Vitamins are essential micronutrients involved in various biochemical processes, such as serving as cofactors, antioxidants, and regulators of calcium metabolism. In vertebrates, vitamins D, K, and C are particularly known for supporting bone health and mineralization. However, the role of vitamins in biomineralization processes in marine invertebrates, such as octocorals (cnidarians) that produce internal skeletal structures called sclerites, remains largely unexplored.
This study uses an in vivo injection method in the octocoral Sarcophyton sp. to assess the effects of various vitamins on sclerite formation over 21 days. Calcification was monitored using calcein, a fluorescent marker, and analyzed by confocal microscopy combined with particle analysis. Our results indicate that vitamin D promotes sclerite formation, whereas vitamin C appears to inhibit this process, suggesting distinct roles for specific vitamins in octocoral biomineralization.
These findings provide experimental evidence of vitamin-mediated regulation of biomineralization in octocorals. By identifying conserved pathways in cnidarian skeletal formation, this study lays the groundwork for future research in coral physiology, and more broadly on comparative endocrinology, and may contribute to broader insights into coral resilience.
{"title":"A window into vitamin effects on biomineralization in octocorals","authors":"Clémence Forin , Denis Allemand , Sylvie Tambutté , Philippe Ganot","doi":"10.1016/j.ygcen.2025.114854","DOIUrl":"10.1016/j.ygcen.2025.114854","url":null,"abstract":"<div><div>Vitamins are essential micronutrients involved in various biochemical processes, such as serving as cofactors, antioxidants, and regulators of calcium metabolism. In vertebrates, vitamins D, K, and C are particularly known for supporting bone health and mineralization. However, the role of vitamins in biomineralization processes in marine invertebrates, such as octocorals (cnidarians) that produce internal skeletal structures called sclerites, remains largely unexplored.</div><div>This study uses an <em>in vivo</em> injection method in the octocoral <em>Sarcophyton sp</em>. to assess the effects of various vitamins on sclerite formation over 21 days. Calcification was monitored using calcein, a fluorescent marker, and analyzed by confocal microscopy combined with particle analysis. Our results indicate that vitamin D promotes sclerite formation, whereas vitamin C appears to inhibit this process, suggesting distinct roles for specific vitamins in octocoral biomineralization.</div><div>These findings provide experimental evidence of vitamin-mediated regulation of biomineralization in octocorals. By identifying conserved pathways in cnidarian skeletal formation, this study lays the groundwork for future research in coral physiology, and more broadly on comparative endocrinology, and may contribute to broader insights into coral resilience.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"375 ","pages":"Article 114854"},"PeriodicalIF":1.7,"publicationDate":"2025-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145512360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-08DOI: 10.1016/j.ygcen.2025.114849
James A. Carr
Neurons that produce proopiomelanocortin (POMC), and the biologically active peptides derived from POMC, play essential roles in feeding, body mass regulation and analgesia. Despite the documented importance of POMC peptides as neuromodulators there are only two populations of cells in the mammalian brain that synthesize this prohormone. POMC neurons in the arcuate nucleus of the hypothalamus have a well-documented role in the long-term control of food intake and body mass. Emerging work suggests an important role for the brainstem population of POMC neurons in the rapid control of food intake. There remain, however, many questions about the roles played by differentially processed forms of melanocortin and endorphin peptides. While we know with certainty that all gnathostomes have an infundibular POMC neuronal group, there are many unanswered questions about the evolution of these neurons and their role in long term energy storage and nutrient signaling. Almost nothing is known about brainstem POMC neurons in non-mammalian vertebrates or the anatomy of POMC neurons systems in agnathans. In this review I will summarize what we know about the location, post-translational processing, and function of POMC peptides in the vertebrate brain.
