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

{"title":"HSP70 is upregulated after heat but not freezing stress in the freeze-tolerant cricket Gryllus veletis","authors":"Victoria E. Adams,&nbsp;Maranda L. van Oirschot,&nbsp;Jantina Toxopeus","doi":"10.1016/j.cbpa.2024.111791","DOIUrl":"10.1016/j.cbpa.2024.111791","url":null,"abstract":"<div><div>Heat shock proteins (HSPs) are well known to prevent and repair protein damage caused by various abiotic stressors, but their role in low temperature and freezing stress is not well-characterized in insects compared to other thermal challenges such as heat stress. Ice formation in and around cells is hypothesized to cause protein damage, yet many species of insects can survive freezing, suggesting HSPs may be an important mechanism in freeze tolerance. Here, we studied <em>HSP70</em> in a freeze-tolerant cricket <em>Gryllus veletis</em> to better understand the role of HSPs in this phenomenon. We measured expression of one heat-inducible <em>HSP70</em> isoform at the mRNA level (using RT-qPCR), as well as the relative abundance of total HSP70 protein (using semi-quantitative Western blotting), in five tissues from crickets exposed to a survivable heat treatment (2 h at 40 °C), a 6-week fall-like acclimation that induces freeze tolerance, and a survivable freezing treatment (1.5 h at −8 °C). While <em>HSP70</em> expression was upregulated by heat at the mRNA or protein level in all tissues studied (fat body, Malphigian tubules, midgut, femur muscle, nervous system ganglia), no tissue exhibited <em>HSP70</em> upregulation within 2–24 h following a survivable freezing stress. During fall-like acclimation to mild low temperatures, we only saw moderate upregulation of <em>HSP70</em> at the protein level in muscle, and at the RNA level in fat body and nervous tissue. Although HSP70 is important for responding to a wide range of stressors, our work suggests that this chaperone may be less critical in the preparation for, and response to, moderate freezing stress.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"300 ","pages":"Article 111791"},"PeriodicalIF":2.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142808734","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":"Kinetic comparisons of jaw opening, jaw closing and locomotor muscles","authors":"Clinton J. Moran ,&nbsp;Shannon P. Gerry","doi":"10.1016/j.cbpa.2024.111782","DOIUrl":"10.1016/j.cbpa.2024.111782","url":null,"abstract":"<div><div>Understanding contraction dynamics of skeletal muscle is critically important to appreciate performance capabilities of skeletal structures, especially for structures responsible for feeding and/or locomotion. Furthermore, it is important to understand how temperature can impact contraction dynamics in vertebrates that are regularly exposed to fluctuations in temperature. We aimed to address differences between jaw opening (sternhyoideus), jaw closing (adductor mandibulae) and locomotor (abductor superficialis) muscle contraction dynamics in a labrid fish. Additionally, we aimed to understand how temperature changes impact contraction kinetics in these muscles. To address these aims we collected cunner (<em>Tautogolabrus adspersus</em>) from Long Island Sound and removed their primary locomotor and jaw opening/closing muscles. Following dissection, the muscles were placed on a muscle ergometer that controlled length, stimulus duration and stimulation intensity. Muscles were exposed to 7, 15 and 22 °C for all experiments. We found that the swimming muscle was slower to contract and relax than both feeding muscles. Swimming muscle produced more power than feeding muscles when tested at 8 Hz and 15 °C. Jaw closing muscle produced more force than the other two muscle types when tested at22 °C. Despite these differences, muscle contraction kinetics were remarkably similar across the three muscle types and temperatures. To our knowledge this is the first study to measure <em>in vitro</em> contraction dynamics of fish jaw opening and closing muscle. This advances the understanding of the physiological capabilities of these muscles. Additionally, differences in contraction dynamics can further our understanding of the physiological limits temperature impart on whole muscle contraction.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"300 ","pages":"Article 111782"},"PeriodicalIF":2.