Digestive System Diseases Commons^™

Probiotics And Human Milk Differentially Influence The Gut Microbiome And Nec Incidence In Preterm Pigs, Valeria Melendez Hebib, Diana H Taft, Barbara Stoll, Jinxin Liu, Lee Call, Gregory Guthrie, Nick Jensen, Amy B Hair, David A Mills, Douglas G Burrin

Faculty, Staff and Students Publications

Necrotizing enterocolitis (NEC) is the leading cause of death caused by gastrointestinal disease in preterm infants. Major risk factors include prematurity, formula feeding, and gut microbial colonization. Microbes have been linked to NEC, yet there is no evidence of causal species, and select probiotics have been shown to reduce NEC incidence in infants. In this study, we evaluated the effect of the probiotic Bifidobacterium longum subsp. infantis (BL. infantis), alone and in combination with a human milk oligosaccharide (HMO)—sialylactose (3′SL)—on the microbiome, and the incidence of NEC in preterm piglets fed an infant formula diet. We studied 50 …

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 …

Multifaceted Role For P53 In Pancreatic Cancer Suppression, Stephano S Mello, Brittany M Flowers, Pawel K Mazur, James J Lee, Fabian Müller, Sarah K Denny, Sofia Ferreira, Kathryn Hanson, Seung K Kim, William J Greenleaf, Laura D Wood, Laura D Attardi

Faculty, Staff and Student Publications

The vast majority of human pancreatic ductal adenocarcinomas (PDACs) harbor TP53 mutations, underscoring p53's critical role in PDAC suppression. PDAC can arise when pancreatic acinar cells undergo acinar-to-ductal metaplasia (ADM), giving rise to premalignant pancreatic intraepithelial neoplasias (PanINs), which finally progress to PDAC. The occurrence of TP53 mutations in late-stage PanINs has led to the idea that p53 acts to suppress malignant transformation of PanINs to PDAC. However, the cellular basis for p53 action during PDAC development has not been explored in detail. Here, we leverage a hyperactive p53 variant-p5353,54-which we previously showed is a more robust PDAC suppressor than …

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 …

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 …

Hepatocytes Demarcated By Ephb2 Contribute To The Progression Of Nonalcoholic Steatohepatitis, Yang Xiao, Kirill Batmanov, Wenxiang Hu, Kun Zhu, Alexander Y Tom, Dongyin Guan, Chunjie Jiang, Lan Cheng, Sam J Mccright, Eric C Yang, Matthew R Lanza, Yifan Liu, David A Hill, Mitchell A Lazar

Faculty, Staff and Students Publications

Current therapeutic strategies for treating nonalcoholic steatohepatitis (NASH) have failed to alleviate liver fibrosis, which is a devastating feature leading to hepatic dysfunction. Here, we integrated single-nucleus transcriptomics and epigenomics to characterize all major liver cell types during NASH development in mice and humans. The bifurcation of hepatocyte trajectory with NASH progression was conserved between mice and humans. At the nonalcoholic fatty liver (NAFL) stage, hepatocytes exhibited metabolic adaptation, whereas at the NASH stage, a subset of hepatocytes was enriched for the signatures of cell adhesion and migration, which were mainly demarcated by receptor tyrosine kinase ephrin type B receptor …

Regulation Of Skeletal Muscle Protein Synthesis In The Preterm Pig By Intermittent Leucine Pulses During Continuous Parenteral Feeding, Marko Rudar, Agus Suryawan, Hanh V Nguyen, Shaji K Chacko, Caitlin Vonderohe, Barbara Stoll, Douglas G Burrin, Marta L Fiorotto, Teresa A Davis

Faculty, Staff and Students Publications

BACKGROUND: Extrauterine growth restriction is a common complication of preterm birth. Leucine (Leu) is an agonist for the mechanistic target of rapamycin (mTOR) complex 1 (mTORC1) signaling pathway that regulates translation initiation and protein synthesis in skeletal muscle. Previously, we showed that intermittent intravenous pulses of Leu to neonatal pigs born at term receiving continuous enteral nutrition increases muscle protein synthesis and lean mass accretion. Our objective was to determine the impact of intermittent intravenous pulses of Leu on muscle protein anabolism in preterm neonatal pigs administered continuous parenteral nutrition.