{"title":"Brain POMC Neurons: Comparative Aspects of Anatomy, Peptide Processing and Function","authors":"James A. Carr","doi":"10.1016/j.ygcen.2025.114849","DOIUrl":"10.1016/j.ygcen.2025.114849","url":null,"abstract":"<div><div>Neurons that produce proopiomelanocortin (POMC), and the biologically active peptides derived from POMC, play essential roles in feeding, body mass regulation and analgesia. Despite the documented importance of POMC peptides as neuromodulators there are only two populations of cells in the mammalian brain that synthesize this prohormone. POMC neurons in the arcuate nucleus of the hypothalamus have a well-documented role in the long-term control of food intake and body mass. Emerging work suggests an important role for the brainstem population of POMC neurons in the rapid control of food intake. There remain, however, many questions about the roles played by differentially processed forms of melanocortin and endorphin peptides. While we know with certainty that all gnathostomes have an infundibular POMC neuronal group, there are many unanswered questions about the evolution of these neurons and their role in long term energy storage and nutrient signaling. Almost nothing is known about brainstem POMC neurons in non-mammalian vertebrates or the anatomy of POMC neurons systems in agnathans. In this review I will summarize what we know about the location, post-translational processing, and function of POMC peptides in the vertebrate brain.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"375 ","pages":"Article 114849"},"PeriodicalIF":1.7,"publicationDate":"2025-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145488255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-08DOI: 10.1016/j.ygcen.2025.114850
Zhi Li , João C.R. Cardoso , Deborah M. Power
The Mollusca are the second most specious animal phyla after arthropods. They are morphologically diverse and exhibit high variability of their nervous systems, which have evolved as they adapted to an extreme range of ecological niches. Recent availability of genomes, transcriptomes and proteomes from diverse Mollusca representatives are uncovering the complexity of neuropeptides and their receptors. A diversity of neuropeptide precursors some of which encode multiple bioactive mature peptides and multiple orphan receptors have been described but their function is largely unexplored. This review will highlight the diversity of peptide/neuropeptide systems described in bivalves a member of the phylum Mollusca. The bivalves are of scientific and socioeconomic importance and in common with other calcifying marine organisms are susceptible to the effects of the rapidly changing global climate. Herein we briefly explore and compare mollusc nervous systems and highlight the complexity of bivalve peptide/neuropeptide genes, their putative receptor genes, and reports about their function in bivalve physiology. Characterization of the role of peptides/neuropeptides on bivalve physiology can give important insights into their evolutionary success but also feed models that can predict the likely impact of anthropogenic actions on their continuing success and biodiversity in a rapidly changing marine environment.
{"title":"Peptide and neuropeptide diversity and function in bivalves","authors":"Zhi Li , João C.R. Cardoso , Deborah M. Power","doi":"10.1016/j.ygcen.2025.114850","DOIUrl":"10.1016/j.ygcen.2025.114850","url":null,"abstract":"<div><div>The Mollusca are the second most specious animal phyla after arthropods. They are morphologically diverse and exhibit high variability of their nervous systems, which have evolved as they adapted to an extreme range of ecological niches. Recent availability of genomes, transcriptomes and proteomes from diverse Mollusca representatives are uncovering the complexity of neuropeptides and their receptors. A diversity of neuropeptide precursors some of which encode multiple bioactive mature peptides and multiple orphan receptors have been described but their function is largely unexplored. This review will highlight the diversity of peptide/neuropeptide systems described in bivalves a member of the phylum Mollusca. The bivalves are of scientific and socioeconomic importance and in common with other calcifying marine organisms are susceptible to the effects of the rapidly changing global climate. Herein we briefly explore and compare mollusc nervous systems and highlight the complexity of bivalve peptide/neuropeptide genes, their putative receptor genes, and reports about their function in bivalve physiology. Characterization of the role of peptides/neuropeptides on bivalve physiology can give important insights into their evolutionary success but also feed models that can predict the likely impact of anthropogenic actions on their continuing success and biodiversity in a rapidly changing marine environment.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"375 ","pages":"Article 114850"},"PeriodicalIF":1.7,"publicationDate":"2025-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145488235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-07DOI: 10.1016/j.ygcen.2025.114851
Diego J. Valdez , Gabriela C. López , Gabriel I. Boaglio , Diego R. Uñates , Leila M. López , Tomás C. Tempesti , Santiago M. Benitez-Vieyra , Gustavo M. Somoza
Avian reproduction is usually seasonal and strongly influenced by environmental factors, primarily photoperiod, which is mainly perceived by deep brain photoreceptors in the hypothalamic region and regulates the activation of the hypothalamic-pituitary–gonadal axis. However, certain species have developed adaptable reproductive strategies that differ from the classical seasonal model.
In this study, we analyzed seasonal variations and gonadal asymmetry in three dove species with different reproductive strategies: The White-tipped Dove (Leptotila verreauxi) and the Eared Dove (Zenaida auriculata), both native to South America, and the Rock Dove (Columba livia), an introduced species from the Northern Hemisphere.
Our results indicate that the White-tipped Dove, a seasonal breeder, follows a photoperiod-dependent reproductive pattern, showing seasonal variations in gonadal size and reproductive activity, as well as testosterone plasma levels, with no evidence of gonadal asymmetry. In the Eared Dove, an opportunistic breeder, the gonadal response is less pronounced, with testicular activity present even during months with short photoperiod, no association with testosterone plasma levels, and no gonadal asymmetry. Finally, the Rock Dove, another opportunistic breeder, exhibits the most variable gonadal response, with no association between photoperiod, gonadal morphology, and testosterone plasma levels.
These findings suggest that the White-tipped Dove follows a classical photoperiod-regulated seasonal reproductive cycle, whereas the Eared Dove and the Rock Dove display greater reproductive plasticity, likely influenced by other factors, such as anthropogenic food availability, rather than photoperiod.
