Digital Commons Network^™

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, …

Cyp1b1 Mediates Cigarette Smoke-Induced Lipid Accumulation In Alveolar Type 2 Cells, Yin Zhu, Siddhika Gamare, Francesca Polverino, Caroline A Owen, Payaningal R Somanath, Xiaoyun Wang, Duo Zhang

Faculty, Staff and Students Publications

Alterations in lipid profiles have been shown in patients with chronic obstructive pulmonary disease (COPD), but the underlying molecular mechanisms remain unclear. In this study, we aimed to investigate the role of cytochrome P450 family-1 subfamily B member 1 (CYP1B1) in cigarette smoke (CS)-induced lipid accumulation in alveolar type II epithelial (AT2) cells. We observed a steady increase in CYP1B1 protein levels in AT2 cells from COPD patients. Additionally, CS exposure induced CYP1B1 expression in AT2 cells of murine lungs. In vitro, treatment with cigarette smoke extract (CSE) not only upregulated CYP1B1 expression but also triggered lipid accumulation in AT2-like …

Engineered Exosomes With Krasg12d Specific Sirna In Pancreatic Cancer: A Phase I Study With Immunological Correlates, Valerie S Kalluri, Brandon G Smaglo, Krishnan K Mahadevan, Michelle L Kirtley, Kathleen M Mcandrews, Mayela Mendt, Sujuan Yang, Ana S Maldonado, Hikaru Sugimoto, Maria E Salvatierra, Luisa M Solis Soto, Cara Haymaker, Rick Finch, Mihai Gagea, Adam C Fluty, Steven J Ludtke, J Jack Lee, Abhinav K Jain, Gauri Varadhachary, Rachna T Shroff, Anirban Maitra, Elizabeth Shpall, Shubham Pant, Raghu Kalluri

Faculty, Staff and Students Publications

Oncogenic KRAS is amongst the key genetic drivers for initiation and maintenance of pancreatic ductal adenocarcinoma (PDAC). Here, we show that engineered exosomes with KrasG12D specific siRNA (iExoKrasG12D) reveal a biodistribution in pancreas with negligible toxicity in preclinical studies in mice and Rhesus macaques. Clinical testing of iExoKrasG12D in the iEXPLORE (iExoKrasG12D in Pancreatic Cancer) Phase I study employed a non-randomized single-arm classical 3 + 3 dose escalation design (Phase Ia), followed by an accelerated titration design (Phase Ib) (NCT03608631). The primary outcomes included safety, tolerability and target engagement, and the secondary outcomes aimed to assess disease control. …

Development Of A Leucine-Rich Repeat-Containing Protein 15-Targeted Radio-Immunotheranostic Approach To Deplete Pro-Tumorigenic Mechanisms And Immunotherapy Resistance, Claire M Storey, Abbie Hasson, Diane Abou, Daniel Thorek, Et Al.

2020-Current year OA Pubs

Leucine-rich repeat containing 15 (LRRC15) has emerged as an attractive biomarker and target for cancer therapy. Transforming growth factor-β (TGFβ) induces the expression of this plasma membrane protein specifically in aggressive and treatment resistant tumor cells derived from mesenchymal stem cells, with minimal expression observed in non-neoplastic tissues. We have developed a humanized monoclonal antibody, DUNP19, that specifically binds with high affinity to a phylogenetically conserved LRRC15 epitope and is rapidly internalized upon LRRC15 binding. In multiple subcutaneous and orthotopic tumor xenograft mouse models, Lutetium-177 labeled DUNP19 ([

Nanomedicine Targeting Ppar In Adipose Tissue Macrophages Improves Lipid Metabolism And Obesity-Induced Metabolic Dysfunction., Catherine C Applegate, Yifei Kang, Hongping Deng, Donglai Chen, Natalia Y Gonzalez Medina, Yuxiao Cui, Yujun Feng, Chia-Wei Kuo, Sayyed Hamed Shahoei, Hannah Kim, Hashni Epa Vidana Gamage, Matthew A Wallig, Erik R Nelson, Kelly S Swanson, Andrew M Smith

