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

Analysis of the transcriptional mechanisms of yellowfin tuna (Thunnus albacares) juveniles in response to acute cold stress in brain and muscle tissues 黄鳍金枪鱼幼鱼脑和肌肉组织响应急性冷应激的转录机制分析。

IF 2.2 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-12-16 DOI: 10.1016/j.cbpa.2025.111962

Junhua Huang , Zhengyi Fu , Zhenhua Ma

La Nina events caused by global climate change have amplified ocean temperature fluctuations, challenging aquaculture operations for species such as yellowfin tuna (Thunnus albacares), particularly under winter cooling conditions. To investigate the physiological responses of juvenile tuna, two experimental treatments low-temperature group (LT, 24 °C) and ultra-low-temperature group (ULT, 18 °C) were established and sampled at 0, 12, 24, and 36 h, alongside a 30 °C control group (CG). Transcriptomic analysis of the brain, red muscle, and white muscle revealed that, upon sensing low temperatures, the brain activated multiple immune, stress, and endocrine pathways, including TNF and Toll-like receptor signaling. In response to this activation, genes such as hspa5, hsp90aa1.2, STAT1, and CXCR2 showed altered expression, indicating their involvement in downstream stress and immune regulatory processes. Cold-stress signals were then transmitted to the muscles, which adapted via key genes linked to energy metabolism (glycolysis, gluconeogenesis, fatty acid oxidation), protein folding (HSPA1s), and myofiber remodeling (col6a2, PXN). Notably, responses were more pronounced at 18 °C. Muscle contraction-related genes (myl2b, myl13) collaborated with signaling molecules (SRC, PIK3CA_B_D) to form a stress-response network ensuring efficient energy supply, fiber stability, and contractile function. Furthermore, muscle-derived metabolites and stress proteins are fed back to the brain, establishing a cross-tissue, bidirectional regulatory loop that preserves energy provision, immune defense, and muscle integrity under cold stress. These findings advance our understanding of the molecular responses in yellowfin tuna to low-temperature conditions, offering valuable guidance for improving cold tolerance and optimizing aquaculture and ecological adaptation strategies.

全球气候变化引起的拉尼娜现象加剧了海洋温度波动，对黄鳍金枪鱼等物种的水产养殖作业构成挑战，特别是在冬季降温条件下。为了研究金枪鱼幼鱼的生理反应，我们建立了低温组（LT, 24 °C）和超低温组（ULT, 18 °C）两个实验处理，分别在0、12、24和36 h取样，并在30 °C的对照组（CG）中取样。脑、红肌和白肌的转录组学分析显示，在感知低温时，大脑激活了多种免疫、应激和内分泌途径，包括TNF和toll样受体信号。在这种激活的反应中，hspa5、hsp90aa1.2、STAT1和CXCR2等基因表达改变，表明它们参与下游应激和免疫调节过程。然后，冷应激信号被传递到肌肉，肌肉通过与能量代谢（糖酵解、糖异生、脂肪酸氧化）、蛋白质折叠（hspa1）和肌纤维重塑（col6a2、PXN）相关的关键基因进行适应。值得注意的是，反应在18 °C时更为明显。肌肉收缩相关基因（myl2b、myl13）与信号分子（SRC、PIK3CA_B_D）协同形成应激反应网络，确保有效的能量供应、纤维稳定性和收缩功能。此外，肌肉衍生的代谢物和应激蛋白被反馈到大脑，建立一个跨组织的双向调节回路，在冷应激下保持能量供应、免疫防御和肌肉完整性。这些发现有助于我们进一步了解黄鳍金枪鱼对低温条件的分子反应，为提高黄鳍金枪鱼的耐寒性、优化养殖和生态适应策略提供有价值的指导。

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引用次数: 0

Offspring innate immunity varies with parental age in a long-lived seabird 在长寿的海鸟中，后代的先天免疫随父母年龄的变化而变化。

IF 2.2 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-12-16 DOI: 10.1016/j.cbpa.2025.111963

Beatrice Berardi , Gianluca Damiani , Gábor Á. Czirják , Silvia Filippi , Giacomo Dell'Omo , David Costantini

