Medical Sciences Commons^™

Rab4 Spatially And Functionally Converges With Rab7 In The Degradative Endolysosomal Network, Stephen M Farmer, Shiyu Xu, Yue Yu, Xin Ye, Haoyi Yang, Jing Cai, Beatriz Rios, Wen-Wen Lin, Daniela Covarrubias, Vicky Chuong, Lili Ye, German Zylberberg, Charissa Wang, Erin Furr-Stimming, Qingchun Tong, Oguz Kanca, Hugo J Bellen, Travis I Moore, Sheng Zhang

Faculty, Staff and Students Publications

Rab GTPases are key regulators of endosomal trafficking in eukaryotes. In mammalian cells, Rab4 and Rab7 were shown to localize to distinct compartments, with Rab4 on early endosomes for fast recycling and Rab7 on late endosomes for degradation. Here, we show that in Drosophila, endogenous Rab4 and Rab7 extensively colocalize across tissues and developmental stages. Recruited to the same compartments through mechanisms that do not require the activity of the other, they have opposing effects on endolysosomal size: Rab4 overexpression or Rab7 impairment leads to enlarged endolysosomes, whereas Rab4 loss or constitutively active Rab7 reduces their sizes. Rab4 deficiency suppresses …

Histone Demethylase Jmjd1a Protects Mice From Enteric Bacterial Infection By Upregulating Ccl8 Expression To Recruit Macrophages And Cd4+ T Cells, Guifang Lin, Lichun Yang, Shuyan Jiang, Yong Zhang, Ping Luo, Weihua Li, Jianming Xu, Gongpeng Xiong, Chundong Yu, Wenbo Chen

Faculty, Staff and Students Publications

Jumonji domain-containing 1A (JMJD1A, also known as KDM3A) is a histone demethylase that specifically demethylates H3K9me1/2 to enhance gene expression. The roles of JMJD1A in many physiological and pathological processes have been revealed. However, it is unclear whether JMJD1A is involved in host defense against enteric pathogen infection. In this study, we found that enteric infection with C. rodentium induced JMJD1A expression in colonic epithelial cells at the transcriptional level partly mediated by IRF1. After C. rodentium infection, JMJD1A-/- mice exhibited increased mortality, colonic injury, and C. rodentium load and systemic spread, suggesting that JMJD1A protects host against C. rodentium …

Distributed Battery-Free Bioelectronic Implants With Improved Network Power Transfer Efficiency Via Magnetoelectrics, Joshua E Woods, Fatima Alrashdan, Ellie C Chen, Wendy Tan, Mathews John, Lukas Jaworski, Drew Bernard, Allison Post, Angel Moctezuma-Ramirez, Abdelmotagaly Elgalad, Alexander G Steele, Sean M Barber, Philip J Horner, Amir H Faraji, Dimitry G Sayenko, Mehdi Razavi, Jacob T Robinson

Faculty, Staff and Students Publications

Networks of miniature implants could enable simultaneous sensing and stimulation at different locations in the body, such as the heart and central or peripheral nervous system. This capability would support precise disease tracking and treatment or enable prosthetic technologies with many degrees of freedom. However, wireless power and data transfer are often inefficient through biological tissues, particularly as the number of implanted devices increases. Here we show that magnetoelectric wireless data and power transfer supports a network of millimetre-sized bioelectronic implants in which system efficiency improves with additional devices. We demonstrate wireless, battery-free networks ranging from one to six implants, …

The Evolving Therapeutic Landscape Of Pcsk9 Inhibition, Brett S Mansfield, Yakubu Bene-Alhasan, Christie M Ballantyne, Frederick J Raal

Faculty, Staff and Students Publications

Cardiovascular disease remains the leading cause of death worldwide with low density lipoprotein being a major, yet modifiable, risk factor. Proprotein convertase subtilisin/kexin type 9 (PCSK9) plays a central role in regulating low density lipoprotein (LDL) receptor expression. Naturally occurring loss-of-function variants in the PCSK9 gene result in lifelong lower LDL cholesterol (LDL-C) levels and significantly lower risk of atherosclerotic cardiovascular disease (ASCVD), providing strong genetic validation of PCSK9 as a therapeutic target. This insight has driven the development of therapies directed at PCSK9 for the management of hypercholesterolaemia, particularly in patients who fail to meet LDL-C targets despite maximally …

Toward Scientific Rigor: Setting Standards For Indirect Calorimetry Analysis And Reporting, Elizabeth L Lieu, Mark A Herman, Sean M Hartig