Faculty Research 2025

Excess body fat leads to an overabundance of adipose tissue macrophages (AT MΦs) with altered phenotypes that play pathogenic roles in obesity comorbidities including diabetes and cancer. Peroxisome proliferator-activated receptors (PPARs) are leading targets to modulate AT MΦ phenotype. Here, we developed a dextran-based nanomedicine that delivers PPARα/γ agonists to AT MΦs and improves obesity and diabetic phenotypes in vivo. Within 1 week of treatment, AT MΦs decreased and became lipid laden, while extracellular vesicles secreted from AT decreased and reduced in lipid content. Within 2 weeks, glucose tolerance returned to levels of lean controls, followed by weight loss and …

Distinct Intrinsic And Extrinsic Factors Differentially Regulate Skeletal Stem Cells In Calvaria Versus Long Bones During Bone Regeneration, Jea Solidum, Kohei Yamasaki, Youngjae Jeong, Laura Ortinau, Francisco Heralde, Dongsu Park

Faculty, Staff and Students Publications

Calvarial suture skeletal stem cells (Su-SSCs) are a distinct stem cell population for craniofacial bone formation by intramembranous ossification, compared to long bone periosteal SSCs (LB-PSSCs) with endochondral (osteochondrogenic) ossification. However, whether SSC intrinsic or extrinsic factors affect their differentiation process has not been well elucidated. Here, using an inducible Prx1-CreER-EGFP+/−;Rosa26-tdTomato mouse model, we observed that endogenous Prx1+ Su-SSCs and their orthotopic transplantation into calvarial injury do not form cartilage intermediates at the injury sites, while the transplantation of Prx1+ LB-PSSCs into LB injury induces osteochondrogenic differentiation, respectively. However, the heterotopic transplantation of Prx1+ Su-SSCs (Su-SSCs …

Aging In Mice Alters Regionally Enriched Striatal Astrocytes, Kay E Linker, Violeta Duran-Laforet, Matthias Ollivier, Xinzhu Yu, Dorothy P Schafer, Baljit S Khakh

Faculty, Staff and Student Publications

Aging affects multiple organs and within the brain drives distinct molecular changes across different cell types. The striatum encodes motor behaviors that decline with age, but our understanding of how cells within the striatum change remains incomplete. Using single-cell RNA sequencing from young and aged mice we identify molecularly distinct astrocyte subtypes. We show that astrocytes change significantly with age, exhibiting downregulation of genes, reduced diversity, and a shift to more homogenous inflammatory transcriptomic profiles. By exploring where striatal astrocyte subtypes are located with single-cell resolution, we map astrocytes enriched in dorsal, medial, and ventral striatum. Age increases inflammatory marker …

Lysosomal Lrrc8 Complex Impacts Lysosomal Ph, Morphology, And Systemic Glucose Metabolism, Ashutosh Kumar, Yonghui Zhao, Litao Xie, Rahul Chadda, John D Tranter, Ryan T Mikami, Nihil Abraham, Juan Hong, Ethan Feng, David R Rawnsley, Haiyan Liu, Gretchen Meyer, Abhinav Diwan, Rajan Sah, Et Al.

2020-Current year OA Pubs

The lysosome integrates anabolic signaling and nutrient sensing to regulate intracellular growth pathways. The leucine-rich repeat-containing 8 (LRRC8) channel complex forms a lysosomal anion channel and regulates PI3K-AKT-mTOR signaling, skeletal muscle differentiation, growth, and systemic glucose metabolism. Here, we define the endogenous LRRC8 subunits localized to a subset of lysosomes in differentiated myotubes. We show that LRRC8A affects leucine-stimulated mTOR; lysosome size; number; pH; expression of lysosomal proteins LAMP2, P62, and LC3B; and lysosomal function. Mutating an LRRC8A lysosomal targeting dileucine motif sequence (LRRC8A-L706A;L707A) in myotubes recapitulates the abnormal AKT signaling and altered lysosomal morphology and pH observed in LRRC8A …

