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

{"title":"Growth rate is associated with reduced oxidative stress and this effect is modulated by the degree of social dominance in males of an African cichlid fish","authors":"Peter D. Dijkstra","doi":"10.1016/j.cbpa.2025.111892","DOIUrl":"10.1016/j.cbpa.2025.111892","url":null,"abstract":"<div><div>Attaining large body size has several selective benefits, however, increased growth rate has potential costs that can constrain investment in other life history traits, such as reproductive output and territorial defense. Oxidative stress can both constrain and result from growth, potentially mediating life history trade-offs between growth rate and other life history traits. Studies on the oxidative cost of growth have provided mixed evidence, in part because components of oxidative balance, including oxidative damage and antioxidant function, is influenced by investment in other activities in a tissue-specific manner. Here, I examined how among-individual variation in growth rate is linked to oxidative stress, and how this relationship is influenced by markers of social dominance (aggressiveness and relative gonad size) in males of the cichlid fish <em>Astatotilapa burtoni</em>. To this end, 7 markers of oxidative damage and antioxidant function in various tissue types (total of 14 measurements) were assessed in dominant and subordinate males. I found that dominant males grew faster than subordinate males. However, increased growth was linked to reduced oxidative stress. This effect was independent of social status but modulated by the degree of social dominance. Overall, the results are consistent with oxidative stress mediating the link between growth and other life history traits. However, my findings challenge the idea that increased growth rate results in elevated oxidative stress, perhaps due to effective protective mechanisms that can neutralize the oxidative challenge of growth.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"307 ","pages":"Article 111892"},"PeriodicalIF":2.1,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144259425","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":"Short-term exposure to dim light at night affects reproduction and metabolism-linked processes in adult male tree sparrows (Passer montanus)","authors":"Subu Yatung,&nbsp;Amit Kumar Trivedi","doi":"10.1016/j.cbpa.2025.111902","DOIUrl":"10.1016/j.cbpa.2025.111902","url":null,"abstract":"<div><div>Anthropogenic factors, particularly urbanization, have immense implications for the natural light-dark cycle of the species. The present study deliberates on the effects of dim light at night on the transcript expression of reproductive, steroidogenic, and metabolic gene markers in adult male tree sparrows (<em>Passer montanus</em>). Adult male birds were procured locally and were divided into two groups (<em>n</em> = 6 birds/group). Both groups were exposed to 12 h of light and 12 h of darkness, but group two (dLAN group) with a constant dim light (10 lx) during the dark hours. The experiment was run for 2 weeks. After that, birds were sampled, and the hypothalamus, liver, and gonads were harvested and used for gene expression analysis. Blood plasma was used for hormonal and biochemical assays. The findings suggest that 2 weeks of exposure did not significantly change the body mass, cholesterol, glucose, and testosterone assay. However, an increase in testicular volume was observed in dLAN-treated birds. Furthermore, elevation in hypothalamic transcripts (<em>Tshβ</em>, <em>Dio2</em>, <em>GnRH</em>, and <em>Eya3)</em> involved in the seasonal reproduction, along with an increase in steroidogenic transcripts (<em>StAr</em>, <em>Scp2</em>, <em>Srd5a1</em>, <em>Hsd11b2</em>, and <em>Er</em>) in the testis was observed; besides, liver metabolic transcript levels (<em>Acaca</em>, <em>Fasn</em>, <em>Hmcg</em>, <em>Idh2</em>, <em>Sdhaf4</em>, <em>Sdhaf2</em>, <em>Sdhc</em>, <em>Fh</em>, <em>Mdh</em>, <em>Foxo1</em>, and <em>Vip</em>) were also elevated in the dLAN-treated group compared to the control group. Overall, the study shows that even a short-term exposure to the lower intensity of dim light at night of 2 weeks of duration can stimulate the hypothalamic gonadal axis and liver metabolism in tree sparrows. These results could play a role in understanding the effect of light at night on the physiology of diurnal avian species.