Source: UNIV OF HAWAII submitted to
PHYSIOLOGICAL EFFECTS OF ENVIRONMENTAL STRESSORS IN A KEY FINFISH FOR AQUACULTURE
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
1013306
Grant No.
(N/A)
Project No.
HAW02051-H
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Aug 5, 2017
Project End Date
Sep 30, 2021
Grant Year
(N/A)
Project Director
Seale, AN.
Recipient Organization
UNIV OF HAWAII
3190 MAILE WAY
HONOLULU,HI 96822
Performing Department
Human Nutrition, Food & Animal Sciences
Non Technical Summary
With the increased pressure on global fish populations, demand for sustainable aquaculture has risen dramatically. Developing and maintaining a safe and sustainable seafood supply, therefore is of critical importance. The farming of fish such as tilapia, which can feed lower in the food chain and can adapt to a variety of environmental conditions, provides an advantage in production and cost. Tilapia are also the second most commercially aquacultured species, after carp, and our studies on the endocrine physiology of growth and development in this species are aimed at improving rearing conditions that can be applied in the aquaculture industry. The neuroendocrine system regulates development and physiology in fish and coordinates their interactions with their environment. Our studies are based on the idea that growth and environmental adaptation are regulated through the orderly release of hormones by the neuroendocrine system, which integrates information from genes and the environment. We have found that salinity fluctuations between fresh water and seawater can increase growth rates in tilapia. Through our studies we will be able to determine how different environmental stressors, such as salinity and temperature, have an effect on growth and provide first-hand knowledge on increasing growth rates and thereby production of fish farmers in Hawaii and the Pacific region, while diminishing the reliance on costly fresh water resources.
Animal Health Component
100%
Research Effort Categories
Basic
80%
Applied
0%
Developmental
20%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
3053714102050%
3063714102050%
Goals / Objectives
Our overarching goal is to determine the effects of environmental and handling stressors, including endocrine dirupting chemicals, temperature and salinity, on the physiological stress response, growth, and osmoregulation in tilapia. Addressing this goal shall lead to the elucidation of some of the mechanisms that mediate the endocrine regulation of growth, osmoregulation and development in tilapia acclimated to a range of environmental conditions. We propose to determine the length of time that tidally-reared fish need to be exposed to tidally-changing salinities to achieve practical and significant increases in growth relative to fish reared in steady-state FW and SW, and whether such growth is affected by temperature. Ultimately, these approaches will determine whether the acquisition of characteristics that favor growth in specific temperature and salinity regimes, for example, takes place developmentally, during rearing, or require permanent exposure to such regimes during adulthood. The focus of our approach is to examine the underlying endocrine and metabolic drivers associated with enhanced growth under a range of environmental conditions. We shall determine whether growth is linked to the activation of the GH/IGF system and to a reduction in metabolic rate associated with a reduced cost of osmoregulation. To approach these questions, we shall rear yolk-sac tilapia in tidally-changing salinities under ambient and high temperatures for 30, or 60 days and then transfer the fish to steady-state salinities. Specifically our objectives are:Objective 1: To determine the capacity of tidally-changing rearing salinities and temperature to alter growth and feed efficiency in larval, juvenile, and adult tilapiaObjective 2: To characterize the effect of rearing salinity and temperature on pituitary GH, and PRL mRNA expression, circulating GH, IGF-1, PRL and cortisol levels and branchial expression of effectors of ion transport.Objective 3: To characterize the effect of rearing salinity and temperature on the muscular, hepatic and branchial expression of GH receptors, IGF-1 and IGF-2, IGF receptor, and IGF binding proteins.While these objectives address our broader scope of investigating the effects of environmental stressors on the physiology of tilapia, modifications to these specific objectives may be necessary based on preliminary results and availability of funding. For example, additional environmental stressors, endpoints, and species shall be added to the original scope of the project as funding and time permits. Of particular interest are: 1) investigation of whether early exposure of tilapia fry to endocrine disrupting chemicals (EDCs) that are known to be pervasive in the aquatic environment in Hawaii may impart later effects on growth under the experimental conditions described; 2) measurement of additional endpoints and pathways associated with growth such as myostatin and Akt/mTOR; and 3) extension of these studies beyond our proposed model species to include comparisons with additional tilapia species and strains that are widely employed in commercial production.
