Medical Sciences Commons^™

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 …

Preclinical Fluorescence-Guided Imaging Leveraging Surrounding Sentinel Tumor Microenvironment Identifies High-Risk Premalignant Pancreatic Lesions, Shilpa Sharma, Xiaoxia Wen, Jianbo Wang, Beibei Huang, Denise A Hernandez, Cong-Dat Pham, Zhiwen Liu, Susanne Je-Han Lin, Aiko Yamaguchi, Dimitra K Georgiou, Ryan P Coll, H Charles Manning

Faculty, Staff and Student Publications

Purpose: Because surgery is the only potential cure for pancreatic cancer, high-risk premalignant pancreatic lesions often evade detection by palpation or white-light visualization, increasing the risk of recurrence. We asked whether near-infrared fluorescence imaging of tumor-associated inflammation could identify high-risk premalignant lesions, leveraging the tumor microenvironment as a sentinel of local disease and, thus, enhance surgery outcomes.

Experimental design: Fluorescence-guided surgery was performed on genetically engineered mice [Ptf1a-Cre; LSL-KrasG12D/+; Smad4flox/flox (KSC)] at discrete stages of disease progression, histologically confirmed high-risk, premalignant lesions in postnatal mice to locally advanced pancreatic tumors in adults, using the imaging agent V-1520, a translocator protein …

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 …

Mutations In The Key Autophagy Tethering Factor Epg5 Link Neurodevelopmental And Neurodegenerative Disorders Including Early-Onset Parkinsonism, Hormos Salimi Dafsari, Celine Deneubourg, Kritarth Singh, Reza Maroofian, Zita Suprenant, Ay Lin Kho, Neil J Ingham, Karen P Steel, Preethi Sheshadri, Franciska Baur, Lea Hentrich, Birgit Gerisch, Mina Zamani, Cesar Alves, Ata Siddiqui, Haidar S Dafsari, Mehri Salari, Anthony E Lang, Michael Harris, Alice Abdelaleem, Saeid Sadeghian, Reza Azizimalamiri, Hamid Galehdari, Gholamreza Shariati, Alireza Sedaghat, Jawaher Zeighami, Daniel Calame, Dana Marafi, Ruizhi Duan, Adrian Boehnke, Gary D Clark, Jill A Rosenfeld, Carrie A Mohila, Dora Steel, Saurabh Chopra, Suvasini Sharma, Nicolai Kohlschmidt, Steffi Patzer, Afshin Saffari, Darius Ebrahimi-Fakhari, Büşra Eser Çavdartepe, Irene J Chang, Erika Beckman, Renate Peters, Andrew Paul Fennell, Bernice Lo, Luisa Averdunk, Felix Distelmaier, Martina Baethmann, Frances Elmslie, Kairit Joost, Sheela Nampoothiri, Dhanya Yesodharan, Hanna Mandel, Amy Kimball, Antonie D Kline, Cyril Mignot, Boris Keren, Vincent Laugel, Katrin Õunap, Kalpana Devadathan, Frederique M C Van Berkestijn, Arpana Silwal, Saskia Koene, Sumit Verma, Mohammed Yousuf Karim, Chahynez Boubidi, Majid Aziz, Gehad Elghazali, Lauren Mattas, Mohammad Miryounesi, Farzad Hashemi-Gorji, Shahryar Alavi, Nayereh Nouri, Mehrdad Noruzinia, Saeideh Kavousi, Arveen Kamath, Sandeep Jayawant, Russell Saneto, Nourelhoda A Haridy, Pinar Ozkan Kart, Ali Cansu, Madeleine Joubert, Claire Beneteau, Kyra E Stuurman, Martina Wilke, Tahsin Stefan Barakat, Homa Tajsharghi, Annarita Scardamaglia, Sadeq Vallian, Semra Hız, Ali Shoeibi, Reza Boostani, Narges Hashemi, Meisam Babaei, Norah Saleh Alsaleh, Julie Porter, Tania Attié-Bitach, Pauline Marzin, Dorota Wicher, Jessica I Gold, Elisabeth Schuler, Amna Kashgari, Rakan F Alanazi, Wafaa Eyaid, Marc Engelen, Mirjam Langeveld, Burkhard Stüve, Yun Li, Gökhan Yigit, Bernd Wollnik, Mariana H G Monje, Dimitri Krainc, Niccolò E Mencacci, Somayeh Bakhtiari, Michael Kruer, Emanuela Argilli, Elliott Sherr, Yalda Jamshidi, Ehsan Ghayoor Karimiani, Yiu Wing Sunny Cheung, Ivan Karin, Giovanni Zifarelli, Peter Bauer, Wendy K Chung, James R Lupski, Manju A Kurian, Jörg Dötsch, Jürgen-Christoph Von Kleist-Retzow, Thomas Klopstock, Matias Wagner, Calvin Yip, Andreas Roos, Rita Carsetti, Carlo Dionisi-Vici, Mathias Gautel, Michael R Duchen, Adam Antebi, Henry Houlden, Manolis Fanto, Heinz Jungbluth

