Medical Sciences Commons^™

Contribution Of Pannexin Channels To Afterimage Signals In The Amphibian Retina, Yufei Liu, Nick Libian, Zheng Jiang, Wen Shen

Faculty, Staff and Students Publications

Pannexin 1 (Panx1) forms large-pore, single-membrane channels that connect the intracellular and extracellular environments, permitting the passage of ions and small molecules such as ATP. Panx1 channels are involved in diverse signaling pathways that contribute to various physiological processes, including sensory processing, although their precise mechanisms of action remain incompletely understood. This study reveals a Panx1-mediated mechanism regulating visual signal processing in the amphibian retina. Using immunolabeling and confocal imaging, we localized Panx1 channels in the cone-dominated On-bipolar cells, specifically at both somas and axon terminals. Whole-cell patch-clamp recordings showed that these channels have high permeability to Cl⁻ ions, which …

Mechanisms Underlying Atrial Fibrillation In Chronic Kidney Disease, Jose Alberto Navarro-Garcia, Joshua A Keefe, Jia Song, Na Li, Xander H T Wehrens

Faculty, Staff and Students Publications

Chronic kidney disease (CKD) is a serious and progressive worldwide health problem affecting 15 % of the global population. CKD is associated with higher mortality rates due to secondary complications such as cardiovascular disease. Common cardiovascular complications found in CKD patients include left ventricular hypertrophy, heart failure, and cardiac arrhythmias. The most common type of cardiac arrhythmia in CKD patients is atrial fibrillation (AF). Proper management of AF is important due to its high risk of cardiovascular complications and stroke. The incidence of AF remains higher in CKD patients than in the healthy population, highlighting the need to improve our …

Sugar Functionalized Collagen Material For Local Modulation Of Innate Immunity, Francesca Taraballi, Claudia Corbo, Julia Enterria-Rosales, John Otto Martinez, Silvia Minardi, Laura Pandolfi, Xing Wang, Ennio Tasciotti, Kavindra V Singh, Cesar A Arias, Bruna Corradetti

Faculty, Staff and Students Publications

Small alterations during the early stages of the innate immune response to an implant can drive large changes in adaptive immunity. Biomaterials for regenerative purposes can be engineered to modulate this immune response in beneficial ways. This study presents an innovative patch designed and functionalized to target the innate immunity at the implant site. Mannose moieties are incorporated into collagen patches, resulting in a technology called Local Immunotuning Patch (LIP), designed to directly interact with antigen presenting cells through their mannose receptor. In vitro, LIP shows anti-inflammatory effects on bone marrow-derived macrophages and inhibitory properties even on methicillin-resistant bacterial strains. …

Sirt5 Inhibition Impairs Mitochondrial Metabolism And Enhances Venetoclax-Induced Elimination Of Acute Myeloid Leukemia Cells, Moran Wang, Ruiqi Zhu, Donald Small, Lan Lin, Li Li, Shengling Ma, Linghui Xia, Shanshan Luo, Wenjuan He, Jianming Yu, Junying Li, Ruowen Wei, Ao Zhang, Wei Shi, Yu Hu

Faculty, Staff and Students Publications

Metabolic reprogramming is a key focus of targeted therapies in acute myeloid leukemia (AML). The mitochondrial sirtuin SIRT5 removes succinyl groups from specific lysines and impacts cell metabolism, but its role in AML tumorigenesis has not been extensively explored. A recent study highlighted that SIRT5 regulates AML cell activity by modulating glutamine metabolism, but its molecular targets in AML remain unclear. This study aims to identify the substrates of SIRT5 in AML. It was found that a total of 83 proteins with 121 lysine (K) residues showed increased succinylation after SIRT5 knockdown, as determined by succinylome analysis of MOLM-13 cells. …

Low-Dose Metformin Requires Brain Rap1 For Its Antidiabetic Action, Hsiao-Yun Lin, Weisheng Lu, Yanlin He, Yukiko Fu, Kentaro Kaneko, Peimeng Huang, Ana B De La Puente-Gomez, Chunmei Wang, Yongjie Yang, Feng Li, Yong Xu, Makoto Fukuda

