Roger Stupp, Rimas V Lukas, Jian Hu, Charles David James, Craig M Horbinski, Maciej S Lesniak, David M Ashley, Waldemar Priebe, Leonidas C Platanias, Michael A Curran, Amy B Heimberger

Faculty, Staff and Student Publications

STING agonists can reprogram the tumor microenvironment to induce immunological clearance within the central nervous system. Using multiplexed sequential immunofluorescence (SeqIF) and the Ivy Glioblastoma Atlas, STING expression was found in myeloid populations and in the perivascular space. The STING agonist 8803 increased median survival in multiple preclinical models of glioblastoma, including QPP8, an immune checkpoint blockade-resistant model, where 100% of mice were cured. Ex vivo flow cytometry profiling during the therapeutic window demonstrated increases in myeloid tumor trafficking and activation, alongside enhancement of CD8+ T cell and NK effector responses. Treatment with 8803 reprogrammed microglia to express costimulatory CD80/CD86 …

Structural Characterization Of Ligand Binding And Ph-Specific Enzymatic Activity Of Mouse Acidic Mammalian Chitinase, Roberto Efraín Díaz, Andrew K Ecker, Galen J Correy, Pooja Asthana, Iris D Young, Bryan Faust, Michael C Thompson, Ian B Seiple, Steven Van Dyken, Richard M Locksley, James S Fraser

2020-Current year OA Pubs

Chitin is an abundant biopolymer and pathogen-associated molecular pattern that stimulates a host innate immune response. Mammals express chitin-binding and chitin-degrading proteins to remove chitin from the body. One of these proteins, Acidic Mammalian Chitinase (AMCase), is an enzyme known for its ability to function under acidic conditions in the stomach but is also active in tissues with more neutral pHs, such as the lung. Here, we used a combination of biochemical, structural, and computational modeling approaches to examine how the mouse homolog (mAMCase) can act in both acidic and neutral environments. We measured kinetic properties of mAMCase activity across …

Cancer-Associated Histone H3 N-Terminal Arginine Mutations Disrupt Prc2 Activity And Impair Differentiation, Benjamin A Nacev, Benjamin A Garcia, Et Al.

2020-Current year OA Pubs

Dysregulated epigenetic states are a hallmark of cancer and often arise from genetic alterations in epigenetic regulators. This includes missense mutations in histones, which, together with associated DNA, form nucleosome core particles. However, the oncogenic mechanisms of most histone mutations are unknown. Here, we demonstrate that cancer-associated histone mutations at arginines in the histone H3 N-terminal tail disrupt repressive chromatin domains, alter gene regulation, and dysregulate differentiation. We find that histone H3R2C and R26C mutants reduce transcriptionally repressive H3K27me3. While H3K27me3 depletion in cells expressing these mutants is exclusively observed on the minor fraction of histone tails harboring the mutations, …

Maldi Imaging Mass Spectrometry Visualizes The Distribution Of Antidepressant Duloxetine And Its Major Metabolites In Mouse Brain, Liver, Kidney, And Spleen Tissues, Saleh M Khalil, Xuan Qin, John M Hakenjos, Jian Wang, Zhaoyong Hu, Xinli Liu, Jin Wang, Mirjana Maletic-Savatic, Kevin R Mackenzie, Martin M Matzuk, Feng Li

Faculty, Staff and Student Publications

Imaging mass spectrometry (IMS) is a powerful tool for mapping the spatial distribution of unlabeled drugs and metabolites that may find application in assessing drug delivery, explaining drug efficacy, and identifying potential toxicity. This study focuses on determining the spatial distribution of the antidepressant duloxetine, which is widely prescribed despite common adverse effects (liver injury, constant headaches) whose mechanisms are not fully understood. We used high-resolution IMS with matrix-assisted laser desorption/ionization to examine the distribution of duloxetine and its major metabolites in four mouse organs where it may contribute to efficacy or toxicity: brain, liver, kidney, and spleen. In none …

The Ifitm5 Mutation In Osteogenesis Imperfecta Type V Is Associated With An Erk/Sox9-Dependent Osteoprogenitor Differentiation Defect, Ronit Marom, I-Wen Song, Emily C Busse, Megan E Washington, Ava S Berrier, Vittoria C Rossi, Laura Ortinau, Youngjae Jeong, Ming-Ming Jiang, Brian C Dawson, Mary Adeyeye, Carolina Leynes, Caressa D Lietman, Bridget M Stroup, Dominyka Batkovskyte, Mahim Jain, Yuqing Chen, Racel Cela, Alexis Castellon, Alyssa A Tran, Isabel Lorenzo, D Nicole Meyers, Shixia Huang, Alicia Turner, Vinitha Shenava, Maegen Wallace, Eric Orwoll, Dongsu Park, Catherine G Ambrose, Sandesh Cs Nagamani, Jason D Heaney, Brendan H Lee

Faculty, Staff and Students Publications

Osteogenesis imperfecta (OI) type V is the second most common form of OI, distinguished by hyperplastic callus formation and calcification of the interosseous membranes, in addition to the bone fragility. It is caused by a recurrent, dominant pathogenic variant (c.-14C>T) in interferon-induced transmembrane protein 5 (IFITM5). Here, we generated a conditional Rosa26-knockin mouse model to study the mechanistic consequences of the recurrent mutation. Expression of the mutant Ifitm5 in osteo-chondroprogenitor or chondrogenic cells resulted in low bone mass and growth retardation. Mutant limbs showed impaired endochondral ossification, cartilage overgrowth, and abnormal growth plate architecture. The cartilage phenotype correlates with …

A Longitudinal Mri And Tspo Pet-Based Investigation Of Brain Region-Specific Neuroprotection By Diazepam Versus Midazolam Following Organophosphate-Induced Seizures, Brad A Hobson, Douglas J Rowland, Yimeng Dou, Naomi Saito, Zachary T Harmany, Donald A Bruun, Danielle J Harvey, Abhijit J Chaudhari, Joel R Garbow, Pamela J Lein

2020-Current year OA Pubs

Acute poisoning with organophosphorus cholinesterase inhibitors (OPs), such as OP nerve agents and pesticides, can cause life threatening cholinergic crisis and status epilepticus (SE). Survivors often experience significant morbidity, including brain injury, acquired epilepsy, and cognitive deficits. Current medical countermeasures for acute OP poisoning include a benzodiazepine to mitigate seizures. Diazepam was long the benzodiazepine included in autoinjectors used to treat OP-induced seizures, but it is now being replaced in many guidelines by midazolam, which terminates seizures more quickly, particularly when administered intramuscularly. While a direct correlation between seizure duration and the extent of brain injury has been widely reported, …

Prevalence Of Anti-Myelin Oligodendrocyte Glycoprotein Antibodies Across Neuroinflammatory And Neurodegenerative Diseases, Ritu R Trivedi, Angela S Archambault, Clarice Pavlak, Matteo Gastaldi, Claudia Cantoni, Laura Ghezzi, Anne H Cross, Timothy M Miller, Gregory F Wu

2020-Current year OA Pubs

Inflammatory central nervous system (CNS) diseases, such as multiple sclerosis (MS) and myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD), are characterized by humoral immune abnormalities. Anti-MOG antibodies are not specific to MOGAD, with their presence described in MS. Autoantibodies may also be present and play a role in various neurodegenerative diseases. Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease driven by motor neuron dysfunction. While immune involvement in ALS has been recognized, the presence of antibodies targeting CNS myelin antigens has not been established. We aimed to establish a live cell-based assay for quantification of serum anti-MOG IgG1 in …

Summer Snow, Samuel L. Cooley

Ellipsis: A Journal of Art, Ideas, and Literature

No abstract provided.

Through The Cat-Map Gateway: A Brief History Of Cataract Genetics, Alan Shiels

2020-Current year OA Pubs

Clouding of the transparent eye lens, or cataract(s), is a leading cause of visual impairment that requires surgical replacement with a synthetic intraocular lens to effectively restore clear vision. Most frequently, cataract is acquired with aging as a multifactorial or complex trait. Cataract may also be inherited as a classic Mendelian trait-often with an early or pediatric onset-with or without other ocular and/or systemic features. Since the early 1990s, over 85 genes and loci have been genetically associated with inherited and/or age-related forms of cataract. While many of these underlying genes-including those for lens crystallins, connexins, and transcription factors-recapitulate signature …

