Digital Commons Network^™

Therapeutic Radiation Drives Leptomeningeal Dissemination Of Medulloblastoma Through An Innate Immune Process, Carolina Nör, Kaitlin Kharas, Alex Rasnitsyn, Maria C Vladoiu, Nam Woo Cho, Jacob S Young, Felipe Nör, Ncedile Mankahla, Joonas Haapasalo, Kristiina Nordfors, Sara Rapic, Patryk Skowron, Raúl A Suárez, Alexander T Bahcheli, Oliver Ocsenas, Xin Chen, Shahrzad Bahrampour, Ali Momin, Lakshmikirupa Sundaresan, Winnie Ong, Liam D Hendrikse, Namal Abeysundara, Kyle Juraschka, Michelle Ly, Jonelle G Pallota, Tajana Douglas, Ning Huang, Hao Wang, Esta Mak, Lei Qin, Jessica Liu, Lily Shen, Betty Luu, Alex Manno, Sachin A Kumar, Laura K Donovan, Vernon Fong, Cory Richman, Craig Daniels, Livia Garzia, Jeremy N Rich, Cynthia Hawkins, Xiaochong Wu, Ralph Dacosta, Jüri Reimand, Xi Huang, Vijay Ramaswamy, David R Raleigh, Michael D Taylor

Faculty, Staff and Students Publications

Leptomeningeal metastases are the most important source of morbidity and mortality for medulloblastoma patients. Radiation of the entire brain is highly effective in the treatment and/or prevention of medulloblastoma leptomeningeal metastases. Infants treated on clinical trials with focal tumor radiation recur metastatically, whereas infants treated with only chemotherapy relapse locally. In murine medulloblastoma model systems, provision of a single dose of radiation to the tumor drives leptomeningeal dissemination. An inflammatory response after radiation-induced tumor cell death recruits a variety of immune cells. Inflammation opens the local blood-brain barrier, allowing intravasation of medulloblastoma cells. Experimental induction of inflammation with lipopolysaccharide drives …

Overexpression Of The Signaling Coordinator Gab2 Can Play An Important Role In Acute Myeloid Leukemia Progression, Michael H. Kramer, Stephanie N. Richardson, Yang Li, Tiankai Yin, Nichole M. Helton, Daniel R. George, Michelle Cai, Sai Mukund Ramakrishnan, Casey Ds Katerndahl, Christopher A. Miller, Timothy J. Ley

2020-Current year OA Pubs

Mutations that initiate acute myeloid leukemia (AML) can cause clonal expansion without transformation (clonal hematopoiesis). Cooperating mutations, usually in signaling genes, are needed to cause overt disease, but these may require a specific fitness state to be tolerated. Here, we show that nearly all AMLs arising in a mouse model expressing 2 common AML-initiating mutations (Dnmt3aR878H and Npm1cA) acquired a single copy amplification of chromosome 7 (chr7), followed by activating mutations in signaling genes. We show that overexpression of a single gene on chr7 (Gab2, which coordinates signaling pathways) was tolerated in the presence of the Npm1cA mutation, could accelerate …

Muscle Fatigue Arising Intrinsically From Sur2- But Not Kir6.1-Dependent Gain-Of-Function In Cantu Syndrome Mice, Rosa Scala, Maya Mukadam, Yuezhou Chen, Courtney Frazier, Nathaniel W York, Robert C Tryon, Gretchen A Meyer, Colin G Nichols

2020-Current year OA Pubs

Cantu syndrome (CS) is a rare disease caused by gain-of-function (GOF) mutations of Kir6.1 or SUR2 subunits of ATP-sensitive potassium (KATP) channels. CS patients with SUR2 and Kir6.1 variants display a similar constellation of symptoms, including muscle weakness and fatigue. The effects of CS mutations on skeletal muscle KATP channels, and any consequent direct effects on contractility, are currently unclear. Here, we used two knock-in mouse models of CS, respectively, carrying GOF mutations Kir6.1[V65M] or SUR2[A478V], to assess KATP channel properties and contractility in isolated fast-twitch extensor digitorum longus (EDL) and slow-twitch soleus (SOL) muscles. Electrophysiological recordings in isolated myofibers …

Integrative Proteogenomics And Forward Genetics Reveal A Novel Mitotic Vulnerability In Triple-Negative Breast Cancer, Nicholas J Neill, Shankha Satpathy, Karsten Krug, Jitendra K Meena, Nivetha Ramesh Babu, Cheyenne Calderon, Desmon Reed, Marcus J Weber, Lacey E Dobrolecki, Alaina Lewis, Christina Sallas, Meenakshi Anurag, Kimberly R Holloway, Chen Huang, Suhas Vasaikar, Maria F Cardenas, Beom-Jun Kim, Doug W Chan, Shayan C Avanessian, Siddhartha Tyagi, Mayra Orellana, Sufeng Mao, Heyuan Li, Fade Gong, Sarah J Kurley, Kristen L Meerbrey, Calla M Olson, Amritha Nair, Tingting Sun, Hsiang-Ching Chung, Elizabeth A Bowling, Jarey H Wang, Pengju Zhang, Peng Xiao, Duxiao Yang, Fabio Stossi, Mei-Yin C Polley, Alexander B Saltzman, Filip Mundt, D R Mani, Michael A Gillette, Susan G Hilsenbeck, George Miles, Carolina Gutierrez, C Kent Osborne, Charles Y Lin, Nathanael S Gray, Jinpeng Sun, David A Wheeler, Charles M Perou, Anna Malovannaya, Michael T Lewis, Bing Zhang, Matthew J Ellis, Steven A Carr, Thomas F Westbrook

Faculty, Staff and Students Publications

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with few effective targeted therapies. Taxanes and other microtubule-targeting agents (MTAs) are frontline chemotherapies for TNBC; however, the molecular pathways that cause TNBC taxane sensitivity are largely unknown, preventing selection of taxane-responsive patients and development of more selective therapeutic strategies. In this study, we identified tumor-selective vulnerabilities in TNBC harboring inactivation of the tumor suppressor PTPN12 by integrating proteogenomic characterization and synthetic lethality screening. We discovered that PTPN12 inactivation drives mitotic defects through aberrant hyperactivation of the ubiquitin ligase complex APCFZR1, a critical regulator of the cell cycle. Consistent …

Direct-In-Nod Genetic Ablation Of Bcl3 Leads To Complete Type 1 Diabetes Protection., Jeremy Racine, Jennifer R Dwyer, Harold D Chapman, Amy Bell, Raymond F. Robledo, David V. Serreze

Faculty Research 2025

It was previously reported that genetic ablation of the NF-κB atypical inhibitor Bcl3 through congenic introduction of a 129P2-embryo derived knockout allele (Bcl3tm1Ver) accelerated autoimmune diabetes in the NOD mouse model. Conversely, we found that direct CRISPR-mediated ablation of this gene in the NOD/ShiLtDvs substrain completely inhibited diabetes development. Our CRISPR approach excised exons 3-7 within the NOD Bcl3 gene. These new NOD-Bcl3-/- mice had very low levels of insulitis, indicating protective mechanisms elicited early in the disease process. Dissimilar to reports of Bcl3 ablation in nonautoimmune C57BL/6-background mice, we found that splenic and lymph node B cells were not …

From Human To Mouse And Back Again: Genetic And Genomic Ta(I)Les Of Islet Dysfunction In Type 2 Diabetes., Romy Kursawe, Khushdeep Bandesh, Sai Nivedita Krishnan, Kevin S Liu, Redwan M Bhuiyan, Michael L. Stitzel

Faculty Research 2025

Type 2 diabetes (T2D) is a complex genetic disease with substantial environmental inputs leading to glucose homeostasis defects. Insulin production is central to proper glucose control, and islet cell dysfunction and death lie at the nexus of T2D genetics and pathophysiology. Comprehensive identification of genes and pathways contributing to these processes is essential for mechanistic understanding and therapeutic targeting. Here, we summarize the latest human and mouse T2D genetic and genomic studies and assess how these parallel variant-to-function efforts and associated data contribute convergent or complementary insights and new opportunities to dissect T2D islet (dys)function. We distill mechanistic and phenotypic …

Complete Genome Assemblies Of Two Mouse Subspecies Reveal Structural Diversity Of Telomeres And Centromeres., Bailey A Francis, Landen Gozashti, Kevin Costello, Takaoki Kasahara, Olivia S Harringmeyer, Jingtao Lilue, Tianzhen Wu, Katarzyna Zoltowska, Mohab Helmy, Tadafumi Kato, Anne M Czechanski, Iraad F Bronner, Emma Dawson, Michael A Quail, Anne Ferguson-Smith, Laura G Reinholdt, David J Adams, Thomas M Keane

