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 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 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 Die wirtschaftliche Integration Europas written by and published by . This book was released on 1957 with total page 101 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Environmental Factors Regulating Gene Expression in Fish written by Susanna Airaksinen and published by . This book was released on 2003 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modulation of Extracellular Heat Shock Protein 70 Levels in Rainbow Trout written by Leslie Erin Faught and published by . This book was released on 2013 with total page 77 pages. Available in PDF, EPUB and Kindle. Book excerpt: At the cellular level, the stress response involves the synthesis of a highly conserved family of heat shock proteins (Hsps). These proteins are essential for maintenance of cellular homeostasis, both in times of stress and in normal cell functioning. Some of the most abundant forms of Hsps in the cell are members of the 70 kDa family. Intracellular heat shock protein 70 (Hsp70) expression in response to proteotoxicity is a highly conserved cellular stress response, but little is known about the role of extracellular Hsp70 (eHsp70) in fish. In order to begin characterizing eHsp70 in fish, the hypothesis that an acute stressor will elevate plasma Hsp70 levels in rainbow trout (Oncorhynchus mykiss) was tested. Subsequent in vitro studies examined whether eHsp70 level was modulated by cortisol and if this involved the action of the glucocorticoid receptor (GR), a ligand-activated transcription factor. The effect of cortisol on the eHsp70 response is important to consider because this steroid is elevated as a result of stressor exposure to allow for short-term allocation of energy stores to cope with stress. Cortisol is the primary corticosteroid in fish and exerts its main effects by binding to either GR or mineralocorticoid receptors (MR). Furthermore, eHsp70 has been previously implicated as having important immunoregulatory roles in mammalian models, but nothing has yet been reported in fish. To this end, a hypothesis tested here was that eHsp70 levels will increase after exposure to the bacterial endotoxin lipopolysaccharide (LPS), and that this response is modulated by cortisol. Finally, research on the effects of exogenous Hsp70 has not been reported in lower vertebrates; however, the relevance of this protein in intercellular signaling, especially in regards to immune regulation, is gaining increasing importance in mammalian models. Therefore, an experiment to determine whether Hsp70 would elicit upregulation of key immunoregulatory cytokines was also conducted. To accurately measure the low levels of Hsp70 in the plasma, a competitive antibody-capture enzyme-linked immunosorbent assay (ELISA) was developed. In the in vivo study, fish exposed to an acute heat shock (1h at 10°C above ambient temperature) exhibited a significant elevation in red blood cell Hsp70 levels over a 24 h period. There was also a significant increase in plasma Hsp70 levels at 4 h, but not at 24 h post-heat shock. To more specifically determine how cortisol affected the release of Hsp70, in vitro studies using primary cultures of hepatocytes demonstrated that cortisol significantly decreased eHsp70 levels in the medium at 24 h when compared with untreated controls, and this response was abolished in the presence of a GR antagonist, mifepristone (RU486). This result for the first time established a link between cortisol signaling and eHsp70 release in any animal model. When hepatocytes were exposed to LPS in vitro, eHsp70 levels were significantly lower in the LPS (30 [mu]g/ml) group; however, heat shock abolished this effect at 24 h. Though eHsp70 levels in the heat shocked hepatocytes treated with low-dose LPS (10 [mu]g/ml) was similar to untreated control levels, high-dose LPS treated hepatocytes showed significant elevation of eHsp70 levels above the low dose group. The ability of LPS to modulate eHsp70 release was not observed to be further regulated by cortisol. While this work suggests the modulation of eHsp70 by LPS, the physiological role remains to be elucidated. Finally when hepatocytes were exposed to exogenous Hsp70, there was no effect on key immunoregulatory genes (IL-1[beta] and IL-8) transcript levels; however, the effect of this protein remains to be tested using other cell systems, including immune cells in fish. Overall, eHsp70 concentration was measured in trout plasma using a competitive ELISA and demonstrates for the first time that stressor exposure affects plasma eHsp70 levels in fish. Furthermore, cortisol, the primary corticosteroid in teleosts, modulates eHsp70 release in trout hepatocytes and this is action is mediated by GR signaling. Also, while trout hepatocytes secrete eHsp70 in response to endotoxin shock, a role for eHsp70 in eliciting an immune response is not clear in lower vertebrates. Taken together the results from this study suggest a role for eHsp70 in acute stress adaptation in fish, but the target tissues involved and the physiological responses remain to be elucidated. Further work on the effects of eHsp70 on target tissues effects, and the mechanisms involved, may have important implications in our understanding of the role of this stress protein in cell signaling and stress adaptation in fish.
Download or read book Temperature Stress Results in a Coordinated and Development dependent Expression Profile of Heat Shock Proteins and Ubiquitin in Rainbow Trout Oncorhynchus Mykiss written by Jillian Rendell and published by . This book was released on 2006 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effects of Social Stress on the Heat Shock Response in Rainbow Trout Oncorhynchus Mykiss written by Stephen Middleton and published by . This book was released on 2010 with total page 72 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 Heat Shock Proteins in Signaling Pathways written by Alexzander A. A. Asea and published by Springer. This book was released on 2019-07-09 with total page 482 pages. Available in PDF, EPUB and Kindle. Book excerpt: Signaling pathways is a comprehensive mechanism by which all cellular organisms communicate internally and externally with their microenvironment. This is a highly complex and exact process. Errors in signaling pathways and in the processing of cellular information are known to be responsible for the majority of diseases including cancer, inflammatory and neurological disorders. Knowledge gained from the better understanding of signaling pathways will help in elucidating disease processes and will assist in development and design of novel targeted treatment therapies to combat human diseases and disorders. Heat shock proteins (HSP) are uniquely involved in a number of critical signaling pathways. Key basic and clinical research laboratories from major universities, academic medical hospitals, biotechnology and pharmaceutical laboratories around the world have contributed chapters that review present research activity and importantly project the field into the future. The book is a must read for graduate students. medical students, basic science researchers and postdoctoral scholars in the fields of Translational Medicine, Clinical Research, Human Physiology, Biotechnology, Cell & Molecular Medicine, Pharmaceutical Scientists and Researchers involved in Drug Discovery.
Download or read book An Integrative Approach to Stress in the Rainbow Trout Oncorhynchus Mykiss written by Sacha LeBlanc and published by . This book was released on 2011 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cumulated Index Medicus written by and published by . This book was released on 2000 with total page 1796 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2004 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stress Protein Expression and Metabolism in the Heart of the Rainbow Trout written by Judah Goldstein and published by . This book was released on 2005 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Environmental Correlates of Heat Shock Protein Expression in Teleost Fish written by Claire Michelle Carpenter and published by . This book was released on 1999 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Expression and Function of the Small Heat Shock Protein Hsp27 During Embryogenesis of Zebrafish Danio Rerio written by Alexey Ustyugov and published by . This book was released on 2007 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:
