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

{"title":"Phylogenetic and lipid metabolic differences between migratory and Egyptian-domesticated Mallard ducks (Anas platyrhynchos)","authors":"Basma Sheta ,&nbsp;Asmaa Hassan ,&nbsp;Alaa El-Din Sallam ,&nbsp;Lotfy Habbak ,&nbsp;Ayman Hyder","doi":"10.1016/j.cbpa.2025.111814","DOIUrl":"10.1016/j.cbpa.2025.111814","url":null,"abstract":"<div><div>Although a giant Egyptian domestic non-migratory duck breed is phenotypically identical to the migratory Mallard, yet it is three times larger. The current study sought to determine the genetic and metabolic differences between this duck and Mallard, which arrives in Egypt in September for wintering and departs in March. Mitochondrial DNA control region (D-loop) was extracted, amplified, sequenced, and analyzed in both ducks. Both ducks were given a high-fat diet (HFD) for 6 weeks to assess their metabolic response to this diet. Polymorphism results indicated that the D-loop is highly variable and both populations expansion is balanced. The hierarchical analysis of molecular variants (AMOVA) and interpopulation difference parameters revealed significant genetic differentiation and minimal gene flow between migrant and resident populations. Phylogeny and Network analyses revealed that domestic ducks are a distinct group that separated from mallards. Physiologically, domestic duck blood and adipose tissue had a higher level of triglycerides and adipocyte volume than that of the depleting arriving migratory Mallard ducks, while leaving Mallard parameters were the highest, suggesting a high level of preparatory fat deposition and utilization before starting the trip. In response to HFD, the expression of FA uptake genes <em>cd36</em>, <em>fabp1</em> was upregulated similarly in livers of domestic and migratory Mallard ducks, while the expression of lipid accumulation genes <em>dgat2</em> and <em>plin2</em> was higher in domestic than in migratory Mallards. However, the highest body mass and adipocytes volume gain was observed in the arriving migratory Mallards. In pectoral muscle, the expression of <em>cd36</em> and <em>fabp3</em> was higher in domestic than in leaving ducks, while in arriving Mallards, both genes were not upregulated in response to HFD. <em>Dgat2</em> was upregulated only in domestic muscle, while lipid oxidation genes <em>cpt1, lpl</em>, and the controlling <em>ppara</em> were more upregulated in leaving Mallard. In conclusion, both ducks can be genetically and metabolically differentiated. Migratory mallards are more flexible and efficient in lipid metabolism than domestic ducks.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"302 ","pages":"Article 111814"},"PeriodicalIF":2.1,"publicationDate":"2025-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143016878","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":"Food intake and the HPT axis in the cichlid fish: The implications of the gut-brain peptide cholecystokinin","authors":"Mallikarjun Gouda,&nbsp;C.B. Ganesh","doi":"10.1016/j.cbpa.2025.111813","DOIUrl":"10.1016/j.cbpa.2025.111813","url":null,"abstract":"<div><div>This work aimed to investigate the response of cholecystokinin (CCK) to starvation and its impact on food intake and the reproductive axis of the tilapia <em>Oreochromis mossambicus</em>. The fish subjected to 21 days of starvation showed a significant decrease in CCK immunoreactivity in the hypothalamus, pituitary gland, and intestine. The administration of injections of 0.5 and 5 μg of sulfated CCK-8 (CCK-8S) over 21 days resulted in a significant, dose-dependent decrease in food consumption. Administration of a high dose of CCK-8S (5 μg) caused a substantial decrease in the number of various spermatogenic cells, the intensity of androgen receptor immunoreactivity in the testis, and the percentage area of GnRH-immunoreactive fibres in the pars distalis of the pituitary gland (PPD), concurrent with a significant decline in serum levels of luteinizing hormone (LH) and 11-ketotestosterone (11-KT). Moreover, CCK-8S treatment markedly reduced the <em>in vitro</em> testicular 11-KT level. The findings indicate for the first time that CCK influences hypothalamic GnRH release into the pituitary gland, resulting in the inhibition of LH release from the pituitary and affecting testicular spermatogenesis, androgen receptor protein expression, and steroidogenesis in teleosts. In addition, CCK may also directly affect testicular steroidogenesis.