Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology最新文献

{"title":"Integrated analysis of antioxidant defense and energy metabolism in the gills of Sinonovacula constricta under hyposalinity stress","authors":"Yuting Han ,&nbsp;Kai Ye ,&nbsp;Geqi Gao ,&nbsp;Jinxu Guo ,&nbsp;Ming Shan ,&nbsp;Donghong Niu","doi":"10.1016/j.cbpa.2025.111932","DOIUrl":"10.1016/j.cbpa.2025.111932","url":null,"abstract":"<div><div>Salinity has a significant impact on the growth, energy metabolism, and immune regulation of marine bivalves. To elucidate the response of marine bivalves to low salinity environments and their tolerance mechanisms, this study investigated histopathological alterations and measured oxidative stress indicators along with energy metabolism parameters in gill tissues of <em>Sinonovacula constricta</em> under hyposalinity stress (salinity 5). Transcriptomic profiling of gills from the control group (salinity 20) and low salinity group was concurrently analyzed. The results demonstrated that during the initial stress phase, the antioxidant defense system was activated, evidenced by significant increases in superoxide dismutase (SOD) and catalase (CAT) activities as well as total antioxidant capacity (T-AOC). Concurrently, elevated levels of reactive oxygen species (ROS) and malondialdehyde (MDA) indicated oxidative stress status. In the later stress phase, declined activities of antioxidant enzymes suggested severe oxidative damage. Throughout hyposalinity exposure, ATP content progressively decreased, while ATPase and pyruvate kinase (PK) activities exhibited an initial increase followed by reduction, reflecting elevated energy expenditure. Transcriptomic analysis identified 501 differentially expressed genes (DEGs) between low salinity and control groups. GO and KEGG enrichment analyses revealed significant enrichment of these DEGs in energy metabolism and protein synthesis-related processes, with notable enrichment in functional enzyme activities associated with the phosphatidylinositol signaling pathway in gills. This study systematically revealed the physiological response mechanisms of <em>S. constricta</em> to hyposalinity stress, and elucidated the roles of the phosphatidylinositol signaling pathway, amino acid metabolism, and endoplasmic reticulum protein processing in the adaptation of <em>S. constricta</em> to hyposalinity stress.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"310 ","pages":"Article 111932"},"PeriodicalIF":2.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145088394","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}

{"title":"Up-regulation of cell apoptosis, autophagy and mitochondrial dynamics in ovarian granulosa cells of Daurian ground squirrels during the pre-hibernation period","authors":"Xi Wang ,&nbsp;Hao Li ,&nbsp;Zhaomei Dong ,&nbsp;Wenjing Lu ,&nbsp;Jirui Chen ,&nbsp;Haolin Zhang ,&nbsp;Zhengrong Yuan ,&nbsp;Yuning Liu ,&nbsp;Qiang Weng ,&nbsp;Yingying Han","doi":"10.1016/j.cbpa.2025.111927","DOIUrl":"10.1016/j.cbpa.2025.111927","url":null,"abstract":"<div><div>Daurian ground squirrel (<em>Spermophilus dauricus</em>) exhibits both seasonal breeding and hibernation characteristics, but the adaptive changes in ovaries during the transition from seasonal reproduction to hibernation remain poorly understood. The aim of this study is to investigate the regulatory characteristics of granulosa cell apoptosis, autophagy and mitochondrial dynamics in the ovaries of wild Daurian ground squirrels across the April (breeding period), June (non-breeding period), and September (non-breeding and pre-hibernation period). The results proved that ovarian weight, as well as serum reproductive hormones, significantly decreased in June and September compared with April. Interestingly, unlike in June, many growing antral follicles emerged in the ovaries of wild Daurian ground squirrels during September. Furthermore, the molecular studies revealed a significant increase in ovarian gene expression related to cell apoptosis (<em>Casp3, Bax/Bcl-2</em>), autophagy (<em>Becn1, Pink1, Parkin, Sqstm1</em>) and mitochondrial dynamics (<em>Mfn1, Mfn2, Drp1</em>) during September compared to June. Additionally, immunohistochemical results indicated that the protein levels of the aforementioned genes and LC3A/B were concurrently upregulated, predominantly located in ovarian granulosa cells. Consistently, comparative analysis of ovarian transcriptomic data across different periods further confirmed that genes differentially expressed during the three periods were enriched in pathways related to apoptosis, autophagy, and mitochondrial dynamics. In summary, these results revealed a significant up-regulation of cell apoptosis, autophagy, and mitochondrial dynamism in ovarian granulosa cells of wild ground squirrels during the pre-hibernation period, may play a critical role in ovarian development for hibernation and subsequent stage.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"310 ","pages":"Article 111927"},"PeriodicalIF":2.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145042473","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}

