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Comesaña S, Antomagesh F, Soengas JL, Blanco AM, Vijayan MM. Valine administration in the hypothalamus alters the brain and plasma metabolome in rainbow trout. Am J Physiol Regul Integr Comp Physiol 2024; 327:R261-R273. [PMID: 38881412 DOI: 10.1152/ajpregu.00056.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2024] [Revised: 05/28/2024] [Accepted: 06/06/2024] [Indexed: 06/18/2024]
Abstract
Central administration of valine has been shown to cause hyperphagia in fish. Although mechanistic target of rapamycin (mTOR) is involved in this response, the contributions to feed intake of central and peripheral metabolite changes due to excess valine are unknown. Here, we investigated whether intracerebroventricular injection of valine modulates central and peripheral metabolite profiles and may provide insights into feeding response in fish. Juvenile rainbow trout (Oncorhynchus mykiss) were administered an intracerebroventricular injection of valine (10 µg·µL-1 at 1 μL·100·g-1 body wt), and the metabolite profile in plasma, hypothalamus, and rest of the brain (composing of telencephalon, optic tectum, cerebellum, and medulla oblongata) was carried out by liquid chromatography-mass spectrometry (LC/MS)-based metabolomics. Valine administration led to a spatially distinct metabolite profile at 1 h postinjection in the brain: enrichment of amino acid metabolism and energy production pathways in the rest of the brain but not in hypothalamus. This suggests a role for extrahypothalamic input in the regulation of feed intake. Also, there was enrichment of several amino acids, including tyrosine, proline, valine, phenylalanine, and methionine, in plasma in response to valine. Changes in liver transcript abundance and protein expression reflect an increased metabolic capacity, including energy production from glucose and fatty acids, and a lower protein kinase B (Akt) phosphorylation in the valine group. Altogether, valine intracerebroventricular administration affects central and peripheral metabolism in rainbow trout, and we propose a role for the altered metabolite profile in modulating the feeding response to this branched-chain amino acid.NEW & NOTEWORTHY Valine causes hyperphagia in fish when it is centrally administered; however, the exact mechanisms are far from clear. We tested how intracerebroventricular injection of valine in rainbow trout affected the brain and plasma metabolome. The metabolite changes in response to valine were more evident in the rest of the brain compared with the hypothalamus. Furthermore, we demonstrated for the first time that central valine administration affects peripheral metabolism in rainbow trout.
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Affiliation(s)
- Sara Comesaña
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo, Spain
| | | | - José L Soengas
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo, Spain
| | - Ayelén M Blanco
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo, Spain
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Blanco AM, Antomagesh F, Comesaña S, Soengas JL, Vijayan MM. Chronic cortisol stimulation enhances hypothalamus-specific enrichment of metabolites in the rainbow trout brain. Am J Physiol Endocrinol Metab 2024; 326:E382-E397. [PMID: 38294699 DOI: 10.1152/ajpendo.00410.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 01/08/2024] [Accepted: 01/24/2024] [Indexed: 02/01/2024]
Abstract
The hypothalamus is a key integrating center that is involved in the initiation of the corticosteroid stress response, and in regulating nutrient homeostasis. Although cortisol, the principal glucocorticoid in humans and teleosts, plays a central role in feeding regulation, the mechanisms are far from clear. We tested the hypothesis that the metabolic changes to cortisol exposure signal an energy excess in the hypothalamus, leading to feeding suppression during stress in fish. Rainbow trout (Oncorhynchus mykiss) were administered a slow-release cortisol implant for 3 days, and the metabolite profiles in the plasma, hypothalamus, and the rest of the brain were assessed. Also, U-13C-glucose was injected into the hypothalamus by intracerebroventricular (ICV) route, and the metabolic fate of this energy substrate was followed in the brain regions by metabolomics. Chronic cortisol treatment reduced feed intake, and this corresponded with a downregulation of the orexigenic gene agrp, and an upregulation of the anorexigenic gene cart in the hypothalamus. The U-13C-glucose-mediated metabolite profiling indicated an enhancement of glycolytic flux and tricarboxylic acid intermediates in the rest of the brain compared with the hypothalamus. There was no effect of cortisol treatment on the phosphorylation status of AMPK or mechanistic target of rapamycin in the brain, whereas several endogenous metabolites, including leucine, citrate, and lactate were enriched in the hypothalamus, suggesting a tissue-specific metabolic shift in response to cortisol stimulation. Altogether, our results suggest that the hypothalamus-specific enrichment of leucine and the metabolic fate of this amino acid, including the generation of lipid intermediates, contribute to cortisol-mediated feeding suppression in fish.NEW & NOTEWORTHY Elevated cortisol levels during stress suppress feed intake in animals. We tested whether the feed suppression is associated with cortisol-mediated alteration in hypothalamus metabolism. The brain metabolome revealed a hypothalamus-specific metabolite profile suggesting nutrient excess. Specifically, we noted the enrichment of leucine and citrate in the hypothalamus, and the upregulation of pathways involved in leucine metabolism and fatty acid synthesis. This cortisol-mediated energy substrate repartitioning may modulate the feeding/satiety centers leading to the feeding suppression.
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Affiliation(s)
- Ayelén M Blanco
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo, Spain
| | | | - Sara Comesaña
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo, Spain
| | - José L Soengas
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo, Spain
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Favalier N, Roy J, Dias K, Maunas P, Turonnet N, Conde-Sieira M, Panserat S, Soengas JL, Marandel L. Sex dimorphism of glucosensing parameters and appetite-regulating peptides in the hypothalamus of rainbow trout broodstocks. Comp Biochem Physiol A Mol Integr Physiol 2023; 281:111436. [PMID: 37085140 DOI: 10.1016/j.cbpa.2023.111436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 04/03/2023] [Accepted: 04/17/2023] [Indexed: 04/23/2023]
Abstract
Rainbow trout (Oncorhynchus mykiss) is traditionally considered as a poor user of digestible carbohydrates harbouring persistent postprandial hyperglycaemia and decreased growth performances when fed a diet containing more than 20% of digestible carbohydrates. While this glucose-intolerant phenotype is well-described in juveniles, evidence points to a particular regulation of glucose metabolism in rainbow trout broodstrocks. By detecting changes in glucose levels and triggering a specific metabolic response, the hypothalamus plays a key role in the regulation of peripheral glucose metabolism. Therefore, our objective was to assess, for the first time in fish, the short-term consequences in hypothalamus, the glucose sensing and feed intake regulation of feeding mature female and male, and neomale rainbow trout with a diet containing either no or a 33% carbohydrate. The hypothalamic glucosensing capacity was assessed through mRNA levels of glucosensing related-genes and feed intake regulation through appetite-regulating peptides. Our data indicate that a brief period of carbohydrate intake (5 meals at 8 °C) did not induce specific changes in glucosensing capacity and appetite-regulating peptides in the hypothalamus of rainbow trout broodstock. Our results did however demonstrate, for the first time in fish, the existence of sex dimorphism of glucosensing-related genes and appetite-regulating peptides.
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Affiliation(s)
- Nathan Favalier
- INRAE, Université de Pau et des Pays de l'Adour, e2s, St-Pee-sur-Nivelle, France
| | - Jérôme Roy
- INRAE, Université de Pau et des Pays de l'Adour, e2s, St-Pee-sur-Nivelle, France
| | - Karine Dias
- INRAE, Université de Pau et des Pays de l'Adour, e2s, St-Pee-sur-Nivelle, France
| | - Patrick Maunas
- INRAE, Université de Pau et des Pays de l'Adour, e2s, St-Pee-sur-Nivelle, France
| | - Nicolas Turonnet
- INRAE, Université de Pau et des Pays de l'Adour, e2s, St-Pee-sur-Nivelle, France
| | - Marta Conde-Sieira
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, E-36310 Vigo, Spain
| | - Stephane Panserat
- INRAE, Université de Pau et des Pays de l'Adour, e2s, St-Pee-sur-Nivelle, France
| | - José Luis Soengas
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, E-36310 Vigo, Spain
| | - Lucie Marandel
- INRAE, Université de Pau et des Pays de l'Adour, e2s, St-Pee-sur-Nivelle, France.
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Shen HC, Chen ZQ, Liu XC, Guan JF, Xie DZ, Li YY, Xu C. Sodium oxamate reduces lactate production to improve the glucose homeostasis of Micropterus salmoides fed high-carbohydrate diets. Am J Physiol Regul Integr Comp Physiol 2023; 324:R227-R241. [PMID: 36572554 DOI: 10.1152/ajpregu.00226.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The study was performed to evaluate the effects of the reduced lactate production by sodium oxamate (SO) on growth performance, lactate and glucose and lipid metabolism, and glucose tolerance of Micropterus salmoides fed high-carbohydrate (CHO) diets. In in vitro study, primary hepatocytes were incubated for 48 h in a control medium (5.5 mM glucose), a high-glucose medium (25 mM glucose, HG), or a SO-containing high-glucose medium (25 mM glucose + 50 mM SO, HG-SO). Results indicated lactate and triglyceride (TG) levels, and lactate dehydrogenase a (LDH-a) expression in the HG-SO group were remarkably lower than those of the HG group. In in vivo study, M. salmoides (5.23 ± 0.03 g) were fed four diets containing a control diet (10% CHO, C) and three SO contents [0 (HC), 100 (HC-SO1), and 200 (HC-SO2) mg·kg-1, respectively] of high-CHO diets (20% CHO) for 11 wk. High-CHO diets significantly reduced weight gain rate (WGR), specific growth rate (SGR), p-AMPK-to-t-AMPK ratio, and expression of insulin receptor substrate 1 (IRS1), insulin-like growth factor I (IGF-I), insulin-like growth factor I receptor (IGF-IR), fructose-1,6-biphosphatase (FBPase), peroxisome proliferator-activated receptor α (PPARα), and carnitine palmitoyl transferase 1α (CPT1α) compared with the C group, whereas the opposite was true for plasma levels of glucose, TG, lactate, tissue glycogen, and lipid contents, and expression of LDH-a, monocarboxylate transporter 1 and 4 (MCT1 and MCT4), insulin, glucokinase (GK), pyruvate dehydrogenase E1 subunit (PDH), sterol-regulatory element-binding protein 1 (SREBP1), fatty acid synthase (FAS). The HC-SO2 diets remarkably increased WGR, SGR, p-AMPK-to-t-AMPK ratio, and expression of IRS1, IGF-I, IGF-IR, GK, PDHα, PDHβ, FAS, acetyl-CoA carboxylase 1 (ACC1), PPARα, and CPT1α compared with the HC group. Besides, HC-SO2 diets also enhanced glucose tolerance of fish after a glucose loading. Overall, the reduced lactate production by SO benefits growth performance and glucose homeostasis of high-CHO-fed M. salmoides through the enhancement of glycolysis, lipogenesis, and fatty acid β-oxidation coupled with the suppression of glycogenesis and gluconeogenesis.
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Affiliation(s)
- Hui-Chao Shen
- College of Marine Sciences, South China Agricultural University, Guangzhou, China.,University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, Guangzhou, China
| | - Zhi-Qiang Chen
- College of Marine Sciences, South China Agricultural University, Guangzhou, China
| | - Xiao-Cheng Liu
- College of Marine Sciences, South China Agricultural University, Guangzhou, China
| | - Jun-Feng Guan
- College of Marine Sciences, South China Agricultural University, Guangzhou, China.,University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, Guangzhou, China
| | - Di-Zhi Xie
- College of Marine Sciences, South China Agricultural University, Guangzhou, China.,University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, Guangzhou, China
| | - Yuan-You Li
- College of Marine Sciences, South China Agricultural University, Guangzhou, China.,University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, Guangzhou, China
| | - Chao Xu
- College of Marine Sciences, South China Agricultural University, Guangzhou, China.,University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, Guangzhou, China
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Chivite M, Comesaña S, Calo J, Soengas JL, Conde-Sieira M. Endocannabinoid receptors are involved in enhancing food intake in rainbow trout. Horm Behav 2022; 146:105277. [PMID: 36356457 DOI: 10.1016/j.yhbeh.2022.105277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 10/17/2022] [Accepted: 10/21/2022] [Indexed: 11/11/2022]
Abstract
The mechanisms involved in hedonic regulation of food intake, including endocannabinoid system (ECs) are scarcely known in fish. We recently demonstrate in rainbow trout the presence of a rewarding response mediated by ECs in hypothalamus and telencephalon when fish fed a lipid-enriched diet, and that central administration of main agonists of ECs namely AEA or 2-AG exert a bimodal effect on feed intake in fish with low doses inducing an increase that disappears with the high dose of both endocannabinoids (EC). To assess the precise involvement of the different receptors of the ECs (CNR1, TRPV1, and GPR55) in this response we injected intracerebroventricularly AEA or 2-AG in the absence/presence of specific receptor antagonists (AM251, capsazepine, and ML193; respectively). The presence of antagonists clearly counteracts the effect of EC supporting the specificity of EC action inducing changes not only in ECs but also in GABA and glutamate metabolism ultimately leading to the increase observed in food intake response.
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Affiliation(s)
- Mauro Chivite
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain
| | - Sara Comesaña
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain
| | - Jessica Calo
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain
| | - José L Soengas
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain
| | - Marta Conde-Sieira
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain.
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Comesaña S, Chivite M, Blanco AM, Alborja-Valado M, Calo J, Conde-Sieira M, Soengas JL. Involvement of Mechanistic Target of Rapamycin (mTOR) in Valine Orexigenic Effects in Rainbow Trout. AQUACULTURE NUTRITION 2022; 2022:7509382. [PMID: 36860456 PMCID: PMC9973124 DOI: 10.1155/2022/7509382] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/06/2022] [Accepted: 09/14/2022] [Indexed: 06/18/2023]
Abstract
This study was aimed at clarifying the importance of a mechanistic target of rapamycin (mTOR) in the central orexigenic effect of valine in fish. For this, rainbow trout (Oncorhynchus mykiss) were intracerebroventricularly (ICV) injected with valine alone or in the presence of rapamycin as the mTOR inhibitor, and two experiments were performed. In the first experiment, we evaluated feed intake levels. In the second experiment, we evaluated in the hypothalamus and telencephalon the following: (1) the phosphorylation status of mTOR and its downstream effectors ribosomal protein S6 and p70 S6 kinase 1 (S6K1), (2) the abundance and phosphorylation status of transcription factors involved in appetite regulation, and (3) the mRNA levels of key neuropeptides associated with homeostatic regulation of feed intake in fish. Rising central levels of valine clearly resulted in an orexigenic response in rainbow trout. This response occurred in parallel with mTOR activation in both the hypothalamus and telencephalon, as supported by depressant changes in proteins involved in mTOR signalling (S6 and S6K1). Also, these changes disappeared in the presence of rapamycin. However, it is not clear which precise mechanisms link the activation of mTOR and the alteration in feed intake levels since we did not observe changes in mRNA levels of appetite-regulatory neuropeptides as well as in the phosphorylation status and levels of integrative proteins.
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Affiliation(s)
- Sara Comesaña
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, E-36310 Vigo, Spain
| | - Mauro Chivite
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, E-36310 Vigo, Spain
| | - Ayelén M. Blanco
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, E-36310 Vigo, Spain
| | - María Alborja-Valado
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, E-36310 Vigo, Spain
| | - Jessica Calo
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, E-36310 Vigo, Spain
| | - Marta Conde-Sieira
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, E-36310 Vigo, Spain
| | - José L. Soengas
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, E-36310 Vigo, Spain
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Díaz-Rúa A, Chivite M, Comesaña S, Velasco C, Soengas JL, Conde-Sieira M. Central administration of endocannabinoids exerts bimodal effects in food intake of rainbow trout. Horm Behav 2021; 134:105021. [PMID: 34242873 DOI: 10.1016/j.yhbeh.2021.105021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 05/28/2021] [Accepted: 06/22/2021] [Indexed: 10/20/2022]
Abstract
The endocannabinoid system (ECs) is known to participate in several processes in mammals related to synaptic signaling including regulation of food intake, appetite and energy balance. In fish, the relationship of ECs with food intake regulation is poorly understood. In the present study, we assessed in rainbow trout Oncorhynchus mykiss the effect of intracerebroventricular administration (ICV) of low and high doses of the endocannabinoids anandamide (AEA) and 2-arachidonoylglycerol (2-AG) on food intake. We assessed endocannabinoid levels in hypothalamus, telencephalon and plasma as well as the effect of AEA and 2-AG administration at central level on gene expression of receptors involved in ECs (cnr1, gpr55 and trpv1) and markers of neural activity (fos, ntrk2 and GABA-related genes). The results obtained indicate that whereas high doses of endocannabinoids did not elicit changes in food intake levels, low doses of the endocannabinoids produce an orexigenic effect that could be due to a possible inhibition of gabaergic neurotransmission and the modulation of neural plasticity in brain areas related to appetite control, such as hypothalamus and telencephalon.
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Affiliation(s)
- Adrián Díaz-Rúa
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain
| | - Mauro Chivite
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain
| | - Sara Comesaña
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain
| | - Cristina Velasco
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain; CIIMAR, Centro Interdisciplinar de Investigação Marinha e Ambiental, Universidade do Porto, Terminal de Cruzeiros do Porto de Leixões, Av.General Norton de Matos, S/N, 4450-208 Matosinhos, Portugal
| | - José L Soengas
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain
| | - Marta Conde-Sieira
- Centro de Investigación Mariña, Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain.
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Falco F, Barra M, Wu G, Dioguardi M, Stincone P, Cuttitta A, Torri M, Bonanno A, Cammarata M. Engraulis encrasicolus larvae from two different environmental spawning areas of the Central Mediterranean Sea: first data on amino acid profiles and biochemical evaluations. EUROPEAN ZOOLOGICAL JOURNAL 2020. [DOI: 10.1080/24750263.2020.1823493] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- F. Falco
- Marine Biological and Biotechnological Resources Institute (IRBIM), National Research Council (CNR), Italy
| | - M. Barra
- Institute for the Study of Anthropic Impacts and Sustainability in the Marine Environment (IAS), Units of Capo Granitola (TP) and Naples, Italy
| | - G. Wu
- Department of Animal Science, Texas A&M University, TX, USA
| | - M. Dioguardi
- Department of Earth and Marine Sciences, University of Palermo, Italy
| | - P. Stincone
- Laboratório de Bioquímica e Microbiologia Aplicada, Instituto de Ciência e Tecnologia de Alimentos, Universidade Federal do Rio Grande do Sul, Brazil
| | - A. Cuttitta
- Institute for the Study of Anthropic Impacts and Sustainability in the Marine Environment (IAS), Units of Capo Granitola (TP) and Naples, Italy
| | - M. Torri
- Institute for the Study of Anthropic Impacts and Sustainability in the Marine Environment (IAS), Units of Capo Granitola (TP) and Naples, Italy
| | - A. Bonanno
- Institute for the Study of Anthropic Impacts and Sustainability in the Marine Environment (IAS), Units of Capo Granitola (TP) and Naples, Italy
| | - M. Cammarata
- Department of Earth and Marine Sciences, University of Palermo, Italy
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Velasco C, Conde-Sieira M, Comesaña S, Chivite M, Díaz-Rúa A, Míguez JM, Soengas JL. The long-chain fatty acid receptors FFA1 and FFA4 are involved in food intake regulation in fish brain. J Exp Biol 2020; 223:jeb227330. [PMID: 32665445 DOI: 10.1242/jeb.227330] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 07/08/2020] [Indexed: 12/13/2022]
Abstract
We hypothesized that the free fatty acid receptors FFA1 and FFA4 might be involved in the anorectic response observed in fish after rising levels of long-chain fatty acids (LCFAs) such as oleate. In one experiment we demonstrated that intracerebroventricular (i.c.v.) treatment of rainbow trout with FFA1 and FFA4 agonists elicited an anorectic response 2, 6 and 24 h after treatment. In a second experiment, the same i.c.v. treatment resulted after 2 h in an enhancement in the mRNA abundance of anorexigenic neuropeptides pomca1 and cartpt and a decrease in the values of orexigenic peptides npy and agrp1 These changes occurred in parallel with those observed in the mRNA abundance and/or protein levels of the transcription factors Creb, Bsx and FoxO1, protein levels and phosphorylation status of Ampkα and Akt, and mRNA abundance of plcb1 and itrp3 Finally, we assessed in a third experiment the response of all these parameters after 2 h of i.c.v. treatment with oleate (the endogenous ligand of both free fatty acid receptors) alone or in the presence of FFA1 and FFA4 antagonists. Most effects of oleate disappeared in the presence of FFA1 and FFA4 antagonists. The evidence obtained supports the involvement of FFA1 and FFA4 in fatty acid sensing in fish brain, and thus involvement in food intake regulation through mechanisms not exactly comparable (differential response of neuropeptides and cellular signalling) to those known in mammals.
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Affiliation(s)
- Cristina Velasco
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, 36310 Vigo, Spain
| | - Marta Conde-Sieira
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, 36310 Vigo, Spain
| | - Sara Comesaña
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, 36310 Vigo, Spain
| | - Mauro Chivite
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, 36310 Vigo, Spain
| | - Adrián Díaz-Rúa
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, 36310 Vigo, Spain
| | - Jesús M Míguez
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, 36310 Vigo, Spain
| | - José L Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, 36310 Vigo, Spain
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10
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Chang CH, Zhou XW, Wang YC, Lee TH. Differential effects of hypothermal stress on lactate metabolism in fresh water- and seawater-acclimated milkfish, Chanos chanos. Comp Biochem Physiol A Mol Integr Physiol 2020; 248:110744. [PMID: 32569829 DOI: 10.1016/j.cbpa.2020.110744] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 06/01/2020] [Accepted: 06/08/2020] [Indexed: 10/24/2022]
Abstract
The milkfish Chanos chanos, an economically important cultured marine species in Southeast Asia, exhibits stenothermal and euryhaline characteristics and huge mortality usually occurs during extreme cold weather in winter. Under conditions beyond optimal temperatures, ectothermic species experience an increase in anaerobic glycolysis. To better understand the hypothermal acclimation response of this tropical species, the lactate metabolic profiles of freshwater (FW)- and seawater (SW)-acclimated milkfish were compared under control (optimal temperature; 28 °C) and hypothermal treatment (18 °C) conditions. In this study, the lactate dehydrogenase (LDH) isoform genes, ldha and ldhb, were identified in milkfish livers and muscles, respectively. The LDH is a bidirectional enzyme that triggered the conversion of pyruvate to lactate via anaerobic glycolysis as LDH exhibits the reductase activity (LDH-R), while via the reverse direction as LDH exhibits the oxidase activity (LDH-O). The hypothermal stress significantly upregulated the LDH-R activity in the muscles and the monocarboxylate transporter activity in both muscles and livers, of SW- and FW-acclimated milkfish. The levels of blood lactate, however, decreased in SW-acclimated milkfish. Under hypothermal stress, anaerobic metabolism increased in the muscles of both FW and SW individuals, whereas the liver of SW-acclimated milkfish showed better acute phase capacity to utilize blood lactate than FW-acclimated milkfish. Taken together, in the present study, the major functions of the bidirectional enzyme LDH were identified according to its LDH-O and LDH-R activities. Furthermore, environmental salinities were found to affect the acute anaerobic metabolic strategies of euryhaline teleosts under hypothermal stress and were correlated with their hypothermal tolerance ability.
