Pub Date : 2025-08-09DOI: 10.1016/j.ygcen.2025.114797
Abigayle M. McKinley, Carol Best, Nicholas J. Bernier
Scale cortisol has the potential to be a useful biomarker of chronic stress in fish, but the dynamics of scale cortisol accumulation and release are not well understood. In this study, we assessed the dynamics of plasma and scale cortisol accumulation and clearance in green sunfish (Lepomis cyanellus) in response to acute and chronic stressors. While sunfish exposed to 21 days of unpredictable chronic stress (UCS) mounted an attenuated acute plasma cortisol response to the daily stressor on day 21 and had reduced liver and body conditions, their scale cortisol content was either unchanged or reduced. In contrast, exposure to an acute stressor increased scale cortisol content 30 min post-stressor in naïve fish but had no effect when preceded by the 21-day UCS protocol. We also examined the effects of an acute stressor on scale cortisol content in goldfish (Carassius auratus) to identify potential species differences in scale cortisol dynamics. Interestingly, although an acute stressor increased scale cortisol content 30 min post-stressor and declined 24 h later in both species, only sunfish scale cortisol levels returned to baseline by 24 h post-stressor. Together, our results indicate that scales in green sunfish can accumulate and clear cortisol rapidly following an acute stressor and do not reflect long-term accumulation of cortisol from the plasma during chronic stress. As such, we conclude that scale cortisol content is not a biomarker of chronic stress in green sunfish.
{"title":"Scale cortisol reflects the acute but not the chronic stress status in green sunfish (Lepomis cyanellus)","authors":"Abigayle M. McKinley, Carol Best, Nicholas J. Bernier","doi":"10.1016/j.ygcen.2025.114797","DOIUrl":"10.1016/j.ygcen.2025.114797","url":null,"abstract":"<div><div>Scale cortisol has the potential to be a useful biomarker of chronic stress in fish, but the dynamics of scale cortisol accumulation and release are not well understood. In this study, we assessed the dynamics of plasma and scale cortisol accumulation and clearance in green sunfish (<em>Lepomis cyanellus</em>) in response to acute and chronic stressors. While sunfish exposed to 21 days of unpredictable chronic stress (UCS) mounted an attenuated acute plasma cortisol response to the daily stressor on day 21 and had reduced liver and body conditions, their scale cortisol content was either unchanged or reduced. In contrast, exposure to an acute stressor increased scale cortisol content 30 min post-stressor in naïve fish but had no effect when preceded by the 21-day UCS protocol. We also examined the effects of an acute stressor on scale cortisol content in goldfish (<em>Carassius auratus</em>) to identify potential species differences in scale cortisol dynamics. Interestingly, although an acute stressor increased scale cortisol content 30 min post-stressor and declined 24 h later in both species, only sunfish scale cortisol levels returned to baseline by 24 h post-stressor. Together, our results indicate that scales in green sunfish can accumulate and clear cortisol rapidly following an acute stressor and do not reflect long-term accumulation of cortisol from the plasma during chronic stress. As such, we conclude that scale cortisol content is not a biomarker of chronic stress in green sunfish.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"372 ","pages":"Article 114797"},"PeriodicalIF":1.7,"publicationDate":"2025-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144821184","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 : 2025-07-23DOI: 10.1016/j.ygcen.2025.114787
Na Liu , Mengjie Li , Tianci Liu , Jitu Wang , Bo Zhang , Man Zhang
Background
In our previous study, Phosphofructokinase, muscle (PFKM), a key enzyme in glucose metabolism, was found to be decreased in the urinary exosomes of diabetic patients. The role of PFKM in glucose and energy metabolism is not fully understood. The study explores PFKM’s implications in these metabolic pathways through the lens of a zebrafish model.
Methods
We analyzed pfkma and pfkmb expressions in early zebrafish development using Daniocell and ZESTA databases and performed whole-mount in situ hybridization on embryos up to 4 days post-fertilization (dpf). The CRISPR/Cas9 system was utilized to generate pfkma and pfkmb knockout zebrafish, and the expression of various genes, including β-actin, pfkma, pfkmb, peo1, mfn1, drp1, nd2, cytb, cox3, and atp6, was measured by qRT-PCR in the embryos.
Results
Knockout mutants displayed elevated glucose levels across whole embryos. Additionally, at 5 dpf, pfkma and pfkmb double mutants showed pancreatic islet proliferation, ATP depletion, downregulation of the expression of the mitochondrial-related gene peo1, and impaired locomotor activity.
Conclusions
PFKM plays an important role in stabilizing glucose metabolism and has a certain impact on mitochondrial energy metabolism pathways in zebrafish model.
