Neurology Commons^™

A Crosstalk Between Gut And Brain In Sepsis-Induced Cognitive Decline\, Vijayasree V Giridharan, Jaqueline S Generoso, Leonardo Lence, Gabriela Candiotto, Emílio Streck, Fabricia Petronilho, Anilkumar Pillai, Tarek Sharshar, Felipe Dal-Pizzol, Tatiana Barichello

Faculty, Staff and Student Publications

BACKGROUND: Sepsis is a potentially fatal disease characterized by acute organ failure that affects more than 30 million people worldwide. Inflammation is strongly associated with sepsis, and patients can experience impairments in memory, concentration, verbal fluency, and executive functioning after being discharged from the hospital. We hypothesize that sepsis disrupts the microbiota-gut-brain axis homeostasis triggering cognitive impairment. This immune activation persists during treatment, causing neurological dysfunction in sepsis survivors.

METHODS: To test our hypothesis, adult Wistar rats were subjected to cecal-ligation and perforation (CLP) or sham (non-CLP) surgeries. The animals were subjected to the [

RESULTS: Compared to the control …

A Weakened Recurrent Circuit In The Hippocampus Of Rett Syndrome Mice Disrupts Long-Term Memory Representations, Lingjie He, Matthew S Caudill, Junzhan Jing, Wei Wang, Yaling Sun, Jianrong Tang, Xiaolong Jiang, Huda Y Zoghbi

Duncan NRI Faculty and Staff Publications

Successful recall of a contextual memory requires reactivating ensembles of hippocampal cells that were allocated during memory formation. Altering the ratio of excitation-to-inhibition (E/I) during memory retrieval can bias cell participation in an ensemble and hinder memory recall. In the case of Rett syndrome (RTT), a neurological disorder with severe learning and memory deficits, the E/I balance is altered, but the source of this imbalance is unknown. Using in vivo imaging during an associative memory task, we show that during long-term memory retrieval, RTT CA1 cells poorly distinguish mnemonic context and form larger ensembles than wild-type mouse cells. Simultaneous multiple …

Biliverdin Reductase Bridges Focal Adhesion Kinase To Src To Modulate Synaptic Signaling, Chirag Vasavda, Evan R Semenza, Jason Liew, Ruchita Kothari, Ryan S Dhindsa, Shruthi Shanmukha, Anthony Lin, Robert Tokhunts, Cristina Ricco, Adele M Snowman, Lauren Albacarys, Francesco Pastore, Cristian Ripoli, Claudio Grassi, Eugenio Barone, Michael D Kornberg, Xinzhong Dong, Bindu D Paul, Solomon H Snyder

Duncan NRI Faculty and Staff Publications

Synapses connect discrete neurons into vast networks that send, receive, and encode diverse forms of information. Synaptic function and plasticity—the neuronal process of adapting to diverse and variable inputs—depend on the dynamic nature of synaptic molecular components, which is mediated in part by cell adhesion signaling pathways. Here, we found that the enzyme biliverdin reductase (BVR) physically links together key focal adhesion signaling molecules at the synapse. BVR-null (BVR−/−) mice exhibited substantial deficits in learning and memory on neurocognitive tests, and hippocampal slices in which BVR was postsynaptically depleted showed deficits in electrophysiological responses to stimuli. …

Characterization Of Retinal Function And Structure In The Mptp Murine Model Of Parkinson's Diseasecharacterization Of Retinal Function And Structure In The Mptp Murine Model Of Parkinson’S Disease, Katie K N Tran, Vickie H Y Wong, Jeremiah K H Lim, Ali Shahandeh, Anh Hoang, David I Finkelstein, Bang V Bui, Christine T O Nguyen

Faculty, Staff and Student Publications

In addition to well characterized motor symptoms, visual disturbances are increasingly recognized as an early manifestation in Parkinson's disease (PD). A better understanding of the mechanisms underlying these changes would facilitate the development of vision tests which can be used as preclinical biomarkers to support the development of novel therapeutics for PD. This study aims to characterize the retinal phenotype of a mouse model of dopaminergic dysfunction and to examine whether these changes are reversible with levodopa treatment. We use a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD to characterize the neurotoxic effects of MPTP on in vivo retinal function (electroretinography, …

Cross-Species Genetic Screens Identify Transglutaminase 5 As A Regulator Of Polyglutamine-Expanded Ataxin-1, Won-Seok Lee, Ismael Al-Ramahi, Hyun-Hwan Jeong, Youjin Jang, Tao Lin, Carolyn J Adamski, Laura A Lavery, Smruti Rath, Ronald Richman, Vitaliy V Bondar, Elizabeth Alcala, Jean-Pierre Revelli, Harry T Orr, Zhandong Liu, Juan Botas, Huda Y Zoghbi