Faculty, Staff and Students Publications

Metformin is the most commonly prescribed antidiabetes drug, yet its precise mechanism of action remains controversial. Previous studies have suggested that metformin acts peripherally by reducing hepatic glucose output and altering gut functions. Here, we report a neural mechanism via the small guanosine triphosphatase Ras-related protein 1 (Rap1). Mice with forebrain-specific Rap1 knockout exhibited resistance to the antidiabetic effects of low-dose metformin while remaining sensitive to other antidiabetic agents. Centrally administered metformin inhibited brain Rap1 and reduced hyperglycemia. Conversely, forced activation of brain Rap1 increased glycemia and abolished the glycemic effect of metformin. Metformin activated a specific subset of neurons …

The Glycosyltransferase Poglut1 Regulates Muscle Stem Cell Development And Maintenance In Mice, Soomin Cho, Emilia Servián-Morilla, Victoria Navarro, Beatriz Rodriguez-Gonzalez, Youxi Yuan, Raquel Cano, Arjun A Rambhiya, Radbod Darabi, Robert S Haltiwanger, Carmen Paradas, Hamed Jafar-Nejad

Faculty, Staff and Students Publications

Mutations in protein O-glucosyltransferase 1 (POGLUT1) cause a recessive limb-girdle muscular dystrophy (LGMDR21) with reduced satellite cell number and NOTCH1 signaling in adult patient muscles and impaired myogenic capacity of patient-derived muscle progenitors. However, the in vivo roles of POGLUT1 in the development, function, and maintenance of satellite cells are not well understood. Here, we show that conditional deletion of mouse Poglut1 in myogenic progenitors leads to early lethality, postnatal muscle growth defects, reduced Pax7 expression, abnormality in muscle extracellular matrix, and impaired muscle repair. Poglut1-deficient muscle progenitors exhibit reduced proliferation, enhanced differentiation, and accelerated fusion into myofibers. Inducible loss …

Mx1-Labeled Pulp Progenitor Cells Are The Main Contributors Of Odontoblast And Dentin Regeneration In Murine Molars, Dongwook Yang, Youngjae Jeong, Laura Ortinau, Jea Giezl Solidum, Dongsu Park

Faculty, Staff and Students Publications

Regeneration of dentin and odontoblasts from dental pulp progenitor cells is essential for the maintenance of permanent tooth. However, the in vivo identity of endogenous pulp progenitor cells and how they contribute to reparative dentinogenesis remain elusive. Here we show that comparative single-cell analysis of pulp cells before and after molar eruption reveal that endogenous pulp progenitor cells are enriched in coronal papilla-like cells with Mx1-Cre and Cxcl12–GFP expression. Further, lineage tracing and fluorescence-activated cell sorting analysis indicated that Mx1-labeled (Mx1+) pulp cells include long-term repopulating progenitor cells with higher expression of stem cell markers. Notably, …

Comparative Efficacy Of Current Topical Treatments For Dry Eye Disease: A Review Of Pivotal Clinical Trials Evaluating Corneal Staining Outcomes, Ahmad Fahmy, Masih Ahmed, Stephen Pflugfelder, Anara Serikbaeva, Fang-Wei Tsao

Faculty, Staff and Students Publications

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Crispr-Cas9 Engineering Of Human T Regulatory Cells – Design And Optimization Of A Manufacturing Process, Ortal Shimon, Adam M Dean, Shoshana Cohen, Aiden L Moser, Clifford C Dacso, Yosi Gilad, David M Lonard, Bert W O'Malley

Faculty, Staff and Students Publications

Regulatory T cells (Tregs) are a subset of CD4 + T cells that comprise 5-10 % of the total CD4 + T cell population. Tregs, which are critically important for the maintenance of immune tolerance and immune homeostasis, are distinguished from other subtypes of CD4 + T cells by the expression of the transcription factor FOXP3. Because of the centrality to immunoregulation, Tregs have gained increasing attention as promising targets for clinical applications in autoimmune diseases, transplant rejection and graft-versus-host disease (GvHD). However, the essential role of Tregs in the complex network of the immune system implies their targeting as …

