Digital Commons Network^™

Zinc Treatment Reverses And Anti-Zn-Regulated Mirs Suppress Esophageal Carcinomas In Vivo, Louise Fong, Kay Huebner, Ruiyan Jing, Karl Smalley, Christopher R Brydges, Oliver Fiehn, John Farber, Carlo M Croce

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Esophageal squamous cell carcinoma (ESCC) is a deadly disease with few prevention or treatment options. ESCC development in humans and rodents is associated with Zn deficiency (ZD), inflammation, and overexpression of oncogenic microRNAs: miR-31 and miR-21. In a ZD-promoted ESCC rat model with upregulation of these miRs, systemic antimiR-31 suppresses the miR-31-EGLN3/STK40-NF-κB-controlled inflammatory pathway and ESCC. In this model, systemic delivery of Zn-regulated antimiR-31, followed by antimiR-21, restored expression of tumor-suppressor proteins targeted by these specific miRs: STK40/EGLN3 (miR-31), PDCD4 (miR-21), suppressing inflammation, promoting apoptosis, and inhibiting ESCC development. Moreover, ESCC-bearing Zn-deficient (ZD) rats receiving Zn medication showed a 47% …

Effects Of Prenatal Pesticide Exposure On The Fetal Brain And Placenta Transcriptomes In A Rodent Model, Corina Lesseur, Kirtan Kaur, Sean D Kelly, Karen Hermetz, Randy Williams, Ke Hao, Carmen J Marsit, W Michael Caudle, Jia Chen

Faculty, Staff and Student Publications

Organophosphate and pyrethroid pesticides are among the most extensively used insecticides worldwide. Prenatal exposures to both classes of pesticides have been linked to a wide range of neurobehavioral deficits in the offspring. The placenta is a neuroendocrine organ and the crucial regulator of the intrauterine environment; early-life toxicant exposures could impact neurobehavior by disrupting placental processes. Female C57BL/6 J mice were exposed via oral gavage to an organophosphate, chlorpyrifos (CPF) at 5 mg/kg, a pyrethroid, deltamethrin (DM), at 3 mg/kg, or vehicle only control (CTL). Exposure began two weeks before breeding and continued every three days until euthanasia at gestational …

Multiple And Consecutive Genome Editing Using I-Gonad And Breeding Enrichment Facilitates The Production Of Genetically Modified Mice, Carolina R Melo-Silva, Cory J Knudson, Lingjuan Tang, Samita Kafle, Lauren E. Springer, Jihae Choi, Christopher M. Snyder, Yajing Wang, Sangwon V. Kim, Luis J. Sigal

Department of Microbiology and Immunology Faculty Papers

Genetically modified (GM) mice are essential tools in biomedical research. Traditional methods for generating GM mice are expensive and require specialized personnel and equipment. The use of clustered regularly interspaced short palindromic repeats (CRISPR) coupled with improved-Genome editing via Oviductal Nucleic Acids Delivery (i-GONAD) has highly increased the feasibility of producing GM mice in research laboratories. However, genetic modification in inbred mouse strains of interest such as C57BL/6 (B6) is still challenging because of their low fertility and embryo fragility. We have successfully generated multiple novel GM mouse strains in the B6 background while attempting to optimize i-GONAD. We found …

Dimeric P53 Mutant Elicits Unique Tumor-Suppressive Activities Through An Altered Metabolic Program, Jovanka Gencel-Augusto, Xiaoping Su, Yuan Qi, Elizabeth M Whitley, Vinod Pant, Shunbin Xiong, Vrutant Shah, Jerome Lin, Encarnacion Perez, Marta L Fiorotto, Iqbal Mahmud, Abhinav K Jain, Philip L Lorenzi, Nicholas E Navin, Ellen R Richie, Guillermina Lozano

Faculty, Staff and Student Publications

Cancer-related alterations of the p53 tetramerization domain (TD) abrogate wild-type (WT) p53 function. They result in a protein that preferentially forms monomers or dimers, which are also normal p53 states under basal cellular conditions. However, their physiologic relevance is not well understood. We have established in vivo models for monomeric and dimeric p53, which model Li-Fraumeni syndrome patients with germline p53 TD alterations. p53 monomers are inactive forms of the protein. Unexpectedly, p53 dimers conferred some tumor suppression that is not mediated by canonical WT p53 activities. p53 dimers upregulate the PPAR pathway. These activities are associated with lower prevalence …

A Parathyroid Hormone/Salt-Inducible Kinase Signaling Axis Controls Renal Vitamin D Activation And Organismal Calcium Homeostasis, Sung-Hee Yoon, Mark B Meyer, Carlos Arevalo, Murat Tekguc, Chengcheng Zhang, Jialiang S Wang, Christian D Castro Andrade, Katelyn Strauss, Tadatoshi Sato, Nancy A Benkusky, Seong Min Lee, Rebecca Berdeaux, Marc Foretz, Thomas B Sundberg, Ramnik J Xavier, Charles H Adelmann, Daniel J Brooks, Anthony Anselmo, Ruslan I Sadreyev, Ivy A Rosales, David E Fisher, Navin Gupta, Ryuji Morizane, Anna Greka, J Wesley Pike, Michael Mannstadt, Marc N Wein

Faculty, Staff and Student Publications

The renal actions of parathyroid hormone (PTH) promote 1,25-vitamin D generation; however, the signaling mechanisms that control PTH-dependent vitamin D activation remain unknown. Here, we demonstrated that salt-inducible kinases (SIKs) orchestrated renal 1,25-vitamin D production downstream of PTH signaling. PTH inhibited SIK cellular activity by cAMP-dependent PKA phosphorylation. Whole-tissue and single-cell transcriptomics demonstrated that both PTH and pharmacologic SIK inhibitors regulated a vitamin D gene module in the proximal tubule. SIK inhibitors increased 1,25-vitamin D production and renal Cyp27b1 mRNA expression in mice and in human embryonic stem cell–derived kidney organoids. Global- and kidney-specific Sik2/Sik3 mutant mice showed Cyp27b1 upregulation, …

Enhancing Oral Delivery Of Plant-Derived Vesicles For Colitis, Yuan Liu, Adrian Lankenau Ahumada, Emine Bayraktar, Paul Schwartz, Mamur Chowdhury, Sixiang Shi, Manu M Sebastian, Htet Khant, Natalia De Val, Nazende Nur Bayram, Guodong Zhang, Thanh Chung Vu, Zuliang Jie, Nicholas B Jennings, Cristian Rodriguez-Aguayo, Jody Swain, Elaine Stur, Lingegowda S Mangala, Yutuan Wu, Supriya Nagaraju, Brooke Ermias, Chun Li, Gabriel Lopez-Berestein, Janet Braam, Anil K Sood

Faculty, Staff and Student Publications

Plant-derived vesicles (PDVs) are attractive for therapeutic applications, including as potential nanocarriers. However, a concern with oral delivery of PDVs is whether they would remain intact in the gastrointestinal tract. We found that 82% of cabbage PDVs were destroyed under conditions mimicking the upper digestive tract. To overcome this limitation, we developed a delivery method whereby lyophilized Eudragit S100-coated cabbage PDVs were packaged into a capsule (Cap-cPDVs). Lyophilization and suspension of PDVs did not have an appreciable impact on PDV structure, number, or therapeutic effect. Additionally, packaging the lyophilized Eudragit S100-coated PDVs into capsules allowed them to pass through the …

The Melanocortin Action Is Biased Toward Protection From Weight Loss In Mice, Hongli Li, Yuanzhong Xu, Yanyan Jiang, Zhiying Jiang, Joshua Otiz-Guzman, Jessie C Morrill, Jing Cai, Zhengmei Mao, Yong Xu, Benjamin R Arenkiel, Cheng Huang, Qingchun Tong