Faculty, Staff and Students Publications

Objective: Autophagy is a fundamental biological pathway with vital roles in intracellular homeostasis. During autophagy, defective cargoes including mitochondria are targeted to lysosomes for clearance and recycling. Recessive truncating variants in the autophagy gene EPG5 have been associated with Vici syndrome, a severe early-onset neurodevelopmental disorder with extensive multisystem involvement. Here, we aimed to delineate the extended, age-dependent EPG5-related disease spectrum.

Methods: We investigated clinical, radiological, and molecular features from the largest cohort of EPG5-related patients identified to date, complemented by experimental investigation of cellular and animal models of EPG5 defects.

Results: Through worldwide collaboration, we identified 211 patients, 97 …

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 …

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 …

Leptin As A Key Driver For Organ Fibrogenesis, Xue-Nan Sun, Shiuhwei Chen, Shangang Zhao, Jan-Bernd Funcke, Megan Virostek, Line Pedersen, Chao Li, Chanmin Joung, Qian Lin, Yan Li, Ayanna Cobb, May-Yun Wang, Kyounghee Min, Lisandro Maya-Ramos, Giovanna Degasperi, Junquan Liu, Ningyan Zhang, Zhiqiang An, Diana R Tomchick, R Max Wynn, Da Young Oh, Philipp E Scherer

Faculty, Staff and Student Publications

Leptin, a hormone primarily secreted by adipocytes, regulates energy balance and systemic metabolism through its interaction with the leptin receptor (LEPR). Beyond these functions, leptin signaling has been implicated in the pathogenesis of tissue fibrosis. Here, we report the x-ray crystal structures of a leptin-neutralizing antibody (hLep3) in the unbound and leptin-bound states. The interaction of this antibody with leptin mimics the interaction of the LEPR with leptin, providing direct insights into the mechanism by which the antibody disrupts leptin signaling. We furthermore evaluate the therapeutic potential of neutralizing leptin with this antibody across distinct mouse models of fibrosis affecting …

Sperm And Offspring Production In A Nonobstructive Azoospermia Mouse Model Via Testicular Mrna Delivery Using Lipid Nanoparticles, Daisuke Mashiko, Chihiro Emori, Yuki Hatanaka, Daisuke Motooka, Chen Pan, Yuki Kaneda, Martin M Matzuk, Masahito Ikawa

Faculty, Staff and Students Publications

Microsurgical testicular sperm extraction (microTESE) with intracytoplasmic sperm injection (ICSI) represents the current standard treatment for nonobstructive azoospermia (NOA). However, cures remain unavailable for NOA patients lacking retrievable haploid cells. mRNA supplementation could be a potential treatment for genetic defects leading to impaired spermatogenesis. Lipid nanoparticles (LNPs) have emerged as mRNA delivery vehicles with minimal risk of genome integration; however, their ability to selectively deliver mRNA to specific cell types remains limited. To overcome this, microRNA (miRNA) target sequences were incorporated into mRNA constructs to restrict expression specifically to germ cells. Using pyruvate dehydrogenase E1 subunit alpha 2 (PDHA2) knockout …