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"302 ","pages":"Article 111813"},"PeriodicalIF":2.1,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143016873","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":"Upregulation of olfactory-related neuropeptide transcripts in male Macrobrachium rosenbergii in correlation to pheromone perception from molting females","authors":"Thanapong Kruangkum ,&nbsp;Kornchanok Jaiboon ,&nbsp;Rapeepun Vanichviriyakit ,&nbsp;Prasert Sobhon ,&nbsp;Charoonroj Chotwiwatthanakun","doi":"10.1016/j.cbpa.2025.111812","DOIUrl":"10.1016/j.cbpa.2025.111812","url":null,"abstract":"<div><div>Our previous studies revealed a mating attractant or possibly a pheromone released from molting reproductive mature female prawns, <em>Macrobrachium rosenbergii</em>, stimulates the expression of insulin-like androgenic gland hormones in a co-culture system. The released attractant is perceived by olfactory receptors with setae located on the short lateral antennules (slAn), which connect to the olfactory neuropil in the central nervous system (CNS) of male prawns. This neural signaling propagating through the CNS is mediated by at least four neuropeptides, namely neuropeptide F (NPF), short NPF (sNPF), tachykinin (TK), and allatostatin-A (ATS-A) whose transcripts have been detected in the present study. These deduced sequences, along with their conserved domains, serve as signatures of the identified neuropeptides, which were then compared with those found in other crustaceans and insects, whose nucleotide sequences were obtained from the nucleotide database. RT-PCR identified the expressions of the transcripts encoding these neuropeptides in the CNS. <em>In situ</em> hybridization specifically localized these transcripts in olfactory-associated neurons of cluster 9/11 of the deutocerebrum. Quantitative real-time PCR was used to quantify the expressions of the transcripts in response to the female attractants under different co-culture conditions: males with molting females (G1), males with intermolt females (G2), and slAn ablated males with molting females (G3). The transcripts were significantly increased on days 4–8 in the brain (Br) of males in G1 but not in G2 and G3. This suggests that expressions of the transcripts encoding the neuropeptides are associated with the perception of female mating pheromones through the slAn. This study is the first to show that female mating chemicals regulate the expressions and abundance of the olfactory neuropeptides, thus providing valuable insights for manipulation of mating of this species in aquaculture production.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"302 ","pages":"Article 111812"},"PeriodicalIF":2.1,"publicationDate":"2025-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142980806","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}

{"title":"Respiratory and hematological physiology of day 15 chicken embryos (Gallus gallus domesticus) during water submergence and air recovery: Implications for bird embryos experiencing nest inundation","authors":"Benjamin Dubansky ,&nbsp;Maria Rojas Antich ,&nbsp;Hiroshi Tazawa ,&nbsp;Warren Burggren","doi":"10.1016/j.cbpa.2024.111797","DOIUrl":"10.1016/j.cbpa.2024.111797","url":null,"abstract":"<div><div>Bird nests of coastal or inland breeding birds can temporarily flood during high tides or storms. However, respiratory physiological disruption of such water submersion and implications for post-submergence survival are poorly understood. We hypothesized that respiratory physiological disturbances caused by submersion would be rapidly corrected following return to normal gas exchange across the eggshell, thus explaining survival of nest inundation in the field. We further hypothesized that the chicken embryo prior to hatching will develop the ability to recover from acid-base disturbance. We exposed day 15 embryonated chicken eggs (a well-studied point 3/4 through development) to half- or full submersion in water (producing moderate and severe hypoxia, respectively) or in mineral oil (anoxia) for periods of 2–24 h to create varying degrees of submersion-related respiratory and acid-base disturbances. Egg submergence was followed by up to six hours in air to determine the extent and rate of physiological recovery. Arterialized blood PO₂ and [lactate], acid-base and hematology were measured at frequent intervals (5 min to 2 h depending on tested variable) both during submersion and air recovery. Submersion in mineral oil – eliminating all gas exchange - proved lethal at two hours. Yet, calculated embryonic oxygen stores suggest submerged embryos should be able to maintain pre-submergence oxygen consumption for only ∼15 mins, suggesting a possibly adaptive immediate decline in metabolism upon submergence. Half- or full submergence in water created blood acid-base disturbances within as little as 5 min, with partial recovery towards the end of 24 h of submergence. Six hours of subsequent air recovery fully restored acid-base homeostasis. Hematological changes that appeared within 5 min of submersion - primarily red blood cell swelling - were eliminated within 1 h following return to air. Importantly, these data indicate a surprising resilience of the chicken embryo to temporary elimination of normal gas exchange which, if evident in other species, provides underlying mechanisms for surviving nest inundation.