Faculty Research 2025

It has been more than 20 years since the publication of the C57BL/6J mouse reference genome, which has been a key catalyst for understanding the biology of mammalian diseases. However, the mouse reference genome still lacks telomeres and centromeres, contains 281 chromosomal sequence gaps and only partially represents many biomedically relevant loci. Here we present the first telomere-to-telomere (T2T) mouse genomes for two key inbred strains, C57BL/6J and CAST/EiJ. These T2T genomes reveal substantial variability in telomere and centromere sizes and structural organization. We thus add an additional 213 Mb of new sequence to the reference genome, which contains 517 …

‘Earth System Engineers’ And The Cumulative Impact Of Organisms In Deep Time, Simon A. F. Darroch, Michelle M. Casey, Alison T. Cribb, Amanda E. Bates, Matthew E. Clapham, Dori L. Contreras, Matthew Craffey, Ivo A. P. Duijnstee, William Gearty, Nicholas J. Gotelli, Marcus J. Hamilton, Riley F. Hayes, Pincelli M. Hull, Daniel E. Ibarra, V. A. Korasidis, Jaemin Lee, Cindy V. Looy, Tyler R. Lyson, Benjamin Muddiman, Peter D. Roopnarine, Alex B. Shupinski, Felisa A. Smith, Alycia L. Stigall, Catalina P. Tomé, Katherine A. Turk, Amelia Villaseñor, Peter J. Wagner, Steve C. Wang, S. Kathleen Lyons

College of Life Sciences Faculty Papers

Understanding the role of humans as 'ecosystem engineers' requires a deep-time perspective rooted in evolutionary history and the fossil record. However, no conceptual framework exists for studying the rise of ecosystem engineering in deep time, requiring us to consider effects that fall outside the scope of traditional definitions. Here, we present a new framework applicable to both modern and ancient engineering-type effects. We propose a new term - 'Earth system engineering' - to describe biological processes that alter the structure and function of planetary spheres, and which combines core tenets of ecosystem engineering, niche construction, and legacy effects. We illustrate …

The Genomes Of Nematode-Trapping Fungi Provide Insights Into The Origin And Diversification Of Fungal Carnivorism, Yani Fan, Minghao Du, Weiwei Zhang, Wei Deng, Ence Yang, Shunxian Wang, Luwen Yan, Liao Zhang, Seogchan Kang, Jacob L Steenwyk, Zhiqiang An, Xingzhong Liu, Meichun Xiang

The Brown Foundation: Institute of Molecular Medicine

Nematode-trapping fungi (NTF), most of which belong to a monophyletic lineage in Ascomycota, cannibalize nematodes and other microscopic animals, raising questions regarding the types and mechanisms of genomic changes that enabled carnivorism and adaptation to the carbon-rich and nitrogen-poor environment created by the Permian-Triassic extinction event. To address these questions, we conducted comparative genomic analyses of 21 NTF and 21 non-NTF. Carnivorism-associated changes include expanded genes for nematode capture, infection, and consumption (e.g., adhesive proteins, CAP superfamily, eukaryotic aspartyl proteases, and serine-type peptidases). Although the link between secondary metabolite (SM) production and carnivorism remains unclear, we found that the number …

Iron Supplementation Switches Mode Of Cell Death To Ferroptosis During Acetaminophen-Induced Liver Injury In Mice Rendering It Resistant To N-Acetylcysteine., Olamide B. Adelusi, Aparna Venkatraman, Jephte Y. Akakpo, Anup Ramachandran, Hartmut Jaeschke

Manuscripts, Articles, Book Chapters and Other Papers

Acetaminophen (APAP) overdose can cause liver injury and is the leading cause of acute liver failure in Western countries. Hepatocellular necrosis induced by APAP involves the formation of a reactive metabolite, triggering mitochondrial oxidant stress and peroxynitrite formation. Iron-catalyzed protein nitration is critical for mitochondrial dysfunction and cell death in the absence of lipid peroxidation (LPO). However, co-treatment of APAP and ferrous sulfate aggravated protein nitration and liver injury but also triggered extensive LPO (measured as malondialdehyde and hydroxy eicosatetraenoic acid (HETE) species). The objective of this study was to evaluate whether the aggravated injury under these conditions is caused …

Targeting The Hippo Pathway For Cardiac Regeneration, Rich Gang Li, Fansen Meng, James F Martin

