Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology最新文献_第3页

Modulation of mitochondrial dynamics genes and mtDNA during embryonic development and under UVB exposure 在胚胎发育和UVB暴露下线粒体动力学基因和mtDNA的调节。

IF 2.1 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-02-01 DOI: 10.1016/j.cbpa.2024.111790

Thaline de Quadros, Michael Lorenz Jaramillo, Cairé Barreto, Rafael Diego da Rosa, Madson Silveira de Melo , Evelise Maria Nazari

Studies using the embryos of the freshwater prawn Macrobrachium olfersii have reported changes in embryonic cells after exposure to ultraviolet B (UVB) radiation, such as DNA damage and apoptosis activation. Considering the importance of mitochondria in embryonic cells, this study aimed to characterize the aspects of mitochondrial morphofunctionality in M. olfersii embryos and mitochondrial responses to UVB radiation exposure. The coding sequences of genes Tfam, Nrf1, Mfn1, and Drp1 were identified from the transcriptome of M. olfersii embryos. The phylogenetic relationship showed strong amino acid identity and a highly conserved nature of the sequences. Additionally, the number of mitochondrial DNA (mtDNA) copies were higher in the early embryonic days. The results showed that the expression of the analyzed genes was highly regulated during embryonic development, increasing their levels near hatching. Furthermore, when embryos were exposed to UVB radiation, mitochondrial biogenesis was activated, recognized by higher levels of transcripts of genes Tfam and Nrf1, accompanied by mitochondrial fission. Additionally, these mitochondrial events were supported by an increase of mtDNA copies. Our results showed that UVB radiation was able to change the mitochondrial morphofunctionality, and under the current knowledge, certainly compromise embryonic cellular integrity. Additionally, mitochondria is an important cellular target of this radiation and its responses can be used to assess environmental stress caused by UVB radiation in embryos of aquatic species.

利用淡水沼虾（Macrobrachium olfersii）胚胎进行的研究报道了紫外线B （UVB）辐射后胚胎细胞的变化，如DNA损伤和细胞凋亡激活。考虑到线粒体在胚胎细胞中的重要性，本研究旨在表征M. olfersii胚胎线粒体形态功能和线粒体对UVB辐射的反应。从M. olfersii胚胎转录组中鉴定出Tfam、Nrf1、Mfn1和Drp1基因的编码序列。系统发育关系显示出较强的氨基酸同源性和高度保守性。此外，mtDNA拷贝数在胚胎早期较高。结果表明，所分析的基因在胚胎发育过程中表达受到高度调控，在孵化前表达水平增加。此外，当胚胎暴露于UVB辐射时，线粒体生物发生被激活，Tfam和Nrf1基因转录本水平升高，并伴有线粒体裂变。此外，这些线粒体事件得到了mtDNA拷贝增加的支持。我们的研究结果表明，UVB辐射能够改变线粒体的形态功能，并且在目前的知识下，肯定会损害胚胎细胞的完整性。此外，线粒体是该辐射的重要细胞靶点，其响应可用于评估水生物种胚胎中UVB辐射引起的环境应激。

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引用次数: 0

Hypoxia increases intracellular calcium in glutamate-activated horizontal cells of goldfish retina via mitochondrial KATP channels and intracellular stores 缺氧通过线粒体KATP通道和细胞内储存增加了谷氨酸激活的金鱼视网膜水平细胞内钙。

IF 2.1 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-02-01 DOI: 10.1016/j.cbpa.2024.111786

Nicole V. Nagy-Watson , Michael G. Jonz

Central neurons of the common goldfish (Carassius auratus) are exceptional in their capacity to survive Ca²⁺-induced excitotoxicity and cell death during hypoxia. Horizontal cells (HCs) are inhibitory interneurons of the retina that are tonically depolarized by the neurotransmitter, glutamate, yet preserve intracellular Ca²⁺ homeostasis. In HCs isolated from goldfish, and in the absence of glutamatergic input, intracellular Ca²⁺ concentration ([Ca²⁺]_i) is protected from prolonged exposure to hypoxia by mitochondrial ATP-dependent K⁺ (mK_ATP) channel activity. In the present study, we investigated the effects of hypoxia upon [Ca²⁺]_i in isolated HCs during tonic activation by glutamate to better predict the effects of hypoxia in the active retina. Dynamic changes in [Ca²⁺]_i were measured using the ratiometric Ca²⁺ indicator, Fura-2. Application of 100 μM glutamate during hypoxia (P_O2 = 25 mmHg) produced a 1.3-fold greater rise in [Ca²⁺]_i compared to the same glutamate stimulus during normoxia. The hypoxia-dependent increase in [Ca²⁺]_i was abolished by application of 5-hydroxydecanoic acid, which renders mK_ATP channels inactive. Extracellular Ca²⁺ did not contribute to the elevated [Ca²⁺]_i observed during hypoxia, as the effect persisted in Ca²⁺-free solution and during application of verapamil, an L-type Ca²⁺ channel blocker. By contrast, inhibition of the mitochondrial Ca²⁺ uniporter or ryanodine receptors (with ruthenium red or ryanodine, respectively) abolished the hypoxia-dependent rise in [Ca²⁺]_i. This study reports an mK_ATP-dependent rise in [Ca²⁺]_i during hypoxia in HCs activated by glutamate, and suggests roles for the mitochondria and intracellular Ca²⁺ stores in regulating this mechanism.