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"307 ","pages":"Article 111902"},"PeriodicalIF":2.1,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144549430","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":"Dealing with the heat: Assessing heat stress in an Arctic seabird using 3D-printed thermal models","authors":"Fred Tremblay ,&nbsp;Emily S. Choy ,&nbsp;David A. Fifield ,&nbsp;Glenn J. Tattersall ,&nbsp;François Vézina ,&nbsp;Ryan O'Connor ,&nbsp;Oliver P. Love ,&nbsp;Grant H. Gilchrist ,&nbsp;Kyle H. Elliott","doi":"10.1016/j.cbpa.2025.111880","DOIUrl":"10.1016/j.cbpa.2025.111880","url":null,"abstract":"<div><div>The Arctic is warming at four times the global average rate and most studies have focused on the indirect (e.g., changes in food web) rather than the direct effects of climate change. However, as Arctic animals often have low capacity to dissipate heat, the direct effect of warming could impact them significantly (heat stress). To study heat stress, biophysical models have been used in many species to estimate operative temperature (Te, integrated temperature of the thermal environment experienced by an individual). Here, we developed biophysical models of an Arctic seabird, the thick-billed murre (<em>Uria lomvia</em>). We demonstrated that 3D-printed painted models perform similarly to the more traditionally used feather-covered models. We deployed our models on Coats Island, Nunavut, Canada to study heat stress, which occurs in murres when operative temperature is above 21.2 °C (the temperature at which evaporative water loss (EWL) rates increase to maintain a constant body temperatures). Murre operative temperatures ranged from 5.5 °C to 46.5 °C despite ambient temperatures never exceeding 24.7 °C (range: 3.4–24.7 °C), and murres experienced heat stress on 61 % of the days during the breeding season (range: 24–85 %). Using known equations of EWL as a function of temperature, we estimated that murres lost 3.79 % to 4.61 % of their body mass in water daily. Our study confirms the physiological challenges faced by Arctic seabirds during the breeding season, while also demonstrating the value of biophysical models as non-invasive tools to study the effects of heat stress on seabirds.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"306 ","pages":"Article 111880"},"PeriodicalIF":2.1,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144113110","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":"Participation of membrane-initiated cortisol effects on the rapid acclimation of rainbow trout (Oncorhynchus mykiss) to increased salinity","authors":"Jorge Eduardo Aedo ,&nbsp;Daniela Aravena-Canales ,&nbsp;Juan Antonio Valdés ,&nbsp;Alfredo Molina","doi":"10.1016/j.cbpa.2025.111866","DOIUrl":"10.1016/j.cbpa.2025.111866","url":null,"abstract":"<div><div>Cortisol, a fundamental slow-acting hormone in teleosts, plays a crucial role in acclimating to changes in saline environments. Cortisol effects are associated with its interaction with intracellular glucocorticoid (GR) and mineralocorticoid (MR) receptors, which subsequently regulate gene expression through the cortisol-receptor complex. This mechanism is known as a genomic cortisol signaling and has been studied extensively. However, recent studies have begun to explore a membrane-initiated cortisol pathway that is initiated on the cellular surface, revealing its critical role in the initial metabolic adjustments during the physiological stress response. Nevertheless, the role of this novel membrane-mediated cortisol action during acclimatization to saline environments remain to be elucidated. To investigate this, an <em>in vivo</em> assay was performed in which juvenile rainbow trout were maintained in freshwater (FW) (0.1 ppt), intraperitoneally injected with vehicle, cortisol or cortisol-BSA (three hours of treatment), and transferred to saline water (15 ppt) for one additional hour. Samples of blood and gills were obtained from each fish in order to measure the plasma cortisol, glucose and chloride concentrations, as well as the expression levels of the <em>gr1</em>, <em>gr2</em>, <em>mr</em>, and key osmoregulatory genes. Membrane-initiated cortisol action increased plasma glucose and chloride levels in fish after one hour of saline transfer in comparison with the vehicle group. Furthermore, cortisol exerts a novel regulatory influence on the expression of <em>gr2,</em> as well as tight junction proteins <em>claudin10e</em> and <em>cldn30</em> in the gills. In contrast, other osmoregulation-related genes, such as <em>cftr and nkcc1</em>, are exclusively mediated by genomic cortisol signaling. These results suggest that membrane-initiated cortisol action plays a significant role in the rapid acclimation of fish to changes in salinity environments.