Site-1 Protease Is A Negative Regulator Of Sarcolipin Promoter Activity, Isha Sharma, Meredith O Kelly, Katelyn Hanners, Ella S Shin, Muhammad G Mousa, Shelby Ek, Gretchen A Meyer, Rita T Brookheart

2020-Current year OA Pubs

The timed contraction and relaxation of myofibers in tissues such as the heart and skeletal muscle occur via the tightly regulated movement of calcium ions into and out of the sarcoplasmic reticulum (SR). In skeletal muscle, this phenomenon enables humans to exercise, perform day-to-day tasks, and to breathe. Sarcolipin, a small regulatory protein, prevents calcium ions from entering the SR by binding to and inhibiting SERCA, contributing to myofiber contraction. Disruptions in sarcolipin (SLN) expression are implicated in the pathophysiology of obesity and musculoskeletal disease. However, the mechanisms regulating sarcolipin expression are not clearly understood. We recently showed that site-1 …

Sars-Cov-2 Nsp13 Interacts With Tead To Suppress Hippo-Yap Signaling, Fansen Meng, Jong Hwan Kim, Chang-Ru Tsai, Jeffrey D Steimle, Jun Wang, Yufeng Shi, Rich G Li, Bing Xie, Vaibhav Deshmukh, Shijie Liu, Xiao Li, James F Martin

Faculty, Staff and Students Publications

The Hippo pathway controls organ development, homeostasis, and regeneration primarily by modulating YAP/TEAD-mediated gene expression. Although emerging studies report Hippo-YAP dysfunction after viral infection, it is largely unknown in the context of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, we analyzed RNA sequencing data from human-induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) and SARS-CoV-2-infected human lung samples, and observed a decrease in YAP target gene expression. In screening SARS-CoV-2 nonstructural proteins, we found that nonstructural protein 13 (NSP13), a conserved coronavirus helicase, inhibits YAP transcriptional activity independent of the upstream Hippo kinases LATS1/2. Consistently, introducing NSP13 into mouse cardiomyocytes suppresses …

Adsl Deficiency Is A Secondary Mitochondrial Disease Affecting Organelle Homeostasis And Erk2/Akt Signaling In A Linear Genotype-Phenotype Relation, Matteo Bordi, Beatrice Testa, Claudia Compagnucci, Fiorella Colasuonno, Francesca Cipressa, Elisabetta Betterini, Andrea Mancini, Claudia Carsetti, Illari Salvatori, Caterina Ferraina, Ming Yang, Rossella De Cegli, Eugenio Del Prete, Chiara Veroni, Salvatore Rizza, Sofia Mauri, Elena Ziviani, Marina Macchiaiolo, Davide Vecchio, Filippo Maria Panfili, Teresa Rizza, Gerrit Weber, Rosalba Carrozzo, Alberto Ferri, Silvia Campello, Andrea Ballabio, Christian Frezza, Gianluca Cestra, Marco Tartaglia, Andrea Bartuli, Francesco Cecconi

Duncan NRI Faculty and Staff Publications

Adenylosuccinate lyase deficiency (ADSLd) is a rare autosomal recessive purine metabolism disorder with several clinical manifestations. While toxic substrate accumulation is a known hallmark, no additional molecular mechanisms have been established. Here, we show that ADSLd is associated with mitochondrial dysfunction, including increased fragmentation, impaired respiration, and reduced ATP production. The severity of mitochondrial impairment correlates with ADSLd pathology, especially in mitochondria-dependent tissues. We also identify defects in mitochondrial dynamics and transport linked to ERK2 and AKT suppression. Notably, overexpressing constitutively active ERK2 or supplementing purine intermediates partially rescues the mitochondrial phenotype. These findings suggest an alternative disease mechanism and …

