Download or read book Gene Expression in the Liver of Rainbow Trout Oncorhynchus Mykiss During the Stress Response written by Tracey S. Momoda and published by . This book was released on 2006 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: The extent to which responses to stress are maladaptive or adaptive to the long-term survival of fish remains to be better understood. The aim of this study was to identify differentially expressed genes in the livers of rainbow trout, Oncorhynchus mykiss, responding to an experimental stressor. Gene expression responses were measured using an oligonucleotide microarray specific for Oncorhynchus mykiss, to highlight genes responding to a stressor and to serve as a basis for hypothesis development. We conducted replicate experiments at two different times. In both experiments, fish exposed to a three-hour stressor were compared to control (unstressed) fish. In the second experiment, there were additional treatments of fish that were exposed to only a half-hour of stress and of fish sampled 21 hours after experiencing a three-hour stressor. This 21 hour post-stress treatment was a means to study gene expression during recovery from stress. Plasma cortisol was measured to document the physiological stress response of the fish. Real-time PCR (qPCR) of candidate genes was used to validate the microarray findings. In both experiments the microarray revealed many genes with differential expression after three hours of stress. The genes we report as differentially expressed met a criteria of at least a 1.4 fold change and a statistical difference (p=0.05) from control levels of expression. Among these, five genes responded similarly in both experiments, suggesting that they are robust indicators of stress. These genes are a major histocompatibility complex class I molecule (MHCI), JunB, glucose 6-phosphatase (G6Pase), nuclear protein 1 (Nupr1) and tumor necrosis factor decoy receptor (TNFDR). Interestingly, transcripts of Nupr1 did not return to control levels in the 21 hours after stress. In fact, the transcripts continued to increase during recovery.

Download or read book Differential Expression of Growth Genes in the Liver and White Muscle of Small and Large Rainbow Trout Oncorhynchus Mykiss Produced in Two Seasons and Co localization with Quantitative Trait Loci written by Andrea Kocmarek and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effects of Environmental Stressors on Cardiac Gene Expression and Contractility in Rainbow Trout Oncorhynchus Mykiss written by Tracey S. Momoda and published by . This book was released on 2014 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rainbow trout (Oncorhynchus mykiss) experience a variety of stressors in their natural environment as well as in aquaculture that can have negative effects on their physiology. The effects of physiological stress and endocrine disruption have been well described in fish. However, there is a scarcity of information on the effects of such stressors on the heart in fish. We examined gene expression in the rainbow trout heart in response to 17[alpha]-ethinylestradiol (EE), the active ingredient in some oral contraceptives, as well as physiological stress. We also assessed contractile function, as a measure of cardiac performance, under conditions of increasing performance demands in sexually immature rainbow trout. In chapter 2, using qRT-PCR, we observed increased vitellogenin (vtg1) in the ventricle, along with, hepatic estrogen receptor (ER[alpha]) and vtg1 mRNA increased with EE exposure, confirming endocrine disruption in both tissues. Stress increased corticotropin-releasing factor receptor 1 (CRF-R1) and JunB in response to stress while nuclear protein 1 (nupr1) and glucocorticoid receptor (GCR2) expression increased only in the population with higher cortisol levels (>100 ng/ml) in response to stress. Interestingly, EE exposure did not affect stress induced gene expression and stress did not have an effect on EE induced gene expression in the heart of rainbow trout. This research highlights the fact that these stressors have the potential to have physiological impacts beyond the target tissues classically thought of for stress (i.e. HPI/A axis) or exposure to estrogenic compounds (i.e. HPG axis). In chapter 3, contractile force production was measured from ventricle strips exposed to increasing concentrations of Ca2 or epinephrine to simulate conditions of increasing performance. Also, to determine the effects of physiological stress, ventricle strips were pre-treated with 100 ng/L cortisol prior to increasing Ca2 or epinephrine. Ventricle strips from males had a greater contractile force production to increasing Ca2+ or epinephrine compared to females, at concentrations greater than 3.5 mM Ca2+ or 1 [micro]M epinephrine. Exposure to cortisol did not have a direct effect on contractility, nor did it have an effect the contractile response to increasing exogenous Ca2+ in either sex. Interestingly, force production did not vary by sex in the cortisol pre-treated exposed to epinephrine, suggesting a sex-dependent response. My findings suggest that there are sex differences in the contractile function in rainbow trout and that these may be modified under conditions related to physiological stress. The rainbow trout is a genetically diverse species found across a variety of habitats. Our results highlight the variation in responses in in contractile function and gene expression in the heart by the different sexes, as well as variation within and among populations that allow rainbow trout to adapt and perform in the presence of stressors in the environment.

