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Topić Popović N, Čižmek L, Babić S, Strunjak-Perović I, Čož-Rakovac R. Fish liver damage related to the wastewater treatment plant effluents. Environ Sci Pollut Res Int 2023; 30:48739-48768. [PMID: 36869954 PMCID: PMC9985104 DOI: 10.1007/s11356-023-26187-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 02/24/2023] [Indexed: 04/16/2023]
Abstract
Wastewater treatment plants (WWTPs) continuously release a complex mixture of municipal, hospital, industrial, and runoff chemicals into the aquatic environment. These contaminants are both legacy contaminants and emerging-concern contaminants, affecting all tissues in a fish body, particularly the liver. The fish liver is the principal detoxifying organ and effects of consistent pollutant exposure can be evident on its cellular and tissue level. The objective of this paper is thus to provide an in-depth analysis of the WWTP contaminants' impact on the fish liver structure, physiology, and metabolism. The paper also gives an overview of the fish liver biotransformation enzymes, antioxidant enzymes, and non-enzymatic antioxidants, their role in metabolizing xenobiotic compounds and coping with oxidative damage. Emphasis has been placed on highlighting the vulnerability of fish to xenobiotic compounds, and on biomonitoring of exposed fish, generally involving observation of biomarkers in caged or native fish. Furthermore, the paper systematically assesses the most common contaminants with the potential to affect fish liver tissue.
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Affiliation(s)
- Natalija Topić Popović
- Laboratory for Aquaculture Biotechnology, Ruđer Bošković Institute, Bijenička 54, Zagreb, Croatia.
- Centre of Excellence for Marine Bioprospecting-BioProCro, Ruđer Bošković Institute, Zagreb, Croatia.
| | - Lara Čižmek
- Laboratory for Aquaculture Biotechnology, Ruđer Bošković Institute, Bijenička 54, Zagreb, Croatia
- Centre of Excellence for Marine Bioprospecting-BioProCro, Ruđer Bošković Institute, Zagreb, Croatia
| | - Sanja Babić
- Laboratory for Aquaculture Biotechnology, Ruđer Bošković Institute, Bijenička 54, Zagreb, Croatia
- Centre of Excellence for Marine Bioprospecting-BioProCro, Ruđer Bošković Institute, Zagreb, Croatia
| | - Ivančica Strunjak-Perović
- Laboratory for Aquaculture Biotechnology, Ruđer Bošković Institute, Bijenička 54, Zagreb, Croatia
- Centre of Excellence for Marine Bioprospecting-BioProCro, Ruđer Bošković Institute, Zagreb, Croatia
| | - Rozelindra Čož-Rakovac
- Laboratory for Aquaculture Biotechnology, Ruđer Bošković Institute, Bijenička 54, Zagreb, Croatia
- Centre of Excellence for Marine Bioprospecting-BioProCro, Ruđer Bošković Institute, Zagreb, Croatia
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2
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Sousa S, Rocha MJ, Rocha E. Characterization and spatial relationships of the hepatic vascular–biliary tracts, and their associated pancreocytes and macrophages, in the model fish guppy ( Poecilia reticulata ): A study of serial sections by light microscopy. Tissue Cell 2018; 50:104-13. [DOI: 10.1016/j.tice.2017.12.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2017] [Revised: 12/17/2017] [Accepted: 12/27/2017] [Indexed: 12/23/2022]
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3
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Shen J, Yokota S, Yokoi H, Suzuki T. Diethylnitrosamine-induced expression of germline-specific genes and pluripotency factors, including vasa and oct4, in medaka somatic cells. Biochem Biophys Res Commun 2016; 478:858-63. [PMID: 27514449 DOI: 10.1016/j.bbrc.2016.08.039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 08/06/2016] [Indexed: 10/21/2022]
Abstract
Various methods have been developed to reprogram mammalian somatic cells into pluripotent cells as well as to directly reprogram somatic cells into other cell lineages. We are interested in applying these methods to fish, and here, we examined whether mRNA expression of germline-specific genes (vasa, nanos2, -3) and pluripotency factors (oct4, sox2, c-myc, nanog) is inducible in somatic cells of Japanese medaka (Oryzias latipes). We found that the expression of vasa is induced in the gut and regenerating fin by exposure to a carcinogen, diethylnitrosamine (DEN). Induction of vasa in the gut started on the 5th day of treatment with >50 ppm DEN. In addition, nanos2, -3, oct4, sox2, klf4, c-myc, and nanog were also expressed simultaneously in some vasa-positive gut and regenerating fin samples. Vasa-positive cells were detected by immunohistochemistry (IHC) in the muscle surrounding the gut and in the wound epidermis, blastema, and fibroblast-like cells in regenerating fin. In vasa:GFP transgenic medaka, green fluorescent protein (GFP) fluorescence appeared in the wound epidermis and fibroblast-like cells in the regenerating fin following DEN exposure, in agreement with the IHC data. Our data show that mRNA expression of genes relevant to germ cell specification and pluripotency can be induced in fish somatic cells by exposure to DEN, suggesting the possibility of efficient and rapid cell reprogramming of fish somatic cells.
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Affiliation(s)
- Jialing Shen
- Laboratory of Marine Life Science and Genetics, Graduate School of Agricultural Science, Tohoku University, Sendai 981-8555, Japan
| | - Shinpei Yokota
- Laboratory of Marine Life Science and Genetics, Graduate School of Agricultural Science, Tohoku University, Sendai 981-8555, Japan
| | - Hayato Yokoi
- Laboratory of Marine Life Science and Genetics, Graduate School of Agricultural Science, Tohoku University, Sendai 981-8555, Japan
| | - Tohru Suzuki
- Laboratory of Marine Life Science and Genetics, Graduate School of Agricultural Science, Tohoku University, Sendai 981-8555, Japan.