Rna/Dna-Binding Protein Tdp43 Regulates Dna Mismatch Repair Genes With Implications For Genome Stability, Vincent E Provasek, Albino Bacolla, Suganya Rangaswamy, Manohar Kodavati, Joy Mitra, Issa O Yusuf, Vikas H Malojirao, Velmarini Vasquez, Gavin W Britz, Guo-Min Li, Zuoshang Xu, Sankar Mitra, Ralph M Garruto, John A Tainer, Muralidhar L Hegde

Faculty, Staff and Student Publications

TDP43 is an RNA/DNA-binding protein increasingly recognized for its role in neurodegenerative conditions, including amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). As characterized by its aberrant nuclear export and cytoplasmic aggregation, TDP43 proteinopathy is a hallmark feature in over 95% of ALS/FTD cases, leading to detrimental cytosolic aggregates and a reduction in nuclear functionality in neurons. Building on our prior work linking TDP43 proteinopathy to the accumulation of DNA double-strand breaks (DSBs) in neurons, the present investigation uncovers a novel regulatory relationship between TDP43 and DNA mismatch repair (MMR) gene expression. Here, we show that TDP43 depletion or overexpression …

Humanization Of Cd47 Enables Development Of Functional Human Neutrophils Via Postirradiation Remodeling Of The Bone Marrow, Esen Sefik, Liang Shan, Et Al.

2020-Current year OA Pubs

Murine and human immune systems differ significantly, particularly within the myeloid lineage. Humanized mice, generated by transplanting human hematopoietic stem, progenitor cells into genetically modified mice, are invaluable to study human immune development and function in vivo. However, a major limitation of current models is suboptimal myelopoiesis, particularly lack of functional human neutrophils, hampering the modeling of human immune responses and chronic diseases. Here, we describe a humanized mouse model, named MaGIC for genes replaced, in the

Blue-Shifted Ancyromonad Channelrhodopsins For Multiplex Optogenetics, Elena G Govorunova, Oleg A Sineshchekov, Hai Li, Yueyang Gou, Hongmei Chen, Shuyuan Yang, Yumei Wang, Stephen Mitchell, Alyssa Palmateer, Leonid S Brown, François St-Pierre, Mingshan Xue, John L Spudich

Duncan NRI Faculty and Staff Publications

Light-gated ion channels from protists (channelrhodopsins or ChRs) are optogenetic tools widely used for controlling neurons and cardiomyocytes. Multiplex optogenetic applications require spectrally separated molecules, which are difficult to engineer without disrupting channel function. Scanning numerous sequence databases, we identified three naturally blue-shifted ChRs from ancyromonads. They form a separate branch on the phylogenetic tree and contain residue motifs characteristic of anion ChRs (ACRs). However, only two conduct chloride, whereas the closely related Nutomonas longa homolog generates inward cation currents in mammalian cells under physiological conditions, significantly exceeding those by previously known tools with similar spectral maxima (peak absorption at …

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.

Rapid Mapping Of Spinal And Supraspinal Connectome Via Self-Targeting Glucose-Based Carbon Dots, Yasin B. Seven, Elif S. Seven, Emel Kirbas Cilingir, Komal Parikh, Mehmet Aydin, Edward K. Luca, Jayakrishnan Nair, Roger M. Leblanc

Department of Physical Therapy Faculty Papers

The spinal cord is a highly dynamic network, playing significant roles in the vital functions of the brain. Disorders of the spinal cord, such as spinal cord injury and amyotrophic lateral sclerosis (ALS), are associated with neurodegeneration, often resulting in morbidity and mortality. The blood-brain barrier (BBB) poses a major challenge to imaging and therapeutic agents because less than 2% of small-molecule drugs and almost no large-molecule drugs can cross the BBB. Furthermore, spatial spectroscopy studies have shown highly heterogeneous BBB crossing with significant accumulation at the unintended brain regions. Thus, targeting systems that can cross the BBB at the …

Galntl5 Binds Galnac And Is Required For Migration Through The Uterotubal Junction And Sperm-Zona Pellucida Binding, Taichi Noda, Reika Uriu, Daisuke Mashiko, Hina Shinohara, Yongcun Qu, Ayumu Taira, Ryan M Matzuk, Duri Tahala, Motochika Nakano, Kimi Araki, Zhifeng Yu, Ying Zhang, Martin M Matzuk, Masahito Ikawa