Duncan NRI Faculty and Staff Publications

Many neurodegenerative disorders are caused by abnormal accumulation of misfolded proteins. In spinocerebellar ataxia type 1 (SCA1), accumulation of polyglutamine-expanded (polyQ-expanded) ataxin-1 (ATXN1) causes neuronal toxicity. Lowering total ATXN1, especially the polyQ-expanded form, alleviates disease phenotypes in mice, but the molecular mechanism by which the mutant ATXN1 is specifically modulated is not understood. Here, we identified 22 mutant ATXN1 regulators by performing a cross-species screen of 7787 and 2144 genes in human cells and Drosophila eyes, respectively. Among them, transglutaminase 5 (TG5) preferentially regulated mutant ATXN1 over the WT protein. TG enzymes catalyzed cross-linking of ATXN1 in a polyQ-length–dependent manner, …

Reduction Of Mutant Atxn1 Rescues Premature Death In A Conditional Sca1 Mouse Model, James P Orengo, Larissa Nitschke, Meike E Van Der Heijden, Nicholas A Ciaburri, Harry T Orr, Huda Y Zoghbi

Duncan NRI Faculty and Staff Publications

Spinocerebellar ataxia type 1 (SCA1) is an adult-onset neurodegenerative disorder. As disease progresses, motor neurons are affected, and their dysfunction contributes toward the inability to maintain proper respiratory function, a major driving force for premature death in SCA1. To investigate the isolated role of motor neurons in SCA1, we created a conditional SCA1 (cSCA1) mouse model. This model suppresses expression of the pathogenic SCA1 allele with a floxed stop cassette. cSCA1 mice crossed to a ubiquitous Cre line recapitulate all the major features of the original SCA1 mouse model; however, they took twice as long to develop. We found that …

Dynamics Of Huntingtin Protein Interactions In The Striatum Identifies Candidate Modifiers Of Huntington Disease, Todd M Greco, Christopher Secker, Eduardo Silva Ramos, Joel D Federspiel, Jeh-Ping Liu, Alma M Perez, Ismael Al-Ramahi, Jeffrey P Cantle, Jeffrey B Carroll, Juan Botas, Scott O Zeitlin, Erich E Wanker, Ileana M Cristea

Duncan NRI Faculty and Staff Publications

Huntington’s disease (HD) is a monogenic neurodegenerative disorder with one causative gene, huntingtin (HTT). Yet, HD pathobiology is multifactorial, suggesting that cellular factors influence disease progression. Here, we define HTT protein-protein interactions (PPIs) perturbed by the mutant protein with expanded polyglutamine in the mouse striatum, a brain region with selective HD vulnerability. Using metabolically labeled tissues and immunoaffinity purification-mass spectrometry, we establish that polyglutamine-dependent modulation of HTT PPI abundances and relative stability starts at an early stage of pathogenesis in a Q140 HD mouse model. We identify direct and indirect PPIs that are also genetic disease modifiers using in-cell two-hybrid …

Loss-Of-Function Variants In Tiam1 Are Associated With Developmental Delay, Intellectual Disability, And Seizures, Shenzhao Lu, Rebecca Hernan, Paul C Marcogliese, Yan Huang, Tracy S Gertler, Meltem Akcaboy, Shiyong Liu, Hyung-Lok Chung, Xueyang Pan, Xiaoqin Sun, Melahat Melek Oguz, Ulkühan Oztoprak, Jeroen H F De Baaij, Jelena Ivanisevic, Erin Mcginnis, Maria J Guillen Sacoto, Wendy K Chung, Hugo J Bellen

Duncan NRI Faculty and Staff Publications

TIAM Rac1-associated GEF 1 (TIAM1) regulates RAC1 signaling pathways that affect the control of neuronal morphogenesis and neurite outgrowth by modulating the actin cytoskeletal network. To date, TIAM1 has not been associated with a Mendelian disorder. Here, we describe five individuals with bi-allelic TIAM1 missense variants who have developmental delay, intellectual disability, speech delay, and seizures. Bioinformatic analyses demonstrate that these variants are rare and likely pathogenic. We found that the Drosophila ortholog of TIAM1, still life (sif), is expressed in larval and adult central nervous system (CNS) and is mainly expressed in a subset of neurons, but not in …

Disrupting The Myc-Tfeb Circuit Impairs Amino Acid Homeostasis And Provokes Metabolic Anergy, Mario R Fernandez, Franz X Schaub, Chunying Yang, Weimin Li, Seongseok Yun, Stephanie K Schaub, Frank C Dorsey, Min Liu, Meredith A Steeves, Andrea Ballabio, Alexandar Tzankov, Zhihua Chen, John M Koomen, Anders E Berglund, John L Cleveland