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Zheng X, Zhang X, Ding L, Lee JR, Weinberger PM, Dynan WS. Synergistic effect of high charge and energy particle radiation and chronological age on biomarkers of oxidative stress and tissue degeneration: a ground-based study using the vertebrate laboratory model organism Oryzias latipes. PLoS One 2014; 9:e111362. [PMID: 25375139 PMCID: PMC4222877 DOI: 10.1371/journal.pone.0111362] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2014] [Accepted: 09/29/2014] [Indexed: 11/19/2022] Open
Abstract
High charge and energy (HZE) particles are a main hazard of the space radiation environment. Uncertainty regarding their health effects is a limiting factor in the design of human exploration-class space missions, that is, missions beyond low earth orbit. Previous work has shown that HZE exposure increases cancer risk and elicits other aging-like phenomena in animal models. Here, we investigate how a single exposure to HZE particle radiation, early in life, influences the subsequent age-dependent evolution of oxidative stress and appearance of degenerative tissue changes. Embryos of the laboratory model organism, Oryzias latipes (Japanese medaka fish), were exposed to HZE particle radiation at doses overlapping the range of anticipated human exposure. A separate cohort was exposed to reference γ-radiation. Survival was monitored for 750 days, well beyond the median lifespan. The population was also sampled at intervals and liver tissue was subjected to histological and molecular analysis. HZE particle radiation dose and aging contributed synergistically to accumulation of lipid peroxidation products, which are a marker of chronic oxidative stress. This was mirrored by a decline in PPARGC1A mRNA, which encodes a transcriptional co-activator required for expression of oxidative stress defense genes and for mitochondrial maintenance. Consistent with chronic oxidative stress, mitochondria had an elongated and enlarged ultrastructure. Livers also had distinctive, cystic lesions. Depending on the endpoint, effects of γ-rays in the same dose range were either lesser or not detected. Results provide a quantitative and qualitative framework for understanding relative contributions of HZE particle radiation exposure and aging to chronic oxidative stress and tissue degeneration.
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Affiliation(s)
- Xuan Zheng
- Department of Neuroscience and Regenerative Medicine, Georgia Regents University, Augusta, Georgia, United States of America
- Center for Gene Diagnosis, Zhongnan Hospital, Wuhan University, Wuhan, China
| | - Xinyan Zhang
- Department of Biostatistics, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Lingling Ding
- Department of Anatomy and Embryology, Wuhan University School of Medicine, Wuhan, China
| | - Jeffrey R. Lee
- Department of Pathology, Georgia Regents University, Augusta, Georgia, United States of America
| | - Paul M. Weinberger
- Department of Otolaryngology and Center for Biotechnology & Genomic Medicine, Georgia Regents University, Augusta, Georgia, United States of America
| | - William S. Dynan
- Department of Neuroscience and Regenerative Medicine, Georgia Regents University, Augusta, Georgia, United States of America
- Departments of Radiation Oncology and Biochemistry, Emory University, Atlanta, Georgia, United States of America
- * E-mail:
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5
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Rhee JS, Lee JS. Whole genome data for omics-based research on the self-fertilizing fish Kryptolebias marmoratus. Mar Pollut Bull 2014; 85:532-541. [PMID: 24759509 DOI: 10.1016/j.marpolbul.2014.04.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 03/24/2014] [Accepted: 04/01/2014] [Indexed: 06/03/2023]
Abstract
Genome resources have advantages for understanding diverse areas such as biological patterns and functioning of organisms. Omics platforms are useful approaches for the study of organs and organisms. These approaches can be powerful screening tools for whole genome, proteome, and metabolome profiling, and can be used to understand molecular changes in response to internal and external stimuli. This methodology has been applied successfully in freshwater model fish such as the zebrafish Danio rerio and the Japanese medaka Oryzias latipes in research areas such as basic physiology, developmental biology, genetics, and environmental biology. However, information is still scarce about model fish that inhabit brackish water or seawater. To develop the self-fertilizing killifish Kryptolebias marmoratus as a potential model species with unique characteristics and research merits, we obtained genomic information about K. marmoratus. We address ways to use these data for genome-based molecular mechanistic studies. We review the current state of genome information on K. marmoratus to initiate omics approaches. We evaluate the potential applications of integrated omics platforms for future studies in environmental science, developmental biology, and biomedical research. We conclude that information about the K. marmoratus genome will provide a better understanding of the molecular functions of genes, proteins, and metabolites that are involved in the biological functions of this species. Omics platforms, particularly combined technologies that make effective use of bioinformatics, will provide powerful tools for hypothesis-driven investigations and discovery-driven discussions on diverse aspects of this species and on fish and vertebrates in general.
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Affiliation(s)
- Jae-Sung Rhee
- Department of Marine Science, College of Natural Science, Incheon National University, Incheon 406-772, South Korea
| | - Jae-Seong Lee
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon 440-746, South Korea.
