Impact of long-term fasting on the stomach-hypothalamus appetite regulating genes in Atlantic salmon postsmolts
Atlantic salmon will experience periods of fasting during its lifecycle. In nature, prolonged fasting periods occur owing to seasonal fluctuations in available feeds, migration or in relation to reproduction. In a culture setting, salmon is fasted mainly as part of planned operational handling prior...
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Online Access: | https://hdl.handle.net/11250/3083260 https://doi.org/10.1016/j.aquaculture.2022.738917 |
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ftunivbergen:oai:bora.uib.no:11250/3083260 2023-09-05T13:18:10+02:00 Impact of long-term fasting on the stomach-hypothalamus appetite regulating genes in Atlantic salmon postsmolts Kalananthan, Tharmini Folkedal, Ole Gomes, Ana S. Lai, Floriana Handeland, Sigurd Olav Tolås, Ingvill Gelebart, Virginie Rønnestad, Ivar 2023 application/pdf https://hdl.handle.net/11250/3083260 https://doi.org/10.1016/j.aquaculture.2022.738917 eng eng Elsevier urn:issn:0044-8486 https://hdl.handle.net/11250/3083260 https://doi.org/10.1016/j.aquaculture.2022.738917 cristin:2067601 Aquaculture. 2023, 563, Part 2, 738917. Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no Copyright 2022 The Authors 738917 Aquaculture 563 Part 2 Journal article Peer reviewed 2023 ftunivbergen https://doi.org/10.1016/j.aquaculture.2022.738917 2023-08-16T23:07:22Z Atlantic salmon will experience periods of fasting during its lifecycle. In nature, prolonged fasting periods occur owing to seasonal fluctuations in available feeds, migration or in relation to reproduction. In a culture setting, salmon is fasted mainly as part of planned operational handling prior to vaccination, delousing, transfer etc., and where fasting may last up to nine days. The mechanisms regulating the appetite during long-term fasting may vary among fish species. Here, we studied the impact of long-term fasting on neuro-endocrine regulation of appetite through the stomach-hypothalamic axis in Atlantic salmon post smolts (1.2 kg, ∼46 cm), reared in two experimental conditions (Fed and Fasted; triplicated tanks), and sampled after 4 weeks and 6 weeks of fasting. Fasted fish showed lower condition factor and hepatosomatic index at both sampling points compared to Fed group. In qPCR analysis, hypothalamic relative mRNA expression of agouti-related protein 1 (agrp1) was upregulated in fasted group at both sampling points. Among neuropeptide Y (npy) paralogs, only npya1 at 4 weeks was upregulated by fasting. As for cocaine- and amphetamine-regulated transcripts (cart), cart2a was elevated at 4 weeks, and cart2b at both 4 and 6 weeks in fasted group, while cart3a and cart4 showed no response to fasting. The pro-opiomelanocortin (pomc) a1, a2 and melanocortin-4 receptor (mc4r) a2 increased only after 6 weeks of fasting, while mc4rb1 did not respond to fasting. In stomach, 6 weeks of fasting resulted in a decrease of ghrelin1 (ghrl1), while expression of mboat4 was unaffected. The elevated levels of hypothalamic agrp1 and npya1 in fasted group support orexigenic roles for these neuropeptides. In addition, upregulation of cart2a, cart2b, pomca1 and pomca2 indicate that these play vital roles in appetite regulation and that fasting may halt and/or counteract hunger signals (agrp1 and npya1) to save energy from foraging search activities during catabolic conditions. Another possibility is that these ... Article in Journal/Newspaper Atlantic salmon University of Bergen: Bergen Open Research Archive (BORA-UiB) Aquaculture 563 738917 |
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Open Polar |
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University of Bergen: Bergen Open Research Archive (BORA-UiB) |
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ftunivbergen |
language |
English |
description |