Parental age at reproduction is increasingly recognized as a factor influencing offspring lifespan and other fitness-related traits, yet the underlying proximate physiological mechanisms remain poorly understood. Immune function and oxidative status are two potential mediators of age-related parental effects, as both are key hallmarks of ageing. However, very few studies have examined the relationship between parental age and offspring physiological condition in wild populations. We examined immunological and cellular mechanisms potentially responsible for parental age effects in the long-lived seabird Scopoli's shearwater (Calonectris diomedea). We measured 10 markers of immune function and oxidative status in 35 chicks from either younger or older parents at two different developmental phases: one month of age and at fledging. Chicks of younger parents exhibited higher haptoglobin levels at fledging compared to chicks of older parents. No effects of parental age were found on leukocyte profiles, humoral components of acquired immunity, antioxidant enzyme activity, or DNA damage in the offspring. Our results suggest, whilst chicks of younger parents might experience more stressful conditions, overall mechanisms supporting somatic maintenance might shield offsprings from the transgenerational transfer of molecular damage that parents accumulate with age. Our findings provide novel insights into the physiological bases of parental age effects in a long-lived species.

父母的生育年龄越来越被认为是影响后代寿命和其他健康相关特征的一个因素，但潜在的近似生理机制仍然知之甚少。免疫功能和氧化状态是与年龄相关的亲代效应的两个潜在介质，因为它们都是衰老的关键标志。然而，很少有研究调查了野生种群中亲代年龄与后代生理状况之间的关系。我们研究了长寿海鸟Scopoli's shearwater （Calonectris diomedea）中可能负责父母年龄效应的免疫和细胞机制。我们测量了35只雏鸡的10种免疫功能和氧化状态标记物，这些雏鸡来自年龄较小或较大的父母，分别处于两个不同的发育阶段：一个月龄和羽翼期。年轻父母的雏鸡在羽化时表现出较高的触珠蛋白水平。未发现父母年龄对后代的白细胞谱、获得性免疫的体液成分、抗氧化酶活性或DNA损伤有影响。我们的研究结果表明，虽然年轻父母的雏鸟可能会经历更多的压力条件，但支持体细胞维持的整体机制可能会保护后代免受父母随着年龄增长而积累的分子损伤的跨代转移。我们的发现为长寿物种的亲代年龄效应的生理基础提供了新的见解。

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引用次数: 0

Glycogen synthase 2 knock-out zebrafish exhibit enhanced glucose metabolism in the liver 糖原合成酶2敲除斑马鱼在肝脏中表现出增强的葡萄糖代谢。

IF 2.2 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-12-13 DOI: 10.1016/j.cbpa.2025.111960

Keita Sameshima , Aya Yokose , Rei Yanagida , Yoshiki Sato , Yuta Suzuki , Makoto Kashima , Mayu Inokuchi , Otto Baba , Tatsuki Yoshinaga , Fumiya Furukawa

The liver is one of the major organs for glycogen storage and is essential for maintaining glucose homeostasis in the whole body. Glycogen synthesis in liver is regulated by the rate-limiting enzyme, glycogen synthase 2 (Gys2). In fish, however, the detailed roles of glycogen and Gys2 are poorly understood. In this study, we generated, for the first time, gys2 knock-out (gys2 −/−) zebrafish and evaluated the effects of impaired glycogen synthesis on physiological parameters of this fish. No effects on development or maturation were observed in gys2 −/− strain lacking Gys2. Periodic acid Schiff (PAS) staining, immunofluorescence staining with anti-glycogen antibody, and transmission electron microscopy (TEM) observations confirmed that glycogen synthesis does not occur in the gys2 −/− liver. Liquid chromatography-mass spectrometry (LC-MS/MS) metabolite analysis and isotope tracing revealed a marked increase in the activity of glucose metabolism and levels of related metabolites in the livers of adult gys2 −/−. Surprisingly, glucoamylase treatment released higher amount of glucose from gys2 −/− liver extract than that of the wild-type (WT) counterpart, suggesting the existence of putative compensatory or abberant glucose polymer, which might be caused by the elevated glucose metabolism in the gys2 −/− liver. Meanwhile, RNA-Seq analysis did not show increased expression levels of glucose metabolism–related genes consistent with the metabolic activity in gys2 −/− liver. These results suggest that liver Gys2 is dispensable in zebrafish, and enhanced glucose metabolism and putative backup mechanism to accumulate extra glucose may support the fish lacking Gys2.