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142711798","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":"Prolactin locally mediates follicular atresia in hyperprolactinemic vizcachas (Rodentia, Chinchillidae)","authors":"Santiago A. Cortasa ,&nbsp;Luisa A. Quiroga-Baeza ,&nbsp;Alejandro R. Schmidt ,&nbsp;Sofía Proietto ,&nbsp;Maria C. Corso ,&nbsp;Alfredo D. Vitullo ,&nbsp;Verónica B. Dorfman ,&nbsp;Julia Halperin","doi":"10.1016/j.cbpa.2024.111787","DOIUrl":"10.1016/j.cbpa.2024.111787","url":null,"abstract":"<div><div>Infertility in hyperprolactinemic females is attributed to the dysregulation of GnRH release, subsequently affecting gonadotropin levels, and ultimately leading to anovulation. However, in addition to the hypothalamus, prolactin receptor (PRLR) is expressed in ovaries as well, suggesting potential local effects of PRL in cases of hyperprolactinemia. We have developed an experimental model of sulpiride (SPD)-induced hyperprolactinemia using a wild rodent, the plains vizcacha, and studied the implications of pharmacological PRL levels on folliculogenesis and steroid production. Ovaries of SPD females showed a striking number of atretic follicles along with a reduction in the collective number of viable follicles leading to a higher atretic/viable follicle ratio compared to that of control females (CTL) (<em>P</em> &lt; 0.05). In terms of sensitivity to the hormonal environment, SPD ovaries substantially changed their potential responsiveness to pituitary PRL, as evidenced by the three-fold increase in PRLR expression alongside heightened expression of both gonadotropic receptors in comparison to CTL ovaries (<em>P</em> &lt; 0.05). Circulating estradiol (E2) values doubled post-treatment in the SPD females, which also showed higher expressions of aromatase and 17β-hydroxysteroid dehydrogenase, along with both E2 receptors, ERα and ERβ than the CTL group (<em>P</em> &lt; 0.05). Our findings strongly suggest that hyperprolactinemia-dependent dysregulation of ovarian function can be explained at least partially, by PRL direct actions facilitated by the heightened expression of PRLR in follicles and corpora lutea. Possibly these PRL actions synergize with those triggered by gonadotropic hormones ultimately leading to alteration of the steroidogenic pathway, folliculogenesis disruption and increased atresia.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"300 ","pages":"Article 111787"},"PeriodicalIF":2.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142792933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Developing under artificial light is not so bright: Oxidative stress as a physiological response to light pollution across amphibian life stages","authors":"Tamara G. Petrović ,&nbsp;Jelena P. Gavrić-Čampar ,&nbsp;Pablo Burraco ,&nbsp;Branka R. Gavrilović ,&nbsp;Svetlana G. Despotović ,&nbsp;Tijana B. Radovanović ,&nbsp;Ana Radmilović ,&nbsp;Marko Mirč ,&nbsp;Nataša Tomašević Kolarov ,&nbsp;Marko D. Prokić","doi":"10.1016/j.cbpa.2025.111819","DOIUrl":"10.1016/j.cbpa.2025.111819","url":null,"abstract":"<div><div>Light pollution has emerged as a new environmental challenge. Natural light has long been a selecting force in shaping physiological, morphological and behavioral traits across species. The introduction of artificial light at night (ALAN) disrupts the natural light-dark cycle, affecting a broad range of biological processes. In amphibians, ALAN has been suggested as a potential driver behind demographic declines in recent years. In this study, we investigated how exposure to cold LED light affects the development, body length, and oxidative status of the European tree frog (<em>Hyla arborea</em>). Individuals were exposed to ALAN from egg hatching (GS25) to two developmental endpoints: the larvae (GS38) and the juveniles. The experiment included three night-time light conditions: a natural dark control (&lt;0.3 lx), LED light intensity at 20 lx, and LED light intensity at 90 lx. Larvae reared under artificial light reached metamorphosis in a shorter period and exhibited larger body sizes. Nocturnal light also induced changes in oxidative status across life stages. Tadpoles under both 20 lx and 90 lx levels experienced greater oxidative damage of lipids. Likewise, juveniles had higher oxidative damage of proteins and elevated activities of the first-line antioxidant defense enzymes (SOD, CAT and GSH-Px) in response to both light intensities. Our results show that exposure to ALAN shapes development and body size of amphibians, which appears to be accompanied by disturbances in redox balance. Overall, we highlight that ALAN can be a factor affecting amphibian populations, and thus it should be taken into consideration in future conservation strategies.