{"title":"Disorders of glucose metabolism and impaired energy metabolism in pfkma and pfkmb knockout zebrafish","authors":"Na Liu , Mengjie Li , Tianci Liu , Jitu Wang , Bo Zhang , Man Zhang","doi":"10.1016/j.ygcen.2025.114787","DOIUrl":"10.1016/j.ygcen.2025.114787","url":null,"abstract":"<div><h3>Background</h3><div>In our previous study, Phosphofructokinase, muscle (PFKM), a key enzyme in glucose metabolism, was found to be decreased in the urinary exosomes of diabetic patients. The role of PFKM in glucose and energy metabolism is not fully understood. The study explores PFKM’s implications in these metabolic pathways through the lens of a zebrafish model.</div></div><div><h3>Methods</h3><div>We analyzed <em>pfkma</em> and <em>pfkmb</em> expressions in early zebrafish development using Daniocell and ZESTA databases and performed whole-mount <em>in situ</em> hybridization on embryos up to 4 days post-fertilization (dpf). The CRISPR/Cas9 system was utilized to generate <em>pfkma</em> and <em>pfkmb</em> knockout zebrafish, and the expression of various genes, including <em>β-actin, pfkma, pfkmb, peo1, mfn1, drp1, nd2, cytb, cox3,</em> and <em>atp6</em>, was measured by qRT-PCR in the embryos.</div></div><div><h3>Results</h3><div>Knockout mutants displayed elevated glucose levels across whole embryos. Additionally, at 5 dpf, <em>pfkma</em> and <em>pfkmb</em> double mutants showed pancreatic islet proliferation, ATP depletion, downregulation of the expression of the mitochondrial-related gene <em>peo1,</em> and impaired locomotor activity.</div></div><div><h3>Conclusions</h3><div>PFKM plays an important role in stabilizing glucose metabolism and has a certain impact on mitochondrial energy metabolism pathways in zebrafish model.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"372 ","pages":"Article 114787"},"PeriodicalIF":1.7,"publicationDate":"2025-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144717820","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 : 2025-07-18DOI: 10.1016/j.ygcen.2025.114788
Ana M. Pahí-Rosero , Gabriela C. López , María R. Pérez , Alejandro S. Mechaly , Takayoshi Ubuka , José A. Muñoz-Cueto , Paula G. Vissio , Gustavo M. Somoza
The gonadotropin-inhibitory hormone is a neuropeptide belonging to the RF-amide family of peptides, first characterized in birds. This peptide can inhibit the synthesis and release of gonadotropins in both avians and mammals. Although gonadotropin-inhibitory hormone (Gnih) variants have also been detected in different fish species, knowledge of their physiological action is still inconclusive and controversial. In addition, there is very little information on the neuronal development of Gnih cells in early stages. In this context, the objective of the present study is to characterize Gnih-containing neurons and fibers in the brain and pituitary gland of adult fish, and during early development of the pejerrey (Odontesthes bonariensis), and the possible relationship with the sex differentiation process.
The Gnih neurons and fibers were determined by immunohistochemistry by using different antisera in the adult pejerrey brain. Gnih-immunoreactive (Gnih-ir) neurons were observed in the olfactory bulbs, the terminal nerve ganglion, the lateral nuclei of the ventral telencephalon, the posterior periventricular nucleus, the dorsal tegmentum, and some isolated neuronal bodies were detected in the secondary gustatory nucleus. Very few Gnih-ir fibers were detected innervating the pituitary gland.
The Gnih neuronal and fiber distribution was also studied from hatching to week 10, covering the sex differentiation period until the gonadal sex was observed. Gnih-immunoreactive neuronal bodies were identified from hatching in the terminal nerve ganglion and the diencephalic posterior periventricular nucleus. Gnih-ir fibers were observed in many regions, including the retina, and a profuse innervation was observed in the pituitary. From the first week post-hatching, Gnih-ir neuronal bodies were identified in the dorsal mesencephalic tegmentum and the lateral nucleus of the ventral telencephalon. In addition, Gnih-ir cells were detected in the pituitary. These Gnih-ir cells were consistently detected from 3 to 7 weeks after hatching, coinciding with onset of gonadal differentiation. At week 10 and in the adult, only a few Gnih-ir fibers were observed in the pituitary. Although the precise function of these pituitary Gnih-ir cells is unknown, the relationship between the appearance of these cells and the process of sex differentiation suggests that Gnih may influence this process.