Project Methods
Tilapia fry will be obtained from FW and SW broodstock populations currently maintained at the Hawai?i Institute of Marine Biology. The experiment shall be conducted in a new fish rearing facility currently under construction at the Magoon Research Station, University of Hawai?i. Fish will be reared in temperature-controlled outdoor tanks (400 L), under natural photoperiod. Water temperatures will be maintained at either 24-26°C (low temperature) or 31-33 °C (high temperature). Animals will be fed twice daily with commercially available diets formulated for tilapia. Fry will be acclimated to FW, SW, or subjected to intermittent salinity changes under a tidal regimen (TR). Salinity in the tanks subjected to the TR will be switched from FW to SW every 6 h.Adressing Objective 1, weight of the feed consumed by the fish will be determined daily by subtracting the dry feed weight remaining after feeding from the initial feed weight. The wet weight of all fish will be measured bi-weekly for the duration of the experiment. Survival rate (%) at each sampling period will be measured by dividing the final number of fish by the initial number of fish and multiplying by 100. Growth parameters (specific growth rate, daily weight gain, condition factor, and gonadosomatic index) will be measured and pituitary, liver, muscle, and gill samples will be collected at 60, 120, 180, and 240 days. Blood will be collected at 120, 180, and 240 days, but not at 60 days, due to fish size and the volume required for estimation of circulating hormone levels. Tissues will be flash-frozen in liquid nitrogen and kept at -80°C until total RNA extraction. Plasma will be separated immediately and stored at -80°C until quantification of PRL, IGF-1, GH, and cortisol by RIA. Plasma osmolality will be measured using a vapor pressure osmometer.Over the past several years we have developed the tools that allow for the simultaneous measurement of key components of the tilapias endocrine system. These tools include: radioimmunoassays for measuring blood plasma levels of GH, PRL, IGF-1 and cortisol, and real-time quantitative polymerase chain reactions to measure tissue mRNA levels of GH, IGF-1, IGF-2, GH- receptors (GHR1 and GHR2), IGF receptor (IGFR) and IGF binding proteins (IGFBPs), and several effectors of ion transport, including NCC, NKCC, NHE3, CFTR and NKA. We shall apply a combination of these techniques to analyze the samples obtained in the experimental design (Fig. 1) and address Objectives 2 and 3.MethodsRadioimmunoassay: Plasma PRL, IGF-1 and GH will be estimated by RIA as validated and widely employed in our studies. Tilapia PRLs and GH will be purified in collaboration with Prof. Shunsuke Moriyama (see letter of collaboration) and iodinated by chloramine-T. Plasma cortisol will be measured by RIA employing 3H-labelled cortisol and anti-cortisol antibody (Fitzgerald Industries, North Acton, MA).Real-time quantitative reverse transcriptase PCR: Total RNA will be extracted from the gill filaments using Tri-reagent (MRC), and then reverse transcribed using a cDNA reverse transcription kit (Life Technologies). Primer pairs forGH, PRL177, PRL188, GHR1, GHR2, PRLR1, IGF-1, IGF-2, NHE3, NKCC, NCC, NKAa-1a, NKAa-1b,CFTR , b-actin;, EF1-a will be used as described in our previous publications. Primer pairs for IGFR and IGFBPs will be developed from partial mRNA sequences identified in the tilapiine EST database in GenBank by using BLAST similarity search. Expression of these genes will be normalized by 18S, b-actin or EF1-a . PCR reaction will contain 0.2 µM of each primer and 12 µl of SYBR Green PCR Master Mix (Life Technologies) in a 15 ml reaction volume. The cycling parameter will be as follows: 2 min at 95oC followed by 40 cycles of 95oC for 15 sec and 60oC for 1 min using the StepOnePlus real-time PCR system (Life Technologies).The PI will utilize the proposed research to mentor undergraduate, graduate, and post-doctoral students, including those of underrepresented minorities. Results will be presented at national and international symposia and published in peer-reviewed journals of this field. Results will also be transferred to fish farmers through extension with the overall goal of increasing fish growth to improve the economic and environmental sustainability of finfish aquaculture. While the objectives of the proposal are ambitious, they are achievable within five years with sufficient funding. The timing, order and design of experiments will depend on the funding available and on the results of our ongoing research.