Faculty, Staff and Students Publications

Indirect calorimetry determines energy expenditure by measuring respiratory gas exchange. The approach is based on the principle that nutrient metabolism consumes O2 and produces CO2 and water in predictable ratios that can be compared with heat production. Due to the impracticality and high cost of direct calorimetry, indirect calorimetry is the major approach for modern metabolic studies in preclinical models. Despite the broad adoption of this method in rodent phenotyping, the field has lacked standardized methods for analyzing, representing, and sharing these data, limiting scientific progress. The recent review in Nature Metabolism by the International Indirect Calorimetry Consensus Committee (IICCC) …

Alpha 7 Nicotinic Acetylcholine Receptor Contributes To Long-Term Cognitive Recovery Following Ischemic Stroke, Dustin T Nguyen, Kate Mendoza, Cassandra Hall, Chunfeng Tan, Anjali Chauhan

Faculty, Staff and Student Publications

Stroke is associated with autonomic dysfunction and reduced acetylcholine (ACh), a neurotransmitter critical for cognition. ACh signals in part through the alpha-7 nicotinic acetylcholine receptor (α7nAChR), a ligand-gated ion channel involved in synaptic plasticity, learning, and memory. Impaired α7nAChR signaling has been linked to heightened neuroinflammation and poor acute stroke recovery. Here, we investigated whether α7nAChR contributes to post-stroke cognitive recovery in young male mice. Wild-type (WT) and α7nAChR knockout (α7n0KO) mice underwent 60-min middle cerebral artery occlusion (MCAO). In a pharmacology cohort, the α7nAChR agonist GTS-21 was administered immediately after reperfusion and then daily for 20 days. Cognitive performance …

Fgl2-Knockout Tumor Cells Serve As A Vaccine Inducing Long-Duration Brain-Resident Memory T Cells That Reject Subsequent Intracranial Tumor Cell Challenges, Sheng Zhang, Yining Jin, Zhiliang Jia, Xueqing Xia, Yang Li, Qi Wang, Jing Wang, Jian Wang, Joya Chandra, Gregory K Friedman, Shulin Li

Faculty, Staff and Student Publications

The failure to prevent brain tumors, including both recurrent primary and metastatic brain tumors, is the primary cause of patients' mortality. We developed a novel whole tumor-cell vaccine to rapidly induce long-duration brain-resident memory T (TRM) cells that prevent brain tumor progression. Ten Fgl2-KO primary and metastatic tumor cell lines, generated via CRISPR/Cas9, were used to vaccinate mice and for intracranial challenges with the WT tumor cells. Not only did vaccinated mice reject these tumor cell challenges, but also more than half of these mice became long-duration survivors. Transplanting brain immune cells from vaccinated mice into naïve mice enabled this …

Spatial Profiling Reveals Distinct Molecular And Immune Evolution Of Mouse Lung Adenocarcinoma Precancers With Or Without Carcinogen Exposure, Bo Zhu, Muhammad Aminu, Pingjun Chen, Jian-Rong Li, Chuanpeng Dong, Chenyang Li, Yanhua Tian, Shao-Wei Lu, Hong Chen, Chenxi Ma, Xin Hu, Jie Ye, Andrew Y Liu, Beibei Huang, Frank R Rojas, Parra Cuentas Edwin Roger, Ou Shi, Monique B Nilsson, Alissa Poteete, Khaja B Khan, Wei Lu, Luisa M Solis Soto, Junya Fujimoto, Cara Haymaker, Ignacio I Wistuba, Zhubo Wei, Linghua Wang, Don L Gibbons, Ken Chen, Alexandre Reuben, Jason M Schenkel, John V Heymach, Chao Cheng, Jia Wu, Jianjun Zhang

Faculty, Staff and Student Publications

Tumor evolution involves genetic, transcriptional, and phenotypic alterations that shape cancer cell behavior and interactions with the microenvironment. While single‐cell technologies have advanced our understanding of this process, spatial dynamics remain incompletely characterized. Here, whole‐exome sequencing (WES), imaging mass cytometry (IMC), and spatial transcriptomics (ST) were integrated to study molecular evolution and immune responses in two lung adenocarcinoma (LUAD) mouse models: a genetically engineered model (129S4/Sv‐KrasLSL‐G12D, termed 129S4 K) and a carcinogen‐induced precancer model (129S4 U). Compared to 129S4 K, 129S4 U tumors exhibited higher mutational, neoantigen but lower copy number variation (CNV) burdens at matched developmental timepoints, consistent with …