METHODS: Following preterm delivery (on day 105 of 115 gestation), …

Eosinophils Protect Against Acetaminophen-Induced Liver Injury Through Cyclooxygenase-Mediated Il-4/Il-13 Production, Long Xu, Yang Yang, Jiali Jiang, Yankai Wen, Jong-Min Jeong, Christoph Emontzpohl, Constance L Atkins, Kangho Kim, Elizabeth A Jacobsen, Hua Wang, Cynthia Ju

Faculty, Staff and Student Publications

BACKGROUND AND AIMS: A better understanding of the underlying mechanism of acetaminophen (APAP)-induced liver injury (AILI) remains an important endeavor to develop therapeutic approaches. Eosinophils have been detected in liver biopsies of patients with APAP overdose. We recently demonstrated a profound protective role of eosinophils against AILI; however, the molecular mechanism had not been elucidated.

APPROACH AND RESULTS: In agreement with our previous data from experiments using genetic deletion of eosinophils, we found that depletion of eosinophils in wild-type (WT) mice by an anti-IL-15 antibody resulted in exacerbated AILI. Moreover, adoptive transfer of eosinophils significantly reduced liver injury and mortality …

Supplementing Glycine And N-Acetylcysteine (Glynac) In Older Adults Improves Glutathione Deficiency, Oxidative Stress, Mitochondrial Dysfunction, Inflammation, Physical Function, And Aging Hallmarks: A Randomized Clinical Trial, Premranjan Kumar, Chun Liu, James Suliburk, Jean W Hsu, Raja Muthupillai, Farook Jahoor, Charles G Minard, George E Taffet, Rajagopal V Sekhar

Faculty, Staff and Students Publications

BACKGROUND: Elevated oxidative stress (OxS), mitochondrial dysfunction, and hallmarks of aging are identified as key contributors to aging, but improving/reversing these defects in older adults (OA) is challenging. In prior studies, we identified that deficiency of the intracellular antioxidant glutathione (GSH) could play a role and reported that supplementing GlyNAC (combination of glycine and N-acetylcysteine [NAC]) in aged mice improved GSH deficiency, OxS, mitochondrial fatty-acid oxidation (MFO), and insulin resistance (IR). To test whether GlyNAC supplementation in OA could improve GSH deficiency, OxS, mitochondrial dysfunction, IR, physical function, and aging hallmarks, we conducted a placebo-controlled randomized clinical trial.

METHODS: Twenty-four …

Adar1 Deletion Causes Degeneration Of The Exocrine Pancreas Via Mavs-Dependent Interferon Signaling, Dhwani N Rupani, Fredrik I Thege, Vidhi Chandra, Hajar Rajaei, Robert W Cowan, Sonja M Wörmann, Olivereen Le Roux, Prerna Malaney, Sara L Manning, Jack Hashem, Jennifer Bailey-Lundberg, Andrew D Rhim, Florencia Mcallister

Faculty, Staff and Student Publications

Adenosine deaminase acting on RNA 1 (ADAR1) is an RNA-binding protein that deaminates adenosine (A) to inosine (I). A-to-I editing alters post-transcriptional RNA processing, making ADAR1 a crucial regulator of gene expression. Consequently, Adar1 has been implicated in organogenesis. To determine the role of Adar1 in pancreatic development and homeostasis, we conditionally deleted Adar1 from the murine pancreas (Ptf1aCre/+; Adar1Fl/Fl). The resulting mice had stunted growth, likely due to malabsorption associated with exocrine pancreatic insufficiency. Analyses of pancreata revealed ductal cell expansion, heightened interferon-stimulated gene expression and an increased influx of immune cells. Concurrent deletion of Adar1 and Mavs, a …

Pyrolyzed Deketene Curcumin Controls Regulatory T Cell Generation And Gastric Cancer Metabolism Cooperate With 2-Deoxy-D-Glucose, Takashi Maruyama, Hirofumi Miyazaki, Yun-Ji Lim, Jian Gu, Masaki Ishikawa, Taichi Yoshida, Wanjun Chen, Yuji Owada, Hiroyuki Shibata

Faculty, Staff and Student Publications

Pyrolyzed deketene curcumin GO-Y022 prevents carcinogenesis in a gastric cancer mouse model. However, it is still less clear if GO-Y022 affects tumor-induced immune suppression. In this study, we found that GO-Y022 inhibited Treg generation in the presence of transforming growth factor beta 1 (TGF-β). However, GO-Y022 showed less impact on Foxp3+ Tregs in the gastric tumor microenvironment. Gastric tumor cells produce a large amount of L-lactate in the presence of GO-Y022 and diminish the inhibitory role of GO-Y022 against Treg generation in response to TGF-β. Therefore, naïve CD4+ T cells co-cultured with GO-Y022 treated gastric tumor cells increased Treg generation. …