Download or read book A Study on the Growth Hormone regulated Gene Expression of C EBP Isoforms and Their Relationship with IGF ll Gene Expression in the Liver of Rainbow Trout Oncorhynchus Mykiss written by Hung-Chieh Lo and published by . This book was released on 2009 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Heat Shock Protein Expression in the Rainbow Trout Oncorhynchus Mykiss Heart in Response to Separate Heat and Hypoxic Stress written by Eryn Creamer and published by . This book was released on 2007 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Regulation of Heat Shock Protein 70 Levels in Red Blood Cells of Rainbow Trout written by Lynsi Henrickson and published by . This book was released on 2010 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt: The physiological responses to stressor exposure can be broadly grouped into the organismal and the cellular stress responses. The organismal stress response involves the release of hormones into general circulation, while the cellular stress response involves the synthesis of proteins, the most important being the heat shock proteins (HSPs), which play a role in maintaining protein homeostasis. Elevated HSP70 expression in response to stressors has been demonstrated in trout (Oncorhynchus mykiss) red blood cells (RBCs). The ease of repeated sampling of blood suggests the possibility of using this tissue as a non-lethal marker of cellular stress in fish. This study tested the hypothesis that stressor exposure will elevate HSP70 expression in trout RBCs and the role of stress hormones in mediating this response. Acute heat shock exposure (+12oC) significantly elevated plasma cortisol, glucose and lactate levels in heat shocked fish over 24 h. A tissue-specific response was seen in HSP70 expression in liver, brain, gill and RBCs. To enable measurement of RBC HSP70 concentrations, an enzyme-linked immunosorbent assay (ELISA) was developed using a commercially available rabbit anti-salmon HSP70 and a recombinant chinook salmon (Oncorhynchus tshawytscha) HSP70. To determine effects of chronic exposure, two studies were conducted exposing trout to either cadmium (0, 0.75 or 2.0 [mu]g/L over 28 d) or municipal wastewater effluent (0, 20 or 90% over 14 d). However, neither exposure elicited a significant HSP70 response. Effects of stress hormones on RBC HSP70 levels were tested by exposing cells in vitro to either cortisol (10 and 100 ng/mL) or epinephrine (10 nM) with or without heat shock. Heat shock elevated HSP70 content in trout RBCs but no modulation by stress hormones was seen. It was shown for the first time that RBCs release HSP70 content into the medium in response to an acute heat shock and this release is attenuated by stress hormones. Overall, HSP70 levels in RBCs have the potential to be a reliable non-lethal marker of acute cellular stress effects in fish. The release of HSP70 from RBCs leads to the hypothesis that HSP70 may also have an extracellular role in fish, and warrants further study.

Download or read book Biology of Stress in Fish written by Carl B. Schreck and published by Academic Press. This book was released on 2016-11-01 with total page 604 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biology of Stress in Fish: Fish Physiology provides a general understanding on the topic of stress biology, including most of the recent advances in the field. The book starts with a general discussion of stress, providing answers to issues such as its definition, the nature of the physiological stress response, and the factors that affect the stress response. It also considers the biotic and abiotic factors that cause variation in the stress response, how the stress response is generated and controlled, its effect on physiological and organismic function and performance, and applied assessment of stress, animal welfare, and stress as related to model species. Provides the definitive reference on stress in fish as written by world-renowned experts in the field Includes the most recent advances and up-to-date thinking about the causes of stress in fish, their implications, and how to minimize the negative effects Considers the biotic and abiotic factors that cause variation in the stress response