Scanless Two-Photon Voltage Imaging, Ruth R Sims, Imane Bendifallah, Christiane Grimm, Aysha S Mohamed Lafirdeen, Soledad Domínguez, Chung Yuen Chan, Xiaoyu Lu, Benoît C Forget, François St-Pierre, Eirini Papagiakoumou, Valentina Emiliani

Faculty, Staff and Students Publications

Two-photon voltage imaging has long been heralded as a transformative approach capable of answering many long-standing questions in modern neuroscience. However, exploiting its full potential requires the development of novel imaging approaches well suited to the photophysical properties of genetically encoded voltage indicators. We demonstrate that parallel excitation approaches developed for scanless two-photon photostimulation enable high-SNR two-photon voltage imaging. We use whole-cell patch-clamp electrophysiology to perform a thorough characterization of scanless two-photon voltage imaging using three parallel illumination approaches and lasers with different repetition rates and wavelengths. We demonstrate voltage recordings of high-frequency spike trains and sub-threshold depolarizations from neurons …

Structural Analysis Of The Female Reptile Reproductive System By Micro-Computed Tomography And Optical Coherence Tomography†, Bonnie K Kircher, Michaela A Mccown, Deirdre M Scully, Richard R Behringer, Irina V Larina

Faculty, Staff and Student Publications

Volumetric data provide unprecedented structural insight to the reproductive tract and add vital anatomical context to the relationships between organs. The morphology of the female reproductive tract in non-avian reptiles varies between species, corresponding to a broad range of reproductive modes and providing valuable insight to comparative investigations of reproductive anatomy. However, reproductive studies in reptilian models, such as the brown anole studied here, have historically relied on histological methods to understand the anatomy. While these methods are highly effective for characterizing the cell types present in each organ, histological methods lose the 3D relationships between images and leave the …

Machine Learning In Time-Lapse Imaging To Differentiate Embryos From Young Vs Old Mice†, Liubin Yang, Carolina Leynes, Ashley Pawelka, Isabel Lorenzo, Andrew Chou, Brendan Lee, Jason D Heaney

Faculty, Staff and Students Publications

Time-lapse microscopy for embryos is a non-invasive technology used to characterize early embryo development. This study employs time-lapse microscopy and machine learning to elucidate changes in embryonic growth kinetics with maternal aging. We analyzed morphokinetic parameters of embryos from young and aged C57BL6/NJ mice via continuous imaging. Our findings show that aged embryos accelerated through cleavage stages (from 5-cells) to morula compared to younger counterparts, with no significant differences observed in later stages of blastulation. Unsupervised machine learning identified two distinct clusters comprising of embryos from aged or young donors. Moreover, in supervised learning, the extreme gradient boosting algorithm successfully …

An Inducible Genetic Tool To Track And Manipulate Specific Microglial States Reveals Their Plasticity And Roles In Remyelination, Kia M Barclay, Nora Abduljawad, Zuolin Cheng, Min Woo Kim, Lu Zhou, Jin Yang, Justin Rustenhoven, Jose A Mazzitelli, Leon C D Smyth, Dvita Kapadia, Simone Brioschi, Wandy Beatty, Jinchao Hou, Naresha Saligrama, Marco Colonna, Guoqiang Yu, Jonathan Kipnis, Qingyun Li

The Brown Foundation: Institute of Molecular Medicine

Recent single-cell RNA sequencing studies have revealed distinct microglial states in development and disease. These include proliferative region-associated microglia (PAM) in developing white matter and disease-associated microglia (DAM) prevalent in various neurodegenerative conditions. PAM and DAM share a similar core gene signature. However, the extent of the dynamism and plasticity of these microglial states, as well as their functional significance, remains elusive, partly due to the lack of specific tools. Here, we generated an inducible Cre driver line, Clec7a-CreERT2, that targets PAM and DAM in the brain parenchyma. Utilizing this tool, we profiled labeled cells during development and in several …

Slow Proliferation Of Bap1-Deficient Uveal Melanoma Cells Is Associated With Reduced S6 Signaling And Resistance To Nutrient Stress, Vivian Chua, Melisa Lopez-Anton, Mizue Terai, Ryota Tanaka, Usman Baqai, Timothy J Purwin, Jelan I Haj, Francis J Waltrich, Isabella Trachtenberg, Kristine Luo, Rohith Tudi, Angela Jeon, Anna Han, Inna Chervoneva, Michael A Davies, Julio A Aguirre-Ghiso, Takami Sato, Andrew E Aplin