Polychlorinated Biphenyls Alter Estrogen Receptor Β-Mediated Epigenetic Regulation, Promoting Endometriosis, Yuri Park, Nuri Sung, Eunsu Kim, Jaeyeong Jeong, Juhee Sim, Mi Jin Park, John P Lydon, Xiaoming Guan, Sang Jun Han

Faculty, Staff and Students Publications

Endometriosis is a pathological condition characterized by the ectopic growth of endometrial cells, leading to chronic pelvic pain and infertility. Epidemiological studies have associated exposure to dioxin-like polychlorinated biphenyls, particularly PCB126, with an increased risk of endometriosis. However, the underlying mechanisms of this association remain poorly understood. We utilized a surgically induced endometriosis mouse model and human endometrial cell lines to assess the impact of PCB126 on endometriosis progression. Mice were exposed to environmentally relevant doses of PCB126. Endometriotic lesion growth, estrogen receptor signaling, receptor tyrosine kinase activity, and gene expression changes induced by PCB126-mediated elevation of DNA methyltransferase 3A …

Multicenter Stroke Preclinical Assessment Network Analysis Of Cardiovascular Risk Factor Subgroups Treated With The Poly(Adp-Ribose) Polymerase Inhibitor Veliparib, Raymond C Koehler, Karni Bedirian, Mu-Hsun Chen, Yanrong Shi, Suyi Cao, Brooklyn D Avery, Senthilkumar S Karuppagounder, Kazi Akhter, Adnan Bibic, Valina L Dawson, Ted M Dawson, Márcio A Diniz, Jessica Lamb, Karisma A Nagarkatti, Anjali Chauhan, Jaroslaw Aronowski, Louise D Mccullough, Andreia Lopes De Morais, Xuyan Jin, Cenk Ayata, Mariia Kumskova, Rakesh B Patel, Anil K Chauhan, Enrique C Leira, Pradip K Kamat, Mohammad B Khan, Krishnan M Dhandapani, David C Hess, Ligia S B Boisserand, Basavaraju G Sanganahalli, Lauren H Sansing, Patrick D Lyden

Faculty, Staff and Student Publications

Background: The Stroke Preclinical Assessment Network tested 6 therapeutic interventions initiated at the time of reperfusion after focal ischemic stroke in young mice, aging mice, obese mice, and spontaneously hypertensive rats. This randomized, controlled trial was conducted across 6 sites with concealed treatment and blinded neurobehavior assessments. The trial had an adaptive design with preset levels of efficacy and futility interrogated after each of 4 stages. The primary outcome was turning preference on the corner test at 1 month. The PARP (poly(ADP-ribose) polymerase) inhibitor, veliparib, was considered futile after the second stage when pooling all animal models (n=231 …

Preclinical Models Of Melanoma Leptomeningeal Disease To Assess Intrathecal Checkpoint Blockade, Renato A Guerrieri, Grant M Fischer, Jacob R Cortez, Barbara G Knighton, Debora A Ledesma, Courtney W Hudgens, Yimmy F Delcid, Qianghua Hu, Christian Y B Onana, Fernando C L Carapeto, Michael T Tezlaff, Jason T Huse, Patrick Hwu, Elizabeth M Burton, Isabella C Glitza Oliva, Michael A Davies, Sherise D Ferguson

Faculty, Staff and Student Publications

Leptomeningeal disease (LMD) is a subtype of central nervous system metastatic disease that is associated with poor patient outcomes and limited treatment options. There is an unmet need to develop preclinical models of LMD to expedite and improve the development of new therapeutics. Here, we describe the development of multiple orthotopic immunocompetent murine models of melanoma LMD, including their use to assess the efficacy of systemic and/or intrathecal immunotherapy. LMD was established by direct intrathecal injection of murine cell lines (B16-F10, BP, D4M, D4M-UV2, MC38-gp100, RMS, YUMM3.1, and YUMMER1.7) into the cisterna magna of C57BL/6 mice. Tumor take rate, distribution, …

Irf6 Regulates Adherens Junction Proteins And Inflammatory Cytokines In Salivary Acinar Cells And Its Expression Is Elevated In Sjӧgren’S Syndrome, Vi Pham, Antonio Hernandes Chaves Neto, Julia Zheng, Mary Elmeniawi, Krishna Kumar Kookal, Muhammad F Walji, Mary C Farach-Carson, Walid D Fakhouri

Faculty, Staff and Student Publications

Objective: To investigate the mechanism of Interferon Regulatory Factor 6 (IRF6) function in regulating adherens junction proteins and inflammatory cytokines in human salivary acinar cells and Sjögren's syndrome biopsies.