Beyond Short Microhomologies: Mismatch-Compatible Pol Θ-Mediated Dna Damage Repair, Yuzhen Li, Richard D Wood

Faculty, Staff and Student Publications

DNA polymerase θ (Pol θ)-mediated end-joining (TMEJ), one of several pathways for repairing DNA double-strand breaks, is traditionally thought to initiate via anchoring at short, consecutive, and perfectly matched microhomologies (MHs). Emerging evidence indicates that Pol θ can utilize MHs containing mismatches both in vitro and in vivo. This revised definition of MH provides a mechanistic explanation for a broader spectrum of Pol θ-dependent repair outcomes. Here, we summarize recent findings on the revised definition of MHs utilized by Pol θ, assess the applicability of this concept across species, and compare TMEJ with other (micro)hom(e)ology-mediated repair pathways. We explore how …

Pharmacokinetic Modeling Strategies For Dynamic Hyperpolarized Urea Imaging, Keith A Michel, Collin J Harlan, Christopher M Walker, Matthew E Merritt, Yunyun Chen, Stephen Y Lai, James A Bankson

Faculty, Staff and Student Publications

Purpose: To evaluate pharmacokinetic modeling methods for quantification of tissue perfusion/permeability with hyperpolarized 13C urea.

Methods: Three models for quantitative analysis of dynamic HP urea imaging data were proposed and evaluated in numerical simulations and a thyroid cancer mouse model. A multicompartment model resembling the extended Tofts model for DCE-MRI (Model I) and two simplified models were used. The simplified models each eliminate a volume parameter representing vascular (Model II) or impermeable cellular space (Model III). Signal curves were generated from Model I, and models were fit to these synthetic data to quantify the effects of acquisition settings, bias in …

Shiga Toxin Increases Intestinal Transit To Displace Resident Microbes And Facilitate Pathogen Colonization, Max A Odem, Sabona B Simbassa, Cecilia Fadhel Alvarez, Oliyad Jeilu, Shelby R Simar, Rachel Bosserman, Soumita Dutta, Walter Galdamez, Hossaena Ayele, Blake M Hanson, Diana M Proctor, Anne Marie Krachler

Faculty, Staff and Student Publications

Shiga toxin (Stx)-producing Escherichia coli (STEC) is a major cause of food-borne illnesses, and disease severity correlates with the production of Shiga toxins. While clinical symptoms such as bloody diarrhea and hemolytic uremic syndrome have been attributed to Stx, its contribution to bacterial fitness is not well understood. Here, we demonstrate that Stx2 enhances STEC colonization of the zebrafish gut by facilitating the partial displacement of gut resident microbes. Infection with Stx2-producing STEC strains or direct exposure of fish to purified Stx2 induces alterations in the zebrafish microbiome structure, impacting several bacterial phyla and genera, notably Pseudomonads. We show that …

Diversity And Immune Dynamics Of Choroid Plexus Macrophages Are Shaped By Distinct Developmental Origins, Siling Du, Khai M Nguyen, Alina Ulezko Antonova, Jose L Fachi, Patrick Fernandes Rodrigues, Alice Verdiani, Martina Molgora, Igor Smirnov, Jasmin Herz, Tornike Mamuladze, Jennifer Ponce, Amanda Swain, Mattia Bugatti, Susan Gilfillan, Marina Cella, William Vermi, Jonathan Kipnis, Marco Colonna, Simone Brioschi

The Brown Foundation: Institute of Molecular Medicine

The choroid plexus forms a key barrier and signaling interface between the brain and peripheral circulation, yet its immune landscape remains incompletely understood. Using single-cell transcriptomics combined with lineage and spatial tracing methods, we identified three biologically distinct populations of choroid plexus macrophages, defined by differential expression of CD163, MHCII or CD9. These subsets arise from separate hematopoietic waves, occupy distinct anatomical niches and differentially rely on CSF1 and IL-34 for survival. We found that TGFβ signaling is essential to maintain their tissue-specific identities, and deletion of Tgfbr2 in these cells induces broad phenotypic reprogramming. During neuroinflammation, choroid plexus macrophages …

Glutamatergic Dysfunction Of Astrocytes In Paraventricular Nucleus Of Thalamus Contributes To Adult Anxiety Susceptibility In Adolescent Ethanol Exposed Mice, Aubrey Bennett, Hyunjung Kim, David Thomas, Peter Biggs, Roxan Ara, Asamoah Bosomtwi, Seungwoo Kang