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"306 ","pages":"Article 111866"},"PeriodicalIF":2.1,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143887694","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":"Response of Atlantic salmon to long-term sustained aerobic training at suboptimum elevated temperature: Cardiac anatomy, aerobic performance, and growth implications","authors":"Marco Foddai ,&nbsp;Chris G. Carter ,&nbsp;Andrew T. Wood ,&nbsp;Kelli C. Anderson ,&nbsp;Jayson M. Semmens","doi":"10.1016/j.cbpa.2025.111874","DOIUrl":"10.1016/j.cbpa.2025.111874","url":null,"abstract":"<div><div>Sustained aerobic training is suggested to enhance cardiac performance and growth in farmed salmonids, but its effects under suboptimum elevated temperatures remain unclear. This study examined whether continuous training at different temperatures could improve growth and whether it influenced cardiac performance at a suboptimum elevated temperature in a context relevant to offshore aquaculture. Atlantic salmon were reared for 90 days at 15 °C (control temperature) and 20 °C (suboptimum elevated temperature), with either continuous aerobic swimming (trained: 0.45 m.s⁻¹) or standard conditions (untrained: 0.18 m.s⁻¹). Growth and feed intake were assessed at both temperatures, while cardiac and metabolic parameters were measured only at 20 °C.</div><div>At 15 °C, trained fish exhibited increased feed intake, but this did not translate into improved growth. At 20 °C, neither feed intake nor growth improved with training. Swim-tunnel respirometry at 20 °C revealed no significant differences in aerobic performance between trained and untrained fish, although trained fish exhibited lower interindividual variability in metabolic and swimming parameters. While training increased relative ventricular mass (RVM), indicating potential cardiac remodelling, this did not result in improved metabolic performance.</div><div>These findings underscore the complexity of physiological responses to exercise and temperature in salmon aquaculture. While continuous aerobic training induced minor cardiac adaptations, its impact on growth and performance was limited, particularly at suboptimum elevated temperatures. This research provides valuable insights into how Atlantic salmon may respond to offshore farming environments, with specific relevance to Tasmania's aquaculture industry.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"306 ","pages":"Article 111874"},"PeriodicalIF":2.1,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143906312","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":"Polyamine dynamics and transcriptomic changes in honey bees (Apis mellifera, L.) during aging","authors":"Jelena Purać ,&nbsp;Elvira Vukašinović ,&nbsp;Marko Kebert ,&nbsp;Tatjana Čelić ,&nbsp;Srđana Đorđievski ,&nbsp;Jelena Spremo ,&nbsp;Ivan Pihler ,&nbsp;Danijela Kojić","doi":"10.1016/j.cbpa.2025.111870","DOIUrl":"10.1016/j.cbpa.2025.111870","url":null,"abstract":"<div><div>Honey bees (<em>Apis mellifera,</em> L.) play an important role in ecosystems due to their pollination, which directly impacts biodiversity and agricultural production. Understanding the biological mechanisms that determine bee aging is important for conserving bee populations and the ecosystems they serve. This study explored the dynamics of polyamine level changes and transcriptomic alterations during the aging of summer and winter worker bees. The present study's results indicate that the polyamine content in summer bees decreased overall with age, while winter bees exhibited a biphasic pattern, with an initial decrease followed by an increase in older individuals. These differences likely reflect distinct physiological needs during summer (work-intensive) and winter (survival-focused) periods. Transcriptomic analyses identified age-related changes, with key driver gene analysis highlighting critical genes associated with cuticle formation, venom activity, and polyamine metabolism, indicating structural and metabolic adaptations with age. KEGG pathway analysis identified enrichments in pathways related to peroxisome function, lipid metabolism, glycan degradation, lysosomal activity, and others underscoring shifts in cellular maintenance and energy regulation. This study underscores the complexity of polyamine dynamics and molecular adaptations in honey bee aging and provides a foundation for conserving bee populations and better understanding longevity across species.