Design: We used mouse model, salivary cell lines, and human salivary gland (SG) biopsies to investigate IRF6 function in SG cellular integrity and immunomodulation.

Results: In Irf6-null mice, we observed myoepithelial cell detachment from acinar cells of major SGs, and the acini were remarkably disorganized compared to wild-type littermates. At the molecular level, the acinar differentiation markers E-cadherin and MIST1 were markedly reduced in Irf6-null embryonic SG, while the proinflammatory cytokines, …

Tofacitinib Ameliorates Campylobacter-Induced Intestinal Pathology By Suppressing Ifnγ Producing Ilcs And T Cells, Anna A Korchagina, Sergey A Shein, Wayne T Muraoka, Justin Nguyen, Qiangxing Chen, Anna A Tumanova, Austin W Todd, Carlos E Rivera, Rita Tamayo, Paolo Casali, Ekaterina Koroleva, Alexei V Tumanov

Faculty, Staff and Student Publications

Patients with autoimmune diseases are more susceptible to foodborne infections, which can be exacerbated by immunosuppressive therapy. Tofacitinib, a JAK/STAT pathway inhibitor, was recently approved for the treatment of ulcerative colitis, yet its effects on the pathogenesis of intestinal infections remain unclear. Here, we examined the impact of oral tofacitinib treatment in a mouse model of Campylobacter jejuni (C. jejuni) infection. Our results show that early tofacitinib administration attenuates intestinal pathology without affecting bacterial colonization. Specifically, tofacitinib suppressed CXCL1, CXCL2, CCL2 chemokine expression by intestinal epithelial cells, limiting recruitment of monocytes and neutrophils to the gut. In addition, JAK/STAT inhibition …

Adeno-Associated Virus-Mediated Silencing Of Sox4 Leads To Long-Term Amelioration Of Liver Phenotypes In Mouse Models Of Alagille Syndrome, Duncan Fox, Jun Xie, Jennifer L Burwinkel, Josh M Adams, Kashish Chetal, Marzieh Keivandarian, Yaniv Faingelernt, Sanjay Subramanian, Mario F Lopez, Anna L Peters, Nathan Salomonis, Neda Zarrin-Khameh, Guangping Gao, Stacey S Huppert, Hamed Jafar-Nejad

Faculty, Staff and Students Publications

Background & aims: In patients with Alagille syndrome (ALGS), bile duct paucity often leads to severe cholestatic phenotypes for which liver transplantation remains the only definitive treatment. No Food and Drug Administration-approved mechanism-based strategies exist to enhance biliary development in ALGS or other diseases with bile duct paucity. We aimed to identify a therapeutic target to address this unmet need.

Methods: Preclinical ALGS mouse models lacking 1 copy of Jag1 with or without conditional deletion of 1 or both copies of Sox9 were used. Sox4 levels were reduced genetically or with adeno-associated virus 8 (AAV8) vectors driving a Sox4-silencing sequence. …

Protein Kinase Rock1 Activates Mitochondrial Fission Linking To Oxidative Stress And Muscle Atrophy, Meijun Si, Jihong Chen, Rizhen Yu, Hongchun Lin, Feng Li, Sungyun Jung, Sandhya S Thomas, Farhard R Danesh, Yanlin Wang, Hui Peng, Zhaoyong Hu

Faculty, Staff and Students Publications

Introduction: Chronic kidney disease (CKD) is associated with protein-energy wasting, characterized by a reduction in muscle mass and strength. Although mitochondrial dysfunction and oxidative stress are implicated in the pathogenesis of muscle wasting, underlying mechanisms remain unclear.

Methods: Here, we used transcriptomic analysis, metabolomics analyses, and mouse gene manipulation to investigate the effects of mitochondrial plasticity and oxidative stress on muscle wasting the subtotal nephrectomy mouse models of CKD. The mice with CKD were age- and sex-matched to sham-operated controls.

