Pub Date : 2024-05-16DOI: 10.1016/j.cbpa.2024.111665
Nemo E. Buchmiller, Savannah J. Weaver , Robin E. Bedard, Emily N. Taylor, Haley A. Moniz
As climate change alters the hydric regime of many habitats, understanding the hydric physiology of animals becomes increasingly important. Plasma osmolality is a popular metric to assess an organism's hydration, but samples often need to be stored before being analyzed, under varying conditions and for different lengths of time. Previous studies on plasma storage conditions, and how they impact sample integrity, are minimal and have focused more on clinical applications than field studies. We studied the stability of osmolality values from wild rattlesnake plasma samples stored in commonly used plastic snap-cap tubes under different time (0, 2, 3, 7, 29 days) and temperature (refrigerated at 2 °C and frozen at −18 °C) treatments. We hypothesized that frozen samples would remain more stable (e.g., retain osmolality values more similar to baseline values) than refrigerated samples because freezing the plasma would reduce evaporation. We found that osmolality of samples increased over time at both temperatures, becoming significantly higher than baseline after 7 days. Contrary to our prediction, osmolality increased more in frozen samples than in refrigerated samples. We discuss possible reasons for our results, along with their implications. To obtain the most accurate plasma osmolality values, we recommend refrigerating plasma samples for as short a time as possible, 3 days or fewer, before analyzing them on an osmometer.
{"title":"Short communication: Storage time and temperature affect plasma osmolality values in field-collected blood samples","authors":"Nemo E. Buchmiller, Savannah J. Weaver , Robin E. Bedard, Emily N. Taylor, Haley A. Moniz","doi":"10.1016/j.cbpa.2024.111665","DOIUrl":"10.1016/j.cbpa.2024.111665","url":null,"abstract":"<div><p>As climate change alters the hydric regime of many habitats, understanding the hydric physiology of animals becomes increasingly important. Plasma osmolality is a popular metric to assess an organism's hydration, but samples often need to be stored before being analyzed, under varying conditions and for different lengths of time. Previous studies on plasma storage conditions, and how they impact sample integrity, are minimal and have focused more on clinical applications than field studies. We studied the stability of osmolality values from wild rattlesnake plasma samples stored in commonly used plastic snap-cap tubes under different time (0, 2, 3, 7, 29 days) and temperature (refrigerated at 2 °C and frozen at −18 °C) treatments. We hypothesized that frozen samples would remain more stable (e.g., retain osmolality values more similar to baseline values) than refrigerated samples because freezing the plasma would reduce evaporation. We found that osmolality of samples increased over time at both temperatures, becoming significantly higher than baseline after 7 days. Contrary to our prediction, osmolality increased more in frozen samples than in refrigerated samples. We discuss possible reasons for our results, along with their implications. To obtain the most accurate plasma osmolality values, we recommend refrigerating plasma samples for as short a time as possible, 3 days or fewer, before analyzing them on an osmometer.</p></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140961010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-10DOI: 10.1016/j.cbpa.2024.111664
Giuliam K. Strücker , Michael L. Jaramillo , Thaline de Quadros, Evelise M. Nazari
Aquatic environments are subject to ultraviolet B (UVB) radiation incidence, and its effects on organisms are dose-dependent. Besides DNA, mitochondria are an important target of this radiation that causes structural damage and impairs its functional dynamics. Here, we hypothesize that mitophagy acts as an organelle quality control mechanism to mitigate UVB impacts in embryonic cells. Then, freshwater prawn Macrobrachium olfersii embryos was used as a model to investigate the effects of UVB on genes (Tomm20, Opa1, Pink, Prkn, Sqstm1, and Map1lc3) and proteins (TOM20, PINK1, p62 and LC3B) involved in mitophagy modulation. The choice of genes and proteins was based on the identification of mitochondrial membrane (Tomm20, Opa1 and TOM20), mediation of mitophagy (Pink1, Prkn and PINK1), and recognition of mitochondria by the autophagosome membrane (Sqstm1, Map1lc3, p62 and LC3B). First, the phylogeny of all genes presented bootstrap values >80 and conserved domains among crustacean species. Gene expression was inherently modulated during development, with transcripts (Tomm20, Opa1, Pink, Prkn, Sqstm1, and Map1lc3) overexpressed in the initial and final stages of development. Moreover, UVB radiation induced upregulation of Tomm20, Opa1, Pink, Prkn, Sqstm1, and Map1lc3 genes at 6 h after exposure. Interestingly, after 12 h, the protein content of PINK1, p62, and LC3B increased, while TOM20 was not responsive. Despite UVB radiation's harmful effects on embryonic cells, the chronology of gene expression and protein content indicates rapid activation of mitophagy, serving as an organelle quality control mechanism, given the analyzed cells' integrity.