The Synaptic Architecture Of Layer 5 Thick Tufted Excitatory Neurons In Mouse Visual Cortex, Agnes L Bodor, Casey M Schneider-Mizell, Chi Zhang, Leila Elabbady, Alex Mallen, Andi Bergeson, Derrick Brittain, Joann Buchanan, Daniel J Bumbarger, Rachel Dalley, Clare Gamlin, Emily Joyce, Daniel Kapner, Sam Kinn, Gayathri Mahalingam, Sharmishtaa Seshamani, Shelby Suckow, Marc Takeno, Russel Torres, Wenjing Yin, J Alexander Bae, Manuel A Castro, Sven Dorkenwald, Akhilesh Halageri, Zhen Jia, Chris Jordan, Nico Kemnitz, Kisuk Lee, Kai Li, Ran Lu, Thomas Macrina, Eric Mitchell, Shanka Subhra Mondal, Shang Mu, Barak Nehoran, Sergiy Popovych, William Silversmith, Nicholas L Turner, Szi-Chieh Yu, William Wong, Jingpeng Wu, Brendan Celii, Luke Campagnola, Stephanie C Seeman, Tim Jarsky, Naixin Ren, Anton Arkhipov, Jacob Reimer, H Sebastian Seung, R Clay Reid, Forrest Collman, Nuno Maçarico Da Costa

Faculty, Staff and Students Publications

Despite significant progress in characterizing neocortical cell types, a complete understanding of the synaptic connections of individual excitatory cells remains elusive. This study investigates the connectivity of mouse visual cortex thick tufted layer 5 pyramidal cells, also known as extratelencephalic neurons (L5-ETns), using a 1 mm3 publicly available electron microscopy dataset. The analysis reveals that, in their immediate vicinity, L5-ETns primarily establish connections with a group of inhibitory cell types, which, in turn, specifically target the L5-ETns back. The most common excitatory targets of L5-ETns are layer 5 intertelencephalic neurons (L5-ITns) and layer 6 (L6) pyramidal cells, whereas synapses with …

N-Acetylaspartate From Fat Cells Regulates Postprandial Body Temperature, Jessica B Felix, Pradip K Saha, Evelyn L De Groot, Lin Tan, Robert Sharp, Elizabeth S Anaya, Yafang Li, Holly Quang, Nooshin Saidi, Layla Abushamat, Christie M Ballantyne, Christopher I Amos, Philip L Lorenzi, Samuel Klein, Xia Gao, Sean M Hartig

Faculty, Staff and Students Publications

N-acetylaspartate (NAA), the brain’s second most abundant metabolite, provides essential substrates for myelination through its hydrolysis1. However, the physiological roles of NAA in other tissues remain unknown. Here, we show that aspartoacylase (ASPA) expression in white adipose tissue (WAT) governs blood NAA levels for postprandial body temperature regulation. Genetic ablation of Aspa in mice resulted in systemically elevated NAA levels, and the ensuing accumulation in WAT stimulated pyrimidine production. Stable isotope tracing confirmed higher incorporation of glucose-derived carbon into pyrimidine metabolites in Aspa knockout cells. Additionally, serum NAA levels positively correlated with the abundance of the pyrimidine …

Nanotechnology For Immuno-Oncology, Adam J Grippin, Daeyong Lee, Eileen E Parkes, Wen Jiang, Betty Y S Kim

Faculty, Staff and Student Publications

Although the first generation of cancer immunotherapeutics produced unprecedented improvements in clinical outcomes for individuals with cancer, novel strategies to increase treatment specificity, delivery efficiency and pharmacokinetics are still needed. In this Review, we describe the potential advantages and current limitations of nanomaterials for cancer immunotherapy and highlight rational uses of nanosystems to generate potent and durable antitumor immune responses. We close with a review of the current state of clinical development of nanomedicine for cancer immunotherapy.