Progress 08/05/17 to 09/30/21

Outputs
Target Audience:During the duration of the project, wereached out todiverseaudiencesthroughclasses, invited lectures, workshops, local and international symposia. Audiences were composed of undergraduate students, graduate students, commercial producers, fishpond practitioners, scientists, extension faculty in a range of fieldsencompassing agricultural sciencesand fish biology. Moreover, some audiences included the general public at large, beyond those with an interest in aquaculture and fish physiology. Specific information on the dissemination of the workis more specifically reported under "products". Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?This project has provided opportunities for the training of 11 undergraduate students, 6 graduate students and 1 research specialist in a range of disciplines, ranging from tilapia broodstock and tank maintenance to experimental design, data analysis, presentation skills and sample collection. These skills provide first-hand experience with practices and techniques involved in aquaculture facilities and research. Studentswere also trained in critical thinking skills, interpretation of the scientific literature, experimental design, basic molecular biology techniques, and oral presentation skills. They all presented their work to their peers and professors at local symposia and conferences. Three of the undergraduate students continued in the lab to pursue graduate studies; one M.Sc. graduate has finished Medical school and residency, another is pursuing Veterinary school and another recent graduate is now working on aquaculture extension activities. How have the results been disseminated to communities of interest?Results have been presented locally through invited lectures, workshops, and national and international research symposia. The presentations disseminated in these venues are listed under "Products" and "Target Audience". Moreover, the results of this project have been incorporated into the curricula of undergraduate classes thought by PI Seale at University of Hawaii, including "advanced topics in animal sciences", "comparative endocrinology" and "aquaculture production". What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Overall, we have studied the effects of environmental and handling stressors, including temperature and salinity, on the physiological stress response, growth, and osmoregulation of Mozambique tilapia a suitable model organism for both aquaculture and biomedical research. We elucidated some of the mechanisms that mediate the regulation of growth, osmoregulation and development in organisms acclimated to a range of environmental conditions. By understanding these mechanisms, it was possible to obtain invaluable information for the production of aquaculture species that range from salinity tolerance to growth rates and developmental effects of endocrine disrupting chemicals. Collectively, this information shall help advance multiple aspects of aquaculture research and contribute to the best management practices for fish production. Specifically, addressing Objective 1, we conducted studies on Mozambique tilapia on: 1) the effects of growth hormone (GH) on the gene expression of nutrient transporters in three intestinal segments; 2) effects of sex, salinity, and sampling period on pituitary growth hormone expression; 3) effects of tidally-changing salinities on growth parameters and feed conversion efficiency, including body weight and GH expression; and 4) effects of temperature on the release of prolactin (Prl) a pleiotropic hormone that is essential for freshwater acclimation in Mozambique tilapia. On the first experiment, our findings indicate that GH supports growth, at least in part, by stimulating the gene expression of its receptor and key nutrient transporters in the intestine. In the second study, we found that sex-specific patterns in GH expression is modulated by salinity regime and daylight period in Mozambique tilapia. In the third study, we found that tidally-changing salinities increase growth rates through the upregulation of pituitary GH, while reducing FCR at certain periods of grow-out. Last, we found that a rise in temperature induces the release of Prl from dispersed Prl cells, in vitro. On Objective 2, we further evaluated growth, stress and osmoregulatory endpoints in response to environmental conditions, including environmental stressors of anthropogenic origin such as endocrine disrupting chemicals (EDCs). We reported on 5) the effects of early larval waterborne exposure to nonylphenol and estrogen on endpoints of growth and reproduction at the adult stage; 6) we conducted a comprehensive literature review of experimental approaches for determining the effects of endocrine-disrupting chemicals; 7) we measured circulating cortisol and glucose in response to distinct salinity regimes; 8) we analyzed the transcription of multiple effectors of ion transport in kidney, urinary bladder and gill, including ncc and nkcc; and 9) we began characterizing the transcription factors underlying the regulation of Prl genes in response to extracellular osmolality in Mozambique tilapia. On Objective 3, we analyzed the GH-IGF axis along with reproductive markers more specifically in response to environmental stressors such as salinity and EDC exposure. We analyzed the effects of: 10) tidally changing salinities on IGFs, GH and PRL receptors and 11) larval EDC exposure on muscle and hepatic IGF1 and 2, GH receptor, hepatic estrogen receptor and vitellogenin expression. On Objective 2 and 3 our main findings indicate that tilapia exposed to estradiol and nonylphenol at concentrations found in the environment as yolk-sac fry, exhibit subsequent changes to the endocrine systems regulating growth and reproductive functions. Changes in salinity with a tidal cycle transiently increase cortisol levels, through after 1 week, levels subside to those of baseline salinity conditions. Glucose levels, on the other hand, are elevated during transfer to fresh water or during the fresh water phase of the tidal cycle. Tidally changing salinities also upregulate hepatic and muscular IGFs and GH receptor, indicating a likely path for the observed increases in growth rates in tidal conditions. Finally, our most recent studies have unraveled the pituitary-specific promoters involved in hormonal regulation by temperature and salinity variations, and furthered our understanding of how prolactin cells mediate temperature changes. We have also reported on the effects of salinity acclimation on the thyroid axis and expression of deiodinases and are also investigating the hormonal basis of sexual dimorphism in tilapia by measuring the effects of pituitary hormones on growth-related genes in the liver, gonad, and muscle of male and female Mozambique tilapia.