{"title":"Seasonal vs opportunistic breeders, a seasonal morphological and endocrine comparative study of the gonadal cycle in birds","authors":"Diego J. Valdez , Gabriela C. López , Gabriel I. Boaglio , Diego R. Uñates , Leila M. López , Tomás C. Tempesti , Santiago M. Benitez-Vieyra , Gustavo M. Somoza","doi":"10.1016/j.ygcen.2025.114851","DOIUrl":"10.1016/j.ygcen.2025.114851","url":null,"abstract":"<div><div>Avian reproduction is usually seasonal and strongly influenced by environmental factors, primarily photoperiod, which is mainly perceived by deep brain photoreceptors in the hypothalamic region and regulates the activation of the hypothalamic-pituitary–gonadal axis. However, certain species have developed adaptable reproductive strategies that differ from the classical seasonal model.</div><div>In this study, we analyzed seasonal variations and gonadal asymmetry in three dove species with different reproductive strategies: The White-tipped Dove (<em>Leptotila verreauxi</em>) and the Eared Dove (<em>Zenaida auriculata</em>), both native to South America, and the Rock Dove (<em>Columba livia</em>), an introduced species from the Northern Hemisphere.</div><div>Our results indicate that the White-tipped Dove, a seasonal breeder, follows a photoperiod-dependent reproductive pattern, showing seasonal variations in gonadal size and reproductive activity, as well as testosterone plasma levels, with no evidence of gonadal asymmetry. In the Eared Dove, an opportunistic breeder, the gonadal response is less pronounced, with testicular activity present even during months with short photoperiod, no association with testosterone plasma levels, and no gonadal asymmetry. Finally, the Rock Dove, another opportunistic breeder, exhibits the most variable gonadal response, with no association between photoperiod, gonadal morphology, and testosterone plasma levels.</div><div>These findings suggest that the White-tipped Dove follows a classical photoperiod-regulated seasonal reproductive cycle, whereas the Eared Dove and the Rock Dove display greater reproductive plasticity, likely influenced by other factors, such as anthropogenic food availability, rather than photoperiod.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"375 ","pages":"Article 114851"},"PeriodicalIF":1.7,"publicationDate":"2025-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145481803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-06DOI: 10.1016/j.ygcen.2025.114841
Jiahui Du , Yicong Huang , Jiaqian Liao , Xianyuan Zeng , Pengfei Zou , Ziping Zhang , Yilei Wang
Scylla paramamosain, a vital marine economic crab species along the southeast coast of China, has been insufficiently studied regarding its reproductive regulation. Relaxin and its receptors play crucial roles in regulating animal reproductive processes. However, their functions and mechanisms of action in crustaceans remain unclear. In this study, two relaxin receptor-like proteins genes (SpRRLP) from S. paramamosain were cloned and designated as SpRRLP1 and SpRRLP2. Sequence analysis revealed that both belong to the C1 type of leucine-rich repeat type G-protein coupled receptors (LGR), with SpRRLP1 classified as an LGR4-type and SpRRLP2 as an RXFP/LGR3-type relaxin receptor. Temporal and spatial expression profiles demonstrated that both genes are most highly expressed in the ovary and eyestalk of mature crabs, with their expression levels significantly increasing during the middle and late stages of ovarian development. RNAi experiment combined with transcriptome analysis indicated that SpRRLP1 may be involved in ovarian development through pathways such as immunity, autophagy, and estrogen signaling, while SpRRLP2 primarily regulates ovarian development via pathways including the synthesis of sex steroid-like hormones and arachidonic acid metabolism. This study provides valuable insights into elucidating the mechanisms underlying gonadal development and reproductive regulation in crustaceans.
