Pharmacology, Toxicology and Environmental Health Commons^™

Ontogeny Related Changes In The Pediatric Liver Metabolome., Christopher M. Wilson, Qian Li, R Gaedigk, Chengpeng Bi, Saskia N. De Wildt, J Steven Leeder, Brooke L. Fridley

Manuscripts, Articles, Book Chapters and Other Papers

Background: A major challenge in implementing personalized medicine in pediatrics is identifying appropriate drug dosages for children. The majority of drug dosing studies have been based on adult populations, often with modification of the dosing for children based on size and weight. However, the growth and development experienced by children between birth and adulthood represents a dynamically changing biological system, with implications for effective drug dosing, efficacy as well as potential drug toxicity. The purpose of this study was to apply a metabolomics approach to gain preliminary insights into the ontogeny of liver function from newborn to adolescent.

Methods: Metabolites …

Acetaminophen Protein Adducts In Hospitalized Children Receiving Multiple Doses Of Acetaminophen., Sibo Jiang, Valvanera Vozmediano, Susan M. Abdel-Rahman, Stephan Schmidt, Laura P. James

Manuscripts, Articles, Book Chapters and Other Papers

Previous reports have questioned the safety of multiple doses of acetaminophen administered to ill children. Acetaminophen protein adducts (adducts) are a biomarker of acetaminophen-induced liver injury and reflect the oxidative metabolism of acetaminophen, a known mechanism in acetaminophen toxicity. In this prospective observational study, we analyzed adduct concentrations in 1034 blood samples obtained from 181 hospitalized children (1 to 18 years inclusive) who received 2 or more doses of acetaminophen. Linear regression analysis showed that serum adduct concentrations increased as a function of the cumulative acetaminophen dose, which could be attributed, in part, to a long half-life of adducts (2.17 …

Environmental Microcystin Targets The Microbiome And Increases The Risk Of Intestinal Inflammatory Pathology Via Nox2 In Underlying Murine Model Of Nonalcoholic Fatty Liver Disease, Sutapa Sarkar, Diana Kimono, Muayad Albadrani, Ratanesh K. Seth, Philip Busbee, Hasan Alghetaa, Dwayne E. Porter, Geoff I. Scott, Bryan Brooks, Mitzi Nagarkatti, Prakash Nagarkatti, Saurabh Chatterjee

Faculty Publications

With increased climate change pressures likely to influence harmful algal blooms, exposure to microcystin, a known hepatotoxin and a byproduct of cyanobacterial blooms can be a risk factor for NAFLD associated comorbidities. Using both in vivo and in vitro experiments we show that microcystin exposure in NAFLD mice cause rapid alteration of gut microbiome, rise in bacterial genus known for mediating gut inflammation and lactate production. Changes in the microbiome were strongly associated with inflammatory pathology in the intestine, gut leaching, tight junction protein alterations and increased oxidative tyrosyl radicals. Increased lactate producing bacteria from the altered microbiome was associated …

Developmental Expression Of The Cytosolic Sulfotransferases In Human Liver., Sarah Dubaisi, Joseph A. Caruso, R Gaedigk, Carrie A. Vyhlidal, Philip C. Smith, Ronald N. Hines, Thomas A. Kocarek, Melissa Runge-Morris

Manuscripts, Articles, Book Chapters and Other Papers

The liver is the predominant organ of metabolism for many endogenous and foreign chemicals. Cytosolic sulfotransferases (SULTs) catalyze the sulfonation of drugs and other xenobiotics, as well as hormones, neurotransmitters, and sterols, with consequences that include enhanced drug elimination, hormone inactivation, and procarcinogen bioactivation. SULTs are classified into six gene families, but only SULT1 and SULT2 enzymes are expressed in human liver. We characterized the developmental expression patterns of SULT1 and SULT2 mRNAs and proteins in human liver samples using reverse transcription quantitative polymerase chain reaction (RT-qPCR), RNA sequencing, and targeted quantitative proteomics. Using a set of prenatal, infant, and …

Proteomics Of Human Liver Membrane Transporters: A Focus On Fetuses And Newborn Infants., Bianca D. Van Groen, Evita Van De Steeg, Miriam G. Mooij, Marola M H Van Lipzig, Barbara A E De Koning, Robert M. Verdijk, Heleen M. Wortelboer, R Gaedigk, Chengpeng Bi, J Steven Leeder, Ron H N Van Schaik, Joost Van Rosmalen, Dick Tibboel, Wouter H. Vaes, Saskia N. De Wildt

Manuscripts, Articles, Book Chapters and Other Papers

BACKGROUND: Hepatic membrane transporters are involved in the transport of many endogenous and exogenous compounds, including drugs. We aimed to study the relation of age with absolute transporter protein expression in a cohort of 62 mainly fetus and newborn samples.

METHODS: Protein expressions of BCRP, BSEP, GLUT1, MCT1, MDR1, MRP1, MRP2, MRP3, NTCP, OCT1, OATP1B1, OATP1B3, OATP2B1 and ATP1A1 were quantified with LC-MS/MS in isolated crude membrane fractions of snap-frozen post-mortem fetal and pediatric, and surgical adult liver samples. mRNA expression was quantified using RNA sequencing, and genetic variants with TaqMan assays. We explored relationships between protein expression and age …

Evaluation Of Perfluorohexane Sulfonate (Pfhxs) Exposure To Risk Of Liver Disease Caused By High Fat Fructose Diet, Dwight C. Anderson

Senior Honors Projects

Perfluorohexane sulfonate (PFHxS) has been used in products as surfactants[AS1] . These products include fluoropolymers and as protective and water-resistant coatings to different materials such as carpets, paper, and textiles. Also, evidence of PFHxS exposure has been reported in firefighters who use certain film forming foams. Current investigations have shown widespread exposure to PFHxS in the environment, specifically in drinking water. There has also been evidence of PFHxS accumulation in humans, with a half-life lasting several years.