Faculty, Staff and Student Publications

The melanocortin action is well perceived for its ability to regulate body weight bidirectionally with its gain of function reducing body weight and loss of function promoting obesity. However, this notion cannot explain the difficulty in identifying effective therapeutics toward treating general obesity via activation of the melanocortin action. Here, we provide evidence that altered melanocortin action is only able to cause one-directional obesity development. We demonstrate that chronic inhibition of arcuate neurons expressing proopiomelanocortin (POMC) or paraventricular hypothalamic neurons expressing melanocortin receptor 4 (MC4R) causes massive obesity. However, chronic activation of these neuronal populations failed to reduce body weight. …

Sleep-Wake Patterns Are Altered With Age, Prdm13 Signaling In The Dmh, And Diet Restriction In Mice, Shogo Tsuji, Cynthia S Brace, Nicholas Rensing, Michael Wong, Shin-Ichiro Imai, Et Al.

2020-Current year OA Pubs

Old animals display significant alterations in sleep-wake patterns such as increases in sleep fragmentation and sleep propensity. Here, we demonstrated that PR-domain containing protein 13 (Prdm13)+ neurons in the dorsomedial hypothalamus (DMH) are activated during sleep deprivation (SD) in young mice but not in old mice. Chemogenetic inhibition of Prdm13+ neurons in the DMH in young mice promotes increase in sleep attempts during SD, suggesting its involvement in sleep control. Furthermore, DMH-specific

Mapping The Metabolic Reprogramming Induced By Sodium-Glucose Cotransporter 2 Inhibition, Aviram Kogot-Levin, Yael Riahi, Ifat Abramovich, Ofri Mosenzon, Bella Agranovich, Liat Kadosh, Rachel Ben-Haroush Schyr, Doron Kleiman, Liad Hinden, Erol Cerasi, Danny Ben-Zvi, Ernesto Bernal-Mizrachi, Joseph Tam, Eyal Gottlieb, Gil Leibowitz

Faculty, Staff and Student Publications

Diabetes is associated with increased risk for kidney disease, heart failure, and mortality. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) prevent these adverse outcomes; however, the mechanisms involved are not clear. We generated a roadmap of the metabolic alterations that occur in different organs in diabetes and in response to SGLT2i. In vivo metabolic labeling with 13C-glucose in normoglycemic and diabetic mice treated with or without dapagliflozin, followed by metabolomics and metabolic flux analyses, showed that, in diabetes, glycolysis and glucose oxidation are impaired in the kidney, liver, and heart. Treatment with dapagliflozin failed to rescue glycolysis. SGLT2 inhibition increased glucose oxidation …

Cd73-Dependent Adenosine Signaling Through Adora2b Drives Immunosuppression In Ductal Pancreatic Cancer, Erika Y Faraoni, Kanchan Singh, Vidhi Chandra, Olivereen Le Roux, Yulin Dai, Ismet Sahin, Baylee J O'Brien, Lincoln N Strickland, Le Li, Emily Vucic, Amanda N Warner, Melissa Pruski, Trent Clark, George Van Buren, Nirav C Thosani, John S Bynon, Curtis J Wray, Dafna Bar-Sagi, Kyle L Poulsen, Lana A Vornik, Michelle I Savage, Shizuko Sei, Altaf Mohammed, Zhongming Zhao, Powel H Brown, Tingting Mills, Holger K Eltzschig, Florencia Mcallister, Jennifer M Bailey-Lundberg

Faculty, Staff and Student Publications

The microenvironment that surrounds pancreatic ductal adenocarcinoma (PDAC) is profoundly desmoplastic and immunosuppressive. Understanding triggers of immunosuppression during the process of pancreatic tumorigenesis would aid in establishing targets for effective prevention and therapy. Here, we interrogated differential molecular mechanisms dependent on cell of origin and subtype that promote immunosuppression during PDAC initiation and in established tumors. Transcriptomic analysis of cell-of-origin-dependent epithelial gene signatures revealed that Nt5e/CD73, a cell-surface enzyme required for extracellular adenosine generation, is one of the top 10% of genes overexpressed in murine tumors arising from the ductal pancreatic epithelium as opposed to those rising from acinar cells. …

Necrotizing Enterocolitis In Premature Infants-A Defect In The Brakes? Evidence From Clinical And Animal Studies., Venkatesh Sampath, Maribel Martinez, Michael Caplan, Mark A. Underwood, Alain Cuna