Evolution Of Esophageal Adenocarcinoma From Precursor Lesion Stem Cells, Wa Xian, Shan Wang, Jingzhong Xie, Yusuke Yamamoto, Melina Khorrami, Yanting Zhang, Raul Caballero Montes, Caycel Desales, Melika Khorrami, Zaal Mory, Ashley Hoffman, Amber Su, Crystal Nguyen, Peter J A Davies, Clifford Stephan, Shuang Pan, Wengen Wu, Yuxin Liu, Jeremy Siegelman, Rebecca E Waters, William A Ross, Shumei Song, Mark Metersky, David G Beer, Christopher P Crum, Alexander J Stewart, Matthew Vincent, Richard Russell, Robert A Izard, Khek Yu Ho, Jack Hung-Sen Lai, William W Bachovchin, Jaffer A Ajani, Frank D Mckeon

Faculty, Staff and Student Publications

Background & aims: Metastatic cancers arise from a decades-long succession of increasingly virulent precursor lesions, each of which represents prospective targets for therapeutic intervention. This evolutionary process has been particularly vivid in esophageal adenocarcinoma (EAC), as this cancer and associated precursor lesions, including Barrett's esophagus (BE), low-grade dysplasia (LGD), and high-grade dysplasia (HGD), coexist in an accessible, 2-dimensional pattern in esophageal mucosa. Given the durability of these precursor lesions, it is likely that they, like EAC, rely on stem cells for their regenerative growth. To assess the role of stem cells in the evolution of EAC, we apply technology that …

12/15-Lipooxygenase Inhibition Reduces Microvessel Constriction And Microthrombi After Subarachnoid Hemorrhage In Mice, Ari Dienel, Sung Ha Hong, Hussein A Zeineddine, Sithara Thomas, Shafeeque C M, Dania A Jose, Kiara Torres, Jose Guzman, Andrew Dunn, P Kumar T, Gadiparthi N Rao, Spiros L Blackburn, Devin W Mcbride

Faculty, Staff and Student Publications

Impaired cerebral circulation, induced by blood vessel constrictions and microthrombi, leads to delayed cerebral ischemia after subarachnoid hemorrhage (SAH). 12/15-Lipooxygenase (12/15-LOX) overexpression has been implicated in worsening early brain injury outcomes following SAH. However, it is unknown if 12/15-LOX is important in delayed pathophysiological events after SAH. Since 12/15-LOX produces metabolites that induce inflammation and vasoconstriction, we hypothesized that 12/15-LOX leads to microvessel constriction and microthrombi formation after SAH, and thus, 12/15-LOX is an important target to prevent delayed cerebral ischemia. SAH was induced in C57BL/6 and 12/15-LOX−/− mice of both sexes by endovascular perforation. Expression of 12/15-LOX was assessed …

Mitophagy’S Impacts On Cancer And Neurodegenerative Diseases: Implications For Future Therapies, Jason Huang, Vincent Truong Pham, Shaozi Fu, Gang Huang, Ya-Guang Liu, Lei Zheng

Faculty, Staff and Student Publications

Substantial evidence supports an inverse relationship between cancer and neurodegenerative diseases (NDDs), but few studies investigate the biological mechanisms underlying this phenomenon. While previous explanations-such as inflammation, reactive oxygen species (ROS), genetic mutations, and cell death-remain significant, they ultimately converge on mitophagy. This review identifies mitophagy as a pivotal factor in the development of both cancer and NDDs, while also evaluating specific mechanisms and processes to clarify how mitophagy connects these opposing disease trajectories. By examining these factors, we aim to uncover the underlying mechanisms that explain the inverse relationship between cancer and NDDs, which will help develop therapeutic strategies …

Gd3 Synthase Drives Resistance To P53-Induced Apoptosis In Breast Cancer By Modulating Mitochondrial Function, Vivek Anand, Fouad El-Dana, Natalia Baran, Jenny Borgman, Zheng Yin, Hong Zhao, Stephen T Wong, Michael Andreeff, V Lokesh Battula

Faculty, Staff and Student Publications

TP53 mutations are common in breast cancer (BC) and are associated with poor prognosis. GD3 synthase (GD3S/ST8SIA1), a gene associated with breast cancer stem cells, is upregulated in tumors with p53 mutations. However, the functional relationship between GD3S and p53 is unknown. Here, we show that GD3S levels are highest in breast tumors with specific p53 mutations. Functional studies revealed that wild-type (WT) p53 inhibits GD3S expression, whereas mutation in p53 enhances GD3S expression by upregulating GD3S promoter activity. Moreover, we found that GD3S inhibits wild-type p53-induced apoptosis in BC cells, while BC cells harboring gain-of-function p53 mutations are dependent …