Results: Through these approaches, Rho-associated kinase ROCK1 emerged as a key molecule responsible for the observed mitochondrial fission and oxidative …

Phosphorylation At Serine 214 Correlates With Tau Seeding Activity In An Age-Dependent Manner In Two Mouse Models For Tauopathies And Is Required For Tau Transsynaptic Propagation, Pablo Martinez, Nur Jury-Garfe, Henika Patel, Yanwen You, Abigail Perkins, Yingjian You, Audrey Lee-Gosselin, Ruben Vidal, Cristian A Lasagna-Reeves

Faculty, Staff and Students Publications

Background

Tau aggregation and propagation are hallmark features of Alzheimer's disease and related tauopathies. The molecular identity and post-translational modifications that contribute to tau seeding activity remain incompletely understood.

Objective

To characterize the temporal dynamics of tau seeding activity and identify specific phosphorylated tau species associated with tau propagation in vivo.

Methods

We profiled tau seeding activity using a FRET-based biosensor cell line and correlated it with the abundance of phospho- and conformational tau species in two transgenic mouse models of tauopathy (P301S-1N4R and P301S-0N4R). Immunohistochemistry and subcellular fractionation were used to examine the spatial distribution of tau species. Functional …

Exploring The Transformative Effects Of Calorie Restriction On The Lacrimal Gland In Adult Mice, Olivier Mauduit, Prashant Kumar, Kaitlin K Scholand, Emre Aksan, Laura Schaefer, Anmar Abu-Romman, Vanessa Delcroix, Zhiyuan Yu, Aude I Sindikubwabo, Ron Korstanje, Helen P Makarenkova, Cintia S De Paiva

Faculty, Staff and Students Publications

Advanced age is one of the most recognizable risk factors for dry eye. Dry eye disease affects millions worldwide and can result from age-related lacrimal gland dysfunction, which correlates with a decline in lacrimal gland secretory cell function and chronic inflammation. This study investigated the potential of calorie restriction to maintain lacrimal gland and ocular surface health. Adult female C57BL/6 J mice were subjected to a 40% calorie restriction for 4 months, starting at 6-7 months and continuing until 10-11 months. These mice were compared to controls fed ad libitum. Bulk RNA sequencing of lacrimal glands, conjunctiva, and cornea subjected …

Hydrogen Sulfide Inhibits Recruitment Of Monocyte-Derived Tumor Associated Macrophages In Glioblastoma By Downregulating Cxcl12, Joseph Camarano, Morgan Roque, Gabrielle Gahn, Stephen Garrett Whipple, Danielle Terrell, Charles Ronkon, Jamie Toms, Anthony Sin, Bharat Guthikonda, Khatri Latha, Yuhui Yang, Xinggui Shen, Christopher G Kevil, Ganesh Rao, Sungho Lee

Faculty, Staff and Students Publications

Tumor associated macrophages (TAMs) directly contribute to the dismal prognosis of glioblastoma by preventing anti-tumor immunity and promoting tumor invasion and angiogenesis. Inhibiting TAM infiltration is a potential therapeutic strategy in glioblastoma, with several chemokine antagonists in early clinical development. Hydrogen sulfide, a gasotransmitter that regulates microglial accumulation in a wide range of CNS diseases, may be a novel therapeutic target to prevent TAM recruitment in glioblastoma. In this study, hydrogen sulfide concentrations were directly measured from 14 isocitrate dehydrogenase (IDH)-wildtype glioblastoma surgical samples and compared against overall survival as well as expression of TAM markers and chemokines. Effects of …

Nrf2 Hyperactivation As A Driver Of Radiotherapy Resistance And Suppressed Antitumor Immunity In Head And Neck Squamous Cell Carcinoma, Rutulkumar Patel, Kalil Saab, Lixia Luo, Yan Ma, Rashid Abdullah Osman, Nerissa T Williams, Jeffrey Everitt, Maciej J Zelazowski, Patricia Castro, William K Decker, William H Hudson, Jeffrey N Myers, Vlad C Sandulache, Mitchell J Frederick, Yvonne M Mowery, David G Kirsch

Faculty, Staff and Students Publications

Purpose: Alterations in the KEAP1/NFE2L2 (NRF2)/CUL3 pathway occur in ∼20% of human head and neck squamous cell carcinomas (HNSCC) and are associated with resistance to standard-of-care therapy. However, this pathway's role in radiotherapy resistance in HNSCC has not been well studied.