Sox9 Governs Gastric Mucous Neck Cell Identity And Is Required For Injury-Induced Metaplasia, Spencer G Willet, Nattapon Thanintorn, Helen Mcneill, Sung-Ho Huh, David M Ornitz, Won Jae Huh, Stella G Hoft, Richard J Dipaolo, Jason C Mills

Faculty, Staff and Students Publications

BACKGROUND & AIMS: Acute and chronic gastric injury induces alterations in differentiation within the corpus of the stomach called pyloric metaplasia. Pyloric metaplasia is characterized by the death of parietal cells and reprogramming of mitotically quiescent zymogenic chief cells into proliferative, mucin-rich spasmolytic polypeptide-expressing metaplasia (SPEM) cells. Overall, pyloric metaplastic units show increased proliferation and specific expansion of mucous lineages, both by proliferation of normal mucous neck cells and recruitment of SPEM cells. Here, we identify Sox9 as a potential gene of interest in the regulation of mucous neck and SPEM cell identity in the stomach.

METHODS: We used immunostaining …

Combining Mek And Src Inhibitors For Treatment Of Colorectal Cancer Demonstrate Increased Efficacy In Vitro But Not In Vivo, Fan Fan, Susmita Ghosh, Reid Powell, Jason Roszik, Yongsun Park, Mary Sobieski, Alexey Sorokin, Clifford Stephan, Scott Kopetz, Lee M Ellis, Rajat Bhattacharya

Faculty, Staff and Student Publications

Metastatic colorectal cancer (mCRC) is the second leading cause of cancer deaths in the United States. More than 50% of patients with mCRC harbor mutations of the oncogenic driver RAS (KRAS or NRAS). Because directly targeting most mutations of RAS is technically challenging, researchers have concentrated on targeting MEK, a downstream mediator of RAS. However, targeting MEK as single-agent therapy is ineffective in patients with mCRC. We hypothesize that combining a MEK inhibitor with other agents can enhance the efficacy of MEK targeting in mCRC. Unbiased high-throughput screening (HTS) was performed to identify drugs that enhance the efficacy of MEK …

In Vitro And In Vivo Phototoxicity On Gastric Mucosa Induced By Methylene Blue, Hui Yeong Oh, Hyun Ho Choi, Eui Jin Kim, Ji Hye Choi, Sung Sook Choi, Hae Kyung Lee, Hyung-Keun Kim, Sang Woo Kim, Won Sang H Park, Hiun Suk Chae

Faculty, Staff and Student Publications

BACKGROUND: Methylene blue (MB) is used endoscopically to demarcate tumors and as a photosensitizer in photodynamic therapy (PDT). However, there are few in vivo studies about its toxicity in healthy stomach tissue. We performed sequential in vitro and in vivo analyses of MB-induced phototoxicity.

METHODS: We performed in vitro experiments using the AGS human gastric cancer cell line treated with light-emitting diode (LED) irradiation (3.6 J/cm

RESULTS: In vitro, increased concentrations of MB led to higher TUNEL scores. However, cell viability was significantly lower after MB plus LED irradiation than after treatment with MB alone (P < 0.001). In vivo, the TUNEL score was highest immediately after treatment with 0.1% or 0.5% MB plus light irradiation, and the score was significantly higher in the LED illumination plus MB group than in the control group (P < 0.05). The elevated TUNEL score was maintained for 3 days in the MB plus light irradiation group but returned to normal levels on day 10.

CONCLUSIONS: : Endoscopic light …

Evaluation Of Murine Host Sex As A Biological Variable In Transplanted Human Intestinal Organoid Development, Eoin P Mcneill, Vikas S Gupta, David J Sequeira, Noah F Shroyer, Allison L Speer

Faculty, Staff and Student Publications

Background: Human intestinal organoids (HIOs), when transplanted into immunocompromised mice (tHIOs), demonstrate significant growth and maturation. While both male and female mice are reported to be viable hosts for these experiments, a direct comparison of sex-related differences in tHIO structure and development has not been performed.