Inhibition Of Methylthioadenosine Phosphorylase Protects From Experimental Acute Kidney Injury, Afaf Saliba, Yidong Chen, Jonathan W Nelson, Abhinav Vetcha, Wei Wei Wang, Li Kang, Nagarjunachary Ragi, Soumya Maity, Hamid Rabb, W Brian Reeves, Kumar Sharma

Faculty, Staff and Student Publications

Methylthioadenosine phosphorylase (MTAP) is a key enzyme in purine metabolism that may influence cellular responses to injury. We evaluated the effects of prophylactic MTAP inhibition in mouse models of ischemia-reperfusion and cisplatin-induced acute kidney injury (AKI). MTAP inhibition was confirmed by accumulation of methylthioadenosine (MTA). Treated mice showed reduced renal injury and decreased tubular damage. Transcriptomic analysis revealed protection from inflammatory and stress pathways, while maintaining oxidative phosphorylation, fatty acid metabolism, and epithelial integrity-related genes. Analysis of human single-cell RNA-seq data from the Kidney Precision Medicine Project indicated that MTAP is highly expressed in kidney injury marker-positive adaptive proximal tubule …

Human And Mouse Alzheimer's Seeds Differentially Affect Amyloid Deposition And Microglia-Dependent Plaque Response In Aged Mice, Juana Andreo-Lopez, Cristina Nuñez-Diaz, Kelly Do Huynh, Marie Minh Thu Nguyen, Celia Da Cunha, Francisco J Cantero-Molina, Cynthia Campos-Moreno, Stefania Zimbone, Francesco Bellia, Maria Laura Giuffrida, Laura Trujillo-Estrada, Juan Antonio Garcia-Leon, Miriam Bettinetti-Luque, Nazaret Gamez, Catalina Valdes, Rodrigo Morales, Stefania Forner, Alessandra C Martini, Antonia Gutierrez, Frank M Laferla, David Baglietto-Vargas

Faculty, Staff and Student Publications

Alzheimer's disease (AD) is a complex neurodegenerative proteinopathy in which Aβ and tau misfold and aggregate into entities that structurally unsettle native proteins, mimicking a prion-like or "seeding" process. These Aβ and tau "seeds" can arrange in different conformations or strains that might display distinct pathogenic properties. Furthermore, recent evidence suggests that microglia play a key role in the amyloidogenic event and can modulate the propagation and aggregation processes. Here, we employed histological and molecular approaches to determine whether seeds from human AD brains compared to those from transgenic mice (3xTg-AD) are more prone to induce Aβ and tau aggregates …

Orp2 Regulates Free Cholesterol Accumulation In Hepatocytes During Mash, Jin Wu, Yudi Zhao, Liwen Qiu, Qiaoli Chen, Xiaowei Wang, Jingwen Gu, Yan Liang, Yingjie Zhang, Hong-Yu Wang, Yang Liu, Xiaoqin Wu, Shuai Chen, Feng-Jung Chen, Mingming Gao, Hongyuan Yang

Faculty, Staff and Student Publications

Background: Cholesterol crystals in hepatocytes are known to strongly associate with human metabolic dysfunction-associated steatohepatitis. However, it remains unclear which molecular pathway(s) regulates free cholesterol accumulation and the formation of cholesterol crystals in hepatocytes. In cultured cell lines, oxysterol-binding protein-related protein 2 (ORP2) functions to deliver cholesterol to the plasma membrane from endosomal compartments.

Methods: Here, we generated liver-specific ORP2 knockout (ORP2-LKO) mice and characterized their metabolic phenotypes on chow and high-fat diet.

Results: The ORP2-LKO mice developed much more severe hepatic steatosis than floxed control mice after high-fat diet feeding. They also demonstrated more severe liver inflammation and damage. …

Acquired Resistance In Cancer: Towards Targeted Therapeutic Strategies, Alice Soragni, Erik S Knudsen, Thomas N O'Connor, Cristina E Tognon, Jeffrey W Tyner, Beatrice Gini, Donghwa Kim, Trever G Bivona, Xingxing Zang, Agnieszka K Witkiewicz, David W Goodrich, Dadi Jiang, Seth T Gammon, Christopher D Willey, Paul C Boutros, Vlad C Sandulache, Abdullah A Osman, Jeffrey N Myers, Kamiya Mehla, Pankaj K Singh, Keith S Chan, Hongbo Gao, Himangi Marathe