Experimental design: We generated genetically engineered mouse models and developed primary murine cancer cell lines harboring mutations commonly observed in human HNSCC, including inducible activation of PIK3CA and deletion of Trp53, with or without Keap1 loss. Primary tumors were initiated via 4-hydroxytamoxifen injection ± the tobacco carcinogen benzo[a]pyrene (BAP) into the oral buccal mucosa. Tumors were analyzed by Western …

Protocol For Non-Invasive Pulsed-Doppler Evaluation Of Blood Flow In The Mouse Ophthalmic Artery, Radwa Awad, Emil Martin, Anilkumar K Reddy, Iraida Sharina

Faculty, Staff and Student Publications

The number of reliable and non-invasive techniques to characterize ocular blood flow is limited. Here, we present a protocol for identifying a soft tissue window in the orbital aperture using pulsed-Doppler ultrasonography to offer real-time, non-invasive blood flow velocity monitoring in the mouse ophthalmic artery. We describe steps for preparing a mouse, positioning the ultrasound probe, and acquiring and recording signals. We then detail procedures for analyzing results using a workstation equipped with Doppler flow velocity software. For complete details on the use and execution of this protocol, please refer to Sharina et al.

Sorting Nexin 3 Promotes Ischemic Retinopathy Through Rip1- And Rip3-Mediated Myeloid Cell Necroptosis And Mitochondrial Fission, Jiaojiao Wang, Chunhong Zhou, Kai Zhuang, Jiami Zou, Wanlu Qiu, Mei Jin, Weile Ye, Pinglian Yang, Zhihua Zheng, Qing Zhou, Zunnan Huang, Yuanxiang Wang, Peiqing Liu, Jing Lu, Yuqing Huo, Zhiping Liu

Faculty, Staff and Students Publications

Proliferative retinopathy is a leading cause of irreversible blindness in humans; however, the molecular mechanisms behind the immune cell–mediated retinal angiogenesis remain poorly elucidated. Here, using single-cell RNA sequencing in an oxygen-induced retinopathy (OIR) model, we identified an enrichment of sorting nexin (SNX)-related pathways, with SNX3, a member of the SNX family that is involved in endosomal sorting and trafficking, being significantly upregulated in the myeloid cell subpopulations of OIR retinas. Immunostaining showed that SNX3 expression is markedly increased in the retinal microglia/macrophages of mice with OIR, which is mainly located within and around the neovascular tufts. Myeloid cell-specific deficiency …

Setd2 Suppresses Tumorigenesis In A Krasg12c-Driven Lung Cancer Model, And Its Catalytic Activity Is Regulated By Histone Acetylation, Ricardo J Mack, Natasha M Flores, Geoffrey C Fox, Hanyang Dong, Metehan Cebeci, Simone Hausmann, Tourkian Chasan, Jill M Dowen, Brian D Strahl, Pawel K Mazur, Or Gozani

Faculty, Staff and Student Publications

Histone H3 trimethylation at lysine 36 (H3K36me3) is a key chromatin modification that regulates fundamental physiological and pathological processes. In humans, SETD2 is the only known enzyme that catalyzes H3K36me3 in somatic cells and is implicated in tumor suppression across multiple cancer types. While there is considerable crosstalk between the SETD2-H3K36me3 axis and other epigenetic modifications, much remains to be understood. Here, we show that Setd2 functions as a potent tumor suppressor in a KRASG12C-driven lung adenocarcinoma (LUAD) mouse model, and that acetylation enhances SETD2 in vitro methylation of H3K36 on nucleosome substrates. In vivo, Setd2 ablation accelerates lethality in …

Infusion Of Blood From Young And Old Mice Modulates Amyloid Pathology, Matias Pizarro, Ruben Gomez-Gutierrez, Ariel Caviedes, Catalina Valdes, Ute Woehlbier, Cristian Vargas, Mauricio Hernandez, Claudia Duran-Aniotz, Rodrigo Morales