Aims: We sought to identify host sex-related differences in tHIO engraftment, morphology, and epithelial and mesenchymal development.

Methods: HIOs were generated in vitro and transplanted beneath the kidney capsule of NSG male and female mice. tHIOs were harvested at 8-9 weeks. Anthropometric measurements were captured. tHIOs were divided in half and histology or RT-qPCR …

Coating Formulation Change Leads To Inferior Performance Of Long-Lasting Insecticidal Nets In Papua New Guinea, Nakei Bubun, Evodia Anetul, Melanie Koinari, Timothy W Freeman, Stephan Karl

Faculty, Staff and Student Publications

BACKGROUND: Long-lasting insecticidal nets (LLINs) play a key role in reducing malaria transmission in endemic countries. In a previous study, the authors demonstrated a substantial decrease in the bioefficacy of LLINs for malaria prevention delivered to Papua New Guinea (PNG) between 2013 and 2019. This coincided with a rise in malaria cases in the country. The present study was aimed at determining the underlying cause of the reduced bioefficacy observed in these LLINs. The main hypothesis was that a change in the coating formulation of the respective LLIN product was responsible, and had led to significantly altered product properties and …

Nab-Paclitaxel, Capecitabine, And Radiation Therapy After Induction Chemotherapy In Treating Patients With Locally Advanced And Borderline Resectable Pancreatic Cancer: Phase 1 Trial And Imaging-Based Biomarker Validation, Eugene J Koay, Mohamed Zaid, Maureen Aliru, Polycarpe Bagereka, Arie Van Wieren, Maria Jovie Rodriguez, Galia Jacobson, Robert A Wolff, Michael Overman, Gauri Varadhachary, Shubham Pant, Huamin Wang, Ching-Wei Tzeng, Naruhiko Ikoma, Michael Kim, Jeffrey E Lee, Matthew Hg Katz, Eric Tamm, Priya Bhosale, Cullen M Taniguchi, Emma B Holliday, Grace L Smith, Ethan B Ludmir, Bruce D Minsky, Christopher H Crane, Albert C Koong, Prajnan Das, Xuemei Wang, Milind Javle, Sunil Krishnan

Faculty, Staff and Student Publications

PURPOSE: Effective consolidative chemoradiation (CRT) regimens are lacking. In this phase 1 trial, we evaluated the safety and efficacy of nab-paclitaxel, capecitabine, and radiation therapy after induction chemotherapy in patients with locally advanced and borderline-resectable pancreatic cancer (LAPC and BRPC). Also, we evaluated a computed tomography (CT)-based biomarker of response.

METHODS AND MATERIALS: Eligible patients had pathologically confirmed pancreatic ductal adenocarcinoma, underwent computed tomography-imaging, received a diagnosis of LAPC or BRPC, and received induction chemotherapy. Standard 3 + 3 study design was used, with 3 escalating nab-paclitaxel dose levels (50, 75, and 100 mg/m

RESULTS: Twenty-three patients started and finished …

Infant Behavioral State And Stool Microbiome In Infants Receiving Lactocaseibacillus Rhamnosus Gg In Formula: Randomized Controlled Trial, Robert J Shulman, Maciej Chichlowski, Fabiola Gutierrez Orozco, Cheryl L Harris, Jennifer L Wampler, Nicholas A Bokulich, Carol Lynn Berseth

Faculty, Staff and Students Publications

BACKGROUND: Our aim was to evaluate infant behavioral state, stool microbiome profile and calprotectin in infants with infantile colic receiving a partially hydrolyzed protein formula with or without added Lacticaseibacillus (formerly Lactobacillus) rhamnosus GG (LGG).

METHODS: In this single-center, double-blind, controlled, parallel, prospective study, term infants (14-28 days of age) identified with colic (using modified Wessel's criteria: cried and/or fussed ≥ 3 h/day for ≥ 3 days/week, in a one-week period) were randomized to receive one of two formulas over a three-week feeding period: marketed partially hydrolyzed cow's milk-based infant formula (PHF, n = 35) or a similar formula with …

Dietary Fat Composition Shapes Bile Acid Metabolism And Severity Of Liver Injury In A Pig Model Of Pediatric Nafld, Rodrigo Manjarín, Kayla Dillard, Morgan Coffin, Gabriella V Hernandez, Victoria A Smith, Trista Noland-Lidell, Tanvi R Gehani, Hayden J Smart, Kevin Wheeler, Kimberly A Sprayberry, Mark S Edwards, Rob K Fanter, Hunter Glanz, Chad Immoos, Tasha M Santiago-Rodriguez, Jason M Blank, Douglas G Burrin, Brian D Piccolo, Mohammed Abo-Ismail, Michael R La Frano, Magdalena Maj