{"title":"Effects of α-dicarbonyl compounds on cell viability in chicken myoblasts","authors":"Meiko Okino ,&nbsp;Ryosuke Makino ,&nbsp;Tetsuya Tachibana","doi":"10.1016/j.cbpa.2025.111937","DOIUrl":"10.1016/j.cbpa.2025.111937","url":null,"abstract":"<div><div>Alpha-dicarbonyl compounds (α-DCs), such as glyoxal (GO) and methylglyoxal (MGO), are highly reactive compounds produced from glucose through various chemical reactions. Diabetic patients with chronic hyperglycemia exhibit higher blood concentrations of GO and MGO than healthy individuals. GO and MGO are cytotoxic to various mammalian cells and are associated with diabetic complications. Given that chickens are hyperglycemic animals, they would possess high levels of GO and MGO in their blood. However, the cytotoxic effects of GO and MGO have not been elucidated in chicken cells. The purpose of the present study was to clarify the effects of GO and MGO on the viability of chicken myoblasts. The two α-DCs decreased the level of intracellular nicotinamide adenine dinucleotide (reduced form), which is an indicator of cell viability, cell proliferation, and energy metabolism. However, neither of the two α-DCs induced apoptotic cell death, production of reactive oxygen species, or lipid peroxidation. In addition, GO and MGO did not induce mitochondrial dysfunction. The present study demonstrated that GO and MGO would have adverse effects on myogenesis in chickens.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"310 ","pages":"Article 111937"},"PeriodicalIF":2.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145214523","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}

{"title":"Time-course of mRNA abundance of appetite-regulatory genes in the brain of rainbow trout fed a plant-based diet from the first feeding","authors":"Cristina Fernández-Maestú ,&nbsp;Maud Martinat ,&nbsp;Jessica Calo ,&nbsp;Cristina Velasco ,&nbsp;José L. Soengas ,&nbsp;Jérôme Roy ,&nbsp;Ayelén M. Blanco","doi":"10.1016/j.cbpa.2025.111939","DOIUrl":"10.1016/j.cbpa.2025.111939","url":null,"abstract":"<div><div>The early developmental stages of fish are critical for improving feeding strategies and growth performance. Understanding feeding-regulatory mechanisms from the earliest stages of development is crucial, especially in the context of aquaculture, where early nutrition has a significant impact on feeding behaviour, growth and survival. This is particularly relevant in carnivorous species, such as rainbow trout (<em>Oncorhynchus mykiss</em>), where the complete replacement of fishmeal and fish oil with plant-based ingredients has negative effects on growth performance and early stage survival. This study investigates the time-course of mRNA abundance of genes encoding key appetite-regulatory neuropeptides and integrative signalling pathways from first feeding to 100 days post-feeding with either a commercial-like diet containing fishmeal and fish oil or a plant-based diet devoid of these marine-derived ingredients. Results showed that an initial diet based on plants does not notably affect the levels of mRNA for appetite-regulating neuropeptides in the brain of rainbow trout alevins. However, the plant-based diet induced slightly distinct patterns in gene mRNA abundance after the first meal, which may underpin reduced feed intake and growth performance. Some key appetite-regulatory neuropeptides, such as neuropeptide Y (<em>npy</em>) and cocaine- and amphetamine-regulated transcript (<em>cartpt</em>), exhibited progressive higher levels in the brain over time, while agouti-related protein 1 (<em>agrp1</em>) and pro-opiomelanocortin a1 (<em>pomca1</em>) levels decreased following initial feeding. Moreover, the expression of key integrative signalling components, including AMP-activated kinase α2 (<em>pkraa2</em>), mechanistic target of rapamycin (<em>mtor</em>), cAMP response-element binding protein 1 (<em>creb1</em>), and forkhead box O1 (<em>foxo1</em>), increased throughout growth, but their abundance was modulated differently by the dietary treatments. This study underscores the importance of understanding neuroendocrine responses to dietary formulations for optimizing aquafeeds and enhancing sustainability in aquaculture.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"310 ","pages":"Article 111939"},"PeriodicalIF":2.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145253672","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}