Faculty, Staff and Students Publications

More than 20 genes expressed in the male reproductive tract have been identified as essential factors for sperm migration to and through the utero-tubal junction (UTJ), and they are divided into ADAM3-dependent and ADAM3-independent pathways. In parallel, sperm having UTJ migration defects also show impaired binding to the zona pellucida (ZP). Herein, we demonstrate that knockout of Galntl5, encoding a sperm surface protein, causes impaired sperm binding with the UTJ and ZP, and null males have severe infertility. GALNTL5 appreciably disappears in sperm lacking Adam3 or Lypd4, required for ADAM3-dependent and ADAM3-independent pathways, and GALNTL5 binds to N …

Galntl5 Binds Galnac And Is Required For Migration Through The Uterotubal Junction And Sperm-Zona Pellucida Binding, Taichi Noda, Reika Uriu, Daisuke Mashiko, Hina Shinohara, Yongcun Qu, Ayumu Taira, Ryan M Matzuk, Duri Tahala, Motochika Nakano, Kimi Araki, Zhifeng Yu, Ying Zhang, Martin M Matzuk, Masahito Ikawa

Faculty, Staff and Students Publications

Objective: To review the global impact of the COVID-19 pandemic on stroke care-metrics and report data from a health system in Houston.

Methods: We performed a meta-analysis of the published literature reporting stroke admissions, intracerebral hemorrhage (ICH) cases, number of thrombolysis (tPA) and thrombectomy (MT) cases, and time metrics (door to needle, DTN; and door to groin time, DTG) during the pandemic compared to prepandemic period. Within our hospital system, between January-June 2019 and January-June 2020, we compared the proportion of stroke admissions and door to tPA and MT times.

Results: A total of 32,640 stroke admissions from 29 studies …

Elevated Nr2f1 Underlies The Persistence Of Invasive Disease After Treatment Of Braf-Mutant Melanoma, Manoela Tiago, Timothy J Purwin, Casey D Stefanski, Renaira Oliveira Da Silva, Mitchell E Fane, Yash Chhabra, Jelan I Haj, Jessica Lf Teh, Rama Kadamb, Weijia Cai, Sheera R Rosenbaum, Vivian Chua, Nir Hacohen, Michael A Davies, Jessie Villanueva, Inna Chervoneva, Ashani T Weeraratna, Dan A Erkes, Claudia Capparelli, Julio A Aguirre-Ghiso, Andrew E Aplin

Faculty, Staff and Student Publications

Despite the success of targeted inhibitors in cutaneous melanoma, therapeutic responses are limited by the aged tumor microenvironment and drug-tolerant residual cells. Given the similarities between drug tolerance and cellular dormancy, we studied the dormancy marker, nuclear receptor subfamily 2 group F member 1 (NR2F1), in response to BRAF-V600E inhibitors (BRAFi) plus MEK inhibitors (MEKi) in BRAF-mutant melanoma models. Transcriptomic analysis of melanoma patient samples treated with BRAFi + MEKi showed increased NR2F1. NR2F1 was highly expressed in the drug-tolerant invasive cell state of minimal residual disease in patient-derived and mouse-derived xenografts on BRAFi + MEKi. NR2F1 over-expression was sufficient …

Notch1 Reverses Immune Suppression In Small Cell Lung Cancer Through Reactivation Of Sting, Yoo Sun Kim, Haobin Chen, Et Al.