{"title":"UVB radiation exposure modulates mitophagy in embryonic cells of freshwater prawn Macrobrachium olfersii: Exploring a protective organelle quality control mechanism","authors":"Giuliam K. Strücker , Michael L. Jaramillo , Thaline de Quadros, Evelise M. Nazari","doi":"10.1016/j.cbpa.2024.111664","DOIUrl":"10.1016/j.cbpa.2024.111664","url":null,"abstract":"<div><p>Aquatic environments are subject to ultraviolet B (UVB) radiation incidence, and its effects on organisms are dose-dependent. Besides DNA, mitochondria are an important target of this radiation that causes structural damage and impairs its functional dynamics. Here, we hypothesize that mitophagy acts as an organelle quality control mechanism to mitigate UVB impacts in embryonic cells. Then, freshwater prawn <em>Macrobrachium olfersii</em> embryos was used as a model to investigate the effects of UVB on genes (<em>Tomm20</em>, <em>Opa1</em>, <em>Pink</em>, <em>Prkn</em>, <em>Sqstm1</em>, and <em>Map1lc3</em>) and proteins (TOM20, PINK1, p62 and LC3B) involved in mitophagy modulation. The choice of genes and proteins was based on the identification of mitochondrial membrane (<em>Tomm20</em>, <em>Opa1</em> and TOM20), mediation of mitophagy (<em>Pink1</em>, <em>Prkn</em> and PINK1), and recognition of mitochondria by the autophagosome membrane (<em>Sqstm1</em>, <em>Map1lc3</em>, p62 and LC3B). First, the phylogeny of all genes presented bootstrap values >80 and conserved domains among crustacean species. Gene expression was inherently modulated during development, with transcripts (<em>Tomm20</em>, <em>Opa1</em>, <em>Pink</em>, <em>Prkn</em>, <em>Sqstm1</em>, and <em>Map1lc3</em>) overexpressed in the initial and final stages of development. Moreover, UVB radiation induced upregulation of <em>Tomm20</em>, <em>Opa1</em>, <em>Pink</em>, <em>Prkn</em>, <em>Sqstm1</em>, and <em>Map1lc3</em> genes at 6 h after exposure. Interestingly, after 12 h, the protein content of PINK1, p62, and LC3B increased, while TOM20 was not responsive. Despite UVB radiation's harmful effects on embryonic cells, the chronology of gene expression and protein content indicates rapid activation of mitophagy, serving as an organelle quality control mechanism, given the analyzed cells' integrity.</p></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140913421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-10DOI: 10.1016/j.cbpa.2024.111663
Takafumi Kodama , Seiya Watanabe , Isana Kayanuma , Akira Sasaki , Daisuke Kurokawa , Otto Baba , Mitsuru Jimbo , Fumiya Furukawa
During the development of teleost fish, the sole nutrient source is the egg yolk. The yolk consists mostly of proteins and lipids, with only trace amounts of carbohydrates such as glycogen and glucose. However, past evidence in some fishes showed transient increase in glucose during development, which may have supported the development of the embryos. Recently, we found in zebrafish that the yolk syncytial layer (YSL), an extraembryonic tissue surrounding the yolk, undergoes gluconeogenesis. However, in other teleost species, the knowledge on such gluconeogenic functions during early development is lacking. In this study, we used a marine fish, the grass puffer (Takifugu niphobles) and assessed possible gluconeogenic functions of their YSL, to understand the difference or shared features of gluconeogenesis between these species. A liquid chromatography (LC) / mass spectrometry (MS) analysis revealed that glucose and glycogen content significantly increased in the grass puffer during development. Subsequent real-time PCR results showed that most of the genes involved in gluconeogenesis increased in segmentation stages and/or during hatching. Among these genes, many were expressed in the YSL and liver, as shown by in situ hybridization analysis. In addition, glycogen immunostaining revealed that this carbohydrate source was accumulated in many tissues at segmentation stage but exclusively in the liver in hatched individuals. Taken together, these results suggest that developing grass puffer undergoes gluconeogenesis and glycogen synthesis during development, and that gluconeogenic activity is shared in YSL of zebrafish and grass puffer.