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Affiliation(s)
- Chia-Hao Chang
- Department of Life Sciences, National Chung Hsing University, Taichung 402, Taiwan; The iEGG and Animal Biotechnology Center, National Chung Hsing University, Taichung 402, Taiwan
| | - Xiu-Wei Zhou
- Department of Life Sciences, National Chung Hsing University, Taichung 402, Taiwan
| | - Yu-Chun Wang
- Planning and Information Division, Fisheries Research Institute, Keelung 202, Taiwan
| | - Tsung-Han Lee
- Department of Life Sciences, National Chung Hsing University, Taichung 402, Taiwan; The iEGG and Animal Biotechnology Center, National Chung Hsing University, Taichung 402, Taiwan.
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11
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Conde-Sieira M, Capelli V, Álvarez-Otero R, Díaz-Rúa A, Velasco C, Comesaña S, López M, Soengas JL. Hypothalamic AMPKα2 regulates liver energy metabolism in rainbow trout through vagal innervation. Am J Physiol Regul Integr Comp Physiol 2019; 318:R122-R134. [PMID: 31692367 DOI: 10.1152/ajpregu.00264.2019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Hypothalamic AMPK plays a major role in the regulation of whole body metabolism and energy balance. Present evidence has demonstrated that this canonical mechanism is evolutionarily conserved. Thus, recent data demonstrated that inhibition of AMPKα2 in fish hypothalamus led to decreased food intake and liver capacity to use and synthesize glucose, lipids, and amino acids. We hypothesize that a signal of abundance of nutrients from the hypothalamus controls hepatic metabolism. The vagus nerve is the most important link between the brain and the liver. We therefore examined in the present study whether surgical transection of the vagus nerve in rainbow trout is sufficient to alter the effect in liver of central inhibition of AMPKα2. Thus, we vagotomized (VGX) or not (Sham) rainbow trout and then intracerebroventricularly administered adenoviral vectors tagged with green fluorescent protein alone or linked to a dominant negative isoform of AMPKα2. The inhibition of AMPKα2 led to reduced food intake in parallel with changes in the mRNA abundance of hypothalamic neuropeptides [neuropeptide Y (npy), agouti-related protein 1 (agrp1), and cocaine- and amphetamine-related transcript (cartpt)] involved in food intake regulation. Central inhibition of AMPKα2 resulted in the liver having decreased capacity to use and synthesize glucose, lipids, and amino acids. Notably, these effects mostly disappeared in VGX fish. These results support the idea that autonomic nervous system actions mediate the actions of hypothalamic AMPKα2 on liver metabolism. Importantly, this evidence indicates that the well-established role of hypothalamic AMPK in energy balance is a canonical evolutionarily preserved mechanism that is also present in the fish lineage.
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Affiliation(s)
- Marta Conde-Sieira
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
| | - Valentina Capelli
- Departamento de Fisiología, Grupo NeurObesity, Centro Singular de Investigación en Medicina Molecular y Enfermedades Crónicas, Universidade de Santiago de Compostela-Instituto de Investigación Sanitaria and Centro de Investigación Biomédica en Red-Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain.,Unit of Internal Medicine and Endocrinology, Istituti Clinici Scientifici Maugeri, Department of Internal Medicine and Therapeutics, University of Pavia, Pavia, Italy
| | - Rosa Álvarez-Otero
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
| | - Adrián Díaz-Rúa
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
| | - Cristina Velasco
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
| | - Sara Comesaña
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
| | - Miguel López
- Departamento de Fisiología, Grupo NeurObesity, Centro Singular de Investigación en Medicina Molecular y Enfermedades Crónicas, Universidade de Santiago de Compostela-Instituto de Investigación Sanitaria and Centro de Investigación Biomédica en Red-Fisiopatología de la Obesidad y Nutrición, Santiago de Compostela, Spain
| | - José L Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
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12
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Comesaña S, Velasco C, Conde-Sieira M, Otero-Rodiño C, Míguez JM, Soengas JL. Central Treatment of Ketone Body in Rainbow Trout Alters Liver Metabolism Without Apparently Altering the Regulation of Food Intake. Front Physiol 2019; 10:1206. [PMID: 31620022 PMCID: PMC6759561 DOI: 10.3389/fphys.2019.01206] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 09/04/2019] [Indexed: 12/03/2022] Open
Abstract
We hypothesize that the presence in fish brain of a ketone body (KB) like β-hydroxybutyrate (BHB) alters energy homeostasis through effects on food intake and peripheral energy metabolism. Using rainbow trout (Oncorhynchus mykiss) as a model, we intracerebroventricularly (ICV) administered 1 μl 100 g–1 body mass of saline solution alone (control) or containing 0.5 μmol of BHB. In a fist set of experiments, BHB did not affect food intake 6 and 24 h after treatment. In a second set of experiments, we evaluated 6 h after ICV BHB treatment changes in parameters putatively related to food intake control in brain areas (hypothalamus and hindbrain) involved in nutrient sensing and changes in energy metabolism in liver. The absence of changes in food intake might relate to the absence of major changes in the cascade of events from the detection of KB through ketone-sensing mechanisms, changes in transcription factors, and changes in the mRNA abundance of neuropeptides regulating food intake. This response is different than that of mammals. In contrast, central administration of BHB induced changes in liver energy metabolism suggesting a decreased use of glucose and probably an enhanced use of amino acid and lipid. These responses in liver are different to those of mammals under similar treatments but comparable to those occurring in fish under food deprivation conditions.
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Affiliation(s)
- Sara Comesaña
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Vigo, Spain
| | - Cristina Velasco
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Vigo, Spain
| | - Marta Conde-Sieira
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Vigo, Spain
| | - Cristina Otero-Rodiño
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Vigo, Spain
| | - Jesús M Míguez
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Vigo, Spain
| | - José L Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Vigo, Spain
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13
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Otero-Rodiño C, Conde-Sieira M, Comesaña S, Álvarez-Otero R, López-Patiño MA, Míguez JM, Soengas JL. Na +/K +-ATPase is involved in the regulation of food intake in rainbow trout but apparently not through brain glucosensing mechanisms. Physiol Behav 2019; 209:112617. [PMID: 31319109 DOI: 10.1016/j.physbeh.2019.112617] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/20/2019] [Accepted: 07/14/2019] [Indexed: 11/16/2022]
Abstract
To assess the hypothesis that Na+/K+-ATPase (NKA) is involved in the central regulation of food intake in fish, we observed in a first experiment with rainbow trout (Oncorhynchus mykiss) that intracerebroventricular (ICV) treatment with ouabain decreased food intake. We hypothesized that this effect relates to modulation of glucosensing mechanisms in brain areas (hypothalamus, hindbrain, and telencephalon) involved in food intake control. Therefore, we evaluated in a second experiment, the effect of ICV administration of ouabain, in the absence or in the presence of glucose, on NKA activity, mRNA abundance of different NKA subunits, parameters related to glucosensing, transcription factors, and appetite-related neuropeptides in brain areas involved in the control of food intake. NKA activity and mRNA abundance of nkaα1a and nkaα1c in brain were inhibited by ouabain treatment and partially by glucose. The anorectic effect of ouabain is opposed to the orexigenic effect reported in mammals. The difference might relate to the activity of glucosensing as well as downstream mechanisms involved in food intake regulation. Ouabain inhibited glucosensing mechanisms, which were activated by glucose in hypothalamus and telencephalon. Transcription factors and neuropeptides displayed responses comparable to those elicited by glucose when ouabain was administered alone, but not when glucose and ouabain were administered simultaneously. Ouabain might therefore affect other processes, besides glucosensing mechanisms, generating changes in membrane potential and/or intracellular pathways finally modulating transcription factors and neuropeptide mRNA abundance leading to modified food intake.
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Affiliation(s)
- Cristina Otero-Rodiño
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Spain
| | - Marta Conde-Sieira
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Spain
| | - Sara Comesaña
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Spain
| | - Rosa Álvarez-Otero
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Spain
| | - Marcos A López-Patiño
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Spain
| | - Jesús M Míguez
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Spain
| | - José L Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña-CIM, Universidade de Vigo, Spain.
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14
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Velasco C, Comesaña S, Conde-Sieira M, Míguez JM, Soengas JL. Effects of CCK-8 and GLP-1 on fatty acid sensing and food intake regulation in trout. J Mol Endocrinol 2019; 62:101-116. [PMID: 30608904 DOI: 10.1530/jme-18-0212] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 01/03/2019] [Indexed: 12/18/2022]
Abstract
We hypothesize that cholecystokinin (CCK) and glucagon-like peptide-1 (GLP-1) are involved in the modulation of metabolic regulation of food intake by fatty acids in fish. Therefore, we assessed in rainbow trout (Oncorhynchus mykiss) the effects of intracerebroventricular treatment with 1 ng/g of CCK-8 and with 2 ng/g of GLP-1 on food intake, expression of neuropeptides involved in food intake control and the activity of fatty acid-sensing systems in hypothalamus and hindbrain. Food intake decreased up to 24 h post-treatment to 49.8-72.3% and 3.1-17.8% for CCK-8 and GLP-1, respectively. These anorectic responses are associated with changes in fatty acid metabolism and an activation of fatty acid-sensing mechanisms in the hypothalamus and hindbrain. These changes occurred in parallel with those in the expression of anorexigenic and orexigenic peptides. Moreover, we observed that the activation of fatty acid sensing and the enhanced anorectic potential elicited by CCK-8 and GLP-1 treatments occurred in parallel with the activation of mTOR and FoxO1 and the inhibition of AMPKα, BSX and CREB. The results are discussed in the context of metabolic regulation of food intake in fish.
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Affiliation(s)
- Cristina Velasco
- Departamento de Bioloxía Funcional e Ciencias da Saúde, Laboratorio de Fisioloxía Animal, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
| | - Sara Comesaña
- Departamento de Bioloxía Funcional e Ciencias da Saúde, Laboratorio de Fisioloxía Animal, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
| | - Marta Conde-Sieira
- Departamento de Bioloxía Funcional e Ciencias da Saúde, Laboratorio de Fisioloxía Animal, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
| | - Jesús M Míguez
- Departamento de Bioloxía Funcional e Ciencias da Saúde, Laboratorio de Fisioloxía Animal, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
| | - José L Soengas
- Departamento de Bioloxía Funcional e Ciencias da Saúde, Laboratorio de Fisioloxía Animal, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
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15
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Differential Role of Hypothalamic AMPKα Isoforms in Fish: an Evolutive Perspective. Mol Neurobiol 2018; 56:5051-5066. [PMID: 30460617 DOI: 10.1007/s12035-018-1434-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Accepted: 11/15/2018] [Indexed: 12/11/2022]
Abstract
In mammals, hypothalamic AMP-activated protein kinase (AMPK) α1 and α2 isoforms mainly relate to regulation of thermogenesis/liver metabolism and food intake, respectively. Since both isoforms are present in fish, which do not thermoregulate, we assessed their role(s) in hypothalamus regarding control of food intake and energy homeostasis. Since many fish species are carnivorous and mostly mammals are omnivorous, assessing if the role of hypothalamic AMPK is different is also an open question. Using the rainbow trout as a fish model, we first observed that food deprivation for 5 days did not significantly increase phosphorylation status of AMPKα in hypothalamus. Then, we administered adenoviral vectors that express dominant negative (DN) AMPKα1 or AMPKα2 isoforms. The inhibition of AMPKα2 (but not AMPKα1) led to decreased food intake. The central inhibition of AMPKα2 resulted in liver with decreased capacity of use and synthesis of glucose, lipids, and amino acids suggesting that a signal of nutrient abundance flows from hypothalamus to the liver, thus suggesting a role for central AMPKα2 in the regulation of peripheral metabolism in fishes. The central inhibition of AMPKα1 induced comparable changes in liver metabolism though at a lower extent. From an evolutionary point of view, it is of interest that the function of central AMPKα2 remained similar throughout the vertebrate lineage. In contrast, the function of central AMPKα1 in fish relates to modulation of liver metabolism whereas in mammals modulates not only liver metabolism but also brown adipose tissue and thermogenesis.