肝脏是储存糖原的主要器官之一，对维持全身葡萄糖稳态至关重要。肝中的糖原合成受限速酶糖原合成酶2 （Gys2）的调控。然而，在鱼类中，糖原和Gys2的详细作用尚不清楚。在本研究中，我们首次生成gys2敲除（gys2-/-）斑马鱼，并评估糖原合成受损对该鱼生理参数的影响。在缺乏gys2的gys2-/-菌株中未观察到发育或成熟的影响。周期性酸希夫（PAS）染色、抗糖原抗体免疫荧光染色和透射电镜（TEM）观察证实，gys2-/-肝脏中不发生糖原合成。液相色谱-质谱（LC-MS/MS）代谢物分析和同位素示踪显示，成人gys2-/-的肝脏中葡萄糖代谢活性和相关代谢物水平显著增加。令人惊讶的是，与野生型（WT）相比，葡萄糖淀粉酶处理释放的gys2-/-肝脏提取物中的葡萄糖量更高，这表明可能存在代偿性或异常的葡萄糖聚合物，这可能是由gys2-/-肝脏中葡萄糖代谢升高引起的。同时，RNA-Seq分析未显示gys2-/-肝脏中与代谢活性一致的葡萄糖代谢相关基因表达水平升高。这些结果表明，肝脏Gys2在斑马鱼中是不可缺少的，葡萄糖代谢的增强和积累额外葡萄糖的备用机制可能支持缺乏Gys2的鱼类。

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引用次数: 0

The influence of light wavelength on HPA axis function in non-human animals: A meta-analysis 光波长对非人类动物下丘脑轴功能的影响：荟萃分析。

IF 2.2 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-12-11 DOI: 10.1016/j.cbpa.2025.111961

Isabella Robertson-Dixon, Melanie J. Murphy, Nina Riddell

The suprachiasmatic nucleus regulates circadian rhythms in physiological and behavioural processes partly through modulation of the hypothalamic–pituitary–adrenal (HPA) axis. The suprachiasmatic nucleus is entrained by light via input from intrinsically photosensitive retinal ganglion cells that are particularly sensitive to short wavelengths, theoretically linking light spectra to HPA axis function. This systematic review and meta-analysis evaluated the effects of wavelength of light on biochemical markers of the HPA axis in terrestrial non-human animals. A search of seven databases on 13 January 2025 identified 23 studies meeting inclusion criteria. Study subjects spanned a variety of animal species. Subjects were typically exposed to coloured light for the entire daytime light period for multiple weeks prior to HPA axis assessment. Corticosterone was the most frequently reported HPA axis measure. Melatonin, an additional hormonal index of circadian rhythms, was reported alongside corticosterone when data were available. Meta-analyses showed that in poultry, blue, blue-enriched, and red light rearing induced medium to large statistically non-significant increases in daytime corticosterone levels relative to white light, while green and UV-enriched light elicited weaker or inconsistent effects. In melatonin-proficient laboratory rodents, blue-enriched light induced a large significant decrease in daytime corticosterone and a large significant increase in nighttime melatonin. These findings highlight the importance of considering light wavelength for animal welfare and the optimisation of lighting conditions in research, agricultural, and ecological settings.

Registration: osf.io/rvu4w.

视交叉上核部分通过调节下丘脑-垂体-肾上腺轴来调节生理和行为过程中的昼夜节律。视交叉上核通过对短波特别敏感的视网膜神经节细胞的输入被光所携带，理论上将光谱与HPA轴功能联系起来。本系统综述和荟萃分析评估了光波长对陆生非人类动物下丘脑轴生化标志物的影响。2025年1月13日对7个数据库的检索确定了23项符合纳入标准的研究。研究对象涵盖了各种动物物种。在HPA轴评估之前，受试者通常在整个白天暴露在有色光下数周。皮质酮是最常报道的HPA轴测量。当数据可用时，褪黑激素（一种额外的昼夜节律激素指数）与皮质酮一起被报道。荟萃分析显示，在家禽中，蓝光、富蓝光和红光饲养诱导的白天皮质酮水平相对于白光有中等到较大的统计学上不显著的增加，而绿光和富紫外线光引起的影响较弱或不一致。在精通褪黑素的实验室啮齿类动物中，富含蓝光的光导致白天皮质酮显著下降，夜间褪黑激素显著增加。这些发现强调了在研究、农业和生态环境中考虑光波长对动物福利和优化照明条件的重要性。注册:osf.io / rvu4w。