{"title":"Ontogeny of gonadotropin-inhibitory hormone cells and fibers in the brain and pituitary gland of the pejerrey fish, Odontesthes bonariensis","authors":"Ana M. Pahí-Rosero , Gabriela C. López , María R. Pérez , Alejandro S. Mechaly , Takayoshi Ubuka , José A. Muñoz-Cueto , Paula G. Vissio , Gustavo M. Somoza","doi":"10.1016/j.ygcen.2025.114788","DOIUrl":"10.1016/j.ygcen.2025.114788","url":null,"abstract":"<div><div>The gonadotropin-inhibitory hormone is a neuropeptide belonging to the RF-amide family of peptides, first characterized in birds. This peptide can inhibit the synthesis and release of gonadotropins in both avians and mammals. Although gonadotropin-inhibitory hormone (Gnih) variants have also been detected in different fish species, knowledge of their physiological action is still inconclusive and controversial. In addition, there is very little information on the neuronal development of Gnih cells in early stages. In this context, the objective of the present study is to characterize Gnih-containing neurons and fibers in the brain and pituitary gland of adult fish, and during early development of the pejerrey (<em>Odontesthes bonariensis</em>), and the possible relationship with the sex differentiation process.</div><div>The Gnih neurons and fibers were determined by immunohistochemistry by using different antisera in the adult pejerrey brain. Gnih-immunoreactive (Gnih-ir) neurons were observed in the olfactory bulbs, the terminal nerve ganglion, the lateral nuclei of the ventral telencephalon, the posterior periventricular nucleus, the dorsal tegmentum, and some isolated neuronal bodies were detected in the secondary gustatory nucleus. Very few Gnih-ir fibers were detected innervating the pituitary gland.</div><div>The Gnih neuronal and fiber distribution was also studied from hatching to week 10, covering the sex differentiation period until the gonadal sex was observed. Gnih-immunoreactive neuronal bodies were identified from hatching in the terminal nerve ganglion and the diencephalic posterior periventricular nucleus. Gnih-ir fibers were observed in many regions, including the retina, and a profuse innervation was observed in the pituitary. From the first week post-hatching, Gnih-ir neuronal bodies were identified in the dorsal mesencephalic tegmentum and the lateral nucleus of the ventral telencephalon. In addition, Gnih-ir cells were detected in the pituitary. These Gnih-ir cells were consistently detected from 3 to 7 weeks after hatching, coinciding with onset of gonadal differentiation. At week 10 and in the adult, only a few Gnih-ir fibers were observed in the pituitary. Although the precise function of these pituitary Gnih-ir cells is unknown, the relationship between the appearance of these cells and the process of sex differentiation suggests that Gnih may influence this process.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"372 ","pages":"Article 114788"},"PeriodicalIF":2.1,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144665536","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}
Polycyclic aromatic hydrocarbons (PAHs), considered endocrine disruptors, affect the animals reproduction by interfering with the production of sex steroids. In the present study, the in vitro effects of selected PAHs (naphthalene, phenanthrene and BaP) on steroid production of cultivated ovarian cells from Arabian sea bream (Acanthopagrus arabicus) was assessed. Ovarian cells were cultured in Leibovitz L-15 (L-15) medium containing naphthalene, phenanthrene and benzo(a)pyrene with or without androstenedione (AD) as precursors and17b-estradiol (E2), progesterone (P4) and testosterone (T) were then measured. The effects of selected PAHs on the steroidogenic enzyme systems cytochrome P450 17, 20-lyase (P450-17,20l) and cytochrome P450 aromatase (P450-arom) were also compared with the ketoconazole (KCZ) action as inhibitor of cytochrome P450 steroidogenic enzymes (cytochrome P450 17, 20-lyase (P450-17,20l)) and cytochrome P450 aromatase (P450-arom). Adding exogenous androstenedione as a steroid precursor significantly increased the production of all three steroid hormones by cultured ovarian cells. On the other hand, the addition of ketoconazole significantly reduced the production of E2 and P from ovarian cells, while it had no effect on the production of T. This result showed that ketoconazole only affects the cytochrome P450 steroidogenic enzymes and has no effect on the 17-beta-hydroxysteroid dehydrogenase (17-βHSD) enzyme that convert androstenedione to testosterone. On the other hand, a significant decrease in the production of all three steroids (17β-estradiol, progesterone, and testosterone) from ovarian cells exposed to the studied pollutants (naphthalene, phenanthrene, and benzo(a)pyrene) even in the presence of androstenedione indicated that PAHs inhibit all three steroidogenic enzyme systems including P450-17,20l, P450-arom, and 17b-HSD. In conclusion, PAHs are potent inhibitors of the steroidogenic enzyme system including P450-17,20l, P450-arom, and 17b-HSD, and therefore, they can disturb the reproduction of fish living in contaminated areas due to impairment of steroid biosynthesis.
