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8. Transcriptomic and Epigenomic Responses to Cortisol-Mediated Stress in Rainbow Trout (Oncorhynchus mykiss) Skeletal Muscle.

Author

Aravena-Canales, Daniela, Valenzuela-Muñoz, Valentina, Gallardo-Escarate, Cristian, Molina, Alfredo, and Valdés, Juan Antonio

Subjects
RAINBOW trout, SKELETAL muscle, EPIGENOMICS, WHOLE genome sequencing, FOCAL adhesions, TRANSCRIPTOMES, CYTOSKELETON, MUSCLE growth
Abstract

The production and release of cortisol during stress responses are key regulators of growth in teleosts. Understanding the molecular responses to cortisol is crucial for the sustainable farming of rainbow trout (Oncorhynchus mykiss) and other salmonid species. While several studies have explored the genomic and non-genomic impacts of cortisol on fish growth and skeletal muscle development, the long-term effects driven by epigenetic mechanisms, such as cortisol-induced DNA methylation, remain unexplored. In this study, we analyzed the transcriptome and genome-wide DNA methylation in the skeletal muscle of rainbow trout seven days after cortisol administration. We identified 550 differentially expressed genes (DEGs) by RNA-seq and 9059 differentially methylated genes (DMGs) via whole-genome bisulfite sequencing (WGBS) analysis. KEGG enrichment analysis showed that cortisol modulates the differential expression of genes associated with nucleotide metabolism, ECM-receptor interaction, and the regulation of actin cytoskeleton pathways. Similarly, cortisol induced the differential methylation of genes associated with focal adhesion, adrenergic signaling in cardiomyocytes, and Wnt signaling. Through integrative analyses, we determined that 126 genes showed a negative correlation between up-regulated expression and down-regulated methylation. KEGG enrichment analysis of these genes indicated participation in ECM-receptor interaction, regulation of actin cytoskeleton, and focal adhesion. Using RT-qPCR, we confirmed the differential expression of lamb3, itga6, limk2, itgb4, capn2, and thbs1. This study revealed for the first time the molecular responses of skeletal muscle to cortisol at the transcriptomic and whole-genome DNA methylation levels in rainbow trout. [ABSTRACT FROM AUTHOR]

Published
2024
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17. High-Temperature Stress Induces Autophagy in Rainbow Trout Skeletal Muscle.

Author

Molina, Alfredo, Dettleff, Phillip, Valenzuela-Muñoz, Valentina, Gallardo-Escarate, Cristian, and Valdés, Juan Antonio

Subjects
RAINBOW trout, AMINO acid transport, SKELETAL muscle, AUTOPHAGY, COLD-blooded animals, MUSCLE contraction, WESTERN immunoblotting
Abstract

Ectothermic animals, such as teleosts, have increasingly been exposed to stressful high-temperature events due to global warming. Currently, the effects of thermal stress on skeletal muscle, a key tissue for fish growth, are unknown. This study examined the impact of high-temperature stress on the skeletal muscle transcriptome of rainbow trout (Oncorhynchus mykiss) in control (15 °C) and high-temperature (20 °C) conditions. Additionally, we examined the plasmatic levels of cortisol, glucose, and creatine kinase activity, and examined oxidative damage and autophagy activation in skeletal muscle. High-temperature stress induced significant increases in cortisol and glucose plasmatic levels. Nevertheless, no changes were observed in creatine kinase activity in plasma and skeletal muscle oxidation. Skeletal muscle RNA was isolated and sequenced using the HiSeq Illumina platform. A total of 383,796,290 reads were mapped onto the reference rainbow trout genome. The transcriptomic analysis showed that 293 genes were upregulated in the high-temperature group, mainly associated with autophagosome assembly, amino acid transport, and the glutamine metabolic process. On the other hand, 119 genes were downregulated in the high-temperature group, mainly associated with digestion, proteolysis, and the muscle contraction process. In addition, RT-qPCR of differentially expressed representative genes and Western blot analysis of LC3-II/LC3-I levels confirmed skeletal muscle autophagy induced by high temperature. This study sheds light on intriguing facets of the adaptive response of rainbow trout skeletal muscle to high-temperature stress and provides significant insights into the physiology of autophagy in teleosts. [ABSTRACT FROM AUTHOR]

Published
2023
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28. Differential Metabolic and Transcriptional Responses of Gilthead Seabream (Sparus aurata) Administered with Cortisol or Cortisol-BSA