Faculty, Staff and Student Publications

Alzheimer's disease (AD) is a neurodegenerative disease characterized by the accumulation of misfolded proteins in the brain. Recently, the impact of blood components in the progression of this disease has come to attention. This study investigates the effects of infusing blood from young and old wild-type mice into transgenic mice that model AD brain amyloidosis. Impaired memory and Aβ accumulation were observed in mice infused with blood from old donors. A proteomic analysis in the brain of these mice identified alterations in components related to synaptogenesis and the endocannabinoid system. The α2δ2 protein, associated with neuronal calcium regulation, was validated …

Dissecting The Effect Of Mitochondrial Bcat Inhibition In Methylmalonic Acidemia, Madeline G Hemmingsen, Guo-Fang Zhang, Yunhan Ma, Hannah Marchuk, Kalyani R Patel, Tong Chen, Xinning Li, Mark Chapman, Sabrina Collias, Dolores H Lopez-Terrada, James Beasley, Ashlee R Stiles, Randy J Chandler, Charles P Venditti, Sarah P Young, Mercedes Barzi, Beatrice Bissig-Choisat, Doug Krafte, Christopher B Newgard, Karl-Dimiter Bissig

Faculty, Staff and Students Publications

Methylmalonic acidemia (MMA) is a severe metabolic disorder affecting multiple organs because of a distal block in branched-chain amino acid (BCAA) catabolism. Standard of care is limited to protein restriction and supportive care during metabolic decompensation. Severe cases require liver/kidney transplantation, and there is a clear need for better therapy. Here, we investigated the effects of a small molecule branched-chain amino acid transaminase (BCAT) inhibitor in human MMA hepatocytes and an MMA mouse model. Mitochondrial BCAT is the first step in BCAA catabolism, and reduction of flux through an early enzymatic step is successfully used in other amino acid metabolic …

Persistent Na+ Current Couples Spreading Depolarization To Seizures In Scn8a Gain-Of-Function Mice, Isamu Aiba, Yao Ning, Jeffrey L Noebels

Faculty, Staff and Students Publications

Spreading depolarization (SD) is a slowly propagating wave of massive cellular depolarization that transiently impairs the function of affected brain regions. Although SD typically arises as an isolated hemispheric event, we previously reported that reducing M-type potassium current (IKM) by ablation of Kcnq2 in forebrain excitatory neurons results in tightly coupled spontaneous bilateral seizure–SD complexes in the awake mouse cortex.

Here we find that enhanced persistent Na+ current attributable to gain-of-function mutations in Scn8a (N1768D/+, hereafter D/+) produces a similar compound cortical excitability phenotype. Chronic direct-current (DC)-band EEG recording detected spontaneous bilateral seizure–SD complexes accompanied by seizures with …

The Potential Of 4-Methylumbelliferone To Be Repurposed For Treating Liver Fibrosis, Xi Chen, Huiqiao Li, Yanru Deng, Jieyi Meng, Shangang Zhao, Clavia Ruth Wooton-Kee, Xia Gao, Bingning Dong, Dongyin Guan, Chaodong Wu, Philipp E Scherer, Yi Zhu

Faculty, Staff and Students Publications

4-Methylumbelliferone (4-MU) is the active component of hymecromone, a choleretic and antispasmodic drug with an excellent safety profile. In rodent studies, high doses of 4-MU are also used to inhibit the production of hyaluronan (HA), a biomarker of liver fibrosis. Further, 4-MU shows excellent efficacy in inhibiting liver fibrosis of different etiologies in animal studies, eliciting interest in its repurposing for this condition. However, 4-MU's mechanism of action, and whether it inhibits liver fibrosis by impeding HA synthesis remains unclear. Using several transgenic mouse models with HA overproduction or degradation in different types of liver cells, we found that both …