Manuscripts, Articles, Book Chapters and Other Papers

A key aspect of postnatal intestinal adaptation is the establishment of symbiotic relationships with co-evolved gut microbiota. Necrotizing enterocolitis (NEC) is the most severe disease arising from failure in postnatal gut adaptation in premature infants. Although pathological activation of intestinal Toll-like receptors (TLRs) is believed to underpin NEC pathogenesis, the mechanisms are incompletely understood. We postulate that unregulated aberrant TLR activation in NEC arises from a failure in intestinal-specific mechanisms that tamponade TLR signaling (the brakes). In this review, we discussed the human and animal studies that elucidate the developmental mechanisms inhibiting TLR signaling in the postnatal intestine (establishing the …

The Effect Of A Pharmaceutical Ghrelin Agonist On Lifespan In C57bl/6j Male Mice: A Controlled Experiment, Kathryn A Kaiser, Inga Kadish, Thomas Van Groen, Daniel L Smith, Stephanie Dickinson, Beate Henschel, Erik S Parker, Andrew W Brown, David B Allison

Children’s Nutrition Research Center Staff Publications

Interventions for animal lifespan extension like caloric restriction (CR) have identified physiologic and biochemical pathways related to hunger and energy-sensing status as possible contributors, but mechanisms have not been fully elucidated. Prior studies using ghrelin agonists show greater food intake but no effect on lifespan in rodent models. This experiment in male C57BL/6J mice tested the influence of ghrelin agonism for perceived hunger, in the absence of CR, on longevity. Mice aged 4 weeks were allowed to acclimate for 2 weeks prior to being assigned (N = 60/group). Prior to lights off daily (12:12 cycle), animals were fed a ghrelin …

Insulin-Like Growth Factor-1 Supplementation Promotes Brain Maturation In Preterm Pigs, Line I Christiansen, Bo Holmqvist, Xiaoyu Pan, Kristine Holgersen, Sandy E H Lindholm, Nicole L Henriksen, Douglas G Burrin, David Ley, Thomas Thymann, Per Torp Sangild, Stanislava Pankratova

Faculty, Staff and Students Publications

Very preterm infants show low levels of insulin-like growth factor-1 (IGF-1), which is associated with postnatal growth restriction and poor neurologic outcomes. It remains unknown whether supplemental IGF-1 may stimulate neurodevelopment in preterm neonates. Using cesarean-delivered preterm pigs as a model of preterm infants, we investigated the effects of supplemental IGF-1 on motor function and on regional and cellular brain development. Pigs were treated with 2.25 mg/kg/d recombinant human IGF-1/IGF binding protein-3 complex from birth until day 5 or 9 before the collection of brain samples for quantitative immunohistochemistry (IHC), RNA sequencing, and quantitative PCR analyses. Brain protein synthesis was …

Med25 Limits Master Regulators That Govern Adipogenesis, Jasmine Saunders, Kunal Sikder, Elizabeth Phillips, Anurag Ishwar, David Mothy, Kenneth B. Margulies, Jason C. Choi

Department of Medicine Faculty Papers

Mediator 25 (Med25) is a member of the mediator complex that relays signals from transcription factors to the RNA polymerase II machinery. Multiple transcription factors, particularly those involved in lipid metabolism, utilize the mediator complex, but how Med25 is involved in this context is unclear. We previously identified Med25 in a translatome screen of adult cardiomyocytes (CMs) in a novel cell type-specific model of LMNA cardiomyopathy. In this study, we show that Med25 upregulation is coincident with myocardial lipid accumulation. To ascertain the role of Med25 in lipid accumulation, we utilized iPSC-derived and neonatal CMs to recapitulate the in vivo …

Macrophages Promote Repair Of Inner Hair Cell Ribbon Synapses Following Noise-Induced Cochlear Synaptopathy, Vijayprakash Manickam, Dinesh Y Gawande, Andrew R Stothert, Anna C Clayman, Lyudmila Batalkina, Mark E Warchol, Kevin K Ohlemiller, Tejbeer Kaur