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引用次数: 0

Effects of heat stress on HSP70 and Na+/K+-ATPase expressions in the gills of juvenile goldfish: Focus on tissue architecture, mucus secretion and protein nitration 热应激对金鱼幼鱼鳃中HSP70和Na+/K+- atp酶表达的影响：重点关注组织结构、粘液分泌和蛋白质硝化。

IF 2.2 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-12-09 DOI: 10.1016/j.cbpa.2025.111959

Ngozichukwu Francis Ngozichukwu , Md Saydur Rahman

Global warming has worsened heat stress on aquatic habitats, creating physiological challenges for ectothermic animals such as teleost fish. The fish gill, a multifunctional organ responsible for gas exchange and osmoregulation, is especially vulnerable to environmental stress. This study examined how elevated temperatures affect the gills of juvenile goldfish (Carassius auratus) under simulated climate conditions. Fish were exposed to control (22 °C), medium (28 °C), and high (32 °C) temperature settings for two weeks. Histological evaluations showed significant structural changes, including lamellar fusion, epithelial detachment, and edema in the high-temperature groups, indicating tissue injury and decreased function. Immunohistochemical and real-time qRT-PCR analyses revealed notable alterations in key stress biomarkers following heat exposure. Heat shock protein 70 (HSP70, a chaperone protein) expression and mRNA levels increased significantly (P<0.05) during heat stress, suggesting activation of cellular defense against protein denaturation. Additionally, higher expression of 3-nitrotyrosine protein, a marker of protein nitration, indicated nitrative stress likely caused by excess reactive nitrogen species during heat stress. The expression and mRNA levels of Na⁺/K⁺-ATPase, an enzyme in ion regulation, were significantly reduced (P<0.05) in the gills of heat-stressed fish, indicating compromised osmoregulatory ability. These findings suggest that fish gills show unique morphological and molecular responses to elevated temperature, highlighting their sensitivity as early indicators of heat stress. They also show how nitrative stress arises from high temperatures and underscore the broader ecological impacts of climate change on teleost species. Understanding these biological and molecular responses are essential for developing models to predict the effects of global climate change.

全球变暖加剧了水生栖息地的热应激，给硬骨鱼等恒温动物带来了生理上的挑战。鱼的鳃是一个负责气体交换和渗透调节的多功能器官，特别容易受到环境压力的影响。本研究考察了在模拟气候条件下，高温如何影响幼金鱼（Carassius auratus）的鳃。将鱼置于对照（22°C）、中温（28°C）和高温（32°C）环境中两周。组织学评价显示，高温组组织结构发生明显变化，包括板层融合、上皮脱离和水肿，表明组织损伤和功能下降。免疫组织化学和实时qRT-PCR分析显示，热暴露后关键应激生物标志物发生了显著变化。热休克蛋白70 （HSP70，一种伴侣蛋白）的表达和mRNA水平显著升高（P+/K+- atp酶，一种离子调节酶）

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引用次数: 0

Evaluating bioelectrical impedance analysis (BIA) as a tool for assessing freshwater fish condition 评价生物电阻抗分析（BIA）作为评估淡水鱼状况的工具

IF 2.2 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-11-26 DOI: 10.1016/j.cbpa.2025.111958

Maxwell C. Mallett , Jason D. Thiem , Gavin L. Butler , Luke Carpenter-Bundhoo , Curtis Champion , Mark J. Kennard

The nutritional status, or condition, of fish is a key health proxy influencing vital life history processes including migration, reproduction, and recruitment. Numerous morphological, biochemical, and electronic metrics are used to assess fish condition, yet it remains unclear if these metrics are congruent with each other and across species. This study evaluates bioelectrical impedance analysis (BIA) as a tool for assessing fish condition by comparing it with morphological (e.g. condition index, hepatosomatic index) and biochemical (e.g. percentage and total-body mass compositions of lipid, mineral, protein and water content and bulk C:N ratios in muscle tissue) condition metrics in three native Australian fish species (Macquaria ambigua, Nematalosa erebi, and Percalates novemaculeata) and one invasive species (Cyprinus carpio). Using simple least-squares linear regressions and Principal Component Analysis (PCA), we uncovered that BIA parameters correlated strongly with total-body masses of biochemical components that covary with body size, but showed weaker correlations with percentage compositions of the same components. However, phase angle, a common BIA measure, showed some significant correlations with morphological condition and lipid content, although these relationships were generally weak and species dependent. These findings suggest that BIA can effectively estimate certain physiological parameters, but caution should be applied when interpreting BIA metrics, as their relationship with established indicators of condition may vary. The current study underscores the importance of combining multiple methods to provide a comprehensive understanding of fish condition in freshwater ecosystems, which can be used to provide mechanistic linkages with anthropogenic impacts.