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Browning ZS, Wilkes AA, Mackenzie DS, Patterson RM, Lenox MW. Using PET/CT imaging to characterize 18 F-fluorodeoxyglucose utilization in fish. J Fish Dis 2013; 36:911-919. [PMID: 23488673 DOI: 10.1111/jfd.12081] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Revised: 12/14/2012] [Accepted: 12/17/2012] [Indexed: 06/01/2023]
Abstract
Fish are becoming an increasingly important research species as investigators seek alternatives to mammalian models. Combined positron emission tomography/computed tomography with ¹⁸F-fluorodeoxyglucose (FDG-PET/CT) is a powerful new technology that has been extensively applied for high-resolution imaging in mammals but not fish. CT scanning provides detailed anatomical three-dimensional imaging. PET scanning detects areas of cellular activity using radio-labelled molecular probes with specific uptake rates appropriate to the tissue involved. FDG-PET is used in oncology because tissues with high glucose uptake, such as neoplasms, are intensely radio-labelled. PET/CT combines the two technologies, so that images acquired from both devices are merged into one superimposed image, thus more precisely correlating metabolic activity with anatomical three-dimensional imaging. Our objective was to determine if fish can be viable replacement animals in cancer studies using this technique by analysing the similarities between fish and humans in glucose uptake in select organs across multiple fish species. Rapid, quantifiable glucose uptake was demonstrated, particularly in brain, kidneys and liver in all imaged fish species. Standard uptake values for glucose uptake in the major organ systems of fish were more similar to those of humans than mice or dogs, indicating that fish may serve as effective alternative animal models using this technology. Applications for this technique in fish may include oncogenesis and metabolism studies as well as screening for environmental carcinogenesis.
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Affiliation(s)
- Z S Browning
- Comparative Medicine Program, Texas A&M University, College Station, TX, USA
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7
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Arana S, Alves VAF, Sabino M, Tabata YA, Nonogaki S, Zaidan-Dagli ML, Hernandez-Blazquez FJ. Immunohistochemical evidence for myofibroblast-like cells associated with liver injury induced by aflatoxin B1 in rainbow trout (Oncorhynchus mykiss). J Comp Pathol 2013; 150:258-65. [PMID: 24016778 DOI: 10.1016/j.jcpa.2013.07.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 04/24/2013] [Accepted: 07/06/2013] [Indexed: 12/22/2022]
Abstract
In mammalian species, profibrogenic cells are activated to become myofibroblasts in response to liver damage. Few studies have examined hepatic myofibroblasts and their role in liver damage in teleosts. The aim of the present study was to investigate the involvement of myofibroblast-like cells in rainbow trout (Oncorhynchus mykiss) with hepatic damage induced by aflatoxin B1 (AFB1). Histopathological and immunohistochemical analyses characterized alterations in the liver stroma during the carcinogenic process. Anti-human α-smooth muscle actin (SMA) and anti-human desmin primary antibodies were used in immunohistochemistry. Only the anti-SMA reagent labelled cells in trout liver. In the livers of control fish, only smooth muscle in blood vessels and around bile ducts was labelled. In the livers from AFB1-treated fish, SMA-positive cells were present in the stroma surrounding neoplastic lesions and in areas of desmoplastic reaction. These observations indicate that in teleosts, as in mammals, the myofibroblast-like cell is involved in fibrosis associated with liver injury. Chronic liver injury induced in trout by aflatoxin may provide a useful model system for study of the evolution of such mechanisms.
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Affiliation(s)
- S Arana
- Department of Histology and Embryology, Institute of Biology, University of Campinas (UNICAMP), CP: 6109, CEP: 13083-970 Campinas, São Paulo, Brazil.
| | - V A F Alves
- Department of Pathology, School of Medicine, São Paulo University, São Paulo
| | - M Sabino
- Adolfo Lutz Institute, São Paulo, Brazil
| | - Y A Tabata
- Estação Experimental de Salmonicultura Dr. Ascânio de Faria, APTA, Secretaria de Agricultura e Abastecimento de São Paulo, São Paulo, Brazil
| | - S Nonogaki
- Adolfo Lutz Institute, São Paulo, Brazil
| | - M-L Zaidan-Dagli
- Department of Pathology, School of Veterinary Medicine and Animal Sciences, São Paulo University, São Paulo, Brazil
| | - F J Hernandez-Blazquez
- Department of Surgery, School of Veterinary Medicine and Animal Science, São Paulo University, São Paulo, Brazil
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Van Wettere AJ, Law JM, Hinton DE, Kullman SW. Anchoring hepatic gene expression with development of fibrosis and neoplasia in a toxicant-induced fish model of liver injury. Toxicol Pathol 2012. [PMID: 23197195 DOI: 10.1177/0192623312464308] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Fish have been used as laboratory models to study hepatic development and carcinogenesis but not for pathogenesis of hepatic fibrosis. In this study, a dimethylnitrosamine-induced fish model of hepatic injury was developed in Japanese medaka (Oryzias latipes) and gene expression was anchored with the development of hepatic fibrosis and neoplasia. Exposed livers exhibited mild hepatocellular degenerative changes 2 weeks' postexposure. Within 6 weeks, hepatic fibrosis/cirrhosis was evident with development of neoplasia by 10 weeks. Stellate cell activation and development of fibrosis was associated with upregulation of transforming growth factor beta 1 (tgfb1), tgfb receptor 2, mothers against decapentaplegic homolog 3 (smad3a), smad3b, beta-catenin (ctnnb1), myc, matrix metalloproteinase (mmp2), mmp14a, mmp14b, tissue inhibitors of metalloproteinase (timp) 2a, timp2b, timp3, collagen type I alpha 1a (col1a1a), and col1a1b and a less pronounced increase in mmp13 and col4a1 expression. Tgfb receptor I expression was unchanged. Immunohistochemistry suggested that biliary epithelial cells and stellate cells were the main producers of TGF-β1. This study identified a group of candidate genes likely to be involved in the development of hepatic fibrosis and demonstrated that the TGF-β pathway likely plays a major role in the pathogenesis. These results support the medaka as a viable fish model of hepatic fibrosis.