Duncan NRI Faculty and Staff Publications

MYC family oncoproteins are regulators of metabolic reprogramming that sustains cancer cell anabolism. Normal cells adapt to nutrient-limiting conditions by activating autophagy, which is required for amino acid (AA) homeostasis. Here we report that the autophagy pathway is suppressed by Myc in normal B cells, in premalignant and neoplastic B cells of Eμ-Myc transgenic mice, and in human MYC-driven Burkitt lymphoma. Myc suppresses autophagy by antagonizing the expression and function of transcription factor EB (TFEB), a master regulator of autophagy. Mechanisms that sustained AA pools in MYC-expressing B cells include coordinated induction of the proteasome and increases in AA …

Drosophila Functional Screening Of De Novo Variants In Autism Uncovers Damaging Variants And Facilitates Discovery Of Rare Neurodevelopmental Diseases, Paul C Marcogliese, Samantha L Deal, Jonathan Andrews, J Michael Harnish, V Hemanjani Bhavana, Hillary K Graves, Sharayu Jangam, Xi Luo, Ning Liu, Danqing Bei, Yu-Hsin Chao, Brooke Hull, Pei-Tseng Lee, Hongling Pan, Pradnya Bhadane, Mei-Chu Huang, Colleen M Longley, Hsiao-Tuan Chao, Hyung-Lok Chung, Nele A Haelterman, Oguz Kanca, Sathiya N Manivannan, Linda Z Rossetti, Ryan J German, Amanda Gerard, Eva Maria Christina Schwaibold, Sarah Fehr, Renzo Guerrini, Annalisa Vetro, Eleina England, Chaya N Murali, Tahsin Stefan Barakat, Marieke F Van Dooren, Martina Wilke, Marjon Van Slegtenhorst, Gaetan Lesca, Isabelle Sabatier, Nicolas Chatron, Catherine A Brownstein, Jill A Madden, Pankaj B Agrawal, Boris Keren, Thomas Courtin, Laurence Perrin, Melanie Brugger, Timo Roser, Steffen Leiz, Frederic Tran Mau-Them, Julian Delanne, Elena Sukarova-Angelovska, Slavica Trajkova, Erik Rosenhahn, Vincent Strehlow, Konrad Platzer, Roberto Keller, Lisa Pavinato, Alfredo Brusco, Jill A Rosenfeld, Ronit Marom, Michael F Wangler, Shinya Yamamoto

Duncan NRI Faculty and Staff Publications

Individuals with autism spectrum disorder (ASD) exhibit an increased burden of de novo mutations (DNMs) in a broadening range of genes. While these studies have implicated hundreds of genes in ASD pathogenesis, which DNMs cause functional consequences in vivo remains unclear. We functionally test the effects of ASD missense DNMs using Drosophila through "humanization" rescue and overexpression-based strategies. We examine 79 ASD variants in 74 genes identified in the Simons Simplex Collection and find 38% of them to cause functional alterations. Moreover, we identify GLRA2 as the cause of a spectrum of neurodevelopmental phenotypes beyond ASD in 13 previously undiagnosed …