Publications

  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2021 Citation: Seale, A.P. (2021). A prolactin cell model to study sensory transduction of environmental stimuli in fish. Genes and Animal Biology, Department of Human Nutrition, Food and Animal Sciences, University of Hawai?i. Virtual (Oct 12).
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2021 Citation: Lerner, D.T., Okimoto, D.K., Tagarino, K.A., Sudnovsky, M., Seale, A.P., Haws, M., M., Ellis, S. (2021) Establishing a Hawai?i-Pacific Consortium: A Revitalization and Expansion of an Aquaculture Development Program. Advanced Aquaculture Collaboratives (Hubs) Sea Grant NOAA Aquaculture Research Symposium. Virtual Meeting (Nov 1-3).
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Inokuchi, M., Moorman, B., Yamaguchi, Y., Seale, A.P. (2021). Age-dependent decline in salinity tolerance in a euryhaline fish. Front. Aging. 2: 15.
  • Type: Journal Articles Status: Accepted Year Published: 2021 Citation: Breves, J.P., Nelson, N.N., Koltenyuk, V., Petro-Sakuma, C., Celino-Brady, F.T., Seale, A.P. (2021) Enhanced expression of ncc1 and clc2c in the kidney and urinary bladder accompanies freshwater acclimation in Mozambique tilapia. Comp. Biochem. Physiol. 260: 111021; doi: 10.1016/j.cbpa.2021.111021
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Seale, L.A., Gilman, C.L., Zavacki, A.M., Larsen, P.R., Inokuchi, M., Breves, J.P., Seale, A.P. (2021) Regulation of thyroid hormones and branchial iodothyronine deiodinases during freshwater acclimation in tilapia. Mol. Cell. Endocrinol. 538: 111450. doi: 10.1016/j.mce.2021.111450
  • Type: Journal Articles Status: Under Review Year Published: 2021 Citation: Woo, D.W., Malintha, G.H.T., Celino-Brady, F.T., Yamaguchi, Y., Breves, J. P., Seale, A.P. (2021). Tilapia prolactin cells are thermosensitive osmoreceptors. Res. Square. Preprint; https://doi.org/10.21203/rs.3.rs-993437/v1
  • Type: Theses/Dissertations Status: Published Year Published: 2021 Citation: Woo, D.W. (2021). Thermally-induced changes in cell volume and hormone release in prolactin cells of Mozambique tilapia (Oreochromis mossambicus) M.Sc. in Animal Sciences, University of Hawaii at M?noa, Honolulu, Hawaii.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2021 Citation: Malintha, G.M.T, Celino-Brady, F.T., Seale, A.P. (2021) How do fish detect salinity changes? Clues from the molecular regulation of the prolactin gene. The 45th annual Albert L. Tester Memorial Symposium, Virtual Meeting (Apr 20-23).
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2021 Citation: Woo, D.W., Malintha, G.M.T, Celino-Brady, F.T., Seale, A.P. (2021) Do fish sense and respond to changes in temperature and salt concentration in similar ways? Clues from the endocrine system. The 45th annual Albert L. Tester Memorial Symposium, Virtual Meeting (Apr 20-23).
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2021 Citation: E. Barba, E. Conklin, D. Kraft, I. Knapp, A. Seale, R. Toonen (2021) Aquaculture applications of Poolseq: Scanning genomes for traces of salinity tolerance. The 45th annual Albert L. Tester Memorial Symposium, Virtual Meeting (Apr 20-23).
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2021 Citation: Celino-Brady, F.T., Breves, J.P., Seale, A.P. (2021) Sex-dependent modulation of genes involved in growth and reproduction by growth hormone and luteinizing hormone in tilapia. 6th Biennial Conference of the North American Society for Comparative Endocrinology. Virtual Meeting (May 25-27).
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2021 Citation: Woo, D.W., Malintha, G.H.T., Celino-Brady, F.T., Breves, J.P., Yamaguchi, Y., Seale, A.P. (2021) Thermally-induced changes in cell volume and hormone release in prolactin cells of Mozambique tilapia. 6th Biennial Conference of the North American Society for Comparative Endocrinology. Virtual Meeting (May 25-27).
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2021 Citation: Malintha, G.H.T., Celino-Brady, F.T., Seale, A.P. (2021) Osmotic regulation of transcription factor mRNA levels in prolactin cells of Mozambique tilapia. 6th Biennial Conference of the North American Society for Comparative Endocrinology. Virtual Meeting (May 25-27).
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2021 Citation: Seale, A.P., Seale, L.A., Gilman, C.L, Zavacki, A.M., Larsen, P.R., Inokuchi, M., Breves, J.P. (2021) Effects of freshwater acclimation on thyroid hormones and branchial deiodinases in Mozambique tilapia. 6th Biennial Conference of the North American Society for Comparative Endocrinology. Virtual Meeting (May 25-27).
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2021 Citation: Seale, A.P. (2021). A fish model to investigate the endocrine integration of environmental stimuli. Seminar in Biomedical Sciences, Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawai?i. Virtual (Aug 30).