{"title":"In vitro effects of polycyclic aromatic hydrocarbons on sex steroid production by Arabian sea bream Acanthopagrus arabicus ovarian cells","authors":"Fereshteh Aysham , Negin Salamat , Alireza Safahieh , Arash Larki , Asma Mohammadi","doi":"10.1016/j.ygcen.2025.114778","DOIUrl":"10.1016/j.ygcen.2025.114778","url":null,"abstract":"<div><div>Polycyclic aromatic hydrocarbons (PAHs), considered endocrine disruptors, affect the animals reproduction by interfering with the production of sex steroids. In the present study, the in vitro effects of selected PAHs (naphthalene, phenanthrene and BaP) on steroid production of cultivated ovarian cells from Arabian sea bream (<em>Acanthopagrus arabicus</em>) was assessed. Ovarian cells were cultured in Leibovitz L-15 (L-15) medium containing naphthalene, phenanthrene and benzo(a)pyrene with or without androstenedione (AD) as precursors and17b-estradiol (E2), progesterone (P4) and testosterone (T) were then measured. The effects of selected PAHs on the steroidogenic enzyme systems cytochrome P450 17, 20-lyase (P450-17,20l) and cytochrome P450 aromatase (P450-arom) were also compared with the ketoconazole (KCZ) action as inhibitor of cytochrome P450 steroidogenic enzymes (cytochrome P450 17, 20-lyase (P450-17,20l)) and cytochrome P450 aromatase (P450-arom). Adding exogenous androstenedione as a steroid precursor significantly increased the production of all three steroid hormones by cultured ovarian cells. On the other hand, the addition of ketoconazole significantly reduced the production of E2 and P from ovarian cells, while it had no effect on the production of T. This result showed that ketoconazole only affects the cytochrome P450 steroidogenic enzymes and has no effect on the 17-beta-hydroxysteroid dehydrogenase (17-βHSD) enzyme that convert androstenedione to testosterone. On the other hand, a significant decrease in the production of all three steroids (17β-estradiol, progesterone, and testosterone) from ovarian cells exposed to the studied pollutants (naphthalene, phenanthrene, and benzo(a)pyrene) even in the presence of androstenedione indicated that PAHs inhibit all three steroidogenic enzyme systems including P450-17,20l, P450-arom, and 17b-HSD. In conclusion, PAHs are potent inhibitors of the steroidogenic enzyme system including P450-17,20l, P450-arom, and 17b-HSD, and therefore, they can disturb the reproduction of fish living in contaminated areas due to impairment of steroid biosynthesis.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"371 ","pages":"Article 114778"},"PeriodicalIF":2.1,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144579745","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 : 2025-07-05DOI: 10.1016/j.ygcen.2025.114777
Kenji Toyota , Asami Kajimoto , Yushi Ando , Ken Takeuchi , Tsuyoshi Ohira
The horsehair crab Erimacrus isenbeckii is widely distributed from Alaska and the Bering Sea through Southern Sakhalin, and in Japan from the coastal areas of Hokkaido to the Sea of Japan. In the Hokkaido area, although strict resource management has been promoted by setting an allowable catch limit, the catch amount has remained at a low level. While knowledge on larval rearing methods is accumulating in relation to seedling production techniques, information on adult growth and molting is limited, due to a deep-sea species that requires a long period for growth. In decapod crustaceans, the sinus-gland/X-organ complex in the eyestalk ganglion synthesizes and secrets various neuropeptides such as crustacean hyperglycemic hormone (CHH) to regulate the homeostasis of haemolymph glucose levels. In this study, combined isolation of sinus gland peptides by reverse-phase high-performance liquid chromatography (RP-HPLC) and amino acid sequencing, and transcriptome analyses using male and female eyestalk ganglion has been successfully identified EiCHHa. In adult male E. isenbeckii, no decrease in haemolymph glucose levels was observed following bilateral eyestalk ablation, indicating that this treatment does not affect glucose homeostasis in this species. Therefore, the in vivo assays of EiCHHa using the blue swimming crab Portunus pelagicus revealed EiCHHa has a hyperglycemic effect, as well as CHHs in other decapod crustaceans. On the other hand, EiCHHa-injected red swamp crayfish Procambarus clarkii with bilateral eyestalk ablation showed no significant increase in hemolymph glucose levels. Additionally, we successfully demonstrated the sexual differences in the transcriptomic profiles between males and females. Especially, two sinus gland-derived neuropeptides (EiCHHb and a crustacean female sex hormone (EiCFSH)) were isolated as female-biased transcripts, suggesting that both hormones may have female-specific roles such as the development of female characteristics and reproduction.
{"title":"Characterization of a crustacean hyperglycemic hormone of the horsehair crab Erimacrus isenbeckii","authors":"Kenji Toyota , Asami Kajimoto , Yushi Ando , Ken Takeuchi , Tsuyoshi Ohira","doi":"10.1016/j.ygcen.2025.114777","DOIUrl":"10.1016/j.ygcen.2025.114777","url":null,"abstract":"<div><div>The horsehair crab <em>Erimacrus isenbeckii</em> is widely distributed from Alaska and the Bering Sea through Southern Sakhalin, and in Japan from the coastal areas of Hokkaido to the Sea of Japan. In the Hokkaido area, although strict resource management has been promoted by setting an allowable catch limit, the catch amount has remained at a low level. While knowledge on larval rearing methods is accumulating in relation to seedling production techniques, information on adult growth and molting is limited, due to a deep-sea species that requires a long period for growth. In decapod crustaceans, the sinus-gland/X-organ complex in the eyestalk ganglion synthesizes and secrets various neuropeptides such as crustacean hyperglycemic hormone (CHH) to regulate the homeostasis of haemolymph glucose levels. In this study, combined isolation of sinus gland peptides by reverse-phase high-performance liquid chromatography (RP-HPLC) and amino acid sequencing, and transcriptome analyses using male and female eyestalk ganglion has been successfully identified EiCHHa. In adult male <em>E</em>. <em>isenbeckii</em>, no decrease in haemolymph glucose levels was observed following bilateral eyestalk ablation, indicating that this treatment does not affect glucose homeostasis in this species. Therefore, the <em>in vivo</em> assays of EiCHHa using the blue swimming crab <em>Portunus pelagicus</em> revealed EiCHHa has a hyperglycemic effect, as well as CHHs in other decapod crustaceans. On the other hand, EiCHHa-injected red swamp crayfish <em>Procambarus clarkii</em> with bilateral eyestalk ablation showed no significant increase in hemolymph glucose levels. Additionally, we successfully demonstrated the sexual differences in the transcriptomic profiles between males and females. Especially, two sinus gland-derived neuropeptides (EiCHHb and a crustacean female sex hormone (EiCFSH)) were isolated as female-biased transcripts, suggesting that both hormones may have female-specific roles such as the development of female characteristics and reproduction.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"371 ","pages":"Article 114777"},"PeriodicalIF":2.1,"publicationDate":"2025-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144571801","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 : 2025-06-30DOI: 10.1016/j.ygcen.2025.114776