2020-Current year OA Pubs

Resident cochlear macrophages rapidly migrate into the inner hair cell synaptic region and directly contact the damaged synaptic connections after noise-induced synaptopathy. Eventually, such damaged synapses are spontaneously repaired, but the precise role of macrophages in synaptic degeneration and repair remains unknown. To address this, cochlear macrophages were eliminated using colony stimulating factor 1 receptor (CSF1R) inhibitor, PLX5622. Sustained treatment with PLX5622 in

Glut1 Is Redundant In Hypoxic And Glycolytic Nucleus Pulposus Cells Of The Intervertebral Disc, Shira N. Johnston, Elizabeth S. Silagi, Vedavathi Madhu, Duc H. Nguyen, Irving M. Shapiro, Makarand V. Risbud

Department of Orthopaedic Surgery Faculty Papers

Glycolysis is central to homeostasis of nucleus pulposus (NP) cells in the avascular intervertebral disc. Since the glucose transporter, GLUT1, is a highly enriched phenotypic marker of NP cells, we hypothesized that it is vital for the development and postnatal maintenance of the disc. Surprisingly, primary NP cells treated with 2 well-characterized GLUT1 inhibitors maintained normal rates of glycolysis and ATP production, indicating intrinsic compensatory mechanisms. We showed in vitro that NP cells mitigated GLUT1 loss by rewiring glucose import through GLUT3. Of note, we demonstrated that substrates, such as glutamine and palmitate, did not compensate for glucose restriction resulting …

In Vivo Functional Characterization Of Egfr Variants Identifies Novel Drivers Of Glioblastoma, Kwanha Yu, Kathleen Kong, Brittney Lozzi, Estefania Luna-Figueroa, Alexis Cervantes, Rachel Curry, Carrie A Mohila, Ganesh Rao, Ali Jalali, Gordon B Mills, Kenneth L Scott, Benjamin Deneen

Faculty, Staff and Students Publications

BACKGROUND: Glioblastoma is the most common and aggressive primary brain tumor. Large-scale sequencing initiatives have cataloged its mutational landscape in hopes of elucidating mechanisms driving this deadly disease. However, a major bottleneck in harnessing this data for new therapies is deciphering "driver" and "passenger" events amongst the vast volume of information.

METHODS: We utilized an autochthonous, in vivo screening approach to identify driver, EGFR variants. RNA-Seq identified unique molecular signatures of mouse gliomas across these variants, which only differ by a single amino acid change. In particular, we identified alterations to lipid metabolism, which we further validated through an unbiased …

A Pilot Study Of The Association Between Maternal Mid-Pregnancy Cholesterol And Oxysterol Concentrations And Labor Duration., Todd C. Rideout, Jaclyn Wallace, Xiaozhong Wen, Vanessa M. Barnabei, Kai Ling Kong, Richard W. Browne

Manuscripts, Articles, Book Chapters and Other Papers

BACKGROUND: Previous animal model studies have highlighted a role for cholesterol and its oxidized derivatives (oxysterols) in uterine contractile activity, however, a lipotoxic state associated with hypercholesterolemia may contribute to labor dystocia. Therefore, we investigated if maternal mid-pregnancy cholesterol and oxysterol concentrations were associated with labor duration in a human pregnancy cohort.

METHODS: We conducted a secondary analysis of serum samples and birth outcome data from healthy pregnant women (N = 25) with mid-pregnancy fasting serum samples collected at 22-28 weeks of gestation. Serum was analyzed for total-C, HDL-C, and LDL-C by direct automated enzymatic assay and oxysterol profile including …

A Comprehensive And Integrative Approach To Mecp2 Disease Transcriptomics, Alexander J Trostle, Lucian Li, Seon-Young Kim, Jiasheng Wang, Rami Al-Ouran, Hari Krishna Yalamanchili, Zhandong Liu, Ying-Wooi Wan