Progress 10/01/19 to 09/30/20

Outputs
Target Audience:During the current reporting period, we have presented to diverse audiences through classes and invited lectures, local and international symposia. Audiences were composed of graduate students, scientists, extension faculty in a range of fields encompassing agricultural sciences and fish biology through the following national and international venues. Information was disseminated through the conferences and symposia reported under "products". Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?During the current reporting period, the project has provided opportunities for the training of 1 undergraduate student, 3 graduate students and 1 research specialist in a range of disciplines, ranging from tilapia broodstock and tank maintenance to experimental design, data analysis, presentation skills and sample collection. These skills provide first-hand experience with practices and techniques involved in aquaculture facilities and research. How have the results been disseminated to communities of interest?Results have been disseminated locally through invited lectures, national and international research symposia and through workshops. The presentations disseminated in these venues are listed under "Products" and "Target Audience". What do you plan to do during the next reporting period to accomplish the goals?We shall continue improvements on our research infrastructure and conduct the sampling of ongoing experiments, especially those under Objective 3.

Impacts
What was accomplished under these goals? We presented data gathered from addressing Objectives 1 and 2 and beyond in a variety of venues listed under "Products", mainly the World Aquaculture Society conference held in Honolulu in 2020, and published the results in a diversity peer-reviewed journals, namely Aquaculture, General and Comparative Endocrinology, Journal of Neuroendocrinology, and Frontiers in Endocrinology. Briefly, we conducted experiments which include studies on 1) the effects of salinity regime on the stress response in tilapia; 2) effects of sex, salinity, and sampling period on pituitary growth hormone expression in Mozambique tilapia; 3) molecular regulation of the osmoregulatory hormone prolactin in Mozambique tilapia; and 4) a comprehensive review on the experimental approaches for determining the effects of endocrine-disrupting chemicals. Our current studies are unraveling the pituitary specific promoters involved in hormonal regulation by temperature and salinity variations, and further our understanding of how prolactin cells mediate temperature changes. We are also investigating the hormonal basis of sexual dimorphism in tilapia by measuring the effects of pituitary hormones on growth-related genes in the liver, gonad, and muscle of male and female Mozambique tilapia.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Celino-Brady, F.T., Petro-Sakuma, C.K., Breves, J.P., Lerner, D.T., and Seale, A.P. 2020. Estrogenic chemical pollutants affect growth and reproduction-related genes in male Mozambique Tilapia, Oreochromis mossambicus. Aquaculture America 2020, Honolulu, Hawaii (Feb 10).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Seale, A.P., Petro-Sakuma, C.K., Celino-Brady, F.T., and Breves, J.P. 2020. Growth hormone regulates intestinal nutrient transporters in Mozambique tilapia Oreochromis mossambicus. Aquaculture America 2020, Honolulu, Hawaii (Feb 10).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Seale, A. P. 2020. From live cell imaging to radioimmunoassays to animal facilities: approaches in tilapia research. International mini-symposium: Approaches for experimental challenges in aquaculture research, University of Hawai?i at M?noa (Jan 15).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Celino-Brady, F.T., Pavlosky, K.K., Lerner, D.T., and Seale, A.P. 2020. Sex, salinity, and sampling period modulate growth hormone expression in Mozambique Tilapia Oreochromis mossambicus. Aquaculture America 2020, Honolulu, Hawaii.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Chang, R., Celino-Brady, F.T., Breves, J.P., and Seale, A.P. 2020. Regulation of growth and reproductive genes by pituitary hormones in male and female Mozambique Tilapia (Oreochromis mossambicus). Aquaculture America 2020, Honolulu, Hawaii.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2020 Citation: Woo, D.W., Celino-Brady, F.T., Pavlosky, K.K., Lerner, D.T., and Seale, A.P. 2020. Effects of environmental salinity on the stress response in Mozambique tilapia, Oreochromis mossambicus. Aquaculture America 2020, Honolulu, Hawaii.
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Celino-Brady, F., Lerner, D.T., and Seale, A.P. 2020. Experimental Approaches for Characterizing the Endocrine Disrupting Effects of Environmental Chemicals in Fish. Front. Endocrinol. doi: 10.3389/fendo.2020.619361
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Seale, A.P., Malintha, T., Celino-Brady, F.T., Head, T., Belcaid, M, Yamaguchi, Y., Lerner, D.T., Baltzegar, D.A., Borski, R.J., Stoytcheva, Z.R., and Breves, J.P. 2020. Transcriptional regulation of prolactin in a euryhaline teleost: characterization of gene promoters through in silico and transcriptome analyses. J. Neuroendocrinol. 32: e12905.
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Petro-Sakuma, C.K., Celino-Brady, F., Breves, J.P., and Seale, A.P. 2020. Growth hormone regulates intestinal gene expression of nutrient transporters in tilapia, Oreochromis mossambicus. Gen. Comp. Endocrinol. 292: 113464.
  • Type: Journal Articles Status: Published Year Published: 2020 Citation: Seale, A.P., Pavlosky, K.K., Celino-Brady, F., and Lerner, D.T. 2020. Sex, salinity and sampling period dependent patterns of growth hormone mRNA expression in Mozambique tilapia. Aquaculture. 519: 734766.