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Affiliation(s)
- Arnaud J Van Wettere
- Department of Population Health and Pathobiology, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina 27607, USA.
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9
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Hobbie KR, DeAngelo AB, George MH, Law JM. Neoplastic and nonneoplastic liver lesions induced by dimethylnitrosamine in Japanese medaka fish. Vet Pathol 2011; 49:372-85. [PMID: 21724976 DOI: 10.1177/0300985811409443] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Small fish models have been used for decades in carcinogenicity testing. Demonstration of common morphological changes associated with specific mechanisms is a clear avenue by which data can be compared across divergent phyletic levels. Dimethylnitrosamine, used in rats to model human alcoholic cirrhosis and hepatic neoplasia, is also a potent hepatotoxin and carcinogen in fish. We recently reported some striking differences in the mutagenicity of DMN in lambda cII transgenic medaka fish vs. Big Blue(®) rats, but the pre-neoplastic and neoplastic commonalities between the two models are largely unknown. Here, we focus on these commonalities, with special emphasis on the TGF-β pathway and its corresponding role in DMN-induced hepatic neoplasia. Similar to mammals, hepatocellular necrosis, regeneration, and dysplasia; hepatic stellate cell and "spindle cell" proliferation; hepatocellular and biliary carcinomas; and TGF-β1 expression by dysplastic hepatocytes all occurred in DMN-exposed medaka. Positive TGF-β1 staining increased with increasing DMN exposure in bile preductular epithelial cells, intermediate cells, immature hepatocytes and fewer mature hepatocytes. Muscle specific actin identified hepatic stellate cells in DMN-exposed fish. Additional mechanistic comparisons between animal models at different phyletic levels will continue to facilitate the interspecies extrapolations that are so critical to toxicological risk assessments.
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Affiliation(s)
- K R Hobbie
- Integrated Laboratory Systems, Research Triangle Park, NC, USA
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10
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Padilla S, Cowden J, Hinton DE, Yuen B, Law S, Kullman SW, Johnson R, Hardman RC, Flynn K, Au DWT. Use of medaka in toxicity testing. ACTA ACUST UNITED AC 2011; Chapter 1:Unit1.10. [PMID: 20922755 DOI: 10.1002/0471140856.tx0110s39] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Small aquarium fishes are increasingly used as animal models, and one of these, the Japanese Medaka (Oryzias latipes), is frequently utilized for toxicity testing. While these vertebrates have many similarities with their terrestrial counterparts, there are differences that must be considered if these organisms are to be used to their highest potential. Commonly, testing may employ either the developing embryo or adults; both are easy to use and work with. To illustrate the utility and breadth of toxicity testing possible using medaka fish, we present protocols for assessing neurotoxicity in developing embryos, evaluating toxicant effects on sexual phenotype after treatment with endocrine-disrupting chemicals by sexual genotyping, and measuring hepatotoxicity in adult fish after treatment with a model hepatotoxicant. The methods run the gamut from immunohistology through PCR to basic histological techniques.
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Affiliation(s)
- Stephanie Padilla
- United States Environmental Protection Agency, Research Triangle Park, North Carolina, USA
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Abstract
A case of combined hepatocellular-cholangiocarcinoma (CHCC) in an adult male lesser flamingo (Phoenicopterus minor) that was part of a breeding programme at a private facility is reported. Grossly, the liver was markedly enlarged with multifocal, well-circumscribed, pinpoint to 2 cm diameter pale tan nodular masses. Histologically, the hepatic parenchyma was replaced by neoplastic cells that demonstrated hepatocellular and, less frequently, biliary epithelial cell differentiation. Positive pan-cytokeratin (AE1/AE3/PCK26) immunolabelling of the neoplastic cells forming bile ducts with the scattered immunoreactivity of cells forming glandular structures within the areas of hepatocellular differentiation supported the diagnosis. No metastases were detected. CHCC is a rare neoplasm in mammals and birds. This is the first report where gross, histological, and immunohistochemical characteristics of CHCC in a bird are described, and the first report of CHCC in a lesser flamingo.
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Affiliation(s)
- A J Van Wettere
- Center for Comparative Medicine and Translational Research, Raleigh, NC 27606, USA.