Fly Cell Atlas: A Single-Nucleus Transcriptomic Atlas Of The Adult Fruit Fly, Hongjie Li, Jasper Janssens, Maxime De Waegeneer, Sai Saroja Kolluru, Kristofer Davie, Vincent Gardeux, Wouter Saelens, Fabrice P A David, Maria Brbić, Katina Spanier, Jure Leskovec, Colleen N Mclaughlin, Qijing Xie, Robert C Jones, Katja Brueckner, Jiwon Shim, Sudhir Gopal Tattikota, Frank Schnorrer, Katja Rust, Todd G Nystul, Zita Carvalho-Santos, Carlos Ribeiro, Soumitra Pal, Sharvani Mahadevaraju, Teresa M Przytycka, Aaron M Allen, Stephen F Goodwin, Cameron W Berry, Margaret T Fuller, Helen White-Cooper, Erika L Matunis, Stephen Dinardo, Anthony Galenza, Lucy Erin O'Brien, Julian A T Dow, Fca Consortium, Heinrich Jasper, Brian Oliver, Norbert Perrimon, Bart Deplancke, Stephen R Quake, Liqun Luo, Stein Aerts, Devika Agarwal, Yasir Ahmed-Braimah, Michelle Arbeitman, Majd M Ariss, Jordan Augsburger, Kumar Ayush, Catherine C Baker, Torsten Banisch, Katja Birker, Rolf Bodmer, Benjamin Bolival, Susanna E Brantley, Julie A Brill, Nora C Brown, Norene A Buehner, Xiaoyu Tracy Cai, Rita Cardoso-Figueiredo, Fernando Casares, Amy Chang, Thomas R Clandinin, Sheela Crasta, Claude Desplan, Angela M Detweiler, Darshan B Dhakan, Erika Donà, Stefanie Engert, Swann Floc'hlay, Nancy George, Amanda J González-Segarra, Andrew K Groves, Samantha Gumbin, Yanmeng Guo, Devon E Harris, Yael Heifetz, Stephen L Holtz, Felix Horns, Bruno Hudry, Ruei-Jiun Hung, Yuh Nung Jan, Jacob S Jaszczak, Gregory S X E Jefferis, Jim Karkanias, Timothy L Karr, Nadja Sandra Katheder, James Kezos, Anna A Kim, Seung K Kim, Lutz Kockel, Nikolaos Konstantinides, Thomas B Kornberg, Henry M Krause, Andrew Thomas Labott, Meghan Laturney, Ruth Lehmann, Sarah Leinwand, Jiefu Li, Joshua Shing Shun Li, Kai Li, Ke Li, Liying Li, Tun Li, Maria Litovchenko, Han-Hsuan Liu, Yifang Liu, Tzu-Chiao Lu, Jonathan Manning, Anjeli Mase, Mikaela Matera-Vatnick, Neuza Reis Matias, Caitlin E Mcdonough-Goldstein, Aaron Mcgeever, Alex D Mclachlan, Paola Moreno-Roman, Norma Neff, Megan Neville, Sang Ngo, Tanja Nielsen, Caitlin E O'Brien, David Osumi-Sutherland, Mehmet Neset Özel, Irene Papatheodorou, Maja Petkovic, Clare Pilgrim, Angela Oliveira Pisco, Carolina Reisenman, Erin Nicole Sanders, Gilberto Dos Santos, Kristin Scott, Aparna Sherlekar, Philip Shiu, David Sims, Rene V Sit, Maija Slaidina, Harold E Smith, Gabriella Sterne, Yu-Han Su, Daniel Sutton, Marco Tamayo, Michelle Tan, Ibrahim Tastekin, Christoph Treiber, David Vacek, Georg Vogler, Scott Waddell, Wanpeng Wang, Rachel I Wilson, Mariana F Wolfner, Yiu-Cheung E Wong, Anthony Xie, Jun Xu, Shinya Yamamoto, Jia Yan, Zepeng Yao, Kazuki Yoda, Ruijun Zhu, Robert P Zinzen

Duncan NRI Faculty and Staff Publications

For more than 100 years, the fruit fly Drosophila melanogaster has been one of the most studied model organisms. Here, we present a single-cell atlas of the adult fly, Tabula Drosophilae, that includes 580,000 nuclei from 15 individually dissected sexed tissues as well as the entire head and body, annotated to >250 distinct cell types. We provide an in-depth analysis of cell type-related gene signatures and transcription factor markers, as well as sexual dimorphism, across the whole animal. Analysis of common cell types between tissues, such as blood and muscle cells, reveals rare cell types and tissue-specific subtypes. This …

Daam2 Regulates Myelin Structure And The Oligodendrocyte Actin Cytoskeleton Through Rac1 And Gelsolin, Carlo D Cristobal, Chih-Yen Wang, Zhongyuan Zuo, Joshua A Smith, Aaron Lindeke-Myers, Hugo J Bellen, Hyun Kyoung Lee

Duncan NRI Faculty and Staff Publications

Myelin is essential to neuronal health and CNS function, and oligodendrocytes (OLs) undergo a complex process of cytoskeletal remodeling to form compact myelin sheaths. We previously discovered that a formin protein, Dishevelled associated activator of morphogenesis 2 (Daam2), suppresses OL differentiation through Wnt signaling; however, its role in cytoskeletal control remains unknown. To investigate this, we used OL-specific Daam2 conditional knockout (Daam2 cKO) mice of either sex and found myelin decompaction during an active period of myelination in postnatal development and motor coordination deficits in adulthood. Using primary OL cultures, we found Daam2-depleted OLs showed morphologic dysregulation during differentiation, suggesting …

Clinical Exome Sequencing Data Reveal High Diagnostic Yields For Congenital Diaphragmatic Hernia Plus (Cdh+) And New Phenotypic Expansions Involving Cdh, Tiana M Scott, Ian M Campbell, Andres Hernandez-Garcia, Seema R Lalani, Pengfei Liu, Chad A Shaw, Jill A Rosenfeld, Daryl A Scott

Duncan NRI Faculty and Staff Publications

Background: Congenital diaphragmatic hernia (CDH) is a life-threatening birth defect that often co-occurs with non-hernia-related anomalies (CDH+). While copy number variant (CNV) analysis is often employed as a diagnostic test for CDH+, clinical exome sequencing (ES) has not been universally adopted.

Methods: We analysed a clinical database of ~12 000 test results to determine the diagnostic yields of ES in CDH+ and to identify new phenotypic expansions.