The Brown Foundation: Institute of Molecular Medicine

Repeated ethanol exposure during adolescence increases adult anxiety risk, but the underlying mechanisms remain unclear. The paraventricular nucleus of the thalamus (PVT) has been considered a hub for controlling anxiety and is affected by experiences from early life. Thus, this study investigated how adolescent intermittent repeated ethanol exposure (AIE) affects the PVT activities and anxiety-related behaviors in adulthood. We found that AIE triggers anxiety-like behaviors and parallelly exhibited elevated firing rates and increased calcium signaling in the PVT neurons compared to control counterpart mice. Chemogenetic inhibition of PVT neurons reduced anxiety-like behaviors in AIE-treated animals, confirming PVT's role in adolescent …

Lipids Grease The Chain Of Cancer Progression, Joseph Rupert, Pham Hong Anh Cao, Daniel E Frigo, Mikhail G Kolonin

The Brown Foundation: Institute of Molecular Medicine

The role of lipids in cancer progression has become a fervent area of exploration. The crosstalk of tumors with adipose tissue is a complex but well-regulated orchestration of signaling pathways, lipid transporters, and enzymes. They regulate fatty acid synthesis, their deposition into lipid droplets (LDs) as triglycerides, induction of lipolysis, shuttling lipids across cells, and their systemic trafficking, modification, and catabolism. For the latter, lipid oxidation has emerged as a metabolic process of particular clinical importance. Products of lipid processing can become secondary messengers, contribute to reactive oxygen species (ROS) generation, stimulate the production of antioxidants, and, if left unchecked, …

Non-Synaptic Function And Localization Of Syntaxin-Binding Protein 1 In A Mouse Model Of Stxbp1-Related Epileptic Encephalopathy, Tao Yang, Rajat Banerjee, Yamei Deng, Sheetal Jahagirdar, Joo Hyun Kim, Wu Chen, Mingshan Xue, Alexey I Nesvizhskii, Michael D Uhler, Jack M Parent, Yu Wang

Duncan NRI Faculty and Staff Publications

Objective: De novo mutations in the syntaxin-binding protein 1 (STXBP1), encoded by STXBP1, are among the most prevalent causes of variable neurodevelopmental disorders, including epileptic encephalopathy, developmental delay, and movement disorders. Although STXBP1 has been proposed as a critical presynaptic protein controlling synaptic vesicle exocytosis, clinical phenotypes also suggest that its biological function could be more diverse.

Methods: The expression pattern of STXBP1 was studied using immunostaining in vitro and in vivo. Synaptosome isolation was performed to investigate the synaptic and non-synaptic localization of STXBP1 in the brain. STXBP1 immunoprecipitation followed by mass spectrometry (MS) was conducted to identify protein …

Prenatal Stress Induces Changes In Behavior, Hpa Axis, Inflammation, And Oxidative Stress In Adult Rats Offspring, Jorge M Aguiar-Geraldo, Jefté Peper-Nascimento, José Henrique Cararo, Taise Possamai-Della, Alexandra I Zugno, Anilkumar Pillai, João Quevedo, Samira S Valvassori

Faculty, Staff and Student Publications

Prenatal stress is related to the development of psychiatric disorders involving inflammation, oxidative stress, and hypothalamic-pituitary-adrenal (HPA) axis. Therefore, the aim of the present study was to evaluate the effects of prenatal stress on behavior, inflammation, oxidative stress, and the HPA-axis in the dams and their offspring treated with lithium. Thirteen pregnant Wistar rats were exposed to a prenatal chronic unpredictable stress protocol from the 14th day of gestation until birth. At the 60th postnatal day (PND), a treatment protocol was carried out in the offspring with lithium (intraperitoneally - 47.5 mg/kg) or saline for seven days (twice a day). …

Celf1 Is A Non-Canonical Eif4e Binding Protein That Promotes Translation Of Epithelial-Mesenchymal Transition Effector Mrnas, Arindam Chaudhury, Natee Kongchan, Shebna A Massey, Rajesh Sharma, Rituraj Pal, Na Zhao, Phoebe Tsoi, Yingmin Zhu, Emuejevoke Olokpa, Sufeng Mao, Sonia Del Rincon, Lucas C Reineke, Richard E Lloyd, Marco Sardiello, Jeffrey M Rosen, Choel Kim, Josephine C Ferreon, Joel R Neilson