鱼类的营养状况是影响重要生活史过程（包括洄游、繁殖和繁殖）的关键健康指标。许多形态学、生化和电子指标被用来评估鱼类的状况，但这些指标是否彼此一致以及跨物种是否一致仍不清楚。本研究通过比较三种澳大利亚本地鱼类（Macquaria ambigua、Nematalosa erebi和Percalates novemaculeata）和一种入侵物种（Cyprinus carpio）的形态学（如状态指数、肝体指数）和生化（如脂肪、矿物质、蛋白质和水分的百分比和总质量组成以及肌肉组织中的体积C:N比率）状态指标，对生物电阻抗分析（BIA）作为评估鱼类状态的工具进行了评估。利用简单最小二乘线性回归和主成分分析（PCA），我们发现BIA参数与随体型变化的生化成分的总质量有很强的相关性，但与相同成分的百分比组成的相关性较弱。然而，作为BIA常用的测量指标，相位角与形态状况和脂质含量有显著的相关性，尽管这些关系通常较弱且依赖于物种。这些发现表明，BIA可以有效地估计某些生理参数，但在解释BIA指标时应谨慎，因为它们与既定条件指标的关系可能会有所不同。目前的研究强调了将多种方法结合起来对淡水生态系统中鱼类状况的全面了解的重要性，这可以用来提供与人为影响的机制联系。

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引用次数: 0

Acclimation to moderate hypoxia improves acute hypoxia tolerance of diploid and triploid brook charr, Salvelinus fontinalis 适度缺氧驯化可提高二倍体和三倍体丹参的急性缺氧耐受性

IF 2.2 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-11-26 DOI: 10.1016/j.cbpa.2025.111957

Sarah A. McGeachy, Tillmann J. Benfey

Triploid salmonids are used in aquaculture and stocking programs for recreational fishing because they are reproductively sterile and therefore cannot breed in the wild. However, they appear to be more sensitive than diploids to environmental stressors. The objective of this study was to develop a better understanding of the hypoxia tolerance of triploids. We compared the acute hypoxia tolerance of sibling diploid and triploid brook charr that were acclimated to either moderate hypoxia (65 % of air saturation) or normoxia (98 % air saturation). Fish then underwent acute hypoxia trials, by slowly injecting nitrogen gas to displace oxygen and using loss of equilibrium (LOE) as the endpoint. The fish acclimated to moderate hypoxia had a lower oxygen tension (PO₂) at LOE compared to fish acclimated to normoxia, regardless of ploidy. Ploidy did not affect time to LOE, but triploids had a higher PO₂ at LOE (i.e., were less tolerant of acute hypoxia) compared to diploids. Potential predictors of acute hypoxia tolerance (hematocrit, blood glucose, blood lactate, relative ventricular mass, hepatosomatic index, condition factor, compact myocardium thickness, and interlamellar cell mass) did not provide conclusive results. However, relative interlamellar cell mass size was larger in triploids, suggesting reduced functional gill surface area for respiratory gas exchange as a possible explanation for their reduced acute hypoxia tolerance. This study has shown the capacity for moderate hypoxia acclimation to improve triploid performance, although not to the same extent as for diploids.

三倍体鲑鱼被用于水产养殖和休闲钓鱼的放养计划，因为它们是生殖不育的，因此不能在野外繁殖。然而，它们似乎比二倍体对环境压力更敏感。本研究的目的是为了更好地了解三倍体的耐缺氧性。我们比较了兄弟二倍体和三倍体小溪鲑的急性缺氧耐受性，它们分别适应中度缺氧（65%的空气饱和度）和常氧（98%的空气饱和度）。然后进行急性缺氧试验，通过缓慢注射氮气来取代氧气，并以平衡损失（LOE）为终点。无论倍性如何，适应中度缺氧的鱼在LOE时的氧张力（PO2）低于适应正常缺氧的鱼。倍性不影响到达LOE的时间，但与二倍体相比，三倍体在LOE时的PO2较高（即对急性缺氧的耐受性较差）。急性缺氧耐受性的潜在预测因子（红细胞比容、血糖、血乳酸、相对心室质量、肝体指数、病情因子、致密心肌厚度和层间细胞质量）没有提供结结性结果。然而，三倍体的相对层间细胞质量更大，表明用于呼吸气体交换的功能鳃表面积减少可能是其急性缺氧耐受性降低的原因。本研究表明，适度缺氧驯化能够提高三倍体的性能，尽管程度不如二倍体。