Faculty, Staff and Students Publications

Mutations in MeCP2 result in a crippling neurological disease, but we lack a lucid picture of MeCP2's molecular role. Individual transcriptomic studies yield inconsistent differentially expressed genes. To overcome these issues, we demonstrate a methodology to analyze all modern public data. We obtained relevant raw public transcriptomic data from GEO and ENA, then homogeneously processed it (QC, alignment to reference, differential expression analysis). We present a web portal to interactively access the mouse data, and we discovered a commonly perturbed core set of genes that transcends the limitations of any individual study. We then found functionally distinct, consistently up- and …

High Sucrose Consumption Decouples Intrinsic And Synaptic Excitability Of Agrp Neurons Without Altering Body Weight., Austin C Korgan, Klausen Oliveira-Abreu, Wei Wei, Sophie L A Martin, Zoey J D Bridges, José Henrique Leal-Cardoso, Catherine Kaczorowski, Kristen M S O'Connell

Faculty Research 2023

BACKGROUND/OBJECTIVE: As the obesity epidemic continues, the understanding of macronutrient influence on central nervous system function is critical for understanding diet-induced obesity and potential therapeutics, particularly in light of the increased sugar content in processed foods. Previous research showed mixed effects of sucrose feeding on body weight gain but has yet to reveal insight into the impact of sucrose on hypothalamic functioning. Here, we explore the impact of liquid sucrose feeding for 12 weeks on body weight, body composition, caloric intake, and hypothalamic AgRP neuronal function and synaptic plasticity.

METHODS: Patch-clamp electrophysiology of hypothalamic AgRP neurons, metabolic phenotyping and food …

Macrophage-Derived Mlkl In Alcohol-Associated Liver Disease: Regulation Of Phagocytosis, Xiaoqin Wu, Xiude Fan, Megan R Mcmullen, Tatsunori Miyata, Adam Kim, Vai Pathak, Jianguo Wu, Le Z Day, Josiah E Hardesty, Nicole Welch, Jaividhya Dasarathy, Daniela S Allende, Arthur J Mccullough, Jon M Jacobs, Daniel M Rotroff, Srinivasan Dasarathy, Laura E Nagy

Faculty, Staff and Student Publications

BACKGROUND AND AIMS: Mixed lineage kinase domain-like pseudokinase (MLKL), a key terminal effector of necroptosis, also plays a role in intracellular vesicle trafficking that is critical for regulating liver inflammation and injury in alcohol-associated liver disease (ALD). Although receptor interacting protein kinase 3 (Rip3)-/- mice are completely protected from ethanol-induced liver injury, Mlkl-/- mice are only partially protected. Therefore, we hypothesized that cell-specific functions of MLKL may contribute to ethanol-induced injury.

APPROACH AND RESULTS: Bone marrow transplants between Mlkl-/- mice and littermates were conducted to distinguish the role of myeloid versus nonmyeloid Mlkl in the Gao-binge model of ALD. Ethanol-induced …

Endotrophin Neutralization Through Targeted Antibody Treatment Protects From Renal Fibrosis In A Podocyte Ablation Model, Yu A An, Wei Xiong, Shiuhwei Chen, Dawei Bu, Joseph M Rutkowski, Joel P Berger, Christine M Kusminski, Ningyan Zhang, Zhiqiang An, Philipp E Scherer

Faculty, Staff and Student Publications

OBJECTIVE: Renal fibrosis is a hallmark for chronic kidney disease (CKD), and often leads to end stage renal disease (ESRD). However, limited interventions are available clinically to ameliorate or reverse renal fibrosis.

METHODS: Herein, we evaluated whether blockade of endotrophin through neutralizing antibodies protects from renal fibrosis in the podocyte insult model (the "POD-ATTAC" mouse). We determined the therapeutic effects of endotrophin targeted antibody through assessing renal function, renal inflammation and fibrosis at histological and transcriptional levels, and podocyte regeneration.