Faculty, Staff and Students Publications

The objective of this study was to investigate the effect of dietary fatty acid (FA) composition on bile acid (BA) metabolism in a pig model of NAFLD, by using a multiomics approach combined with histology and serum biochemistry. Thirty 20-day-old Iberian pigs pair-housed in pens were randomly assigned to receive 1 of 3 hypercaloric diets for 10 wk: 1) lard-enriched (LAR; n = 5 pens), 2) olive oil-enriched (OLI; n = 5), and 3) coconut oil-enriched (COC; n = 5). Animals were euthanized on week 10 after blood sampling, and liver, colon, and distal ileum (DI) were …

A Phospholipid Mimetic Targeting Lrh-1 Ameliorates Colitis, Suzanne G Mays, Emma H D'Agostino, Autumn R Flynn, Xiangsheng Huang, Guohui Wang, Xu Liu, Elizabeth J Millings, C Denise Okafor, Anamika Patel, Michael L Cato, Jeffery L Cornelison, Diana Melchers, René Houtman, David D Moore, John W Calvert, Nathan T Jui, Eric A Ortlund

Faculty, Staff and Students Publications

Phospholipids are ligands for nuclear hormone receptors (NRs) that regulate transcriptional programs relevant to normal physiology and disease. Here, we demonstrate that mimicking phospholipid-NR interactions is a robust strategy to improve agonists of liver receptor homolog-1 (LRH-1), a therapeutic target for colitis. Conventional LRH-1 modulators only partially occupy the binding pocket, leaving vacant a region important for phospholipid binding and allostery. Therefore, we constructed a set of molecules with elements of natural phospholipids appended to a synthetic LRH-1 agonist. We show that the phospholipid-mimicking groups interact with the targeted residues in crystal structures and improve binding affinity, LRH-1 transcriptional activity, …

Cholestasis Alters Brain Lipid And Bile Acid Composition And Compromises Motor Function In Neonatal Piglets, Nicole Lind Henriksen, Svend Høime Hansen, Matthew Domenic Lycas, Xiaoyu Pan, Thomas Eriksen, Lars Søndergaard Johansen, Richard R Sprenger, Christer Stenby Ejsing, Douglas G Burrin, Kerstin Skovgaard, Vibeke Brix Christensen, Thomas Thymann, Stanislava Pankratova

Faculty, Staff and Students Publications

Infants with neonatal cholestasis are prone to neurodevelopmental deficits, however, the underlying pathogenesis is unclear. Lipid malabsorption and accumulation of potentially neurotoxic molecules in the blood such as bile acids are important yet relatively unexplored pathways. Here, we developed a translational piglet model to understand how the molecular bile acid and lipid composition of the brain is affected by this disease and relates to motor function. Piglets (8-days old) had bile duct ligation or sham surgery and were fed a formula diet for 3 weeks. Alongside sensory-motor deficits observed in bile duct-ligated animals, we found a shift toward a more …

Maternal And Fetal Bile Acid Homeostasis Regulated By Sulfated Progesterone Metabolites Through Fxr Signaling Pathway In A Pregnant Sow Model, Peng Wang, Peiqiang Yuan, Sen Lin, Heju Zhong, Xiaoling Zhang, Yong Zhuo, Jian Li, Lianqiang Che, Bin Feng, Yan Lin, Shengyu Xu, De Wu, Douglas G Burrin, Zhengfeng Fang

Faculty, Staff and Students Publications

Abnormally elevated circulating bile acids (BA) during pregnancy endanger fetal survival and offspring health; however, the pathology and underlying mechanisms are poorly understood. A total of nineteen pregnant sows were randomly assigned to day 60 of gestation, day 90 of gestation (G60, G90), and the farrowing day (L0), to investigate the intercorrelation of reproductive hormone, including estradiol, progesterone and sulfated progesterone metabolites (PMSs), and BA in the peripheral blood of mother and fetuses during pregnancy. All data were analyzed by Student’s t-test or one-way ANOVA of GraphPad Prism and further compared by using the Student–Newman–Keuls test. Correlation analysis was …