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引用次数: 0

The effects of tidally changing salinities on branchial tight junction protein gene expression in tilapia 盐度潮汐变化对罗非鱼鳃紧密连接蛋白基因表达的影响。

IF 2.2 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-11-23 DOI: 10.1016/j.cbpa.2025.111956

G.H.T. Malintha , Ke Cao , Fritzie T. Celino-Brady , Jason P. Breves , Andre P. Seale

To maintain hydromineral balance during transitions between different environmental salinities, euryhaline teleosts adjust the permeability characteristics of their surface epithelia to align with ambient conditions. Tight junctions (TJs), which form the apical-lateral barriers between epithelial cells, control the paracellular movement of solutes and water. Consequently, euryhaline species must efficiently reorganize branchial TJs when acclimating to freshwater (FW) and seawater (SW) environments. However, little is known about how TJs are regulated under tidally changing salinities. In the current study, we employed RNA-Seq to identify several branchial TJ transcripts that are differentially expressed in Mozambique tilapia (Oreochromis mossambicus) acclimated to FW, SW, or a tidal regime (TR). The most abundant and differentially expressed TJ transcripts, which included claudins (cldn-4 like, cldn7b, cldn23a, and cldn-like ZF-A89), occludins (oclna and oclnb), and TJ proteins (tjp1a and tjp3), were further investigated by qPCR. Generally, the expression of TJ transcripts varied to a greater extent between the FW and SW phases of the TR (denoted TF and TS, respectively) than between steady-state FW and SW conditions. Furthermore, TJ transcripts were usually upregulated in TF compared to TS or SW controls. In contrast, the gene expression of branchial ion transporters did not change as markedly under a TR. Together, these results suggest that TJs play a crucial role in regulating the permeability of branchial epithelia by preventing ion loss in hyposmotic conditions, particularly during short-term tidally changing salinities.

为了在不同环境盐度之间的过渡期间维持水矿物平衡，泛盐硬骨鱼调整其表面上皮的渗透性特征以适应环境条件。紧密连接（TJs）在上皮细胞间形成顶侧屏障，控制着溶质和水的胞外运动。因此，在适应淡水（FW）和海水（SW）环境时，泛盐物种必须有效地重组鳃TJs。然而，对于TJs在潮汐变化的盐度下是如何调节的，我们知之甚少。在当前的研究中，我们采用RNA-Seq技术鉴定了几种在适应FW、SW或潮汐（TR）的莫桑比克罗非鱼（Oreochromis mossambicus）中差异表达的鳃TJ转录本。通过qPCR进一步研究了最丰富和差异表达的TJ转录本，包括cldn-4样、cldn7b、cldn23a和cldn样ZF-A89)、occludins （oclna和oclnb）和TJ蛋白（tjp1a和tjp3）。总的来说，TJ转录本在TR的FW期和SW期（分别记为TF和TS）的表达差异大于稳态FW和SW条件下的表达差异。此外，与TS或SW对照相比，TF中的TJ转录本通常上调。相比之下，在TR条件下，鳃离子转运体的基因表达没有明显变化。总之，这些结果表明，TJs在低渗条件下，特别是在短期潮汐变化的盐度下，通过防止离子损失，在调节鳃上皮通透性方面起着至关重要的作用。

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引用次数: 0

Context-dependent relationships between metabolism and behavior across temperature acclimations in sheepshead minnows (Cyprinodon variegatus) 在温度适应过程中，羊头鲦鱼的代谢和行为之间的环境依赖关系。

IF 2.2 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-11-17 DOI: 10.1016/j.cbpa.2025.111952