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"302 ","pages":"Article 111797"},"PeriodicalIF":2.1,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142967461","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":"Fish models to explore epigenetic determinants of hypoxia-tolerance","authors":"William Johnston,&nbsp;Sally Adil,&nbsp;Catherine Cao,&nbsp;Niepukolie Nipu,&nbsp;Jan A. Mennigen","doi":"10.1016/j.cbpa.2025.111811","DOIUrl":"10.1016/j.cbpa.2025.111811","url":null,"abstract":"<div><div>The occurrence of environmental hypoxia in freshwater and marine aquatic systems has increased over the last century and is predicted to further increase with climate change. As members of the largest extant vertebrate group, freshwater fishes, and to a much lesser extent marine fishes, are vulnerable to increased occurrence of hypoxia. This is important as fishes render important ecosystem services and have important cultural and economic roles. Evolutionarily successful, fishes have adapted to diverse aquatic freshwater and marine habitats with different oxygen conditions. While some fishes exhibit genetic adaptions to tolerate hypoxia and even anoxia, others are limited to oxygen-rich habitats. Recent advances in molecular epigenetics have shown that some epigenetic machinery, especially histone- and DNA demethylases, is directly dependent on oxygen and modulates important transcription-regulating epigenetic marks in the process. At the post-transcriptional level, hypoxia has been shown to affect non-coding microRNA abundance. Together, this evidence adds a new molecular epigenetic basis to study hypoxia tolerance in fishes. Here, we review the documented and predicted changes in environmental hypoxia in aquatic systems and discuss the diversity and comparative physiology of hypoxia tolerance in fishes, including molecular and physiological adaptations. We then discuss how recent mechanistic advances in environmental epigenetics can inform future work probing the role of oxygen-dependent epigenetic marks in shaping organismal hypoxia-tolerance in fishes with a focus on within- and between-species variation, acclimation, inter- and multigenerational plasticity, and multiple climate-change stressors. We conclude by describing the translational potential of this approach for conservation physiology, ecotoxicology, and aquaculture.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"302 ","pages":"Article 111811"},"PeriodicalIF":2.1,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142959272","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}

{"title":"Salinity stress impairs disease resistance in white shrimp, Penaeus vannamei through AMPK pathway, ameliorated by dietary glucose-mediated energy homeostasis","authors":"Ann-Chang Cheng ,&nbsp;Chien-Ju Lin ,&nbsp;Sz-Tsan Wang ,&nbsp;Chun-Hung Liu","doi":"10.1016/j.cbpa.2024.111799","DOIUrl":"10.1016/j.cbpa.2024.111799","url":null,"abstract":"<div><div>This study presents a comprehensive examination of the physiological adaptations of white shrimp (<em>Penaeus vannamei</em>) to low-salinity conditions and evaluates the effects of supplementing dietary glucose on disease resistance. Compared to the control group, shrimp cultured at a salinity of 4 psu exhibit significantly elevated expression levels of adenosine 5′-monophosphate-activated protein kinase (AMPK) in the hepatopancreas, which leads to increased energy expenditure and a corresponding reduction in resistance to infection by <em>Vibrio alginolyticus</em>. The suppression of AMPK via dsAMPK treatment markedly enhances disease resistance. Moreover, shrimp raised in low salinity conditions exhibit downregulation of mTOR-associated molecules, including Lipin-1 and hypoxia-inducible factor 1-α (HIF-1α), both of which are essential for immune regulation. Metabolic assessments revealed reduced ATP levels and disrupted ATP/AMP and ATP/ADP ratios, indicating energy imbalance under low salinity stress. Notably, supplementing the diet with 1 % glucose significantly increased glycogen reserves and ATP content, stabilized hemolymph glucose levels, and upregulated glycolysis-related genes, thereby optimizing energy metabolism and enhancing resilience to stress. This study underscores that AMPK activation in response to low salinity conditions leads to increased energy expenditure, which in turn lowers disease resistance. Furthermore, it underscores the critical role of strategic dietary management in maintaining energy homeostasis and improving disease resistance in white shrimp under stressful environmental conditions associated with climate change, offering valuable insights for aquaculture nutrition strategies.