Rodrigo Zuloaga , Alfredo Molina , Juan Antonio Valdés
The 11-deoxycorticosterone (DOC) corticosteroid has been recently described as having a potential role in fish, complementing cortisol action through distinct physiological effects. Although systemic effects of 11-deoxycorticosterone (DOC) have been reported, the specific mechanisms mediated through glucocorticoid (GR) and mineralocorticoid (MR) receptors remain poorly understood. Therefore, we evaluated the DOC effects through both receptors in rainbow trout hepatoma-derived (RTH-149) and gill epithelial (RTgill-W1) cell lines. Cultures were pretreated with GR (Mifepristone) or MR (Eplerenone) antagonists for 1 h (50 nM) and then with DOC (10 nM) or vehicle (DMSO-PBS1X) as control for 3 h (n = 3). First, to determine a DOC-induced response via GR or MR, we detected a decrease in transcriptional levels of mr and these results were recovered to basal levels by MR antagonist in both cell lines. Then, we evaluated different metabolites and solutes associated with carbohydrate metabolism in RTH-149 and osmoregulation in RTgill-W1, detecting that DOC through both GR and MR differentially modulates lactate, glycogen, calcium, and chloride levels. We also identified that DOC mainly by MR differentially regulates gene expression of glucose/glycogen metabolism in RTH-149, ionic cotransporters, and tight junction proteins in RTgill-W1. Subsequently, we determined that DOC significantly decreases glucose uptake in RTH-149 and apparent permeability in RTgill-W1, reversed by MR antagonist. However, DOC does not affect transepithelial resistance in RTgill-W1. This study provides the first evidence that DOC, primarily via MR, plays a role in regulating carbohydrate metabolism in fish hepatocytes and osmoregulation in gill epithelial cells.
{"title":"In vitro effects of 11-deoxycorticosterone on hepatocytes and gill epithelial cells of rainbow trout (Oncorhynchus mykiss)","authors":"Rodrigo Zuloaga , Alfredo Molina , Juan Antonio Valdés","doi":"10.1016/j.ygcen.2025.114776","DOIUrl":"10.1016/j.ygcen.2025.114776","url":null,"abstract":"<div><div>The 11-deoxycorticosterone (DOC) corticosteroid has been recently described as having a potential role in fish, complementing cortisol action through distinct physiological effects. Although systemic effects of 11-deoxycorticosterone (DOC) have been reported, the specific mechanisms mediated through glucocorticoid (GR) and mineralocorticoid (MR) receptors remain poorly understood. Therefore, we evaluated the DOC effects through both receptors in rainbow trout hepatoma-derived (RTH-149) and gill epithelial (RTgill-W1) cell lines. Cultures were pretreated with GR (Mifepristone) or MR (Eplerenone) antagonists for 1 h (50 nM) and then with DOC (10 nM) or vehicle (DMSO-PBS1X) as control for 3 h (n = 3). First, to determine a DOC-induced response via GR or MR, we detected a decrease in transcriptional levels of <em>mr</em> and these results were recovered to basal levels by MR antagonist in both cell lines. Then, we evaluated different metabolites and solutes associated with carbohydrate metabolism in RTH-149 and osmoregulation in RTgill-W1, detecting that DOC through both GR and MR differentially modulates lactate, glycogen, calcium, and chloride levels. We also identified that DOC mainly by MR differentially regulates gene expression of glucose/glycogen metabolism in RTH-149, ionic cotransporters, and tight junction proteins in RTgill-W1. Subsequently, we determined that DOC significantly decreases glucose uptake in RTH-149 and apparent permeability in RTgill-W1, reversed by MR antagonist. However, DOC does not affect transepithelial resistance in RTgill-W1. This study provides the first evidence that DOC, primarily via MR, plays a role in regulating carbohydrate metabolism in fish hepatocytes and osmoregulation in gill epithelial cells.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"371 ","pages":"Article 114776"},"PeriodicalIF":2.1,"publicationDate":"2025-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144524004","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 : 2025-06-27DOI: 10.1016/j.ygcen.2025.114775
J. Sivan , A.A. Degen , S.J.A. Horesh , I. Tesler , S. Hadad , H. Boni , M. Kam
Testosterone levels have been linked to reproduction and locomotor activities in vertebrates and even to some invertebrates. However, the relationship between testosterone concentration and daily distance travelled (DDT) in a free-ranging reptile has not been tested. The aim of this study was to fill this gap. Seasonal plasma testosterone concentration in the free-ranging male Saharan sand viper, Cerastes vipera, was reported to be bimodal: a large peak in spring during spermatogenesis and mating, and a small peak in autumn, during spermatogenesis but without mating prior to hibernation. We hypothesized that DDT would be bimodal as well, the pattern coinciding with testosterone concentration. To test this hypothesis, we measured monthly DDT in free-ranging C. vipera of the same population at the same site, and compared the pattern with that of plasma testosterone concentrations reported earlier. A bimodal pattern in DDT was observed that coincided with testosterone concentration, and, therefore, our hypothesis was supported. This is the first study demonstrating a link between plasma testosterone concentration and DDT in a free-ranging animal; however, the link is correlational as there was no manipulation and cannot be attributed to a casual effect. Further studies are warranted to clarify the relationship between testosterone level and DDT.