普通金鱼（Carassius auratus）的中枢神经元在缺氧期间存活Ca2+诱导的兴奋性毒性和细胞死亡的能力异常。水平细胞（HCs）是视网膜的抑制性中间神经元，被神经递质谷氨酸强直地去极化，但保持细胞内Ca2+稳态。在从金鱼中分离的hc中，在没有谷氨酸能输入的情况下，细胞内Ca2+浓度（[Ca2+]i）通过线粒体atp依赖性K+ (mKATP)通道活性免受长时间暴露于缺氧的影响。在本研究中，我们研究了在谷氨酸强张性激活过程中缺氧对离体hc [Ca2+]i的影响，以更好地预测缺氧对活性视网膜的影响。使用比例Ca2+指示剂Fura-2测量[Ca2+]i的动态变化。在低氧条件下（PO2 = 25 mmHg）应用100 μM谷氨酸产生的[Ca2+]i比正常缺氧条件下相同的谷氨酸刺激高1.3倍。缺氧依赖性的[Ca2+]i的增加被5-羟基癸酸的应用所消除，这使得mKATP通道失活。在缺氧期间观察到的细胞外Ca2+并没有导致[Ca2+]升高，因为在无Ca2+溶液和使用维拉帕米（一种l型Ca2+通道阻滞剂）期间，这种作用持续存在。相比之下，抑制线粒体Ca2+单转运体或ryanodine受体（分别使用钌红或ryanodine）可以消除缺氧依赖性的[Ca2+]i升高。本研究报道了谷氨酸激活的hc缺氧时mkatp依赖性的[Ca2+]i升高，并提示线粒体和细胞内Ca2+储存在调节这一机制中的作用。

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引用次数: 0

HSP70 is upregulated after heat but not freezing stress in the freeze-tolerant cricket Gryllus veletis 抗冻蟋蟀热应激后HSP70表达上调，而冰冻应激后不上调。

IF 2.1 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-02-01 DOI: 10.1016/j.cbpa.2024.111791

Victoria E. Adams, Maranda L. van Oirschot, Jantina Toxopeus

Heat shock proteins (HSPs) are well known to prevent and repair protein damage caused by various abiotic stressors, but their role in low temperature and freezing stress is not well-characterized in insects compared to other thermal challenges such as heat stress. Ice formation in and around cells is hypothesized to cause protein damage, yet many species of insects can survive freezing, suggesting HSPs may be an important mechanism in freeze tolerance. Here, we studied HSP70 in a freeze-tolerant cricket Gryllus veletis to better understand the role of HSPs in this phenomenon. We measured expression of one heat-inducible HSP70 isoform at the mRNA level (using RT-qPCR), as well as the relative abundance of total HSP70 protein (using semi-quantitative Western blotting), in five tissues from crickets exposed to a survivable heat treatment (2 h at 40 °C), a 6-week fall-like acclimation that induces freeze tolerance, and a survivable freezing treatment (1.5 h at −8 °C). While HSP70 expression was upregulated by heat at the mRNA or protein level in all tissues studied (fat body, Malphigian tubules, midgut, femur muscle, nervous system ganglia), no tissue exhibited HSP70 upregulation within 2–24 h following a survivable freezing stress. During fall-like acclimation to mild low temperatures, we only saw moderate upregulation of HSP70 at the protein level in muscle, and at the RNA level in fat body and nervous tissue. Although HSP70 is important for responding to a wide range of stressors, our work suggests that this chaperone may be less critical in the preparation for, and response to, moderate freezing stress.