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"302 ","pages":"Article 111799"},"PeriodicalIF":2.1,"publicationDate":"2025-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142959276","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":"Evolutionary insights and expression patterns of sex-related gene families in the zig-zag eel Mastacembelus armatus","authors":"Yuanyuan Wang ,&nbsp;Fangyu Cui ,&nbsp;Yexin Yang ,&nbsp;Haiyan Liang ,&nbsp;Yuli Wu ,&nbsp;Aiguo Zhou ,&nbsp;Yi Liu ,&nbsp;Zhiyong Jiang ,&nbsp;Jintao Peng ,&nbsp;Xidong Mu","doi":"10.1016/j.cbpa.2025.111804","DOIUrl":"10.1016/j.cbpa.2025.111804","url":null,"abstract":"<div><div>The zig-zag eel exhibits both sexual dimorphism and sex reversal, making it crucial to understand the mechanisms of sex determination and differentiation. Additionally, the wild populations of the zig-zag eel are significantly declining, emphasizing the need for urgent conservation efforts. In this study, we identified 7 Dmrt, 62 HMG-box, and 73 TGF-β family members in the zig-zag eel genome. Evolutionary analysis revealed that the HMG-box and TGF-β families in the zig-zag eel are primarily characterized by purifying selection. Furthermore, we identified 52 differentially expressed genes between males and females, with more male-biased genes than female-biased genes within these three gene families. <em>ZzDmrt2a</em> was highly expressed in the ovary, while <em>ZzDmrt2b</em> was highly expressed in the testis. Interestingly, <em>Zzgdf9</em>, located on the Y chromosome, was significantly expressed in the ovary. Our results highlight the complexity of sex differentiation mechanisms and underscores the importance of further research to elucidate the specific functions and regulatory networks of these sex-biased genes. Such insights could inform breeding strategies in aquaculture, contributing to the conservation and management of the zig-zag eel.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"301 ","pages":"Article 111804"},"PeriodicalIF":2.1,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142933329","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":"Saccular potentials of the male round goby, Neogobius melanostomus, a hearing non-specialist","authors":"Brooke J. Vetter","doi":"10.1016/j.cbpa.2024.111802","DOIUrl":"10.1016/j.cbpa.2024.111802","url":null,"abstract":"<div><div>The round goby (<em>Neogobius melanostomus</em>) is a benthic fish species native to Central Eurasia but has colonized much of the waterways in the Laurentian Great Lakes in North America. While they are known to produce acoustic signals that aid in conspecific agonistic and reproductive interactions, the species does not possess a swim bladder and thus does not have any hearing specializations that would allow for sound pressure detection. Here, the auditory evoked potentials from saccular hair cells were characterized to determine the frequency response and auditory sensitivity of the saccule. Saccular potentials were recorded from the medial region of the saccular maculae during playback of single frequency acoustic stimuli (105–605 Hz). Auditory tuning curves based on both sound pressure (dB re: 1 μPa.) and particle acceleration (dB re: 1 ms⁻²) suggest that the saccule is most sensitive to 105 and 125 Hz and that the highest thresholds occurred at frequencies ≥205 Hz.