Results: Among the 76 cases with an indication of CDH+, a molecular diagnosis was made in 28 cases for a diagnostic yield of 37% (28/76). A provisional diagnosis was made in seven other …

Blood–Brain Barrier Disruption Mediated By Ffa1 Receptor—Evidence Using Miniscope, Kristen L Lindenau, Jeffrey L Barr, Christopher R Higgins, Kevin T Sporici, Eugen Brailoiu, Gabriela C Brailoiu

Faculty, Staff and Student Publications

Omega-3 polyunsaturated fatty acids (n-3 PUFAs), obtained from diet and dietary supplements, have been tested in clinical trials for the prevention or treatment of several diseases. n-3 PUFAs exert their effects by activation of free fatty acid (FFA) receptors. FFA1 receptor, expressed in the pancreas and brain, is activated by medium- to long-chain fatty acids. Despite some beneficial effects on cognition, the effects of n-3 PUFAs on the blood-brain barrier (BBB) are not clearly understood. We examined the effects of FFA1 activation on BBB permeability in vitro, using rat brain microvascular endothelial cells (RBMVEC), and in vivo, by assessing Evans …

Recent Insights Into The Role Of Glia And Oxidative Stress In Alzheimer’S Disease Gained From Drosophila, Lindsey D Goodman, Hugo J Bellen

Duncan NRI Faculty and Staff Publications

Here, we discuss findings made using Drosophila on Alzheimer's disease (AD) risk and progression. Recent studies have investigated the mechanisms underlying glia-mediated neuroprotection in AD. First, we discuss a novel mechanism of glial lipid droplet formation that occurs in response to elevated reactive oxygen species in neurons. The data suggest that disruptions to this process contribute to AD risk. We further discuss novel mechanistic insights into glia-mediated Aβ42-clearance made using the fly. Finally, we highlight work that provides evidence that the aberrant accumulation of reactive oxygen species in AD may not just be a consequence of disease but contribute to …

Disruption Of Mecp2-Tcf20 Complex Underlies Distinct Neurodevelopmental Disorders, Jian Zhou, Hamdan Hamdan, Hari Krishna Yalamanchili, Kaifang Pang, Amy E Pohodich, Joanna Lopez, Yingyao Shao, Juan A Oses-Prieto, Lifang Li, Wonho Kim, Mark A Durham, Sameer S Bajikar, Donna J Palmer, Philip Ng, Michelle L Thompson, E Martina Bebin, Amelie J Müller, Alma Kuechler, Antje Kampmeier, Tobias B Haack, Alma L Burlingame, Zhandong Liu, Matthew N Rasband, Huda Y Zoghbi

Duncan NRI Faculty and Staff Publications

MeCP2 is associated with Rett syndrome (RTT), MECP2 duplication syndrome, and a number of conditions with isolated features of these diseases, including autism, intellectual disability, and motor dysfunction. MeCP2 is known to broadly bind methylated DNA, but the precise molecular mechanism driving disease pathogenesis remains to be determined. Using proximity-dependent biotinylation (BioID), we identified a transcription factor 20 (TCF20) complex that interacts with MeCP2 at the chromatin interface. Importantly, RTT-causing mutations in MECP2 disrupt this interaction. TCF20 and MeCP2 are highly coexpressed in neurons and coregulate the expression of key neuronal genes. Reducing Tcf20 partially rescued the behavioral deficits caused …

Loss Of Irf2bpl Impairs Neuronal Maintenance Through Excess Wnt Signaling, Paul C Marcogliese, Debdeep Dutta, Shrestha Sinha Ray, Nghi D P Dang, Zhongyuan Zuo, Yuchun Wang, Di Lu, Fatima Fazal, Thomas A Ravenscroft, Hyunglok Chung, Oguz Kanca, Jijun Wan, Emilie D Douine, Undiagnosed Diseases Network, Loren D M Pena, Shinya Yamamoto, Stanley F Nelson, Matthew Might, Kathrin C Meyer, Nan Cher Yeo, Hugo J Bellen

Duncan NRI Faculty and Staff Publications

De novo truncations in Interferon Regulatory Factor 2 Binding Protein Like (IRF2BPL) lead to severe childhood-onset neurodegenerative disorders. To determine how loss of IRF2BPL causes neural dysfunction, we examined its function in Drosophila and zebrafish. Overexpression of either IRF2BPL or Pits, the Drosophila ortholog, represses Wnt transcription in flies. In contrast, neuronal depletion of Pits leads to increased wingless (wg) levels in the brain and is associated with axonal loss, whereas inhibition of Wg signaling is neuroprotective. Moreover, increased neuronal expression of wg in flies is sufficient to cause age-dependent axonal loss, similar to reduction …

Impairment Of Autophagy After Spinal Cord Injury Potentiates Neuroinflammation And Motor Function Deficit In Mice, Yun Li, Zhuofan Lei, Rodney M Ritzel, Junyun He, Hui Li, Harry M C Choi, Marta M Lipinski, Junfang Wu

Faculty, Staff and Student Publications

Autophagy is a catabolic process that degrades cytoplasmic constituents and organelles in the lysosome, thus serving an important role in cellular homeostasis and protection against insults. We previously reported that defects in autophagy contribute to neuronal cell damage in traumatic spinal cord injury (SCI). Recent data from other inflammatory models implicate autophagy in regulation of immune and inflammatory responses, with low levels of autophagic flux associated with pro-inflammatory phenotypes. In the present study, we examined the effects of genetically or pharmacologically manipulating autophagy on posttraumatic neuroinflammation and motor function after SCI in mice.