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"306 ","pages":"Article 111870"},"PeriodicalIF":2.1,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143887692","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":"Acidification affects the early development of Colombian endemic fish Prochilodus magdalenae","authors":"Villamizar Natalia ,&nbsp;Guardiola Jose Luis ,&nbsp;Cruz-Botto Sara ,&nbsp;Rodríguez Hector Alejandro ,&nbsp;Reyes-Bermúdez Alejandro ,&nbsp;Noisette Fanny","doi":"10.1016/j.cbpa.2025.111875","DOIUrl":"10.1016/j.cbpa.2025.111875","url":null,"abstract":"<div><div>There is a significant knowledge gap regarding the acidification of freshwater ecosystems and its effects on biological systems. The bocachico (<em>Prochilodus magdalenae</em>), an endemic and migratory species vital to Colombia's inland fisheries, is currently classified as vulnerable. This study evaluated the impact of different pH levels (6.2, 7.2, and 7.6), previously recorded in the species' natural habitat, on its early development. Using an automated IKS Aquastar system, embryo incubation and larval maintenance were monitored from 0 to 5 days post-fertilization, assessing development, hatching, and survival at both organismal and transcriptional levels. Embryos exposed to pH 6.2 showed delayed development within 4 h post-fertilization, the lowest hatching rate (68.33 ± 3.13 %), and survival (23.88 ± 4.53 %), along with the highest incidence of malformations (37.80 ± 4.4 %). The pH 7.6 group also showed adverse effects, but to a lesser extent. Transcriptome analysis revealed a distinct molecular response in the pH 6.2 group, identifying 1214 differentially expressed genes related to early development, ossification, organ formation, sensory systems, and cellular processes. The findings indicate that pH fluctuations previously observed in the species' natural environment significantly affect <em>P. magdalenae</em> during early life stages, which raises serious concerns about the long-term viability of this endemic species and the sustainability of the artisanal fisheries that depend on it.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"306 ","pages":"Article 111875"},"PeriodicalIF":2.1,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143935966","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":"Transcriptional analysis reveals antioxidant, ion transport, and glycolysis mechanisms in Litopenaeus vannamei gills involved in the response to high alkali stress","authors":"Yiming Li ,&nbsp;Yucong Ye ,&nbsp;Xiaoyi Zhu ,&nbsp;Yuxing Wei ,&nbsp;Yan Li ,&nbsp;Zhen Sun ,&nbsp;Kai Zhou ,&nbsp;Pengcheng Gao ,&nbsp;Zongli Yao ,&nbsp;Qifang Lai","doi":"10.1016/j.cbpa.2025.111868","DOIUrl":"10.1016/j.cbpa.2025.111868","url":null,"abstract":"<div><div>Saline-alkali aquacultural systems have an important role in improving the economic output of the aquacultural industry. However, the survival rate of shrimp in intensive aquacultural systems is affected by alkalinity fluctuations. This study explored the ion transport and molecular responses of the whiteleg shrimp <em>Litopenaeus vannamei</em> to short-term high alkaline stress (96 h). The results showed that survival rate decreased significantly with time, hemolymph osmotic pressure and oxygen consumption dropped sharply after peaking at 48 h, and ammonia excretion followed a non-monotonic pattern, with an initial decline followed by a subsequent increase. Analysis of key physiological indicators revealed that urea nitrogen continued to accumulate, antioxidant (SOD and CAT) and glycolytic (PFK and LDH) enzymes were significantly activated, but ion regulatory enzymes (Na⁺/K⁺-ATPase) were severely suppressed. Gill histopathology showed typical injuries (such as gill filament shrinkage, vacuolation, and hemocytopenia). Furthermore, transcriptome analysis confirmed that high alkali stress activated insulin signaling pathway and glycolysis-related genes (e.g., upregulating <em>PFK</em> and <em>GLUT</em> expression). These results indicate that the high alkalinity causes an ion imbalance, changes the ammonia transport process, and activates the glycolysis pathway. These conclusions provide a theoretical basis for the subsequent development for the saline-alkaline aquacultural of <em>Litopenaeus vannamei</em>.