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16
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Velasco C, Blanco AM, Unniappan S, Soengas JL. The anorectic effect of central PYY 1-36 treatment in rainbow trout (Oncorhynchus mykiss) is associated with changes in mRNAs encoding neuropeptides and parameters related to fatty acid sensing and metabolism. Gen Comp Endocrinol 2018; 267:137-145. [PMID: 29940182 DOI: 10.1016/j.ygcen.2018.06.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 06/18/2018] [Accepted: 06/21/2018] [Indexed: 12/21/2022]
Abstract
We hypothesized that peptide YY (PYY) is involved in the metabolic regulation of food intake in fish. Therefore, we assessed in rainbow trout (Oncorhynchus mykiss) the effects of intracerebroventricular treatment with 10 ng/g PYY1-36 on food intake, expression of neuropeptides involved in food intake control, and the activity of fatty acid-sensing systems. The administration of PYY1-36 caused a significant reduction in food intake up to 24 h post-treatment. This anorectic action was associated with changes 2 h after treatment in mRNA abundance of neuropeptides involved in metabolic regulation of food intake in hypothalamus (decreased NPY and raised CART values) and hindbrain (increased POMCa1 values). We also observed that PYY1-36 treatment induced changes in mRNA abundance of parameters related to fatty acid sensing and metabolism in hypothalamus (decreased values of ACLY, PPARγ, and SREBP1c) and hindbrain (increased values of LPL, FAT/CD36, PPARα, PPARγ, and SREBP1c and decreased values of UCP2a). PYY1-36 treatment also increased mRNA abundance of mTOR. In general, it seems that mRNAs encoding some components of the machinery required for fatty acid sensing and metabolism are activated by PYY1-36. The response observed was higher in the hindbrain than in the hypothalamus, supporting the greater importance of this brain area in mediating the modulatory effects of gastrointestinal hormones on feeding regulation.
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Affiliation(s)
- Cristina Velasco
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, 36310 Vigo, Spain; Laboratory of Integrative Neuroendrocrinology, Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, S7N 5B4 Saskatoon, Saskatchewan, Canada
| | - Ayelén M Blanco
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, 36310 Vigo, Spain; Laboratory of Integrative Neuroendrocrinology, Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, S7N 5B4 Saskatoon, Saskatchewan, Canada
| | - Suraj Unniappan
- Laboratory of Integrative Neuroendrocrinology, Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, S7N 5B4 Saskatoon, Saskatchewan, Canada.
| | - José L Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, 36310 Vigo, Spain
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17
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Conde-Sieira M, Ceinos RM, Velasco C, Comesaña S, López-Patiño MA, Míguez JM, Soengas JL. Response of rainbow trout’s (Oncorhynchus mykiss) hypothalamus to glucose and oleate assessed through transcription factors BSX, ChREBP, CREB, and FoxO1. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2018; 204:893-904. [DOI: 10.1007/s00359-018-1288-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 09/05/2018] [Accepted: 09/09/2018] [Indexed: 01/22/2023]
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18
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Soengas JL, Cerdá-Reverter JM, Delgado MJ. Central regulation of food intake in fish: an evolutionary perspective. J Mol Endocrinol 2018; 60:R171-R199. [PMID: 29467140 DOI: 10.1530/jme-17-0320] [Citation(s) in RCA: 71] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 02/21/2018] [Indexed: 12/11/2022]
Abstract
Evidence indicates that central regulation of food intake is well conserved along the vertebrate lineage, at least between teleost fish and mammals. However, several differences arise in the comparison between both groups. In this review, we describe similarities and differences between teleost fish and mammals on an evolutionary perspective. We focussed on the existing knowledge of specific fish features conditioning food intake, anatomical homologies and analogies between both groups as well as the main signalling pathways of neuroendocrine and metabolic nature involved in the homeostatic and hedonic central regulation of food intake.
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Affiliation(s)
- José Luis Soengas
- Departamento de Bioloxía Funcional e Ciencias da SaúdeLaboratorio de Fisioloxía Animal, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
| | - José Miguel Cerdá-Reverter
- Departamento de Fisiología de Peces y BiotecnologíaInstituto de Acuicultura Torre de la Sal, Consejo Superior de Investigaciones Científicas (CSIC), Castellón, Spain
| | - María Jesús Delgado
- Departamento de Fisiología (Fisiología Animal II)Facultad de Biología, Universidad Complutense de Madrid, Madrid, Spain
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19
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Otero-Rodiño C, Rocha A, Álvarez-Otero R, Ceinos RM, López-Patiño MA, Míguez JM, Cerdá-Reverter JM, Soengas JL. Glucosensing capacity of rainbow trout telencephalon. J Neuroendocrinol 2018; 30:e12583. [PMID: 29427522 DOI: 10.1111/jne.12583] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 02/01/2018] [Accepted: 02/04/2018] [Indexed: 12/28/2022]
Abstract
To assess the hypothesis of glucosensing systems present in fish telencephalon, we first demonstrated in rainbow trout, by in situ hybridisation, the presence of glucokinase (GK). Then, we assessed the response of glucosensing markers in rainbow trout telencephalon 6 hours after i.c.v. treatment with glucose or 2-deoxyglucose (inducing glucoprivation). We evaluated the response of parameters related to the mechanisms dependent on GK, liver X receptor (LXR), mitochondrial activity, sweet taste receptor and sodium-glucose linked transporter 1 (SGLT-1). We also assessed mRNA abundance of neuropeptides involved in the metabolic control of food intake (agouti-related protein, neuropeptide Y, pro-opiomelanocortin, and cocaine- and amphetamine-related transcript), as well as the abundance and phosphorylation status of proteins possibly involved in linking glucosensing with neuropeptide expression, such as protein kinase B (AkT), AMP-activated protein kinase (AMPK), mechanistic target of rapamycin and cAMP response element-binding protein (CREB). The responses obtained support the presence in the telencephalon of a glucosensing mechanism based on GK and maybe one based on LXR, although they do not support the presence of mechanisms dependent on mitochondrial activity and SGLT-1. The mechanism based on sweet taste receptor responded to glucose but in a converse way to that characterised previously in the hypothalamus. In general, systems responded only to glucose but not to glucoprivation. Neuropeptides did not respond to glucose or glucoprivation. By contrast, the presence of glucose activates Akt and inhibits AMPK, CREB and forkhead box01. This is the first study in any vertebrate species in which the response to glucose of putative glucosensing mechanisms is demonstrated in the telencephalon. Their role might relate to processes other than homeostatic control of food intake, such as the hedonic and reward system.
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Affiliation(s)
- C Otero-Rodiño
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
| | - A Rocha
- Departamento de Fisiología de Peces y Biotecnología, Instituto de Acuicultura Torre de la Sal, Consejo Superior de Investigaciones Científicas (CSIC), Castellón, Spain
| | - R Álvarez-Otero
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
| | - R M Ceinos
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
| | - M A López-Patiño
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
| | - J M Míguez
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
| | - J M Cerdá-Reverter
- Departamento de Fisiología de Peces y Biotecnología, Instituto de Acuicultura Torre de la Sal, Consejo Superior de Investigaciones Científicas (CSIC), Castellón, Spain
| | - J L Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
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Comesaña S, Velasco C, Ceinos RM, López-Patiño MA, Míguez JM, Morais S, Soengas JL. Evidence for the presence in rainbow trout brain of amino acid-sensing systems involved in the control of food intake. Am J Physiol Regul Integr Comp Physiol 2018; 314:R201-R215. [DOI: 10.1152/ajpregu.00283.2017] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
To assess the hypothesis of central amino acid-sensing systems involved in the control of food intake in fish, we carried out two experiments in rainbow trout. In the first one, we injected intracerebroventricularly two different branched-chain amino acids (BCAAs), leucine and valine, and assessed food intake up to 48 h later. Leucine decreased and valine increased food intake. In a second experiment, 6 h after similar intracerebroventricular treatment we determined changes in parameters related to putative amino acid-sensing systems. Different areas of rainbow trout brain present amino acid-sensing systems responding to leucine (hypothalamus and telencephalon) and valine (telencephalon), while other areas (midbrain and hindbrain) do not respond to these treatments. The decreased food intake observed in fish treated intracerebroventricularly with leucine could relate to changes in mRNA abundance of hypothalamic neuropeptides [proopiomelanocortin (POMC), cocaine- and amphetamine-related transcript (CART), neuropeptide Y (NPY), and agouti-related peptide (AgRP)]. These in turn could relate to amino acid-sensing systems present in the same area, related to BCAA and glutamine metabolism, as well as mechanistic target of rapamycin (mTOR), taste receptors, and general control nonderepressible 2 (GCN2) kinase signaling. The treatment with valine did not affect amino acid-sensing parameters in the hypothalamus. These responses are comparable to those characterized in mammals. However, clear differences arise when comparing rainbow trout and mammals, in particular with respect to the clear orexigenic effect of valine, which could relate to the finding that valine partially stimulated two amino acid-sensing systems in the telencephalon. Another novel result is the clear effect of leucine on telencephalon, in which amino acid-sensing systems, but not neuropeptides, were activated as in the hypothalamus.
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Affiliation(s)
- Sara Comesaña
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro Singular de Investigación Mariña-ECIMAT, Universidade de Vigo, Vigo, Spain
| | - Cristina Velasco
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro Singular de Investigación Mariña-ECIMAT, Universidade de Vigo, Vigo, Spain
| | - Rosa M. Ceinos
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro Singular de Investigación Mariña-ECIMAT, Universidade de Vigo, Vigo, Spain
| | - Marcos A. López-Patiño
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro Singular de Investigación Mariña-ECIMAT, Universidade de Vigo, Vigo, Spain
| | - Jesús M. Míguez
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro Singular de Investigación Mariña-ECIMAT, Universidade de Vigo, Vigo, Spain
| | - Sofia Morais
- Lucta, Innovation Division, Autonomous University of Barcelona Research Park, Bellaterra, Spain
| | - José L. Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro Singular de Investigación Mariña-ECIMAT, Universidade de Vigo, Vigo, Spain
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21
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Delgado MJ, Cerdá-Reverter JM, Soengas JL. Hypothalamic Integration of Metabolic, Endocrine, and Circadian Signals in Fish: Involvement in the Control of Food Intake. Front Neurosci 2017; 11:354. [PMID: 28694769 PMCID: PMC5483453 DOI: 10.3389/fnins.2017.00354] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2016] [Accepted: 06/07/2017] [Indexed: 12/12/2022] Open
Abstract
The regulation of food intake in fish is a complex process carried out through several different mechanisms in the central nervous system (CNS) with hypothalamus being the main regulatory center. As in mammals, a complex hypothalamic circuit including two populations of neurons: one co-expressing neuropeptide Y (NPY) and Agouti-related peptide (AgRP) and the second one population co-expressing pro-opiomelanocortin (POMC) and cocaine- and amphetamine-regulated transcript (CART) is involved in the integration of information relating to food intake control. The production and release of these peptides control food intake, and the production results from the integration of information of different nature such as levels of nutrients and hormones as well as circadian signals. The present review summarizes the knowledge and recent findings about the presence and functioning of these mechanisms in fish and their differences vs. the known mammalian model.