Methods: Young adult male C57BL/6, CX3CR1-GFP, autophagy …

A T-Cell Engaging Bispecific Antibody With A Tumor-Selective Bivalent Folate Receptor Alpha Binding Arm For The Treatment Of Ovarian Cancer, Brian C Avanzino, Kirthana Prabhakar, Pranjali Dalvi, Sharon Hartstein, Hannes Kehm, Aarti Balasubramani, Andrew A Boudreau, Ben Buelow, Karen Chang, Laura M Davison, Suhasini Iyer, Vidyut Kalwit, Kristin Lewis Wilson, Harbani K Malik-Chaudhry, Will Pierson, Geovanni Pineda, Udaya S Rangaswamy, Sowmya Saiganesh, Ute Schellenberger, Harshad S Ugamraj, Rodolfovan D Yabut, Roland Buelow, Jocelyn Chapman, Nathan D Trinklein, Katherine E Harris

Faculty, Staff and Student Publications

The use of T-cell engagers (TCEs) to treat solid tumors is challenging, and several have been limited by narrow therapeutic windows due to substantial on-target, off-tumor toxicities due to the expression of low levels of target antigens on healthy tissues. Here, we describe TNB-928B, a fully human TCE that has a bivalent binding arm for folate receptor alpha (FRα) to selectively target FRα overexpressing tumor cells while avoiding the lysis of cells with low levels of FRα expression. The bivalent design of the FRα binding arm confers tumor selectivity due to low-affinity but high-avidity binding to high FRα antigen density …

Functional Studies Of Genetic Variants Associated With Human Diseases In Notch Signaling-Related Genes Using Drosophila, Sheng-An Yang, Jose L Salazar, David Li-Kroeger, Shinya Yamamoto

Duncan NRI Faculty and Staff Publications

Rare variants in the many genes related to Notch signaling cause diverse Mendelian diseases that affect myriad organ systems. In addition, genome- and exome-wide association studies have linked common and rare variants in Notch-related genes to common diseases and phenotypic traits. Moreover, somatic mutations in these genes have been observed in many types of cancer, some of which are classified as oncogenic and others as tumor suppressive. While functional characterization of some of these variants has been performed through experimental studies, the number of ‘variants of unknown significance’ identified in patients with diverse conditions keeps increasing as high-throughput sequencing technologies …

Advancements In The Quest To Map, Monitor, And Manipulate Neural Circuitry, Jessica L Swanson, Pey-Shyuan Chin, Juan M Romero, Snigdha Srivastava, Joshua Ortiz-Guzman, Patrick J Hunt, Benjamin R Arenkiel

Duncan NRI Faculty and Staff Publications

Neural circuits and the cells that comprise them represent the functional units of the brain. Circuits relay and process sensory information, maintain homeostasis, drive behaviors, and facilitate cognitive functions such as learning and memory. Creating a functionally-precise map of the mammalian brain requires anatomically tracing neural circuits, monitoring their activity patterns, and manipulating their activity to infer function. Advancements in cell-type-specific genetic tools allow interrogation of neural circuits with increased precision. This review provides a broad overview of recombination-based and activity-driven genetic targeting approaches, contemporary viral tracing strategies, electrophysiological recording methods, newly developed calcium, and voltage indicators, and neurotransmitter/neuropeptide biosensors …

Bi-Allelic Variants In Ogdhl Cause A Neurodevelopmental Spectrum Disease Featuring Epilepsy, Hearing Loss, Visual Impairment, And Ataxia, Zheng Yie Yap, Stephanie Efthymiou, Simone Seiffert, Karen Vargas Parra, Sukyeong Lee, Alessia Nasca, Reza Maroofian, Isabelle Schrauwen, Manuela Pendziwiat, Sunhee Jung, Elizabeth Bhoj, Pasquale Striano, Kshitij Mankad, Barbara Vona, Sanmati Cuddapah, Anja Wagner, Javeria Raza Alvi, Elham Davoudi-Dehaghani, Mohammad-Sadegh Fallah, Srinitya Gannavarapu, Costanza Lamperti, Andrea Legati, Bibi Nazia Murtaza, Muhammad Shahid Nadeem, Mujaddad Ur Rehman, Kolsoum Saeidi, Vincenzo Salpietro, Sarah Von Spiczak, Abigail Sandoval, Sirous Zeinali, Massimo Zeviani, Adi Reich, Synaps Study Group, University Of Washington Center For Mendelian Genomics, Cholsoon Jang, Ingo Helbig, Tahsin Stefan Barakat, Daniele Ghezzi, Suzanne M Leal, Yvonne Weber, Henry Houlden, Wan Hee Yoon