Faculty, Staff and Student Publications

Uveal melanoma (UM) is the deadliest form of eye cancer in adults. Inactivating mutations and/or loss of expression of the gene encoding BRCA1-associated protein 1 (BAP1) in UM tumors are associated with an increased risk of metastasis. To investigate the mechanisms underlying this risk, we explored the functional consequences of BAP1 deficiency. UM cell lines expressing mutant BAP1 grew more slowly than those expressing wild-type BAP1 in culture and in vivo. The ability of BAP1 reconstitution to restore cell proliferation in BAP1-deficient cells required its deubiquitylase activity. Proteomic analysis showed that BAP1-deficient cells had decreased phosphorylation of ribosomal S6 and …

Tmprss2 Is A Tumor Suppressor And Its Downregulation Promotes Antitumor Immunity And Immunotherapy Response In Lung Adenocarcinoma, Zhixian Liu, Qiqi Lu, Zhilan Zhang, Qiushi Feng, Xiaosheng Wang

Faculty, Staff and Student Publications

Background: TMPRSS2, a key molecule for SARS-CoV-2 invading human host cells, has an association with cancer. However, its association with lung cancer remains insufficiently unexplored.

Methods: In five bulk transcriptomics datasets, one single-cell RNA sequencing (scRNA-seq) dataset and one proteomics dataset for lung adenocarcinoma (LUAD), we explored associations between TMPRSS2 expression and immune signatures, tumor progression phenotypes, genomic features, and clinical prognosis in LUAD by the bioinformatics approach. Furthermore, we performed experimental validation of the bioinformatics findings.

Results: TMPRSS2 expression levels correlated negatively with the enrichment levels of both immune-stimulatory and immune-inhibitory signatures, while they correlated positively with the ratios …

Role Of Ethanolamine Utilization And Bacterial Microcompartment Formation In Listeria Monocytogenes Intracellular Infection, Ayan Chatterjee, Karan Gautam Kaval, Danielle A Garsin

Faculty, Staff and Student Publications

Ethanolamine (EA) affects the colonization and pathogenicity of certain human bacterial pathogens in the gastrointestinal tract. However, EA can also affect the intracellular survival and replication of host cell invasive bacteria such as Listeria monocytogenes (LMO) and Salmonella enterica serovar Typhimurium (S. Typhimurium). The EA utilization (eut) genes can be categorized as regulatory, enzymatic, or structural, and previous work in LMO showed that loss of genes encoding functions for the enzymatic breakdown of EA inhibited LMO intracellular replication. In this work, we sought to further characterize the role of EA utilization during LMO infection of host …

Hemojuvelin-Mediated Hepcidin Induction Requires Both Bone Morphogenetic Protein Type I Receptors Alk2 And Alk3, Deniz Y Dogan, Eugen I Urzica, Isabelle Hornung, Philipp Kastl, David Oguama, Franca M Fette, Lien H Nguyen, Frank Rosenbauer, Kai Zacharowski, Ursula Klingmüller, Elise Gradhand, Andreas Von Knethen, Rüdiger Popp, Ingrid Fleming, Lisa Schrader, Andrea U Steinbicker

Faculty, Staff and Student Publications

Hemojuvelin (HJV) is a glycosylphosphatidylinositol-anchored protein of the repulsive guidance molecule family acting as a bone morphogenetic protein (BMP) coreceptor to induce the hepatic iron regulatory protein hepcidin. Hepcidin causes ubiquitination and degradation of the sole known iron exporter ferroportin, thereby limiting iron availability. The detailed signaling mechanism of HJV in vivo has yet to be investigated. In the current manuscript, we used an established model of adeno-associated virus (AAV)-mediated liver-specific overexpression of HJV in murine models of hepatocyte-specific deficiency of the BMP type I receptors Alk2 or Alk3. In control mice, HJV overexpression increased hepatic Hamp messenger RNA (mRNA) …

An Inducible Genetic Tool To Track And Manipulate Specific Microglial States Reveals Their Plasticity And Roles In Remyelination, Kia M Barclay, Nora Abduljawad, Min Woo Kim, Lu Zhou, Jin Yang, Justin Rustenhoven, Jose A Mazzitelli, Leon C D Smyth, Dvita Kapadia, Simone Brioschi, Wandy Beatty, Jinchao Hou, Naresha Saligrama, Marco Colonna, Jonathan Kipnis, Qingyun Li, Et Al.