Faculty, Staff and Students Publications

Ischemic heart disease, which affects more than 200 million people worldwide, is caused by reduced blood flow to the heart and leads to widespread cardiomyocyte death. Due to the limited regenerative potential of cardiomyocytes, the lost tissue is replaced by a fibrotic scar, resulting in reduced cardiac function and progression to heart failure. Current therapeutic interventions aim to improve blood flow but cannot address the inability of cardiomyocytes to renew after injury. However, multiple studies have shown that modulating the Hippo signaling pathway to activate Yes-associated protein (YAP), a transcription coactivator, in adult murine and porcine cardiomyocytes induces robust cardiomyocyte …

Protein Kinase Giα Oxidation Negatively Regulates Antibody Production By B Cells, Hyun-Ju Cho, Rebecca L Charles, Oleksandra Prysyazhna, Sapna Arjun, Asvi A Francois, Kevin M Mcbride, Philip Eaton

Faculty, Staff and Student Publications

Endogenous oxidants induce a C42-dependent interprotein disulfide between the subunits of protein kinase G (PKG) Iα in cardiovascular tissues to control blood pressure and ventricular relaxation during diastole. PKGIα is expressed in other cell types, including those of the immune system, where the redox state of this kinase is likely to regulate other important physiological processes. The role of PKGIα oxidation in antibody production by B cells, which produce oxidants such as hydrogen peroxide during differentiation, was examined by comparing the immune response of oxidation-resistant C42S PKGIα knock-in (KI) mice to their wild type (WT) littermates.

Immunization with the 4 …

Apol2 Stabilizes Ku80 To Confer Nhej-Mediated Radioresistance In Gastric Cancer, Dan Zu, Qimei Bao, Hanyi He, Yuke Zhong, Mingcong Deng, Yangchan Hu, Chunkai Zhang, Chen Liang, Yixing Huang, Haidong Liu, Xiao Li, Yanhua He, Guoyan Luo, Weixin Wu, Fenghui Guan, Shengfeng Xu, Min Liu, Albino Bacolla, Ji Jing, Yian Du, John A Tainer, Yin Shi, Zu Ye, Xiangdong Cheng

Faculty, Staff and Student Publications

Radiotherapy is one of the most important adjuvant treatment methods for gastric cancer (GC). However, radioresistance remains a major clinical obstacle. In this study, APOL2 is identified as a key player in promoting non-homologous end joining (NHEJ)-mediated double-strand break (DSB) repair and enhancing radioresistance in GC. Bioinformatics and clinical data revealed that high APOL2 expression is correlated with poor prognosis in GC patients. Functional experiments showed that APOL2 overexpression enhances genomic stability by accelerating DSB repair via the NHEJ pathway, while APOL2 knockout impairs repair capacity. Mechanistically, APOL2 binds to and stabilizes Ku80 by enhancing USP7-mediated deubiquitylation, thereby increasing Ku80 …

Sensory-Selective Peripheral And Neuraxial Nerve Blockade With 2',6'-Pipecoloxylidide, Claire A Ostertag-Hill, Shuanglong Chen, Tianrui Xue, Rachelle Shao, Matthew Torre, Bin Feng, Zahra Vahedi, Longtu Chen, Steven J Staffa, Yueqin Zheng, Daniel S Kohane

Duncan NRI Faculty and Staff Publications

Background: Safe sensory-selective local anesthetics would be a major advance in the management of acute and chronic pain. This articles describes the sensory-selective local anesthetic properties and the toxicity profile of a known metabolite of amino-amide local anesthetics, 2',6'-pipecoloxylidide (PPX).

Methods: PPX was synthesized and made into its hydrochloride salt. PPX or ropivacaine (ROP) were injected at the sciatic nerve or intrathecally in rats, who then underwent modified hotplate (sensory) testing and weight-bearing (motor) testing. Rats injected with PPX or ROP were assessed for clinical toxicity endpoints. Conduction blockade was studied with single-unit recordings in mice. Biocompatibility was assessed histologically. …

Degenerating Intervertebral Discs In The Streptozotocin-High-Fat Diet Model Of Type 2 Diabetes Show Extensive Inflammation, Christian E Gonzalez, Rachana S Vaidya, Sade W Clayton, Simon Y Tang

2020-Current year OA Pubs

The chronic inflammation observed during type 2 diabetes (T2D) is associated with spinal pathologies, including intervertebral disc (IVD) degeneration and chronic spine pain. Despite confounding factors, such as obesity, studies show that, after adjusting for age, body mass index and genetics (e.g. twins), patients with T2D experience disproportionate severity of IVD degeneration and/or back pain than individuals without T2D. We hypothesized that chronic T2D fosters a proinflammatory microenvironment within the IVD that promotes degeneration and disrupts homeostasis. To test this, we evaluated two common mouse models of T2D - leptin-receptor deficient (db/db) mice and mice with a chronic high-fat diet …