Faculty, Staff and Students Publications

The 2-oxoglutarate dehydrogenase-like (OGDHL) protein is a rate-limiting enzyme in the Krebs cycle that plays a pivotal role in mitochondrial metabolism. OGDHL expression is restricted mainly to the brain in humans. Here, we report nine individuals from eight unrelated families carrying bi-allelic variants in OGDHL with a range of neurological and neurodevelopmental phenotypes including epilepsy, hearing loss, visual impairment, gait ataxia, microcephaly, and hypoplastic corpus callosum. The variants include three homozygous missense variants (p.Pro852Ala, p.Arg244Trp, and p.Arg299Gly), three compound heterozygous single-nucleotide variants (p.Arg673Gln/p.Val488Val, p.Phe734Ser/p.Ala327Val, and p.Trp220Cys/p.Asp491Val), one homozygous frameshift variant (p.Cys553Leufs∗16), and one homozygous stop-gain variant (p.Arg440Ter). To support the …

Usability Of Abattoir-Acquired Pig Eyes For Refractive Excimer Laser Research, Marius Topka, Yao Zhang, Antonia Bock, Peter Riedel, Johannes Lörner, Alexander Hammer, Eva Maier, Friedrich Paulsen, Christian M Hammer

Faculty, Staff and Student Publications

The purpose of this study was to elucidate, under which conditions abattoir-acquired pig eyes are suitable for refractive excimer laser experiments. Porcine eyes from tunnel-scalded (n = 5) and tank-scalded (n = 10) pigs were compared to unscalded eyes (n = 5) and to eyes scalded in the laboratory (n = 5). The corneal epithelium was removed before an excimer laser was used to perform a - 8.0 D photoablation. Corneal thickness was measured by optical coherence topography before and after photoablation. The ablation depth was determined with a contour measuring station, the morphology of the ablated areas was characterized …

Exogenous Inter-Α Inhibitor Proteins Prevent Cell Death And Improve Ischemic Stroke Outcomes In Mice, Louise D Mccullough, Meaghan Roy-O'Reilly, Yun-Ju Lai, Anthony Patrizz, Yan Xu, Juneyoung Lee, Aleah Holmes, Daniel C Kraushaar, Anjali Chauhan, Lauren H Sansing, Barbara S Stonestreet, Liang Zhu, Julia Kofler, Yow-Pin Lim, Venugopal Reddy Venna

Faculty, Staff and Students Publications

Inter-α inhibitor proteins (IAIPs) are a family of endogenous plasma and extracellular matrix molecules. IAIPs suppress proinflammatory cytokines, limit excess complement activation, and bind extracellular histones to form IAIP-histone complexes, leading to neutralization of histone-associated cytotoxicity in models of sepsis. Many of these detrimental processes also play critical roles in the pathophysiology of ischemic stroke. In this study, we first assessed the clinical relevance of IAIPs in stroke and then tested the therapeutic efficacy of exogenous IAIPs in several experimental stroke models. IAIP levels were reduced in both ischemic stroke patients and in mice subjected to experimental ischemic stroke when …

Macrocyclic Immunoproteasome Inhibitors As A Potential Therapy For Alzheimer's Disease, Min Jae Lee, Deepak Bhattarai, Hyeryung Jang, Ahreum Baek, In Jun Yeo, Seongsoo Lee, Zachary Miller, Sukyeong Lee, Jin Tae Hong, Dong-Eun Kim, Wooin Lee, Kyung Bo Kim

Faculty, Staff and Students Publications

Previously, we reported that immunoproteasome (iP)-targeting linear peptide epoxyketones improve cognitive function in mouse models of Alzheimer's disease (AD) in a manner independent of amyloid β. However, these compounds' clinical prospect for AD is limited due to potential issues, such as poor brain penetration and metabolic instability. Here, we report the development of iP-selective macrocyclic peptide epoxyketones prepared by a ring-closing metathesis reaction between two terminal alkenes attached at the P2 and P3/P4 positions of linear counterparts. We show that a lead macrocyclic compound DB-60 (

Neurovascular Regulation In Diabetic Retinopathy And Emerging Therapies, Liyang Ji, Hong Tian, Keith A Webster, Wei Li