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"302 ","pages":"Article 111802"},"PeriodicalIF":2.1,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142933340","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":"The use of physicochemical properties to assess changes in the cuticle structure of crustaceans: Case of the prawn Palaemon serratus and its moult cycle","authors":"Marc Rollin ,&nbsp;Benoit Xuereb ,&nbsp;Romain Coulaud ,&nbsp;Vincent Loisel ,&nbsp;Agnès Poret ,&nbsp;Aurélie Duflot ,&nbsp;Frank Le Foll ,&nbsp;Céline Picard ,&nbsp;Nicolas Hucher","doi":"10.1016/j.cbpa.2024.111801","DOIUrl":"10.1016/j.cbpa.2024.111801","url":null,"abstract":"<div><div>The crustacean cuticle is a composite material acting as a shell, but also linked with other physiological functions as respiration, locomotion or reproduction. The present study aimed to characterize for the first time the cuticle properties of the marine prawn <em>Palaemon serratus</em> using thermal (TGA) and chemical (FTIR, ICP-AES) techniques. The use of native lyophilized cutiles also enabled to estimate the complexity of the cuticle structure of <em>P. serratus</em>. Hence, the prawn cuticle was found to be composed of bound water at 14 %, Light macromolecules at 27 %, heavy macromolecules at 17 % and inorganic elements at 42 %. This composition appeared to be similar to that of other swimming crustaceans, suggesting an adaptation of the cuticle structure in line with the ecology of the species. Then, thermal and chemical techniques were applied to characterize the structure changes of the cuticle induced by <em>i)</em> the moult cycle and <em>ii)</em> formic acid treatment. The moult cycle influence assessment revealed that the physicochemical properties were mainly modulated during postmoult, reflecting both the cuticle mineralization and tanning. Then, formic acid treatment led to cuticle alterations, related to the dissolution of amorphous minerals, which were detected by TGA, FTIR and ICP-AES. With these results, the assessment of cuticle properties using a combination of thermal and chemical techniques appeared to be interesting to monitor changes in cuticle structure in a dynamical context.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"302 ","pages":"Article 111801"},"PeriodicalIF":2.1,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142933341","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}

{"title":"Prior heatwave exposure improves hypoxia tolerance in a typical freshwater fish species","authors":"Weihui Huang ,&nbsp;Nanyan Weng ,&nbsp;Jingtian Zhang ,&nbsp;Hanxiao Zhang ,&nbsp;Yunxin Duan ,&nbsp;Xinyi Gen ,&nbsp;Shouliang Huo","doi":"10.1016/j.cbpa.2025.111803","DOIUrl":"10.1016/j.cbpa.2025.111803","url":null,"abstract":"<div><div>The prevalence of heatwave and hypoxia events and their devastating impacts on aquatic ecosystems and fishery resources reinforces the priority of research to address the resilience and adaption mechanisms to these two stressors in important fish species. However, our understanding of the development of cross-tolerance of these two stressors in fish still limited. Here, we investigated the impacts of prior heatwave exposure on hypoxia tolerance and the underlying mechanisms in silver carp (<em>Hypophthalmichthys molitrix</em>), a species of considerable ecological and commercial importance. Our results revealed that prior heatwave exposure significantly reduced the dissolved oxygen levels required to induce aquatic surface respiration (ASR₅₀) and loss of equilibrium (LOE₅₀) in juvenile silver carp, indicating the development of cross-tolerance to hypoxia. Physiologically, prior exposure to heatwaves significantly induced gill remodeling by triggering extensive apoptosis. These pre-existing physiological alterations and similar morphological alterations induced by subsequent hypoxia resulted in cumulative effects, leading to extensive gill remodeling under hypoxic conditions and thereby improving hypoxia tolerance. Molecularly, heatwave exposure modulated the expression of critical genes associated with hypoxia adaptation with tissue-specific responses. In the gill, heatwave exposure activated the hypoxia-induced factor (HIF) signaling pathway, increasing oxygen transport (<em>VEGF-A, HB-β</em>) and antioxidant gene expression (<em>GPx, SOD2</em>), facilitating rapid adaptation to hypoxia. In the liver, this exposure resulted in accelerated and enhanced gene expression of <em>HIF-1α</em>, anaerobic metabolism (<em>GLUT-1</em>, <em>LDH-A</em>), and heat shock protein (<em>HSP70</em>) under hypoxic conditions, contributing to improved adaptation. These results highlighted that prior exposure to heatwaves provided cross-tolerance to silver carp, bolstering their resilience to hypoxia through physiological gill remodeling and tissue-specific transcriptional adjustments. Our findings shed light on the intricate interactions of silver carp's thermal and hypoxic stress resilience, offering valuable perspectives for predicting and alleviating climate change impacts on aquatic life.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"302 ","pages":"Article 111803"},"PeriodicalIF":2.1,"publicationDate":"2025-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142933330","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}