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Affiliation(s)
- María J. Delgado
- Departamento de Fisiología (Fisiología Animal II), Facultad de Biología, Universidad Complutense de MadridMadrid, Spain
| | - José M. Cerdá-Reverter
- Departamento de Fisiología de Peces y Biotecnología, Instituto de Acuicultura Torre de la Sal, Consejo Superior de Investigaciones CientíficasCastellón, Spain
| | - José L. Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de VigoVigo, Spain
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22
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Velasco C, Moreiras G, Conde-Sieira M, Leao JM, Míguez JM, Soengas JL. Ceramide counteracts the effects of ghrelin on the metabolic control of food intake in rainbow trout. ACTA ACUST UNITED AC 2017; 220:2563-2576. [PMID: 28495865 DOI: 10.1242/jeb.159871] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 05/02/2017] [Indexed: 12/31/2022]
Abstract
In mammals, ceramides are involved in the modulation of the orexigenic effects of ghrelin (GHRL). We previously demonstrated in rainbow trout that intracerebroventricular (ICV) treatment with ceramide (2.5 µg/100 g fish) resulted in an anorexigenic response, i.e. a response opposed to that described in mammals, where ceramide treatment is orexigenic. Therefore, we hypothesized that the putative interaction between GHRL and ceramide must be different in fish. Accordingly, in a first experiment, we observed that ceramide levels in the hypothalamus of rainbow trout did not change after ICV treatment with GHRL. In a second experiment, we assessed whether the effects of GHRL treatment on the regulation of food intake in rainbow trout changed in the presence of ceramide. Thus, we injected ICV GHRL and ceramide alone or in combination to evaluate in hypothalamus and hindbrain changes in parameters related to the metabolic control of food intake. The presence of ceramide generally counteracted the effects elicited by GHRL on fatty acid-sensing systems, the capacity of integrative sensors (AMPK, mTOR and SIRT-1), proteins involved in cellular signalling pathways (Akt and FoxO1) and neuropeptides involved in the regulation of food intake (AgRP, NPY, POMC and CART). The results are discussed in the context of regulation of food intake by metabolic and endocrine inputs.
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Affiliation(s)
- Cristina Velasco
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro Singular de Investigación Mariña-ECIMAT, Universidade de Vigo, 36310 Vigo, Spain
| | - Guillermo Moreiras
- Departamento de Química Analítica e Alimentaria, Facultade de Química, Universidade de Vigo, 36310 Vigo, Spain
| | - Marta Conde-Sieira
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro Singular de Investigación Mariña-ECIMAT, Universidade de Vigo, 36310 Vigo, Spain
| | - José M Leao
- Departamento de Química Analítica e Alimentaria, Facultade de Química, Universidade de Vigo, 36310 Vigo, Spain
| | - Jesús M Míguez
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro Singular de Investigación Mariña-ECIMAT, Universidade de Vigo, 36310 Vigo, Spain
| | - José L Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía and Centro Singular de Investigación Mariña-ECIMAT, Universidade de Vigo, 36310 Vigo, Spain
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Marandel L, Panserat S, Plagnes-Juan E, Arbenoits E, Soengas JL, Bobe J. Evolutionary history of glucose-6-phosphatase encoding genes in vertebrate lineages: towards a better understanding of the functions of multiple duplicates. BMC Genomics 2017; 18:342. [PMID: 28464795 PMCID: PMC5414149 DOI: 10.1186/s12864-017-3727-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2016] [Accepted: 04/26/2017] [Indexed: 12/20/2022] Open
Abstract
Background Glucose-6-phosphate (G6pc) is a key enzyme involved in the regulation of the glucose homeostasis. The present study aims at revisiting and clarifying the evolutionary history of g6pc genes in vertebrates. Results g6pc duplications happened by successive rounds of whole genome duplication that occurred during vertebrate evolution. g6pc duplicated before or around Osteichthyes/Chondrichthyes radiation, giving rise to g6pca and g6pcb as a consequence of the second vertebrate whole genome duplication. g6pca was lost after this duplication in Sarcopterygii whereas both g6pca and g6pcb then duplicated as a consequence of the teleost-specific whole genome duplication. One g6pca duplicate was lost after this duplication in teleosts. Similarly one g6pcb2 duplicate was lost at least in the ancestor of percomorpha. The analysis of the evolution of spatial expression patterns of g6pc genes in vertebrates showed that all g6pc were mainly expressed in intestine and liver whereas teleost-specific g6pcb2 genes were mainly and surprisingly expressed in brain and heart. g6pcb2b, one gene previously hypothesised to be involved in the glucose intolerant phenotype in trout, was unexpectedly up-regulated (as it was in liver) by carbohydrates in trout telencephalon without showing significant changes in other brain regions. This up-regulation is in striking contrast with expected glucosensing mechanisms suggesting that its positive response to glucose relates to specific unknown processes in this brain area. Conclusions Our results suggested that the fixation and the divergence of g6pc duplicated genes during vertebrates’ evolution may lead to adaptive novelty and probably to the emergence of novel phenotypes related to glucose homeostasis. Electronic supplementary material The online version of this article (doi:10.1186/s12864-017-3727-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lucie Marandel
- INRA, UPPA, UMR 1419 Nutrition, Metabolism, Aquaculture, F-64310, Saint Pée sur Nivelle, France.
| | - Stéphane Panserat
- INRA, UPPA, UMR 1419 Nutrition, Metabolism, Aquaculture, F-64310, Saint Pée sur Nivelle, France
| | - Elisabeth Plagnes-Juan
- INRA, UPPA, UMR 1419 Nutrition, Metabolism, Aquaculture, F-64310, Saint Pée sur Nivelle, France
| | - Eva Arbenoits
- INRA, UPPA, UMR 1419 Nutrition, Metabolism, Aquaculture, F-64310, Saint Pée sur Nivelle, France
| | - José Luis Soengas
- Departamento de Bioloxía Funcional e Ciencias da Saúde, Laboratorio de Fisioloxía Animal, Facultade de Bioloxía, Universidade de Vigo, E-36310, Vigo, Spain
| | - Julien Bobe
- INRA, UR1037 LPGP, Campus de Beaulieu, F-35000, Rennes, France
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Conde-Sieira M, Soengas JL. Nutrient Sensing Systems in Fish: Impact on Food Intake Regulation and Energy Homeostasis. Front Neurosci 2017; 10:603. [PMID: 28111540 PMCID: PMC5216673 DOI: 10.3389/fnins.2016.00603] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 12/19/2016] [Indexed: 12/27/2022] Open
Abstract
Evidence obtained in recent years in a few species, especially rainbow trout, supports the presence in fish of nutrient sensing mechanisms. Glucosensing capacity is present in central (hypothalamus and hindbrain) and peripheral [liver, Brockmann bodies (BB, main accumulation of pancreatic endocrine cells in several fish species), and intestine] locations whereas fatty acid sensors seem to be present in hypothalamus, liver and BB. Glucose and fatty acid sensing capacities relate to food intake regulation and metabolism in fish. Hypothalamus is as a signaling integratory center in a way that detection of increased levels of nutrients result in food intake inhibition through changes in the expression of anorexigenic and orexigenic neuropeptides. Moreover, central nutrient sensing modulates functions in the periphery since they elicit changes in hepatic metabolism as well as in hormone secretion to counter-regulate changes in nutrient levels detected in the CNS. At peripheral level, the direct nutrient detection in liver has a crucial role in homeostatic control of glucose and fatty acid whereas in BB and intestine nutrient sensing is probably involved in regulation of hormone secretion from endocrine cells.
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Affiliation(s)
- Marta Conde-Sieira
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo Vigo, Spain
| | - José L Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo Vigo, Spain
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Velasco C, Librán-Pérez M, Otero-Rodiño C, López-Patiño MA, Míguez JM, Soengas JL. Ceramides are involved in the regulation of food intake in rainbow trout (Oncorhynchus mykiss). Am J Physiol Regul Integr Comp Physiol 2016; 311:R658-R668. [PMID: 27465737 DOI: 10.1152/ajpregu.00201.2016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 07/27/2016] [Indexed: 12/11/2022]
Abstract
We hypothesize that ceramides are involved in the regulation of food intake in fish. Therefore, we assessed in rainbow trout (Oncorhynchus mykiss) the effects of intracerebroventricular treatment with C6:0 ceramide on food intake. In a second experiment, we assessed the effects in brain areas of ceramide treatment on neuropeptide expression, fatty acid-sensing systems, and cellular signaling pathways. Ceramide treatment induced a decrease in food intake, a response opposed to the orexigenic effect described in mammals, which can be related to enhanced mRNA abundance of cocaine and amphetamine-related transcript and proopiomelanocortin and decreased mRNA abundance of Agouti-related protein and neuropeptide Y. Fatty acid-sensing systems appear to be inactivated by ceramide treatment. The mRNA abundance of integrative sensors AMPK and sirtuin 1, and the phosphorylation status of cellular signaling pathways dependent on protein kinase B, AMPK, mammalian target of rapamycin (mTOR), and forkhead box protein O1 (FoxO1) are generally activated by ceramide treatment. However, there are differences between hypothalamus and hindbrain in the phosphorylation status of AMPK (decreased in hypothalamus and increased in hindbrain), mTOR (decreased in hypothalamus and increased in hindbrain), and FoxO1 (increased in hypothalamus and decreased in hindbrain) to ceramide treatment. The results suggest that ceramides are involved in the regulation of food intake in rainbow trout through mechanisms comparable to those characterized previously in mammals in some cases.
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Affiliation(s)
- Cristina Velasco
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo, Spain
| | - Marta Librán-Pérez
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo, Spain
| | - Cristina Otero-Rodiño
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo, Spain
| | - Marcos A López-Patiño
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo, Spain
| | - Jesús M Míguez
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo, Spain
| | - José L Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo, Spain
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26
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Velasco C, Librán-Pérez M, Otero-Rodiño C, López-Patiño MA, Míguez JM, Soengas JL. Intracerebroventricular ghrelin treatment affects lipid metabolism in liver of rainbow trout (Oncorhynchus mykiss). Gen Comp Endocrinol 2016; 228:33-39. [PMID: 26828819 DOI: 10.1016/j.ygcen.2016.01.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 01/22/2016] [Accepted: 01/28/2016] [Indexed: 12/21/2022]
Abstract
We aimed to elucidate in rainbow trout (Oncorhynchus mykiss) the effects of central ghrelin (GHRL) treatment on the regulation of liver lipid metabolism, and the possible modulatory effect of central GHRL treatment on the simultaneous effects of raised levels of oleate. Thus, we injected intracerebroventricularly (ICV) rainbow trout GHRL in the presence or absence of oleate and evaluated in liver variables related to lipid metabolism. Oleate treatment elicited in liver of rainbow trout decreased lipogenesis and increased oxidative capacity in agreement with previous studies. Moreover, as demonstrated for the first time in fish in the present study, GHRL also acts centrally modulating lipid metabolism in liver, resulting in increased potential for lipogenesis and decreased potential for fatty acid oxidation, i.e. the converse effects to those elicited by central oleate treatment. The simultaneous treatment of GHRL and oleate confirmed these counteractive effects. Thus, the nutrient sensing mechanisms present in hypothalamus, particularly those involved in sensing of fatty acid, are involved in the control of liver energy metabolism in fish, and this control is modulated by the central action of GHRL. These results give support to the notion of hypothalamus as an integrative place for the regulation of peripheral energy metabolism in fish.