Faculty, Staff and Students Publications

Mounting evidence is revealing an increasing complexity of gene regulation at the level of messenger RNA (mRNA) translation. Within mammalian cells, canonical cap-dependent mRNA translation depends on the eIF4F complex, consisting of the m7G mRNA cap-binding protein eukaryotic initiation factor 4E (eIF4E), the helicase eIF4A (eIF4A), and the eIF4G (eIF4G1) scaffolding protein. eIF4G1 additionally binds poly(A) binding protein (PABPC1) to facilitate mRNA circularization and nucleates pre-translation initiation complex assembly to initiate ribosomal scanning. In breast epithelial cells, the CELF1 RNA-binding protein specifically promotes the translation of select epithelial-to-mesenchymal transition (EMT) effector mRNAs by binding GU-rich elements (GREs) within their 3' …

Supt16h-Associated Neurodevelopmental Disorder And Neurocristopathy: Genetic And Phenotypic Spectrum, Eunhye Lee, Seungmin Sim, Hee-Jung Choi, Eugene Y Liang, Carolyn Le, Roya Bina, Ryan Cohen, Elizabeth George, Soo Yeon Kim, Gifty Bhat, Erin Falsey, Richard Sidlow, Kristin Clinard, Shay Ben-Shachar, Eleina England, Beatriz Menendez, Isabella Herman, Shelly Nielsen, Jaya Punetha, Priya Bhola, J Austin Hamm, Megan A Keeney, Nike Sitzman, Sara Berger, Lakshmi Mehta, Alison J Conn, Lilian Downie, Myla Ashfaq, Hope Northrup, Ange-Line Bruel, Sylvie Odent, Justin O Szot, Noelia Nunez Martinez, Sunju Park, Julie Refkin, Jean-Marc Good, Fabienne Maurer, Cédric Le Caignec, David J Coman, Erin Anderson, Linda J Richards, Ryan J Dean, Caleb Yang, Chulwon Choi, Byung Joon Hwang, Jin Sook Lee, William B Dobyns, Murim Choi, Elliott H Sherr, Jong-Hee Chae, Yun Kee, Emanuela Argilli

Faculty, Staff and Student Publications

SUPT16H encodes a subunit of the FACT (FAcilitates Chromatin Transcription) complex, a histone chaperone essential for maintaining chromatin integrity during transcription, replication, and DNA repair. Pathogenic de novo SUPT16H missense variants have previously been linked to neurodevelopmental disorders in eight individuals. Here, we expand the genotypic and phenotypic spectrum by identifying 24 additional individuals harboring ultrarare heterozygous missense or truncating variants, who share overlapping clinical features including intellectual disability, autism spectrum disorder, hypotonia, and characteristic craniofacial dysmorphism. To elucidate the underlying mechanisms, we generated a supt16h knockout zebrafish model using CRISPR/Cas9. The supt16h loss-of-function (LOF) model recapitulated key patient phenotypes …

Cerebral Hypoperfusion Causes Behavioral Changes And Impairs The Rod Photoreceptor Pathway In The Retina Of Aged Mice, Spencer Talmage Barney, Daniela Becerril, Sheelu Monga, Samantha Flores, Audrey Lee, Marlon Fraga Mattos, Ross M Perez, Frank W Blixt, Michael Maniskas, Shuning Huang, Hongyu Wu, Chunfeng Tan, Louise D Mccullough, Elizabeth Zuniga-Sanchez, Jose Felix Moruno-Manchon

Faculty, Staff and Student Publications

Gradual reduction of cerebral blood flow occurs with aging, and it is a major cause of vascular dementia, a group of dementias with a cerebrovascular component. Interestingly, patients who have suffered a vascular insult may develop retinopathy, which may occur as an early symptom of vascular dementia. Several rodent models using young animals have been generated to mimic retinopathy caused by cerebral hypoperfusion; however, given that aging is an important factor in developing vascular dementia and hypoperfusion retinopathy, we propose to use aged (17-month-old) mice in a model of cerebral hypoperfusion. In this model, we implant two metallic micro-coils (0.16 …

The Neuroprotective Effects Of Alpha-Tocopherol As An Anti-Inflammatory Agent: Mechanistic Insights And Therapeutic Challenges, Megumi H Seese, Yuanzhong Xu

The Brown Foundation: Institute of Molecular Medicine

Vitamin E (alpha-tocopherol, αToc), an antioxidant fat-soluble vitamin that prevents lipid peroxidation and modulates pro-inflammatory cytokine production, is well-known to be critical for neuroprotection. However, the underlying mechanism remains poorly understood. Accumulating evidence demonstrates that αToc influences neuroinflammatory processes. Here, we review recent research progress on the effects of αToc on neuroinflammation. Preclinical studies included in this narrative review were identified through PubMed searches using the keywords "alpha-tocopherol AND neuroinflammation or alpha-tocopherol AND brain AND inflammation". While many studies support a neuroprotective role of αToc, the magnitude and direction of its effects vary substantially depending on dosage, route of administration, …