Madison Schumm, Kerri L. Ackerly, Andrew J. Esbaugh

Marine fish are able to cope with environmental changes through altering their physiology and behavior. Among environmental stressors, thermal stress is particularly relevant for fish because increased temperature leads to elevated baseline metabolic costs and also has known impacts on behavior. The Performance Model provides a conceptual framework linking metabolism and behavior such that individual differences in baseline metabolic demand influence behavioral expression specifically related to acquiring resources that support metabolic machinery. Thus, under warming, increased energy demand should lead to increased risk-taking and lower behaviors that deter predation (e.g., shoaling and scototaxis). On this background, our objective was to assess behavioral and metabolic responses to warming and the relationship these traits across two temperatures in an estuarine model teleost, the sheepshead minnow (Cyprinodon variegatus). Fish were exposed to 22 °C or 32 °C for 14-days and standard metabolic rate (SMR) was measured. Each fish was subsequently tested in a series of behavioral assays to assess activity, exploration, sociability, and anxiety-like behavior. As anticipated, warmer temperatures increased in SMR and increased activity while reducing anxiety-like behavior. However, relationships between behavior and metabolism were present only in control conditions and, composite behavioral scores indicated negative relationships in in the opposite direction of predictions based on the performance model. Interestingly, trait patterns dissipated under warming suggesting that predictions based on models in control conditions may have dubious utility under climate change. We argue that behavioral-metabolic relationships are sensitive to context, and environmental factors should be considered when exploring the intersection between behavior and physiology.

海洋鱼类能够通过改变生理和行为来应对环境变化。在环境压力因素中，热应激对鱼类尤为重要，因为温度升高会导致基线代谢成本升高，并对行为产生已知影响。性能模型提供了一个将代谢和行为联系起来的概念框架，这样，基线代谢需求的个体差异会影响与获取支持代谢机制的资源具体相关的行为表达。因此，在气候变暖的情况下，能源需求的增加将导致冒险行为的增加和阻止捕食行为的减少（例如，浅滩和滑行）。在此背景下，我们的目标是评估行为和代谢对变暖的反应，以及这些特征在两种温度下的关系，在河口模型硬骨鱼，羊头鲦鱼（Cyprinodon variegatus）。将鱼暴露在22 °C或32 °C环境中14天，并测量标准代谢率（SMR）。随后，每条鱼都接受了一系列行为测试，以评估它们的活动、探索、社交能力和焦虑样行为。正如预期的那样，温暖的温度增加了SMR，增加了活动，同时减少了焦虑样行为。然而，行为和代谢之间的关系仅在控制条件下存在，并且，综合行为评分显示与基于性能模型的预测相反方向的负相关。有趣的是，性状模式在变暖下消散，这表明基于控制条件下模型的预测在气候变化下可能具有可疑的效用。我们认为，行为-代谢关系对环境敏感，在探索行为和生理学之间的交集时应考虑环境因素。

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Heat shock protein 70 expression in the skin of Pelophylax bergeri in response to thermal stress 热休克蛋白70在柏草表皮对热应激的表达。

IF 2.2 3区生物学 Q4 BIOCHEMISTRY & MOLECULAR BIOLOGY

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology

Pub Date : 2025-11-16 DOI: 10.1016/j.cbpa.2025.111955

Francesca Simoncelli , Ines Di Rosa , Anna Fagotti

The amphibian skin is an organ of interest as an indicator of the cellular response to stress factors. The upregulation of Heat Shock Proteins (HSPs) is an important step in the cellular defense mechanisms against various endogenous and exogenous stressors. In this preliminary note, we investigated the expression of the inducible Hsp70 as a marker of thermal stress in the skin of the anuran Pelophylax bergeri. RT-qPCR analysis revealed that there was an elevated upregulation in the expression levels of Hsp70 after short-term heat stress. The immunolocalization of Hsp70 on skin samples shocked at 33 °C, showing the highest gene induction, revealed a positive staining in both epithelial and connective skin cells. These results indicate that Hsp70 could be a potential player in the skin defense mechanism. This study might contribute to a better understanding of the stress response in amphibians against thermal shock.

两栖动物的皮肤是一个有趣的器官，作为细胞对应激因素反应的指标。热休克蛋白的上调是细胞防御各种内源性和外源性应激源的重要步骤。在这篇初步的论文中，我们研究了作为热胁迫标志的诱导型Hsp70在牛油蕨皮肤中的表达。RT-qPCR分析显示，短期热应激后Hsp70表达水平上调。在33 °C下，Hsp70在皮肤样品上的免疫定位表现出最高的基因诱导，在上皮细胞和结缔组织细胞中均呈阳性染色。这些结果表明，Hsp70可能是皮肤防御机制的潜在参与者。这项研究可能有助于更好地理解两栖动物对热休克的应激反应。

引用次数: 0