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Affiliation(s)
- Cristina Velasco
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, Spain
| | - Marta Librán-Pérez
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, Spain
| | - Cristina Otero-Rodiño
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, Spain
| | - Marcos A López-Patiño
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, Spain
| | - Jesús M Míguez
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, Spain
| | - José L Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, Spain.
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27
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Velasco C, Librán-Pérez M, Otero-Rodiño C, López-Patiño MA, Míguez JM, Cerdá-Reverter JM, Soengas JL. Ghrelin modulates hypothalamic fatty acid-sensing and control of food intake in rainbow trout. J Endocrinol 2016; 228:25-37. [PMID: 26459641 DOI: 10.1530/joe-15-0391] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/12/2015] [Indexed: 12/17/2022]
Abstract
There is no information available on fish as far as the possible effects of ghrelin on hypothalamic fatty acid metabolism and the response of fatty acid-sensing systems, which are involved in the control of food intake. Therefore, we assessed in rainbow trout the response of food intake, hypothalamic fatty acid-sensing mechanisms and expression of neuropeptides involved in the control of food intake to the central treatment of ghrelin in the presence or absence of a long-chain fatty acid such as oleate. We observed that the orexigenic actions of ghrelin in rainbow trout are associated with changes in fatty acid metabolism in the hypothalamus and an inhibition of fatty acid-sensing mechanisms, which ultimately lead to changes in the expression of anorexigenic and orexigenic peptides resulting in increased orexigenic potential and food intake. Moreover, the response to increased levels of oleate of hypothalamic fatty acid-sensing systems (activation), expression of neuropeptides (enhanced anorexigenic potential) and food intake (decrease) were counteracted by the simultaneous treatment with ghrelin. These changes provide evidence for the first time in fish of a possible modulatory role of ghrelin on the metabolic regulation by fatty acid of food intake occurring in the hypothalamus.
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Affiliation(s)
- Cristina Velasco
- Laboratorio de Fisioloxía AnimalDepartamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, SpainDepartamento de Fisiología de Peces y BiotecnologíaInstituto de Acuicultura Torre de la Sal, Consejo Superior de Investigaciones Científicas (CSIC), Castellón, Spain
| | - Marta Librán-Pérez
- Laboratorio de Fisioloxía AnimalDepartamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, SpainDepartamento de Fisiología de Peces y BiotecnologíaInstituto de Acuicultura Torre de la Sal, Consejo Superior de Investigaciones Científicas (CSIC), Castellón, Spain
| | - Cristina Otero-Rodiño
- Laboratorio de Fisioloxía AnimalDepartamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, SpainDepartamento de Fisiología de Peces y BiotecnologíaInstituto de Acuicultura Torre de la Sal, Consejo Superior de Investigaciones Científicas (CSIC), Castellón, Spain
| | - Marcos A López-Patiño
- Laboratorio de Fisioloxía AnimalDepartamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, SpainDepartamento de Fisiología de Peces y BiotecnologíaInstituto de Acuicultura Torre de la Sal, Consejo Superior de Investigaciones Científicas (CSIC), Castellón, Spain
| | - Jesús M Míguez
- Laboratorio de Fisioloxía AnimalDepartamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, SpainDepartamento de Fisiología de Peces y BiotecnologíaInstituto de Acuicultura Torre de la Sal, Consejo Superior de Investigaciones Científicas (CSIC), Castellón, Spain
| | - José Miguel Cerdá-Reverter
- Laboratorio de Fisioloxía AnimalDepartamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, SpainDepartamento de Fisiología de Peces y BiotecnologíaInstituto de Acuicultura Torre de la Sal, Consejo Superior de Investigaciones Científicas (CSIC), Castellón, Spain
| | - José L Soengas
- Laboratorio de Fisioloxía AnimalDepartamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, SpainDepartamento de Fisiología de Peces y BiotecnologíaInstituto de Acuicultura Torre de la Sal, Consejo Superior de Investigaciones Científicas (CSIC), Castellón, Spain
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28
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Otero-Rodiño C, Librán-Pérez M, Velasco C, Álvarez-Otero R, López-Patiño MA, Míguez JM, Soengas JL. Response of lactate metabolism in brain glucosensing areas of rainbow trout (Oncorhynchus mykiss) to changes in glucose levels. J Comp Physiol B 2015; 185:869-82. [DOI: 10.1007/s00360-015-0932-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 09/03/2015] [Accepted: 09/15/2015] [Indexed: 12/18/2022]
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29
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Soengas JL. Contribution of glucose- and fatty acid sensing systems to the regulation of food intake in fish. A review. Gen Comp Endocrinol 2014; 205:36-48. [PMID: 24530522 DOI: 10.1016/j.ygcen.2014.01.015] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Revised: 01/13/2014] [Accepted: 01/28/2014] [Indexed: 01/01/2023]
Abstract
Food intake in fish is a complex process regulated through many different factors including abundance of energy and nutrients. In recent years, evidence have been obtained in several fishes, mainly in rainbow trout, regarding the presence and functioning in brain areas of metabolic sensors informing about changes in the levels of nutrients like glucose and fatty acids. The activity of these sensors relate to the control of food intake through changes in the expression of anorexigenic and orexigenic neuropeptides. The present review will provide a picture of the main results obtained to date in these studies, as well as perspectives for future research in the field.
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Affiliation(s)
- José L Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Spain.
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30
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Tseng YC, Liu ST, Hu MY, Chen RD, Lee JR, Hwang PP. Brain functioning under acute hypothermic stress supported by dynamic monocarboxylate utilization and transport in ectothermic fish. Front Zool 2014. [DOI: 10.1186/s12983-014-0053-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Abstract
The glucokinase (GK) enzyme (EC 2.7.1.1.) is essential for the use of dietary glucose because it is the first enzyme to phosphorylate glucose in excess in different key tissues such as the pancreas and liver. The objective of the present review is not to fully describe the biochemical characteristics and the genetics of this enzyme but to detail its nutritional regulation in different vertebrates from fish to human. Indeed, the present review will describe the existence of the GK enzyme in different animal species that have naturally different levels of carbohydrate in their diets. Thus, some studies have been performed to analyse the nutritional regulation of the GK enzyme in humans and rodents (having high levels of dietary carbohydrates in their diets), in the chicken (moderate level of carbohydrates in its diet) and rainbow trout (no carbohydrate intake in its diet). All these data illustrate the nutritional importance of the GK enzyme irrespective of feeding habits, even in animals known to poorly use dietary carbohydrates (carnivorous species).
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Librán-Pérez M, Otero-Rodiño C, López-Patiño MA, Míguez JM, Soengas JL. Central administration of oleate or octanoate activates hypothalamic fatty acid sensing and inhibits food intake in rainbow trout. Physiol Behav 2014; 129:272-9. [PMID: 24631300 DOI: 10.1016/j.physbeh.2014.02.061] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Revised: 02/05/2014] [Accepted: 02/20/2014] [Indexed: 01/23/2023]
Abstract
If levels of fatty acids like oleate and octanoate are directly sensed through different fatty acid (FA) sensing systems in hypothalamus of rainbow trout, intracerebroventricular (ICV) administration of FA should elicit effects similar to those previously observed after intraperitoneal (IP) treatment. Accordingly, we observed after ICV treatment with oleate or octanoate decreased food intake accompanied in hypothalamus by reduced potential of lipogenesis and FA oxidation, and decreased potential of ATP-dependent inward rectifier potassium channel (K(+)ATP). Those changes support direct FA sensing through mechanisms related to FA metabolism and mitochondrial activity. The FA sensing through binding to FAT/CD36 and subsequent expression of transcription factors appears to be also direct but an interaction with peripheral hormones cannot be rejected. Moreover, decreased expression of NPY and increased expression of POMC were observed in parallel with the activation of FA sensing systems and decreased food intake. These results allow us to suggest the involvement of at least these peptides in controlling the decreased food intake noted after oleate and octanoate treatment in rainbow trout.
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Affiliation(s)
- Marta Librán-Pérez
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, Spain
| | - Cristina Otero-Rodiño
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, Spain
| | - Marcos A López-Patiño
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, Spain
| | - Jesús M Míguez
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, Spain
| | - José L Soengas
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, Spain.
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Das M, Banerjee B, Choudhury MG, Saha N. Environmental hypertonicity causes induction of gluconeogenesis in the air-breathing singhi catfish, Heteropneustes fossilis. PLoS One 2013; 8:e85535. [PMID: 24376888 PMCID: PMC3869940 DOI: 10.1371/journal.pone.0085535] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Accepted: 11/27/2013] [Indexed: 02/01/2023] Open
Abstract
The air-breathing singhi catfish (Heteropneustes fossilis) is frequently being challenged by different environmental insults such as hyper-ammonia, dehydration and osmotic stresses in their natural habitats throughout the year. The present study investigated the effect of hyperosmotic stress, due to exposure to hypertonic environment (300 mM mannitol) for 14 days, on gluconeogenesis in this catfish. In situ exposure to hypertonic environment led to significant stimulation of gluconeogenic fluxes from the perfused liver after 7 days of exposure, followed by further increase after 14 days in presence of three different potential gluconeogenic substrates (lactate, pyruvate and glutamate). Environmental hypertonicity also caused a significant increase of activities of key gluconeogenic enzymes, namely phosphoenolpyruvate carboxykinase, fructose 1, 6-bisphosphatase and glucose 6-phosphatase by about 2-6 fold in liver, and 3-6 fold in kidney tissues. This was accompanied by more abundance of enzyme proteins by about 1.8–3.7 fold and mRNAs by about 2.2–5.2 fold in both the tissues with a maximum increase after 14 days of exposure. Hence, the increase in activities of key gluconeogenic enzymes under hypertonic stress appeared to be as a result of transcriptional regulation of genes. Immunocytochemical analysis further confirmed the tissue specific localized expression of these enzymes in both the tissues with the possibility of expressing more in the same localized places. The induction of gluconeogenesis during exposure to environmental hypertonicity possibly occurs as a consequence of changes in hydration status/cell volume of different cell types. Thus, these adaptational strategies related to gluconeogenesis that are observed in this catfish under hypertonic stress probably help in maintaining glucose homeostasis and also for a proper energy supply to support metabolic demands mainly for ion transport and other altered metabolic processes under various environmental hypertonic stress-related insults.
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Affiliation(s)
- Manas Das
- Biochemical Adaptation Laboratory, Department of Zoology, North-Eastern Hill University, Shillong, India
| | - Bodhisattwa Banerjee
- Biochemical Adaptation Laboratory, Department of Zoology, North-Eastern Hill University, Shillong, India
| | - Mahua G. Choudhury
- Biochemical Adaptation Laboratory, Department of Zoology, North-Eastern Hill University, Shillong, India
| | - Nirmalendu Saha
- Biochemical Adaptation Laboratory, Department of Zoology, North-Eastern Hill University, Shillong, India
- * E-mail:
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Programming effects of high-carbohydrate feeding of larvae on adult glucose metabolism in zebrafish, Danio rerio. Br J Nutr 2013; 111:808-18. [PMID: 24112146 DOI: 10.1017/s0007114513003243] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The aim of the present study was to determine the potential long-term metabolic effects of early nutritional programming on carbohydrate utilisation in adult zebrafish (Danio rerio). High-carbohydrate diets were fed to fish during four ontogenetic stages: from the first-feeding stage to the end of the yolk-sac larval stage; from the first-feeding stage to 2 d after yolk-sac exhaustion; after yolk-sac exhaustion for 3 or 5 d. The carbohydrate stimuli significantly increased the body weight of the first-feeding groups in the short term. The expression of genes was differentially regulated by the early dietary intervention. The high-carbohydrate diets resulted in decreased plasma glucose levels in the adult fish. The mRNA levels and enzyme activities of glucokinase, pyruvate kinase, α-amylase and sodium-dependent glucose co-transporter 1 were up-regulated in the first-feeding groups. There was no significant change in the mRNA levels of glucose-6-phosphatase (G6Pase) in any experimental group, and the activity of G6Pase enzyme in the FF-5 (first feeding to 2 d after yolk-sac exhaustion) group was significantly different from that of the other groups. The expression of phosphoenolpyruvate carboxykinase gene in all the groups was significantly decreased. In the examined early programming range, growth performance was not affected. Taken together, data reported herein indicate that the period ranging from the polyculture to the external feeding stage is an important window for potential modification of the long-term physiological functions. In conclusion, the present study demonstrates that it is possible to permanently modify carbohydrate digestion, transport and metabolism of adult zebrafish through early nutritional programming.