Unbalanced Chromatin Binding Of Polycomb Complexes Drives Neurodevelopmental Disorders, Rodrigo L Borges, Gretter González-Blanco, Harikumar Arigela, Yingyu Huang, Lucas D Caeiro, Nikolai Fattakhov, Stefano Lepore, Liliana Garcia-Martinez, Matea Maurice, Pushti D Mehta, Emily J Park, Kailynn Macgillivray, Jevithen Nehru, Matthew Chau, Maria C Robayo, Clemer Abad, Alicia Bilbao-Martinez, Fabiola Monteiro, Xi Luo, Song Tan, Daniel Bilbao, Simone Sidoli, Bruno Di Stefano, Katherina Walz, Arneet L Saltzman, Ramiro E Verdun, Ramin Shiekhattar, Lluis Morey

Faculty, Staff and Students Publications

The prevalence of neurodevelopmental disorders (NDDs) in children is increasing, yet their underlying causes remain largely unknown. We identified heterozygous mutations in the Polycomb repressive complex 1 (PRC1) E3 ligases RING1 and RNF2 in individuals with NDDs and revealed distinct mechanisms by which they compromise PRC1 activity. We developed cellular and mouse models carrying the Ring1b

Sex-Specific Differences In Mediobasal Hypothalamus In Response To Nutritional States, Jonathan C Bean, Jinjing Jian, Tzu-Chiao Lu, Hailan Liu, Kristine Conde, Darah A Threat, Sanika V Jossy, Megan E Burt, Jingjing Cheng, Yue Deng, Xing Fang, Xiaoyu Geng, Junying Han, Yongxiang Li, Hesong Liu, Qingzhuo Liu, Yutian Liu, Yuhan Shi, Longlong Tu, Mengjie Wang, Xu Xu, Yuxue Yang, Meng Yu, Xinming Liu, Meixin Sun, Fuhui Wang, Olivia Z Ginnard, Yongjie Yang, Yang He, Chunmei Wang, Yanyan Qi, Hongjie Li, Yong Xu

Children’s Nutrition Research Center Staff Publications

The arcuate nucleus of the hypothalamus plays a central role in sensing and integrating nutritional, hormonal, and neural signals that regulate feeding, energy homeostasis, growth, and reproduction, all of which show pronounced sex differences. However, the cellular mechanisms underlying these responses remain poorly understood. We performed snRNA-seq of the mediobasal hypothalamus, focusing on the arcuate nucleus, in female and male mice under different nutritional states. Analysis of 42 cell types revealed that Agrp neurons were most sensitive to nutritional changes, dopaminergic neurons showed strong sex-specific differences, and KNDy neurons were highly responsive to both sex and nutrition. Pomc neurons displayed …

Spatiotemporal Histogenesis Of The Developing Human Cerebellum Reveals Dynamic Layering Of Bergmann Glia, Guanyi He, Simon Du, Henry Tan, Sri Yellampally, Anders W Erickson, Virginia Fernandez, Ferechte Encha-Razavi, Kimberley A Phillips, Christine Haberler, Nicole Amberg, Victor Borrell, Paul A Northcott, Michael D Taylor, Kathleen J Millen, Parthiv Haldipur

Faculty, Staff and Students Publications

Bergmann glia (BG) are a specialized glial population essential for cerebellar development, yet their developmental timeline and molecular identity in the human cerebellum remain poorly understood. Here, we combined detailed histopathological analysis with spatial transcriptomics and single-nucleus RNA sequencing to generate a developmental atlas of human cerebellar BG. Histology revealed that BG emerge around 11 post-conception weeks (PCW), initially serving as a scaffold for Purkinje cells (PCs) migrating into the PC layer of the cerebellar cortex. Following the establishment of a multilayered PC arrangement, BG form a distinct parallel layer separated from the PCs by the lamina dissecans (LD), with …