Progress 10/01/18 to 09/30/19

Outputs
Target Audience:During the current reporting period, we have presented to diverse audiences through classes and invited lectures, local and international symposia. Audiences were composed of graduate students, scientists, extension faculty in a range of fields encompassing agricultural sciences and fish biology through the following national and international venues. Information was disseminated through the conferences and symposia reported under "products" and through the following invited lectures: 1) Seale, A. P. (2019). New perspectives on osmoreception and osmoregulation in a euryhaline fish model. University of Arkansas seminar, Fayetteville, AK (Sep 19). 2) Seale, A. P. (2019). The osmotic control of prolactin release in a euryhaline fish model. North Carolina State University seminar, Raleigh, NC (May 30). Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?During the current reporting period, the project has provided opportunities for the training of 2 undergraduate students, 3 graduate students and 1 research specialist in a range of disciplines, ranging from tilapia broodstock and tank maintenance to experimental design, data analysis, presentation skills and sample collection. These skills provide first-hand experience with practices and techniques involved in aquaculture facilities and research. How have the results been disseminated to communities of interest?Results have been disseminated locally through invited lectures, national and international research symposia and through workshops. The presentations disseminated in these venues are listed under "Products" and "Target Audience". What do you plan to do during the next reporting period to accomplish the goals?We shall continue improvements on our research infrastructure and conduct the sampling of ongoing experiments, including histological analysis of experiments under Objective 3.

Impacts
What was accomplished under these goals? We presented data gathered from addressing Objectives 1 and 2 in a variety of venues listed under "Products", and published the results in the peer-reviewed journals Aquaculture, Environmental Toxicology and Journal of Comparative Physiology. Briefly, we conducted experiments which include studies on 1) the effects of growth hormone (GH) on the gene expression of nutrient transporters in the intestine of Mozambique tilapia (Oreochromis mossambicus); 2) effects of sex, salinity, and sampling period on pituitary growth hormone expression in Mozambique tilapia; and3) regulation of growth and reproductive genes by pituitary hormones in the liver, gonad, and muscle of male and female Mozambique tilapia. On the first experiment,our findings indicate that GH supports growth, at least in part, by stimulating the gene expression of its receptor and key nutrient transporters in the intestine. In the seconds study,we found that sex-specific patterns in gh expression is modulated by salinity regime and daylight period in Mozambique tilapia. In the third study, we aim to determine the effects of pituitary hormones on growth-related genes in the liver, gonad, and muscle of male and female Mozambique tilapia.The regulation of gonad development and growth promoting genes by both growth hormone and gonadotropins may form the basis of sexual dimorphism in tilapia. Further analyses of igf2 and igf binding proteins gene expression in liver gonad, and muscle will provide insight into the endocrine control of growth and the differences in size observed between male and female tilapia.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Barba, E., Conklin, E., Kraft, D., Seale, A.P., Toonen, R. 2019. AssessPool: a flexible pipeline for population genomic analyses of pooled sequencing data. A case study on salinity acclimation in tilapia. Joint Conference of the 12th International Marine Biotechnology Conference and the 12th Asia Pacific Marine Biotechnology Conference, Shizuoka, Japan.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Celino-Brady, F.T., Petro-Sakuma, C.K., Breves, J.P., Lerner, D.T., Seale, A.P.2019. Early Life exposure to 17?-estradiol and nonylphenol affects the gh/igf system and expression of estrogen receptors in Mozambique tilapia. 5th Biennial Conference of the North American Society for Comparative Endocrinology, Gainesville, FL (May 25-28).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Seale, A. P. 2019. A fish prolactin cell model to investigate the emerging integration between osmoreception, thermoreception and autocrine signaling. The Growth Hormone (GH)/ Prolactin (PRL) Family in Biology and Disease. Federation of American Societies for Experimental Biology (FASEB) Science Research Conferences, West Palm Beach, FL (July 7-12).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Seale, A.P. 2019. Acclimation of fish to dynamically changing salinities: insights from the euryhaline Mozambique tilapia. 5th Biennial Conference of the North American Society for Comparative Endocrinology, Gainsville, FL (May 25-28).
  • Type: Conference Papers and Presentations Status: Published Year Published: 2019 Citation: Petro-Sakuma, C.K., Celino-Brady, F.T., Seale, A.P. 2019. Regulation of Intestinal Nutrient Transporters by the pituitary gland in Mozambique Tilapia (Oreochromis mossambicus). College of Tropical Agriculture and Human Resources Student Research Symposium, University of Hawai?i, Honolulu, HI.
  • Type: Other Status: Published Year Published: 2019 Citation: Seale, A.P. and Ellis, S. 2019. Sustainable capture-based aquaculture of rabbitfish in Pacific Island Lagoons. College of Tropical Agriculture and Human Resource. Aquaculture and Aquaponics AA-1. ISBN 978-1-929054-15-2.
  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Seale, A.P., Pavlosky, K.K., Celino-Brady, F., Yamaguchi, Y., Breves, J.P., Lerner, D.T. 2019. Systemic versus tissue-level modulation of prolactin signaling in a euryhaline teleost subjected to tidally changing slainities. J. Comp. Physiol. doi: 10.1007/s00360-019-01233-9.
  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Celino-Brady, F., Petro-Sakuma, C.K., Breves, J.P., Lerner, D.T., Seale, A.P. 2019. Early-life exposure to 17?-estradiol and 4-nonylphenol impacts the growth hormone/insulin-like growth-factor system and estrogen receptors in Mozambique tilapia, Oreochromis mossambicus. J. Aqua. Tox. https://doi.org/10.1016/j.aquatox.2019.105336
  • Type: Journal Articles Status: Published Year Published: 2019 Citation: Seale, A.P., Pavlosky, K.K., Celino-Brady, F., Lerner, D.T. 2019. Sex, salinity and sampling period dependent patterns of growth hormone mRNA expression in Mozambique tilapia. Aquaculture. https://doi.org/10.1016/j.aquaculture.2019.734766
  • Type: Theses/Dissertations Status: Published Year Published: 2019 Citation: Petro-Sakuma, C., 2019. Effects of growth hormone and salinity on gene expression of nutrient transporters in the Intestine of Mozambique Tilapia (Oreochromis mossambicus). M.Sc. in Animal Sciences, University of Hawaii at M?noa, Honolulu, Hawaii.