Glycerol-3-Phosphate Activates Chrebp, Fgf21 Transcription And Lipogenesis In Citrin Deficiency, Vinod Tiwari, Byungchang Jin, Olivia Sun, Edwin D J Lopez Gonzalez, Min-Hsuan Chen, Xiwei Wu, Hardik Shah, Andrew Zhang, Mark A Herman, Cassandra N Spracklen, Russell P Goodman, Charles Brenner

Faculty, Staff and Students Publications

Citrin deficiency (CD) is caused by the inactivation of SLC25A13, a mitochondrial membrane protein required to move electrons from cytosolic NADH to the mitochondrial matrix in hepatocytes. People with CD do not like sweets. Here we show that SLC25A13 loss causes the accumulation of glycerol-3-phosphate (G3P), which activates the carbohydrate response element-binding protein (ChREBP) to transcribe FGF21, which acts in the brain to restrain intake of sweets and alcohol and to transcribe key genes driving lipogenesis. Mouse and human data suggest that G3P-ChREBP is a mechanistic component of the Randle Cycle that contributes to metabolic-dysfunction-associated steatotic liver disease and forms …

Neurodevelopmental Abnormalities Underlying Behavioral Deficits In A Model Of Pediatric Obstructive Sleep Apnea, Arvind Chandrakantan, Michael R Williamson, Vaishnav Krishnan, Mahyar J Hedayatpour, Adam C Adler, Nandani Adyapak, Chris S Ward, Russell Ray, David Durgan, Farrah Kheradmand, Benjamin Deneen

Faculty, Staff and Students Publications

Rationale: Pediatric Obstructive Sleep Apnea (POSA) is a relatively common childhood sleep disorder whose neurodevelopmental phenotype includes deficits in learning and memory, olfaction, and fine motor abilities.

Objectives: To date, there has not been a validated preclinical model of POSA, hampering efforts in understanding how nocturnal episodes of intermittent hypoxia disrupt neurodevelopmental trajectories. The objective of this study was to create a faithful sculpting of the human condition in a preclinical murine model.

Methods: We used clinical data from children with POSA to develop and validate a mouse model of POSA that faithfully recapitulates several behavioral deficits seen in the …

Inhibition Of Bmper Mitigates Pulmonary Hypertension By Modulating Lrp1-Yap Interaction In Smooth Muscle Cells, Hua Mao, Claire M Li, Bing Sun, Christopher S Ward, Alan R Waich-Cohen, Ivan O Rosas, Howard J Huang, Harry Karmouty-Quintana, Liang Xie, Lavannya M Pandit, Xinchun Pi

Faculty, Staff and Students Publications

Background: BMPER (bone morphogenetic protein-binding endothelial regulator) is a secreted protein that is highly expressed in endothelial cells. It regulates the BMP (bone morphogenetic protein) pathway during vascular development and adulthood. Mutations in the BMP pathway are recognized as risk factors for pulmonary arterial hypertension group 1 pulmonary hypertension (PH). However, the roles of BMPER in pulmonary arterial hypertension remain unknown.

Methods: We assessed BMPER expression in Group 1 pulmonary arterial hypertension patient samples and examined its role in vascular remodeling using in vivo and in vitro approaches.

Results: BMPER level was elevated in pulmonary arterial hypertension lungs and significantly …

The Efficacy Of Longevity Interventions In Caenorhabditis Elegans Is Determined By The Early Life Activity Of Rna Splicing Factors, Sneha Dutta, Maria Camila Perez Matos, Caroline Heintz, Ayse Sena Mutlu, Mary Piper, Meeta Mistry, Arpit Sharma, Christopher S Morrow, Hannah Smith, Porsha Howell, Rohan Sehgal, Anne Lanjuin, Meng C Wang, William B Mair

Faculty, Staff and Students Publications

Geroscience aims to target the aging process to extend healthspan. However, even isogenic individuals show heterogeneity in natural aging rate and responsiveness to pro-longevity interventions, limiting translational potential. Using RNAseq analysis of young, isogenic, subpopulations of Caenorhabditis elegans selected solely on the basis of the splicing pattern of an in vivo minigene reporter that is predictive of future life expectancy, we find a strong correlation in young animals between predicted life span and alternative splicing of mRNAs related to lipid metabolism. The activity of two RNA splicing factors, Reversed Polarity-1 (REPO-1) and Splicing Factor 1 (SFA-1), early in life is …