Download or read book Characterization and Expression of Rainbow Trout Oncorhynchus Mykiss Growth Hormone Family Genes written by Bih-Ying Yang and published by . This book was released on 1997 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Heat Shock Proteins and Physiological Stress in Redband Rainbow Trout Oncorhynchus Mykiss Gairdneri in the South Fork John Day River Oregon written by Joseph W. Feldhaus and published by . This book was released on 2006 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of this research was to characterize thermal habitat requirements for juvenile redband steelhead trout (Oncorhynchus mykiss gairdneri) in the South Fork John Day River (SFJD), Oregon using physiological indicators of fish condition. Physiological indices of fish condition measured were whole body lipid content and heat shock proteins, specifically hsp70. Hsp70 is a family of highly conserved molecular chaperones proteins that protect cellular function by preventing irreversible protein damage. Hsp70 levels were measured in liver, white muscle, and fin tissue. This thesis includes a study of passive integrated transponder (PIT) tag handling stress in juvenile rainbow trout. PIT tags are used to identify individual fish. The objectives of the PIT tag study were to determine if there is a stress response, measured as a difference in plasma cortisol levels, between PIT tagged and non-PIT tagged rainbow trout (O. mykiss), to determine if PIT tag-related stress induces hepatic hsp70 synthesis in juvenile rainbow trout, and to examine the relation between cortisol and hsp70 levels. There was a difference in plasma cortisol six hours after tagging, with both treatment and tank effects. There were no differences detected after the 24h sampling period. Plasma cortisol levels were highly variable, but changes in plasma cortisol did not alter hepatic hsp70 levels. A laboratory experiment demonstrated that hsp70 levels increase significantly between 19 and 22ðC in both fin and liver tissue. The finding that hsp70 can be quantified in fin tissue is significant because it provides a non-lethal technique for assessing thermal stress in rare or endangered fish. The response of hsp70 in relation to temperature was sigmoid. During the summers of 2004 and 2005, a field study in the SFJD was conducted. The objectives were to: (1) determine if SFJD redband rainbow trout experience thermal stress, (2) develop a non-lethal technique for measuring cellular hsp70 levels, (3) and characterize the relation between whole body lipids and hsp70 for fish in the SFJD. Maximum hsp70 levels in liver and white muscle tissue in field collected fish occurred when mean weekly maximum temperatures (MWMT) exceeded 22-23ðC. Short and long term stream temperature averages of 15.6-18.2ðC and temperature maximums of 18.8-21.6ðC significantly increased hsp70 levels in liver tissue. Both the hsp72 and hsp73 isoforms were significantly elevated in white muscle tissue when long and short term average stream temperatures were 16-18.5ðC and 19.6-23ðC for temperature maximums. Lipid levels began to decrease when MWMT exceeded 23ðC. Results of this research suggest increased cellular hsp70 levels in juvenile redband rainbow trout in the SFJD River is symptomatic of cellular stress related to thermal conditions, as are decreasing lipid levels. Measurement of cellular hsp70 levels provides another tool that can be used to characterize physiological suitability of thermal habitat and potentially to define thermal limits, as differences of 1 or 2°C are sufficient to change expression of thermal stress proteins detected using these techniques. When using hsp70 as an index of thermal stress in different O. mykiss subpopulations, differences in hsp70 expression between tissues should be considered.

Download or read book Neuroendocrine immune Interactions written by Rolf C. Gaillard and published by Karger Medical and Scientific Publishers. This book was released on 2002 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: Interactions between the immune, endocrine and nervous systems seldom appear as main issues in the neurosciences and in immunology. So far this was most likely due to the need to focus on the molecular and cellular bases of single neural, endocrine and immune processes. But hormones, neurotransmitters and neuropeptides can also influence more subtle mechanisms underlying immune cell activity. The contents of this volume aim at listing some aspects which show that not only the bases for neuroendocrine control of more refined mechanisms related to the organization and functioning of the immune systems to exist, but also that the immune system can actively communicate with neuroendocrine structures. The evidence is divided into three categories: - Anatomical, cellular and molecular bases for the exchange of information between immune, endocrine and neural cells, - reciprocal effects between immune and neuroendocrine mechanisms, and - immune-neuroendocrine regulatory circuits. Immunologically triggered neuroendocrine responses can be either beneficial or deleterious for the host. A systematic approach would imply the simultaneous evaluation of neuroendocrine and immune parameters and thus provide the basis for therapeutic interventions based on antagonizing or blocking undesirable effects.

Download or read book The Stress Response of Rainbow Trout Oncorhynchus Mykiss Exposed to Lead written by Kenneth A. Phillips and published by . This book was released on 1997 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Amino Acids Regulate Hepatic Intermediary Metabolism related Gene Expression Via MTORC1 dependent Manner in Rainbow Trout Oncorhynchus Mykiss written by Dai Weiwei and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: During my doctoral study, we used rainbow trout, a representative carnivorous fish and relevant diabetic model, to study the mechanisms underlying the regulation of hepatic intermediary metabolism by nutrients (amino acids (AAs) and glucose), and determine the potential involvement of insulin/Akt and mTORC1 signaling pathways in these regulations. Using acute administration of rapamycin, a pharmacological inhibitor of TOR, we first identified that mTORC1 activation promotes the expression of genes related to fatty acid biosynthesis, glycolysis and amino acid catabolism, while Akt negatively regulates gluconeogenic gene expression in rainbow trout liver and primary hepatocytes. Furthermore, we demonstrated hepatic fatty acid biosynthetic gene expression is more responsive to dietary protein intake/AAs than dietary carbohydrate intake/glucose during acute stimulations in vivo and in vitro. Moreover, we further showed that high levels of AAs up-regulate hepatic fatty acid biosynthetic gene expression through an mTORC1-dependent manner, while excessive AAs attenuate insulin-mediated repression of gluconeogenesis through elevating IRS-1 Ser302 phosphorylation, which in turn impairs Akt phosphorylation and dampens insulin action. Finally, using glucose tolerance test and acute inhibition of rapamycin, we concluded that hepatic gluconeogenesis probably plays a major role in controlling glucose homeostasis, which maybe account for the prolonged hyperglycemia and glucose intolerance phenotype of carnivorous fish. The present thesis brings forward our understandings about the roles of protein/AAs in the regulation of hepatic intermediary metabolism in trout and identifies relevant cellular signaling pathways mediating the action of amino acids on metabolism. It also clarifies some nutritional characteristics of the trout.