{"title":"Testosterone concentration coincides with distance travelled in the free-ranging male Saharan sand-viper, Cerastes vipera","authors":"J. Sivan , A.A. Degen , S.J.A. Horesh , I. Tesler , S. Hadad , H. Boni , M. Kam","doi":"10.1016/j.ygcen.2025.114775","DOIUrl":"10.1016/j.ygcen.2025.114775","url":null,"abstract":"<div><div>Testosterone levels have been linked to reproduction and locomotor activities in vertebrates and even to some invertebrates. However, the relationship between testosterone concentration and daily distance travelled (DDT) in a free-ranging reptile has not been tested. The aim of this study was to fill this gap. Seasonal plasma testosterone concentration in the free-ranging male Saharan sand viper, <em>Cerastes vipera</em>, was reported to be bimodal: a large peak in spring during spermatogenesis and mating, and a small peak in autumn, during spermatogenesis but without mating prior to hibernation. We hypothesized that DDT would be bimodal as well, the pattern coinciding with testosterone concentration. To test this hypothesis, we measured monthly DDT in free-ranging <em>C. vipera</em> of the same population at the same site, and compared the pattern with that of plasma testosterone concentrations reported earlier. A bimodal pattern in DDT was observed that coincided with testosterone concentration, and, therefore, our hypothesis was supported. This is the first study demonstrating a link between plasma testosterone concentration and DDT in a free-ranging animal; however, the link is correlational as there was no manipulation and cannot be attributed to a casual effect. Further studies are warranted to clarify the relationship between testosterone level and DDT.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"371 ","pages":"Article 114775"},"PeriodicalIF":2.1,"publicationDate":"2025-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144517919","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 : 2025-06-26DOI: 10.1016/j.ygcen.2025.114773
Mauro Chivite-Alcalde , Brett M. Culbert , Shayla Larson-Hossack , Jesús M. Míguez , Nicholas J. Bernier
Ammonia is neurotoxic and exposure to high environmental ammonia (HEA) activates the hypothalamic-pituitary-interrenal (HPI) axis in teleosts. To gain insight into the neural factors that regulate the HPI axis in response to this environmental stressor, as well as elucidate potential interactions between these factors, we exposed rainbow trout to one of three ammonia levels (0, 650, 1000 μM NH4Cl) for 24 or 96 h and assessed the gene expression and circulating levels of key determinants of HPI axis activity. In parallel with circulating ammonia concentrations, plasma cortisol levels increased dose-dependently after 24 h of HEA exposure and partially recovered after 96 h. HEA exposure also elicited dose-, time-, and brain region-specific changes in components of the central serotonergic (5-HTergic; tph2, htr1aa, htr1b, htr2c), corticotropin-releasing factor (crfb), arginine vasotocin (avt, avtr1a, avtr2), and isotocin (it, itr) signaling systems. Moreover, while intraperitoneal injections of 5-HT1B and 5-HT2C receptor antagonists reduced basal cortisol levels, treatment with 5-HT1A and 5-HT2C receptor antagonists blocked the increase in plasma cortisol elicited by HEA. Finally, treatment with specific 5-HT receptor antagonists blunted the HEA-induced increases in brain preoptic area crfb, avt, and it expression. These findings implicate 5-HT and multiple peptidergic systems in the hypophysiotropic regulation of the HPI axis in response to HEA exposure and provide novel insight into the multifactorial neural circuitry mediating the neuroendocrine stress response in fishes.