{"title":"Reproductive gene expression in female broodstock European flat oyster, Ostrea edulis, under ambient and constant temperature and photoperiod regimes","authors":"Mairi E. Cowan ,&nbsp;Eduardo Jimenez-Fernandez ,&nbsp;Aaliyah Malla ,&nbsp;Adam D. Hughes","doi":"10.1016/j.cbpa.2025.111934","DOIUrl":"10.1016/j.cbpa.2025.111934","url":null,"abstract":"<div><div>The European flat oyster (<em>Ostrea edulis</em>) is a species of significant ecological, commercial and cultural importance. Interest in scaling up its production is growing rapidly, however, challenges in managing reproduction in culture remain. This study aimed to improve understanding of reproductive control in female broodstock by analysing the gene expression of the key endocrine factors APGWamide, GnRH (gonadotropin releasing hormone) and GPB5 in the visceral ganglion, as well as vitellogenin in the gonads. This was performed alongside histological classification of individuals by sex and reproductive stage. Oysters were subjected to three different conditioning regimes: a reference regime consisting of ambient temperature and a long-day photoperiod of 18-h light: 6-h dark (REF(Amb/18:6)), and separately, two constant temperature regimes of 14 °C, either under simulated natural photoperiod (14C/NP) or constant 24-h light (14C/LL). Histology revealed a female-to-male shift across regimes. Gametogenesis progressed under all conditions, but females under constant light (14C/LL) showed less uniform development. <em>Apgwamide</em> expression significantly increased as females developed across all regimes. <em>Vitellogenin</em> expression also significantly increased over time and with gametogenesis under the REF(Amb/18:6) and 14C/NP regimes. No clear patterns were observed for <em>gnrh</em> and <em>gpb5</em> expression in this dataset, though their roles in reproduction cannot be excluded. Altogether, these findings support APGWamide and vitellogenin as key factors of interest in female reproduction, with light, as well as the known effects of temperature, influencing development. This research provides insights to support broodstock conditioning and European flat oyster production and restoration efforts.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"310 ","pages":"Article 111934"},"PeriodicalIF":2.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145182388","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}

{"title":"Hypoxia and reoxygenation induced distinct patterns of response in antioxidant capacity between two cyprinid fish species","authors":"Qing-lin Cao,&nbsp;Shi-jian Fu,&nbsp;Yu-tong Hou,&nbsp;Shuai Yang,&nbsp;Zhong-hua Tang","doi":"10.1016/j.cbpa.2025.111928","DOIUrl":"10.1016/j.cbpa.2025.111928","url":null,"abstract":"<div><div>Antioxidant defense represents a critical biological capacity enabling organisms to counteract homeostasis disruption and mitigate oxidative stress induced by environmental stressors, such as oxygen fluctuations. However, comparative studies investigating the differential responses of antioxidant defense systems to oxygen fluctuations across diverse animal species remain limited. In the present study, two common cyprinid species—common carp (<em>Cyprinus carpio</em>) and Chinese hook snout carp (<em>Opsariichthys bidens</em>)—maintained under normoxic conditions (&gt; 7 mg L⁻¹ O₂) were exposed to hypoxia (1.04 ± 0.2 mg L⁻¹ O₂) for 3 h, followed by a 3-h reoxygenation period (&gt; 7 mg L⁻¹ O₂). A comparative analysis of key enzymes within the classical enzymatic antioxidant system was subsequently performed. The results demonstrated that the total protein (TP) concentration in the liver, brain and gill of both fish species was significantly altered under hypoxic and/or reoxygenation conditions. In common carp, hepatic superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) activity, cerebral SOD, catalase (CAT) and glutathione peroxidase (GPx) activity, as well as branchial CAT and GPx activity, were significantly elevated during the hypoxic period. Except for hepatic SOD activtiy, which remained elevated during reoxygenation, these parameters recovered to control levels. These findings support the preparation for oxidative stress (POS). However, in Chinese hook snout carp, hepatic CAT and GPx activity, as well as branchial GPx and T-AOC activity, exhibited a distinct decreasing trend during hypoxia, followed by recovery to control levels during reoxygenation. Furthermore, cerebral SOD, T-AOC activity, along with branchial SOD activity, remained unchanged under hypoxic conditions but increased significantly during reoxygenation. These responses did not align with the POS strategy. The malondialdehyde (MDA) content remained stable or decreased in both tested fish species during hypoxia and reoxygenation, except for an increase in MDA levels under hypoxic conditions. The result indicates that neither species experienced oxidative damage. These results suggest that the common carp tends to employ a proactive strategy to cope with environmental stress. The tendency may be associated with its frequent exposure to adverse environmental conditions, which has likely facilitated the development of enhanced hypoxia tolerance and the capacity to anticipate future stressors. In contrast, the Chinese hook snout carp, which exhibits lower hypoxia-tolerant, inhabits rapid-flowing habitats where dissolved oxygen concentrations remain relatively high and stable. This has suppressed the development of capacities for predict future changes in environmental stressors.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"310 ","pages":"Article 111928"},"PeriodicalIF":2.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145058773","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}