Author

Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Fondo de Financiamiento de Centros de Investigación en Áreas Prioritarias (Chile), Fondo Nacional de Desarrollo Científico y Tecnológico (Chile), Ministerio de Economía y Competitividad (España), Aedo, Jorge E., Aravena-Canales, Daniela, Ruiz-Jarabo, Ignacio, Oyarzún, Ricardo, Molina, Alfredo, Martínez-Rodríguez, Gonzalo, Valdés, Juan Antonio, Mancera, Juan Miguel, Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Fondo de Financiamiento de Centros de Investigación en Áreas Prioritarias (Chile), Fondo Nacional de Desarrollo Científico y Tecnológico (Chile), Ministerio de Economía y Competitividad (España), Aedo, Jorge E., Aravena-Canales, Daniela, Ruiz-Jarabo, Ignacio, Oyarzún, Ricardo, Molina, Alfredo, Martínez-Rodríguez, Gonzalo, Valdés, Juan Antonio, and Mancera, Juan Miguel

Abstract

Cortisol is the main glucocorticoid hormone promoting compensatory metabolic responses of stress in teleosts. This hormone acts through genomic and membrane-initiated actions to exert its functions inside the cell. Experimental approaches, using exogenous cortisol administration, confirm the role of this hormone during short (minutes to hours)- and long-term (days to weeks) responses to stress. The role of membrane-initiated cortisol signaling during long-term responses has been recently explored. In this study, Sparus aurata were intraperitoneally injected with coconut oil alone or coconut oil containing cortisol, cortisol-BSA, or BSA. After 3 days of treatment, plasma, liver, and skeletal muscle were extracted. Plasma cortisol, as well as metabolic indicators in the plasma and tissues collected, and metabolism-related gene expression, were measured. Our results showed that artificially increased plasma cortisol levels in S. aurata enhanced plasma glucose and triacylglycerols values as well as hepatic substrate energy mobilization. Additionally, cortisol stimulated hepatic carbohydrates metabolism, as seen by the increased expression of metabolism-related genes. All of these responses, observed in cortisol-administered fish, were not detected by replicating the same protocol and instead using cortisol-BSA, which exclusively induces membrane-initiated effects. Therefore, we suggest that after three days of cortisol administration, only genomic actions are involved in the metabolic responses in S. aurata.

Published
2021

31. Labelling fish diets with 15N ‐Leucine for monitoring feed consumption and bio‐distribution in Atlantic salmon.

Author

Cortés‐Quezada, Mirta, Parada, Ana María, Videla, Ximena, Valdés, Juan Antonio, Gonzalez‐Catrilelbún, Sebastián, Aspée, Alexis, Nario, Adriana, and Rivas‐Aravena, Andrea

Subjects
ATLANTIC salmon, FISH weight, NITROGEN isotopes, FISH as food, FISH feeds, FOOD consumption, SALMON farming
Abstract

Feeding represents 50–70% of the cost of production in salmon farming, higher than any other animal farm. The improvement of this percentage is challenging as the food is thrown into the fish tank, there is no quantification of the amount of food that is consumed by the fish. In consequence, it is difficult to adjust the food composition making it more nutritive or promoting food consumption by fish. In this study, to investigate food consumption, bio‐distribution and food residues, leucine containing 15N (a stable isotope of nitrogen) was used to label the fish food. Atlantic salmon (Salmo salar) weighing 100–120 g were maintained in 30 L tanks at a density of 14 kg/m3. Fishes were fed daily at 1% of the fish weight with pellet labelled with 15N‐leucine. The 15N incorporation was determined 14 hours after the feeding in all the fish organs. Results showed that 14 hours after the administration of a single dose of labelled food to Atlantic salmon enables the detection of the tracer in the whole organism allowing determining the food consumption. Through the analysis of nitrogen use efficiency (NUE), we showed that the trunk, pyloric caeca and head incorporate the highest level of the marker (72.7, 8.7 and 5.7%, respectively). This methodology would permit monitoring feeding to minimize food loss, improve administration methodologies or select the preferred foods for the fish, among others to reduce production costs. [ABSTRACT FROM AUTHOR]

Published
2022
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36. Fishing a hypothetical membrane receptor in the gilthead sea bream (Sparus aurata): role in acute stress

Author

Ministerio de Economía y Competitividad (España), Aedo, Jorge E., Ruiz-Jarabo, Ignacio, Martínez-Rodríguez, Gonzalo, Boltaña, Sebastián, Molina, Alfredo, Valdés, Juan Antonio, Mancera, Juan Miguel, Ministerio de Economía y Competitividad (España), Aedo, Jorge E., Ruiz-Jarabo, Ignacio, Martínez-Rodríguez, Gonzalo, Boltaña, Sebastián, Molina, Alfredo, Valdés, Juan Antonio, and Mancera, Juan Miguel