{"title":"Regulation of the neuroendocrine stress axis in response to ammonia exposure in rainbow trout: Pharmacological and transcriptional evidence implicating serotonin and multiple hypophysiotropic peptides","authors":"Mauro Chivite-Alcalde , Brett M. Culbert , Shayla Larson-Hossack , Jesús M. Míguez , Nicholas J. Bernier","doi":"10.1016/j.ygcen.2025.114773","DOIUrl":"10.1016/j.ygcen.2025.114773","url":null,"abstract":"<div><div>Ammonia is neurotoxic and exposure to high environmental ammonia (HEA) activates the hypothalamic-pituitary-interrenal (HPI) axis in teleosts. To gain insight into the neural factors that regulate the HPI axis in response to this environmental stressor, as well as elucidate potential interactions between these factors, we exposed rainbow trout to one of three ammonia levels (0, 650, 1000 μM NH<sub>4</sub>Cl) for 24 or 96 h and assessed the gene expression and circulating levels of key determinants of HPI axis activity. In parallel with circulating ammonia concentrations, plasma cortisol levels increased dose-dependently after 24 h of HEA exposure and partially recovered after 96 h. HEA exposure also elicited dose-, time-, and brain region-specific changes in components of the central serotonergic (5-HTergic; <em>tph2, htr1aa, htr1b, htr2c</em>), corticotropin-releasing factor (<em>crfb</em>), arginine vasotocin (<em>avt, avtr1a, avtr2</em>), and isotocin (<em>it, itr</em>) signaling systems. Moreover, while intraperitoneal injections of 5-HT<sub>1B</sub> and 5-HT<sub>2C</sub> receptor antagonists reduced basal cortisol levels, treatment with 5-HT<sub>1A</sub> and 5-HT<sub>2C</sub> receptor antagonists blocked the increase in plasma cortisol elicited by HEA. Finally, treatment with specific 5-HT receptor antagonists blunted the HEA-induced increases in brain preoptic area <em>crfb</em>, <em>avt</em>, and <em>it</em> expression. These findings implicate 5-HT and multiple peptidergic systems in the hypophysiotropic regulation of the HPI axis in response to HEA exposure and provide novel insight into the multifactorial neural circuitry mediating the neuroendocrine stress response in fishes.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"371 ","pages":"Article 114773"},"PeriodicalIF":2.1,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144514398","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 : 2025-06-26DOI: 10.1016/j.ygcen.2025.114774
Lisa L. Surber-Cunningham , Lucas S. Jimenez , Lauren W. Mobo , Sarah E. Westrick , Eva K. Fischer
In vertebrates, the glucocorticoid “stress” response (corticosterone or cortisol) through the hypothalamic–pituitary–adrenal (HPA) axis influences many essential functions, including behavior, metabolism, immunity, and ontogenetic transitions. During development, stress responses can be adaptive if they facilitate antipredator behavior and modulate developmental speed to adjust to environmental conditions; however, these same responses can be maladaptive when energetic costs become too high and developmental speed trades-off with size and health at maturity. Thus, the timing of HPA-axis development may be aligned with specific developmental challenges and opportunities presented by a species’ life history strategy. In anurans (frogs and toads), corticosterone plays critical roles in development and behavior, and concentrations can fluctuate in response to environmental stressors. Given the role of corticosterone in ontogenetic changes and behaviors, we studied the development of the glucocorticoid stress response in tadpoles of the dyeing poison frog (Dendrobates tinctorius), a species with a unique life history that includes transport to water after hatching on land and aggressive and cannibalistic behavior. We measured the excretion rate and whole-body concentration of corticosterone and the corticosterone response to adrenocorticotropic hormone (ACTH) in free-swimming tadpoles after transport and throughout metamorphosis. We found no significant differences across development in excretion rates or whole-body concentration of corticosterone, nor corticosterone response to ACTH, indicating that that the glucocorticoid response develops early in ontogeny. This pattern differs from those in other species, suggesting the unique ecological pressures faced by D. tinctorius have shaped the development of the glucocorticoid stress response in this species. More broadly, this study illustrates how life history strategies and tradeoffs impact the timing of the development of stress responsivity.
{"title":"Early development of the glucocorticoid stress response in dyeing poison frog tadpoles","authors":"Lisa L. Surber-Cunningham , Lucas S. Jimenez , Lauren W. Mobo , Sarah E. Westrick , Eva K. Fischer","doi":"10.1016/j.ygcen.2025.114774","DOIUrl":"10.1016/j.ygcen.2025.114774","url":null,"abstract":"<div><div>In vertebrates, the glucocorticoid “stress” response (corticosterone or cortisol) through the hypothalamic–pituitary–adrenal (HPA) axis influences many essential functions, including behavior, metabolism, immunity, and ontogenetic transitions. During development, stress responses can be adaptive if they facilitate antipredator behavior and modulate developmental speed to adjust to environmental conditions; however, these same responses can be maladaptive when energetic costs become too high and developmental speed trades-off with size and health at maturity. Thus, the timing of HPA-axis development may be aligned with specific developmental challenges and opportunities presented by a species’ life history strategy. In anurans (frogs and toads), corticosterone plays critical roles in development and behavior, and concentrations can fluctuate in response to environmental stressors. Given the role of corticosterone in ontogenetic changes and behaviors, we studied the development of the glucocorticoid stress response in tadpoles of the