Maternal Separation Disrupts Noradrenergic Control Of Adult Coping Behaviors, Chayla R Vazquez, Léa J Becker, Chao-Cheng Kuo, Solana A Cariello, Ayah N Hamdan, Ream Al-Hasani, Susan E Maloney, Jordan G Mccall

2020-Current year OA Pubs

Early life stress (ELS) profoundly impacts the brain and correlates with negative affective behaviors in adulthood. The locus coeruleus (LC), a stress-responsive brainstem nucleus that supplies most of the brain with norepinephrine (NE), is known to modulate negative affect. Using repeated maternal separation stress (MSS), we investigated the impact of ELS on the LC and stress-related behaviors in adulthood. We performed ex vivo cell-attached electrophysiology across the lifespan to reveal that MSS significantly increased LC firing during early development and adulthood but not in pre-adolescence and adolescence. We next examined potential changes in the expression of genes linked to LC …

Coco-St Detects Global And Local Biological Structures In Spatial Transcriptomics Datasets, Muhammad Aminu, Bo Zhu, Natalie Vokes, Hong Chen, Lingzhi Hong, Jianrong Li, Junya Fujimoto, Mehdi Chaib, Yuqiu Yang, Bo Wang, Alissa Poteete, Monique B Nilsson, Xiuning Le, Tina Cascone, David Jaffray, Nicholas Navin, Tao Wang, Lauren A Byers, Don L Gibbons, John Heymach, Ken Chen, Chao Cheng, Jianjun Zhang, Jia Wu

Faculty, Staff and Students Publications

Spatial domain detection methods often focus on high-variance structures, such as tumour-adjacent regions with sharp gene expression changes, while missing low-variance structures with subtle gene expression shifts, like those between adjacent normal and early adenoma regions. Here, to address this, we introduce ‘compare and contrast spatial transcriptomics’ (CoCo-ST), a graph contrastive feature representation framework. By comparing a target sample with a background sample, CoCo-ST detects both high-variance, broadly shared structures and low-variance, tissue-specific features. It offers technical advantages, including multisample integration, batch-effect correction and scalability across technologies from spot-level Visium data to single-cell Xenium Prime 5K and subcellular Visium HD …

Perfluoroalkyl Substance Pollutants Disrupt Microglia Function And Trigger Transcriptional And Epigenomic Changes, Yating Cheng, Jian-Rong Li, Hangjin Yu, Shuang Li, Boranai Tychhon, Chao Cheng, Yi-Lan Weng

Faculty, Staff and Students Publications

Per- and polyfluoroalkyl substances (PFAS), commonly referred to as "forever chemicals", are widely utilized in various industries and consumer products worldwide. Their exposure has been associated with numerous diseases and malignancies, including neurodevelopmental and neurodegenerative disorders. However, the molecular mechanisms underlying PFAS-induced adverse effects on the central nervous system (CNS) remain poorly understood. In this study, we investigated the transcriptomic and epigenetic changes in microglia exposed to perfluorooctane sulfonate (PFOS), a prevalent PFAS compound. Our findings demonstrate that 24-hour PFOS exposure (25 and 50 µM) disrupts the microglial transcriptome and compromises their homeostatic state, marked by increased inflammation and impaired …

Optic Nerve Injury Impairs Intrinsic Mechanisms Underlying Electrical Activity In A Resilient Retinal Ganglion Cell, Thomas E Zapadka, Nicholas M Tran, Jonathan B Demb

Faculty, Staff and Students Publications

Retinal ganglion cells (RGCs) are the sole output neurons of the retina and convey visual information to the brain via their axons in the optic nerve. Following injury to the optic nerve, RGCs axons degenerate and many cells die. For example, a model of axon injury, the optic nerve crush (ONC), kills ~80% of RGCs after two weeks. Surviving cells are biased towards ‘resilient’ types, including several with sustained firing to light stimulation. RGC survival may depend on activity, and there is limited understanding of how or why activity changes following optic nerve injury. Here we quantified the electrophysiological properties …