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Lauren DJ, Hinton D, Law M, Sorensen M, Lyndall J, Magar V, Nielsen M. Long-term trends in liver neoplasms in brown bullhead in the Buffalo River, New York, USA. Environ Toxicol Chem 2010; 29:1748-1754. [PMID: 20821628 DOI: 10.1002/etc.206] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The Buffalo River area of concern (AOC) was assigned an impaired status for the fish tumors and other deformities beneficial use impairment category by the New York State Department of Environmental Protection in 1989. This was initially based on an inadequately documented brown bullhead (Ameiurus nebulosus) feeding study using river sediment extracts. The presence of liver tumors was subsequently supported by reports of a 19 to 27% prevalence in wild brown bullhead between 1983 and 1988 and a 4.8% prevalence in 1998. However, neither fish size (or age) nor sample locations were given, and histopathological definitions were inconsistent in these previous studies. Therefore, in 2008, we re-evaluated the prevalence of hepatocellular and chloangiocellular tumors (as well as other gross indicators of fish health) in brown bullhead averaging 25 cm in length collected from three reaches of the Buffalo River and recorded our collection sites by global positioning system. Among the 37 fish of appropriate size collected, only three exhibited liver tumors (8%). The tumors were evenly distributed within the three reaches, and only hepatocellular tumors were found. There were no differences in the prevalence of hepatic foci of alteration, body weight, length, or hepatosomatic index among the three reaches, but the conditions factor was significantly lower in fish from reach 2. Natural attenuation of water and sediment quality are the most likely causes for the decrease in liver tumors. The prevalence of liver tumors between 1998 and 2008 in the Buffalo River is similar to that found in recovery-stage AOCs and some Great Lakes reference areas.
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Affiliation(s)
- Darrel J Lauren
- ENVIRON International, 1760 Market Street, Philadelphia, Pennsylvania 19038, USA.
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Howarth DL, Hagey LR, Law SHW, Ai N, Krasowski MD, Ekins S, Moore JT, Kollitz EM, Hinton DE, Kullman SW. Two farnesoid X receptor alpha isoforms in Japanese medaka (Oryzias latipes) are differentially activated in vitro. Aquat Toxicol 2010; 98:245-255. [PMID: 20430454 PMCID: PMC2874645 DOI: 10.1016/j.aquatox.2010.02.020] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2009] [Revised: 02/15/2010] [Accepted: 02/16/2010] [Indexed: 05/26/2023]
Abstract
The nuclear receptor farnesoid X receptor alpha (FXRalpha, NR1H4) is activated by bile acids in multiple species including mouse, rat, and human and in this study we have identified two isoforms of Fxralpha in Japanese medaka (Oryzias latipes), a small freshwater teleost. Both isoforms share a high amino acid sequence identity to mammalian FXRalpha (approximately 70% in the ligand-binding domain). Fxralpha1 and Fxralpha2 differ within the AF1 domain due to alternative splicing at the fourth intron-exon boundary. This process results in Fxralpha1 having an extended N-terminus compared to Fxralpha2. A Gal4DBD-FxralphaLBD fusion construct was activated by chenodeoxycholic, cholic, deoxycholic and lithocholic acids, and the synthetic agonist GW4064 in transient transactivation assays. Activation of the Gal4DBD-FxralphaLBD fusion construct was enhanced by addition of PGC-1alpha, as demonstrated through titration assays. Surprisingly, when the full-length versions of the two Fxralpha isoforms were compared in transient transfection assays, Fxralpha2 was activated by C(24) bile acids and GW4064, while Fxralpha1 was not significantly activated by any of the compounds tested. Since the only significant difference between the full-length constructs was sequence in the AF1 domain, these experiments highlight a key functional region in the Fxralpha AF1 domain. Furthermore, mammalian two-hybrid studies demonstrated the ability of Fxralpha2, but not Fxralpha1, to interact with PGC-1alpha and SRC-1, and supported our results from the transient transfection reporter gene activation assays. These data demonstrate that both mammalian and teleost FXR (Fxralpha2 isoform) are activated by primary and secondary bile acids.
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Affiliation(s)
- Deanna L Howarth
- Integrated Toxicology and Environmental Health Program and Nicholas School of the Environment and Earth Sciences, Duke University, Durham, NC 27708, USA
| | - Lee R Hagey
- Department of Medicine, University of California at San Diego, La Jolla, CA 92093, USA
| | - Sheran H W Law
- Department of Environmental and Molecular Toxicology, North Carolina State University, Raleigh, NC 27695, USA
| | - Ni Ai
- Department of Pharmacology, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, Piscataway, NJ 08854, USA
| | - Matthew D Krasowski
- Department of Pathology, University of Iowa Hospitals and Clinics, Iowa City, IA, USA
| | - Sean Ekins
- Department of Pharmacology, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, Piscataway, NJ 08854, USA; Collaboration in Chemistry, Jenkintown, PA 19046, USA; Department of Pharmaceutical Sciences, University of Maryland, Baltimore, MD 21201, USA
| | - John T Moore
- GlaxoSmithKline Discovery Research, Research Triangle Park, NC 27709, USA
| | - Erin M Kollitz
- Department of Environmental and Molecular Toxicology, North Carolina State University, Raleigh, NC 27695, USA
| | - David E Hinton
- Integrated Toxicology and Environmental Health Program and Nicholas School of the Environment and Earth Sciences, Duke University, Durham, NC 27708, USA
| | - Seth W Kullman
- Department of Environmental and Molecular Toxicology, North Carolina State University, Raleigh, NC 27695, USA.