{"title":"Relaxin receptor-like proteins in Scylla paramamosain: Two distinct types and their roles in ovarian development","authors":"Jiahui Du , Yicong Huang , Jiaqian Liao , Xianyuan Zeng , Pengfei Zou , Ziping Zhang , Yilei Wang","doi":"10.1016/j.ygcen.2025.114841","DOIUrl":"10.1016/j.ygcen.2025.114841","url":null,"abstract":"<div><div><em>Scylla paramamosain</em>, a vital marine economic crab species along the southeast coast of China, has been insufficiently studied regarding its reproductive regulation. Relaxin and its receptors play crucial roles in regulating animal reproductive processes. However, their functions and mechanisms of action in crustaceans remain unclear. In this study, two relaxin receptor-like proteins genes (<em>SpRRLP</em>) from <em>S. paramamosain</em> were cloned and designated as <em>SpRRLP1</em> and <em>SpRRLP2</em>. Sequence analysis revealed that both belong to the C1 type of leucine-rich repeat type G-protein coupled receptors (LGR), with <em>Sp</em>RRLP1 classified as an LGR4-type and <em>Sp</em>RRLP2 as an RXFP/LGR3-type relaxin receptor. Temporal and spatial expression profiles demonstrated that both genes are most highly expressed in the ovary and eyestalk of mature crabs, with their expression levels significantly increasing during the middle and late stages of ovarian development. RNAi experiment combined with transcriptome analysis indicated that <em>Sp</em>RRLP1 may be involved in ovarian development through pathways such as immunity, autophagy, and estrogen signaling, while <em>Sp</em>RRLP2 primarily regulates ovarian development via pathways including the synthesis of sex steroid-like hormones and arachidonic acid metabolism. This study provides valuable insights into elucidating the mechanisms underlying gonadal development and reproductive regulation in crustaceans.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"375 ","pages":"Article 114841"},"PeriodicalIF":1.7,"publicationDate":"2025-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145476909","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-11-02DOI: 10.1016/j.ygcen.2025.114840
Subu Yatung, Lalmuanpuia Ralte, Amit Kumar Trivedi
In birds, stressors increase corticosterone, a glucocorticoid, causing physiological, reproductive, and behavioural changes. Besides, melatonin, a neurohormone produced by the pineal gland, regulates circadian rhythms and seasonal reproduction and exhibits antioxidant properties. In the present study, photorefractory adult male tree sparrows were used. Body mass, bill colour, and testicular volume were recorded. Later, birds (n = 6/group) were divided into three groups and were treated for 4 weeks under 8L:16D light conditions: Group 1 received ethanolic saline (control), group 2 received corticosterone (2 µg/100 µl), and group 3 received corticosterone (2 µg/100 µl) plus melatonin (10 µg/100 µl), with melatonin administered 30 min before lights-off. After 4 weeks of treatment, the birds were subsequently shifted to 16L:8D for 30 days. At the experiment’s end, samples were collected mid-light phase, and brain and testis tissues were stored at −80 °C for gene expression analysis. The study reveals no variation in the body mass and bill colour; however, testicular volume significantly increased across groups. Corticosterone treatment downregulated hypothalamic reproductive transcripts in tree sparrows, while the corticosterone plus melatonin and control groups showed upregulation of these genes. Furthermore, steroidogenic genes were downregulated in the testis of the corticosterone group compared with the other groups. Similarly, epigenetic genes (Hdac1, Hdac3, and Dnmt1) were upregulated in the hypothalamus in the corticosterone group; however, no changes were observed in the testis. These findings indicate corticosterone negatively impacts reproductive and steroidogenic activity in tree sparrows, but melatonin mitigates these effects, enhancing reproductive-linked steroidogenesis. This suggests a protective role of melatonin in counteracting corticosterone-induced reproductive suppression in this species.
{"title":"Melatonin modulates corticosterone-induced effects on steroidogenesis and reproductive-linked processes in male tree sparrow (passer montanus)","authors":"Subu Yatung, Lalmuanpuia Ralte, Amit Kumar Trivedi","doi":"10.1016/j.ygcen.2025.114840","DOIUrl":"10.1016/j.ygcen.2025.114840","url":null,"abstract":"<div><div>In birds, stressors increase corticosterone, a glucocorticoid, causing physiological, reproductive, and behavioural changes. Besides, melatonin, a neurohormone produced by the pineal gland, regulates circadian rhythms and seasonal reproduction and exhibits antioxidant properties. In the present study, photorefractory adult male tree sparrows were used. Body mass, bill colour, and testicular volume were recorded. Later, birds (n = 6/group) were divided into three groups and were treated for 4 weeks under 8L:16D light conditions: Group 1 received ethanolic saline (control), group 2 received corticosterone (2 µg/100 µl), and group 3 received corticosterone (2 µg/100 µl) plus melatonin (10 µg/100 µl), with melatonin administered 30 min before lights-off. After 4 weeks of treatment, the birds were subsequently shifted to 16L:8D for 30 days. At the experiment’s end, samples were collected mid-light phase, and brain and testis tissues were stored at −80 °C for gene expression analysis. The study reveals no variation in the body mass and bill colour; however, testicular volume significantly increased across groups. Corticosterone treatment downregulated hypothalamic reproductive transcripts in tree sparrows, while the corticosterone plus melatonin and control groups showed upregulation of these genes. Furthermore, steroidogenic genes were downregulated in the testis of the corticosterone group compared with the other groups. Similarly, epigenetic genes (<em>Hdac1</em>, <em>Hdac3</em>, and <em>Dnmt1</em>) were upregulated in the hypothalamus in the corticosterone group; however, no changes were observed in the testis. These findings indicate corticosterone negatively impacts reproductive and steroidogenic activity in tree sparrows, but melatonin mitigates these effects, enhancing reproductive-linked steroidogenesis. This suggests a protective role of melatonin in counteracting corticosterone-induced reproductive suppression in this species.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"375 ","pages":"Article 114840"},"PeriodicalIF":1.7,"publicationDate":"2025-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145444631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-31DOI: 10.1016/j.ygcen.2025.114839