{"title":"Gluconeogenesis during development of the grass puffer (Takifugu niphobles)","authors":"Takafumi Kodama , Seiya Watanabe , Isana Kayanuma , Akira Sasaki , Daisuke Kurokawa , Otto Baba , Mitsuru Jimbo , Fumiya Furukawa","doi":"10.1016/j.cbpa.2024.111663","DOIUrl":"10.1016/j.cbpa.2024.111663","url":null,"abstract":"<div><p>During the development of teleost fish, the sole nutrient source is the egg yolk. The yolk consists mostly of proteins and lipids, with only trace amounts of carbohydrates such as glycogen and glucose. However, past evidence in some fishes showed transient increase in glucose during development, which may have supported the development of the embryos. Recently, we found in zebrafish that the yolk syncytial layer (YSL), an extraembryonic tissue surrounding the yolk, undergoes gluconeogenesis. However, in other teleost species, the knowledge on such gluconeogenic functions during early development is lacking. In this study, we used a marine fish, the grass puffer (<em>Takifugu niphobles</em>) and assessed possible gluconeogenic functions of their YSL, to understand the difference or shared features of gluconeogenesis between these species. A liquid chromatography (LC) / mass spectrometry (MS) analysis revealed that glucose and glycogen content significantly increased in the grass puffer during development. Subsequent real-time PCR results showed that most of the genes involved in gluconeogenesis increased in segmentation stages and/or during hatching. Among these genes, many were expressed in the YSL and liver, as shown by <em>in situ</em> hybridization analysis. In addition, glycogen immunostaining revealed that this carbohydrate source was accumulated in many tissues at segmentation stage but exclusively in the liver in hatched individuals. Taken together, these results suggest that developing grass puffer undergoes gluconeogenesis and glycogen synthesis during development, and that gluconeogenic activity is shared in YSL of zebrafish and grass puffer.</p></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140913420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-08DOI: 10.1016/j.cbpa.2024.111654
Antônio V.G.S. Neto, Renato Filogonio, Cléo A.C. Leite
The time course for recovery after anesthesia is poorly described for tricaine methanesulfonate (MS-222). We suggest that the baroreflex and the heart rate variability (HRV) could be used to index the recovery of the autonomic modulation after anesthesia. We analyzed the recovery profile of behavioral and physiological parameters over time to analyze the progression of recovery after anesthesia of American bullfrogs with MS-222. Mean heart rate stabilized after 17 h, whereas the baroreflex efficiency index took 23 h and the baroreflex operating gain, 29 h. Mean arterial pressure recovered after 26 h. Power spectral density peaked at 23 h and again after 40 h. Baroreflex was a relevant component of the first phase of HRV, while autonomic modulation for resting may take longer than 40 h. We suggest that physiological recovery is a complex phenomenon with multiple progressive phases, and the baroreflex may be a useful tool to observe the first substantial recovery of post-instrumentation capacity for autonomic modulation.
{"title":"Recovery of the baroreflex and autonomic modulation after anesthesia with MS-222 in bullfrogs","authors":"Antônio V.G.S. Neto, Renato Filogonio, Cléo A.C. Leite","doi":"10.1016/j.cbpa.2024.111654","DOIUrl":"10.1016/j.cbpa.2024.111654","url":null,"abstract":"<div><p>The time course for recovery after anesthesia is poorly described for tricaine methanesulfonate (MS-222). We suggest that the baroreflex and the heart rate variability (HRV) could be used to index the recovery of the autonomic modulation after anesthesia. We analyzed the recovery profile of behavioral and physiological parameters over time to analyze the progression of recovery after anesthesia of American bullfrogs with MS-222. Mean heart rate stabilized after 17 h, whereas the baroreflex efficiency index took 23 h and the baroreflex operating gain, 29 h. Mean arterial pressure recovered after 26 h. Power spectral density peaked at 23 h and again after 40 h. Baroreflex was a relevant component of the first phase of HRV, while autonomic modulation for resting may take longer than 40 h. We suggest that physiological recovery is a complex phenomenon with multiple progressive phases, and the baroreflex may be a useful tool to observe the first substantial recovery of post-instrumentation capacity for autonomic modulation.</p></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140905082","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-07DOI: 10.1016/j.cbpa.2024.111655
Enkhbat Undrakhbayar , Xue-Ying Zhang , Chen-Zhu Wang , De-Hua Wang
Ambient temperatures have great impacts on thermoregulation of small mammals. Brown adipose tissue (BAT), an obligative thermogenic tissue for small mammals, is localized not only in the interscapular depot (iBAT), but also in supraclavicular, infra/subscapular, cervical, paravertebral, and periaortic depots. The iBAT is known for its cold-induced thermogenesis, however, less has been paid attention to the function of BAT at other sites. Here, we investigated the function of BAT at different sites of the body during cold acclimation in a small rodent species. As expected, Brandt's voles (Lasiopodomys brandtii) consumed more food and reduced the body mass gain when they were exposed to cold. The voles increased resting metabolic rate and maintained a relatively lower body temperature in the cold (36.5 ± 0.27 °C) compared to those in the warm condition (37.1 ± 0.36 °C). During cold acclimation, the uncoupling protein 1 (UCP1) increased in aBAT (axillary), cBAT (anterior cervical), iBAT (interscapular), nBAT (supraclavicular), and sBAT (suprascapular). The levels of proliferating cell nuclear antigen (PCNA), a marker for cell proliferation, were higher in cBAT and iBAT in the cold than in the warm group. The pAMPK/AMPK and pCREB/CREB were increased in cBAT and iBAT during cold acclimation, respectively. These data indicate that these different sites of BAT play the cold-induced thermogenic function for small mammals.