Download or read book Liver Gene Expression During Vitellogenesis in Male Rainbow Trout written by Kenneth R. Lawless and published by . This book was released on 1987 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Consistency in the stress response of individuals of two strains of rainbow trout Oncorhynchus mykiss written by T G (Tom) Pottinger and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Functional Genomics in Aquaculture written by Marco Saroglia and published by John Wiley & Sons. This book was released on 2012-05-25 with total page 435 pages. Available in PDF, EPUB and Kindle. Book excerpt: Genomics has revolutionized biological research over the course of the last two decades. Genome maps of key agricultural species have offered increased understanding of the structure, organization, and evolution of animal genomes. Building upon this foundation, researchers are now emphasizing research on genome function. Published with the World Aquaculture Society, Functional Genomics in Aquaculture looks at the advances in this field as they directly relate to key traits and species in aquaculture production. Functional Genomics in Aquaculture opens with two chapters that provide a useful general introduction to the field of functional genomics. The second section of the book focuses on key production traits such as growth, development, reproduction, nutrition, and physiological response to stress and diseases. The final five chapters focus on a variety of key aquaculture species. Examples looking at our understanding of the functional genomes of salmonids, Mediterranean sea bass, Atlantic cod, catfish, shrimp, and molluscs, are included in the book. Providing valuable insights and discoveries into the functional genomes of finfish and shellfish species, Functional Genomics in Aquaculture, will be an invaluable resource to researchers and professionals in aquaculture, genetics, and animal science.

Download or read book Assessing Mechanisms of Immunotoxicity for Polycyclic Aromatic Hydrocarbons in Rainbow Trout Oncorhynchus Mykiss written by Claudia F. Bravo and published by . This book was released on 2005 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the past 30 years, numerous studies have focused on the toxicities of polycyclic aromatic hydrocarbons (PAH). Laboratory and field studies have helped elucidate the detrimental effects of these chemicals on growth, reproduction and immune response. Polycyclic aromatic hydrocarbons are in the priority list of chemicals to be studied by different governmental agencies and universities and understanding their mechanisms of action is the focus of the current research. The manuscripts presented in this dissertation are focused on the effects and mechanism of action of PAH on disease susceptibility. After a dietary exposure to PAH for up to 50 days (chapter II) and samplings after 3, 7, 14, 28 and 50 days, a number of biomarkers of PAH exposure were measured: Fluorescent aromatic compounds (FACs) in bile, ethoxyresorufin-o-deethylase (EROD) in liver microsomes, cytochrome P450 1A immunohistochemistry in liver and kidney and adduct formation in liver. Additionally markers of oxidative stress were measured: comet assay in blood, protein nitration in kidney and F2-isoprostanes in kidney. Oxidative stress was a probable factor in PAH induced responses in fish adapted to long-term PAH exposures and aryl hydrocarbon activation was not necessarily involved in this process. Disease challenge with Aeromonas salmonicida (chapter III) resulted in differences in mortalities that demonstrated that fish exposed to PAH were more susceptible to disease than fish not exposed to PAH. Determination of gene expression in head kidney of fish exposed and not exposed to PAH challenged with A. salmonicida using microarray and RT-PCR technologies 2, 4, 10 and 20 days after challenge (chapter IV), suggested that PAH exposure was associated with down regulation of interleukin 8, transport associated protein 1, NF-kB modulator, recombination activating gene and major histocompatibility complex II two days after challenge in fish exposed to PAH. The transcript levels were closer to control levels 20 days after challenge, this indicated a recovery from the effect of PAH exposure.

Download or read book Fish Oil Replacement and Alternative Lipid Sources in Aquaculture Feeds written by Giovanni M. Turchini and published by CRC Press. This book was released on 2010-07-19 with total page 542 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experts are predicting that demand for marine fish oil will soon outstrip supply, creating extreme urgency within the global aquafeed industry to find viable alternatives. Fish Oil Replacement and Alternative Lipid Sources in Aquaculture Feeds is the first comprehensive review of this multifaceted, complex issue. It also addresses the crucial quest