Stefanny Christie Monteiro Titon , Braz Titon Junior , Vania Regina Assis , Alan Siqueira Lima , Fernando Ribeiro Gomes
Species with seasonal reproduction exhibit marked variations in physiological processes, including reproductive physiology and immune functions. In unpredictable situations, the emergency life-history stage is characterized by a stress response, primarily mediated by glucocorticoids, which regulate the balance between survival and reproduction. To better understand the impact of stressful events on endocrine and immune physiology in amphibians, we subjected male (calling or foraging) and female (foraging) toads (Rhinella diptycha) captured in the field during a reproductive event to a restraint protocol (0 h, 1 h, and 24 h, repeated samples). Before the restraint, a blood sample was collected to obtain reference values for plasma hormone levels (corticosterone, the main glucocorticoid in amphibians; testosterone; and estradiol) and immune measures (plasma bacterial killing ability and the neutrophil-to-lymphocyte ratio). Plasma corticosterone levels increased 1 and 24 h post-restraint in females and males (regardless of activity). We found decreased estradiol and testosterone plasma levels 24 h post-restraint, regardless of sex or activity. The plasma bacterial killing ability increased 1 h post-restraint in calling males and decreased 24 h post-restraint irrespective of sex or activity. The neutrophil to lymphocyte ratio increased only in foraging males 24 h post-restraint compared with 1 h post-restraint. These findings indicate that while corticosterone responses to acute stress are rapid and persist over time, the suppression of sex steroids and certain immune functions becomes more evident under prolonged stress exposure. Moreover, the transient enhancement of bacterial killing ability in calling males and the delayed increase in neutrophil-to-lymphocyte ratio in foraging males suggest that stress-induced immunomodulation may be influenced by reproductive behavior in R. diptycha.
{"title":"Reproductive status affects stress-induced hormonal and immune changes in male and female Rhinella diptycha toads","authors":"Stefanny Christie Monteiro Titon , Braz Titon Junior , Vania Regina Assis , Alan Siqueira Lima , Fernando Ribeiro Gomes","doi":"10.1016/j.ygcen.2025.114839","DOIUrl":"10.1016/j.ygcen.2025.114839","url":null,"abstract":"<div><div>Species with seasonal reproduction exhibit marked variations in physiological processes, including reproductive physiology and immune functions. In unpredictable situations, the emergency life-history stage is characterized by a stress response, primarily mediated by glucocorticoids, which regulate the balance between survival and reproduction. To better understand the impact of stressful events on endocrine and immune physiology in amphibians, we subjected male (calling or foraging) and female (foraging) toads (<em>Rhinella diptycha</em>) captured in the field during a reproductive event to a restraint protocol (0 h, 1 h, and 24 h, repeated samples). Before the restraint, a blood sample was collected to obtain reference values for plasma hormone levels (corticosterone, the main glucocorticoid in amphibians; testosterone; and estradiol) and immune measures (plasma bacterial killing ability and the neutrophil-to-lymphocyte ratio). Plasma corticosterone levels increased 1 and 24 h post-restraint in females and males (regardless of activity). We found decreased estradiol and testosterone plasma levels 24 h post-restraint, regardless of sex or activity. The plasma bacterial killing ability increased 1 h post-restraint in calling males and decreased 24 h post-restraint irrespective of sex or activity. The neutrophil to lymphocyte ratio increased only in foraging males 24 h post-restraint compared with 1 h post-restraint. These findings indicate that while corticosterone responses to acute stress are rapid and persist over time, the suppression of sex steroids and certain immune functions becomes more evident under prolonged stress exposure. Moreover, the transient enhancement of bacterial killing ability in calling males and the delayed increase in neutrophil-to-lymphocyte ratio in foraging males suggest that stress-induced immunomodulation may be influenced by reproductive behavior in <em>R. diptycha</em>.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"375 ","pages":"Article 114839"},"PeriodicalIF":1.7,"publicationDate":"2025-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145431204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-27DOI: 10.1016/j.ygcen.2025.114838
Bidisha Paul , Siyan Patel , Anna J. Taylor , Michael R. La Frano , Daniel R. Buchholz
Measurement of adrenal hormones in amphibians is important in studies on stress, development, osmoregulation, endocrine disruption, and conservation to help reveal mechanisms within amphibians and evolution among vertebrates. Corticosteroids measured in frogs are typically corticosterone and/or aldosterone, but steroid intermediates that may activate hormone receptors are thus far not quantified. Also, steroidogenesis in frogs has been examined in vitro but little work has been done using tadpoles with mutations affecting steroidogenesis. To advance such studies, we developed a comprehensive liquid chromatography − tandem mass spectrometry (LC-MS/MS) method to quantify 13 corticosteroid hormones and intermediates and 5 sex steroids in plasma and tail during natural metamorphosis and in pomc and cyp21a2 mutant tadpoles. Four of these steroids were consistently quantified in plasma and tail during development of wild-type tadpoles, namely 11-deoxycorticosterone (11-DOC), corticosterone (CORT), aldosterone (ALDO), and 11-dehydrocorticosterone (11-dehydroCORT). During metamorphosis, each of these steroids increased 4- to 5-fold in plasma, whereas in tail they were high during premetamorphosis and climax but lower in prometamorphosis. pomc mutant tails had only 2-fold less CORT, but cyp21a2 mutants also had an accumulation of progesterone and 11β-hydroxyprogesterone. This study revealed the in-vivo presence of 11-DOC, 11-dehydroCORT, and adrenal steroidogenic capacity in tadpoles and provided a comprehensive LC-MS/MS method for quantifying steroids relevant for a wide variety of studies.