Evaluation Of Heat Inactivation Of Human Norovirus In Freshwater Clams Using Human Intestinal Enteroids, Tsuyoshi Hayashi, Yoko Yamaoka, Atsushi Ito, Takashi Kamaishi, Ryuichi Sugiyama, Mary K Estes, Masamichi Muramatsu, Kosuke Murakami

Faculty, Staff and Students Publications

Foodborne disease attributed to the consumption of shellfish contaminated with human norovirus (HuNoV) is one of many global health concerns. Our study aimed to determine the conditions of the heat-inactivation of HuNoV in freshwater clams (Corbicula japonica) using a recently developed HuNoV cultivation system employing stem-cell derived human intestinal enteroids (HIEs). We first measured the internal temperature of the clam tissue in a water bath during boiling at 90 °C and found that approximately 2 min are required for the tissue to reach 90 °C. Next, GII.4 HuNoV was spiked into the center of the clam tissue, followed …

Depletion Of Transmembrane Mucin 4 (Muc4) Alters Intestinal Homeostasis In A Genetically Engineered Mouse Model Of Colorectal Cancer, Ramesh Pothuraju, Priya Pai, Sanjib Chaudhary, Jawed A Siddiqui, Jesse L Cox, Sukhwinder Kaur, Satyanarayana Rachagani, Hemant K Roy, Michael Bouvet, Surinder K Batra

Faculty, Staff and Students Publications

Mucins are components of the mucus layer overlying the intestinal epithelial cells, which maintains physiological homeostasis. Altered mucin expression is associated with disease progression. Expression of MUC4 decreases in colorectal cancer (CRC); however, its functional role and implications in the intestinal pathology in CRC are not studied well. Therefore, we generated a genetically engineered Muc4 knockout (Muc4-/-) CRC mouse model by crossing with Muc4-/- and Apc^flox/flox mice in the presence of colon-specific inducible Cre. We observed that deficiency of Muc4 results in an increased number of macroscopic tumors in the colon and rectal region and leads to poor survival. …

Regulation Of The Double-Stranded Rna Response Through Adar1 Licenses Metaplastic Reprogramming In Gastric Epithelium, José B Sáenz, Nancy Vargas, Charles J Cho, Jason C Mills

Faculty, Staff and Students Publications

Cells recognize both foreign and host-derived double-stranded RNA (dsRNA) via a signaling pathway that is usually studied in the context of viral infection. It has become increasingly clear that the sensing and handling of endogenous dsRNA is also critical for cellular differentiation and development. The adenosine RNA deaminase, ADAR1, has been implicated as a central regulator of the dsRNA response, but how regulation of the dsRNA response might mediate cell fate during injury and whether such signaling is cell intrinsic remain unclear. Here, we show that the ADAR1-mediated response to dsRNA was dramatically induced in 2 distinct injury models of …

Mapk4 Promotes Triple Negative Breast Cancer Growth And Reduces Tumor Sensitivity To Pi3k Blockade, Wei Wang, Dong Han, Qinbo Cai, Tao Shen, Bingning Dong, Michael T Lewis, Runsheng Wang, Yanling Meng, Wolong Zhou, Ping Yi, Chad J Creighton, David D Moore, Feng Yang

Faculty, Staff and Students Publications

About 15-20% of breast cancer (BCa) is triple-negative BCa (TNBC), a devastating disease with limited therapeutic options. Aberrations in the PI3K/PTEN signaling pathway are common in TNBC. However, the therapeutic impact of PI3K inhibitors in TNBC has been limited and the mechanism(s) underlying this lack of efficacy remain elusive. Here, we demonstrate that a large subset of TNBC expresses significant levels of MAPK4, and this expression is critical for driving AKT activation independent of PI3K and promoting TNBC cell and xenograft growth. The ability of MAPK4 to bypass PI3K for AKT activation potentially provides a direct mechanism regulating tumor sensitivity …

Pathologic Inflammation In Malnutrition Is Driven By Proinflammatory Intestinal Microbiota, Large Intestine Barrier Dysfunction, And Translocation Of Bacterial Lipopolysaccharide, Grace T Patterson, Elvia Y Osorio, Alex Peniche, Sara M Dann, Erika Cordova, Geoffrey A Preidis, Ji Ho Suh, Ichiaki Ito, Omar A Saldarriaga, Michael Loeffelholz, Nadim J Ajami, Bruno L Travi, Peter C Melby