Progress 10/01/17 to 09/30/18

Outputs
Target Audience:During the current reporting period we have presented at local aquaculture and Hawaiian fish pond practitioners and enthusiasts at Science Night at He'eia fish pond (Dec 7, 2017) In addition to reaching out to diverse audiences through classes and invited lectures, we also presented this work to audiences composed of graduate students, scientists, extension faculty in a range of fields encompassing agricultural sciences and fish biology through the following national and international venues: 1) 2018 CTAHR Student Research Symposium at the University of Hawaii at Manoa (Apr 6-7, 2018) 2) Sino-US Symposium on Food Nutrition and Health, Hainan University, Haikou, China (Jun 4-8, 2018) 3) 13th International Congress on the Biology of Fish, Calgary, Canada (Jul 16-19, 2018) Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?During the current reporting period, the project has provided opportunities for the training of 4 undergraduate students, 1 graduate student and 1 research specialist in a range of disciplines, ranging from tilapia broodstock and tank maintenance to experimental design, data analysis, presentation skills and sample collection. These skills provide first-hand experience with practices and techniques involved in aquaculture facilities and research. How have the results been disseminated to communities of interest?Results have been disseminated locally through invited lectures and research symposia internationally through workshops and symposia. These presentations are listed under "Products" and "Target Audience". What do you plan to do during the next reporting period to accomplish the goals?We shall conduct the sampling of the ongoing experiments and analyze a 24 hour time course of fish acclimated to tidally changing salinities by correlating body weight andvarious parameters of the GH-IGF axis, including pituitary GH mRNA expression.