Selective Agonism Of Liver And Gut Fxr Prevents Cholestasis And Intestinal Atrophy In Parenterally Fed Neonatal Pigs, Yanjun Jiang, Zhengfeng Fang, Gregory Guthrie, Barbara Stoll, Shaji Chacko, Sen Lin, Bolette Hartmann, Jens J Holst, Harry Dawson, Jose J Pastor, Ignacio R Ipharraguerre, Douglas G Burrin

Faculty, Staff and Students Publications

We aimed to investigate the relative efficacy of feeding different bile acids in preventing PNALD in neonatal pigs. Newborn pigs given total parenteral nutrition (TPN) combined with minimal enteral feeding of chenodeoxycholic acid (CDCA) or increasing doses of obeticholic acid (OCA) for 19 days. Enteral OCA (5 and 15 mg/kg), but not CDCA (30 mg/kg) reduced blood cholestasis markers compared to TPN controls and increased bile acids in the gallbladder and intestine. Major bile acids in the liver and distal intestine were CDCA, HCA, HDCA, and OCA, and their relative proportions were increased by the type of bile acid (CDCA …

Six Drivers Of Aging Identified Among Genes Differentially Expressed With Age, Ariella Coler-Reilly, Zachary Pincus, Erica L Scheller, Roberto Civitelli

2020-Current year OA Pubs

Many studies have compared gene expression in young and old samples to gain insights on aging, the primary risk factor for most chronic diseases. However, these studies only identify associations without distinguishing drivers of aging from compensatory geroprotective responses or incidental downstream effects. Here, we introduce a workflow to characterize causal effects of differentially expressed genes on lifespan. First, we performed a meta-analysis of 25 gene expression datasets comprising samples of various tissues from healthy, untreated adult mammals (humans, dogs, and rodents) at two distinct ages. Genes were ranked by the number of datasets in which they exhibited consistent differential …

Context-Dependent Contribution Of Peptidyl Arginine Deiminase 4 (Pad4) To Neutrophil Extracellular Trap Formation And Liver Injury In Acute And Chronic Hepatotoxicant Challenge, Gina E Capece, Amish K Patel, Daniel Hu, Tayana Roychowdhury, Bianca Hazel, Jessica Kothapalli, Noah A Mac, Frederik Denorme, Robert A Campbell, Lauren G Poole

2020-Current year OA Pubs

Neutrophils play a complex role in the pathogenesis of chronic liver disease and have been linked to both liver damage and injury resolution. Recent reports propose that neutrophils drive liver injury and fibrosis through the formation of neutrophil extracellular traps (NETs). This study tests the hypothesis that the enzyme peptidyl arginine deiminase-4 (PAD4) drives NET formation and liver fibrosis in experimental chronic liver injury. Wild-type (PAD4+/+) and PAD4-deficient (PAD4-/-) mice were chronically challenged twice weekly with carbon tetrachloride (CCl4, 1 ml/kg, i.p) or vehicle (corn oil) for 6 weeks, and samples were collected 24 h after the final challenge. In …

Multiomic And Electrophysiologic Analyses Reveal That An Inherited Mrc2 Variant Causes Fibroblast Dysfunction And Increased Atrial Fibrillation Susceptibility, Kevin S Ho, Joshua A Keefe, Shuai Zhao, Mohit M Hulsurkar, Sung Yun Jung, Md Abul Hassan Samee, Xander H T Wehrens

Faculty, Staff and Students Publications

A recent study identified a rare variant in the mannose receptor C type 2 (MRC2) gene in individuals with familial reentrant supraventricular tachycardia, a Wolff-Parkinson-White (WPW) electrocardiogram pattern, and structurally normal hearts. WPW syndrome is associated with atrial fibrillation (AF), and MRC2 was recently proposed as a protective gene for AF. We determined whether the E990G-heterozygous (het) loss-of-function variant in Mrc2 increases AF susceptibility and identified aberrant cellular mechanisms resulting from Mrc2 deficiency in atrial cardiofibroblasts (ACFs) and atrial tissue in mice that may promote AF. Programmed electrical stimulation was performed to determine AF susceptibility in Mrc2 E990G-het …

Single-Nucleus Mrna-Sequencing Reveals Dynamics Of Lipogenic And Thermogenic Adipocyte Populations In Murine Brown Adipose Tissue In Response To Cold Exposure, Janina Behrens, Tongtong Wang, Christoph Kilian, Anna Worthmann, Mark A Herman, Joerg Heeren, Lorenz Adlung, Ludger Scheja

Faculty, Staff and Students Publications

Objective and methods: Brown adipose tissue (BAT) comprises a heterogeneous population of adipocytes and non-adipocyte cell types. To characterize these cellular subpopulations and their adaptation to cold, we performed single-nucleus mRNA-sequencing (snRNA-seq) on interscapular BAT from mice maintained at room temperature or exposed to acute (24h) or chronic (10 days) cold (6 °C). To investigate the role of the de novo lipogenesis (DNL)-regulating transcription factor carbohydrate response element-binding protein (ChREBP), we analyzed control and brown adipocyte-specific ChREBP knockout mice.