2020-Current year OA Pubs

Downregulation of antigen presentation and lack of immune infiltration are defining features of small cell lung cancer (SCLC), limiting response to immune checkpoint blockade (ICB). While a high-MHC class I, immune-inflamed subset benefits from ICB, underlying mechanisms of immune response in SCLC have yet to be elucidated. Here we show that in the IMpower133 clinical trial, high, but not low, NOTCH1 expression was significantly associated with longer survival with the addition of ICB to chemotherapy among approximately 80% of SCLC patients with NE-enriched tumors (ASCL1-enriched, HR 0.39, P = 0.0012; NEUROD1-enriched, HR 0.44, P = 0.024). Overexpression or pharmacologic activation …

Developmental Transformations Of Purkinje Cells Tracked By Dna Electrokinetic Mobility, Cheryl Brandenburg, Garrett W Crutcher, Andrea J Romanowski, Sarah G Donofrio, Lita R Duraine, Richard N A Owusu-Mensah, Benjamin H Cooper, Izumi Sugihara, Gene J Blatt, Roy V Sillitoe, Alexandros Poulopoulos

Duncan NRI Faculty and Staff Publications

Brain development begins with neurogenesis in progenitor zones and ends with expansive, intricately-patterned cellular diversity in the adult brain. We took advantage of bioelectric interactions between DNA and embryonic tissue to perform "stereo-tracking," a developmental targeting strategy that differentially labels cells at different depths within progenitor zones. This 3D labeling was achieved by delivery of plasmids with distinct electrokinetic mobilities in utero. We applied stereo-tracking with light sheet imaging in the cerebellum and identified that Purkinje cells follow embryonically committed developmental trajectories, linking distinct progenitor zone subfields to the mature topography of the cerebellar cortex. We additionally identified an unexpected …

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 …

A Novel Sialylation Pathway Mediated By Extracellular Vesicles In Aggressive Prostate Cancer, Camila A. Bach, Md Niamat Hossain, Ishan J. Chaudhari, Cecilia E. Verrillo, Nicole M. Naranjo, Isabella Amoroso, Anna Testa, Samuel Sey, W. Kevin Kelly, Susan L. Bellis, Aurelio Lorico, Ada G. Blidner, Gabriel A. Rabinovich, Lucia R. Languino

Department of Pharmacology, Physiology, and Cancer Biology Faculty Papers

Altered cell surface glycosylation is a hallmark of cancer; among aberrant glycan structures, hypersialylated proteins contribute to disease progression. The enzyme ST6 β-galactoside α2,6-sialyltransferase 1 (ST6GAL1) mediates α2,6-linked sialylation of N-glycosylated proteins and is upregulated in many cancers, including prostate cancer (PrCa). We propose that ST6GAL1 may be released by cancer cells in small extracellular vesicles (sEVs) in the PrCa tumor microenvironment to potentially modulate cell surface sialylation in recipient cells. We isolated sEVs from PrCa cells by density gradient separation and characterized them by nanoparticle tracking analysis using ZetaView and immunoblotting analysis. We identified ST6GAL1 in both its membrane-bound …

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 …

Loss Of Ptdss1 In Tumor Cells Improves Immunogenicity And Response To Anti-Pd-1 Therapy, Jielin Liu, Shelley Herbrich, Sreyashi Basu, Yulong Chen, Ashwat Nagarajan, Swetha Anandhan, Sangeeta Goswami, Liangwen Xiong, Baoxiang Guan, Padmanee Sharma

Faculty, Staff and Student Publications

PTDSS1 (phosphatidylserine synthase 1) encodes an enzyme that facilitates production of phosphatidylserine (PS), which mediates a global immunosuppressive signal. Here, based on in vivo CRISPR screen, we identified PTDSS1 as a target to improve anti-PD-1 therapy. Depletion of Ptdss1 in tumor cells increased expression of interferon-γ (IFN-γ)-regulated genes, including B2m, Cxcl9, Cxcl10, and Stat1, even in the absence of IFN-γ stimulation in vitro. Loss of Ptdss1 in tumor cells also led to increased expression of MHC-I, enhanced cytotoxicity of CD8+ T cells, and increased frequency of an iNOS+ myeloid subset. A gene signature derived from the …

Retinoid-X-Receptor As A Mediator Of Poststroke Recovery By Reversing Age-Associated Phenotypes Of Microglia/Hematogenous Macrophages, Shun-Ming Ting, Xiurong Zhao, Guanghua Sun, Mercedes Ricote, Jaroslaw Aronowski