Impacts
What was accomplished under these goals? We published part of the data gathered from addressing Objective 2 in the peer reviewed journal Comparative Physiology and Biochemistry. By analyzing the effectors of ion transport in gill and changes in the osmoregulatory hormone, prolactin, we demonstrated the ability of adult tilapia reared in steady-state salinities to successfully acclimate to dynamically-changing salinities. An experiment to address the effects of environmental stressors on tilapia juvenile was finalized and parameters of the GH-IGF axis are currently being analyzed and further experiments on employing salinity transfer and acclimation to tidally-changing salinities are currently underway.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Seale, A.P., Yamaguchi Y., Pavlosky, K.K., Lerner, D.T., and Grau, E.G. 2018. Endocrine control of ion balance in steady state versus dynamically changing salinity regimes in Mozambique tilapia. 13th International Congress on the Biology of Fish. Calgary, Canada.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Seale, A.P. 2018. Control of growth and osmoregulation in tilapia under dynamically-changing salinities. Sino-US Symposium on Food Nutrition and Health, Hainan University. Haikou, China.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Woo, D.W., Celino-Brady, F.T., Pavlosky, K.P., Lerner, D.T., and Seale, A.P. 2018. The effects of salinity on plasma glucose in Mozambique tilapia, Oreochromis mossambicus. Imi Wai Ola Student Science Conference. Honolulu, HI, USA.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Woo, D.W., Celino-Brady, F.T., Pavlosky, K.P., Lerner, D.T., and Seale, A.P. 2018. Stress response of Mozambique tilapia, Oreochromis mossambicus, subjected to cyclical changes in environmental salinity. 29th Annual CTAHR and COE student research symposium. Honolulu, HI, USA.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Petro-Sakuma, C.K., Celino-Brady, F.T., Lerner, D.T., and Seale A.P. 2018. Effects of waterborne exposure to nonylphenol on the growth and reproductive physiology of Mozambique Tilapia (Oreochromis mossambicus). 29th Annual CTAHR and COE student research symposium (April 8). Honolulu, HI, USA.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Head, T., Stoytcheva, Z., and Seale, A.P. 2018. In-silico analysis of Prolactin 177 and 188 promoters to identify mechanisms of osmoreception in Mozambique Tilapia (Oreochromis mossambicus). 29th Annual CTAHR and COE student research symposium. Honolulu, HI, USA.
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Pavlosky, K.K., Yamaguchi, Y., Lerner, D.T., and Seale, A.P. 2019. The effects of transfer from steady-state to tidally-changing salinities on plasma and branchial osmoregulatory parameters in adult Mozambique tilapia. Comp. Biochem. Physiol. 227, 134-145. doi: 10.1016/j.cbpa.2018.10.005.


Progress 08/05/17 to 09/30/17

Outputs
Target Audience:During the current reporting period we have presented at local UH Sea-Grant research symposium (Aug. 17, 2017), composed of graduate students, scientists and extension faculty in a range of fields encompassing coastal and ocean sciences. We have also presented at a University of Hawaii - University of Tokyo joint symposium (Sep 8th, 2017), composed of students and faculty from a range of coastal and ocean sciences from the US and Japan. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?During the current reporting period, the project has provided opportunities for the training of 1 undergraduate student, 1 graduate student and 1 research specialist in a range of disciplines, ranging from tilapia broodstock and tank maintenance to experimental design and sample collection. These skills provide first-hand experience with practices and techniques involved in aquaculture facilities and research. How have the results been disseminated to communities of interest?Results have disseminated in a research symposium and an international joint symposium between the University of Hawaii and University of Tokyo. These presentations are listed under "Products". What do you plan to do during the next reporting period to accomplish the goals?We shall conduct the sampling of the ongoing experiment on the effects of endocrine disruptors on parameters of growth and design a salinity challenge experiment. We plan to begin the determination of proposed endpoints once samples are collected.

Impacts
What was accomplished under these goals? An experiment to address the effects of environmental stressors on tilapia juvenile was setup. Specifically, tilapia juveniles were exposed for 21 days to the endocrine disrupting chemicals, nonylphenol and ethinyl estradiol. The experiment is currently underway. Revised protocols for the detection of mRNA expression of PRL and GH-IGF system genes for this and forthcoming experiments are under development in our new laboratory facilities at the Department of Human Nutrition Food and Animal Sciences, College of Tropical Agriculture and Human Resources, University of Hawaii.

Publications

  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Seale, A.P., Yamaguchi, Y., Inokuchi, M., Moorman, B., Lerner, D.T. and Grau, E.G. 2017. Endocroine Control of Growth and Osmoregulation in fish: a comparison between steady state and dynamically changing salinity regimes. University of Hawaii and University of Tokyo, Joint Symposium on Ocean, Coastal, and Atmospheric Sciences. Honolulu, Hawaii..
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Celino-Brady, F.T., Yamaguchi, S., Miura, C., Miura, T., Lerner, D.T., and Seale, A.P. 2017. Modulation of Reproductive and Growth Axes by Environmental Endocrine Disruptors.. University of Hawaii and University of Tokyo, Joint Symposium on Ocean, Coastal, and Atmospheric Sciences. Honolulu, Hawaii.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Seale, A.P., Celino-Brady, F.T. 2017. The Use of a Euryhaline Tilapia to Assess the Endocrine Disrupting Effects of Anthropogenic Chemicals on Growth and Osmoregulation of a Tropical Teleost Species Inhabiting Coastal Waters and Wetlands in Hawaii and the Tropics Hawaii. Sea Grant Research Symposium, Honolulu, Hawaii.