{"title":"The function of brown adipose tissue at different sites of the body in Brandt's voles during cold acclimation","authors":"Enkhbat Undrakhbayar , Xue-Ying Zhang , Chen-Zhu Wang , De-Hua Wang","doi":"10.1016/j.cbpa.2024.111655","DOIUrl":"10.1016/j.cbpa.2024.111655","url":null,"abstract":"<div><p>Ambient temperatures have great impacts on thermoregulation of small mammals. Brown adipose tissue (BAT), an obligative thermogenic tissue for small mammals, is localized not only in the interscapular depot (iBAT), but also in supraclavicular, infra/subscapular, cervical, paravertebral, and periaortic depots. The iBAT is known for its cold-induced thermogenesis, however, less has been paid attention to the function of BAT at other sites. Here, we investigated the function of BAT at different sites of the body during cold acclimation in a small rodent species. As expected, Brandt's voles (<em>Lasiopodomys brandtii</em>) consumed more food and reduced the body mass gain when they were exposed to cold. The voles increased resting metabolic rate and maintained a relatively lower body temperature in the cold (36.5 ± 0.27 °C) compared to those in the warm condition (37.1 ± 0.36 °C). During cold acclimation, the uncoupling protein 1 (UCP1) increased in aBAT (axillary), cBAT (anterior cervical), iBAT (interscapular), nBAT (supraclavicular), and sBAT (suprascapular). The levels of proliferating cell nuclear antigen (PCNA), a marker for cell proliferation, were higher in cBAT and iBAT in the cold than in the warm group. The pAMPK/AMPK and pCREB/CREB were increased in cBAT and iBAT during cold acclimation, respectively. These data indicate that these different sites of BAT play the cold-induced thermogenic function for small mammals.</p></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140898445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-06DOI: 10.1016/j.cbpa.2024.111650
Keiron P.P. Fraser , Lloyd S. Peck , Melody S. Clark , Andrew Clarke
The affect of temperature on tissue protein synthesis rates has been reported in temperate and tropical, but not Antarctic fishes. Previous studies have generally demonstrated low growth rates in Antarctic fish species in comparison to temperate relatives and elevated levels of protein turnover. This study investigates how low temperatures effect tissue protein synthesis and hence tissue growth in a polar fish species. Groups of Antarctic, Harpagifer antarcticus and temperate, Lipophrys pholis, were acclimated to a range of overlapping water temperatures and protein synthesis was measure in white muscle (WM), liver and gastrointestinal tract (GIT). WM protein synthesis rates increased linearly with temperature in both species (H. antarcticus 0.16–0.23%.d−1, L. pholis, 0.31–0.76%.d−1), while liver (H. antarcticus 0.24–0.27%.d−1, L. pholis, 0.44–1.03%.d−1) and GIT were unaffected by temperature in H. antarcticus but increased non-linearly in L.pholis (H. antarcticus 0.22–0.26%.d−1, L. pholis, 0.40–0.86%.d−1). RNA to protein ratios were unaffected by temperature in H. antarcticus but increased weakly, in L.pholis WM and liver. In L.pholis, RNA translational efficiency increased significantly with temperature in all tissues, but only in liver in H. antarcticus. At the overlapping temperature of 3 °C, protein synthesis (WM 26%, Liver, 39%, GIT, 35%) and RNA translational efficiency (WM 273%, Liver, 271%, GIT, 300%) were significantly lower in H. antarcticus than L.pholis, while RNA to protein ratios were significantly higher (WM 270%, Liver 170%, GIT 186%). Tissue specific effects of temperature are detectable in both species. This study provides the first evidence, that tissue protein synthesis rates are constrained in Antarctic fishes.
温度对组织蛋白质合成率的影响在温带和热带鱼类中有报道,但在南极鱼类中没有。以往的研究普遍表明,与温带鱼类相比,南极鱼类的生长率较低,蛋白质周转水平较高。本研究调查了低温如何影响极地鱼类的组织蛋白质合成,进而影响组织生长。将一组南极鱼(Harpagifer antarcticus)和温带鱼(Lipophrys pholis)置于一系列重叠的水温下,测量白肌(WM)、肝脏和胃肠道(GIT)的蛋白质合成。两个物种的白肌蛋白质合成率均随温度的升高而线性增加(H. antarcticus 0.16-0.23%.d-1,L. pholis 0.31-0.76%.d-1),而肝脏(H. antarcticus 0.24-0.27%.d-1,L. pholis 0.44-1%.d-1)的蛋白质合成率则随温度的升高而线性增加。pholis,0.44-1.03%.d-1)和消化道不受温度影响,但在 L. pholis 中则非线性增加(H. antarcticus 0.22-0.26%.d-1,L. pholis,0.40-0.86%.d-1)。在 H. antarcticus 中,RNA 与蛋白质的比率不受温度影响,但在 L. pholis 的 WM 和肝脏中,RNA 与蛋白质的比率增加较弱。在 L. pholis 的所有组织中,RNA 的翻译效率随温度的升高而显著增加,但在 H. antarcticus 中,只有肝脏的翻译效率随温度的升高而显著增加。在 3 °C 的重叠温度下,南极海蛇的蛋白质合成(WM 26%,肝脏 39%,胃肠道 35%)和 RNA 翻译效率(WM 273%,肝脏 271%,胃肠道 300%)明显低于北极海蛇,而 RNA 与蛋白质的比率则明显高于北极海蛇(WM 270%,肝脏 170%,胃肠道 186%)。在这两个物种中都能检测到温度对特定组织的影响。这项研究首次证明南极鱼类的组织蛋白质合成率受到限制。