{"title":"Comprehensive adrenal steroid profiling during frog metamorphosis","authors":"Bidisha Paul , Siyan Patel , Anna J. Taylor , Michael R. La Frano , Daniel R. Buchholz","doi":"10.1016/j.ygcen.2025.114838","DOIUrl":"10.1016/j.ygcen.2025.114838","url":null,"abstract":"<div><div>Measurement of adrenal hormones in amphibians is important in studies on stress, development, osmoregulation, endocrine disruption, and conservation to help reveal mechanisms within amphibians and evolution among vertebrates. Corticosteroids measured in frogs are typically corticosterone and/or aldosterone, but steroid intermediates that may activate hormone receptors are thus far not quantified. Also, steroidogenesis in frogs has been examined <em>in vitro</em> but little work has been done using tadpoles with mutations affecting steroidogenesis. To advance such studies, we developed a comprehensive liquid chromatography − tandem mass spectrometry (LC-MS/MS) method to quantify 13 corticosteroid hormones and intermediates and 5 sex steroids in plasma and tail during natural metamorphosis and in <em>pomc</em> and <em>cyp21a2</em> mutant tadpoles. Four of these steroids were consistently quantified in plasma and tail during development of wild-type tadpoles, namely 11-deoxycorticosterone (11-DOC), corticosterone (CORT), aldosterone (ALDO), and 11-dehydrocorticosterone (11-dehydroCORT). During metamorphosis, each of these steroids increased 4- to 5-fold in plasma, whereas in tail they were high during premetamorphosis and climax but lower in prometamorphosis. <em>pomc</em> mutant tails had only 2-fold less CORT, but <em>cyp21a2</em> mutants also had an accumulation of progesterone and 11β-hydroxyprogesterone. This study revealed the <em>in-vivo</em> presence of 11-DOC, 11-dehydroCORT, and adrenal steroidogenic capacity in tadpoles and provided a comprehensive LC-MS/MS method for quantifying steroids relevant for a wide variety of studies.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"375 ","pages":"Article 114838"},"PeriodicalIF":1.7,"publicationDate":"2025-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145384252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-24DOI: 10.1016/j.ygcen.2025.114837
Mark A. Sheridan, Andrea M. Hanson
Endocrine disrupting compounds (EDCs) from a variety of sources enter the terrestrial and aquatic environments and have deleterious effects on organisms, their progeny, and populations by altering the structure or function of endocrine systems. This review examines the effects of EDCs on organismal growth and the growth hormone (GH)/insulin-like growth factor (IGF) system in fish as well as the cellular mechanisms through which EDCs act on this system. The effects of EDCs on non-teleost vertebrates and on other growth regulating hormones also are briefly discussed. Accumulating evidence indicates that EDCs generally inhibit overall organismal growth of teleost fish in vivo, with some variability due to species, stage of development, specific compound, and mode and duration of exposure. The growth-retarding effects of EDC are accompanied by reduced food conversion, reduced body condition (i.e., condition factor), and reduced hepatosomatic index (HSI). In vivo exposure of euryhaline teleosts to EDCs also retards seawater (SW)-associated upregulation of GH-IGF system components (i.e., GH, GH receptors, IGFs, IGF receptors) and reduces SW adaptability. Accumulating evidence also indicates that EDCs generally inhibit various levels of the GH-IGF system, including GH production/secretion, tissue sensitivity to GH (i.e., GH receptor abundance), IGF production/secretion, IGF binding protein (IGFBP) production, and tissue sensitivity to IGF (i.e., IGF receptor abundance). There is some variability of response associated with species, developmental stage/sex of animals, specific EDC, mode or duration of exposure to EDC, and endpoint target (tissue and/or isoform of the GH/IGF system component). The effects of EDCs on GH-IGF system components are direct and result from effects on both rapid, non-genomic (e.g., JAK-STAT, PI3K/Akt, and ERK) and genomic mechanisms involving various transcription factors (e.g., AP-1, Sp1, Sp3, and MSY-1). EDC effects also may be transgenerational, affecting growth of offspring and other processes, including population dynamics. The wide-spread effects of EDCs continue to represent significant and lasting threats to the health and well-being of plants, animals and humans. This review represents a renewed call to action to regulate EDCs and to mitigate their deleterious effects now!