Faculty, Staff and Student Publications

Development of acquired therapeutic resistance limits the efficacy of cancer treatments and accounts for therapeutic failure in most patients. How resistance arises, varies across cancer types and differs depending on therapeutic modalities is incompletely understood. Novel strategies that address and overcome the various and complex resistance mechanisms necessitate a deep understanding of the underlying dynamics. We are at a crucial time when innovative technologies applied to patient-relevant tumour models have the potential to bridge the gap between fundamental research into mechanisms and timing of acquired resistance and clinical applications that translate these findings into actionable strategies to extend therapy efficacy. …

Nerve-To-Cancer Transfer Of Mitochondria During Cancer Metastasis, Gregory Hoover, Shila Gilbert, Olivia Curley, Clémence Obellianne, Mike T Lin, William Hixson, Terry W Pierce, Joel F Andrews, Mikhail F Alexeyev, Yi Ding, Ping Bu, Fariba Behbod, Daniel Medina, Jeffrey T Chang, Gustavo Ayala, Simon Grelet

Faculty, Staff and Students Publications

The nervous system has a pivotal role in cancer biology, and pathological investigations have linked intratumoural nerve density to metastasis1. However, the precise impact of cancer-associated neurons and the communication channels at the nerve–cancer interface remain poorly understood. Previous cancer denervation models in rodents and humans have highlighted robust cancer dependency on nerves, but the underlying mechanisms that drive nerve-mediated cancer aggressivity remain unknown2,3. Here we show that cancer-associated neurons enhance cancer metabolic plasticity by transferring mitochondria to cancer cells. Breast cancer denervation and nerve–cancer coculture models confirmed that neurons significantly improve tumour energetics. …

Folliculin Depletion Results In Liver Cell Damage And Cholangiocarcinoma Through Mit/Tfe Activation, Bruno Maria Custode, Francesco Annunziata, Felipe Dos Santos Matos, Valentina Schiano, Veronica Maffia, Milena Lillo, Rita Colonna, Rossella De Cegli, Andrea Ballabio, Nunzia Pastore

Duncan NRI Faculty and Staff Publications

Mutations in the tumor suppressor gene Folliculin (FLCN) are responsible for Birt-Hogg-Dube’ (BHD) syndrome, a rare inherited condition that predisposes affected individuals to skin tumors, pulmonary cysts, and kidney tumors. FLCN regulates key cellular pathways, including TFEB, TFE3, and mTORC1, which are critical for maintaining cell homeostasis. Loss of FLCN leads to both hyperactivation of mTORC1 and constitutive activation of TFEB and TFE3, contributing to tumorigenesis. While previous studies showed that Flcn liver-specific conditional knockout (FlcnLiKO) mice are protected from developing liver fibrosis and damage upon high-fat diet exposure, the potential role of FLCN loss in liver carcinogenesis …

De Novo And Inherited Variants In Ddx39b Cause A Novel Neurodevelopmental Syndrome, Kevin T A Booth, Sharayu V Jangam, Martin M C Chui, Kayla Treat, Lorenzo Graziani, Alessia Soldano, Yao Ruan, Jeffrey Wan-Hei Hui, Kerry White, Celanie K Christensen, Ty Lynnes, Shinya Yamamoto, Oguz Kanca, Mandy H Y Tsang, Sally A Lynch, Sureni V Mullegama, Julia Baptista, Daniela Iancu, Shelagh K Joss, Sandra Y Y Wong, Christopher C Y Mak, Anna K Y Kwong, Hugo J Bellen, Erin Conboy, Remo Sanges, Anskar Yu-Hung Leung, Michael F Wangler, Brian H Y Chung, Francesco Vetrini

Duncan NRI Faculty and Staff Publications

DDX39B is a conserved member of the DEAD-box family of ATP-dependent RNA helicases, critical in mRNA metabolism across eukaryotes. DDX39B is also a core component of the TRanscription-EXport (TREX) super protein complex, and recent studies have highlighted the important role of its subunits in neurodevelopmental disorders. Here, we describe six individuals from five families, four harbouring de novo missense variants in DDX39B and one with an inherited splicing variant, presenting with variable developmental delay, congenital hypotonia, epilepsy, short stature, skeletal abnormalities, dysmorphic features and microcephaly in three patients.