Faculty, Staff and Students Publications

Acute malnutrition, or wasting, is implicated in over half of all deaths in children under five and increases risk of infectious disease. Studies in humans and preclinical models have demonstrated that malnutrition is linked to an immature intestinal microbiota characterized by increased prevalence of Enterobacteriaceae. Observational studies in children with moderate acute malnutrition (MAM) have also observed heightened systemic inflammation and increased circulating bacterial lipopolysaccharides (LPS; endotoxin). However, the mechanisms that underpin the systemic inflammatory state and endotoxemia, and their pathophysiological consequences, remain uncertain. Understanding these pathophysiological mechanisms is necessary to design targeted treatments that will improve the unacceptable rate …

The Autophagic Protein P62 Is A Target Of Reactive Aldehydes In Human And Murine Cholestatic Liver Disease, Colin T Shearn, Aimee L Anderson, Michael W Devereux, David J Orlicky, Cole Michel, Dennis R Petersen, Colin G Miller, Sanjiv Harpavat, Edward E Schmidt, Ronald J Sokol

Faculty, Staff and Students Publications

Inflammatory cholestatic liver diseases, including Primary Sclerosing Cholangitis (PSC), are characterized by periportal inflammation with progression to cirrhosis. The objective of this study was to examine interactions between oxidative stress and autophagy in cholestasis. Using hepatic tissue from male acute cholestatic (bile duct ligated) as well as chronic cholestatic (Mdr2KO) mice, localization of oxidative stress, the antioxidant response and induction of autophagy were analyzed and compared to human PSC liver. Concurrently, the ability of reactive aldehydes to post-translationally modify the autophagosome marker p62 was assessed in PSC liver tissue and in cell culture. Expression of autophagy markers was upregulated in …

Adipose Tissue Hyaluronan Production Improves Systemic Glucose Homeostasis And Primes Adipocytes For Cl 316,243-Stimulated Lipolysis, Yi Zhu, Na Li, Mingyang Huang, Mason Bartels, Sophie Dogné, Shangang Zhao, Xi Chen, Clair Crewe, Leon Straub, Lavanya Vishvanath, Zhuzhen Zhang, Mengle Shao, Yongjie Yang, Christy M Gliniak, Ruth Gordillo, Gordon I Smith, William L Holland, Rana K Gupta, Bingning Dong, Nathalie Caron, Yong Xu, Yucel Akgul, Samuel Klein, Philipp E Scherer

Faculty, Staff and Students Publications

Plasma hyaluronan (HA) increases systemically in type 2 diabetes (T2D) and the HA synthesis inhibitor, 4-Methylumbelliferone, has been proposed to treat the disease. However, HA is also implicated in normal physiology. Therefore, we generated a Hyaluronan Synthase 2 transgenic mouse line, driven by a tet-response element promoter to understand the role of HA in systemic metabolism. To our surprise, adipocyte-specific overproduction of HA leads to smaller adipocytes and protects mice from high-fat-high-sucrose-diet-induced obesity and glucose intolerance. Adipocytes also have more free glycerol that can be released upon beta3 adrenergic stimulation. Improvements in glucose tolerance were not linked to increased plasma …

Vertical Sleeve Gastrectomy Confers Metabolic Improvements By Reducing Intestinal Bile Acids And Lipid Absorption In Mice, Lili Ding, Eryun Zhang, Qiaoling Yang, Lihua Jin, Kyle M Sousa, Bingning Dong, Yangmeng Wang, Jui Tu, Xiaoxiao Ma, Jingyan Tian, Hongli Zhang, Zhipeng Fang, Ana Guan, Yixin Zhang, Zhengtao Wang, David D Moore, Li Yang, Wendong Huang

Faculty, Staff and Students Publications

Vertical sleeve gastrectomy (VSG) is a highly effective bariatric surgery that sustainably treats obesity and type 2 diabetes (T2D). However, the underlying mechanisms governing its metabolic benefits remain unclear. In this study, we have used four different genetically modified mouse lines to understand the link between bile acid circulation and metabolic effects of VSG. Instead of directly activating the nuclear bile acid receptor farnesoid X receptor (Fxr) in the liver or intestine, VSG reduces intestinal levels of bile acids, thereby decreasing fat absorption in the intestine. Given the rising popularity of bariatric surgeries to treat obesity and associated T2D, the …