{"title":"A comparative study of tissue protein synthesis rates in an Antarctic, Harpagifer antarcticus and a temperate, Lipophrys pholis teleost","authors":"Keiron P.P. Fraser , Lloyd S. Peck , Melody S. Clark , Andrew Clarke","doi":"10.1016/j.cbpa.2024.111650","DOIUrl":"10.1016/j.cbpa.2024.111650","url":null,"abstract":"<div><p>The affect of temperature on tissue protein synthesis rates has been reported in temperate and tropical, but not Antarctic fishes. Previous studies have generally demonstrated low growth rates in Antarctic fish species in comparison to temperate relatives and elevated levels of protein turnover. This study investigates how low temperatures effect tissue protein synthesis and hence tissue growth in a polar fish species. Groups of Antarctic, <em>Harpagifer antarcticus</em> and temperate, <em>Lipophrys pholis</em>, were acclimated to a range of overlapping water temperatures and protein synthesis was measure in white muscle (WM), liver and gastrointestinal tract (GIT). WM protein synthesis rates increased linearly with temperature in both species (<em>H. antarcticus</em> 0.16–0.23%.d<sup>−1</sup>, <em>L. pholis</em>, 0.31–0.76%.d<sup>−1</sup>), while liver (<em>H. antarcticus</em> 0.24–0.27%.d<sup>−1</sup>, <em>L. pholis</em>, 0.44–1.03%.d<sup>−1</sup>) and GIT were unaffected by temperature in <em>H. antarcticus</em> but increased non-linearly in <em>L.</em> <em>pholis</em> (<em>H. antarcticus</em> 0.22–0.26%.d<sup>−1</sup>, <em>L. pholis</em>, 0.40–0.86%.d<sup>−1</sup>). RNA to protein ratios were unaffected by temperature in <em>H. antarcticus</em> but increased weakly, in <em>L.</em> <em>pholis</em> WM and liver. In <em>L.</em> <em>pholis</em>, RNA translational efficiency increased significantly with temperature in all tissues, but only in liver in <em>H. antarcticus</em>. At the overlapping temperature of 3 °C, protein synthesis (WM 26%, Liver, 39%, GIT, 35%) and RNA translational efficiency (WM 273%, Liver, 271%, GIT, 300%) were significantly lower in <em>H. antarcticus</em> than <em>L.</em> <em>pholis</em>, while RNA to protein ratios were significantly higher (WM 270%, Liver 170%, GIT 186%). Tissue specific effects of temperature are detectable in both species. This study provides the first evidence, that tissue protein synthesis rates are constrained in Antarctic fishes.</p></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1095643324000771/pdfft?md5=5764dea6ca5fd775defc779c50d80936&pid=1-s2.0-S1095643324000771-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140892954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-05DOI: 10.1016/j.cbpa.2024.111653
Diana R. Barajas-Sandoval , Cristina Escobedo-Fregoso , Eduardo Quiroz-Guzmán , Dariel Tovar-Ramírez , Clara Adèle Py , Alberto Peña-Rodríguez
The present study evaluated the effect of temporal periods of hypothermia and hyperthermia, followed by an optimal temperature recovery phase on the growth, survival, and physiological response of Penaeus vannamei. Post-larvae were exposed to stress periods for 7 and 14 days at 22 °C and 32 °C each, followed by a recovery phase at 28 °C to complete seven experimental weeks, and were compared with a control group maintained at 28 °C. Weight gain, specific growth rate, feed intake, feed conversion ratio, and survival were weekly determined. Muscle, hepatopancreas, and hemolymph were sampled on the 14th day of the recovery phase for biochemical composition, and antioxidant and digestive enzyme activities determination. The shrimp presented a higher growth rate during short-term hyperthermia in contrast to shrimp under hypothermia that presented compensatory growth after thermal stress when the temperature was restored at 28 °C. Hyperthermia increased 12–13% the feed intake while this was diminished 21–29% by the hypothermia periods. Shrimp undergo metabolic adjustments following thermal stress, with short hypothermia increasing the lipase activity and lipid storage in the hepatopancreas, while short hyperthermia also enhances chymotrypsin activity and leads to higher protein and lipid accumulation. Conversely, prolonged hyperthermia induces greater energy consumption, depleting lipid and glycogen stores, while hypothermia causes scarce mobilization of energy reserves during recovery phase. Antioxidant enzyme activities were not affected by short-thermal stress (7d), while prolonged thermal stress (14d) significantly affected SOD, CAT, and GPx activities. The present study provides important insights into the physiological plasticity of P. vannamei during recovery from thermal stress.