众所周知，热休克蛋白（HSPs）可以预防和修复由各种非生物应激源引起的蛋白质损伤，但与热应激等其他热挑战相比，它们在低温和冷冻应激中的作用在昆虫中尚未得到很好的表征。据推测，细胞内部和周围的冰形成会导致蛋白质损伤，但许多昆虫物种可以在冷冻中存活，这表明热休克蛋白可能是耐寒性的重要机制。在这里，我们研究了耐冻蟋蟀Gryllus veletis中的HSP70，以更好地了解HSPs在这一现象中的作用。我们测量了一种热诱导型HSP70亚型在mRNA水平上的表达（使用RT-qPCR），以及总HSP70蛋白的相对丰度（使用半定量Western blotting），这些组织来自暴露于可存活的热处理（2 h, 40 °C）， 6周的诱导抗冻的下降样驯化，以及可存活的冷冻处理（1.5 h, -8 °C）的蟋蟀。在所有研究组织（脂肪体、马氏小管、中肠、股骨肌、神经系统神经节）中，高温在mRNA或蛋白水平上上调了HSP70的表达，但在存活的冷冻应激后2-24 h内，没有组织表现出HSP70的上调。在轻度低温的类秋季驯化过程中，我们只观察到肌肉蛋白水平、脂肪体和神经组织RNA水平的HSP70适度上调。尽管HSP70对于应对多种应激源很重要，但我们的研究表明，这种伴侣蛋白在准备和应对中度冰冻应激时可能不那么重要。

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引用次数: 0

Kinetic comparisons of jaw opening, jaw closing and locomotor muscles 下颌张开、下颌闭合和运动肌肉的动力学比较。

IF 2.1 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-02-01 DOI: 10.1016/j.cbpa.2024.111782

Clinton J. Moran , Shannon P. Gerry

Understanding contraction dynamics of skeletal muscle is critically important to appreciate performance capabilities of skeletal structures, especially for structures responsible for feeding and/or locomotion. Furthermore, it is important to understand how temperature can impact contraction dynamics in vertebrates that are regularly exposed to fluctuations in temperature. We aimed to address differences between jaw opening (sternhyoideus), jaw closing (adductor mandibulae) and locomotor (abductor superficialis) muscle contraction dynamics in a labrid fish. Additionally, we aimed to understand how temperature changes impact contraction kinetics in these muscles. To address these aims we collected cunner (Tautogolabrus adspersus) from Long Island Sound and removed their primary locomotor and jaw opening/closing muscles. Following dissection, the muscles were placed on a muscle ergometer that controlled length, stimulus duration and stimulation intensity. Muscles were exposed to 7, 15 and 22 °C for all experiments. We found that the swimming muscle was slower to contract and relax than both feeding muscles. Swimming muscle produced more power than feeding muscles when tested at 8 Hz and 15 °C. Jaw closing muscle produced more force than the other two muscle types when tested at22 °C. Despite these differences, muscle contraction kinetics were remarkably similar across the three muscle types and temperatures. To our knowledge this is the first study to measure in vitro contraction dynamics of fish jaw opening and closing muscle. This advances the understanding of the physiological capabilities of these muscles. Additionally, differences in contraction dynamics can further our understanding of the physiological limits temperature impart on whole muscle contraction.

了解骨骼肌的收缩动力学对于了解骨骼结构的性能极其重要，尤其是负责进食和/或运动的结构。此外，了解温度如何影响经常暴露于温度波动的脊椎动物的收缩动力学也非常重要。我们的目的是研究唇鱼的下颌张开肌（胸下肌）、下颌闭合肌（下颌内收肌）和运动肌（外展浅肌）收缩动力学之间的差异。此外，我们还希望了解温度变化如何影响这些肌肉的收缩动力学。为了实现这些目标，我们从长岛湾收集了鲯鳅（Tautogolabrus adspersus），并取出了它们的主要运动肌和下颌张开/闭合肌。解剖后，肌肉被放置在一个可控制长度、刺激持续时间和刺激强度的肌肉测力计上。在所有实验中，肌肉分别暴露在 7、15 和 22 °C 的环境中。我们发现，游泳肌的收缩和放松速度均慢于两种进食肌。在 8 赫兹和 15 °C的条件下，游泳肌比进食肌产生更大的力量。在22 °C条件下测试时，下颌闭合肌比其他两种肌肉产生的力量更大。尽管存在这些差异，但三种肌肉类型和温度下的肌肉收缩动力学非常相似。据我们所知，这是首次测量鱼类下颌开合肌体外收缩动力学的研究。这有助于了解这些肌肉的生理机能。此外，收缩动力学的差异还能让我们进一步了解温度对整个肌肉收缩的生理限制。

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引用次数: 0

Prolactin locally mediates follicular atresia in hyperprolactinemic vizcachas (Rodentia, Chinchillidae) 催乳素局部介导高催乳素血症兔的卵泡闭锁（啮齿目，金鸡科）。

IF 2.1 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-02-01 DOI: 10.1016/j.cbpa.2024.111787

Santiago A. Cortasa , Luisa A. Quiroga-Baeza , Alejandro R. Schmidt , Sofía Proietto , Maria C. Corso , Alfredo D. Vitullo , Verónica B. Dorfman , Julia Halperin

Infertility in hyperprolactinemic females is attributed to the dysregulation of GnRH release, subsequently affecting gonadotropin levels, and ultimately leading to anovulation. However, in addition to the hypothalamus, prolactin receptor (PRLR) is expressed in ovaries as well, suggesting potential local effects of PRL in cases of hyperprolactinemia. We have developed an experimental model of sulpiride (SPD)-induced hyperprolactinemia using a wild rodent, the plains vizcacha, and studied the implications of pharmacological PRL levels on folliculogenesis and steroid production. Ovaries of SPD females showed a striking number of atretic follicles along with a reduction in the collective number of viable follicles leading to a higher atretic/viable follicle ratio compared to that of control females (CTL) (P < 0.05). In terms of sensitivity to the hormonal environment, SPD ovaries substantially changed their potential responsiveness to pituitary PRL, as evidenced by the three-fold increase in PRLR expression alongside heightened expression of both gonadotropic receptors in comparison to CTL ovaries (P < 0.05). Circulating estradiol (E2) values doubled post-treatment in the SPD females, which also showed higher expressions of aromatase and 17β-hydroxysteroid dehydrogenase, along with both E2 receptors, ERα and ERβ than the CTL group (P < 0.05). Our findings strongly suggest that hyperprolactinemia-dependent dysregulation of ovarian function can be explained at least partially, by PRL direct actions facilitated by the heightened expression of PRLR in follicles and corpora lutea. Possibly these PRL actions synergize with those triggered by gonadotropic hormones ultimately leading to alteration of the steroidogenic pathway, folliculogenesis disruption and increased atresia.

高泌乳素血症女性的不孕是由于GnRH释放失调，随后影响促性腺激素水平，最终导致无排卵。然而，除了下丘脑，催乳素受体（PRLR）也在卵巢中表达，这表明PRL在高催乳素血症病例中可能具有局部作用。我们利用野生啮齿动物平原维扎卡建立了沙匹利（SPD）诱导的高催乳素血症的实验模型，并研究了PRL药理学水平对卵泡发生和类固醇产生的影响。SPD雌性卵巢出现显著的闭锁卵泡数量，同时活卵泡总数减少，导致闭锁/活卵泡比高于对照组（CTL）（P < 0.05）。在对激素环境的敏感性方面，SPD卵巢对垂体PRL的潜在反应性显著改变，与CTL卵巢相比，PRLR的表达增加了3倍，两种促性腺激素受体的表达均增加（P < 0.05）。SPD雌性小鼠循环雌二醇（E2）值增加一倍，芳香化酶、17β-羟基类固醇脱氢酶以及E2受体、ERα和ERβ的表达均高于CTL组（P < 0.05）。我们的研究结果强烈表明，高催乳素血症依赖性卵巢功能失调至少可以部分解释为PRL的直接作用，而PRLR在卵泡和黄体中的表达升高促进了PRL的直接作用。可能这些PRL作用与促性腺激素触发的作用协同作用，最终导致类固醇生成途径的改变，卵泡发生中断和闭锁增加。

{"title":"Prolactin locally mediates follicular atresia in hyperprolactinemic vizcachas (Rodentia, Chinchillidae)","authors":"Santiago A. Cortasa , Luisa A. Quiroga-Baeza , Alejandro R. Schmidt , Sofía Proietto , Maria C. Corso , Alfredo D. Vitullo , Verónica B. Dorfman , Julia Halperin","doi":"10.1016/j.cbpa.2024.111787","DOIUrl":"10.1016/j.cbpa.2024.111787","url":null,"abstract":"<div><div>Infertility in hyperprolactinemic females is attributed to the dysregulation of GnRH release, subsequently affecting gonadotropin levels, and ultimately leading to anovulation. However, in addition to the hypothalamus, prolactin receptor (PRLR) is expressed in ovaries as well, suggesting potential local effects of PRL in cases of hyperprolactinemia. We have developed an experimental model of sulpiride (SPD)-induced hyperprolactinemia using a wild rodent, the plains vizcacha, and studied the implications of pharmacological PRL levels on folliculogenesis and steroid production. Ovaries of SPD females showed a striking number of atretic follicles along with a reduction in the collective number of viable follicles leading to a higher atretic/viable follicle ratio compared to that of control females (CTL) (<em>P</em> < 0.05). In terms of sensitivity to the hormonal environment, SPD ovaries substantially changed their potential responsiveness to pituitary PRL, as evidenced by the three-fold increase in PRLR expression alongside heightened expression of both gonadotropic receptors in comparison to CTL ovaries (<em>P</em> < 0.05). Circulating estradiol (E2) values doubled post-treatment in the SPD females, which also showed higher expressions of aromatase and 17β-hydroxysteroid dehydrogenase, along with both E2 receptors, ERα and ERβ than the CTL group (<em>P</em> < 0.05). Our findings strongly suggest that hyperprolactinemia-dependent dysregulation of ovarian function can be explained at least partially, by PRL direct actions facilitated by the heightened expression of PRLR in follicles and corpora lutea. Possibly these PRL actions synergize with those triggered by gonadotropic hormones ultimately leading to alteration of the steroidogenic pathway, folliculogenesis disruption and increased atresia.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"300 ","pages":"Article 111787"},"PeriodicalIF":2.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142792933","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}

引用次数: 0

Developing under artificial light is not so bright: Oxidative stress as a physiological response to light pollution across amphibian life stages

IF 2.1 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-01-31 DOI: 10.1016/j.cbpa.2025.111819

Tamara G. Petrović , Jelena P. Gavrić-Čampar , Pablo Burraco , Branka R. Gavrilović , Svetlana G. Despotović , Tijana B. Radovanović , Ana Radmilović , Marko Mirč , Nataša Tomašević Kolarov , Marko D. Prokić

Light pollution has emerged as a new environmental challenge. Natural light has long been a selecting force in shaping physiological, morphological and behavioral traits across species. The introduction of artificial light at night (ALAN) disrupts the natural light-dark cycle, affecting a broad range of biological processes. In amphibians, ALAN has been suggested as a potential driver behind demographic declines in recent years. In this study, we investigated how exposure to cold LED light affects the development, body length, and oxidative status of the European tree frog (Hyla arborea). Individuals were exposed to ALAN from egg hatching (GS25) to two developmental endpoints: the larvae (GS38) and the juveniles. The experiment included three night-time light conditions: a natural dark control (<0.3 lx), LED light intensity at 20 lx, and LED light intensity at 90 lx. Larvae reared under artificial light reached metamorphosis in a shorter period and exhibited larger body sizes. Nocturnal light also induced changes in oxidative status across life stages. Tadpoles under both 20 lx and 90 lx levels experienced greater oxidative damage of lipids. Likewise, juveniles had higher oxidative damage of proteins and elevated activities of the first-line antioxidant defense enzymes (SOD, CAT and GSH-Px) in response to both light intensities. Our results show that exposure to ALAN shapes development and body size of amphibians, which appears to be accompanied by disturbances in redox balance. Overall, we highlight that ALAN can be a factor affecting amphibian populations, and thus it should be taken into consideration in future conservation strategies.

{"title":"Developing under artificial light is not so bright: Oxidative stress as a physiological response to light pollution across amphibian life stages","authors":"Tamara G. Petrović , Jelena P. Gavrić-Čampar , Pablo Burraco , Branka R. Gavrilović , Svetlana G. Despotović , Tijana B. Radovanović , Ana Radmilović , Marko Mirč , Nataša Tomašević Kolarov , Marko D. Prokić","doi":"10.1016/j.cbpa.2025.111819","DOIUrl":"10.1016/j.cbpa.2025.111819","url":null,"abstract":"<div><div>Light pollution has emerged as a new environmental challenge. Natural light has long been a selecting force in shaping physiological, morphological and behavioral traits across species. The introduction of artificial light at night (ALAN) disrupts the natural light-dark cycle, affecting a broad range of biological processes. In amphibians, ALAN has been suggested as a potential driver behind demographic declines in recent years. In this study, we investigated how exposure to cold LED light affects the development, body length, and oxidative status of the European tree frog (<em>Hyla arborea</em>). Individuals were exposed to ALAN from egg hatching (GS25) to two developmental endpoints: the larvae (GS38) and the juveniles. The experiment included three night-time light conditions: a natural dark control (<0.3 lx), LED light intensity at 20 lx, and LED light intensity at 90 lx. Larvae reared under artificial light reached metamorphosis in a shorter period and exhibited larger body sizes. Nocturnal light also induced changes in oxidative status across life stages. Tadpoles under both 20 lx and 90 lx levels experienced greater oxidative damage of lipids. Likewise, juveniles had higher oxidative damage of proteins and elevated activities of the first-line antioxidant defense enzymes (SOD, CAT and GSH-Px) in response to both light intensities. Our results show that exposure to ALAN shapes development and body size of amphibians, which appears to be accompanied by disturbances in redox balance. Overall, we highlight that ALAN can be a factor affecting amphibian populations, and thus it should be taken into consideration in future conservation strategies.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"302 ","pages":"Article 111819"},"PeriodicalIF":2.1,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143080836","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}

引用次数: 0

Sibling similarity in telomere length in Adélie penguin chicks 阿德利企鹅雏鸟端粒长度的同胞相似性。

IF 2.1 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-01-28 DOI: 10.1016/j.cbpa.2025.111818

Coline Marciau , Sophie Bestley , David Costantini , Olivia Hicks , Mark Hindell , Akiko Kato , Thierry Raclot , Cécile Ribout , Yan Ropert-Coudert , Frederic Angelier

Early life telomere length is thought to influence and predict an individual's fitness. It has been shown to vary significantly in early life compared to adulthood. Investigating the factors influencing telomere length in young individuals is therefore of particular interest, especially as the relative importance of heredity compared to post-natal conditions remains largely uncertain. Adélie penguins are eco-indicators of the Antarctic ecosystem and their population are currently undergoing variable trajectories due to climate change. Here, we conducted a correlative study to investigate how telomere length was influenced by external and internal factors in Adélie penguin chicks. We found that most of the parameters we tested, including sex, body mass, brood size and hatching order as well as parental foraging trip duration, did not significantly influence chick telomere length at 32 days. However, siblings had similar telomere length, suggesting that hereditary factors play a stronger role in determining telomere length at this stage compared to the post-natal environment. In addition, telomere length and oxidative damage did not directly correlate but did interact in a complex way mediated by chick mass. High levels of oxidative damage were associated with longer telomeres in heavy chicks, whereas they were associated with shorter telomeres in light chicks. Although this mass-dependent relationship between telomere length and oxidative damage needs to be confirmed in future studies, it could reflect two different scenarios: (1) short telomeres may mimic the cost of poor nutritional conditions and oxidative damage in light chicks; (2) long telomeres may be maintained despite high oxidative damage in heavy chicks thanks to optimal nutritional conditions.

{"title":"Sibling similarity in telomere length in Adélie penguin chicks","authors":"Coline Marciau , Sophie Bestley , David Costantini , Olivia Hicks , Mark Hindell , Akiko Kato , Thierry Raclot , Cécile Ribout , Yan Ropert-Coudert , Frederic Angelier","doi":"10.1016/j.cbpa.2025.111818","DOIUrl":"10.1016/j.cbpa.2025.111818","url":null,"abstract":"<div><div>Early life telomere length is thought to influence and predict an individual's fitness. It has been shown to vary significantly in early life compared to adulthood. Investigating the factors influencing telomere length in young individuals is therefore of particular interest, especially as the relative importance of heredity compared to post-natal conditions remains largely uncertain. Adélie penguins are eco-indicators of the Antarctic ecosystem and their population are currently undergoing variable trajectories due to climate change. Here, we conducted a correlative study to investigate how telomere length was influenced by external and internal factors in Adélie penguin chicks. We found that most of the parameters we tested, including sex, body mass, brood size and hatching order as well as parental foraging trip duration, did not significantly influence chick telomere length at 32 days. However, siblings had similar telomere length, suggesting that hereditary factors play a stronger role in determining telomere length at this stage compared to the post-natal environment. In addition, telomere length and oxidative damage did not directly correlate but did interact in a complex way mediated by chick mass. High levels of oxidative damage were associated with longer telomeres in heavy chicks, whereas they were associated with shorter telomeres in light chicks. Although this mass-dependent relationship between telomere length and oxidative damage needs to be confirmed in future studies, it could reflect two different scenarios: (1) short telomeres may mimic the cost of poor nutritional conditions and oxidative damage in light chicks; (2) long telomeres may be maintained despite high oxidative damage in heavy chicks thanks to optimal nutritional conditions.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"302 ","pages":"Article 111818"},"PeriodicalIF":2.1,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143068755","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}

引用次数: 0

The potential for heat shock exposure during early development to alter the molecular responses to subsequent exposure to heat stress in the rainbow trout

IF 2.1 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-01-23 DOI: 10.1016/j.cbpa.2025.111817

Rob J. McFarling , Mickael Teixeira Alves , Anke Lange , Millie Clark , Harry J. Woodrow , Ioanna Katsiadaki , Ronny van Aerle , Eduarda M. Santos