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Neves A, Costalat R, Pellerin L. Determinants of brain cell metabolic phenotypes and energy substrate utilization unraveled with a modeling approach. PLoS Comput Biol 2012; 8:e1002686. [PMID: 23028284 PMCID: PMC3441424 DOI: 10.1371/journal.pcbi.1002686] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2012] [Accepted: 07/23/2012] [Indexed: 12/31/2022] Open
Abstract
Although all brain cells bear in principle a comparable potential in terms of energetics, in reality they exhibit different metabolic profiles. The specific biochemical characteristics explaining such disparities and their relative importance are largely unknown. Using a modeling approach, we show that modifying the kinetic parameters of pyruvate dehydrogenase and mitochondrial NADH shuttling within a realistic interval can yield a striking switch in lactate flux direction. In this context, cells having essentially an oxidative profile exhibit pronounced extracellular lactate uptake and consumption. However, they can be turned into cells with prominent aerobic glycolysis by selectively reducing the aforementioned parameters. In the case of primarily oxidative cells, we also examined the role of glycolysis and lactate transport in providing pyruvate to mitochondria in order to sustain oxidative phosphorylation. The results show that changes in lactate transport capacity and extracellular lactate concentration within the range described experimentally can sustain enhanced oxidative metabolism upon activation. Such a demonstration provides key elements to understand why certain brain cell types constitutively adopt a particular metabolic profile and how specific features can be altered under different physiological and pathological conditions in order to face evolving energy demands. In an environment with appropriate oxygen levels (normoxia), most eukaryotic cells produce energy by oxidizing glucose into carbon dioxide and water. In this process, glucose is transformed into pyruvate, which then fuels oxidative phosphorylation in the mitochondria. Interestingly, Otto Warburg reported back in the 1920's that some eukaryotic cells prominently process glucose-derived pyruvate into lactate, hence “avoiding" the mitochondrial oxidation despite adequate oxygen concentrations. This phenomenon was termed aerobic glycolysis and was first observed in cancer cells. Since then, it has also been described in several normal tissues including the central nervous system. The biochemical basis of aerobic glycolysis has remained elusive until now. Taking advantage of a modeling approach, we unraveled the main metabolic characteristics that determine whether a cell will be strictly oxidative or rather will exhibit aerobic glycolysis. When applied in the context of the central nervous system, our findings not only provide a theoretical demonstration of why neurons and astrocytes differ in terms of metabolic profile, but also suggest that such complementarity forms the basis for metabolic cooperation between the two cell types.
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Affiliation(s)
- Aitana Neves
- Département de Physiologie, Université de Lausanne, Lausanne, Switzerland
| | | | - Luc Pellerin
- Département de Physiologie, Université de Lausanne, Lausanne, Switzerland
- * E-mail:
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Roques JAC, Abbink W, Chereau G, Fourneyron A, Spanings T, Burggraaf D, van de Bos R, van de Vis H, Flik G. Physiological and behavioral responses to an electrical stimulus in Mozambique tilapia (Oreochromis mossambicus). FISH PHYSIOLOGY AND BIOCHEMISTRY 2012; 38:1019-1028. [PMID: 22198161 PMCID: PMC3389246 DOI: 10.1007/s10695-011-9586-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Accepted: 12/05/2011] [Indexed: 05/31/2023]
Abstract
Consumer awareness of the need to improve fish welfare is increasing. Electrostunning is a clean and potentially efficient procedure more and more used to provoke loss of consciousness prior to killing or slaughtering (reviewed by Van de Vis et al. in Aquac Res 34:211-220, 2003). Little is known how (powerful) electrical stimuli, which do not stun immediately, are perceived by fish. We investigated responses of hand-held Mozambique tilapia (Oreochromis mossambicus) to a standardized electric shock applied to the tailfin. The handling with the resulting unavoidable acute stress response was carefully controlled for. Fish responses were analyzed up to 24 h following the shock. Electric shock resulted in slightly higher levels in plasma cortisol, lactate, ionic levels, and osmolality, than handling alone. Plasma glucose had significantly increased 6 h after shock compared to handling, indicative of enhanced adrenergic activity. Mucus release from the gills, branchial Na⁺/K⁺ ATPase activity, and chloride cell migration and proliferation, parameters that will change with strong adrenergic activation, were not affected. Decreased swimming activity and delay in resumption of chafing behavior indicated a stronger and differential response toward the electric shock. Responses to handling lasted shorter compared to those to an electric shock. The differential and stronger responses to the electric shock suggest that fish perceived the shock potentially as painful.
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Affiliation(s)
- Jonathan A C Roques
- Department of Animal Physiology, Faculty of Science, Institute for Water and Wetland Research, Radboud University Nijmegen, Heyendaalseweg 135, Box 30, 6525 AJ, Nijmegen, The Netherlands
- Department of Aquaculture, IMARES Wageningen UR, Institute for Marine Resources and Ecosystem Studies, P.O. Box 77, 4400 AB, Yerseke, The Netherlands
| | - Wout Abbink
- Department of Aquaculture, IMARES Wageningen UR, Institute for Marine Resources and Ecosystem Studies, P.O. Box 77, 4400 AB, Yerseke, The Netherlands
| | - Gaétan Chereau
- Department of Animal Physiology, Faculty of Science, Institute for Water and Wetland Research, Radboud University Nijmegen, Heyendaalseweg 135, Box 30, 6525 AJ, Nijmegen, The Netherlands
| | - Aurélie Fourneyron
- Department of Animal Physiology, Faculty of Science, Institute for Water and Wetland Research, Radboud University Nijmegen, Heyendaalseweg 135, Box 30, 6525 AJ, Nijmegen, The Netherlands
| | - Tom Spanings
- Department of Animal Physiology, Faculty of Science, Institute for Water and Wetland Research, Radboud University Nijmegen, Heyendaalseweg 135, Box 30, 6525 AJ, Nijmegen, The Netherlands
| | - Dirk Burggraaf
- Department of Aquaculture, IMARES Wageningen UR, Institute for Marine Resources and Ecosystem Studies, P.O. Box 77, 4400 AB, Yerseke, The Netherlands
| | - Ruud van de Bos
- Department of Animals in Science and Society, Division of Behavioural Neuroscience, Faculty of Veterinary Medicine, Utrecht University, PO Box 80.166, 3508 TD, Utrecht, The Netherlands
| | - Hans van de Vis
- Department of Aquaculture, IMARES Wageningen UR, Institute for Marine Resources and Ecosystem Studies, P.O. Box 77, 4400 AB, Yerseke, The Netherlands
| | - Gert Flik
- Department of Animal Physiology, Faculty of Science, Institute for Water and Wetland Research, Radboud University Nijmegen, Heyendaalseweg 135, Box 30, 6525 AJ, Nijmegen, The Netherlands.
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Glucose metabolism in fish: a review. J Comp Physiol B 2012; 182:1015-45. [PMID: 22476584 DOI: 10.1007/s00360-012-0658-7] [Citation(s) in RCA: 382] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Revised: 03/06/2012] [Accepted: 03/10/2012] [Indexed: 02/07/2023]
Abstract
Teleost fishes represent a highly diverse group consisting of more than 20,000 species living across all aquatic environments. This group has significant economical, societal and environmental impacts, yet research efforts have concentrated primarily on salmonid and cyprinid species. This review examines carbohydrate/glucose metabolism and its regulation in these model species including the role of hormones and diet. Over the past decade, molecular tools have been used to address some of the downstream components of these processes and these are incorporated to better understand the roles played by carbohydrates and their regulatory paths. Glucose metabolism remains a contentious area as many fish species are traditionally considered glucose intolerant and, therefore, one might expect that the use and storage of glucose would be considered of minor importance. However, the actual picture is not so clear since the apparent intolerance of fish to carbohydrates is not evident in herbivorous and omnivorous species and even in carnivorous species, glucose is important for specific tissues and/or for specific activities. Thus, our aim is to up-date carbohydrate metabolism in fish, placing it to the context of these new experimental tools and its relationship to dietary intake. Finally, we suggest that new research directions ultimately will lead to a better understanding of these processes.
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Glucose and lipid metabolism in the pancreas of rainbow trout is regulated at the molecular level by nutritional status and carbohydrate intake. J Comp Physiol B 2011; 182:507-16. [PMID: 22203338 DOI: 10.1007/s00360-011-0636-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2011] [Revised: 12/08/2011] [Accepted: 12/09/2011] [Indexed: 10/14/2022]
Abstract
Glucose and lipid metabolism in pancreatic islet organs is poorly characterized. In the present study, using as a model the carnivorous rainbow trout, a glucose-intolerant fish, we assessed mRNA expression levels of several genes involved in glucose and lipid metabolism (including ATP-citrate lyase; carnitine palmitoyltransferase-1 isoforms, CPT; the mitochondrial isoform of the phosphoenolpyrutave carboxykinase, mPEPCK and pyruvate kinase, PK) and glucosensing (glucose transporter type 2, Glut2; glucokinase, GK and the potassium channel, K(ATP)) in Brockmann bodies. We evaluated the response of these parameters to changes in feeding status (food deprived vs. fed fish) as well as to changes in the amount of carbohydrate (dextrin) in the diet. A general inhibition of the glycolytic (including the glucosensing marker GK) and β-oxidation pathways was found when comparing fed versus food-deprived fish. When comparing fish feeding on either low- or high-carbohydrate diets, we found that some genes related to lipid metabolism were more controlled by the feeding status than by the carbohydrate content (fatty acid synthase, CPTs). Findings are discussed in the context of pancreatic regulation of glucose and lipid metabolism in fish, and show that while trout pancreatic metabolism can partially adapt to a high-carbohydrate diet, some of the molecular actors studied seem to be poorly regulated (K(ATP)) and may contribute to the glucose intolerance observed in this species when fed high-carbohydrate diets.
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Polakof S, Míguez JM, Soengas JL. Cholecystokinin impact on rainbow trout glucose homeostasis: Possible involvement of central glucosensors. ACTA ACUST UNITED AC 2011; 172:23-9. [DOI: 10.1016/j.regpep.2011.08.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Revised: 07/15/2011] [Accepted: 08/12/2011] [Indexed: 12/15/2022]
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Polakof S, Míguez JM, Soengas JL. Ghrelin effects on central glucosensing and energy homeostasis-related peptides in rainbow trout. Domest Anim Endocrinol 2011; 41:126-36. [PMID: 21798689 DOI: 10.1016/j.domaniend.2011.05.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Revised: 05/22/2011] [Accepted: 05/24/2011] [Indexed: 12/23/2022]
Abstract
Although the role of ghrelin (GHRL) on fish appetite regulation had been widely studied in past years, its involvement in the regulation of glucose metabolism had been little explored. In the present study we hypothesize that GHRL may have a role in the regulation of glucose homeostasis in fish. Therefore, we carried out different experimental approaches in rainbow trout to assess brain glucosensing potential and glucose metabolism in response to GHRL treatment. We found that after either systemic or central GHRL administration to trout deprived of food, glycemia remained unaffected, whereas (in clear contrast with the mammalian model) a consistent activation of the main glucosensing markers (glucose transporter 2, glucokinase, and ATP-sensitive inward rectified K+ channel) was noticed in both hypothalamus and hindbrain. Some of these results were further confirmed by in vitro incubations of hypothalamus and hindbrain in the presence of GHRL. Despite the lack of changes in glycemia, we suggest that the changes elicited by GHRL on the glucosensing system are direct and could be related to a helper action of this hormone when glucose arrived in the postprandial phase. Moreover, we also studied the effect of GHRL treatment on the expression of several food intake-related neuropeptides, such as neuropeptide Y, cocaine- and amphetamine-regulated transcript, pro-opiomelanocortin, and corticotropin-releasing factor. We observed an important variability in the effects of GHRL attributable either to the route of GHRL administration or to the brain regions assessed, which could help explain the contradictory results described in fish literature about GHRL role in food intake control.