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Hobbie KR, Deangelo AB, King LC, Winn RN, Law JM. Toward a molecular equivalent dose: use of the medaka model in comparative risk assessment. Comp Biochem Physiol C Toxicol Pharmacol 2009; 149:141-51. [PMID: 18722551 DOI: 10.1016/j.cbpc.2008.07.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2008] [Revised: 07/29/2008] [Accepted: 07/29/2008] [Indexed: 12/01/2022]
Abstract
Recent changes in the risk assessment landscape underscore the need to be able to compare the results of toxicity and dose-response testing between a growing list of animal models and, quite possibly, an array of in vitro screening assays. How do we compare test results for a given compound between vastly different species? For example, what dose level in the ambient water of a small fish model would be equivalent to 10 ppm of a given compound in the rat's drinking water? Where do we begin? To initially address these questions, and in order to compare dose-response tests in a standard rodent model with a fish model, we used the concept of molecular dose. Assays that quantify types of DNA damage that are directly relevant to carcinogenesis integrate the factors such as chemical exposure, uptake, distribution, metabolism, etc. that tend to vary so widely between different phyletic levels. We performed parallel exposures in F344 rats and Japanese medaka (Oryzias latipes) to the alkylating hepatocarcinogen, dimethylnitrosamine (DMN). In both models, we measured the DNA adducts 8-hydroxyguanine, N(7)-methylguanine and O(6)-methylguanine in the liver; mutation frequency using lambda cII transgenic medaka and lambda cII transgenic (Big Blue(R)) rats; and early morphological changes in the livers of both models using histopathology and immunohistochemistry. Pulse dose levels in fish were 0, 10, 25, 50, or 100 ppm DMN in the ambient water for 14 days. Since rats are reported to be especially sensitive to DMN, they received 0, 0.1, 1, 5, 10, or 25 ppm DMN in the drinking water for the same time period. While liver DNA adduct concentrations were similar in magnitude, mutant frequencies in the DMN-exposed medaka were up to 20 times higher than in the Big Blue rats. Future work with other compounds will generate a more complete picture of comparative dose response between different phyletic levels and will help guide risk assessors using "alternative" models.
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Affiliation(s)
- Kristen R Hobbie
- Comparative Biomedical Sciences Program and Center for Comparative Medicine and Translational Research, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606, USA
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Hardman R, Kullman S, Yuen B, Hinton DE. Non invasive high resolution in vivo imaging of alpha-naphthylisothiocyanate (ANIT) induced hepatobiliary toxicity in STII medaka. Aquat Toxicol 2008; 86:20-37. [PMID: 18022256 PMCID: PMC2724681 DOI: 10.1016/j.aquatox.2007.09.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2007] [Revised: 09/13/2007] [Accepted: 09/21/2007] [Indexed: 05/25/2023]
Abstract
A novel transparent stock of medaka (Oryzias latipes; STII), homozygous recessive for all four pigments (iridophores, xanthophores, leucophores, melanophores), permits transcutaneous, high resolution (<1 microm) imaging of internal organs and tissues in living individuals. We applied this model to in vivo investigation of alpha -naphthylisothiocyanate (ANIT) induced hepatobiliary toxicity. Distinct phenotypic responses to ANIT involving all aspects of intrahepatic biliary passageways (IHBPs), particularly bile preductular epithelial cells (BPDECs), associated with transitional passageways between canaliculi and bile ductules, were observed. Alterations included: attenuation/dilation of bile canaliculi, bile preductular lesions, hydropic vacuolation of hepatocytes and BPDECs, mild BPDEC hypertrophy, and biliary epithelial cell (BEC) hyperplasia. Ex vivo histological, immunohistochemical, and ultrastructural studies were employed to aid in interpretation of, and verify, in vivo findings. 3D reconstructions from in vivo investigations provided quantitative morphometric and volumetric evaluation of ANIT exposed and untreated livers. The findings presented show for the first time in vivo evaluation of toxicity in the STII medaka hepatobiliary system, and, in conjunction with prior in vivo work characterizing normalcy, advance our comparative understanding of this lower vertebrate hepatobiliary system and its response to toxic insult.
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Affiliation(s)
- Ron Hardman
- Duke University, Nicholas School of the Environment and Earth Sciences, Durham, NC 27708, USA.
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Hardman RC, Volz DC, Kullman SW, Hinton DE. An in vivo look at vertebrate liver architecture: three-dimensional reconstructions from medaka (Oryzias latipes). Anat Rec (Hoboken) 2007; 290:770-82. [PMID: 17516461 DOI: 10.1002/ar.20524] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Understanding three-dimensional (3D) hepatobiliary architecture is fundamental to elucidating structure/function relationships relevant to hepatobiliary metabolism, transport, and toxicity. To date, factual information on vertebrate liver architecture in 3 dimensions has remained limited. Applying noninvasive in vivo imaging to a living small fish animal model we elucidated, and present here, the 3D architecture of this lower vertebrate liver. Our investigations show that hepatobiliary architecture in medaka is based on a polyhedral (hexagonal) structural motif, that the intrahepatic biliary system is an interconnected network of canaliculi and bile-preductules, and that parenchymal architecture in this lower vertebrate is more related to that of the mammalian liver than previously believed. The in vivo findings presented advance our comparative 3D understanding of vertebrate liver structure/function, help clarify previous discrepancies among vertebrate liver conceptual models, and pose interesting questions regarding the "functional unit" of the vertebrate liver.