3D molecular modelling predicts these variants would alter protein structure. In vitro …

Rapid Dissection And Dissociation Of The Mouse Olfactory Epithelium For Single-Nucleus Suspensions, Benjamin D W Belfort, Anthony M Insalaco, Claude C Chew, Johnathan D Jia, Julia Younis, Benjamin R Arenkiel

Duncan NRI Faculty and Staff Publications

The murine olfactory epithelium is the initial entry point of the olfactory system, housing various cell types that include olfactory sensory neurons, their regenerating progenitors, and support cells. Olfactory sensory neurons transduce chemical odorants into neural signals, yet the mechanisms underlying how these cells develop and turnover, create synapses with the olfactory bulb, and regulate their odorant receptors remain areas of intense study. Located on the dorsal aspect of the nasal cavity, the olfactory epithelium adheres to intricate bony structures known as turbinates. This anatomy poses unique challenges for its extraction and dissociation, especially in the context of preparing viable …

Cd45 And Cd148 Are Critically Involved In Neutrophil Recruitment And Function During Inflammatory Arthritis In Mice, Jan-Niklas Heming, Andreas Margraf, Karolina Najder, Giulia Germena, Mathis Richter, Anika Cappenberg, Katharina Henke, Bernadette Bardel, Lena Schemmelmann, Marina Oguama, Pia Lindental, Wida Amini, Jacqueline Sobocik, Georg Schett, Gerhard Krönke, Helena Block, Jan Rossaint, Oliver Soehnlein, Alexander Zarbock

Faculty, Staff and Student Publications

Neutrophils play a key role in autoimmune diseases like rheumatoid arthritis, contributing to tissue damage through rapid recruitment and activation. In this study, we investigated the regulatory properties of two receptor-like tyrosine phosphatases (RPTPs), CD45 and CD148, in inflammatory arthritis. Using an in vivo mouse model of K/BxN serum transfer-induced arthritis, we found that CD45 and CD148 feature distinct regulatory properties during inflammatory arthritis. CD45 is required for neutrophil infiltration, cytokine release, and reactive oxygen species production, whereas CD148 deficiency leads to a delayed onset of arthritis but unaltered overall neutrophil infiltration and reduced ROS production. Furthermore, we could demonstrate …

Sleep Drive, Not Total Sleep Amount, Increases Seizure Risk, Vishnu Anand Cuddapah, Cynthia T Hsu, Fernanda Valle Sirias, Yongjun Li, Hrishit M Shah, Christopher Saul, Samantha Killiany, Camilo Guevara, Joy Shon, Zhifeng Yue, Gabrielle L Gionet, Mary E Putt, Amita Sehgal

Duncan NRI Faculty and Staff Publications

Sleep loss has been associated with increased seizure risk since antiquity. Using automated video detection of spontaneous seizures in Drosophila epilepsy models, we show that seizures worsen only when sleep restriction raises homeostatic "sleep drive," not simply when total sleep amount falls. This is supported by the paradoxical finding that acute activation of sleep-promoting circuits worsens seizures, because it increases sleep drive without changing sleep amount. Sleep-promoting circuits become hyperactive after sleep loss and are associated with increased whole-brain activity. During sleep restriction, optogenetic inhibition of sleep-promoting circuits to reduce sleep drive protects against seizures. Downregulation of the 5HT1A serotonin …

Phosphoglycerate Mutase Regulates Treg Differentiation Through Control Of Serine Synthesis And One-Carbon Metabolism, Wesley H Godfrey, Judy J Lee, Shruthi Shanmukha, Kaho Cho, Xiaojing Deng, Chandra Shekar R Ambati, Vasanta Putluri, Abu Hena Mostafa Kamal, Paul M Kim, Nagireddy Putluri, Michael D Kornberg