Atlantic salmon will experience periods of fasting during its lifecycle. In nature, prolonged fasting periods occur owing to seasonal fluctuations in available feeds, migration or in relation to reproduction. In a culture setting, salmon is fasted mainly as part of planned operational handling prior to vaccination, delousing, transfer etc., and where fasting may last up to nine days. The mechanisms regulating the appetite during long-term fasting may vary among fish species. Here, we studied the impact of long-term fasting on neuro-endocrine regulation of appetite through the stomach-hypothalamic axis in Atlantic salmon post smolts (1.2 kg, ∼46 cm), reared in two experimental conditions (Fed and Fasted; triplicated tanks), and sampled after 4 weeks and 6 weeks of fasting. Fasted fish showed lower condition factor and hepatosomatic index at both sampling points compared to Fed group. In qPCR analysis, hypothalamic relative mRNA expression of agouti-related protein 1 (agrp1) was upregulated in fasted group at both sampling points. Among neuropeptide Y (npy) paralogs, only npya1 at 4 weeks was upregulated by fasting. As for cocaine- and amphetamine-regulated transcripts (cart), cart2a was elevated at 4 weeks, and cart2b at both 4 and 6 weeks in fasted group, while cart3a and cart4 showed no response to fasting. The pro-opiomelanocortin (pomc) a1, a2 and melanocortin-4 receptor (mc4r) a2 increased only after 6 weeks of fasting, while mc4rb1 did not respond to fasting. In stomach, 6 weeks of fasting resulted in a decrease of ghrelin1 (ghrl1), while expression of mboat4 was unaffected. The elevated levels of hypothalamic agrp1 and npya1 in fasted group support orexigenic roles for these neuropeptides. In addition, upregulation of cart2a, cart2b, pomca1 and pomca2 indicate that these play vital roles in appetite regulation and that fasting may halt and/or counteract hunger signals (agrp1 and npya1) to save energy from foraging search activities during catabolic conditions. Another possibility is that these ... |
format |
Article in Journal/Newspaper |
author |
Kalananthan, Tharmini Folkedal, Ole Gomes, Ana S. Lai, Floriana Handeland, Sigurd Olav Tolås, Ingvill Gelebart, Virginie Rønnestad, Ivar |
spellingShingle |
Kalananthan, Tharmini Folkedal, Ole Gomes, Ana S. Lai, Floriana Handeland, Sigurd Olav Tolås, Ingvill Gelebart, Virginie Rønnestad, Ivar Impact of long-term fasting on the stomach-hypothalamus appetite regulating genes in Atlantic salmon postsmolts |
author_facet |
Kalananthan, Tharmini Folkedal, Ole Gomes, Ana S. Lai, Floriana Handeland, Sigurd Olav Tolås, Ingvill Gelebart, Virginie Rønnestad, Ivar |
author_sort |
Kalananthan, Tharmini |
title |
Impact of long-term fasting on the stomach-hypothalamus appetite regulating genes in Atlantic salmon postsmolts |
title_short |
Impact of long-term fasting on the stomach-hypothalamus appetite regulating genes in Atlantic salmon postsmolts |
title_full |
Impact of long-term fasting on the stomach-hypothalamus appetite regulating genes in Atlantic salmon postsmolts |
title_fullStr |
Impact of long-term fasting on the stomach-hypothalamus appetite regulating genes in Atlantic salmon postsmolts |
title_full_unstemmed |
Impact of long-term fasting on the stomach-hypothalamus appetite regulating genes in Atlantic salmon postsmolts |
title_sort |
impact of long-term fasting on the stomach-hypothalamus appetite regulating genes in atlantic salmon postsmolts |
publisher |
Elsevier |
publishDate |
2023 |
url |
https://hdl.handle.net/11250/3083260 https://doi.org/10.1016/j.aquaculture.2022.738917 |
genre |
Atlantic salmon |
genre_facet |
Atlantic salmon |
op_source |
738917 Aquaculture 563 Part 2 |
op_relation |
urn:issn:0044-8486 https://hdl.handle.net/11250/3083260 https://doi.org/10.1016/j.aquaculture.2022.738917 cristin:2067601 Aquaculture. 2023, 563, Part 2, 738917. |
op_rights |
Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no Copyright 2022 The Authors |
op_doi |
https://doi.org/10.1016/j.aquaculture.2022.738917 |
container_title |
Aquaculture |
container_volume |
563 |
container_start_page |
738917 |
_version_ |
1776199199319130112 |