RESULTS: We demonstrated that neutralizing endotrophin antibody treatment significantly ameliorates renal fibrosis at the transcriptional, morphological, and functional levels. In …

Dysregulated Amino Acid Sensing Drives Colorectal Cancer Growth And Metabolic Reprogramming Leading To Chemoresistance, Sumeet Solanki, Katherine Sanchez, Varun Ponnusamy, Vasudha Kota, Hannah N Bell, Chun-Seok Cho, Allison H Kowalsky, Michael Green, Jun Hee Lee, Yatrik M Shah

Faculty, Staff and Student Publications

BACKGROUND & AIMS: Colorectal cancer (CRC) is a devastating disease that is highly modulated by dietary nutrients. Mechanistic target of rapamycin complex 1 (mTORC1) contributes to tumor growth and limits therapy responses. Growth factor signaling is a major mechanism of mTORC1 activation. However, compensatory pathways exist to sustain mTORC1 activity after therapies that target oncogenic growth factor signaling. Amino acids potently activate mTORC1 via amino acid-sensing GTPase activity towards Rags (GATOR). The role of amino acid-sensing pathways in CRC is unclear.

METHODS: Human colon cancer cell lines, preclinical intestinal epithelial-specific GATOR1 and GATOR2 knockout mice subjected to colitis-induced or sporadic …

Effect Of Sirolimus On Insulin Dynamics In Horses, Demia J De Tonnerre, Carlos E Medina Torres, Darko Stefanovski, Mary A Robinson, Kate L Kemp, François-René Bertin, Andrew W Van Eps

Faculty, Staff and Student Publications

BACKGROUND: Sirolimus, a mechanistic target of rapamycin inhibitor, suppresses insulin production in other species and has therapeutic potential for hyperinsulinemia in horses.

HYPOTHESIS/OBJECTIVE: Determine the pharmacokinetics (PKs) of sirolimus and evaluate its effect on insulin dynamics in healthy and insulin dysregulation (ID) horses.

ANIMALS: Eight Standardbred geldings.

METHODS: A PK study was performed followed by a placebo-controlled, randomized, crossover study. Blood sirolimus concentrations were measured by liquid chromatography-mass-spectrometry. PK indices were estimated by fitting a 2-compartment model using nonlinear least squares regression. An oral glucose test (OGT) was conducted before and 4, 24, 72, and 144 hours after administration of …

Linoleic Acid Improves Piezo2 Dysfunction In A Mouse Model Of Angelman Syndrome, Luis O Romero, Rebeca Caires, A Kaitlyn Victor, Juanma Ramirez, Francisco J Sierra-Valdez, Patrick Walsh, Vincent Truong, Jungsoo Lee, Ugo Mayor, Lawrence T Reiter, Valeria Vásquez, Julio F Cordero-Morales

Faculty, Staff and Student Publications

Angelman syndrome (AS) is a neurogenetic disorder characterized by intellectual disability and atypical behaviors. AS results from loss of expression of the E3 ubiquitin-protein ligase UBE3A from the maternal allele in neurons. Individuals with AS display impaired coordination, poor balance, and gait ataxia. PIEZO2 is a mechanosensitive ion channel essential for coordination and balance. Here, we report that PIEZO2 activity is reduced in Ube3a deficient male and female mouse sensory neurons, a human Merkel cell carcinoma cell line and female human iPSC-derived sensory neurons with UBE3A knock-down, and de-identified stem cell-derived neurons from individuals with AS. We find that loss …

The Microbiome And Its Impact On Allogeneic Hematopoietic Cell Transplantation, Florent Malard, Robert R Jenq

Faculty, Staff and Student Publications

Allogeneic hematopoietic cell transplantation (alloHCT) is a standard curative therapy for a variety of benign and malignant hematological diseases. Previously, patients who underwent alloHCT were at high risk for complications with potentially life-threatening toxicities, including a variety of opportunistic infections as well as acute and chronic manifestations of graft-versus-host disease (GVHD), where the transplanted immune system can produce inflammatory damage to the patient. With recent advances, including newer conditioning regimens, advances in viral and fungal infection prophylaxis, and novel GVHD prophylactic and treatment strategies, improvements in clinical outcomes have steadily improved. One modality with great potential that has yet to …

Fibroblast Growth Factor 19 Secretion And Function In Perinatal Development, Caitlin Vonderohe, Gregory Guthrie, Douglas G Burrin