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Affiliation(s)
- S Polakof
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, 36310 Vigo, Spain.
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Polakof S, Mommsen TP, Soengas JL. Glucosensing and glucose homeostasis: from fish to mammals. Comp Biochem Physiol B Biochem Mol Biol 2011; 160:123-49. [PMID: 21871969 DOI: 10.1016/j.cbpb.2011.07.006] [Citation(s) in RCA: 169] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2011] [Revised: 07/20/2011] [Accepted: 07/22/2011] [Indexed: 12/16/2022]
Abstract
This review is focused on two topics related to glucose in vertebrates. In a first section devoted to glucose homeostasis we describe how glucose levels fluctuate and are regulated in different classes of vertebrates. The detection of these fluctuations is essential for homeostasis and for other physiological processes such as regulation of food intake. The capacity of that detection is known as glucosensing, and the different mechanisms through which it occurs are known as glucosensors. Different glucosensor mechanisms have been demonstrated in different tissues and organs of rodents and humans whereas the information obtained for other vertebrates is scarce. In the second section of the review we describe the present knowledge regarding glucosensor mechanisms in different groups of vertebrates, with special emphasis in fish.
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Affiliation(s)
- Sergio Polakof
- INRA, UMR, UNH, CRNH Auvergne, Clermont-Ferrand, France.
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Polakof S, Míguez JM, Soengas JL. Evidence for a gut-brain axis used by glucagon-like peptide-1 to elicit hyperglycaemia in fish. J Neuroendocrinol 2011; 23:508-18. [PMID: 21564347 DOI: 10.1111/j.1365-2826.2011.02137.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
In mammals, glucagon-like peptide-1 (GLP-1) produces changes in glucose and energy homeostasis through a gut-pancreas-brain axis. In fish, the effects of GLP-1 are opposed to those described in other vertebrates, such as stimulation of hyperglycaemia and the lack of an effect of incretin. In the present study conducted in a teleost fish such as the rainbow trout, we present evidence of a gut-brain axis used by GLP-1 to exert its actions on glucose and energy homeostasis. We have assessed the effects of GLP-1 on glucose metabolism in the liver as well as the glucose-sensing potential in the hypothalamus and hindbrain. We confirm that peripheral GLP-1 administration elicits sustained hyperglycaemia, whereas, for the first time in a vertebrate species, we report that central GLP-1 treatment increases plasma glucose levels. We have observed (using capsaicin) that at least part of the action of GLP-1 on glucose homeostasis was mediated by vagal and splanchnic afferents. GLP-1 has a direct effect in parameters involved in glucose sensing in the hindbrain, whereas, in the hypothalamus, changes occurred indirectly through hyperglycaemia. Moreover, in the hindbrain, GLP-1 altered the expression of peptides involved in the control of food intake. We have elaborated a model for the actions of GLP-1 in fish in which this peptide uses a mammalian-like ancestral gut-brain axis to elicit the regulation of glucose homeostasis in different manner than the model described in mammals. Finally, it is worth noting that the hyperglycaemia induced by this peptide and the lack of incretin function could be related to the glucose intolerance observed in carnivorous teleost fish species such as the rainbow trout.
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Affiliation(s)
- S Polakof
- Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Funcional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, Vigo, Spain.
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Omlin T, Weber JM. Hypoxia stimulates lactate disposal in rainbow trout. ACTA ACUST UNITED AC 2011; 213:3802-9. [PMID: 21037059 DOI: 10.1242/jeb.048512] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Current understanding of lactate metabolism in fish is based almost entirely on the interpretation of concentration measurements that cannot be used to infer changes in flux. The goals of this investigation were: (1) to quantify baseline lactate fluxes in rainbow trout (Oncorhynchus mykiss) under normoxic conditions; (2) to establish how changes in rates of lactate appearance (R(a)) and disposal (R(d)) account for the increase in blood lactate elicited by hypoxia; and (3) to identify the tissues responsible for lactate production. R(a) and R(d) lactate of rainbow trout were measured in vivo by continuous infusion of [U-(14)C]lactate in trout exposed to 25% O(2) saturation or maintained in normoxia for 90 min. In normoxic fish, R(a) lactate decreased from 18.2 to 13.1 μmol kg(-1) min(-1) and R(d) lactate from 19.0 to 12.8. R(a) and R(d) were always matched, thereby maintaining a steady baseline blood lactate concentration of ∼0.8 mmol l(-1). By contrast, the hypoxic fish increased blood lactate to 8.9 mmol l(-1) and R(a) lactate from 18.4 to 36.5 μmol kg(-1) min(-1). This stimulation of anaerobic glycolysis was unexpectedly accompanied by a 52% increase in R(d) lactate from 19.9 to 30.3 μmol kg(-1) min(-1). White muscle was the main producer of lactate, which accumulated to 19.2 μmol g(-1) in this tissue. This first study of non-steady-state lactate kinetics in fish shows that the increase in lactate disposal elicited by hypoxia plays a strategic role in reducing the lactate load on the circulation. Without this crucial response, blood lactate accumulation would double.
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Affiliation(s)
- Teye Omlin
- Biology Department, University of Ottawa, Ottawa, Ontario, Canada.
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Polakof S, Alvarez R, Soengas JL. Gut glucose metabolism in rainbow trout: implications in glucose homeostasis and glucosensing capacity. Am J Physiol Regul Integr Comp Physiol 2010; 299:R19-32. [PMID: 20357022 DOI: 10.1152/ajpregu.00005.2010] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The main objective of the present study was to evaluate the relative contribution of the intestine to glucose homeostasis in rainbow trout. In a first set of in vivo experiments trout were subjected to oral glucose treatments alone or in combination with insulin injections to assess changes in glucose-related enzymes activities, metabolite levels, and mRNA levels. Rainbow trout gut displays an important glucose metabolism that includes the ability to store glucose as glycogen (mostly in the muscle layers) and a large capacity to oxidize glucose. This constitutes a surprising result for a carnivorous fish. In a second set of in vivo experiments, trout received an oral amino acid solution alone or in combination with insulin injection to determine whether other factors besides fasting could regulate gluconeogenesis in intestine. The results confirm the absence of regulation of gluconeogenesis in trout gut, which does not respond to hormones, glucose, lactate, or amino acid changes, either in vivo or in vitro. We also fully characterized gut glucose metabolism in vitro. We observed that a large amount of glucose is oxidized to lactate, supporting the importance of glucose in gut metabolism. Moreover, we corroborated the minor actions of insulin in trout gut, whereas other hormones such as glucagon-like peptide-1 and C-peptide appear to be major hormonal regulators of glucose metabolism in fish gut. Finally, we obtained the first evidence for the existence of a glucosensing mechanism in the midgut of this carnivorous species.
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Affiliation(s)
- Sergio Polakof
- Laboratorio de Fisioloxía Animal, Facultade de Bioloxía, Edificio de Ciencias Experimentais, Universidade de Vigo, Vigo, Spain.
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Mennigen JA, Harris EA, Chang JP, Moon TW, Trudeau VL. Fluoxetine affects weight gain and expression of feeding peptides in the female goldfish brain. ACTA ACUST UNITED AC 2009; 155:99-104. [DOI: 10.1016/j.regpep.2009.01.001] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2008] [Revised: 01/06/2009] [Accepted: 01/13/2009] [Indexed: 01/16/2023]
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Abstract
PURPOSE OF REVIEW Almost 15 years after its initial proposal, the astrocyte-neuron lactate shuttle hypothesis still occupies the center stage in research on brain energetics. Recent developments have provided further evidence for its validity and have extended its application to different areas of neuroscience. RECENT FINDINGS Description of cell-specific metabolic characteristics have reinforced the view that a prominent conversion of glucose into lactate takes place in astrocytes, whereas neurons preferentially take up and oxidize lactate over glucose-derived pyruvate. Indeed, specific mechanisms are activated by glutamatergic activity to favor such a net lactate transfer between the two cell types. Moreover, demonstration in vivo of the existence and implication of the astrocyte-neuron lactate shuttle hypothesis for particular neurophysiological processes is beginning to appear. SUMMARY Brain energetics has undertaken its revolution. A new concept based on metabolic compartmentalization between astrocytes and neurons is establishing itself as the leading paradigm that opens new perspectives in areas such as functional brain imaging and regulation of energy homeostasis.
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Affiliation(s)
- Luc Pellerin
- Département de Physiologie, Université de Lausanne, Lausanne, Switzerland.
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Polakof S, Soengas JL. Differential effects of in vivo and in vitro lactate treatments on liver carbohydrate metabolism of rainbow trout. Comp Biochem Physiol A Mol Integr Physiol 2008; 151:205-10. [DOI: 10.1016/j.cbpa.2008.06.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2008] [Revised: 06/23/2008] [Accepted: 06/24/2008] [Indexed: 10/21/2022]
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Polakof S, Panserat S, Plagnes-Juan E, Soengas JL. Altered dietary carbohydrates significantly affect gene expression of the major glucosensing components in Brockmann bodies and hypothalamus of rainbow trout. Am J Physiol Regul Integr Comp Physiol 2008; 295:R1077-88. [DOI: 10.1152/ajpregu.90476.2008] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Carnivorous fish have a limited capacity to utilize dietary carbohydrates even though glucosensing components exist in the hypothalamus and Brockmann bodies. Therefore, we fed trout for 10 days with two experimental diets containing a high level of carbohydrates (20%) or a carbohydrate-free level (<0.3%) to test the capacity of dietary carbohydrates to regulate gene expression of glucosensing components. Fish were fed and killed 1, 6, and 24 h after the meal to analyze plasma glucose levels, glucosensing-related biochemical parameters, and gene expression of the major components of the glucosensing system in the hypothalamus and Brockmann bodies. Glucose facilitative transporter type 2 and glucokinase gene expression were confirmed by real-time PCR data and two new components of the glucosensing mechanism, Kir6.-like and sulfonylurea receptor-like, were detected for the first time in fish in both tissues. In addition, a clear adaptation to dietary carbohydrates was found in trout Brockmann bodies, based on increased gene expression of major components of the system as well as enhanced glucokinase activities and glycogen levels. In contrast, in the hypothalamus, only glucokinase gene expression and activity showed a response to dietary carbohydrates, supporting the key role of that enzyme in glucosensing mechanism. Finally, a differential postprandial profile was found between tissues regarding the glucosensing potential, since the hypothalamus seems to respond to hyperglycemia earlier than the Brockmann bodies, whose response took place later. Altogether, these data describe for the first time in fish a complete response of major glucosensing components to dietary carbohydrates in trout hypothalamus and Brockmann bodies, supporting an efficient adaptation of both tissues to those dietary components.
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