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"306 ","pages":"Article 111868"},"PeriodicalIF":2.1,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143860209","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":"Metabolic responses to thermal ramping in two endemic eurybathic amphipods of the genus Ommatogammarus from ancient Lake Baikal","authors":"Yulia Shirokova ,&nbsp;Ekaterina Telnes (Madyarova) ,&nbsp;Andrey Mutin ,&nbsp;Yaroslav Rzhechitskiy ,&nbsp;Zhanna Shatilina ,&nbsp;Inna Sokolova ,&nbsp;Maxim Timofeyev","doi":"10.1016/j.cbpa.2025.111881","DOIUrl":"10.1016/j.cbpa.2025.111881","url":null,"abstract":"<div><div>Lake Baikal harbors freshwater profundal amphipods, including the eurybathic species <em>Ommatogammarus flavus</em> and <em>O. albinus</em>. <em>O. flavus</em> occupies shallower habitats, including the littoral zone, which is subject to greater temperature variability. Consequently, <em>O. flavus</em> may demonstrate a higher degree of tolerance to temperature fluctuations in comparison with <em>O. albinus</em>. We compared the metabolic responses of these two amphipod species to thermal ramping. Specimens were collected from a range of depths and acclimated to a temperature of 4 °C. They were then subjected to controlled temperature up- and downshifts to assess the parameters of tissue energy status, antioxidant enzyme activity, and survival. <em>O. flavus</em> showed a higher degree of tolerance to warming than the deeper-dwelling <em>O. albinus</em>, while both species were resilient to temperature decreases. The depth of sampling had a minor effect on glycogen levels in <em>O. flavus</em> as well as catalase and glutathione S-transferase activity in <em>O. albinus</em> but had no effect on survival during experimental warming. Glucose level was shown to be the most sensitive biochemical marker to temperature variations, indicating that it could be used as a stress indicator for Baikal deep-water amphipods. This finding might provide insight into their adaptability to ambient temperature fluctuations.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"306 ","pages":"Article 111881"},"PeriodicalIF":2.1,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144087090","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":"Changes in thermal preference, respiratory and metabolic patterns in Tropidurus torquatus: Population responses from two distinct Brazilian biomes","authors":"Sofia L. B. da S. Matos ,&nbsp;Lays de Souza Porto ,&nbsp;Melissa Bars-Closel ,&nbsp;Fábio Cury de Barros ,&nbsp;Tiana Kohlsdorf ,&nbsp;Kenia C. Bícego ,&nbsp;Luciane H. Gargaglioni","doi":"10.1016/j.cbpa.2025.111871","DOIUrl":"10.1016/j.cbpa.2025.111871","url":null,"abstract":"<div><div>Variations in structural and climatic conditions of habitats, particularly in environmental temperatures, emerge as a pivotal determinant exerting broad influence on physiological processes, such as modifications in ventilation and metabolism within certain species. We investigated the thermal preference, ventilatory, and metabolic responses to acclimation in two Brazilian populations of the lizard <em>Tropidurus torquatus</em> — one population from the Pampa biome and the other from the restinga (sandbank) ecosystems in the Atlantic Forest biome. We divided lizards into three distinct acclimation temperatures (20 °C – ‘cold’, 25 °C – ‘warm’, and 30 °C – ‘hot’ regimes) and, after three weeks, recorded their preferred temperatures. Subsequently, we measured ventilation and metabolism in the same individuals at 20 °C, 25 °C, and 30 °C. Both populations exhibited similar responses to acclimation in thermal variables. However, in the extreme acclimation regimes, the Pampa population selects colder temperatures more frequently than the Restinga population. We did not detect any effect of acclimation or population on ventilation. In contrast, we identified changes in respiratory frequency likely related to changes in acclimation temperature regimes for both populations. In terms of metabolism, we recorded lower oxygen consumption in the Pampa population at warm and hot acclimation regimes. Our findings suggest that physiological responses to acclimation in <em>T. torquatus</em> may be intricately molded by the specific environmental contexts in which populations are situated. Animals originating from the southern population exhibit increased thermal responses – like the reduction of O₂ consumption when faced with 30 °C experimental temperature – potentially attributed to their exposure to more variable temperature regimes in their native habitat.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"306 ","pages":"Article 111871"},"PeriodicalIF":2.1,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143899916","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}