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Affiliation(s)
- Ron C Hardman
- Duke University, Nicholas School of the Environment and Earth Sciences, Durham, North Carolina 27708, USA
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Kissling GE, Bernheim NJ, Hawkins WE, Wolfe MJ, Jokinen MP, Smith CS, Herbert RA, Boorman GA. The Utility of the Guppy (Poecilia reticulata) and Medaka (Oryzias latipes) in Evaluation of Chemicals for Carcinogenicity. Toxicol Sci 2006; 92:143-56. [PMID: 16581948 DOI: 10.1093/toxsci/kfj181] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
There has been considerable interest in the use of small fish models for detecting potential environmental carcinogens. In this study, both guppies (Poecilia reticulata) and medaka (Oryzias latipes) were exposed in the aquaria water to three known rodent carcinogens for up to 16 months. Nitromethane, which caused mammary gland tumors by inhalation exposure in female rats, harderian gland and lung tumors in male and female mice, and liver tumors in female mice by inhalation, failed to increase tumors in either guppies or medaka. Propanediol, which when given in the feed was a multisite carcinogen in both sexes of rats and mice, caused increased liver tumors in male guppies and male medaka. There was reduced survival in female guppies and no increased tumors in female medaka. 1,2,3-Trichloropropane, which when administered by oral gavage was a multisite carcinogen in both sexes of rats and mice, caused an increased incidence of tumors in the liver of both male and female guppies and medaka and in the gallbladder of male and female medaka. The results of this study demonstrate that for these three chemicals, under these specific exposure conditions, the fish appear less sensitive and have a narrower spectrum of tissues affected than rodents. These results suggest that fish models are of limited utility in screening unknown chemicals for potential carcinogenicity.
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Affiliation(s)
- Grace E Kissling
- Environmental Medicine and Diseases Program and Environmental Toxicology Program, National Institute of Environmental Health Sciences, 111 T.W. Alexander Drive, Research Triangle Park, NC 27709, USA.
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Tilton SC, Gerwick LG, Hendricks JD, Rosato CS, Corley-Smith G, Givan SA, Bailey GS, Bayne CJ, Williams DE. Use of a Rainbow Trout Oligonucleotide Microarray to Determine Transcriptional Patterns in Aflatoxin B1-Induced Hepatocellular Carcinoma Compared to Adjacent Liver. Toxicol Sci 2005; 88:319-30. [PMID: 16141433 DOI: 10.1093/toxsci/kfi309] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide, and its occurrence is associated with a number of environmental factors including ingestion of the dietary contaminant aflatoxin B(1) (AFB(1)). Research over the last 40 years has revealed rainbow trout (Oncorhynchus mykiss) to be an excellent research model for study of AFB(1)-induced hepatocarcinogenesis; however, little is known about changes at the molecular level in trout tumors. We have developed a rainbow trout oligonucleotide array containing 1672 elements representing over 1400 genes of known or probable relevance to toxicology, comparative immunology, carcinogenesis, endocrinology, and stress physiology. In this study, we applied microarray technology to examine gene expression of AFB(1)-induced HCC in the rainbow trout tumor model. Carcinogenesis was initiated in trout embryos with 50 ppb AFB(1), and after 13 months control livers, tumors, and tumor-adjacent liver tissues were isolated from juvenile fish. Global gene expression was determined in histologically confirmed HCCs compared to noncancerous adjacent tissue and sham-initiated control liver. We observed distinct gene regulation patterns in HCC compared to noncancerous tissue including upregulation of genes important for cell cycle control, transcription, cytoskeletal formation, and the acute phase response and downregulation of genes involved in drug metabolism, lipid metabolism, and retinol metabolism. Interestingly, the expression profiles observed in trout HCC are similar to the transcriptional signatures found in human and rodent HCC, further supporting the validity of the model. Overall, these findings contribute to a better understanding of the mechanism of AFB(1)-induced hepatocarcinogenesis in trout and identify conserved genes important for carcinogenesis in species separated evolutionarily by more than 400 million years.
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Affiliation(s)
- Susan C Tilton
- Department of Environmental & Molecular Toxicology, Oregon State University, Corvallis, 97331, USA
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Mizgireuv IV, Majorova IG, Gorodinskaya VM, Khudoley VV, Revskoy SY. Carcinogenic effect of N-nitrosodimethylamine on diploid and triploid zebrafish (Danio rerio). Toxicol Pathol 2005; 32:514-8. [PMID: 15603536 DOI: 10.1080/01926230490496311] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Viability of polyploid organisms in lower vertebrates including fish provides an additional tool to investigate genetic mechanisms of neoplastic transformation caused by carcinogens. Here we present data on differential sensitivity of diploid and triploid zebrafish (Danio rerio) to N-nitrosodimethylamine (NDMA) induced hepatocarcinogenesis. The effect of the carcinogen was studied in 100 diploid and 120 triploid zebrafish. Zebrafish, age 5-6 weeks, were exposed to 50 ppm NDMA for 8 weeks and then were transferred into fresh carcinogen-free water until necropsy. At the necropsy performed 24 weeks after beginning the treatment, cholangiolar tumors (cholangiocarcinomas and cholangiomas) were essentially observed in diploid zebrafish only, while the incidence of hepatocellular tumors (hepatocellular carcinomas and adenomas) was similar in diploid and triploid zebrafish, 7.7% and 9.5%, respectively. By contrast, 36 weeks after beginning the treatment, the incidence of hepatocellular tumors was significantly lower in diploid animals as compared to triploid ones, 10.3% and 33.8%, respectively. The incidence of cholangiolar tumors in diploid and triploid zebrafish was not significantly different, 10.3% and 14.9%, respectively. Therefore, the increase of ploidy appeared to have a differential effect on the induction of these 2 types of liver tumors in zebrafish. This finding suggests a difference in genetic mechanisms of the tumor development revealed by utilization of triploid animals in this study. However, triploid zebrafish demonstrated an overall increase in latency period in the development of both types of hepatic tumors, a finding that can be interpreted as an increased resistance of triploid animals to the carcinogenic effect of NDMA.