dyeing poison frog (<em>Dendrobates tinctorius</em>), a species with a unique life history that includes transport to water after hatching on land and aggressive and cannibalistic behavior. We measured the excretion rate and whole-body concentration of corticosterone and the corticosterone response to adrenocorticotropic hormone (ACTH) in free-swimming tadpoles after transport and throughout metamorphosis. We found no significant differences across development in excretion rates or whole-body concentration of corticosterone, nor corticosterone response to ACTH, indicating that that the glucocorticoid response develops early in ontogeny. This pattern differs from those in other species, suggesting the unique ecological pressures faced by <em>D. tinctorius</em> have shaped the development of the glucocorticoid stress response in this species. More broadly, this study illustrates how life history strategies and tradeoffs impact the timing of the development of stress responsivity.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"371 ","pages":"Article 114774"},"PeriodicalIF":2.1,"publicationDate":"2025-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144517918","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}
The role of neuropeptide Y (NPY) in regulating ovarian functions has primarily been studied in mammals, while it remains meagrely explored in non-mammalian vertebrates. Our study is the first to report ovarian expression of npy and its receptor, npyr, in a reptile, Hemidactylus flaviviridis. Quantitative real-time PCR analysis demonstrated high expression of npy/npyr during early and late recrudescence, while significantly low levels were noted during regression. The study also examined role of NPY in modulating lizard ovarian functions, wherein in vitro treatment of recrudescent ovaries with NPY increased the mRNA expression of anti-apoptotic gene B-cell lymphoma 2 (bcl 2), and suppressed pro-apoptotic gene cysteine-aspartic acid protease-3 (caspase 3). NPY also stimulated cell proliferation/differentiation markers; stem cell factor (scf), receptor tyrosine kinase (c-kit), proliferating cell nuclear antigen (pcna), growth differentiation factor-9 (gdf-9), bone morphogenetic protein-15 (bmp-15), as well as gonadotropin and sex steroid receptors, follicle stimulating hormone receptor (fshr), estrogen receptor α, β (er-α, er-β), and progesterone receptor (pr). Also, NPY influenced ovarian steroidogenesis by upregulating steroidogenic acute regulatory protein (star) and cytochrome P450a family 19 (cyp19) mRNA expression. However, steroid estimation by ELISA indicates NPY-mediated differential modulation of steroidogenesis as progesterone production was elevated, while estradiol production was inhibited. Further, ovarian npy/npyr was differentially regulated by gonadotropin, sex steroids, neuropeptides, and adipokines. Expression of ligand and receptor was stimulated by 5α-dihydrotestosterone (DHT), 17β-estradiol (E2), kisspeptin, leptin, and nesfatin-1 but inhibited by follicle stimulating hormone (FSH) and substance P. Taken together, present study provides a comprehensive picture of ovarian npy/npyr in wall lizard.
{"title":"Multifaceted role and regulation of neuropeptide Y in the ovary of wall lizard, Hemidactylus flaviviridis","authors":"Vishesh Chauhan , Umesh Rai , Mamta Tripathy , Sunil Kumar","doi":"10.1016/j.ygcen.2025.114772","DOIUrl":"10.1016/j.ygcen.2025.114772","url":null,"abstract":"<div><div>The role of neuropeptide Y (NPY) in regulating ovarian functions has primarily been studied in mammals, while it remains meagrely explored in non-mammalian vertebrates. Our study is the first to report ovarian expression of <em>npy</em> and its receptor, <em>npyr,</em> in a reptile, <em>Hemidactylus flaviviridis</em>. Quantitative real-time PCR analysis demonstrated high expression of <em>npy/npyr</em> during early and late recrudescence, while significantly low levels were noted during regression. The study also examined role of NPY in modulating lizard ovarian functions, wherein <em>in vitro</em> treatment of recrudescent ovaries with NPY increased the mRNA expression of anti-apoptotic gene B-cell lymphoma 2 (<em>bcl 2</em>), and suppressed pro-apoptotic gene cysteine-aspartic acid protease-3 (<em>caspase 3</em>). NPY also stimulated cell proliferation/differentiation markers; stem cell factor (<em>scf</em>)<em>,</em> receptor tyrosine kinase (<em>c-kit</em>), proliferating cell nuclear antigen (<em>pcna</em>), growth differentiation factor-9 (<em>gdf-9</em>)<em>,</em> bone morphogenetic protein-15 (<em>bmp-15</em>), as well as gonadotropin and sex steroid receptors, follicle stimulating hormone receptor (<em>fshr</em>)<em>,</em> estrogen receptor α, β (<em>er-α, er-β</em>), and progesterone receptor (<em>pr</em>). Also, NPY influenced ovarian steroidogenesis by upregulating steroidogenic acute regulatory protein (<em>star</em>) and cytochrome P450a family 19 (<em>cyp19</em>) mRNA expression. However, steroid estimation by ELISA indicates NPY-mediated differential modulation of steroidogenesis as progesterone production was elevated, while estradiol production was inhibited. Further, ovarian <em>npy/npyr</em> was differentially regulated by gonadotropin, sex steroids, neuropeptides, and adipokines. Expression of ligand and receptor was stimulated by 5α-dihydrotestosterone (DHT), 17β-estradiol (E<sub>2</sub>), kisspeptin, leptin, and nesfatin-1 but inhibited by follicle stimulating hormone (FSH) and substance P. Taken together, present study provides a comprehensive picture of ovarian <em>npy/npyr</em> in wall lizard.</div></div>","PeriodicalId":12582,"journal":{"name":"General and comparative endocrinology","volume":"371 ","pages":"Article 114772"},"PeriodicalIF":2.1,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144340004","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}