PFHxS is one of several perfluoronated alkyl substances (PFAS). Other PFASs are considered to be hepatotoxic in rodents and potentially in humans. Studies …

A Compromised Liver Alters Polychlorinated Biphenyl-Mediated Toxicity, Banrida Wahlang, Jordan T. Perkins, Michael C. Petriello, Jessie B. Hoffman, Arnold J. Stromberg, Bernhard Hennig

Superfund Research Center Faculty Publications

Exposure to environmental toxicants namely polychlorinated biphenyls (PCBs) is correlated with multiple health disorders including liver and cardiovascular diseases. The liver is important for both xenobiotic and endobiotic metabolism. However, the responses of an injured liver to subsequent environmental insults has not been investigated. The current study aims to evaluate the role of a compromised liver in PCB-induced toxicity and define the implications on overall body homeostasis. Male C57Bl/6 mice were fed either an amino acid control diet (CD) or a methionine-choline deficient diet (MCD) during the 12-week study. Mice were subsequently exposed to either PCB126 (4.9 mg/kg) or the …

Distribution, Elimination, And Biopersistence To 90 Days Of A Systemically Introduced 30 Nm Ceria-Engineered Nanomaterial In Rats, Robert A. Yokel, Tu C. Au, Robert Macphail, Sarita S. Hardas, D. Allan Butterfield, Rukhsana Sultana, Michael Goodman, Michael T. Tseng, Mo Dan, Hamed Haghnazar, Jason M. Unrine, Uschi M. Graham, Peng Wu, Eric A. Grulke

Pharmaceutical Sciences Faculty Publications

Nanoceria is used as a catalyst in diesel fuel, as an abrasive in printed circuit manufacture, and is being pursued as an antioxidant therapeutic. Our objective is to extend previous findings showing that there were no reductions of cerium in organs of the mononuclear phagocyte (reticuloendothelial) system up to 30 days after a single nanoscale ceria administration. An ~5% aqueous dispersion of citrate-stabilized 30 nm ceria, synthesized and characterized in-house, or vehicle, was iv infused into rats terminated 1, 7, 30, or 90 days later. Cageside observations were obtained daily, body weight weekly. Daily urinary and fecal cerium outputs were …

Effects Of Long-Term Pioglitazone Treatment On Peripheral And Central Markers Of Aging, Eric M. Blalock, Jeremiah T. Phelps, Tristano Pancani, James L. Searcy, Katie L. Anderson, John C. Gant, Jelena Popovic, Margarita G. Avdiushko, Don A. Cohen, Kuey-Chu Chen, Nada M. Porter, Olivier Thibault

Pharmacology and Nutritional Sciences Faculty Publications

BACKGROUND: Thiazolidinediones (TZDs) activate peroxisome proliferator-activated receptor gamma (PPARgamma) and are used clinically to help restore peripheral insulin sensitivity in Type 2 diabetes (T2DM). Interestingly, long-term treatment of mouse models of Alzheimer's disease (AD) with TZDs also has been shown to reduce several well-established brain biomarkers of AD including inflammation, oxidative stress and Abeta accumulation. While TZD's actions in AD models help to elucidate the mechanisms underlying their potentially beneficial effects in AD patients, little is known about the functional consequences of TZDs in animal models of normal aging. Because aging is a common risk factor for both AD and …

Hepatoprotective Effects Of Artemisia Scoparia Against Carbon Tetrachloride: An Environmental Contaminant, A H. Gilani, K H. Janbaz

Department of Biological & Biomedical Sciences

The hepatoprotective activity of crude extract of artemisia scoparia (aerial parts) was investigated against experimentally produced hepatic damage using carbon tetrachloride (CCl4) as a model hepatotoxin. CCl4 at the dose of 1.5 ml/kg, produced liver damage in rats as manifested by the rise in serum levels of AST and ALT to 395 +/- 110 and 258 +/- 61 IU/l (mean +/- SEM; n = 10) respectively, compared to control values of 106 +/- 15 and 26 +/- 04. Pretreatment of rats with plant extract (150 mg/kg) significantly lowered (P < 0.01), the respective serum GOT and GPT levels to 93 +/- 05 and 27 +/- 03 IU/l, indicating hepatoprotective action. Pentobarbital sodium (75 mg/kg)-induced sleeping time in mice was found to be 140.8 +/- 1.5 min (n = 10) which was similar (P > 0.05) to that obtained in the group of animals pretreated with …

Modification Of Chromium(Vi)-Induced Dna Damage By Glutathione And Cytochromes P-450 In Chicken Embryo Hepatocytes., Doreen Y. Cupo, Karen E. Wetterhahn

Dartmouth Scholarship

The role of glutathione and cytochrome P-450 in the production of DNA damage by chromium(VI) was examined in chicken embryo hepatocytes by the alkaline elution technique. Cellular levels of glutathione and cytochrome P-450 were altered by treating the hepatocytes with N-acetyl-L-cysteine, buthionine sulfoximine, isopentanol, or beta-naphthoflavone. A dramatic increase in chromium(VI)-induced DNA strand breaks was observed after increasing glutathione levels in the cells. Chromium(VI)-induced DNA strand breaks were even more numerous when the level of cytochrome P-450 was also increased. Upon depletion of glutathione levels and induction of cytochrome P-450 or cytochrome P-448, little or no DNA strand breaks or …