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Affiliation(s)
- Igor V Mizgireuv
- Laboratory of Genetic Toxicology, N. N. Petrov Research Institute of Oncology, St. Petersburg 197758, Russia
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Hinton DE, Kullman SW, Hardman RC, Volz DC, Chen PJ, Carney M, Bencic DC. Resolving mechanisms of toxicity while pursuing ecotoxicological relevance? Mar Pollut Bull 2005; 51:635-48. [PMID: 16154600 DOI: 10.1016/j.marpolbul.2005.07.020] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
In this age of modern biology, aquatic toxicological research has pursued mechanisms of action of toxicants. This has provided potential tools for ecotoxicologic investigations. However, problems of biocomplexity and issues at higher levels of biological organization remain a challenge. In the 1980s and 1990s and continuing to a lesser extent today, organisms residing in highly contaminated field sites or exposed in the laboratory to calibrated concentrations of individual compounds were carefully analyzed for their responses to priority pollutants. Correlation of biochemical and structural analyses in cultured cells and tissues, as well as the in vivo exposures led to the production and application of biomarkers of exposure and effect and to our awareness of genotoxicity and its chronic manifestations, such as neoplasms, in wild fishes. To gain acceptance of these findings in the greater environmental toxicology community, "validation of the model" versus other, better-established often rodent models, was necessary and became a major focus. Resultant biomarkers were applied to heavily contaminated and reference field sites as part of effects assessment and with investigations following large-scale disasters such as oil spills or industrial accidents. Over the past 15 years, in the laboratory, small aquarium fish models such as medaka (Oryzias latipes), zebrafish (Danio rerio), platyfish (Xiphophorus species), fathead minnow (Pimephales promelas), and sheepshead minnow (Cyprinodon variegatus) were increasingly used establishing mechanisms of toxicants. Today, the same organisms provide reliable information at higher levels of biological organization relevant to ecotoxicology. We review studies resolving mechanisms of toxicity and discuss ways to address biocomplexity, mixtures of contaminants, and the need to relate individual level responses to populations and communities.
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Affiliation(s)
- David E Hinton
- Laboratory of Molecular Aquatic Toxicology, Division of Environmental Sciences and Policy, Nicholas School of the Environment and Earth Sciences, Duke University Durham, NC 277-8-0328, USA.
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Affiliation(s)
- David E Hinton
- Division of Environmental Sciences and Policy, Nicholas School of the Environment and Earth Sciences, Duke University, Durham, North Carolina 27708-0328, USA
| | - Yuko Wakamatsu
- Laboratory of Freshwater Fish Stocks, Bioscience Center, Nagoya University, Nagoya, Japan
| | - Kenjiro Ozato
- Laboratory of Freshwater Fish Stocks, Bioscience Center, Nagoya University, Nagoya, Japan
| | - Shosaku Kashiwada
- Division of Environmental Sciences and Policy, Nicholas School of the Environment and Earth Sciences, Duke University, Durham, North Carolina 27708-0328, USA
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Abstract
Fish have a long history of use in cancer toxicology studies, because they develop neoplasms that are histologically similar to human cancers. Because of considerable progress in zebrafish genetics and genomics over the past few years, the zebrafish system has provided many useful tools for studying basic biological processes. These tools include forward genetic screens, transgenic models, specific gene disruptions and small-molecule screens. By combining carcinogenesis assays, genetic analyses and small-molecule screening techniques, the zebrafish is emerging as a powerful system for identifying novel cancer genes and for cancer drug discovery.
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Affiliation(s)
- Howard M Stern
- Howard Hughes Medical Institute, Children's Hospital of Boston, 300 Longwood Avenue, Enders 761, Boston, Massachusetts 02115, USA.
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Davis CR, Okihiro MS, Hinton DE. Effects of husbandry practices, gender, and normal physiological variation on growth and reproduction of Japanese medaka, Oryzias latipes. Aquat Toxicol 2002; 60:185-201. [PMID: 12200085 DOI: 10.1016/s0166-445x(02)00004-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Japanese medaka, Oryzias latipes, are currently used in a variety of research applications for toxicological and carcinogenesis research, yet the impact of certain husbandry factors on study outcome has received limited attention. In this study, we demonstrated significant effects of stocking density (SD), dietary restriction (DR) and photoperiod on somatic growth in medaka. Higher stocking densities significantly inhibited somatic and hepatic growth in females, while having no similar effects on males. Daily egg production declined in a step-wise manner in groups of fish stocked at densities ranging from 0.38 to 2.6 fish per l. Significantly slower somatic growth was observed in fish fed on a mildly restrictive dietary protocol compared with those fish fed to excess. Further significant declines were observed in somatic growth of fish fed at a rate comparable to that used in research studies (3-4% body weight (BW) per day). Fish reared at an 8-h light:16-h dark (8L/16D) photoperiod were significantly smaller than cohorts reared at a 16-h light:8-h dark (16L/8D) photoperiod and female sexual maturity was delayed in the short photoperiod cohort. In normal female medaka, a high degree of individual variation was observed in daily egg production, as well as diurnal fluctuations in ovarian weight, gonadosomatic index (GSI) and hepatosomatic index (HSI). These results indicate some husbandry factors affect growth, sexual maturation and egg production in medaka and should be taken into consideration in studies evaluating endpoints that may be impacted by growth and reproductive performance, i.e. carcinogenesis and endocrine disruption studies. The high degree of individual variation among normal females and daily fluctuations in organ weights should also be considered in study design.
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Affiliation(s)
- Corrine R Davis
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, One Shields Ave, Davis, CA 95616, USA.
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