Fish are ectothermic animals with temperature playing a key role in their health, growth and survival. Greater occurrence of heat waves and temperature extremes, as a result of global climate change, has the potential to impact both wild and farmed populations. Within aquaculture, production is threatened by a multitude of stressors, including adverse temperatures. The propensity for environmental temperature during early embryo development to influence later life transcriptomic responses has been observed in numerous animal species, and, if harnessed, could provide a method for inducing phenotypic changes in adult aquaculture species. We hypothesise that exposure of rainbow trout embryos to temperature stress results in alterations to transcriptional responsiveness upon re-exposure later in life. To test this hypothesis, we exposed embryos to a range of different heat shock treatments during early development and then analysed their response to thermal stress at five days post hatch (dph), in comparison to naïve fish that experienced no early development heat shock. Hsp70a and hsp70b transcription was measured (using RT-QPCR) as a biomarker for thermal stress response. Significantly greater transcriptional induction of hsp70a in response to post-hatch thermal stress was found in heat shocked larvae compared to naïve larvae (p = 0.0085). The timing, intensity and duration of the initial heat shock was not found to statistically influence the alteration of hsp induction when compared to that of naïve larvae. Together, these results support our hypothesis that heat shock during early development has the potential to affect responsiveness to the same stressor later in life. Future studies should focus on understanding whether this could be utilised to increase robustness of fish in aquaculture.

鱼类是外温动物，温度对其健康、生长和生存起着关键作用。全球气候变化导致热浪和极端温度的增加，有可能对野生鱼类和养殖鱼类造成影响。在水产养殖业中，生产受到包括不利温度在内的多种压力因素的威胁。在许多动物物种中观察到，早期胚胎发育过程中的环境温度会影响后期的转录组反应，如果加以利用，可以为诱导成年水产养殖物种的表型变化提供一种方法。我们的假设是，虹鳟胚胎暴露于温度胁迫会导致后期再次暴露时转录反应的改变。为了验证这一假设，我们在胚胎早期发育期间将其暴露于一系列不同的热休克处理中，然后在孵化后五天（dph）分析其对热应力的反应，并与没有经历早期发育热休克的天真鱼进行比较。采用 RT-QPCR 测量 Hsp70a 和 hsp70b 的转录，作为热应激反应的生物标记。与未受热休克的幼鱼相比，受热休克的幼鱼对孵化后热应激反应的 hsp70a 转录诱导明显增加（p = 0.0085）。与天真幼虫相比，初始热休克的时间、强度和持续时间并未对 hsp 诱导的变化产生统计学影响。总之，这些结果支持了我们的假设，即早期发育过程中的热休克有可能影响日后对相同应激源的反应。未来的研究应侧重于了解是否可以利用这一点来提高水产养殖中鱼类的健壮性。

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引用次数: 0

Gut microbiomes are largely unchanged when exposed to their amphibian host's latitudinally variable upper thermal limit

IF 2.1 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-01-22 DOI: 10.1016/j.cbpa.2025.111816

Grace J. Vaziri , Bryanna Caicedo , Nicole Dahrouge , William G. Ryerson , Jon M. Davenport , Maria Stager , Korin R. Jones , Carlin Frost , Chad L. Seewagen , Tracy A.G. Rittenhouse , Daniel I. Bolnick

Climate change will increase the frequency and severity of temperature extremes. Links between host thermal physiology and their gut microbiota suggest that organisms' responses to future climates may be mediated by their microbiomes, raising the question of how the thermal environment influences the microbiome itself. Vertebrate gut microbiomes influence the physiological plasticity of their hosts via effects on immunity, metabolism, and nutrient uptake. The gut microbiota of ectothermic vertebrates in particular are responsive to long-term, sub-lethal gradual increases in environmental temperature. Whether and how the gut microbiota respond to brief exposure to temperatures at the upper limit of host physiological tolerance (CT_max) is poorly understood but could have downstream effects on host fitness. We assayed the CT_max of wood frogs (Lithobates sylvaticus) from 15 populations across a 10° latitudinal gradient. We then characterized the gut microbiota of juveniles at two time points following exposure to CT_max. Frogs from higher latitudes had lower thermal tolerance (lower CT_max) than those from lower latitudes. Unexpectedly, exposure to upper survivable temperature had little to no detectable effect on the frogs' microbiota richness, stability, or composition. Instead, we found a strong effect of time in which frogs kept in recovery conditions for four days had less diverse, but more stable gut microbiota than those that had recovered for only one day, regardless of CT_max exposure. We conclude that while wood frogs from higher latitudes have reduced thermal tolerances than those from lower latitudes, their microbial communities are largely unaffected by brief exposure to high temperatures at the edge of their physiological limits.