Syndecan-1-Targeted Therapeutic Antibody Impairs Macropinocytosis And Elicits Antitumor Immunity In Pancreatic Cancer, Zecheng Yang, Madelaine S Theardy, Shuaitong Chen, Yongkun Wei, Mitsunobu Takeda, Yue Zeng, Xiaofei Wang, Jun Yao, Jennifer Li, Prapassorn Thirasastr, Jangho Park, Yangxi Zheng, Long T Vien, Khalida M Wani, Huamin Wang, Sisi Gao, Tim Heffernan, Lawrence Kwong, Ignacio I Wistuba, Laura Bover, Giulio F Draetta, Haoqiang Ying, Wantong Yao

Faculty, Staff and Student Publications

Pancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest malignancies, with a 5-year survival rate of just 13%. While the development and early clinical use of small molecules targeting oncogenic KRAS mutations, key drivers of PDAC, have shown promise, resistance to these targeted therapies remains a significant challenge. We recently identified Syndecan-1 (SDC1), a highly expressed heparan sulfate proteoglycan, as a critical KRAS effector protein that promotes nutrient salvage and tumor growth. Here, we report the development of a human-specific monoclonal antibody (anti-SDC1 mAb) that inhibits PDAC cell proliferation in vitro and suppresses PDAC tumor growth in vivo. Mechanistically, …

Sting-Induced Blood-Brain Barrier Opening Combined With Radiotherapy Potentiates Antitumor Response In A High-Grade Glioma Model, Shashwat Tripathi, Hinda Najem, Lisa Hurley, Ruochen Du, Crismita Dmello, Heba Ali, Kathleen Mccortney, Karl J Habashy, Peng Zhang, Craig M Horbinski, Lara Leoni, Ryan J Avery, Rimas V Lukas, Timothy L Sita, David R Raleigh, Sean Sachdev, Roger Stupp, Maciej S Lesniak, David M Ashley, Daniele Procissi, Michael A Curran, Irina Balyasnikova, Amy B Heimberger

Faculty, Staff and Student Publications

Radiation therapy (RT) is the standard of care for glioblastoma but is not curative. Triggering the cGAS/stimulator of interferon genes (STING) pathway with potent agonists, such as 8803, exerts activity across high-grade glioma preclinical models. To determine if the combination of 8803 with RT warrants consideration in the up-front treatment setting and to clarify the underlying mechanisms of therapeutic activity, C57BL/6J mice harboring intracerebral CT-2A or QPP8v gliomas were treated with RT, intratumoral 8803, or both. The treatment with the combination resulted in 80% long-term survival in the CT-2A model but not in the radiation-resistant QPP8v model. This therapeutic effect …

Targeting Oxalate Production By Combining Enzyme Inhibition And Proteolysis Activation: A Novel Therapeutic Approach For Primary Hyperoxaluria Type 1, Fabio Arias, Sumati Rohilla, Yudibeth Sixto-López, Koral S E Richard, Sandeep Das, Sumit K Anand, Pilar Maria Luque-Navarro, Guillermo Bañuelos-Sanchez, Juan Luis Pacheco-García, Reethika Gade, M Peyton Mckinney, Dhananjay Kumar, Jemiah Maxie, W Rylan Corr, Nilesh Pandey, Harpreet Kaur, Jibin Ding, Lin Tan, Elisha Scott, Hyung Nam, Eyal Gottlieb, A Wayne Orr, Nirav Dhanesha, Arif Yurdagul, Angel L Pey, Francisco Franco-Montalbán, José A Gómez Vidal, Oren Rom, Mónica Díaz-Gavilán

Faculty, Staff and Student Publications

Primary hyperoxaluria type 1 (PH1) is a rare genetic disorder caused by hepatic oxalate overproduction due to alanine-glyoxylate aminotransferase (AGXT) deficiency. Therapeutic strategies targeting glycolate oxidase (GO) and lactate dehydrogenase A (LDHA), key enzymes in glyoxylate metabolism, have shown promise in reducing oxalate burden. However, recently approved siRNA therapies remain limited by high cost, unfavorable pharmacokinetics, and limited global accessibility. We report the development of compound 2, a dual GO/LDHA inhibitor (K i = 390 and 40 nM, respectively) that also promotes hydrophobic tag-mediated autophagic degradation of LDHA. Its efficacy was evaluated in Agxt –/– mice, both in primary …

Molecular Determinant Of Low-Voltage Dependence Of Human Nav1.7 Inactivation Revealed By Efficacy-Based Nav1.7 Selective Inhibitor, Fang Zhao, Chuchu Xi, Jie Li, Kerui Ren, Qinglian Tang, Huaduan Liang, Shilong Yang, Michael X Zhu, Zhengyu Cao