{"title":"Effect of temporal thermal stress on Penaeus vannamei: Growth performance and physiological plasticity.","authors":"Diana R. Barajas-Sandoval , Cristina Escobedo-Fregoso , Eduardo Quiroz-Guzmán , Dariel Tovar-Ramírez , Clara Adèle Py , Alberto Peña-Rodríguez","doi":"10.1016/j.cbpa.2024.111653","DOIUrl":"10.1016/j.cbpa.2024.111653","url":null,"abstract":"<div><p>The present study evaluated the effect of temporal periods of hypothermia and hyperthermia, followed by an optimal temperature recovery phase on the growth, survival, and physiological response of <em>Penaeus vannamei</em>. Post-larvae were exposed to stress periods for 7 and 14 days at 22 °C and 32 °C each, followed by a recovery phase at 28 °C to complete seven experimental weeks, and were compared with a control group maintained at 28 °C. Weight gain, specific growth rate, feed intake, feed conversion ratio, and survival were weekly determined. Muscle, hepatopancreas, and hemolymph were sampled on the 14th day of the recovery phase for biochemical composition, and antioxidant and digestive enzyme activities determination. The shrimp presented a higher growth rate during short-term hyperthermia in contrast to shrimp under hypothermia that presented compensatory growth after thermal stress when the temperature was restored at 28 °C. Hyperthermia increased 12–13% the feed intake while this was diminished 21–29% by the hypothermia periods. Shrimp undergo metabolic adjustments following thermal stress, with short hypothermia increasing the lipase activity and lipid storage in the hepatopancreas, while short hyperthermia also enhances chymotrypsin activity and leads to higher protein and lipid accumulation. Conversely, prolonged hyperthermia induces greater energy consumption, depleting lipid and glycogen stores, while hypothermia causes scarce mobilization of energy reserves during recovery phase. Antioxidant enzyme activities were not affected by short-thermal stress (7d), while prolonged thermal stress (14d) significantly affected SOD, CAT, and GPx activities. The present study provides important insights into the physiological plasticity of <em>P. vannamei</em> during recovery from thermal stress.</p></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140877917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-03DOI: 10.1016/j.cbpa.2024.111652
Cheng Fu, Ke-Ying Zhou, Yue Hu, Yong-Fei Zhang, Shi-Jian Fu
Heated effluent injection, cold hypolimnetic water inputs from dams, and extreme weather events can lead to unpredictable temperature fluctuations in natural waters, impacting fish performance and fitness. We hypothesized that fish exposed to such unpredictable fluctuations would exhibit weaker growth and enhanced thermal tolerance compared to predictable conditions. Qingbo (Spinibarbus sinensis) was selected as the experimental subject in this study. The qingbo were divided into a constant temperature group (C, 22 ± 0.5 °C), a predictable temperature fluctuation group (PF, 22 ± 4 °C, first warming, then cooling within a day) and an unpredictable temperature fluctuation group (UF, 22 ± 4 °C, the order of warming or cooling is random). After 40 days of temperature acclimation, the growth, metabolic rate, spontaneous activity, thermal tolerance, plasma cortisol concentration and liver hsp70 level of the fish were measured. Unexpectedly, neither the PF nor the UF group showed decreased growth compared to the C group. This could be attributed to the fact that temperature variation did not lead to a substantial increase in basic energy expenditure. Furthermore, feeding rates increased due to temperature fluctuations, although the difference was not significant. Both the PF and UF groups exhibited increased upper thermal tolerance, but only the UF group exhibited improved lower thermal tolerance and higher liver hsp70 levels compared to the C group. The qingbo that experienced unpredictable temperature fluctuations had the best thermal tolerance among the 3 groups, which might have occurred because they had the highest level of hsp70 expression. This may safeguard fish against the potential lethal consequences of extreme temperatures in the future. These findings suggested that qingbo exhibited excellent adaptability to both predictable and unpredictable temperature fluctuations, which may be associated with frequent temperature fluctuations in its natural habitat.