{"title":"Seasonality effects on the inflammatory and antioxidant responses in the gilthead seabream (Sparus aurata)","authors":"Vasiliki Makri ,&nbsp;Konstantinos Feidantsis ,&nbsp;Ioannis A. Giantsis ,&nbsp;Ioannis Georgoulis ,&nbsp;Cosmas Nathanailides ,&nbsp;Basile Michaelidis","doi":"10.1016/j.cbpa.2025.111938","DOIUrl":"10.1016/j.cbpa.2025.111938","url":null,"abstract":"<div><div>Mediterranean fish such as <em>Sparus aurata</em> are subjected to extremes of high and low temperature favored by climate change effects, resulting to increased oxidative stress and inflammatory responses. To explore these phenomena, <em>tnf-a</em> and <em>nfkb</em> gene expression, as well as TNF-α and IL-6 levels were evaluated regarding inflammation, while sod, cat and gr gene expression, as well as SOD, GR and catalase activity levels were measured to assess antioxidant response. Findings revealed distinct tissue specific responses, dividing acclimatization phase into distinct cold and warm patterns. In highly vascular tissues (heart and red muscle) increased inflammatory levels were observed at increasing sea water temperatures, highlighting seasonality's strong oxidative effect, which cannot be ameliorated by the increased antioxidant enzymatic response. However, the decreased expression of the antioxidant genes during this period probably highlights energy allocation for processes other than antioxidant defense. An opposite pattern was exhibited in the white muscle and the liver, following the temperature pattern, with lowering levels with decreasing temperatures, probably showing a metabolic depression during decreased temperatures, and an increasing trend (mostly regarding antioxidant defense) during warming. These adjustments enlighten the adaptive responses of fish which reflect fluctuations of seasonal temperature, and the underlying thermal tolerance mechanisms during exposure to seasonal environmental oxidative stress. Understanding these responses helps scientists learn how fish cope with climate-related stress, which is important for managing fish populations and supporting sustainable aquaculture in a warming world.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"310 ","pages":"Article 111938"},"PeriodicalIF":2.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145214499","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}

{"title":"Bovine serum albumin and caffeine enhance activation of sperm from the American toad (Anaxyrus americanus)","authors":"Renato E. Naranjo ,&nbsp;Andy J. Kouba ,&nbsp;Terri L. Roth ,&nbsp;Carrie K. Kouba","doi":"10.1016/j.cbpa.2025.111942","DOIUrl":"10.1016/j.cbpa.2025.111942","url":null,"abstract":"<div><div>The collection and cryopreservation of anuran spermic urine results in multiple osmolality shifts that inactivate and reactivate sperm motility prior to in-vitro fertilization. These shifts in osmolality reduce motility recovery and fertilization potential. Here, we analyzed the effects of metabolic supplements for reactivation of sperm motility and forward progression from the American toad (<em>Anaxyrus americanus)</em>. Male toads (<em>n</em> = 30) were administrated hormones to stimulate spermiation and samples were mixed 1:1 with 2× simplified amphibian ringers solution for sperm inactivation. Inactivated sperm samples were randomly assigned to five treatment groups to be reactivated in distilled water alone (control) or supplemented with BSA (0.1 %, 0.2 %, 0.4 %), caffeine (1, 10, 25 mM), sodium pyruvate (0.5, 1, 2 mM), sodium lactate (10, 20, 40 mM), or sodium bicarbonate (10, 20, 40 mM). Sperm samples were assessed for total motility (TM) and quality of forward progressive movement (QFPM) at 0, 5, 15, 30, 45, 60, 90, and 120 min after reactivation. Results showed that sperm activated with BSA produced higher (<em>P</em> &lt; 0.05) recovered motility than the control, regardless of BSA concentration. Moreover, the addition of caffeine (1 mM) resulted in higher (<em>P</em> &lt; 0.05) sperm QFPM following reactivation compared to the control. In contrast, bicarbonate and lactate treatments resulted in lower recovery of TM and QFPM, while pyruvate had no effect (<em>P</em> ≥ 0.05). Our findings highlight the efficacy of BSA and caffeine on enhancing sperm motility and forward progression, respectively, following inactivation and reactivation of sperm undergoing short-term storage or cryopreservation procedures.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"310 ","pages":"Article 111942"},"PeriodicalIF":2.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145314313","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}