Faculty, Staff and Students Publications

Diabetic retinopathy (DR) is the leading cause of vision loss in working adults in developed countries. The disease traditionally classified as a microvascular complication of diabetes is now widely recognized as a neurovascular disorder resulting from disruption of the retinal neurovascular unit (NVU). The NVU comprising retinal neurons, glia and vascular cells coordinately regulates blood flow, vascular density and permeability to maintain homeostasis. Disturbance of the NVU during DR can lead to vision-threatening clinical manifestations. A limited number of signaling pathways have been identified for intercellular communication within the NVU, including vascular endothelial growth factor (VEGF), the master switch for …

Intermittent Hypoxia And Effects On Early Learning/Memory: Exploring The Hippocampal Cellular Effects Of Pediatric Obstructive Sleep Apnea, Arvind Chandrakantan, Adam C Adler, Mehmet Tohsun, Farrah Kheradamand, Russell S Ray, Steven Roth

Faculty, Staff and Students Publications

This review provides an update on the neurocognitive phenotype of pediatric obstructive sleep apnea (OSA). Pediatric OSA is associated with neurocognitive deficits involving memory, learning, and executive functioning. Adenotonsillectomy (AT) is presently accepted as the first-line surgical treatment for pediatric OSA, but the executive function deficits do not resolve postsurgery, and the timeline for recovery remains unknown. This finding suggests that pediatric OSA potentially causes irreversible damage to multiple areas of the brain. The focus of this review is the hippocampus, 1 of the 2 major sites of postnatal neurogenesis, where new neurons are formed and integrated into existing circuitry …

Deciphering An Agrp-Serotoninergic Neural Circuit In Distinct Control Of Energy Metabolism From Feeding, Yong Han, Guobin Xia, Dollada Srisai, Fantao Meng, Yanlin He, Yali Ran, Yang He, Monica Farias, Giang Hoang, István Tóth, Marcelo O Dietrich, Miao-Hsueh Chen, Yong Xu, Qi Wu

Children’s Nutrition Research Center Staff Publications

Contrasting to the established role of the hypothalamic agouti-related protein (AgRP) neurons in feeding regulation, the neural circuit and signaling mechanisms by which they control energy expenditure remains unclear. Here, we report that energy expenditure is regulated by a subgroup of AgRP neurons that send non-collateral projections to neurons within the dorsal lateral part of dorsal raphe nucleus (dlDRN) expressing the melanocortin 4 receptor (MC4R), which in turn innervate nearby serotonergic (5-HT) neurons. Genetic manipulations reveal a bi-directional control of energy expenditure by this circuit without affecting food intake. Fiber photometry and electrophysiological results indicate that the thermo-sensing MC4RdlDRN neurons …

The Synergy Of Bet Inhibitors With Aurora A Kinase Inhibitors In Mycn-Amplified Neuroblastoma Is Heightened With Functional Tp53, Joanna S Yi, Oscar Sias-Garcia, Nicole Nasholm, Xiaoyu Hu, Amanda Balboni Iniguez, Matthew D Hall, Mindy Davis, Rajarshi Guha, Myrthala Moreno-Smith, Eveline Barbieri, Kevin Duong, Jessica Koach, Jun Qi, James E Bradner, Kimberly Stegmaier, William A Weiss, W Clay Gustafson

Faculty, Staff and Students Publications

Amplification of MYCN is a poor prognostic feature in neuroblastoma (NBL) indicating aggressive disease. We and others have shown BET bromodomain inhibitors (BETi) target MYCN indirectly by downregulating its transcription. Here we sought to identify agents that synergize with BETi and to identify biomarkers of resistance. We previously performed a viability screen of ∼1,900 oncology-focused compounds combined with BET bromodomain inhibitors against MYCN-amplified NBL cell lines. Reanalysis of our screening results prominently identified inhibitors of aurora kinase A (AURKAi) to be highly synergistic with BETi. We confirmed the anti-proliferative effects of several BETi+AURKAi combinations in MYCN-amplified NBL cell lines. Compared …

A Biallelic Pathogenic Variant In The Ogdh Gene Results In A Neurological Disorder With Features Of A Mitochondrial Disease, Zheng Yie Yap, Klaudia Strucinska, Satoshi Matsuzaki, Sukyeong Lee, Yue Si, Kenneth Humphries, Mark A Tarnopolsky, Wan Hee Yoon

Faculty, Staff and Students Publications

2-Oxoglutarate dehydrogenase (OGDH) is a rate-limiting enzyme in the mitochondrial TCA cycle, encoded by the OGDH gene. α-Ketoglutarate dehydrogenase (OGDH) deficiency was previously reported in association with developmental delay, hypotonia, and movement disorders and metabolic decompensation, with no genetic data provided. Using whole exome sequencing, we identified two individuals carrying a homozygous missense variant c.959A>G (p.N320S) in the OGDH gene. These individuals presented with global developmental delay, elevated lactate, ataxia and seizure. Fibroblast analysis and modeling of the mutation in Drosophila were used to evaluate pathogenicity of the variant. Skin fibroblasts from subject # 2 showed a decrease in …