Abstract

Cortisol is the most important hormone involved in the regulation of neuroendocrine stress response in teleosts. Effects of this hormone are mediated through its intracellular receptors, although membrane components are also involved, with unclear roles during the stress response. In this work, the contribution of membrane-initiated cortisol actions on stress-related parameters and metabolism-related genes in gilthead sea bream (Sparus aurata) were evaluated. Two in vivo experiments were performed. In the first, fish were administered with vehicle, BSA, cortisol and cortisol-BSA (membrane impermeable analogue) dissolved in saline (PBS 1X). In the second, the same treatments were replicated but using coconut oil as a vehicle. Fish were sampled after one and six hours (first experiment) and after three days (second experiment). Plasma cortisol, glucose and lactate levels were measured, and hepatic transcript levels of key genes involved in glucose metabolism, like glucose-6-phosphatase (g6pc), phosphoglycerate mutase 1 (pgam1), among others, were also analyzed. Fish implanted with each version of cortisol in both in vivo experiments reached plasma levels typically observed under an acute stress in S. aurata. Cortisol and cortisol-BSA increased glucose and lactate plasma levels after six hours of treatment. However, cortisol, but not cortisol-BSA, maintained increased plasma glucose levels after three days of treatment. Analysis by qPCR showed that expression of g6pc increased after one hour of cortisol and cortisol-BSA administration. However, cortisol, but not cortisol-BSA, maintained the g6pc up-regulation after three days. Our results suggested that membrane-initiated cortisol actions contributed to the regulation of early metabolic adaptations in S. aurata submitted to an emulated acute stress situation.

Published
2019

37. Contribution of non-canonical cortisol actions in the early modulation of glucose metabolism of gilthead sea bream (Sparus aurata)

Author

Ministerio de Economía y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Aedo, Jorge E., Ruiz-Jarabo, Ignacio, Martínez-Rodríguez, Gonzalo, Boltaña, Sebastián, Molina, Alfredo, Valdés, Juan Antonio, Mancera, Juan Miguel, Ministerio de Economía y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), Agencia Estatal de Investigación (España), Aedo, Jorge E., Ruiz-Jarabo, Ignacio, Martínez-Rodríguez, Gonzalo, Boltaña, Sebastián, Molina, Alfredo, Valdés, Juan Antonio, and Mancera, Juan Miguel

Abstract

Teleost fish are exposed to diverse stressors in farming and wildlife conditions during their lifespan. Cortisol is the main glucocorticoid hormone involved in the regulation of their metabolic acclimation under physiological stressful conditions. In this context, increased plasma cortisol is associated with energy substrate mobilization from metabolic tissues, such as liver and skeletal muscle, to rapidly obtain energy and cope with stress. The metabolic actions of cortisol have primarily been attributed to its genomic/classic action mechanism involving the interaction with intracellular receptors, and regulation of stress-responsive genes. However, cortisol can also interact with membrane components to activate rapid signaling pathways. In this work, using the teleost fish gilthead sea bream (Sparus aurata) as a model, we evaluated the effects of membrane-initiated cortisol actions on the early modulation of glucose metabolism. For this purpose, S. aurata juveniles were intraperitoneally administrated with cortisol and with its membrane impermeable analog, cortisol-BSA. After 1 and 6 h of each treatment, plasma cortisol levels were measured, together with glucose, glycogen and lactate in plasma, liver and skeletal muscle. Transcript levels of corticosteroids receptors (gr1, gr2, and mr) and key gluconeogenesis (g6pc and pepck)- and glycolysis (pgam1 and aldo) related genes in the liver were also measured. Cortisol and cortisol-BSA administration increased plasma cortisol levels in S. aurata 1 h after administration. Plasma glucose levels enhanced 6 h after each treatment. Hepatic glycogen content decreased in the liver at 1 h of both cortisol and cortisol-BSA administration, while increased at 6 h due to cortisol but not in response to cortisol-BSA. Expression of gr1, g6pc, pgam1, and aldo were preferentially increased by cortisol-BSA in the liver. Taking all these results in consideration, we suggest that non-canonical cortisol mechanisms contribute to the regula

Published
2019

48. Transcriptomic analysis of the hepatic response to stress in the red cusk-eel (Genypterus chilensis): Insights into lipid metabolism, oxidative stress and liver steatosis

Author

Naour, Sebastian, primary, Espinoza, Brisa M., additional, Aedo, Jorge E., additional, Zuloaga, Rodrigo, additional, Maldonado, Jonathan, additional, Bastias-Molina, Macarena, additional, Silva, Herman, additional, Meneses, Claudio, additional, Gallardo-Escarate, Cristian, additional, Molina, Alfredo, additional, and Valdés, Juan Antonio, additional

Published
2017
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50. Corrigendum to “Nutritional status modulates plasma leptin, AMPK and TOR activation, and mitochondrial biogenesis: Implications for cell metabolism and growth in skeletal muscle of the fine flounder” [Gen. Comp. Endocr. 186 (2013) 172–180]

Author

Fuentes, Eduardo N., primary, Safian, Diego, additional, Einarsdottir, Ingibjörg Eir, additional, Valdés, Juan Antonio, additional, Elorza, Alvaro A., additional, Molina, Alfredo, additional, and Björnsson, Björn Thrandur, additional

Published
2015
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