{"title":"Temperature drives the pace, not the price, of postprandial growth in Burmese pythons (Python bivittatus)","authors":"Katja B. Last,&nbsp;Terese Bech Eriksen,&nbsp;Emil Rindom,&nbsp;Tobias Wang","doi":"10.1016/j.cbpa.2025.111933","DOIUrl":"10.1016/j.cbpa.2025.111933","url":null,"abstract":"<div><div>Body temperature influences all physiological processes in ectotherms, including the rise in metabolism upon feeding (SDA response). In reptiles, elevated temperatures increase the magnitude of the SDA response but shorten its duration with total energy expenditure remaining unaffected. Recent studies show that feeding induces a several-fold elevation of protein synthesis in various organs of pythons, but the effects of temperature on postprandial protein synthesis remain unexplored. We therefore measured relative changes in postprandial protein synthesis in skeletal muscle and visceral organs of the Burmese pythons (<em>Python bivittatus</em>) as well as the rate of oxygen consumption (V̇O₂) and mass of selected organs at 25 and 35 °C. Measurement were made at the peak of the SDA response (72 and 24 h post feeding at 25 and 35 °C, respectively). Protein synthesis was assessed from the rate of puromycin-incorporation and V̇O₂ was measured with closed respirometry. As expected, V̇O₂ increased with temperature in both fasted and digesting snakes. Feeding induced a several fold rise in protein synthesis, with higher rates at 35 compared to 25 °C in most tissues, but mass specific organ masses were similar between fed snakes at both temperatures. This supports the concept that SDA represents the energetic cost of growth, resulting in the same level of growth is achieved over a shorter period for the 35 °C group compared to the 25 °C group. Moreover, the strong correlation between organ-specific protein synthesis and V̇O₂ further reinforces this concept. Our results demonstrate that elevated temperature accelerates postprandial protein synthesis without changing total growth, suggesting that temperature effects on the SDA response are primarily mediated by changes in the rate of protein synthesis.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"310 ","pages":"Article 111933"},"PeriodicalIF":2.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145151622","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}

{"title":"Growth hormone modulates epithelial intercellular junctions structure and intestinal permeability in zebrafish","authors":"Marcela G. Meirelles ,&nbsp;Camila I.M. Fénero ,&nbsp;Bruna F. Nornberg ,&nbsp;Tony L.R. da Silveira ,&nbsp;Mateus T. Kütter ,&nbsp;Niels Olsen S. Camara ,&nbsp;Luis Fernando Marins","doi":"10.1016/j.cbpa.2025.111936","DOIUrl":"10.1016/j.cbpa.2025.111936","url":null,"abstract":"<div><div>Intestinal permeability refers to the regulated passage of luminal contents into the internal milieu via transcellular or paracellular routes. Tight junctions (TJs), components of the apical junctional complex (AJC), are critical determinants of paracellular permeability and intestinal barrier integrity. Disruptions in growth hormone (GH) signaling have been implicated in gastrointestinal dysfunction; however, the effects of chronically elevated GH levels on intestinal barrier function remain poorly understood. In this study, we investigated whether GH overexpression affects intestinal permeability and epithelial structure using a transgenic zebrafish model. <em>gh</em>-transgenic zebrafish and their non-transgenic full siblings were evaluated for intestinal architecture and barrier function. Images of transmission electron microscopy revealed a greater frequency of AJC disruption in <em>gh</em>-transgenic fish. These ultrastructural changes were associated with increased transcription of TJ-related genes, including <em>cldn15a</em>, <em>oclna</em>, and <em>zo1a</em>, as assessed by qRT-PCR, and a higher intestinal permeability to macromolecule (RITC-dextran 10,000 MW). These findings demonstrate that chronic <em>gh</em> overexpression alters intercellular epithelial architecture and enhances intestinal paracellular permeability. This may reflect an adaptive mechanism to meet increased energy demands under anabolic conditions. Moreover, these results suggest a mechanistic link between GH signaling pathways and modulation of the intestinal barrier, with potential implications for biomedical science.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"310 ","pages":"Article 111936"},"PeriodicalIF":2.2,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145214561","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}