2020-Current year OA Pubs

Recent single-cell RNA sequencing studies have revealed distinct microglial states in development and disease. These include proliferative-region-associated microglia (PAMs) in developing white matter and disease-associated microglia (DAMs) prevalent in various neurodegenerative conditions. PAMs and DAMs share a similar core gene signature. However, the extent of the dynamism and plasticity of these microglial states, as well as their functional significance, remains elusive, partly due to the lack of specific tools. Here, we generated an inducible Cre driver line, Clec7a-CreER

Limited Nerve Regeneration Across Acellular Nerve Allografts (Anas) Coincides With Changes In Blood Vessel Morphology And The Development Of A Pro-Inflammatory Microenvironment, Jesús A Acevedo Cintrón, Daniel A Hunter, Lauren Schellhardt, Deng Pan, Susan E Mackinnon, Matthew D Wood

2020-Current year OA Pubs

The use of acellular nerve allografts (ANAs) to reconstruct long nerve gaps (>3 cm) is associated with limited axon regeneration. To understand why ANA length might limit regeneration, we focused on identifying differences in the regenerative and vascular microenvironment that develop within ANAs based on their length. A rat sciatic nerve gap model was repaired with either short (2 cm) or long (4 cm) ANAs, and histomorphometry was used to measure myelinated axon regeneration and blood vessel morphology at various timepoints (2-, 4- and 8-weeks). Both groups demonstrated robust axonal regeneration within the proximal graft region, which continued across …

Frontotemporal Dementia-Like Disease Progression Elicited By Seeded Aggregation And Spread Of Fus, Sonia Vazquez-Sanchez, Britt Tilkin, Fatima Gasset-Rosa, Sitao Zhang, Diana Piol, Melissa Mcalonis-Downes, Jonathan Artates, Noe Govea-Perez, Yana Verresen, Lin Guo, Don Cleveland, James Shorter, Sandrine Da Cruz

Department of Biochemistry and Molecular Biology Faculty Papers

RNA binding proteins have emerged as central players in the mechanisms of many neurodegenerative diseases. In particular, a proteinopathy of fused in sarcoma (FUS) is present in some instances of familial Amyotrophic lateral sclerosis (ALS) and about 10% of sporadic Frontotemporal lobar degeneration (FTLD). Here we establish that focal injection of sonicated human FUS fibrils into brains of mice in which ALS-linked mutant or wild-type human FUS replaces endogenous mouse FUS is sufficient to induce focal cytoplasmic mislocalization and aggregation of mutant and wild-type FUS which with time spreads to distal regions of the brain. Human FUS fibril-induced FUS aggregation …

Tenovin-1, A Selective Sirt1/2 Inhibitor, Attenuates High-Fat Diet-Induced Hepatic Fibrosis Via Inhibition Of Hsc Activation In Zdf Rats, Swati Sharma, Sreevarsha Gali, Amit Kundu, Jae Hyeon Park, Jae-Sung Kim, Hyung Sik Kim

2020-Current year OA Pubs

Type 2 diabetes mellitus (T2DM) increases the risk of non-alcoholic fatty liver disease (NAFLD) progression to advanced stages, especially upon high-fat diet (HFD). HFD-induced hepatic fibrosis can be marked by oxidative stress, inflammation, and activation of hepatic stellate cells. Sirtuin 1/2 (SIRT1/2), NAD-dependent class III histone deacetylases, are involved in attenuation of fibrosis. In our conducted research, TGF-β1-activated LX-2 cells, free fatty acid (FFA)-treated simultaneous co-culture (SCC) cells, and HFD-induced hepatic fibrosis in Zucker diabetic fatty (ZDF) rats, a widely used animal model in the study of metabolic syndromes, were used to evaluate the protective effect of Tenovin-1, a SIRT1/2 …