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"302 ","pages":"Article 111819"},"PeriodicalIF":2.1,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143080836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sibling similarity in telomere length in Adélie penguin chicks","authors":"Coline Marciau ,&nbsp;Sophie Bestley ,&nbsp;David Costantini ,&nbsp;Olivia Hicks ,&nbsp;Mark Hindell ,&nbsp;Akiko Kato ,&nbsp;Thierry Raclot ,&nbsp;Cécile Ribout ,&nbsp;Yan Ropert-Coudert ,&nbsp;Frederic Angelier","doi":"10.1016/j.cbpa.2025.111818","DOIUrl":"10.1016/j.cbpa.2025.111818","url":null,"abstract":"<div><div>Early life telomere length is thought to influence and predict an individual's fitness. It has been shown to vary significantly in early life compared to adulthood. Investigating the factors influencing telomere length in young individuals is therefore of particular interest, especially as the relative importance of heredity compared to post-natal conditions remains largely uncertain. Adélie penguins are eco-indicators of the Antarctic ecosystem and their population are currently undergoing variable trajectories due to climate change. Here, we conducted a correlative study to investigate how telomere length was influenced by external and internal factors in Adélie penguin chicks. We found that most of the parameters we tested, including sex, body mass, brood size and hatching order as well as parental foraging trip duration, did not significantly influence chick telomere length at 32 days. However, siblings had similar telomere length, suggesting that hereditary factors play a stronger role in determining telomere length at this stage compared to the post-natal environment. In addition, telomere length and oxidative damage did not directly correlate but did interact in a complex way mediated by chick mass. High levels of oxidative damage were associated with longer telomeres in heavy chicks, whereas they were associated with shorter telomeres in light chicks. Although this mass-dependent relationship between telomere length and oxidative damage needs to be confirmed in future studies, it could reflect two different scenarios: (1) short telomeres may mimic the cost of poor nutritional conditions and oxidative damage in light chicks; (2) long telomeres may be maintained despite high oxidative damage in heavy chicks thanks to optimal nutritional conditions.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"302 ","pages":"Article 111818"},"PeriodicalIF":2.1,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143068755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The potential for heat shock exposure during early development to alter the molecular responses to subsequent exposure to heat stress in the rainbow trout","authors":"Rob J. McFarling ,&nbsp;Mickael Teixeira Alves ,&nbsp;Anke Lange ,&nbsp;Millie Clark ,&nbsp;Harry J. Woodrow ,&nbsp;Ioanna Katsiadaki ,&nbsp;Ronny van Aerle ,&nbsp;Eduarda M. Santos","doi":"10.1016/j.cbpa.2025.111817","DOIUrl":"10.1016/j.cbpa.2025.111817","url":null,"abstract":"<div><div>Fish are ectothermic animals with temperature playing a key role in their health, growth and survival. Greater occurrence of heat waves and temperature extremes, as a result of global climate change, has the potential to impact both wild and farmed populations. Within aquaculture, production is threatened by a multitude of stressors, including adverse temperatures. The propensity for environmental temperature during early embryo development to influence later life transcriptomic responses has been observed in numerous animal species, and, if harnessed, could provide a method for inducing phenotypic changes in adult aquaculture species. We hypothesise that exposure of rainbow trout embryos to temperature stress results in alterations to transcriptional responsiveness upon re-exposure later in life. To test this hypothesis, we exposed embryos to a range of different heat shock treatments during early development and then analysed their response to thermal stress at five days post hatch (dph), in comparison to naïve fish that experienced no early development heat shock. <em>Hsp70a</em> and <em>hsp70b</em> transcription was measured (using RT-QPCR) as a biomarker for thermal stress response. Significantly greater transcriptional induction of <em>hsp70a</em> in response to post-hatch thermal stress was found in heat shocked larvae compared to naïve larvae (<em>p</em> = 0.0085). The timing, intensity and duration of the initial heat shock was not found to statistically influence the alteration of <em>hsp</em> induction when compared to that of naïve larvae. Together, these results support our hypothesis that heat shock during early development has the potential to affect responsiveness to the same stressor later in life. Future studies should focus on understanding whether this could be utilised to increase robustness of fish in aquaculture.