Faculty, Staff and Student Publications

After stroke, microglia and hematogenous macrophages, together referred to as MΦ, clear dead cells and cellular debris in the infarcted brain through phagocytosis as an essential part of the recovery process. However, the phagocytic capability of MΦ declines with age. Furthermore, aged MΦ become overactivated in response to stroke, enhancing secondary brain injury. In this study, we demonstrated that by reversing the age-related dysfunctions in MΦ through activating the retinoid X receptor (RXR), the recovery after stroke in the aged brain could be improved. Using RNA-sequencing, we compared the transcriptomes between MΦ isolated from the brains of young and aged …

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 …

Testis Expressed 50 Is Essential For Maintaining Sperm Acrosome Integrity During Epididymal Transit, Saori Haga, Kaori Nozawa, Ferheen Abbasi, Katarzyna Kent, Naoko Nagasawa, Tsutomu Endo, Haruhiko Miyata, Masahito Ikawa, Martin M Matzuk, Yoshitaka Fujihara

Faculty, Staff and Students Publications

In mammals, sperm formation is completed in the seminiferous tubules within the testis, and sperm maturation occurs during the epididymal transit of the spermatozoa. Sperm morphology drastically changes when abnormal spermatozoa migrate from the testis to the epididymis. Detailed molecular mechanisms for sperm survival in the epididymis have not been determined yet. Globozoospermia is a cause of male infertility and is characterized by round-headed spermatozoa without acrosomes, an abnormal sperm nuclear membrane, and sperm midpiece defects. Testis expressed 50 (Tex50) is a testis-enriched gene that is expressed in mice and humans. Using CRISPR-Cas9, we generated Tex50 knockout (KO) …

Computationally Resolved Neuroprogenitor Cell Biomarkers Associate With Human Disorders, Gerarda Cappuccio, William T Choi, Fatih Semerci, Jill A Rosenfeld, Toni Claire Tacorda, Guantong Qi, Anthony W Zoghbi, Yi Zhong, Hu Chen, Pengfei Liu, Zhandong Liu, Mirjana Maletić-Savatić

Duncan NRI Faculty and Staff Publications

Adult hippocampal neurogenesis, the process of generating new neurons, relies on a rare population of neural stem and progenitor cells (NPCs) within the dentate gyrus complex microenvironment. Discovering the specific genes that define these cells is vital yet challenging due to overlapping expression patterns, limiting detection of rare cell populations using traditional approaches. By employing the computational digital sorting algorithm (DSA) that deconvolves complex gene expression data based on pattern recognition, we identified 129 genes enriched in murine NPCs. We validated these genes against published single-cell RNA sequencing (scRNA-seq) data and discovered that 25 human orthologs were known to cause …

Therapeutic Restoration Of Mitochondria-Endoplasmic Reticulum Cross Talk For Osteoarthritis, Mingzhuang Hou, Yifan Ma, Yaoge Deng, Yubin Wu, Yanrun Zhu, Yang Liu, Xiaoping Li, Lili Yu, Zirui He, Yifan Wang, Shiyan Dong, Xiaowei Xia, Jianfeng Yu, Chenqi Yu, Kang Kang, Yingjie Lu, Lili Sun, Betty Y S Kim, Yuan Yuan, Yijian Zhang, Wen Jiang, Xuesong Zhu

Faculty, Staff and Student Publications

Osteoarthritis is a prevalent joint disease in the aging population. The hallmark of osteoarthritis is the degeneration of the joint cartilage, characterized by changes in chondrocytes including mitochondrial dysfunction. However, the precise mechanisms of how this affects chondrocyte homeostasis and whether such processes can be explored as therapeutic targets for osteoarthritis remain unclear. Here, we show that impaired mitochondrial function and disrupted cartilage matrix metabolism due to loss of mitofusin-2 (MFN2) expression in chondrocytes leads to the development of osteoarthritis. Sirtuin-3 (SIRT3), a key regulator of mitochondrial function, plays a critical role in modulating MFN2 to restore mitochondrial dynamics, reduce …