Faculty, Staff and Student Publications

Nav1.7 is a voltage-gated sodium channel (VGSC) subtype predominantly expressed in sensory neurons, amplifying threshold currents. Here, we identify that Uvarigranol D (UGD) suppresses human (h) Nav1.7 with a much greater maximal inhibition than other VGSC subtypes, despite having similar apparent affinities. We demonstrate that Thr1398 determines the greater inhibitory efficacy of UGD, the leftward shift in voltage-dependence and faster inactivation kinetics of hNav1.7. UGD binds to the inactivated state, with Gln360, Ile394, Lys1395, Phe1737, and Tyr1744 being critically involved. Moreover, while UGD suppresses action potentials in both rat dorsal root ganglion neurons and human induced pluripotent stem cell-derived cardiomyocytes, …

Myokine Sirpα Exacerbates Kidney Disease In Diabetes, Jiao Wu, Elisa Russo, Daniela Verzola, Qingtian Li, Helena Zhang, Bhuvaneswari Krishnan, David Sheikh-Hamad, Zhaoyong Hu, William E Mitch, Sandhya S Thomas

Faculty, Staff and Students Publications

Mechanisms responsible for skeletal muscle kidney crosstalk have not been defined. We have determined that a circulating mediator, signal regulatory protein α (SIRPα), impairs intracellular insulin-mediated functions. To elucidate the effect of myokine SIRPα on diabetic kidney disease (DKD), flox mice and muscle-specific (m-specific) SIRPα-KO mice were subjected to an obesity-induced model of diabetes, high-fat diet (HFD; 60%) or insulin-deficient hyperglycemia model, streptozotocin (STZ), and were subsequently exposed to anti-SIRPα monoclonal antibodies. In the obesity-induced diabetic mice, serum SIRPα increased. Genetic deletion of muscle SIRPα protected against obesity and improved intracellular insulin signaling in muscle and adipose tissue, with reduced …

Consensus Paper: Models Of Cerebellar Functions, Shinji Kakei, Andreea C Bostan, Timothy J Ebner, Mohammad Amin Fakharian, Hiroaki Gomi, Xavier Guell, Marie Hemelt, Huu Hoang, Court Hull, Masato Inoue, Takahiro Ishikawa, Masashi Kameda, Mitsuo Kawato, Shigeru Kitazawa, Mario Manto, Javier F Medina, Hiroshi Mitoma, Keiko Ohmae, Shogo Ohmae, Ken-Ichi Okada, Laurentiu S Popa, Jeremy D Schmahmann, Reza Shadmehr, Peter L Strick, Hirokazu Tanaka, Masaki Tanaka, Tadashi Yamazaki

Faculty, Staff and Students Publications

For a long time, from the nineteenth century to most of the twentieth century, the cerebellum was thought to be an organ that regulates movement. Towards the end of the twentieth century, the brain functions associated with the cerebellum began to extend beyond motor control. Now, there is a consensus that the cerebellum is involved not only in motor functions but also in the most basic autonomic functions and the most complex cognitive and emotional functions, with a focus on predictions and internal models. A new functional model of the cerebellum is needed to explain all layers of brain functions …

Ubiquitination-Directed Cytosolic Dna Degradation Governs Cgas-Sting-Mediated Immune Response To Dna Damage, Lei Li, Qi Ye, Jinlu Ma, Zixi Wang, Tianjie Liu, Yuzeshi Lei, Mingming Lu, Jialu Kang, Haohan Xiang, Buyun Li, Shan Xu, Ke Wang, Yule Chen, Jiaqi Chen, Bohan Ma, Wenyue Huang, Mengjiao Cai, Nan Wu, Yanqiang Li, Jiale An, Chongming Jiang, Rui Ye, Jing Liu, Steven H Lin, Yang Gao, Jian Ma, Lei Li

Faculty, Staff and Student Publications

Activation of cGAS-STING signaling in cancer cells requires cytosolic DNA produced by intrinsic or treatment-induced DNA damage. However, clinical efforts to exploit this pathway to improve immunotherapy have yielded limited success, highlighting gaps in understanding the link between DNA damage and immunotherapy. Here, we identify ubiquitination-directed cytosolic DNA degradation as a critical determinant for cGAS-STING activation following DNA damage. Mechanistically, the cytosolic DNA exonuclease TREX1 is degraded by the E3 ubiquitin ligase SPOP but is reversely stabilized by the deubiquitinase USP7. Cancer-associated SPOP mutations or USP7 overexpression elevate TREX1 levels, promoting cytosolic DNA degradation and impairing cGAS-STING-mediated immune activation. Notably, …