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"302 ","pages":"Article 111817"},"PeriodicalIF":2.1,"publicationDate":"2025-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143043400","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":"Gut microbiomes are largely unchanged when exposed to their amphibian host's latitudinally variable upper thermal limit","authors":"Grace J. Vaziri ,&nbsp;Bryanna Caicedo ,&nbsp;Nicole Dahrouge ,&nbsp;William G. Ryerson ,&nbsp;Jon M. Davenport ,&nbsp;Maria Stager ,&nbsp;Korin R. Jones ,&nbsp;Carlin Frost ,&nbsp;Chad L. Seewagen ,&nbsp;Tracy A.G. Rittenhouse ,&nbsp;Daniel I. Bolnick","doi":"10.1016/j.cbpa.2025.111816","DOIUrl":"10.1016/j.cbpa.2025.111816","url":null,"abstract":"<div><div>Climate change will increase the frequency and severity of temperature extremes. Links between host thermal physiology and their gut microbiota suggest that organisms' responses to future climates may be mediated by their microbiomes, raising the question of how the thermal environment influences the microbiome itself. Vertebrate gut microbiomes influence the physiological plasticity of their hosts via effects on immunity, metabolism, and nutrient uptake. The gut microbiota of ectothermic vertebrates in particular are responsive to long-term, sub-lethal gradual increases in environmental temperature. Whether and how the gut microbiota respond to brief exposure to temperatures at the upper limit of host physiological tolerance (CT_max) is poorly understood but could have downstream effects on host fitness. We assayed the CT_max of wood frogs (<em>Lithobates sylvaticus</em>) from 15 populations across a 10° latitudinal gradient. We then characterized the gut microbiota of juveniles at two time points following exposure to CT_max. Frogs from higher latitudes had lower thermal tolerance (lower CT_max) than those from lower latitudes. Unexpectedly, exposure to upper survivable temperature had little to no detectable effect on the frogs' microbiota richness, stability, or composition. Instead, we found a strong effect of time in which frogs kept in recovery conditions for four days had less diverse, but more stable gut microbiota than those that had recovered for only one day, regardless of CT_max exposure. We conclude that while wood frogs from higher latitudes have reduced thermal tolerances than those from lower latitudes, their microbial communities are largely unaffected by brief exposure to high temperatures at the edge of their physiological limits.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"302 ","pages":"Article 111816"},"PeriodicalIF":2.1,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143043401","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":"Impacts of severity and region of gill tissue resection on regeneration in Atlantic salmon (Salmo salar)","authors":"Ensiyeh Ghanizadeh-Kazerouni ,&nbsp;Dean J. Yoo ,&nbsp;Simon R.M. Jones ,&nbsp;Colin J. Brauner","doi":"10.1016/j.cbpa.2025.111815","DOIUrl":"10.1016/j.cbpa.2025.111815","url":null,"abstract":"<div><div>In a previous study, we demonstrated successful regeneration of Atlantic salmon gill tissue following up to 50 % filament resection. The present study explored 1) the capacity of gill tissue to regenerate following more severe trauma, 2) if regeneration potential varies across regions of the arch, and 3) how tissue loss impacts the physiology of neighboring unresected filaments. Fish were divided between two resected groups and a control non-resected one. In resection group-1, fish underwent 50 % and 75 % resection in the ventral and medial-dorsal regions of the first arch, while in resection group-2, the location of resection levels was reversed. The degree of filament regeneration and physiology of unresected filaments were measured at 4, 12 and 20 weeks-post-resection (WPR). Overall, the degree of regeneration was significantly higher in 50 % resected filaments relative to 75 % resected filaments. The degree of regeneration did not differ significantly between the resected groups for either of resection levels, suggesting negligible impact of filament location on arch on regeneration. The concentration of oxidized glutathione (GSSG), total glutathione (GSH), and citrate synthase activity (CSA) in intact filaments were comparable between resected and control fish at both 4 and 20 WPR. However, GSH concentration varied among resected fish with those exhibited higher GSH in intact filaments showed lower regeneration of 50 % resected filaments at 20 WPR. Our results indicate that gill tissue loss exceeding 50 % may significantly impair regeneration and that this level of tissue loss is not associated with a compensatory response (e.g. GSSG, GSH, CSA) of neighboring gill tissue.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"302 ","pages":"Article 111815"},"PeriodicalIF":2.1,"publicationDate":"2025-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143016876","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":"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}