气候变化将增加极端温度出现的频率和严重程度。宿主热生理学与其肠道微生物群之间的联系表明，生物对未来气候的反应可能是由其微生物群介导的，这就提出了热环境如何影响微生物群本身的问题。脊椎动物肠道微生物群通过对免疫、新陈代谢和营养吸收的影响来影响宿主的生理可塑性。尤其是外温脊椎动物的肠道微生物群对环境温度长期、亚致死性的逐渐升高有反应。对于肠道微生物群是否以及如何对短暂暴露于宿主生理耐受上限（CTmax）的温度做出反应，目前还知之甚少，但这可能会对宿主的健康状况产生下游影响。我们测定了林蛙（Lithobates sylvaticus）在 10° 纬度梯度上 15 个种群的 CTmax。然后，我们对暴露于CTmax后两个时间点的幼蛙肠道微生物群进行了表征。纬度较高的蛙类比纬度较低的蛙类具有更低的热耐受性（更低的CTmax）。出乎意料的是，暴露于较高的可存活温度对蛙类微生物群的丰富度、稳定性或组成几乎没有影响。相反，我们发现了时间的强烈影响，在恢复条件下饲养四天的蛙类与只恢复了一天的蛙类相比，肠道微生物群的多样性较低，但稳定性较高，与暴露于 CTmax 的情况无关。我们的结论是，虽然高纬度地区的林蛙比低纬度地区的林蛙耐热性更差，但它们的微生物群落基本上不受短暂暴露于其生理极限边缘高温的影响。

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引用次数: 0

Impacts of severity and region of gill tissue resection on regeneration in Atlantic salmon (Salmo salar) 鳃组织切除的严重程度和区域对大西洋鲑鱼再生的影响。

IF 2.1 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-01-19 DOI: 10.1016/j.cbpa.2025.111815

Ensiyeh Ghanizadeh-Kazerouni , Dean J. Yoo , Simon R.M. Jones , Colin J. Brauner

In a previous study, we demonstrated successful regeneration of Atlantic salmon gill tissue following up to 50 % filament resection. The present study explored 1) the capacity of gill tissue to regenerate following more severe trauma, 2) if regeneration potential varies across regions of the arch, and 3) how tissue loss impacts the physiology of neighboring unresected filaments. Fish were divided between two resected groups and a control non-resected one. In resection group-1, fish underwent 50 % and 75 % resection in the ventral and medial-dorsal regions of the first arch, while in resection group-2, the location of resection levels was reversed. The degree of filament regeneration and physiology of unresected filaments were measured at 4, 12 and 20 weeks-post-resection (WPR). Overall, the degree of regeneration was significantly higher in 50 % resected filaments relative to 75 % resected filaments. The degree of regeneration did not differ significantly between the resected groups for either of resection levels, suggesting negligible impact of filament location on arch on regeneration. The concentration of oxidized glutathione (GSSG), total glutathione (GSH), and citrate synthase activity (CSA) in intact filaments were comparable between resected and control fish at both 4 and 20 WPR. However, GSH concentration varied among resected fish with those exhibited higher GSH in intact filaments showed lower regeneration of 50 % resected filaments at 20 WPR. Our results indicate that gill tissue loss exceeding 50 % may significantly impair regeneration and that this level of tissue loss is not associated with a compensatory response (e.g. GSSG, GSH, CSA) of neighboring gill tissue.

在之前的研究中，我们成功地证明了大西洋鲑鱼鳃组织再生后高达50% %的纤维切除。本研究探讨了1)严重创伤后鳃组织的再生能力，2)不同弓区的再生潜力是否不同，以及3)组织损失如何影响邻近未切除细丝的生理。鱼被分为两个切除组和一个未切除的对照组。在切除组1中，鱼在第一弓的腹侧和中背区进行了50% %和75% %的切除，而在切除组2中，切除水平的位置相反。在术后4、12和20 周（WPR）测量未切除细丝的再生程度和生理状况。总的来说，50% %的断丝的再生程度明显高于75% %的断丝。两组间的再生程度无显著差异，表明纤维位置对弓的影响可以忽略不计。在4 WPR和20 WPR时，完整纤维中氧化谷胱甘肽（GSSG）、总谷胱甘肽（GSH）浓度和柠檬酸合成酶活性（CSA）在切除鱼和对照鱼之间相当。然而，GSH浓度在被切除的鱼中有所不同，在完整的细丝中表现出较高的GSH的鱼在20 WPR时，被切除的细丝的再生率低于50% %。我们的研究结果表明，鳃组织损失超过50% %可能会严重损害再生，并且这种水平的组织损失与邻近鳃组织的代偿反应（例如GSSG， GSH， CSA）无关。

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