{"title":"The effects of the predictability of acclimatory temperature on the growth and thermal tolerance of juvenile Spinibarbus sinensis","authors":"Cheng Fu, Ke-Ying Zhou, Yue Hu, Yong-Fei Zhang, Shi-Jian Fu","doi":"10.1016/j.cbpa.2024.111652","DOIUrl":"10.1016/j.cbpa.2024.111652","url":null,"abstract":"<div><p>Heated effluent injection, cold hypolimnetic water inputs from dams, and extreme weather events can lead to unpredictable temperature fluctuations in natural waters, impacting fish performance and fitness. We hypothesized that fish exposed to such unpredictable fluctuations would exhibit weaker growth and enhanced thermal tolerance compared to predictable conditions. Qingbo (<em>Spinibarbus sinensis</em>) was selected as the experimental subject in this study. The qingbo were divided into a constant temperature group (C, 22 ± 0.5 °C), a predictable temperature fluctuation group (PF, 22 ± 4 °C, first warming, then cooling within a day) and an unpredictable temperature fluctuation group (UF, 22 ± 4 °C, the order of warming or cooling is random). After 40 days of temperature acclimation, the growth, metabolic rate, spontaneous activity, thermal tolerance, plasma cortisol concentration and liver hsp70 level of the fish were measured. Unexpectedly, neither the PF nor the UF group showed decreased growth compared to the C group. This could be attributed to the fact that temperature variation did not lead to a substantial increase in basic energy expenditure. Furthermore, feeding rates increased due to temperature fluctuations, although the difference was not significant. Both the PF and UF groups exhibited increased upper thermal tolerance, but only the UF group exhibited improved lower thermal tolerance and higher liver hsp70 levels compared to the C group. The qingbo that experienced unpredictable temperature fluctuations had the best thermal tolerance among the 3 groups, which might have occurred because they had the highest level of hsp70 expression. This may safeguard fish against the potential lethal consequences of extreme temperatures in the future. These findings suggested that qingbo exhibited excellent adaptability to both predictable and unpredictable temperature fluctuations, which may be associated with frequent temperature fluctuations in its natural habitat.</p></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140855613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-05-03DOI: 10.1016/j.cbpa.2024.111651
Jannik Kuhn , Annika Lindstrom , Helene Volkoff
The pond loach (Misgurnus anguillicaudatus) is an important aquaculture freshwater species, used as an ornamental fish, food source for humans and angling bait. Pond loaches are resistant to fasting and extreme environmental conditions, including temperature and low oxygen levels. Little is known about how these factors affect the feeding physiology and the endocrine regulation of feeding of loaches. In this study, we examined the effects of fasting, as well as increased temperature and decreased oxygen levels on food intake and transcript levels of appetite regulators. Fasted fish had lower blood glucose levels, and lower expression levels of intestine CCK and PYY, and brain CART1, but had higher levels of brain orexin and ghrelin than fed fish. Fish held at 30 °C had higher food intake, glucose levels, and mRNA levels of intestine CCK and PYY, and brain CART2, but lower brain orexin levels than fish at 20 °C. Fish held at low oxygen levels had a lower food intake, higher intestine CCKa and ghrelin, and brain orexin, CART2 and ghrelin mRNA expression levels than fish held at high O2 levels. Our results suggest that fasting and high temperatures increase the expression of orexigenic and anorexigenic factors respectively, whereas the increase in expression of both orexigenic and anorexigenic factors in low O2 environments might not be related to their role in feeding, but possibly to protection from tissue damage. The results of our study might shed new light on how pond loaches are able to cope with extreme environmental conditions such as low food availability, extreme temperatures and hypoxia.
{"title":"Effects of fasting and environmental factors on appetite regulators in pond loach Misgurnus anguillicaudatus","authors":"Jannik Kuhn , Annika Lindstrom , Helene Volkoff","doi":"10.1016/j.cbpa.2024.111651","DOIUrl":"10.1016/j.cbpa.2024.111651","url":null,"abstract":"<div><p>The pond loach (<em>Misgurnus anguillicaudatus</em>) is an important aquaculture freshwater species, used as an ornamental fish, food source for humans and angling bait. Pond loaches are resistant to fasting and extreme environmental conditions, including temperature and low oxygen levels. Little is known about how these factors affect the feeding physiology and the endocrine regulation of feeding of loaches. In this study, we examined the effects of fasting, as well as increased temperature and decreased oxygen levels on food intake and transcript levels of appetite regulators. Fasted fish had lower blood glucose levels, and lower expression levels of intestine CCK and PYY, and brain CART1, but had higher levels of brain orexin and ghrelin than fed fish. Fish held at 30 °C had higher food intake, glucose levels, and mRNA levels of intestine CCK and PYY, and brain CART2, but lower brain orexin levels than fish at 20 °C. Fish held at low oxygen levels had a lower food intake, higher intestine CCKa and ghrelin, and brain orexin, CART2 and ghrelin mRNA expression levels than fish held at high O<sub>2</sub> levels. Our results suggest that fasting and high temperatures increase the expression of orexigenic and anorexigenic factors respectively, whereas the increase in expression of both orexigenic and anorexigenic factors in low O<sub>2</sub> environments might not be related to their role in feeding, but possibly to protection from tissue damage. The results of our study might shed new light on how pond loaches are able to cope with extreme environmental conditions such as low food availability, extreme temperatures and hypoxia.</p></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140860365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-24DOI: 10.1016/j.cbpa.2024.111649