{"title":"Effects of endocrine disrupting compounds on growth and the growth hormone/insulin-like factor system of fish","authors":"Mark A. Sheridan, Andrea M. Hanson","doi":"10.1016/j.ygcen.2025.114837","DOIUrl":"10.1016/j.ygcen.2025.114837","url":null,"abstract":"<div><div>Endocrine disrupting compounds (EDCs) from a variety of sources enter the terrestrial and aquatic environments and have deleterious effects on organisms, their progeny, and populations by altering the structure or function of endocrine systems. This review examines the effects of EDCs on organismal growth and the growth hormone (GH)/insulin-like growth factor (IGF) system in fish as well as the cellular mechanisms through which EDCs act on this system. The effects of EDCs on non-teleost vertebrates and on other growth regulating hormones also are briefly discussed. Accumulating evidence indicates that EDCs generally inhibit overall organismal growth of teleost fish <em>in vivo</em>, with some variability due to species, stage of development, specific compound, and mode and duration of exposure. The growth-retarding effects of EDC are accompanied by reduced food conversion, reduced body condition (<em>i.e.</em>, condition factor), and reduced hepatosomatic index (HSI). <em>In vivo</em> exposure of euryhaline teleosts to EDCs also retards seawater (SW)-associated upregulation of GH-IGF system components (<em>i.e.</em>, GH, GH receptors, IGFs, IGF receptors) and reduces SW adaptability. Accumulating evidence also indicates that EDCs generally inhibit various levels of the GH-IGF system, including GH production/secretion, tissue sensitivity to GH (<em>i.e.</em>, GH receptor abundance), IGF production/secretion, IGF binding protein (IGFBP) production, and tissue sensitivity to IGF (<em>i.e.</em>, IGF receptor abundance). There is some variability of response associated with species, developmental stage/sex of animals, specific EDC, mode or duration of exposure to EDC, and endpoint target (tissue and/or isoform of the GH/IGF system component). The effects of EDCs on GH-IGF system components are direct and result from effects on both rapid, non-genomic (<em>e.g.</em>, JAK-STAT, PI3K/Akt, and ERK) and genomic mechanisms involving various transcription factors (<em>e.g.</em>, AP-1, Sp1, Sp3, and MSY-1). EDC effects also may be transgenerational, affecting growth of offspring and other processes, including population dynamics. The wide-spread effects of EDCs continue to represent significant and lasting threats to the health and well-being of plants, animals and humans. This review represents a renewed call to action to regulate EDCs and to mitigate their deleterious effects now!</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"375 ","pages":"Article 114837"},"PeriodicalIF":1.7,"publicationDate":"2025-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145621257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-10-20DOI: 10.1016/j.ygcen.2025.114836
José Alvenir Machado Pinto , Juliana Souza-Kasprzyk , Janeide de Assis Guilherme Padilha , Priscila Viau , João Paulo Machado Torres , Maria Alice S. Alves , Erli Schneider Costa
<div><div>Adverse environmental stimuli activate the hypothalamic–pituitary–adrenal axis, releasing corticosterone (CORT), the primary stress hormone in birds. This hormone facilitates adaptive responses to acute stressors, ensuring immediate survival but potentially compromising other vital functions when chronically elevated. In penguins, particularly those of the genus<!--> <em>Pygoscelis</em>, there is a striking lack of comparative data on stress physiology, especially for chicks, despite their ecological importance as bioindicators of Antarctic ecosystem change. Understanding species and age-specific stress responses is essential given their shared habitat, contrasting behavioral traits, and increasing exposure to climate change–related stressors. This study investigated the effects of capture and restraint on CORT concentrations in three sympatric penguin species: <em>P. adeliae</em> <!-->(Adélie),<!--> <em>P. papua</em> <!-->(Gentoo), and<!--> <em>P. antarcticus</em> <!-->(Chinstrap) nesting on King George Island, Antarctica. Blood samples were collected from adults and chicks of <em>P. adeliae</em> (n = 25 and n = 8) and <em>P. antarcticus</em> (n = 18 and n = 10), and from adults of <em>P. papua</em> (n = 18) at baseline (within 5 min of capture, CORT<sub>0</sub>) and after restraint for 30, 45, or 60 min (CORT<sub>30</sub>, CORT<sub>45</sub>, CORT<sub>60</sub>). Opportunistic urofecal samples (n = 36) were also analyzed from adults of the three species to compare excreted hormone levels with circulating one. All species showed a significant and non-linear increase in blood CORT following capture. Concentrations peaked at 30 min post-capture in <em>P. adeliae</em> <!