Faculty, Staff and Students Publications

The differentiation and suppressive functions of regulatory CD4 T cells (Tregs) are supported by a broad array of metabolic changes, providing potential therapeutic targets for immune modulation. In this study, we focused on the regulatory role of glycolytic enzymes in Tregs and identified phosphoglycerate mutase (PGAM) as being differentially overexpressed in Tregs and associated with a highly suppressive phenotype. Pharmacologic or genetic inhibition of PGAM reduced Treg differentiation and suppressive function while reciprocally inducing markers of a pro-inflammatory, T helper 17 (Th17)-like state. The regulatory role of PGAM was dependent on the contribution of 3-phosphoglycerate (3 PG), the PGAM substrate, …

Melanoma Antigens In Pediatric Medulloblastoma Contribute To Tumor Heterogeneity And Species-Specificity Of Group 3 Tumors, Rebecca R J Collins, Rebecca R Florke Gee, Sima Tozandehjani, Tara Bayat, Maria Camila Hoyos Sanchez, Juan Sebastian Solano Gutierrez, Barbara Breznik, Anna K Lee, Samuel T Peters, Jon P Connelly, Shondra M Pruett-Miller, Martine F Roussel, Dinesh Rakheja, Heather S Tillman, Patrick Ryan Potts, Klementina Fon Tacer

Faculty, Staff and Student Publications

Medulloblastoma (MB) is the most malignant childhood brain cancer. Group 3 MB (G3 MB) subtype accounts for about 25% of MB and is associated with the worst outcomes. Herein, we report that more than half of G3 MB tumors express melanoma antigens (MAGEs), which are potential prognostic and therapeutic markers. MAGEs are cancer-testis antigens, aberrantly expressed in several adult cancers, and associated with poorer prognosis and therapy resistance; however, their role in pediatric cancers is mostly unknown. This study aimed to determine whether MAGEs are activated and important in pediatric MB. We obtained formalin-fixed paraffin-embedded tumor samples of 34 patients, …

Dietary Lipids Induce Ppard And Bcl6 To Repress Macrophage Il-23 Induction After Intestinal Injury And Lps Exposure, Ashleigh M Gil, Daniel F Zegarra-Ruiz, Wan-Jung Wu, Kendra Norwood, Adrien Assie, Buck S Samuel, Angela M Major, Gretchen E Diehl, Andrea A Hill Mcalester

Faculty, Staff and Students Publications

Unresolved tissue damage is a common feature of Inflammatory Bowel Disease (IBD) that facilitates disease progression. Here, we showed that high animal fat diets (HFD), an environmental risk factor associated with IBD pathogenesis, suppress intestinal macrophage production of critical tissue repair responses after damage. This includes reduced IL-23 production, which drives downstream production of IL-22, which is needed for barrier repair. Indicating that dietary lipids interfere with responses to microbial molecules needed to induce barrier protective functions, we found oleic acid could directly suppress macrophage Il23a induction after lipopolysaccharide (LPS) treatment. Deleting the lipid transporter CD36 on macrophages restored the …

Human Ipsc-Based Breast Cancer Model Identifies S100p-Dependent Cancer Stemness Induced By Brca1 Mutation, Jingxin Liu, Cai Zhao, Jiahao Chen, Pengguihang Zeng, Qingjian Li, Ranran Dai, Xingqiang Lai, Wenqian Song, Jianing Chen, Xixi Zhu, Xinyi Liu, Jun Sun, Jia Wang, Peihang Fang, Tengfei Wang, Wenjie Chen, Diana Guallar, Nan Cao, Jianli Zhao, Shicheng Su, Andy Peng Xiang, Yi Arial Zeng, Jie Li, Junchao Cai, Dung-Fang Lee, Jinxin Bei, Yongliang Huo, Hai Hu, Shengbao Suo, Dong-Feng Huang, Jin Bai, Junjun Ding

Faculty, Staff and Student Publications

Breast cancer is the most common malignancy in females and remains the leading cause of cancer-related deaths for women worldwide. The cellular and molecular basis of breast tumorigenesis is not completely understood partly due to the lack of human research models which simulate the development of breast cancer. Here, we developed a method for generating functional mammary-like cells (MCs) from human-induced pluripotent stem cells (iPSCs). The iPSC-MCs closely resemble human primary MCs at cellular, transcriptional, and functional levels. Using this method, a breast cancer model was generated using patient-derived iPSCs harboring germline