Coenzyme Q Headgroup Intermediates Can Ameliorate A Mitochondrial Encephalopathy, Guangbin Shi, Claire Miller, Sota Kuno, Alejandro G Rey Hipolito, Salsabiel El Nagar, Giulietta M Riboldi, Megan Korn, Wyatt C Tran, Zixuan Wang, Lia Ficaro, Tao Lin, Quentin Spillier, Begoña Gamallo-Lana, Drew R Jones, Matija Snuderl, Soomin C Song, Adam C Mar, Alexandra L Joyner, Roy V Sillitoe, Robert S Banh, Michael E Pacold

Duncan NRI Faculty and Staff Publications

Decreased brain levels of coenzyme Q10 (CoQ10), an endogenously synthesized lipophilic antioxidant1,2, underpin encephalopathy in primary CoQ10 deficiencies3,4 and are associated with common neurodegenerative diseases and the ageing process5,6. CoQ10 supplementation does not increase CoQ10 pools in the brain or in other tissues. The recent discovery of the mammalian CoQ10 headgroup synthesis pathway, in which 4-hydroxyphenylpyruvate dioxygenase-like protein (HPDL) makes 4-hydroxymandelate (4-HMA) to synthesize the CoQ10 headgroup precursor 4-hydroxybenzoate (4-HB)7, offers an opportunity to pharmacologically restore CoQ10 synthesis and mechanistically treat CoQ10 deficiencies. To test whether 4-HMA …

Targeting Sting To Disrupt Macrophage-Mediated Adhesion In Encapsulating Peritoneal Sclerosis, Juan Sun, Yuxiang Sun, Dandan Guo, Huolin Ye, Qiang Huang, Hu Zhou, Canming Li, Mei Liao, Yujia You, Hongli Shang, Pan Zhou, Dongxuan Wu, Janusz Witowski, Zhaoyong Hu, Hui Peng

Faculty, Staff and Students Publications

Encapsulating peritoneal sclerosis (EPS) is a life-threatening fibrotic condition characterized by severe abdominal adhesions, chronic inflammation, and significant morbidity. The lack of effective treatments for EPS stems from a limited understanding of its underlying mechanisms. In this study, we developed a modified mouse model of PD-induced EPS and investigated the role of the STING signaling pathway in disease progression. Our findings reveal that STING activation in peritoneal mesothelial cells significantly increases the secretion of the macrophage chemokine CCL2, leading to enhanced macrophage infiltration and the formation of pathological adhesions. Notably, pharmacological inhibition of STING using the inhibitor H151 effectively reduced …

Prefrontal Cortex Astrocytes Modulate Distinct Neuronal Populations To Control Anxiety-Like Behavior, Eunyoung Kim, Hairuo Du, Yanqi Tan, Brandon L Brown, Yaowen Chang, Blanca Díaz-Castro, Jonathan V Sweedler, Xinzhu Yu

Faculty, Staff and Student Publications

Accumulating evidence has supported diverse regulatory functions of astrocytes in different neural circuits as well as various aspects of complex behaviors. However, little is known about how astrocytes regulate different neuronal subpopulations that are linked to specific behavioral aspects within a single brain region. Here, we show that astrocytes in the medial prefrontal cortex (mPFC) encode anxiogenic environmental cues in freely behaving mice. Silencing mPFC astrocyte Ca

Trpc4 Regulates Limbic Behavior And Neuronal Development By Stabilizing Dendrite Branches Through Actomyosin-Driven Integrin Activation, Jaepyo Jeon, Travis I Moore, Insuk So, Marc Freichel, Veit Flockerzi, Lutz Birnbaumer, Michael X Zhu

Faculty, Staff and Student Publications

Transient Receptor Potential Canonical 4 (TRPC4) channels have been implicated in multiple neurological functions, including anxiety and sociability. TRPC4 variants were also found in patients with autism. However, the contributions of TRPC4 to neurodevelopment remain undefined. Here, we show that neurobehavioral deficits appear early in young TRPC4 knockout (Trpc4^−/−) mice immediately after weaning, manifesting as alterations in multiple, limbic-related behaviors, such as nesting, marble burying, burrowing, self-grooming, and social interactions. Hippocampal neurons of Trpc4−/− mice exhibit reduced dendritic arborization both in vivo and in vitro. Mechanistically, we found that TRPC4 expression in dendrites surged at the …