Faculty, Staff and Students Publications

Limited work has focused on fibroblast growth factor-19 (FGF19) secretion and function in the perinatal period. FGF19 is a potent growth factor that coordinates development of the brain, eye, inner ear, and skeletal system in the embryo, but after birth, FGF19 transitions to be an endocrine regulator of the classic pathway of hepatic bile acid synthesis. FGF19 has emerged as a mediator of metabolism and bile acid synthesis in aged animals and adults in the context of liver disease and metabolic dysfunction. FGF19 has also been shown to have systemic insulin-sensitizing and skeletal muscle hypertrophic effects when induced or supplemented …

Frequent First-Trimester Pregnancy Loss In Rhesus Macaques Infected With African-Lineage Zika Virus, Jenna R. Rosinski, Kevin K. Noguchi, Et Al.

2020-Current year OA Pubs

In the 2016 Zika virus (ZIKV) pandemic, a previously unrecognized risk of birth defects surfaced in babies whose mothers were infected with Asian-lineage ZIKV during pregnancy. Less is known about the impacts of gestational African-lineage ZIKV infections. Given high human immunodeficiency virus (HIV) burdens in regions where African-lineage ZIKV circulates, we evaluated whether pregnant rhesus macaques infected with simian immunodeficiency virus (SIV) have a higher risk of African-lineage ZIKV-associated birth defects. Remarkably, in both SIV+ and SIV- animals, ZIKV infection early in the first trimester caused a high incidence (78%) of spontaneous pregnancy loss within 20 days. These findings suggest …

Mitochondrial Phosphatidylethanolamine Modulates Ucp1 To Promote Brown Adipose Thermogenesis, Jordan M Johnson, Irfan J Lodhi, Et Al.

2020-Current year OA Pubs

Thermogenesis by uncoupling protein 1 (UCP1) is one of the primary mechanisms by which brown adipose tissue (BAT) increases energy expenditure. UCP1 resides in the inner mitochondrial membrane (IMM), where it dissipates membrane potential independent of adenosine triphosphate (ATP) synthase. Here, we provide evidence that phosphatidylethanolamine (PE) modulates UCP1-dependent proton conductance across the IMM to modulate thermogenesis. Mitochondrial lipidomic analyses revealed PE as a signature molecule whose abundance bidirectionally responds to changes in thermogenic burden. Reduction in mitochondrial PE by deletion of phosphatidylserine decarboxylase (PSD) made mice cold intolerant and insensitive to β3 adrenergic receptor agonist-induced increase in whole-body oxygen …

Tfeb-Mediated Lysosomal Exocytosis Alleviates High-Fat Diet-Induced Lipotoxicity In The Kidney, Jun Nakamura, Takeshi Yamamoto, Yoshitsugu Takabatake, Tomoko Namba-Hamano, Satoshi Minami, Atsushi Takahashi, Jun Matsuda, Shinsuke Sakai, Hiroaki Yonishi, Shihomi Maeda, Sho Matsui, Isao Matsui, Takayuki Hamano, Masatomo Takahashi, Maiko Goto, Yoshihiro Izumi, Takeshi Bamba, Miwa Sasai, Masahiro Yamamoto, Taiji Matsusaka, Fumio Niimura, Motoko Yanagita, Shuhei Nakamura, Tamotsu Yoshimori, Andrea Ballabio, Yoshitaka Isaka

Duncan NRI Faculty and Staff Publications

Obesity is a major risk factor for end-stage kidney disease. We previously found that lysosomal dysfunction and impaired autophagic flux contribute to lipotoxicity in obesity-related kidney disease, in both humans and experimental animal models. However, the regulatory factors involved in countering renal lipotoxicity are largely unknown. Here, we found that palmitic acid strongly promoted dephosphorylation and nuclear translocation of transcription factor EB (TFEB) by inhibiting the mechanistic target of rapamycin kinase complex 1 pathway in a Rag GTPase-dependent manner, though these effects gradually diminished after extended treatment. We then investigated the role of TFEB in the pathogenesis of obesity-related kidney …