Andrea C. Durant , Andrew Donini
The role of the mosquito excretory organs (Malpighian tubules, MT and hindgut, HG) in ammonia transport as well as expression and function of the Rhesus (Rh protein) ammonia transporters within these organs was examined in Aedes aegypti larvae and adult females. Immunohistological examination revealed that the Rh proteins are co-localized with V-type H+-ATPase (VA) to the apical membranes of MT and HG epithelia of both larvae and adult females. Of the two Rh transporter genes present in A. aegypti, AeRh50–1 and AeRh50–2, we show using quantitative real-time PCR (qPCR) and an RNA in-situ hybridization (ISH) assay that AeRh50–1 is the predominant Rh protein expressed in the excretory organs of larvae and adult females. Further assessment of AeRh50–1 function in larvae and adults using RNAi (i.e. dsRNA-mediated knockdown) revealed significantly decreased [NH4+] (mmol l−1) levels in the secreted fluid of larval MT which does not affect overall NH4+ transport rates, as well as significantly decreased NH4+ flux rates across the HG (haemolymph to lumen) of adult females. We also used RNA sequencing to identify the expression of ion transporters and enzymes within the rectum of larvae, of which limited information currently exists for this important osmoregulatory organ. Of the ammonia transporters in A. aegypti, AeRh50–1 transcript is most abundant in the rectum thus validating our immunohistochemical and RNA ISH findings. In addition to enriched VA transcript (subunits A and d1) in the rectum, we also identified high Na+-K+-ATPase transcript (α subunit) expression which becomes significantly elevated in response to HEA, and we also found enriched carbonic anhydrase 9, inwardly rectifying K+ channel Kir2a, and Na+-coupled cation-chloride (Cl−) co-transporter CCC2 transcripts. Finally, the modulation in excretory organ function and/or Rh protein expression was examined in relation to high ammonia challenge, specifically high environmental ammonia (HEA) rearing of larvae. NH4+ flux measurements using the scanning-ion selective electrode (SIET) technique revealed no significant differences in NH4+ transport across organs comprising the alimentary canal of larvae reared in HEA vs freshwater. Further, significantly increased VA activity, but not NKA, was observed in the MT of HEA-reared larvae. Relatively high Rh protein immunostaining persists within the hindgut epithelium, as well as the ovary, of females at 24–48 h post blood meal corresponding with previously demonstrated peak levels of ammonia formation. These data provide new insight into the role of the excretory organs in ammonia transport physiology and the contribution of Rh proteins in mediating ammonia movement across the epi
{"title":"Ammonia transport in the excretory system of mosquito larvae (Aedes aegypti): Rh protein expression and the transcriptome of the rectum","authors":"Andrea C. Durant , Andrew Donini","doi":"10.1016/j.cbpa.2024.111649","DOIUrl":"https://doi.org/10.1016/j.cbpa.2024.111649","url":null,"abstract":"<div><p>The role of the mosquito excretory organs (Malpighian tubules, MT and hindgut, HG) in ammonia transport as well as expression and function of the Rhesus (Rh protein) ammonia transporters within these organs was examined in <em>Aedes aegypti</em> larvae and adult females. Immunohistological examination revealed that the Rh proteins are co-localized with V-type H<sup>+</sup>-ATPase (VA) to the apical membranes of MT and HG epithelia of both larvae and adult females. Of the two Rh transporter genes present in <em>A. aegypti</em>, <em>AeRh50–1</em> and <em>AeRh50–2</em>, we show using quantitative real-time PCR (qPCR) and an RNA in-situ hybridization (ISH) assay that <em>AeRh50–1</em> is the predominant Rh protein expressed in the excretory organs of larvae and adult females. Further assessment of AeRh50–1 function in larvae and adults using RNAi (i.e. dsRNA-mediated knockdown) revealed significantly decreased [NH<sub>4</sub><sup>+</sup>] (mmol l<sup>−1</sup>) levels in the secreted fluid of larval MT which does not affect overall NH<sub>4</sub><sup>+</sup> transport rates, as well as significantly decreased NH<sub>4</sub><sup>+</sup> flux rates across the HG (haemolymph to lumen) of adult females. We also used RNA sequencing to identify the expression of ion transporters and enzymes within the rectum of larvae, of which limited information currently exists for this important osmoregulatory organ. Of the ammonia transporters in <em>A. aegypti</em>, <em>AeRh50–1</em> transcript is most abundant in the rectum thus validating our immunohistochemical and RNA ISH findings. In addition to enriched VA transcript (subunits A and d1) in the rectum, we also identified high Na<sup>+</sup>-K<sup>+</sup>-ATPase transcript (α subunit) expression which becomes significantly elevated in response to HEA, and we also found enriched carbonic anhydrase 9, inwardly rectifying K<sup>+</sup> channel <em>Kir2a</em>, and Na<sup>+</sup>-coupled cation-chloride (Cl<sup>−</sup>) co-transporter <em>CCC2</em> transcripts. Finally, the modulation in excretory organ function and/or Rh protein expression was examined in relation to high ammonia challenge, specifically high environmental ammonia (HEA) rearing of larvae. NH<sub>4</sub><sup>+</sup> flux measurements using the scanning-ion selective electrode (SIET) technique revealed no significant differences in NH<sub>4</sub><sup>+</sup> transport across organs comprising the alimentary canal of larvae reared in HEA vs freshwater. Further, significantly increased VA activity, but not NKA, was observed in the MT of HEA-reared larvae. Relatively high Rh protein immunostaining persists within the hindgut epithelium, as well as the ovary, of females at 24–48 h post blood meal corresponding with previously demonstrated peak levels of ammonia formation. These data provide new insight into the role of the excretory organs in ammonia transport physiology and the contribution of Rh proteins in mediating ammonia movement across the epi","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2024-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140807151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}