Results: We identified different cell populations, including seven brown adipocyte subtypes with distinct metabolic profiles. One of them highly expressed ChREBP …

Pathogenic Xpo1 Variants Cause A Dominant Neurodevelopmental Disorder, Amber S E Van Oirsouw, Pavla Nedbalova, Miroslava Hancarova, Jan Prchal, Darina Prchalova, Marketa Vlckova, Sarka Bendova, Kristin G Monaghan, Lisa M Dyer, Yanmin Chen, Deanna Alexis Carere, Emma A M Te Bogt, Heather Fisher, Angela E Scheuerle, Stephanie Riley, Mahim Jain, Weiyi Mu, Joann N Bodurtha, Albertien M Van Eerde, Marijn F Stokman, Nicola Longo, Meena Balasubramanian, Michael Spiller, Gregory Costain, Charlotte Von Der Lippe, Kristian Tveten, Marianne Jortveit, Øystein L Holla, Bertrand Isidor, Benjamin Cogné, Kevin E Glinton, Blake Vuocolo, Roberta Ann Sierra, Brad Angle, Kelly Bontempo, Klaas Koop, Rachel Rabin, John Pappas, David A Staffenberg, Pascal Joset, Peter Miny, Isabel Filges, Abdulrazak Alali, Kara Vitalone, Jill A Rosenfeld, Weimin Bi, Samuel Bradbrook, Renee Perrier, Subhadra Ramanathan, June-Anne Gold, María Palomares Bralo, María Ángeles Gómez-Cano, Ann Haskins Olney, Shelly Nielsen, Alban Ziegler, Dominique Bonneau, Clément Prouteau, Ange-Line Bruel, Charlotte Caille-Benigni, Laëtitia Lambert, Andrea C Yu, Nathaniel H Robin, Dana Goodloe, Jan Fischer, Joseph Porrmann, Yvonne D Hennig, Rami Abou Jamra, Isabella Herman, Ivy R Johnson, Lucas Hérissant, Guillaume Jouret, Koen L I Van Gassen, Ellen Van Binsbergen, Bert Van Der Zwaag, Alwin Kamermans, Renske Oegema, Zdenek Sedlacek, Michaela Fenckova, Richard H Van Jaarsveld

Faculty, Staff and Students Publications

Purpose: XPO1 functions in key cellular processes, including nucleo-cytoplasmic export and mitosis. The gene is deleted in a subset of patients with the 2p15p16.1 microdeletion syndrome; however, no monogenic XPO1-related disorder has been described to date.

Methods: We collected clinical data of individuals with de novo XPO1 variants through online matchmaking. We used Drosophila to study XPO1 function in development and habituation learning.

Results: A total of 22 individuals met the criteria to be included in the main study cohort. Of these, half have putative loss-of-function variants, and half have coding variants (10 missense and 1 in-frame deletion variant). We …

Chemical Modulation Of Gut Bacterial Metabolism Induces Colanic Acid And Extends The Lifespan Of Nematode And Mammalian Hosts, Guo Hu, Marzia Savini, Matthew Brandon Cooke, Xin Wei, Dinghuan Deng, Shihong M Gao, Ruyue Alps Xia, Youchen Guan, Alice X Wen, Xin Yu, Jin Wang, Chao Jiang, Christophe Herman, Jiefu Li, Meng C Wang

Faculty, Staff and Students Publications

Microbiota-derived metabolites have emerged as key regulators of longevity. The metabolic activity of the gut microbiota, influenced by dietary components and ingested chemical compounds, profoundly impacts host fitness. While the benefits of dietary prebiotics are well-known, chemically targeting the gut microbiota to enhance host fitness remains largely unexplored. Here, we report a novel chemical approach to induce a pro-longevity bacterial metabolite in the host gut. We discovered that wild-type Escherichia coli strains overproduce colanic acids (CAs) when exposed to a low dose of cephaloridine, leading to an increased life span in the host organism Caenorhabditis elegans. In the mouse gut, …