-->and <em>P. Papua</em> which showed a pattern of initial increase followed by a temporary decline and secondary rise in corticosterone levels,<!--> <!-->whereas <em>P. antarcticus</em> <!-->had a more gradual and progressive increase over time peaking at 45 min. Interestingly,<!--> <em>P. antarcticus</em> <!-->chicks exhibited higher CORT<sub>0</sub> concentrations than adults, potentially reflecting greater reactivity to stress, whereas<!--> <em>P. adeliae</em> <!-->chicks showed values similar to adults, consistent with a maturing stress response. Urofecal CORT concentrations did not significantly differ among species but were consistently higher than baseline blood levels, likely reflecting integrated stress over time. This is the first study to compare baseline and stress-induced CORT concentrations across all three<!--> <em>Pygoscelis</em> <!-->species, to measure CORT in adults and chicks of<!--> <em>P. antarcticus</em>, and to analyze <em>Pygoscelis</em> populations from King George Island. By filling critical gaps in penguin stress physiology, these findings contribute to understanding interspecific and developmental variation in endocrine responses, confirm that capture and restraint significantly alter corticosterone levels and highlight the need for careful cons
{"title":"Comparative corticosterone responses to capture stress in sympatric Antarctic penguins","authors":"José Alvenir Machado Pinto , Juliana Souza-Kasprzyk , Janeide de Assis Guilherme Padilha , Priscila Viau , João Paulo Machado Torres , Maria Alice S. Alves , Erli Schneider Costa","doi":"10.1016/j.ygcen.2025.114836","DOIUrl":"10.1016/j.ygcen.2025.114836","url":null,"abstract":"<div><div>Adverse environmental stimuli activate the hypothalamic–pituitary–adrenal axis, releasing corticosterone (CORT), the primary stress hormone in birds. This hormone facilitates adaptive responses to acute stressors, ensuring immediate survival but potentially compromising other vital functions when chronically elevated. In penguins, particularly those of the genus<!--> <em>Pygoscelis</em>, there is a striking lack of comparative data on stress physiology, especially for chicks, despite their ecological importance as bioindicators of Antarctic ecosystem change. Understanding species and age-specific stress responses is essential given their shared habitat, contrasting behavioral traits, and increasing exposure to climate change–related stressors. This study investigated the effects of capture and restraint on CORT concentrations in three sympatric penguin species: <em>P. adeliae</em> <!-->(Adélie),<!--> <em>P. papua</em> <!-->(Gentoo), and<!--> <em>P. antarcticus</em> <!-->(Chinstrap) nesting on King George Island, Antarctica. Blood samples were collected from adults and chicks of <em>P. adeliae</em> (n = 25 and n = 8) and <em>P. antarcticus</em> (n = 18 and n = 10), and from adults of <em>P. papua</em> (n = 18) at baseline (within 5 min of capture, CORT<sub>0</sub>) and after restraint for 30, 45, or 60 min (CORT<sub>30</sub>, CORT<sub>45</sub>, CORT<sub>60</sub>). Opportunistic urofecal samples (n = 36) were also analyzed from adults of the three species to compare excreted hormone levels with circulating one. All species showed a significant and non-linear increase in blood CORT following capture. Concentrations peaked at 30 min post-capture in <em>P. adeliae</em> <!-->and <em>P. Papua</em> which showed a pattern of initial increase followed by a temporary decline and secondary rise in corticosterone levels,<!--> <!-->whereas <em>P. antarcticus</em> <!-->had a more gradual and progressive increase over time peaking at 45 min. Interestingly,<!--> <em>P. antarcticus</em> <!-->chicks exhibited higher CORT<sub>0</sub> concentrations than adults, potentially reflecting greater reactivity to stress, whereas<!--> <em>P. adeliae</em> <!-->chicks showed values similar to adults, consistent with a maturing stress response. Urofecal CORT concentrations did not significantly differ among species but were consistently higher than baseline blood levels, likely reflecting integrated stress over time. This is the first study to compare baseline and stress-induced CORT concentrations across all three<!--> <em>Pygoscelis</em> <!-->species, to measure CORT in adults and chicks of<!--> <em>P. antarcticus</em>, and to analyze <em>Pygoscelis</em> populations from King George Island. By filling critical gaps in penguin stress physiology, these findings contribute to understanding interspecific and developmental variation in endocrine responses, confirm that capture and restraint significantly alter corticosterone levels and highlight the need for careful cons","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"374 ","pages":"Article 114836"},"PeriodicalIF":1.7,"publicationDate":"2025-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145336620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号